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Abstract Background It is unknown whether high-intensity interval exercise (HIIE) may potentiate or attenuate the cardiotoxic effect of chemotherapy agents such as doxorubicin (DOX) when performed shortly after treatment. The study aimed to investigate the effect of acute HIIE on cardiac function and structure performed either 1, 2 or 3 days after DOX injection in an animal model. Methods Female C57bl/6 mice (n = 28), 70 days old, received a bolus 20 mg/kg intravenous tail vein DOX injection. Three exercise groups performed 1 HIIE session (16 sets of 1 min at 85–90% of peak running speed) at 1 (n = 7), 2 (n = 7), and 3 days (n = 8) following the DOX injection. A sedentary (SED) group of mice (n = 6) did not exercise. Animals underwent echocardiography under light anesthesia (isoflurane 0.5-1%) before and 7 days after the DOX injection. Animals were sacrificed on day 9 and hearts were collected for morphometric and histological analysis. Results Animals exercising on day 3 had the smallest pre-post reduction in left ventricular fractional shortening (LVFS) (MΔ= -1.7 ± 3.3; p = 0.406) and the SED group had the largest reduction (MΔ=-6.8 ± 7.5; p = 0.009). After reclassification of animals according to their exercise compliance (performing > 8/16 of high-intensity bouts), LVFS in compliant mice was unchanged over time (LVFS MΔ= -1.3 ± 5.6; p = 0.396) while non-compliant animals had a LVFS reduction similar to sedentary animals. There were no significant differences in myocardial histology between groups. Conclusions In this pilot murine study, one single HIIE session did not exacerbate acute doxorubicin-induced cardiotoxicity. The timing of the HIIE session following DOX injection and the level of compliance to exercise could influence the negative impact of DOX on cardiac function.

A quarter of a century after South Africa's transition to democracy, the rhetoric of 'transformation' remains firmly ingrained in its higher education policy and discourse. In many of the reviews, reports, proposals, and frameworks on the transformation of the South African university system, one thing stands out: an oversupply of rhetoric and a dearth of empirical data. This article is a direct response to how infrequently data has been used and seeks to reveal the actual quantum of change, albeit with a focus on an admittedly singular element on the transformation spectrum but one which nevertheless preoccupies South Africans: equity (or race). The evidence presented in the paper shows that the absence of a clear articulation of transformation, accompanied by a lack of indicators and targets to track progress over time, hinders the progression of the discourse to equally important dimensions of performance such as efficiency, success and productivity--all of which are critical in determining the university's role in national development. The paper goes on to show that based on the data available, the public university system in South Africa is "transforming" given the increases over time in the number of black students and staff. However, without a clearly articulated idea of what constitutes change, one cannot claim a "transformed" system, and the political narrative of no transformation is likely to prevail.

Abstract Background Cancer patients at advanced stages experience a severe depletion of skeletal muscle compartment together with a decrease in muscle function, known as cancer cachexia. Cachexia contributes to reducing quality of life, treatment efficiency, and lifespan of cancer patients. However, the systemic nature of the syndrome is poorly documented. Here, we hypothesize that glucocorticoids would be important systemic mediators of cancer cachexia. Methods To explore the role of glucocorticoids during cancer cachexia, biomolecular analyses were performed on several tissues (adrenal glands, blood, hypothalamus, liver, and skeletal muscle) collected from ApcMin/+ male mice, a mouse model of intestine and colon cancer, aged of 13 and 23 weeks, and compared with wild type age‐matched C57BL/6J littermates. Results Twenty‐three‐week‐old Apc mice recapitulated important features of cancer cachexia including body weight loss (−16%, P

A quarter of a century after South Africa's transition to democracy, the rhetoric of 'transformation' remains firmly ingrained in its higher education policy and discourse. In many of the reviews, reports, proposals, and frameworks on the transformation of the South African university system, one thing stands out: an oversupply of rhetoric and a dearth of empirical data. This article is a direct response to how infrequently data has been used and seeks to reveal the actual quantum of change, albeit with a focus on an admittedly singular element on the transformation spectrum but one which nevertheless preoccupies South Africans: equity (or race). The evidence presented in the paper shows that the absence of a clear articulation of transformation, accompanied by a lack of indicators and targets to track progress over time, hinders the progression of the discourse to equally important dimensions of performance such as efficiency, success and productivity-all of which are critical in determining the university's role in national development. The paper goes on to show that based on the data available, the public university system in South Africa is transforming given the increases over time in the number of black students and staff. However, without a clearly articulated idea of what constitutes change, one cannot claim a transformed system, and the political narrative of no transformation is likely to prevail., Author(s): François B. Van Schalkwyk [sup.1] , Milandré H. van Lill [sup.1] , Nico Cloete [sup.1] , Tracy G. Bailey [sup.1] Author Affiliations: (1) grid.11956.3a, 0000 0001 2214 904X, DSI-NRF [...]

