Magister Scientiae - MSc (Medical BioSciences)

Permanent URI for this collectionhttps://hdl.handle.net/10566/17104

Browse

Now showing 1 - 20 of 178

Encapsulation and controlled release of halogenated natural products in nanoformulations for enhanced stability and biological activity
(University of the Western Cape, 2026) Mudanabula Ritshidze; D. Beukes; E. Antunes
Marine seaweeds, or macroalgae, represent a prolific source of natural products with promising antibacterial and antifungal properties. These organisms produce a wide array of secondary metabolites, including halogenated compounds, which exhibit potent activity against drug-resistant bacterial and fungal strains. The therapeutic development of these compounds is hindered by challenges related to their lipophilicity, poor solubility and limited stability under physiological conditions. However, such challenges can be addressed through advanced formulation strategies such as nanoencapsulation. Therefore, this study aims to address these limitations by developing solid lipid nanoparticle (SLNs) based formulations for halogenated compounds to enhance their solubility, stability and biological efficacy. Two identified monoterpenes (1 and 2) were isolated and characterized using standard chromatographic and spectroscopic techniques. Structural assignment was established using standard TOCSY, 1D and 2D NMR experiments. SLNs formulations were prepared by hot homogenization followed by ultra sound technique, and evaluated using dynamic light scattering for their sizes and zeta potential. SEM images confirmed that the fabricated SLNs were spherical in shape. FTIR showed that there were no interactions between compounds and the lipid.
The effects of emerging contaminants on the reproductive function of marine invertebrates
(University of the Western Cape, 2025) Davidse, Morgan; Maree, Liana; Bennett, Monique
Within the environment and living organisms, emerging contaminants (ECs) are progressively detected and identified, yet effects of exposure thereof are largely unknown to the general population. The release of contaminants into the environment has shown to pose a threat to reproductive health. The marine ecosystem is presumably the final sink for a large amount of land-based chemicals, where marine species including invertebrates are continuously exposed to these contaminants. Moreover, as marine invertebrates undergo external fertilization, their gametes are at an increased risk of effects proposed to exposed contaminants. This study was set out to investigate the effects of five emerging contaminants at environmentally relevant concentrations (ng/L) detected in the False Bay area of Cape Town, South Africa, on the sperm function of two marine invertebrates’ species. Effects of diclofenac, naproxen, sulfamethoxazole, atrazine and chlorpyrifos was assessed on Parechinus angulosus and Crassostrea gigas spermatozoa.
Nano-encapsulation strategies for enhancing stability, bioavailability and therapeutic potential of fucoxanthin
(University of the Western Cape, 2026) Sibiya, Witness; Beukes, Denzil; Antunes, Edith
Marine macroalgae are an important source of structurally diverse bioactive compounds with significant pharmaceutical potential. The South African brown seaweed Sargassum incisifolium produces several lipophilic secondary metabolites, including the carotenoid fucoxanthin and prenylated meroterpenoids such as sargaquinoic acid, sargahydroquinoic acid, and sargaquinal. Although these compounds show promising antioxidant and antimicrobial activities, their practical application is limited by poor aqueous solubility, chemical instability, and low bioavailability. Nanoencapsulation within lipid-based delivery systems represents a promising strategy to improve the stability and biological performance of such hydrophobic marine natural products.
The In vitro effects of mevastatin, fenretinide and geldanamycin on MCF -7 breast cancer cell growth
(Univesity of the Western Cape, 2011) Sablay, Maymoena; Hiss, Donavon
BACKGROUND: Cancer cells usually show signs of elevated levels of HMG-CoA reductase to satisfy their increased need for lipids and isoprenoids, making them more sensitive than normal cells to the isoprenoid-depleting effects of statins. Mevastatin, a cholesterol-lowering drug belonging to the statins class, has been shown to arrest growth of HCTll6 colon cancer cells. Fenretinide, a vitamin A analogue, is a synthetic retinoid that is used in clinical trials for the treatment of several malignancies. Geldanamycin, a benzoquinoid antibiotic that has potent antiproliferative and antitumor effects, diminishes p185c-erbB2 protein tyrosine kinase in breast carcinoma cells by interacting with HSP90 which leads to the disintegration and destabilization the Rafl-HSP90 complex. PURPOSE: The aim of this study was to investigate the in vitro effects of mevastatin, fenretinide and geldanamycin, both individually and in combination, in a dose- and timedependent manner, on growth and apoptosis of the human breast cancer cell line, MCF-7. METHODS: Cell growth assays were used to monitor the growth of MCF-7 cells over a period of 5 days and a growth curve was obtained. Mevastatin, fenretinide and geldanamycin were evaluated for their antiproliferative and apoptotic effects on MCF-7 cells, using MTS assays and the Annexin- VCY3 Apoptosis Detection Kit. The combination effects of mevastatin and fenretinide on MCF-7 cell proliferation were also evaluated. Due to time constraints geldanamycin was not used in combination experiments. RESULTS: Exposure of MCF-7 cells to various concentrations of mevastatin for 24 hours produced a significant growth-limiting effect. Inhibition of MCF-7 cell growth upon treatment with mevastatin for 48 and 72 hours, showed no significant arrest of growth. After 48 hours incubation with fenretinide, MCF-7 cell growth was inhibited, but the same effect could not be demonstrated following 24 and 72 hours exposure to the retinoid. MCF-7 cells were also exposed to mevastatin, fenretinide and geldanamycin, both individually and in combination, and apoptosis was detected by fluorescence microscopy.
