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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.
41

Evaluating the Presumptive Treatment Gap and Effectiveness of Patient Delivered Partner Therapy for Preventing Chlamydia trachomatis Reinfection

Nemeth, Sheila Mrunal Vaidya January 2017 (has links)
Expedited partner therapy (EPT) is a strategy for treating the partners of chlamydia index cases by which a health care provider gives an index patient drugs or a prescription for treatment of chlamydia to deliver to their sex partner without an intervening medical evaluation of the partner. Despite routine offer of EPT in New York City Department of Health and Mental Hygiene (DOHMH) sexual health clinics, the majority of patients who are eligible for EPT do not receive it, largely because EPT eligibility requires lab confirmation of chlamydial infection, which is lacking in situations where patients are treated for chlamydia on the same day they are tested for chlamydia (i.e., presumptive treatment). These patients become eligible for EPT after they leave the clinic and often do not return for EPT. This dissertation includes three papers: one systematic review and two original analyses. The objective of the systematic review was to synthesize existing estimates of EPT effectiveness to better understand the impact of biases on these estimates; a meta-analysis provided an aggregate estimate of the effectiveness of EPT for preventing index patient reinfection with chlamydia and/or gonorrhea. We found 6 studies that included some measure of EPT effectiveness. Meta-analysis revealed that EPT significantly reduced the risk of reinfection from chlamydia and/or gonorrhea, but it also revealed a substantial amount of heterogeneity. Systematic review revealed that inclusion of patients whose sex partners were at the clinic or already treated for infection was a common source of bias among existing estimates of EPT effectiveness. The two original analyses used data from NYC DOHMH sexual health clinics where EPT is routinely offered as patient delivered partner therapy (PDPT), a form of EPT where medication is given directly to the index patient. The objective of the first analysis was to identify predictors of presumptive treatment and predictors of being offered PDPT among patients eligible for PDPT in the NYC clinics. This analysis demonstrated that patient diagnosis as a contact to a sexually transmitted infection (STI) that would warrant treatment with azithromycin or doxycycline (termed STI contacts) was the best predictor of presumptive treatment in NYC DOHMH sexual health clinics. Patients who were not contacts to such STIs or who were STI contacts with more than one sex partner were more likely to be offered PDPT compared to patients who were STI contacts and reported ≤ 1 sex partner. Males not diagnosed as STI contacts were identified as a target population for increasing rates of PDPT offer. The objective of the last analysis was to provide an estimate of PDPT effectiveness for preventing index patient reinfection with chlamydia. This analysis was novel compared to existing estimates of EPT effectiveness in that we excluded patients whose sex partners were at the clinics at the time of chlamydia testing, treatment, or PDPT offer. We found that PDPT significantly reduced the risk of repeat chlamydial infection at both 6 months and 1 year after initial infection. This result was unchanged by multiple sensitivity analyses that assessed the validity of our estimate. In this dissertation, we were able to fill gaps in the literature regarding EPT implementation. The results may help to decrease missed opportunities for offering patients EPT and to support the continued scale-up and optimization of EPT.
42

Analysis of chlamydial and host proteins associated with infection /

Chu, Hencelyn G. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.
43

Gymnasieungdomars kunskap samt uppfattning om Chlamydia trachomatis / Upper secondary school youths knowledge and understanding about Chlamydia trachomatis

