Targeted photodynamic therapy of metastatic melanoma cancer and cancer stem cells

Abstract: Metastatic melanoma is highly aggressive and has been recorded by the American Cancer Society as being the most common cause of skin cancer associated deaths (ACS., 2020). Tumours are heterogeneous and encompass various dynamic subpopulations of cells, one of these being cancer stem cells (CSCs). Cancer stem cells have the potential to cause cancer relapse and metastasis, as well as being resistant to multiple forms of therapy (Nguyen et al., 2015). Melanoma CSC populations have been identified and linked to tumor progression, immune-evasive behavior, drug resistance, and metastasis. Intra-tumour heterogeneity, which refers to how different subpopulations inside and between tumor lesions interact, has a significant impact on the tumor's response to pharmacological therapy in melanomas. The present study evaluated the effects of Photodynamic Therapy (PDT) using Aluminum phthalocyanine (AlPcS4Cl) photosensitizer (PS) at 673.2 nm in targeting melanoma cells (A375) and their stem cell population. The use of human malignant melanoma cell cultures (A375 cells, alongside with fibroblast (WS1) cell cultures (normal cells) was employed. These were grown in a complete liquid medium incubated at 37 °C, 5% CO₂ and 85% humidity. Dose response studies were performed on the total cell populations by increasing doses of AlPcS4Cl. Post-irradiation signs of cell death were determined using microscopy, Trypan blue viability, ATP, and LDH assays. The increasing cell death of treated A375 and WS1 cells was directly proportional to increasing dose responses observed. Changes post-irradiation were realized through cell viability testing with significantly increased damaged cells taking up Trypan blue dye. Treatment group cells with a dose of 20 μM AlPcS4Cl indicated 68.25% viability and for a dose of 40 μM, 35% viability. This suggests that PDT is most effective at a higher dose but also harmful to normal cells at a dose of 40 μM. A lower dose range was used for A375 cells which showed a significant decrease in cell viability for a dose of 20 μM, showing only 55.25% viability. The impact of PDT on metastatic melanoma was highlighted through its target specific effects causing morphological changes, dose dependent decreases in ATP, and increased LDH content released due to cytotoxicity. Current treatments have limited...M.Tech. (Biomedical Sciences

An assessment of environmental factors affecting the delivery practices of hospital-based intrapartum care : a case of rural Ketté District Health Service in Cameroon

Abstract: Background: In 2017, the World Health Organization reported more than 295,000 maternal deaths on a global scale. The majority of these largely preventable misfortunes occurred within the intrapartum period. Interestingly, a significant relationship between environmental factors and hospital-based intrapartum care has been established in some studies. Objective: This study sought to assess the effect of environmental factors on maternal outcomes and the use of intrapartum healthcare services at the Ketté District Hospital. Methods: This was a cross-sectional . The study sampled 471 women presenting for peripartum care at the Ketté District hospital. A pilot study was initiated prior to data collection. The results were analysed at 95% confidence interval (CI) using EPI Info and the Statistical Package for the Social Sciences. Charts, tables and logistic regression were used to relate variables to observed outcomes. Results: Of the study participants, 24.2% (n=114) had a history of maternal complications. Socio-demographic characteristics associated with higher odds for maternal complications included age group 18-25 years (OR 1.89, 95% CI 1.16-3.11) where 26-33 years was the reference group, family size greater than 6 (AOR 2.17, 95% CI 1.18-3.98) where 3-4 persons was the reference group and being unemployed (AOR 2.46, 95% CI 1.12-5.41) where being self-employed was the reference group. One major factor associated with maternal complications was a travel distance of over 5 km from the health facility (OR 3.12, 95% CI 1.07-9.13) where a distance of 1-2 km was the reference. Obstetric and delivery determinants associated with maternal complications included delivery being assisted by a traditional birth attendant (AOR 3.70, 95% CI 1.71-8.04) where delivery at a health centre was the reference group. The perceived importance of environmental factors for ANC frequency showed greater odds for maternal complications when road quality was important (AOR 4.33, 95% CI 1.62-11.57); when travel time was important (OR 2.85, 95% CI 1.57-5.18); when travel distance was very important (OR 6.65, 95% CI 3.62-12.25); and when season was important (OR 3.59, 95% CI 1.91-6.78). Conclusion: Maternal outcomes were significantly influenced by distance, route network, and season of delivery. The implementation of sustainable measures via road maintenance and motorised transportation could greatly improve peripartum outcomes.M.A. (Public Health

Secondary metabolites produced by Staphylococcus species and their antimicrobial activities against ESKAPE group of bacteria

