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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Vulnerabilidade de adolescentes ao HIV/AIDS: revisão integrativa / Vulnerability elements to HIV/AIDS among adolescents: integrative review

Toledo, Melina Mafra 14 May 2008 (has links)
Introdução: A adolescência é um dos períodos mais intensos da vida, pelos desafios, descobertas e oportunidades de exploração nela presentes e, por isso, se constitui um determinante da vulnerabilidade ao HIV/AIDS. Objetivo: identificar as evidências científicas da literatura sobre os elementos da vulnerabilidade de adolescentes ao HIV/AIDS. Metodologia: Revisão sistemática da literatura, na modalidade de denominada revisão integrativa. A busca de dados foi realizada nas seguintes bases e bancos de dados: CINAHL, PUBMED, SCOPUS, LILACS, ADOLEC, DEDALUS, Biblioteca Digital de Teses e Dissertações -BDTD, portal de teses da USP, no período de 1996 a 2006. Após avaliação do rigor metodológico dos estudos previamente selecionados, foram incluídos como amostra para análise 41 estudos realizados em diferentes países. Resultados: foram apresentados em duas etapas: a caracterização dos estudos e as evidências científicas dos elementos de vulnerabilidade. Os elementos identificados são iguais ou muito semelhantes nos diferentes países em que foram realizados os estudos, sendo diferente a forma como a vulnerabilidade se expressa, bem como a associação entre os elementos que a compõem. Foram identificados 33 elementos de vulnerabilidade, agrupados segundo três temas centrais: \"comportamentos e conhecimentos sobre o HIV/AIDS\", \"normas sociais\", \"condições socioeconômicas\" e \"gestão de serviços de saúde\". Os elementos da dimensão individual foram identificados com maior freqüência, seguidos pelos da dimensão social e programática. Os elementos da dimensão individual foram: grau e qualidade das informações que o adolescente possui sobre HIV, capacidade de assimilar e incorporar essas informações a sua vida, desconhecimento de sua vulnerabilidade, confiança na monogamia do parceiro, não adoção de práticas de proteção, uso de drogas, recusa ou incômodo em utilizar o preservativo, dificuldade de negociação de adolescentes femininas sobre uso do preservativo, gravidez como maior preocupação da conseqüência do ato sexual desprotegido, relações de gênero, representações da aids (doença do outro). Na dimensão social identificou-se: pobreza, violação dos direitos humanos, relações de gênero (aspectos culturais, exploração sexual, prostituição como meio sobrevivência), esgarçamento de laços familiares, acesso aos meios de escolarização e informação, desemprego, violência e falta de expectativas quanto ao futuro. Os elementos da dimensão programática envolveram: relação entre o usuário adolescente e o profissional (discriminação), qualidade do aconselhamento, teste para HIV, acessibilidade aos serviços de saúde, (descontinuidade das ações preventivas e falta de integração com outros serviços no planejamento e desenvolvimento das ações). Conclusões: a revisão integrativa permitiu identificar evidências científicas dos elementos constantes das três dimensões da vulnerabilidade, descritas no conceito de vulnerabilidade, assim como outros elementos, como a falta de percepção do adolescente sobre sua vulnerabilidade ao HIV/AIDS e a falta de perspectiva quanto ao futuro. A contribuição deste estudo para as práticas de saúde é relevante, uma vez que explicitou por meio das evidências científicas, os elementos da vulnerabilidade do adolescente ao HIV/AIDS, que devem ser considerados no planejamento das ações de prevenção para esse segmento social. Além disso, permitiu identificar lacunas de conhecimento sobre a temática, bem como a qualidade do conhecimento produzido, que também devem ser levados em conta em pesquisas futuras / Introduction: Adolescence is one of the most intense periods of life, because of the challenges, discoveries and chances that are present, and it is also a period of vulnerability infection to HIV. Objective: This study\'s goal is to identify the scientific evidences of literature on the elements of vulnerability of adolescents to the HIV/AIDS. Method: Systematic literature review called integrative review. The search of data was carried through in the following bases and data bases: CINAHL, PubMed, SCOPUS, LILACS, ADOLEC, DEDALUS, Capes- BDTD, portal of thesis of USP, in the period of 1996 to 2006. 661 studies, carried out in different countries, were previously selected to be evaluated for its methodology rigor. After evaluation the methodological rigor of the studies previously selected 41 of those studies were chosen as sample. Results: Where presented in two stages: the characterization of the studies and the scientific evidences of the vulnerability elements. The identified elements were equal or very similar, in the different countries where the studies had been carried through, being different the way that vulnerability was expressed as well as the association between such elements. Thirty- three elements of the vulnerability had been identified and grouped according to the central subject of each element: \"social behaviors and knowledge about HIV/AIDS\", \"social rules\", \" socioeconomical conditions \"and \"management of health services\". The elements of the subjective dimension were identified more frequently, followed by the ones of the social and programmatical dimension. The elements of the individual dimension were: the how much adolescent learns about aids ; the ability to assimilate and incorporate this knowledge to his/her your life; not knowing that he/she is vulnerable; trusting in his partner\'s monogamy; not adopting protection practices; use of drugs, uncomfortable or refusal to use condoms; difficulty in negotiating with her partner on the use of condom; pregnancy as the most undesirable consequence of the unprotected sexual act; gender relations; aids like a disease of other. The following social elements were identified: poverty; human rights violation; gender relations (cultural aspects), sexual exploitation (prostitution as a way of living) weakening of family bonds; access to school and information; unemployment, violence and hopelessness in the future. The following programmatical elements, are pointed out: relation between the adolescent patient and the health professional (discrimination); quality of counseling, testing for HIV, accessibility to health services, lack of preventive actions and lack of integration with other services in planning and development prevention actions for this social segment. Conclusions: This integrative review allowed identifying scientific evidences of vulnerability elements in the three dimensions, described in the vulnerability concept, as well as other elements, like the lack of perception of the adolescent on their own vulnerability to HIV/AIDS infection and the lack of perspective about their future. The contribution of this study for the health practices is relevant, once had proved by means of the scientific evidences, the elements of the vulnerability of the adolescent to the HIV/AIDS, that must be considered in the planning of the actions prevention for this social segment. Moreover, it allowed to identify knowledge gaps on the thematic one, as well as the quality of the produced knowledge, that also must been considered in future research
122

