Les hommes ayant des relations sexuelles avec d'autres hommes (HARSAH) ont un risque accru d'infections sexuellement transmissibles (IST). Les données sur les IST chez les HARSAH sont rares au Bénin. Cette étude visait à évaluer la prévalence et les facteurs associés à Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) et Treponema pallidum (TP) chez 204 HARSAH VIH-négatifs de Cotonou au Bénin initiant la prophylaxie préexposition en prévention du VIH. Un questionnaire a été complété et un médecin a réalisé un examen physique des participants. Des échantillons de sang, anaux, pharyngés et urinaires ont été prélevés. Les prévalences des IST ont été présentées avec un intervalle de confiance à 95% et la régression de Poisson a permis d'identifier leurs déterminants. La prévalence était de 18,6%, 15,2%, 9,8% et 27,9% pour CT, NG tous sites confondus, NG anorectal et l'infection par NG ou CT (NG/CT) respectivement. Les IST étaient généralement asymptomatiques (84,2% pour NG/CT) et de localisation extra-génitale (61,4% pour NG/CT). Un seul cas de syphilis non confirmée a été observé. En analyse multivariée, le fait d'avoir moins de 25 ans, de ne pas être célibataire et d'avoir plus de quatre partenaires féminines étaient associés à CT et NG/CT alors qu'un faible revenu mensuel était associé à NG/CT seulement. Le jeune âge, le sexe anal réceptif et ne pas avoir de rapports sexuels payants étaient associés à NG. Seul, le sexe anal réceptif était associé à NG anorectal. Les infections à NG et à CT sont fréquentes chez les HARSAH VIH-négatifs de Cotonou au Bénin. Leur caractère asymptomatique et extra-génital rend la prise en charge syndromique inefficace et le dépistage aux sites anal et pharyngé nécessaire. La syphilis est rare chez ces HARSAH. Les interventions de contrôle et de prévention des IST devraient cibler particulièrement les jeunes HARSAH et leurs partenaires sexuelles féminines. / Men who have sex with men (MSM) are at increased risk of sexually transmitted infections (STIs). Data on STIs among MSM are scarce in Benin. This study aimed to assess the prevalence and factors associated with Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and Treponema pallidum (TP) among 204 HIV-negative MSM in Cotonou, Benin initiating pre-exposure prophylaxis (PrEP) for HIV prevention. A questionnaire was completed, and participants underwent a physical examination by a physician. Blood, anal, pharyngeal, and urinary samples were collected. Prevalences are presented with a 95% confidence interval. Poisson regression was used to determine factors associated with STIs. The prevalence was 18.6%, 15.2%, 9.8% and 27.9% for CT, NG-all sites, anorectal NG, and infection by either NG or CT (NG/CT) respectively. STIs were generally asymptomatic (84.2% for NG/CT) and of extra-genital location (61.4% for NG/CT). Only one case of unconfirmed syphilis was observed. In multivariate analysis, younger age, not being single, having more than four female sexual partners were associated with CT and NG/CT while lower monthly income was associated with NG/CT alone. Younger age, receptive anal sex and paid sex were associated with NG. Only receptive anal sex was associated with anorectal NG. NG and CT infections are common among HIV-negative MSM in Cotonou, Benin. Their asymptomatic and extra-genital nature makes syndromic management ineffective and screening at anal and pharyngeal sites necessary. Syphilis is rare among these MSM. STI control and prevention interventions should target young MSM and their female sexual partners.

Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-02-13T12:08:13Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SoroepidemiologiaChlamydiaTrachomatis.pdf: 714575 bytes, checksum: 150b98376e7d5179deaf87cc15123665 (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-04-16T14:00:20Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SoroepidemiologiaChlamydiaTrachomatis.pdf: 714575 bytes, checksum: 150b98376e7d5179deaf87cc15123665 (MD5) / Made available in DSpace on 2014-04-16T14:00:20Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SoroepidemiologiaChlamydiaTrachomatis.pdf: 714575 bytes, checksum: 150b98376e7d5179deaf87cc15123665 (MD5) Previous issue date: 2010 / As bactérias do gênero Chlamydia estão associadas à diversas doenças, como cegueira, infecções genitais e pneumonia. Existem poucos dados sobre como a Chlamydia e o Treponema pallidum afetam indígenas na Amazônia brasileira. Este estudo objetivou determinar a soroprevalência das infecções pela Chlamydia trachomatis, Chlamydia pneumoniae e Treponema pallidum nas aldeias indígenas Bakajá, Apyterewa, Xingu e Mrotdidjãm, no município de Altamira, Pará, Brasil. O estudo incluiu 270 amostras de sangue coletadas no ano de 2007. A detecção de anticorpos das classes IgM e IgG anti-Chlamydia foi realizada empregando-se o ensaio imunoenzimático (ELISA), e selecionada de forma aleatória amostragem de 36, entre os positivos, para determinar a sorotipagem pela microimunofluorescência. Para detecção de anticorpos anti-T. pallidum foi utilizado um teste treponêmico (ELISA) e as amostras positivas foram submetidas a um teste não treponêmico (RPR). A prevalência geral de anticorpos anti-Chlamydia foi de 26,7%, com prevalência de 100% para C. trachomatis entre as amostras testadas pela MIF. Para a C. pneumoniae a prevalência foi de 61,1% e a prevalência de anticorpos contra Treponema pallidum foi baixa. As bactérias do estudo circulam nas comunidades indígenas da Amazônia brasileira estudada, o que requer uma resposta urgente das autoridades de saúde pública, pois estas bactérias podem causar doenças graves, mas são sensíveis a tratamento específico, quando diagnosticadas adequadamente. / Bacteria from the genius Chlamydia are associated with several diseases including blindness, reproductive tract infections and pneumonias. There is little data about Chlamydia and Treponema pallidum affects on native Indian population in the Brazilian Amazon region. This study determined the prevalence of infections by Chlamydia trachomatis, Chlamydia pneumoniae and Treponema pallidum in Altamira, Para- Brazil among the native Indian populations Bakaja, Apyretewa, Mrotidjam, Xingu and included 270 plasma samples collected in 2007; they were tested using an enzyme immunoassay (ELISA) for the detection of IgM and IgG antibodies to Chlamydia and random samples (36) was chosen from the positives for serotyping through a microimmunofluorescence assay (MIF). Antibodies anti-Treponema were detected using a treponemal (ELISA) test and the positive samples were subjected to a non-treponemal test (RPR). The overall prevalence of antibodies to Chlamydia was 26.7% with a 100% prevalence of C. trachomatis tested through MIF. Prevalence of antibodies to C.pneumoniae was 61.1% and the prevalence of antibodies to T. pallidum was low. This study of bacteria circulating in the Brazilian Amazon indigenous communities confirms that it is necessary for an urgent response from public health authorities, because these bacteria’s can cause serious illness. With adequate diagnoses these bacteria’s can be treated because they are sensitive to specific treatment.

Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-02-13T12:18:42Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SoroepidemiologiaChlamydiaTrachomatisChlamydia.pdf: 2065401 bytes, checksum: 1da33c9028340a826d8e01d04fe2f763 (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-04-22T13:32:53Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SoroepidemiologiaChlamydiaTrachomatisChlamydia.pdf: 2065401 bytes, checksum: 1da33c9028340a826d8e01d04fe2f763 (MD5) / Made available in DSpace on 2014-04-22T13:32:54Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SoroepidemiologiaChlamydiaTrachomatisChlamydia.pdf: 2065401 bytes, checksum: 1da33c9028340a826d8e01d04fe2f763 (MD5) Previous issue date: 2009 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A Chlamydia trachomatis e o Treponema pallidum compartilham com o HIV uma importante forma de transmissão: a via sexual. Por conta do comprometimento imunológico dos portadores de HIV, a C. pneumoniae pode apresentar um papel potencial em infecções respiratórias. Este trabalho objetivou a descrição da soroprevalência destes três agentes em portadores de HIV do Estado do Pará, Brasil. Entre setembro de 2007 a junho de 2008, foram coletadas 430 amostras de portadores de HIV em Belém, Pará. Estas foram submetidas a um ELISA para detecção de anticorpo IgG e IgM anti-Chlamydia e, dentre os positivos, uma amostragem aleatória foi escolhida e submetida à microimunofluorescência para sorotipagem. Para a detecção de anticorpos anti-Treponema pallidum foi feito um teste não treponêmico (RPR) e um teste treponêmico (ELISA). Os resultados obtidos foram analisados pelo teste do χ2. A prevalência geral de anticorpos anti-Chlamydia foi 64,2% (51,6% para IgG e 4% para IgM). A sorotipagem mostrou uma alta prevalência de C. trachomatis (100% tanto para IgG como IgM), e C. pneumoniae (73,5% IgG e 70,5% IgM), sendo que houve uma larga disseminação dos sorotipos que causam infecções genitais da Chlamydia trachomatis. A prevalência geral de anticorpos contra o Treponema pallidum foi de 34,9%, sendo que 7,3% apresentaram resultado laboratorial indicativo de sífilis. As variáveis que apresentaram associação com a infecção por Chlamydia e Treponema pallidum foram: o gênero masculino, maior idade, baixa escolaridade, número de parceiros por semana, a prática de sexo anal, homossexualismo/bissexualismo, uso de droga não-endovenosa, histórico de IST. Faz-se necessário tanto a conscientização como o monitoramento da população, para impedir a transmissão destes agentes e para a melhoria da qualidade de vida dos indivíduos portadores de HIV. / Chlamydia trachomatis and Treponema pallidum share the sexual route of transmission with HIV-1. In consequence of the compromise of the immune response among HIV-1 carriers, C. pneumoniae is a potential harassment in respiratory infections. The present study intended the description of the seroprevalence of those three agents among 430 HIV-1 infected persons residing in the State of Para, Brazil, attended at the State Reference Unit (URE-DIPE), between September 2007 to June 2008. Plasma samples were tested using an enzyme immuno assay for the detection of IgM and IgG antibodies to Chlamydia and those which elicited positive results were ramdomly selected for serotyping through a microimmunofluorescence assay. Antibodies to T. pallidum were detected using a flocculation reaction (RPR) and an enzyme immunoassay. Results were compared statistically using the Chi square test (χ2). The general prevalence to Chlamydia was 64.2% (51.6% IgG reactivity and 4% to IgM). Serotyping showed 100% reactivity to C. trachomatis (for both IgG and IgM), a high prevalence to C. pneumoniae (73.5% IgG and 70.5% to IgM) and a large distribution of reactivity to strains of C. trachomatis which cause genital infections. Prevalence of antibodies to T. pallidum was 34.9% and 7.3% showed laboratory evidence of syphilis. Infection with both pathogens were associated to several characteristics which included: higher prevalence among males, high age, low number of study years, high number of sexual partners, anal sexual relations, homosexual/bisexual habits, use of non injecting drugs and the history of sti. It is necessary not only the individual attention for prevention, but also the continuous monitoring to block transmission and the improvement of the well being of HIV-1 infected persons.

