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Human papillomavirus prevalence and expression in trophoblastic and cervical cells / Prévalence et expression des papillomavirus humains dans les cellules trophoblastiques et cervicalesWeyn, Christine 08 November 2010 (has links)
Human papillomavirus (HPV) is a double-stranded DNA virus, typically infecting mucosal or cutaneous epithelial keratinocytes. Today, more than 118 different HPV types have been formally described. Sexual transmission of mucosal HPVs is very common and generally asymptomatic, but HPV infection can be associated with benign lesions such as condylomata acuminata or, in rare cases, with malignant lesions such as cervical cancer. Two prophylactic vaccines are currently available in Europe, protecting against HPV-16 and HPV-18 (Cervarix&63720;) or against HPV-6, HPV-11, HPV-16 and HPV-18 (Gardasil&63720;). In order to assess the impact of the vaccination program, it is mandatory to obtain geographically widespread date on the baseline HPV prevalence and type distribution in cervical samples from women, presenting or not, normal or abnormal cytologic or histologic results. We undertook an epidemiological study in the Capital Region of Brussels to determine the HPV prevalence and type-distribution in 1526 cervical samples of women presenting a cytology within normal limits (WINL), atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intra-epithelial lesions (LSIL), high-grade squamous intra-epithelial lesions (HSIL) or invasive cervical cancer (ICC). The HPV prevalence was 10.8% (95%CI: 8.8-12.8) for NILM, 34.5% (95%CI: 28.3-40.8) for ASC-US, 54.0% (95%CI: 47.4-60.6) for LSIL and 100% for HSIL and ICC. With an HPV-16 and HPV-18 prevalence of 63.3% (95%CI: 44.1-67.7) and 73.5% (95%CI: 63.0-84.0) in mono-infected HSIL and ICC, respectively, HPV 16/18 L1 VLP vaccines would be expected to significantly reduce the management and treatment of women suffering from HSIL and ICC in the Capital Region of Brussels. We also detected HPV-30, HPV-53, HPV-66 and HPV-68 in mono-infected HSIL and ICC samples, possibly providing arguments for the reconsideration of the carcinogenicity of these types. <p>Vertical transmission of HPV was also previously reported, but in most cases one could not exclude a placental contamination by HPV positive cells from an infected birth canal. In order to confirm that the placenta can be infected with HPV, we analysed residual cells from 35 transabdominally obtained placental samples from pregnant women undergoing chorionic villous sampling for screening of suspected foetal abnormalities and found that two samples were positive for HPV-16 and HPV-62, respectively. The clinical importance of these results remains to be elucidated, but the previously observed association between placental HPV infection and pregnancy loss might gain further in importance. HPV gene regulation in placental trophoblastic cells has not been studied so far. We studied the HPV-16 early gene expression regulation in transiently transfected monolayer cultured trophoblastic cells with an HPV-16 long control region (LCR) driven reporter plasmid. We observed important differences in constitutive HPV-16 LCR activities between trophoblastic cell lines and could identify progesterone as an important inducer of HPV-16 early gene expression. Steroid hormones are induced during pregnancy and could therefore lead to an enhanced expression of the E5, E6 and E7 proteins upon placental HPV infection. Since these proteins were previously shown to affect trophoblast adhesion, survival, migration and invasion, their enhanced expression might eventually contribute to pregnancy loss. We furthermore found that the transcription of episomally maintained HPV-16 is not regulated by E2 or E1, but by E5, E6 and/or E7. <p> / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
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Impacts of Human Papillomavirus type 16 (HPV-16) early proteins on trophoblastic cells / Impacts des protéines précoces du virus du Papillome Humain de type 16 sur les cellules trophoblastiquesBoulenouar, Selma 13 January 2010 (has links)
Les infections génitales par les virus du papillome humains (HPV) sont les infections virales sexuellement transmises, les plus communes chez les femmes en âge de procréer. Il est désormais bien établi que l’infection persistante par les HPV classés «à haut risque» est l’un des facteurs indispensables au développement de lésions précancéreuses et cancéreuses du col de l’utérus. Ces HPV semblent aussi être impliqués dans le développement d’autres cancers de la région ano-génitale et pourraient être également impliqués dans les cancers de la tête et du cou. Durant cette dernière décennie, des études croissantes tendent à établir un rôle étiologique des HPV dans les dysfonctionnements gestationnels. La détection des ADN HPV dans les placentas issus d’avortements spontanés et leur capacité exceptionnelle à se répliquer in vitro dans les cellules trophoblastiques cultivées en monocouche, ont apporté de nouvelles perspectives quant à la possibilité que le placenta pourrait constituer aussi un tropisme naturel des infections par HPV.