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Abstract Background Amyotrophic lateral sclerosis (ALS) is a devastating and incurable neurodegenerative disease. Accumulating evidence strongly suggests that intrinsic muscle defects exist and contribute to disease progression, including imbalances in whole-body metabolic homeostasis. We have previously reported that tumour necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) and fibroblast growth factor inducible 14 (Fn14) are significantly upregulated in skeletal muscle of the SOD1 G93A ALS mouse model. While antagonising TWEAK did not impact survival, we did observe positive effects in skeletal muscle. Given that Fn14 has been proposed as the main effector of the TWEAK/Fn14 activity and that Fn14 can act independently from TWEAK in muscle, we suggest that manipulating Fn14 instead of TWEAK in the SOD1 G93A ALS mice could lead to differential and potentially improved benefits. Methods We thus investigated the contribution of Fn14 to disease phenotypes in the SOD1 G93A ALS mice. To do so, Fn14 knockout mice (Fn14 −/− ) were crossed onto the SOD1 G93A background to generate SOD1 G93A ;Fn14 −/− mice. Investigations were performed on both unexercised and exercised (rotarod and/or grid test) animals (wild type (WT), Fn14 −/−, SOD1 G93A and SOD1 G93A ;Fn14 −/− ). Results Here, we firstly confirm that the TWEAK/Fn14 pathway is dysregulated in skeletal muscle of SOD1 G93A mice. We then show that Fn14-depleted SOD1 G93A mice display increased lifespan, myofiber size, neuromuscular junction endplate area as well as altered expression of known molecular effectors of the TWEAK/Fn14 pathway, without an impact on motor function. Importantly, we also observe a complex interaction between exercise (rotarod and grid test), genotype, disease state and sex that influences the overall effects of Fn14 deletion on survival, expression of known molecular effectors of the TWEAK/Fn14 pathway, expression of myosin heavy chain isoforms and myofiber size. Conclusions Our study provides further insights on the different roles of the TWEAK/Fn14 pathway in pathological skeletal muscle and how they can be influenced by age, disease, sex and exercise. This is particularly relevant in the ALS field, where combinatorial therapies that include exercise regimens are currently being explored. As such, a better understanding and consideration of the interactions between treatments, muscle metabolism, sex and exercise will be of importance in future studies.

Abstract Introduction Posterior tibial nerve (PTN) cross‐sectional area (CSA) reference values for the diagnosis of tarsal tunnel syndrome (TTS) using ultrasound imaging exist in several countries but not in South Africa (SA). Therefore, the objective was to measure the CSA reference values for PTN in SA. Methods Ultrasound CSA measurements of PTN in both ankles on 112 participants were performed, the mean measurement was recorded, and the effect of race, age, gender, and body mass index (BMI) were recorded. Results In this study, the primary variables age and BMI affect the CSA measurement of the PTN. A positive correlation was found between PTN asymptomatic size and age (r = 0.196, P

Abstract While first-generation, spike (S)-based COVID-19 vaccines were effective against early SARS-CoV-2 strains, the rapid evolution of novel Omicron subvariants have substantially reduced vaccine efficacy. As such, broadly protective vaccines against SARS-CoV-2 are needed to prevent future viral emergence. In addition, it remains less clear whether peripheral immunization, especially with mRNA vaccines, elicits effective respiratory immunity. Our group has developed a nucleoside-modified mRNA vaccine expressing the nucleocapsid (N) protein of the ancestral SARS-CoV-2 virus and has tested its use in combination with the S-based mRNA vaccine (mRNA-S). In this study, we examined efficacy of mRNA-N alone or in combination with mRNA-S (mRNA-S+N) against more immune evasive Omicron variants in hamsters. Our data show that mRNA-N alone induces a modest but significant protection against BA.5 and that dual mRNA-S+N vaccination confers complete protection against both BA.5 and BQ.1, preventing detection of virus in the hamster lungs. Analysis of respiratory immune response in mice shows that intramuscular mRNA-S+N immunization effectively induces respiratory S- and N-specific T cell responses in the lungs and in bronchoalveolar lavage (BAL), as well as antigen-specific binding IgG in BAL. Together, our data further support mRNA-S+N as a potential pan-COVID-19 vaccine for broad protection against current and emerging SARS-CoV-2 variants.

