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Item Obesity and Factors that Contribute to Obesity among Pre- Adolescents Attending Day Private Primary Schools in Nairobi, Kenya(2015-09-01) Malla, Janet Kajuju; Waudo, Prof. Judith; Kithinji, Dr. Ciriaka T.Obesity is a diet-related condition and it refers to an abnormally high proportion of body fat. Various studies carried out in the United States reveal that obesity stems right from childhood. Childhood obesity is the most prevalent and common nutritional condition among the urban population and it is becoming an area of public concern. Cited literature suggests that feeding habits, especially during infancy and childhood predisposes the child to obesity in adulthood. This was a descriptive study aimed at investigating obesity and factors that contribute to obesity among Pre-adolescents. The respondents were randomly selected from two day private primary schools in Nairobi. Systematic random sampling was used to select pupils from each school making a sample of 120 pupils. School head-teachers were also included in the sample. Data were collected by use of questionnaires, an interview schedule and an observation checklist. Both qualitative and quantitative data were collected. Qualitative data were analyzed by coding raw data into common themes to form patterns. Quantitative data were analyzed by computer through the use of Statistical Package for Social Sciences (SPSS). Linear regression analysis was used to test the hypothesis. Results were reported using frequencies and percentages. The study showed that there was a significant relationship between eating habits of the pre-adolescents and obesity. Eating food three times a day and eating any time were positively correlated with obesity. In the schools studied, 40% of the respondents ate food three times in a day while (50%) consumed food at any time of the day. The reasons given for these trends of food consumption were: availability of money, peer pressure, boredom and influence by media. Skipping meals had a very significant relationship with obesity. The t-statistic of –2.88 was significant at 5% significant level. This implied that an obese person could reduce their BMI by 2.0 points by skipping meals. On the other hand, eating between meals was positively correlated with obesity and the result was significant at 10% significant level. Data collected indicated that 55.8% of the respondents ate between meals. A third of the respondents were found to have a BMI of over 26, which indicates evidence of overweight.Item In vitro Anti-plasmodial Activity of Rubia cordifolia, Harrizonia abyssinica, Leucas calostachys Olive and Sanchus schweinfurthii Medicinal Plants.(2013) Nyambati, GK; Lagat, ZO; Maranga, RO; Samuel, M; Ozwara, HPlasmodium falciparum is becoming increasingly resistant to conventional antimalaria drugs. Rapid increase of parasite resistant strains, resistance of the vector to insecticides and the difficulty in creating efficient vaccines has lead to an urgent need for new anti-malarial drugs. To determine anti-plasmodial activity of Rubia cordifolia, Harrizonia abyssinica, Sachus schweinfurthii and Leucas calostachys Olive plants. Aqueous and methanolic crude extracts were prepared from R. cordifolia, H. abyssinica, S. schweinfurthii and L. calostachys plants. The extracts were then prepared into appropriate concentrations for anti-plasmodial activities. In vitro anti-plamsodial activities of herbal drugs were analysed according to the methods of Tona et al., 1999. Methanolic extracts were more efficacious than aqueous extracts. S. schweinfurthii and L. calostachys had IC50 (Inhibition Concentration) of between 1.10μg/ml and 3.45μg/ml and had highest parasite inhibition ranging between 3.5% and 5.2%. R. cardifolia and H. abyssinica had IC50 of between 1.5μg/ml and 3.0μg/ml and it had moderate parasitaemia ranging between 5.20% and 7.22%. Vernonia lasiopa and Erythrina abysinnica had insufficient yields. S. schweinfurthii and L. calostachys had the highest parasite inhibition while R. cardifolia and H. abyssinica had moderate inhibitionItem Coenzyme Q10 prevented full blown splenomegaly and