Chlamydia trachomatis serovars D-K are the leading cause of bacterially-acquired sexually transmitted infections in the United States. As an obligate intracellular pathogen, C. trachomatis infects columnar epithelial cells of the genital mucosae and can cause deleterious sequelae such as pelvic inflammatory disease, infertility, and ectopic pregnancy. Several chlamydial antigens reach the host cell cytosol prior to the natural release of chlamydiae at the end of the developmental cycle. While some of these extra-inclusion antigens traffic to the host cell surface, others remain intracellular where they are proposed to influence vital host cell functions and antigen trafficking and presentation. The research herein examines the escape and trafficking of the immunodominant chlamydial antigens MOMP, LPS, and cHsp60 within C. trachomatis serovar E-infected polarized human endometrial epithelial cells. Studies using high-resolution transmission electron microscopy (TEM) and immuno-TEM report the novel escape mechanism of chlamydial antigens via vesicles everted/pinched off from the inclusion membrane, an occurrence observed both in the presence and absence of the antibiotic azithromycin. These extra-inclusion vesicles were differentiated from Golgi vesicles and were shown to deliver chlamydial heat shock protein 60 (cHsp60)-homologs 2 and 3, but not homolog 1, to the infected cell surface. Examination of the iron-responsiveness of the three cHsp60 homologs by immuno-TEM revealed a significant increase in cHsp60-2 following iron deprivation. Further investigation of the trafficking of chlamydial MOMP and LPS antigens enveloped within the protective everted inclusion membrane vesicles within host cells involved density gradient centrifugation for the separation of epithelial secretory pathway components followed by SDS-PAGE and Western blot to determine whether the chlamydial antigen-containing vesicles could fuse with and deliver the antigens to host cell organelles. Coupled with immuno-TEM, these data confirmed the presence of major chlamydial antigens within the endoplasmic reticulum of infected host cells. Additionally, chlamydial lipopolysaccharide (LPS) was co-localized with CD1d, a lipid antigen-presenting molecule. Collectively, these studies (i) establish a novel escape mechanism for chlamydial antigens, (ii) identify cHsp60-2 as a marker of iron stress response in C. trachomatis, and (iii) define for the first time the host cell ER as a destination for selected chlamydial antigens during infection.

<p>In recent years molecular biology has become an integral part of the clinical laboratory. With an ever increasing number of methodologies and applications being presented each year it has increased our knowledge of how bacteria cause disease as well as our ability to predict disease outcome. </p><p>The main focus of this thesis has been to develop methods for identifying biomarkers and prediction methods for bacterial infectious diseases by taking advantage of the ever increasing possibilities of molecular biology. We applied cutting edge techniques in order to establish novel platforms for identifying and characterizing biomarkers of disease. </p><p>In paper one we describe a novel approach to measure levels of antibiotic resistance and viability of C. trachomatis, a method that is a clear improvement over existing techniques. In the second paper we describe the development of two assays designed to type pertussis toxin subunit 1 in circulating strains, in order to facilitate multi center studies for vaccine escape surveillance. In paper three we develop a novel microarray application designed to identify a large number of bacterial traits of H. pylori simultaneously with human genetic polymorphisms in order to identify a collection of risk factors that could be used as a prediction tool for gastric cancer risk. In the last paper we define the “antigenome” of H. pylori and identified 14 promising, previously unreported antigens as well as a number of potential biomarkers.</p><p>The platform technologies described in this collection of papers will hopefully help us identifying novel ways of fighting and predicting bacterial disease in future studies. </p>

In recent years molecular biology has become an integral part of the clinical laboratory. With an ever increasing number of methodologies and applications being presented each year it has increased our knowledge of how bacteria cause disease as well as our ability to predict disease outcome. The main focus of this thesis has been to develop methods for identifying biomarkers and prediction methods for bacterial infectious diseases by taking advantage of the ever increasing possibilities of molecular biology. We applied cutting edge techniques in order to establish novel platforms for identifying and characterizing biomarkers of disease. In paper one we describe a novel approach to measure levels of antibiotic resistance and viability of C. trachomatis, a method that is a clear improvement over existing techniques. In the second paper we describe the development of two assays designed to type pertussis toxin subunit 1 in circulating strains, in order to facilitate multi center studies for vaccine escape surveillance. In paper three we develop a novel microarray application designed to identify a large number of bacterial traits of H. pylori simultaneously with human genetic polymorphisms in order to identify a collection of risk factors that could be used as a prediction tool for gastric cancer risk. In the last paper we define the “antigenome” of H. pylori and identified 14 promising, previously unreported antigens as well as a number of potential biomarkers. The platform technologies described in this collection of papers will hopefully help us identifying novel ways of fighting and predicting bacterial disease in future studies.

