Detecção de anticorpos contra o vírus da diarréia viral bovina no soro sangüíneo, no leite individual e no leite de conjunto em tanque de expansão de rebanhos não vacinados

Pela pesquisa de anticorpos contra o vírus da diarréia viral bovina (BVD), utilizando o teste de ELISA indireto, foi estudada a correlação existente entre a proporção de vacas lactantes e a presença de anticorpos no leite de conjunto do tanque de expansão. Para isso foram analisadas amostras de soro sangüíneo e de leite individual de 376 vacas lactantes não vacinadas, provenientes de 10 propriedades localizadas nas regiões Sul do Estado de Minas Gerais e Nordeste do Estado de São Paulo, assim como uma amostra do leite do tanque de expansão de cada rebanho. em todas as propriedades foram encontradas vacas reagentes no soro sangüíneo, cuja freqüência variou de 12,28 a 100,00%. Já a análise do leite individual não revelou animais reagentes em duas propriedades, e nas demais a freqüência variou de 5,26 a 70,83%. Foram detectados anticorpos no leite do tanque de expansão das propriedades cuja proporção de soros sangüíneos reagentes foi igual a ou maior que 82,86%, e cuja proporção de leites individuais reagentes foi igual a ou maior que 32,14%.

Ocorrência da diarréia viral bovina nas regiões sul do Estado de Minas Gerais e nordeste do Estado de São Paulo

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

Experimental infection of Newcastle disease virus in pigeons (Columba livia): Humoral antibody response, contact transmission and viral genome shedding

The aim of this study was to evaluate the humoral antibody response, the genome viral excretion and the contact transmission of pathogenic chicken origin Newcastle disease virus (NDV) from experimentally infected pigeons (Columba livia) to in-contact pigeon. The antibody response to infection was assessed by the hemagglutination inhibition (HI) test and the genome viral excretion was detected by RT-PCR. Viral strain induced high antibody levels, both in inoculated and in sentinel birds. The pathogenic viral strain for chickens was unable to produce clinical signs of the disease in experimentally infected pigeons, although it induced the Immoral antibody response and produced NDV genome shedding. NDV genome was detected intermittently throughout the experimental period, from 5 days post-infection (dpi) to 24 dpi. Therefore, viral genome shedding occurred for 20 days. The viral genome was detected in all birds, between I I and 13 dpi. Furthermore, the high infectivity of the virus was confirmed, as all non-inoculated sentinel pigeons showed antibody levels as high as those of inoculated birds. (C) 2007 Elsevier B.V. All rights reserved.

Control of Salmonella enterica serovar Enteritidis in laying hens by inactivated Salmonella Enteritidis vaccines

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

Algoritmo memético com infecção viral: uma aplicação ao problema do caixeiro viajante assimétrico

The Combinatorial Optimization is a basic area to companies who look for competitive advantages in the diverse productive sectors and the Assimetric Travelling Salesman Problem, which one classifies as one of the most important problems of this area, for being a problem of the NP-hard class and for possessing diverse practical applications, has increased interest of researchers in the development of metaheuristics each more efficient to assist in its resolution, as it is the case of Memetic Algorithms, which is a evolutionary algorithms that it is used of the genetic operation in combination with a local search procedure. This work explores the technique of Viral Infection in one Memetic Algorithms where the infection substitutes the mutation operator for obtaining a fast evolution or extinguishing of species (KANOH et al, 1996) providing a form of acceleration and improvement of the solution . For this it developed four variants of Viral Infection applied in the Memetic Algorithms for resolution of the Assimetric Travelling Salesman Problem where the agent and the virus pass for a symbiosis process which favored the attainment of a hybrid evolutionary algorithms and computational viable

Molecular mapping of the viral determinants of systemic wilting induced by a Lettuce mosaic virus (LMV) isolate in some lettuce cultivars

The isolate AF199 of Lettuce mosaic virus (LMV, genus Potyvirus) causes local lesions followed by systemic wilting and plant death in the lettuce cultivars Ithaca and Vanguard 75. Analysis of the phenotype of virus chimeras revealed that a region within the PI protein coding region (nucleotides 112-386 in the viral genome) and/or another one within the CI protein coding region (nucleoticles 5496-5855) are sufficient together to cause the lethal wilting in Ithaca, but not in Vanguard 75. This indicates that the determinants of this particular symptom are different in these two lettuce cultivars. The wilting phenotype was not directly correlated with differences in the deduced amino acid sequence of these two regions. Furthermore, transient expression of the LMV-AF 199 proteins, separately or in combination, did not induce local necrosis or any other visible reaction in the plants. Together, these results Suggest that the systemic wilting reaction might be Clue to RNA rather than protein sequences. (c) 2004 Elsevier B.V. All rights reserved.

