Effects of exercise intensity and nutrition advice on myocardial function in obese children and adolescents: a multicentre randomised controlled trial study protocol.

INTRODUCTION: The prevalence of paediatric obesity is increasing, and with it, lifestyle-related diseases in children and adolescents. High-intensity interval training (HIIT) has recently been explored as an alternate to traditional moderate-intensity continuous training (MICT) in adults with chronic disease and has been shown to induce a rapid reversal of subclinical disease markers in obese children and adolescents. The primary aim of this study is to compare the effects of HIIT with MICT on myocardial function in obese children and adolescents. METHODS AND ANALYSIS: Multicentre randomised controlled trial of 100 obese children and adolescents in the cities of Trondheim (Norway) and Brisbane (Australia). The trial will examine the efficacy of HIIT to improve cardiometabolic outcomes in obese children and adolescents. Participants will be randomised to (1) HIIT and nutrition advice, (2) MICT and nutrition advice or (3) nutrition advice. Participants will partake in supervised exercise training and/or nutrition sessions for 3 months. Measurements for study end points will occur at baseline, 3 months (postintervention) and 12 months (follow-up). The primary end point is myocardial function (peak systolic tissue velocity). Secondary end points include vascular function (flow-mediated dilation assessment), quantity of visceral and subcutaneous adipose tissue, myocardial structure and function, body composition, cardiorespiratory fitness, autonomic function, blood biochemistry, physical activity and nutrition. Lean, healthy children and adolescents will complete measurements for all study end points at one time point for comparative cross-sectional analyses. ETHICS AND DISSEMINATION: This randomised controlled trial will generate substantial information regarding the effects of exercise intensity on paediatric obesity, specifically the cardiometabolic health of this at-risk population. It is expected that communication of results will allow for the development of more effective evidence-based exercise prescription guidelines in this population while investigating the benefits of HIIT on subclinical markers of disease. TRIAL REGISTRATION NUMBER: NCT01991106

Normative data on regional sweat-sodium concentrations of professional male team-sport athletes

Background: The purpose of this paper was to report normative data on regional sweat sweat-sodium concentrations of various professional male team-sport athletes, and to compare sweat-sodium concentrations among sports. Data to this effect would inform our understanding of athlete sodium requirements, thus allowing for the individualisation of sodium replacement strategies. Accordingly, data from 696 athletes (Soccer, n = 270; Rugby, n = 181; Baseball, n = 133; American Football, n = 60; Basketball, n = 52) were compiled for a retrospective analysis. Regional sweat-sodium concentrations were collected using the pilocarpine iontophoresis method, and compared to self-reported measures collected via questionnaire. Results: Sweat-sodium concentrations were significantly higher (p < 0.05) in American football (50.4 ± 15.3 mmol·L-1), baseball (54.0 ± 14.0 mmol·L-1), and basketball (48.3 ± 14.0 mmol·L-1) than either soccer (43.2 ± 12.0 mmol·L-1) or rugby (44.0 ± 12.1 mmol·L-1), but with no differences among the N.American or British sports. There were strong positive correlations between sweat-sodium concentrations and self-reported sodium losses in American football (rs = 0.962, p < 0.001), basketball (rs = 0.953, p < 0.001), rugby (rs = 0.813, p < 0.001), and soccer (rs = 0.748, p < 0.001). Conclusions: The normative data provided on sweat-sodium concentrations might assist sports science/medicine practitioners in generating bespoke hydration and electrolyte-replacement strategies to meet the sodium demands of professional team-sport athletes. Moreover, these novel data suggest that self-reported measures of sodium loss might serve as an effective surrogate in the absence of direct measures; i.e., those which are more expensive or non-readily available

Duodenal carcinoma at the ligament of Treitz. A molecular and clinical perspective

Background There is very small occurrence of adenocarcinoma in the small bowel. We present a case of primary duodenal adenocarcinoma and discuss the findings of the case diagnostic modalities, current knowledge on the molecular biology behind small bowel neoplasms and treatment options. Case The patient had a history of iron deficiency anemia and occult bleeding with extensive workup consisting of upper endoscopy, colonoscopy, capsule endoscopy, upper gastrointestinal series with small bowel follow through and push enteroscopy. Due to persistent abdominal pain and iron deficiency anemia the patient underwent push enteroscopy which revealed adenocarcinoma of the duodenum. The patient underwent en-bloc duodenectomy which revealed T3N1M0 adenocarcinoma of the 4th portion of the duodenum. Conclusions Primary duodenal carcinoma, although rare should be considered in the differential diagnosis of occult gastrointestinal bleeding when evaluation of the lower and upper GI tract is unremarkable. We discuss the current evaluation and management of this small bowel neoplasm

