Thesis (M.S.P.H.)--University of Michigan, 1939.

Thesis (M.S.P.H.)--University of Michigan, 1939.

No description available.

Two-dimensional electrophoretic protein profiles of in vivo and in vitro propagated T.pallidum subsps. pallidum Nichols strain were analyzed and compared. This comparative analysis revealed two in vitro synthesized, cytoplasmic cylinder-associated polypeptides with molecular masses 29.5 and 34.7 kDa, pI 5.62, and one in vitro "lost" polypeptide with molecular mass 34.7 kDa, pI 5.34. integral membrane proteins of in vitro and in vivo propagated T. pallidum was identified by phase partitioning with the nonionic Triton X-114, and twelve outer membrane-associated, antigenic proteins were identified in western blots probed with pooled human secondary syphilitic sera. The solubilization of the outer membrane of T. pallidum with Triton X-114 were monitored by electron microscopy. Treatment of freshly harvested 35S labeled T. pallidum with 1% Triton X-114 resulted in solubilization of the outer membrane and reduction of the diameter of the treponemes from .14 +/- .02 micrometers to .095 +/- .003 micrometers. Examination of thin sections of untreated organisms showed integrity of outer and cytoplasmic membranes. In contrast, thin sections of Triton X-114-treated trponemes showed integrity of the cytoplasmic membrane but the loss of the outer membrane. The cytoplasmic cylinders generated by detergent treatment retained their periplasmic flagella, as judged by electron microscopy and immunoblotting. Integral membrane proteins of Treponema phagedenis were also identified by phase partitioning with Triton X-114, and sizteen cross-reactive, outer membrane-associated, outer membrane-associated, antigenic polypeptides were identified in western blots probed with pooled human secondary syphilitic sera. The results of this study indicate that tow-dimensional protein profiles of in vivo and in vitro propagated T.pallidum are almost identical except for the differences mentioned. This results also indicate that 1% Triton X-114 selectively solubilizes the outer membrane, and the antigenic hydrophobic proteins present in the detergent phrase are located exclusively in the outer membrane.

Treponema pallidum ssp. pallidum is the causative agent of syphilis, a multi-stage bacterial infection, transmitted sexually or from mother-to-child, with an unparalleled range of symptoms arising from the ability of treponemes to penetrate any tissue and cross immune privileged endothelial barriers to access the brain, the eye, and the fetus. Further, without treatment T. pallidum evades immune clearance and persists within the host to establish a chronic infection. These characteristics suggest that T. pallidum may have evolved unique mechanisms for immune escape and to mediate host-cell interactions. The findings presented in this dissertation contribute to our knowledge of T. pallidum pathogenesis by investigating a previously unexplored host-cell interaction, between T. pallidum and human platelets. These results validate the hypothesis that, as a pathogen which successfully utilizes vascular dissemination, T. pallidum would not only encounter, but interact with human platelets, complex cells now viewed as vascular sentinels that participate in many host-pathogen interactions. This is the first study to demonstrate that T. pallidum interacts with human platelets and to characterize and quantify these interactions using high resolution microscope imaging techniques (video and frame analysis). These interactions were shown to be complex, reversible and mediated by motile treponemes localizing to stationary, (slide-adhered) activated platelets, versus to free-floating, inactive platelets. In addition, it was found that T. pallidum discriminates between the level of platelet activation and preferentially localized to the most activated platelet. Treponema pallidum was also able to induce platelet activation following an extended lag period. Modified chemotaxis assays quantified by flow cytometry, were used to investigate the migration of T. pallidum in response to the plasma of platelets differentially activated with infection-relevant host components (thrombin, collagen). The results herein reveal that T. pallidum discriminates between different mechanisms of platelet activation, with a significant preference towards the secretions of collagen-activated platelets (under these experimental conditions), compared with that of inactive or thrombin-activated platelets. Previously, T. pallidum chemotaxis had been investigated through genomic characterization and molecular interaction studies with recombinant proteins. This investigation is the first time live T. pallidum was utilized for in vitro chemotaxis assays and is also the first study of pathogen chemotaxis in response to the secretions of differentially activated platelets. The body of work in this dissertation provides a foundation to further investigate the role of T. pallidum-platelet interactions during infection, adding a new host-cell interaction to our understanding of T. pallidum pathogenesis. The evidence that the molecular gradients of host components can affect T. pallidum migration suggests an important role for chemotaxis during T. pallidum infection. Together, the characterization of platelet-interactions and treponeme chemotaxis in response to host components, adds to our knowledge of T. pallidum-host interactions, and eludes to additional pathogenic strategies that may facilitate T. pallidum dissemination and immune evasion. / Graduate / 2022-01-14

No description available.

Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2019-01-25T14:31:54Z No. of bitstreams: 2 Dissertação - Elisângela Franciscon Naves - 2018.pdf: 4013641 bytes, checksum: fcb8f472c325bd54638ccd6b1ef20093 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2019-01-28T10:49:36Z (GMT) No. of bitstreams: 2 Dissertação - Elisângela Franciscon Naves - 2018.pdf: 4013641 bytes, checksum: fcb8f472c325bd54638ccd6b1ef20093 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2019-01-28T10:49:36Z (GMT). No. of bitstreams: 2 Dissertação - Elisângela Franciscon Naves - 2018.pdf: 4013641 bytes, checksum: fcb8f472c325bd54638ccd6b1ef20093 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-12-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Individuals deprived of their liberty are at high risk for syphilis, due to sexual and non-sexual risk behaviors, such as inconsistent condom use, sex for money and / or drugs, and multiple sexual partnerships. The objective of this study was to investigate the seroprevalence of syphilis infection in deprived men in the southern region of Goiás. Between September 2017 and May 2018, a cross-sectional study was conducted on 194 men deprived of liberty from a regional prison south of the state of Goiás. All participants were interviewed about socio-demographic characteristics, sexual and non-sexual risk behaviors for syphilis. Next, blood samples were collected for the detection of anti-T. pallidum antibodies by immunochromatographic treponemal test (rapid test). Positive samples were retested by the Venereal Disease Research Laboratory / VDRL. Active syphilis was considered positive in the rapid test and titers of VDRL ≥ 1: 8. Of the 194 samples tested by immunochromatographic examination, 11.8% (95% CI: 7.8-17.3%) were positive and 7.7% (95% CI: 4.7-12.5%) presented VDRL ≥ 1: 8. The prevalence of exposure to Treponema pallidum was 23 times higher than that estimated in Brazilian conscripts (95% CI: 0.45-0.61) and 8 times higher than that found in blood donors from São Paulo (95% CI: 1.31 -1.36). In multiple regression analysis, the prevalence of exposure to T. pallidum was 36% (RPaj: 0.39; 95% CI: 0.18-0.86) in individuals who reported sexual relations with sex workers when compared to those who did not have this characteristic. In addition, it was observed that the prevalence of active syphilis increased with increasing prison time (RPaj: 1.02, 95% CI: 1.00-1.08, p-value = 0.030). The results of this investigation show a high prevalence of syphilis in the men deprived of liberty investigated and indicate the need to implement strategies for prevention and control of infection in such individuals, including educational health actions, rapid and efficient diagnosis and appropriate treatment of cases of active syphilis. / Indivíduos privados de liberdade apresentam elevado risco para sífilis, devido aos comportamentos de risco sexuais e não sexuais, como uso inconsistente do preservativo, troca de sexo por dinheiro e/ou drogas e múltiplas parcerias sexuais. O objetivo desse estudo foi investigar a soroprevalência da infecção por sífilis em homens privados de liberdade, região sul de Goiás. Entre setembro de 2017 a maio de 2018, um estudo de corte transversal foi conduzido em 194 homens privados de liberdade de um presidio regional do sul do estado de Goiás. Todos os participantes foram entrevistados sobre características sociodemograficas, comportamentos sexuais e não sexuais de risco para sífilis. A seguir, foram coletadas amostras de sangue para detecção de anticorpos anti- T. pallidum através do teste treponêmico imunocromatográfico (teste rápido). As amostras positivas foram retestadas pelo Venereal Disease Research Laboratory/Laboratório de Pesquisa de Doenças Venéreas (VDRL). Considerou-se sífilis ativa positividade no teste rápido e títulos de VDRL ≥ 1:8. Das 194 amostras testadas pelo exame imunocromatográfico, 11,8% (IC 95%: 7,8-17,3%) foram positivas e 7,7% (IC 95%: 4,7-12,5%) apresentaram títulos de VDRL ≥ 1:8. A prevalência de exposição ao Treponema pallidum foi 23 vezes superior à estimada em conscritos brasileiros (IC 95%: 0,45-0,61) e 8 vezes maior ao encontrado em doadores de sangue de São Paulo (IC 95%: 1,31-1,36). Em análise de regressão múltipla, a prevalência de exposição ao T. pallidum foi 36% (RPaj: 0,39; IC 95%: 0,18-0,86) em indivíduos que relataram relações sexuais com profissionais do sexo quando comparado aqueles que não apresentavam essa característica. Além disso, observou-se que a prevalência da sífilis ativa aumentou com o aumento do tempo de prisão (RPaj:1,02; IC 95%: 1,00-1,08; p-valor= 0,030). Os resultados dessa investigação evidenciam elevada prevalência de sífilis nos homens privados de liberdade investigados e indicam a necessidade de implementação de estratégias de prevenção e controle da infecção em tais indivíduos, incluindo ações educativas em saúde, diagnóstico rápido e eficiente além do tratamento adequado dos casos de sífilis ativa.

