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Rodriguez-Roche R.,Institute of Tropical Medicine | Villegas E.,Instituto Experimental Jose Witremundo Torrealba | Cook S.,Natural History Museum in London | Poh Kim P.A.W.,Genome Institute of Singapore | And 6 more authors.
Infection, Genetics and Evolution | Year: 2012

During the past three decades there has been a notable increase in dengue disease severity in Venezuela. Nevertheless, the population structure of the viruses being transmitted in this country is not well understood. Here, we present a molecular epidemiological study on dengue viruses (DENV) circulating in Aragua State, Venezuela during 2006-2007. Twenty-one DENV full-length genomes representing all of the four serotypes were amplified and sequenced directly from the serum samples. Notably, only DENV-2 was associated with severe disease. Phylogenetic trees constructed using Bayesian methods indicated that only one genotype was circulating for each serotype. However, extensive viral genetic diversity was found in DENV isolated from the same area during the same period, indicating significant in situ evolution since the introduction of these genotypes. Collectively, the results suggest that the non-structural (NS) proteins may play an important role in DENV evolution, particularly NS1, NS2A and NS4B proteins. The phylogenetic data provide evidence to suggest that multiple introductions of DENV have occurred from the Latin American region into Venezuela and vice versa. The implications of the significant viral genetic diversity generated during hyperendemic transmission, particularly in NS protein are discussed and considered in the context of future development and use of human monoclonal antibodies as antivirals and tetravalent vaccines. © 2011 Elsevier B.V.

Garcia D.E.,University of Los Andes, Venezuela | Cova L.J.,Instituto Experimental Jose Witremundo Torrealba | Scorza D.J.S.,Instituto Experimental Jose Witremundo Torrealba | Gonzalez M.E.,Nucleo Universitario | And 4 more authors.
Revista de la Facultad de Agronomia | Year: 2012

It was evaluated the weight and volume of the heart (C), kidneys (R), liver (H) and intestine (I), and intestine length (LI), in 72 Golden Hamster (Mesocrisetus auratus L.) consuming diets (D) made with red worm (Eisenia spp.; HL) meal and described as: D1: PB=13.5% (HL: 21%); D2: PB=15.4% (HL: 24%); D3: PB=17.6% (HL: 27%); D4: PB=19.6% (HL: 30%) and two commercial feeds (D0: Conejarina®; PB=11.1% and D5: Ratarina®; PB=21.1%). The study was conducted at the vivarium of the Núcleo Universitario «Rafael Rangel, Universidad de los Andes, Trujillo, Venezuela. The data were analyzed by means of the statistical program SPSS v10.0 as a completely randomized design, in which the diets were considered the treatments. No differences in C weight (280-350 mg) were observed among diets. Animals fed with D2, D3 y D5 exhibit greater R weight (445-458 mg). The greater weight of the I was observed in the animals consuming D3 (12.4 g); while those consuming D4 had a similar weight (13,2 g) at day 9 of the experiment, time at which were removed from the study due to intoxication symptoms. No differences in C (0.35-0.40 cm3) and R (0.26-0.45 cm3) volume were observed among diets. The volume of H and I in the hamsters fed with D2 (H:2.17 cm3; I:17.33 cm3; LI:49.27 cm) and D3 (H:2.30 cm3; I:18,67 cm3; LI:50,33 cm) were greater than in the other experimental groups (H:1.50 cm3; I:10.17 cm3; LI:33.15 cm). Animals consuming D2, D3 and D4 affected drastically the morphometry of H and I, whereas they were similar between hamster fed with D1 and Ratarina®. The HL represent a protein supplement of excellent nutritional quality for the Golden Hamster when is included in the diet in a proportion of 21%. Inclusion of greater percentages of HL, as was done in D2, D3 and D4, might produce harmful effects due to high concentrations of biogenic amines in such diets.

Garcia D.E.,University of Los Andes, Venezuela | Cova L.J.,Instituto Experimental Jose Witremundo Torrealba | Briceno S.,Instituto Venezolano del Seguro Social | Scorza D.J.V.,Instituto Experimental Jose Witremundo Torrealba | And 4 more authors.
Archivos de Zootecnia | Year: 2012

Content of total protein (PT), albumin (Alb), globulins (Glb), urea (U), uric acid (AU), creatinine (Ct) and transaminase levels (oxalacetic-glutamic (TGO) and piruvic-glutamic (TGP)) was evaluated in the blood plasm of golden hamster (Mesocrisetus auratus L.), fed diets (crude protein; PB= 13.5- 19.6%) with red worm (HL) (Eisenia spp.) meal and two conventional feeds (Conejarina®; PB= 11.4% and Ratarina®; PB= 21.1%). The PT, Alb, Glb and Ct concentration oscillated among 5-6, 2- 3, 2-3 g/dL y 0,3-0,4 mg/dL, respectively, no significant differences among the treatments in the assay were observed (p>0.05). In the assay the U and AU content fluctuated between 23-101 y 3-9 mg/dL, respectively; according to the PB level, HL inclusion and measurement time. The transaminase levels were high and variables during the second week of assay, according to the proteic level diets (TGO: 101-699 y TGP: 54-890 UI/ L). The seric PT, Glb, Alb and Ct content were independent of PB diets and HL proportion, while the U (R2= 0.509*), TGO (R2= 0.661**) and TGP (R2= 0.524*) level were related with proteic level of diets, and the U (R2= 0.502*) and AU (R2= 0.531*) contents with the HL inclusion. The HL addition in 24, 27 and 30% for making formulated proteic diets to M. auratus cause significant variation in the normal values of U, AU and transaminases.

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