Mutation of Regnase-1 causes primary immunodeficiency associated with auto-inflammatory disease

Hashim, Ilie January 2017 (has links)
Primary immunodeficiencies (PIDs) are a heterogeneous group of disorders causing immune dysfunction that manifest with increased susceptibility to infection. Some PID patients may also have autoimmune and autoinflammatory manifestations. In many cases, PIDs are monogenic disorders that follow Mendelian inheritance and mutations in more than 250 genes have been shown to cause PIDs. However, in the majority of PID patients the causative mutations remain unknown. Here I report a study of a patient from a consanguineous family who presented in infancy with colitis, autoimmune hepatitis, autoimmune anemia and thrombocytopenia. The patient also suffered recurrent respiratory infections leading to bronchiectasis and had several episodes of severe varicella zoster virus (VZV) infections, including pneumonia and meningitis. Immunologically, the patient had increased IgM and IgG levels, absent IgA, low specific antibodies and multiple auto-antibodies, including anti-Interferon- antibodies. Whole blood stimulation assays identified an increased production of the pro-inflammatory cytokine IL-6. Throughout his life the patient received immunosuppressive therapy. Whole exome sequencing of the patient discovered a homozygous frameshift mutation in the ZC3H12A gene that encodes the Regnase-1 protein also known as MCPIP1. Regnase-1 is a regulatory RNase that directly degrades mRNAs of several pro-inflammatory genes, e.g. mRNA of cytokine IL-6, thus curbing the immune activation. The presentation of the patient resembled the phenotype of the Regnase-1-knockout mice that developed spontaneous systemic inflammation, disorganisation of lymphoid organs, severe anaemia and hyperimmunoglobulinemia, with the increased production of IL-6. I studied expression of the mutant Regnase-1 protein using commercial antibodies; also a new custom-made antibody that detects the truncated mutant Regnase-1 protein was developed. Analysis of the patient-derived cells demonstrated absence of the full-length Regnase-1 protein. Cloning and forced expression of the truncated mutant protein showed that it is mislocalized inside the cells and is functionally impaired. Studies of the iPSC-derived macrophages, EBV-transformed B cells and primary fibroblasts of the patient demonstrated increased levels of the IL-6 mRNA in the resting cells. They also showed impaired regulation of the truncated mutant Regnase-1 protein and IL-6 mRNA levels after cell stimulation. Mutations in Regnase-1 have never been associated with human diseases previously. Therefore, this study describes a novel PID caused by the Regnase-1 deficiency.
123

