Para avaliar se a dinâmica da infecção toxoplásmica em gatos infectados pelo VIF é diferente daquela que ocorre em gatos não infectados por esse retrovírus, gatos adultos infectados pelo Vírus da Imunodeficiência Felina (VIF) clade B assintomáticos (n=7) (Grupo I: VIF+TOXO+), e gatos sem a infecção viral (n=7) (Grupo III: VIF-TOXO+) foram inoculados pela via oral com cistos de Toxoplasma gondii cepa P. Os animais foram avaliados por meio do exame clínico, mensuração de anticorpos IgM e IgG anti-T. gondii pela Reação de Imunofluorescência Indireta, eliminação e quantificação de oocistos pela técnica de flutuação em solução de sacarose, leucograma, e as subpopulações de linfócitos T CD4+ e CD8+ foram mensuradas por meio da citometria de fluxo. Outros dois grupos de gatos, um apenas infectado com o VIF (n=7) (Grupo II: VIF+TOXO-) e outro não infectado com nenhum dos agentes (n=3) (Grupo IV: VIF-TOXO-), constituíram os grupos controle. O período de eliminação de oocistos e a quantidade de oocistos eliminados foram semelhantes entre os Grupos I e III, respectivamente p=1,00 e p=0,201. O período de soroconversão e a duração dos títulos de IgM e IgG também foram semelhantes, respectivamente p=0,535; p=0,789 e p=0,674; p=0,123. No entanto, os episódios febris e de apatia foram mais freqüentes entre os gatos co-infectados (Grupo I) do que entre os animais do grupo não infectado com o vírus (Grupo III), embora estes últimos tenham apresentado diarréia mais freqüente e intensa do que os primeiros. Apenas no grupo co-infectado (Grupo I) um animal desenvolveu uveíte anterior unilateral autolimitante. Exclusivamente no grupo de gatos co-infectados (Grupo I), durante todo o período experimental foi observado aumento do número de leucócitos (p=0,047), linfócitos (p=0,029) e linfócitos T CD8+ (p=0,047) em relação aos gatos do grupo infectado apenas com o T. gondii (Grupo III). O grupo de gatos infectados somente com o VIF (Grupo II) apresentou diminuição quantitativa de linfócitos T CD4+ (p=0,031) em comparação ao grupo controle não infectado com nenhum dos agentes (Grupo IV), evidenciando a ação do vírus em destruir progressivamente essa subpopulação de linfócitos. A relação de linfócitos CD4/CD8 entre os Grupos I e II, infectados pelo VIF, e os Grupos III e IV, não infectados pelo vírus, foi alterada (p<0,001 e p=0,002 respectivamente), observando-se que a infecção toxoplásmica não teve influência sobre esse parâmetro. O aumento dos linfócitos T CD8+ nos gatos co-infectados e a diminuição de linfócitos T CD4+ causada pela infecção pelo VIF podem contribuir para o desenvolvimento de manifestações clínicas mais graves nos gatos infectados por ambos os agentes infecciosos. / Asymptomatic adult cats (n=7) infected with Feline Immunodeficiency Virus (FIV) clade B (Group I: FIV+TOXO+) and normal non-infected cats (n=7) (Group III: FIV-TOXO+) were inoculated, orally with cysts of Toxoplasma gondii strain P, in order to evaluate if there is a difference in dynamics of toxoplasmic infection between cats infected with FIV and naive-FIV cats. The animals were assessed by means of physical exam, T. gondii IgM and IgG antibodies by indirect immunofluorescent reaction, shedding and quantification of oocysts using sugar centrifugation, leucogram and CD4+ and CD8+ T-lymphocytes subsets using cytometry. Others two groups of cats, one of them only infected with FIV (n=7) (Group II: FIV+TOXO-) and other non-infected (n=3) (Group IV: FIV-TOXO-) composed the control groups. The shedding and quantification of oocysts were not different between the Groups I and III, respectively p=1,00 and p=0,201. The serum convertion and the period that during of values of IgM and IgG antibodies were not different, respectively p=0,535; p=0,789 and p=0,674; p=0,123. However, fever and letargy were more frequent between cats co-infected (Group I) than the group not infected with FIV (Group III), although the latter one had presented more frequently intense diarrhea than formers. Just one cat dually infected (Group I) presented autolimitant unilateral anterior uveitis. Only cats co-infected (Group I), during all period of the experiment, presented increase in number of leukocytes (p=0,047), lymphocytes (p=0,029) and CD8+ T lymphocytes subset (p=0,047) comparing to the cats only infected with T. gondii (Group III). Only in the group FIV-infected (Group II) was observed decrease in numbers of CD4+ T lymphocytes subset (p=0,031) compared to the not infected any microrganism (Group IV), showing the virus action to destroy this lymphocyte subset slowly. The CD4/CD8 lymphocyte ratio was different between the Groups I and II, FIV-infected, from Groups III and IV, FIV-naive cats, (p<0,001 e p=0,002 respectively) showing that toxoplasmic infection did not alter this parameter. The increase number of CD8+ T lymphocyte, in dually infected cats, associated with loss of CD4+ T lymphocyte caused by FIV, can contribute for the development of more severe clinical signs in cats dually infected.

