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Methods: Five electronic databases (PubMed (Medline), Web of Science, Embase, Sport Discus, and Cochrane Library) were searched for controlled trials that assessed the MPS response to RE in healthy, adult humans, postabsorptive state. Individual study and random-effects meta-analysis arewere used to inform the effects of RE and covariates on MPS. Results from 79 controlled trials with 237 participants were analysed., Results: Analysis of the pooled effects revealed robust increases in MPS following RE (weighted mean difference (WMD): 0.032% h -1 , 95% CI: [0.024, 0.041] % h -1 , I 2  = 92%, k  = 37, P < 0.001). However, the magnitude of the increase in MPS was lower in older adults (>50 y: WMD: 0.015% h -1 , 95% CI: [0.007, 0.022] % h -1 , I 2  = 76%, k  = 12, P = 0.002) compared to younger adults (<35 y: WMD: 0.041% h -1 , 95% CI: [0.030, 0.052] % h -1 , I 2  = 88%, k  = 25, P < 0.001). Individual studies have reported that the temporal proximity of the RE, muscle group, muscle protein fraction, RE training experience, and the loading parameters of the RE (i.e., intensity, workload, and effort) appeared to affect the MPS response to RE, whereas sex or type of muscle contraction does not., Conclusion: A single bout of RE can sustain measurable increases in postabsorptive MPS soon after RE cessation and up to 48 h post-RE. However, there is substantial heterogeneity in the magnitude and time course of the MPS response between trials, which appears to be influenced by participants' age and/or the loading parameters of the RE itself., Competing Interests: The authors declare that they have no conflicts of interest related to the work submitted for publication., (Copyright © 2024 Robert W. Davies et al.)

Purpose: To compare the effects of bilateral strength training (BLST) versus unilateral strength training (ULST) on changes in peak force (PF) and interlimb asymmetry (ILA) in the isometric squat at a 120° knee angle (ISq120)., Method: A total of 31 young, recreationally strength-trained men performed either BLST (n = 18) or ULST (n = 13), twice per week for 6 weeks. The total number of repetitions, duty cycle, and effort were standardized between training groups (ie, differing only in the exercises performed). Changes in PF and ILA were assessed pretraining and posttraining., Results: Comparable increases in PF were observed in the BLST group (mean [SD] change; 17.4% [20.5%], P = .001, standardized mean difference [SMD] = 0.45) and the ULST group (11.4% [19.1%], P = .042, SMD = 0.25). No significant changes in symmetry index (SI) scores were observed following BLST (mean [SD] change; 0 [5.7], P = .526, SMD = -0.12) or ULST (+3 [6.0], P = .702, SMD = 0.4). Individual analyses of subjects with marked ILA (ie, baseline SI score > baseline coefficient of variation) revealed a trend toward BLST being more effective at attenuating SI scores in the ISq120., Conclusions: Overall, both BLST and ULST are effective for increasing ISq120 PF. However, it appears that BLST may be more effective at reducing SI scores in those with marked ILA.

Disruptions to reproductive health in wildlife species inhabiting polluted environments is often found to occur alongside compromised immunity. However, research on impacts of aquatic pollution on freshwater mollusc immune responses is limited despite their importance as vectors of disease (Schistosomiasis) in humans, cattle and wild mammals. We developed an in vitro 'tool-kit' of well-characterized quantitative immune tests using Biomphalaria glabrata hemocytes. We exposed hemocytes to environmentally-relevant concentrations of common aquatic pollutants (17β-estradiol, Bisphenol-A and p,p'-DDE) and measured key innate immune responses including motility, phagocytosis and encapsulation. Additionally, we tested an extract of a typical domestic tertiary treated effluent as representative of a 'real-world' mixture of chemicals. Encapsulation responses were stimulated by p,p'-DDE at low doses but were suppressed at higher doses. Concentrations of BPA (above 200 ng/L) and p,p'-DDE (above 500 ng/L) significantly inhibited phagocytosis compared to controls, whilst hemocyte motility was reduced by all test chemicals and the effluent extract in a dose-dependent manner. All responses occurred at chemical concentrations considered to be below the cytotoxic thresholds of hemocytes. This is the first time a suite of in vitro tests has been developed specifically in B. glabrata with the purpose of investigating the impacts of chemical pollutants and an effluent extract on immunity. Our findings indicate that common aquatic pollutants alter innate immune responses in B. glabrata , suggesting that pollutants may be a critical, yet overlooked, factor impacting disease by modulating the dynamics of parasite transmission between molluscs and humans., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lynch, Noble, Jones and Routledge.)

