question_id
stringlengths 1
4
| question
stringlengths 26
249
| pos_item_ids
sequencelengths 1
5
| pos_item_contents
sequencelengths 1
5
|
|---|---|---|---|
364 | EGR2 is important to myelination of the peripheral nervous system. | [
"1550937"
] | [
"The Transcription Factors Egr2 and Egr3 Are Essential for the Control of Inflammation and Antigen-Induced Proliferation of B and T Cells. Lymphocytes provide optimal responses against pathogens with minimal inflammatory pathology. However, the intrinsic mechanisms regulating these responses are unknown. Here, we report that deletion of both transcription factors Egr2 and Egr3 in lymphocytes resulted in a lethal autoimmune syndrome with excessive serum proinflammatory cytokines but also impaired antigen receptor-induced proliferation of B and T cells. Egr2- and Egr3-defective B and T cells had hyperactive signal transducer and activator of transcription-1 (STAT1) and STAT3 while antigen receptor-induced activation of transcription factor AP-1 was severely impaired. We discovered that Egr2 and/or Egr3 directly induced expression of suppressor of cytokine signaling-1 (SOCS1) and SOCS3, inhibitors of STAT1 and STAT3, and also blocked the function of Batf, an AP-1 inhibitor, in B and T cells. Thus, Egr2 and Egr3 regulate B and T cell function in adaptive immune responses and homeostasis by promoting antigen receptor signaling and controlling inflammation."
] |
365 | ER-localized phosphatase Sac1 processes PI4P through coordination with OSBP and the endosome-localized protein sorting nexin 2. | [
"600437"
] | [
"Endosome-ER Contacts Control Actin Nucleation and Retromer Function through VAP-Dependent Regulation of PI4P. VAP (VAPA and VAPB) is an evolutionarily conserved endoplasmic reticulum (ER)-anchored protein that helps generate tethers between the ER and other membranes through which lipids are exchanged across adjacent bilayers. Here, we report that by regulating PI4P levels on endosomes, VAP affects WASH-dependent actin nucleation on these organelles and the function of the retromer, a protein coat responsible for endosome-to-Golgi traffic. VAP is recruited to retromer budding sites on endosomes via an interaction with the retromer SNX2 subunit. Cells lacking VAP accumulate high levels of PI4P, actin comets, and trans-Golgi proteins on endosomes. Such defects are mimicked by downregulation of OSBP, a VAP interactor and PI4P transporter that participates in VAP-dependent ER-endosomes tethers. These results reveal a role of PI4P in retromer-/WASH-dependent budding from endosomes. Collectively, our data show how the ER can control budding dynamics and association with the cytoskeleton of another membrane by direct contacts leading to bilayer lipid modifications."
] |
366 | ERAP1 SNPs are epistatic to HLA alleles for ankylosing spondylitis. | [
"13956305"
] | [
"Major histocompatibility complex associations of ankylosing spondylitis are complex and involve further epistasis with ERAP1. Ankylosing spondylitis (AS) is a common, highly heritable, inflammatory arthritis for which HLA-B*27 is the major genetic risk factor, although its role in the aetiology of AS remains elusive. To better understand the genetic basis of the MHC susceptibility loci, we genotyped 7,264 MHC SNPs in 22,647 AS cases and controls of European descent. We impute SNPs, classical HLA alleles and amino-acid residues within HLA proteins, and tested these for association to AS status. Here we show that in addition to effects due to HLA-B*27 alleles, several other HLA-B alleles also affect susceptibility. After controlling for the associated haplotypes in HLA-B, we observe independent associations with variants in the HLA-A, HLA-DPB1 and HLA-DRB1 loci. We also demonstrate that the ERAP1 SNP rs30187 association is not restricted only to carriers of HLA-B*27 but also found in HLA-B*40:01 carriers independently of HLA-B*27 genotype."
] |
367 | Early patent ductus ateriosus (PDA) screening decreases in-hospital mortality. | [
"27099731"
] | [
"Association Between Early Screening for Patent Ductus Arteriosus and In-Hospital Mortality Among Extremely Preterm Infants.. IMPORTANCE There is currently no consensus for the screening and treatment of patent ductus arteriosus (PDA) in extremely preterm infants. Less pharmacological closure and more supportive management have been observed without evidence to support these changes. OBJECTIVE To evaluate the association between early screening echocardiography for PDA and in-hospital mortality. DESIGN, SETTING, AND PARTICIPANTS Comparison of screened and not screened preterm infants enrolled in the EPIPAGE 2 national prospective population-based cohort study that included all preterm infants born at less than 29 weeks of gestation and hospitalized in 68 neonatal intensive care units in France from April through December 2011. Two main analyses were performed to adjust for potential selection bias, one using propensity score matching and one using neonatal unit preference for early screening echocardiography as an instrumental variable. EXPOSURES Early screening echocardiography before day 3 of life. MAIN OUTCOMES AND MEASURES The primary outcome was death between day 3 and discharge. The secondary outcomes were major neonatal morbidities (pulmonary hemorrhage, severe bronchopulmonary dysplasia, severe cerebral lesions, and necrotizing enterocolitis). RESULTS Among the 1513 preterm infants with data available to determine exposure, 847 were screened for PDA and 666 were not; 605 infants from each group could be paired. Exposed infants were treated for PDA more frequently during their hospitalization than nonexposed infants (55.1% vs 43.1%; odds ratio [OR], 1.62 [95% CI, 1.31 to 2.00]; absolute risk reduction [ARR] in events per 100 infants, -12.0 [95% CI, -17.3 to -6.7). Exposed infants had a lower hospital death rate (14.2% vs 18.5% ; OR, 0.73 [95% CI, 0.54 to 0.98]; ARR, 4.3 [95% CI, 0.3 to 8.3]) and a lower rate of pulmonary hemorrhage (5.6% vs 8.9%; OR, 0.60 [95% CI, 0.38 to 0.95]; ARR, 3.3 [95% CI, 0.4 to 6.3]). No differences in rates of necrotizing enterocolitis, severe bronchopulmonary dysplasia, or severe cerebral lesions were observed. In the overall cohort, instrumental variable analysis yielded an adjusted OR for in-hospital mortality of 0.62 [95% CI, 0.37 to 1.04]. CONCLUSIONS AND RELEVANCE In this national population-based cohort of extremely preterm infants, screening echocardiography before day 3 of life was associated with lower in-hospital mortality and likelihood of pulmonary hemorrhage but not with differences in necrotizing enterocolitis, severe bronchopulmonary dysplasia, or severe cerebral lesions. However, results of the instrumental variable analysis leave some ambiguity in the interpretation, and longer-term evaluation is needed to provide clarity."
] |
368 | Early patent ductus ateriosus (PDA) screening increases in-hospital mortality. | [
"27099731"
] | [
"Association Between Early Screening for Patent Ductus Arteriosus and In-Hospital Mortality Among Extremely Preterm Infants.. IMPORTANCE There is currently no consensus for the screening and treatment of patent ductus arteriosus (PDA) in extremely preterm infants. Less pharmacological closure and more supportive management have been observed without evidence to support these changes. OBJECTIVE To evaluate the association between early screening echocardiography for PDA and in-hospital mortality. DESIGN, SETTING, AND PARTICIPANTS Comparison of screened and not screened preterm infants enrolled in the EPIPAGE 2 national prospective population-based cohort study that included all preterm infants born at less than 29 weeks of gestation and hospitalized in 68 neonatal intensive care units in France from April through December 2011. Two main analyses were performed to adjust for potential selection bias, one using propensity score matching and one using neonatal unit preference for early screening echocardiography as an instrumental variable. EXPOSURES Early screening echocardiography before day 3 of life. MAIN OUTCOMES AND MEASURES The primary outcome was death between day 3 and discharge. The secondary outcomes were major neonatal morbidities (pulmonary hemorrhage, severe bronchopulmonary dysplasia, severe cerebral lesions, and necrotizing enterocolitis). RESULTS Among the 1513 preterm infants with data available to determine exposure, 847 were screened for PDA and 666 were not; 605 infants from each group could be paired. Exposed infants were treated for PDA more frequently during their hospitalization than nonexposed infants (55.1% vs 43.1%; odds ratio [OR], 1.62 [95% CI, 1.31 to 2.00]; absolute risk reduction [ARR] in events per 100 infants, -12.0 [95% CI, -17.3 to -6.7). Exposed infants had a lower hospital death rate (14.2% vs 18.5% ; OR, 0.73 [95% CI, 0.54 to 0.98]; ARR, 4.3 [95% CI, 0.3 to 8.3]) and a lower rate of pulmonary hemorrhage (5.6% vs 8.9%; OR, 0.60 [95% CI, 0.38 to 0.95]; ARR, 3.3 [95% CI, 0.4 to 6.3]). No differences in rates of necrotizing enterocolitis, severe bronchopulmonary dysplasia, or severe cerebral lesions were observed. In the overall cohort, instrumental variable analysis yielded an adjusted OR for in-hospital mortality of 0.62 [95% CI, 0.37 to 1.04]. CONCLUSIONS AND RELEVANCE In this national population-based cohort of extremely preterm infants, screening echocardiography before day 3 of life was associated with lower in-hospital mortality and likelihood of pulmonary hemorrhage but not with differences in necrotizing enterocolitis, severe bronchopulmonary dysplasia, or severe cerebral lesions. However, results of the instrumental variable analysis leave some ambiguity in the interpretation, and longer-term evaluation is needed to provide clarity."
] |
369 | Ectopic expression of Sall4, Nanog, Esrrb, and Lin28 generates induced pluripotent stem cells from mouse embryonic fibroblasts more efficiently than other factor combinations. | [
"6826100"
] | [
"The developmental potential of iPSCs is greatly influenced by reprogramming factor selection.. Induced pluripotent stem cells (iPSCs) are commonly generated by transduction of Oct4, Sox2, Klf4, and Myc (OSKM) into cells. Although iPSCs are pluripotent, they frequently exhibit high variation in terms of quality, as measured in mice by chimera contribution and tetraploid complementation. Reliably high-quality iPSCs will be needed for future therapeutic applications. Here, we show that one major determinant of iPSC quality is the combination of reprogramming factors used. Based on tetraploid complementation, we found that ectopic expression of Sall4, Nanog, Esrrb, and Lin28 (SNEL) in mouse embryonic fibroblasts (MEFs) generated high-quality iPSCs more efficiently than other combinations of factors including OSKM. Although differentially methylated regions, transcript number of master regulators, establishment of specific superenhancers, and global aneuploidy were comparable between high- and low-quality lines, aberrant gene expression, trisomy of chromosome 8, and abnormal H2A.X deposition were distinguishing features that could potentially also be applicable to human."
] |
37 | A deficiency of vitamin B6 decreases blood levels of homocysteine. | [
"5152028",
"11705328"
] | [
"Folic acid improves endothelial function in coronary artery disease via mechanisms largely independent of homocysteine lowering.. BACKGROUND Homocysteine is a risk factor for coronary artery disease (CAD), although a causal relation remains to be proven. The importance of determining direct causality rests in the fact that plasma homocysteine can be safely and inexpensively reduced by 25% with folic acid. This reduction is maximally achieved by doses of 0.4 mg/d. High-dose folic acid (5 mg/d) improves endothelial function in CAD, although the mechanism is controversial. It has been proposed that improvement occurs through reduction in total (tHcy) or free (non-protein bound) homocysteine (fHcy). We investigated the effects of folic acid on endothelial function before a change in homocysteine in patients with CAD. METHODS AND RESULTS A randomized, placebo-controlled study of folic acid (5 mg/d) for 6 weeks was undertaken in 33 patients. Endothelial function, assessed by flow-mediated dilatation (FMD), was measured before, at 2 and 4 hours after the first dose of folic acid, and after 6 weeks of treatment. Plasma folate increased markedly by 1 hour (200 compared with 25.8 nmol/L; P<0.001). FMD improved at 2 hours (83 compared with 47 microm; P<0.001) and was largely complete by 4 hours (101 compared with 51 microm; P<0.001). tHcy did not significantly differ acutely (4-hour tHcy, 9.56 compared with 9.79 micromol/L; P=NS). fHcy did not differ at 3 hours but was slightly reduced at 4 hours (1.55 compared with 1.78 micromol/L; P=0.02). FMD improvement did not correlate with reductions in either fHcy or tHcy at any time. CONCLUSIONS These data suggest that folic acid improves endothelial function in CAD acutely by a mechanism largely independent of homocysteine.",
"Randomized trial of folic acid supplementation and serum homocysteine levels.. BACKGROUND Lowering serum homocysteine levels with folic acid is expected to reduce mortality from ischemic heart disease. Homocysteine reduction is known to be maximal at a folic acid dosage of 1 mg/d, but the effect of lower doses (relevant to food fortification) is unclear. METHODS We randomized 151 patients with ischemic heart disease to 1 of 5 dosages of folic acid (0.2, 0.4, 0.6, 0.8, and 1.0 mg/d) or placebo. Fasting blood samples for serum homocysteine and serum folate analysis were taken initially, after 3 months of supplementation, and 3 months after folic acid use was discontinued. RESULTS Median serum homocysteine level decreased with increasing folic acid dosage, to a maximum at 0.8 mg of folic acid per day, when the homocysteine reduction (placebo adjusted) was 2.7 micromol/L (23%), similar to the known effect of folic acid dosages of 1 mg/d and above. The higher a person's initial serum homocysteine level, the greater was the response to folic acid, but there were statistically significant reductions regardless of the initial level. Serum folate level increased approximately linearly (5.5 nmol/L for every 0.1 mg of folic acid). Within-person fluctuations over time in serum homocysteine levels, measured in the placebo group, were large compared with the effect of folic acid, indicating that monitoring of the reduction in an individual is impractical. CONCLUSIONS A dosage of folic acid of 0.8 mg/d appears necessary to achieve the maximum reduction in serum homocysteine level across the range of homocysteine levels in the population. Current US food fortification levels will achieve only a small proportion of the achievable homocysteine reduction."
] |
370 | Egr2 regulates the homeostasis of B and T cells. | [
"1550937"
] | [
"The Transcription Factors Egr2 and Egr3 Are Essential for the Control of Inflammation and Antigen-Induced Proliferation of B and T Cells. Lymphocytes provide optimal responses against pathogens with minimal inflammatory pathology. However, the intrinsic mechanisms regulating these responses are unknown. Here, we report that deletion of both transcription factors Egr2 and Egr3 in lymphocytes resulted in a lethal autoimmune syndrome with excessive serum proinflammatory cytokines but also impaired antigen receptor-induced proliferation of B and T cells. Egr2- and Egr3-defective B and T cells had hyperactive signal transducer and activator of transcription-1 (STAT1) and STAT3 while antigen receptor-induced activation of transcription factor AP-1 was severely impaired. We discovered that Egr2 and/or Egr3 directly induced expression of suppressor of cytokine signaling-1 (SOCS1) and SOCS3, inhibitors of STAT1 and STAT3, and also blocked the function of Batf, an AP-1 inhibitor, in B and T cells. Thus, Egr2 and Egr3 regulate B and T cell function in adaptive immune responses and homeostasis by promoting antigen receptor signaling and controlling inflammation."
] |
371 | Egr3 regulates the homeostasis of B and T cells. | [
"1550937"
] | [
"The Transcription Factors Egr2 and Egr3 Are Essential for the Control of Inflammation and Antigen-Induced Proliferation of B and T Cells. Lymphocytes provide optimal responses against pathogens with minimal inflammatory pathology. However, the intrinsic mechanisms regulating these responses are unknown. Here, we report that deletion of both transcription factors Egr2 and Egr3 in lymphocytes resulted in a lethal autoimmune syndrome with excessive serum proinflammatory cytokines but also impaired antigen receptor-induced proliferation of B and T cells. Egr2- and Egr3-defective B and T cells had hyperactive signal transducer and activator of transcription-1 (STAT1) and STAT3 while antigen receptor-induced activation of transcription factor AP-1 was severely impaired. We discovered that Egr2 and/or Egr3 directly induced expression of suppressor of cytokine signaling-1 (SOCS1) and SOCS3, inhibitors of STAT1 and STAT3, and also blocked the function of Batf, an AP-1 inhibitor, in B and T cells. Thus, Egr2 and Egr3 regulate B and T cell function in adaptive immune responses and homeostasis by promoting antigen receptor signaling and controlling inflammation."
] |
372 | Eilat virus (EILV) produced in mosquitos elicits rapid and long-lasting neutralizing antibodies in nonhuman primates. | [
"24922825"
] | [
"A chikungunya fever vaccine utilizing an insect-specific virus platform. Traditionally, vaccine development involves tradeoffs between immunogenicity and safety. Live-attenuated vaccines typically offer rapid and durable immunity but have reduced safety when compared to inactivated vaccines. In contrast, the inability of inactivated vaccines to replicate enhances safety at the expense of immunogenicity, often necessitating multiple doses and boosters. To overcome these tradeoffs, we developed the insect-specific alphavirus, Eilat virus (EILV), as a vaccine platform. To address the chikungunya fever (CHIKF) pandemic, we used an EILV cDNA clone to design a chimeric virus containing the chikungunya virus (CHIKV) structural proteins. The recombinant EILV/CHIKV was structurally identical at 10 Å to wild-type CHIKV, as determined by single-particle cryo-electron microscopy, and it mimicked the early stages of CHIKV replication in vertebrate cells from attachment and entry to viral RNA delivery. Yet the recombinant virus remained completely defective for productive replication, providing a high degree of safety. A single dose of EILV/CHIKV produced in mosquito cells elicited rapid (within 4 d) and long-lasting (>290 d) neutralizing antibodies that provided complete protection in two different mouse models. In nonhuman primates, EILV/CHIKV elicited rapid and robust immunity that protected against viremia and telemetrically monitored fever. Our EILV platform represents the first structurally native application of an insect-specific virus in preclinical vaccine development and highlights the potential application of such viruses in vaccinology."
] |
375 | Elevated cell-free mitochondrial DNA levels are associated with mortality. | [
"1522647"
] | [
"Circulating Mitochondrial DNA in Patients in the ICU as a Marker of Mortality: Derivation and Validation. BACKGROUND Mitochondrial DNA (mtDNA) is a critical activator of inflammation and the innate immune system. However, mtDNA level has not been tested for its role as a biomarker in the intensive care unit (ICU). We hypothesized that circulating cell-free mtDNA levels would be associated with mortality and improve risk prediction in ICU patients. METHODS AND FINDINGS Analyses of mtDNA levels were performed on blood samples obtained from two prospective observational cohort studies of ICU patients (the Brigham and Women's Hospital Registry of Critical Illness [BWH RoCI, n = 200] and Molecular Epidemiology of Acute Respiratory Distress Syndrome [ME ARDS, n = 243]). mtDNA levels in plasma were assessed by measuring the copy number of the NADH dehydrogenase 1 gene using quantitative real-time PCR. Medical ICU patients with an elevated mtDNA level (≥3,200 copies/µl plasma) had increased odds of dying within 28 d of ICU admission in both the BWH RoCI (odds ratio [OR] 7.5, 95% CI 3.6-15.8, p = 1×10(-7)) and ME ARDS (OR 8.4, 95% CI 2.9-24.2, p = 9×10(-5)) cohorts, while no evidence for association was noted in non-medical ICU patients. The addition of an elevated mtDNA level improved the net reclassification index (NRI) of 28-d mortality among medical ICU patients when added to clinical models in both the BWH RoCI (NRI 79%, standard error 14%, p<1×10(-4)) and ME ARDS (NRI 55%, standard error 20%, p = 0.007) cohorts. In the BWH RoCI cohort, those with an elevated mtDNA level had an increased risk of death, even in analyses limited to patients with sepsis or acute respiratory distress syndrome. Study limitations include the lack of data elucidating the concise pathological roles of mtDNA in the patients, and the limited numbers of measurements for some of biomarkers. CONCLUSIONS Increased mtDNA levels are associated with ICU mortality, and inclusion of mtDNA level improves risk prediction in medical ICU patients. Our data suggest that mtDNA could serve as a viable plasma biomarker in medical ICU patients."
] |
376 | Eliminating the last sporadic cases of malaria requires considerable funding. | [
"22401061"
] | [
"Costs and financial feasibility of malaria elimination. The marginal costs and benefits of converting malaria programmes from a control to an elimination goal are central to strategic decisions, but empirical evidence is scarce. We present a conceptual framework to assess the economics of elimination and analyse a central component of that framework-potential short-term to medium-term financial savings. After a review that showed a dearth of existing evidence, the net present value of elimination in five sites was calculated and compared with effective control. The probability that elimination would be cost-saving over 50 years ranged from 0% to 42%, with only one site achieving cost-savings in the base case. These findings show that financial savings should not be a primary rationale for elimination, but that elimination might still be a worthy investment if total benefits are sufficient to outweigh marginal costs. Robust research into these elimination benefits is urgently needed."