The obligate intracellular bacterium, Chlamydia trachomatis, and Herpes Simplex Virus Type-2 (HSV-2) are the leading sexually transmitted pathogens in the world. These infections are usually asymptomatic and clinically mild, but complications can be severe. Reports of dual detection of Chlamydia and HSV within the genital tracts of humans led our laboratory to develop an in vitro Chlamydia/HSV co-infection model. Little is known regarding the specific pathogenesis of Chlamydia and HSV co-infections, but HSV-super-infection of Chlamydia-infected cells caused the chlamydiae to deviate from their normal developmental cycle into a non-replicative state termed persistence, or the chlamydial stress response. Interactions between HSV envelope protein, gD with host cell junction protein, nectin-1, were enough to stimulate the departure from normal chlamydial development. Additional data also suggested that there might be differences between single infection and co-infection outcomes in vivo. Thus, two diverging hypotheses were investigated here: i) that host nectin-1 is required for normal chlamydial development; and ii) that pathogen shedding and/or disease progression in Chlamydia and HSV-2 co-infected animals will differ from that observed in singly-infected animals. Chlamydial infection of nectin-1 knockdown cell lines revealed no inhibition of chlamydial entry, but significant reductions in inclusion size and production of infectious chlamydiae. Additionally, nectin-1 knockout mice shed fewer Chlamydia compared to wild type mice. In other studies, we developed a novel in vivo Chlamydia and HSV-2 intravaginal super-infection model in BALB/c mice. Infection with Chlamydia muridarum, followed up to 9 days later by HSV-2 super-infection, both reduced HSV shedding and protected mice from HSV-induced fatal neurologic disease compared to HSV singly-infected animals. Protection is lost when: i) infected animals are no longer shedding C. muridarum; ii) when mice are inoculated with UV-inactivated C. muridarum; or iii) when viable chlamydiae are eliminated from the genital tract using antibiotics prior to HSV-2 super-infection. Altogether, we have determined that host nectin-1 is required for chlamydial development both in vitro and in vivo, and that chlamydial pre-infection protects mice from subsequent HSV infection. We predict that these observations may lead to novel approaches to prevent human infection by these two common sexually transmitted pathogens.

Das 1995 entdeckte GB-Virus C (GBV-C) gehört als Pegivirus zur Familie der Flaviviridae und ist nichtpathogen. In Industrieländern sind 2 bis 12,5 % der gesunden Bevölkerung und bis zu 45 % der Personen aus Risikokollektiven, z.B. Patienten mit Infektionen mit dem humanen Immundefizienzvirus Typ 1 (HIV-1) oder dem Hepatitis-C-Virus (HCV), virämisch. Die Mehrzahl der klinischen Studien und Metaanalysen zu GBV-C/HIV-1-Koinfektionen zeigten, dass GBV-C mit einem verlangsamten Krankheitsverlauf und einer erhöhten Überlebenswahrscheinlichkeit von GBV-C/HIV-1-koinfizierten Patienten korreliert. In der Hemophilia Growth and Development Study konnte dieser Effekt bei GBV-C/HCV-/HIV-1-infizierten Kindern und Jugendlichen jedoch nur bedingt nachgewiesen werden. Dafür wurde ein Zusammenhang zwischen einer GBV-C/HCV-Koinfektion und dem Ausheilen der HCV-Infektion beobachtet und in einer weiteren Patientenkohorte aus der Anti-D-Studie bestätigt. GBV-C/HCV-koinfizierte Patienten haben schlechtere Chancen, die HCV-Infektion auszuheilen. Der Einfluss von GBV-C auf die HIV-1-Replikation wurde in Zellkulturexperimenten untersucht. Es zeigte sich, dass sich die verschiedenen GBV-C-Isolate hinsichtlich ihrer inhibitorischen Kompetenz unterschieden. Folgende mögliche Ursachen wurden untersucht: 1.) die IRES-Aktivität als Indikator für die Translationseffizienz, 2.) die NS5A-Sequenz des in der Literatur beschriebenen HIV-1-inhibitorisch aktiven 16mer-Peptids sowie 3.) die E2-Sequenz und die HIV-1-inhibitorische Wirkung von 18mer-E2-Peptiden. Es konnten weder Unterschiede in der IRES-Aktivität noch in der NS5A-Sequenz zwischen den unterschiedlich inhibitorisch-kompetenten GBV-C-Isolaten nachgewiesen werden. Im E2-Protein hingegen wurden zwei für alle HIV-1-nichtinhibitorischen GBV-C-Isolate einheitliche Mutationen, E143K/H und T204A, identifiziert. Diese könnten eine Ursache für die Varianz in der Fähigkeit, HIV-1 zu inhibieren, darstellen. Die Mutation an Position E143 ist an der Oberfläche des nativen E2-Proteins exponiert und spielt möglicherweise im Hemmmechanismus eine wichtige Rolle. Hinweise darauf gaben die Untersuchungen mit synthetischen 18mer-Peptiden, von denen das Peptid mit dem größten inhibitorischen Potenzial die Aminosäure an Position 143 beinhaltete. Eine mögliche Theorie des Wirkmechanismus des E2-Proteins wäre wie folgt denkbar: Das E2-Protein interagiert über eine Domäne um die Aminosäure E143 mit dem gp41 des HIV-1, verhindert somit die Fusion von Virus- und Zellmembran und in der Folge den Eintritt des HIV-1 in die Zielzelle.

