Cannon B.J.,Khalifa University |
Ruto Pkalya D.,Kisii University
Terrorism and Political Violence | Year: 2017
This article questions the current narrative paradigm and argues that al-Shabaab attacks Kenya for strategic and highly rational reasons, beyond sharing a border and having bases in southern Somalia closer to major population centres than Ethiopia or Uganda. Al-Shabaab targets Kenya more than other frontline states because of the opportunity spaces linked to Kenya’s international status and visibility, its relatively free and independent media that widely publicizes terrorist attacks, a highly developed and lucrative tourist sector that provides soft targets, the comparatively high number of Kenyan foreign fighters within the group’s ranks, the presence of terror cells in Kenya, expanding democratic space, and high levels of corruption. These variables play into al-Shabaab’s motivations and aid planning and execution of terrorist acts that aim to fulfil the group’s quest to survive by maintaining relevance. In order to address this predictable menace, we offer a number of measures that Kenya needs to take, including reducing corruption in order to properly invest in intelligence efforts and relevant homeland security measures, thereby making it possible for Kenya to sustainably and effectively combat al-Shabaab. © 2017 Taylor & Francis
Green tea proanthocyanidins cause impairment of hormone-regulated larval development and reproductive fitness via repression of juvenile hormone acid methyltransferase, insulin-like peptide and cytochrome P450 genes in Anopheles gambiae sensu stricto
Muema J.M.,Jomo Kenyatta University of Agriculture and Technology |
Nyanjom S.G.,Jomo Kenyatta University of Agriculture and Technology |
Mutunga J.M.,Malaria Research Programme |
Njeru S.N.,Kisii University |
And 3 more authors.
PLoS ONE | Year: 2017
Successful optimization of plant-derived compounds into control of nuisance insects would benefit from scientifically validated targets. However, the close association between the genotypic responses and physiological toxicity effects mediated by these compounds remains underexplored. In this study, we evaluated the sublethal dose effects of proanthocyanidins (PAs) sourced from green tea (Camellia sinensis) on life history traits of Anopheles gambiae (sensu stricto) mosquitoes with an aim to unravel the probable molecular targets. Based on the induced phenotypic effects, genes selected for study targeted juvenile hormone (JH) biosynthesis, signal transduction, oxidative stress response and xenobiotic detoxification in addition to vitellogenesis in females. Our findings suggest that chronic exposure of larval stages (L3/L4) to sublethal dose of 5 ppm dramatically extended larval developmental period for up to 12 days, slowed down pupation rates, induced abnormal larval-pupal intermediates and caused 100% inhibition of adult emergence. Further, females exhibited significant interference of fecundity and egg hatchability relative to controls (p < 0.001). Using reverse transcription quantitative polymerase chain reaction (RTqPCR), our findings show that PA-treated larvae exhibited significant repression of AgamJHAMT (p < 0.001), AgamILP1 (p < 0.001) and AgamCYP6M2 (p < 0.001) with upregulation of Hsp70 (p < 0.001). Females exposed as larvae demonstrated down-regulation of AgamVg (p = 0.03), AgamILP1 (p = 0.009), AgamCYP6M2 (p = 0.05) and AgamJ-HAMT (p = 0.02). Our findings support that C. sinensis proanthocyanidins affect important vectorial capacity components such as mosquito survival rates and reproductive fitness thus could be potentially used for controlling populations of malaria vectors. © 2017 Muema et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Njeru S.N.,Kisii University |
Njeru S.N.,Leibniz Institute for Age Research |
Obonyo M.A.,Egerton University |
Nyambati S.O.,Egerton University |
Ngari S.M.,Egerton University
BMC Complementary and Alternative Medicine | Year: 2015
Background: Premna resinosa (Hochst.) Schauer also called "mukarakara" in Mbeere community of Kenya is used in the management of respiratory illness. In this study we investigated antituberculous, antifungal, antibacterial activities including cytotoxicity and phytochemical constituents of this plant. Methods: Antibacterial and antifungal activities were investigated by disc diffusion and micro dilution techniques. Antituberculous activity was investigated using BACTEC MGIT 960 system while cytotoxicity was analyzed by MTT assay on Vero cells (Methanolic crude extract) and HEp-2 cells (fractions). Finally, phytochemicals were profiled using standard procedures. Results: P. resinosa had high antituberculous activity with a MIC of <6.25μg/ml in ethyl acetate fraction. The antibacterial activity was high and broad spectrum, inhibiting both Gram positive and Gram negative bacteria. Dichloromethane fraction had the best antibacterial MIC of 31.25μg/ml against Methicillin-resistant S. aureus while Ethyl acetate fraction had the highest zone of inhibition of 22.3 ± 0.3 against S. aureus. Its effects on tested fungi were moderate with petro ether fraction giving an inhibition of 10.3 ± 0.3 on C. albicans. The crude extract and two fractions (petro ether and methanol) were not within the acceptable toxicity limits, however dichloromethane and ethyl acetate fractions that exhibited higher activity were within the acceptable toxicity limit (CC50 < 90). The activity can to some extent be associated to alkaloids, flavonoids, terpenoids, anthraquinones and phenols detected in this plant extracts. Conclusion: Our findings demonstrate that P. resinosa has high selective potential as a source of novel lead for antituberculous, antibacterial and antifungal drugs. Of particular relevance is high activity against MRSA, S. aureus, C. albicans and MTB which are great public health challenge due to drug resistance development and as major sources of community and hospital based infections. © 2015 Njeru et al.