decreased melarsoprol-induced reactive encephalopathy in mice infected with Trypanosoma brucei rhodesiense(2014) Nyariki, James Nyabuga; Thuita, John Kibuthu; Nyambati, Grace Kemunto; Isaac, Alfred OrinaObjective: To establish the modulatory effects of coenzyme Q10 on experimental trypanosome infections in mice and evaluate the risk of occurrence and severity of melarsoprol-induced post treatment reactive encephalopathy (PTRE). Methods: Female Swiss white mice were orally administered with 200 mg/kg of coenzyme Q10 after which they were intraperitoneally inoculated with Trypanasoma brucei rhodesiense (T. b. rhodesiense). The resultant infection was allowed to develop and simulate all phases of human African trypanosomiasis and PTRE. Parasitaemia development, packed cell volume, haematological and pathological changes were determined. Results: A histological study in the brain tissue of T. b. rhodesiense infected mice demonstrated neuroinflammatory pathology which was highly amplified in the PTRE-induced groups. A prominent reduction in the severity of the neuroinflammatory response was detected when coenzyme-Q10 was administered. Furthermore, the mean tissue weight of spleen to body ratio in coenzyme Q10 supplemented group was significantly (P<0.05) different compared to unsupplemented groups, and clearly indicated that coenzyme Q10 prevented full blown splenomegaly pathogenesis by T. b. rhodesiense. A significant (P<0.05) increase in hemoglobin levels and red blood cells was observed in coenzyme Q10 mice compared to those infected and un-supplemented with coenzyme Q10. Conclusions: The capacity of coenzyme Q10 to alter the pathogenesis of T. b. rhodesiense infection in mice and following treatment with melarsoprol, may find application by rendering humans and animals less susceptible to deleterious effects of trypanosome infection such as splenomegaly and melarsoprol-induced PTRE and neurotoxicity.Item Evaluation of the Anticonvulsant Activity of the Leaf Methanol Extract of Crassula arborescens (Mill.) Willd. (Crassulaceae) in Mice(2014) Amabeoku, George Jimboyeka; Mbamalu, Oluchi Nneka; Davids, Tasneem; Fakude, Samukelisiwe; Gqwaka, Anda; Mbai, Fiona N; Pieterse, Reighman; Shaik, AneesaCrassula arborescens (Mill.) Willd. subsp. Arborescens is widely used for the treatment of various ailments including diarrhoea, corns, epilepsy and as a purgati ve. However, no information exists in any literature to verify the acclaimed effecti veness of C. arborescens in the treatment of the various ailments. The study, therefore, intended to investigate the anticonvulsant activity of the leaf methanol extract of C. arborescens in mice. Acute toxicity study and phytochemical qualitative analysis of the plant extracts were also carried out. Chemically-induc ed convulsion methods were used to assess the anticonvulsant activity of C. arborescens . Standard methods were used for the acute t oxicity study and phytochemical analysis of the chemical compone nts of the plant extr act. PTZ (pentylenetetrazole), bicuculline, picrotoxin, NMDLA (N-methy l-DL-aspartic acid) or strychnine produced tonic convulsions i n all the mice used. Leaf methanol extract of Crassula arborescens , muscimol, phenobarbitone or di azepam significantly antagonised PTZ, bicuculline or picr otoxin-induced convulsion. C. arborescens or LY233053 significantly antagonised NMDLA-induced tonic convulsion. C. arborescens or phenobarbitone signifi cantly antagonised strychni ne-elicited tonic convulsi on. Phenytoin or DMSO (dimethylsulfoxide) did not significantly affect the tonic convulsion produced by PTZ, bicuculline, picrotoxin, NMDLA or strychnine. The LD 50 value obtained from intraperitoneal administration of C. arborescens was 781.6 mg/kg while that following oral administration of the plant extract was over 4,000 mg/kg. The phytochemical qualitativ e analysis done showed the presence of flavonoids, tannins, reducing sugar, saponins and triterpene steroids. The data obta ined in the study show that the leaf methan ol extract of Crassula arborescens has anticonvulsant activity which may be underpinned by GABAergic, glutaminergic and glycinergic mechanisms. The