514 research outputs found
Insulin clearance and the incidence of type 2 diabetes in Hispanics and African Americans: the IRAS Family Study.
ObjectiveWe aimed to identify factors that are independently associated with the metabolic clearance rate of insulin (MCRI) and to examine the association of MCRI with incident type 2 diabetes in nondiabetic Hispanics and African Americans.Research design and methodsWe investigated 1,116 participants in the Insulin Resistance Atherosclerosis Study (IRAS) Family Study with baseline examinations from 2000 to 2002 and follow-up examinations from 2005 to 2006. Insulin sensitivity (S(I)), acute insulin response (AIR), and MCRI were determined at baseline from frequently sampled intravenous glucose tolerance tests. MCRI was calculated as the ratio of the insulin dose over the incremental area under the curve of insulin. Incident diabetes was defined as fasting glucose ≥126 mg/dL or antidiabetic medication use by self-report.ResultsWe observed that S(I) and HDL cholesterol were independent positive correlates of MCRI, whereas fasting insulin, fasting glucose, subcutaneous adipose tissue, visceral adipose tissue, and AIR were independent negative correlates (all P < 0.05) at baseline. After 5 years of follow-up, 71 (6.4%) participants developed type 2 diabetes. Lower MCRI was associated with a higher risk of incident diabetes after adjusting for demographics, lifestyle factors, HDL cholesterol, indexes of obesity and adiposity, and insulin secretion (odds ratio 2.01 [95% CI 1.30-3.10], P = 0.0064, per one-SD decrease in loge-transformed MCRI).ConclusionsOur data showed that lower MCRI predicts the incidence of type 2 diabetes
Comparing the effects of an acute bout of physical exercise with an acute bout of interactive mental and physical exercise on electrophysiology and executive functioning in younger and older adults
Background
Physical exercise has been shown to improve cognitive and neural functioning in older adults.
Aims and methods
The current study compared the effects of an acute bout of physical exercise with a bout of interactive mental and physical exercise (i.e., “exergaming”) on executive (Stroop) task performance and event-related potential (ERP) amplitudes in younger and older adults.
Results
Results revealed enhanced executive task performance in younger and older adults after exercise, with no differences in performance between exercise conditions. Stroop (RT) performance in older adults improved more than in younger adults from pre- to post-exercise. A significant increase in EEG amplitude from pre- to post-exercise was found at the Cz site from 320 to 700 ms post-stimulus for both younger and older adults, with older adults demonstrating a larger Stroop interference effect. While younger adults exhibited overall greater EEG amplitudes than older adults, they showed no differences between congruent and incongruent trials (i.e., minimal interference). Compared to peers with higher BMI (body mass index), older adults with lower BMI showed a greater reduction in Stroop interference effects from pre- to post-exercise.
Discussion and conclusions
The beneficial effects of an acute bout of physical exercise on cognitive and neural functioning in younger and older adults were confirmed, with no difference between standard exercise and exergaming. Findings suggest that BMI, sometimes used as a proxy for fitness level, may modulate benefits that older adults derive from an acute bout of exercise. Findings have implications for future research that seeks to investigate unique effects of exergaming when compared to standard physical exercise
Oedema extension distance in intracerebral haemorrhage: Association with baseline characteristics and long-term outcome
Introduction:
Oedema extension distance is a derived parameter that may reduce sample size requirements to demonstrate reduction in perihaematomal oedema in early phase acute intracerebral haemorrhage trials. We aimed to identify baseline predictors of oedema extension distance and its association with clinical outcomes.
Patients and methods:
Using Virtual International Stroke Trials Archive-Intracerebral Haemorrhage, first Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial, and Minimally Invasive Surgery and rtPA for Intracerebral Hemorrhage Evacuation II datasets, we calculated oedema extension distance at baseline and at 72 h measured using computed tomography. Using linear regression, we tested for associations between baseline characteristics and oedema extension distance at 72 h. Ordinal regression (underlying assumptions validated) was used to test for associations between oedema extension distance at baseline and 72 h and oedema extension distance change between baseline and 72 h, and modified Rankin scale scores at 90 days, adjusted for baseline and 72 h prognostic factors.
