Research Articles (Physiological Sciences)
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- ItemRehabilitation and primary care treatment guidelines, South Africa(World Health Organization, 2022-08) Conradie, Thandi; Charumbira, Maria; Bezuidenhout, Maryke; Leong, Trudy; Louw, QuinetteABSTRACT: The World Health Organization recognizes rehabilitation as an essential component of universal health coverage (UHC). In many countries, UHC builds on a standard benefits package of services that is informed by the country’s essential medicines list, standard treatment guidelines and primary health care essential laboratory list. In South Africa, primary health care is largely provided and managed by primary health-care nurses and medical officers in accordance with primary health care standard treatment guidelines. However, rehabilitation is mostly excluded from these guidelines. This paper describes the 10-year process that led to rehabilitation referral recommendations being considered for inclusion in South Africa’s primary health care standard treatment guidelines. There were five key events: (i) a breakthrough moment; (ii) producing a scientific evidence synthesis and formulating recommendations; (iii) presenting recommendations to the national essential medicines list committee; (iv) mapping rehabilitation recommendations onto relevant treatment guideline sections; and (v) submitting revised recommendations to the committee for final consideration. The main lesson learnt is that, by working together, rehabilitation professionals can be of sufficient number to make a difference, improve service delivery and increase referrals to rehabilitation from primary health care. A remaining challenge is the lack of a rehabilitation representative on the national essential medicines list committee, which could hamper understanding of rehabilitation and of the complexities of the supporting evidence.
- ItemSpermidine and rapamycin reveal distinct autophagy flux response and cargo receptor clearance profile(MDPI, 2021-01-07) De Wet, Sholto; Du Toit, Andre; Loos, BenAutophagy flux is the rate at which cytoplasmic components are degraded through the entire autophagy pathway and is often measured by monitoring the clearance rate of autophagosomes. The specific means by which autophagy targets specific cargo has recently gained major attention due to the role of autophagy in human pathologies, where specific proteinaceous cargo is insufficiently recruited to the autophagosome compartment, albeit functional autophagy activity. In this context, the dynamic interplay between receptor proteins such as p62/Sequestosome-1 and neighbour of BRCA1 gene 1 (NBR1) has gained attention. However, the extent of receptor protein recruitment and subsequent clearance alongside autophagosomes under different autophagy activities remains unclear. Here, we dissect the concentration-dependent and temporal impact of rapamycin and spermidine exposure on receptor recruitment, clearance and autophagosome turnover over time, employing micropatterning. Our results reveal a distinct autophagy activity response profile, where the extent of autophagosome and receptor co-localisation does not involve the total pool of either entities and does not operate in similar fashion. These results suggest that autophagosome turnover and specific cargo clearance are distinct entities with inherent properties, distinctively contributing towards total functional autophagy activity. These findings are of significance for future studies where disease specific protein aggregates require clearance to preserve cellular proteostasis and viability and highlight the need of discerning and better tuning autophagy machinery activity and cargo clearance.
- ItemSarcopenic obesity in Africa: a call for diagnostic methods and appropriate interventions(Frontiers Media S.A, 2021-04) Mendham, Amy E.; Lundin-Olsson, Lillemor; Goedecke, Julia H.; Micklesfield, Lisa K.; Christensen, Dirk L.; Gallagher, Iain J.; Myburgh, Kathryn H.; Odunitan-Wayas, Feyisayo A.; Lambert, Estelle V.; Kalula, Sebastiana; Hunter, Angus M.; Brooks, Naomi E.This perspective aims to highlight the lack of current knowledge on sarcopenic obesity in Africa and to call for diagnostic methods and appropriate interventions. Sarcopenic obesity has been defined as obesity that occurs in combination with low muscle mass and function, which is typically evident in older adults. However, there has been no clear consensus on population-specific diagnostic criterion, which includes both gold-standard measures that can be used in a more advanced health care system, and surrogate measures that can be used in low-income settings with limited resources and funding. Importantly, low and middle-income countries (LMICs) across Africa are in an ongoing state of economic and social transition, which has contributed to an increase in the aging population, alongside the added burden of poverty, obesity, and associated co-morbidities. It is anticipated that alongside the increased prevalence of obesity, these countries will further experience an increase in age-related musculoskeletal diseases such as sarcopenia. The developmental origins of health and disease (DOHaD) approach will allow clinicians and researchers to consider developmental trajectories, and the influence of the environment, for targeting high-risk individuals and communities for treatment and/or prevention-based interventions that are implemented throughout all stages of the life course. Once a valid and reliable diagnostic criterion is developed, we can firstly assess the prevalence and burden of sarcopenic obesity in LMICs in Africa, and secondly, develop appropriate and sustainable interventions that target improved dietary and physical activity behaviors throughout the life course.