] |
377 | Emodin forms hydrogen bonds with residues involved in PGAM1 substrate binding. | [
"18810195"
] | [
"Tyr26 phosphorylation of PGAM1 provides a metabolic advantage to tumours by stabilizing the active conformation. How oncogenic signalling coordinates glycolysis and anabolic biosynthesis in cancer cells remains unclear. We recently reported that the glycolytic enzyme phosphoglycerate mutase 1 (PGAM1) regulates anabolic biosynthesis by controlling intracellular levels of its substrate 3-phosphoglycerate and product 2-phosphoglycerate. Here we report a novel mechanism in which Y26 phosphorylation enhances PGAM1 activation through release of inhibitory E19 that blocks the active site, stabilising cofactor 2,3-bisphosphoglycerate binding and H11 phosphorylation. We also report the crystal structure of H11-phosphorylated PGAM1 and find that phospho-H11 activates PGAM1 at least in part by promoting substrate 3-phosphoglycerate binding. Moreover, Y26 phosphorylation of PGAM1 is common in human cancer cells and contributes to regulation of 3-phosphoglycerate and 2-phosphoglycerate levels, promoting cancer cell proliferation and tumour growth. As PGAM1 is a negative transcriptional target of TP53, and is therefore commonly upregulated in human cancers, these findings suggest that Y26 phosphorylation represents an additional acute mechanism underlying phosphoglycerate mutase 1 upregulation."
] |
378 | Energy balance requires hypothalamic glutamate neurotransmission. | [
"45154987",
"10534299",
"11886686",
"25007443",
"17150648"
] | [
"Glutamate mediates the function of melanocortin receptor 4 on Sim1 neurons in body weight regulation.. The melanocortin receptor 4 (MC4R) is a well-established mediator of body weight homeostasis. However, the neurotransmitter(s) that mediate MC4R function remain largely unknown; as a result, little is known about the second-order neurons of the MC4R neural pathway. Single-minded 1 (Sim1)-expressing brain regions, which include the paraventricular nucleus of hypothalamus (PVH), represent key brain sites that mediate melanocortin action. We conditionally restored MC4R expression in Sim1 neurons in the background of Mc4r-null mice. The restoration dramatically reduced obesity in Mc4r-null mice. The anti-obesity effect was completely reversed by selective disruption of glutamate release from those same Sim1 neurons. The reversal was caused by lower energy expenditure and hyperphagia. Corroboratively, selective disruption of glutamate release from adult PVH neurons led to rapid obesity development via reduced energy expenditure and hyperphagia. Thus, this study establishes glutamate as the primary neurotransmitter that mediates MC4Rs on Sim1 neurons in body weight regulation.",
"Fasting Activation of AgRP Neurons Requires NMDA Receptors and Involves Spinogenesis and Increased Excitatory Tone. AgRP neuron activity drives feeding and weight gain whereas that of nearby POMC neurons does the opposite. However, the role of excitatory glutamatergic input in controlling these neurons is unknown. To address this question, we generated mice lacking NMDA receptors (NMDARs) on either AgRP or POMC neurons. Deletion of NMDARs from AgRP neurons markedly reduced weight, body fat and food intake whereas deletion from POMC neurons had no effect. Activation of AgRP neurons by fasting, as assessed by c-Fos, Agrp and Npy mRNA expression, AMPA receptor-mediated EPSCs, depolarization and firing rates, required NMDARs. Furthermore, AgRP but not POMC neurons have dendritic spines and increased glutamatergic input onto AgRP neurons caused by fasting was paralleled by an increase in spines, suggesting fasting induced synaptogenesis and spinogenesis. Thus glutamatergic synaptic transmission and its modulation by NMDARs play key roles in controlling AgRP neurons and determining the cellular and behavioral response to fasting.",
"Synaptic glutamate release by ventromedial hypothalamic neurons is part of the neurocircuitry that prevents hypoglycemia.. The importance of neuropeptides in the hypothalamus has been experimentally established. Due to difficulties in assessing function in vivo, the roles of the fast-acting neurotransmitters glutamate and GABA are largely unknown. Synaptic vesicular transporters (VGLUTs for glutamate and VGAT for GABA) are required for vesicular uptake and, consequently, synaptic release of neurotransmitters. Ventromedial hypothalamic (VMH) neurons are predominantly glutamatergic and express VGLUT2. To evaluate the role of glutamate release from VMH neurons, we generated mice lacking VGLUT2 selectively in SF1 neurons (a major subset of VMH neurons). These mice have hypoglycemia during fasting secondary to impaired fasting-induced increases in the glucose-raising pancreatic hormone glucagon and impaired induction in liver of mRNAs encoding PGC-1alpha and the gluconeogenic enzymes PEPCK and G6Pase. Similarly, these mice have defective counterregulatory responses to insulin-induced hypoglycemia and 2-deoxyglucose (an antimetabolite). Thus, glutamate release from VMH neurons is an important component of the neurocircuitry that functions to prevent hypoglycemia.",
"Topographic mapping of VMH → arcuate nucleus microcircuits and their reorganization by fasting. In the hypothalamic arcuate nucleus (ARC), pro-opiomelanocortin (POMC) neurons inhibit feeding and neuropeptide-Y (NPY) neurons stimulate feeding. We tested whether neurons in the ventromedial hypothalamic nucleus (VMH), a known satiety center, activate anorexigenic neuronal pathways in the ARC by projecting either excitatory synaptic inputs to POMC neurons and/or inhibitory inputs to NPY neurons. Using laser scanning photostimulation in brain slices from transgenic mice, we found that POMC and NPY neurons, which are interspersed in the ARC, are nevertheless regulated by anatomically distinct synaptic inputs. POMC neurons received strong excitatory input from the medial VMH (mVMH), whereas NPY neurons did not and, instead, received weak inhibitory input only from within the ARC. The strength of the excitatory input from the mVMH to POMC neurons was diminished by fasting. These data identify a new molecularly defined circuit that is dynamically regulated by nutritional state in a manner consistent with the known role of the VMH as a satiety center.",
"Leptin regulates glutamate and glucose transporters in hypothalamic astrocytes.. Glial cells perform critical functions that alter the metabolism and activity of neurons, and there is increasing interest in their role in appetite and energy balance. Leptin, a key regulator of appetite and metabolism, has previously been reported to influence glial structural proteins and morphology. Here, we demonstrate that metabolic status and leptin also modify astrocyte-specific glutamate and glucose transporters, indicating that metabolic signals influence synaptic efficacy and glucose uptake and, ultimately, neuronal function. We found that basal and glucose-stimulated electrical activity of hypothalamic proopiomelanocortin (POMC) neurons in mice were altered in the offspring of mothers fed a high-fat diet. In adulthood, increased body weight and fasting also altered the expression of glucose and glutamate transporters. These results demonstrate that whole-organism metabolism alters hypothalamic glial cell activity and suggest that these cells play an important role in the pathology of obesity."
] |
379 | Enhanced early production of inflammatory chemokines damages viral control in the lung. | [
"19005293"
] | [
"Memory CD4+ T cells induce innate responses independently of pathogen. Inflammation induced by recognition of pathogen-associated molecular patterns markedly affects subsequent adaptive responses. We asked whether the adaptive immune system can also affect the character and magnitude of innate inflammatory responses. We found that the response of memory, but not naive, CD4+ T cells enhances production of multiple innate inflammatory cytokines and chemokines (IICs) in the lung and that, during influenza infection, this leads to early control of virus. Memory CD4+ T cell–induced IICs and viral control require cognate antigen recognition and are optimal when memory cells are either T helper type 1 (TH1) or TH17 polarized but are independent of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) production and do not require activation of conserved pathogen recognition pathways. This represents a previously undescribed mechanism by which memory CD4+ T cells induce an early innate response that enhances immune protection against pathogens."
] |
381 | Environmental factors can influence the development of breast cancer. | [
"18340282"
] | [
"Gene–environment interactions in 7610 women with breast cancer: prospective evidence from the Million Women Study. BACKGROUND Information is scarce about the combined effects on breast cancer incidence of low-penetrance genetic susceptibility polymorphisms and environmental factors (reproductive, behavioural, and anthropometric risk factors for breast cancer). To test for evidence of gene-environment interactions, we compared genotypic relative risks for breast cancer across the other risk factors in a large UK prospective study. METHODS We tested gene-environment interactions in 7610 women who developed breast cancer and 10 196 controls without the disease, studying the effects of 12 polymorphisms (FGFR2-rs2981582, TNRC9-rs3803662, 2q35-rs13387042, MAP3K1-rs889312, 8q24-rs13281615, 2p-rs4666451, 5p12-rs981782, CASP8-rs1045485, LSP1-rs3817198, 5q-rs30099, TGFB1-rs1982073, and ATM-rs1800054) in relation to prospectively collected information about ten established environmental risk factors (age at menarche, parity, age at first birth, breastfeeding, menopausal status, age at menopause, use of hormone replacement therapy, body-mass index, height, and alcohol consumption). FINDINGS After allowance for multiple testing none of the 120 comparisons yielded significant evidence of a gene-environment interaction. By contrast with previous suggestions, there was little evidence that the genotypic relative risks were affected by use of hormone replacement therapy, either overall or for oestrogen-receptor-positive disease. Only one of the 12 polymorphisms was correlated with any of the ten other risk factors: carriers of the high-risk C allele of MAP3K1-rs889312 were significantly shorter than non-carriers (mean height 162.4 cm [95% CI 162.1-162.7] vs 163.1 cm [162.9-163.2]; p=0.01 after allowance for multiple testing). INTERPRETATION Risks of breast cancer associated with low-penetrance susceptibility polymorphisms do not vary significantly with these ten established environmental risk factors. FUNDING Cancer Research UK and the UK Medical Research Council."
] |
382 | Environmentally-induced senescence is mimicked in disease modeling by adding specific molecules to the culture system. | [
"11659421"
] | [
"Human iPSC-based modeling of late-onset disease via progerin-induced aging.. Reprogramming somatic cells to induced pluripotent stem cells (iPSCs) resets their identity back to an embryonic age and, thus, presents a significant hurdle for modeling late-onset disorders. In this study, we describe a strategy for inducing aging-related features in human iPSC-derived lineages and apply it to the modeling of Parkinson's disease (PD). Our approach involves expression of progerin, a truncated form of lamin A associated with premature aging. We found that expression of progerin in iPSC-derived fibroblasts and neurons induces multiple aging-related markers and characteristics, including dopamine-specific phenotypes such as neuromelanin accumulation. Induced aging in PD iPSC-derived dopamine neurons revealed disease phenotypes that require both aging and genetic susceptibility, such as pronounced dendrite degeneration, progressive loss of tyrosine hydroxylase (TH) expression, and enlarged mitochondria or Lewy-body-precursor inclusions. Thus, our study suggests that progerin-induced aging can be used to reveal late-onset age-related disease features in hiPSC-based disease models."
] |
383 | Epidemiological disease burden from noncommunicable diseases is more prevalent in high economic settings. | [
"13770184"
] | [
"Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. BACKGROUND The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context. METHODS We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors-the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI). FINDINGS Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6-58·8) of global deaths and 41·2% (39·8-42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa. INTERPRETATION Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden. FUNDING Bill & Melinda Gates Foundation."
] |
389 | Ethanol stress increases the expression of IBP in bacteria. | [
"1148122"
] | [
"Regulatory and metabolic rewiring during laboratory evolution of ethanol tolerance in E. coli. Understanding the genetic basis of adaptation is a central problem in biology. However, revealing the underlying molecular mechanisms has been challenging as changes in fitness may result from perturbations to many pathways, any of which may contribute relatively little. We have developed a combined experimental/computational framework to address this problem and used it to understand the genetic basis of ethanol tolerance in Escherichia coli. We used fitness profiling to measure the consequences of single-locus perturbations in the context of ethanol exposure. A module-level computational analysis was then used to reveal the organization of the contributing loci into cellular processes and regulatory pathways (e.g. osmoregulation and cell-wall biogenesis) whose modifications significantly affect ethanol tolerance. Strikingly, we discovered that a dominant component of adaptation involves metabolic rewiring that boosts intracellular ethanol degradation and assimilation. Through phenotypic and metabolomic analysis of laboratory-evolved ethanol-tolerant strains, we investigated naturally accessible pathways of ethanol tolerance. Remarkably, these laboratory-evolved strains, by and large, follow the same adaptive paths as inferred from our coarse-grained search of the fitness landscape."
] |
39 | A diminished ovarian reserve does not solely indicate infertility in an a priori non-infertile population. | [
"13497630"
] | [
"Association Between Biomarkers of Ovarian Reserve and Infertility Among Older Women of Reproductive Age. Importance Despite lack of evidence of their utility, biomarkers of ovarian reserve are being promoted as potential markers of reproductive potential. Objective To determine the associations between biomarkers of ovarian reserve and reproductive potential among women of late reproductive age. Design, Setting, and Participants Prospective time-to-pregnancy cohort study (2008 to date of last follow-up in March 2016) of women (N = 981) aged 30 to 44 years without a history of infertility who had been trying to conceive for 3 months or less, recruited from the community in the Raleigh-Durham, North Carolina, area. Exposures Early-follicular-phase serum level of antimüllerian hormone (AMH), follicle-stimulating hormone (FSH), and inhibin B and urinary level of FSH. Main Outcomes and Measures The primary outcomes were the cumulative probability of conception by 6 and 12 cycles of attempt and relative fecundability (probability of conception in a given menstrual cycle). Conception was defined as a positive pregnancy test result. Results A total of 750 women (mean age, 33.3 [SD, 3.2] years; 77% white; 36% overweight or obese) provided a blood and urine sample and were included in the analysis. After adjusting for age, body mass index, race, current smoking status, and recent hormonal contraceptive use, women with low AMH values (<0.7 ng/mL [n = 84]) did not have a significantly different predicted probability of conceiving by 6 cycles of attempt (65%; 95% CI, 50%-75%) compared with women (n = 579) with normal values (62%; 95% CI, 57%-66%) or by 12 cycles of attempt (84% [95% CI, 70%-91%] vs 75% [95% CI, 70%-79%], respectively). Women with high serum FSH values (>10 mIU/mL [n = 83]) did not have a significantly different predicted probability of conceiving after 6 cycles of attempt (63%; 95% CI, 50%-73%) compared with women (n = 654) with normal values (62%; 95% CI, 57%-66%) or after 12 cycles of attempt (82% [95% CI, 70%-89%] vs 75% [95% CI, 70%-78%], respectively). Women with high urinary FSH values (>11.5 mIU/mg creatinine [n = 69]) did not have a significantly different predicted probability of conceiving after 6 cycles of attempt (61%; 95% CI, 46%-74%) compared with women (n = 660) with normal values (62%; 95% CI, 58%-66%) or after 12 cycles of attempt (70% [95% CI, 54%-80%] vs 76% [95% CI, 72%-80%], respectively). Inhibin B levels (n = 737) were not associated with the probability of conceiving in a given cycle (hazard ratio per 1-pg/mL increase, 0.999; 95% CI, 0.997-1.001). Conclusions and Relevance Among women aged 30 to 44 years without a history of infertility who had been trying to conceive for 3 months or less, biomarkers indicating diminished ovarian reserve compared with normal ovarian reserve were not associated with reduced fertility. These findings do not support the use of urinary or blood follicle-stimulating hormone tests or antimüllerian hormone levels to assess natural fertility for women with these characteristics."
] |
390 | Ethanol stress increases the expression of PSP in bacteria. | [
"1148122"
] | [
"Regulatory and metabolic rewiring during laboratory evolution of ethanol tolerance in E. coli. Understanding the genetic basis of adaptation is a central problem in biology. However, revealing the underlying molecular mechanisms has been challenging as changes in fitness may result from perturbations to many pathways, any of which may contribute relatively little. We have developed a combined experimental/computational framework to address this problem and used it to understand the genetic basis of ethanol tolerance in Escherichia coli. We used fitness profiling to measure the consequences of single-locus perturbations in the context of ethanol exposure. A module-level computational analysis was then used to reveal the organization of the contributing loci into cellular processes and regulatory pathways (e.g. osmoregulation and cell-wall biogenesis) whose modifications significantly affect ethanol tolerance. Strikingly, we discovered that a dominant component of adaptation involves metabolic rewiring that boosts intracellular ethanol degradation and assimilation. Through phenotypic and metabolomic analysis of laboratory-evolved ethanol-tolerant strains, we investigated naturally accessible pathways of ethanol tolerance. Remarkably, these laboratory-evolved strains, by and large, follow the same adaptive paths as inferred from our coarse-grained search of the fitness landscape."
] |
391 | Ethanol stress increases the expression of SRL in bacteria. | [
"1148122"
] | [
"Regulatory and metabolic rewiring during laboratory evolution of ethanol tolerance in E. coli. Understanding the genetic basis of adaptation is a central problem in biology. However, revealing the underlying molecular mechanisms has been challenging as changes in fitness may result from perturbations to many pathways, any of which may contribute relatively little. We have developed a combined experimental/computational framework to address this problem and used it to understand the genetic basis of ethanol tolerance in Escherichia coli. We used fitness profiling to measure the consequences of single-locus perturbations in the context of ethanol exposure. A module-level computational analysis was then used to reveal the organization of the contributing loci into cellular processes and regulatory pathways (e.g. osmoregulation and cell-wall biogenesis) whose modifications significantly affect ethanol tolerance. Strikingly, we discovered that a dominant component of adaptation involves metabolic rewiring that boosts intracellular ethanol degradation and assimilation. Through phenotypic and metabolomic analysis of laboratory-evolved ethanol-tolerant strains, we investigated naturally accessible pathways of ethanol tolerance. Remarkably, these laboratory-evolved strains, by and large, follow the same adaptive paths as inferred from our coarse-grained search of the fitness landscape."
] |
392 | Ethanol stress lowers the expression of PSP in bacteria. | [
"1148122"
] | [
"Regulatory and metabolic rewiring during laboratory evolution of ethanol tolerance in E. coli. Understanding the genetic basis of adaptation is a central problem in biology. However, revealing the underlying molecular mechanisms has been challenging as changes in fitness may result from perturbations to many pathways, any of which may contribute relatively little. We have developed a combined experimental/computational framework to address this problem and used it to understand the genetic basis of ethanol tolerance in Escherichia coli. We used fitness profiling to measure the consequences of single-locus perturbations in the context of ethanol exposure. A module-level computational analysis was then used to reveal the organization of the contributing loci into cellular processes and regulatory pathways (e.g. osmoregulation and cell-wall biogenesis) whose modifications significantly affect ethanol tolerance. Strikingly, we discovered that a dominant component of adaptation involves metabolic rewiring that boosts intracellular ethanol degradation and assimilation. Through phenotypic and metabolomic analysis of laboratory-evolved ethanol-tolerant strains, we investigated naturally accessible pathways of ethanol tolerance. Remarkably, these laboratory-evolved strains, by and large, follow the same adaptive paths as inferred from our coarse-grained search of the fitness landscape."
] |
393 | Ethanol stress reduces the expression of SRL in bacteria. | [
"1148122"
] | [
"Regulatory and metabolic rewiring during laboratory evolution of ethanol tolerance in E. coli. Understanding the genetic basis of adaptation is a central problem in biology. However, revealing the underlying molecular mechanisms has been challenging as changes in fitness may result from perturbations to many pathways, any of which may contribute relatively little. We have developed a combined experimental/computational framework to address this problem and used it to understand the genetic basis of ethanol tolerance in Escherichia coli. We used fitness profiling to measure the consequences of single-locus perturbations in the context of ethanol exposure. A module-level computational analysis was then used to reveal the organization of the contributing loci into cellular processes and regulatory pathways (e.g. osmoregulation and cell-wall biogenesis) whose modifications significantly affect ethanol tolerance. Strikingly, we discovered that a dominant component of adaptation involves metabolic rewiring that boosts intracellular ethanol degradation and assimilation. Through phenotypic and metabolomic analysis of laboratory-evolved ethanol-tolerant strains, we investigated naturally accessible pathways of ethanol tolerance. Remarkably, these laboratory-evolved strains, by and large, follow the same adaptive paths as inferred from our coarse-grained search of the fitness landscape."