O diagnóstico de neurosífilis é freqüentemente dependente dos resultados dos testes serológicos e alterações no líquido cefalorraquidiano, mas a confiabilidade desses resultados em pacientes com infecção pelo HIV-1 tem sido questionada especialmente em pacientes assintomáticos com sífilis latente. O estudo se propõe avaliar a presença de DNA do T. pallidum no LCR de pacientes assintomáticos infectados pelo HIV, com o diagnóstico de sífilis. Amostras de LCR foram coletadas de 12 pacientes infectados pelo HIV atendidos em um terciário localizado no sul do Brasil , durante o período de 2012 a 2013. A presença de DNA do T. pallidum foram analisadas nas amostras de LCR pelo método de PCR “seminested”. Dados demográficos dos pacientes, parâmetros bioquímicos, celularidade e VDRL do LCR e linfócitos T-CD4 também foram analisados. Nas amostras de LCR de cinco dos 12 pacientes (40%) foram detectados o DNA do T. pallidum . Inesperadamente, nestes doentes, os níveis de contagem de células, proteína e glicose no LCR foram normais. Além disso , nenhuma destas cinco amostras de CSF apresentou uma reacção positiva VDRL. Os títulos de VDRL no soro foram semelhantes entre pacientes positivos e negativos para a presença T. pallidum DNA no LCR. A maioria dos pacientes com DNA de T. pallidum detectável apresentaram baixos títulos de VDRL no soro. O VDRL sérico elevado com título de 1:64 foi observada em apenas um paciente. Nossos resultados demostraram que os pacientes assintomáticos infectados pelo HIV com evidência de sífilis latente e LCR normais podem apresentar DNA de T. pallidum detectável no LCR. A detecção do DNA do T. pallidum pelo nosso seminested PCR pode fornecer informações adicionais além da análise convencional do LCR para o diagnóstico de neurossífilis. presença do DNA de T. pallidum no LCR em pacientes infectados pelo HIV com sífilis latente e resultados de LCR normais pode determinar uma mudança terapêutica do uso de penicilana benzatina intramuscular para o de penicilina cristalina intravenosa aquosa para o tratamento da sífilis. / Neurosyphilis diagnosis is frequently dependent upon the results of serological tests and cerebrospinal fluid abnormalities, but the reliability of findings in patients with HIV-1 infection has been questioned, especially asymptomatic patients with latent syphilis, We present the data on the presence of T. pallidum DNA in CSF from asymptomatic HIV-infected patients with the diagnosis of syphilis. CSF and serum samples were collected from 12 HIV-infected patients attending a tertiary care located in southern Brazil, during the period 2012 to 2013. In CSF samples from five of 12 patients (40%), we detected T. pallidum DNA. Unexpectedly, in these patients, CSF cell count, protein and glucose levels were normal. In addition, none of these 5 CSF samples presented a positive VDRL reaction. Serum VDRL titers were similar between patients with positive and negative CSF T. pallidum DNA. Most patients with detectable T. pallidum DNA presented low serum VDRL titers. Serum VDRL titer of 1:64 was observed in one patient. Our results have shown that asymptomatic HIV-infected patients with evidence of latent syphilis and normal CSF might present detectable T. pallidum DNA in the CSF. The detection of T. pallidum DNA by our seminested PCR provide additional information beyond conventional CSF analysis for diagnosis of neurosyphilis. The detection of T. pallidum DNA in the CSF despite normal CSF findings in HIV-infected patients could also provide a different therapeutic approach including the use of intravenous aqueous crystalline penicillin.