Abstract: Background: ESKAPE-related infections pose a serious challenge to the health sector as they are known to be resistant to the current antibiotics. This led to the investigation of secondary metabolites from Staphylococcus species [(S. saprophyticus (ATCC 35552), S. epidermidis (ATCC 51625) and S. aureus (isolated from milk)] as a possible solution to alleviate ESKAPE-related conditions. Methods: Secondary metabolites were screened by Gas chromatography coupled with mass spectrophotometry (GC/MS/MS), then purified using silica gel and thin layer chromatography plates. The normal distribution for prominent secondary was achieved by using the Kruskal Wallis Test. Compounds were then identified using nuclear magnetic resonance and such were tested for antimicrobial properties against ESKAPE bacteria by autobiography and microtiter plates respectively. The cytotoxicity studies were carried out against Vero cells using 3-(4,5-dimethyl-2-thiazole)-2,5 diphenyl-2- H bromide tetrazolium (MTT) assay. The Spearman`s correlation analysis method was used to evaluate if values were statistically significant. Results: Different classes of compounds were identified, among others were hetrocyclic compounds, amino acid and alcohols. The data analysis for prominent compounds revealed the percentage peak area average was not normally distributed. To achieve normal distribution for prominent secondary, Kruskal Wallis Test was carried to reach the value that was statistically significant (p= 0.396). The identified compounds include: polycyclic aromatic hydrocarbon (Fluoranthene) and (heterocyclic compound) 3-methyl-2-phenyl- 1H-pyrrole from S. aureus. Two compounds from S. epidermidis were: amide (oleamide) and fatty acid (ester methyl palmitate), and four from S...D.Tech. (Biomedical Technology

A comparative study between virtual and non-virtual workouts pre, during and post Covid-19 South African lockdown

M.Phil. (Sport Science)Abstract: The purpose of this study was to draw a comparison between virtual and non-virtual workouts that took place during the different lockdown levels in South Africa implemented during the COVID-19 pandemic in the country, during which various restrictions were put in place. The study also examined the different exercise intensities and frequencies that took place prior to lockdown, during lockdown and the workout structure that followed post hard lockdown in South Africa. A quantitative research design was utilised, with data collected by means of an internet-based survey. A total of 120 participants completed the survey with questions focusing on exercise adherence prior to, during and post-lockdown. The majority of the participants who completed the survey resided in Gauteng (86,7%) and were between the ages of 21 and 30 (64,2%). Prior to the COVID-19 lockdown in South Africa (March 2020), 88,3% of participants were already physically active. During lockdown (levels 1 to 5) the workout regimen enjoyed most often was workouts done virtually (52%). Participants who preferred non-virtual workouts were more intrinsically motivated (M = 5,92; SD = 0,91) than those who preferred virtual workouts (M = 5,48; SD = 1,10; p = <0.05), Men (M = 5,99; SD = 0,90) were more intrinsically motivated than women (M = 5,52; SD = 1,07; p = <0.05). Vigorous-intensity exercise (+1,6%) and moderate-intensity exercise (+2,5%) showed an increase in prevalence compared to pre-lockdown intensities.When comparing exercise frequency for 4 days a week or fewer pre and during lockdown, there was an increase in vigorous activity (+2%) and a decrease in moderate-intensity exercise (-4,3%) During the easing of restrictions (post the hard lockdown period in South Africa), participants continued with virtual and non-virtual home workouts. This was despite 41% having returned to fitness facilities and gyms. The implications for this study support the self-determination theory because, in times of lockdown and movement restrictions, individuals were self-determined and intrinsically motivated to continue with or begin to exercise, despite living through a pandemic

Application of virtual reality for enhanced learning integration in higher education institutions

Abstract: Time constraints frequently hamper information assimilation during class activities when carrying out physical experimentations. Due to limited class time, educators find it challenging to keep track of their students’ learning progress. At the administrative level, a shortage of educational technology financing limits both educators’ ability to optimally influence knowledge and the learners’ ability to integrate what has been taught through abstract means thoroughly. The inability of educators and learners to communicate effectively undermines the primary goal of learning because they cannot meet the diverse needs of students. Higher education institutions frequently use obsolete equipment and are not updated on virtual reality technology. As a result of these considerations, a virtual reality (VR) simulation was used in this study. As some notable success rates were achieved, virtual reality technology is promising if effectively adapted to the curriculum. This is covered in the literature review of this dissertation. This study identified the steps and processes involved in creating a virtual reality experience for information integration and developing a virtual reality application. It also looked into the possibility of using the developed application as a learning tool. This application is ideal for teaching students about electric induction motors with variable frequency drives. The virtual reality system used in this study combined a virtual game engine simulator, Unity 3D, and Blender modelling software to develop the application. To convert the development to an Android application, a cross-platform software development kit was used. The developed android application simulates a virtual reality experience that replaces the real world with a virtual world and allows the user to experience the state of being in the virtual world with a head-mounted display in order to understand the operation of an electric motor with a variable frequency drive.M.Phil. (Mechanical Engineering Science

