Browsing by Author "Mgode, G. F."
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Item Accuracy of giant African pouched rats for diagnosing tuberculosis: comparison with culture and Xpert W MTB/RIF(Researchgate) Mulder, C.; Mgode, G. F.; Ellis, H.; Valverde, E.; Beyene, N.; Cox, C.; Reid, S. E.; Van’t Hoog, A. H.; Edwards, T. L.Item Application of a multidisciplinary approach to the systematics of Acomys (Rodentia: Muridae) from Northern Tanzania(2006-12) Mgode, G. F.The systematic status and geographic distribution of spiny mice of the genus Acomys I. Geoffroy, 1838 in Northern Tanzania is uncertain. This study assesses the systematic and geographic distribution of Acomys from Northern Tanzania using a multidisciplinary approach that includes molecular, cytogenetic, traditional and geometric morphometric analyses, and classical morphology of the same individuals. The molecular analysis was based on 1140 base pairs (bp) of the mitochondrial cytochrome b and 1297 bp of the nuclear interphotoreceptor retinoid binding protein (IRBP) gene sequences. These data were subjected to phylogenetic analyses using Maximum likelihood, Bayesian, Maximum parsimony, and Minimum evolution analyses. The cytogenetic analysis included G-banding of metaphase chromosomes. The morphometric analyses included univariate and multivariate analyses of traditional morphometric measurements of the cranium and mandible, and of geometric morphometric two-dimensional landmarks of the dorsal, ventral, and lateral views of the cranium, and lateral view of mandible that included thinplate spline (TPS) analysis. The classical morphology included examination of external, cranial and mandibular morphology. Results of all these multidisciplinary analyses were congruent and provide evidence for the occurrence of two sympatric species of Acomys in northern Tanzania, namely, the previously recorded A. wilsoni (2n = 62) and a newly recorded A. cf. percivali (2n = 58). These results that also represent the first reported mitochondrial cytochrome b and nuclear IRBP gene sequences and karyotype for A. cf. percivali, increases the number of species known to occur in Tanzania from four to five. However, the mitochondrial cytochrome b data that included GenBank sequences from the type locality in Kenya suggest that A. wilsoni may not be monophyletic. Ecologically, the two species seem to partition their niches with A. cf. percivali being found in well-covered habitats with thorn bushes, rocky and mountainous areas, and A. wilsoni being found in open semi-arid grasslands as well as in rice fields. The two species appear to be isolated by complex natural barriers formed by the Great East African Rift Valley whose geological features have generally been associated with active rodent speciation. However, the present results need further multidisciplinary investigation involving extensive sampling and examination of topotypical material.Item Challenges in determining the pathogenicity status of Leptospira isolates with phenotypic methods: The need for a polyvalent approachMgode, G. F.; Machang’u, R. S.; Collares-Pereira, M.; Vieira, M. L.; Goris, M. G. A.; Engelbert, M.; Hartskeerl, R. A.Item Challenges in determining the pathogenicity status of Leptospira isolates with phenotypic methods: The need for a polyvalent approach(2010-12-04) Mgode, G. F.; Machang’u, R. S.; Collares-Pereira, M.; Vieira, M. L.; Goris, M. G. A.; Engelbert, M.; Hartskeerl, R. A.Understanding the pathogenic status of leptospires, the causative agents of leptospirosis, is important for successful laboratory diagnosis and control programmes of this zoonosis. Leptospires are difficult to differentiate morphologically; therefore, their pathogenic, intermediate or saprophytic status is currently determined based on both phenotypic tests like growth response in medium containing 8-azaguanine and growth at low temperature (13°C), and genotypic methods. The present study reports on the pathogenic versus saprophytic characterization of nine Leptospira isolates from animal hosts (rodents and dogs) and humans, with specific interest on a canine isolate coded “Dog109”, which showed an ambiguous or intermediate status according to conventional (phenotypic) and molecular (genotypic) tests. The results strongly indicate the need of a polyvalent analytical approach for improving the differentiation of the pathogenic status of circulating serovars,Item Effectiveness of the domestic cat (Felis silvestris catus) urine extracts odour against commensal rodents(COSTECH) Mulungu, L. S.; Ngowo, V.; Mdangi, M. E.; Magadula, A. J. J.; Kapingu, M.; Mbukwa, E.; Mgina, C. A.; Mwatawala, M. W.; Kichuki, M.; Mwakalobo, A. S.; Mgode, G. F.Item Effectiveness of the Domestic Cat (Felis silvestris catus) Urine Extracts Odour against Commensal Rodents(Huria Journal) Mulungu, L. S.; Ngowo, V.; Mdangi, M. E.; Magadula, A. J. J.; Kapingu, M.; Mbukwa, E.; Mgina, C. A.; Mwatawala, M. W.; Kichuki, M.; Mwakalobo, A. S.; Mgode, G. F.Item Effectiveness of the domestic cat (Felis silvestris catus) urine extracts odour against commensal rodents(COSTECH, 