] |
394 | Excess gestational weight gain is associated with obesity-related pregnancy outcomes. | [
"11360768"
] | [
"Effects of interventions in pregnancy on maternal weight and obstetric outcomes: meta-analysis of randomised evidence. OBJECTIVE To evaluate the effects of dietary and lifestyle interventions in pregnancy on maternal and fetal weight and to quantify the effects of these interventions on obstetric outcomes. DESIGN Systematic review and meta-analysis. DATA SOURCES Major databases from inception to January 2012 without language restrictions. STUDY SELECTION Randomised controlled trials that evaluated any dietary or lifestyle interventions with potential to influence maternal weight during pregnancy and outcomes of pregnancy. DATA SYNTHESIS Results summarised as relative risks for dichotomous data and mean differences for continuous data. RESULTS We identified 44 relevant randomised controlled trials (7278 women) evaluating three categories of interventions: diet, physical activity, and a mixed approach. Overall, there was 1.42 kg reduction (95% confidence interval 0.95 to 1.89 kg) in gestational weight gain with any intervention compared with control. With all interventions combined, there were no significant differences in birth weight (mean difference -50 g, -100 to 0 g) and the incidence of large for gestational age (relative risk 0.85, 0.66 to 1.09) or small for gestational age (1.00, 0.78 to 1.28) babies between the groups, though by itself physical activity was associated with reduced birth weight (mean difference -60 g, -120 to -10 g). Interventions were associated with a reduced the risk of pre-eclampsia (0.74, 0.60 to 0.92) and shoulder dystocia (0.39, 0.22 to 0.70), with no significant effect on other critically important outcomes. Dietary intervention resulted in the largest reduction in maternal gestational weight gain (3.84 kg, 2.45 to 5.22 kg), with improved pregnancy outcomes compared with other interventions. The overall evidence rating was low to very low for important outcomes such as pre-eclampsia, gestational diabetes, gestational hypertension, and preterm delivery. CONCLUSIONS Dietary and lifestyle interventions in pregnancy can reduce maternal gestational weight gain and improve outcomes for both mother and baby. Among the interventions, those based on diet are the most effective and are associated with reductions in maternal gestational weight gain and improved obstetric outcomes."
] |
396 | Exercise increases cancer mortality rates among Chinese citizens. | [
"1456068"
] | [
"Combined Impact of Lifestyle-Related Factors on Total and Cause-Specific Mortality among Chinese Women: Prospective Cohort Study. BACKGROUND Although cigarette smoking, excessive alcohol drinking, obesity, and several other well-studied unhealthy lifestyle-related factors each have been linked to the risk of multiple chronic diseases and premature death, little is known about the combined impact on mortality outcomes, in particular among Chinese and other non-Western populations. The objective of this study was to quantify the overall impact of lifestyle-related factors beyond that of active cigarette smoking and alcohol consumption on all-cause and cause-specific mortality in Chinese women. METHODS AND FINDINGS We used data from the Shanghai Women's Health Study, an ongoing population-based prospective cohort study in China. Participants included 71,243 women aged 40 to 70 years enrolled during 1996-2000 who never smoked or drank alcohol regularly. A healthy lifestyle score was created on the basis of five lifestyle-related factors shown to be independently associated with mortality outcomes (normal weight, lower waist-hip ratio, daily exercise, never exposed to spouse's smoking, higher daily fruit and vegetable intake). The score ranged from zero (least healthy) to five (most healthy) points. During an average follow-up of 9 years, 2,860 deaths occurred, including 775 from cardiovascular disease (CVD) and 1,351 from cancer. Adjusted hazard ratios for mortality decreased progressively with an increasing number of healthy lifestyle factors. Compared to women with a score of zero, hazard ratios (95% confidence intervals) for women with four to five factors were 0.57 (0.44-0.74) for total mortality, 0.29 (0.16-0.54) for CVD mortality, and 0.76 (0.54-1.06) for cancer mortality. The inverse association between the healthy lifestyle score and mortality was seen consistently regardless of chronic disease status at baseline. The population attributable risks for not having 4-5 healthy lifestyle factors were 33% for total deaths, 59% for CVD deaths, and 19% for cancer deaths. CONCLUSIONS In this first study, to our knowledge, to quantify the combined impact of lifestyle-related factors on mortality outcomes in Chinese women, a healthier lifestyle pattern-including being of normal weight, lower central adiposity, participation in physical activity, nonexposure to spousal smoking, and higher fruit and vegetable intake-was associated with reductions in total and cause-specific mortality among lifetime nonsmoking and nondrinking women, supporting the importance of overall lifestyle modification in disease prevention. Please see later in the article for the Editors' Summary."
] |
397 | Exercise reduces cancer mortality rates among Chinese citizens. | [
"1456068"
] | [
"Combined Impact of Lifestyle-Related Factors on Total and Cause-Specific Mortality among Chinese Women: Prospective Cohort Study. BACKGROUND Although cigarette smoking, excessive alcohol drinking, obesity, and several other well-studied unhealthy lifestyle-related factors each have been linked to the risk of multiple chronic diseases and premature death, little is known about the combined impact on mortality outcomes, in particular among Chinese and other non-Western populations. The objective of this study was to quantify the overall impact of lifestyle-related factors beyond that of active cigarette smoking and alcohol consumption on all-cause and cause-specific mortality in Chinese women. METHODS AND FINDINGS We used data from the Shanghai Women's Health Study, an ongoing population-based prospective cohort study in China. Participants included 71,243 women aged 40 to 70 years enrolled during 1996-2000 who never smoked or drank alcohol regularly. A healthy lifestyle score was created on the basis of five lifestyle-related factors shown to be independently associated with mortality outcomes (normal weight, lower waist-hip ratio, daily exercise, never exposed to spouse's smoking, higher daily fruit and vegetable intake). The score ranged from zero (least healthy) to five (most healthy) points. During an average follow-up of 9 years, 2,860 deaths occurred, including 775 from cardiovascular disease (CVD) and 1,351 from cancer. Adjusted hazard ratios for mortality decreased progressively with an increasing number of healthy lifestyle factors. Compared to women with a score of zero, hazard ratios (95% confidence intervals) for women with four to five factors were 0.57 (0.44-0.74) for total mortality, 0.29 (0.16-0.54) for CVD mortality, and 0.76 (0.54-1.06) for cancer mortality. The inverse association between the healthy lifestyle score and mortality was seen consistently regardless of chronic disease status at baseline. The population attributable risks for not having 4-5 healthy lifestyle factors were 33% for total deaths, 59% for CVD deaths, and 19% for cancer deaths. CONCLUSIONS In this first study, to our knowledge, to quantify the combined impact of lifestyle-related factors on mortality outcomes in Chinese women, a healthier lifestyle pattern-including being of normal weight, lower central adiposity, participation in physical activity, nonexposure to spousal smoking, and higher fruit and vegetable intake-was associated with reductions in total and cause-specific mortality among lifetime nonsmoking and nondrinking women, supporting the importance of overall lifestyle modification in disease prevention. Please see later in the article for the Editors' Summary."
] |
398 | Exhaustion of B cells contributes to poor Ab response in HIV-infected individuals. | [
"8883846"
] | [
"Antibody-Based HIV-1 Vaccines: Recent Developments and Future Directions. The Global HIV Vaccine Enterprise convened a two-day workshop in May of 2007 to discuss humoral immune responses to HIV and approaches to design vaccines that induce viral neutralizing and other potentially protective antibody responses. The goals of this workshop were to identify key scientific issues, gaps, and opportunities that have emerged since the Enterprise Strategic Plan was first published in 2005 [1], and to make recommendations that Enterprise stakeholders can use to plan new activities. Most effective viral vaccines work, at least in part, by generating antibodies that inactivate or neutralize the invading virus, and the existing data strongly suggest that an optimally effective HIV-1 vaccine should elicit potent antiviral neutralizing antibodies. However, unlike acute viral pathogens, HIV-1 chronically replicates in the host and evades the antibody response. This immune evasion, along with the large genetic variation among HIV-1 strains worldwide, has posed major obstacles to vaccine development. Current HIV vaccine candidates do not elicit neutralizing antibodies against most circulating virus strains, and thus the induction of a protective antibody response remains a major priority for HIV-1 vaccine development. For an antibody-based HIV-1 vaccine, progress in vaccine design is generally gauged by in vitro assays that measure the ability of vaccine-induced antibodies to neutralize a broad spectrum of viral isolates representing the major genetic subtypes (clades) of HIV-1 [2]. Although it is not known what magnitude and breadth of neutralization will predict protection in vaccine recipients, it is clear that current vaccine immunogens elicit antibodies that neutralize only a minority of circulating isolates. Thus, much progress needs to be made in this area. Also, though virus neutralization is considered a critical benchmark for a vaccine, this may not be the only benchmark for predicting success with antibody-based HIV-1 vaccine immunogens. The main targets for neutralizing antibodies to HIV-1 are the surface gp120 and trans-membrane gp41 envelope glycoproteins (Env) that mediate receptor and coreceptor binding and the subsequent membrane fusion events that allow the virus to gain entry into cells [3]. Antibodies neutralize the virus by binding these viral spikes and blocking virus entry into susceptible cells, such as CD4+ T cells [4,5]. In order to chronically replicate in the host, the virus exploits several mechanisms to shield itself against antibody recognition, including a dense outer coating of sugar molecules (N-linked glycans) and the strategic positioning of cysteine–cysteine loop structures on the gp120 molecule [6–8]. These shielding mechanisms, although highly effective, have vulnerabilities imposed by fitness constraints. Information on the precise location and molecular structure of these vulnerable regions could be valuable for the rational design of improved vaccine immunogens. Participants in the workshop identified four areas that, if given proper attention, could provide key information that would bring the field closer to an effective antibody-based HIV-1 vaccine: (1) structure-assisted immunogen design, (2) role of Fc receptors and complement, (3) assay standardization and validation, and (4) immunoregulation of B cell responses."
] |
4 | 1-1% of colorectal cancer patients are diagnosed with regional or distant metastases. | [
"22942787"
] | [
"Relation between Medicare screening reimbursement and stage at diagnosis for older patients with colon cancer.. CONTEXT Medicare's reimbursement policy was changed in 1998 to provide coverage for screening colonoscopies for patients with increased colon cancer risk, and expanded further in 2001 to cover screening colonoscopies for all individuals. OBJECTIVE To determine whether the Medicare reimbursement policy changes were associated with an increase in either colonoscopy use or early stage colon cancer diagnosis. DESIGN, SETTING, AND PARTICIPANTS Patients in the Surveillance, Epidemiology, and End Results Medicare linked database who were 67 years of age and older and had a primary diagnosis of colon cancer during 1992-2002, as well as a group of Medicare beneficiaries who resided in Surveillance, Epidemiology, and End Results areas but who were not diagnosed with cancer. MAIN OUTCOME MEASURES Trends in colonoscopy and sigmoidoscopy use among Medicare beneficiaries without cancer were assessed using multivariate Poisson regression. Among the patients with cancer, stage was classified as early (stage I) vs all other (stages II-IV). Time was categorized as period 1 (no screening coverage, 1992-1997), period 2 (limited coverage, January 1998-June 2001), and period 3 (universal coverage, July 2001-December 2002). A multivariate logistic regression (outcome = early stage) was used to assess temporal trends in stage at diagnosis; an interaction term between tumor site and time was included. RESULTS Colonoscopy use increased from an average rate of 285/100,000 per quarter in period 1 to 889 and 1919/100,000 per quarter in periods 2 (P<.001) and 3 (P vs 2<.001), respectively. During the study period, 44,924 eligible patients were diagnosed with colorectal cancer. The proportion of patients diagnosed at an early stage increased from 22.5% in period 1 to 25.5% in period 2 and 26.3% in period 3 (P<.001 for each pairwise comparison). The changes in Medicare coverage were strongly associated with early stage at diagnosis for patients with proximal colon lesions (adjusted relative risk period 2 vs 1, 1.19; 95% confidence interval, 1.13-1.26; adjusted relative risk period 3 vs 2, 1.10; 95% confidence interval, 1.02-1.17) but weakly associated, if at all, for patients with distal colon lesions (adjusted relative risk period 2 vs 1, 1.07; 95% confidence interval, 1.01-1.13; adjusted relative risk period 3 vs 2, 0.97; 95% confidence interval, 0.90-1.05). CONCLUSIONS Expansion of Medicare reimbursement to cover colon cancer screening was associated with an increased use of colonoscopy for Medicare beneficiaries, and for those who were diagnosed with colon cancer, an increased probability of being diagnosed at an early stage. The selective effect of the coverage change on proximal colon lesions suggests that increased use of whole-colon screening modalities such as colonoscopy may have played a pivotal role."
] |
40 | A diminished ovarian reserve is a very strong indicator of infertility, even in an a priori non-infertile population. | [
"13497630"
] | [
"Association Between Biomarkers of Ovarian Reserve and Infertility Among Older Women of Reproductive Age. Importance Despite lack of evidence of their utility, biomarkers of ovarian reserve are being promoted as potential markers of reproductive potential. Objective To determine the associations between biomarkers of ovarian reserve and reproductive potential among women of late reproductive age. Design, Setting, and Participants Prospective time-to-pregnancy cohort study (2008 to date of last follow-up in March 2016) of women (N = 981) aged 30 to 44 years without a history of infertility who had been trying to conceive for 3 months or less, recruited from the community in the Raleigh-Durham, North Carolina, area. Exposures Early-follicular-phase serum level of antimüllerian hormone (AMH), follicle-stimulating hormone (FSH), and inhibin B and urinary level of FSH. Main Outcomes and Measures The primary outcomes were the cumulative probability of conception by 6 and 12 cycles of attempt and relative fecundability (probability of conception in a given menstrual cycle). Conception was defined as a positive pregnancy test result. Results A total of 750 women (mean age, 33.3 [SD, 3.2] years; 77% white; 36% overweight or obese) provided a blood and urine sample and were included in the analysis. After adjusting for age, body mass index, race, current smoking status, and recent hormonal contraceptive use, women with low AMH values (<0.7 ng/mL [n = 84]) did not have a significantly different predicted probability of conceiving by 6 cycles of attempt (65%; 95% CI, 50%-75%) compared with women (n = 579) with normal values (62%; 95% CI, 57%-66%) or by 12 cycles of attempt (84% [95% CI, 70%-91%] vs 75% [95% CI, 70%-79%], respectively). Women with high serum FSH values (>10 mIU/mL [n = 83]) did not have a significantly different predicted probability of conceiving after 6 cycles of attempt (63%; 95% CI, 50%-73%) compared with women (n = 654) with normal values (62%; 95% CI, 57%-66%) or after 12 cycles of attempt (82% [95% CI, 70%-89%] vs 75% [95% CI, 70%-78%], respectively). Women with high urinary FSH values (>11.5 mIU/mg creatinine [n = 69]) did not have a significantly different predicted probability of conceiving after 6 cycles of attempt (61%; 95% CI, 46%-74%) compared with women (n = 660) with normal values (62%; 95% CI, 58%-66%) or after 12 cycles of attempt (70% [95% CI, 54%-80%] vs 76% [95% CI, 72%-80%], respectively). Inhibin B levels (n = 737) were not associated with the probability of conceiving in a given cycle (hazard ratio per 1-pg/mL increase, 0.999; 95% CI, 0.997-1.001). Conclusions and Relevance Among women aged 30 to 44 years without a history of infertility who had been trying to conceive for 3 months or less, biomarkers indicating diminished ovarian reserve compared with normal ovarian reserve were not associated with reduced fertility. These findings do not support the use of urinary or blood follicle-stimulating hormone tests or antimüllerian hormone levels to assess natural fertility for women with these characteristics."
] |
400 | Exposure to fine particulate air pollution is unrelated to anxiety prevalence. | [
"791050"
] | [
"The relation between past exposure to fine particulate air pollution and prevalent anxiety: observational cohort study. OBJECTIVE To determine whether higher past exposure to particulate air pollution is associated with prevalent high symptoms of anxiety. DESIGN Observational cohort study. SETTING Nurses' Health Study. PARTICIPANTS 71,271 women enrolled in the Nurses' Health Study residing throughout the contiguous United States who had valid estimates on exposure to particulate matter for at least one exposure period of interest and data on anxiety symptoms. MAIN OUTCOME MEASURES Meaningfully high symptoms of anxiety, defined as a score of 6 points or greater on the phobic anxiety subscale of the Crown-Crisp index, administered in 2004. RESULTS The 71,271 eligible women were aged between 57 and 85 years (mean 70 years) at the time of assessment of anxiety symptoms, with a prevalence of high anxiety symptoms of 15%. Exposure to particulate matter was characterized using estimated average exposure to particulate matter <2.5 μm in diameter (PM2.5) and 2.5 to 10 μm in diameter (PM2.5-10) in the one month, three months, six months, one year, and 15 years prior to assessment of anxiety symptoms, and residential distance to the nearest major road two years prior to assessment. Significantly increased odds of high anxiety symptoms were observed with higher exposure to PM2.5 for multiple averaging periods (for example, odds ratio per 10 µg/m(3) increase in prior one month average PM2.5: 1.12, 95% confidence interval 1.06 to 1.19; in prior 12 month average PM2.5: 1.15, 1.06 to 1.26). Models including multiple exposure windows suggested short term averaging periods were more relevant than long term averaging periods. There was no association between anxiety and exposure to PM2.5-10. Residential proximity to major roads was not related to anxiety symptoms in a dose dependent manner. CONCLUSIONS Exposure to fine particulate matter (PM2.5) was associated with high symptoms of anxiety, with more recent exposures potentially more relevant than more distant exposures. Research evaluating whether reductions in exposure to ambient PM2.5 would reduce the population level burden of clinically relevant symptoms of anxiety is warranted."
] |
401 | Expression of MSX2 is induced 3 hours after the addition of BMP4, which is earlier than T and CDX2. | [
"5633876"
] | [
"BRACHYURY and CDX2 Mediate BMP-Induced Differentiation of Human and Mouse Pluripotent Stem Cells into Embryonic and Extraembryonic Lineages. BMP is thought to induce hESC differentiation toward multiple lineages including mesoderm and trophoblast. The BMP-induced trophoblast phenotype is a long-standing paradox in stem cell biology. Here we readdressed BMP function in hESCs and mouse epiblast-derived cells. We found that BMP4 cooperates with FGF2 (via ERK) to induce mesoderm and to inhibit endoderm differentiation. These conditions induced cells with high levels of BRACHYURY (BRA) that coexpressed CDX2. BRA was necessary for and preceded CDX2 expression; both genes were essential for expression not only of mesodermal genes but also of trophoblast-associated genes. Maximal expression of the latter was seen in the absence of FGF but these cells coexpressed mesodermal genes and moreover they differed in cell surface and epigenetic properties from placental trophoblast. We conclude that BMP induces human and mouse pluripotent stem cells primarily to form mesoderm, rather than trophoblast, acting through BRA and CDX2."
] |
403 | Expression of oncolytic virus antigens as peptides makes relapse more likely. | [
"1921218"
] | [
"Detecting and targeting tumor relapse by its resistance to innate effectors at early recurrence. Tumor recurrence represents a major clinical challenge. Our data show that emergent recurrent tumors acquire a phenotype radically different from that of their originating primary tumors. This phenotype allows them to evade a host-derived innate immune response elicited by the progression from minimal residual disease (MRD) to actively growing recurrence. Screening for this innate response predicted accurately in which mice recurrence would occur. Premature induction of recurrence resensitized MRD to the primary therapy, suggesting a possible paradigm shift for clinical treatment of dormant disease in which the current expectant approach is replaced with active attempts to uncover MRD before evolution of the escape phenotype is complete. By combining screening with second-line treatments targeting innate insensitivity, up to 100% of mice that would have otherwise relapsed were cured. These data may open new avenues for early detection and appropriately timed, highly targeted treatment of tumor recurrence irrespective of tumor type or frontline treatment."
] |
404 | Expression of oncolytic virus antigens as peptides permits additional protection against relapse. | [
"1921218"
] | [
"Detecting and targeting tumor relapse by its resistance to innate effectors at early recurrence. Tumor recurrence represents a major clinical challenge. Our data show that emergent recurrent tumors acquire a phenotype radically different from that of their originating primary tumors. This phenotype allows them to evade a host-derived innate immune response elicited by the progression from minimal residual disease (MRD) to actively growing recurrence. Screening for this innate response predicted accurately in which mice recurrence would occur. Premature induction of recurrence resensitized MRD to the primary therapy, suggesting a possible paradigm shift for clinical treatment of dormant disease in which the current expectant approach is replaced with active attempts to uncover MRD before evolution of the escape phenotype is complete. By combining screening with second-line treatments targeting innate insensitivity, up to 100% of mice that would have otherwise relapsed were cured. These data may open new avenues for early detection and appropriately timed, highly targeted treatment of tumor recurrence irrespective of tumor type or frontline treatment."