Purpose: Repeated-sprint training in hypoxia (RSH) leads to great improvements in anaerobic performance. However, there is no consensus about the optimal level of hypoxia that should be used during training to maximize subsequent performances. This study aimed to establish whether such an optimal altitude can be determined and whether pulse oxygen saturation during RSH is correlated with training-induced improvement in performance.Methods: Peak and mean power outputs of healthy young males [age (mean ± SD) 21.7 ± 1.4 years] were measured during a Wingate (30 s) and a repeated-sprint ability (RSA; 10 x 6-s sprint with 24-s recovery) test before and after RSH. Participants performed six cycling sessions comprising three sets of 8 x 6-s sprint with 24-s recovery in normobaric hypoxia at a simulated altitude of either 1,500 m, 2,100 m, or 3,200 m (n = 7 per group). Heart rate variability was assessed at rest and during recovery from Wingate test before and after RSH.Results: The subjective rating of perceived exertion and the relative exercise intensity during training sessions did not differ between the three groups, contrary to pulse oxygen saturation (p < 0.001 between each group). Mean and peak power outputs were significantly increased in all groups after training, except for the mean power in the RSA test for the 3200 m group. Change in mean power on RSA test (+8.1 ± 6.6%) was the only performance parameter significantly correlated with pulse oxygen saturation during hypoxic training (p < 0.05, r = 0.44). The increase in LnRMSSD during recovery from the Wingate test was enhanced after training in the 1,500 m (+22%) but not in the two other groups (≈– 6%). Moreover, the increase in resting heart rate with standing after training was negatively correlated with SpO2 (p < 0.01, r =–0.63) suggesting that hypoxemia level during training differentially altered autonomic nervous system activity.Conclusion: These data indicate that RSH performed as early as 1,500 m of altitude is effective in improving anaerobic performance in moderately trained subjects without strong association with pulse oxygen saturation monitoring during training.

Valvular calcifications (VCs) are one of the major cardiovascular complications in patients on chronic hemodialysis (HD) due to its prevalence and predictive morbidity and mortality. The current study assessed the prevalence, location, and risk factors of VC among chronic HD Congolese patients in Kinshasa. This observational study involved three HD centers in Kinshasa between March and August 2016. Consecutive consenting adults on maintenance HD for at least six months were recruited. VCs were defined as a luminous echo on one or more cusps of the aortic or mitral valve. Risk factors of VC were determined by multivariate analysis. Sixty patients (mean age: 52.5 ± 15.9 years) were enrolled. The mean serum calcium and phosphorus were7.9 ± 1.3 mg/dL and 5.7 ± 1.7 mg/dL, respectively. VCs were encountered in 38% of the whole group in aortic and mitral valvular location in 64% and 23%, respectively. Hypertension, age >60 years, tobacco use, and hyperphosphatemia were independently associated with VC. Despite a young age of patients, VCs were a common finding and associated with both traditional and chronic kidney disease-specific risk factors.

The production and reproduction of knowledge are important components of national development. As student mobility increases, globally and within Africa, so does the national diversity of students as they seek to further their postgraduate studies at the limited number of research universities in Africa. Knowledge migration is inevitably a relationship between nation states because migration is driven by push factors (such as the socio-economic conditions and opportunities) in the country of origin as well as by pull factors (such as the rules and incentives for entry, participation in postgraduate education and post-study residency), which are prerogatives of the host nation. In other words, migration and development must be understood in comparative terms. The brain drain perspective on migration and development takes mainly the perspective of the origin country into consideration. Migration and the loss of high-level skills are seen as detrimental to the development prospects of the country of origin. The brain circulation perspective moves the discussion forward by suggesting that there are residual returns to the country of origin. However, relatively little attention has been given to the impact of knowledge migrants on the host nation when the host is facing its own post-colonial development challenges. This is the dilemma facing South Africa as a hub for doctoral students from the rest of Africa: attracting top doctoral students from the rest of the continent to contribute to the country’s knowledge capacity but at the expense of developing local talent, thereby setting up a complex tension between underdevelopment and development. Here we establish whether South Africa is maintaining its position as a PhD hub on the African continent and explore the extent to which the brain circulation argument holds up in the African context. We suggest that, given the current policy environment in South Africa, brain circuity is a more likely outcome, where brain circuity describes the flow of knowledge characterised by indirection and undesirable intricacy. Significance: • In the case of South Africa as a destination for doctoral students from the rest of Africa, neither the brain drain nor the brain circulation theories of student mobility hold; rather, students are confronted with an overly complex set of conditions resulting in brain circuity. • Despite the continued attractiveness of South Africa as a destination for doctoral students, the tension between equity and development remains unresolved at the policy level, potentially undermining the circulation of knowledge for the benefit of all African countries.

