School of Biological and Life Sciences

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    EFFECTIVENESS OF BAOBAB-PEARL MILLET BLEND ON BONE MINERAL DENSITY OF WOMEN AGED 40-65 YEARS IN KITUI COUNTY, KENYA
    (Technical University of Kenya, 2024-03-01) Immaculate, Kieti
    Osteoporosis is a condition marked by low bone mass and bone tissue loss, which makes a person weak and frail. Osteoporosis, one of the most incapacitating diseases of older people, increases the risk of bone fractures, notably in the hip, spine, and wrist. Women over the age of 45 occupy a third of the hospital beds, on average. 24.3% of Kenyans are estimated to have osteoporosis. The main objective of the study will be to establish the nutrient content of baobab fortified pearl millet flour and assess its impact on bone health among women aged 40-65 years and with osteoporosis at Kitui East sub county, Kitui County. The study will adopt an experimental interventional trial study design. The sample size will be 93 female osteoporotic patients. Bone Mineral Density (BMD) data will be obtained by performing DEXA scan Absorptiometry tests on the women to get their Standard Deviation (SD) levels whereby a SD of 2.5 and above will be considered normal. Baobab dry fruit pulp, pearl millet and baobab fortified pearl millet flour will be analyzed for the nutrient content of selected nutrients of importance to bone health. Calcium, potassium, magnesium, iron, copper, vitamin C and zinc will be analyzed. The interventional trials on women with osteoporosis will make use of two formulations of pearl millet flour supplemented with baobab. Data on the study sample's nutritional status, physical activity level, and health-related characteristics will be gathered using a standardized questionnaire. With the exception of the nutritional status data, which will be entered and analyzed using the Nutri-survey computer package, data from the structured questionnaire will be entered and analyzed using SPSS version 19 software. Bone mineral density, the nutritional value of baobab-fortified pearl millet flour, and respondents' nutritional status will all be interpreted using World Health Organization (WHO) cutoff values. Chi-square (x 2 ) will be used to establish the associations between categorical data on BMD and Body mass Index (BMI). Persons Correlation (r) will be done to establish the association between continuous data. Data will be generated into means, frequencies and percentages and grouped into tables, charts and graphs. A p value of (p< 0.05) will be considered significant. Since many scientific researches has shown that majority of women don’t consume adequate bone health nutrients such as calcium in their diets, there is need of developing a nutrition intervention product which can provide the required bone health nutrients to prevent and manage osteoporosis
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    TOXICOLOGICAL CHARACTERIZATION OF SODIUM METABISULFITE AND MITIGATION OF ITS EFFECTS BY STANDARDIZED Ginkgo biloba EXTRACT (EGb-761) IN A MOUSE MODEL
    (2023-11-01) Wairimu, Nancy
    Sodium metabisulfite (SMB), is a biocide and antioxidant agent generally used as a preservative in food and beverage industries, but can oxidize to harmful sulfite radicals. A standardized Ginkgo biloba (EGb-761) is well characterized, with 24% flavone glycosides (primarily quercetin, kaempferol and isorhamnetin) and 6% terpene lactones (2.8-3.4% ginkgolides A, B and C, and 2.6-3.2% bilobalide). Notably, Ginkgolide B and bilobalide account for about 0.8% and 3% of the total extract, respectively. EGb-761 has demonstrated potent antioxidant and anti-inflammatory activity, beneficial for the treatment of toxicants and diseases that exhibit oxidative stress and inflammation. The present study sought to investigate the putative ameliorative effects of EGb-761 against SMB-induced toxicity in mice. Thirty-two male Swiss white mice were randomized into control, SMB-treated, SMB + EGb-761-treated and EGb-761-treated groups. EGb-761 (100mg/kg/day) and SMB (98mg/kg/day) were administered by gastric gavage for 40 days. Body and relative organ weight, haematological profile, serum electrolytes and lipid profile, tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ), IL-10, nitric oxide (NO),tissue malondialdehyde (MDA) and reduced (GSH) levels and organ damage and pathology have been estimated. Oral administration of EGb-761 restored SMB-induced decrease in body weight and prevented SMB-induced thrombocytopenia, leukocytosis and anaemia. Further, EGb-761-treatment protected against SMB-induced liver and kidney injury depicted by decreased serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, bilirubin, creatinine, urea, uric acid and albumin. Furthermore, EGb-761 treatment attenuated SMB-driven dyslipidemia and metabolic acidosis. Besides, EGb-761 supplementation abrogated SMB-driven oxidative stress as depicted by stabilized GSH levels in the brain, liver, kidney, spleen, heart and lungs. SMB induced a significant increase of tissue levels of MDA, NO, IFN-γ and TNF-α were abrogated by EGb-761 treatment. Histopathological analysis revealed that exposure to SMB resulted in liver and kidney damage. It was noted that EGb-761 nullified those adverse pathological lesions. In conclusion, these results demonstrate that oral administration of standardized Ginkgo bilobaattenuated SMB-induced alteration of hematological parameters, metabolic acidosis, inflammatory responses, oxidative stress and organ damage. These findings provide a novel approach that can be optimized for preventing or treating exposure due to SMB toxicity
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    PUTATIVE EFFECTS OF CYANOCOBALAMIN IN THE REGULATION OF INFLAMMATORY RESPONSES, OXIDATIVE STRESS AND PATHOPHYSIOLOGICAL EVENTS DURING SEVERE STAGE OF HUMAN AFRICAN TRYPANOSOMIASIS
    (2023-11-01) Oula, James
    Human African Trypanosomiasis (HAT) is a neglected tropical disease caused by T. b. rhodesiense and T. b. gambiense, with tsetse fly (Glossina spp) being the known vector. T. b. rhodesiense causes acute form of HAT in Africa. The severe late stage of the disease is characterized by infiltration of the brain through the blood brain barrier (BBB) as well as overwhelming inflammation and oxidative stress. Treatment of HAT is reliant on the stage of the disease and melarsoprol remains the drug of choice for treatment of late-stage HAT despite the fact that it causes post-treatment reactive encephalopathy (PTRE). It therefore implies that, new treatment strategies that control the breach of the BBB as well as inflammatory reactions and oxidative stress may benefit those on treatment. This study utilized cyanocobalamin (vitamin B12), a well characterized anti-inflammatory and anti-oxidant molecule to determine its effects on T. b. rhodesiense-driven deleterious events. Therefore, the objective was to determine the effects of cyanocobalamin in the regulation of immune response during T. b. rhodesiense infection. Mice were randomly assigned into four groups each containing 8 mice; with group one being the control. Group two was infected with 5.0 x 104 KETRI 2537 T.b.rhodesiense; group three was supplemented with 8mg/kg of vitamin B12 for two weeks before infection. For group four, administration of vitamin B12 was started 4 days post infection (dpi). The general health of the mice was assessed using rapid murine coma and behavior scale (RMCBS), while parasiteamia was determined microscopically. At 42 dpi, the mice were sacrificed to obtain blood, tissues and organs for various analyses. The statistical analysis was done by GraphPad Prism software package. One-way ANOVA was used to compare the treatment groups with controls, Tukey’s post-hoc test for internal comparisons and Log-rank (Mantel-Cox) test for survival analysis. The results were given as a mean ±SEM with the level of significance set at P <0.05.The results showed that vitamin B12 enhanced the survival rate of T.b.rhodesiense infected mice independent of parasitemia of antilog 8.7 organism/ml and prevented T.b.rhodesiense-induced disruption of the BBB. Notably, T.b.rhodesiense-induced hematological alteration leading to microcytic hypochromic anemia and leukocytosis was nullified in mice administered with vitamin B12. T.b.rhodesiens-induced dyslipidemia was reversed by vitamin B12. T.b.rhodesiense-induced elevation of the liver alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total bilirubin, urea, uric acid and creatinine for kidney damage markers were attenuated by vitamin B12. Vitamin B12 blocked T.b.rhodesiense-driven rise in pro-inflammatory cytokines (TNF-α and IFN-γ), nitric oxide (NO) and malonaldehyde (MDA). T.b.rhodesiense-induced depletion of glutathione (GSH) levels were attenuated in the presence of vitamin B12 in the brain, spleen and liver tissues; a clear indication of the anti oxidant activity of vitamin B12. The histological analysis of the brain and liver confirmed T.b.rhodesiense-driven damage of these vital organs; which was ameliorated by vitamin B12. In conclusion, treatment with vitamin B12 potentially protects against various pathological events associated with severe late-stage HAT and presents a great opportunity for further scrutiny to develop an adjunct therapy for severe late-stage HAT.