Exploring the place of immersive technology for improved anatomy education
(Univesity of the Western Cape, 2025) Peck, Ayesha Boomgaard; Kotze, Retha Christina
Challenges in anatomy learning, such as difficulties in visualizing anatomical structures and interpreting two-dimensional (2D) textbook images, hinder students’ comprehension and retention, driving the urgent need for innovative teaching methods in anatomy education. Anatomy education has evolved over time to now include advanced technologies to address the challenges students face when learning anatomy. However, research on such technologies and its impact on anatomy learning, especially in the South African context, is limited. Therefore, this study aimed to evaluate user experience and effectiveness of the Augmented Reality (AR) mobile anatomy application (Anat_Hub), with first-year students enrolled for anatomy at the University of the Western Cape (UWC), in motivating students and enhancing their academic performance in learning the anatomy of the musculoskeletal system, using the Attention, Relevance, Confidence, and Satisfaction (ARCS) motivational model. This study adopted a mixed-methods research approach, combining both quantitative and qualitative data to provide a comprehensive understanding of students’ learning experiences, academic performance, and motivation when using the Anat_Hub AR mobile application, in comparison to traditional learning resources such as textbooks, lecture slides, physical models, and practical specimens. A convergent parallel research design was employed, wherein quantitative and qualitative data were collected simultaneously, analyzed separately, and then integrated during the interpretation phase. To demonstrate this, a true experimental design was carried out to evaluate the experience and efficiency of the Anat_Hub AR mobile application in learning about the musculoskeletal system, impact on academic performance, and student motivation using the ARCS model. The design and development of the Anat_Hub application was influenced by cognitive model theories, including social constructivism, information processing, and metacognition, which focus on how individuals acquire and understand information through their mental processes. The research focused on three areas: (i) student demographics and experience with Immersive Technologies (ITs), (ii) student academic performance with the implementation of an AR mobile application tool, and (iii) student motivation using traditional resources versus the addition of the AR tool. In the pilot study, 40 participants were randomly assigned to a Traditional Resources (TR) (n = 20) or Anat_Hub (AH) group (n = 20). The following main study consisted of 187 participants who were randomly assigned to either the TR (n = 101) or AH group (n = 86).
The in vitro Pro-apoptotic Properties of Galenia africana on Human Breast and Oesophageal Carcinoma Cell Lines
(University of the Western Cape, 2012) Swartz, Shanel; Fielding, B
Galenia africana L. var. africana., generally known as "kraalbos," is a shrub predominately found throughout the succulent Karoo Biome of South Africa. It is known for its many anecdotal health benefits, and studies have shown that it does indeed have numerous antifungal and antibacterial activities. Pinocembrin, a polyphenol found in G. africana has demonstrated antimicrobial, anti-inflammatory, anti-tumour, antioxidant and vasorelaxative properties. The flavonoid, naringenin, also present in G. africana, is known for its antioxidant, and anti-inflammatory properties. Since both naringenin and pinocembrin demonstrated their ability to provide physiological benefits against free radicals and since cancer initiation and progression has been linked to oxidative stress, it is plausible that G. africana extract may possess anti-cancer properties. The aim of this study was to investigate the effects of G. africana aqueous extracts and selected polyphenols, pinocembrin and naringenin on human breast (MCF -7) and oesophageal (WHC05) carcinoma at 24 and 48 hrs. The objectives included (i) determining whether G. africana and its selected compounds could induce apoptosis, (ii) assess whether the flavonoids could promote synergistic pro-apoptotic effects by combining various ratios of the compounds and (iii) compare the effect of G. africana and selected compounds on various cell types
The Sensitivity of Staphylococcus aureus to pure flavonoids and synthetic antimicro bials
(University of the Western Cape, 0) Motlhalamme, Thato; Klaasen, J.; Fielding, B.; Daniels, R.
