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J PROFMULAAFRANCIS. "The effects of Corticosteroids on Neurotransmitter metabolism on the rat CNS.MSc thesis University of Nairobi.". In: East Afr Med J. 1996 Feb;73(2):88-90. Springerlink; 1986. Abstract

In a bid to determine the HIV-1 subtype variants in transmission in Nairobi and its possible association with clinical status, we screened 207 confirmed HIV-1 positive patients visiting HIV/AIDS laboratory at the Virus Research Centre in Nairobi between January and March 1994. We used a selfmade ELISA obtained from an established panel of HIV-1 V3 loop peptides (ANRS, France) and derived from seven isolates: MN, HXB2, SC, Z6, Z2, ELI and CDC4. Test samples were obtained from 95 blood donors and medical examination attendees, 57 patients with chronic diarrhoea, 31 confirmed pulmonary tuberculosis, 16 with pneumonia and 12 herpes zoster. Out of the total, 21.5% had antibodies against the MN strain, 19.1% had against the Z2 strain while reaction against the HXB2 strain was observed in 17.2%. SC, CDC4, Z6 and ELI had prevalences of 11.5%, 6.2%, 5.3% and 3.8% respectively. Fifteen per cent of the tested sera showed no reaction to any of the used peptides. Strong and significant associations were observed between the total number of strains a sample react to and the clinical state. We infer that both the North American consensus strains (MN and HXB2) and the African isolates (Z2 and Z6) are predominant in Nairobi. The correlation between antibody reactivity and clinical state is an interesting observation that necessitates an expanded study and, the use of strain specific peptides maybe a sensitive and easier method for use for molecular epidemiological purposes. PIP: During January-March 1994, in Nairobi, Kenya, the sera of pre-university students, suspected AIDS/advanced HIV-infection cases, and blood donors were screened for HIV-1 antibodies at the Virus Research Centre. All confirmed HIV-1 positive samples were categorized according to the patient's clinical status. A self-made ELISA was obtained from an established panel of HIV-1 V3 loop peptides and derived from seven isolates (MN and HXB2 [North American strains], SC, CDC4, Z2 and Z6 [African strains], and ELI). The sera of the 22 confirmed HIV-1 negative students were used as negative controls. There were 207 confirmed HIV-1 cases (95 blood donors and 112 suspected AIDS/advanced HIV-infection cases). 64 (31%) and 112 (54%) samples reacted to at least 3 strains and no more than 2 strains, respectively. The remaining 31 (15%) samples did not react to any of the 7 peptide strains. Samples with CD4 cell counts greater than 500 x 1 million reacted significantly to more peptide strains than those with CD4 counts below 200 x 1 million (88% vs. 7%). Reactivity to specific strains were 21.5% for MN, 19.1% for Z2, 17.2% for HXB2, 11.5% for SC, 6.2% for CDC 4, 5.5% for Z6, and 3.8% for ELI. Anti-HXB2 antibodies were more common in blood donors than suspected AIDS/advanced HIV-infection cases (22% vs. 13%). AIDS/advanced HIV-infection cases were more likely to have no antibodies than blood donors (21% vs. 7%). A significant association existed between the number of peptide strains a patient could react to and the clinical state (p 0.01). Specifically, 77% of samples with no V3 antibodies to the seven strains had AIDS or advanced HIV infection while 55% of those which had cross reactivity with three or more strains were asymptomatic. Further research is needed to better understand this correlation. These findings suggest that use of strain specific peptides may be a sensitive and easier method for use for molecular epidemiological purposes.

J PROFMULAAFRANCIS. "Enzymatic oil extraction and positional analysis of ω-3 fatty acids in Nile perch and salmon heads. Process Biochemistry.". In: Eur. J. Lipid Sci. Technol. 2011. Wiley; 2010. Abstract
PUFA from oil extracted from Nile perch viscera were enriched by selective enzymatic esterification ofthe free fatty acids (FFA) or by hydrolysis of ethyl esters of the fatty acids from the oil (FA-EE).Quantitative analysis was performed using RP-HPLC coupled to an evaporative light scattering detector(RP-HPLC-ELSD). The lipase from Thermomyces lanuginosus discriminated against docosahexaenoicacid (DHA) most, resulting in the highest DHA/DHA-EE enrichment while lipase from Pseudomonascepacia discriminated against eicosapentaenoic acid (EPA) most, resulting in the highest EPA/EPA-EEenrichment. The lipases discriminated between DHA and EPA with a higher selectivity when present asethyl esters (EE) than when in FFA form. Thus when DHA/EPA were enriched to the same levelduring esterification and hydrolysis reactions, the DHA-EE/EPA-EE recoveries were higher than thoseof DHA/EPA-FFA. In reactions catalysed by lipase from T. lanuginosus, at 26 mol% DHA/DHA-EE,DHA recovery was 76% while that of DHA-EE was 84%. In reactions catalysed by lipase fromP. cepacia, at 11 mol% EPA/EPA-EE, EPA recovery was 79% while that of EPA-EE was 92%. Bothesterification of FFA and hydrolysis of FA-EE were more effective for enriching PUFA compared tohydrolysis of the natural oil and are thus attractive process alternatives for the production of productshighly enriched in DHA and/or EPA. When there is only one fatty acid residue in each substratemolecule, the full fatty acid selectivity of the lipase can be expressed, which is not the case withtriglycerides as substrates.
