The current drugs available in the market are not effective due to growing numbers of resistance ... more The current drugs available in the market are not effective due to growing numbers of resistance to the causative agent of malaria. There are variousPlasmodiumparasites, of whichPlasmodium falciparumis the main cause of morbidity and mortality reported worldwide. Therefore, there is an urgent need to come up with an innovative and effective treatment for this disease. Polyamines play a major role in the parasite’s well-being and growth, while heat shock proteins keep the proteomics of the parasite in good shape. In this study,In Silicoanalysis of the interaction between putrescine, spermidine, spermine, and heat shock proteins was carried out to establish the binding site for drug discovery. Computational tools such as Bioedit, PROCHECK, KNIME Hub, and Schrodinger were used. The results revealed interactions between polyamines and heat shock proteins with glutamine and aspartic acid being common amino acids where interaction occurs between the chaperones and polyamines. MD shows a s...
The current drugs available in the market are not effective due to growing numbers of resistance ... more The current drugs available in the market are not effective due to growing numbers of resistance to the causative agent of malaria. There are various Plasmodium parasites, of which Plasmodium falciparum is the main cause of morbidity and mortality reported worldwide. Therefore, there is an urgent need to come up with an innovative and effective treatment for this disease. Polyamines play a major role in the parasite’s well-being and growth, while heat shock proteins keep the proteomics of the parasite in good shape. In this study, an in silico analysis of the interaction between putrescine, spermidine, spermine, and heat shock proteins was carried out to establish the binding site for drug discovery. Computational tools such as Bioedit, PROCHECK, KNIME Hub, and Schrodinger were used. The results revealed interactions between polyamines and heat shock proteins with glutamine and aspartic acid being common amino acids where interaction occurs between the chaperones and polyamines. Mol...
Iranian Journal of Pharmaceutical Research : IJPR, 2017
We evaluated the in-vitro antiproliferative and apoptotic potential of the ethyl acetate extract ... more We evaluated the in-vitro antiproliferative and apoptotic potential of the ethyl acetate extract (EAE) of Peltophorum africanum, a member of the family Fabaceae (Sond) in order to validate its pharmacological use. Antiproliferation of human breast (MCF-7), colon (HT-29) and cervical (HeLa) cancer cell lines by EAE was investigated using the Cell Titer-Blue viability assay and the mechanism of action delineated using the Nucleic Acid and Protein Purification Nucleospin® Tissue Kit, Scanning Electron Microscope (SEM), propidium iodide (PI) and acridine orange (AO) double-staining techniques. We observed a significant reduction in cell viability of the MCF-7 cells from 100% (untreated) to 54.33 ± 1.84% after 72 h of treatment with 5 µg/mL of EAE (P. value < 0.05). Internucleosomal DNA of MCF-7, HT-29 and HeLa cells was randomly fragmented into an uninterrupted spectrum of sizes, complemented by the intercalation of nucleic acid-specific fluorochromes by PI and AO spotting two phases...
Helicobacter pylori (H. pylori) is a microaerophilic motile curve rod that inhabits the gastric m... more Helicobacter pylori (H. pylori) is a microaerophilic motile curve rod that inhabits the gastric mucosa of the human stomach. The organism chronically infects billions of people worldwide and is one of the most genetically diverse of bacterial species. Infection with the bacterium which leads to chronic gastritis, peptic ulceration, gastric cancers and gastric malt lymphoma has been reported to follow a pattern linked to geographic and socio-demographic factors. Studies have documented a higher prevalence in Africa than elsewhere although the pathological outcomes do not correlate with infection. H. pylori transmission pathways are still vague, but the risks of transmission include precarious hygiene standards, over-crowding and contaminated environment and water sources amongst others. The possible routes of transmission include oral-oral, faecal-oral and person- to -person, either with or without transitional transmission steps during episodes of diarrhoea or gastro-oral contact in...