Staphylococcus aureus is an opportunistic pathogen that forms part of the normal flora of the nose, skin, mouth and other parts of the body. S. aureus infections range from superficial skin infection to more serious diseases such as pneumonia, meningitis or septicaemia. It has an ability to rapidly develop resistance to many classes of antibiotics. Methicillin resistant S. aureus (MRSA) poses a big problem because of intrinsic resistance to virtually all ~-lactams, and its tendency to develop resistance to unrelated antibiotics. Several studies have demonstrated the synergistic activity between plant extracts, their flavonoids and antimicrobial agents. Therefore this study was initiated to determine whether the flavonoids chrysin, naringenin and 7- hydroxyflavone can affect the susceptibility of methicillin sensitive S. aureus (MSSA) and MRSA in combination with methicillin and vancomycin, and also to assess the effect these flavonoids have on the expression of efilux pump genes present in the two strains. Flavonoids are a naturally occurring group of phenolic compounds which have been recognized as important due to their health benefits. Interest in the antimicrobial activity of flavonoids has grown over the last two decades and literature has shown that flavonoids such as chrysin and naringenin possess antimicrobial properties. The antibacterial activity of three flavonoids (7-hydroxyflavone, naringenin and chrysin) was determined, as well as their possible synergistic activity with ampicillin, methicillin and vancomycin against MSSA ATCC 25923 and MRSA ATCC 33591 strains, using disk diffusion and microdilution assays. Neither chrysin, naringerin nor 7-hydroxyflavone produces inhibition zones in the disk diffusion studies. Chrysin and 7- hydroxyflavanone were insoluble in solvents for microdilution studies. In the microdilution assays, naringenin showed inhibitory activity on its own and combinations with methicillin and vancomycin produced additive antibacterial activity against both MSSA and MRSA. Increase growth inhibition was especially observed when naringenin was combined with sub-inhibitory levels of the antibiotics. Efflux pumps actively transport solutes out of cells. These pumps may be specific to one agent or may transport structurally different compounds. The pumps that transport structurally different compounds are associated with multiple drug resistance. Currently more than ten efflux pumps have been described for S. aureus. The presence of efflux pump genes was assayed by PCR and quantitative RT -PCR respectively.
The in vitro effect of SARS coronavirus 2 co-infection on lytic reactivation of an oncogenic herpesvirus
(University of the Western Cape, 2025) Roman, Kayleigh
The gamma-herpesvirus Kaposi’s sarcoma-associated herpesvirus (KSHV) has oncogenic potential, particularly in immunosuppressed patients, and Kaposi’s sarcoma (KS) is the most common AIDS-related malignancy. KS is of particular significance in Sub-Saharan Africa, where both HIV and KSHV prevalence are high. KSHV displays a biphasic life cycle consisting of latent and lytic stages, and the lytic phase is associated with active virus replication and disease pathology. The emergence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, presents an additional undetermined risk of cancer development, affecting already vulnerable populations. Recent clinical studies suggest that there may be potential interplay between SARS-CoV-2 infection and reactivation of opportunistic herpesvirus infections. The present study aimed to design an in vitro model for investigating the effects of SARS-CoV-2 co-infection on KSHV lytic reactivation. Vero E6 cells were stably infected with rKSHV allowing for the establishment of latency in the cells (Vero E6 rKSHV), with the potential for reactivation upon exposure to specific conditions. Vero E6 rKSHV cells were used to determine if infection with SARS-CoV-2 live virus, or infection with a pseudovirus bearing SARS-CoV-2 spike(S), or just SARS-CoV-2 S protein treatment alone could initiate KSHV lytic reactivation. Both live virus and pseudovirus infection of the latently infected cells was sufficient to induce KSHV lytic reactivation. Importantly, no reactivation was observed in response to a pseudovirus bearing an unrelated envelope protein. Direct treatment with S protein also did not produce the same effect. We speculate that the KSHV reactivation seen in this cell model was induced by an indirect S protein-mediated mechanism. The data gathered in this study contributes to the current understanding of KSHV lytic reactivation in the context of respiratory virus infection. While the underlying mechanisms require further investigation, this study provides evidence supporting the clinical observations of KSHV lytic reactivation in COVID-19 patients.