J PROFMULAAFRANCIS. "The effects of Cortisone on GABA metabolism on the rat hypothalamus and hippocampus. MSc Thesis Donestsk State University.". In: East Afr Med J. 1996 Feb;73(2):88-90. Springerlink; 1983. Abstract

In a bid to determine the HIV-1 subtype variants in transmission in Nairobi and its possible association with clinical status, we screened 207 confirmed HIV-1 positive patients visiting HIV/AIDS laboratory at the Virus Research Centre in Nairobi between January and March 1994. We used a selfmade ELISA obtained from an established panel of HIV-1 V3 loop peptides (ANRS, France) and derived from seven isolates: MN, HXB2, SC, Z6, Z2, ELI and CDC4. Test samples were obtained from 95 blood donors and medical examination attendees, 57 patients with chronic diarrhoea, 31 confirmed pulmonary tuberculosis, 16 with pneumonia and 12 herpes zoster. Out of the total, 21.5% had antibodies against the MN strain, 19.1% had against the Z2 strain while reaction against the HXB2 strain was observed in 17.2%. SC, CDC4, Z6 and ELI had prevalences of 11.5%, 6.2%, 5.3% and 3.8% respectively. Fifteen per cent of the tested sera showed no reaction to any of the used peptides. Strong and significant associations were observed between the total number of strains a sample react to and the clinical state. We infer that both the North American consensus strains (MN and HXB2) and the African isolates (Z2 and Z6) are predominant in Nairobi. The correlation between antibody reactivity and clinical state is an interesting observation that necessitates an expanded study and, the use of strain specific peptides maybe a sensitive and easier method for use for molecular epidemiological purposes. PIP: During January-March 1994, in Nairobi, Kenya, the sera of pre-university students, suspected AIDS/advanced HIV-infection cases, and blood donors were screened for HIV-1 antibodies at the Virus Research Centre. All confirmed HIV-1 positive samples were categorized according to the patient's clinical status. A self-made ELISA was obtained from an established panel of HIV-1 V3 loop peptides and derived from seven isolates (MN and HXB2 [North American strains], SC, CDC4, Z2 and Z6 [African strains], and ELI). The sera of the 22 confirmed HIV-1 negative students were used as negative controls. There were 207 confirmed HIV-1 cases (95 blood donors and 112 suspected AIDS/advanced HIV-infection cases). 64 (31%) and 112 (54%) samples reacted to at least 3 strains and no more than 2 strains, respectively. The remaining 31 (15%) samples did not react to any of the 7 peptide strains. Samples with CD4 cell counts greater than 500 x 1 million reacted significantly to more peptide strains than those with CD4 counts below 200 x 1 million (88% vs. 7%). Reactivity to specific strains were 21.5% for MN, 19.1% for Z2, 17.2% for HXB2, 11.5% for SC, 6.2% for CDC 4, 5.5% for Z6, and 3.8% for ELI. Anti-HXB2 antibodies were more common in blood donors than suspected AIDS/advanced HIV-infection cases (22% vs. 13%). AIDS/advanced HIV-infection cases were more likely to have no antibodies than blood donors (21% vs. 7%). A significant association existed between the number of peptide strains a patient could react to and the clinical state (p 0.01). Specifically, 77% of samples with no V3 antibodies to the seven strains had AIDS or advanced HIV infection while 55% of those which had cross reactivity with three or more strains were asymptomatic. Further research is needed to better understand this correlation. These findings suggest that use of strain specific peptides may be a sensitive and easier method for use for molecular epidemiological purposes.

J PROFMULAAFRANCIS. "Enzymatic enrichment of omega-3 polyunsaturated fatty acids in Nile perch (Lates niloticus) viscera oil.". In: European Journal of Lipid Science and Technology. Volume 112, Issue 9, pages 977. Wiley; 2010. Abstract
Oil was extracted from fatty material obtained from Nile perch viscera using the protease Protex 30L. Enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the glyceride fraction was carried out by hydrolysis of extracted oils with lipases from Candida rugosa, Thermomyces lanuginosus and Pseudomonas cepacia. The unusual fatty acid distribution of the oil influenced the apparent lipase specificity to a large extent. In the unhydrolysed oil, only 16% of EPA was in sn-2 position while 51% of palmitic acid was located in this position of the triacylglycerol (TAG) molecules. Non-regioselective lipase from C. rugosa was the most effective in combined enrichment of both EPA and DHA. This was partly because it was able to hydrolyse off palmitic acid from the sn-2 position, which 1-, 3-specific lipases were unable to do. Hydrolysis with C. rugosa lipase enriched EPA from 3 to 6 mol% and DHA from 9 to 23 mol%, with recoveries of 42 and 55%, respectively. The 1-, 3-specific lipase from T. lanuginosus was ineffective in enriching EPA, but gave best DHA enrichment, 38 mol% with a recovery of 39%. DHA was rather equally distributed in sn-1, -2 and -3 positions of TAG. The results show that both the fatty acid specificity and regiospecificity of the lipase as well as the fatty acid distribution of the oil should be considered when choosing the strategy for fatty acid enrichment.