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    THE IMPACT OF SCHISTOSOMA MANSONI ON DISEASE SEVERITY OF SECONDARY INFECTION WITH TRYPANOSOMA BRUCEI RHODESIENSE IN A MOUSE MODEL
    (2023-11-01) MITALO, NANCY
    Human African Trypanosomiasis (HAT) and Schistosomiasis are neglected parasitic diseases found in the African continent. There’s paucity of data on the outcome during co-infection of S. mansoni and Trypanosoma brucei rhodesiense. This study was conducted to determine how primary infection with Schistosoma mansoni affects HAT diseases progression with a secondary infection with Trypanosoma brucei rhodesiense (T.b.r) in a mouse model. Female BALB-c mice (6-8 weeks old) were randomly divided into four groups of 12 mice each. The different groups were infected with Schistosoma mansoni (100 cercariae) and Trypanosoma brucei rhodesiense (5.0x104 ) separately or together. Twenty-one days’ post infection with T.b.r, mice were sacrificed and samples collected for analysis. The primary infection with S. mansoni significantly enhanced successive infection by T.b.r; consequently, promoting HAT disease severity and curtailing host survival time. T.b.r-induced neurological integrity impairment and breach of the blood brain barrier were markedly pronounced on co-infection with S. mansoni. Co-infection with S. mansoni and T.b.r resulted in microcytic hypochromic anemia characterized by suppression of RBCs, hematocrit, hemoglobin and red cell indices. Moreover, co-infection of the mice with the two parasites resulted in leukocytosis which was accompanied with elevation of basophils, neutrophils, lymphocytes, monocytes, and eosinophils. More importantly, co-infection resulted in significant elevation of alanine amino transferase (ALT), alkaline phosphatase (ALP), aspartate amino transferase (AST), total bilirubin, creatinine, urea and uric acid, markers of liver and kidney damage. Meanwhile, S. mansoni-driven dyslipidemia was significantly enhanced by co-infection of mice with T.b.r. Moreover, co-infection with S. mansoni and T.b.r led to a strong immune response characterized by significant increase in serum IFN-γ and TNF-α. T.b.r infection enhanced S. mansoni-induced depletion of cellular reduced glutathione (GSH) in the brain and liver tissues, indicative of lethal oxidative damage. Similarly, co-infection resulted in significant rise in nitric oxide (NO) and malondialdehyde (MDA) levels. In conclusion, primary infection with S. mansoni exacerbates disease severity of secondary infection with T.b.r in a mouse model that is linked with harmful inflammatory response, oxidative stress and organ injury
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    OUTCOME OF CHRONIC SCHISTOSOMIASIS IN REGULATION OF MALARIA DISEASE SEVERITY AND PATHOLOGICAL EVENTS IN A MOUSE MODEL
    (Technical University of Kenya, 2022-05-01) MUGANDA, ANDREW
    First, I wish to thank the Almighty God for the strength, good health, and focus for making this journey possible. Special thanks to my supervisors Dr. Edward Okonjo, Dr. James Nyabuga and Prof. Dorcas Yole, for the excellent supervision, commitment and guidance throughout the development of this thesis. I extend my gratitude to my supervisors for helping in conceptualization of the idea and putting it together. Furthermore, for walking with me throughout the research journey. In addition, my supervisors were very committed in ensuring that I overcome my challenges during experimental stages and helping me understand that drawbacks are avenues for learning. I am grateful to the staff at the Department of Applied and Technical Biology and Department of Biochemistry and Biotechnology at TU-K for the assistance during my laboratory sessions and I appreciate them for providing me with the necessary academic support that enabled me to finish my studies. Special thanks to the Muganda’s family, may God bless you abundantly for walking with me and encouraging me to focus on the finish line.
