24 resultados para Virus do herpes

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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The objectives were to assess incidence of pregnancy losses, associate this outcome with immunization programs against reproductive diseases, and evaluate the effects of vaccination against bovine herpesvirus-1 (BoHV-1), bovine viral diarrhea virus (BVDV), and Leptospira spp., on reproductive efficiency of Brazilian cow-calf operations. In experiment 1, 7614 lactating Nelore cows from 18 ranches were assigned to the same estrus synchronization and fixed-time AI protocol (ESFTAI; Days -11 to 0). Pregnancy status was determined with transrectal ultrasonography on Days 30 and 120 after AI. Pregnancy loss was deemed to have occurred when cows were pregnant on Day 30 but nonpregnant on Day 120. Incidence of pregnancy loss across all ranches was 4.1%; pregnancy losses were detected (P < 0.10) in 14 ranches but not detected (P > 0.11) in four ranches. Pregnancy loss was lower (P ≤ 0.02) in ranches that vaccinated against BoHV-1, BVDV, and Leptospira spp. compared with ranches that did not vaccinate, or only vaccinated against Leptospira spp. In experiments 2 and 3, lactating Nelore cows (N = 1950 and 2793, respectively) from ranches that did not have a history of vaccinating against reproductive diseases (experiment 2), or only vaccinated against Leptospira spp. (experiment 3), were assigned to the same ESFTAI used in experiment 1. Within each ranch, cows received (VAC) or not (CON) vaccination against BoHV-1, BVDV, and Leptospira spp. at the beginning of the ESFTAI (Day -11) and 30 days after (Day 41) AI. In experiment 2, VAC cows had greater (P ≤ 0.05) pregnancy rates compared with CON on Days 30 and 120. In experiments 2 and 3, pregnancy loss was reduced (P ≤ 0.03) in primiparous VAC cows compared with CON cohorts. In experiment 4, 367 primiparous, lactating Nelore cows previously vaccinated against Leptospira spp. were assigned to the same ESFTAI used in experiment 1. Cows received VAC, or the same vaccine 30 days before (Day -41) and at the beginning (Day -11) of the ESFTAI (PREVAC). Pregnancy rates on Days 30 and 120 were greater (P ≤ 0.05) in PREVAC cows compared with VAC cows. In conclusion, pregnancy losses affected reproductive and overall efficiency of Brazilian cow-calf operations, and might be directly associated with BoHV-1, BVDV, and Leptospira spp. infections. Hence, vaccinating cows against these pathogens, particularly when both doses are administered before fixed-time AI, improved reproductive performance in Brazilian cow-calf systems. © 2013 Elsevier Inc.

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Four experiments evaluated the effects of vaccination against bovine herpesvirus-1 (BoHV-1), bovine viral diarrhea virus (BVDV), and Leptospira spp. on reproductive performance of lactating dairy cows without (experiments 1, 2, and 3) or with previous vaccination against these diseases (experiment 4). Cows were assigned to a fixed-time AI protocol (FTAI; d -11 to 0) in all experiments, as well as AI 12. h upon estrus detection in experiment 3. Pregnancy status was determined with transrectal ultrasonography on d 30 and 71 (d 60 for experiment 3) after AI. Pregnancy loss was considered in cows pregnant on d 30 but non-pregnant on the subsequent evaluation. In experiment 1, 853 cows received (VAC) or not (CON) vaccination against BoHV-1, BVDV, and Leptospira spp. at the beginning of the FTAI (d -11) and 30. d after AI. Pregnancy loss was reduced (P=0.03) in VAC cows compared with CON. In experiment 2, 287 cows received VAC or CON 30. d prior to (d -41) and at the beginning (d -11) of the FTAI. Pregnancy rates on d 30 and 71 were greater (P≤0.03) in VAC cows compared with CON. In experiment 3, 1680 cows with more than 28. d in milk were randomly assigned to receive VAC or CON with doses administered 14. d apart, and inseminated within 15-135. d after the second dose. Pregnancy rates on d 30 and 60 were greater (P≤0.02) in VAC cows compared with CON. In experiment 4, 820 cows received (REVAC) or not (CON) revaccination against BoHV-1, BVDV, and Leptospira spp. at the beginning of the FTAI protocol (d -11). Pregnancy rates and loss were similar (P≥0.54) between treatments. Hence, vaccinating naïve cows against BoHV-1, BVDV, and Leptospira spp. improved reproductive efficiency in dairy production systems, particularly when both doses were administered prior to AI. © 2013 Elsevier B.V.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Pós-graduação em Medicina Veterinária - FMVZ

