Existem diversos trabalhos publicados sobre a utilização de diferentes métodos imunológicos para diagnosticar infecções do trato respiratório causadas por vírus parainfluenza bovino tipo 3 (bPIV-3). Entretanto, é escassa a literatura sobre a utilização da técnica de isolamento viral. Até o presente momento não havia sido relatada a utilização da Transcrição Reversa - Reação em Cadeia da Polimerase (RT-PCR), na detecção de bPIV-3. O objetivo deste estudo foi contribuir para uma melhor caracterização dos bPIV-3 através do desenvolvimento de técnicas de RTPCR para a sua detecção. Utilizando-se uma amostra referência de bPIV-3 (SF-4) e uma amostra de bPIV-3 isolada no Rio Grande do Sul (amostra DIO) foram desenvolvidas técnicas de RT-PCR para a amplificação de diferentes regiões do gene da hemaglutinina-neuraminidase (HN). Após seqüenciamento parcial do gene HN e alinhamento das seqüências da amostra DIO, os resultados revelaram homologia de 99% em relação à amostra referência, 98% a 91% quando comparada com outras amostras de bPIV-3 previamente publicadas na rede e 79% a 80% quando comparada com as amostras de hPIV-3. Foi desenvolvida, também, uma técnica de RT-PCR para amplificação de parte do gene da HN do bPIV-3 e do hPIV-3. Nos experimentos de otimização, a técnica de RT-PCR, comparada com o isolamento viral, apresentou sensibilidade de 140 DICC50, boa especificidade e reprodutibilidade. Os resultados, após seqüenciamento da amostra de vírus bPIV-3 isolada no RS, apresentaram, grande homologia com os das amostras de bPIV-3 comparadas, especialmente a amostra referência. Os dados obtidos neste estudo mostraram que a RT-PCR desenvolvida para a detecção de PIV-3 foi capaz de amplificar um fragmento de 1009 bp do gene da HN de amostras de PIV-3 isoladas de bovinos e humanos, possibilitando a sua utilização em diagnóstico e em estudos epidemiológicos. / There are several published studies on the application of different immunological methods for diagnosis of respiratory infections caused by bovine type 3 Parainfluenza virus (bPIV-3). However, the literature on viral isolation procedure is very scarce. At present there is no report about the utilization of reverse transcription-polymerase chain reaction (RT-PCR) for bPIV-3 detection. The aim of this study was to contribute to a better caracterization of bovine type 3 Parainfluenza virus by developing RT-PCR techniques to its detection. A reference sample (SF-4) and a sample of bPIV-3 isolated in Rio Grande do Sul (DIO sample) were used to develop RT-PCR techniques by amplification of different regions of hemagglutinin-neuraminidase gene (HN). After HN gene partial sequencing of DIO sample and sequence alignment, the results revealed 99% homology when compared to reference sample, 98% the 91% homology in relation to bPIV-3 samples previously published and 79% the 80% if compared to hPIV-3 samples. It was also developed a RT-PCR for amplification of a part of bPIV-3 and hPIV-3 NH gene. In optimization experiments, compared to viral isolation procedure, the RTPCR displayed a sensitivity of 140 DICC50, good specificity and reproductibility. Results after sequencing of bPIV-3 sample isolated in RS displayed strong homology with those of bPIV-3 tested samples, specially the reference sample. Data obtained in this study showed that the RT-PCR technique developed for PIV- 3 detection was able to amplify an 1009 bp HN gene fragment of bovine and human PIV-3 samples which enables its utilization in diagnostic and epidemiological studies.