Developing a high throughput screening assay for the discovery of SARS-CoV-2 entry inhibitors
(University of the Western Cape, 2025) Adams, Ethan
Despite the development and global distribution of vaccines, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, continues to pose a public health challenge. Infections continue to persist today due to rapid mutation in the spike (S) protein, the target for vaccine-induced neutralizing antibodies. These mutations result in reduced vaccine efficacy and subsequent immune evasion by the virus, underscoring the urgent need for antiviral drugs to expand upon disease therapies. Identification of novel antiviral compounds can be achieved through the development of a robust assay suitable for high throughput screening (HTS). This assay must demonstrate high reproducibility and low variability to ensure reliable screening. To evaluate assay robustness, the statistical parameter Z-factor (Z’) was employed. This study aimed to develop a HTS assay to measure SARS-CoV-2 entry, and to validate the assay for HTS applications. To assess SARS-CoV-2 entry, a vesicular stomatitis virus (VSV)-based pseudovirus system was utilized, enabling work under biosafety level 2 (BSL-2) conditions.
The mechanisms of leptin induced steroidogenesis collapse in TM3 Leydig cells and an investigation into the potential protective role of Sutherlandia frutescens extract
(University of the Western Cape, 2025-01) Menyane, Lutho
Metabolic syndrome, often accompanied by hyperleptinemia, is frequently implicated in male hypogonadism, impacting approximately 40% of men aged 45 and older. Elevated leptin levels adversely affect Leydig cell function. This study aims to investigate leptin's role in Leydig cell dysfunction and explores the potential protective effects of Sutherlandia frutescens against leptin-induced hypogonadism. Two models were employed: a basal model with no hCG stimulation and another model stimulated with hCG. TM3 Leydig cells were exposed to increasing leptin concentrations (0.001-100 ng/ml) for 24, 48, and 72 hours. Morphological, proliferative, and apoptotic effects on TM3 cells were assessed using light microscopy, TUNEL, and ApoTox assays and caspase 3/7 activation. Steroidogenesis was evaluated by quantifying testosterone concentrations, and oxidative stress was determined using a dihydroethidium (DHE) staining kit. In the hCGstimulated model, the potential protective effects of S. frutescens were evaluated using selected assays. Statistical analysis was performed using MedCalc version 16.4.3, and significance was set at p < 0.05. Leptin exposure led to time and dose-dependent morphological changes, reduced viability, increased apoptosis, and elevated ROS generation in both models. Significant DNA damage and decreased testosterone levels were also observed across a wide range of leptin concentrations, indicating severe Leydig cell dysfunction. Though the in vitro exposure to leptin induced TM3 Leydig cell dysfunction through oxidative stress, apoptosis, and impaired steroidogenesis.
Cardiometabolic risk factors present in pubertal adolescents in association with perinatal nicotine exposure and rapid weight gain: comparison study
(University of the Western Cape, 2025) Parker-Mansoor, Sabreen
Background: The global and local rise in morbidity and mortality related to cardiovascular and cardiometabolic disease presents a major public health concern. In South Africa, lowincome communities are disproportionately affected due to limited access to healthcare, nutritious food, physical activity, education, and increased exposure to modifiable risk factors like tobacco use. These socioeconomic challenges contribute to the increasing burden of obesity, particularly among youth. Obesity and related cardiometabolic risk factors tend to track from childhood into adulthood, highlighting the importance of addressing adolescent health. While rapid weight gain (RWG) in infancy and early childhood has been independently associated with obesity and adverse cardiometabolic outcomes, limited research has explored how early and late RWG influence adolescent cardiometabolic health in South African populations. Additionally, prenatal nicotine exposure is a well-established risk factor for increased adiposity, cardiometabolic dysfunction, and its connection to infant RWG. However, the sex-specific impacts of prenatal nicotine exposure and RWG during adolescence remains underexplored. This study aimed to determine whether RWG in pubertal adolescents was associated with an increased risk of adolescent obesity and other cardiometabolic risk factors, such as elevated blood pressure, increased waist circumference (WC), greater skinfold thickness, and its relation to in utero nicotine exposure. Methods: This study followed a casecontrol design on 100 adolescents from a low socio-economic income setting in Cape Town, South Africa. Interviews were conducted with guardians and participants to collect health and lifestyle information regarding physical activity, diet, smoking during pregnancy, and SES. Anthropometric measurements were taken, such as weight and height for body mass index (BMI) calculation, triceps and subscapular skinfold thickness (SFT), and WC. Blood pressure measurements such as systolic and diastolic blood pressure, mean arterial pressure (MAP), and heart rate were taken from adolescent participants. Retrospective data was collected using the weight-for-age charts from each participant's Road to Health clinic booklets for RWG calculation. Data was analysed using SPSS version 30.
