570 research outputs found
Expression of GAD67 and Novel GAD67 Splice Variants During Human Fetal Pancreas Development: GAD67 Expression in the Fetal Pancreas
Glutamic acid decarboxylase (GAD) is a major inhibitory neurotransmitter in the brain, which catalyses the reaction of l-glutamate to γ-aminobutyric acid. There are two isoforms of GAD, a 65-kDa form and a 67-kDa form, which are encoded by two different genes. As previous studies suggested a role for GAD67 splice variants during fetal pancreas development, we have investigated the mRNA expression of GAD67 and GAD67 splice variants in a series of 14 human fetal pancreases between 14 weeks gestation and term and in adult control pancreases by RT-PCR. In this study, we demonstrate mRNA expression of GAD67 and four GAD67 splice variants, including GAD25, in human fetal and adult specimens. Some of the splice variants, including various proportions of exon 7 or a new exon between exons 6 and 7, have not been described before in the human pancreas. We speculate that the expression of these GAD67 splice variants might be related to human fetal pancreas development
Effects of sex, age, and visits on receipt of preventive healthcare services: a secondary analysis of national data
BACKGROUND: Sex and age may exert a combined influence on receipt of preventive services with differences due to number of ambulatory care visits. METHODS: We used nationally representative data to determine weighted percentages and adjusted odds ratios of men and women stratified by age group who received selected preventive services. The presence of interaction between sex and age group was tested using adjusted models and retested after adding number of visits. RESULTS: Men were less likely than women to have received blood pressure screening (aOR 0.44;0.40–0.50), cholesterol screening (aOR 0.72;0.65–0.79), tobacco cessation counseling (aOR 0.66;0.55–0.78), and checkups (aOR 0.53;0.49–0.57). In younger age groups, men were particularly less likely than women to have received these services. In adjusted models, this observed interaction between sex and age group persisted only for blood pressure measurement (p = .016) and routine checkups (p < .001). When adjusting for number of visits, the interaction of age on receipt of blood pressure checks was mitigated but men were still overall less likely to receive the service. CONCLUSION: Men are significantly less likely than women to receive certain preventive services, and younger men even more so. Some of this discrepancy is secondary to a difference in number of ambulatory care visits
RsaI repetitive DNA in Buffalo Bubalus bubalis representing retrotransposons, conserved in bovids, are part of the functional genes
<p>Abstract</p> <p>Background</p> <p>Repetitive sequences are the major components of the eukaryotic genomes. Association of these repeats with transcribing sequences and their regulation in buffalo <it>Bubalus bubalis </it>has remained largely unresolved.</p> <p>Results</p> <p>We cloned and sequenced <it>RsaI </it>repeat fragments pDp1, pDp2, pDp3, pDp4 of 1331, 651, 603 and 339 base pairs, respectively from the buffalo, <it>Bubalus bubalis</it>. Upon characterization, these fragments were found to represent retrotransposons and part of some functional genes. The resultant clones showed cross hybridization only with buffalo, cattle, goat and sheep genomic DNA. Real Time PCR, detected ~2 × 10<sup>4 </sup>copies of pDp1, ~ 3000 copies of pDp2 and pDp3 and ~ 1000 of pDp4 in buffalo, cattle, goat and sheep genomes, respectively. <it>RsaI </it>repeats are transcriptionally active in somatic tissues and spermatozoa. Accordingly, pDp1 showed maximum expression in lung, pDp2 and pDp3 both in Kidney, and pDp4 in ovary. Fluorescence <it>in situ </it>hybridization showed repeats to be distributed all across the chromosomes.</p> <p>Conclusions</p> <p>The data suggest that <it>RsaI </it>repeats have been incorporated into the exonic regions of various transcribing genes, possibly contributing towards the architecture and evolution of the buffalo and related genomes. Prospects of our present work in the context of comparative and functional genomics are highlighted.</p
Changes in body weight, body composition and cardiovascular risk factors after long-term nutritional intervention in patients with severe mental illness: an observational study
<p>Abstract</p> <p>Background</p> <p>Compared with the general population, individuals with severe mental illness (SMI) have increased prevalence rates of obesity and greater risk for cardiovascular disease. This study aimed to investigate the effects of a long term nutritional intervention on body weight, body fat and cardiovascular risk factors in a large number of patients with SMI.</p> <p>Methods</p> <p>Nine hundred and eighty-nine patients with a mean ± S.D age of 40 ± 11.7 yrs participated in a 9 mo nutritional intervention which provided personalised dietetic treatment and lifestyle counselling every two weeks. Patients had an average body mass index (BMI) of 34.3 ± 7.1 kg.m<sup>-2 </sup>and body weight (BW) of 94.9 ± 21.7 kg. Fasted blood samples were collected for the measurement of glucose, total cholesterol, triglycerides and HDL- cholesterol. All measurements were undertaken at baseline and at 3 mo, 6 mo and 9 mo of the nutritional intervention.</p> <p>Results</p> <p>Four hundred and twenty-three patients of 989 total patients' cases (42.8%) dropped out within the first 3 months. Two hundred eighty-five completed 6 months of the program and 145 completed the entire 9 month nutritional intervention. There were progressive statistically significant reductions in mean weight, fat mass, waist and BMI throughout the duration of monitoring (p < 0.001). The mean final weight loss was 9.7 kg and BMI decreased to 30.7 kg.m<sup>-2 </sup>(p < 0.001). The mean final fat mass loss was 8.0 kg and the mean final waist circumference reduction was 10.3 cm (p < 0.001) compared to baseline. Significant and continual reductions were observed in fasting plasma glucose, total cholesterol and triglycerides concentrations throughout the study (p < 0.001).</p> <p>Conclusion</p> <p>The nutritional intervention produced significant reductions in body weight, body fat and improved the cardiometabolic profile in patients with SMI. These findings indicate the importance of weight-reducing nutritional intervention in decreasing the cardiovascular risk in patients with SMI.</p
