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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.
241

Análise clínica e molecular de pacientes não tabagistas e não etilistas com carcinoma epidermóide de cabeça e pescoço / Clinical and molecular analysis of non smoking and non drinking patients with head and neck squamous cell carcinoma

Moysés, Raquel Ajub 08 April 2011 (has links)
O carcinoma epidermóide de cabeça e pescoço (CECP) é um problema de saúde relevante no mundo, por sua prevalência e agressividade. Os papéis do tabaco e do álcool estão bem definidos na sua etiologia, mas uma minoria crescente dos pacientes acometidos pela doença não é tabagista ou etilista. A infecção pelo papilomavirus humano (HPV) parece ser responsável por parte desses casos. Sugere-se que o CECP que acomete pacientes não tabagistas e não etilistas (NTNE) tenha processos carcinogênicos e evolução clínica distintos daqueles de pacientes tabagistas e etilistas (TE). Os objetivos desse estudo foram verificar se os aspectos demográficos, clínicos e histopatológicos de pacientes com CECP são diferentes conforme os hábitos tabágico e etílico; verificar se os CECPs de pacientes NTNE e TE diferem em relação à positividade para HPV; e comparar a sobrevida específica pela doença e a expressão de marcadores biológicos em amostras tumorais e de mucosa normal do trato aerodigestório de pacientes NTNE e de pacientes TE. Para tanto, realizamos estudo transversal de pacientes com carcinomas epidermóides de cavidade oral (exceto lábio), orofaringe, laringe e hipofaringe, prospectivamente incluídos em um banco de tumores de CECP de 2001 a 2009, pelo grupo de pesquisa multi-institucional GENCAPO. Seus dados demográficos, clínicos e patológicos foram analisados conforme os hábitos de tabagismo e etilismo. Através de análise de pareamento, pacientes NTNE e TE foram comparados em relação à sobrevida, à positividade para o HPV no tumor por reação em cadeia da polimerase (PCR) e aos marcadores imunohistoquímicos p53, FHIT, Ki-67, VEGF, EGFR e p16 tanto em amostras tumorais como de epitélio não tumoral. Dos 1633 pacientes selecionados, 80 eram NTNE (4,9%), 1374 TE (84,1%), 140 tabagistas atuais ou no passado mas não etilistas (TNE:8,6%) e 39 apenas etilistas atuais ou no passado, mas não tabagistas (NTE:2,4%). O grupo de pacientes NTNE constituiu-se principalmente por mulheres, preferencialmente idosas, com tumores da cavidade oral, diferentemente de pacientes tabagistas e/ou etilistas (p<0,001). Considerando os diferentes padrões de hábitos, pacientes TE eram geralmente mais jovens (p<0,001), pacientes TNE apresentaram proporcionalmente mais tumores de laringe (p<0,001) e pacientes NTNE apresentaram menor número de parentes de primeiro grau tabagistas (p<0,001). Observou-se um provável efeito do álcool na ocorrência de metástases ganglionares (p<0,001), enquanto o tabaco pareceu relacionar-se a menor grau de diferenciação tumoral à histologia e a menores índices de massa corpórea (p<0,001). Detectou-se a presença de material genético do HPV em 32,8% dos tumores de pacientes NTNE. Desses tumores positivos para o HPV, metade apresentou também hiperexpressão pelo p16. Foi observado menor risco de óbito pela doença em pacientes NTNE quando apresentavam expressão tumoral intensa do p16 (p=0,011 / RR = 0,07; IC 0,01-0,55) e menor sobrevida se apresentavam marcação pelo FHIT em camada basal de margem não tumoral (p= 0,031). Ao comparar pacientes NTNE e TE, não se observaram diferenças na sobrevida específica pela doença ou na positividade para o HPV de forma independente de sexo, idade, sítio tumoral, grau de diferenciação, variante morfológica, estádio T e presença de metástases linfonodais. Pacientes NTNE apresentaram marcação nuclear pelo FHIT em camada basal menos frequentemente do que pacientes TE (p=0,021) / Head and neck squamous cell carcinoma (HNSCC) is a major health problem worldwide, due to its prevalence and aggressiveness. The role of tobacco and alcohol in its etiology is well established; however, a growing minority of patients with HNSCC neither smokes nor consumes alcohol. Human Papillomavirus (HPV) infection seems to be responsible for some of these cases. It is suggested that HNSCC affecting non smoking and non drinking (NSND) patients has different carcinogenesis and outcomes than those in smoking and drinking (SD) subjects. The objectives of this study were to test if demographic, clinical and pathological aspects of patients with HNSCC vary according to smoking and drinking habits; to test if HNSCC in NSND and SD patients differ in terms of HPV positivity; and to compare NSND and SD patients with HNSCC according to survival and biomarkers in tumor and mucosal samples of the aerodigestive tract. We conducted a cross-sectional study of patients with oral cavity (lips excluded), oropharynx, larynx and hypopharynx tumors prospectively included in a multi-institutional HNSCC tumor bank - GENCAPO, from January 2001 to February 2009. Demographic, clinical and pathological data were analyzed in regards of smoking and drinking habits. Using matched-pair analysis, we compared NSND and SD patients in relation to disease-free survival, HPV positivity through polymerase chain reaction (PCR) and Immunohistochemical staining of p53, FHIT, Ki-67, VEGF, EGFR and p16 biomarkers in tumor and mucosal samples. From 1633 patients, 80 were NSND (4.9%), 1374 SD (84.1%), 140 current or past smokers, but non drinkers (SND:8.6%) and 39 current or past drinkers, but non smokers (NSD:2.4%). NSND patients were most frequently women, remarkably elderly, with oral cavity cancers more commonly than the other groups (p<0.001).Comparing to the other groups, SD patients were younger (p<0.001); SND patients were more frequently affected by larynx tumors (p<0.001) and NSND patients had fewer smoking first degree relatives (p<0.001). We observed that alcohol may influence the presence on node metastasis (p<0.001) whereas tobacco may be related to less differentiated tumors and lower body mass indexes (p<0.001). We found HPV DNA in 32.8% of tumors of NSND subjects. Half of the HPV positive tumors were also positive for p16 staining. A lower risk of death from disease was observed among NSND patients with intense p16 staining (p=0.011 / RR = 0.07; CI 0.01-0.55) and lower survival rates in patients with positive nuclear staining for FHIT at the basal layer of mucosal epithelium (p=0.031). We found no differences in disease-free survival of NSND and SD patients in an independent manner of gender, age, tumor site, differentiation grade at histology, pathological variants, T stage and the presence of node metastasis. NSND patients presented less frequently with nuclear staining for FHIT at the basal layer of mucosal epithelium than SD patients (p=0.021)
242