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    THE ROLE OF KHAT IN EXACERBATING MANGANESE-INDUCED DELETERIOUS EFFECTS AND PUTATIVE RESCUE BY COENZYME-Q10 IN A MOUSE MODEL
    (Technical University of Kenya, 2022-06) WEKESA, KENNEDY CHEPUKOSI
    ABSTRACT Khat, a plant containing phytochemicals that act as psychostimulants is widely grown and used in Kenya and East Africa. It contains amphetamine-like chemicals, cathine and cathinone, largely responsible for hematotoxicity and organ damage. There is growing use of this herb in rural and urban areas heavily polluted with environmental toxicants. Limited research has been done on khat toxicity, more so, on how to counter it. In addition, there is limited information on the biochemical, physiological and neurological changes due to co-exposure to khat and the other metal toxicants commonly present in polluted environments, such as manganese. This study was conducted to elucidate the toxicological profile of khat with or without manganese and the putative ability of coenzyme-Q10 (CoQ10) to modulate negative physiological and biochemical processes due to khat and manganese-induced toxicities. This laboratory-based research involved the use of a well characterized mouse model in which the groups of Swiss albino mice were either treated with khat or manganese or CoQ10 or the three treatments combined. Group one was the control group that was not given any of the treatments; group two was supplemented with CoQ10 (200mg/kg b/w); group three was given khat extract (1500mg/kg b/w); group four had free access to water dissolved in manganese ad libitum (4g/L); group five was co-treated with CoQ10 (200mg/kg b/w) and khat (1500mg/kg b/w); group six was given CoQ10 (200mg/kg b/w) and had free access to manganese in water (4g/L); group seven was given khat (1500mg/kg b/w) and had free access to manganese dissolved in water (4g/L b/w), lastly, group eight was treated with CoQ10 (200mg/kg b/w) and khat (1500mg/kg b/w) and had free access to manganese in water ad libitum (4g/L). The study was conducted in two phases to simulate subchronic (90 days) and chronic (132 days) exposure to khat. A series of experiments were performed according to the study objectives. They included: monthly body weight measurements and rapid murine and behavioral score (RMCBS), biochemical assay for liver and kidney biomarkers, reduced glutathione (GSH) assay for oxidative damage, cytokine assay for changes in immune response and histology for organ pathology. Subchronic and chronic exposure to khat induced hematological perturbations leading to anemia that were nullified in the presence of CoQ10. During the subchronic phase, khat caused neurological disturbance that was exacerbated on exposure to manganese (khat+Mn++). However, CoQ10 appeared to restore the khat and manganese-induced neurological dysfunctions. Additionally, there was severe hepatotoxicity and nephrotoxicity following simultaneous exposure to khat and manganese as depicted by the elevated liver (AST, ALT, GGT, total bilirubin) and kidney (creatinine) biomarkers. Notably, supplementation with CoQ10 attenuated khat and/or manganese-induced hepatotoxicity and nephrotoxicity. Exposure to khat for 90 days and 132 days resulted in oxidative damage in the brain, liver and kidney as depicted by the significant GSH elevation. Nonetheless, supplementation with CoQ10 nullified the oxidative damage. Further findings revealed that, in the presence of manganese, the oxidative damage was enhanced; with CoQ10 suppressing the heightened oxidative damage. Lastly, subchronic and chronic exposure to khat caused inflammation which was enhanced in the presence of manganese as exhibited by the increased levels of the pro-inflammatory cytokines (TNF-α and IFN-γ). Notably, CoQ10 modulated khat and/or manganese driven proliferation of inflammatory cytokines. The results in the current study demonstrate that khat negatively affects vital physiological and biochemical processes and induces multiple organ damage and affects the immune system. Moreover, and for the first time, the results show that chronic exposure to manganese exacerbated multiple forms of toxicities following co-exposure with khat. Additionally, the outcomes demonstrate that CoQ10 may be considered as an appropriate pharmacological mitigation against khat-driven toxicity.
