The shape of things : Male body image amongst South African University Students

This research explored trends in male body image amongst South African men aged 18 to 25 years. A questionnaire consisting of a demographic section, the Body Image Test, the Behaviours Checklist and the Eating Disorders Inventory was administered to 50 male students from the University of the Witwatersrand. Trends in body dissatisfaction, body enhancing behaviour and eating disorder symptoms were examined. Correlation analyses were used to infer relationships between these three variables. The results showed that the sample group on average view themselves as overly muscular and have a body image ideal that is less muscular than their perceived body image. This trend is contrary to trends reported in international studies and is thought to represent the cultural effects of using a South African population that is diverse in its composition as compared to an American or European samples that are more homogenous in nature. The results also showed that there were differences in body image trends between different racial groupings, although the results did indicate that across the racial groupings there was a similar societal body image ideal that represents a global trend towards a lean, muscular male body image. The results showed that the sample did not engage in body enhancing behaviours that are considered excessive or indicative of body image dissatisfaction. This was also reflected by the results on the Eating Disorders Inventory that showed considerably lower scores on the symptom scales when compared to a clinical eating disordered population and a non-clinical female comparison group. The results also showed that the sample had lower scores on the behavioural symptom scales yet higher scores on the attitudinal symptom scales. This indicates that the sample did not display any significant eating disorder behaviours yet did display personality traits that are correlated to eating disordered behaviour. There was no correlation between body dissatisfaction and body enhancing behaviour. There was a positive correlation between body dissatisfaction and the symptom scale of interpersonal distrust. A positive correlation also occurred between body enhancing behaviour and the symptom scales for perfection and drive for thinness. Limitations of the study and recommendations for future research are discussed

Differential Acute and Long Term Actions of Succinic Acid Monomethyl Ester Exposure on Insulin-Secreting BRIN-BD11 Cells

Esters of succinic acid are potent insulin secretagogues, and have been proposed as novel antidiabetic agents for type 2 diabetes. This study examines the effects of acute and chronic exposure to succinic acid monomethyl ester (SAM) on insulin secretion, glucose metabolism and pancreatic beta cell function using the BRIN-BD11 cell line. SAM stimulated insulin release in a dose-dependent manner at both non-stimulatory (1.1mM) and stimulatory (16.7mM) glucose. The depolarizing actions of arginine also stimulated a significant increase in SAM-induced insulin release but 2-ketoisocaproic acid (KIC) inhibited SAM induced insulin secretion indicating a possible competition between the preferential oxidative metabolism of these two agents. Prolonged (18hour) exposure to SAM revealed decreases in the insulin-secretory responses to glucose, KIC, glyceraldehyde and alanine. Furthermore, SAM diminished the effects of nonmetabolized secretagogues arginine and 3-isobutyl-1-methylxanthine (IBMX). While the ability of BRIN-BD11 cells to oxidise glucose was unaffected by SAM culture, glucose utilization was substantially reduced. Collectively, these data suggest that while SAM may enhance the secretory potential of non-metabolized secretagogues, it may also serve as a preferential metabolic fuel in preference to other important physiological nutrients and compromise pancreatic beta cell function following prolonged exposure

Impact of nocturnal hemodialysis on the variability of heart rate and duration of hypoxemia during sleep