Matic, Nina, Matsson, Kristina January 2008 (has links)
Ungdomar genomgår en mognadsprocess innehållande ett flertal viktiga faktorer i dagens samhälle. Utvecklingen består av att bli självständig, forma personligheten, hantera känslor samt hantera sexualitet. I detta ingår att skydda sig mot den sexuellt överförbara infektionen Chlamydia trachomatis (CT). Syftet med studien var att beskriva gymnasieungdomars uppfattning om infektionen. Hur är kunskapen i ämnet? På vilket sätt tror de att ungdomar skyddar sig? Hur ser de på kärlek och sexualitet? Författarna har valt en kvalitativ ansats med fokusgrupps intervjuer och analyserat resultatet enligt innehållsanalys. Fyra intervjuer har utförts där två flickgrupper respektive två pojkgrupper medverkat. Fyra teman förekommer i resultatet; Uppfattning och kunskap kring att drabbas av CT, uppfattning om sex och kärlek, attityder till skydd samt sexualundervisning. Resultatet visar likheter och skillnader hos flickor och pojkar i författarnas intervjuer. Kunskap om CT varierar, men att konsekvensen av en obehandlad CT kan leda till infertilitet hade samtliga ungdomar kunskap om. Även psykologiska aspekter framkommer. Resultatet speglar skillnader gällande sex och kärlek. Det första samlaget är en ”milstolpe” enligt pojkarna medan flickor anser att det hör ihop. Skydd förknippas med ”lathet” och skydd mot oönskad graviditet, inte skydd mot CT. / Youths are going through a growing process involving many different factors.  The development consists of becoming independent, shape personality, handle feelings and sexuality.  This includes protecting yourself against the sexually transmitted disease, Chlamydia trachomatis (CT). The purpose of this study was to describe upper secondary school youths knowledge and understanding of the infection. How is the knowledge in the subject? In what way do they think youths protect themselves? What are their views about love and sexuality? The authors have chosen a qualitative approach with interviews in focus groups. The data was analyzed with content analyse. Four interviews have been done, where two groups of girls and two groups of boys participated. Four themes exist in the results; knowledge and understanding of CT, understanding of sex and love, attitudes towards protection and sexual education. The result shows similarities and differences between boys and girls in the interviews. The knowledge about CT fluctuates, but the knowledge about that a not treated CT can give rise to infertility did the group knowledge about. Even psychological aspects appear. The result reflects differences about sex and love. The first intercourse is a "milestone" according to the boys whereas the girls have the opinion that it belongs together. Protection is put together with "laziness" and unplanned pregnancy, not protection against CT.
44

Gymnasieungdomars kunskap samt uppfattning om Chlamydia trachomatis / Upper secondary school youths knowledge and understanding about Chlamydia trachomatis

Matic, Nina, Matsson, Kristina January 2008 (has links)
<p>Ungdomar genomgår en mognadsprocess innehållande ett flertal viktiga faktorer i dagens samhälle. Utvecklingen består av att bli självständig, forma personligheten, hantera känslor samt hantera sexualitet. I detta ingår att skydda sig mot den sexuellt överförbara infektionen Chlamydia trachomatis (CT). Syftet med studien var att beskriva gymnasieungdomars uppfattning om infektionen. Hur är kunskapen i ämnet? På vilket sätt tror de att ungdomar skyddar sig? Hur ser de på kärlek och sexualitet? Författarna har valt en kvalitativ ansats med fokusgrupps intervjuer och analyserat resultatet enligt innehållsanalys. Fyra intervjuer har utförts där två flickgrupper respektive två pojkgrupper medverkat. Fyra teman förekommer i resultatet; Uppfattning och kunskap kring att drabbas av CT, uppfattning om sex och kärlek, attityder till skydd samt sexualundervisning. Resultatet visar likheter och skillnader hos flickor och pojkar i författarnas intervjuer. Kunskap om CT varierar, men att konsekvensen av en obehandlad CT kan leda till infertilitet hade samtliga ungdomar kunskap om. Även psykologiska aspekter framkommer. Resultatet speglar skillnader gällande sex och kärlek. Det första samlaget är en ”milstolpe” enligt pojkarna medan flickor anser att det hör ihop. Skydd förknippas med ”lathet” och skydd mot oönskad graviditet, inte skydd mot CT.</p> / <p> </p><p>Youths are going through a growing process involving many different factors.  The development consists of becoming independent, shape personality, handle feelings and sexuality.  This includes protecting yourself against the sexually transmitted disease, Chlamydia trachomatis (CT). The purpose of this study was to describe upper secondary school youths knowledge and understanding of the infection. How is the knowledge in the subject? In what way do they think youths protect themselves? What are their views about love and sexuality? The authors have chosen a qualitative approach with interviews in focus groups. The data was analyzed with content analyse. Four interviews have been done, where two groups of girls and two groups of boys participated. Four themes exist in the results; knowledge and understanding of CT, understanding of sex and love, attitudes towards protection and sexual education. The result shows similarities and differences between boys and girls in the interviews. The knowledge about CT fluctuates, but the knowledge about that a not treated CT can give rise to infertility did the group knowledge about. Even psychological aspects appear. The result reflects differences about sex and love. The first intercourse is a "milestone" according to the boys whereas the girls have the opinion that it belongs together. Protection is put together with "laziness" and unplanned pregnancy, not protection against CT.</p>
45