Existem diversos trabalhos publicados sobre a utilização de diferentes métodos imunológicos para diagnosticar infecções do trato respiratório causadas por vírus parainfluenza bovino tipo 3 (bPIV-3). Entretanto, é escassa a literatura sobre a utilização da técnica de isolamento viral. Até o presente momento não havia sido relatada a utilização da Transcrição Reversa - Reação em Cadeia da Polimerase (RT-PCR), na detecção de bPIV-3. O objetivo deste estudo foi contribuir para uma melhor caracterização dos bPIV-3 através do desenvolvimento de técnicas de RTPCR para a sua detecção. Utilizando-se uma amostra referência de bPIV-3 (SF-4) e uma amostra de bPIV-3 isolada no Rio Grande do Sul (amostra DIO) foram desenvolvidas técnicas de RT-PCR para a amplificação de diferentes regiões do gene da hemaglutinina-neuraminidase (HN). Após seqüenciamento parcial do gene HN e alinhamento das seqüências da amostra DIO, os resultados revelaram homologia de 99% em relação à amostra referência, 98% a 91% quando comparada com outras amostras de bPIV-3 previamente publicadas na rede e 79% a 80% quando comparada com as amostras de hPIV-3. Foi desenvolvida, também, uma técnica de RT-PCR para amplificação de parte do gene da HN do bPIV-3 e do hPIV-3. Nos experimentos de otimização, a técnica de RT-PCR, comparada com o isolamento viral, apresentou sensibilidade de 140 DICC50, boa especificidade e reprodutibilidade. Os resultados, após seqüenciamento da amostra de vírus bPIV-3 isolada no RS, apresentaram, grande homologia com os das amostras de bPIV-3 comparadas, especialmente a amostra referência. Os dados obtidos neste estudo mostraram que a RT-PCR desenvolvida para a detecção de PIV-3 foi capaz de amplificar um fragmento de 1009 bp do gene da HN de amostras de PIV-3 isoladas de bovinos e humanos, possibilitando a sua utilização em diagnóstico e em estudos epidemiológicos. / There are several published studies on the application of different immunological methods for diagnosis of respiratory infections caused by bovine type 3 Parainfluenza virus (bPIV-3). However, the literature on viral isolation procedure is very scarce. At present there is no report about the utilization of reverse transcription-polymerase chain reaction (RT-PCR) for bPIV-3 detection. The aim of this study was to contribute to a better caracterization of bovine type 3 Parainfluenza virus by developing RT-PCR techniques to its detection. A reference sample (SF-4) and a sample of bPIV-3 isolated in Rio Grande do Sul (DIO sample) were used to develop RT-PCR techniques by amplification of different regions of hemagglutinin-neuraminidase gene (HN). After HN gene partial sequencing of DIO sample and sequence alignment, the results revealed 99% homology when compared to reference sample, 98% the 91% homology in relation to bPIV-3 samples previously published and 79% the 80% if compared to hPIV-3 samples. It was also developed a RT-PCR for amplification of a part of bPIV-3 and hPIV-3 NH gene. In optimization experiments, compared to viral isolation procedure, the RTPCR displayed a sensitivity of 140 DICC50, good specificity and reproductibility. Results after sequencing of bPIV-3 sample isolated in RS displayed strong homology with those of bPIV-3 tested samples, specially the reference sample. Data obtained in this study showed that the RT-PCR technique developed for PIV- 3 detection was able to amplify an 1009 bp HN gene fragment of bovine and human PIV-3 samples which enables its utilization in diagnostic and epidemiological studies.

Existem diversos trabalhos publicados sobre a utilização de diferentes métodos imunológicos para diagnosticar infecções do trato respiratório causadas por vírus parainfluenza bovino tipo 3 (bPIV-3). Entretanto, é escassa a literatura sobre a utilização da técnica de isolamento viral. Até o presente momento não havia sido relatada a utilização da Transcrição Reversa - Reação em Cadeia da Polimerase (RT-PCR), na detecção de bPIV-3. O objetivo deste estudo foi contribuir para uma melhor caracterização dos bPIV-3 através do desenvolvimento de técnicas de RTPCR para a sua detecção. Utilizando-se uma amostra referência de bPIV-3 (SF-4) e uma amostra de bPIV-3 isolada no Rio Grande do Sul (amostra DIO) foram desenvolvidas técnicas de RT-PCR para a amplificação de diferentes regiões do gene da hemaglutinina-neuraminidase (HN). Após seqüenciamento parcial do gene HN e alinhamento das seqüências da amostra DIO, os resultados revelaram homologia de 99% em relação à amostra referência, 98% a 91% quando comparada com outras amostras de bPIV-3 previamente publicadas na rede e 79% a 80% quando comparada com as amostras de hPIV-3. Foi desenvolvida, também, uma técnica de RT-PCR para amplificação de parte do gene da HN do bPIV-3 e do hPIV-3. Nos experimentos de otimização, a técnica de RT-PCR, comparada com o isolamento viral, apresentou sensibilidade de 140 DICC50, boa especificidade e reprodutibilidade. Os resultados, após seqüenciamento da amostra de vírus bPIV-3 isolada no RS, apresentaram, grande homologia com os das amostras de bPIV-3 comparadas, especialmente a amostra referência. Os dados obtidos neste estudo mostraram que a RT-PCR desenvolvida para a detecção de PIV-3 foi capaz de amplificar um fragmento de 1009 bp do gene da HN de amostras de PIV-3 isoladas de bovinos e humanos, possibilitando a sua utilização em diagnóstico e em estudos epidemiológicos. / There are several published studies on the application of different immunological methods for diagnosis of respiratory infections caused by bovine type 3 Parainfluenza virus (bPIV-3). However, the literature on viral isolation procedure is very scarce. At present there is no report about the utilization of reverse transcription-polymerase chain reaction (RT-PCR) for bPIV-3 detection. The aim of this study was to contribute to a better caracterization of bovine type 3 Parainfluenza virus by developing RT-PCR techniques to its detection. A reference sample (SF-4) and a sample of bPIV-3 isolated in Rio Grande do Sul (DIO sample) were used to develop RT-PCR techniques by amplification of different regions of hemagglutinin-neuraminidase gene (HN). After HN gene partial sequencing of DIO sample and sequence alignment, the results revealed 99% homology when compared to reference sample, 98% the 91% homology in relation to bPIV-3 samples previously published and 79% the 80% if compared to hPIV-3 samples. It was also developed a RT-PCR for amplification of a part of bPIV-3 and hPIV-3 NH gene. In optimization experiments, compared to viral isolation procedure, the RTPCR displayed a sensitivity of 140 DICC50, good specificity and reproductibility. Results after sequencing of bPIV-3 sample isolated in RS displayed strong homology with those of bPIV-3 tested samples, specially the reference sample. Data obtained in this study showed that the RT-PCR technique developed for PIV- 3 detection was able to amplify an 1009 bp HN gene fragment of bovine and human PIV-3 samples which enables its utilization in diagnostic and epidemiological studies.

