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Item A preliminary investigation of exposure to rabies virus in selected wildlife in the Kruger National Park, South Africa.(AOSIS, 2021-03-14) Rossouw, Leana; Boshoff, Carin; Sabeta, Claude; Kotzé, JohannRabies is a zoonotic disease caused by members of the genus Lyssavirus and causes fatal encephalitis in warm-blooded vertebrates. Rabies has been previously confirmed in domestic dog populations in close proximity to the Kruger National Park (KNP) and can potentially threaten conservation efforts. Domestic dogs infected with rabies virus occasionally enter the KNP and may be a source of rabies exposure to wildlife. Therefore, the aim of this study was to determine if wild carnivores in the KNP have been exposed to rabies virus, based on the presence of antibodies. Serum samples from the African wild dog (Lycaon pictus), spotted hyena (Crocuta crocuta), lion (Panthera leo), leopard (Panthera pardus) and banded mongoose (Mungos mungo) were tested for the presence of rabies-specific antibodies using the BioPro enzyme-linked immunoassay kit (BioPro ELISA kit). Selected sera were tested in parallel with the fluorescent antibody virus neutralisation test (FAVNT). Of the 168 carnivore serum samples screened, eight (4.8%) had a percentage blocking (PB) ≥ 40, indicating the presence of rabies-binding antibodies and confirmed with the FAVNT to be very low levels of rabies virus neutralising antibodies (range 0.00 IU/mL – 0.22 IU/mL). Rabies-binding antibodies detected by the BioPro ELISA kit and rabies virus neutralising antibodies shown by the FAVNT should however be interpreted with caution because of the lack of validation and species-specific cutoff values for wild carnivores. Conservation implications: The results of this study will assist in understanding the epidemiology of rabies in the KNP carnivores, especially exposure risk. The use of rabies diagnostic tools developed for domestic animals for disease surveillance in the KNP carnivores was also evaluated and the outcomes will further support research on rabies in free-ranging wildlife populations.Item Experimental infection of giraffe (Giraffa camelopardalis) with SAT-1 and SAT-2 foot-and-mouth disease virus.(Wiley, 2010-11-09) Vosloo, W.; Swanepoel, S.P.; Bauman, M.; Botha, B.; Esterhuysen, J.J.; Boshoff, C.I.; Keet, D.F.; Dekker, A.The potential role of giraffe (Giraffa camelopardalis) in the epidemiology and spread of foot-and-mouth disease (FMD) SAT types was investigated by experimental infection and detection of virus in excretions using virus isolation on primary pig kidney cell cultures. In two experiments separated by a period of 24 months, groups of four animals were needle infected with a SAT-1 or SAT- 2 virus, respectively and two in-contact controls were kept with each group. Viraemia was detected 3–9 days post-infection and virus isolated from mouth washes and faeces only occasionally up to day 13. The SAT-1 virus was transmitted to only one in-contact control animal, probably via saliva that contained virus from vesicles in the mouth of a needle-infected animal. None of the animals infected with the SAT-2 virus had any vesicles in the mouth, and there was no evidence of transmission to the in-contact controls. No virus was detected in probang samples for the duration of the experiments (60 days postinfection), indicating that persistent infection probably did not establish with either of these isolates. Giraffe most likely do not play an important role in FMD dissemination. Transmission of infection would possibly occur only during close contact with other animals when mouth vesicles are evident.Item Genome sequences of three African swine fever viruses of genotypes I, III, and XXII from South Africa and Zambia, isolated from ornithodoros soft ticks.(Microbiology Society, 2020-03-05) Ndlovu, S.; Williamson, A.L.; Malesa, R.; Van Heerden, J.; Boshoff, C.I.; Bastos, A.D.S; Heath, L.; Carulei, O.Here, we report the draft genome sequences of three African swine fever viruses isolated from Ornithodoros soft ticks. Isolates LIV 5/40 (Zambia), SPEC 57 (South Africa), and RSA/2/2008 (South Africa) belong to genotypes I, III, and XXII, respectively.Item Cassia abbreviata enhances glucose uptake and glucose transporter 4 translocation in C2C12 mouse skeletal muscle cells.(SAGE, 2021-01-21) Kamga-Simo-III, F. D. Y.; Kamatou, G.P.; Ssemakalu, C.; Shai, L.J.Background. This study aims at assessing C. abbreviata aqueous extracts for its potential to exhibit anti-diabetic activity in skeletal muscle cells. In addition to the toxicological and glucose absorption studies, the action of C. abbreviata extracts on some major genes involved in the insulin signaling pathway was established. Methods. The in vitro cytotoxic effects C. abbreviata was evaluated on muscle cells using the MTT assay and the in vitro glucose uptake assay conducted using a modified glucose oxidase method described by Van de Venter et al. (2008). The amount of GLUT-4 on cell surfaces was estimated quantitatively using the flow cytometry technique. Real time quantitative PCR (RT-qPCR) was used to determine the expression of GLUT-4, IRS-1, PI3 K, Akt1, Akt2, PPAR-g. Results. Cytotoxicity tests revealed that all extracts tested at various concentrations were nontoxic (LC50 > 5000). Aqueous extracts of leaves, bark and seeds resulted in a dose-dependent increase in glucose absorption by cells, after 1 h, 3 h and 6 h incubation period. Extracts of all three plant parts had the best effect after 3 h incubation, with the leaf extract showing the best activity across time (Glucose uptake of 29%, 56% and 42% higher than untreated control cells after treatment with 1 mg/ml extract at 1 h, 3 h and 6 h, respectively). All extracts, with the exception 500 mg/ml seed extract, induced a two-fold increase in GLUT-4 translocation while marginally inducing GLUT-10 translocation in the muscle cells. The indirect immunofluorescence confirmed that GLUT-4 translocation indeed occurred. There was an increased expression of GLUT-4, IRS1 and PI3 K in cells treated with insulin and bark extract as determined by the RT-qPCR. Conclusion. The study reveals that glucose uptake involves GLUT-4 translocation through a mechanism that is likely to involve the upstream effectors of the PI3-K/Akt pathway.