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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.
1

An Assessment of Selected Factors Associated with HPV Vaccination Completion among the African American Adolescents in United States: 2012 National Immunization Survey - Teen

Sahu, Vaishali 12 August 2014 (has links)
Background: Human Papillomavirus is the most common STI in United States and is most prevalent among the adolescents and young adults. HPV causes cervical, anal, vulvar, vaginal, penile, oropharyngeal cancers and ano-genital warts. Certain populations are found to be at higher risk such as African Americans. 3 doses of HPV vaccine are recommended to adolescents before sexual debut to immunize against HPV. The purpose of this study was to assess the factors associated with the completion of 3 dose HPV vaccination series particularly among the African American adolescents. Methods: National Immunization Survey – Teen 2012 data was used to assess the association of selected factors with the completion of 3 dose HPV vaccination series among the African American adolescents. Univariate and multivariate binary logistic regression was conducted. Results: Factors, gender, age and maternal education are associated with the completion of HPV vaccination series among the African American adolescents. The Black females are 5 times more likely to complete the HPV vaccination than males. The 15 year olds are thrice more likely to complete the HPV vaccination than 13 year olds. Adolescents with maternal education higher than high school are twice more likely to complete the HPV vaccination series. Conclusion: Among the African American adolescents, socio-demographic factors influence the completion of HPV vaccine series. This study provides a direction to public health practices to focus on Black male adolescents and subpopulations with low maternal education to improve HPV vaccination in US.
2

College Students' HPV Knowledge and Intention to be HPV Vaccinated

Johnson, Chandrika 01 December 2014 (has links)
Combating HPV infection in males is a significant public health issue. In addition to the number of HPV-related cancers that develop each year, Palefsky (2007) reported that "HPV infection of men is of great importance given that sexual transmission is the primary mode of spread to women" (p. 261). In recent years, the development of the HPV vaccine has spurred controversy over whether or not males as well as females should obtain the vaccine against this disease. The purpose of this study was to examine male college students' intention to be HPV vaccinated and their HPV knowledge, attitudes, subjective norms, and perceived behavioral control towards the vaccination. A descriptive, correlational, cross-sectioned research design was employed. Two hundred and eight (208) male college students at a mid-sized public university participated in the study and completed an in-class questionnaire. The results of the descriptive statistics showed that, on average, the sample of 208 male college students had correct responses on only half of the 15 questions regarding knowledge about HPV based on the mean scores. Respondents had positive attitudes towards HPV vaccination, greater sense of control over being HPV vaccinated, and favorable intention to be HPV vaccinated. Subjective norms and perceived behavioral control were significant predictors of male college students' behavioral intention to be HPV vaccinated. Subjective norms and perceived behavioral control had a positive influence on male college students' behavioral intention to be HPV vaccinated. Lastly, male college students' level of HPV knowledge was not significantly correlated to their behavioral intention to be HPV vaccinated
3

Análise da frequência de Papilomavírus humano e Chlamydia trachomatis em amostras anais de pacientes com lesão cervical

Silva, Keilla Maria Paz e 25 February 2014 (has links)
Submitted by Amanda Silva (amanda.osilva2@ufpe.br) on 2015-03-11T13:27:51Z No. of bitstreams: 2 DISSERTAÇÃO Keilla Maria Silva.pdf: 4228154 bytes, checksum: ea3da547f9bdeacfacd07ad7ced6d809 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-11T13:27:51Z (GMT). No. of bitstreams: 2 DISSERTAÇÃO Keilla Maria Silva.pdf: 4228154 bytes, checksum: ea3da547f9bdeacfacd07ad7ced6d809 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2014-02-25 / CNPq / O Papilomavírus Humano (HPV) é um agente sexualmente transmissível que se destaca por infectar o trato anogenital, e devido à sua associação etiológica com uma grande variedade de carcinomas, encontra-se entre as mais importantes infecções sexualmente transmissíveis (IST) da atualidade. Acredita-se que a presença do vírus da imunodeficiência humana (HIV) e da Chlamydia trachomatis parecem favorecer a infectividade viral, proporcionando o surgimento de lesões que podem levar ao câncer. Desta forma, o presente trabalho teve por objetivo avaliar os genótipos do HPV presentes em amostras cervicais e anais, correlacionando com a infecção por Chlamydia trachomatis. Realizou-se um estudo incluindo 73 mulheres com idade entre 17 e 65 anos, atendidas no Hospital das Clínicas de Pernambuco (HC/UFPE) entre novembro de 2010 e fevereiro de 2013. As amostras foram obtidas e a extração do DNA foi realizada através de kits específicos. Posteriormente, os genótipos do HPV foram determinados pelo PapilloCheck® (GreinerBio-One) e a identificação da Chlamydia trachomatis por PCR em Tempo-Real. A prevalência do HPV no canal anal foi de 83,6%, estando associado com história de intercurso anal (p=0.0295) e infecção por HIV (p=0.0104). Infecção múltipla por HPV foi observada em 50,8% das pacientes, sendo o HPV44 o mais comum. Nos grupos HIV-positivo e HIV-negativo, o genótipo de alto risco mais frequente foi o HPV16, enquanto que HPV44 e o HPV43 foram os genótipos de baixo risco mais encontrados, respectivamente. A taxa de concordância entre os genótipos de HPV cervical e anal chegou a 52%. Apenas um paciente apresentou infecção por Chlamydia trachomatis em canal anal. Os resultados sugerem que o canal anal pode ter participação na infecção cervical funcionando como reservatório do vírus. Desta forma, o rastreamento dessas pacientes no serviço público de saúde pode favorecer um diagnóstico precoce, auxiliando os médicos no acompanhamento e prevenindo a evolução da infecção, principalmente em pacientes HIV-positivas.
4