Impact of nocturnal hemodialysis on the variability of heart rate and duration of hypoxemia during sleep.BackgroundNocturnal hemodialysis (NHD) alleviates uremia-related sleep apnea, a condition characterized by increased sympathetic activity and diminished heart rate (HR) variability. We tested the hypothesis that NHD reduces both hypoxemia and sympathetic neural contributions to HR variability during sleep.MethodsEpisodes of apnea and hypopnea and the duration of nocturnal hypoxemia during sleep were determined in 9 end-stage renal disease (ESRD) patients (age: 44 ± 2) (mean ± SEM) before and after conversion from conventional hemodialysis (CHD) to NHD, and in 10 control subjects (age: 45 ± 3) with normal renal function and without sleep apnea. Low frequency (LF) (0.05-0.15 Hz) and high frequency (HF) (0.15-0.5 Hz) HR spectral power during stage 2 sleep was calculated (Fast Fourier transformation). Patients were studied 4 times (1day before and on the night after their CHD session) and 6–15months after conversion to NHD, while receiving NHD and on a non-dialysis night.ResultsNHD decreased the frequency of apnea and hypopnea (from 29.7 ± 9.3 to 8.2 ± 2.0 episodes per hour, P = 0.02), and duration of nocturnal hypoxemia (from 13.9 ± 5.2 to 2.6 ± 1.9% of total sleep time, P = 0.02). As CHD recipients, ESRD patients had faster nocturnal heart rates (79 ± 2 vs. 58 ± 1min-1, P = 0.03) and lower HF (vagal) (78 ± 27 vs. 6726 ± 4556ms2, P = 0.001) spectral power than control subjects. After conversion to NHD, HR fell (from 79 ± 2 to 66 ± 1min-1, P = 0.03) and HF power increased (from 78 ± 27 to 637 ± 139ms2, P = 0.001). The HF/HF+LF ratio, an index of vagal HR modulation, was lower during CHD (0.16 ± 0.03 vs. 0.42 ± 0.05 in control subjects, P < 0.05) and increased (to 0.45 ± 0.05, P < 0.001) after conversion to NHD. The LF/HF ratio, a representation of sympathetic HR modulation, which was significantly higher during CHD than in control subjects (2.77 ± 0.82 vs. 0.71 ± 0.11, P < 0.05), was also normalized by NHD (0.74 ± 0.12, P < 0.05, compared with CHD).ConclusionHigher heart rates and impaired vagal and augmented sympathetic HR modulation during sleep in ESRD patients are normalized by NHD. Potential mechanisms for these observations include attenuation of surges in sympathetic outflow elicited by apnea and hypoxia during sleep, normalization of nocturnal breathing patterns that influence HRV, and removal, by increased dialysis, of a sympatho-excitatory stimulus of renal origin

Space-time clustering of childhood central nervous system tumours in Yorkshire, UK

<p>Abstract</p> <p>Background</p> <p>We specifically tested the aetiological hypothesis that a factor influencing geographical or temporal heterogeneity of childhood central nervous system (CNS) tumour incidence was related to exposure to a transient environmental agent.</p> <p>Methods</p> <p>Information was extracted on individuals aged 0-14 years, diagnosed with a CNS tumour between the 1st January 1974 and 31st December 2006 from the Yorkshire Specialist Register of Cancer in Children and Young People. Ordnance Survey eight-digit grid references were allocated to each case with respect to addresses at the time of birth and the time of diagnosis, locating each address to within 0.1 km. The following diagnostic groups were specified <it>a priori </it>for analysis: ependymoma; astrocytoma; primitive neuroectodermal tumours (PNETs); other gliomas; total CNS tumours. We applied the <it>K</it>-function method for testing global space-time clustering using fixed geographical distance thresholds. Tests were repeated using variable nearest neighbour (NN) thresholds.</p> <p>Results</p> <p>There was statistically significant global space-time clustering for PNETs only, based on time and place of diagnosis (<it>P </it>= 0.03 and 0.01 using the fixed geographical distance and the variable NN threshold versions of the <it>K</it>-function method respectively).</p> <p>Conclusions</p> <p>There was some evidence for a transient environmental component to the aetiology of PNETs. However, a possible role for chance cannot be excluded.</p

Dataset for 'A highly active mineral-based ice nucleating agent supports in situ cell cryopreservation in a high throughput format'

Cryopreservation of biological matter in microlitre scale volumes of liquid would be useful for a range of applications. At present, it is challenging because small volumes of water tend to supercool, and deep supercooling is known to lead to poor post thaw cell viability. Here we show that a mineral ice nucleator can almost eliminate supercooling in 100 microlitre liquid volumes during cryopreservation. This strategy of eliminating supercooling greatly enhances cell viability relative to cryopreservation protocols with uncontrolled ice nucleation. Using infrared thermography, we demonstrate a direct relationship between extent of supercooling and post-thaw cell viability. Using a mineral nucleator delivery system we open the door to the routine cryopreservation of mammalian cells in multiwell plates for applications such as high throughput toxicology testing of pharmaceutical products and regenerative medicine

After-exercise heart rate variability is attenuated in postmenopausal women and unaffected by estrogen therapy