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-07-23T21:28:41Z No. of bitstreams: 1 Luana Leandro Gois Avaliação da resposta imune celular....pdf: 1029778 bytes, checksum: 6ffe55d1ff3bccef874a467c3f7cec99 (MD5) / Made available in DSpace on 2012-07-23T21:28:41Z (GMT). No. of bitstreams: 1 Luana Leandro Gois Avaliação da resposta imune celular....pdf: 1029778 bytes, checksum: 6ffe55d1ff3bccef874a467c3f7cec99 (MD5) Previous issue date: 2011 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / A Leishmania é considerada um patógeno oportunista em indivíduos infectados pelo HIV. Os mecanismos imunopatogênicos pelos quais o HIV e a Leishmania interagem não estão bem esclarecidos. Assim como, não está definido de que forma a infecção pelo HIV provoca alterações na resposta imune celular específica à Leishmania, o que conduz às apresentações atípicas e disseminadas da leishmaniose descritas nos pacientes coinfectados. O objetivo desta dissertação foi avaliar a resposta imune celular dos pacientes coinfectados por HIV e Leishmania, mais especificamente avaliar a resposta Th1 e perfil das subpopulações de linfócitos T de memória. Para tal, foi avaliada a resposta linfoproliferativa ao antígeno solúvel de Leishmania (SLA) e a proporção das subpopulações de memória central e efetora dos linfócitos T CD4+ específicos para Leishmania por citometria de fluxo. O índice de divisão celular dos linfócitos T CD4+ e CD8+ após o estímulo com SLA dos pacientes coinfectados foi estatisticamente menor em comparação com os pacientes infectados apenas por Leishmania. A resposta proliferativa dos linfócitos T CD4+ ao SLA foi observada em 25 % dos pacientes coinfectados, enquanto que em 12 % dos pacientes coinfectados foi observada proliferação dos linfócitos T CD8+ em resposta ao SLA. Entretanto, em todos os pacientes infectados apenas por Leishmania foi notada a linfoproliferação em resposta ao SLA. As proporções de linfócitos T CD4+ de memória central e efetora específicos para Leishmania foram similares entre os pacientes coinfectados e os pacientes infectados apenas por Leishmania. Entretanto, o número absoluto dos linfócitos T CD4+ de memória central e efetora foi significantemente menor nos pacientes coinfectados em comparação aos pacientes infectados apenas por Leishmania. Os resultados demonstram um prejuízo funcional na imunidade celular específica dos pacientes coinfectados. / The Leishmania is opportunistic pathogens in HIV-1-infected individuals. The immunopathogenic mechanisms by which HIV and Leishmania adversely affect each other are unclear. Furthermore, the impact of HIV-1 on Leishmania-specific cellular immune response leads to atypical and disseminated lesions as described in co-infected patients. The aim of this dissertation is to evaluate the cellular immune response of HIV and Leishmania co-infected patients, specifically to evaluate the profile Th1 and the memory CD4+ T-cell subset. The proliferative response of CD4+ and CD8+ T-cells to soluble Leishmania antigens (SLA) and the frequency memory Leishmania-specific CD4+ T-cell were performed flow cytometry. The median of cell division index of CD4+ and CD8+ T-cells after stimulation with SLA from co-infected patients was significantly lower than in patients infected Leishmania solely. A proliferative response of CD4+ T-cells after stimulation with SLA was observed in 25 % of co-infected patients, while in 12 % of co-infected patients had a proliferative response in the CD8+ T-cells to SLA. In contrast, both CD4+ and CD8+ T-cells subset from all patients infected with Leishmania solely proliferated in response to SLA. The proportion of Leishmania-specific central and effector memory CD4+ T-cells were similar between the coinfected patients and patients infected Leishmania solely. However, the median of absolute number of Leishmania-specific central and effector memory CD4+ T-cells from co-infected patients were significantly lower compared to patients infected Leishmania solely. These results demonstrate the impairment in cellular immune response.