Contribuição para o estudo da memória de reconhecimento social em ratos / Contributions to the study of social recognition memory in rats

Moura, Paula Jaqueline de 21 July 2008 (has links)
O paradigma intruso-residente vem sendo intensamente empregado em estudos para avaliar a memória de reconhecimento social em roedores. Tipicamente, ratos adultos, denominados residentes, são expostos a dois encontros sucessivos, de 5 minutos cada, com um mesmo rato juvenil ou com ratos juvenis diferentes, denominados intrusos; o intervalo de tempo entre encontros é 30 minutos. A quantidade de comportamentos sociais do residente (no segundo encontro) em relação a um intruso familiar é substancialmente menor do que o observado no primeiro encontro, o que não ocorre quando o segundo encontro envolve um juvenil novo; esse resultado caracteriza a memoria de reconhecimento social. Se o intervalo de tempo entre os encontros é aumentado para 60 minutos, a redução da investigação social do intruso familiar por parte do residente desaparece, levando à conclusão de que a memória de reconhecimento social seria um mecanismo para retenção temporária de informações. O objetivo central do presente trabalho foi contribuir para o entendimento da memória de reconhecimento social em ratos. Foram realizados três experimentos. No primeiro experimento avaliou-se se a expressão de comportamentos sociais e também da memória de reconhecimento social estão sujeitos à modulação temporal. No segundo experimento avaliou-se em que extensão o aumento do tempo de exposição ao intruso durante o primeiro encontro resulta num aumento da duração da memoria de reconhecimento social. No terceiro experimento avaliou-se se um procedimento de rotina na maioria dos laboratorios, o transporte dos animais da sala de experimentos para o biotério, interfere na memória de reconhecimento social, quando realizado 0,5 ou 6 horas após o primeiro encontro. Os resultados mostraram que (1) a expressão de comportamentos sociais e a memória de reconhecimento social estão sujeitos à modulação temporal, sendo mais intensos quando os testes são realizados na fase inativa (Capítulo 2), de modo que este fator deve ser levado em consideração quando do planejamento de experimentos envolvendo sociabilidade, (2) o aumento da duração do primeiro encontro para 2 horas ou mais revelou uma memória de reconhecimento social que dura pelo menos 24 horas (Capítulo 3), permitindo questionar que se trate de um dispositivo de curta duração, e (3) o transporte dos animais para o biotério 0,5 horas, mas não 6 horas, depois do primeiro encontro, prejudica a memória de reconhecimento social (Capítulo 4), indicando que se deve estar atento às rotinas laboratoriais pois as mesmas podem interferir no desempenho dos animais em testes de memória. Em associação com essas relevantes observações experimentais, foram propostas estratégias de análise dos dados gerados com esse tipo de experimentação e também discussões conceituais sobre a caracterização da memória de reconhecimento social, que contribuem marcadamente para essa área de estudos. / The intruder-resident paradigm has been extensively employed in studies of social recognition memory in rodents. Typically, adult rats, named residents, are exposed to two 5-min successive encounters with the same juvenile intruder or with two different juveniles; the time interval between the encounters is 30 min. The amount of social behaviors exhibited by the resident rats towards the same intruder juvenile in the second encounter is substantially smaller when compared to both that seen in the first encounter and that seen towards a different juvenile; these results characterize social recognition memory. When the time interval between encounters is increased to 60 min, that reduction of the investigation towards the familiar juvenile intruder vanishes, which is seen as evidence that social recognition memory corresponds to a short-term memory mechanism. The aim of this study was to contribute for our understanding of social recognition memory in rats. Three experiments were run. The first experiment evaluated to which extent both social behaviors and social recognition memory are influenced by temporal phase effects. The second experiment evaluated to which extent the increase in the duration of the first encounter renders social recognition memory longer. The third experiment evaluated to which extent the transportation of the resident rats from the experimental room to the animal facilities either 0.5 or 6 hours after the first encounter, interferes with social recognition memory. The results showed that (1) the expression of social behaviors and of the social recognition memory are modulated temporal phase effects, being stronger when animals are tested in their inactive phase (Chapter 2); thus, this aspect has to be considered in studies on sociability, (2) the increase of the first encounter duration for 2 hours or longer renders social recognition memory to last at least 24 hours (Chapter 3); this allows to question that social recognition memory corresponds to a short-term memory mechanism, and (3) transportation of the resident rats to the animal facilities 0.5, but not 6 hours, after the end of the first encounter disrupts social recognition memory (Chapter 4), indicating that one has to be cautious about usual laboratory routines, because they may interfere with performance of the memory tasks when executed a short time after training the animals.Associated with these relevant experimental observations, these studies allowed proposing novel strategies for data analysis and discussing conceptual issues about the characterization of social recognition memory that give a substantial contribution for this area.
5