PubMed | Ecole Superieure dAgricultuResearch Institute, Jomo Kenyatta University of Agriculture and Technology and Kisii University
Type: Journal Article | Journal: BMC complementary and alternative medicine | Year: 2016
Vector control remains the mainstay to effective malaria management. The negative implications following persistent application of synthetic insecticides geared towards regulation of mosquito populations have necessitated prospection for ecofriendly effective chemistries. Plant-derived compounds have the potential to control malaria-transmitting mosquito populations. Previously, Agerantum conyzoides extracts have demonstrated toxicity effects on disease-transmitting mosquitoes. However, their efficacy in controlling Afrotropical malaria vectors remains unclear. Herein, the toxicity and growth disruption activities of crude methanolic leaf extract of A. conyzoides on Anopheles gambiae sensu stricto and An. arabiensis larvae were assessed.Late third (L3) instars of An. gambiae s.s and An. arabiensis larvae were challenged with increasing doses of crude methanolic extract of A. conyzoides. The larval mortality rates were recorded every 24h and the LCTreatment of larvae with the methanolic extract depicted dose-dependent effects with highest mortality percentages of69% observed when exposed with 250ppm and 500ppm for 48h while growth disruption effects were induced by sublethal doses of between 50-100ppm for both species. Relative to experimental controls, the extract significantly reduced larval survival in both mosquito species (ANOVA, FThe extract displayed considerable larvicidal activity and inhibited emergence of adult mosquitoes relative to experimental controls, a phenomenon probably associated with induced developmental hormone imbalance. Optimization of the bioactive compounds could open pathways into vector control programmes for improved mosquito control and reduced malaria transmission rates.
Agency: European Commission | Branch: H2020 | Program: CSA | Phase: WASTE-4b-2014 | Award Amount: 1.64M | Year: 2015
Urbanization is on the rise in Africa and this trend is expected to continue in the future. The fast growing use of technology is creating a rising e-waste stream, for which there is limited recycling capacity. Waste management infrastructures and public awareness of the health issues is largely non-existent. Basic environmental precautions are almost absent and health and safety regulations are loosely enforced. Improvements are therefore urgently needed to combat related health issues, alleviate poverty and develop the local recycling sector. EWIT projects aim is to address these challenges, assisting African municipalities in the implementation of effective e-waste management systems for their communities. The project will develop a comprehensive mapping of the baseline data of African metropolitan areas related to e-waste management, analyzing the most relevant experiences, processes and legal tools available. It will then deliver a dynamic and easy to use information and service portal to offer guidance and practical support for the design and development of e-waste collection and recycling systems. EWIT will generate the expected impacts through 5 coordinated work packages. The working model is based on two different set of workshops, one led by Cities and the other by Experts. Tools, implementation models, policies and procedures will feed a dedicated information and service platform called E-waste implementation toolkit. This dynamic and easy to use internet portal will be a strategic source of knowledge for decision makers at industry and local government level. Dissemination will play a key role to assure that the projects deliverables are well understood and ready to be applied. EWIT will define the conditions and actions necessary to implement effective waste recycling systems in metropolitan areas, increasing recycling opportunities for entrepreneurs, generating new jobs and improving environment and health protection of local communities.