Seleção de motivos semelhantes a  Papilomavírus, a partir de bibliotecas de phage display, que apresentem potencial aplicação translacional / Search for Papillomavirus-like motif with Potential Translational Application Selected by Phage Display

Sulaiman, Lanre Precieux Kabir 16 November 2017 (has links)
O vínculo entre papilomavírus humano de alto risco e câncer cervical está bem estabelecido. Apesar da existência de vacinas profiláticas contra infecções pelos tipos mais comuns de HPV, para infecções e tumores causados por esses vírus as alternativas terapêuticas são restritas. Encontramos alguns motivos com homologias para proteínas do HPV de alto risco durante o imunoscreening de uma biblioteca de phage display com soros de participantes HPV-16-soropositivos da coorte Ludwig-McGill. Após enriquecimento das sequências, os bacteriófagos recombinantes foram purificados e amplificados para uso como imunógenos.Usando uma abordagem profilática, nós vacinamos experimentalmente camundongos imunocompetentes com um dos nossos bacteriófagos recombinantes, usando o bacteriófago sem inserto como controle. Estes camundongos foram então desafiados com células tumorais TC-1 (HPV-16 positivas), tendo-se avaliado as respostas imunes disparadas durante a progressão tumoral. Também usamos uma abordagem terapêutica, aonde os camundongos foram primeiro injetados com as células tumorais e imunizados com o bacteriófago após o estabelecimento do tumor. O crescimento tumoral foi monitorado e os tumores, baço e linfonodos foram avaliados quanto à quantidade e qualidade da resposta imunológica. Os testes de ELISA revelaram que todos os camundongos vacinados responderam à imunização com os diferentes bacteriófagos. O crescimento tumoral foi significativamente reduzido nas imunizações profiláticas e terapêuticas, embora a redução do tumor fosse mínima quando os camundongos foram tratados 9 dias após o enxerto. A redução no crescimento tumoral também se traduziu em uma sobrevivência significativamente maior para os camundongos imunizados. Estudos de infiltração celular não revelaram alterações em diversas sub-populações imunes, mas uma tendência de aumento de linfócitos T citotóxicos foi observada nos camundongos imunizados com PEP1 (bacteriófago contendo inserto). A importância deste aumento de CD8 na redução observada do crescimento tumoral foi confirmada utilizando camundongos CD8-knockout, onde a redução do crescimento tumoral previamente observada foi anulada. Foi observado um aumento de taxa CD8:CD4 nos camundongos imunizados e isto é uma indicação de ambiente tumoral citotóxico. Os ensaios de proliferação celular para testar a especificidade do antígeno dos linfócitos dos camundongos imunizados foram, no entanto, inconclusivos; da mesma forma, não pudemos alterar o padrão observado com o uso de adjuvante CpG. A utilidade da técnica de phage display também foi observada neste trabalho experimental. Trabalhos adicionais para entender o mecanismo de ação desses fagos recombinantes no controle do crescimento de tumores causados por HPV e seu potencial imuno-estimulador são necessários / The link between high-risk human papillomavirus and cervical cancer is well established. Despite the existence of prophylactic vaccines against infections by the most common types of HPV, therapeutic alternatives are limited for infections and tumors caused by these viruses. We found some homology motifs for high-risk HPV proteins during the immune-panning of a phage display library with sera from HPV-16- seropositive participants of the Ludwig-McGill cohort. After enrichment of the sequences, the recombinant bacteriophages were purified and amplified for use as immunogens. Using a prophylactic approach, we vaccinated experimentally immunocompetent mice with one of our recombinant bacteriophages using the insertless bacteriophage as a control. These mice were then challenged with TC-1 tumor cells (HPV-16 positive), and the immune responses triggered during tumor progression were evaluated. We also used a therapeutic approach where mice were first injected with tumor cells and immunized with the bacteriophage after tumor establishment. Tumor growth was monitored and tumors, spleen and lymph nodes were evaluated for the quantity and quality of the immune response. ELISA tests revealed that all vaccinated mice responded to immunization with the different bacteriophages. Tumor growth was significantly reduced in prophylactic and therapeutic immunizations, although tumor reduction was minimal when mice were treated 9 days after TC-1 cells grafting. The reduction in tumor growth also translated into a significantly greater survival for the immunized mice. Cell infiltration studies did not reveal changes in several immune subpopulations, but an upward trend in cytotoxic T lymphocytes was observed in mice immunized with PEP1 (insert-containing bacteriophage). The importance of this increase in CD8 in the observed reduction of tumor growth was confirmed using CD8-knockout mice, where the previously observed reduction of tumor growth was abolished. An increase in CD8:CD4 rate was observed in the immunized mice and this is an indication of a cytotoxic tumor environment. Cell proliferation assays to test the antigen specificity of lymphocytes from immunized mice were, however, inconclusive; likewise, we could not change the pattern observed with the use of CpG adjuvant. The usefulness of the phage display technique was also observed in this experimental work. Additional studies to understand the mechanism of action of these recombinant phages in the control of HPV tumor growth and its immunostimulatory potential are warranted
243