Cardiovascular disease in human immunodeficiency virus-infection as a cause of hospitalization: a case-series in a General Hospital in Peru

Valenzuela Rodríguez, Germán, Mezones Holguín, Edward, Mendo Urbina, Fernando, Rodríguez Morales, Alfonso J. 22 April 2015 (has links)
Background Cardiovascular disease in the context of human immunodeficiency virus infection has become a major clinical concern in recent years. In the current report we assess hospitalizations due to cardiovascular disease in human immunodeficiency virus patients in a Social Security reference hospital in Peru. Methods A retrospective study was carried out between January 1996 and December 2012 in a General Hospital in Lima, Peru. Results We included 26 patients hospitalized due to cardiovascular disease. Mean age was 46.3 years (SD 12.5), predominantly male (57.7%). Ten patients (38.4%) were in Acquired Immunodeficiency Syndrome stages. Seventeen (65.4%) received high-active-antiretroviral therapy. Eleven (42.3%) had cardiac involvement and 15 (57.7%) had non-cardiac vascular involvement. The most frequent causes of cardiac involvement were pericardial effusion and myocardial infarction. On the other hand, deep vein thrombosis and stroke were the most frequent for non-cardiac vascular involvement. Conclusions Cardiovascular disease is an important cause of hospitalization in Peruvian human immunodeficiency virus patients, with differences between immunosuppression stages. Further studies analyzing associated factors are warranted. / germanvrodriguez@yahoo.com / Revisión por pares
124

CÃrculo de cultura com jovens usuÃrios de cocaÃna/crack visando à prevenÃÃo do hiv/aids. / Culture circle with adolescent cocaine/crack users aimed at prevention of hiv / aids.