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Pós-graduação em Medicina Veterinária - FCAV

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Pós-graduação em Microbiologia - IBILCE

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The Kaposi-associated Herpesvirus (KSHV) also known as Human Herpesvirus 8 (HHV-8) is associated with the development of Kaposi’s sarcoma (KS) and others limphoprolipheratives diseases such as Primary Effusion Lymphoma (PEL) and Multicentric Castleman Disease (MCD). Even though the virus is considered lymphotropic, it is able to infect others cell types such as macrophages, dendritic cells, endothelial cells, monocytes and fibroblasts. After infection, KSHV be latent expressing essential viral genes to its maintenance in a infected cell. However, in some circumstances may occur the reactivation of lytic cycle producing new viral particles. K1 protein of KSHV interferes in the cellular signaling inducing proliferation and supporting cellular transformation. K1 is encoded by viral ORF-K1, which shows high variability between different genotypes of KSHV. So far, it is not clear whether different isoforms of K1 have specific immunobiological features. The KSHV latency is maintained under strict control by the immune system supported by an adequate antigen presentation involving Human Leucocyte Antigen (HLA) class I and II. Polymorphisms of HLA class I and II genes confer an enormous variability in molecules that recognize a large amount of antigens, but also can increase the susceptibility to autoimmune diseases. Therefore, the present study aims to genotype HLA class I (A and B) and class II (DR and DQ) from volunteers to identify haplotypes that can provide better response to K1 epitopes of different KSHV genotypes. First of all, 20 volunteers were selected to genotype HLA genes. In our results we observed prevalence of certain HLA class I haplotypes as HLAA1, HLA-A2, HLA-A24, HLA-A26, HLA-B8, HLA-B18 e HLA-B44. After the in silico analysis using BIMAS and SYFPEITHI databases, we observed high scores for epitopes from the B genotype of KSHV, indicating...(Complete abstract click electronic access below)

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Kaposi´s sarcoma associated herpesvirus (KSHV) or human herpesvirus 8 (HHV-8) is a gammaherpesvirus essential for the development of all forms of Kaposi´s sarcoma (KS). The KSHV’s life cycle is basically divided into latent and lytic phases, which have distinct viral gene expression profiles. Some important oncogenic products of KSHV are expressed during the lytic phase, including the viral K1 protein. As an effect of interfer-ence with intracellular signaling, K1 expression increases proliferation and survival of KSHV-infected cells. Due to its high level of genetic variability compared to other re-gions of the viral genome, the K1-encoding ORF (ORF-K1) is commonly evaluated for KSHV genotyping. It remains unclear whether different viral genotypes have particular biological effects that might modify the KSHV oncogenicity. The present study aimed to contribute to the establishment of an experimental in vitro model for evaluation of the K1 protein from common KSHV genotypes. Recombinant expression vectors with the ORF-K1 from KSHV genotypes A, B and C were prepared by genetic cloning. The recombi-nant vectors pKSHVOK1 obtained by cloning were sequenced for structural validation. After that, HEK293 cell line was transfected with the recombinant vectors, and proteins were extracted for expression analysis by Western blot technique, for K1 functional vali-dation. Results showed that ORF-K1 vectors containing KSHV ORF-K1 from the A, B and C genotypes were produced and structurally validated by DNA sequencing. The K1 expression at the protein level was also confirmed by immunoblots using an antibody for FLAG detection, an epitope from the vector that binds to K1. Based on presented re-sults, it´s possible to conclude that the recombinant vectors will be able to be used in future studies of K1 protein biological properties from distinct KSHV genotypes