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Patrick B. Hamilton - One of the best experts on this subject based on the ideXlab platform.
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New insights from Gorongosa National Park and Niassa National Reserve of Mozambique increasing the genetic diversity of Trypanosoma Vivax and Trypanosoma Vivax-like in tsetse flies, wild ungulates and livestock from East Africa
Parasites & vectors, 2017Co-Authors: Carla M. F. Rodrigues, Herakles A. Garcia, Adriana C. Rodrigues, André G. Costa-martins, Carlos Lopes Pereira, Dagmar L. Pereira, Zakaria Bengaly, Luis Neves, Erney P. Camargo, Patrick B. HamiltonAbstract:Additional file 1: Table S1. Trypanosoma Vivax isolates from Africa, including the host species, geographical origin and groups/genotypes defined by gGAPDH and ITS rDNA analyses. TvL-G: TvL-Gorongosa.
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Is Trypanosoma Vivax genetically diverse
Trends in parasitology, 2012Co-Authors: Patrick B. HamiltonAbstract:In their recent review on diversity of African tsetse fly-transmitted trypanosomes, Tait et al. [1xTrypanosome genetics: populations, phenotypes and diversity. Tait, A. et al. Vet. Parasitol. 2011; 181: 61–68Crossref | PubMed | Scopus (10)See all References[1] suggest that genetic diversity of Trypanosoma Vivax, a major pathogen of African and South American cattle, is limited. This is primarily based on DNA microsatellite analysis of 31 T. Vivax isolates from a single area in The Gambia [2xTrypanosoma Vivax displays a clonal population structure. Duffy, C.W. et al. Int. J. Parasitol. 2009; 39: 1475–1483Crossref | PubMed | Scopus (24)See all References[2]. However, this assessment ignores evidence from several studies that have used isoenzymes [3xA comparison of the isoenzymes of Trypanosoma (Duttonella) Vivax isolates from East Africa and West Africa. Fasogbon, A.I. et al. Int. J. Parasitol. 1990; 20: 389–394Crossref | PubMed | Scopus (25)See all References[3], DNA microsatellites [4xNew molecular marker for Trypanosoma (Duttonella) Vivax identification. Morlais, I. et al. Acta Trop. 2001; 80: 207–213Crossref | PubMed | Scopus (25)See all References, 5xIdentification of Trypanosoma Vivax subtypes isolated from cattle and goats using microsatellite markers. Biryomumaisho, S. et al. Vet. Arhiv. 2011; 81: 13–24See all References] and more recently sequence data [6xThe use of specific and generic primers to identify trypanosome infections of wild tsetse flies in Tanzania by PCR. Malele, I. et al. Infect. Genet. Evol. 2003; 3: 271–279Crossref | PubMed | Scopus (37)See all References, 7xPhylogenetic analysis of Trypanosoma Vivax supports the separation of South American/West African from East African isolates and a new T. Vivax like genotype infecting a nyala antelope from Mozambique. Rodrigues, A.C. et al. Parasitology. 2008; 135: 1317–1328Crossref | PubMed | Scopus (16)See all References, 8xNew Trypanosoma (Duttonella) Vivax genotypes from tsetse flies in East Africa. Adams, E.R. et al. Parasitology. 2010; 137: 641–650Crossref | PubMed | Scopus (20)See all References, 9xThe taxonomic and phylogenetic relationships of Trypanosoma Vivax from South America and Africa. Cortez, A.P. et al. Parasitology. 2006; 133: 159–169Crossref | PubMed | Scopus (45)See all References] that have revealed high levels of genetic diversity within this species, particularly in East Africa. A partial T. Vivax 18S rDNA sequence, obtained from an infected tsetse fly in Tanzania had greatest similarity to that of a West African T. Vivax isolate, yet diverged by 14% [6xThe use of specific and generic primers to identify trypanosome infections of wild tsetse flies in Tanzania by PCR. Malele, I. et al. Infect. Genet. Evol. 2003; 3: 271–279Crossref | PubMed | Scopus (37)See all References[6]; two novel genotypes were discovered in wild antelope from Mozambique, one of which caused severe disease in a goat [7xPhylogenetic analysis of Trypanosoma Vivax supports the separation of South American/West African from East African isolates and a new T. Vivax like genotype infecting a nyala antelope from Mozambique. Rodrigues, A.C. et al. Parasitology. 2008; 135: 1317–1328Crossref | PubMed | Scopus (16)See all References[7], and three diverse genotypes were discovered in tsetse flies from Tanzania [8xNew Trypanosoma (Duttonella) Vivax genotypes from tsetse flies in East Africa. Adams, E.R. et al. Parasitology. 2010; 137: 641–650Crossref | PubMed | Scopus (20)See all References[8]. Indeed, analysis of glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) gene sequences suggests that T. Vivax diversity is similar to that of Trypanosoma congolense [8xNew Trypanosoma (Duttonella) Vivax genotypes from tsetse flies in East Africa. Adams, E.R. et al. Parasitology. 