Estudo in vitro sobre a interação celular e vias endocíticas de papilomavírus humano (HPV) em leucócitos do sangue periférico. / In vitro study on the interaction of human papillomavirus in cell from peripheral blood leukocytes.

Szulczewski, Vívian 05 May 2009 (has links)
O papilomavírus humano (HPV) é o principal agente etiológico do câncer cervical e anogenital, sendo o HPV16 e o HPV18 os vírus de alto risco. Estudos recentes evidenciaram que além da transmissão sexual do HPV, há outras formas de contágio. Entretanto, a dificuldade na obtenção de quantidades viáveis do tipo selvagem ou mutante do HPV tem limitado em muito os estudos de diversos aspectos da biologia do papilomavírus. Este estudo investigou a possibilidade de o HPV infectar células leucocitárias do sangue periférico humano. Concluímos que as VLPs L1L2 do HPV16 podem utilizar a via endocítica do ferro mediada por clatrina, através do complexo VLPs-Transferrina-Receptor de Transferrina, permanecendo de forma latente em leucócitos. Esta porta de entrada oportunista poderia explicar a propagação crescente e alarmante deste agravo à saúde humana, motivo de preocupação nos sistemas mundiais de saúde pública. Este trabalho demonstrou pela primeira vez a internalização de VLPs L1L2 do HPV16 em leucócitos do sangue periférico humano. / Human papillomavirus (HPV) is the primary etiologic agent of anogenital and cervical cancer, caused mainly by the high-risk HPV16 and HPV18 viruses. Recent studies revealed that besides the sexual transmission of HPV, there are other forms of contagion. However, the difficulty in obtaining quantities of viable wild-type or mutant of HPV constitutes a limiting factor in the studies of various aspects of the biology of human papillomavirus. This study investigated the possibility of HPV infect the cells of human peripheral blood leukocytes. We conclude that the VLPs L1L2 of HPV16 may use the iron endocytic pathway clathrin-mediated through the complex VLPs-Transferrin-Transferrin Receptor and remained so latent in leukocytes. This port of entry opportunist could explain the growing and alarming spread of this disease to human health, cause for concern in the global public health. This study showed for the first time the internalization of VLPs L1L2 of HPV16 in human peripheral blood leukocytes.
6

Contribuição para o estudo da memória de reconhecimento social em ratos / Contributions to the study of social recognition memory in rats