Custo-efetividade do rastreamento da infecção por Chlamydia trachomatis em mulheres brasileiras / Cost-effectiveness of Chlamydia trachomatis screening in Brazilian women

Andrade, Elisa Tomazzini, 1980- 19 August 2018 (has links)
Orientador: Paulo César Giraldo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T17:07:18Z (GMT). No. of bitstreams: 1 Andrade_ElisaTomazzini_M.pdf: 2783793 bytes, checksum: 73e44a9ff1fd74358814f080307a0b58 (MD5) Previous issue date: 2012 / Resumo: Introdução: A importância da infecção por Chlamydia trachomatis não está relacionada apenas à sua elevada frequência, mas principalmente pelas graves repercussões no aparelho genital feminino. Apenas 30% das pacientes infectadas apresentam sintomas e só 40% terão sinais que possam evidenciar sua presença. Cerca de 70% dos casos de infecção por Chlamydia trachomatis são assintomáticos e acabam não sendo diagnosticados, havendo, portanto a necessidade de programa de rastreamento para diagnóstico e tratamentos precoces, o qual não existe no Brasil. Objetivo: Avaliar custo-efetividade do rastreamento por biologia molecular (captura híbrida) para Chlamydia trachomatis em mulheres brasileiras sexualmente ativas. Desenho do estudo: Estudo de custo-efetividade. A decisão de rastrear Chlamydia trachomatis foi estruturada a partir de uma coorte hipotética de 10.000 mulheres sexualmente ativas com idade entre 15 e 25 anos. O horizonte de tempo trabalhado no modelo de Markov foi de 10 anos e foi realizada a análise de prevalência e probabilidades de transição interestados de saúde a partir de revisão de dados já publicados obtidos nas bases de dados Medline, Embase, LILACS, Cochrane Controlled Trial Register. Resultados: A simulação do rastreamento da infecção por Chlamydia trachomatis por biologia molecular (Captura Híbrida) em população geral entre 15 e 25 anos, acarreta a redução de 2.072 casos de sequelas (Dor Pélvica Crônica, Gravidez Ectópica e Infertilidade de causa tubária) em 10.000 mulheres, ao custo de R$917,00 por caso de sequela evitado. Conclusão: A análise demonstrou uma boa relação de custo-efetividade considerando a estratégia de evitar sequelas de infecção por Chlamydia trachomatis não diagnosticada clinicamente e tratada através de rastreamento por biologia molecular / Abstract: Introduction: The importance of Chlamydia trachomatis is not only related to its high frequency, but mainly to the severe repercussion on the female reproductive system. Only 30% of infected patients presented symptoms and only 40% will have a sign that could show its presence. About 70% of these cases are asymptomatic and will be not diagnosed, so there is a need for a specific program that will track patients at the time of diagnosis and their early treatment period. It is clear that this program does not exist in Brazil. Objective: To evaluate the cost effectiveness of tracking Chlamydia trachomatis on sexually active women through a simulation of a tracking program that could be applied to the Brazilian population. Study design: Cost effectiveness study. The decision of tracking Chlamydia trachomatis was structured by a hypothetical cohort of 10.000 sexually active women aged up to 25 years. The working time horizon was 10 years on the Markov model and the prevalence analysis was made with the data revision of already published data (secondary data analysis) obtained on databases, using web sites such as Medline, Embase, LILACS, Cochrane Controlled Trial Register. Results: The simulation of Chlamydia trachomatis screening by molecular biology (Hybrid Capture) in the general population aged between 15 and 25 causes a reduction of 2,072 cases of sequelae (chronic pelvic pain, ectopic pregnancy and tubal infertility cause) in 10,000 women, at a cost of R$917.00 per case of sequelae. Conclusion: The analysis shows the strategy of avoiding sequelae of Chlamydia trachomatis using molecular biology to screen the population at risk to be cost-effective / Mestrado / Fisiopatologia Ginecológica / Mestre em Ciências da Saúde
46