Age differences in physiological responses to self-paced and incremental testing
Purpose: A self-paced maximal exercise protocol has demonstrated higher values when compared against traditional tests. The aim was to compare physiological responses to this self-paced protocol (SPV) in comparison to a traditional ramp (RAMP) protocol in young (18–30 years) and old (50–75 years) participants. Methods: Forty-four participants (22 young; 22 old) completed both protocols in a randomised, counter-balanced, crossover design. The SPV included 5 × 2 min stages, participants were able to self-regulate their power output (PO) by using incremental ‘clamps’ in ratings of perceived exertion. The RAMP consisted of either 15 or 20 W min. Results: Expired gases, cardiac output (Q), stroke volume (SV), muscular deoxyhaemoglobin (deoxyHb) and electromyography (EMG) at the vastus lateralis were recorded throughout. Results demonstrated significantly higher in the SPV (49.68 ± 10.26 ml kg min) vs. the RAMP (47.70 ± 9.98 ml kg min) in the young, but not in the old group (>0.05). Q and SV were significantly higher in the SPV vs. the RAMP in the young (0.05). No differences seen in deoxyHb and EMG for either age groups (>0.05). Peak PO was significantly higher in the SPV vs. the RAMP in both age groups (<0.05). Conclusion: Findings demonstrate that the SPV produces higher , peak Q and SV values in the young group. However, older participants achieved similar values in both protocols, mostly likely due to age-related differences in cardiovascular responses to incremental exercise, despite them achieving a higher physiological workload in the SPV
The Evolution of Compact Binary Star Systems
We review the formation and evolution of compact binary stars consisting of
white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and
BHs are thought to be the primary astrophysical sources of gravitational waves
(GWs) within the frequency band of ground-based detectors, while compact
binaries of WDs are important sources of GWs at lower frequencies to be covered
by space interferometers (LISA). Major uncertainties in the current
understanding of properties of NSs and BHs most relevant to the GW studies are
discussed, including the treatment of the natal kicks which compact stellar
remnants acquire during the core collapse of massive stars and the common
envelope phase of binary evolution. We discuss the coalescence rates of binary
NSs and BHs and prospects for their detections, the formation and evolution of
binary WDs and their observational manifestations. Special attention is given
to AM CVn-stars -- compact binaries in which the Roche lobe is filled by
another WD or a low-mass partially degenerate helium-star, as these stars are
thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure
Symplasmic transport and phloem loading in gymnosperm leaves
Despite more than 130 years of research, phloem loading is far from being understood in gymnosperms. In part this is due to the special architecture of their leaves. They differ from angiosperm leaves among others by having a transfusion tissue between bundle sheath and the axial vascular elements. This article reviews the somewhat inaccessible and/or neglected literature and identifies the key points for pre-phloem transport and loading of photoassimilates. The pre-phloem pathway of assimilates is structurally characterized by a high number of plasmodesmata between all cell types starting in the mesophyll and continuing via bundle sheath, transfusion parenchyma, Strasburger cells up to the sieve elements. Occurrence of median cavities and branching indicates that primary plasmodesmata get secondarily modified and multiplied during expansion growth. Only functional tests can elucidate whether this symplasmic pathway is indeed continuous for assimilates, and if phloem loading in gymnosperms is comparable with the symplasmic loading mode in many angiosperm trees. In contrast to angiosperms, the bundle sheath has properties of an endodermis and is equipped with Casparian strips or other wall modifications that form a domain border for any apoplasmic transport. It constitutes a key point of control for nutrient transport, where the opposing flow of mineral nutrients and photoassimilates has to be accommodated in each single cell, bringing to mind the principle of a revolving door. The review lists a number of experiments needed to elucidate the mode of phloem loading in gymnosperms
A review on boiling heat transfer enhancement with nanofluids
There has been increasing interest of late in nanofluid boiling and its use in heat transfer enhancement. This article covers recent advances in the last decade by researchers in both pool boiling and convective boiling applications, with nanofluids as the working fluid. The available data in the literature is reviewed in terms of enhancements, and degradations in the nucleate boiling heat transfer and critical heat flux. Conflicting data have been presented in the literature on the effect that nanofluids have on the boiling heat-transfer coefficient; however, almost all researchers have noted an enhancement in the critical heat flux during nanofluid boiling. Several researchers have observed nanoparticle deposition at the heater surface, which they have related back to the critical heat flux enhancement