Made available in DSpace on 2016-12-23T13:56:11Z (GMT). No. of bitstreams: 1 Dissertacao de Fabiola Mesquita Callegari.pdf: 683293 bytes, checksum: 63b6076f1043105fa0bedb1cdd6b9ec5 (MD5) Previous issue date: 2011-12-08 / Introdução: A sífilis aumenta o risco de transmitir ou contrair o HIV e pode ter seu curso alterado nestes pacientes. O relato de casos de sífilis entre pacientes que vivem com HIV/AIDS, principalmente entre homens que fazem sexo com homens, tem aumentado na última década. Objetivo: determinar a prevalência de sífilis e fatores associados com a infecção em pacientes HIV/AIDS atendidos no ambulatório de AIDS do Hospital Santa Casa de Misericórdia de Vitória, ES. Metodologia: Estudo transversal conduzido em pacientes HIV/AIDS atendidos entre agosto de 2010 a setembro de 2011. Os pacientes responderam a uma entrevista contendo dados demográficos, comportamentais e clínicos. Amostra de sangue venoso foram realizadas para coleta de VDRL e teste treponêmico (teste rápido) para sífilis. A prevalência de sífilis foi estimada pela presença de teste não treponêmico e teste treponêmico positivos sendo calculado o correspondente intervalo de confiança de 95%. Foram aplicados testes de qui-quadrado com correção de Yates ou de Fischer, e análise multivariada de regressão logística. Resultados: Um total de 438 pacientes foram incluídos no estudo. A média da idade foi 43 (DP 11) anos e da escolaridade 8,1 (DP 4,2) anos de estudo, 55% eram homens e 26,9% eram casados ou tinham parceiros fixos. A prevalência de sífilis foi de 5,3% (IC 95% 3,3% 7,3%). O teste treponêmico foi positivo em 18,9% dos participantes. Na análise multivariada, a sífilis foi associada ao sexo masculino [OR 4,57 IC95% 1,03-20], ser HSH [OR=1,78(IC95% 1,64-4,14)], ao não uso de terapia antiretroviral [OR 0,18 IC95% 0,06-0,59] e a história prévia de sífilis [OR 5,54 IC95% 1,95-15,76]. Conclusão: A co-infecção de sífilis em pacientes que vivem com HIV/AIDS no serviço de atendimento à AIDS foi de 5,3% e esteve associada ao sexo masculino, a ser homen que faz sexo com homem, ao não uso de terapia antiretroviral e história prévia de sífilis. / Backgraound: Syphilis increases the risk of transmitting or contracting HIV and may have change its course in the patients. Reported cases of syphilis among patients living with HIV/AIDS has increased in the last decade, especially among men who have sex with men. Objectives: To determine the prevalence of and factors associated with syphilis infection in HIV/AIDS outpatient clinic at the Santa Casa de Misericórdia de Vitória Hospital, ES. Methods: Cross-sectional study conducted in HIV/AIDS patients treated between August 2010 to September 2011. Patients were interviewed containing demographic , behavioural and clinical signs. Venous blood for VDRL and treponemal test (rapid test) were performed. The prevalence of syphilis was estimated by the presence of positive non-treponemal tests and positive treponemal test and calculated the corresponding confidence interval of 95%. It was applied chi-square test with Yates correction or Fischer and multivariated logistic regression. Results: A total of 438 patients were included in the study. The mean age was (SD 11) years of schooling and 8.1 (SD 4.2) years of study, 55% were men and 26.9% were married or had steady partners. The prevalence of syphilis was 5.3% (CI 95% 3.3% 7.3%). The treponemal test was positive in 18.9% of participants. In multivariated analysis, syphilis was associated with male sex [OR 4,57 CI 95% 1.03-20], being MSM [OR=1,78(IC95% 1,64-4,14)], not using antiretroviral therapy [OR 0,18 CI 95% 0.06-0.59] and previous history of syphilis [OR 5.54 CI 95% 1.95-15.76]. Conclusion: Co-infection of syphilis in patients living HIV/AIDS in customer services to AIDS was 5.3% and was associated with male gender, being men who have sex with men, not use the antiretroviral therapy and previous history of syphilis