Synthesis of Lepidium meyenii (Maca) containing liposomes and its possible applications in the treatment of prostate cancer
(University of the Western Cape, 2024) Solomon, Lyle TB
Nanotechnology is the science and engineering involved in the design, synthesis, characterization and application of materials and devices with at least one of their dimensions on the nanoscale (1-100 nanometres). Nanotechnology is a booming field in science, presenting with a wide variety of applications. Liposomes are multi-layered nanoparticle structures that are known to be excellent carriers for a variety of drugs to specific target sites, including cancer cells. The most recent and well-known application of liposomes came with the record-breaking creation of the SARS-CoV-2 (Coronavirus/ COVID-19) vaccines created by Pfizer-BioNTech and Moderna. Studies have confirmed that Lepidium meyenii (Maca) possesses the ability to scavenge free radicals and protect cells against oxidative stress. The liposomes’ biocompatible and biodegradable nature would be a marriage of traditional and modern medicine, united to possibly create a safer and more efficient treatment options for prostate cancer. Materials and methods Liposomes encapsulated with Lepidium meyenii (Red Maca) extract were synthesized using the thin lipid film hydration technique, at a 7:3 w/w ratio. Characterization of the produced nanoparticles was performed using the Malvern Zetasizer NanoZs. This device determines the size, size-distribution/ polydispersity index (PDI), surface charge/zeta potential and stability of nanoparticles to assess the nanoparticles performance for possible medicinal applications. The effects of Maca-encapsulated liposomes were then investigated alongside the raw Maca extract on a cellular level using the LNCaP prostate cancer cell line, where the cell morphology, viability and wound healing assay were assessed over periods of 24 and 72 hours.
Exploring South African honey: a focus on chemical composition and antimicrobial activity against pathogenic organisms
(University of the Western Cape, 2025) Rohman, Tanya;
Honey has been used as an alternative medicinal agent for many years. Several factors give honey its antimicrobial ability including the presence of hydrogen peroxide, phenolic compounds, low moisture content, low pH, and high sugar concentrations. In South Africa, data on the antimicrobial activity of indigenous honey is limited, as there are many floral sources that are still underexplored. Additionally, very few studies highlight the influence that antimicrobial properties may have on the honey’s antimicrobial activity. The aim of this study was to investigate whether ten honey samples collected from different regions within South Africa possess antibacterial activity against clinically relevant pathogenic bacteria, namely Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli and Pseudomonas aeruginosa, and to determine whether the physicochemical properties of the honey samples collected influenced their antimicrobial activity. Samples were mainly collected from regions within the Western Cape and Northern Cape. The phenol equivalence assay was employed to assess antibacterial activity at honey concentrations ranging from 5 – 50% (w/v). Physicochemical properties were assessed, including moisture content, colour intensity, pH, and chemical composition. Results of this study revealed that S. aureus was the most susceptible bacterium and P. aeruginosa the least. Honey obtained from the Succulent Karoo region exhibited exceptional antibacterial activity, whereas most Graafwater region samples exhibited poor or no activity. Despite no statistical correlation being observed between the physicochemical properties and the antibacterial activity of the honey samples, all Succulent Karoo samples (Niewoudtville – Loeriesfontein and Vanrhynsdorp – Niewoudtville) possessed a high pH (4.36 and 4.59) and moisture content (4.42% and 8.39%) and were darkest in colour (211.89 mm and 323.27 mm) compared to other samples. Furthermore, 1H NMR analysis revealed that Succulent Karoo samples are chemically unique compared with other honeys, with unidentified resonances that could correspond to bioactive compounds. In conclusion, this study revealed that honey derived from the Succulent Karoo region in South Africa has the potential to be used therapeutically and provides insight on the chemical composition of South African honeys, contributing towards the chemical profile of South African flora
Exploring the in vitro effects of chronic methamphetamine exposure on selected cancer cell lines
(University of the Westen Cape, 2025) Sasman, Sasha-lee