] |
406 | F4/80+ macrophages regulate mature osteoblast maintenance. | [
"6796297"
] | [
"PDGF-BB secreted by preosteoclasts induces angiogenesis during coupling with osteogenesis. Osteogenesis during bone modeling and remodeling is coupled with angiogenesis. A recent study showed that a specific vessel subtype, strongly positive for CD31 and endomucin (CD31hiEmcnhi), couples angiogenesis and osteogenesis. Here, we found that platelet-derived growth factor-BB (PDGF-BB) secreted by preosteoclasts induces CD31hiEmcnhi vessel formation during bone modeling and remodeling. Mice with depletion of PDGF-BB in the tartrate-resistant acid phosphatase–positive cell lineage show significantly lower trabecular and cortical bone mass, serum and bone marrow PDGF-BB concentrations, and fewer CD31hiEmcnhi vessels compared to wild-type mice. In the ovariectomy (OVX)-induced osteoporotic mouse model, serum and bone marrow levels of PDGF-BB and numbers of CD31hiEmcnhi vessels are significantly lower compared to sham-operated controls. Treatment with exogenous PDGF-BB or inhibition of cathepsin K to increase the number of preosteoclasts, and thus the endogenous levels of PDGF-BB, increases CD31hiEmcnhi vessel number and stimulates bone formation in OVX mice. Thus, pharmacotherapies that increase PDGF-BB secretion from preosteoclasts offer a new therapeutic target for treating osteoporosis by promoting angiogenesis and thus bone formation."
] |
407 | FACT and other histone chaperone(s) compensate for Histone 2A (H2A)-histone 2B (H2B) dimer eviction during the histone exchange process. | [
"9889151"
] | [
"FACT Disrupts Nucleosome Structure by Binding H2A-H2B with Conserved Peptide Motifs.. FACT, a heterodimer of Spt16 and Pob3, is an essential histone chaperone. We show that the H2A-H2B binding activity that is central to FACT function resides in short acidic regions near the C termini of each subunit. Mutations throughout these regions affect binding and cause correlated phenotypes that range from mild to lethal, with the largest individual contributions unexpectedly coming from an aromatic residue and a nearby carboxylate residue within each domain. Spt16 and Pob3 bind overlapping sites on H2A-H2B, and Spt16-Pob3 heterodimers simultaneously bind two H2A-H2B dimers, the same stoichiometry as the components of a nucleosome. An Spt16:H2A-H2B crystal structure explains the biochemical and genetic data, provides a model for Pob3 binding, and implies a mechanism for FACT reorganization that we confirm biochemically. Moreover, unexpected similarity to binding of ANP32E and Swr1 with H2A.Z-H2B reveals that diverse H2A-H2B chaperones use common mechanisms of histone binding and regulating nucleosome functions."
] |
41 | A high microerythrocyte count protects against severe anemia in homozygous alpha (+)- thalassemia trait subjects. | [
"18174210"
] | [
"Increased Microerythrocyte Count in Homozygous α+-Thalassaemia Contributes to Protection against Severe Malarial Anaemia. BACKGROUND The heritable haemoglobinopathy alpha(+)-thalassaemia is caused by the reduced synthesis of alpha-globin chains that form part of normal adult haemoglobin (Hb). Individuals homozygous for alpha(+)-thalassaemia have microcytosis and an increased erythrocyte count. Alpha(+)-thalassaemia homozygosity confers considerable protection against severe malaria, including severe malarial anaemia (SMA) (Hb concentration < 50 g/l), but does not influence parasite count. We tested the hypothesis that the erythrocyte indices associated with alpha(+)-thalassaemia homozygosity provide a haematological benefit during acute malaria. METHODS AND FINDINGS Data from children living on the north coast of Papua New Guinea who had participated in a case-control study of the protection afforded by alpha(+)-thalassaemia against severe malaria were reanalysed to assess the genotype-specific reduction in erythrocyte count and Hb levels associated with acute malarial disease. We observed a reduction in median erythrocyte count of approximately 1.5 x 10(12)/l in all children with acute falciparum malaria relative to values in community children (p < 0.001). We developed a simple mathematical model of the linear relationship between Hb concentration and erythrocyte count. This model predicted that children homozygous for alpha(+)-thalassaemia lose less Hb than children of normal genotype for a reduction in erythrocyte count of >1.1 x 10(12)/l as a result of the reduced mean cell Hb in homozygous alpha(+)-thalassaemia. In addition, children homozygous for alpha(+)-thalassaemia require a 10% greater reduction in erythrocyte count than children of normal genotype (p = 0.02) for Hb concentration to fall to 50 g/l, the cutoff for SMA. We estimated that the haematological profile in children homozygous for alpha(+)-thalassaemia reduces the risk of SMA during acute malaria compared to children of normal genotype (relative risk 0.52; 95% confidence interval [CI] 0.24-1.12, p = 0.09). CONCLUSIONS The increased erythrocyte count and microcytosis in children homozygous for alpha(+)-thalassaemia may contribute substantially to their protection against SMA. A lower concentration of Hb per erythrocyte and a larger population of erythrocytes may be a biologically advantageous strategy against the significant reduction in erythrocyte count that occurs during acute infection with the malaria parasite Plasmodium falciparum. This haematological profile may reduce the risk of anaemia by other Plasmodium species, as well as other causes of anaemia. Other host polymorphisms that induce an increased erythrocyte count and microcytosis may confer a similar advantage."
] |
413 | Female carriers of the Apolipoprotein E4 (APOE4) allele have decreased risk for dementia. | [
"6309659"
] | [
"Reproductive period and risk of dementia in postmenopausal women.. CONTEXT Exogenous estrogen use may lower risk of dementia in postmenopausal women. A relationship between long-term exposure to endogenous estrogens and incident dementia has been hypothesized but not studied. OBJECTIVE To determine whether a longer reproductive period, as an indicator of longer exposure to endogenous estrogens, is associated with lower risk of dementia and Alzheimer disease (AD) in women who have natural menopause. DESIGN AND SETTING The Rotterdam Study, a population-based prospective cohort study conducted in the Netherlands. PARTICIPANTS A total of 3601 women aged 55 years or older who did not have dementia at baseline (1990-1993) and had information on age at menarche, age at menopause, and type of menopause. Participants were reexamined in 1993-1994 and 1997-1999 and were continuously monitored for development of dementia. MAIN OUTCOME MEASURES Incidence of dementia, based on Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition criteria, and AD, based on National Institute of Neurological Disorders and Stroke/Alzheimer's Disease and Related Disorders Association criteria, compared by quartiles of reproductive period among women with natural menopause. RESULTS During 21 046 person-years of follow-up (median follow-up, 6.3 years), 199 women developed dementia, including 159 who developed AD. After adjusting for age, dementia was not clearly associated with length of reproductive period. However, after adjusting for multiple covariates, women with natural menopause and more reproductive years had an increased risk of dementia (adjusted rate ratio [RR] for women with >39 reproductive years [highest quartile] compared with <34 reproductive years [lowest quartile], 1.78; 95% confidence interval [CI], 1.12-2.84). The adjusted RR per year of increase was 1.04 (95% CI, 1.01-1.08). For risk of AD, the adjusted RRs were 1.51 (95% CI, 0.91-2.50) and 1.03 (95% CI, 1.00-1.07), respectively. Risk of dementia associated with a longer reproductive period was most pronounced in APOE epsilon4 carriers (adjusted RR for >39 reproductive years compared with <34 reproductive years, 4.20 [95% CI, 1.97-8.92] for dementia and 3.42 [95% CI, 1.51-7.75] for AD), whereas in noncarriers, no clear association with dementia or AD was observed. CONCLUSION Our findings do not support the hypothesis that a longer reproductive period reduces risk of dementia in women who have natural menopause."
] |
414 | Female carriers of the Apolipoprotein E4 (APOE4) allele have increased risk for Alzheimer's disease. | [
"6309659"
] | [
"Reproductive period and risk of dementia in postmenopausal women.. CONTEXT Exogenous estrogen use may lower risk of dementia in postmenopausal women. A relationship between long-term exposure to endogenous estrogens and incident dementia has been hypothesized but not studied. OBJECTIVE To determine whether a longer reproductive period, as an indicator of longer exposure to endogenous estrogens, is associated with lower risk of dementia and Alzheimer disease (AD) in women who have natural menopause. DESIGN AND SETTING The Rotterdam Study, a population-based prospective cohort study conducted in the Netherlands. PARTICIPANTS A total of 3601 women aged 55 years or older who did not have dementia at baseline (1990-1993) and had information on age at menarche, age at menopause, and type of menopause. Participants were reexamined in 1993-1994 and 1997-1999 and were continuously monitored for development of dementia. MAIN OUTCOME MEASURES Incidence of dementia, based on Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition criteria, and AD, based on National Institute of Neurological Disorders and Stroke/Alzheimer's Disease and Related Disorders Association criteria, compared by quartiles of reproductive period among women with natural menopause. RESULTS During 21 046 person-years of follow-up (median follow-up, 6.3 years), 199 women developed dementia, including 159 who developed AD. After adjusting for age, dementia was not clearly associated with length of reproductive period. However, after adjusting for multiple covariates, women with natural menopause and more reproductive years had an increased risk of dementia (adjusted rate ratio [RR] for women with >39 reproductive years [highest quartile] compared with <34 reproductive years [lowest quartile], 1.78; 95% confidence interval [CI], 1.12-2.84). The adjusted RR per year of increase was 1.04 (95% CI, 1.01-1.08). For risk of AD, the adjusted RRs were 1.51 (95% CI, 0.91-2.50) and 1.03 (95% CI, 1.00-1.07), respectively. Risk of dementia associated with a longer reproductive period was most pronounced in APOE epsilon4 carriers (adjusted RR for >39 reproductive years compared with <34 reproductive years, 4.20 [95% CI, 1.97-8.92] for dementia and 3.42 [95% CI, 1.51-7.75] for AD), whereas in noncarriers, no clear association with dementia or AD was observed. CONCLUSION Our findings do not support the hypothesis that a longer reproductive period reduces risk of dementia in women who have natural menopause."
] |
416 | Female carriers of the Apolipoprotein E4 (APOE4) allele have longer lifetime exposure to estrogen due to an increased reproductive period. | [
"6309659"
] | [
"Reproductive period and risk of dementia in postmenopausal women.. CONTEXT Exogenous estrogen use may lower risk of dementia in postmenopausal women. A relationship between long-term exposure to endogenous estrogens and incident dementia has been hypothesized but not studied. OBJECTIVE To determine whether a longer reproductive period, as an indicator of longer exposure to endogenous estrogens, is associated with lower risk of dementia and Alzheimer disease (AD) in women who have natural menopause. DESIGN AND SETTING The Rotterdam Study, a population-based prospective cohort study conducted in the Netherlands. PARTICIPANTS A total of 3601 women aged 55 years or older who did not have dementia at baseline (1990-1993) and had information on age at menarche, age at menopause, and type of menopause. Participants were reexamined in 1993-1994 and 1997-1999 and were continuously monitored for development of dementia. MAIN OUTCOME MEASURES Incidence of dementia, based on Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition criteria, and AD, based on National Institute of Neurological Disorders and Stroke/Alzheimer's Disease and Related Disorders Association criteria, compared by quartiles of reproductive period among women with natural menopause. RESULTS During 21 046 person-years of follow-up (median follow-up, 6.3 years), 199 women developed dementia, including 159 who developed AD. After adjusting for age, dementia was not clearly associated with length of reproductive period. However, after adjusting for multiple covariates, women with natural menopause and more reproductive years had an increased risk of dementia (adjusted rate ratio [RR] for women with >39 reproductive years [highest quartile] compared with <34 reproductive years [lowest quartile], 1.78; 95% confidence interval [CI], 1.12-2.84). The adjusted RR per year of increase was 1.04 (95% CI, 1.01-1.08). For risk of AD, the adjusted RRs were 1.51 (95% CI, 0.91-2.50) and 1.03 (95% CI, 1.00-1.07), respectively. Risk of dementia associated with a longer reproductive period was most pronounced in APOE epsilon4 carriers (adjusted RR for >39 reproductive years compared with <34 reproductive years, 4.20 [95% CI, 1.97-8.92] for dementia and 3.42 [95% CI, 1.51-7.75] for AD), whereas in noncarriers, no clear association with dementia or AD was observed. CONCLUSION Our findings do not support the hypothesis that a longer reproductive period reduces risk of dementia in women who have natural menopause."
] |
417 | Female carriers of the Apolipoprotein E4 (APOE4) allele have shorter lifetime exposure to estrogen due to a decreased reproductive period. | [
"6309659"
] | [
"Reproductive period and risk of dementia in postmenopausal women.. CONTEXT Exogenous estrogen use may lower risk of dementia in postmenopausal women. A relationship between long-term exposure to endogenous estrogens and incident dementia has been hypothesized but not studied. OBJECTIVE To determine whether a longer reproductive period, as an indicator of longer exposure to endogenous estrogens, is associated with lower risk of dementia and Alzheimer disease (AD) in women who have natural menopause. DESIGN AND SETTING The Rotterdam Study, a population-based prospective cohort study conducted in the Netherlands. PARTICIPANTS A total of 3601 women aged 55 years or older who did not have dementia at baseline (1990-1993) and had information on age at menarche, age at menopause, and type of menopause. Participants were reexamined in 1993-1994 and 1997-1999 and were continuously monitored for development of dementia. MAIN OUTCOME MEASURES Incidence of dementia, based on Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition criteria, and AD, based on National Institute of Neurological Disorders and Stroke/Alzheimer's Disease and Related Disorders Association criteria, compared by quartiles of reproductive period among women with natural menopause. RESULTS During 21 046 person-years of follow-up (median follow-up, 6.3 years), 199 women developed dementia, including 159 who developed AD. After adjusting for age, dementia was not clearly associated with length of reproductive period. However, after adjusting for multiple covariates, women with natural menopause and more reproductive years had an increased risk of dementia (adjusted rate ratio [RR] for women with >39 reproductive years [highest quartile] compared with <34 reproductive years [lowest quartile], 1.78; 95% confidence interval [CI], 1.12-2.84). The adjusted RR per year of increase was 1.04 (95% CI, 1.01-1.08). For risk of AD, the adjusted RRs were 1.51 (95% CI, 0.91-2.50) and 1.03 (95% CI, 1.00-1.07), respectively. Risk of dementia associated with a longer reproductive period was most pronounced in APOE epsilon4 carriers (adjusted RR for >39 reproductive years compared with <34 reproductive years, 4.20 [95% CI, 1.97-8.92] for dementia and 3.42 [95% CI, 1.51-7.75] for AD), whereas in noncarriers, no clear association with dementia or AD was observed. CONCLUSION Our findings do not support the hypothesis that a longer reproductive period reduces risk of dementia in women who have natural menopause."
] |
418 | Fibroblast Growth Factor is a ligand which signals through receptor tyrosine kinases. | [
"16660256"
] | [
"Sprouty1 Regulates Reversible Quiescence of a Self-Renewing Adult Muscle Stem Cell Pool during Regeneration. Satellite cells are skeletal muscle stem cells capable of self-renewal and differentiation after transplantation, but whether they contribute to endogenous muscle fiber repair has been unclear. The transcription factor Pax7 marks satellite cells and is critical for establishing the adult satellite cell pool. By using a lineage tracing approach, we show that after injury, quiescent adult Pax7(+) cells enter the cell cycle; a subpopulation returns to quiescence to replenish the satellite cell compartment, while others contribute to muscle fiber formation. We demonstrate that Sprouty1 (Spry1), a receptor tyrosine kinase signaling inhibitor, is expressed in quiescent Pax7(+) satellite cells in uninjured muscle, downregulated in proliferating myogenic cells after injury, and reinduced as Pax7(+) cells re-enter quiescence. We show that Spry1 is required for the return to quiescence and homeostasis of the satellite cell pool during repair. Our results therefore define a role for Spry1 in adult muscle stem cell biology and tissue repair."
] |
420 | Fibroblast growth factor 21 protects against atherosclerosis by modulating adiponectin and SREBP2 levels. | [
"9315213"
] | [
"Fibroblast Growth Factor 21 Prevents Atherosclerosis by Suppression of Hepatic Sterol Regulatory Element-Binding Protein-2 and Induction of Adiponectin in Mice. BACKGROUND Fibroblast growth factor 21 (FGF21) is a metabolic hormone with pleiotropic effects on glucose and lipid metabolism and insulin sensitivity. It acts as a key downstream target of both peroxisome proliferator-activated receptor α and γ, the agonists of which have been used for lipid lowering and insulin sensitization, respectively. However, the role of FGF21 in the cardiovascular system remains elusive. METHODS AND RESULTS The roles of FGF21 in atherosclerosis were investigated by evaluating the impact of FGF21 deficiency and replenishment with recombinant FGF21 in apolipoprotein E(-/-) mice. FGF21 deficiency causes a marked exacerbation of atherosclerotic plaque formation and premature death in apolipoprotein E(-/-) mice, which is accompanied by hypoadiponectinemia and severe hypercholesterolemia. Replenishment of FGF21 protects against atherosclerosis in apolipoprotein E(-/-)mice via 2 independent mechanisms, inducing the adipocyte production of adiponectin, which in turn acts on the blood vessels to inhibit neointima formation and macrophage inflammation, and suppressing the hepatic expression of the transcription factor sterol regulatory element-binding protein-2, thereby leading to reduced cholesterol synthesis and attenuation of hypercholesterolemia. Chronic treatment with adiponectin partially reverses atherosclerosis without obvious effects on hypercholesterolemia in FGF21-deficient apolipoprotein E(-/-) mice. By contrast, the cholesterol-lowering effects of FGF21 are abrogated by hepatic expression of sterol regulatory element-binding protein-2. CONCLUSIONS FGF21 protects against atherosclerosis via fine tuning the multiorgan crosstalk among liver, adipose tissue, and blood vessels."
] |
422 | Flexible molecules experience less steric hindrance in the tumor microenviroment than rigid molecules. | [
"11172205"
] | [
"Quantum dots spectrally distinguish multiple species within the tumor milieu in vivo. A solid tumor is an organ composed of cancer and host cells embedded in an extracellular matrix and nourished by blood vessels. A prerequisite to understanding tumor pathophysiology is the ability to distinguish and monitor each component in dynamic studies. Standard fluorophores hamper simultaneous intravital imaging of these components. Here, we used multiphoton microscopy techniques and transgenic mice that expressed green fluorescent protein, and combined them with the use of quantum dot preparations. We show that these fluorescent semiconductor nanocrystals can be customized to concurrently image and differentiate tumor vessels from both the perivascular cells and the matrix. Moreover, we used them to measure the ability of particles of different sizes to access the tumor. Finally, we successfully monitored the recruitment of quantum dot–labeled bone marrow–derived precursor cells to the tumor vasculature. These examples show the versatility of quantum dots for studying tumor pathophysiology and creating avenues for treatment."
] |
423 | Folate and vitamin B12 levels influence the association between homocysteine and preeclampsia. | [
"8595678"
] | [
"Effect modification by population dietary folate on the association between MTHFR genotype, homocysteine, and stroke risk: a meta-analysis of genetic studies and randomised trials. BACKGROUND The MTHFR 677C→T polymorphism has been associated with raised homocysteine concentration and increased risk of stroke. A previous overview showed that the effects were greatest in regions with low dietary folate consumption, but differentiation between the effect of folate and small-study bias was difficult. A meta-analysis of randomised trials of homocysteine-lowering interventions showed no reduction in coronary heart disease events or stroke, but the trials were generally set in populations with high folate consumption. We aimed to reduce the effect of small-study bias and investigate whether folate status modifies the association between MTHFR 677C→T and stroke in a genetic analysis and meta-analysis of randomised controlled trials. METHODS We established a collaboration of genetic studies consisting of 237 datasets including 59,995 individuals with data for homocysteine and 20,885 stroke events. We compared the genetic findings with a meta-analysis of 13 randomised trials of homocysteine-lowering treatments and stroke risk (45,549 individuals, 2314 stroke events, 269 transient ischaemic attacks). FINDINGS The effect of the MTHFR 677C→T variant on homocysteine concentration was larger in low folate regions (Asia; difference between individuals with TT versus CC genotype, 3·12 μmol/L, 95% CI 2·23 to 4·01) than in areas with folate fortification (America, Australia, and New Zealand, high; 0·13 μmol/L, -0·85 to 1·11). The odds ratio (OR) for stroke was also higher in Asia (1·68, 95% CI 1·44 to 1·97) than in America, Australia, and New Zealand, high (1·03, 0·84 to 1·25). Most randomised trials took place in regions with high or increasing population folate concentrations. The summary relative risk (RR) of stroke in trials of homocysteine-lowering interventions (0·94, 95% CI 0·85 to 1·04) was similar to that predicted for the same extent of homocysteine reduction in large genetic studies in populations with similar folate status (predicted RR 1·00, 95% CI 0·90 to 1·11). Although the predicted effect of homocysteine reduction from large genetic studies in low folate regions (Asia) was larger (RR 0·78, 95% CI 0·68 to 0·90), no trial has evaluated the effect of lowering of homocysteine on stroke risk exclusively in a low folate region. INTERPRETATION In regions with increasing levels or established policies of population folate supplementation, evidence from genetic studies and randomised trials is concordant in suggesting an absence of benefit from lowering of homocysteine for prevention of stroke. Further large-scale genetic studies of the association between MTHFR 677C→T and stroke in low folate settings are needed to distinguish effect modification by folate from small-study bias. If future randomised trials of homocysteine-lowering interventions for stroke prevention are undertaken, they should take place in regions with low folate consumption. FUNDING Full funding sources listed at end of paper (see Acknowledgments)."
