Prostate specific membrane antigen (PSMA) was probed in breast carcinoma cell lines (MCF-7 and MD... more Prostate specific membrane antigen (PSMA) was probed in breast carcinoma cell lines (MCF-7 and MDA-MB-231). The expression was qualitatively and quantitatively compared to LNCaP cells, which are prostate carcinoma cells that are known to express PSMA at high levels. Confocal microscopy was used to qualitatively identify PSMA in the breast and prostate cancer cells. Flow cytometry was also applied in PSMA qualitative identification and also used as a semi-quantitative tool. Absolute quantitation was undertaken utilising the Enzyme-linked immunosorbent assay (ELISA). Cell enumeration was used as a indicator of relative viability and the assay utilised was the crystal violet assay.
Jeremiah S. Shelembe, Duncan Cromarty, Megan J. Bester, Amanda Minnaar, Kwaku G. Duodu Department... more Jeremiah S. Shelembe, Duncan Cromarty, Megan J. Bester, Amanda Minnaar, Kwaku G. Duodu Department of Food Science, Department of Pharmacology, Department of Anatomy, University of Pretoria, Pretoria, Lynnwood Road, Private bag X20, Hatfield, Pretoria 0002, South Africa; Department of Consumer Science, Faculty of Agriculture, University of Swaziland, Luyengo, Swaziland Correspondent: E-mail: gyebi.duodu@up.ac.za ; Fax: +27 (012) 42
It has been shown in a previous study that brown coal-derived potassium humate is safe and effect... more It has been shown in a previous study that brown coal-derived potassium humate is safe and effective in suppressing contact hypersensitivity in rats. In this study the efficacy of potassium humate on other types of inflammation was determined. Preparative TLC followed by mass spectroscopy was used in an attempt to fingerprint the product. The effects of potassium humate, at an
International Journal of Food Science Technology, 2012
ABSTRACT Freeze-dried aqueous phenolic extracts with possible application as natural antioxidant ... more ABSTRACT Freeze-dried aqueous phenolic extracts with possible application as natural antioxidant functional food ingredients were prepared from marama bean seed coats by extracting with water. Phenolic acids, flavonoids and proanthocyanidins in the extracts were characterised by HPLC/MS. The major flavonoids were the flavanols methyl (epi)afzelechin-3-O-gallate (40%) and methyl (epi)catechin-3-O-gallate (28%), and the major phenolic acid was gallic acid (10%). Proanthocyanidins in the extracts were predominantly prodelphinidins composed of epicatechin-3-O-gallate and epigallocatechin present as major terminal and extension units and epigallocatechin-3-O-gallate and epicatechin present as minor extension unit constituents. The polymer structure was found to be unique compared with other legumes because of the high percentage of galloylated units. Extracts showed a high DPPH free radical scavenging activity (707 μmol TE g−1), protective effect against AAPH-induced human red blood cell haemolysis and copper-catalysed human LDL oxidation suggesting that the extracts may have potential health benefits.
Docking and molecular dynanmics simulations using Autodock Vina and Gromacs were used to identify... more Docking and molecular dynanmics simulations using Autodock Vina and Gromacs were used to identify selective inhibitors of cancer-, osteoclastogenic-and malaria-associated proteins. Selective benzotriazepine in-hibitors of bromodomain 4 were identified and synthesized. The compounds show micromolar growth inhibition of several cancer cell lines, as well as potent inhibition of osteoclastogenesis without cytotoxicity against osteoclast progenators. Potent inhibitors of malaria cytochrome bc1 proteins were identified and synthesized. The most potent compound inhibited in vitro asexual malaria parasite growth to 50% of the control at a concentration of 64nM. The compound showed no activity against human HepG2 cells at 5uM. The present study will discuss how freely available docking and molecular dynamics tools are able to help researchers narrow down new, potent and selective pharmaceutically relevant compounds. HPC content Docking and molecular dynanmics simulations using Autodock Vina and Gromacs were used to identify selective inhibitors of cancer-, osteoclastogenic-and malaria-associated proteins. The present study will discuss how freely available docking and molecular dynamics tools are able to help researchers narrow down new, potent and selective pharmaceutically relevant compounds.