J PROFMULAAFRANCIS. "Enzymatic Synthesis of Lipophilic Rutin and Vanillyl Esters From Fish By Products. Accepted.". In: J. Agric. Food Chem. 2011. Plant Molecular Biology Reporter Vol. 27, pp. 79-85.; 2011. Abstract
p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: "Times New Roman"; }div.Section1 { page: Section1; } Lipase-catalyzed synthesis of lipophilic phenolic antioxidants was carried out with a concentrate of n-3 polyunsaturated fatty acids (PUFAs), recovered from oil extracted from Salmon (Salmon salar) by-products. Vanillyl alcohol and rutin were selected for the esterification reaction and obtained esters yields were 60 and 30 %, respectively. The antioxidant activities of the esters were compared with those of commercial butylated hydroxytoluene (BHT) and α-tocopherol using DPPH radical scavenging and thiobarbituric acid assays. In DPPH assay, rutin esters showed better activity than vanillyl esters and on the contrary in lipophilic medium, vanillyl esters were found to be superior to rutin esters. In bulk oil system, the antioxidant activities of rutin and vanillyl derivatives were lower than that of BHT and α-tocopherol but in emulsion, they showed better activity than α-tocopherol. By attaching PUFAs to natural phenolics, the PUFAs are protected against oxidation while PUFA improves the hydrophobicity of the phenolic which could enhance its function in lipid systems.
J PROFMULAAFRANCIS. "Evidence for the involvement of a tsetse midgut lectin-trypsin complex in differentiation of bloodstream-form trypanosomes. Insect Sci. Applic. 23(3). 197.". In: Bull Entomol Res. 2003 Feb;93(1):1-10. Springerlink; 2003. Abstract
The possibility to cross-species amplify microsatellites in fruit flies of the genus Ceratitis was tested with the polymerase chain reaction (PCR) by analysing 23 Ceratitis capitata (Wiedemann) microsatellite markers on the genomic DNA of three other economically important, congeneric species: C. rosa (Karsch), C. fasciventris (Bezzi) and C. cosyra (Walker). Twenty-two primer pairs produced amplification products in at least one of the three species tested. The majority of the products were similar, if not identical in size to those expected in C. capitata. The structures of the repeat motifs and their flanking sequences were examined for a total of 79 alleles from the three species. Sequence analysis revealed the same repeat type as the homologous C. capitata microsatellites in the majority of the loci, suggesting their utility for population analysis across the species range. A total of seven loci were differentially present/absent in C. capitata, C. rosa, C. fasciventris and C. cosyra, suggesting that it may be possible to differentiate these four species using a simple sequence repeat-based PCR assay. It is proposed that medfly-based microsatellite markers could be utilized in the identification and tracing of the geographical origins of colonist pest populations of the four tested species and in the assessment of their risk and invasive potentials; thereby assisting regulatory authorities in implementing quarantine restrictions and other pest control measures.
J PROFMULAAFRANCIS. "Enrichment of PUFA in Nile perch free fatty acids by selective enzymatic esterification and subsequent analysis using HPLC-ELSD.". In: European Journal of Lipid Science and Technology. 29 MAR 2011 DOI: 10.1002/ejlt.201000560. Wiley; 2011. Abstract
PUFA from oil extracted from Nile perch viscera were enriched by selective enzymatic esterification of the free fatty acids (FFA) or by hydrolysis of ethyl esters of the fatty acids from the oil (FA-EE). Quantitative analysis was performed using RP-HPLC coupled to an evaporative light scattering detector (RP-HPLC-ELSD). The lipase from Thermomyces lanuginosus discriminated against docosahexaenoic acid (DHA) most, resulting in the highest DHA/DHA-EE enrichment while lipase from Pseudomonas cepacia discriminated against eicosapentaenoic acid (EPA) most, resulting in the highest EPA/EPA-EE enrichment. The lipases discriminated between DHA and EPA with a higher selectivity when present as ethyl esters (EE) than when in FFA form. Thus when DHA/EPA were enriched to the same level during esterification and hydrolysis reactions, the DHA-EE/EPA-EE recoveries were higher than those of DHA/EPA-FFA. In reactions catalysed by lipase from T. lanuginosus, at 26 mol% DHA/DHA-EE, DHA recovery was 76% while that of DHA-EE was 84%. In reactions catalysed by lipase from P. cepacia, at 11 mol% EPA/EPA-EE, EPA recovery was 79% while that of EPA-EE was 92%. Both esterification of FFA and hydrolysis of FA-EE were more effective for enriching PUFA compared to hydrolysis of the natural oil and are thus attractive process alternatives for the production of products highly enriched in DHA and/or EPA. When there is only one fatty acid residue in each substrate molecule, the full fatty acid selectivity of the lipase can be expressed, which is not the case with triglycerides as substrates.
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