] |
425 | For every 1,000 children with cerebral palsy, more than 300 of them are premature or underweight at birth. | [
"33257464"
] | [
"Changes in the prevalence of cerebral palsy for children born very prematurely within a population-based program over 30 years.. CONTEXT Although cerebral palsy (CP) among extremely premature infants has been reported as a major morbidity outcome, there are difficulties comparing published CP rates from many sites over various birth years. OBJECTIVE To assess the changes in population-based, gestational age-specific prevalence rates of CP among extremely premature infants over 30 years. DESIGN Prospective population-based longitudinal outcome study. SETTING AND PARTICIPANTS In Northern Alberta, 2318 infants 20 to 27 weeks' gestational age with birth weights of 500 to 1249 g were liveborn from 1974 through 2003. By 2 years of age, 1437 (62%) had died, 23 (1%) were lost to follow-up, and 858 (37%) had received multidisciplinary neurodevelopmental assessment. MAIN OUTCOME MEASURE Population-based prevalence rates of CP were determined. Logistic regression with linear spline was used to assess changes in CP prevalence over time. RESULTS At age 2 years, 122 (14.2%) of 858 survivors had CP. This diagnosis was confirmed for each child by age 3 years or older. Among those whose gestational age was 20 to 25 weeks, population-based survival increased from 4% to 31% (P<.001), while CP prevalence per 1000 live births increased monotonically from 0 to 110 until the years 1992-1994 (P<.001) and decreased thereafter to 22 in the years 2001-2003 (P<.001). Among those whose gestational age was 26 to 27 weeks, population-based survival increased from 23% to between 75% and 80% (P<.001), while CP prevalence per 1000 live births increased monotonically from 15 to 155 until the years 1992-1994 (P<.001) and then decreased to 16 in the years 2001-2003 (P<.001). For all survivors born in the years 2001-2003, CP prevalence was 19 per 1000 live births. CONCLUSION Population-based CP prevalence rates for children whose gestational age was 20 to 27 weeks and whose birth weight ranged from 500 to 1249 g show steady reductions in the last decade with stable or reducing mortality, reversing trends prior to 1992-1994."
] |
426 | Forkhead 0 (fox0) transcription factors are involved in apoptosis. | [
"16728949"
] | [
"Cell Stem Cell Review FoxO Transcription Factors and Stem Cell Homeostasis: Insights from the Hematopoietic System. The forkhead O (FoxO) family of transcription factors participates in diverse physiologic processes, including induction of cell-cycle arrest, stress resistance, differentiation, apoptosis, and metabolism. Several recent studies indicate that FoxO-dependent signaling is required for long-term regenerative potential of the hematopoietic stem cell (HSC) compartment through regulation of HSC response to physiologic oxidative stress, quiescence, and survival. These observations link FoxO function in mammalian systems with the evolutionarily conserved role of FoxO in promotion of stress resistance and longevity in lower phylogenetic systems. Furthermore, these findings have implications for aging in higher organisms and in malignant stem cell biology, and suggest that FoxOs may play an important role in the maintenance and integrity of stem cell compartments in a broad spectrum of tissues."
] |
428 | Forkhead 0 (fox0) transcription factors are involved in cellular differentiation. | [
"16728949"
] | [
"Cell Stem Cell Review FoxO Transcription Factors and Stem Cell Homeostasis: Insights from the Hematopoietic System. The forkhead O (FoxO) family of transcription factors participates in diverse physiologic processes, including induction of cell-cycle arrest, stress resistance, differentiation, apoptosis, and metabolism. Several recent studies indicate that FoxO-dependent signaling is required for long-term regenerative potential of the hematopoietic stem cell (HSC) compartment through regulation of HSC response to physiologic oxidative stress, quiescence, and survival. These observations link FoxO function in mammalian systems with the evolutionarily conserved role of FoxO in promotion of stress resistance and longevity in lower phylogenetic systems. Furthermore, these findings have implications for aging in higher organisms and in malignant stem cell biology, and suggest that FoxOs may play an important role in the maintenance and integrity of stem cell compartments in a broad spectrum of tissues."
] |
429 | Formation of N-terminal pyroglutamate by glutamine cyclase (GC) competes with NTAQ1 for Nt-Gln substrates. | [
"36540079"
] | [
"Glutamine-specific N-terminal amidase, a component of the N-end rule pathway.. Deamidation of N-terminal Gln by Nt(Q)-amidase, an N-terminal amidohydrolase, is a part of the N-end rule pathway of protein degradation. We detected the activity of Nt(Q)-amidase, termed Ntaq1, in mouse tissues, purified Ntaq1 from bovine brains, identified its gene, and began analyzing this enzyme. Ntaq1 is highly conserved among animals, plants, and some fungi, but its sequence is dissimilar to sequences of other amidases. An earlier mutant in the Drosophila Cg8253 gene that we show here to encode Nt(Q)-amidase has defective long-term memory. Other studies identified protein ligands of the uncharacterized human C8orf32 protein that we show here to be the Ntaq1 Nt(Q)-amidase. Remarkably, \"high-throughput\" studies have recently solved the crystal structure of C8orf32 (Ntaq1). Our site-directed mutagenesis of Ntaq1 and its crystal structure indicate that the active site and catalytic mechanism of Nt(Q)-amidase are similar to those of transglutaminases."
] |
43 | A low percentage of hematopoietic progenitor cells are susceptible to HIV-1 infection ex vivo. | [
"7224723"
] | [
"HIV–1 Infects Multipotent Progenitor Cells Causing Cell Death and Establishing Latent Cellular Reservoirs. HIV causes a chronic infection characterized by depletion of CD4(+) T lymphocytes and the development of opportunistic infections. Despite drugs that inhibit viral spread, HIV infection has been difficult to cure because of uncharacterized reservoirs of infected cells that are resistant to highly active antiretroviral therapy (HAART) and the immune response. Here we used CD34(+) cells from infected people as well as in vitro studies of wild-type HIV to show infection and killing of CD34(+) multipotent hematopoietic progenitor cells (HPCs). In some HPCs, we detected latent infection that stably persisted in cell culture until viral gene expression was activated by differentiation factors. A unique reporter HIV that directly detects latently infected cells in vitro confirmed the presence of distinct populations of active and latently infected HPCs. These findings have major implications for understanding HIV bone marrow pathology and the mechanisms by which HIV causes persistent infection."
] |
430 | FoxO3a activation in neuronal death is inhibited by reactive oxygen species (ROS). | [
"28937856"
] | [
"Stress-dependent regulation of FOXO transcription factors by the SIRT1 deacetylase.. The Sir2 deacetylase modulates organismal life-span in various species. However, the molecular mechanisms by which Sir2 increases longevity are largely unknown. We show that in mammalian cells, the Sir2 homolog SIRT1 appears to control the cellular response to stress by regulating the FOXO family of Forkhead transcription factors, a family of proteins that function as sensors of the insulin signaling pathway and as regulators of organismal longevity. SIRT1 and the FOXO transcription factor FOXO3 formed a complex in cells in response to oxidative stress, and SIRT1 deacetylated FOXO3 in vitro and within cells. SIRT1 had a dual effect on FOXO3 function: SIRT1 increased FOXO3's ability to induce cell cycle arrest and resistance to oxidative stress but inhibited FOXO3's ability to induce cell death. Thus, one way in which members of the Sir2 family of proteins may increase organismal longevity is by tipping FOXO-dependent responses away from apoptosis and toward stress resistance."
] |
432 | Foxk2 regulates autophagy genes in muscle cells and fibroblast cells. | [
"8002887"
] | [
"Foxk proteins repress the initiation of starvation-induced atrophy and autophagy programs. Autophagy is the primary catabolic process triggered in response to starvation. Although autophagic regulation within the cytosolic compartment is well established, it is becoming clear that nuclear events also regulate the induction or repression of autophagy. Nevertheless, a thorough understanding of the mechanisms by which sequence-specific transcription factors modulate expression of genes required for autophagy is lacking. Here, we identify Foxk proteins (Foxk1 and Foxk2) as transcriptional repressors of autophagy in muscle cells and fibroblasts. Interestingly, Foxk1/2 serve to counter-balance another forkhead transcription factor, Foxo3, which induces an overlapping set of autophagic and atrophic targets in muscle. Foxk1/2 specifically recruits Sin3A-HDAC complexes to restrict acetylation of histone H4 and expression of critical autophagy genes. Remarkably, mTOR promotes the transcriptional activity of Foxk1 by facilitating nuclear entry to specifically limit basal levels of autophagy in nutrient-rich conditions. Our study highlights an ancient, conserved mechanism whereby nutritional status is interpreted by mTOR to restrict autophagy by repressing essential autophagy genes through Foxk-Sin3-mediated transcriptional control."
] |
434 | Foxp3 enables the expression of transcriptional regulators implicated in memory T cell development. | [
"9500590"
] | [
"Extrathymic Generation of Regulatory T Cells in Placental Mammals Mitigates Maternal-Fetal Conflict. Regulatory T (Treg) cells, whose differentiation and function are controlled by X chromosome-encoded transcription factor Foxp3, are generated in the thymus (tTreg) and extrathymically (peripheral, pTreg), and their deficiency results in fatal autoimmunity. Here, we demonstrate that a Foxp3 enhancer, conserved noncoding sequence 1 (CNS1), essential for pTreg but dispensable for tTreg cell generation, is present only in placental mammals. CNS1 is largely composed of mammalian-wide interspersed repeats (MIR) that have undergone retrotransposition during early mammalian radiation. During pregnancy, pTreg cells specific to a model paternal alloantigen were generated in a CNS1-dependent manner and accumulated in the placenta. Furthermore, when mated with allogeneic, but not syngeneic, males, CNS1-deficient females showed increased fetal resorption accompanied by increased immune cell infiltration and defective remodeling of spiral arteries. Our results suggest that, during evolution, a CNS1-dependent mechanism of extrathymic differentiation of Treg cells emerged in placental animals to enforce maternal-fetal tolerance."
] |
435 | Foxp3 represses the expression of transcriptional regulators implicated in memory T cell development. | [
"9500590"
] | [
"Extrathymic Generation of Regulatory T Cells in Placental Mammals Mitigates Maternal-Fetal Conflict. Regulatory T (Treg) cells, whose differentiation and function are controlled by X chromosome-encoded transcription factor Foxp3, are generated in the thymus (tTreg) and extrathymically (peripheral, pTreg), and their deficiency results in fatal autoimmunity. Here, we demonstrate that a Foxp3 enhancer, conserved noncoding sequence 1 (CNS1), essential for pTreg but dispensable for tTreg cell generation, is present only in placental mammals. CNS1 is largely composed of mammalian-wide interspersed repeats (MIR) that have undergone retrotransposition during early mammalian radiation. During pregnancy, pTreg cells specific to a model paternal alloantigen were generated in a CNS1-dependent manner and accumulated in the placenta. Furthermore, when mated with allogeneic, but not syngeneic, males, CNS1-deficient females showed increased fetal resorption accompanied by increased immune cell infiltration and defective remodeling of spiral arteries. Our results suggest that, during evolution, a CNS1-dependent mechanism of extrathymic differentiation of Treg cells emerged in placental animals to enforce maternal-fetal tolerance."
] |
44 | A mutation in HNF4A leads to an increased risk of developing diabetes by the age of 14 years. | [
"56893404"
] | [
"Macrosomia and Hyperinsulinaemic Hypoglycaemia in Patients with Heterozygous Mutations in the HNF4A Gene. Background Macrosomia is associated with considerable neonatal and maternal morbidity. Factors that predict macrosomia are poorly understood. The increased rate of macrosomia in the offspring of pregnant women with diabetes and in congenital hyperinsulinaemia is mediated by increased foetal insulin secretion. We assessed the in utero and neonatal role of two key regulators of pancreatic insulin secretion by studying birthweight and the incidence of neonatal hypoglycaemia in patients with heterozygous mutations in the maturity-onset diabetes of the young (MODY) genes HNF4A (encoding HNF-4α) and HNF1A/TCF1 (encoding HNF-1α), and the effect of pancreatic deletion of Hnf4a on foetal and neonatal insulin secretion in mice."
] |
441 | G-CSF increases the expansion and infiltration of MDSCs into tumors. | [
"2014909"
] | [
"Oncogenic mTOR signaling recruits myeloid-derived suppressor cells to promote tumor initiation. Myeloid-derived suppressor cells (MDSCs) play critical roles in primary and metastatic cancer progression. MDSC regulation is widely variable even among patients harbouring the same type of malignancy, and the mechanisms governing such heterogeneity are largely unknown. Here, integrating human tumour genomics and syngeneic mammary tumour models, we demonstrate that mTOR signalling in cancer cells dictates a mammary tumour's ability to stimulate MDSC accumulation through regulating G-CSF. Inhibiting this pathway or its activators (for example, FGFR) impairs tumour progression, which is partially rescued by restoring MDSCs or G-CSF. Tumour-initiating cells (TICs) exhibit elevated G-CSF. MDSCs reciprocally increase TIC frequency through activating Notch in tumour cells, forming a feedforward loop. Analyses of primary breast cancers and patient-derived xenografts corroborate these mechanisms in patients. These findings establish a non-canonical oncogenic role of mTOR signalling in recruiting pro-tumorigenic MDSCs and show how defined cancer subsets may evolve to promote and depend on a distinct immune microenvironment."
] |
444 | GATA3 regulates cell cycle progression in bone marrow hematopoietic stem cells. | [
"10165258"
] | [
"GATA-3 regulates hematopoietic stem cell maintenance and cell-cycle entry.. Maintaining hematopoietic stem cell (HSC) quiescence is a critical property for the life-long generation of blood cells. Approximately 75% of cells in a highly enriched long-term repopulating HSC (LT-HSC) pool (Lin(-)Sca1(+)c-Kit(hi)CD150(+)CD48(-)) are quiescent, with only a small percentage of the LT-HSCs in cycle. Transcription factor GATA-3 is known to be vital for the development of T cells at multiple stages in the thymus and for Th2 differentiation in the peripheral organs. Although it is well documented that GATA-3 is expressed in HSCs, a role for GATA-3 in any prethymic progenitor cell has not been established. In the present study, we show that Gata3-null mutant mice generate fewer LT-HSCs and that fewer Gata3-null LT-HSCs are in cycle. Furthermore, Gata3 mutant hematopoietic progenitor cells fail to be recruited into an increased cycling state after 5-fluorouracil-induced myelosuppression. Therefore, GATA-3 is required for the maintenance of a normal number of LT-HSCs and for their entry into the cell cycle."
] |
445 | GATA3 regulates self-renewal capacity in bone marrow hematopoietic stem cells. | [
"10165258"
] | [
"GATA-3 regulates hematopoietic stem cell maintenance and cell-cycle entry.. Maintaining hematopoietic stem cell (HSC) quiescence is a critical property for the life-long generation of blood cells. Approximately 75% of cells in a highly enriched long-term repopulating HSC (LT-HSC) pool (Lin(-)Sca1(+)c-Kit(hi)CD150(+)CD48(-)) are quiescent, with only a small percentage of the LT-HSCs in cycle. Transcription factor GATA-3 is known to be vital for the development of T cells at multiple stages in the thymus and for Th2 differentiation in the peripheral organs. Although it is well documented that GATA-3 is expressed in HSCs, a role for GATA-3 in any prethymic progenitor cell has not been established. In the present study, we show that Gata3-null mutant mice generate fewer LT-HSCs and that fewer Gata3-null LT-HSCs are in cycle. Furthermore, Gata3 mutant hematopoietic progenitor cells fail to be recruited into an increased cycling state after 5-fluorouracil-induced myelosuppression. Therefore, GATA-3 is required for the maintenance of a normal number of LT-HSCs and for their entry into the cell cycle."
] |
447 | Gastric infection with Helicobacter pylori decreases risk of gastric cancer in humans. | [
"2052720"
] | [
"Association between infection with Helicobacter pylori and risk of gastric cancer: evidence from a prospective investigation.. OBJECTIVE To investigate the association between gastric cancer and prior infection with Helicobacter pylori. DESIGN Case-control comparison of prevalence of IgG antibodies to H pylori in blood samples collected prospectively, before diagnosis of gastric cancer in the cases. Presence of H pylori antibody (greater than 10 micrograms IgG/ml) determined by enzyme linked immunosorbent assay (ELISA). SUBJECTS 29 men with a subsequent diagnosis of gastric cancer and 116 aged matched controls selected from over 22,000 middle aged men participating in two ongoing cohort studies (the British United Provident Association study and the Caerphilly collaborative heart disease study), who had provided blood samples during 1975-1982. RESULTS 20 of the 29 cases (69%) and 54 of the 116 controls (47%) were positive for H pylori specific antibody. The median specific IgG concentration was significantly higher in the cases than controls (90 micrograms/ml v 3.6 micrograms/ml, p less than 0.01). The estimated odds ratio for the risk of gastric cancer in those with a history of infection with H pylori was 2.77 (95% confidence interval 1.04 to 7.97, 2p = 0.039). CONCLUSIONS H pylori infection may be an important cause of gastric cancer; between 35% and 55% of all cases may be associated with such an infection."
] |
448 | Gastric infection with Helicobacter pylori increases risk of gastric cancer in humans. | [
"2052720"
] | [
"Association between infection with Helicobacter pylori and risk of gastric cancer: evidence from a prospective investigation.. OBJECTIVE To investigate the association between gastric cancer and prior infection with Helicobacter pylori. DESIGN Case-control comparison of prevalence of IgG antibodies to H pylori in blood samples collected prospectively, before diagnosis of gastric cancer in the cases. Presence of H pylori antibody (greater than 10 micrograms IgG/ml) determined by enzyme linked immunosorbent assay (ELISA). SUBJECTS 29 men with a subsequent diagnosis of gastric cancer and 116 aged matched controls selected from over 22,000 middle aged men participating in two ongoing cohort studies (the British United Provident Association study and the Caerphilly collaborative heart disease study), who had provided blood samples during 1975-1982. RESULTS 20 of the 29 cases (69%) and 54 of the 116 controls (47%) were positive for H pylori specific antibody. The median specific IgG concentration was significantly higher in the cases than controls (90 micrograms/ml v 3.6 micrograms/ml, p less than 0.01). The estimated odds ratio for the risk of gastric cancer in those with a history of infection with H pylori was 2.77 (95% confidence interval 1.04 to 7.97, 2p = 0.039). CONCLUSIONS H pylori infection may be an important cause of gastric cancer; between 35% and 55% of all cases may be associated with such an infection."