South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, 2010
OBJECTIVES Helicobacter pylori-associated infection is common in South Africa, as in other develo... more OBJECTIVES Helicobacter pylori-associated infection is common in South Africa, as in other developing countries. Antibiotic resistance is recognised as a major cause of treatment failure. We studied the susceptibility and resistance patterns of H. pylori to guide empiric treatment and prevent the emergence of resistance. METHODS Two hundred H. pylori strains obtained from gastric biopsies of patients presenting with gastric-related morbidities attending Livingstone Hospital, Port Elizabeth, were evaluated for their susceptibility to seven antibiotics - metronidazole, clarithromycin, tetracycline, amoxicillin, gentamicin, ciprofloxacin and erythromycin. H. pylori was isolated following standard microbiology procedures, and susceptibility determined using the Kirby-Bauer disc diffusion and agar dilution methods. Comparisons of antimicrobial resistance rates with sex of the patients were determined using the chi-square test; a p-value of <0.05 was considered significant. RESULTS Mar...
Reviews of Environmental Contamination and Toxicology, 2018
4-tert-Octylphenol is a degradation product of non-ionic surfactants alkylphenol polyethoxylates ... more 4-tert-Octylphenol is a degradation product of non-ionic surfactants alkylphenol polyethoxylates as well as raw material for a number of industrial applications. It is a multimedia compound having been detected in all environmental compartments such as indoor air and surface waters. The pollutant is biodegradable, but certain degradation products are more toxic than the parent compound. Newer removal techniques from environmental waters have been presented, but they still require development for large-scale applications. Wastewater treatment by plant enzymes such as peroxidases offers promise in total removal of 4-tert-octylphenol leaving less toxic degradation products. The pollutant's endocrine interference has been well reported but more in oestrogens than in any other signalling pathways through which it is believed to exert toxicity on human and wildlife. In this paper we carried out a review of the activities of this pollutant in environmental waters, endocrine interference and relevance to its toxicities and concluded that inadequate knowledge of its endocrine activities impedes understanding of its toxicity which may frustrate current efforts at ridding the compound from the environment.
We assessed thein vitroantimicrobial activity ofPeltophorum africanumby means of the agar well an... more We assessed thein vitroantimicrobial activity ofPeltophorum africanumby means of the agar well and macrodilution methods. The toxicity on a normal human liver cell (Chang liver cell) was determined using the CellTiter-Blue cell viability assay, and the compounds contained in the fractions were identified using GC-MS. Zone diameter of inhibition of the extract ranged from12.5±0.7 to 32 ± 2.8 mm for bacteria and from 7.5 ± 0.7 to 26.4 ± 3.4 mm for yeast. Marked activity of the extract was observed againstPlesiomonas shigelloidesATCC 51903, with MIC and MLC values of 0.15625 and 0.3125 mg/mL, respectively. The extract was both bactericidal (MICindex≤2) and bacteriostatic/fungistatic (MICindex>2) in activity. Lethal dose at 50 (LD50) showed82.64±1.40degree of toxicity at 24 hrs, and 95 percentile of cell death dose activity ranged from log3.12±0.01 to 4.59±0.03. The activity of the eight fractions tested ranged from1.0±0.5 to 3.7±1.6 mg/mL (IC50) and from 2.1±0.8 to 6.25±...
The International Journal of Biochemistry & Cell Biology, 2002
Calcium-activated neutral proteinases (CANPs) and their endogenous specific inhibitor calpastatin... more Calcium-activated neutral proteinases (CANPs) and their endogenous specific inhibitor calpastatin are found in a wide variety of vertebrate and invertebrate tissues. The CANPs are cysteine proteinases that have an absolute requirement for Ca2+ for activity. μ-Calpain and calpastatin were purified by successive chromatographic steps on Toyopearl-Super Q 650S and Pharmacia Mono Q HR 5/5 columns. The enzyme has a Mr
The International Journal of Biochemistry & Cell Biology, 1999
Ostrich carboxypeptidases A and B were recently purified and characterized. The aim of this study... more Ostrich carboxypeptidases A and B were recently purified and characterized. The aim of this study was to isolate and purify, and partially characterize in terms of molecular weight, pI, amino acid composition and N-terminal sequencing, the precursor forms of carboxypeptidases from the ostrich pancreas.Inhibition studies with soybean trypsin inhibitor and activation studies with three proteases (bovine trypsin, bovine chymotrypsin and
The current drugs available in the market are not effective due to growing numbers of resistance ... more The current drugs available in the market are not effective due to growing numbers of resistance to the causative agent of malaria. There are variousPlasmodiumparasites, of whichPlasmodium falciparumis the main cause of morbidity and mortality reported worldwide. Therefore, there is an urgent need to come up with an innovative and effective treatment for this disease. Polyamines play a major role in the parasite’s well-being and growth, while heat shock proteins keep the proteomics of the parasite in good shape. In this study,In Silicoanalysis of the interaction between putrescine, spermidine, spermine, and heat shock proteins was carried out to establish the binding site for drug discovery. Computational tools such as Bioedit, PROCHECK, KNIME Hub, and Schrodinger were used. The results revealed interactions between polyamines and heat shock proteins with glutamine and aspartic acid being common amino acids where interaction occurs between the chaperones and polyamines. MD shows a s...