Paula Jaqueline de Moura 21 July 2008 (has links)
O paradigma intruso-residente vem sendo intensamente empregado em estudos para avaliar a memória de reconhecimento social em roedores. Tipicamente, ratos adultos, denominados residentes, são expostos a dois encontros sucessivos, de 5 minutos cada, com um mesmo rato juvenil ou com ratos juvenis diferentes, denominados intrusos; o intervalo de tempo entre encontros é 30 minutos. A quantidade de comportamentos sociais do residente (no segundo encontro) em relação a um intruso familiar é substancialmente menor do que o observado no primeiro encontro, o que não ocorre quando o segundo encontro envolve um juvenil novo; esse resultado caracteriza a memoria de reconhecimento social. Se o intervalo de tempo entre os encontros é aumentado para 60 minutos, a redução da investigação social do intruso familiar por parte do residente desaparece, levando à conclusão de que a memória de reconhecimento social seria um mecanismo para retenção temporária de informações. O objetivo central do presente trabalho foi contribuir para o entendimento da memória de reconhecimento social em ratos. Foram realizados três experimentos. No primeiro experimento avaliou-se se a expressão de comportamentos sociais e também da memória de reconhecimento social estão sujeitos à modulação temporal. No segundo experimento avaliou-se em que extensão o aumento do tempo de exposição ao intruso durante o primeiro encontro resulta num aumento da duração da memoria de reconhecimento social. No terceiro experimento avaliou-se se um procedimento de rotina na maioria dos laboratorios, o transporte dos animais da sala de experimentos para o biotério, interfere na memória de reconhecimento social, quando realizado 0,5 ou 6 horas após o primeiro encontro. Os resultados mostraram que (1) a expressão de comportamentos sociais e a memória de reconhecimento social estão sujeitos à modulação temporal, sendo mais intensos quando os testes são realizados na fase inativa (Capítulo 2), de modo que este fator deve ser levado em consideração quando do planejamento de experimentos envolvendo sociabilidade, (2) o aumento da duração do primeiro encontro para 2 horas ou mais revelou uma memória de reconhecimento social que dura pelo menos 24 horas (Capítulo 3), permitindo questionar que se trate de um dispositivo de curta duração, e (3) o transporte dos animais para o biotério 0,5 horas, mas não 6 horas, depois do primeiro encontro, prejudica a memória de reconhecimento social (Capítulo 4), indicando que se deve estar atento às rotinas laboratoriais pois as mesmas podem interferir no desempenho dos animais em testes de memória. Em associação com essas relevantes observações experimentais, foram propostas estratégias de análise dos dados gerados com esse tipo de experimentação e também discussões conceituais sobre a caracterização da memória de reconhecimento social, que contribuem marcadamente para essa área de estudos. / The intruder-resident paradigm has been extensively employed in studies of social recognition memory in rodents. Typically, adult rats, named residents, are exposed to two 5-min successive encounters with the same juvenile intruder or with two different juveniles; the time interval between the encounters is 30 min. The amount of social behaviors exhibited by the resident rats towards the same intruder juvenile in the second encounter is substantially smaller when compared to both that seen in the first encounter and that seen towards a different juvenile; these results characterize social recognition memory. When the time interval between encounters is increased to 60 min, that reduction of the investigation towards the familiar juvenile intruder vanishes, which is seen as evidence that social recognition memory corresponds to a short-term memory mechanism. The aim of this study was to contribute for our understanding of social recognition memory in rats. Three experiments were run. The first experiment evaluated to which extent both social behaviors and social recognition memory are influenced by temporal phase effects. The second experiment evaluated to which extent the increase in the duration of the first encounter renders social recognition memory longer. The third experiment evaluated to which extent the transportation of the resident rats from the experimental room to the animal facilities either 0.5 or 6 hours after the first encounter, interferes with social recognition memory. The results showed that (1) the expression of social behaviors and of the social recognition memory are modulated temporal phase effects, being stronger when animals are tested in their inactive phase (Chapter 2); thus, this aspect has to be considered in studies on sociability, (2) the increase of the first encounter duration for 2 hours or longer renders social recognition memory to last at least 24 hours (Chapter 3); this allows to question that social recognition memory corresponds to a short-term memory mechanism, and (3) transportation of the resident rats to the animal facilities 0.5, but not 6 hours, after the end of the first encounter disrupts social recognition memory (Chapter 4), indicating that one has to be cautious about usual laboratory routines, because they may interfere with performance of the memory tasks when executed a short time after training the animals.Associated with these relevant experimental observations, these studies allowed proposing novel strategies for data analysis and discussing conceptual issues about the characterization of social recognition memory that give a substantial contribution for this area.
7

Estudo in vitro sobre a interação celular e vias endocíticas de papilomavírus humano (HPV) em leucócitos do sangue periférico. / In vitro study on the interaction of human papillomavirus in cell from peripheral blood leukocytes.