Spatially distributed dendritic resonance selectively filters synaptic input

© 2014 Laudanski et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.An important task performed by a neuron is the selection of relevant inputs from among thousands of synapses impinging on the dendritic tree. Synaptic plasticity enables this by strenghtening a subset of synapses that are, presumably, functionally relevant to the neuron. A different selection mechanism exploits the resonance of the dendritic membranes to preferentially filter synaptic inputs based on their temporal rates. A widely held view is that a neuron has one resonant frequency and thus can pass through one rate. Here we demonstrate through mathematical analyses and numerical simulations that dendritic resonance is inevitably a spatially distributed property; and therefore the resonance frequency varies along the dendrites, and thus endows neurons with a powerful spatiotemporal selection mechanism that is sensitive both to the dendritic location and the temporal structure of the incoming synaptic inputs.Peer reviewe

Progression of the faecal microbiome in preweaning dairy calves that develop cryptosporidiosis

\ua9 The Author(s) 2024.Background: Cryptosporidiosis is a diarrheal disease that commonly affects calves under 6 weeks old. The causative agent, Cryptosporidium parvum, has been associated with the abundance of specific taxa in the faecal microbiome during active infection. However, the long-term impact of these microbiome shifts, and potential effects on calf growth and health have not yet been explored in depth. Methods: Three hundred and forty-six (346) calves from three dairy farms had one faecal swab collected during the first week of life (W1). Thereafter, sampled calves were monitored for diarrhoeal disease and those that suffered a diarrhoea event were tested for C. parvum by lateral flow testing (LFT). Calves that experienced diarrhoea and tested positive for C. parvum by LFT were assigned to the Cryptosporidium-positive (Cp+) group (n = 32). Matched healthy (H) controls with no history of diarrhoea were selected from the remaining cohort (n = 33). The selected subset of calves (n = 65) was observed until weaning, collecting a faecal swab, at approximately Week 5 (W5) and Week 10 (W10) after birth, resulting in a total of 191 samples (W1; n = 65, W5; n = 64, W10; n = 62). 16S rRNA gene amplicon sequencing was performed on all extracted samples. Results: Analysis of the longitudinal microbiome showed significant changes in the microbial diversity and composition across all three time-points. Whilst Firmicutes were elevated in the Cp+ group at W5 compared to the H group, no other significant differences were detected between H and Cp+ groups. Whilst the core microbiota showed some taxa were exclusive to each group, the role of these taxa in health and disease has yet to be determined. Antibiotics were also found to have an impact on the relative abundance of some taxa. Though healthy calves received a significantly higher body condition score than Cp+ calves at W5, the difference did not reach significance at W10, suggesting that Cp+ calves may catch up to their healthy counterparts once the infection has resolved. Conclusions: The findings of this study illustrated the changes in the microbial diversity and composition during the preweaning period in dairy calves. The results also indicated that the faecal microbiome is not predictive of cryptosporidiosis and implied that cryptosporidiosis doesn’t cause long-term gut dysbiosis. This study furthered our understanding of the parasite-microbiome relationship and its impact on the bovine host

Agreement between left and right middle cerebral artery blood velocity responses to incremental and constant work-rate exercise in healthy males and females