The current drugs available in the market are not effective due to growing numbers of resistance ... more The current drugs available in the market are not effective due to growing numbers of resistance to the causative agent of malaria. There are various Plasmodium parasites, of which Plasmodium falciparum is the main cause of morbidity and mortality reported worldwide. Therefore, there is an urgent need to come up with an innovative and effective treatment for this disease. Polyamines play a major role in the parasite’s well-being and growth, while heat shock proteins keep the proteomics of the parasite in good shape. In this study, an in silico analysis of the interaction between putrescine, spermidine, spermine, and heat shock proteins was carried out to establish the binding site for drug discovery. Computational tools such as Bioedit, PROCHECK, KNIME Hub, and Schrodinger were used. The results revealed interactions between polyamines and heat shock proteins with glutamine and aspartic acid being common amino acids where interaction occurs between the chaperones and polyamines. Mol...
Iranian Journal of Pharmaceutical Research : IJPR, 2017
We evaluated the in-vitro antiproliferative and apoptotic potential of the ethyl acetate extract ... more We evaluated the in-vitro antiproliferative and apoptotic potential of the ethyl acetate extract (EAE) of Peltophorum africanum, a member of the family Fabaceae (Sond) in order to validate its pharmacological use. Antiproliferation of human breast (MCF-7), colon (HT-29) and cervical (HeLa) cancer cell lines by EAE was investigated using the Cell Titer-Blue viability assay and the mechanism of action delineated using the Nucleic Acid and Protein Purification Nucleospin® Tissue Kit, Scanning Electron Microscope (SEM), propidium iodide (PI) and acridine orange (AO) double-staining techniques. We observed a significant reduction in cell viability of the MCF-7 cells from 100% (untreated) to 54.33 ± 1.84% after 72 h of treatment with 5 µg/mL of EAE (P. value < 0.05). Internucleosomal DNA of MCF-7, HT-29 and HeLa cells was randomly fragmented into an uninterrupted spectrum of sizes, complemented by the intercalation of nucleic acid-specific fluorochromes by PI and AO spotting two phases...
Helicobacter pylori (H. pylori) is a microaerophilic motile curve rod that inhabits the gastric m... more Helicobacter pylori (H. pylori) is a microaerophilic motile curve rod that inhabits the gastric mucosa of the human stomach. The organism chronically infects billions of people worldwide and is one of the most genetically diverse of bacterial species. Infection with the bacterium which leads to chronic gastritis, peptic ulceration, gastric cancers and gastric malt lymphoma has been reported to follow a pattern linked to geographic and socio-demographic factors. Studies have documented a higher prevalence in Africa than elsewhere although the pathological outcomes do not correlate with infection. H. pylori transmission pathways are still vague, but the risks of transmission include precarious hygiene standards, over-crowding and contaminated environment and water sources amongst others. The possible routes of transmission include oral-oral, faecal-oral and person- to -person, either with or without transitional transmission steps during episodes of diarrhoea or gastro-oral contact in...