2010; 137: 641–650Crossref | PubMed | Scopus (20)See all References[8], a species where the different strains (forest, savannah and kilifi) arguably represent different species.The limited genetic diversity found in The Gambia [2xTrypanosoma Vivax displays a clonal population structure. Duffy, C.W. et al. Int. J. Parasitol. 2009; 39: 1475–1483Crossref | PubMed | Scopus (24)See all References[2] reflects the results of a study which found isolates with identical gGAPDH gene sequences from across West Africa (The Gambia, Nigeria and Cameroon) and South America [8xNew Trypanosoma (Duttonella) Vivax genotypes from tsetse flies in East Africa. Adams, E.R. et al. Parasitology. 2010; 137: 641–650Crossref | PubMed | Scopus (20)See all References[8]. By contrast, considerable polymorphism (11 distinct alleles) was identified in 31 T. Vivax infections in field-collected tsetse flies from Cameroon, using primers targeting a region that contains a microsatellite sequence [4xNew molecular marker for Trypanosoma (Duttonella) Vivax identification. Morlais, I. et al. Acta Trop. 2001; 80: 207–213Crossref | PubMed | Scopus (25)See all References[4]. The results from these studies are not directly comparable, as they used different genotyping techniques; DNA microsatellites evolve quickly, whereas the gGAPDH gene has a slow evolutionary rate and is generally used for resolving species-level relationships (e.g. [10xPatterns of co-evolution between trypanosomes and their hosts deduced from ribosomal RNA and protein-coding gene phylogenies. Hamilton, P.B. et al. Mol. Phylogenet. Evol. 2007; 43: 15–25Crossref | Scopus (93)See all References[10]). It is therefore difficult to assess the true genetic diversity of T. Vivax in West Africa, particularly as T. Vivax has not been extensively sampled from wild mammals, tsetse flies and other biting flies in the region, which could potentially harbor greater diversity. Additionally, the primer sets used for initial identification [11xSensitive detection of trypanosomes in tsetse-flies by DNA amplification. Masiga, D.K. et al. Int. J. Parasitol. 1992; 22: 909–918Crossref | PubMed | Scopus (203)See all References[11] in the study of Duffy et al. [2xTrypanosoma Vivax displays a clonal population structure. Duffy, C.W. et al. Int. J. Parasitol. 2009; 39: 1475–1483Crossref | PubMed | Scopus (24)See all References[2] lack the ability to detect divergent T. Vivax genotypes [4xNew molecular marker for Trypanosoma (Duttonella) Vivax identification. Morlais, I. et al. Acta Trop. 2001; 80: 207–213Crossref | PubMed | Scopus (25)See all References[4], and this may also be the case for the primer sets used for microsatellite genotyping that were designed from genomic sequences from a West African strain [2xTrypanosoma Vivax displays a clonal population structure. Duffy, C.W. et al. Int. J. Parasitol. 2009; 39: 1475–1483Crossref | PubMed | Scopus (24)See all References[2]. By contrast, the studies that have revealed the diverse genotypes in East Africa have used ‘generic’ primers, designed to amplify DNA from a wide range of trypanosome species, and therefore may be more likely to pick up novel genotypes [7xPhylogenetic analysis of Trypanosoma Vivax supports the separation of South American/West African from East African isolates and a new T. Vivax like genotype infecting a nyala antelope from Mozambique. Rodrigues, A.C. et al. Parasitology. 2008; 135: 1317–1328Crossref | PubMed | Scopus (16)See all References, 9xThe taxonomic and phylogenetic relationships of Trypanosoma Vivax from South America and Africa. Cortez, A.P. et al. Parasitology. 2006; 133: 159–169Crossref | PubMed | Scopus (45)See all References, 12xA novel, high throughput technique for species identification reveals a new species of tsetse-transmitted trypanosome related to the Trypanosoma brucei subgenus, Trypanozoon. Hamilton, P.B. et al. Infect. Genet. Evol. 2008; 8: 26–33Crossref | PubMed | Scopus (33)See all References, 13xTrypanosomes are monophyletic: evidence from genes for glyceraldehyde phosphate dehydrogenase and small subunit ribosomal RNA. Hamilton, P.B. et al. Int. J. Parasitol. 2004; 34: 1393–1404Crossref | PubMed | Scopus (110)See all References].It is clear that our knowledge of the diversity of T. Vivax is limited. Understanding the true diversity of this important parasite and its significance in terms of diagnosis, disease, differential drug response and the evolution of resistance to chemotherapeutic treatments will require broader surveys and improved genotyping techniques.