Les papillomavirus Humains dans les cancers des Voies Aéro-Digestives Supérieures : optimisation de méthodes de détection et étude de populations à risque / Human Papillomavirus in Head and Neck cancer : optimization of detection methods and study of risk populations

Guillet, Julie 01 April 2016 (has links)
Les Papillomavirus Humains (HPV) sont responsables de près de 100% des cancers du col utérin. Récemment, ces HPV sont apparus comme étant aussi la cause de certaines tumeurs des voies aérodigestives supérieures, et particulièrement des carcinomes épidermoïdes de l’oropharynx. En France, la proportion des tumeurs oropharyngées HPV-induites est mal connue, notamment parce que le dépistage viral n’est pas recommandé. De plus, il est difficile d’évaluer la proportion de tumeurs HPV positives dans les tumorothèques car les échantillons tumoraux sont fixés dans du formol puis inclus en paraffine (FFIP), ce qui complexifie les techniques de détection. Nous avons, au cours de nos travaux, testé une méthode de détection des HPV à haut risque oncogène indiquée pour le traitement des frottis en phase liquide. Nous l’avons mise à l’épreuve sur des prélèvements FFIP et comparée à la technique de référence qu’est la PCR (Polymerase Chain Reaction) suivie d’une électrophorèse sur gel. Nos résultats indiquent que cette technique est applicable aux prélèvements tissulaires et apparaît même comme étant plus sensible. En France, deux tiers des patients atteints de tumeurs des VADS sont pris en charge à des stades tardifs. Ceci s’explique en partie par l’absence de dépistage organisé de ces cancers. Nous avons donc mené une étude prospective sur des patients atteints d’une tumeur des VADS afin de tester le frottis oral comme technique de dépistage des cancers mais également des infections par les HPV. Nos résultats indiquent que le frottis a une spécificité proche de celle de la biopsie (94,4%) pour le dépistage des cancers des VADS, mais une moindre sensibilité (66,7%). Cette étude nous a permis de mettre en évidence une tumeur HPV-induite dans 12,2% des cas. Parmi eux, nous avons détecté grâce à un frottis buccal (en zone saine) une infection par un HPV à haut risque oncogène dans 53,3% des cas. L’OMS a classé les HPV comme agents carcinogènes depuis 1995, et a établi que les patientes ayant développé un cancer du col utérin avaient un risque 6 fois plus élevé de développer une autre tumeur HPV-induite. Dans ce contexte, nous avons prévu une étude prospective multi-centrique visant à dépister une infection orale par un HPV oncogène chez des patientes porteuses d’une lésion pré-néoplasique ou néoplasique du col utérin. Le taux de co-infection des deux sites anatomiques est inconnu chez les femmes infectées au niveau génital. Dans la mesure où l’infection orale pourrait être à l’origine d’une seconde localisation tumorale, il semble important d’en connaître la proportion afin de proposer par la suite un suivi particulier aux populations « à risque ». Au-delà des traitements des cancers avérés se pose la question de la vaccination préventive, qui existe contre les HPV 16 et 18 dans la prévention des cancers du col utérin. Le type 16 étant retrouvé dans 90% des tumeurs épidermoïdes de l’oropharynx HPV-induites, l’extension des recommandations vaccinales apparaît comme une nouvelle question de santé publique / The Human Papillomavirus (HPV) are involved in almost 100% of cervical cancers. Recently, HPVs have been recognized as the cause of tumors of the upper aerodigestive tract, especially of squamous cell carcinoma of the oropharynx. In France, the proportion of oropharyngeal HPV-related tumors is unknown, partly because viral testing is not in guidelines. Moreover, assess the proportion of HPV-positive tumors in tumor banks is difficult because the tumor samples were fixed in formalin and embedded in paraffin (FFPE), which complicates detection techniques. We tested a high risk HPV detection method, indicated for liquid based pap smear, on FFPE samples. We compared this technique to the gold-standard : PCR (Polymerase Chain Reaction) followed by electrophoresis. Our results indicate that this technique is applicable to FFPE samples and even appears to be more sensitive. The majority of French patients (2/3) with head and neck consult with an advanced stage of disease. This is explained in part by the lack of organized screening of these cancers, contrary to breast, prostate, cervical, or colorectal cancers. But an early treatment is essential to increase the survival rate. We therefore conducted a prospective study on patients with head and neck tumors to test the oral brushing as screening cancer and HPV detection. We found tumor and/or dystrophic cells in 97.8% of patients with biopsy, and in 88.9% of patients by brushing. Compared with biopsy, our results suggested that smear has similar specificity for HPV detection in tumors (94.4%), but lower sensitivity (66.7%). This study has shown an HPV-related tumor in 12.2% of cases. Among them, we detected by brushing (in healthy area) an oral infection by high-risk HPV in 53.3% of cases. WHO has classified HPV as carcinogenic agents since 1995, and determined that patients who developed cervical cancer are six-times more likely to develop another HPV-related tumor. In this context, we have planned a multicenter prospective study to detect oral HPV infection in patients with a pre-neoplastic or neoplastic lesion of the cervix. Co-infection rate of the two anatomical sites is unknown in women infected with genital level. Insofar oral infection could be the cause of a second tumor location, it seems important to know how much women are co-infected to propose thereafter a special monitoring. The preventive vaccination, which exists against HPV 16 and 18 in the prevention of cervical cancer, is a future perspective. Because HPV 16 is found in 90% of HPV-related squamous cell carcinoma of the oropharynx, extending vaccine recommendations emerge as a new public health issue
244