Estratégias de Produção in vitro de Bioinseticida Viral: influências do Isolado, da Cinética e do Modo de operação

Societal concerns about environmental sustainability has lead to the development of ecologically-friendly alternatives to chemical insecticides for crop protection. One such alternative is biological pest control. In particular, baculoviruses are well suited as insect biopesticides due to their narrow host specificity and relative ease of propagation. In Brazil, the baculovirus Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) is the main biological control agent employed for the soybean pest, Anticarsia gemmatalis. This baculovirus biopesticide is currently produced using caterpillars, but increasing market demand for the product has encouraged the development of an in vitro manufacturing process, which can be scaled up to much higher virus productivities. In this study, three wild-type AgMNPV isolates (AgMNPV-2D, AgMNPV-MP2 and AgMNPV-MP5) and a recombinant form (vAgEGT-LacZ) were characterised in terms of occlusion body (OB) production and infection kinetics, to enable future optimisation of the in vitro production process. These viruses were propagated using a Spodoptera frugiperda (IPLB-SF21) insect cell line grown in shaker-flask batch cultures. Among the virus isolates tested, AgMNPV-MP5 was found to be the best producer, yielding (5.3±0.85)x108 OB/mL after 8 days post infection. The characterisation of vAgEGT-LacZ propagation in suspension cell cultures has not been previously reported in the literature; hence it became the main focus for this thesis. In particular, it was carried out a study on the effect of the multiplicity of infection (MOI) on OB production. Five successive batches were performed getting a final production (8.9±1.42)x1014 occlusion bodies, considering that production is related for a bioreactor with final volume of 10m3. A low MOI associated with a fed-batch process for vAgEGT-LacZ production was found to support a 3-fold higher OB yield when compared to the default batch process (1.8x107 and 5.3x107 OB/mL, respectively). This yield is competitive with regards to the production process.

DNA viruses in human cancer: An integrated overview on fundamental mechanisms of viral carcinogenesis

The first experimental data suggesting that neoplasm development in animals might be influenced by infectious agents were published in the early 1900s. However, conclusive evidence that DNA viruses play a role in the pathogenesis of some human cancers only emerged in the 1950s, when Epstein-Barr virus (EBV) was discovered within Burkitt lymphoma cells. Besides EBV, other DNA viruses consistently associated with human cancers are the hepatitis B virus (HBV), human papillomavirus (HPV), and Kaposi sarcoma herpesvirus (KSHV). Although each virus has unique features, it is becoming clearer that all these oncogenic agents target multiple cellular pathways to support malignant transformation and tumor development. (c) 2006 Elsevier B.V.. All rights reserved.

HIV, EBV and KSHV: Viral cooperation in the pathogenesis of human malignancies

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

Soroprevalência da arterite viral equina em mesorregiões paulistas entre 2007 e 2008

This study investigated the occurrence of equine arteritis virus antibodies using neutralization test in 1,400 horses from Campinas and macro metropolitan paulista mesoregions located at São Paulo State, between 2007 and 2008. Eighty (5.7%) samples showed antibodies to virus (titers from 4 to 4,096). Among the 42 cities, 15 (35.7%) presented at least one seropositive animal to equine arteritis virus. of the 238 farms analyzed 41 showed at least one seropositive animal. The occurrence was higher in sport horses like jumping horses, Quarter horses and was similar for female and male. The rate of seropositive was higher in animals older than 24 months of age. These results suggest the virus circulation among horse population in studied farms, and the need for continuing epidemiological surveillance studies.

Papilomatose oral em cães: revisão da literatura e estudo de doze casos

Canine papillomatosis is an infectious viral disease characterized by oral, cutaneous or ocular papillomas, usually benign. The treatment is indicated in animals, with multiple tumors that produce pharyngeal obstruction, and problems, of eating or for aesthetic reasons. Different treatment protocols have been proposed, including surgical excision, cryosurgery, electro surgery, autogenous or recombinant vaccines, imunomodulators drugs, systemic and intralesional chemotherapy. In this study were reviewed the more important aspects of canine oral papillomatosis. In the 12 studied animals, the papillomas were observed predominantly in mouth, gum and palate regions, in puppies until 12 months, presenting combined infection with ehrlichiosis. The treatment using Propionibacterium acnes and/or autogenous vaccine showed efficacy in eight dogs (66.7%).