K.a.n. Esievo - One of the best experts on this subject based on the ideXlab platform.
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The effect of experimental The effect of experimental Trypanosoma Vivax Trypanosoma Vivax infection on the
2009Co-Authors: M. Y. Fatihu, S. Adamu, Lawrence Oghenemin, Oghenemin Eduvie, Akpofure, Nelson Esievo, N. D. G. Ibrahim, L.o. Eduvie, K.a.n. EsievoAbstract:Thyroid gland dysfunction was studied in Zebu cattle experimentally infected with Thyroid gland dysfunction was studied in Zebu cattle experimentally infected with Trypanosoma Vivax, Trypanosoma Vivax, based on the levels of serum thyroxine (T based on the levels of serum thyroxine (T 4 ) and occurrence of pathological lesions at 13 weeks post infection ) and occurrence of pathological lesions at 13 weeks post infection (p.i.). There were statistically signifi cant declines in the T (p.i.). There were statistically signifi cant declines in the T4 levels in the infected group at 3 weeks p.i. (P 0.05) and control bulls showed no gross lesions and the mean weights were not statistically signifi cant (P>0.05) between the groups. Histopathological lesions observed in the thyroid glands of the infected bulls were between the groups. Histopathological lesions observed in the thyroid glands of the infected bulls were focal in occurrence and include; squamous metaplasia of follicular epithelium with fi broplasia and widened focal in occurrence and include; squamous metaplasia of follicular epithelium with fi broplasia and widened interfollicular connective tissue. The control bulls showed no histopathological lesions in the thyroid glands. interfollicular connective tissue. The control bulls showed no histopathological lesions in the thyroid glands. It was concluded that thyroid gland dysfunction occurs in trypanosomosis due to It was concluded that thyroid gland dysfunction occurs in trypanosomosis due to T. Vivax T. Vivax in cattle and it is in cattle and it is suggested that this could contribute to the weakness associated with trypanosomosis. suggested that this could contribute to the weakness associated with trypanosomosis.
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characterization of sialidase from bloodstream forms of Trypanosoma Vivax
Cell Biochemistry and Function, 2006Co-Authors: L B Buratai, A. J. Nok, I. A. Umar, Sani Ibrahim, K.a.n. EsievoAbstract:Sialidase (EC: 3.2.1.18) from Trypanosoma Vivax (Agari Strain) was isolated from bloodstream forms of the parasite and purified to apparent electrophoretic homogeneity. The enzyme was purified 77-fold with a yield of 32% and co-eluted as a 66-kDa protein from a Sephadex G 110 column. The T. Vivax sialidase was optimally active at 37°C with an activation energy (Ea) of 26.2 kJ mole−1. The pH activity profile was broad with optimal activity at 6.5. The enzyme was activated by dithiothreitol and strongly inhibited by para-hydroxy mercuricbenzoate thus implicating a sulfhydryl group as a possible active site residue of the enzyme. Theenzyme hydrolysed Neu5Ac2,3lac and fetuin. It was inactive towards Neu5Ac2,6lac, colomic acid and the gangliosides GM1, and GDI. Initial velocity studies, for the determination of kinetic constants with fetuin as substrate gave a Vmax of 142.86 μmol h−1 mg−1 and a KM of 0.45 mM. The KM and Vmax with Neu5Ac-2,3lac were 0.17 mM and 840 μmole h−1 mg−1 respectively. The T. Vivax sialidase was inhibited competitively by both 2,3 dideoxy neuraminic acid (Neu5Ac2,3en) and para-hydroxy oxamic acid. When ghost RBCs were used as substrates, the enzyme desialylated the RBCs from camel, goat, and zebu bull. The RBCs from dog, mouse and ndama bull were resistant to hydrolysis. Copyright © 2005 John Wiley & Sons, Ltd.