Agnes Caroline Souza Pinto 17 January 2013 (has links)
nÃo hà / Desde que a SÃndrome da ImunodeficiÃncia Adquirida (AIDS) comeÃou a ser reconhecida como problema de saÃde pÃblica, tem havido preocupaÃÃo crescente com o papel desempenhado pelos usuÃrios de drogas na disseminaÃÃo global do VÃrus da ImunodeficiÃncia Adquirida (HIV), sendo esta, atualmente, a segunda causa de morte entre eles. O estudo apresenta como objetivo geral promover, por meio dos CÃrculos de Cultura, espaÃo crÃtico-reflexivo acerca da prevenÃÃo do HIV/aids junto aos jovens usuÃrios de cocaÃna/crack. Trata-se de pesquisa-aÃÃo, realizada de janeiro a setembro de 2012. Os sujeitos do estudo foram dez jovens usuÃrios de cocaÃna/crack, do sexo masculino, com idade entre 18 e 24 anos, acompanhados para tratamento de dependÃncia na comunidade terapÃutica Desafio Jovem do CearÃ. Os instrumentos e as tÃcnicas utilizados para coleta das informaÃÃes foram: entrevista semiestruturada, observaÃÃo-participante, registro fotogrÃfico, gravaÃÃo dos discursos e registro em diÃrio de campo. Como mÃtodo e tÃcnica para articular a dimensÃo coletiva e interativa da investigaÃÃo proposta pela pesquisa-aÃÃo, utilizou-se o CÃrculo de Cultura. Deste modo, foram realizados seis CÃrculos de Cultura construÃdos de acordo com as seguintes etapas: o conhecer do universo individual e coletivo, seleÃÃo dos temas, dinÃmicas de sensibilizaÃÃo e problematizaÃÃo, reflexÃo teÃrico-prÃtica, construÃÃo coletiva do conhecimento e avaliaÃÃo de cada cÃrculo. Neste sentido, os jovens discutiram e refletiram sobre: o viver dos jovens com as drogas, a vulnerabilidade do usuÃrio de drogas ao HIV/aids, a relaÃÃo da Aids com as drogas, a prevenÃÃo e a transmissÃo do HIV/aids e o que aprendemos sobre Aids? Os resultados dessas discussÃes foram os seguintes: no inÃcio dos cÃrculos, os jovens demonstraram conhecimento sobre a aids bastante incipiente e desarticulado, com predominÃncia de mitos; relataram nunca terem feito uso de drogas injetÃveis, porÃm se consideravam vulnerÃveis Ãs DST/aids visto que o compartilhamento de canudos e cachimbos para o uso da cocaÃna/crack e a perda da consciÃncia favoreciam ao nÃo uso do preservativo durante as relaÃÃes sexuais e à multiplicidade de parceiros; os amigos desses jovens foram os principais fatores de risco para que viessem a experimentar as drogas; as festas, as âravesâ eram lugares propÃcios para o inÃcio do uso de drogas, porÃm casas abandonadas, escolas, e casas dos amigos, tambÃm foram incluÃdas como opÃÃes para o consumo de drogas, e que a religiÃo era muito importante para que os jovens decidissem nÃo usar mais as drogas e iniciassem o tratamento para dependÃncia. O processo educativo despertou nos nossos jovens o interesse e a necessidade de conversar com seus pares acerca da problemÃtica que envolvia as DST/aids e as drogas, e alÃm disso ensinou vÃrias maneiras de trabalhar a questÃo das drogas nas escolas com crianÃas e adolescentes que ainda nÃo sÃo usuÃrios, ratificando que o cÃrculo possibilita a reflexÃo e a transformaÃÃo do sujeito e do meio no qual ele està inserido. Diante do exposto, o enfermeiro pode trabalhar com metodologias dialÃgicas e participativas, como a de Paulo Freire, para favorecer a reflexÃo crÃtica do educador e educando em prol da prevenÃÃo de DST/aids em usuÃrios de cocaÃna/crack.
125

Adolescentes vÃtimas de violÃncia sexual: crenÃas e valores relacionados à prevenÃÃo das doenÃas sexualmente transmissÃveis e a AIDS / Adolescent victims of sexual violence: beliefs and values related to the prevention of sexually transmitted diseases and AIDS