high LD 50 value obtained following the oral administra tion of the plant extract shows that the leaf methanol extract is non-toxic to animals.Item Reply to “Letter to the Editor: ‘Understanding the WHI gap’(2012) Pechenino, Angela S; Lee, Alison R; Lin, Li; Mbai, Fiona N; Stallone, John N; Knowlton, AAThis is a reply in response to Drs. Kerber's and Turner's commentary about our article (10) in Physiological Genomics. We thank Kerber and Turner for their enthusiastic response to our article and are pleased that they found it useful in their practice (10). However, we would like to point out that the link between estrogen therapy postmenopause and a decrease in dementia in older women is tenuous at best. Few studies indicate definitively that hormone replacement therapy (HRT) results in a decrease in dementia, and most only point toward a possibility that has yet to be realized (5). Basic studies in rodent models suggest that estrogen replacement can reduce brain injury in models of stroke, but more work is needed before taking these findings to the clinical setting (1). Additionally, the Women's Health Initiative (WHI) and the Million Woman Study indicate that breast cancer risk increases significantly when women are put on HRT, specifically with estrogen and progesterone taken in combination, a finding that should limit the use of HRT to those women who do not already manifest a high risk for breast cancer (2, 9). In contrast to chronic estrogen replacement, there is a small, but growing, literature supporting a role for a protective role of estrogen in acute injury (11–13). We and others have found that treatment with a high concentration of 17β-estradiol at the time of injury can greatly reduce inflammation and apoptosis (3, 4, 6, 14). Such limited use of E2 will not increase the risk of cancer but does have the possibility of greatly reducing tissue injury. We feel that a more promising area for the treatment of postmenopausal symptoms comes from the selective estrogen receptor modulators (SERMs). For example, raloxifene improved verbal memory in postmenopausal women when given over a period of 5 yr.(7) In contrast tamoxifen, a SERM that is primarily an estrogen antagonist, was associated with poorer performance on letter fluency and manual dexterity in women with breast cancer compared with untreated controls (8). Many SERMs have been synthesized, and some may have the positive, protective effects of estrogen without promoting cell proliferation and cancer. More work will be needed identifying the specific effects of these compounds before this type of treatment can be applied in the clinic to ameliorate aging-associated changes such as cardiovascular disease and dementiaItem Gender differences in cardiovascular disease: The effects of estrogen(2005) Mbai, Fiona N; Hamilton, Karyn L; Knowlton, Anne AEstrogen and its therapeutic application in cardiovascular disease are highly controversial. There has been a paucity of basic research on estrogen and its molecular effects, which has weakened the underpinnings of clinical trials of estrogen treatment. In the past 10 years, much has been discovered about both the genomic and nongenomic effects of estrogen. The identification of at least three distinct receptors for estrogen, as well as the development of drugs with varying binding affinities for different receptors, has created exciting therapeutic possibilities.Item A Venue-Based Approach to Reaching MSM, IDUs and the General Population with VCT: A Three Study Site in Kenya(2012) Singh, Kavita; Brodish, Paul; Mbai, Fiona N; Kingola, Nzioki; Rinyuri, Agnes; Njeru, Carol; Mureithi, Patrick; Sambisa, William; Weir, SharonA venue-based HIV prevention study which included Voluntary Counseling and Testing (VCT) was conducted in three diverse areas of Kenya—Malindi, Nanyuki and Rachounyo. Aims of the study were to: (1) assess the acceptability of VCT for the general population, men who have sex with men (MSM), and injecting drug users (IDUs) within the context of a venue-based approach; (2) determine if there were differences between those agreeing and not agreeing to testing; and (3) study factors associated