Methamphetamine (METH) is a potent psychostimulant widely associated with neurotoxicity and oxidative stress. Although its acute effects are well documented in multiple organ systems, the cellular consequences of chronic METH exposure in cancer biology remain poorly defined. Understanding how tumour cells respond to sustained psychostimulant-induced stress may provide insight into metabolic and redox adaptations relevant to cancer progression. Five cancer cell lines, namely MCF-7, MDA-MB-231, HeLa, U87, and SK-N-BE-2 cancer cells were exposed to physiological and supraphysiological concentrations of METH (0.1-250μM) chronically for 96 hours. Cell viability and proliferation were assessed using the trypan blue exclusion assay. Mitochondrial activity was evaluated using the XTT assay. Intracellular reactive oxygen species (ROS) levels were quantified using the H₂DCFDA assay. All measurements were analysed relative to controls to identify dose- and time-dependent trends. Across all five cell lines, chronic METH exposure did not induce cytotoxicity, as dead cell numbers remained comparable to controls at all time points. Instead, METH produced cytostatic modulation varied by cell line and concentration. All lines exhibited delayed mitochondrial hyperactivity, suggesting potential metabolic compensation in response to sustained stress. ROS measurements revealed oscillatory redox dynamics, characterised by early ROS perturbations followed by significant ROS suppression at later time points, indicating activation of antioxidant responses. Collectively, the data show that cells respond to repeated METH exposure not by undergoing cell death but by adjusting proliferation, mitochondrial function, and redox homeostasis. Chronic methamphetamine exposure alters cancer cell types’ physiology differently through cytostatic, metabolic, and redox adaptation, rather than through direct cytotoxicity. These findings highlight the need for deeper mechanistic studies into how psychostimulant use may influence cancer cell behaviour, metabolic resilience, and stress-response pathways.
The implementation of in vitro assays to screen environmental samples for male reproductive toxicity
(University of the Western Cape, 2010) Ebrahim, Mozaffar
Endocrine–disrupting compounds (EDCs) are exogenous compounds/chemicals which interfere with, or have adverse effects on the production, distribution and function of natural hormones, thereby affecting normal endocrine activity, health and quality of life of both humans and wildlife. The reproductive system is highly susceptible to EDCs due to it being controlled by an array of hormonal signals. The effects of EDCs on the male reproductive system include infertility, decreased sperm count, function and morphology, abnormal development of secondary sex characteristics, reproductive function and sexual behaviour as well as decreased libido. There are various sources by which EDCs enter the environment which include effluents from several industries (mining, agriculture, smelting, hazardous waste sites, manufacturing industries, etc.), sewage treatment effluents, urban and agricultural runoff and effluents which include natural and pharmaceutical chemicals excreted in the urine of humans and domestic livestock, pesticides, polychlorinated biphenyls, dioxins, plasticizers, surfactants, etc. Humans and animals can also be affected by EDCs by consuming food containing endocrine active substances. The growing concern regarding adverse effects due to EDC exposure of humans and wildlife, as well as the increased incidence of EDC contamination has prompted extensive research into the development and validation of screening tests to detect and monitor known EDCs and new substances with endocrine-disrupting capability. These screening tests involve assessing the effect of known and potential EDCs on reproductive function and development as well as hormone production. To assess the effect of EDCs on the reproductive system different methods are employed which include in vitro, in vivo and ex vivo methods. In vitro methods have been suggested as a suitable screening tool for EDC monitoring due to low costs, reduced animal usage, the use of standard and basic equipment as well as the ability to screen a large number of samples with multiple endpoints. Of the available in vitro methods, the minced testes method has been suggested as the most suitable method for screening EDCs and for this reason has been employed in this study. The aim of this study was thus to employ a minced testes method to screen samples for male reproductive toxicity using cell viability and hormone production (testosterone and estradiol) as endpoints. The first objective of this study was to optimize an in vitro testicular cell culture assay by determining both optimal luteinizing hormone (LH) concentration and incubation time needed for testosterone production. Testicular cell cultures were prepared and cells were treated with varying concentrations of LH (10, 1, 0.1, 0.01 and 0 mu/ml) and incubated for 4 hours and 20 hours. Testosterone production was evaluated for each incubation period. Testosterone production was significantly increased for both incubation periods at all LH concentrations tested as compared to the control. For both incubation periods, there was no significant difference in testosterone production between the different LH concentrations tested. From the data obtained, the 4 hour incubation period as well as the LH concentration of 10 mu/ml were selected as optimal for the