- ItemTEG®, Microclot and Platelet Mapping for Guiding Early Management of Severe COVID-19 Coagulopathy(MDPI, 2021-11) Laubscher, Gert Jacobus; Lourens, Petrus Johannes; Venter, Chantelle; Kell, Douglas B; Pretorius, EtheresiaAn important component of severe COVID-19 disease is virus-induced endothelilitis. This leads to disruption of normal endothelial function, initiating a state of failing normal clotting physiology. Massively increased levels of von Willebrand Factor (VWF) lead to overwhelming platelet activation, as well as activation of the enzymatic (intrinsic) clotting pathway. In addition, there is an impaired fibrinolysis, caused by, amongst others, increased levels of alpha-(2) antiplasmin. The end result is hypercoagulation (proven by thromboelastography® (TEG®)) and reduced fibrinolysis, inevitably leading to a difficult-to-overcome hypercoagulated physiological state. Platelets in circulation also plays a significant role in clot formation, but they themselves may also drive hypercoagulation when they are overactivated due to the interactions of their receptors with the endothelium, immune cells or circulating inflammatory molecules. From the literature it is clear that the role of platelets in severely ill COVID-19 patients has been markedly underestimated or even ignored. We here highlight the value of early management of severe COVID-19 coagulopathy as guided by TEG®, microclot and platelet mapping. We also argue that the failure of clinical trials, where the efficacy of prophylactic versus therapeutic clexane (low molecular weight heparin (LMWH)) were not always successful, which may be because the significant role of platelet activation was not taken into account during the planning of the trial. We conclude that, because of the overwhelming alteration of clotting, the outcome of any trial evaluating an any single anticoagulant, including thrombolytic, would be negative. Here we suggest the use of the degree of platelet dysfunction and presence of microclots in circulation, together with TEG®, might be used as a guideline for disease severity. A multi-pronged approach, guided by TEG® and platelet mapping, would be required to maintain normal clotting physiology in severe COVID-19 disease.
- ItemErythrocyte, Platelet, Serum Ferritin, and P-Selectin Pathophysiology implicated in severe hypercoagulation and vascular complications in COVID-19(MDPI, 2020-11-03) Venter, Chantelle; Bezuidenhout, Johannes Andries; Laubscher, Gert Jacobus; Lourens, Petrus Johannes; Steenkamp, Janami; Kell, Douglas B.; Pretorius, EtheresiaProgressive respiratory failure is seen as a major cause of death in severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection. Relatively little is known about the associated morphologic and molecular changes in the circulation of these patients. In particular, platelet and erythrocyte pathology might result in severe vascular issues, and the manifestations may include thrombotic complications. These thrombotic pathologies may be both extrapulmonary and intrapulmonary and may be central to respiratory failure. Previously, we reported the presence of amyloid microclots in the circulation of patients with coronavirus disease 2019 (COVID-19). Here, we investigate the presence of related circulating biomarkers, including C-reactive protein (CRP), serum ferritin, and P-selectin. These biomarkers are well-known to interact with, and cause pathology to, platelets and erythrocytes. We also study the structure of platelets and erythrocytes using fluorescence microscopy (using the markers PAC-1 and CD62PE) and scanning electron microscopy. Thromboelastography and viscometry were also used to study coagulation parameters and plasma viscosity. We conclude that structural pathologies found in platelets and erythrocytes, together with spontaneously formed amyloid microclots, may be central to vascular changes observed during COVID-19 progression, including thrombotic microangiopathy, diffuse intravascular coagulation, and large-vessel thrombosis, as well as ground-glass opacities in the lungs. Consequently, this clinical snapshot of COVID-19 strongly suggests that it is also a true vascular disease and considering it as such should form an essential part of a clinical treatment regime.