Arginine decarboxylase is a key enzyme involved in the polyamine pathway of organisms. Pyruvoyl-dependent arginine decarboxylases are expressed in the form of proenzymes that self-cleave to form N-terminal [beta] and C-terminal [alpha] subunits generating an active pyruvoyl group at the [alpha] terminus. We have identified an archaeal homolog of a pyruvoyl-dependent arginine decarboxylase in Chlamydophila pneumoniae that could play a role in the persistence of the organism in the host. The recombinant enzyme showed highest activity at pH 3.4, which is the lowest optimum pH ever reported for a pyruvoyl dependent arginine decarboxylase. The proton-consuming decarboxylation raises intracellular pH, and thereby plays a role in acid-resistance. It could inhibit the pro-inflammatory nitric oxide synthase resulting in asymptomatic infection. A variant protein Thr⁵²Ser at the predicted cleavage site showed less pro-enzyme cleavage and activity compared to the wild-type. The homologs of arginine decarboxylase and flanking arginine-agmatine antiporter were also found in different biovariants of Chlamydia trachomatis. In the invasive L2 strain of C. trachomatis, the presence of a nonsense codon in the gene encoding arginine decarboxylase enzyme prevented the expression of an active enzyme. The variant protein with tryptophan replacing nonsense codon restored arginine decarboxylase activity. The non-invasive D strain of C. trachomatis had an intact arginine decarboxylase gene, but it was recombinantly expressed as a proenzyme that was uncleaved. The arginine-agmatine antiporters from both the strains were active and transported tritiated arginine into their cells. The polyamine pathway of the crenarchaeon Sulfolobus solfataricus uses arginine to make putrescine, but the organism lacks homologs of arginine decarboxylase. However, it has two paralogs of pyruvoyl dependent S-adenosylmethionine decarboxylase − SSO0536 and SSO0585. These enzymes were recombinantly expressed as pro-enzymes that self-cleaved into [beta] and [alpha] subunits. Even with a 47% amino acid sequence identity, the SSO0536 protein exhibited significant arginine decarboxylase activity whereas SSO0585 protein had significant S-adenosylmethionine decarboxylase activity. This is the first report of an S-adenosylmethionine decarboxylase enzyme showing alternative decarboxylase activity. The chimeric protein with the [alpha]-subunit of SSO0585 and [beta]-subunit of SSO0536 had arginine decarboxylase activity, suggesting that the residues responsible for substrate recognition are located in the amino terminus. / text

Chlamydia trachomatis (CT) can cause infertility and is the most common sexually transmitted infection (STI) of bacterial origin in Europe. Surveys in seven countries estimated a population prevalence of 1.4-3.0 % in people 18 to 44 years. Approximately 87% of those diagnosed in Sweden are 15-29 years. Since 1997, with the exception of 2009-2010, despite all efforts, CT has increased steadily in many European countries including Sweden. That made us investigate risk factors associated with catching STIs, especially CT. In Sweden partner notification is mandatory by law when a patient is diagnosed with CT. Centralised partner notification, performed by a few experienced counsellors, and evaluation of the sexual history for at least 12 months back in time, shows superior results compared to other studies. Phone-interviews are a good option in remote areas. “The Västerbotten model” for partner notification fulfils these criteria and our evaluation has functioned as a model for changing recommendations of partner notification in Sweden. Preventing CT by primary prevention such as information and counselling is, however, still of great importance. We investigated whether it was necessary to test for CT in the throat. We found that patients testing positive for pharyngeal CT neither had more symptoms or signs nor a sexual history that differed from others. We therefore believe that we will find most or all of these patients by conventional testing of urine and cervical/vaginal samples. We wanted to further identify risk factors among patients attending a clinic for sexually transmitted infections to enable individualized care depending on risk. None or inconsistent use of condoms with new/temporary partners in combination with having at least one new/temporary partner within the past 6 months could identify persons with risk behaviour and at increased risk of CT (re)infection. Additional information about whether the condom was used during the whole intercourse did not add any risk of infection. A drop-in reception is a good contribution to an opportunistic screening approach. The rate of CT infected is high and the clinic attracts men and individuals ≥25 years old at risk of infection, groups which usually have a reduced test rate. The mean age was 28 years and 58% of the patients were men. The figure of correct condom usage is very low indicating the need for risk reducing counselling also in this grown-population. Among adult STI patients anxiety was common and depression uncommon. Neither was linked to high risk sexual behaviour nor ongoing CT infection. Hazardous alcohol consumption, however, was common and linked to anxiety and high risk sex. We conclude that preventive work can not only focus on STI prevention, but must consider the high frequency of hazardous alcohol consumption, which probably is contributing to sexual risk behaviour.