testicular cell culture assay. The second objective of this study was to determine the effect of Tulbaghia violacea Harv. on the male reproductive system. T. violacea is a plant species indigenous to southern Africa and is used locally as a herbal remedy/medicine to treat several ailments. Cells were treated with varying concentrations of the T. violacea ethanol extract (with/without LH-treatment) and incubated for 4 hours. Hormone production and cell viability were evaluated. The results obtained from this pilot in vitro study demonstrated that the ethanol extract of T. violacea has androgenic properties by significantly increasing LH-induced testosterone production in mouse testes with no significant change in cell viability. The third objective of this study was to assess the effect of Sutherlandia frutescens(L.) R.Br and Artemisia afra Jacq. Ex Willd. on the male reproductive system. S. frutescens and A. afra are also plant species indigenous to southern Africa and used locally as a herbal remedy/medicine to treat several ailments. Ethanol extracts of each plant was prepared and cells were treated with varying concentrations of each extract (0, 156.25, 312.5, 625, 1250, 2500 and 5000 µg/ml) with or without LH-treatment and incubated for 4 hours. Cytotoxicity by LDH measurement and hormone production (testosterone and estradiol) were endpoints that were evaluated. The results obtained showed that the ethanol extracts of both plants are not cytotoxic to testicular cells and that A. afra decreases testosterone production at high concentrations. The fourth and final objective of this study was to assess the acute effect of four heavy metals, namely manganese, copper, cadmium and magnesium on the male reproductive system. These heavy metals are used extensively in manufacturing and mining industries. Cells were treated with varying concentrations of each metal salt (200, 100, 50, 25, 12.5, and 6.25 µM) with or without LH-treatment and incubated for 4 hours. Endpoints evaluated included cell viability, testosterone and estradiol production. The results obtained showed that manganese, cadmium and copper are highly toxic to testicular cells in vitro and therefore may potentially cause reproductive toxicity.
An investigation of student engagement, learning strategies, and challenges in anatomy learning within the context of South African higher education: insights from Mind, Brain, and Education (MBE) Science
(University of the Western Cape, 2025) Fritz, Kaylyn Anastacia
Background: Human anatomy forms the basis of all undergraduate medical and health science degrees; however, the content-heavy nature of the discipline is often a challenge. Therefore, it is imperative that higher education institutions understand how students prefer to assimilate new information and adapt content delivery approaches to their unique experiences and needs in order to support academic success. Hence, in an effort to enhance the teaching and learning process, this research study aimed to investigate how student engagement, learning strategies, and challenges influenced the anatomy learning experience of first-year students at the University of the Western Cape (UWC). The Mind, Brain, and Education (MBE) Science theoretical framework was used to inform the study aims and objectives. Study design: Using a concurrent mixed-methods approach by means of an online Google Form questionnaire, qualitative and quantitative data were simultaneously collected and then analysed to draw comprehensive conclusions. The study examined independent variables including age, home language (HL), method of payment (MOP) for tuition fees, and degree programme in relation to the dependent variables including student engagement (access, use and preference) with pedagogical approaches, perceived effectiveness of pedagogical approaches, perceived benefits of pedagogical approaches, learning strategies, and perceived influences that affect the anatomy learning experience. Data was obtained from 126 participants (during 2022 - 2023) who were randomly assigned to the pilot study group (n = 20) and main study group (n = 106). All procedures were approved by the Humanities and Social Sciences Research Ethics Committee (HS21/10/38) at UWC. Main study results: Participants predominantly accessed and used the face-to-face theory lecture teaching method and the teaching slides (ppt/pdf) resources. They also preferred face-to-face teaching methods (theory lectures, 29.2%; practicals, 16.0%), and also found it to be more effective learning measures (theory lectures, 91.5%; practicals, 98.1%) than the alternative live online methods. In terms of teaching resources, the majority of participants preferred teaching slides (ppt/pdf) (10.4%) and found it to be an effective learning measure (92.5%). When studying anatomy, participants commonly made use of teaching slides (92.5%), narrated pre-recorded lectures (69.8%), and textbooks or e-textbooks (55.7%). Learning strategies such as spaced practice (27.4%, 3.70 ± 1.91) and elaboration (19.8%, 4.13 ± 1.40) were strongly preferred among participants.