Sarcolemma-localized nNOS is required to maintain activity after mild exercise
Many neuromuscular conditions are characterized by an exaggerated exercise- induced fatigue response that is disproportionate to activity level. This fatigue is not necessarily correlated with greater central or peripheral fatigue in patients(1), and some patients experience severe fatigue without any demonstrable somatic disease(2). Except in myopathies that are due to specific metabolic defects, the mechanism underlying this type of fatigue remains unknown(2). With no treatment available, this form of inactivity is a major determinant of disability(3). Here we show, using mouse models, that this exaggerated fatigue response is distinct from a loss in specific force production by muscle, and that sarcolemma-localized signalling by neuronal nitric oxide synthase ( nNOS) in skeletal muscle is required to maintain activity after mild exercise. We show that nNOS- null mice do not have muscle pathology and have no loss of muscle- specific force after exercise but do display this exaggerated fatigue response to mild exercise. In mouse models of nNOS mislocalization from the sarcolemma, prolonged inactivity was only relieved by pharmacologically enhancing the cGMP signal that results from muscle nNOS activation during the nitric oxide signalling response to mild exercise. Our findings suggest that the mechanism underlying the exaggerated fatigue response to mild exercise is a lack of contraction- induced signalling from sarcolemma- localized nNOS, which decreases cGMP- mediated vasomodulation in the vessels that supply active muscle after mild exercise. Sarcolemmal nNOS staining was decreased in patient biopsies from a large number of distinct myopathies, suggesting a common mechanism of fatigue. Our results suggest that patients with an exaggerated fatigue response to mild exercise would show clinical improvement in response to treatment strategies aimed at improving exercise- induced signalling.Paul D. Wellstone Muscular Dystrophy Cooperative Research Center Grant ; University of Iowa Cardiovascular Interdisciplinary Research ; National Research Service Award ; National Institute of Arthritis and Musculoskeletal and Skin Diseases ; National Institutes of Health ; Senator Paul D. Wellstone Fellowship ; Muscular Dystrophy Association Development Grant ; Howard Hughes Medical InstituteWe thank M. Anderson and M. Henry for comments, and M. M. Kilburg, K. Uppal, B. J. Steinmann and S. Watkins and members of the Campbell laboratory for scientific contributions. This work was supported in part by a Paul D. Wellstone Muscular Dystrophy Cooperative Research Center Grant. Y.M.K. was supported by grants from the University of Iowa Cardiovascular Interdisciplinary Research/ National Research Service Award (NRSA) Fellowship, from an individual NRSA Fellowship from the National Institute of Arthritis and Musculoskeletal and Skin Diseases, from the National Institutes of Health (NIH), and from a Senator Paul D. Wellstone Fellowship. E.P.R. was supported by a Muscular Dystrophy Association Development Grant. R.M.W. was supported by the NIH. K.P.C. is an investigator of the Howard Hughes Medical Institute.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62850/1/nature07414.pd
RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome
<p>Abstract</p> <p>Background</p> <p>RNA-Seq is revolutionizing the way transcript abundances are measured. A key challenge in transcript quantification from RNA-Seq data is the handling of reads that map to multiple genes or isoforms. This issue is particularly important for quantification with de novo transcriptome assemblies in the absence of sequenced genomes, as it is difficult to determine which transcripts are isoforms of the same gene. A second significant issue is the design of RNA-Seq experiments, in terms of the number of reads, read length, and whether reads come from one or both ends of cDNA fragments.</p> <p>Results</p> <p>We present RSEM, an user-friendly software package for quantifying gene and isoform abundances from single-end or paired-end RNA-Seq data. RSEM outputs abundance estimates, 95% credibility intervals, and visualization files and can also simulate RNA-Seq data. In contrast to other existing tools, the software does not require a reference genome. Thus, in combination with a de novo transcriptome assembler, RSEM enables accurate transcript quantification for species without sequenced genomes. On simulated and real data sets, RSEM has superior or comparable performance to quantification methods that rely on a reference genome. Taking advantage of RSEM's ability to effectively use ambiguously-mapping reads, we show that accurate gene-level abundance estimates are best obtained with large numbers of short single-end reads. On the other hand, estimates of the relative frequencies of isoforms within single genes may be improved through the use of paired-end reads, depending on the number of possible splice forms for each gene.</p> <p>Conclusions</p> <p>RSEM is an accurate and user-friendly software tool for quantifying transcript abundances from RNA-Seq data. As it does not rely on the existence of a reference genome, it is particularly useful for quantification with de novo transcriptome assemblies. In addition, RSEM has enabled valuable guidance for cost-efficient design of quantification experiments with RNA-Seq, which is currently relatively expensive.</p
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