The aim of the present study was to evaluate the effect of feeding fava bean ( Vicia faba L.) protein (FBP) on resting and post-exercise myofibrillar fractional synthetic rate (myoFSR). In a parallel, double-blind, randomised control trial, sixteen young, healthy recreationally active adults (age = 25 (5) years, body mass = 70 (15) kg, stature = 1.72 (0.11) m, mean (SD)) ingested 0.33 g·kg -1 FBP ( n = 8) or a negative control (CON, i.e., EAA-free mixture) ( n = 8), immediately after a bout of unilateral knee-extensor resistance exercise. Plasma, saliva, and m. vastus lateralis muscle samples were obtained pre-ingestion and 3 h post-ingestion. MyoFSR was calculated via deuterium labelling of myofibrillar-bound alanine, measured by gas chromatography-pyrolysis-isotope ratio mass spectrometry (GC-Pyr-IRMS). Resistance exercise increased myoFSR ( p = 0.012). However, ingestion of FBP did not evoke an increase in resting (FBP 29 [-5, 63] vs. CON 12 [-25, 49]%, p = 0.409, mean % change [95% CI]) or post-exercise (FBP 78 [33, 123]% vs. CON 58 [9, 107]%, p = 0.732) myoFSR. Ingestion of 0.33 g·kg -1 of FBP does not appear to enhance resting or post-exercise myoFSR in young, healthy, recreationally active adults.

Abstract: Nolan, D, Lynch, AE, and Egan, B. Self-reported prevalence, magnitude, and methods of rapid weight loss in male and female competitive powerlifters. J Strength Cond Res 36(2): 405-410, 2022-Rapid weight loss (RWL) is common practice in weight category sports, but no empirical data exist documenting the weight-making practices of competitive strength athletes. This study investigated the self-reported prevalence, magnitude, and methods of RWL used by male and female powerlifters when preparing for competition. Competitive powerlifters (n = 321; M/F, 194/127) completed an anonymous online questionnaire previously validated for assessment of methods of RWL. Respondents were categorized by their federation's respective antidoping policy, weigh-in procedure, and degree of assistive equipment allowed, in addition to their use or not of RWL. Subgroup analyses were performed on the largest category of respondents (n = 200, M/F, 117/83; ≤2-hour weigh-in, drug-tested, "raw") based on sex, weight category, and competitive status. Prevalence of RWL was 85.8%, with an average RWL of 3.0 ± 1.9% body mass and an RWL score of 25.1 ± 7.4. Neither sex nor weight category influenced the RWL score, but in male athletes, a lower RWL score (22.7 ± 6.3) was reported in athletes in the lowest tertile of the Wilks score (p = 0.015). Frequencies of "always use" were reported as 54.0% for fluid restriction and 49.0% for water loading. Coaches (37.5%) and online resources (35.0%) were "very influential" on RWL practices in these athletes, while doctors (85.5%) and dieticians (63.0%) were reported to be "not influential." The prevalence of RWL is high in competitive powerlifting, and the methods used are akin to other weight category sports, but the reported RWL scores are lower than reported in combat sports with longer recovery periods after weigh-in., (Copyright © 2020 National Strength and Conditioning Association.)

This study aimed to investigate the test-retest reliability of peak force in the isometric squat across the strength spectrum using coefficient of variation (CV) and intra-class correlation coefficient (ICC). On two separate days, 59 healthy men (mean (SD) age 23.0 (4.1) years; height 1.79 (0.7) m; body mass 84.0 (15.2) kg) performed three maximal effort isometric squats in two positions (at a 120° and a 90° knee angle). Acceptable reliability was observed at both the 120° (CV = 7.5 (6.7), ICC = 0.960 [0.933, 0.977]) and 90° positions (CV = 9.2 (8.8), ICC = 0.920 [0.865, 0.953]). There was no relationship between peak force in the isometric squat and the test-retest reliability at either the 120° (r = 0.052, p = 0.327) or 90° (r = 0.014, p = 0.613) positions. A subgroup of subjects (n = 17) also completed the isometric squat test at a 65° knee angle. Acceptable reliability was observed in this position (CV = 9.6 (9.3), ICC = 0.916 [0.766, 0.970]) and reliability was comparable to the 120° and 90° positions. Therefore, we deem isometric squat peak force output to be a valid and reliable measure across the strength spectrum and in different isometric squat positions.

Background: The primary objective was to determine the association of patient-reported vision-specific quality of life to disease status and visual function in patients with Friedreich's ataxia (FRDA)., Methods: Patients with FRDA were assessed with the 25-Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) along with measures of disease status (ataxia stage) and visual function (low- and high-contrast letter acuity scores). The relations of NEI-VFQ-25 scores to those for disease status and visual function were examined., Results: Scores for the NEI-VFQ-25 were lower in patients with FRDA (n = 99) compared with published disease-free controls, particularly reduced in a subgroup of FRDA patients with features of early onset, older age, and abnormal visual function., Conclusions: The NEI-VFQ-25 captures the subjective component of visual function in patients with FRDA.