with being HIV positive. Approximately 98% of IDUs and 97% of MSM agreed to VCT, providing evidence that populations with little access to services and whose behaviors are stigmatized and often considered illegal in their countries can be reached with needed HIV prevention services. Acceptability of VCT in the general population ranged from 60% in Malindi to 48% in Nanyuki. There were a few significant differences between those accepting and declining testing. Notably in Rachuonyo and Malindi those reporting multiple partners were more likely to accept testing. There was also evidence that riskier sexual behavior was associated with being HIV positive for both men in Rachounyo and women in Malindi. Overall HIV prevalence was higher among the individuals in this study compared to individuals sampled in the 2008–2009 Kenya Demographic and Health Survey, indicating the method is an appropriate means to reach the highest risk individuals including stigmatized populations.Item Rapid Activation of Nuclear Factor-κB by 17β-Estradiol and Selective Estrogen Receptor Modulators: Pathways Mediating Cellular Protection(2012) Stice, James P; Mbai, Fiona N; Chen, Le; Knowlton, Anne A17 β -estradiol (E2) treatment activates a set of protective response that have been found to protect cells from injury and more importantly to significantly abate the injuries associated with trauma- hemorrhage in vivo . Rapid NF κ B activation has been found to be an important signaling step in E2 mediated protection in cell culture, in vivo ischemia and trauma-hemorrhage. In the current study, we investigated the signaling cascades linking E2 signaling with NF κ B activation and the protective response, and compared them with the effects of two selective estrogen receptor modulators (SERMs), raloxifene and tamoxifen. Two candidate pathways, mitogen activated protein kinases (MAPK), and phosphatidylinositol-3-kinase (PI3-K) were studied. Selective inhibitors were used to identify each pathway's contribution to NF κ B activation. Treatment of HCAECs with E2 activated PI3-K/Akt, p38, and JNK, all of which activated ERK 1/2 followed by NF κ B activation. The combined activation of Akt, p38 and JNK was essential to activate NF κ B. The two SERMs activated PI3-K and p38, which then phosphorylated ERK 1/2 and activated NF κ B independent of the JNK pathway. NFkB activation by these compounds protected cells from hypoxia/reoxygenation injury. However, E2, unlike either SERM, led to modest increases in apoptosis through the JNK pathway. SERM treatment led to increased expression of the protective proteins, Mn-superoxide dismutase and endothelial nitric oxide synthase, that was not seen with E2. These results provide new insight into the pathways activating NFkB by E2 and SERMS and demonstrate that SERMs may have greater protective benefits than E2 in adult endothelial cells and potentially in vivo , as wellItem Effects of Dietary Decosahexaenoic Acid (DHA) on eNOS in Human Coronary Artery Endothelial Cells(2008) Stebbins, Charles L; Stice, James P; Hart, Michael; Mbai, Fiona N; Knowlton, Anne AEndothelial dysfunction occurs in heart disease and may reduce functional capacity via attenuations in peripheral blood flow. Dietary decosahexaenoic acid (DHA) may improve this dysfunction, but the mechanism is unknown. This study determined if DHA enhances expression and activity of eNOS in cultured human coronary artery endothelial cells (HCAEC). HCAEC from 4 donors were treated with 5 nM, 50 nM, or 1 μM DHA for 7 days to model chronic DHA exposure. A trend for increased expression of endothelial nitric oxide synthase (eNOS) and phospho-eNOS was observed with 5 and 50 nM DHA. DHA also enhanced expression of 2 proteins instrumental in activation of eNOS: phospho-Akt (5 and 50 nM) and HSP90 (50 nM and 1 μM). Vascular endothelial growth factor–induced activation of Akt increased NOx in treated (50 nM DHA) versus untreated HCAEC (9.2 ± 1.0 vs 3.3 ± 1.1 μmol/μg protein/μL). Findings suggest that DHA enhances eNOS and Akt activity, augments HSP90 expression, and increases NO bioavailability in response to Akt kinase activationItem Impact of aging vs. estrogen loss on