Results:
There were 1028 intracerebral haemorrhage cases with outcome data for analyses. Mean (standard deviation, SD) oedema extension distance at 72 h was 0.54 (0.26) cm, and mean oedema extension distance difference from baseline (EED72–0) was 0.24 (0.18) cm. Oedema extension distance at 72 h was greater with increasing baseline haematoma volume and baseline oedema extension distance. Increasing age, lobar haemorrhage, and intraventricular haemorrhage were independently associated with EED72–0. In multifactorial ordinal regression analysis, EED72–0 was associated with worse modified Rankin scale scores at 90 days (odds ratio 1.96, 95% confidence interval 1.00–3.82).
Discussion:
Increase in oedema extension distance over 72 h is independently associated with decreasing functional outcome at 90 days. Oedema extension distance may be a useful surrogate outcome measure in early phase trials of anti-oedema or anti-inflammatory treatments in intracerebral haemorrhage
Xenografting of human fetal testis tissue: a new approach to study fetal testis development and germ cell differentiation
Superhero comics and the digital communications circuit: a case study of <i>Strong Female Protagonist</i>
This article examines the ongoing superhero webcomic Strong Female Protagonist (2012-present), by Brannon Lee Mulligan and Molly Ostertag and employs it as a case study to analyse the new communications circuit created by the digital production and delivery of comics. It adopts a perspective drawn from Book History to frame the communication model of print comics and to evaluate how webcomics such as Strong Female Protagonist redefine the role of readers, authors and publishers
Happy Protest Voters: The Case of Rotterdam 1997–2009
Protest parties are on the rise in several European countries. This development is commonly attributed to a growing dissatisfaction with life and associated with declining quality of life in modern society of the lowest social strata. This explanation is tested in a cross-sectional analysis of voting and life-satisfaction in 63 districts of the city of Rotterdam in the Netherlands, where the share of protest voters increased from 10 % in 1994 to 31 % in 2009. Contrary to this explanation protest voting appeared not to be the most frequent in the least happy districts of Rotterdam, but in the medium happy segment. Also divergent from this explanation was that average happiness in city districts is largely independent of local living conditions, but is rather a matter of personal vulnerability in terms of education, income and health. These results fit alternative explanations in terms of mid
Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run
Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo’s third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours–months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets
Association of Alanine Aminotransferase Levels (ALT) with the Hepatic Insulin Resistance Index (HIRI): a cross-sectional study
The circadian clock protein REVERBα inhibits pulmonary fibrosis development
Pulmonary inflammatory responses lie under circadian control; however, the importance of circadian mechanisms in the underlying fibrotic phenotype is not understood. Here, we identify a striking change to these mechanisms resulting in a gain of amplitude and lack of synchrony within pulmonary fibrotic tissue. These changes result from an infiltration of mesenchymal cells, an important cell type in the pathogenesis of pulmonary fibrosis. Mutation of the core clock protein REVERBα in these cells exacerbated the development of bleomycin-induced fibrosis, whereas mutation of REVERBα in club or myeloid cells had no effect on the bleomycin phenotype. Knockdown of REVERBα revealed regulation of the little-understood transcription factor TBPL1. Both REVERBα and TBPL1 altered integrinβ1 focal-adhesion formation, resulting in increased myofibroblast activation. The translational importance of our findings was established through analysis of 2 human cohorts. In the UK Biobank, circadian strain markers (sleep length, chronotype, and shift work) are associated with pulmonary fibrosis, making them risk factors. In a separate cohort, REVERBα expression was increased in human idiopathic pulmonary fibrosis (IPF) lung tissue. Pharmacological targeting of REVERBα inhibited myofibroblast activation in IPF fibroblasts and collagen secretion in organotypic cultures from IPF patients, thus suggesting that targeting of REVERBα could be a viable therapeutic approach
Estimating the Accuracy of Anal Cytology in the Presence of an Imperfect Reference Standard
Background: The study aim is to estimate sensitivity and specificity of anal cytology for histologic HSIL in analyses adjusted for the imperfect biopsy reference standard. Methods and Principal Findings: Retrospective cohort study of an anal dysplasia screening program for HIV infected adults. We estimated the prevalence of histologic HSIL by concurrent cytology category and the associated cytology ROC area. Cytology operating characteristics for HSIL were estimated and adjusted for the imperfect reference standard by 3 methodologies. The study cohort included 261 patients with 3 available measures: (1) referral cytology; (2) HRA cytology; and (3) HRA directed biopsy. The prevalence of biopsy HSIL varied according to the concurrent HRA cytology result: 64.5
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