2017) Mulungu, L. S.; Ngowo, V.; Mdangi, M. E.; Magadula, A. J. J.; Kapingu, M.; Mbukwa, E.; Mgina, C. A.; Mwatawala, M. W.; Kichuki, M.; Mwakalobo, A. S.; Mgode, G. F.The aim of this study was to investigate the effects of an extract of cat urine odour as a repellant of commensal rodents in houses. Cat urine was drawn and stored frozen in universal bottles at -20 0 C until use. The stored cat urine was then thawed and mixed with maize starch to form a thick dough and then granulated and dried at room temperature before being packed in a hermetically closed jar. Initially, rodent foot marks on tracking soot coat tiles were used to estimate the rat population before the cat urine extracts application. Twenty households with high and low rodent activities were selected purposively in the study area. Ten houses were treated with the urine extracts and ten others were kept untreated (control). Both treated and untreated houses were categorized at two levels (i.e. low and high rodent activities) as determined by the tracking tile foot prints. One tracking tile was placed in each of the selected houses and rodent foot marks were counted. Collected data were subjected to analysis of variance and the results showed a significant difference in rodent activities which however, depended on the sex of the cat that donated the urine base. Female cat urine extract repelled significantly more commensal rodents as compared to male cat urine extract. The repellent effect was observed from day 1 to 4; but not beyond. Our findings suggest that cat urine odour has the potential to repel commensal rodent pest species; with female cat urine being more effective than male cat urine.Item From pests to tests: training rats to diagnose tuberculosis(ERS 2020) Fiebig, L.; Beyene, N.; Burny, R.; Fast, C. D.; Cox, C.; Mgode, G. F.Item From pests to tests: training rats to diagnose tuberculosis(ERS 2020, 2020) Fiebig, L.; Beyene, N.; Burny, R.; Fast, C. D.; Cox, C.; Mgode, G. F.2020 is the year of the rat. The rat is the first of the 12 Chinese zodiac signs, and represents spirit, alertness, flexibility and vitality. In respiratory medicine, we may think of rats as vectors for diseases, such as pulmonary forms of hantavirus disease or leptospirosis, and pneumonic plague. Rodent control is thus part of hygiene guidelines and the International Health Regulations. And yet, the rat’s keen sense of smell has led to its incredible career as a living tuberculosis (TB) detector. The TB detection rat journey began with an idea in Tanzania in 2001, roughly 120 years after the TB-causing Mycobacterium tuberculosis was discovered by microscopy and bacterial culture. African giant pouched rats (Cricetomys ansorgei) had already been successfully trained using positive reinforcement to find explosives [1]. So, the question arose if they could do more for humanity by helping to also combat disease. But how would the rats use their noses to find bacteria or otherwise sniff out TB patients? For centuries, olfaction had already informed diagnostics in medical practices, e.g. in detecting metabolic issues such as ketoacidosis or tissue decay such as gangrene [2]. In the Flemish common language, the word tering, which etymologically refers to the smell of tar, is used for TB. The advent of chromatographic techniques allows characterisation of the organic compounds causing odours.Item Leptospirosis in sugarcane plantation and fishing communities in Kagera northwestern Tanzania(PLOS/ Neglected Tropical Diseases) Mgode, G. F.; Japhary, M. M.; Mhamphi, G. G.; Kiwelu, I.; Athaide, I.; Machang’u, R. S.Item Mycobacterium genotypes in pulmonary tuberculosis infections and their detection by trained African giant pouched rats(Springer Science+Business) Mgode, G. F.; Cohen-Bacrie, S.; Bedotto, M.; Weetjens, B. J.; Cox, C.; Jubitana, M.; Kuipers, D.; Machang’u, R. S.; Kazwala, R.; Mfinanga, S.G.; Kaufmann, S. H. E.; Drancourt, M.Item Mycobacterium genotypes in pulmonary tuberculosis infections and their detection by trained African giant pouched rats(Springer Science+Business, 2015) Mgode, G. F.; Cohen-Bacrie, S.; Bedotto, M.; Weetjens, B. J.; Cox, C.; Jubitana, M.; Kuipers, D.; Machang’u, R. S.; Kazwala, R.; Mfinanga, S.G.; Kaufmann, S. H. E.; Drancourt, M.Tuberculosis (TB) diagnosis in low-income countries is mainly done by microscopy. Hence, little is known about the diversity of Mycobacterium spp. in TB infections. Different genotypes or lineages of Mycobacte- rium tuberculosis vary in virulence and induce different inflammatory and immune responses. Trained Cricetomys rats show a potential for rapid diagnosis of TB. They detect over 28 % of smear-negative, culture-positive TB. How- ever, it is unknown whether these rats can equally detect sputa from patients infected with different genotypes of M. tuberculosis. A 4-month prospective study on diversity of Mycobacterium spp. was conducted in Dar es Salaam, Tanzania. 