Serological studies on <em>Chlamydia pneumoniae</em> infections

Paldanius, M. (Mika) 21 March 2007 (has links)
Abstract Chlamydia pneumoniae is a common, widespread pathogen that causes acute and chronic infections. Serological diagnosis of C. pneumoniae infection is primarily based on the microimmunofluorescence (MIF) method, but only a fourfold IgG antibody increase between paired sera and the presence of IgM antibodies have generally been accepted as markers of acute infection. At the present, no commonly accepted, reliable serological or other methods for the diagnosis of chronic C. pneumoniae infection exist. We evaluated C. pneumoniae specific serological tests in different populations, followed the kinetics of C. pneumoniae antibodies in multiple sera obtained from the same individuals, compared anti-human IgA FITC conjugates in MIF test and evaluated C. pneumoniae specific antibody tests before and after coronary events in case-control pairs matched for the time point of serum sampling, place of residence, and treatment. We showed that reinfection or reactivation is needed for the persistence of elevated IgG and IgA antibody levels. In chronic infections and upon reactivation, chronic processes may be better diagnosable based on IgA persistence than IgG levels because of the rapid disappearance of IgA levels after seroconversions. The cycle of reinfection and reactivation seems to be faster than previously thought in crowded conditions, such as in military service, since we recorded several antibody changes between the arrival and departure sera of military recruits during 6-month service. The presence of antibodies does not provide protection from reinfection. Commercial anti-human IgA conjugates act differently in MIF tests, and there is marked variation in their ability to detect IgA antibodies. The EIA test used here overestimated the prevalence and persistence of IgA antibodies when compared to MIF. The best compability between MIF and EIA antibody levels was seen in the participants with high titers. Only high IgA MIF titers to C. pneumoniae at the baseline predicted future coronary events. In the present study, seroconversions both in the participants who developed a coronary event and in the controls were detected by MIF and EIA, but mostly in different persons. Seroconversion suggesting reinfection or reactivation of persistent infection may have a role in accelerating chronic processes, because the participants with MIF seroconversion between consecutive sera had a slightly higher risk for coronary events than the controls. EIA seroconversions were more common in the controls than in the cases before the coronary event. The difference in the kinetics of EIA and MIF antibodies warrants future research and supports the use of the MIF method as a golden standard in the measurement of C. pneumoniae IgG and IgA antibody levels and seroconversions. In their diagnostic practice, laboratories should use, compare, and validate more C. pneumoniae IgA antibody tests in addition to IgG tests. Unspecific findings in C. pneumoniae EIA tests require re-estimation and a new way to interpret the results. Chlamydia experts should speak for MIF and rethink the meaning of IgA antibodies and recommendations in the diagnosis of C. pneumoniae infections.
47

Une nouvelle méthode d'épidémiologie moléculaire pour le chlamydia trachomatis le multi locus sequence typing