cardiac gene expression: estrogen replacement and inflammation(2011) Pechenino, Angela S; Lin, Li; Mbai, Fiona N; Lee, Alison R; He, Xian-Min; Stallone, John N; Knowlton, AADespite an abundance of evidence to the contrary from animal studies, large clinical trials on humans have shown that estrogen administered to postmenopausal women increases the risk of cardiovascular disease. However, timing may be everything, as estrogen is often administered immediately after ovariectomy (Ovx) in animal studies, while estrogen administration in human studies occurred many years postmenopause. This study investigates the discrepancy by administering 17β-estradiol (E2) in a slow-release capsule to Norway Brown rats both immediately following Ovx and 9 wk post-Ovx (Late), and studying differences in gene expression between these two groups compared with age-matched Ovx and sham-operated animals. Two different types of microarray were used to analyze the left ventricles from these groups: an Affymetrix array (n = 3/group) and an inflammatory cytokines and receptors PCR array (n = 4/group). Key genes were analyzed by Western blotting. Ovx without replacement led to an increase in caspase 3, caspase 9, calpain 2, matrix metalloproteinase (MMP)9, and TNF-α. Caspase 6, STAT3, and CD11b increased in the Late group, while tissue inhibitor of metalloproteinase 2, MMP14, and collagen I α1 were decreased. MADD and fibronectin were increased in both Ovx and Late. TNF-α and inducible nitric oxide synthase (iNOS) protein levels increased with Late replacement. Many of these changes were prevented by early E2 replacement. These findings suggest that increased expression of inflammatory genes, such as TNF-α and iNOS, may be involved in some of the deleterious effects of delayed E2 administration seen in human studiesItem Deciphering the reproductive protein-protein interaction network in Anopheles gambiae with Drosophila melanogaster as a framework(2011) Achinko, Daniel; Mireji, Paul O; Catteruccia, Flaminia; Masiga, DanProtein-protein interactions (PPIs) are the most fundamental biological processes at the molecular level. The experimental methods for testing PPIs are time-consuming and are limited by analogs for many reactions. As a result, a computational model is necessary to predict PPIs and to explore the consequences of signal alterations in biological pathways. Reproductive control of the vector Anopheles gambiae using transgenic techniques poses a serious challenge. To meet this challenge, it would help to define the biological network involving the male accessory gland (MAG) proteins responsible for successful formation of the mating plug [1]. This plug forms in the male and is transferred to the female during mating, hence initiating the PPIs in both sexes. As is the case in Drosophila melanogaster, a close relative of A. gambiae, some MAG proteins responsible for the formation of the mating plug have been shown to alter the post-mating behavior of females.Item Life stage and tissue speciation of cathepsin B (AGAP004533) derives different functional properties in the G3 strain of the mosquito Anopheles gambiae(2012) Achinko, Daniel; Masiga, Dan; Mireji, Paul O; Catteruccia, FlaminiaCathepsin B is a lysosomal papain-like cysteine peptidase that is expressed in all tissues and functions primarily as an exopeptidase through its carboxydipeptidyl activity. Together with other cathepsins, it is involved in the degradation of proteins, proenzyme activation, antigen processing, metabolism and apoptosis. AGAP004533 is a cathepsin B peptidase of 337 amino acids known to be found on the mating plug. This plug is known to be produced in the male Anopheles gambiae mosquito and transferred to the female during mating [1]. The female digests this plug in 24 h. The protein is expressed in all life stages of the mosquito and in all tissues of the adult. We cloned and sequenced the protein in the larvae and pupae stages and all reproductive tissues (spermatheca, atria and ovary of the female; testes and male accessory glands (MAGs) of the male) of the G3 mosquito strain. These sequences were analysed with Geneious 5.5.5 and cLc workbench 6.6.1 