Kelanne Lima da Silva 13 December 2011 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A violÃncia sexual caracteriza-se como um grave problema de saÃde pÃblica que acarreta distÃrbios no desenvolvimento biopsicossocial e sexual de suas vÃtimas, principalmente quando essa agressÃo ocorre na fase da adolescÃncia, pois esses sujeitos se encontram numa etapa da vida marcada por mudanÃas e adaptaÃÃes, especialmente no Ãmbito da sexualidade. Portanto, as crenÃas e valores das vitimas de violÃncia sexual precisam ser compreendidas para promover a adoÃÃo de comportamentos sexuais saudÃveis. Objetivou-se compreender como as crenÃas e valores das adolescentes vitimas de violÃncia sexual influenciam no comportamento de prevenÃÃo das DST e da AIDS com base no Modelo de CrenÃas em SaÃde (MCS) . Trata-se de uma pesquisa qualitativa, descritiva, realizada numa InstituiÃÃo de Acolhimento no Municipal de Fortaleza, no perÃodo de maio a julho de 2011, com oito adolescentes vitimas de violÃncia sexual. Foram utilizados como instrumentos e procedimentos para a coleta de informaÃÃes: a observaÃÃo participante de todos os encontros, que foram registrados no diÃrio de campo; todo o material produzido durante os grupos focais, como cartazes, desenhos, entre outros; e a transcriÃÃo da gravaÃÃo dos diÃlogos durante as estratÃgias de grupo e do roteiro de entrevista semiestruturada. As informaÃÃes foram organizadas conforme as dimensÃes do MCS. Todos os aspectos legais e Ãticos da pesquisa envolvendo os seres humanos foram respeitados. Inicialmente, foi necessÃrio caracterizar as participantes do estudo e observou-se que as histÃrias de vida dessas adolescentes estavam condizentes com a literatura. Em relaÃÃo Ãs categorias criadas conforme o MCS: as adolescentes tem um dÃfice de conhecimento em relaÃÃo a essas doenÃas e nÃo se consideraram susceptÃveis as DST/AIDS por acreditarem que nÃo irÃo se relacionar sexualmente com homens, mesmo identificando a maior vulnerabilidade da mulher a essas patologias; em relaÃÃo à percepÃÃo da gravidade, elas classificaram essas doenÃas como graves, incurÃveis e que alteram o convÃvio social, demonstrando medo de contrair uma dessas patologias; identificaram como benefÃcios e barreiras do mÃtodo preventivo ser de fÃcil acesso e utilizaÃÃo e prevenir tanto doenÃas como gravidez, mas interferem no prazer sexual; e seu uso està relacionado com questÃes culturais e sociais, ressalta-se tambÃm, que o abuso de Ãlcool e drogas intervÃm na adoÃÃo de comportamentos saudÃveis. Conclui-se que as crenÃas e valores dessas adolescentes as tornam vulnerÃveis a DST/AIDS, sendo necessÃrio refletir sobre as consequÃncias da violÃncia sexual na vida dessas adolescentes para a elaboraÃÃo de estratÃgias e aÃÃes preventivas voltadas para esse publico-alvo no que concerne ao desenvolvimento da sexualidade de forma segura, minimizando traumas e sofrimentos advindos dessa experiÃncia na vida dessas adolescentes, tornando-as conscientes dos seus direitos sexuais e reprodutivos. / Sexual assault is characterized as a serious public health problem that leads to disorders in the bio-psychosocial and sexual development of the victims, especially when the aggression happens in adolescence, because these subjects are in a stage of life marked by changes and adaptations, especially concerning sexuality. Therefore, the values and beliefs of the victims of sexual assault must be understood to promote the adoption of a healthy sexual behavior. It was aimed to understand how beliefs and values of adolescent victims of sexual assault influence the behavior of prevention of STD/AIDS based on the Health Belief Model. It is a qualitative descriptive research carried out at a Host Institution in the City of Fortaleza from May to July 2011 with eight adolescent victims of sexual assault. Using as tools and procedures for data collection: participant observation of all meetings, which were registered in a field diary; all the material produced during the focus groups, such as posters, drawings, among others; and the transcription of the dialogue recording during the group strategies and semi-structured interviews. The information was organized according to the Health Belief Model dimensions. All legal and ethical aspects of researches involving human beings were respected. Initially, it was necessary to characterize the study participants and it was found that the life stories of these adolescents were consistent with the literature. Regarding the categories created according to the Health Belief Model: the adolescents lack knowledge about these diseases and don't considered them susceptible to STD/AIDS because they believe that they will not relate sexually with men, in spite identifying the greater vulnerability of women to such pathologies; concerning the perception of gravity, they classified these diseases as serious, incurable, and that changes social life, demonstrating fear of contracting these diseases; they identified as benefits and barriers of preventive method: it is easy to access and use, and prevents both diseases as pregnancy, but interferes with sexual pleasure; and its use is related to cultural and social issues, we also emphasize that the abuse of alcohol and drugs interferes in the adoption of healthy behaviors. We conclude that the beliefs and values of these adolescents make them vulnerable to STD/AIDS, being necessary to reflect on the consequences of sexual violence in their lives to build strategies and preventive actions aimed at this target audience in terms of a safe development of sexuality, minimizing trauma and suffering resulting from this experience in their lives, making them aware of their sexual and reproductive rights.
126