Vívian Szulczewski 05 May 2009 (has links)
O papilomavírus humano (HPV) é o principal agente etiológico do câncer cervical e anogenital, sendo o HPV16 e o HPV18 os vírus de alto risco. Estudos recentes evidenciaram que além da transmissão sexual do HPV, há outras formas de contágio. Entretanto, a dificuldade na obtenção de quantidades viáveis do tipo selvagem ou mutante do HPV tem limitado em muito os estudos de diversos aspectos da biologia do papilomavírus. Este estudo investigou a possibilidade de o HPV infectar células leucocitárias do sangue periférico humano. Concluímos que as VLPs L1L2 do HPV16 podem utilizar a via endocítica do ferro mediada por clatrina, através do complexo VLPs-Transferrina-Receptor de Transferrina, permanecendo de forma latente em leucócitos. Esta porta de entrada oportunista poderia explicar a propagação crescente e alarmante deste agravo à saúde humana, motivo de preocupação nos sistemas mundiais de saúde pública. Este trabalho demonstrou pela primeira vez a internalização de VLPs L1L2 do HPV16 em leucócitos do sangue periférico humano. / Human papillomavirus (HPV) is the primary etiologic agent of anogenital and cervical cancer, caused mainly by the high-risk HPV16 and HPV18 viruses. Recent studies revealed that besides the sexual transmission of HPV, there are other forms of contagion. However, the difficulty in obtaining quantities of viable wild-type or mutant of HPV constitutes a limiting factor in the studies of various aspects of the biology of human papillomavirus. This study investigated the possibility of HPV infect the cells of human peripheral blood leukocytes. We conclude that the VLPs L1L2 of HPV16 may use the iron endocytic pathway clathrin-mediated through the complex VLPs-Transferrin-Transferrin Receptor and remained so latent in leukocytes. This port of entry opportunist could explain the growing and alarming spread of this disease to human health, cause for concern in the global public health. This study showed for the first time the internalization of VLPs L1L2 of HPV16 in human peripheral blood leukocytes.
8

Sekreční projevy v anogenitální oblasti u samic kočkodana Brazzova (Cercopithecus neglectus) / Secretory symptoms of the anogenital section in female De Brazza's monkey (\kur{Cercopithecus neglectus})

VOLÁK, Daniel January 2015 (has links)
The thesis is focused on the unprecedented phenomenon namelysecretory activity in female De Brazza´s monkey (Cercopithecus neglectus). The work gives a comprehensive overview of the life of monkeys. There is also a comparison with other related species of monkeys that live in similar or even identical conditions. It analyzes the olfactory and visual communication, for which it may have color and density of the discharge in the anogenital section key role. It compares discolouring outlet discharge of individual female in the experimental part.
9

Analýza miRNA u nádorů asociovaných s lidskými papilomaviry / Analysis of miRNAs in HPV-associated carcinomas

Pagáčová, Lucie January 2020 (has links)
Papillomaviruses are small DNA viruses that are associated with the induction of epithelial tumors. HPV is an important infectious agent causing almost 100 % of cervical tumors but it can also cause tumors in other anogenital and head and neck locations in both men and women. Active HPV infection induces changes in miRNA expression that contribute to the tumor formation and progression. It is already known that papillomaviruses do not encode their own viral miRNAs but they affect the expression of cellular miRNAs. In my thesis I have in selected epithelial tumors (vulva, cervix, anus and tonsils) determined their etiology and analyzed the presence of miRNAs in tissues by next generation sequencing. From these data I determined the expression profiles of deregulated miRNAs in tumors relation to healthy tissues of corresponding location. Even though, sufficient number of samples was analyzed, it was not possible to detect HPV-core miRNA common to all analyzed HPV-induced tumors due to the absence of statistically relevant differentially expressed miRNAs in HPV positive vulvar tumors. Among the tumors of the other sites I found an overlap in three miRNAs. One of these miRNAs (miR-139-5p) and another one (miR-9-5p) which I have selected based on the study of other published data, were used for...
10

Analyse de la distribution des génotypes du virus du papillome humain dans les néoplasies anogénitales et de la tête et du cou en Afrique comparativement au reste du monde