While the exercise-induced responses of circulated biomarkers related to inflammation and brain health are well documented in humans, little is known about the effect of menopausal status on these responses. This study compared the responses of inflammatory cytokines and brain-derived neurotrophic factor (BDNF) to high-intensity exercise between pre- and postmenopausal middle-aged females. Eight premenopausal (44 ± 3 years) and seven postmenopausal (57 ± 2 years) females performed a high-intensity interval training (HIIT) session consisting of 10 × 1 min running intervals (90% maximum heart rate) separated by 1 min passive recovery intervals. Blood samples were collected at baseline (fasted), pre-exercise (postprandial), and at 0, 30, and 90 min post-HIIT and analyzed for interleukin (IL-6) and 10 (IL-10), tumour necrosis factor-alpha (TNF-α), and BDNF. IL-6 significantly increased from pre-exercise to 0 min post-HIIT in postmenopausal (+40%, p = 0.01) and to 30 min post-HIIT in premenopausal females (+60%, p = 0.02). IL-6 remained elevated at 90 min post-HIIT in premenopausal (+104%, p = 0.05) and to a higher degree in postmenopausal females (+385%, p < 0.001). IL-10 showed no response. TNF-α increased from pre- to 0 min post-HIIT (+10%, p = 0.05), then decreased to below pre-exercise at 30 min (−10%, p = 0.02) and 90 min (−5%, p = 0.04) in both groups. BDNF increased immediately post-HIIT in premenopausal (+60%, p < 0.001) but not postmenopausal females. The differences in IL-6 and BDNF responses to HIIT between pre- and postmenopausal females provide evidence of the role of female reproductive hormones in the regulation of these exercise-induced responses.

Abstract Pharmaceutically active compounds have been considered contaminants of emerging concern, in response to evidence that these substances may adversely affect non-target organisms. The pharmaceutical metformin is the most commonly prescribed anti-diabetes medicine throughout the world. Metformin has been detected in numerous freshwater systems as well as in seawater at a number of sites around the world over the last few years, but has never been reported in the Indonesian capital city Jakarta. Several recent studies have highlighted various ecotoxicological effects of this medicine on aquatic organisms. Here we report the first evidence of metformin’s presence in Jakarta waters. Samples from the Angke river, one of the main rivers in Jakarta, were collected from six sites. Metformin was detected at three sites in concentrations ranging from 27 ng/L to 414 ng/L. Metformin is one of the most detected APIs (active pharmaceutical ingredients) in aquatic environments worldwide, and there is increasing concern regarding its impact on the health of wildlife and humans. However, this is the first report of metformin contamination in Jakarta waters, adding to the evidence of potentially increased pollution with pharmaceuticals, as noted in our previous studies. With no natural degradation processes, these chemical compounds can be easily reintroduced to the food chain and impact human health.

Background: Group work is employed in higher education institutions to foster communication, collaborative learning, leadership qualities and teamwork skills. The rationale behind group work as a learning strategy is to ensure that graduates are equipped with teamwork skills. Aim: The aim of this study was to establish whether the final-year radiography students of the National Diploma curriculum in three universities in South Africa were exposed to effective group work. Setting: The study was conducted in three universities in South Africa, all of which offer diagnostic radiography programmes. Methods: This study used a non-experimental descriptive design to collect data. A purposive sampling technique was used to select participants. This was an attempt to conduct a census on 167 students, out of which 124 students responded to the questionnaire, giving a response rate of 74.25%. Results: The findings show that the majority (n = 81; 66.9%) of students did not enjoy group work, as 101 (81.5%) of them preferred less group projects. The results further demonstrated that participants rated factors such as co-operation, leadership, choice, diversity and effectiveness of group work neutral on the Likert scale. Conclusion: The study results imply that factors that contribute towards the effectiveness of group work should be incorporated into group activities in order for student radiographers to be exposed to effective group work. The gaps identified in this study indicate the need for a follow-up study within the current 4-year bachelor’s degree in radiography. Contribution: Identification of a gap in radiography education, which group work needs to be facilitated effectively.

Abstract Objective To investigate the effects of moderate‐intensity aerobic exercise on appetite control parameters, appetite perceptions, and energy intake in sedentary males with obesity. Design Eleven males with obesity (body fat percentage 36.5 ± 2.5%, body mass index 35.3 ± 4.2 kg/m2, V̇O2peak 29 ± 3.1 mL·kg−1·min−1) completed two experimental sessions: (1) no exercise (CTRL) and (2) 60 min of moderate‐intensity cycling exercise at 60% V̇O2peak (MICT) in a crossover design. Blood analysis included growth differentiation factor 15 (GDF‐15), total ghrelin, peptide tyrosine tyrosine3–36 (PYY3–36), total glucagon‐like peptide‐1 (GLP‐1), insulin, and glucose, as well as subjective appetite perceptions were measured in specific intervals. A standard breakfast at 0 h and an ad libitum meal postexercise was provided. Result GDF‐15 (95% confidence interval [CI]: [2.48–27.28] ng/L, p = 0.021) increased immediately following MICT compared to CTRL. However, there were no differences for PYY3–36 (p = 0.480, ηp2=0.025), total ghrelin (p = 0.646, ηp2=0.011), and total GLP‐1 (p = 0.451, ηp2=0.029) between sessions. Appetite perceptions (95% CI: [(−20.38)–(−6.16)] mm, p = 0.001) were suppressed following MICT though energy intake was not different between the sessions (95% CI: [(−1904.9)–928.1] kJ, p = 0.480). Conclusion Sixty minutes of MICT increased GDF‐15 while suppressing appetite perceptions in individuals with obesity. There was no energy compensation postexercise.

