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Bovine papillomavirus (BPV) can cause damage to the epithelial and mucosal tissue and currently presents 28 known types. Not all BPV types are associated with the development of cancer in cattle. Studies have shown that variants of human papillomavirus types can present different pathogenic profiles. However, despite the similarity, it is not yet known whether variants of BPV types can also present varying degrees of pathogenicity. Thus, the aim of this study was to evaluate the genetic variability of BPV types and variants isolated in Northeastern Brazil. Samples were obtained from animals with papillomatous lesions. BPV DNA was detected by the amplification of the L1 gene and genotyping was performed by sequencing. Mutations were analyzed in a phylogenetic, structural and functional context. In total, 52 positive samples were obtained and 11 different BPV types were identified in the samples. Ten putative new BPV types were also identified. In addition, several non-synonymous mutations were identified and predicted to alter protein stability, having an impact on immune evasion. The study demonstrated a high genetic diversity of BPV in the region with a large number of mutations identified, serving as a basis for more efficient control measures to be adopted for bovine papillomatosis.

Randomly amplified polymorphic DNA (RAPD) has been widely used for epidemiological and phylogenetic purposes ow-ing to its rapidity and efficiency. The aim of this study was to perform genome typing of Salmonella samples isolated from different sources by RAPD profiling. Thirty-three Salmonella samples from the bacterial collection of the Laboratorio de Virologia Comparada, Departamento de Morfologia, Universidade Federal de Sergipe, Brazil, and two standard samples were used. RAPD profiling was conducted using six primers of the Ready-To-Go RAPD system. The amplified products were electro-phoresed on 5% polyacrylamide gel and silver-stained. RAPD analysis resulted in reproducible and stable banding patterns and showed high genetic diversity among the isolated strains. The Primer P1-generated dendrogram showed an epidemiologic relationship between the human and poultry isolated samples, highlighting the usefulness of RAPD for molecular typing and epidemiological studies.

A genetic vaccine consisting of the bovine herpesvirus-1.2a (BHV-1.2a) glycoprotein D (gD) gene under the control of the cytomegalovirus immediate-early promoter/enhancer was generated and administered to sheep intramuscularly in the neck. All animals developed serum antibodies which recognized the homologous antigen (BHV-1.2a strain BH-83) and also exhibited cross-reactivity against the heterologous antigen (BHV-5 strain EVI-190). Three intramuscularly injections were given but serological responses were not improved after the second inoculation. Specific antibodies were detected against BHV-1.2a until at least 12 months after the first inoculation. However, the capacity to induce antibodies against BHV-5 was lower and of shorter duration than to BHV-1.2a. _________________________________________________________________________________________ ABSTRACT: Uma vacina geneticamente preparada com o gene da glicoproteína D do herpesvirus bovino-1.2a (BHV-1.2a) controlado com o promotor/potenciador imediatamente precoce de citomegalovírus foi administrada no pescoço de ovinos. Todos os animais produziram anticorpos séricos que reconheceram, em ELISA, o antígeno homólogo (BHV-1.2a, amostra BH-83) e também mostraram reatividade cruzada contra um antígeno heterólogo (BHV-5 amostra EVI-190). Foram aplicadas três inoculações, mas não houve melhora de resposta com a terceira inoculação. Resposta específica contra BHV-1.2a foi detectada pelo menos até 12 meses após a primeira inoculação, entretanto, a resposta sorológica contra o BHV-5 foi de menor intensidade e duração do que aquela contra o BHV-1.2a.

Background Essential oils are complex systems which consist mainly of volatile compounds of lipophilic source, as terpenes, sesquiterpenes and some non-terpenes [1]. Resulting from secondary metabolism, essential oil from Croton argyrophyllus (EOCA) is commonly extracted from its leaves. It is known that the essential oils from Croton species exhibit good antioxidant activity against DPPH free radical and reactive oxygen species (ROS) [2]. Several diseases are attributed to the increase of free radicals that show the importance of endogenous antioxidants like enzyme superoxide dismutase (SOD). Considering the use in folk medicine, it is relevant to find which concentration of EOCA has antioxidant effect against free radicals. To answer this question, the study aimed to evaluate ROS production in peritoneal macrophages of essential oil from C. argyrophyllus.

Desenvolveu-se a técnica de transcrição reversa - reação em cadeia pela polimerase para detectar o vírus da hepatite do camundongo em tecido hepático. Para se eliminar possíveis falhas na reação de amplificação RT-PCR usou-se um segundo ciclo de amplificação com primers internos para confirmar a especificidade e aumentar a sensibilidade do teste. Após a optimização do protocolo, descreve-se a detecção da amplificação específica da seqüência-alvo em camundongos de 18 das 20 colônias examinadas. _________________________________________________________________________________________ ABSTRACT: A reverse transcriptase polymerase chain reaction (RT-PCR) to detect mouse hepatitis virus (MHV) in hepatic tissue was developed. To circumvent possible failures in RT-PCR amplifications, a second round of PCR with internal primers was used to confirm the specificity and increase the sensitivity of the test. Using this method specific amplification of MHV sequences was observed in 18 out of 20 mouse colonies examined.