Ndiaye, Cathy 08 1900 (has links)
Le virus du papillome humain (HPV) est l’infection sexuellement transmise la plus fréquente au monde. Plusieurs études ont établi son implication dans l’étiologie de pratiquement tous les cancers du col de l’utérus, une maladie qui constitue un problème de santé majeur dans les pays pauvres. Le HPV est également responsable de 90% des cancers de l’anus, 40-50% des cancers du pénis, de la vulve et du vagin, et 30% des cancers de la tête et du cou. L’objectif général de cette thèse est de combler les lacunes relatives aux connaissances sur la distribution génotypique du HPV dans les lésions néoplasiques cervicales utérines et de la tête et du cou, plus particulièrement en Afrique. Les objectifs spécifiques sont les suivants: 1) analyser la distribution génotypique du HPV dans les cancers du col de l’utérus et faire une analyse comparative de cette distribution dans cinq pays africains en fonction de la prévalence du VIH; 2) évaluer la présence du HPV dans les cancers de la tête et du cou au Sénégal; 3) faire une revue de la littérature et une méta-analyse sur la distribution du HPV dans les cancers de la tête et du cou dans toutes les régions du monde. Pour le premier et le second objectifs, qui découlent d’un large projet international coordonné par l’Institut Catalan d’Oncologie pour l’Organisation Mondiale de la Santé (OMS), une étude transversale multicentrique a été menée au Mali et au Sénégal pour collecter des blocs de paraffine de patientes diagnostiquées entre 2001 et 2010 du cancer invasif du col et des cancers de la tête et du cou. Pour le troisième objectif, une revue exhaustive de la littérature a permis d’identifier tous les articles qui ont été publiés sur les cancers de la tête et du cou dans tous les pays du monde et d’effectuer une méta-analyse sur la prévalence de l’ADN du HPV selon le site du cancer et la région géographique. Notre analyse montre que les principaux types de HPV ciblés dans les vaccins prophylactiques (HPV16/18) représentent la majorité des types de HPV détectés dans le cancer invasif du col de l’utérus en Afrique subsaharienne. Par contre, le HPV45 vient au second rang dans certains pays d’Afrique, dont le Mali et le Sénégal. Nos données suggèrent également que le VIH aurait un rôle dans la contribution relative du HPV18 et HPV45 dans le développement du cancer du col de l’utérus. Au Sénégal, notre étude montre que la prévalence du HPV dans les cancers de la tête et du cou est très faible et ne semble pas jouer un rôle important dans l’oncogenèse. Finalement, la méta-analyse a mesuré la prévalence des HPV dans les cancers de la cavité orale, de l’oropharynx, du larynx et de l’hypopharynx, et confirme l’importante contribution relative du HPV16 dans ces cancers. Globalement, cette thèse permet de mieux comprendre l’impact potentiel des vaccins prophylactiques sur l’incidence des cancers associés au HPV. / Human papillomavirus (HPV) infection is the most common sexually transmitted infection worldwide. Several studies have shown its involvement in the etiology of virtually all cancers of the cervix, which is a major health problem in poor countries. HPV is also responsible for 90% of anal cancers, 40-50% of penile, vulvar and vaginal cancers, and 30% of head and neck cancers. The overall objective of this thesis is to fill the gaps in knowledge on the genotype distribution of HPV in anogenital and head and neck neoplasia, especially in sub-Saharan Africa. The specific objectives are to: 1) analyze HPV genotype distribution in cervical cancer and compare this distribution in five African countries according to HIV prevalence; 2) evaluate the presence of HPV in cancers of the head and neck in Senegal; 3) review the literature on the distribution of HPV in cancers of the head and neck in all regions of the world and perform a meta-analysis. For the first and second objectives, which were derived from a larger international project coordinated by the Catalan Institute of Oncology for the World Health Organization (WHO), a cross-sectional multicentric study was conducted to collect paraffin-embedded blocks of invasive cervical cancer and head and neck cancer diagnosed between 2001 and 2010 in Mali and Senegal. For the third objective, a comprehensive search of the literature was conducted to identify all articles published to date on head and neck cancer. A meta-analysis was performed to estimate the prevalence of HPV DNA according to cancer site and geographical region. Our analysis shows that the main HPV types targeted in the prophylactic vaccines (HPV16/18) accounted for the majority of the HPV types found in invasive cervical cancer in sub-Saharan Africa. Our data also suggests that HIV may play a role in the contribution of HPV18 and HPV45 to the development of cervical cancer. However, HPV45 ranks second in many African countries, notably in Mali and Senegal. In Senegal, our study shows that HPV DNA prevalence in head and neck cancer is very low and is not importantly involved in the oncogenesis. Finally, the meta-analysis measured the prevalence of HPV in cancers of the oral cavity, oropharynx, larynx and hypopharynx, and confirmed the significant relative contribution of HPV16 in these cancers. Overall, this thesis contributes to a better understanding of the potential impact of HPV prophylactic vaccines on the incidence of HPV-associated cancers.

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