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    PHYLOGENETIC DIVERSITY AND TOXIGENIC POTENTIAL OF FUSARIUM SPECIES IN WHEAT AND LEVELS OF DEOXYNIVALENOL AND FUMONISINS IN MARKET WHEAT PRODUCTS, KENYA
    (Technical University of Kenya, 2023-11) OTIENO, PHANICE KHESELI
    ABSTRACT In Kenya, wheat is the second most consumed cereal grain after maize and provides nutrition for about 50% of the world's population. However, production of the grain often faces setbacks occasioned by fungal infections and the related chemical contaminants. Unrelenting fungal disease control system, sufficient wheat seed system and observation of food safety measures to curb deficiency and alleviate ill health associated with consumption of mycotoxin contaminated wheat products is essential. This study assessed farmers’ knowledge on fungal wheat diseases and, their practices in choices of wheat cultivars cropped in three ecological regions of Kenya. Prevalence and diversity of Fusarium species in the produce of farmer saved and certified seeds of wheat cultivars was also analyzed. In addition, the genetic ability of the isolated Fusarium spp. to produce mycotoxins was evaluated. Lastly, a survey to investigate occurances and levels of fumonisins and deoxynivalenol (DON) in selected market wheat products sampled in Narok town, Nakuru city and Nairobi, the capital city of Kenya was done. Two hundred and sixty wheat grain samples were collected from 123 farms in Narok, Uasin Gishu and Nakuru Counties between 2016 and 2017. Peptone Pentachloro-nitrobenze Agar was used for isolation of Fusarium spp. from the grains samples, while PDA, CLA and SNA media were used for cultural and morphological characterization. Fusarium species identity and diversity was determined using sequence analysis of the gene encoding translation elongation factor 1-alpha (tef1-alpha). The genetic ability of the Fusarium spp. to produce mycotoxins was determined using Tri13F/Tri13RDON and FUM1F/FUM1R primer pairs. ELISA Kit protocols were used for assessment of mycotoxin levels. ANOVA, the Tukey HSD test and microscopy were used for data analysis. Notably, barely 10% of wheat cultivars released into the Kenyan market were under cultivation in the targeted areas within the study period. In all the three regions, Njoro BWII wheat cultivar was the most preferred and the most frequently (48.8%) sampled wheat cultivar. Top on the list of agroeconomic factors that influenced the selection of wheat cultivars to plant were the weight of wheat grains at harvest and the resilience of wheat cultivars to wheat rust. Other than wheat rust, most farmers had limited knowledge about other fungal diseases while only 1.63% of them cited Fusarium head blight (FHB) as a problematic fungal disease in wheat production. Eight Fusarium spp. (Fusarium poae, F. verticillioides, F. equiseti, F. heterosporum, F. tricinctum, Fusarium sp. F. oxysporum, and F. culmorum) were identified. However, the species diversity in the study regions did not differ significantly. While certified commercial wheat seeds produced 33.75 percent of the recovered Fusarium spp., wheat grains from farmer-saved seeds produced 66.25%. Tri13DON gene was not detected in the isolated putative DON producers while FUM1 gene was detected in 60% of the isolated Fusarium species. Over 76% of the analyzed wheat grain samples had detectable levels of fumonisins. However, the highest level (9.6ppm) did not exceed the permissible levels of between 2000μg/kg and 4000μg/kg in whole grains according to EU guidelines. Over 75% of the sampled market wheat products contained levels of DON and fumonisins that were below the permissible maximum limits of 750μg/kg according to EU guidelines. Wheat flour contained the highest concentration of DON (5.6 μg/kg). The significant research finding is that a minimal percentage of wheat cultivars released into the market had been cultivated in the studied regions. Among other factors, farmers did not prioritize selection of cultivars based on their ecological growth requirements and they notably had minimal knowledge about other serious wheat fungal diseases such as FHB to the extend of referring to all diseases observed on the crop as wheat rust. Fusarium spp. with the ability to produce mycotoxins were prevalent in the wheat cultivars sampled in the three study areas. This calls for intensified integrated control measures of the pathogens across the three regions. Finally, the quantities of DON and fumonisin found in the wheat products from the market samples were within acceptable limits. Hence, this result highlights the safety of the products for human consumption. However, frequent surveys are recommended to ascertain consistency in the levels of the toxins within the recommended measures. More extension services are also needed to educate wheat farmers on all-important qualities of wheat cultivars released in the market. Lastly, enhancement of awareness on the prevalence of other dangerous fungal diseases such as FHB, it’s related health affecting mycotoxins and how farmers can participate in the control of such diseases.