I. A. Umar - One of the best experts on this subject based on the ideXlab platform.
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characterization of sialidase from bloodstream forms of Trypanosoma Vivax
Cell Biochemistry and Function, 2006Co-Authors: L B Buratai, A. J. Nok, I. A. Umar, Sani Ibrahim, K.a.n. EsievoAbstract:Sialidase (EC: 3.2.1.18) from Trypanosoma Vivax (Agari Strain) was isolated from bloodstream forms of the parasite and purified to apparent electrophoretic homogeneity. The enzyme was purified 77-fold with a yield of 32% and co-eluted as a 66-kDa protein from a Sephadex G 110 column. The T. Vivax sialidase was optimally active at 37°C with an activation energy (Ea) of 26.2 kJ mole−1. The pH activity profile was broad with optimal activity at 6.5. The enzyme was activated by dithiothreitol and strongly inhibited by para-hydroxy mercuricbenzoate thus implicating a sulfhydryl group as a possible active site residue of the enzyme. Theenzyme hydrolysed Neu5Ac2,3lac and fetuin. It was inactive towards Neu5Ac2,6lac, colomic acid and the gangliosides GM1, and GDI. Initial velocity studies, for the determination of kinetic constants with fetuin as substrate gave a Vmax of 142.86 μmol h−1 mg−1 and a KM of 0.45 mM. The KM and Vmax with Neu5Ac-2,3lac were 0.17 mM and 840 μmole h−1 mg−1 respectively. The T. Vivax sialidase was inhibited competitively by both 2,3 dideoxy neuraminic acid (Neu5Ac2,3en) and para-hydroxy oxamic acid. When ghost RBCs were used as substrates, the enzyme desialylated the RBCs from camel, goat, and zebu bull. The RBCs from dog, mouse and ndama bull were resistant to hydrolysis. Copyright © 2005 John Wiley & Sons, Ltd.
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Effects of acute bovine trypanosomosis (Trypanosoma Vivax) on plasma kinetics of intravenously administered lactose
Veterinary Parasitology, 1998Co-Authors: I. A. Umar, J. J. Omage, A. Shugaba, I.o. Igbokwe, Najume Dogon-giginya Ibrahim, Kwem B. Kadima, D. A. Ameh, Helen O. Kwanashie, R.i.s. Agbede, D.i. SarorAbstract:Abstract Four calves infected with Trypanosoma Vivax and four uninfected control calves were each injected intravenously with repeated doses of 0.5 g lactose kg−1 body weight, thrice daily at intervals of 4 h. Plasma samples were collected at specified time intervals and analysed for lactose. Pharmacokinetic parameters were calculated from the data. T. Vivax infection delayed excretion of lactose from the body, thus leading to significantly (P
L B Buratai - One of the best experts on this subject based on the ideXlab platform.
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characterization of sialidase from bloodstream forms of Trypanosoma Vivax
Cell Biochemistry and Function, 2006Co-Authors: L B Buratai, A. J. Nok, I. A. Umar, Sani Ibrahim, K.a.n. EsievoAbstract:Sialidase (EC: 3.2.1.18) from Trypanosoma Vivax (Agari Strain) was isolated from bloodstream forms of the parasite and purified to apparent electrophoretic homogeneity. The enzyme was purified 77-fold with a yield of 32% and co-eluted as a 66-kDa protein from a Sephadex G 110 column. The T. Vivax sialidase was optimally active at 37°C with an activation energy (Ea) of 26.2 kJ mole−1. The pH activity profile was broad with optimal activity at 6.5. The enzyme was activated by dithiothreitol and strongly inhibited by para-hydroxy mercuricbenzoate thus implicating a sulfhydryl group as a possible active site residue of the enzyme. Theenzyme hydrolysed Neu5Ac2,3lac and fetuin. It was inactive towards Neu5Ac2,6lac, colomic acid and the gangliosides GM1, and GDI. Initial velocity studies, for the determination of kinetic constants with fetuin as substrate gave a Vmax of 142.86 μmol h−1 mg−1 and a KM of 0.45 mM. The KM and Vmax with Neu5Ac-2,3lac were 0.17 mM and 840 μmole h−1 mg−1 respectively. The T. Vivax sialidase was inhibited competitively by both 2,3 dideoxy neuraminic acid (Neu5Ac2,3en) and para-hydroxy oxamic acid. When ghost RBCs were used as substrates, the enzyme desialylated the RBCs from camel, goat, and zebu bull. The RBCs from dog, mouse and ndama bull were resistant to hydrolysis. Copyright © 2005 John Wiley & Sons, Ltd.