Southern African Journal of Infectious Diseases, 2015
Introduction: Teicoplanin is an effective treatment option against methicillin-resistant, Gram-po... more Introduction: Teicoplanin is an effective treatment option against methicillin-resistant, Gram-positive bacteria, like Staphylococcus aureus. It is a glycopeptide antibiotic, produced through microbial fermentation, a process resulting in variations in the N-acyl side chain. Concerns that these variations may affect the pharmacokinetic profile and the clinical efficacy of generic teicoplanin preparations have been raised. Method: To address this issue, a multi-centre observational study was conducted to evaluate steady-state peak and trough serum concentrations, and the serum bactericidal activity (SBA) and safety of a generic teicoplanin preparation in critically ill patients. Additionally, the composition of the generic teicoplanin was compared to that of the innovator drug to assess differences in the composition. Results: Following pre-determined loading and maintenance dose schedules, the mean peak and trough teicoplanin serum concentrations were 20.98 mg/l and 10.38 mg/l, respectively. A statistically significant association was observed between teicoplanin pharmacotherapy and increased ex vivo SBA. It was found using independent analysis that the composition of the generic teicoplanin preparation was similar to that of the innovator drug, and that both formulations met the European Pharmacopoeia specifications. Conclusion: The loading and maintenance schedules employed in this study were effective in establishing therapeutic serum teicoplanin concentrations in critically ill patients. Evidence of bactericidal activity measured in patients’ ex vivo serum samples, following treatment with the generic preparation, supports this finding.
The following study evaluates the overt toxic potential of carprofen (CRP), flunixin (FXN) and ph... more The following study evaluates the overt toxic potential of carprofen (CRP), flunixin (FXN) and phenylbutazone (PBZ) in Old world vultures in relation to historic toxicity data for diclofenac and ketoprofen, with the Cape vulture (Gyps coprotheres) being the indicator species. The toxic potential of a single oral dose of CRP (11.5 mg/kg), FXN (1 mg/kg),PBZ (1.7 mg/kg) or water was evaluated by means of a four-way parallel study (n = 2), as means of ascertaining if these drugs were as toxic as diclofenac in the vulture. No unscheduled deaths or pathological lesions were noted following exposure. Clinical signs of lethargy and depression were, however, noted in one CRP, two FXN and one PBZ treated birds. Mild reversible inhibition of UA excretion was evident in all three groups, although UA remained within the population reference interval in contrast to the effects previously described for diclofenac and ketoprofen. All treatment groups had a drug concentration responsive increase in alanine transferase activity. CRP, FXN and PBZ were characterised by a maximum plasma concentration (Cmax) of 1051.8 ± 620.7 ng/ml, 335.9 ± 36.3 ng/ml and 11150 ± 2474.9 ng/ml at 4 ± 4.3, 0.45 ± 0.02 and 5.3 ± 5.2 hours (Tmax) respectively and a half-life of elimination of 13.3 ±5, 1.8±1 and 18.7 ±11.4 hours respectively. While we could not demonstrate a lethal effect of the tested substances, the presence of toxic clinical signs, clinical pathological changes and/or long half-lives of elimination suggests that all three drugs have a potential for toxicity in a larger population or on repeat administration. In conclusion while the studied substances were not as overtly toxic as diclofenac, they are of safety concern.
To align predicted and measured CYP2C19 phenotype in a South African cohort. Genotyping of CYP2C1... more To align predicted and measured CYP2C19 phenotype in a South African cohort. Genotyping of CYP2C19*2, *3, *9, *15, *17, *27 and *28 was performed using PCR-RFLP, and an activity score (AS) system was used to predict phenotype. True phenotype was measured using plasma concentrations of omeprazole and its metabolite 5'-hydroxyomperazole. Partial genotype-phenotype discrepancies were reported, and an adapted AS system was developed, which showed a marked improvement in phenotype prediction. Results highlight the need for a more comprehensive CYP2C19 genotyping approach to improve prediction of omeprazole metabolism. Evidence for the utility of a CYP2C19 AS system is provided, for which the accuracy can be further improved by means of comprehensive genotyping and substrate-specific modification.