252 sputa from 161 subjects were cultured on Lowenstein-Jensen medium and thereafter tested by rats. Mycobacterial isolates were subjected to molecular iden- tification and multispacer sequence typing (MST) to determine species and genotypes. A total of 34 Mycobac- terium spp. isolates consisting of 32 M. tuberculosis, 1 M. avium subsp. hominissuis and 1 M. intracellulare were obtained. MST analyses of 26 M. tuberculosis isolates yielded 10 distinct MST genotypes, including 3 new genotypes with two clusters of related patterns not grouped by geographic areas. Genotype MST-67, shared by one- third of M. tuberculosis isolates, was associated with the Mwananyamala clinic. This study shows that diverse M. tuberculosis genotypes (n = 10) occur in Dar es Salaam and trained rats detect 80 % of the genotypes. Sputa with two M. tuberculosis genotypes (20 %), M. avium homin- issuis and M. intracellulare were not detected. Therefore, rats detect sputa with different M. tuberculosis genotypes and can be used to detect TB in resource-poor countries.Item Mycobacterium tuberculosis volatiles for diagnosis of tuberculosis by Cricetomys rats(Elsevier) Mgode, G. F.; Weetjens, B.; Nawrath, T.; Lazar, D.; Cox, C.Item Pattern of ovulation in an ancient, solitary mole-rat lineage: Heliophobius argenteocinereus emini from Tanzania(CORNELL UNIVERSITY) Katandukila, J. V.; Ngalameno, M. K.; Mgode, G. F.; Bastos, A. D. S.; Bennett, N. C.Item Pattern of ovulation in an ancient, solitary mole-rat lineage: Heliophobius argenteocinereus emini from Tanzania(CORNELL UNIVERSITY, 2017) Katandukila, J. V.; Ngalameno, M. K.; Mgode, G. F.; Bastos, A. D. S.; Bennett, N. C.Heliophobius is an ancient subterranean rodent lineage within the family Bathyergidae, that displays seasonal breeding over a broad geographical range. In East Africa, reproduction in these solitary mole-rats has been shown to coincide with the long rains, but it is not clear whether Heliophobius argenteocinereus emini (Noack 1894) from Tanzania is an induced or spontaneous ovulator. To address this, urinary progesterone was measured every second day over a period of 132 days in six wild-caught females subjected to three sequential experimental treatments. In the first, control (C) treatment, females were housed singly for a period of 44 days, following which non-physical contact (NPC) with a vasectomised male and then physical contact (PC) with the same vasectomised male, occurred, in each of the subsequent 44-day treatments. Non-invasive monitoring of ovarian cyclicity confirmed that mean urinary progesterone concentration was higher during PC than during either NPC or C, despite the fact that the males were vasectomised and incapable of fertilising the females. Examination of penile morphology revealed that males possess epidermal projections on the glans penis which probably bring about cervical stimulation during coitus. These findings together with the female progesterone profiles imply the species is an induced ovulator stimulated by penile intromission.Item Pediatric tuberculosis detection using trained African giant pouched rats(2018 International Pediatric Research Foundation, Inc.) Mgode, G. F.; Cox, C. L.; Mwimanzi, S.; Mulder, C.Item Pediatric tuberculosis detection using trained African giant pouched rats(2018 International Pediatric Research Foundation, Inc., 2018) Mgode, G. F.; Cox, C. L.; Mwimanzi, S.; Mulder, C.BACKGROUND: Tuberculosis (TB) diagnosis in children is a challenge with up to 94% of children with TB treated empirically in TB high-burden countries. Therefore, new diagnostic tests are needed for TB diagnosis. We determined the performance of trained rats in the diagnosis of pediatric TB and whether they can improve detection rate compared to the standard of care. METHODS: Presumptive TB patients in 24 TB clinics in Tanzania were tested. Samples indicated as TB-positive by rats underwent confirmation by concentrated smear microscopy. TB yield of bacteriologically confirmed pediatric TB patients (≤5 years) was compared with yield of standard of care. RESULTS: Sputum samples from 55,148 presumptive TB patients were tested. Nine hundred eighty-two (1.8%) were the children between 1 and 5 years. Clinics detected 34 bacteriologically positive children, whereas rats detected additional 23 children yielding 57 bacteriologically TB- positive children. Rats increased pediatric TB detection by 67.6%. Among 1–14-year-old children, clinics detected 331 bacteriologically positive TB whereas rats found the additional 208 children with TB that were missed by clinics. Relative increase in TB case detection by rats decreased with the increase in age (Po0.0001). CONCLUSION: Trained rats increase pediatric TB detection significantly and could help address the pediatric TB diagnosis challenges. Further determination of accuracy of rats involving other sample types is still needed.Item Relic populations of Fukomys mole- rats in Tanzania: description of two new species F. livingstoni sp. nov. and F. hanangensis sp. nov.(Faulkes / PeerJ) Faulkes, C. G.; Mgode, G. F.; Archer, E. K.; Bennett, N. C.Item Rodents and Shrews as Vectors of Zoonotic Spirochetes and Trypanosomes in Tanzania(African Journals Online (AJOL)) Katakweba, A. A. S.; Kipanyula, M. J.; Hamphi; Durnez, L.; Mhamphi, G.; Luziga, C.; Mgode, G. F.; Machang'u, R. S.