Ménard, Isabelle January 2011 (has links)
Les Chlamydiaceae sont une famille de bactéries relativement récente dans la systématique microbienne. Deux bactéries sont principalement associées à des pathologies de l'homme, soit Chlamydia trachomatis et Chlamydophila pneumoniae. C. trachomatis est la première maladie à déclaration obligatoire au Québec et l'infection sexuellement transmissible (ITS) le plus fréquemment rencontré dans le monde. Mon projet consistait au développement d'une méthode de"Multi Locus Sequence Typing" (MLST) pour C. trachomatis à partir d'isolats cliniques, sans passer par la culture cellulaire, et ce grâce au PCR (réaction en chaîne de la polymérase) multiplex niché. L'objectif ultime de cette technique est de mieux connaître l'épidémiologie de la bactérie, pour pouvoir comprendre la résistance et la persistance aux antibiotiques et l'origine géographique commune, par exemple. Outre les 15 isolats de référence, 115 isolats d'origines diverses (38 ITS de l'Estrie, 54 ITS de l'Afrique et 22 trachomes de l'Afrique) ont été testés par PCR multiplex niché puis séquencés. Globalement, les 130 isolats se séparent en 29 séquences-types différentes, dont 17 ne sont retrouvées qu'une seule fois. Ces STs se regroupent en 4 complexes clonaux distincts. De plus, les isolats sont séparés selon le type d'infection qu'ils causent, soit l'ITS, le trachome ou la lymphogranulomatose vénérienne. Dans son ensemble, l'évaluation de la pertinence et de la qualité de la nouvelle technique MLST montre une force discriminatoire de 90,1%, qui est dans les normes de qualité pour une technique d'épidémiologie moléculaire. Un index d'association de 3,809 pour le schéma complet est trouvé, et un de 2,447 lorsque le calcul est refait avec un exemplaire de chaque ST seulement, indiquant une population clonale forte. Finalement, un ratio d[indice inférieur N]/d[indice inférieur S] variant entre 0.145 et 0.773 pour les gènes choisis pour le schéma MLST démontre que les gènes sélectionnés ne sont pas soumis à une pression de sélection positive. Toutes ces données tendent à prouver que le nouveau schéma MLST est une technique discriminante, qui va permettre de faire des liens épidémiologiques intéressants pour C. trachomatis. De plus, au cours de ce projet, des analyses de certains isolats de C. trachomatis ont montré des caractéristiques nouvelles au niveau du génotype ompA.Les 22 isolats de trachome de la Tanzanie (Afrique) ainsi que 5 isolats ITS des Îles Comores ont cette particularité. Il s'agit selon la séquence d'un génotype A variant. Des analyses supplémentaires restent à faire pour caractériser complètement le génotype.
48

Detecção de Chlamydia trachomatis na doença inflamatória pélvica

Naud, Paulo Sergio Viero January 1989 (has links)
A Chlamydia trachomatis, bactéria pertencente ao grupo das doenças sexualmente transmissíveis, tem sido citada na gênese de casos de doença inflamatória pélvica. Para tanto foram investigadas 188 mulheres que procuraram o Serviço de Emergência do Hospital de Clínicas de Porto Alegre, com quadro clínico compatível com esse processo infeccioso. O grupo controle consistiu de pacientes do Ambulatório de Ginecologia e Obstetrícia deste mesmo Hospital num total de 83 mulheres, em que se fez a pesquisa para esta bactéria na cérvix uterina. No grupo de pacientes com doença inflamatória pélvica, fez-se uma subdivisão para um grupo de 26 prostitutas e um grupo que não relatava esta prática sexual, com 162 pacientes. Ao estudo estatístico, utilizando-se testes não paramétricos, o Qui Quadrado e o teste Fischer verificou-se que a prevalência de Chlamydia com trachomatis nestes dois grupos não apresentava significância estatística. Contudo, se comparados o grupo dom infecção pélvica em relação ao de pacientes ambulatoriais este demonstrou haver significância estatística para um p = 0,000002.
49

Chlamydia trachomatis, a cell adhesion architect : the role of TarP and CT228 in Chlamydia trachomatis modulation of host cell focal adhesions