The aim of this review was to summarise the available HBM data in DRC in order to provide recommendations for developing the HBM field. We performed a systematic search of PubMed/MedLine, EMBASE, and ISI Web of Science for papers on exposure levels to chemicals in DR C (2009-2019). A total of 12 papers were found: 9 in Kinshasa (75.0%) and 3 in Katanga (25.0%). Globally, the results reveal concern about exposure levels to environmental chemicals, mostly heavy metals. Some studies connected HBM data to negative health effects (preeclampsia, birth defects, children's temperament difficulties, holoprosencephaly) demonstrating the importance of regulation in occupational and environmental settings. The recommendations of this review include expanding HBM studies as well as the number of environmental chemicals; and establishment of a national HBM laboratory for developing and/or enhancing the capacity of DRC to undertake a national policy-related HBM.

Introduction: Apolipoprotein-L1 (APOL1) risk variants G1 and G2 increase the risk of chronic kidney disease (CKD), including HIV-related CKD, among African Americans. However, such data from populations living in Africa, especially children, remain limited. Our research aimed to determine the prevalence of APOL1 risk variants and to assess the association between these variants and early-stage CKD in the general pediatric population and HIV-infected children. Methods: In a cross-sectional study, we enrolled 412 children from the general population and 401 HIV-infected children in Kinshasa, Democratic Republic of Congo (DRC). APOL1 high-risk genotype (HRG) was defined by the presence of 2 risk variants (G1/G1, G2/G2, or G1/G2), and low-risk genotype (LRG) by the presence of 0 or 1 risk variants. The main outcome was elevated albuminuria, defined as a urinary albumin/creatinine ratio ≥30 mg/g. Results: APOL1 sequence analysis revealed that in the general population, 29 of 412 participants (7.0%) carried HRG, 84 of 412 (20.4%) carried the G1/G0 genotype, and 61 of 412 (14.8%) carried the G2/G0 genotype. In HIV-infected children, 23 of 401 (5.7%) carried HRG, and the same trend as in the general population was observed in regard to the prevalence of LRG. Univariate analysis showed that in the general population, 5 of 29 participants (17.2%) carrying HRG had elevated albuminuria, compared with 35 of 383 (9.0%) with LRG (odds ratio [OR] 2.1, 95% confidence interval [CI] 0.6–6.0; P = 0.13). In HIV-infected children, participants who carried APOL1 HRG had almost 22-fold increased odds of albuminuria compared to those with LRG. Conclusion: The APOL1 risk variants are prevalent in children living in DRC. HRG carriers have increased odds of early kidney disease, and infection with HIV dramatically increases this probability. Keywords: Africa, APOL1, general population, HIV, kidney damage

Although the lungs remain the main target of SARS-CoV-2, other organs, such as kidneys, can be affected, which has a negative impact on the outcomes of COVID-19 patients. Although previous studies of kidney disease in COVID-19 reported mainly SARS-CoV-2-induced tubular and interstitial injury, there is growing evidence coming out of Africa of glomerular involvement, especially collapsing glomerulopathy seen particularly in people of African descent. We report a case of collapsing glomerulopathy revealed by acute kidney injury and a new onset of full blown nephrotic syndrome in a black Congolese patient coinfected with COVID-19 and malaria.

Abstract Background Skeletal muscle atrophy is a common feature of numerous chronic pathologies and is correlated with patient mortality. The REDD1 protein is currently recognized as a negative regulator of muscle mass through inhibition of the Akt/mTORC1 signaling pathway. REDD1 expression is notably induced following glucocorticoid secretion, which is a component of energy stress responses. Results Unexpectedly, we show here that REDD1 instead limits muscle loss during energetic stresses such as hypoxia and fasting by reducing glycogen depletion and AMPK activation. Indeed, we demonstrate that REDD1 is required to decrease O2 and ATP consumption in skeletal muscle via reduction of the extent of mitochondrial-associated endoplasmic reticulum membranes (MAMs), a central hub connecting energy production by mitochondria and anabolic processes. In fact, REDD1 inhibits ATP-demanding processes such as glycogen storage and protein synthesis through disruption of the Akt/Hexokinase II and PRAS40/mTORC1 signaling pathways in MAMs. Our results uncover a new REDD1-dependent mechanism coupling mitochondrial respiration and anabolic processes during hypoxia, fasting, and exercise. Conclusions Therefore, REDD1 is a crucial negative regulator of energy expenditure that is necessary for muscle adaptation during energetic stresses. This present study could shed new light on the role of REDD1 in several pathologies associated with energetic metabolism alteration, such as cancer, diabetes, and Parkinson’s disease.