Abstract Differentiation of adipose progenitor cells into mature adipocytes entails a dramatic reorganization of the cellular architecture to accommodate lipid storage into cytoplasmic lipid droplets. Lipid droplets occupy most of the adipocyte volume, compressing the nucleus beneath the plasma membrane. How this cellular remodeling affects sub-nuclear structure, including size and number of nucleoli, remains unclear. We describe the morphological remodeling of the nucleus and the nucleolus during in vitro adipogenic differentiation of primary human adipose stem cells. We find that cell cycle arrest elicits a remodeling of nucleolar structure which correlates with a decrease in protein synthesis. Strikingly, triggering cytoskeletal rearrangements mimics the nucleolar remodeling observed during adipogenesis. Our results point to nucleolar remodeling as an active, mechano-regulated mechanism during adipogenic differentiation and demonstrate a key role of the actin cytoskeleton in defining nuclear and nucleolar architecture in differentiating human adipose stem cells.

Abstract Introduction The study explored and described the professional identity of diagnostic radiographers in Johannesburg, Gauteng, South Africa. Methods The methodology employed for the study was qualitative, exploratory and descriptive design. Face‐to‐face interviews were conducted with thirteen diagnostic radiographers from private, public practices and individually owned practices. Semi‐structured interviews were conducted, and the responses underwent thematic analysis and used Braun and Clarke's six steps for analysing qualitative data. Results The thematic analysis revealed three themes and six categories. The three themes identified were: perceptions of identity, environment influences and organisational institutions. Conclusion This study provided an insight into the current perspectives of the professional identity of diagnostic radiographers in Johannesburg, South Africa, which reflected a positive professional identity. The three themes identified could inform guidelines for education in diagnostic radiographers' professional identity in the future.

Background: Management of radiography departments requires skilled and competent managers. This task becomes complex if there is no management development and collaborative performance monitoring. Aim: The study aimed to explore and describe the radiography managers’ perceptions regarding management training and skills required. Setting: The research was conducted in public health institutions of Gauteng, South Africa. Methods: Qualitative, exploratory and descriptive approach was adopted, and a purposive sampling method was used to select twenty-three (23) managers from the radiography departments; however, data saturation guided the sample size. Data were collected through online focus group discussions (FGDs). Ethical approval was obtained through Departmental Research Committee (DRC) of Medical Imaging and Radiation Sciences (MIRS) department, Higher Degrees Committee (HDC), Research Ethics Committee and Gauteng Department of Health Research Committees. Data trustworthiness was obtained through member checking, data verification and an independent coder to verify the accuracy of the data. Thematic data analysis method was used to analyse the data. Results: Five themes emerged from the thematic analysis and centred on: difficulties in transitioning into management, lack of management support, the need for postgraduate management qualification, coaching and mentoring and required skills for radiography managers. Conclusion: Public health institutions continuously face transitions in service delivery frameworks. This requires competent and skilled radiography managers to survive in this environment. The study revealed that new managers experience difficulties and require management support to succeed in their roles. Contribution: Awareness of managers developmental needs relative to the real-life dynamics of radiography management in Gauteng public health environment.

Abstract The first systematic reviews of the effects of exercise on appetite‐regulation and energy intake demonstrated changes in appetite‐regulating hormones consistent with appetite suppression and decreases in subsequent relative energy intake over a decade ago. More recently, an intensity‐dependent effect and several potential mechanisms were proposed, and this review aims to highlight advances in this field. While exercise‐induced appetite suppression clearly involves acylated ghrelin, glucagon‐like peptide‐1 may also be involved, though recent evidence suggests peptide tyrosine tyrosine may not be relevant. Changes in subjective appetite perceptions and energy intake continue to be equivocal, though these results are likely due to small sample sizes and methodological inconsistencies. Of the proposed mechanisms responsible for exercise‐induced appetite suppression, lactate has garnered the most support through in vitro and in vivo rodent studies as well as a growing amount of work in humans. Other potential modulators of exercise‐induced appetite suppression may include sex hormones, growth‐differentiation factor 15, Lac‐Phe, brain‐derived neurotrophic factor, and asprosin. Research should focus on the mechanisms responsible for the changes and consider these other modulators (i.e., myokines/exerkines) of appetite to improve our understanding of the role of exercise on appetite regulation.