This is the author accepted manuscript. The final version is available from IOP Publishing via the DOI in this recordObjective: To quantify the agreement between left and right middle cerebral artery blood velocity (MCAv) responses to incremental and constant work-rate exercise in adults. Approach: Seventeen healthy adults (23.8±2.4 years, 9 females) completed a ramp incremental test to exhaustion on a cycle ergometer, three 6-minute transitions at a moderate-intensity, and three at a heavy-intensity, all on separate days. Bilateral MCAv was measured throughout using transcranial Doppler ultrasonography, with left and right MCAv data analysed separately. Data were analysed at baseline, gas exchange threshold, respiratory compensation point and exhaustion during ramp incremental exercise. MCAv responses to constant work-rate exercise were analysed using a mono-exponential model, to determine time- and amplitude-based kinetic response parameters. Main Results: Left and right MCAv responses to incremental and constant work-rate exercise were significantly, strongly and positively correlated (r≥0.61, P<0.01). Coefficient of variation (left vs right) ranged from 7.3-20.7%, 6.4-26.2% and 5.9-22.5% for ramp, moderate and heavy 33 intensity exercise, respectively. The relative change in MCAv from baseline was higher in the right compared to left MCAv during ramp, moderate and heavy-intensity exercise (all P<0.05), but the effect sizes were small (d≤0.4). Small mean left-right differences were present during ramp incremental exercise at all time-points (<6 cm/s; <4%), and for all kinetic parameters during moderate and heavy-intensity exercise (<3 cm/s, <3%, <4 s). Significance: These findings demonstrate similarities between left and right MCAv responses to incremental and constant-work rate exercise in adults on a group-level, but also highlight individual variation in the agreement between left and right MCAv exercise responsesQUEX Institut

The effect of exercise intensity and cardiorespiratory fitness on the kinetic response of middle cerebral artery blood velocity during exercise in adults

This is the final version. Available on open access from the American Physiological Society via the DOI in this recordThe aim of this study was to compare the kinetic response of middle cerebral artery blood velocity (MCAv) to moderate and heavy-intensity cycling in adults, and explore the relationship between maximal oxygen uptake (VO2max) and MCAv kinetics. Seventeen healthy adults (23.8±2.4 years, 9 females) completed a ramp incremental test to exhaustion on a cycle ergometer to determine VO2max and the gas exchange threshold (GET). Across six separate visits, participants completed three 6-minute transitions at a moderate-intensity (90% GET) and three at a heavy-intensity (40% of the difference between GET and VO2max). Bilateral MCAv was measured using transcranial Doppler ultrasonography and analysed using a mono-exponential model with a time delay. The time constant (τ) of the MCAv response was not different between moderate- and heavy-intensity cycling (25±10 vs. 26±8 s, P=0.82), as was the time delay (29±11 vs. 29±10 s, P=0.95). The amplitude of the exponential increase in MCAv from baseline was greater during heavy (23.9±10.0 cm.s-1, 34.1±14.4%) compared to moderate (12.7±4.4 cm.s-1, 18.7±7.5%) intensity cycling (P0.05). These data suggest that the intensity of constant-work rate exercise influences the amplitude, but not time-based, response parameters of MCAv in healthy adults, and found no relationship between cardiorespiratory fitness and MCAv kinetics.QUEX Institut

Inspiratory flow-resistive breathing, respiratory muscle-induced systemic oxidative stress, and diaphragm fatigue in healthy humans

We questioned whether the respiratory muscles of humans contribute to systemic oxidative stress following inspiratory flow-resistive breathing, whether the amount of oxidative stress is influenced by the level of resistive load, and whether the amount of oxidative stress is related to the degree of diaphragm fatigue incurred. Eight young and healthy participants attended the laboratory for four visits on separate days. During the first visit, height, body mass, lung function, and maximal inspiratory mouth and transdiaphragmatic pressure (Pdimax) were assessed. During visits 2–4, participants undertook inspiratory flow-resistive breathing with either no resistance (control) or resistive loads equivalent to 50 and 70% of their Pdimax (Pdimax50% and Pdimax70%) for 30 min. Participants undertook one resistive load per visit, and the order in which they undertook the loads was randomized. Inspiratory muscle pressures were higher (P < 0.05) during the 5th and Final min of Pdimax50% and Pdimax70% compared with control. Plasma F2-isoprostanes increased (P < 0.05) following inspiratory flow-resistive breathing at Pdimax70%. There were no increases in plasma protein carbonyls or total antioxidant capacity. Furthermore, although we evidenced small reductions in transdiapragmaic twitch pressures (PdiTW) after inspiratory flow-resistive breathing at Pdimax50% and Pdimax70%, this was not related to the increase in plasma F2-isoprostanes. Our novel data suggest that it is only when sufficiently strenuous that inspiratory flow-resistive breathing in humans elicits systemic oxidative stress evidenced by elevated plasma F2-isoprostanes, and based on our data, this is not related to a reduction in PdiTW