Influence of Viral Infection on Essential Oil Composition of Ocimum basilicum (Lamiaceae)

Ocimum basilicum L., popularly known as sweet basil, is a Lamiaceae species whose essential oil is mainly composed of monoterpenes, sesquiterpenes and phenylpropanoids. The contents of these compounds can be affected by abiotic and biotic factors such as infections caused by viruses. The main goal of this research was an investigation of the effects of viral infection on the essential oil profile of common basil. Seeds of O. basilicum L. cv. Genovese were sowed and kept in a greenhouse. Plants presenting two pairs of leaves above the cotyledons were inoculated with an unidentified virus isolated from a field plant showing chlorotic yellow spots and foliar deformation. Essential oils of healthy and infected plants were extracted by hydrodistillation and analyzed by GCMS. Changes in essential oil composition due to viral infection were observed. Methyleugenol and p-cresol,2,6-di-tert-butyl were the main constituents. However, methyleugenol contents were significantly decreased in infected plants.

Vírus da leucemia felina: análise da classificação da infecção, das técnicas de diagnóstico e da eficácia da vacinação com o emprego de técnicas sensíveis de detecção viral

O Vírus da leucemia felina (FeLV) pertence à família Retroviridae, gênero Gammaretrovirus. Diferentemente de outras retroviroses, uma parcela dos gatos jovens e adultos exposta ao FeLV não apresenta antigenemia/viremia, de acordo com as técnicas convencionais de detecção viral, como isolamento em cultivo celular, imunofluorescência direta e ELISA. O emprego de técnicas de maior sensibilidade para detecção e quantificação viral, como o PCR quantitativo, permitiu a identificação de animais positivos para a presença de DNA proviral e RNA na ausência de antigenemia/viremia e, com isso, um refinamento da análise das diferentes evoluções da infecção. Assim, reclassificou-se a patogenia do FeLV em 4 categorias: infecção abortiva, regressiva, latente e progressiva. Foi possível também detectar DNA proviral e RNA em animais considerados imunes ao FeLV após vacinação. Diante disso, os objetivos desta revisão de literatura foram demonstrar as implicações da utilização de técnicas sensíveis de detecção viral na interpretação e classificação da infecção do FeLV e rever as técnicas de detecção do vírus para fins de diagnóstico. Além disso, apresentar os resultados referentes à eficácia da vacinação contra o FeLV com a utilização dessas técnicas.

Modulatory effects of tuberculosis vaccines on experimental autoimmune encephalomyelitis

Although BCG is the only accepted vaccine against tuberculosis (TB), its protective ability is very limited. Therefore, many new vaccines are being evaluated. Our group has been working on DNAhsp65 - a genetic construction containing the hsp65 gene from Mycobacterium leprae. In previous experimental works, we demonstrated that both DNAhsp65 alone or associated with BCG, in a prime-boost regimen, were effective to control TB. A possible deleterious effect related to autoimmunity needed to be tested because hsp65 is highly homologous to the correspondent mammalian protein. In this investigation we tested the effect of a previous immunization with DNAhsp65 alone or associated with BCG in a rat model of multiple sclerosis. Female Lewis rats were immunized with three doses of DNAhsp65 or primed with BCG followed by two DNAhsp65 boosters. The animals were, then, immunized with myelin associated with complete Freund's adjuvant to develop experimental autoimmune encephalomyelitis (EAE). The following parameters were evaluated: weight loss, clinical score, central nervous system (CNS) inflammation and anti-myelin immune response. No deleterious effect was associated with these immunizations schedules. Immunized animals equally lost weight, the clinical scores were similar and CNS inflammation did not increase. Interestingly, both procedures determined decreased inflammation in the brain and lumbar spinal cord. This was concurrent with a modulatory effect over cytokine production by peripheral lymphoid organs. Cell cultures from spleen and lymph nodes in vitro stimulated with myelin produced less IFN-gamma and IL-10, respectively. This phenomenon was more clear in rats immunized with the genetic vaccine alone than with the prime-boost strategy. Together the results suggest that these strategies for TB prophylaxis would not accelerate or aggravate multiple sclerosis, being therefore, safe in this aspect. In addition, they indicate that these vaccination regimens have a potential anti-inflammatory activity that could be better explored in the future.