Conhecimento, atitude e prática do exame Papanicolaou em mulheres idosas

Oliveira, Caio Medeiros de 13 December 2017 (has links)
Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-08-09T13:51:45Z No. of bitstreams: 1 CaioMedeirosdeOliveiraDissertacao2017.pdf: 2350734 bytes, checksum: 06c738ae1c56496a4bfc724fd961a332 (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-08-09T13:51:58Z (GMT) No. of bitstreams: 1 CaioMedeirosdeOliveiraDissertacao2017.pdf: 2350734 bytes, checksum: 06c738ae1c56496a4bfc724fd961a332 (MD5) / Made available in DSpace on 2018-08-09T13:51:58Z (GMT). No. of bitstreams: 1 CaioMedeirosdeOliveiraDissertacao2017.pdf: 2350734 bytes, checksum: 06c738ae1c56496a4bfc724fd961a332 (MD5) Previous issue date: 2017-12-13 / Population aging is one of the greatest challenges for mordern public health. As a reflection of the enhancement in quality of life, there is a maintenance of the entire exercise of sexuality in the elderly and, with it, the risks of contracting Sexually Transmitted Infections (STIs), among them Human Papillomavirus (HPV) infection. The persistence of high-risk HPV infection associated with low tracking of the female population are the main factors responsible for the development of cervical carcinoma, which represents a significant cause of morbimortality in this age group. This research intent to characterize the profile of elderly women in Gama - Federal District, with emphasis on the preventive aspects of cervical cancer, comparing the profile and attitude of the elderly women before the colpocitological examination, regarding to their expertise of the exam. It is an evaluative study of the type inquiry knowledge, attitude and practice. The data collection was through a survey , under a direct hearing, addressing aspects concerning Knowledge, Attitude and Practice (KAP) of the elderly women in relation to the cervical cancer preventive exam (CCPE). The KAP surveys were applied to 300 elderly women, aged 60 and 93, passers-by at Gama in places such as public fairs, shopping malls and cultural and leisure centers for the elderly. The majority were married (43.3%), had elementary education (60.3%), resident near the health unit (83.7%) and had coitarche after 18 years (70.3%). The data collected displayed: as to Knowledge, 4.7% responded adequately; As for Attitude, 93.0% were considered adequate; and in practice, 50.7% were adequate. As far as knowledge was concerned, no significant correlation was observed with sociodemographic factors, whereas in relation to Attitude there was a statistically significant correlation with schooling, being higher in those with higher education. In the practice question there was a significant association with the age of the consulted women, being more appropriate in those with age group of 60 to 64 years. Evaluating the identification of the perception regarding the preventive examination of cervical cancer of the women interviewed, knowledge needs to be enhanced in order to develop the practice, which is below the desired level in this City. At the district level, the understanding of cervical cancer tracking is a relevant problem that requires the attention of the authorities in order to perform actions aimed at reducing the incidence of this disease and promoting early detection. Health promotion for the elderly is an important item in public policies, respecting the dignity of the elderly and avoiding unnecessary examinations, which onus public capital. / O envelhecimento populacional constitui um dos maiores desafios para a saúde pública contemporânea. Como reflexo da melhoria na qualidade de vida, há manutenção do pleno exercício da sexualidade na terceira idade e, com ele, os riscos de contrair Infecções Sexualmente Transmissíveis (IST’s), dentre elas a infecção por Papilomavírus Humano (HPV). A persistência da infecção pelo HPV de alto risco associada ao rastreamento deficiente da população feminina são os principais fatores responsáveis pelo desenvolvimento do carcinoma de colo uterino, que representa causa expressiva de morbimortalidade nesta faixa etária. Esta pesquisa visou caracterizar o perfil de idosas residentes na Região Administrativa do Gama - Distrito Federal (DF), com destaque nos aspectos preventivos do câncer de colo uterino, comparando-se o perfil e atitude das idosas frente ao exame colpocitológico, atrelados ao seu nível de conhecimento acerca do referido exame. Trata-se de estudo avaliativo do tipo inquérito conhecimento, atitude e prática. A coleta de dados foi realizada por meio de um questionário, sob entrevista direta, abordando aspectos concernentes a Conhecimento, Atitude e Prática (CAP) das idosas em relação ao exame preventivo do câncer de colo uterino (EPCCU). Os inquéritos CAP foram aplicados a 300 idosas, com idade de 60 e 93 anos, transeuntes em locais de livre circulação do Gama-DF como feiras públicas, shoppings e centros de cultura e lazer para idosos. A maioria era casada (43,3%), possuía ensino fundamental (60,3%), morava próximo à unidade de saúde (83,7%) e teve coitarca a partir dos 18 anos (70,3%). Os dados coletados mostraram: quanto ao Conhecimento, 4,7% responderam adequadamente; quanto à Atitude, 93,0% apresentaram esta considerada adequada; e quanto à Prática, 50,7% foram adequadas. No que tange ao conhecimento não foi observada correlação significativa com os fatores sociodemográficos, enquanto em relação à Atitude houve correlação estatisticamente significativa com a escolaridade, sendo maior naquelas com ensino superior. No quesito Prática, houve associação significativa com a idade das idosas entrevistadas, sendo mais adequada naquelas com faixa etária de 60 a 64 anos. Avaliando-se a identificação da percepção frente ao exame preventivo do câncer de colo uterino das mulheres entrevistadas, o conhecimento precisa ser aprimorado para que se tenha uma melhoria na prática, que se encontra aquém do desejado nesta Região Administrativa. Em nível regional, a compreensão do rastreamento do câncer de colo uterino apresenta-se como um problema relevante que necessita da atenção das autoridades, a fim de executar ações voltadas à redução da incidência desta moléstia e à promoção de uma detecção precoce. A promoção à saúde dos idosos é item importante das políticas públicas, respeitando a dignidade da pessoa idosa e evitando realização de exames desnecessários, que oneram os fundos públicos.
245