Orientador: Mary Marcondes / Banca: Wagner Luís Ferreira / Banca: Raimundo Souza Lopes / Resumo: O objetivo do presente estudo foi determinar em uma população de 302 gatos provenientes de área endêmica para leishmaniose visceral, a prevalência da infecção por Leishmania spp. e a presença de coinfecção pelo Toxoplasma gondii, vírus da imunodeficiência felina (FIV) e vírus da leucemia felina (FeLV). Foram evidenciadas formas amastigotas de Leishmania spp. em 9,93% (30/302) dos animais. A prevalência da leishmaniose observada por meio dos métodos de ELISA-proteína A, ELISA-IgG ou exame parasitológico direto foi de 21,85% (66/302), sendo 13,64% (9/66) positivos no exame parasitológico direto e sororeagentes nas técnicas de ELISA indireto. Doze animais (70,59%) foram sororeagentes para o FIV e a Leishmania spp., enquanto 17 (25,76%) apresentaram anticorpos anti-Toxoplasma gondii e anti-Leishmania spp. e cinco (71,43%) apresentavam infecção pelos três agentes. Não foi observada coinfecção entre Leishmania spp. e o FeLV. Houve associação estatisticamente significante entre a coinfecção por Leishmania spp. e pelo vírus da imunodeficiência felina, bem como entre a presença de Leishmania spp., do vírus da imunodeficiência felina e do Toxoplasma gondii. A sensibilidade e a especificidade dos métodos de ELISA-proteína A, ELISA-IgG e reação de imunofluorescência indireta para o diagnóstico de leishmaniose felina foram de 56,6% e 89,47%, 55,55% e 90,96% e 54,55% e 96,80%, respectivamente. As concordâncias entre a RIFI e as técnicas de ELISA-proteína A e ELISA-IgG foram fracas. No entanto, houve boa concordância entre as duas últimas técnicas. O presente estudo verificou que gatos residentes em área endêmica para leishmaniose visceral são predispostos à coinfecção por Leishmania spp. e vírus da imunodeficiência felina, e que parte deles desenvolvem sintomas inespecíficos e devem ser investigados em um diagnóstico diferencial / Abstract:The aim of this study was to determine, in a population of 302 cats from an endemic area for visceral leishmaniasis, the prevalence of the infection by Leishmania spp. and the presence of co-infection by Toxoplasma gondii, feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV). Amastigote forms of Leishmania spp were evidenced in 9.93% (30/302) of the animals. Prevalence of leishmaniasis by ELISA-prot A, ELISA-IgG or direct parasitological examination was 21.85% (66/302), being 13.64% (9/66) positive in both direct parasitological examination and ELISA. Twelve animals (70.59%) were seroreagent for FIV and Leishmania spp., while 17 (25.76%) showed antibodies against Toxoplasma gondii and Leishmania spp. and five (71.43%) showed antibodies against those three agents. Co-infection was not observed between Leishmania spp. and FeLV. There was statistically significant correlation between the co-infection by Leishmania spp. and by the immunodeficiency virus, as well as among the present of Leishmania spp, feline immunodeficiency virus and Toxoplasma gondii. The susceptibility and the specificities of (the methods) ELISA-prot A, ELISA-IgG and reaction of indirect immunofluorescence for the diagnosis of feline leishmaniasis were 56.6% and 89.47%, 55.55% and 90.96% and 54.55% and 96.80%, respectively. The agreements between RIFI and ELISA-prot A and ELISA-IgG techniques were weak. However, there was a good agreement between the last two techniques. This study verified that cats from endemic areas for visceral leishmaniasis are predisposed to co-infection by Leishmania spp. and feline immunodeficiency virus, and that part of them developed nonspecific symptoms and should be investigated in a differential diagnosis / Mestre

Para avaliar se a dinâmica da infecção toxoplásmica em gatos infectados pelo VIF é diferente daquela que ocorre em gatos não infectados por esse retrovírus, gatos adultos infectados pelo Vírus da Imunodeficiência Felina (VIF) clade B assintomáticos (n=7) (Grupo I: VIF+TOXO+), e gatos sem a infecção viral (n=7) (Grupo III: VIF-TOXO+) foram inoculados pela via oral com cistos de Toxoplasma gondii cepa P. Os animais foram avaliados por meio do exame clínico, mensuração de anticorpos IgM e IgG anti-T. gondii pela Reação de Imunofluorescência Indireta, eliminação e quantificação de oocistos pela técnica de flutuação em solução de sacarose, leucograma, e as subpopulações de linfócitos T CD4+ e CD8+ foram mensuradas por meio da citometria de fluxo. Outros dois grupos de gatos, um apenas infectado