software. Within the coding sequence, two single mutations at C584T (juvenile stages) and nucleotide A14T (ovary) were identified. The latter translates into a glutamine for leucine (Q6L), which causes the loss of the signal peptide due to loss of five amino acids at the N-terminal region of the protein sequence, meanwhile the former translates into an alanine for valine (A195V). Both mutations cause structural modifications within the secondary structure of the protein that eventually affect its 3D conformation. The sequences in the artria and spermatheca showed insertion of a cytosine at nucleotide 1010, which translates to a proline for a leucine (P337L) substitution, and hence loss of the stop codon at amino acid 338. This loss causes an extension of 14 amino acids at the carboxylic end of the protein, resulting in secondary structure modification. The sequence for the testes appeared transposed, and hence was not considered in the analysis. All the sequences translated on the same frame except for that of the ovary, which translated on a different frame. Protein BLAST of these sequences at NCBI using the blosum62 matrix, identified with AGAP004533 of Anopheles gambiae alongside other mosquito species, although that of the artria and spermatheca also identified with species of distant taxa such as Manduca sexta (FM957999.1) and Gallus gallus (NM205371.1). This relation was due to the amino acid extensions at the carboxylic end relating to parasite killing in the former, and embryonic apoptosis in the latter. Transcription factor predictions on all sequences identified equal binding sites (T00821, T00752), and that of the male accessory glands identified an extra binding site (T00360) known in humans as a bifunctional protein nuclear cytoplasmic O-N-acetylglucosaminidase and acetyltransferase. This site also has alternative splicing functions, which could be important for the variations observed in this gene. Sequence variations of this protein in the different stages and tissues of the mosquitoes may also be highly related to their functions and relative positions in the same or different biological processes within the various tissues. In-depth analysis of the reproductive role of AGAP004533 will help in reproductive control of the vectorItem Chemosensory receptors in tsetse flies provide link between chemical and behavioural ecology(2014) Masiga, Daniel; Obiero, George; Macharia, Rosaline; Mireji, Paul O; Christoffels, AlanTsetse flies survive in a variety of environments across tropical Africa, often rising to large numbers, despite their low birth rate of one offspring every seven to nine days. They use olfactory receptors to process chemical signals in their environments to find food, escape from predators, and locate suitable larviposition sites. We discuss the identification of odorant and gustatory receptors in Glossina morsitans morsitans and the role genomics could play in management of nuisance insectsItem Antimutagenic effect of Kenyan Tea cultivars in a bacterial test system(2014) Mbuthia, Karori; Wachira, Francis; Ngure, Raphael; Mireji, Paul O; Wachira, SabinaThe antimutagenic effects of the aqueous tea extracts from Kenyan black, green and purple cultivars were evaluated by the Ames te st using Salmonella typhimurium tester strains TA 1538. Results obtained showed that tea had no toxicity or mutagenic activity at a concentration of 20% (w/v) unlike the mut agen sodium azide. However, using the formulae, percentage inhibition = [1 - T/M] ×10 0 where T is number of revertants per plate in presence of mutagen and test sample and M is number of revertants per plate in positive control, tea extracts had a significant (P<0.05) antimutagenic activity where the percent inhibition was 65% for green te a, 38% for purple tea and 19.17% for black tea. This was attributed to the radical scavenging activity of polyphenols. There is need therefore to carry out further research to help understand the precise mechanism of action especially for black and purple teas, and to explore other beneficial effects that these polyphenols may have, before they can be adopted for therapeutic use.Item Larvicidal Activity