Assessing the water quality of selected public swimming pools within the Johannesburg area of the Gauteng province, South Africa

Abstract: A number of contaminants in public swimming pools have been recognised globally, all of which are detrimental to the quality of such amenities as well as to human health. Thus, swimming pool water may serve as a medium for the transmission of waterborne pathogens amongst swimmers unless appropriate preventive measures are properly implemented. Moreover, at certain times various researchers have linked the poor quality of swimming pool waters to pathogenic outbreaks. Despite such negative health impacts, studies focusing on the water quality of swimming pools are limited in South Africa. Even so, the quality of drinking water in most African countries is alarming, let alone the quality of public swimming pool water. As a result, the present study was carried out to assess the water quality of selected public swimming pools within the CoJ Metropolitan Municipality, in the Gauteng province in South Africa. The swimming pool water’s pH, electrical conductivity, temperature, free available chlorine, total chlorine, alkalinity, water hardness, and cyanuric acid were measured on site while the collected water samples were analysed at the laboratory for the presence microbiological agents (i.e. E. coli and total faecal coliforms). The results showed different degrees of unsatisfactory and non-compliance across all selected public swimming pools. The findings also indicated the presence of waterborne pathogens largely due to inadequate disinfection. It has also been established that the existing recirculation-filtration systems are not always working optimally (due to electrical load shedding) and water chemical imbalances, thus resulting in water quality non-compliance. Unfortunately, surrounding communities use such facilities for recreation and leisure time, despite their health and hazard potential. Based on the results of this study, it is recommended that the swimming pool waters must be effectively treated to inactivate and kill microbes, therefore providing chemically balanced water. Furthermore, water quality testing kits and water quality sensors can be used to measure multiple physical and chemical water quality parameters simultaneously and to provide instant results.M.Sc. (Environmental Management

Departments' instructional leadership role in Primary Schools

Abstract: The South African education system is characterised by poor learner performance; the structure of Continuing Professional Teacher Development (CPTD) programmes; poor communication among various stakeholders; inadequate resources; incompetent heads of departments (HoDs); inferior teacher training; and the lack of support from the Department of Education (DoE). Using qualitative research within an interpretivist paradigm, this study explored teachers' experiences of their HoDs as instructional leaders in primary schools. HoDs are unclear of their roles and responsibilities, and they therefore have problems in balancing management demands and curricula and instruction. HoDs should take on an instructional leadership role and ensure that teachers provide effective teaching to improve learner performance. When teachers experience problems in teaching, HoDs are required to provide professional development programmes. Twelve teachers, purposefully selected from four primary schools, were interviewed. Three themes emanated from the study: Understanding the concept instructional leadership; the instructional leadership roles of HoDs; Teachers’ expectations of their HoDs in their instructional leadership role. Findings showed that participants had a good understanding of the concept instructional leadership and were also aware of the importance of HoDs taking on an instructional leadership role. One of the primary responsibilities of HoDs is to effectively implement the Integrated Quality Management System (IQMS) with the view to identifying the pedagogical needs of teachers and providing CPTD. The study also showed that the DoE provided insufficient professional support to HoDs and teachers. The study recommends that HoDs and teachers need to effectively implement the IQMS policy. Teachers must carefully select an effective staff development team (SDT) which includes the HoD and peers who have expertise in the teacher’s field. The HoD and SDT should work collaboratively to provide professional development programmes. Key words: professional development, head of department, instructional leadership, Integrated Quality Management System.M.Ed. (Educational Leadership and Management

Water and Wastewater Digital Surveillance 1 for Monitoring and Early Detection of 2 the COVID-19 Hotspot: Industry 4.0

Abstract: There are a high number of COVID-19 cases per capita in the world that goes undetected including clinical diseases compatible with COVID-19. While the presence of the COVID-19 in untreated drinking water is possible, it is yet to be detected in the drinking-water supplies. COVID-19 viral fragments have been found in excrete, this call for wastewater monitoring and analysis (wastewater surveillance) of the potential health risk. This raises concern about the potential of the SARS-CoV-2 transmission via the water systems. The economic limits on the medical screening for the SARS-CoV-2 or COVID-19 worldwide are turning to wastewater-based epidemiology as great potential tools for assessing and management of the COVID-19 pandemic. Surveillance and tracking of the pathogens in the wastewater are key to the early warning system and public health strategy monitoring of the COVID-19. Currently, RT-qPCR assays is been developed for SARS-CoV-2 RNA specimen clinical testing and detection in the water system. Convectional wastewater treatment methods and disinfection are expected to eradicate the SAR-CoV-2. Chlorine, UV radiation, ozone, chloramine is been used to inactivate and disinfect the water treatment system against the SARS-CoV-2. Water management and design of the water infrastructure require major changes to accommodate climate change, water cycle, reimaging of digitalization, infrastructure and privacy protection. The water digital revolution, biosensors and nanoscale, contact tracing, knowledge management can accelerate with disruption of the COVID-19 outbreak (water-health-digital nexus)

