Browsing by Author "Onanyang, David"

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    Dietary Restriction Induces a Stable Metabolic Obesity Phenotype in Drosophila Melanogaster
    (Research Square, 2021) Asiimwe, Oscar Hilary; Oluwadare Sulaiman, Sheu; Ochieng, Juma John; Onanyang, David; Obado Osuwat, Lawrence; Ndinawe, John Mark; Omachonu Okpanachi, Alfred; Kasozi, Keneth Iceland
    Challenges associated with current nutritional models to induce obesity in Drosophila melanogaster created a rationale for this study. The objective of the study was to investigate biochemical changes associated with high-fat diet (HFD), high sucrose diet (HSD), and a protein-restricted diet (DR) to induce a healthy metabolic obesity state. Drosophila melanogaster were fed to four experimental diets: regular food (control), HFD, HSD, and DR, for four weeks. Peristaltic waves were measured on 3rd instar larvae, while negative geotaxis, body mass, catalase activity; and total triglycerides, sterol, and protein were measured in adult Drosophila melanogaster. Results DR produced a Drosophila melanogaster phenotype which had superior adaptive advantages than that generated from HFD and HSD. HFD was the best phenotype during larval stages; however, locomotory, body mass, triglyceride, sterol concentrations, and catalase activity were highest in the DR phenotype during adulthood. High catalase activity and high triglyceride content demonstrated a balanced and healthy metabolic obesity status than in other phenotypes in the adult stage. Evolutionary changes are responsible for the selective advantage of the DR phenotype over the HFD phenotype. Prospective studies to guide therapy and community behavior should place more emphasis on the DR phenotypes in Drosophila melanogaster.
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    Epidemiology of Trypanosomiasis in Wildlife—Implications for Humans at the Wildlife Interface in Africa
    (Frontiers in Veterinary Science, 2021) Kasozi, Keneth Iceland; Zirintunda, Gerald; Ssempijja, Fred; Buyinza, Bridget; Matama, Kevin; Nakimbugwe, Helen N.; Onanyang, David; Bogere, Paul; Ochieng, Juma John; Matovu, Wycliff; Nalumenya, David Paul; Batiha, Gaber El-Saber; Osuwat, Lawrence Obado; Omadang, Leonard; Welburn, Susan Christina
    While both human and animal trypanosomiasis continue to present as major human and animal public health constraints globally, detailed analyses of trypanosome wildlife reservoir hosts remain sparse. African animal trypanosomiasis (AAT) affects both livestock and wildlife carrying a significant risk of spillover and cross-transmission of species and strains between populations. Increased human activity together with pressure on land resources is increasing wildlife–livestock–human infections. Increasing proximity between human settlements and grazing lands to wildlife reserves and game parks only serves to exacerbate zoonotic risk. Communities living and maintaining livestock on the fringes of wildlife-rich ecosystems require to have in place methods of vector control for prevention of AAT transmission and for the treatment of their livestock. Major Trypanosoma spp. include Trypanosoma brucei rhodesiense, Trypanosoma brucei gambiense, and Trypanosoma cruzi, pathogenic for humans, and Trypanosoma vivax, Trypanosoma congolense, Trypanosoma evansi, Trypanosoma brucei brucei, Trypanosoma dionisii, Trypanosoma thomasbancrofti, Trypanosma elephantis, Trypanosoma vegrandis, Trypanosoma copemani, Trypanosoma irwini, Trypanosoma copemani, Trypanosoma gilletti, Trypanosoma theileri, Trypanosoma godfreyi, Trypansoma simiae, and Trypanosoma (Megatrypanum) pestanai. Wildlife hosts for the trypansomatidae include subfamilies of Bovinae, Suidae, Pantherinae, Equidae, Alcephinae, Cercopithecinae, Crocodilinae, Pteropodidae, Peramelidae, Sigmodontidae, and Meliphagidae. Wildlife species are generally considered tolerant to trypanosome infection following centuries of coexistence of vectors and wildlife hosts. Tolerance is influenced by age, sex, species, and physiological condition and parasite challenge. Cyclic transmission through Glossina species occurs for T. congolense, T. simiae, T. vivax, T. brucei, and T. b. rhodesiense, T. b. gambiense, and within Reduviid bugs for T. cruzi. T. evansi is mechanically transmitted, and T. vixax is also commonly transmitted by biting flies including tsetse. Wildlife animal species serve as long-term reservoirs of infection, but the delicate acquired balance between trypanotolerance and trypanosome challenge can be disrupted by an increase in challenge and/or the introduction of new more virulent species into the ecosystem. There is a need to protect wildlife, animal, and human populations from the infectious consequences of encroachment to preserve and protect these populations. In this review, we explore the ecology and epidemiology of Trypanosoma spp. in wildlife.
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    High insecticide resistances levels in Anopheles gambiaes s.l. in northern Uganda and its relevance for future malaria control
    (BMC research notes, 2020) Echodu, Richard; Iga, Julius; Oyet, William Samuel; Mireji, Paul; Anena, Juliet; Onanyang, David; Iwiru, Tereza; Lutwama, Julius Julian; Auma Opiyo, Elizabeth
    The aim of the study was to determine the level of insecticide resistance and diversity in Anopheles mosquitoes in northern Uganda. Standard WHO insecticide susceptibility test assays were used to test for susceptibility to 0.5% malathion, 0.1% bendiocarb, 0.05% deltamethrin and 0.75% permethrin on 3–5 day old generation one progeny. We also screened for species diversity and knockdown resistance using PCR assay. Results: Anopheles gambiae s.s. is the predominant malaria vector in northern Uganda followed by An. arabiensis. An. gambiae s.s. was susceptible to malathion and bendiocarb with the observed mortality rate of 100% and 98–100% observed respectively while very high resistance was observed with deltamethrin and permethrin. Minimal KDReastern variant homozygous forms of 8.3% in An. gambiae s.s. were detected in Oyam district. In conclusion, this study confirms that An. gambiae s.s. females are susceptible to malathion and bendiocarb while high intensity of resistance was observed with deltamethrin and permethrin in the same area. Use of carbamate and organophosphate insecticides bendiocarb and malathion for indoor residual spraying activities in northern Uganda is highly recommended since high levels of pyrethroids resistance (deltamethrin and permethrin) was detected in the area.