of Selected Aloe Species Against Aedes aegypti (Diptera: Culiciade)(2014) Chore, Judith K; Obonyo, Meshack; Wachira, Francis N; Mireji, Paul OManagement of mosquito vectors by current classes of mosquitocides is relatively ineffective and necessitates prospecting for novel insecticides with different modes of action. Larvicidal activities of 15 crude extracts from three geographically isolated Aloe ngongensis (Christian), Aloe turkanensis (Christian), and Aloe fibrosa (Lavranos & L.E.Newton) (Xanthorrhoeaceae) species (five each) were evaluated against Aedes aegypti (Linnaeus in Hasselquist) (Diptera: Culiciade L.) yellow fever mosquito. Freshly collected leaves were separately shade-dried to constant weight at room temperature (25 ± 2°C) and powdered. Each powder was macerated in solvents of increasing polarity (hexane, chloroform, ethyl acetate, acetone, and methanol) for 72 h and subsequently filtered. Third-instar larvae (n = 25) of the mosquito were exposed to the extracts at different concentrations for 24 h to establish dose response relationships. All the fractions of A. ngongensis were active below 1 mg/ml except A. fibrosa and A. turkanensis. The highest activity (LC50) mg/ml was obtained with extracts of A. fibrosa hexane (0.05 [0.04–0.06]), followed by A. ngongensis hexane (0.11 [0.08–0.15]) and A. turkanensis ethyl acetate (0.11 [0.09–0.12]). The activities are apparently Aloe species specific and extraction solvent dependent. These findings suggest that extracts from selected Aloe species have mosquitocidal principles that can be exploited in development of new insecticides.Item RESEARCH Open Access High-resolution melting analysis reveals low Plasmodium parasitaemia infections among microscopically negative febrile patients in western Kenya(2014) Kipanga, Purity N; Omondi, David; Mireji, Paul O; Sawa, Patrick; Masiga, Daniel K; Villinger, JandouweBackground: Microscopy and rapid diagnostic tests (RDTs) are common tools for diagnosing malaria, but are deficient in detecting low Plasmodium parasitaemia. A novel molecular diagnostic tool (nPCR-HRM) that combines the sensitivity and specificity of nested PCR (nPCR) and direct PCR-high resolution melting analysis (dPCR-HRM) was developed. To evaluate patterns of anti-malarial drug administration when no parasites are detected, nPCR-HRM was employed to screen blood samples for low parasitaemia from febrile patients without microscopically detectable Plasmodium infections in a rural malaria-endemic setting. Methods: Blood samples (n = 197) were collected in two islands of Lake Victoria, Kenya, from febrile patients without Plasmodium detectable by microscopy or RDTs. 18S rRNA gene sequences were amplified from extracted DNA by nPCR-HRM, nPCR, and dPCR-HRM to detect and differentiate Plasmodium parasites. The limits of detection (LoD) were compared using serial dilutions of the WHO International Standard for P. falciparum DNA. Data on administration of anti-malarials were collected to estimate prescription of anti-malarial drugs to patients with and without low parasitaemia Plasmodium infections. Results: The coupled nPCR-HRM assay detected Plasmodium parasites with greater sensitivity (LoD = 236 parasites/mL) than either nPCR (LoD = 4,700 parasites/mL) or dPCR-HRM (LoD = 1,490 parasites/mL). Moreover, nPCR-HRM detected and differentiated low-parasitaemia infections in significantly greater proportions of patients than did either nPCR or dPCR-HRM (p-value <0.001). Among these low-parasitaemia infections, 67.7% of patients were treated with anti-malarials, whereas 81.5% of patients not infected with Plasmodium parasites were treated with anti-malarials. Conclusions: The enhanced sensitivity of nPCR-HRM demonstrates limitations of differential febrile illness diagnostics in rural malaria endemic settings that confound epidemiological estimates of malaria, and lead to inadvertent misadministration of anti-malarial drugs. This is the first study that employs low-parasitaemia Plasmodium diagnostics to quantify the prescription of anti-malarial drugs to both non-malaria febrile patients and patients with low-parasitaemia Plasmodium infections. nPCR-HRM enhances