com o VIF (n=7) (Grupo II: VIF+TOXO-) e outro não infectado com nenhum dos agentes (n=3) (Grupo IV: VIF-TOXO-), constituíram os grupos controle. O período de eliminação de oocistos e a quantidade de oocistos eliminados foram semelhantes entre os Grupos I e III, respectivamente p=1,00 e p=0,201. O período de soroconversão e a duração dos títulos de IgM e IgG também foram semelhantes, respectivamente p=0,535; p=0,789 e p=0,674; p=0,123. No entanto, os episódios febris e de apatia foram mais freqüentes entre os gatos co-infectados (Grupo I) do que entre os animais do grupo não infectado com o vírus (Grupo III), embora estes últimos tenham apresentado diarréia mais freqüente e intensa do que os primeiros. Apenas no grupo co-infectado (Grupo I) um animal desenvolveu uveíte anterior unilateral autolimitante. Exclusivamente no grupo de gatos co-infectados (Grupo I), durante todo o período experimental foi observado aumento do número de leucócitos (p=0,047), linfócitos (p=0,029) e linfócitos T CD8+ (p=0,047) em relação aos gatos do grupo infectado apenas com o T. gondii (Grupo III). O grupo de gatos infectados somente com o VIF (Grupo II) apresentou diminuição quantitativa de linfócitos T CD4+ (p=0,031) em comparação ao grupo controle não infectado com nenhum dos agentes (Grupo IV), evidenciando a ação do vírus em destruir progressivamente essa subpopulação de linfócitos. A relação de linfócitos CD4/CD8 entre os Grupos I e II, infectados pelo VIF, e os Grupos III e IV, não infectados pelo vírus, foi alterada (p<0,001 e p=0,002 respectivamente), observando-se que a infecção toxoplásmica não teve influência sobre esse parâmetro. O aumento dos linfócitos T CD8+ nos gatos co-infectados e a diminuição de linfócitos T CD4+ causada pela infecção pelo VIF podem contribuir para o desenvolvimento de manifestações clínicas mais graves nos gatos infectados por ambos os agentes infecciosos. / Asymptomatic adult cats (n=7) infected with Feline Immunodeficiency Virus (FIV) clade B (Group I: FIV+TOXO+) and normal non-infected cats (n=7) (Group III: FIV-TOXO+) were inoculated, orally with cysts of Toxoplasma gondii strain P, in order to evaluate if there is a difference in dynamics of toxoplasmic infection between cats infected with FIV and naive-FIV cats. The animals were assessed by means of physical exam, T. gondii IgM and IgG antibodies by indirect immunofluorescent reaction, shedding and quantification of oocysts using sugar centrifugation, leucogram and CD4+ and CD8+ T-lymphocytes subsets using cytometry. Others two groups of cats, one of them only infected with FIV (n=7) (Group II: FIV+TOXO-) and other non-infected (n=3) (Group IV: FIV-TOXO-) composed the control groups. The shedding and quantification of oocysts were not different between the Groups I and III, respectively p=1,00 and p=0,201. The serum convertion and the period that during of values of IgM and IgG antibodies were not different, respectively p=0,535; p=0,789 and p=0,674; p=0,123. However, fever and letargy were more frequent between cats co-infected (Group I) than the group not infected with FIV (Group III), although the latter one had presented more frequently intense diarrhea than formers. Just one cat dually infected (Group I) presented autolimitant unilateral anterior uveitis. Only cats co-infected (Group I), during all period of the experiment, presented increase in number of leukocytes (p=0,047), lymphocytes (p=0,029) and CD8+ T lymphocytes subset (p=0,047) comparing to the cats only infected with T. gondii (Group III). Only in the group FIV-infected (Group II) was observed decrease in numbers of CD4+ T lymphocytes subset (p=0,031) compared to the not infected any microrganism (Group IV), showing the virus action to destroy this lymphocyte subset slowly. The CD4/CD8 lymphocyte ratio was different between the Groups I and II, FIV-infected, from Groups III and IV, FIV-naive cats, (p<0,001 e p=0,002 respectively) showing that toxoplasmic infection did not alter this parameter. The increase number of CD8+ T lymphocyte, in dually infected cats, associated with loss of CD4+ T lymphocyte caused by FIV, can contribute for the development of more severe clinical signs in cats dually infected.