] |
449 | Gastric lavage is an effective treatment for acute paraquat poisoning. | [
"12209494",
"3430789"
] | [
"Multiple-dose activated charcoal in acute self-poisoning: a randomised controlled trial. BACKGROUND The case-fatality for intentional self-poisoning in the rural developing world is 10-50-fold higher than that in industrialised countries, mostly because of the use of highly toxic pesticides and plants. We therefore aimed to assess whether routine treatment with multiple-dose activated charcoal, to interrupt enterovascular or enterohepatic circulations, offers benefit compared with no charcoal in such an environment. METHODS We did an open-label, parallel group, randomised, controlled trial of six 50 g doses of activated charcoal at 4-h intervals versus no charcoal versus one 50 g dose of activated charcoal in three Sri Lankan hospitals. 4632 patients were randomised to receive no charcoal (n=1554), one dose of charcoal (n=1545), or six doses of charcoal (n=1533); outcomes were available for 4629 patients. 2338 (51%) individuals had ingested pesticides, whereas 1647 (36%) had ingested yellow oleander (Thevetia peruviana) seeds. Mortality was the primary outcome measure. Analysis was by intention to treat. The trial is registered with controlled-trials.com as ISRCTN02920054. FINDINGS Mortality did not differ between the groups. 97 (6.3%) of 1531 participants in the multiple-dose group died, compared with 105 (6.8%) of 1554 in the no charcoal group (adjusted odds ratio 0.96, 95% CI 0.70-1.33). No differences were noted for patients who took particular poisons, were severely ill on admission, or who presented early. INTERPRETATION We cannot recommend the routine use of multiple-dose activated charcoal in rural Asia Pacific; although further studies of early charcoal administration might be useful, effective affordable treatments are urgently needed.",
"Effect of activated charcoal hemoperfusion on renal function in patients with paraquat poisoning.. The present study retrospectively analyzed 19 patients diagnosed with paraquat (PQ) poisoning with the aim to investigate the effect of activated charcoal hemoperfusion on renal function and PQ elimination. The results indicated that 7 patients died and 12 survived. Non-oliguric renal failure occurred in all of the 7 patients who died. Among the 12 surviving patients, 10 had normal renal function and 2 developed non-oliguric renal failure. There was a linear correlation between plasma and urine paraquat concentration prior to and during activated charcoal hemoperfusion. The equation parameters together with the correlation coefficient on admission were as follows: Y=0.5820+1.7348X (R2=0.678; F=35.768; P<0.0001). The equation parameters together with the correlation coefficient were as follows during activated charcoal hemoperfusion: Y=0.6827+1.2649X (R2=0.626; F=50.308; P<0.0001). Therefore, it was concluded that in patients with normal renal function, the elimination kinetics of PQ by the kidneys were only associated with the plasma PQ concentration. Activated charcoal hemoperfusion had little effect on avoiding acute kidney injury in patients with severe PQ poisoning."
] |
45 | A mutation in HNF4A leads to an increased risk of diabetes by the age of 14 years. | [
"56893404"
] | [
"Macrosomia and Hyperinsulinaemic Hypoglycaemia in Patients with Heterozygous Mutations in the HNF4A Gene. Background Macrosomia is associated with considerable neonatal and maternal morbidity. Factors that predict macrosomia are poorly understood. The increased rate of macrosomia in the offspring of pregnant women with diabetes and in congenital hyperinsulinaemia is mediated by increased foetal insulin secretion. We assessed the in utero and neonatal role of two key regulators of pancreatic insulin secretion by studying birthweight and the incidence of neonatal hypoglycaemia in patients with heterozygous mutations in the maturity-onset diabetes of the young (MODY) genes HNF4A (encoding HNF-4α) and HNF1A/TCF1 (encoding HNF-1α), and the effect of pancreatic deletion of Hnf4a on foetal and neonatal insulin secretion in mice."
] |
453 | General exercise therapy is more effective than rotator cuff exercises in reducing pain and improving function of the shoulder. | [
"4200695"
] | [
"Effect of specific exercise strategy on need for surgery in patients with subacromial impingement syndrome: randomised controlled study. OBJECTIVE To evaluate if a specific exercise strategy, targeting the rotator cuff and scapula stabilisers, improves shoulder function and pain more than unspecific exercises in patients with subacromial impingement syndrome, thereby decreasing the need for arthroscopic subacromial decompression. DESIGN Randomised, participant and single assessor blinded, controlled study. SETTING Department of orthopaedics in a Swedish university hospital. PARTICIPANTS 102 patients with long standing (over six months) persistent subacromial impingement syndrome in whom earlier conservative treatment had failed, recruited through orthopaedic specialists. INTERVENTIONS The specific exercise strategy consisted of strengthening eccentric exercises for the rotator cuff and concentric/eccentric exercises for the scapula stabilisers in combination with manual mobilisation. The control exercise programme consisted of unspecific movement exercises for the neck and shoulder. Patients in both groups received five to six individual guided treatment sessions during 12 weeks. In between these supervised sessions the participants performed home exercises once or twice a day for 12 weeks. MAIN OUTCOME MEASURES The primary outcome was the Constant-Murley shoulder assessment score evaluating shoulder function and pain. Secondary outcomes were patients' global impression of change because of treatment and decision regarding surgery. RESULTS Most (97, 95%) participants completed the 12 week study. There was a significantly greater improvement in the Constant-Murley score in the specific exercise group than in the control exercise group (24 points (95% confidence interval 19 to 28.0) v 9 points (5 to 13); mean difference between group: 15 points (8.5 to 20.6)). Significantly more patients in the specific exercise group reported successful outcome (defined as large improvement or recovered) in the patients' global assessment of change because of treatment: 69% (35/51) v 24% (11/46); odds ratio 7.6, 3.1 to 18.9; P<0.001. A significantly lower proportion of patients in the specific exercise group subsequently chose to undergo surgery: 20% (10/51) v 63% (29/46); odds ratio 7.7, 3.1 to 19.4; P<0.001). CONCLUSION A specific exercise strategy, focusing on strengthening eccentric exercises for the rotator cuff and concentric/eccentric exercises for the scapula stabilisers, is effective in reducing pain and improving shoulder function in patients with persistent subacromial impingement syndrome. By extension, this exercise strategy reduces the need for arthroscopic subacromial decompression within the three month timeframe used in the study. TRIAL REGISTRATION Clinical trials NCT01037673."
] |
454 | General exercise therapy is more effective than scapular stabilizer exercises in reducing pain and improving function of the shoulder. | [
"4200695"
] | [
"Effect of specific exercise strategy on need for surgery in patients with subacromial impingement syndrome: randomised controlled study. OBJECTIVE To evaluate if a specific exercise strategy, targeting the rotator cuff and scapula stabilisers, improves shoulder function and pain more than unspecific exercises in patients with subacromial impingement syndrome, thereby decreasing the need for arthroscopic subacromial decompression. DESIGN Randomised, participant and single assessor blinded, controlled study. SETTING Department of orthopaedics in a Swedish university hospital. PARTICIPANTS 102 patients with long standing (over six months) persistent subacromial impingement syndrome in whom earlier conservative treatment had failed, recruited through orthopaedic specialists. INTERVENTIONS The specific exercise strategy consisted of strengthening eccentric exercises for the rotator cuff and concentric/eccentric exercises for the scapula stabilisers in combination with manual mobilisation. The control exercise programme consisted of unspecific movement exercises for the neck and shoulder. Patients in both groups received five to six individual guided treatment sessions during 12 weeks. In between these supervised sessions the participants performed home exercises once or twice a day for 12 weeks. MAIN OUTCOME MEASURES The primary outcome was the Constant-Murley shoulder assessment score evaluating shoulder function and pain. Secondary outcomes were patients' global impression of change because of treatment and decision regarding surgery. RESULTS Most (97, 95%) participants completed the 12 week study. There was a significantly greater improvement in the Constant-Murley score in the specific exercise group than in the control exercise group (24 points (95% confidence interval 19 to 28.0) v 9 points (5 to 13); mean difference between group: 15 points (8.5 to 20.6)). Significantly more patients in the specific exercise group reported successful outcome (defined as large improvement or recovered) in the patients' global assessment of change because of treatment: 69% (35/51) v 24% (11/46); odds ratio 7.6, 3.1 to 18.9; P<0.001. A significantly lower proportion of patients in the specific exercise group subsequently chose to undergo surgery: 20% (10/51) v 63% (29/46); odds ratio 7.7, 3.1 to 19.4; P<0.001). CONCLUSION A specific exercise strategy, focusing on strengthening eccentric exercises for the rotator cuff and concentric/eccentric exercises for the scapula stabilisers, is effective in reducing pain and improving shoulder function in patients with persistent subacromial impingement syndrome. By extension, this exercise strategy reduces the need for arthroscopic subacromial decompression within the three month timeframe used in the study. TRIAL REGISTRATION Clinical trials NCT01037673."
] |
455 | Genes involved in pre-mRNA splicing have a significant impact on genome stability. | [
"12643937"
] | [
"A genome-wide siRNA screen reveals diverse cellular processes and pathways that mediate genome stability.. Signaling pathways that respond to DNA damage are essential for the maintenance of genome stability and are linked to many diseases, including cancer. Here, a genome-wide siRNA screen was employed to identify additional genes involved in genome stabilization by monitoring phosphorylation of the histone variant H2AX, an early mark of DNA damage. We identified hundreds of genes whose downregulation led to elevated levels of H2AX phosphorylation (gammaH2AX) and revealed links to cellular complexes and to genes with unclassified functions. We demonstrate a widespread role for mRNA-processing factors in preventing DNA damage, which in some cases is caused by aberrant RNA-DNA structures. Furthermore, we connect increased gammaH2AX levels to the neurological disorder Charcot-Marie-Tooth (CMT) syndrome, and we find a role for several CMT proteins in the DNA-damage response. These data indicate that preservation of genome stability is mediated by a larger network of biological processes than previously appreciated."
] |
456 | Genes regulated by Esrrb transcription factor are sensitive to Mbd3 function. | [
"30507607"
] | [
"An Oct4-Centered Protein Interaction Network in Embryonic Stem Cells. Transcription factors, such as Oct4, are critical for establishing and maintaining pluripotent cell identity. Whereas the genomic locations of several pluripotency transcription factors have been reported, the spectrum of their interaction partners is underexplored. Here, we use an improved affinity protocol to purify Oct4-interacting proteins from mouse embryonic stem cells (ESCs). Subsequent purification of Oct4 partners Sall4, Tcfcp2l1, Dax1, and Esrrb resulted in an Oct4 interactome of 166 proteins, including transcription factors and chromatin-modifying complexes with documented roles in self-renewal, but also many factors not previously associated with the ESC network. We find that Esrrb associated with the basal transcription machinery and also detect interactions between transcription factors and components of the TGF-beta, Notch, and Wnt signaling pathways. Acute depletion of Oct4 reduced binding of Tcfcp2l1, Dax1, and Esrrb to several target genes. In conclusion, our purification protocol allowed us to bring greater definition to the circuitry controlling pluripotent cell identity."
] |
458 | Genetic deficiency of mast cells leads to decreased weight gain in a mouse model of diet-induced obesity. | [
"597790"
] | [
"Deficiency and pharmacological stabilization of mast cells reduce diet-induced obesity and diabetes in mice. Although mast cell functions have classically been related to allergic responses, recent studies indicate that these cells contribute to other common diseases such as multiple sclerosis, rheumatoid arthritis, atherosclerosis, aortic aneurysm and cancer. This study presents evidence that mast cells also contribute to diet-induced obesity and diabetes. For example, white adipose tissue (WAT) from obese humans and mice contain more mast cells than WAT from their lean counterparts. Furthermore, in the context of mice on a Western diet, genetically induced deficiency of mast cells, or their pharmacological stabilization, reduces body weight gain and levels of inflammatory cytokines, chemokines and proteases in serum and WAT, in concert with improved glucose homeostasis and energy expenditure. Mechanistic studies reveal that mast cells contribute to WAT and muscle angiogenesis and associated cell apoptosis and cathepsin activity. Adoptive transfer experiments of cytokine-deficient mast cells show that these cells, by producing interleukin-6 (IL-6) and interferon-gamma (IFN-gamma), contribute to mouse adipose tissue cysteine protease cathepsin expression, apoptosis and angiogenesis, thereby promoting diet-induced obesity and glucose intolerance. Our results showing reduced obesity and diabetes in mice treated with clinically available mast cell-stabilizing agents suggest the potential of developing new therapies for these common human metabolic disorders."
] |
46 | A single nucleotide variant the gene DGKK is strongly associated with increased risk of hypospadias. | [
"380526"
] | [
"Common variants in DGKK are strongly associated with risk of hypospadias. Hypospadias is a common congenital malformation of the male external genitalia. We performed a genome-wide association study using pooled DNA from 436 individuals with hypospadias (cases) and 494 controls of European descent and selected the highest ranked SNPs for individual genotyping in the discovery sample, an additional Dutch sample of 133 cases and their parents, and a Swedish series of 266 cases and 402 controls. Individual genotyping of two SNPs (rs1934179 and rs7063116) in DGKK, encoding diacylglycerol kinase κ, produced compelling evidence for association with hypospadias in the discovery sample (allele-specific odds ratio (OR) = 2.5, P = 2.5 × 10−11 and OR = 2.3, P = 2.9 × 10−9, respectively) and in the Dutch (OR = 3.9, P = 2.4 × 10−5 and OR = 3.8, P = 3.4 × 10−5) and Swedish (OR = 2.5, P = 2.6 × 10−8 and OR = 2.2, P = 2.7 × 10−6) replication samples. Expression studies showed expression of DGKK in preputial tissue of cases and controls, which was lower in carriers of the risk allele of rs1934179 (P = 0.047). We propose DGKK as a major risk gene for hypospadias."
] |
461 | Genetic deletion of JAM-A increases gut permeability. | [
"40096222"
] | [
"Compromised intestinal epithelial barrier induces adaptive immune compensation that protects from colitis.. Mice lacking junctional adhesion molecule A (JAM-A, encoded by F11r) exhibit enhanced intestinal epithelial permeability, bacterial translocation, and elevated colonic lymphocyte numbers, yet do not develop colitis. To investigate the contribution of adaptive immune compensation in response to increased intestinal epithelial permeability, we examined the susceptibility of F11r(-/-)Rag1(-/-) mice to acute colitis. Although negligible contributions of adaptive immunity in F11r(+/+)Rag1(-/-) mice were observed, F11r(-/-)Rag1(-/-) mice exhibited increased microflora-dependent colitis. Elimination of T cell subsets and cytokine analyses revealed a protective role for TGF-β-producing CD4(+) T cells in F11r(-/-) mice. Additionally, loss of JAM-A resulted in elevated mucosal and serum IgA that was dependent upon CD4(+) T cells and TGF-β. Absence of IgA in F11r(+/+)Igha(-/-) mice did not affect disease, whereas F11r(-/-)Igha(-/-) mice displayed markedly increased susceptibility to acute injury-induced colitis. These data establish a role for adaptive immune-mediated protection from acute colitis under conditions of intestinal epithelial barrier compromise."
] |
463 | Genomic aberrations of metastases provide information for targeted therapy. | [
"19736671"
] | [
"Evolution of metastasis revealed by mutational landscapes of chemically induced skin cancers. Human tumors show a high level of genetic heterogeneity, but the processes that influence the timing and route of metastatic dissemination of the subclones are unknown. Here we have used whole-exome sequencing of 103 matched benign, malignant and metastatic skin tumors from genetically heterogeneous mice to demonstrate that most metastases disseminate synchronously from the primary tumor, supporting parallel rather than linear evolution as the predominant model of metastasis. Shared mutations between primary carcinomas and their matched metastases have the distinct A-to-T signature of the initiating carcinogen dimethylbenzanthracene, but non-shared mutations are primarily G-to-T, a signature associated with oxidative stress. The existence of carcinomas that either did or did not metastasize in the same host animal suggests that there are tumor-intrinsic factors that influence metastatic seeding. We also demonstrate the importance of germline polymorphisms in determining allele-specific mutations, and we identify somatic genetic alterations that are specifically related to initiation of carcinogenesis by Hras or Kras mutations. Mouse tumors that mimic the genetic heterogeneity of human cancers can aid our understanding of the clonal evolution of metastasis and provide a realistic model for the testing of novel therapies."
] |
466 | Genomic sequences involved in alternative splicing responsible for Hutchinson-Gilford progeria syndrome (HGPS) are abundant in the ''progerinonly'' allele of Lmna knock-in models. | [
"22544171"
] | [
"Reversal of the cellular phenotype in the premature aging disease Hutchinson-Gilford progeria syndrome. Hutchinson-Gilford progeria syndrome (HGPS) is a childhood premature aging disease caused by a spontaneous point mutation in lamin A (encoded by LMNA), one of the major architectural elements of the mammalian cell nucleus. The HGPS mutation activates an aberrant cryptic splice site in LMNA pre-mRNA, leading to synthesis of a truncated lamin A protein and concomitant reduction in wild-type lamin A. Fibroblasts from individuals with HGPS have severe morphological abnormalities in nuclear envelope structure. Here we show that the cellular disease phenotype is reversible in cells from individuals with HGPS. Introduction of wild-type lamin A protein does not rescue the cellular disease symptoms. The mutant LMNA mRNA and lamin A protein can be efficiently eliminated by correction of the aberrant splicing event using a modified oligonucleotide targeted to the activated cryptic splice site. Upon splicing correction, HGPS fibroblasts assume normal nuclear morphology, the aberrant nuclear distribution and cellular levels of lamina-associated proteins are rescued, defects in heterochromatin-specific histone modifications are corrected and proper expression of several misregulated genes is reestablished. Our results establish proof of principle for the correction of the premature aging phenotype in individuals with HGPS."
] |
469 | Glial calcium waves influence seizures. | [
"1410197"
] | [
"An Excitatory Loop with Astrocytes Contributes to Drive Neurons to Seizure Threshold. Seizures in focal epilepsies are sustained by a highly synchronous neuronal discharge that arises at restricted brain sites and subsequently spreads to large portions of the brain. Despite intense experimental research in this field, the earlier cellular events that initiate and sustain a focal seizure are still not well defined. Their identification is central to understand the pathophysiology of focal epilepsies and to develop new pharmacological therapies for drug-resistant forms of epilepsy. The prominent involvement of astrocytes in ictogenesis was recently proposed. We test here whether a cooperation between astrocytes and neurons is a prerequisite to support ictal (seizure-like) and interictal epileptiform events. Simultaneous patch-clamp recording and Ca2+ imaging techniques were performed in a new in vitro model of focal seizures induced by local applications of N-methyl-D-aspartic acid (NMDA) in rat entorhinal cortex slices. We found that a Ca2+ elevation in astrocytes correlates with both the initial development and the maintenance of a focal, seizure-like discharge. A delayed astrocyte activation during ictal discharges was also observed in other models (including the whole in vitro isolated guinea pig brain) in which the site of generation of seizure activity cannot be precisely monitored. In contrast, interictal discharges were not associated with Ca2+ changes in astrocytes. Selective inhibition or stimulation of astrocyte Ca2+ signalling blocked or enhanced, respectively, ictal discharges, but did not affect interictal discharge generation. Our data reveal that neurons engage astrocytes in a recurrent excitatory loop (possibly involving gliotransmission) that promotes seizure ignition and sustains the ictal discharge. This neuron-astrocyte interaction may represent a novel target to develop effective therapeutic strategies to control seizures."
] |
47 | A strong bias in the phage genome locations where the spacers were derived has been observed in many CRISPR subtypes that confer the immunity to phage. | [
"3512154",
"26996935"
] | [
"CRISPR adaptation biases explain preference for acquisition of foreign DNA. CRISPR-Cas (clustered, regularly interspaced short palindromic repeats coupled with CRISPR-associated proteins) is a bacterial immunity system that protects against invading phages or plasmids. In the process of CRISPR adaptation, short pieces of DNA ('spacers') are acquired from foreign elements and integrated into the CRISPR array. So far, it has remained a mystery how spacers are preferentially acquired from the foreign DNA while the self chromosome is avoided. Here we show that spacer acquisition is replication-dependent, and that DNA breaks formed at stalled replication forks promote spacer acquisition. Chromosomal hotspots of spacer acquisition were confined by Chi sites, which are sequence octamers highly enriched on the bacterial chromosome, suggesting that these sites limit spacer acquisition from self DNA. We further show that the avoidance of self is mediated by the RecBCD double-stranded DNA break repair complex. Our results suggest that, in Escherichia coli, acquisition of new spacers largely depends on RecBCD-mediated processing of double-stranded DNA breaks occurring primarily at replication forks, and that the preference for foreign DNA is achieved through the higher density of Chi sites on the self chromosome, in combination with the higher number of forks on the foreign DNA. This model explains the strong preference to acquire spacers both from high copy plasmids and from phages.",
"Strong bias in the bacterial CRISPR elements that confer immunity to phage.. Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas systems provide adaptive immunity against phage via spacer-encoded CRISPR RNAs that are complementary to invasive nucleic acids. Here, we challenge Streptococcus thermophilus with a bacteriophage, and used PCR-based metagenomics to monitor phage-derived spacers daily for 15 days in two experiments. Spacers that target the host chromosome are infrequent and strongly selected against, suggesting autoimmunity is lethal. In experiments that recover over half a million spacers, we observe early dominance by a few spacer sub-populations and rapid oscillations in sub-population abundances. In two CRISPR systems and in replicate experiments, a few spacers account for the majority of spacer sequences. Nearly all phage locations targeted by the acquired spacers have a proto-spacer adjacent motif (PAM), indicating PAMs are involved in spacer acquisition. We detect a strong and reproducible bias in the phage genome locations from which spacers derive. This may reflect selection for specific spacers based on location and effectiveness."