Assessing the Health-Related Service Needs of People Living With Human Immunodeficiency Virus: A Review of Ryan White Title II Needs Assessments

Loo, Ryan K. 01 May 2005 (has links)
The Health Resources and Services Administration (HRSA) allocated $940 million in 2002, through Title II of the Ryan White Comprehensive AIDS Resources Emergency (CARE) Act, to help states improve the quality and availability of health related services for people living with HIV/AIDS . These resources are allocated based upon recommendations made by community planning committees, which in turn base their recommendations on HIV/AIDS needs assessments. A methodologically sound, comprehensive needs assessment is a critical component of effective resource allocation decisions. Poor needs assessments might lead to poor resource allocation decisions, which might have life-threatening consequences for people living with HIV/AIDS. Little is known about the quality of Ryan White Title II (RWTII) needs assessments. This dissertation identifies seven elements of a high quality needs assessment, which might serve as an assessment tool for funding agencies and as a guidance tool for grantees. The author uses the seven elements in a review of RWTII needs assessments to provide evidence pertaining to the current level of quality of RWTII needs assessments. The seven elements are then applied in a case study of improved practice to demonstrate how to adequately apply the key elements of a high quality needs assessment.
127

Professional nurses' perceptions of their ability to render effective nutritional care and support to people living with HIV/AIDS / Daisy Chasauka

Chasauka, Daisy January 2006 (has links)
hesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2007.
128

CD8+ T cell antiviral activity: mechanism of induction and the suppression of emerging feline immunodeficiency virus strains

Phadke, Anagha 17 September 2007 (has links)
In the present studies, the essential role of inducer cells for the induction of soluble anti-viral activity against feline immunodeficiency virus (FIV) was investigated. Induction of suppression of FIV replication was found to not strictly require autologous cells and was probably not FIV specific. Suppression was maximum when the inducer cells and the effector CD8+ T cells were in contact with each other, suggesting a potential role for membrane antigen interactions and/or cytokines in the induction process. Additionally, flow cytometry analysis demonstrated a significant increase in the percentage of CD8+ B7-1+ T cells in the peripheral blood of chronically FIV infected cats as compared with uninfected cats. Examination of the FIV V3-V4 envelope sequences from PBMC, lymph nodes and spleen from six cats chronically infected from three to six years with the molecular clone of FIV-PPR did not demonstrate viral variants specific for the tissues examined, emphasizing the critical role of the initial diversity and virulence of the infecting virus inoculum. Additionally, in vitro CD8+ T cell antiviral activity demonstrated by four of the six cats could have led to the control of virus replication in vivo, resulting in the uniform viral variants observed. Infection of specific pathogen free cats with FIV-TX53, an FIV isolate that belongs to an emerging subtype more closely related to FIV clade B, demonstrated an acute stage infection characterized by lymphoadenopathy and a viral dose dependent decline of CD4+/CD8+ T cell ratios below 1 by 11 weeks post infection. Interestingly, an expansion of CD8 low population of CD8+ T cells was observed in the infected cats. The soluble antiviral activity generated from inducer T cell stimulated CD8+ T cells from FIV-A-PPR infected cats also suppressed in vitro replication of the emerging FIV-TX53 and FIV-TX078 isolates. This is the first report demonstrating that the CD8+ T cell antiviral activity is inter-clade effective among FIV strains. As the success of a FIV vaccine could be hampered by occurrence of highly divergent viral variants in the fields, the exploitation of this innate, soluble anti-FIV activity could contribute to the design of novel, safe and complementary anti-FIV therapeutic strategies.
129

CD8+ T cell antiviral activity: mechanism of induction and the suppression of emerging feline immunodeficiency virus strains