Uma amostra brasileira do vírus da doença de Aujeszky, isolada de um leitão, foi estudada quanto à virulência para suínos e seu genoma analisado no que se refere ao padrão de fragmentação pela enzima de restrição Bam HI. Leitões com 50 dias de idade, sorologicamente negativos, expostos a essa amostra, não mostraram sinais de doença e o vírus foi detectado na região orofaríngeana durante pelo menos três dias após exposição. Com base no padrão de migração dos fragmentos de restrição, o isolamento foi classificado como pertencente ao grupo I da classificação proposta por Herrmann. Infecção latente foi detectada por PCR em todos os suínos. Algumas variações foram identificadas no mapa físico de Bam HI da amostra ASB Piau quando se comparou com o mapa obtido da amostra virulenta brasileira LA031. _________________________________________________________________________________________ ABSTRACT: One Brazilian strain of Aujeszky’s disease virus isolated from a piglet in which the disease had not been observed was studied as for its virulence in pigs. The genome of the virus was molecularly analysed as for their restriction endonuclease cleavage pattern. Fifty-day-old non-immune weanlings exposed to this strain showed no disease although the virus was present in their oropharyngeal area for at least three days. All animals developed moderate titers of neutralizing antibody. Based on number of bands and migration rate of restriction fragments the isolate was classified into Herrmann’s type I group. Latent infection was detected in all pigs by PCR. Some variations were detected in the cleavage pattern of the strain ASB Piau when compared to LA031 virulent Brazilian strain, that could be related to differences in the virulence.

A DNA hybridization dot-blot assay using a radioactive and a non-radioactive probe has been developed for the detection of Aujeszky's disease virus (ADV). The Bam H I 7 fragment of ADV genomic DNA was labeled by nick translation using 32P-dCTP and the 196bp polymerase chain reaction (PCR) gG glycoprotein gene amplified fragment was also labeled by nick translation but using biotin d-7-dATP. This technique provides a fast and effective means of detecting acute cases of ADV infection but it was unable to detect ADV nucleic acid sequences in trigeminal nerve ganglia of latent infected pigs and mice.

DNA-based immunization has initiated a new era of vaccine research. One of the main goals of gene vaccine development is the control of the levels of expression in vivo for efficient immunization. Modifying the vector to modulate expression or immunogenicity is of critical importance for the improvement of DNA vaccines. The most frequently used vectors for genetic immunization are plasmids. In this article, we review some of the main elements relevant to their design such as strong promoter/enhancer region, introns, genes encoding antigens of interest from the pathogen (how to choose and modify them), polyadenylation termination sequence, origin of replication for plasmid production in Escherichia coli, antibiotic resistance gene as selectable marker, convenient cloning sites, and the presence of immunostimulatory sequences (ISS) that can be added to the plasmid to enhance adjuvanticity and to activate the immune system. In this review, the specific modifications that can increase overall expression as well as the potential of DNA-based vaccination are also discussed.

A Virologia proporciona conhecimentos básicos e aplicados para serem utilizados no dia-a-dia das pessoas visando melhorar sua qualidade de vida no tocante à saúde coletiva. Entretanto, há uma carência muito grande de estudos que analisam esses conceitos nos livros didáticos do ensino médio. Esta pesquisa analisou os principais conceitos da Virologia nos livros didáticos de Biologia do ensino médio mais utilizados em escolas do município de Aracaju, Sergipe. A análise foi feita com ênfase na verificação de erros conceituais e em uma possível consideração do conhecimento prévio dos alunos. Os livros apresentaram problemas com relação aos conceitos empregados e à contextualização. Os resul tados obtidos indicam a necessidade de reformulação e atualização desses recursos didáticos para o auxílio no ensino da Virologia. The study of viruses provides basic and applied knowledge to be used in people's daily actions aimed at the improvement of the quality of life concerning collective health. However, there is a considerable lack of studies that analyze those concepts in the high school textbooks. This research analyzed the main concepts of the Virology in high school Biology textbooks widely used at schools of Aracaju, Sergipe state. The analysis was made with emphasis on the verification of conceptual mis takes whereas taking into consideration the students' previous knowledge. The books presented problems regarding the applied concepts and con- textualization. The obtained results indicate a need for the reformulation and updating of those didactic resources with a view to assist in the teach ing of Virology.