Establishment of screening procedures for genetic disorders and risk factors in the South African Caucasian population

Please read the abstract in the section 00front of this documentDissertation (MSc (Chemical Pathology))--University of Pretoria, 2005.Chemical Pathologyunrestricte

In Vitro Medicinal Properties of Novel Compounds from Croton steenkampianus

The effect of infectious diseases on the population in the developing countries is of utmost concern. Malaria, tuberculosis (TB) and human immunodeficiency virus (HIV) are the three major infectious disease threats. They account for approximately half of the mortality caused by infectious diseases, which is almost half of the mortality in the developing countries. With no vaccine likely in the foreseeable future, drugs remain the best means of controlling infectious diseases. In the industrialized nations at the present time, some 50% of all prescribed drugs are derived or synthesized from natural products (animals, marine species, plants and micro-organisms). It has been estimated that plants are the most important source of medicine for more than 80% of the world’s population. As previous work on the leaves of Croton steenkampianus gave promising results and revealed that it still contained bioactive compounds that could be isolated, it was chosen for further work. The bioassay guided fractionation of the ethanol crude extract using silica and Sephadex column chromatography resulted in the isolation of six compounds: three flavoniods (quercetin, tamarixetin and eriodictyol), one new indane (1) (2,6-dimethyl-1-oxo-4 indanecarboxylic acid) and two new diterpenes (steenkrotin A (2) and steenkrotin B (3)) with novel skeletons. The structure of the compounds was determined using NMR, IR, UV, MS and X-ray crystallography. Ethanol crude extract, quercetin, steenkrotin A, steenkrotin B and the indane were tested against four strains of Plasmodium falciparum (D6, D10, Dd2 and W2). Quercetin showed good antiplasmodial activity against the D10 and Dd2 strains. The antiplasmodial activity of steenkrotin A and crude extract were moderate. The antimalarial activity of steenkrotin A in particular is promising, as it showed more activity against resistant strains. The indane, and steekrotin B were not active against the strains of P. falciparum used (IC50 > 10 μg/m). The IC50 of the compounds improved when they were combined with chloroquine. However, the IC50 of chloroquine was still the lowest. The compounds showed moderate bioactivity against Bacillus cereus and Escherichia coli. The three new compounds (1, 2 and 3) tested against Mycobacterium (H37Rv) were not active (IC50 > 10 μg/ml). The indane (1) showed anti-HIV activity at 50 μg/ml against reverse transcriptase. The antioxidant activity of the compounds tested ranged from weak to excellent (>280.00 μg/ml for compound 1 and 2 to 0.05 μg/ml for quercetin). The cytotoxicity of the compounds and extract were determined against Vero cells lines. Their IC50 values ranged from 34.0 to 305.9 ìg/ml, which is higher and better than that of chloroquine. The IC50 values obtained are: chloroquine (25.0), quercetin (33.6), steenkrotin A (35.0), ethanol extract (45.0), tamarixetin (53.8), indane (248.2) and steenkrotin B (305.9).Thesis (PhD)--University of Pretoria, 2009.Plant Scienceunrestricte

Gender pay gap in salary bands among employees in the formal sector of South Africa

ORIENTATION : The gender pay gap is a worldwide challenge that has persisted despite political will and interventions. Comparably qualified women performing similar work as men continue to earn less. There are conflicting views in the literature regarding the status of the gender pay gap. RESEARCH PURPOSE : The purpose of the study was to determine status of the gender pay gap among employees in the same salary band and to establish whether men and women receive similar pay for similar work in the study population. MOTIVATION FOR STUDY: The status of the gender pay gap would establish the progress made towards closing the gap and guide necessary adjustments to interventions. RESEARCH APPROACH/DESIGN AND METHOD : A quantitative analysis was conducted on the pay information of 217 902 employees collected in a survey from over 700 companies, across 10 job families and 6 industries. MAIN FINDINGS : Men’s pay was consistently higher than that of women in all salary bands except at the 75th and 95th percentile in sub-bands B-lower and B-upper and 25th percentile in sub-band E-upper. The gender pay gap ranged from 8% in band A to 27.1% in sub-band F-upper. The gaps observed in the salary bands were statistically significant (p < 0.0001) except in sub-band E-upper, F-lower and F-upper, indicating convergence towards similar pay for similar work at senior to top management levels. Women were under-represented in all salary bands with the lowest presence in band F, especially sub-band F-upper. Gender, race, job family and industry have a significant effect on income earned in the study sample. PRACTICAL/MANAGERIAL IMPLICATIONS : Government’s efforts seemed to have produced minimal results as women are represented in all job families, industries and salary bands. The pay of men and women in senior and top management levels was similar. However, more still needs to be done to achieve the 50% target representation of women in senior management and close the gap at all levels. CONTRIBUTION/VALUE-ADD : The number of women at management levels is still very low when compared to their male counterparts. However, the gender pay gap in senior to top management positions are converging towards similar pay for work of similar value.http://www.sajhrm.co.zaam2019Gordon Institute of Business Science (GIBS