Phadke, Anagha 17 September 2007 (has links)
In the present studies, the essential role of inducer cells for the induction of soluble anti-viral activity against feline immunodeficiency virus (FIV) was investigated. Induction of suppression of FIV replication was found to not strictly require autologous cells and was probably not FIV specific. Suppression was maximum when the inducer cells and the effector CD8+ T cells were in contact with each other, suggesting a potential role for membrane antigen interactions and/or cytokines in the induction process. Additionally, flow cytometry analysis demonstrated a significant increase in the percentage of CD8+ B7-1+ T cells in the peripheral blood of chronically FIV infected cats as compared with uninfected cats. Examination of the FIV V3-V4 envelope sequences from PBMC, lymph nodes and spleen from six cats chronically infected from three to six years with the molecular clone of FIV-PPR did not demonstrate viral variants specific for the tissues examined, emphasizing the critical role of the initial diversity and virulence of the infecting virus inoculum. Additionally, in vitro CD8+ T cell antiviral activity demonstrated by four of the six cats could have led to the control of virus replication in vivo, resulting in the uniform viral variants observed. Infection of specific pathogen free cats with FIV-TX53, an FIV isolate that belongs to an emerging subtype more closely related to FIV clade B, demonstrated an acute stage infection characterized by lymphoadenopathy and a viral dose dependent decline of CD4+/CD8+ T cell ratios below 1 by 11 weeks post infection. Interestingly, an expansion of CD8 low population of CD8+ T cells was observed in the infected cats. The soluble antiviral activity generated from inducer T cell stimulated CD8+ T cells from FIV-A-PPR infected cats also suppressed in vitro replication of the emerging FIV-TX53 and FIV-TX078 isolates. This is the first report demonstrating that the CD8+ T cell antiviral activity is inter-clade effective among FIV strains. As the success of a FIV vaccine could be hampered by occurrence of highly divergent viral variants in the fields, the exploitation of this innate, soluble anti-FIV activity could contribute to the design of novel, safe and complementary anti-FIV therapeutic strategies.
130

Reconstructing the Evolutionary History of RNA Viruses using Relaxed Molecular Clocks

Wertheim, Joel Okrent January 2009 (has links)
Teasing apart the evolutionary forces responsible for biological phenomena is difficult in the absence of a detailed evolutionary history, especially if this history is lacking a temporal component. RNA viruses, due to their rapid rate of molecular and phenotypic evolution, provide a unique biological system in which to study the temporal aspects of evolutionary processes. These types of studies are possible because of relaxed molecular clock dating techniques, which allow the rate of evolution to vary across a phylogenetic tree. The primary focus of the research presented here concerns the age of the simian immunodeficiency virus (SIV), the primate precursor to HIV. SIV has long been thought to be an ancient infection in non-human African primates, and it has been hypothesized that codivergence with its primate hosts has shaped the SIV phylogeny and resulted in a virus capable of apathogenic infection. The codivergence theory was tested by comparing the phylogeny of a group of monkeys thought to be exemplary of SIV-host codivergence to the phylogeny of their SIVs (Appendix A). These phylogenies were incongruent, suggesting that SIV may have infected these monkeys after their common ancestor speciated. The codivergence theory was investigated further by estimating the time of most recent common ancestor for the SIV lineages that directly gave rise to HIV, found in sooty mangabeys and chimpanzees (Appendix B). The temporal estimates suggest that these SIV lineages are only of hundreds of years old, much younger than expected under the codivergence hypothesis. Next, the same dating techniques were employed to elucidate the evolutionary history of an emerging RNA virus of shrimp, Taura syndrome virus (Appendix C). This analysis provided phylogenetic confirmation that Taura syndrome virus emerged out of the Americas and spread rapidly around the world. Finally, because all of these studies utilized relaxed molecular clocks, a simulation study was performed to test the hypothesis that relaxed molecular clocks provide higher quality phylogenetic inference compared with traditional time-free phylogenetic inference (Appendix D). This simulation found no difference in the overall quality of phylogenetic inference between these methods.

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