low-parasitaemia malaria diagnosis and can potentially surmount the deficiencies of microscopy and RDT-based results in determining low-parasitaemia Plasmodium infection rates for evaluating malaria elimination efforts. The findings highlight the need for improved differential diagnostics of febrile illness in remote malaria endemic regionsItem Polyphenolic composition and antioxidant activity of Kenyan Tea cultivars(2014) Karori, SM; Wachira, FN; Ngure, RM; Mireji, POPolyphenolic fractions in tea are potent bioactive mo lecules. In this study, the polyphenolic composition of 25 different types of Kenyan tea cultivars was de termined using the HPLC and the Folins Ciocalteus spectrophotometric methods. Total Polyphenols, Total Ca techins, individual catechins and Antioxidant Activity were significantly (P<0.05) different among tea varieties, with green tea had the highest levels of Total Polyphenols ranging from (19.70-26.12%), TC (8.51%-17.60%), indivi dual catechins, and AA (86.65-94.50%). In vitro bioassay carried out using 2, 2’-di phenyl picrylhydrazyl radical showed epigallocatechin gallate was the most potent catechin and the most potent in antioxidant activity (r=0.968***). Epigallocatechin (r=0.659***, p<0.001), Epicatechigallate (r=0.454*, p<0.001) and Epicatechin (EC) (r=0.780***, p<0.001) showed signifi cant (p<0.05) antioxidant activity. Black tea contained high levels of Theaflavins and Thear ubigins (2.072% to 17.12%), respectively) which accounted for its antioxidant activit y (r=0.803*** and r=0.859***, respectiv ely). Gallic acid also showed significant (r=0.530*) contribution to the antioxidant activity in black tea. Data obtained from this study reveals that different Kenyan tea cultivars have different polyphenolic co mposition which imparts on their unique biochemical qualities. Gr een and white tea products are rich in catechins, black tea products are rich in TFs and TRs while purple teas are rich in anthocyaninsItem Blood Meal Analysis and Virus Detection in Blood-Fed Mosquitoes Collected During the 2006–2007 Rift Valley Fever Outbreak in Kenya(2014) Lutomiah, Joel; Omond, David; Masiga, Daniel; Mutai, Collins; Mireji, Paul O; Ongus, Juliette; Linthicum, Ken J; Sang, RosemaryBackground: Rift Valley fever (RVF) is a zoonosis of domestic ruminants in Africa. Blood-fed mosquitoes collected during the 2006–2007 RVF outbreak in Kenya were analyzed to determine the virus infection status and animal source of the blood meals. Materials and Methods: Blood meals from individual mosquito abdomens were screened for viruses using Vero cells and RT-PCR. DNA was also extracted and the cytochrome c oxidase 1 (CO1) and cytochrome b (cytb) genes amplified by PCR. Purified amplicons were sequenced and queried in GenBank and Barcode of Life Database (BOLD) to identify the putative blood meal sources. Results: The predominant species in Garissa were Aedes ochraceus, (n=561, 76%) and Ae. mcintoshi, (n=176, 24%), and Mansonia uniformis, (n=24, 72.7%) in Baringo. Ae. ochraceus fed on goats (37.6%), cattle (16.4%), donkeys (10.7%), sheep (5.9%), and humans (5.3%). Ae. mcintoshi fed on the same animals in almost equal proportions. RVFV was isolated from Ae. ochraceus that had fed on sheep (4), goats (3), human (1), cattle (1), and unidentified host (1), with infection and dissemination rates of 1.8% (10/561) and 50% (5/10), respectively, and 0.56% (1/176) and 100% (1/1) in Ae. mcintoshi. In Baringo, Ma. uniformis fed on sheep (38%), frogs (13%), duikers (8%), cattle (4%), goats (4%), and unidentified hosts (29%), with infection and dissemination rates of 25% (6/24) and 83.3% (5/6), respectively. Ndumu virus (NDUV) was also isolated from Ae. ochraceus with infection and dissemination rates of 2.3% (13/561) and 76.9% (10/13), and Ae. mcintoshi, 2.8% (5/176) and 80% (4/5), respectively. Ten of the infected Ae. ochraceus had fed on goats, sheep (1), and unidentified hosts (2), and Ae. mcintoshi on goats (3), camel (1), and donkey (1). Conclusion: This study has demonstrated that RVFV and NDUV were concurrently circulating during the outbreak, and sheep and goats were the main amplifiers of these viruses respectively.