Candaele J.,Vlaams Institute for Biotechnology |
Candaele J.,Ghent University |
Demuynck K.,Vlaams Institute for Biotechnology |
Demuynck K.,Ghent University |
And 8 more authors.
Plant Physiology | Year: 2014
DNA methylation is an important and widespread epigenetic modification in plant genomes, mediated by DNA methyltransferases (DMTs). DNA methylation is known to play a role in genome protection, regulation of gene expression, and splicing and was previously associated with major developmental reprogramming in plants, such as vernalization and transition to flowering. Here, we show that DNA methylation also controls the growth processes of cell division and cell expansion within a growing organ. The maize (Zea mays) leaf offers a great tool to study growth processes, as the cells progressively move through the spatial gradient encompassing the division zone, transition zone, elongation zone, and mature zone. Opposite to de novo DMTs, the maintenance DMTs were transcriptionally regulated throughout the growth zone of the maize leaf, concomitant with differential CCGG methylation levels in the four zones. Surprisingly, the majority of differentially methylated sequences mapped on or close to gene bodies and not to repeat-rich loci. Moreover, especially the 59 and 39 regions of genes, which show overall low methylation levels, underwent differential methylation in a developmental context. Genes involved in processes such as chromatin remodeling, cell cycle progression, and growth regulation, were differentially methylated. The presence of differential methylation located upstream of the gene anticorrelated with transcript expression, while gene body differential methylation was unrelated to the expression level. These data indicate that DNA methylation is correlated with the decision to exit mitotic cell division and to enter cell expansion, which adds a new epigenetic level to the regulation of growth processes. © 2014 American Society of Plant Biologists. All rights reserved.
PubMed | University of Dschang, Johannes Gutenberg University Mainz, University of Khartoum, University of Nairobi and Kisii University
Type: | Journal: Journal of ethnopharmacology | Year: 2016
Plants from Kenyan flora are traditionally used against many ailments, including cancer and related diseases. Cancer is characterized as a condition with complex signs and symptoms. Recently there are recommendations that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account when selecting plants that treat cancer.The present study was aimed at investigating the cytotoxicity of a plethora of 145 plant parts from 91 medicinal plants, most of which are used in the management of cancer and related diseases by different communities in Kenya, against CCRF-CEM leukemia cell line.Extracts from different plant parts (leaves, stems, stem bark, roots, root barks, aerial parts and whole herb) were obtained by cold percolation using different solvent systems, such as (1:1v/v) dichloromethane (CH2Cl2) and n-hexane (1), methanol (MeOH) and CH2Cl2 (2); neat MeOH (3), 5% H2O in MeOH (4) and with ethanol (EtOH, 5); their cytotoxicities were determined using the resazurin reduction assay against CCRF-CEM cells.At a single concentration of 10g/mL, 12 out of 145 extracts exhibited more than 50% cell inhibition. These include samples from the root bark of Erythrina sacleuxii (extracted with 50% n-hexane-CH2Cl2), the leaves of Albizia gummifera, and Strychnos usambarensis, the stem bark of Zanthoxylum gilletii, Bridelia micrantha, Croton sylvaticus, and Albizia schimperiana; the root bark of Erythrina burttii and E. sacleuxii (extracted with 50% CH2Cl2-MeOH), the stem bark of B. micrantha and Z. gilletii (extracted using 5% MeOH-H2O) and from the berries of Solanum aculeastrum (extracted with neat EtOH). The EtOH extract of the berries of S. aculeastrum and A. schimperiana stem bark extract displayed the highest cytotoxicity towards leukemia CCRF-CEM cells, with IC50 values of 1.36 and 2.97g/mL, respectively. Other extracts having good activities included the extracts of the stem barks of Z. gilletii and B. micrantha and leaves of S. usambarensis with IC50 values of 9.04, 9.43 and 11.09g/mL, respectively.The results of this study provided information related to the possible use of some Kenyam medicinal plants, and mostly S. aculeastrum, A. schimperiana, C. sylvaticus, Z. gilletii, B. micrantha and S. usambarensis in the treatment of leukemia. The reported data helped to authenticate the claimed traditional use of these plants. However, most plants are used in combination as traditional herbal concoctions. Hence, the cytotoxicity of corresponding plant combinations should be tested in vitro to authenticate the traditional medical practitioners actual practices.