Made available in DSpace on 2015-04-20T12:31:42Z (GMT). No. of bitstreams: 1 PRE-TEXTUAL.pdf: 394027 bytes, checksum: d5e64d94f3ade196d4079ab1173940e8 (MD5) Previous issue date: 2009-06-30 / Fundação de Amparo à Pesquisa do Estado do Amazonas / The global epidemic of AIDS began in 1981, the United States, and after the introduction of antiretroviral drugs to patients infected with HIV / AIDS have been given a higher survival emerged a new challenge, co-infection with the hepatitis C virus (HCV), which is already the leading cause of death in these individuals. The HCV was discovered in 1989 and its main route of transmission, parenteral, is common to HIV, thus increasing the prevalence of co-infection HIV / HCV and are currently more than 30% of those infected by HIV also infected by HCV. There are few studies on co-infection HIV / HCV in the Amazon and this study provides an opportunity to evaluate the association of these viruses. The work is a description of a number of cases and is intended to study the clinical implications and immunobiologicals of co-infection HIV / HCV in a population of patients in the Tropical Medicine Foundation of Amazonas (FMTAM), in the period 2000 to 2007. This study found a prevalence of patients co-infected HIV / HCV of 4.42% (n = 70), with an average annual growth of 3.6%. Of these 72.9% were male, 47.1% were aged 30 | - 40. Of these 80% had completed the first grade, 50% received up to a minimum wage and 55.7% were natural in the city of Manaus where 94.3% from the capital too. Of the patients studied, 68.6% were heterosexuals and 84.3% of patients there was sexual promiscuity as a risk factor. During the study period 34.3% of the patients died. Co-infected individuals, only 25.7% (n = 18/70) to attend the clinic for viral hepatitis FMTAM for collection of biological material. In these patients (n = 18) the mean AST was 61.5 ± 61 U / L, ALT of 62.2 ± 37 U / L and the AST / ALT was 0.88 ± 0.33 U / L. As for lipids 38.9% had total cholesterol> 200mg/dl, 83.3% had HDL ≤ 40 mg / dL, 77.8% had triglycerides> 150 mg / dL and 33.3% had glucose> 110 mg / dL . Included 83.3% of patients used HAART scheme whereby 100% of these were using the protease inhibitor regimen. In applying the FIB-4 score in predicting fibrosis found that 77.8% with a cutoff point was <1.45 and 22.2% with a cutoff> 3.25. As for CD4 + T cells 72.2% had <500 cls/mm3 with a median of 271 cls/mm3, on the T CD8 + 88.9% had ≥ 215 cls/mm3 with a median of 794.5 cls/mm3. The ratio CD4 + / CD8 + was 0.32 cls/mm3. As the viral load of HIV and HCV there was a median of 16,911 copies / mL and 543,209 copies / mL, respectively. In this population 88.9% had the genotype 1 of HCV and 94.4% had a sub-type B HIV. Of these, 83.3% had Child-Pugh A and 61.1% who had normal liver on ultrasound. When the dose cytokines IL4, IL6, IL8, IL10, IL12 and IFN-γ in these patients found that only the IL6 (p = <0.001) showed statistical significance especially when correlated to the logarithm of the HCV viral load (0.031). The results found in this study, despite the low prevalence, have annual growth of co-infection due to improvement in the research of hepatitis C in patients with HIV. These results contribute to a better understanding of the clinical, epidemiological and immunological profile of patients co-infected in the north, because these data may lead to greater understanding of the interaction of these two viruses resulted in early diagnosis and consequent reduction of deaths. / A epidemia mundial da AIDS teve início em 1981, nos Estados Unidos, e pós a introdução dos anti-retrovirais os pacientes infectados com HIV/AIDS passaram a ter uma sobrevida maior surgindo um novo desafio, a co-infecção com o vírus da hepatite C (HCV), a qual já é a principal causa de morte nestes indivíduos. O HCV foi descoberto em 1989 e sua principal via de transmissão, a parenteral, é comum ao HIV, com isso aumentando a prevalência da co-infecção HIV/HCV e estando atualmente, mais de 30% dos infectados pelo HIV também infectados pelo HCV. Existem poucos estudos sobre co-infecção HIV/HCV no Amazonas e o presente estudo oferece uma oportunidade de avaliar a associação destes vírus. O trabalho é do tipo descritivo de uma série de casos e tem o objetivo de estudar as implicações clínicas e imunobiológicas da co-infecção HIV/HCV em uma população de pacientes atendidos na Fundação de Medicina Tropical do Amazonas (FMTAM), no período de 2000 a 2007. Este estudo encontrou uma freqüência de pacientes co-infectados HIV/HCV de 4,4% (n=70), com uma média de crescimento anual de 3,6% dos casos. Destes 72,9% eram do sexo masculino, 47,1% tinham entre 30|- 40 anos. Destes 80% possuíam o primeiro grau completo, 50% recebiam até um salário mínimo e 55,7% eram naturais da cidade de Manaus sendo que 94,3% também procedentes da capital. Dos pacientes estudados, 68,6% eram heterossexuais e em 84,3% dos pacientes encontrou-se a promiscuidade sexual como fator de risco. No período do estudo 34,3% dos pacientes foram à óbito. Dos indivíduos co-infectados, apenas 25,7% (n=18/70) comparecerem ao ambulatório de hepatites virais da FMTAM para coleta de material biológico. Nestes pacientes (n=18) a média da AST foi 61,5±61 U/L, da ALT 62,2±37 U/L e a relação AST/ALT foi 0,88±0,33 U/L. Quanto aos lipídeos 38,9% apresentaram colesterol total >200mg/dL, 83,3% apresentaram HDL ≤ 40 mg/dL, 77,8% tinham triglicerídeos >150 mg/dL e 33,3% tinham glicemia >110 mg/dL. Dos pacientes incluídos 83,3% usavam esquema HAART sendo que 100% destes faziam uso de inibidor da protease no esquema. Ao aplicar o escore FIB-4 para predizer fibrose verificou-se que 77,8% ficou com ponto de corte <1,45 e 22,2% com ponto de corte >3,25. Quanto às células T CD4+ 72,2% tinham <500 cls/mm3 com uma mediana de 271 cls/mm3, quanto ao T CD8+ 88,9% tinham ≥215 cls/mm3 com uma mediana de 794,5 cls/mm3. A razão CD4+ /CD8+ foi 0,32 cls/mm3. Quanto à carga viral do HIV e do HCV verificou-se uma mediana de 16.911 cópias /mL e de 543.209 cópias/mL, respectivamente. Nesta população 88,9% apresentaram o genótipo 1 do HCV e 94,4% apresentaram o sub-tipo B do HIV. Destes, 83,3% apresentavam Child-Pugh A sendo que 61,1% apresentavam fígado normal na ultra-sonografia. Ao dosar as citocinas IL4, IL6, IL8, IL10, IL12 e IFN-γ nestes pacientes verificou-se que apenas a IL6 (p= <0,001) apresentou significância estatística principalmente quando correlacionada ao logaritmo da carga viral do HCV (0,031). Os resultados encontrados neste estudo, apesar da baixa prevalência, apresentam crescimento anual da co-infecção provavelmente devido à melhora na investigação da hepatite C nos pacientes com HIV. Estes resultados contribuem para um melhor conhecimento sobre os dados clínicos, epidemiológicos, bem como perfil imunológico dos pacientes co-infectados da região Norte, uma vez que estes dados podem levar à uma maior compreensão da interação destes dois vírus resultando em diagnóstico precoce, e conseqüente redução dos óbitos.