Santos Tedim Sousa Pedrosa, António José January 2017 (has links)
Bacterial infection of mucosal epithelial cells triggers cell exfoliation to limit the dissemination of infection within the tissue. Therefore, mucosal pathogens must possess strategies to counteract cell extrusion in response to infection. Chlamydia trachomatis L2 spends most of its intracellular development in the non-infectious form, and premature extrusion of the host cell is detrimental to the pathogen. Here I show that Chlamydia trachomatis L2-infected cells exhibited increase adhesion as demonstrated by increased resistance to detachment by mild trypsinization. In addition, I observed an increase in the number and size of the focal adhesions of the Chlamydia trachomatis L2-infected cells. I demonstrated that this phenotype was not exclusive of C. trachomatis serovar L2 and that it was not restricted to a single type of cell line. Quantitative confocal and live-cell TIRF microscopy revealed that this bacterium actively modulated host cell focal adhesions by enhancing their stability. Infection conferred resistance to disassembly upon inhibition of myosin II or ROCK1 activity. Furthermore, I was able to demonstrate that the Chlamydia trachomatis effector TarP is able to colocalize to the sites of focal adhesions when ectopically expressed in mammalian cells. This resulted in increased number of the host cell focal adhesions. TarP was also able to confer resistance to myosin II inhibition, in a VBD-dependent manner. Also, I have found that C. trachomatis transmembrane protein CT228 cooperates with TarP to confer resistance to ROCK1 inhibition. Super resolution microscopy revealed a reorganisation of focal adhesions in Chlamydia trachomatis L2-infected cells. In summary, this work shows for the first time that Chlamydia trachomatis L2 uses TarP and CT228 to modulate the host cell focal adhesions. Finally, I have also described that both Chlamydia trachomatis L2 and TarP are able to alter the nanoscale architecture, this has never been reported in any other system.
50

Chlamydia trachomatis hits the brakes : effects of infection in tissue organization and collective cell migration

Teixeira Nogueira, Ana Celeste January 2017 (has links)
Chlamydia trachomatis infection targets the mucosal epithelium, where squamous and columnar epithelia can be found. Research on Chlamydia trachomatis-epithelia interaction has predominantly focused on columnar epithelia, with very little known on how Chlamydia trachomatis interacts with the squamous epithelium. The stratification and differentiation processes found in the squamous epithelium might influence chlamydial growth and infection dissemination. For this reason, 3D stratified squamous epithelial cultures were adapted to mimic the stratified squamous epithelium, and chlamydial infection was characterized. Chlamydia trachomatis infection in monolayers and 3D cultures were monitored by immunofluorescence and transmission electron microscopy to characterize inclusion growth and chlamydial interconversion between elementary and reticulate body. We observed that the stratified epithelium varied in susceptibility to Chlamydia trachomatis infection. The undifferentiated basal cells were susceptible to infection, while the terminally differentiated upper layers were resistant. If given access to the basal layer Chlamydia trachomatis is able to disseminate and disrupt the epithelial. This disruption have clinical relevance, such as facilitating secondary infection by other STIs. The use of a punch biopsy in 3D cultures revealed that infected samples were unable to close the wound as efficiently as the mock-infected sample. A simplified 2D wound healing assay confirmed these observations. Additionally, this correlated with a reorganization of hemidesmosomes in Chlamydia trachomatis-infected cells but, most importantly, in bystander uninfected cells within the infected sample. The lack of motility and the hemidesmosomes reorganization was shown to be dependent on myosin II contractility and the chlamydial protein CTL0480. This chlamydial protein recruits MYPT1 to the inclusion membrane, which could potentially prevent the cell from controlling the actomyosin tension. In summary, this is the first study to use a 3D stratified epithelial to determine how Chlamydia interacts with this physiologically relevant tissue. Most importantly, this work demonstrates that Chlamydia trachomatis is able to alter the organization of hemidesmosomes which has never been reported for any other bacterial pathogen.

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