Galenia africana extract as an alternative to typical azoles against Candida species
(University of the Western Cape, 2025) Mouton, Charnice Rene’
Candidiasis is a common infection caused by Candida species, often associated with immune compromised patients. Due to the prevalence of candidal resistance to typical azole treatments, alternative forms of therapies should be investigated. The use of medicinal plants as an alternative form of therapy has become a topic of interest in the scientific community. Galenia africana has shown a lot of potential as an antimicrobial plant extract. In this study, the antifungal activity of the ethanolic and ethyl acetate extraction of Galenia africana was investigated against fluconazole-resistant and susceptible Candida species. High-performance liquid chromatography and nuclear magnetic resonance were employed to separate, isolate and purify the active compounds of Galenia africana followed by evaluating the antifungal activity using broth microdilution, synergistic and time kill assays. Three compounds were isolated from Galenia africana, identified as (S)-5,7-dihydroxy flavone (1), (E)-2',4'-dihydroxychalcone (2), and (S)-2',5,7,-trihydroxyflavanone (3). The results showed significant antifungal activity below 500μg/ml which confirms that Galenia africana can be used as a potential antifungal against fluconazole resistant strains of Candida.
Aggregatibacter actinomycetemcomitans serotypes in gingival crevicular fluid of mothers delivering preterm.
(University of the Western Cape, 2024) Messeir, Ilze
Preterm birth (PTB), defined as delivery before 37 weeks of gestation, is a significant global public health concern. It has a tremendous impact on both the healthcare system and the individual families affected. Low birth weight (LBW), is a direct consequence of PTB or intrauterine growth restriction, and is a major determinant of neonatal infant morbidity and mortality. The primary aim of this study was to determine if the prevalence of Aggregatibacter actinomycetemcomitans (Aa) serotypes in gingival crevicular fluid (GCF) stored for more than ten years could be used as microbial biomarkers to predict preterm delivery. The study samples included 185 samples from “preterm birth” and “normal birth” mothers with pregnancy gingivitis.
Aspects of the interrelation between hypertension and insulin resistance: A preliminary study
(University of the Western Cape, 2024) Nwabuisi Osuafor, Godswill; Dietrich Daneel
It is well known that some genetic factors and dietary factors. such as excessive salt intake and excessive caloric intake (resulting in obesity) are risk factors for hypertension. Fifty percent of all hypertensive patients are also insulin resistant. Both hypertension and insulin resistance are again risk factors for other cardiovascular diseases such as atherosclerosis and heart fai lure. The nature of the association between hypertension and insulin resistance has not heen clearly elucidated. Spontaneously hypertensive rats are the ideal models to study the aspects of the relationships between hypertension and insulin resistance. Models of high-fat feeding induce obesity, hypertension and insulin resistance and are thus used extensively to study hypertension because these models closely mimic some of the renal and cardiovascular changes found in human hypertensive pati ents. The present study was initiated to evaluate if insulin resistance will develop within 6 weeks in a model of high- fat diet induced hypertension and if so. to determine whether captopril will affect the presence of insulin resistance. This model should in future be used to study vascular reactivity to phenylephrine (PHE), acetylcholinc (AC!-1) and sodium ni troprusside (S~P) in hypertensive animals in the absence or presence of insulin resistance and in normotensive insulin resistant animals.
Isolation and characterization of attachment-induced regulatory elements in Pseudomonas aeruginosa P AOI
(University of the Western Cape, 2024) Weyers Jakobus Barnad; Brozel V. S.
Bacteria exhibit a remarkable tendency to attached to biological (biotic) and abiological (dead) surfaces (Zobell. 1943). This tendency of bacteria to interact with surfaces appears to be increased or amplified under certain "stress" conditions. Environmental conditions implicated in promoting bacterial attachment and biofilm growth include nutrient limitation or starvation, increased osmolarity, membrane perturbation, and harmful chemicals (Costerton et al. , 1987; Marshall, 1992). In addition to environmental condition that enhance bacterial attachment. The interaction of bacteria with biotic surfaces appears to be very complex due to the interaction of prokaryotic and eukaryotic cell surface receptors with the host cell, and would therefore be very specific (Hoepelman and Tuomanen. 1992). The current body of data suggests that bacteria attach to surfaces under environmental ··stress·' conditions in order to cope better with the harsh environmental conditions. Attached bacteria would, therefore, have advantages over their planktonic counterparts during growth under environmental stress conditions. This is evident from reports stating that biofilms constitute major self purification systems with the abi lity to minimize the build-up of pollutants, transform inorganic compounds and biodegrade organic compounds (Marshall. 1992). Bacteria in biofilms are generally much more resistant to biocides and antibiotics than are their planktonic counterparts (Costerton et al., 1987). Attached bacteria have a protection barrier against phagocytosis, bacteriophages. antibiotics. biocides. surfactants and antibodies (Costerton et al .. 1995; Dooley and Trust, 1988; Sleyter and Messner, 1983).

Browse

Recent Submissions