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    ISOLATION AND CHARACTERIZATION OF LACTOBACILLUS AND WEISSELLA STRAINS FROM KIMERE TOWARDS DEVELOPMENT OF A NOVEL PROBIOTIC YOGHURT FOR AFLATOXIN B1 CONTROL
    (Technical University of Kenya, 2022-01) NDUTI, NICHOLAS NDARU
    In Kenya, maize is an important staple food. Unfortunately, household maize is generally spoilt by fungi whose mycotoxin metabolites have been found to cause adverse effect to animal and human health. The study had four objectives: i) to determine aflatoxin levels in maize and maize flours in three different selected regions in Kenya. ii) To isolate and characterize Lactobacillus and Weissella strains in Kimere and determine their individual strain capacity to sequester aflatoxins. iii) To assess growth of the isolated Lactobacillus and Weissella strains in milk so as to develop a novel yoghurt using the highest Lactobacillus and Weissella aflatoxins binding strains. iv) To determine the capacity to lower aflatoxin B1 (AFB1) metabolite (aflatoxin M1) in urine of children from Eastern Kenya by Lactobacillus and Weissella isolated strains. To achieve the objectives, 75 maize grains and 27 flour samples were collected from three parts of Kenya and analysed for aflatoxins by Enzyme linked immunosorbent assay (ELISA) plus spectrophotometric technique. Basic and advanced molecular microbiology techniques were employed to obtain Lactobacillus and Weissella isolates from Kimere. These included growing the Lactobacillus and Weissella in a selective media followed by Gram staining. To identify the species of the isolated Lactobacillus and Weissella, Polymerase Chain Reaction (PCR) was used to amplify the DNA extracts. DNA blocks were sequenced and identified using the Blast software process. A novel yoghurt was developed using an isolate of Lactobacillus rhamnosus and Weissella, along with starter culture Streptococcus thermophilus. The capacity of the isolates to sequester or bind AFB1, in vitro and in vivo was determined using ELISA. Where applicable High Performance Liquid Chromatography (HPLC) as well as Spectrophotometric techniques were used. Sequestration of AFB1 in vivo was examined indirectly by measuring aflatoxin M1 (AFM1) in urine of school children in Eastern Kenya whose diet was mainly maize or maize-based. Samples of urine from children were analyzed by ELISA, and Liquid chromatography-mass spectrophotometry combination (LC-MS). The results for objective one showed a significant difference between the AFB1 levels in Maize grains (P<0.05) from different regions. Maize samples from Eastern Kenya region had the highest contamination. Maize samples from Nairobi had the lowest concentration at 6.02±0.31145 ppb. There was no significant difference in the total aflatoxins in Maize flour samples from all regions (P>0.05). Moreover there was significant difference in AFB1 concentrations between stores for example from Western and Eastern regions (P<0.05). Total aflatoxin levels in maize flours were slightly above international standard of 5ppb but lower than the Kenyan standard which is 10 ppb. The results for objective two indicated that out of 300 isolates from Kimere that were analysed for capacity to lower the risk of aflatoxin exposure in vivo or in vitro, Weissella cibaria NN20 had highest but statistically insignificant survival in low acidic condition than probiotic Lactobacillus rhamnosus GR-1 and Escherichia coli GR12 (P>0.05). Weissella cibaria NN20 bound 43.7±2.3 % of total available AFB1 in modulated media. Objective three and four had results showing that lactobacillus isolated from Kimere had capacity to ferment milk same as yoghurt and be able to reduce aflatoxin M1 in urine in vivo from 6.3ppb to 2.6ppb. The results confirmed the hypothesis that consumers were at a risk of aflatoxin exposure and that they were indeed consuming the AFB1 contaminated maize and maize products. In conclusion, the findings confirmed relatively high concentrations of Aflatoxins in maize and maize flours despite government efforts to prevent this. These results call for further intervention at table level. The Lactobacillus and Weissella isolates reduced AFB1 both in vitro and in vivo, suggesting that probiotic yoghurt has the potential to prevent aflatoxicosis among consumers of maize and maize based diets.