<p>Six jours après la fécondation et suite à l’accolement du blastocyste à l’épithélium utérin, le trophoblaste s’engage dans des processus actifs de prolifération, d’invasion et de différenciation complexe pour la construction de l’interface physiologique indispensable aux échanges essentiels entre la mère et l’enfant ;le placenta. De façon intéressante, ses propriétés sont similaires à celles de la cellule tumorale maligne. Néanmoins, ses mécanismes sont étroitement régulés dans le trophoblaste, à la fois dans l’espace et le temps, assurant un développement normal à chaque étape de la grossesse.<p>Devant toutes ces données, nous avions émis l’hypothèse que l’expression des protéines précoces E5, E6 et E7 d’HPV de type 16 (de haut risque), pourraient modifier le développement des trophoblastes infectés. Les résultats obtenus durant ce travail de doctorat démontrent que la protéine virale E5, hautement hydrophobe, est cytotoxique et affecte la viabilité du trophoblaste. Cette cytotoxicité est neutralisée, et la viabilité est améliorée, lorsque les oncoprotéines majeures E6 et E7 sont exprimées en présence de la protéine E5. Lorsque toutes les protéines précoces sont exprimées sous le contrôle de leur propre promoteur (LCR), la viabilité est favorisée. Ces observations ont été confirmées dans les cellules cervicales également. Il a été précédemment rapporté que les oncoprotéines E6 et E7 affectaient l’adhésion du trophoblaste aux cellules endométriales. Dans le présent travail, il a été retrouvé que la protéine E5 diminuait elle aussi l’adhésion, non seulement aux cellules endométriales, mais aussi au support de culture cellulaire. Les capacités de migration et d’invasion de la matrice extracellulaire sont augmentées par l’expression de E5 et dans une plus large proportion par l’expression de E6 et E7. Des résultats similaires ont été obtenus lorsque toutes les protéines de la région précoces sont exprimées sous le contrôle de leur propre promoteur (LCR). La diminution de l’expression de la E-cadhérine est considérée comme un marqueur de malignité et de mauvais pronostic pour les cancers. Nous avons démontré que l’expression de E5, E6 ou de E7, inhibait l’expression de la E-cadhérine, reflétant l’impact des oncoprotéines du virus HPV-16 sur la diminution de l’adhésion et l’augmentation du pouvoir invasif des cellules trophoblastiques. L’investigation d’autres marqueurs de malignité et de tolérance immunitaire, l’étude de l’impact du virus HPV-6 (de bas risque) sur la migration et l’invasion des cellules trophoblastiques, et l’étude de la capacité des protéines précoces d’HPV-16 à influencer l’entrée des particules virales, ont fait l’objet de résultats préliminaires, ouvrant de larges perspectives.<p><p><p>Genital Human Papillomavirus (HPV) infections are the most common sexually transmitted infections amongst women on the age of reproduction. It is well established that persistent infection with high-risk HPVs is the necessary factor in the causation of precancerous and cancerous cervical lesions. High-risk HPVs have also been reported to be involved in the causation of head and neck cancers and other anogenital cancers. On this last decade, growing data are attempting to study the potential etiological association of HPV with gestational dysfunctions. The detection of HPV DNA in placentas resulting from spontaneous abortions and the unique ability of multiple HPV types to replicate in vitro in trophoblastic cells cultured in a monolayer system, rise new questions over the HPV tropism. <p>Six days following fertilization and once the apposition of the blastocyst on the uterine wall takes place, the trophoblast, in a very active and complex process, starts to proliferate, invade and to differentiate in order to build a physiological interface; the placenta, from where multiple mother/foetus exchanges occur. Interestingly, the way that the trophoblast behaves is very similar to malignant tumoural cells. However, the trophoblast obeys to strict spatial-temporal regulatory confines, insuring a proper development all along the pregnancy.<p>In regard to these data, we hypothesised that the expression of the high-risk HPV type 16 oncoproteins E5, E6 and E7, might modify the development of the infected trophoblast. During my Ph.D study, I demonstrated that the highly hydrophobic protein E5 is localized in many interne membranes compartments of the transfected trophoblast. E5 affects the viability of transiently and stably transfected trophoblastic cells. E6 and E7, favouring cell growth, neutralised the E5 cytotoxic effect. All HPV-16 early proteins, when expressed under the control of their endogenous promoter (LCR), favoured trophoblastic growth. These observations were also observed in cervical cell lines. In addition, E5 decreased the adhesiveness of trophoblastic cells to the tissue culture plastic and to endometrial cells similarly as previously described for E6 and E7. Cells expressing E6, E7 and in less extend E5 favoured chemotaxic migration and matrigel invasion compared to the cells expressing the LacZ control. These effects were also observed when early proteins were expressed under the control of their own viral promoter (LCR). Interestingly, the E-cadherin was down regulated in trophoblastic cells expressing E5, E6 and E7. In conclusion, HPV-16 early proteins enhanced trophoblastic growth and intensify the malignant phenotype by impairing cell adhesion leading to increased cellular motile and invasive properties. HPV-16 E5 participated, with E6 and E7, in these changes by impairing E-cadherin expression, a hallmark of malignant progression. Additional preliminary results consisting on the investigation of other markers of malignancy and immune tolerance, on studying the impact of the low-risk HPV type 6 early proteins on the migratory and invasive properties of trophoblastic cells and on the study of the ability of HPV-16 to influence the entry of virus particules, allowed to open wide perspectives.<p><p><p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