Epidemiology of cervical human papillomavirus infection in Hong Kong. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2002 (has links)
Chan Kay Sheung Paul. / "December 2002." / Thesis (M.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 225-254). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.
246

Seleção de motivos semelhantes a  Papilomavírus, a partir de bibliotecas de phage display, que apresentem potencial aplicação translacional / Search for Papillomavirus-like motif with Potential Translational Application Selected by Phage Display

Lanre Precieux Kabir Sulaiman 16 November 2017 (has links)
O vínculo entre papilomavírus humano de alto risco e câncer cervical está bem estabelecido. Apesar da existência de vacinas profiláticas contra infecções pelos tipos mais comuns de HPV, para infecções e tumores causados por esses vírus as alternativas terapêuticas são restritas. Encontramos alguns motivos com homologias para proteínas do HPV de alto risco durante o imunoscreening de uma biblioteca de phage display com soros de participantes HPV-16-soropositivos da coorte Ludwig-McGill. Após enriquecimento das sequências, os bacteriófagos recombinantes foram purificados e amplificados para uso como imunógenos.Usando uma abordagem profilática, nós vacinamos experimentalmente camundongos imunocompetentes com um dos nossos bacteriófagos recombinantes, usando o bacteriófago sem inserto como controle. Estes camundongos foram então desafiados com células tumorais TC-1 (HPV-16 positivas), tendo-se avaliado as respostas imunes disparadas durante a progressão tumoral. Também usamos uma abordagem terapêutica, aonde os camundongos foram primeiro injetados com as células tumorais e imunizados com o bacteriófago após o estabelecimento do tumor. O crescimento tumoral foi monitorado e os tumores, baço e linfonodos foram avaliados quanto à quantidade e qualidade da resposta imunológica. Os testes de ELISA revelaram que todos os camundongos vacinados responderam à imunização com os diferentes bacteriófagos. O crescimento tumoral foi significativamente reduzido nas imunizações profiláticas e terapêuticas, embora a redução do tumor fosse mínima quando os camundongos foram tratados 9 dias após o enxerto. A redução no crescimento tumoral também se traduziu em uma sobrevivência significativamente maior para os camundongos imunizados. Estudos de infiltração celular não revelaram alterações em diversas sub-populações imunes, mas uma tendência de aumento de linfócitos T citotóxicos foi observada nos camundongos imunizados com PEP1 (bacteriófago contendo inserto). A importância deste aumento de CD8 na redução observada do crescimento tumoral foi confirmada utilizando camundongos CD8-knockout, onde a redução do crescimento tumoral previamente observada foi anulada. Foi observado um aumento de taxa CD8:CD4 nos camundongos imunizados e isto é uma indicação de ambiente tumoral citotóxico. Os ensaios de proliferação celular para testar a especificidade do antígeno dos linfócitos dos camundongos imunizados foram, no entanto, inconclusivos; da mesma forma, não pudemos alterar o padrão observado com o uso de adjuvante CpG. A utilidade da técnica de phage display também foi observada neste trabalho experimental. Trabalhos adicionais para entender o mecanismo de ação desses fagos recombinantes no controle do crescimento de tumores causados por HPV e seu potencial imuno-estimulador são necessários / The link between high-risk human papillomavirus and cervical cancer is well established. Despite the existence of prophylactic vaccines against infections by the most common types of HPV, therapeutic alternatives are limited for infections and tumors caused by these viruses. We found some homology motifs for high-risk HPV proteins during the immune-panning of a phage display library with sera from HPV-16- seropositive participants of the Ludwig-McGill cohort. After enrichment of the sequences, the recombinant bacteriophages were purified and amplified for use as immunogens. Using a prophylactic approach, we vaccinated experimentally immunocompetent mice with one of our recombinant bacteriophages using the insertless bacteriophage as a control. These mice were then challenged with TC-1 tumor cells (HPV-16 positive), and the immune responses triggered during tumor progression were evaluated. We also used a therapeutic approach where mice were first injected with tumor cells and immunized with the bacteriophage after tumor establishment. Tumor growth was monitored and tumors, spleen and lymph nodes were evaluated for the quantity and quality of the immune response. ELISA tests revealed that all vaccinated mice responded to immunization with the different bacteriophages. Tumor growth was significantly reduced in prophylactic and therapeutic immunizations, although tumor reduction was minimal when mice were treated 9 days after TC-1 cells grafting. The reduction in tumor growth also translated into a significantly greater survival for the immunized mice. Cell infiltration studies did not reveal changes in several immune subpopulations, but an upward trend in cytotoxic T lymphocytes was observed in mice immunized with PEP1 (insert-containing bacteriophage). The importance of this increase in CD8 in the observed reduction of tumor growth was confirmed using CD8-knockout mice, where the previously observed reduction of tumor growth was abolished. An increase in CD8:CD4 rate was observed in the immunized mice and this is an indication of a cytotoxic tumor environment. Cell proliferation assays to test the antigen specificity of lymphocytes from immunized mice were, however, inconclusive; likewise, we could not change the pattern observed with the use of CpG adjuvant. The usefulness of the phage display technique was also observed in this experimental work. Additional studies to understand the mechanism of action of these recombinant phages in the control of HPV tumor growth and its immunostimulatory potential are warranted
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Prevalência de infecção por HPV em jovens primíparas e fatores associados / Prevalence of HPV infection in young primiparous women and associated factors