Prostate specific membrane antigen (PSMA) was probed in breast carcinoma cell lines (MCF-7 and MD... more Prostate specific membrane antigen (PSMA) was probed in breast carcinoma cell lines (MCF-7 and MDA-MB-231). The expression was qualitatively and quantitatively compared to LNCaP cells, which are prostate carcinoma cells that are known to express PSMA at high levels. Confocal microscopy was used to qualitatively identify PSMA in the breast and prostate cancer cells. Flow cytometry was also applied in PSMA qualitative identification and also used as a semi-quantitative tool. Absolute quantitation was undertaken utilising the Enzyme-linked immunosorbent assay (ELISA). Cell enumeration was used as a indicator of relative viability and the assay utilised was the crystal violet assay.
Jeremiah S. Shelembe, Duncan Cromarty, Megan J. Bester, Amanda Minnaar, Kwaku G. Duodu Department... more Jeremiah S. Shelembe, Duncan Cromarty, Megan J. Bester, Amanda Minnaar, Kwaku G. Duodu Department of Food Science, Department of Pharmacology, Department of Anatomy, University of Pretoria, Pretoria, Lynnwood Road, Private bag X20, Hatfield, Pretoria 0002, South Africa; Department of Consumer Science, Faculty of Agriculture, University of Swaziland, Luyengo, Swaziland Correspondent: E-mail: gyebi.duodu@up.ac.za ; Fax: +27 (012) 42
It has been shown in a previous study that brown coal-derived potassium humate is safe and effect... more It has been shown in a previous study that brown coal-derived potassium humate is safe and effective in suppressing contact hypersensitivity in rats. In this study the efficacy of potassium humate on other types of inflammation was determined. Preparative TLC followed by mass spectroscopy was used in an attempt to fingerprint the product. The effects of potassium humate, at an
International Journal of Food Science Technology, 2012
ABSTRACT Freeze-dried aqueous phenolic extracts with possible application as natural antioxidant ... more ABSTRACT Freeze-dried aqueous phenolic extracts with possible application as natural antioxidant functional food ingredients were prepared from marama bean seed coats by extracting with water. Phenolic acids, flavonoids and proanthocyanidins in the extracts were characterised by HPLC/MS. The major flavonoids were the flavanols methyl (epi)afzelechin-3-O-gallate (40%) and methyl (epi)catechin-3-O-gallate (28%), and the major phenolic acid was gallic acid (10%). Proanthocyanidins in the extracts were predominantly prodelphinidins composed of epicatechin-3-O-gallate and epigallocatechin present as major terminal and extension units and epigallocatechin-3-O-gallate and epicatechin present as minor extension unit constituents. The polymer structure was found to be unique compared with other legumes because of the high percentage of galloylated units. Extracts showed a high DPPH free radical scavenging activity (707 μmol TE g−1), protective effect against AAPH-induced human red blood cell haemolysis and copper-catalysed human LDL oxidation suggesting that the extracts may have potential health benefits.
Docking and molecular dynanmics simulations using Autodock Vina and Gromacs were used to identify... more Docking and molecular dynanmics simulations using Autodock Vina and Gromacs were used to identify selective inhibitors of cancer-, osteoclastogenic-and malaria-associated proteins. Selective benzotriazepine in-hibitors of bromodomain 4 were identified and synthesized. The compounds show micromolar growth inhibition of several cancer cell lines, as well as potent inhibition of osteoclastogenesis without cytotoxicity against osteoclast progenators. Potent inhibitors of malaria cytochrome bc1 proteins were identified and synthesized. The most potent compound inhibited in vitro asexual malaria parasite growth to 50% of the control at a concentration of 64nM. The compound showed no activity against human HepG2 cells at 5uM. The present study will discuss how freely available docking and molecular dynamics tools are able to help researchers narrow down new, potent and selective pharmaceutically relevant compounds. HPC content Docking and molecular dynanmics simulations using Autodock Vina and Gromacs were used to identify selective inhibitors of cancer-, osteoclastogenic-and malaria-associated proteins. The present study will discuss how freely available docking and molecular dynamics tools are able to help researchers narrow down new, potent and selective pharmaceutically relevant compounds.
