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Covid-19 demography in France and South Africa: a comparative study of morbidity and mortality in 2020–2022
(Public Library of Science, 2024) Garenne, Michel; Stiegler, Nancy
Background Covid-19 epidemics raged around the world in years 2020–2022. The dynamics of the epidemics and their mortality varied by country depending on prevention, treatments, vaccination and health status of the population. Objective The study compares Covid-19 morbidity and mortality in South-Africa and in France, two countries with similar population size and with reliable reporting systems, in order to better understand the dynamics and impacts of the epidemics and the effects of health policies and programs. Data and methods Data on cases, deaths, hospitalizations, vaccinations were drawn from national statistics. Published data on cases and deaths were corrected for undercount. Results Results show a different epidemiology in the two countries in the first three years of the epidemic (2020–2022). Incidence was higher in South Africa, and some 44% more people were infected by December 2022 than in France. Mortality and case-fatality were also higher in South Africa despite a favourable age structure. The age pattern of mortality showed higher values in South Africa among the young adults. Young women appeared somewhat disadvantaged in South Africa. Lastly, vaccination appeared to have had no effect on incidence, but a large effect on case-fatality in France. Conclusions Despite about the same population size and the same crude death rate at baseline, South Africa exhibited more cases and more deaths from Covid-19 over the 2020–2022 period. Prevention strategies (lockdown and vaccination) appear to have had large impacts on morbidity and mortality.
Detection and genome sequencing of lumpy skin disease viruses in wildlife game species in South Africa
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) van Schalkwyk, Antoinette; Kara, Pravesh; Last, Robert
Lumpy skin disease virus (LSDV) has recently undergone rapid spread, now being reported from more than 80 countries, affecting predominantly cattle and to a lesser extent, water buffalo. This poxvirus was previously considered to be highly host-range restricted. However, there is an increasing number of published reports on the detection of the virus from different game animal species. The virus has not only been shown to infect a wide range of game species under experimental conditions, but has also been naturally detected in oryx, giraffe, camels and gazelle. In addition, clinical lumpy skin disease has previously been described in springbok (Antidorcas marsupialis), an African antelope species, in South Africa. This report describes the characterization of lumpy skin disease virus belonging to cluster 1.2, from field samples from springbok, impala (Aepyceros melampus) and a giraffe (Giraffa camelopardalis) in South Africa using PCR, Sanger and whole genome sequencing. Most of these samples were submitted from wild animals in nature reserves or game parks, indicating that the disease is not restricted to captive-bred animals on game farms or zoological gardens. The potential role of wildlife species in the transmission and maintenance of LSDV is further discussed and requires continuing investigation, as the virus and disease may pose a serious threat to endangered species.
Antibacterial activity and cytotoxicity screening of acyldepsipeptide-1 analogues conjugated to silver/indium/sulphide quantum dots
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Cobongela, Sinazo; Makatini, Maya; Sibuyi, Nicole
The continuous rise in bacterial infections and antibiotic resistance is the driving force behind the search for new antibacterial agents with novel modes of action. Antimicrobial peptides (AMPs) have recently gained attention as promising antibiotic agents with the potential to treat drug-resistant infections. Several AMPs have shown a lower propensity towards developing resistance compared to conventional antibiotics. However, these peptides, especially acyldepsipeptides (ADEPs) present with unfavorable pharmacokinetic properties, such as high toxicity and low bioavailability. Different ways to improve these peptides to be drug-like molecules have been explored, and these include using biocompatible nano-carriers. ADEP1 analogues (SC005-8) conjugated to gelatin-capped Silver/Indium/Sulfide (AgInS2) quantum dots (QDs) improved the antibacterial activity against Gram-negative (Escherichia coli and Pseudomonas aeruginosa), and Gram-positive (Bacillus subtilis, Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus) bacteria. The ADEP1 analogues exhibited minimum inhibition concentrations (MIC) between 63 and 500 µM, and minimum bactericidal concentrations (MBC) values between 125 and 750 µM. The AgInS2-ADEP1 analogue conjugates showed enhanced antibacterial activity as evident from the MIC and MBC values, i.e., 1.6–25 µM and 6.3–100 µM, respectively. The AgInS2-ADEP1 analogue conjugates were non-toxic against HEK-293 cells at concentrations that showed antibacterial activity. The findings reported herein could be helpful in the development of antibacterial treatment strategies.
Crisis management competencies: a university stakeholder perspective
(John Wiley and Sons Inc, 2024) Pharaoh, Courtley D.; Visser, Dirk
South African universities faced an unforeseen crisis in the form of the #FeesMustFall (#FMF) movement. The executive management of the affected universities was criticized for how the crisis was handled. Due to the significant cost (over R1 billion) to the higher education sector, not just in fiscal losses, but the loss of life, the investment into crisis management would be justified. Crisis management is a business action that includes planning and organising to prepare for and to respond to threats to business activities. Reviewing the literature identified a void regarding the crisis management competencies needed by the Executive Management as perceived by stakeholders. This exploratory study made use of a mixed methodology research design. A self-administered questionnaire incorporating open-ended questions was used to identify and explore the competencies perceived by the stakeholders as important during times of crisis. Simple descriptive statistics were used to identify the top management competencies needed in a time of crisis as perceived by the stakeholders. This was compared with the findings in the literature. The study identified 10 management competencies perceived by stakeholders of which eight competencies are consistent with crisis management competencies found in the literature.
Heterocyclic (pyrazine)carboxamide Ru(II) complexes: structural, experimental and theoretical studies of interactions with biomolecules and cytotoxicity†
(Royal Society of Chemistry, 2024) Tsaulwayo, Nokwanda; Sibuyi, Nicole Remaliah Samantha; Meyer, Mervin
Treatments of N-(1H-benzo[d]imidazol-2-yl)pyrazine-2-carboxamide (HL1) and N-(benzo[d]thiazol-2-yl)pyrazine-2-carboxamide carboxamide ligands (HL2) with [Ru(p-cymene)Cl2]2 and [Ru(PPh3)3Cl2] precursors afforded the respective Ru(ii) complexes [Ru(L1)(p-cymene)Cl] (Ru1), [Ru(L2)(p-cymene)Cl] (Ru2), [Ru(L1)(PPh3)2Cl] (Ru3), and [Ru(L2)(PPh3)2Cl] (Ru4). These complexes were characterized by NMR, FT-IR spectroscopies, mass spectrometry, elemental analyses, and crystal X-ray crystallography for Ru2. The molecular structure of complex Ru2 contains one mono-anionic bidentate bound ligand and display pseudo-octahedral piano stool geometry around the Ru(ii) atom. The interactions with calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) were investigated by spectroscopic techniques. The experimental binding studies suggest that complexes Ru1-Ru4 interact with DNA, primarily through minor groove binding, as supported by molecular docking results. Additionally, these complexes exhibit strong quenching of the fluorescence of tryptophan residues in BSA, displaying static quenching. The in vitro cytotoxicity studies of compounds Ru1-Ru4 were assessed in cancer cell lines (A549, PC-3, HT-29, Caco-2, and HeLa), as well as a non-cancer line (KMST-6). Compounds Ru1 and Ru2 exhibited superior cytotoxicity compared to Ru3 and Ru4.