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 147-179).

O diagnóstico de neurosífilis é freqüentemente dependente dos resultados dos testes serológicos e alterações no líquido cefalorraquidiano, mas a confiabilidade desses resultados em pacientes com infecção pelo HIV-1 tem sido questionada especialmente em pacientes assintomáticos com sífilis latente. O estudo se propõe avaliar a presença de DNA do T. pallidum no LCR de pacientes assintomáticos infectados pelo HIV, com o diagnóstico de sífilis. Amostras de LCR foram coletadas de 12 pacientes infectados pelo HIV atendidos em um terciário localizado no sul do Brasil , durante o período de 2012 a 2013. A presença de DNA do T. pallidum foram analisadas nas amostras de LCR pelo método de PCR “seminested”. Dados demográficos dos pacientes, parâmetros bioquímicos, celularidade e VDRL do LCR e linfócitos T-CD4 também foram analisados. Nas amostras de LCR de cinco dos 12 pacientes (40%) foram detectados o DNA do T. pallidum . Inesperadamente, nestes doentes, os níveis de contagem de células, proteína e glicose no LCR foram normais. Além disso , nenhuma destas cinco amostras de CSF apresentou uma reacção positiva VDRL. Os títulos de VDRL no soro foram semelhantes entre pacientes positivos e negativos para a presença T. pallidum DNA no LCR. A maioria dos pacientes com DNA de T. pallidum detectável apresentaram baixos títulos de VDRL no soro. O VDRL sérico elevado com título de 1:64 foi observada em apenas um paciente. Nossos resultados demostraram que os pacientes assintomáticos infectados pelo HIV com evidência de sífilis latente e LCR normais podem apresentar DNA de T. pallidum detectável no LCR. A detecção do DNA do T. pallidum pelo nosso seminested PCR pode fornecer informações adicionais além da análise convencional do LCR para o diagnóstico de neurossífilis. presença do DNA de T. pallidum no LCR em pacientes infectados pelo HIV com sífilis latente e resultados de LCR normais pode determinar uma mudança terapêutica do uso de penicilana benzatina intramuscular para o de penicilina cristalina intravenosa aquosa para o tratamento da sífilis. / Neurosyphilis diagnosis is frequently dependent upon the results of serological tests and cerebrospinal fluid abnormalities, but the reliability of findings in patients with HIV-1 infection has been questioned, especially asymptomatic patients with latent syphilis, We present the data on the presence of T. pallidum DNA in CSF from asymptomatic HIV-infected patients with the diagnosis of syphilis. CSF and serum samples were collected from 12 HIV-infected patients attending a tertiary care located in southern Brazil, during the period 2012 to 2013. In CSF samples from five of 12 patients (40%), we detected T. pallidum DNA. Unexpectedly, in these patients, CSF cell count, protein and glucose levels were normal. In addition, none of these 5 CSF samples presented a positive VDRL reaction. Serum VDRL titers were similar between patients with positive and negative CSF T. pallidum DNA. Most patients with detectable T. pallidum DNA presented low serum VDRL titers. Serum VDRL titer of 1:64 was observed in one patient. Our results have shown that asymptomatic HIV-infected patients with evidence of latent syphilis and normal CSF might present detectable T. pallidum DNA in the CSF. The detection of T. pallidum DNA by our seminested PCR provide additional information beyond conventional CSF analysis for diagnosis of neurosyphilis. The detection of T. pallidum DNA in the CSF despite normal CSF findings in HIV-infected patients could also provide a different therapeutic approach including the use of intravenous aqueous crystalline penicillin.