Alberto M. R. Dávila - One of the best experts on this subject based on the ideXlab platform.
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Trypanosoma Vivax out of africa
Trends in Parasitology, 2001Co-Authors: Tudor W. Jones, Alberto M. R. DávilaAbstract:Trypanosoma Vivax is a blood parasite of ruminants that was introduced into Latin America in cattle imported from Africa, possibly in the late 19th century. The parasite has now spread to ten of the 13 countries of the South American continent, often resulting in a severe wasting disease and death. Here, we review the current state of knowledge about this parasite and the problems faced by animal health agencies in controlling the disease.
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Trypanosoma Vivax – out of Africa
Trends in parasitology, 2001Co-Authors: Tudor W. Jones, Alberto M. R. DávilaAbstract:Trypanosoma Vivax is a blood parasite of ruminants that was introduced into Latin America in cattle imported from Africa, possibly in the late 19th century. The parasite has now spread to ten of the 13 countries of the South American continent, often resulting in a severe wasting disease and death. Here, we review the current state of knowledge about this parasite and the problems faced by animal health agencies in controlling the disease.
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Bovine trypanosomosis due to Trypanosoma Vivax in the German Bush province, Bolivia
Parasitología al día, 2001Co-Authors: R A M S Silva, Alberto M. R. DávilaAbstract:Trypanosoma Vivax es un hemoparasito encontrado en la region de la mosca tse-tse en Africa. Sin embargo, el se ha difundido a otras partes de Africa, Centro-America, Sud-America, Indias Occidentales e Islas Mauricio. Este trabajo es un relato de la primera occurencia de T. Vivax en la provincia de German Bush, Bolivia. T. Vivax fue identificado en 45% de los 80 bovinos examinados por el test de microhematocrito. Los sintomas clinicos observados fueran fiebre, anemia, abortos, emagrecimiento progresivo, perdida substancial de peso en tiempo corto y emaciacion progresiva y linfonodos aumentados. Lo resultados de este estudio sugieren que la difusion acelerada de T. Vivax podrian representar un serio impacto a la economia de la region
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Estimated Financial Impact of Trypanosoma Vivax on the Brazilian Pantanal and Bolivian Lowlands
Memorias do Instituto Oswaldo Cruz, 1999Co-Authors: Andrew Seidl, Alberto M. R. Dávila, R A M S SilvaAbstract:The financial impact of the first outbreak of Trypanosoma Vivax in the Brazilian Pantanal wetland is estimated. Results are extended to include outbreaks in the Bolivian lowlands providing a notion of the potential influence of the disease and an analytical basis. More than 11 million head of cattle, valued at more than US$3 billion are found in the Brazilian Pantanal and Bolivian lowlands. The total estimated cost of the 1995 outbreak of T. Vivax is the sum of the present values of mortality, abortion, and productivity losses and treatment costs, or about 4% of total brood cow value on affected ranches. Had the outbreak gone untreated, the estimated losses would have exceeded 17% of total brood cow value.
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Marker Discovery In Trypanosoma Vivax Through GSS and Comparative Analysis
Applications of Gene-Based Technologies for Improving Animal Production and Health in Developing Countries, 1Co-Authors: Alberto M. R. Dávila, Luana Tatiana Albuquerque Guerreiro, Silvana S. SouzaAbstract:Trypanosoma Vivax is a haemoparasite affecting the livestock industry in South America and Africa. Despite the high economic relevance of the disease caused by T. Vivax, little work has been done on its molecular characterization, in contrast with human trypanosomes, such as T. brucei and T. cruzi. The present study reports the construction of a semi-normalized genomic library and the sequencing of 160 Genome Sequence Survey (GSS) ends of T. Vivax. The analyses of this preliminary data show that this simple and rapid approach worked well to generate some potential new markers for this species.