] |
470 | Glioblastoma multiforme (GBM) is characterized by extensive invasion, rapid growth, necrosis, and angiogenesis. | [
"12685434"
] | [
"Guanylate binding protein 1 is a novel effector of EGFR-driven invasion in glioblastoma. Although GBP1 (guanylate binding protein 1) was among the first interferon-inducible proteins identified, its function is still largely unknown. Epidermal growth factor receptor (EGFR) activation by amplification or mutation is one of the most frequent genetic lesions in a variety of human tumors. These include glioblastoma multiforme (GBM), which is characterized by independent but interrelated features of extensive invasion into normal brain parenchyma, rapid growth, necrosis, and angiogenesis. In this study, we show that EGFR activation promoted GBP1 expression in GBM cell lines through a signaling pathway involving Src and p38 mitogen-activated protein kinase. Moreover, we identified YY1 (Yin Yang 1) as the downstream transcriptional regulator regulating EGFR-driven GBP1 expression. GBP1 was required for EGFR-mediated MMP1 (matrix metalloproteinase 1) expression and glioma cell invasion in vitro. Although deregulation of GBP1 expression did not affect glioma cell proliferation, overexpression of GBP1 enhanced glioma cell invasion through MMP1 induction, which required its C-terminal helical domain and was independent of its GTPase activity. Reducing GBP1 levels by RNA interference in invasive GBM cells also markedly inhibited their ability to infiltrate the brain parenchyma of mice. GBP1 expression was high and positively correlated with EGFR expression in human GBM tumors and cell lines, particularly those of the neural subtype. Together, these findings establish GBP1 as a previously unknown link between EGFR activity and MMP1 expression and nominate it as a novel potential therapeutic target for inhibiting GBM invasion."
] |
472 | Glucose restriction to 0.05% reduces RLS (replicative life span) by 20-40% in S. cerevisiae. | [
"7185591",
"26330861",
"4414481"
] | [
"Sir2-Independent Life Span Extension by Calorie Restriction in Yeast. Calorie restriction slows aging and increases life span in many organisms. In yeast, a mechanistic explanation has been proposed whereby calorie restriction slows aging by activating Sir2. Here we report the identification of a Sir2-independent pathway responsible for a majority of the longevity benefit associated with calorie restriction. Deletion of FOB1 and overexpression of SIR2 have been previously found to increase life span by reducing the levels of toxic rDNA circles in aged mother cells. We find that combining calorie restriction with either of these genetic interventions dramatically enhances longevity, resulting in the longest-lived yeast strain reported thus far. Further, calorie restriction results in a greater life span extension in cells lacking both Sir2 and Fob1 than in cells where Sir2 is present. These findings indicate that Sir2 and calorie restriction act in parallel pathways to promote longevity in yeast and, perhaps, higher eukaryotes.",
"Requirement of NAD and SIR2 for life-span extension by calorie restriction in Saccharomyces cerevisiae.. Calorie restriction extends life-span in a wide variety of organisms. Although it has been suggested that calorie restriction may work by reducing the levels of reactive oxygen species produced during respiration, the mechanism by which this regimen slows aging is uncertain. Here, we mimicked calorie restriction in yeast by physiological or genetic means and showed a substantial extension in life-span. This extension was not observed in strains mutant for SIR2 (which encodes the silencing protein Sir2p) or NPT1 (a gene in a pathway in the synthesis of NAD, the oxidized form of nicotinamide adenine dinucleotide). These findings suggest that the increased longevity induced by calorie restriction requires the activation of Sir2p by NAD.",
"Calorie restriction extends Saccharomyces cerevisiae lifespan by increasing respiration. Calorie restriction (CR) extends lifespan in a wide spectrum of organisms and is the only regimen known to lengthen the lifespan of mammals. We established a model of CR in budding yeast Saccharomyces cerevisiae. In this system, lifespan can be extended by limiting glucose or by reducing the activity of the glucose-sensing cyclic-AMP-dependent kinase (PKA). Lifespan extension in a mutant with reduced PKA activity requires Sir2 and NAD (nicotinamide adenine dinucleotide). In this study we explore how CR activates Sir2 to extend lifespan. Here we show that the shunting of carbon metabolism toward the mitochondrial tricarboxylic acid cycle and the concomitant increase in respiration play a central part in this process. We discuss how this metabolic strategy may apply to CR in animals."
] |
473 | Glycan adaptation involves insertion-deletion events. | [
"4373433"
] | [
"Broad neutralization coverage of HIV by multiple highly potent antibodies. Broadly neutralizing antibodies against highly variable viral pathogens are much sought after to treat or protect against global circulating viruses. Here we probed the neutralizing antibody repertoires of four human immunodeficiency virus (HIV)-infected donors with remarkably broad and potent neutralizing responses and rescued 17 new monoclonal antibodies that neutralize broadly across clades. Many of the new monoclonal antibodies are almost tenfold more potent than the recently described PG9, PG16 and VRC01 broadly neutralizing monoclonal antibodies and 100-fold more potent than the original prototype HIV broadly neutralizing monoclonal antibodies. The monoclonal antibodies largely recapitulate the neutralization breadth found in the corresponding donor serum and many recognize novel epitopes on envelope (Env) glycoprotein gp120, illuminating new targets for vaccine design. Analysis of neutralization by the full complement of anti-HIV broadly neutralizing monoclonal antibodies now available reveals that certain combinations of antibodies should offer markedly more favourable coverage of the enormous diversity of global circulating viruses than others and these combinations might be sought in active or passive immunization regimes. Overall, the isolation of multiple HIV broadly neutralizing monoclonal antibodies from several donors that, in aggregate, provide broad coverage at low concentrations is a highly positive indicator for the eventual design of an effective antibody-based HIV vaccine."
] |
474 | Glycan adaptation is rarely observed in the B-cell repertoire. | [
"4373433"
] | [
"Broad neutralization coverage of HIV by multiple highly potent antibodies. Broadly neutralizing antibodies against highly variable viral pathogens are much sought after to treat or protect against global circulating viruses. Here we probed the neutralizing antibody repertoires of four human immunodeficiency virus (HIV)-infected donors with remarkably broad and potent neutralizing responses and rescued 17 new monoclonal antibodies that neutralize broadly across clades. Many of the new monoclonal antibodies are almost tenfold more potent than the recently described PG9, PG16 and VRC01 broadly neutralizing monoclonal antibodies and 100-fold more potent than the original prototype HIV broadly neutralizing monoclonal antibodies. The monoclonal antibodies largely recapitulate the neutralization breadth found in the corresponding donor serum and many recognize novel epitopes on envelope (Env) glycoprotein gp120, illuminating new targets for vaccine design. Analysis of neutralization by the full complement of anti-HIV broadly neutralizing monoclonal antibodies now available reveals that certain combinations of antibodies should offer markedly more favourable coverage of the enormous diversity of global circulating viruses than others and these combinations might be sought in active or passive immunization regimes. Overall, the isolation of multiple HIV broadly neutralizing monoclonal antibodies from several donors that, in aggregate, provide broad coverage at low concentrations is a highly positive indicator for the eventual design of an effective antibody-based HIV vaccine."
] |
479 | Gpr124 increases BBB breakdown in mouse models of ischemic stroke. | [
"6325527"
] | [
"Gpr124 is essential for blood–brain barrier integrity in central nervous system disease. Although blood–brain barrier (BBB) compromise is central to the etiology of diverse central nervous system (CNS) disorders, endothelial receptor proteins that control BBB function are poorly defined. The endothelial G-protein-coupled receptor (GPCR) Gpr124 has been reported to be required for normal forebrain angiogenesis and BBB function in mouse embryos, but the role of this receptor in adult animals is unknown. Here Gpr124 conditional knockout (CKO) in the endothelia of adult mice did not affect homeostatic BBB integrity, but resulted in BBB disruption and microvascular hemorrhage in mouse models of both ischemic stroke and glioblastoma, accompanied by reduced cerebrovascular canonical Wnt–β-catenin signaling. Constitutive activation of Wnt–β-catenin signaling fully corrected the BBB disruption and hemorrhage defects of Gpr124-CKO mice, with rescue of the endothelial gene tight junction, pericyte coverage and extracellular-matrix deficits. We thus identify Gpr124 as an endothelial GPCR specifically required for endothelial Wnt signaling and BBB integrity under pathological conditions in adult mice. This finding implicates Gpr124 as a potential therapeutic target for human CNS disorders characterized by BBB disruption."
] |
480 | Gpr124 suppresses BBB breakdown in mouse models of ischemic stroke. | [
"6325527"
] | [
"Gpr124 is essential for blood–brain barrier integrity in central nervous system disease. Although blood–brain barrier (BBB) compromise is central to the etiology of diverse central nervous system (CNS) disorders, endothelial receptor proteins that control BBB function are poorly defined. The endothelial G-protein-coupled receptor (GPCR) Gpr124 has been reported to be required for normal forebrain angiogenesis and BBB function in mouse embryos, but the role of this receptor in adult animals is unknown. Here Gpr124 conditional knockout (CKO) in the endothelia of adult mice did not affect homeostatic BBB integrity, but resulted in BBB disruption and microvascular hemorrhage in mouse models of both ischemic stroke and glioblastoma, accompanied by reduced cerebrovascular canonical Wnt–β-catenin signaling. Constitutive activation of Wnt–β-catenin signaling fully corrected the BBB disruption and hemorrhage defects of Gpr124-CKO mice, with rescue of the endothelial gene tight junction, pericyte coverage and extracellular-matrix deficits. We thus identify Gpr124 as an endothelial GPCR specifically required for endothelial Wnt signaling and BBB integrity under pathological conditions in adult mice. This finding implicates Gpr124 as a potential therapeutic target for human CNS disorders characterized by BBB disruption."
] |
481 | Guanine nucleotide dissociation inhibitor (Rho-GDI) interacts with the p75 NTR death domain | [
"14706752"
] | [
"Gamma-Secretase Represents a Therapeutic Target for the Treatment of Invasive Glioma Mediated by the p75 Neurotrophin Receptor. The multifunctional signaling protein p75 neurotrophin receptor (p75(NTR)) is a central regulator and major contributor to the highly invasive nature of malignant gliomas. Here, we show that neurotrophin-dependent regulated intramembrane proteolysis (RIP) of p75(NTR) is required for p75(NTR)-mediated glioma invasion, and identify a previously unnamed process for targeted glioma therapy. Expression of cleavage-resistant chimeras of p75(NTR) or treatment of animals bearing p75(NTR)-positive intracranial tumors with clinically applicable gamma-secretase inhibitors resulted in dramatically decreased glioma invasion and prolonged survival. Importantly, proteolytic processing of p75(NTR) was observed in p75(NTR)-positive patient tumor specimens and brain tumor initiating cells. This work highlights the importance of p75(NTR) as a therapeutic target, suggesting that gamma-secretase inhibitors may have direct clinical application for the treatment of malignant glioma."
] |
482 | Guanine nucleotide exchange factors (GEFs) mediate RhoA activation in response to tensional forces on fibronectin-binding integrins. | [
"10991183"
] | [
"The Rho GEFs LARG and GEF-H1 regulate the mechanical response to force on integrins. How individual cells respond to mechanical forces is of considerable interest to biologists as force affects many aspects of cell behaviour. The application of force on integrins triggers cytoskeletal rearrangements and growth of the associated adhesion complex, resulting in increased cellular stiffness, also known as reinforcement. Although RhoA has been shown to play a role during reinforcement, the molecular mechanisms that regulate its activity are unknown. By combining biochemical and biophysical approaches, we identified two guanine nucleotide exchange factors (GEFs), LARG and GEF-H1, as key molecules that regulate the cellular adaptation to force. We show that stimulation of integrins with tensional force triggers activation of these two GEFs and their recruitment to adhesion complexes. Surprisingly, activation of LARG and GEF-H1 involves distinct signalling pathways. Our results reveal that LARG is activated by the Src family tyrosine kinase Fyn, whereas GEF-H1 catalytic activity is enhanced by ERK downstream of a signalling cascade that includes FAK and Ras."
] |
483 | H.pylori-mediated gastric cancer occurs due to the accumulation of mutations in host epithelial cells. | [
"22703082"
] | [
"Helicobacter pylori infection triggers aberrant expression of activation-induced cytidine deaminase in gastric epithelium. Infection with Helicobacter pylori (H. pylori) is a risk factor for the development of gastric cancer. Here we show that infection of gastric epithelial cells with 'cag' pathogenicity island (cagPAI)-positive H. pylori induced aberrant expression of activation-induced cytidine deaminase (AID), a member of the cytidine-deaminase family that acts as a DNA- and RNA-editing enzyme, via the IκB kinase–dependent nuclear factor-κB activation pathway. H. pylori–mediated upregulation of AID resulted in the accumulation of nucleotide alterations in the TP53 tumor suppressor gene in gastric cells in vitro. Our findings provide evidence that aberrant AID expression caused by H. pylori infection might be a mechanism of mutation accumulation in the gastric mucosa during H. pylori–associated gastric carcinogenesis."
] |
484 | H4 G94P proteins induce chromatin assembly, which increases free histones. | [
"14637235"
] | [
"Histone levels are regulated by phosphorylation and ubiquitylation dependent proteolysis. Histone levels are tightly regulated to prevent harmful effects such as genomic instability and hypersensitivity to DNA-damaging agents due to the accumulation of these highly basic proteins when DNA replication slows down or stops. Although chromosomal histones are stable, excess (non-chromatin bound) histones are rapidly degraded in a Rad53 (radiation sensitive 53) kinase-dependent manner in Saccharomyces cerevisiae. Here we demonstrate that excess histones associate with Rad53 in vivo and seem to undergo modifications such as tyrosine phosphorylation and polyubiquitylation, before their proteolysis by the proteasome. We have identified the Tyr 99 residue of histone H3 as being critical for the efficient ubiquitylation and degradation of this histone. We have also identified the ubiquitin conjugating enzymes (E2) Ubc4 and Ubc5, as well as the ubiquitin ligase (E3) Tom1 (temperature dependent organization in mitotic nucleus 1), as enzymes involved in the ubiquitylation of excess histones. Regulated histone proteolysis has major implications for the maintenance of epigenetic marks on chromatin, genomic stability and the packaging of sperm DNA."
] |
485 | H4 G94P proteins induce degradation of free histones via Rad53-dependent mechanisms. | [
"14637235"
] | [
"Histone levels are regulated by phosphorylation and ubiquitylation dependent proteolysis. Histone levels are tightly regulated to prevent harmful effects such as genomic instability and hypersensitivity to DNA-damaging agents due to the accumulation of these highly basic proteins when DNA replication slows down or stops. Although chromosomal histones are stable, excess (non-chromatin bound) histones are rapidly degraded in a Rad53 (radiation sensitive 53) kinase-dependent manner in Saccharomyces cerevisiae. Here we demonstrate that excess histones associate with Rad53 in vivo and seem to undergo modifications such as tyrosine phosphorylation and polyubiquitylation, before their proteolysis by the proteasome. We have identified the Tyr 99 residue of histone H3 as being critical for the efficient ubiquitylation and degradation of this histone. We have also identified the ubiquitin conjugating enzymes (E2) Ubc4 and Ubc5, as well as the ubiquitin ligase (E3) Tom1 (temperature dependent organization in mitotic nucleus 1), as enzymes involved in the ubiquitylation of excess histones. Regulated histone proteolysis has major implications for the maintenance of epigenetic marks on chromatin, genomic stability and the packaging of sperm DNA."
] |
486 | H4 G94P proteins inhibit chromatin assembly, which decreases free histones. | [
"14637235"
] | [
"Histone levels are regulated by phosphorylation and ubiquitylation dependent proteolysis. Histone levels are tightly regulated to prevent harmful effects such as genomic instability and hypersensitivity to DNA-damaging agents due to the accumulation of these highly basic proteins when DNA replication slows down or stops. Although chromosomal histones are stable, excess (non-chromatin bound) histones are rapidly degraded in a Rad53 (radiation sensitive 53) kinase-dependent manner in Saccharomyces cerevisiae. Here we demonstrate that excess histones associate with Rad53 in vivo and seem to undergo modifications such as tyrosine phosphorylation and polyubiquitylation, before their proteolysis by the proteasome. We have identified the Tyr 99 residue of histone H3 as being critical for the efficient ubiquitylation and degradation of this histone. We have also identified the ubiquitin conjugating enzymes (E2) Ubc4 and Ubc5, as well as the ubiquitin ligase (E3) Tom1 (temperature dependent organization in mitotic nucleus 1), as enzymes involved in the ubiquitylation of excess histones. Regulated histone proteolysis has major implications for the maintenance of epigenetic marks on chromatin, genomic stability and the packaging of sperm DNA."
] |
487 | H4 G94P proteins suppress degradation of free histones via Rad53-dependent mechanisms. | [
"14637235"
] | [
"Histone levels are regulated by phosphorylation and ubiquitylation dependent proteolysis. Histone levels are tightly regulated to prevent harmful effects such as genomic instability and hypersensitivity to DNA-damaging agents due to the accumulation of these highly basic proteins when DNA replication slows down or stops. Although chromosomal histones are stable, excess (non-chromatin bound) histones are rapidly degraded in a Rad53 (radiation sensitive 53) kinase-dependent manner in Saccharomyces cerevisiae. Here we demonstrate that excess histones associate with Rad53 in vivo and seem to undergo modifications such as tyrosine phosphorylation and polyubiquitylation, before their proteolysis by the proteasome. We have identified the Tyr 99 residue of histone H3 as being critical for the efficient ubiquitylation and degradation of this histone. We have also identified the ubiquitin conjugating enzymes (E2) Ubc4 and Ubc5, as well as the ubiquitin ligase (E3) Tom1 (temperature dependent organization in mitotic nucleus 1), as enzymes involved in the ubiquitylation of excess histones. Regulated histone proteolysis has major implications for the maintenance of epigenetic marks on chromatin, genomic stability and the packaging of sperm DNA."
] |
488 | HAND2 methylation is a key step in early endometrial carcinogenesis. | [
"1780819"
] | [
"Role of DNA Methylation and Epigenetic Silencing of HAND2 in Endometrial Cancer Development. BACKGROUND Endometrial cancer incidence is continuing to rise in the wake of the current ageing and obesity epidemics. Much of the risk for endometrial cancer development is influenced by the environment and lifestyle. Accumulating evidence suggests that the epigenome serves as the interface between the genome and the environment and that hypermethylation of stem cell polycomb group target genes is an epigenetic hallmark of cancer. The objective of this study was to determine the functional role of epigenetic factors in endometrial cancer development. METHODS AND FINDINGS Epigenome-wide methylation analysis of >27,000 CpG sites in endometrial cancer tissue samples (n = 64) and control samples (n = 23) revealed that HAND2 (a gene encoding a transcription factor expressed in the endometrial stroma) is one of the most commonly hypermethylated and silenced genes in endometrial cancer. A novel integrative epigenome-transcriptome-interactome analysis further revealed that HAND2 is the hub of the most highly ranked differential methylation hotspot in endometrial cancer. These findings were validated using candidate gene methylation analysis in multiple clinical sample sets of tissue samples from a total of 272 additional women. Increased HAND2 methylation was a feature of premalignant endometrial lesions and was seen to parallel a decrease in RNA and protein levels. Furthermore, women with high endometrial HAND2 methylation in their premalignant lesions were less likely to respond to progesterone treatment. HAND2 methylation analysis of endometrial secretions collected using high vaginal swabs taken from women with postmenopausal bleeding specifically identified those patients with early stage endometrial cancer with both high sensitivity and high specificity (receiver operating characteristics area under the curve = 0.91 for stage 1A and 0.97 for higher than stage 1A). Finally, mice harbouring a Hand2 knock-out specifically in their endometrium were shown to develop precancerous endometrial lesions with increasing age, and these lesions also demonstrated a lack of PTEN expression. CONCLUSIONS HAND2 methylation is a common and crucial molecular alteration in endometrial cancer that could potentially be employed as a biomarker for early detection of endometrial cancer and as a predictor of treatment response. The true clinical utility of HAND2 DNA methylation, however, requires further validation in prospective studies. Please see later in the article for the Editors' Summary."