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    APPLICATION OF STRUCTURAL BIOINFORMATICS IN AFRICAN SWINE FEVER VIRUS ANTIVIRAL DEVELOPMENT
    (Technical University of Kenya, 2022-07) KINYANYI, DICKSON BENNET
    African swine fever (ASF) is a fatal hemorrhagic disease of domesticated pigs that is caused by the African swine fever virus (ASFV). This disease poses a threat to food security thus leading to economic losses. Presently, there are no reports of approved available vaccines for ASF. Despite the ASFV sequences having well-conserved promoter motifs, no protein with features able to bind onto the promoter TATA-like elements has been identified, nor an antiviral capable of targeting viral TATA-like elements involved in ASFV transcription. This study aimed at finding a TATA Binding Protein (TBP) and potential minor groove binders (MGBs) that can target conserved promoter motifs in ASFV. The study implemented sequence-based search methods followed by three-dimensional structure modeling. The posterior probability of fold family classification was calculated using TM-fold, and biological function was determined using TM-site, RaptorXBinding Site, Gene Ontology, and TM-align. Subsequently, congocidine congeners, Hoechst 33258, and tris-benzimidazole were selected as potential minor groove binders targeting synthetic DNA constructs containing TATA-like motifs mimicking conserved ASFV promoters. The binding scores and calculated binding energies of docked DNA-ligands complexes were evaluated. The ligand behaviour within the minor grooves was assessed using molecular dynamics (MD) simulation. The results of this study established that the three-dimensional structure of a previously uncharacterized protein pB263R had features similar to a TBP with a TM-score of 0.52, with  95% posterior probability. Additionally, the selected minor groove binders were able to significantly dock on the AT-rich regions of the synthetic DNA constructs containing TATA-like motifs. Further, calculated binding energies revealed that less cytotoxic congocidine congeners and tris-benzimidazole were an improvement of cytotoxic congocidine. The MD simulation and molecular trajectory visualization revealed that the ligands remained embedded in the minor grooves of synthetic DNA constructs during the MD simulation time course. The findings of this study suggest that these ligands may be used as potential antivirals for ASF infection in abrogating ASFV transcription. Critical for control of several ASFV genotypes.
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    THE ROLE OF COENZYME-QlO IN THE REGULATION OF ThTFLAMMATORY IMMUNE RESPONSES DURING EXPERIMENTAL CEREBRAL MALARIA IN MICE
    (TUK, 2019-06) NYARIKI, JAMES NYABUGA
    Cerebral Malaria (CM) is a form of malaria that causes a complex neurological syndrome, whose ~ology is mediated by severe inflammatory processes triggered by the immune system of the : 5t following infection with Plasmodium Jalciparum. There is limited progress in the -. development of new approaches for the treatment of CM. The aim of this study was to -~-:ematically elucidate the putative impact of oral administration of Coenzyme-QlO (CO-QIO) on ~ initiation or regulation of inflammatory immune response in experimental cerebral malaria \1). In addition, the ability of CO-Q lO to assuage ECM-induced inflammation and oxidative _ss was detennined. For this purpose, one group of C57BLl6J mice was used as control; the _::lnd group was infected with Plasmodium berghei ANKA (PbA) and the third group of mice -. orally supplemented with 200mglkg CO-Q IO and then infected with PbA. Within this -:--erimental set up, a series of experiments were carried out in concert with the study objectives. _... included: survival analysis, extensive clinical and biochemical analyses, flow cytometry, rime PCR for mRNA levels, immunoblot and immune-based assays. It was observed that __dministration of CO-QlO both before and after PbA infection protected majority of mice --J ECM. Importantly, CO-QIO supplementation significantly hampered infiltration of -lmatory monocytes, T cells and cytotoxic granzyme B into the brain. Brain tissue analysis ed a reduction in the expression levels of inflammatory transcripts TNF -u and MIP-l ~ in administered mice. Furthermore, CO-QlO administration resulted in decreased expression -~okines (CXCL9, CXCL 10) in the brain, leading to reduced levels of activated pathogenic _ -with concomitant improvement in blood brain barrier disruption. In addition, CO-QIO __ 91ed the differentiation and maturation of both splenic and brain dendritic cells during '\otably, anti-inflammatory cytokines IL-IO and IL-22 together with T-regulatory celis, -are associated with protection during ECM, were up-regulated in CO-QlO treated mice. -. ably, Co-QJO was very effective in decreasing NF-KB phosphorylation, which is _ -:-00 with ECM pathology. Splenic analysis of innate lymphoid class two (ILC2), which -.ll to playa protective role during ECM, showed augmentation in the spleens of CO-QIO . . ered mice. Meanwhile, levels of matrix metalloproteinases-9 and angiopoietin-l&2, :!..."'e linked to severity of CM were reduced in mice administered with CO-QIO. '----~~. . e. CO-Q IO supplementation abrogated malondialdehyde, diene and 8-hydroxy:'::::::trr:--2 osine \8-0HDG( which are markers of oxidative stress and DNA damall>e. Moreover,