Southern African Journal of Infectious Diseases, 2015
Introduction: Teicoplanin is an effective treatment option against methicillin-resistant, Gram-po... more Introduction: Teicoplanin is an effective treatment option against methicillin-resistant, Gram-positive bacteria, like Staphylococcus aureus. It is a glycopeptide antibiotic, produced through microbial fermentation, a process resulting in variations in the N-acyl side chain. Concerns that these variations may affect the pharmacokinetic profile and the clinical efficacy of generic teicoplanin preparations have been raised. Method: To address this issue, a multi-centre observational study was conducted to evaluate steady-state peak and trough serum concentrations, and the serum bactericidal activity (SBA) and safety of a generic teicoplanin preparation in critically ill patients. Additionally, the composition of the generic teicoplanin was compared to that of the innovator drug to assess differences in the composition. Results: Following pre-determined loading and maintenance dose schedules, the mean peak and trough teicoplanin serum concentrations were 20.98 mg/l and 10.38 mg/l, respectively. A statistically significant association was observed between teicoplanin pharmacotherapy and increased ex vivo SBA. It was found using independent analysis that the composition of the generic teicoplanin preparation was similar to that of the innovator drug, and that both formulations met the European Pharmacopoeia specifications. Conclusion: The loading and maintenance schedules employed in this study were effective in establishing therapeutic serum teicoplanin concentrations in critically ill patients. Evidence of bactericidal activity measured in patients’ ex vivo serum samples, following treatment with the generic preparation, supports this finding.
The following study evaluates the overt toxic potential of carprofen (CRP), flunixin (FXN) and ph... more The following study evaluates the overt toxic potential of carprofen (CRP), flunixin (FXN) and phenylbutazone (PBZ) in Old world vultures in relation to historic toxicity data for diclofenac and ketoprofen, with the Cape vulture (Gyps coprotheres) being the indicator species. The toxic potential of a single oral dose of CRP (11.5 mg/kg), FXN (1 mg/kg),PBZ (1.7 mg/kg) or water was evaluated by means of a four-way parallel study (n = 2), as means of ascertaining if these drugs were as toxic as diclofenac in the vulture. No unscheduled deaths or pathological lesions were noted following exposure. Clinical signs of lethargy and depression were, however, noted in one CRP, two FXN and one PBZ treated birds. Mild reversible inhibition of UA excretion was evident in all three groups, although UA remained within the population reference interval in contrast to the effects previously described for diclofenac and ketoprofen. All treatment groups had a drug concentration responsive increase in alanine transferase activity. CRP, FXN and PBZ were characterised by a maximum plasma concentration (Cmax) of 1051.8 ± 620.7 ng/ml, 335.9 ± 36.3 ng/ml and 11150 ± 2474.9 ng/ml at 4 ± 4.3, 0.45 ± 0.02 and 5.3 ± 5.2 hours (Tmax) respectively and a half-life of elimination of 13.3 ±5, 1.8±1 and 18.7 ±11.4 hours respectively. While we could not demonstrate a lethal effect of the tested substances, the presence of toxic clinical signs, clinical pathological changes and/or long half-lives of elimination suggests that all three drugs have a potential for toxicity in a larger population or on repeat administration. In conclusion while the studied substances were not as overtly toxic as diclofenac, they are of safety concern.
To align predicted and measured CYP2C19 phenotype in a South African cohort. Genotyping of CYP2C1... more To align predicted and measured CYP2C19 phenotype in a South African cohort. Genotyping of CYP2C19*2, *3, *9, *15, *17, *27 and *28 was performed using PCR-RFLP, and an activity score (AS) system was used to predict phenotype. True phenotype was measured using plasma concentrations of omeprazole and its metabolite 5'-hydroxyomperazole. Partial genotype-phenotype discrepancies were reported, and an adapted AS system was developed, which showed a marked improvement in phenotype prediction. Results highlight the need for a more comprehensive CYP2C19 genotyping approach to improve prediction of omeprazole metabolism. Evidence for the utility of a CYP2C19 AS system is provided, for which the accuracy can be further improved by means of comprehensive genotyping and substrate-specific modification.
Uploads