] |
489 | HIV trans-activator protein (TAT) effectively transports large and small molecules across cellular membranes into larger populations of neurons. | [
"6625693"
] | [
"Suppression of inflammatory and neuropathic pain by uncoupling CRMP-2 from the presynaptic Ca2+ channel complex. The use of N-type voltage-gated calcium channel (CaV2.2) blockers to treat pain is limited by many physiological side effects. Here we report that inflammatory and neuropathic hypersensitivity can be suppressed by inhibiting the binding of collapsin response mediator protein 2 (CRMP-2) to CaV2.2 and thereby reducing channel function. A peptide of CRMP-2 fused to the HIV transactivator of transcription (TAT) protein (TAT-CBD3) decreased neuropeptide release from sensory neurons and excitatory synaptic transmission in dorsal horn neurons, reduced meningeal blood flow, reduced nocifensive behavior induced by formalin injection or corneal capsaicin application and reversed neuropathic hypersensitivity produced by an antiretroviral drug. TAT-CBD3 was mildly anxiolytic without affecting memory retrieval, sensorimotor function or depression. At doses tenfold higher than that required to reduce hypersensitivity in vivo, TAT-CBD3 caused a transient episode of tail kinking and body contortion. By preventing CRMP-2–mediated enhancement of CaV2.2 function, TAT-CBD3 alleviated inflammatory and neuropathic hypersensitivity, an approach that may prove useful in managing chronic pain."
] |
490 | HNF4A mutations are associated with macrosomia in infancy. | [
"56893404"
] | [
"Macrosomia and Hyperinsulinaemic Hypoglycaemia in Patients with Heterozygous Mutations in the HNF4A Gene. Background Macrosomia is associated with considerable neonatal and maternal morbidity. Factors that predict macrosomia are poorly understood. The increased rate of macrosomia in the offspring of pregnant women with diabetes and in congenital hyperinsulinaemia is mediated by increased foetal insulin secretion. We assessed the in utero and neonatal role of two key regulators of pancreatic insulin secretion by studying birthweight and the incidence of neonatal hypoglycaemia in patients with heterozygous mutations in the maturity-onset diabetes of the young (MODY) genes HNF4A (encoding HNF-4α) and HNF1A/TCF1 (encoding HNF-1α), and the effect of pancreatic deletion of Hnf4a on foetal and neonatal insulin secretion in mice."
] |
492 | HOXB4 facilitates HSC expansion when co-cultured with HSCs. | [
"19583924"
] | [
"Angiopoietin-like proteins stimulate ex vivo expansion of hematopoietic stem cells. Successful ex vivo expansion of hematopoietic stem cells (HSCs) would greatly benefit the treatment of disease and the understanding of crucial questions of stem cell biology. Here we show, using microarray studies, that the HSC-supportive mouse fetal liver CD3+ cells specifically express the proteins angiopoietin-like 2 (Angptl2) and angiopoietin-like 3 (Angptl3). We observed a 24- or 30-fold net expansion of long-term HSCs by reconstitution analysis when we cultured highly enriched HSCs for 10 days in the presence of Angptl2 or Angptl3 together with saturating levels of other growth factors. The coiled-coil domain of Angptl2 was capable of stimulating expansion of HSCs. Furthermore, angiopoietin-like 5, angiopoietin-like 7 and microfibril-associated glycoprotein 4 also supported expansion of HSCs in culture."
] |
493 | HOXB4 is a highly expressed component of cellular secretome from fetal liver cell populations. | [
"19583924"
] | [
"Angiopoietin-like proteins stimulate ex vivo expansion of hematopoietic stem cells. Successful ex vivo expansion of hematopoietic stem cells (HSCs) would greatly benefit the treatment of disease and the understanding of crucial questions of stem cell biology. Here we show, using microarray studies, that the HSC-supportive mouse fetal liver CD3+ cells specifically express the proteins angiopoietin-like 2 (Angptl2) and angiopoietin-like 3 (Angptl3). We observed a 24- or 30-fold net expansion of long-term HSCs by reconstitution analysis when we cultured highly enriched HSCs for 10 days in the presence of Angptl2 or Angptl3 together with saturating levels of other growth factors. The coiled-coil domain of Angptl2 was capable of stimulating expansion of HSCs. Furthermore, angiopoietin-like 5, angiopoietin-like 7 and microfibril-associated glycoprotein 4 also supported expansion of HSCs in culture."
] |
494 | HSCT-T dosage may not be diagnostic if the onset of symptoms occurs less than 3 hours before AMI. | [
"34873974"
] | [
"Diagnostic accuracy of single baseline measurement of Elecsys Troponin T high-sensitive assay for diagnosis of acute myocardial infarction in emergency department: systematic review and meta-analysis. OBJECTIVE To obtain summary estimates of the accuracy of a single baseline measurement of the Elecsys Troponin T high-sensitive assay (Roche Diagnostics) for the diagnosis of acute myocardial infarction in patients presenting to the emergency department. DESIGN Systematic review and meta-analysis of diagnostic test accuracy studies. DATA SOURCES Medline, Embase, and other relevant electronic databases were searched for papers published between January 2006 and December 2013. STUDY SELECTION Studies were included if they evaluated the diagnostic accuracy of a single baseline measurement of Elecsys Troponin T high-sensitive assay for the diagnosis of acute myocardial infarction in patients presenting to the emergency department with suspected acute coronary syndrome. STUDY APPRAISAL AND DATA SYNTHESIS The first author screened all titles and abstracts identified through the searches and selected all potentially relevant papers. The screening of the full texts, the data extraction, and the methodological quality assessment, using the adapted QUADAS-2 tool, were conducted independently by two reviewers with disagreements being resolved through discussion or arbitration. If appropriate, meta-analysis was conducted using the hierarchical bivariate model. RESULTS Twenty three studies reported the performance of the evaluated assay at presentation. The results for 14 ng/L and 3-5 ng/L cut-off values were pooled separately. At 14 ng/L (20 papers), the summary sensitivity was 89.5% (95% confidence interval 86.3% to 92.1%) and the summary specificity was 77.1% (68.7% to 83.7%). At 3-5 ng/L (six papers), the summary sensitivity was 97.4% (94.9% to 98.7%) and the summary specificity was 42.4% (31.2% to 54.5%). This means that if 21 of 100 consecutive patients have the target condition (21%, the median prevalence across the studies), 2 (95% confidence interval 2 to 3) of 21 patients with acute myocardial infarction will be missed (false negatives) if 14 ng/L is used as a cut-off value and 18 (13 to 25) of 79 patients without acute myocardial infarction will test positive (false positives). If the 3-5 ng/L cut-off value is used, <1 (0 to 1) patient with acute myocardial infarction will be missed and 46 (36 to 54) patients without acute myocardial infarction will test positive. CONCLUSIONS The results indicate that a single baseline measurement of the Elecsys Troponin T high-sensitive assay could be used to rule out acute myocardial infarction if lower cut-off values such as 3 ng/L or 5 ng/L are used. However, this method should be part of a comprehensive triage strategy and may not be appropriate for patients who present less than three hours after symptom onset. Care must also be exercised because of the higher imprecision of the evaluated assay and the greater effect of lot-to-lot reagent variation at low troponin concentrations. SYSTEMATIC REVIEW REGISTRATION PROSPERO registration number CRD42013003926."
] |
495 | Having a main partner improves HIV outcomes. | [
"17077004"
] | [
"Stable partnership and progression to AIDS or death in HIV infected patients receiving highly active antiretroviral therapy: Swiss HIV cohort study.. OBJECTIVES To explore the association between a stable partnership and clinical outcome in HIV infected patients receiving highly active antiretroviral therapy (HAART). DESIGN Prospective cohort study of adults with HIV (Swiss HIV cohort study). SETTING Seven outpatient clinics throughout Switzerland. PARTICIPANTS The 3736 patients in the cohort who started HAART before 2002 (median age 36 years, 29% female, median follow up 3.6 years). MAIN OUTCOME MEASURES Time to AIDS or death (primary endpoint), death alone, increases in CD4 cell count of at least 50 and 100 above baseline, optimal viral suppression (a viral load below 400 copies/ml), and viral rebound. RESULTS During follow up 2985 (80%) participants reported a stable partnership on at least one occasion. When starting HAART, 52% (545/1042) of participants reported a stable partnership; after five years of follow up 46% (190/412) of participants reported a stable partnership. In an analysis stratified by previous antiretroviral therapy and clinical stage when starting HAART (US Centers for Disease Control and Prevention group A, B, or C), the adjusted hazard ratio for progression to AIDS or death was 0.79 (95% confidence interval 0.63 to 0.98) for participants with a stable partnership compared with those without. Adjusted hazards ratios for other endpoints were 0.59 (0.44 to 0.79) for progression to death, 1.15 (1.06 to 1.24) for an increase in CD4 cells of 100 counts/microl or more, and 1.06 (0.98 to 1.14) for optimal viral suppression. CONCLUSIONS A stable partnership is associated with a slower rate of progression to AIDS or death in HIV infected patients receiving HAART."
] |
498 | Having a main partner worsens HIV outcomes. | [
"17077004"
] | [
"Stable partnership and progression to AIDS or death in HIV infected patients receiving highly active antiretroviral therapy: Swiss HIV cohort study.. OBJECTIVES To explore the association between a stable partnership and clinical outcome in HIV infected patients receiving highly active antiretroviral therapy (HAART). DESIGN Prospective cohort study of adults with HIV (Swiss HIV cohort study). SETTING Seven outpatient clinics throughout Switzerland. PARTICIPANTS The 3736 patients in the cohort who started HAART before 2002 (median age 36 years, 29% female, median follow up 3.6 years). MAIN OUTCOME MEASURES Time to AIDS or death (primary endpoint), death alone, increases in CD4 cell count of at least 50 and 100 above baseline, optimal viral suppression (a viral load below 400 copies/ml), and viral rebound. RESULTS During follow up 2985 (80%) participants reported a stable partnership on at least one occasion. When starting HAART, 52% (545/1042) of participants reported a stable partnership; after five years of follow up 46% (190/412) of participants reported a stable partnership. In an analysis stratified by previous antiretroviral therapy and clinical stage when starting HAART (US Centers for Disease Control and Prevention group A, B, or C), the adjusted hazard ratio for progression to AIDS or death was 0.79 (95% confidence interval 0.63 to 0.98) for participants with a stable partnership compared with those without. Adjusted hazards ratios for other endpoints were 0.59 (0.44 to 0.79) for progression to death, 1.15 (1.06 to 1.24) for an increase in CD4 cells of 100 counts/microl or more, and 1.06 (0.98 to 1.14) for optimal viral suppression. CONCLUSIONS A stable partnership is associated with a slower rate of progression to AIDS or death in HIV infected patients receiving HAART."
] |
499 | HbA1c consistently overestimates glycemic control in black individuals with Sickle cell trait (SCT). | [
"26064662"
] | [
"Association of Sickle Cell Trait With Hemoglobin A1c in African Americans. Importance Hemoglobin A1c (HbA1c) reflects past glucose concentrations, but this relationship may differ between those with sickle cell trait (SCT) and those without it. Objective To evaluate the association between SCT and HbA1c for given levels of fasting or 2-hour glucose levels among African Americans. Design, Setting, and Participants Retrospective cohort study using data collected from 7938 participants in 2 community-based cohorts, the Coronary Artery Risk Development in Young Adults (CARDIA) study and the Jackson Heart Study (JHS). From the CARDIA study, 2637 patients contributed a maximum of 2 visits (2005-2011); from the JHS, 5301 participants contributed a maximum of 3 visits (2000-2013). All visits were scheduled at approximately 5-year intervals. Participants without SCT data, those without any concurrent HbA1c and glucose measurements, and those with hemoglobin variants HbSS, HbCC, or HbAC were excluded. Analysis of the primary outcome was conducted using generalized estimating equations (GEE) to examine the association of SCT with HbA1c levels, controlling for fasting or 2-hour glucose measures. Exposures Presence of SCT. Main Outcomes and Measures Hemoglobin A1c stratified by the presence or absence of SCT was the primary outcome measure. Results The analytic sample included 4620 participants (mean age, 52.3 [SD, 11.8] years; 2835 women [61.3%]; 367 [7.9%] with SCT) with 9062 concurrent measures of fasting glucose and HbA1c levels. In unadjusted GEE analyses, for a given fasting glucose, HbA1c values were statistically significantly lower in those with (5.72%) vs those without (6.01%) SCT (mean HbA1c difference, −0.29%; 95% CI, −0.35% to −0.23%). Findings were similar in models adjusted for key risk factors and in analyses using 2001 concurrent measures of 2-hour glucose and HbA1c concentration for those with SCT (mean, 5.35%) vs those without SCT (mean, 5.65%) for a mean HbA1c difference of −0.30% (95% CI, −0.39% to −0.21%). The HbA1c difference by SCT was greater at higher fasting (P = .02 for interaction) and 2-hour (P = .03) glucose concentrations. The prevalence of prediabetes and diabetes was statistically significantly lower among participants with SCT when defined using HbA1c values (29.2% vs 48.6% for prediabetes and 3.8% vs 7.3% for diabetes in 572 observations from participants with SCT and 6877 observations from participants without SCT; P<.001 for both comparisons). Conclusions and Relevance Among African Americans from 2 large, well-established cohorts, participants with SCT had lower levels of HbA1c at any given concentration of fasting or 2-hour glucose compared with participants without SCT. These findings suggest that HbA1c may systematically underestimate past glycemia in black patients with SCT and may require further evaluation."
] |
500 | Headaches are correlated with cognitive impairment. | [
"17930286"
] | [
"Headache, migraine, and structural brain lesions and function: population based Epidemiology of Vascular Ageing-MRI study. OBJECTIVE To evaluate the association of overall and specific headaches with volume of white matter hyperintensities, brain infarcts, and cognition. DESIGN Population based, cross sectional study. SETTING Epidemiology of Vascular Ageing study, Nantes, France. PARTICIPANTS 780 participants (mean age 69, 58.5% women) with detailed headache assessment. MAIN OUTCOME MEASURES Brain scans were evaluated for volume of white matter hyperintensities (by fully automated imaging processing) and for classification of infarcts (by visual reading with a standardised assessment grid). Cognitive function was assessed by a battery of tests including the mini-mental state examination. RESULTS 163 (20.9%) participants reported a history of severe headache and 116 had migraine, of whom 17 (14.7%) reported aura symptoms. An association was found between any history of severe headache and increasing volume of white matter hyperintensities. The adjusted odds ratio of being in the highest third for total volume of white matter hyperintensities was 2.0 (95% confidence interval 1.3 to 3.1, P for trend 0.002) for participants with any history of severe headache when compared with participants without severe headache being in the lowest third. The association pattern was similar for all headache types. Migraine with aura was the only headache type strongly associated with volume of deep white matter hyperintensities (highest third odds ratio 12.4, 1.6 to 99.4, P for trend 0.005) and with brain infarcts (3.4, 1.2 to 9.3). The location of infarcts was predominantly outside the cerebellum and brain stem. Evidence was lacking for cognitive impairment for any headache type with or without brain lesions. CONCLUSIONS In this population based study, any history of severe headache was associated with an increased volume of white matter hyperintensities. Migraine with aura was the only headache type associated with brain infarcts. Evidence that headache of any type by itself or in combination with brain lesions was associated with cognitive impairment was lacking."
] |
504 | Healthy volunteers exhibit rapid and transient increase of cellular ATP after being bolus-injected with fructose. | [
"10883736"
] | [
"Alterations in liver ATP homeostasis in human nonalcoholic steatohepatitis: a pilot study.. CONTEXT The mechanisms that drive progression from fatty liver to steatohepatitis and cirrhosis are unknown. In animal models, obese mice with fatty livers are vulnerable to liver adenosine triphosphate (ATP) depletion and necrosis, suggesting that altered hepatic energy homeostasis may be involved. OBJECTIVE To determine if patients with fatty liver disease exhibit impaired recovery from hepatic ATP depletion. DESIGN Laboratory analysis of liver ATP stores monitored by nuclear magnetic resonance spectroscopy before and after transient hepatic ATP depletion was induced by fructose injection. The study was conducted between July 15 and August 30, 1998. SETTING University hospital. PATIENTS Eight consecutive adults with biopsy-proven nonalcoholic steatohepatitis and 7 healthy age- and sex-matched controls. MAIN OUTCOME MEASURE Level of ATP 1 hour after fructose infusion in patients vs controls. RESULTS In patients, serum aminotransferase levels were increased (P = .02 vs controls); albumin and bilirubin values were normal and clinical evidence of portal hypertension was absent in both groups. However, 2 patients had moderate fibrosis and 1 had cirrhosis on liver biopsy. Mean serum glucose, cholesterol, and triglyceride levels were similar between groups but patients weighed significantly more than controls (P = .02). Liver ATP levels were similar in the 2 groups before fructose infusion and decreased similarly in both after fructose infusion (P = .01 vs initial ATP levels). However, controls replenished their hepatic ATP stores during the 1-hour follow-up period (P<.02 vs minimum ATP) but patients did not. Hence, patients' hepatic ATP levels were lower than those of controls at the end of the study (P = .04). Body mass index (BMI) correlated inversely with ATP recovery, even in controls (R = -0.768; P = .07). Although BMI was greater in patients than controls (P = .02) and correlated strongly with fatty liver and serum aminotransferase elevations, neither of the latter 2 parameters nor the histologic severity of fibrosis strongly predicted hepatic ATP recovery. CONCLUSIONS These data suggest that recovery from hepatic ATP depletion becomes progressively less efficient as body mass increases in healthy controls and is severely impaired in patients with obesity-related nonalcoholic steatohepatitis."
] |
505 | Helicobacter pylori-induced aberrant NF-kB-dependent expression of activation-induced cytidine deaminase contributes to the mutagenesis of host DNA. | [
"22703082"
] | [
"Helicobacter pylori infection triggers aberrant expression of activation-induced cytidine deaminase in gastric epithelium. Infection with Helicobacter pylori (H. pylori) is a risk factor for the development of gastric cancer. Here we show that infection of gastric epithelial cells with 'cag' pathogenicity island (cagPAI)-positive H. pylori induced aberrant expression of activation-induced cytidine deaminase (AID), a member of the cytidine-deaminase family that acts as a DNA- and RNA-editing enzyme, via the IκB kinase–dependent nuclear factor-κB activation pathway. H. pylori–mediated upregulation of AID resulted in the accumulation of nucleotide alterations in the TP53 tumor suppressor gene in gastric cells in vitro. Our findings provide evidence that aberrant AID expression caused by H. pylori infection might be a mechanism of mutation accumulation in the gastric mucosa during H. pylori–associated gastric carcinogenesis."
] |
506 | Helminths interfere with immune system control of coinfections by microbial pathogens 16. | [
"7433668"
] | [
"Preexisting helminth infection induces inhibition of innate pulmonary anti-tuberculosis defense by engaging the IL-4 receptor pathway. Tuberculosis and helminthic infections coexist in many parts of the world, yet the impact of helminth-elicited Th2 responses on the ability of the host to control Mycobacterium tuberculosis (Mtb) infection has not been fully explored. We show that mice infected with the intestinal helminth Nippostrongylus brasiliensis (Nb) exhibit a transitory impairment of resistance to airborne Mtb infection. Furthermore, a second dose of Nb infection substantially increases the bacterial burden in the lungs of co-infected mice. Interestingly, the Th2 response in the co-infected animals did not impair the onset and development of the protective Mtb-specific Th1 cellular immune responses. However, the helminth-induced Th2 environment resulted in the accumulation of alternatively activated macrophages (AAMs) in the lung. Co-infected mice lacking interleukin (IL) 4Rα exhibited improved ability to control Mtb infection, which was accompanied by significantly reduced accumulation of AAMs. Moreover, IL-4Rα(-/-) mice adoptively transferred with wild-type macrophages had a significantly higher Mtb load in their lungs compared with those that received IL-4Rα(-/-) macrophages, suggesting a direct contribution for the IL-4R pathway to the heightened susceptibility of co-infected animals. The Th2 response can thus enhance the intracellular persistence of Mtb, in part by mediating the alternative activation of macrophages via the IL-4Rα signaling pathway."
] |
509 | Hematopoietic Stem Cell purification reaches purity rates above 90%. | [
"13980338"
] | [
"Combined Single-Cell Functional and Gene Expression Analysis Resolves Heterogeneity within Stem Cell Populations. Heterogeneity within the self-renewal durability of adult hematopoietic stem cells (HSCs) challenges our understanding of the molecular framework underlying HSC function. Gene expression studies have been hampered by the presence of multiple HSC subtypes and contaminating non-HSCs in bulk HSC populations. To gain deeper insight into the gene expression program of murine HSCs, we combined single-cell functional assays with flow cytometric index sorting and single-cell gene expression assays. Through bioinformatic integration of these datasets, we designed an unbiased sorting strategy that separates non-HSCs away from HSCs, and single-cell transplantation experiments using the enriched population were combined with RNA-seq data to identify key molecules that associate with long-term durable self-renewal, producing a single-cell molecular dataset that is linked to functional stem cell activity. Finally, we demonstrated the broader applicability of this approach for linking key molecules with defined cellular functions in another stem cell system."
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.