Aming'a N.N.,Kisii University
Interdisciplinary Journal of Information, Knowledge, and Management | Year: 2015
Knowledge management and knowledge assets have gained much prominence in recent years and are said to improve organizational performance. Knowledge capture and acquisition mechanisms enhance organizational memory and performance. However, knowledge capture and acquisition mechanisms in higher education institutions are not well known. The aim of this study was to investigate the knowledge capture and acquisition mechanisms at Kisii University. This was a case study in which data were collected through interviews and questionnaires. Purposive sampling was used to determine interview participants while questionnaire respondents were selected through stratified random sampling. Qualitative and quantitative data were analysed using SPSS® student version 14; it revealed that there were various knowledge capture and acquisition mechanisms at Kisii University. It was also established that the University encountered various challenges in knowledge capture and acquisition and lacked some essential knowledge capture and acquisition mechanisms. In this regard, this study proposed knowledge capture and acquisition guidelines that may be adopted by the University to enhance its organizational memory and performance.
Musyoki S.,Kisii University |
Mining S.,Moi University |
Nyongesa P.,Moi University
Interdisciplinary Perspectives on Infectious Diseases | Year: 2014
Background. To date the effect of pregnancy on the immune activation of CD8 T cells that may affect HIV disease progression has not been well studied and remains unclear. Objective. To determine the effect of pregnancy on CD8 T lymphocyte activation and its relationship with CD4 count in HIV infected pregnant women. Study Design. Case control. Study Site. AMPATH and MTRH in Eldoret, Kenya. Study Subjects. Newly diagnosed asymptomatic HIV positive pregnant and nonpregnant women with no prior receipt of antiretroviral medications. Study Methods. Blood samples were collected from the study participants and levels of activated CD8 T lymphocytes (CD38 and HLA-DR) were determined using flow cytometer and correlated with CD4 counts of the study participants. The descriptive data focusing on frequencies, correlation, and cross-tabulations was statistically determined. Significance of the results was set at P < 0.05. Results. HIV positive pregnant women had lower activated CD8 T lymphocyte counts than nonpregnant HIV positive women. Activated CD8 T lymphocyte counts were also noted to decrease in the second and third trimesters of pregnancy. Conclusion. Pregnancy has a significant suppression on CD8+ T lymphocyte immune activation during HIV infections. Follow-up studies with more control arms could confirm the present study results. © 2014 Stanslaus Musyoki et al.
PubMed | Kisii University
Type: | Journal: BMC research notes | Year: 2016
Intestinal parasitic infections are a major health problem worldwide. In Kenya intestinal parasitic infections are highly prevalent especially in prisons due to poor and/or inadequate infrastructure. The aim of this study was to establish the risk factors associated with intestinal parasites infection among inmates of Kisii prison, Kisii county, Kenya.Fresh stool samples of 384 inmates in Kisii prison aged 20years and above, were screened for intestinal parasitic infections between February and August 2015. Stool samples were processed using direct fecal smear and formol-ether sedimentation techniques for confirmation then they were examined microscopically. Multiple logistic regression analysis was used to establish the relationship of various factors and practices with the occurrence of intestinal parasites. The differences were considered statistically significant at P<0.05.Of the 384 inmates screened, 95 (24.7%) were infected with one or more intestinal parasites. Of the positive inmates, 58 (15.1%) were infected with one species of protozoa while 24 (5.2%) were infected with at least one species of helminthes and 13 (3.5%) had mixed infections of species of intestinal parasites. Washing of hands before meals and after visiting toilets significantly reduced risk of infections (P<0.05). The level of education was inversely related to the risk of intestinal parasites infection where by inmates at post primary education were least infected with intestinal parasites infection as compared to unschooled inmates (P<0.05). Wearing of shoes was seen to significantly reduce parasitic infections (P0.05). Duties assigned to inmates did not significantly determine the risk of intestinal parasitic infection (P>0.05). Male inmates had significantly more intestinal parasites infections 57 (21.8%) compared to females 28 (8.1%) (P<0.05). Inmates within ages 20-29years were more infected (11.3%) compared to the age group of>60years (0.6%) (P<0.05). There was no statistical significant difference between the number of infections among the length of the jail terms (P<0.05).Prevalence of intestinal parasites was high among inmates in the study area than the general population. Practices like wearing of shoes, washing of hands before meals after visiting a toilet and level of education affect the spread of the infections.