Rama, Cristina Helena 21 July 2009 (has links)
Introdução: A infecção genital pelo papilomavírus humano (HPV) é um fator necessário para o desenvolvimento do câncer cervical. Vacinas para prevenir a infecção pelos tipos de alto risco HPV 16 e 18 foram desenvolvidas e idealmente devem ser administradas antes da exposição ao HPV através do contato sexual. As variações na prevalência do HPV e na de seus tipos específicos em diferentes populações podem influenciar as recomendações da vacina contra o HPV em diferentes locais. A vacinação após o primeiro parto poderia ser uma estratégia em potencial para atingir mulheres jovens e saudáveis, dependendo da proporção de mulheres desse grupo ainda não infectadas pelos tipos de alto risco, HPV 16 e 18. Objetivos: O objetivo principal deste estudo foi determinar a prevalência genital do DNA de tipos específicos do HPV e avaliar a associação dessa infecção com fatores de risco selecionados em mulheres após o primeiro parto, usuárias de uma maternidade pública. Métodos: Esse estudo transversal foi realizado no Hospital Maternidade Leonor Mendes de Barros (HMLMB), uma das maiores maternidades públicas da cidade de São Paulo. Durante junho de 2006 até fevereiro de 2007, 301 primíparas de 15-24 anos, cujos partos ocorreram no referido Hospital, foram incluídas no estudo entre 43 e 60 dias após o parto. Na detecção de DNA do HPV extraído das células cervicais esfoliadas foi utilizado protocolo padrão da Reação em Cadeia por Polimerase (PCR), utilizando primers PGMY09/11. Para estimar a associação da infecção por HPV com fatores de risco selecionados, foi calculada a Razão de Prevalência (RP) e o intervalo de 95% de confiança [IC]; o ajuste foi realizado utilizando-se o Modelo Linear Generalizado (MLG) com distribuição binomial e função de ligação logarítmica. Resultados: O DNA do HPV foi detectado em 58,5% (IC 95% 52,7%-64,0%) das jovens mulheres. Os tipos de HPV mais comumente encontrados foram: HPV 16, HPV 51, HPV 52, HPV 58 e HPV 71. A prevalência dos tipos de HPV incluídos nas vacinas profiláticas foi: HPV 16 - 12,0%, HPV 18 - 2,3% e HPV 6+11 - 4,3%. Os tipos de alto risco de HPV foram encontrados em 133 (44,2%) mulheres, enquanto 43 delas (14,3%) apresentaram somente tipos de HPV de baixo risco. Cento e duas mulheres (33,9%) foram positivas para apenas um tipo de HPV; entretanto, 43 (14,3%) apresentaram dois tipos, e 31 (10,3%) apresentaram três ou mais tipos virais. A análise multivariada revelou que somente a idade (p=0,020) e o hábito de fumar (p <0,001) foram fatores de risco independentemente associados com a infecção por HPV. Conclusões: Essas adolescentes e jovens primíparas apresentaram elevada prevalência de infecção genital por tipos de alto risco do HPV, mostrando que constituem um grupo de risco para o desenvolvimento de câncer cervical. Contudo, apenas 17,3% apresentaram pelo menos um dos quatro tipos virais presentes na vacina quadrivalente (HPV 6, 11, 16 ou 18), 13,3% apresentaram infecção pelos tipos HPV 16 ou 18, e somente 1,0% apresentou concomitantemente infecção por esses dois tipos virais de alto risco presentes nas vacinas. Portanto, esse estudo indica que a grande maioria dessas jovens primíparas poderia ainda se beneficiar da imunização (catch-up) contra o HPV e constitui um grupo que deve ser alvo de programas efetivos de prevenção primária e secundária para o câncer cervical / Introdution: Genital infection by human papillomavirus (HPV) is a necessary factor in the development of cervical cancer. Vaccines to prevent infection by high risk HPV genotypes 16 and 18 were developed and ideally should be administered before exposure to HPV through sexual contact. Variations in HPV prevalence in different populations and of specific HPV types could affect vaccine recommendations in different settings. Vaccination after first delivery could be a potential strategy for reaching healthy young women depending on the baseline prevalence of high risk genotypes 16 and 18 in this target group. Objectives: The main objective of this study was to determine genital type specific HPV DNA prevalence and selected risk factors associated with HPV infection after the delivery of the first child among young women in a public maternity. Methods: This cross-sectional study was carried out at Hospital Maternidade Leonor Mendes de Barros (HMLMB), one of the largest public maternity hospitals in Sao Paulo. During June 2006 to February 2007, 301 primiparous women aged 15-24 years, who gave birth at that hospital, were included in the study between 43 and 60 days after delivery. Detection of HPV DNA in cervical specimens was performed using a standardized polymerase chain reaction (PCR) protocol with PGMY09/11 primers. To estimate the association of HPV infection with selected risk factors, prevalence ratios (PR) and 95% confidence interval [CI] were estimated using a Generalized Linear Model (GLM) with binomial distribution and log link function. Results: Any HPV DNA was detected in 58.5% (95% CI 52.7%-64.0%) of the enrolled young women. Most common types of HPV found were: HPV16, HPV51, HPV52, HPV58 and HPV71. The overall prevalence of HPV types targeted by the HPV prophylactic vaccines was: HPV16 - 12.0%, HPV18 -2.3% and HPV 6+11- 4.3%. High-risk HPV types were found in 133 (44.2%) women, whereas 43 women (14.3%) had only low-risk HPV types. One hundred and two women (33.9%) were positive for one HPV type only; however, 43 (14.3%) had two types, and 31 (10.3%) had three or more types detected. The multivariate analysis revealed that only age (p for trend =0.020) and smoking habits (p <0.001) were risk factors independently associated with HPV infection. Conclusions: These adolescents and young primiparous women had high cervical HPV prevalence, suggesting that this is a high risk group for cervical cancer development. Nevertheless, 17.3% were positive to any of the four HPV types included in HPV vaccines (HPV6, 11, 16 or 18), with 13.3% positive for HPV 16 or 18, and only 1.0% of them had both vaccine related oncogenic HPV types. Thus, this study supports that the most part of young primiparous women could benefit from catch-up HPV vaccination, and represents a target group for effective primary and secondary cervical cancer prevention programs
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Données et outils pour l'optimisation de l’impact de la vaccination prophylactique contre les papillomavirus humains en France / Data and tools for improving the impact of prophylactic vaccination against human papillomavirus in France