Delayed heart rate (HR) recovery in the immediate postexercise period has been linked to adverse cardiovascular prognosis. The after effects of an acute bout of exercise on HR modulation in postmenopausal women (PMW) and the influence of estrogen therapy are unknown.In 13 sedentary PMW (54 ± 2 y, mean ± SEM), we assessed HR variability (HRV) -an index of HR modulation-and the influence of estrogen therapy on HRV. HRV in the frequency domain was quantified during supine rest and again 60 minutes after treadmill exercise for 45 minutes, at 60% VO2peak. PMW were studied before and after 4 weeks of oral estradiol. To obtain reference values for the after effects of exercise on HRV in healthy young women, 14 premenopausal women (PreM) completed the identical exercise protocol.Compared with PreM, PMW demonstrated lower high frequency (vagal modulation) and total HRV (P < 0.05) at rest. In PreM, all HRV values were similar before and after exercise. In contrast, in PMW after exercise, despite having identical HR to PreM, high frequency and total HRV were all lower (all P ≤ 0.01) compared with pre-exercise HRV values. Estrogen therapy had no effect on pre or postexercise values for HRV.When compared with PreM, PMW have identical HR, but lower vagal HR modulation at rest and delayed HRV recovery after exercise. Estrogen does not restore baseline HRV or accelerate HRV recovery postexercise, suggesting aging rather than estrogen deficiency per se may lower HRV in PMW

Diverse Durham collection phages demonstrate complex BREX defence responses

Bacteriophages (phages) outnumber bacteria ten-to-one and cause infections at a rate of 1025 per second. The ability of phages to reduce bacterial populations makes them attractive alternative antibacterials for use in combating the rise in antimicrobial resistance. This effort may be hindered due to bacterial defenses such as Bacteriophage Exclusion (BREX) that have arisen from the constant evolutionary battle between bacteria and phages. For phages to be widely accepted as therapeutics in Western medicine, more must be understood about bacteria–phage interactions and the outcomes of bacterial phage defense. Here, we present the annotated genomes of 12 novel bacteriophage species isolated from water sources in Durham, UK, during undergraduate practical classes. The collection includes diverse species from across known phylogenetic groups. Comparative analyses of two novel phages from the collection suggest they may be founding members of a new genus. Using this Durham phage collection, we determined that particular BREX defense systems were likely to confer a varied degree of resistance against an invading phage. We concluded that the number of BREX target motifs encoded in the phage genome was not proportional to the degree of susceptibility

Heritability and genetic correlations of heart rate variability at rest and during stress in the Oman Family Study

Introduction:Individual differences in heart rate variability (HRV) can be partly attributed to genetic factors that may be more pronounced during stress. Using data from the Oman Family Study (OFS), we aimed to estimate and quantify the relative contribution of genes and environment to the variance of HRV at rest and during stress; calculate the overlap in genetic and environmental influences on HRV at rest and under stress using bivariate analyses of HRV parameters and heart rate (HR).Methods:Time and frequency domain HRV variables and average HR were measured from beat-to-beat HR obtained from electrocardiogram recordings at rest and during two stress tests [mental: Word Conflict Test (WCT) and physical: Cold Pressor Test (CPT)] in the OFS - a multigenerational pedigree consisting of five large Arab families with a total of 1326 participants. SOLAR software was used to perform quantitative genetic modelling.Results:Heritability estimates for HRV and HR ranged from 0.11 to 0.31 for rest, 0.09-0.43 for WCT, and 0.07-0.36 for CPT. A large part of the genetic influences during rest and stress conditions were shared with genetic correlations ranging between 0.52 and 0.86 for rest-WCT and 0.60-0.92 for rest-CPT. Nonetheless, genetic rest-stress correlations for most traits were significantly smaller than 1 indicating some stress-specific genetic effects.Conclusion:Genetic factors significantly influence HRV and HR at rest and under stress. Most of the genetic factors that influence HRV at rest also influence HRV during stress tests, although some unique genetic variance emerges during these challenging conditions

Epigenetic mechanisms, T-cell activation, and CCR5 genetics interact to regulate T-cell expression of CCR5, the major HIV-1 coreceptor.

CAPRISA, 2015.Abstract available in pdf

H2S biosynthesis and catabolism: new insights from molecular studies

Hydrogen sulfide (H2S) has profound biological effects within living organisms and is now increasingly being considered alongside other gaseous signalling molecules, such as nitric oxide (NO) and carbon monoxide (CO). Conventional use of pharmacological and molecular approaches has spawned a rapidly growing research field that has identified H2S as playing a functional role in cell-signalling and post-translational modifications. Recently, a number of laboratories have reported the use of siRNA methodologies and genetic mouse models to mimic the loss of function of genes involved in the biosynthesis and degradation of H2S within tissues. Studies utilising these systems are revealing new insights into the biology of H2S within the cardiovascular system, inflammatory disease, and in cell signalling. In light of this work, the current review will describe recent advances in H2S research made possible by the use of molecular approaches and genetic mouse models with perturbed capacities to generate or detoxify physiological levels of H2S gas within tissue