Although Sweden invests a great deal of money and effort in prevention work, STIs are a major problem in our society. Young people are at high risk both when it comes to unwanted pregnancies and STIs and several studies have revealed that the condom use is quite low. Condom use is a complex issue. There are often several factors that interact and affect the decision to use or not use condom. The result in this thesis shows that young people have behavioral expectation to use condom, especially for anal sex and vaginal sex with a casual partner (both known and unknown). At the same time, the condom use is low irrespective of type of partner and type of sex. Approximately 20 % of the participants never used a condom during the preceding 12 months. Most of the participants said that reason for their use or non-use was based on partner evaluation. However, our participants indicate that there often is a deeper reason why they do not use condoms. Women talk about their male partner’s resistance against condom use. Men in the other hand mention the problem with fit and feel especially problems related to erection problems when they have been drinking alcohol. One of the most interesting findings is that the participants’ view of sex affected their condom use. Those with a relaxed view (e.g., did not connect love with sex and had had more sexual partners during the past 12 months) had fewer occasions of unprotected vaginal intercourse compared with the participants with a traditional view (e.g., often associated sex with vaginal penetration).The most important thing we need to do is increase ’men’s sense of responsibility and involve them in the prevention work. It is also important that the condom counseling is individualized. It is not enough to simply speak about condom use in general; instead we need to relate condom use to sexual practice and partner type but also to the individuals’ specific condom problem. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Epub ahead of print. Paper 2: Manuscript. Paper 3: Manuscript.</p>

Chlamydia trachomatis is an obligate intracellular bacterium of major human health concern, causing urogential chlamydia infections, lymphogranuloma venereum (LGV) and trachoma. Chlamydia is one of the most common sexually transmitted infections worldwide and can cause infertility. In the first four papers described herein we used a high resolution multilocus sequence typing (MLST) system to investigate the epidemiology of C. trachomatis, and showed that MLST is superior to conventional ompA genotyping with respect to resolution. In the fifth paper we simplified the methodology by developing and validating a multilocus typing (MLT) DNA microarray based on the MLST system. In more detail, MLST analysis of consecutive specimens from 2006 in Örebro County in Sweden, and comparison to specimens from 1999-2000, showed that the new variant C. trachomatis (nvCT) is monoclonal and likely has appeared in recent years. MLST analysis of LGV specimens from men who have sex with men (MSM) showed that the increase of LGV in Europe in the last decade indeed was a clonal outbreak, contrary to the USA where LGV might have been present all along. In the third paper, clinical symptoms could not be correlated with the MLST genotypes, suggesting, together with the combined results of all previous studies, that bacterial factors, if important, need to be understood in the context of host factors. MLST analysis of specimens from a high incidence C. trachomatis area in North Norway revealed interesting epidemiological details concerning unusual genetic variants, the nvCT and MSM, but found no significant difference in genetic diversity compared to two other geographic areas in Norway. Lastly, we developed a MLT array that provides high resolution while being rapid and cost-effective, which makes it an interesting alternative for C. trachomatis genotyping. In conclusion, the MLST system and the MLT array have proven to be useful tools and should now be applied in further investigations to improve our understanding of C. trachomatis epidemiology.