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Social Network Simulation and Mining Social Media to Advance EpidemiologyCorley, Courtney David 08 1900 (has links)
Traditional Public Health decision-support can benefit from the Web and social media revolution. This dissertation presents approaches to mining social media benefiting public health epidemiology. Through discovery and analysis of trends in Influenza related blogs, a correlation to Centers for Disease Control and Prevention (CDC) influenza-like-illness patient reporting at sentinel health-care providers is verified. A second approach considers personal beliefs of vaccination in social media. A vaccine for human papillomavirus (HPV) was approved by the Food and Drug Administration in May 2006. The virus is present in nearly all cervical cancers and implicated in many throat and oral cancers. Results from automatic sentiment classification of HPV vaccination beliefs are presented which will enable more accurate prediction of the vaccine's population-level impact. Two epidemic models are introduced that embody the intimate social networks related to HPV transmission. Ultimately, aggregating these methodologies with epidemic and social network modeling facilitate effective development of strategies for targeted interventions.
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Gendering Gardasil: Framing Gender and Sexuality in Media Representations of the HPV VaccinePisciotta, Maura Kathleen 01 January 2012 (has links)
In an age of biomedicine, technologies, drugs, and treatments are expanding in new and diverse ways. Especially relevant to biomedicalization and this research is how such information is conveyed to the public through the media. Medical information is omnipresent in the media through direct-to-consumer (DTC) advertising and regular coverage of health topics in the news. The accessibility and proliferation of medical information provides an important opportunity to examine the ways in which these topics are framed in the media. This research specifically examines the framing of the HPV vaccine, Gardasil in the mass media. In this study, I explore how Gardasil was framed, how gender and sexuality were utilized within such frames, and what groups influenced these frames. I employ frame analysis to examine the presentation of Gardasil in the mass media. Due to the vaccine's intricate connection to gender and sexuality, I examine how these dimensions are utilized and reproduced in such frames. Gardasil was originally approved only for women, making gender a salient aspect of the vaccine. The current body of research examining Gardasil in the media presents data from the time the vaccine was only available to women. Now that the HPV vaccine is approved for men, this research seeks to contribute to a more comprehensive understanding of how Gardasil was framed in the media now that it is available to men and women. And given that Gardasil prevents a sexually transmitted infection (STI) in men and women, it is uniquely tied to issues of sexuality. To analyze Gardasil in the media, I examine newspaper articles, magazine articles, and media representations from stakeholder groups, including DTC advertising, official statements, and group websites. Analysis of key sources indicates that Merck dominated the framing of the vaccine in DTC advertisements and the news media, illustrating the power of the pharmaceutical industry. Findings indicate that the initial marketing of Gardasil constructed the vaccine as uniquely tied to femininity and later, women's empowerment. However, once the drug was approved for men, messages were reframed to appeal to a wider audience. Overall, the media continued to frame the vaccine specifically for women, further constructing HPV as a "woman's disease." The dominant focus on women concomitantly silenced the sexual health of men and sexual minorities. In conclusion, the marketing, discourse, and structural elements of Gardasil make it less accessible to those most in need, therefore contributing to the ongoing problem of cervical cancer and HPV.
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Human papillomavirus type distribution in cervical cancer in Indiana and BotswanaQadadri, Brahim January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In this study we compared the distribution of HPV types in cervical cancer specimens from women living in either Indiana or Botswana. Paraffin-embedded blocks of formalin-fixed cervical cancer specimens were identified from women living in Indiana (n=51) or Botswana (n=171)
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