Introduction: This study assessed the Health Related Quality of Life (HRQOL) of individuals with Friedreich Ataxia (FRDA) through responses to HRQOL questionnaires., Methods: The SF-36, a generic HRQOL instrument, and symptom specific scales examining vision, fatigue, pain and bladder function were administered to individuals with FRDA and analyzed by comparison with disease features. Multiple linear regression models were used to study independent effects of genetic severity and age. Assessments were performed at baseline then intermittently after that., Results: Subjects were on average young adults. For the SF36, the subscale with the lowest HRQOL score was the physical function scale, while the emotional well-being score was the highest. The physical function scale correlated with age of onset, duration, and subject age. In assessment of symptom specific scales, bladder control scores (BLCS) correlated with duration and age, while impact of visual impairment scores (IVIS) correlated with duration. In linear regression models, the BLCS, Pain Effect Score, and IVIS scores were predicted by age and GAA length; modified fatigue impact scale scores were predicted only by GAA length. Physical function and role limitation scores declined over time. No change was seen over time in other SF-36 subscores. Symptom specific scales also worsened over time, most notably the IVIS and BLCS., Conclusion: The SF-36 and symptom specific scales capture dysfunction in FRDA in a manner that reflects disease status. HRQOL dysfunction was greatest on physically related scales; such scales correlated with disease duration, indicating that they worsen with progressing disease., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Direct visualisation of cells for the purpose of studying their motility has typically required expensive microscopy equipment. However, recent advances in digital sensors mean that it is now possible to image cells for a fraction of the price of a standard microscope. Along with low-cost imaging there has also been a large increase in the availability of high quality, open-source analysis programs. In this study we describe the development and performance of an expandable cell motility system employing inexpensive, commercially available digital USB microscopes to image various cell types using time-lapse and perform tracking assays in proof-of-concept experiments. With this system we were able to measure and record three separate assays simultaneously on one personal computer using identical microscopes, and obtained tracking results comparable in quality to those from other studies that used standard, more expensive, equipment. The microscopes used in our system were capable of a maximum magnification of 413.6×. Although resolution was lower than that of a standard inverted microscope we found this difference to be indistinguishable at the magnification chosen for cell tracking experiments (206.8×). In preliminary cell culture experiments using our system, velocities (mean µm/min ± SE) of 0.81 ± 0.01 (Biomphalaria glabrata hemocytes on uncoated plates), 1.17 ± 0.004 (MDA-MB-231 breast cancer cells), 1.24 ± 0.006 (SC5 mouse Sertoli cells) and 2.21 ± 0.01 (B. glabrata hemocytes on Poly-L-Lysine coated plates), were measured and are consistent with previous reports. We believe that this system, coupled with open-source analysis software, demonstrates that higher throughput time-lapse imaging of cells for the purpose of studying motility can be an affordable option for all researchers.

This study identified Cryptosporidium genotypes in the Wissahickon watershed from May 2005 to April 2008. We analyzed 129 samples from Wissahickon Creek, 83 effluent samples from wastewater treatment plants (WWTPs), and 240 fecal droppings. Genotyping was based on the hypervariable region of the 18S rRNA gene. Oocysts were detected year-round, independent of wet weather events, in 22% of Wissahickon Creek samples, 5% of WWTP effluents, and 7% of fecal samples. Of the genotypes detected, 67% were human-infectious: 30% C. hominis or C. hominis-like, 12% C. parvum, 14% cervine genotype, 9% skunk genotype, and 1% chipmunk I genotype. Similar genotype profiles were detected in Wissahickon Creek each year, and human-infectious genotypes were detected year-round. Unusual genotypes detected in a deer (a C. hominis-like genotype) and geese (C. hominis-like genotypes, C. parvum, and muskrat genotype I) show that these animals are vectors of human-infectious genotypes in this watershed. Results suggest that deer, geese, and WWTPs are appropriate targets for source water protection in the Wissahickon watershed.

The purpose of this study was to compare the responses of isolated hearts of the diving muskrat with the nondividing guinea pig (GP) to determine the contribution of adenosine (ADO) to the profound bradycardia that was seen in isolated muskrat hearts during exposure to hypoxia. Muskrat hearts were more sensitive than GP hearts to the heart rate-lowering effects of exogenously applied ADO or a stable ADO analogue, (R)-N6-(phenylisopropyl)adenosine. The hearts of both species were unpaced, and the bradycardia appeared to be due to high degree of atrioventricular block. Radioligand binding with 8-cyclopentyl-1,3-[3H]dipropylxanthine to A1-ADO receptors was greater in cardiac membranes prepared from GP hearts than from muskrat hearts. Nucleoside transporter antagonist binding was also greater in GP hearts compared with muskrats. This was determined by membrane binding of [3H]-nitrobenzylthioinosine, an antagonist of nucleoside transport. Both muskrat and GP hearts responded to 30 min of hypoxic perfusion by releasing ADO into the coronary effluent; however, the muskrat hearts released approximately five times more than the GP hearts. When hearts were subjected to hypoxia in the presence of ADO deaminase, theophylline, or 8-(p-sulfophenyl)theophylline, the hypoxia-induced bradycardia was blocked in the GP hearts and either slightly reduced or not affected in muskrat hearts. In contrast to GP hearts, muskrat hearts release larger amounts of ADO during hypoxia and are more sensitive to the negative chronotropic effects of exogenously administered ADO; yet the hypoxia-induced bradycardia does not appear to be exclusively mediated by ADO in the muskrat as it is in the isolated GP heart.