Ben Hadj Yahia, Mohamed-Béchir 11 December 2015 (has links)
Introduction : Depuis 2007, la vaccination contre les infections à papillomavirus humains (HPV) est recommandée en complément du dépistage du cancer du col utérin (CCU). Cependant, au vu de la faible couverture vaccinale en France, l’impact épidémiologique de la vaccination est discuté, ainsi que le choix de la population cible et les moyens déployés pour son adhésion à la recommandation. Cette thèse propose des données et des outils originaux pour l’évaluation et l’optimisation de l’impact de la vaccination HPV en France. Pour les aspects quantitatifs, une modélisation de la transmission de l’infection à HPV appuyée sur des données détaillées décrivant les partenariats sexuels dans la population générale est nécessaire. L’exploration du lien potentiel entre la participation au dépistage du CCU des femmes précaires et leur choix d’administrer le vaccin HPV à leurs filles, l’appréciation de l’acceptabilité de la vaccination à partir des réseaux sociaux, et l’évaluation médico-économique de la pertinence de l’extension de la vaccination aux hommes, sont déterminants pour parfaire le ciblage des populations à atteindre.Méthodes : Nous avons développé une plateforme de modélisation destinée à l'étude des contacts sexuels et de la dynamique de transmission des infections par les HPV à partir des données de l’enquête Contexte de la Sexualité en France. Grâce à des modèles de mélange de lois, nous avons identifié des classes latentes d’activité sexuelle, permettant de définir des profils à risque d’infections sexuellement transmissibles. Ensuite, nous avons interrogé les femmes consultant au sein du Centre de Prévention et d’Éducation pour la Santé de Lille, ayant au moins une fille éligible à la vaccination HPV, sur leurs attitudes vis-à-vis du dépistage du CCU et de la vaccination. Puis, nous avons analysé les opinions exprimées par les internautes sur le forum en ligne d’un site d’information en santé, concernant la sécurité, l’efficacité et la perception du vaccin HPV. Enfin, nous avons réalisé une revue systématique des études médico-économiques relatives à l’extension de la vaccination HPV aux hommes.Résultats : Les simulations sur la plateforme de modélisation ont permis de reproduire les données de prévalence des infections à HPV mais les résultats restent sensibles aux hypothèses sur les comportements sexuels qui présentent des incohérences entre les hommes et les femmes. Cinq classes latentes d’activité sexuelle ont été identifiées pour les hommes ainsi que pour les femmes. Le cluster correspondant au niveau d’activité sexuelle le plus élevé représente 3,3% chez les femmes et 4,8% chez les hommes. Par ailleurs, le statut vaccinal des filles ne diffère pas selon le profil de dépistage de leur mère. L’argument majoritairement rapporté par les mères pour justifier la non-vaccination de leurs filles concerne le manque d’information, surtout parmi celles qui ne se dépistent pas. De plus, les opinions négatives, exprimées sur le forum de discussion en ligne, sont passées de 28,6 % des avis exprimés en 2006 à 42,2 % en 2013. Les arguments avancés par les « anti-vaccinaux » concernent la sécurité du vaccin et la perception de la vaccination. Enfin, les modèles médico-économiques montrent que l’extension de la vaccination aux hommes est très rarement une stratégie coût-efficace. Néanmoins, la vaccination ciblée des homosexuels masculins semble être la stratégie optimale du point de vue éthique et médico-économique.Discussion : La plateforme de modélisation des contacts sexuels constitue le socle de l’évaluation de l’impact de la vaccination HPV. La surveillance des forums de discussion en ligne permet le monitoring de l’acceptabilité de la vaccination et le ciblage des actions d’information. L’optimisation de couverture vaccinale nécessite la mise en place d’un programme organisé de vaccination des jeunes filles. À défaut d’une implémentation en milieu scolaire, les centres de prévention offrent une alternative intéressante. / Introduction: Since 2007, prophylactic vaccination against human papillomavirus (HPV) has been recommended in addition to cervical screening in French women. However, given the low vaccine coverage in France, the epidemiological impact of the vaccination is debated, as well as the choice of the target population and the means to ensure compliance with the recommendation. This doctoral thesis provides original data and tools for the evaluation and the improvement of the impact of HPV vaccination in France. For quantitative aspects, modelling HPV transmission based on the best data describing sexual partnerships in the general population is essential. The investigation of potential links between participation to cervical screening of deprived women and their choice of vaccinating their daughters, the appraisal of vaccine acceptability through social media and the cost-effectiveness evaluation of the relevance of extending the HPV vaccination program to include males are key elements to improve the focus on targeted populations.Methods: We developed a modelling platform to study the dynamics of HPV transmission, using data from Social Context of Sexuality, the latest national French sexual behavior study. Using finite mixture models, we identified latent classes of sexual activity to define profiles of partner acquisition with age, likely to have different risks of sexually transmitted infections. Then, we asked women attending the Centre for Preventive Medicine and Health Education of Lille, who had at least a daughter eligible for HPV vaccination, about their attitudes towards cervical screening and HPV vaccination. Next, we explored sentiments about HPV vaccine safety, efficacy and perceptions, spontaneously expressed by web users on the online discussion forum of a French-speaking health information website. Finally, we performed a systematic review of the cost-effectiveness studies about extending HPV vaccination to include males.Results: Simulations from the modelling platform reproduced HPV infection prevalence observed in France. Nevertheless, results were sensitive to assumptions about sexual behavior, with discrepancies between men and women. Five latent classes of sexual activity were identified in men and in women. The cluster describing the highest level of sexual behavior represents 3.3% in women and 4.8% in men. Besides, daughters’ vaccination profile did not differ with their mothers’ profile of participation to cervical screening. The main reason for not vaccinating their daughters reported by mothers was lack of information, especially for those non-compliant with cervical screening recommendations. Moreover, negative sentiments, reported by the health website forum, evolved from 28.6% of total opinions in 2006 to 42.2% in 2013. The arguments expressed by “anti-vaccine” postings involved most often vaccine safety and negative vaccine perceptions. Finally, cost-effectiveness analyses show that extending the HPV vaccination program to include males is rarely found to be a cost-effective strategy. Nevertheless, the targeted vaccination of men having sex with men seems to be the best strategy from ethical and cost-effectiveness points of view.Discussion: The modelling platform of sexual contacts represents the basis of the evaluation of HPV vaccination impact. The surveillance of online forums enables the monitoring of vaccine acceptability and hence the targeting of preventive messages. Improving the HPV vaccine coverage requires offering girls and young women an organized vaccination program. In the lack of a school-based vaccination program, Centres for Preventive Medicine and Health Education offer an interesting alternative.
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Identification et caractérisation d'un domaine de transactivation dans l’hélicase E1 des papillomavirus humains