South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, 2010
OBJECTIVES Helicobacter pylori-associated infection is common in South Africa, as in other develo... more OBJECTIVES Helicobacter pylori-associated infection is common in South Africa, as in other developing countries. Antibiotic resistance is recognised as a major cause of treatment failure. We studied the susceptibility and resistance patterns of H. pylori to guide empiric treatment and prevent the emergence of resistance. METHODS Two hundred H. pylori strains obtained from gastric biopsies of patients presenting with gastric-related morbidities attending Livingstone Hospital, Port Elizabeth, were evaluated for their susceptibility to seven antibiotics - metronidazole, clarithromycin, tetracycline, amoxicillin, gentamicin, ciprofloxacin and erythromycin. H. pylori was isolated following standard microbiology procedures, and susceptibility determined using the Kirby-Bauer disc diffusion and agar dilution methods. Comparisons of antimicrobial resistance rates with sex of the patients were determined using the chi-square test; a p-value of <0.05 was considered significant. RESULTS Mar...
Reviews of Environmental Contamination and Toxicology, 2018
4-tert-Octylphenol is a degradation product of non-ionic surfactants alkylphenol polyethoxylates ... more 4-tert-Octylphenol is a degradation product of non-ionic surfactants alkylphenol polyethoxylates as well as raw material for a number of industrial applications. It is a multimedia compound having been detected in all environmental compartments such as indoor air and surface waters. The pollutant is biodegradable, but certain degradation products are more toxic than the parent compound. Newer removal techniques from environmental waters have been presented, but they still require development for large-scale applications. Wastewater treatment by plant enzymes such as peroxidases offers promise in total removal of 4-tert-octylphenol leaving less toxic degradation products. The pollutant's endocrine interference has been well reported but more in oestrogens than in any other signalling pathways through which it is believed to exert toxicity on human and wildlife. In this paper we carried out a review of the activities of this pollutant in environmental waters, endocrine interference and relevance to its toxicities and concluded that inadequate knowledge of its endocrine activities impedes understanding of its toxicity which may frustrate current efforts at ridding the compound from the environment.
We assessed thein vitroantimicrobial activity ofPeltophorum africanumby means of the agar well an... more We assessed thein vitroantimicrobial activity ofPeltophorum africanumby means of the agar well and macrodilution methods. The toxicity on a normal human liver cell (Chang liver cell) was determined using the CellTiter-Blue cell viability assay, and the compounds contained in the fractions were identified using GC-MS. Zone diameter of inhibition of the extract ranged from12.5±0.7 to 32 ± 2.8 mm for bacteria and from 7.5 ± 0.7 to 26.4 ± 3.4 mm for yeast. Marked activity of the extract was observed againstPlesiomonas shigelloidesATCC 51903, with MIC and MLC values of 0.15625 and 0.3125 mg/mL, respectively. The extract was both bactericidal (MICindex≤2) and bacteriostatic/fungistatic (MICindex>2) in activity. Lethal dose at 50 (LD50) showed82.64±1.40degree of toxicity at 24 hrs, and 95 percentile of cell death dose activity ranged from log3.12±0.01 to 4.59±0.03. The activity of the eight fractions tested ranged from1.0±0.5 to 3.7±1.6 mg/mL (IC50) and from 2.1±0.8 to 6.25±...
The International Journal of Biochemistry & Cell Biology, 2002
Calcium-activated neutral proteinases (CANPs) and their endogenous specific inhibitor calpastatin... more Calcium-activated neutral proteinases (CANPs) and their endogenous specific inhibitor calpastatin are found in a wide variety of vertebrate and invertebrate tissues. The CANPs are cysteine proteinases that have an absolute requirement for Ca2+ for activity. μ-Calpain and calpastatin were purified by successive chromatographic steps on Toyopearl-Super Q 650S and Pharmacia Mono Q HR 5/5 columns. The enzyme has a Mr
The International Journal of Biochemistry & Cell Biology, 1999
Ostrich carboxypeptidases A and B were recently purified and characterized. The aim of this study... more Ostrich carboxypeptidases A and B were recently purified and characterized. The aim of this study was to isolate and purify, and partially characterize in terms of molecular weight, pI, amino acid composition and N-terminal sequencing, the precursor forms of carboxypeptidases from the ostrich pancreas.Inhibition studies with soybean trypsin inhibitor and activation studies with three proteases (bovine trypsin, bovine chymotrypsin and
Uploads
Papers by Noxolo Mkwetshana