Exploring hydropolitics and expressions of citizenship : three communities in Madibeng, South Africa

Abstract: This study set out to investigate forms of expression in the context of Madibeng Local Municipality hydropolitics, paying particular attention to Damonsville, Mothutlung and Mmakau. Madibeng was an ideal location for this study because there is evidence that the local municipality has been struggling to provide water services. This has culminated in toyi-toying – one form of expression. I adopted a qualitative research methodology underpinned by a social constructionist epistemology. The primary data collection method was in-depth interviews supplemented by observation, field notes (journal entries) and photography. I selected twenty-seven participants purposively. Major findings point to the fact that the participants viewed water services as grossly inadequate – they indicated that their communities experienced rampant and prolonged water interruptions and poor water quality. They perceived the municipality officials as contributing to poor water service delivery through corruption and financial mismanagement of the local municipality. Water infrastructure in the community was noted to be worn and obsolete. In addition to this, I found that some participants held the view that citizenship spaces in the communities were on the decline: politicians highjacked community meetings, there was a rise in gangsterism, and some community members contested “good citizenship” practices like paying for water. While some community members favoured toyi-toying, a constitutional right, others did not, in fear of getting hurt, or worse, dying. From the findings, I make three contributions to the body of knowledge: first, I provide a broadened definition of hydropolitics which moves beyond the macro-level to also include water politics as transpiring on meso and micro-levels; second, I contribute to the literature on citizenship and hydropolitics by giving an account of Madibeng hydropolitics paying attention to the experiences of Damonsville, Mothutlung and Mmakau residents; third, I present how the “new” South Africa is for some participants viewed as an exclusionary space as they withdraw from expression due to fear, coercion or duress, and coin the term disengaged citizenship to describe this social phenomenon.Ph.D. (Sociology

Gold, Palladium and Mesoporous Oxide-based Nanocatalysts for redox processes and sustainable catalysis : synthesis and catalytic evaluation

Abstract: Transition metals' exceptional ability and properties at the nanoscale level transcend their corresponding bulk metals in chemical transformation both in the laboratories and the industries. However, the nanoparticles are prone to particle growth and agglomeration at this nanoscale state, inhibiting their excellent performance and compromising their uniqueness. Hence, the stability of the particles presents a significant factor in governing their innovative attributes. Therefore, organic polymers, such as polyvinylpyrrolidone (PVP) and dendrimer, were considerably employed as soft templates to ensure stability and prevent the agglomeration of these nanoparticles in a homogeneous phase. These synthesized nanoparticles include AuPVP, PdPVP, AuPdPVP nanoparticles, and CuDENs. Although conventional homogeneous catalysts possess a vast tendency to enhance high conversion and product selectivity in chemical reactions, nevertheless, they present limiting phenomenon of recoverability, recyclability, and deactivation at high temperatures. Therefore, to circumvent these limitations, we fabricated metal nanoparticles through the dispersion of metals onto an insoluble and solid mesoporous silica and metal oxide support by adapting a dual templating approach, followed by a galvanic replacement protocol. In addition, inverse micelle, sol-gel, and wet impregnation methods were also employed to design ideal heterogeneous catalysts such as Cun@SiO2, Au@SiO2, Pd@SiO2, CoMMO, and MnMMO, which are capable of high operating procedures, easy recoverability, and reusability for oxidation and reduction reactions. Different analytical techniques were used to characterize and obtain the properties of these catalysts. These techniques include nitrogen sorption with Brunauer-Emmett-Teller (BET) and Barret-Joyner-Halenda (BJH) to examine the surface area, pore size, and pore volume distribution, high-resolution transmission electron microscopy (H-TEM) for internal morphologies, powder X-ray diffraction (p-XRD), for the diffraction patterns of the materials. While thermogravimetric analysis (TG) was performed to determine the sample’s thermal stability, Fourier transform infrared spectroscopy (FT-IR) identified the specific functional groups present. Scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX) obtained the surface morphologies and identification of metal composition. In addition, hydrogen-temperature programmed reduction (H2-TPR) was used to examine the reducibility of the catalyst...Ph.D. (Chemistry