Morin, Geneviève 04 1900 (has links)
Les papillomavirus sont des virus à ADN qui infectent la peau et les muqueuses. Ils causent des verrues et peuvent aussi mener au développement de cancers, dont le cancer du col de l’utérus. La réplication de leur génome nécessite deux protéines virales : l’hélicase E1 et le facteur de transcription E2, qui recrute E1 à l’origine de réplication virale. Pour faciliter l’étude de la réplication du génome viral, un essai quantitatif et à haut débit basé sur l’expression de la luciférase a été développé. Parallèlement, un domaine de transactivation a été identifié dans la région régulatrice N-terminale de la protéine E1. La caractérisation de ce domaine a montré que son intégrité est importante pour la réplication de l’ADN. Cette étude suggère que le domaine de transactivation de E1 est une région protéique intrinsèquement désordonnée qui permet la régulation de la réplication du génome viral par son interaction avec diverses protéines. / Papillomaviruses are small DNA viruses that infect skin and mucosa. They cause warts and can also lead to the development of cancers, including cervical cancer. Replication of their genome requires two viral proteins: the E1 helicase and the E2 transcription factor, which recruits E1 to the viral origin of replication. To facilitate the study of viral genome replication, a quantitative and high-throughput assay based on luciferase expression has been developed. In parallel, a transactivation domain has been identified in the N-terminal regulatory region of the E1 protein. Characterization of this domain showed that its integrity is important for DNA replication. This study suggests that the E1 transactivation domain is an intrinsically unstructured protein region that allows regulation of viral genome replication by its interaction with diverse proteins.
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Parenting practices, acculturation and Hispanic youth's sexual health.

Morales-Campos, Daisy Y. Markham, Christine M., Fernandez, Maria E., Peskin, Melissa F. Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 70-07, Section: B, page: 4120. Advisers: Christine M. Markham; Maria E. Fernanez. Includes bibliographical references.

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