Masters of Science / The rapidly expanding field of nanotechnology has been the focus of many biologists with regard to drug delivery. The ability of nanoparticles to enter cellular compartments makes it possible to explore specific treatment strategies for life-threatening diseases such as AIDS. Since HIV primarily infects CD4+ cells, we aim to use CD4 as a selectable marker to deliver pro-apoptotic nano-devices to HIV infected cells. The objective is to selectively induce cell death or apoptosis in CD4+ HIV infected cells. Apoptosis is activated through a number of biochemical pathways. The apoptosis promoting protease, caspase-3 is central to the induction of apoptosis. Caspase-3 is produced as an inactive zymogen and is activated by other proteases through proteolytic cleavage. We take advantage of the fact that HIV-infected cells produce HIV-1 protease, which is responsible for the production of infectious virions through proteolytic cleavage of the HIV proteins, Gag and Pol. Our strategy was to generate a mutant form of the caspase-3 protease that is only cleavable by HIV-1 protease.

No description available.

Follicular dendritic cells (FDCs) reside in the lymphoid follicles of the secondary lymphoid tissues (sLTs). Following the infection of an individual with human immunodeficiency virus type 1 (HIV-1), viral particles are trapped in massive quantities on the surfaces of FDCs. HIV-1 viral compartments are cell types or tissues between which there is a restriction of virus flow. Compartmentalization of HIV-1 creates numerous sites within the body in which the virus can undergo independent evolution, giving rise to a more diverse total viral population. Given the sessile nature of the FDC, I hypothesized that contrary to common assumptions, FDC-trapped HIV-1 is compartmentalized between different sLTs. Furthermore, given that FDC-trapped HIV-1 represents the major source of virus in the host, I postulated that this compartmentalization would likely impact the diversity of HIV-1 associated with the sLTs. I isolated FDCs, macrophages, and T cells from various sLTs, and sequenced cloned HIV-1 associated with these three cell populations. I subjected the resulting DNA and cDNA sequence data to phylogenetic and other statistical analyses. In support of my hypothesis, I demonstrate that both HIV-1 gp120 and pol sequences cloned from FDCs are compartmentalized between different sLTs. This compartmentalization is even apparent between lymph nodes taken from the same lymph node chain. One of the apparent effects of this compartmentalization is to significantly increase the viral genetic diversity in multiple sLTs when compared with diversity in a single sLT. It also appears that the selective pressures on HIV-1 differ among the sLTs. In addition, when proviruses isolated from macrophages from different sLTs were compared, it was also evident that there is compartmentalization of HIV-1 associated with this cell type as well. Finally, I demonstrate that HIV-1 isolated from an unfractionated population of cells from a single sLT, may be an inadequate representation of the total viral population in that sLT. Taken together, my data suggest that the nature of HIV-1 in the sLTs may be more complex than currently appreciated.

No description available.

No description available.

No description available.

Objectives: The description of the raccoon rabies epizootic in Virginia over fifteen years (1989-2003). Methods: Using simple statistical methods and a geographic information system (GIS)-based approach, and fifteen years worth of animal surveillance data, the progress of this epizootic has been charted in terms of the geographic spread of the disease, the major animal species affected by the disease and its spread, and the exposure and risk to humans and livestock animals presented by the expansion of the geographic range. Results: The resulting descriptive study illustrates the eastward expansion of the epizootic, the mushrooming of the disease in the northern region of the state, and the rates of rabid animal submissions for every health district and selected important animal species. Human exposures to rabid animals are mapped and compared to human population densities. Strong seasonal trends in human and livestock exposures to rabid animals are illustrated, with animal exposures predominating in the spring and autumn, while human exposures peak in the summer; also shown is the possible emergence of new strains of rabies virus and the possible extinction of the previously dominant strain. Conclusions: Some potentially positive developments have been found, such as substantially increasing levels of bat submissions across time, which may signify greater public awareness of the disease. Serious deficiencies in the monitoring system are discussed, centering on the accuracy and comparability of the data collected, and suggestions for improvement are offered. While several potentially interesting new areas of study are put forward, the standard approach to rabies control (pet vaccination and control, education of at-risk populations, orally vaccinating wild animals) is not found to be in need of significant modification, aside from the specifics of the approach being tailored to better meet local conditions.