Philosophiae Doctor - PhD / The global impact of the converging dual epidemics of tuberculosis (TB) and human immunodeficiency virus (HIV) is one of the major public health challenges of our time, because in many countries, human immunodeficiency virus (HIV) and mycobacterium tuberculosis (TB) are among the leading causes of morbidity and mortality. It is found that infection with HIV increases the risk of reactivating latent TB infection, and HIV-infected individuals who acquire new TB infections have high rates of disease progression. Research has shown that these two diseases are enormous public health burden, and unfortunately, not much has been done in terms of modeling the dynamics of HIV-TB co-infection at a population level. In this thesis, we study these models and design and analyze robust numerical methods to solve them. To proceed in this direction, first we study the sub-models and then the full model. The first sub-model describes the transmission dynamics of HIV that accounts for behavior change. The impact of HIV educational campaigns is also studied. Further, we explore the effects of behavior change and different responses of individuals to educational campaigns in a situation where individuals may not react immediately to these campaigns. This is done by considering a distributed time delay in the HIV sub-model. This leads to Hopf bifurcations around the endemic equilibria of the model. These bifurcations correspond to the existence of periodic solutions that oscillate around the equilibria at given thresholds. Further, we show how the delay can result in more HIV infections causing more increase in the HIV prevalence. Part of this study is then extended to study a co-infection model of HIV-TB. A thorough bifurcation analysis is carried out for this model. Robust numerical methods are then designed and analyzed for these models. Comparative numerical results are also provided for each model. / South Africa

Interaction of Herpes Simplex Virus (HSV) glycoprotein D (gD) with the host cell surface during Chlamydia trachomatis/HSV co-infection stimulates chlamydiae to become persistent. During viral entry, gD interacts with one of 4 host co-receptors: HVEM (herpes virus entry mediator), nectin-1, nectin-2 and 3-O-sulfated heparan sulfate. HVEM and nectin-1 are high-affinity entry receptors for both HSV-1 and HSV-2. Nectin-2 mediates HSV-2 entry but is inactive for HSV-1, while 3-O-sulfated heparan sulfate facilitates HSV-1, but not HSV-2, entry. Western blot and RT-PCR analyses demonstrate that HeLa and HEC-1B cells express nectin-1 and nectin-2, but not HVEM. Because both HSV-1 and HSV-2 trigger persistence, these data suggest that nectin-1 is the most likely co-receptor involved. Co-infections with nectin-1 specific HSV-1 mutants stimulate chlamydial persistence, as evidenced by aberrant body (AB) formation and decreased production of elementary bodies (EBs). These data indicate that nectin-1 is involved in viral-induced chlamydial persistence. However, inhibition of signal transduction molecules associated with HSV attachment and entry does not rescue EB production during C. trachomatis/HSV-2 co-infection. HSV attachment also does not activate Cdc42 in HeLa cells, as would be expected with viral stimulated activation of nectin-1 signaling. Additionally, immunofluorescence assays confirm that HSV infection decreases nectin-1 expression. Together, these observations suggest that gD binding-induced loss of nectin-1 signaling negatively influences chlamydial growth. Chlamydial infection studies in nectin-1 knockdown (NKD) HeLa cell lines support this hypothesis. In NKD cells, chlamydial inclusions are smaller in size, contain ABs, and produce significantly fewer infectious EBs compared to C. trachomatis infection in control HeLa cells. Overall, the current study indicates that the actions of host molecule, nectin-1, are required for successful C. trachomatis development.