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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.
81

Human Papillomavirus: Identifying Vaccination Rates, Barriers, and Information Gathering among College Women Ages 18-26

Cohen, Timmerie 25 April 2013 (has links)
This dissertation examines vaccination rates for Human Papillomavirus (HPV) among college women 18-26 years of age who participated in the American College Health Association’s National College Assessment (ACHA-NCHA). Utilizing secondary data, this research sought to report HPV vaccination rates among a racially diverse population and to identify potential barriers to vaccination. The ACHA-NCHA survey provided a large sample size (N=68,193) in which to perform a binary logistic regression analysis. Demographic characteristics were analyzed as potential barriers to HPV vaccination. Additionally, lack of certain health behaviors were explored as potential barriers to HPV vaccination. In this study, White/non-Hispanic women had a higher HPV vaccination rate when compared to minority women. The binary regression analysis demonstrated that minority women were less likely to receive the HPV vaccine. Furthermore, it was determined that as the age of the respondents increased, the likelihood of receiving the vaccine decreased. Health behaviors that were predictive of receiving the HPV vaccine included receiving the Hepatitis B and Influenza vaccine, number of sexual partners and receiving sexually transmitted disease information. Women who received a gynecological exam were almost twice as likely to receive the vaccine, as were women who had parental health insurance coverage. One aim of The Affordable Care Act (2010) is to decrease disparities in health care. Drawing attention to potential barriers to HPV vaccination allows policy makers to make informed decisions regarding future activities to reduce disparities. Health promotion activities should be targeted to specific populations in an effort to increase HPV vaccination rates.
82

Potencial vacinal de proteínas recombinantes do capsídeo de papilomavírus humano. / Vaccine potential of recombinant proteins of human papillomavirus capsid.

Sakauchi, Dirce 04 February 2016 (has links)
O câncer cervical é a consequência mais séria da infecção por Papilomavírus humano - HPV, constituindo uma das principais causas de morte entre mulheres no mundo, remetendo a um importante desafio para a saúde pública mundial. Desenvolvemos a produção de VLPs contendo as proteínas L1 e L2 de HPV16, utilizando células epiteliais humanas 293-F em suspensão e em meio isento de soro fetal bovino. As células possuem metabolismo intenso, adequado para a expressão de proteínas heterólogas. Apresentam vantagens como a facilidade de cultivo, transfecção e ocorrência de processos como a glicosilação de proteínas, fosforilação, formação de pontes dissulfeto e outras modificações pós-traducionais essenciais para a função das proteínas, facilitando a produção similar às condições in vivo. O sistema de produção de VLPs L1L2 de HPV16 foi estabelecido de maneira eficiente, em células epiteliais humanas em suspensão e com resultados promissores, podendo contribuir para o desenvolvimento de uma vacina profilática de amplo espectro de proteção, com custo reduzido de produção. / Cervical cancer is the most serious consequence of infection by human papillomavirus - HPV, constituting one of the leading causes of death among women worldwide that points to a major challenge to global public health. We have developed the production of VLPs containing L1 and L2 proteins of HPV16, using human epithelial cells 293-F suspended in medium without fetal bovine serum. The cells have intense metabolism, suitable for expressing heterologous proteins. Present advantages such as ease of culture, transfection and occurrence of processes such as protein glycosylation, phosphorylation, formation of disulfide bonds and other essential post-translational modifications to protein function, facilitating the production similar to the conditions in vivo. The VLPs L1L2 of HPV16 production system was established efficiently in human epithelial cells in suspension and with promising results, which may contribute to the development of a prophylactic vaccine broad protection spectrum with reduced production cost.
83

Characterization of the Nuclear Export Signal of Human Papillomavirus 16 L2 Minor Capsid Protein

Halista, Courtney Ellen January 2011 (has links)
Thesis advisor: Junona Moroianu / The L2 minor capsid protein of human papillomavirus is one of two structural proteins that comprise the icosahedral shell. Two potential, leucine-rich nuclear export signals (NESs) had been identified in the HPV16 L2 sequence, one in the n-terminus (51MGVFFGGLGI60) and one in the c-terminus (462LPYFFDSVSL471). DNA primers for mutant L2 proteins were designed to specifically target these two potential NES regions. Two primers had mutations in the n-terminal located NES (nNES), while the other two primers had mutations in the c-terminal NES (cNES). L2 nuclear retention mutants, RR297AA (“MS4”) and RTR313AAA (“MS5”), served as the templates for these NES mutations. Using mutagenesis, the desired secondary mutations were introduced into the mutant L2 genes in order to create four, distinct mutants: RR297AA + P463_ (“MS4 T1”), RR297AA + V469_ (“MS4 T2), RTR313AAA + P463_ (“MS5 T1”), and RTR313AAA + V469_ (“MS5 T2”). In contrast to the pancellular localization of the MS4 and MS5 L2 mutants, the “MS4 T1,” “MS4 T2,” “MS5 T1”, and “MS5 T2” mutants were all localized nuclearly. These results suggest that deletion of the cNES inhibits nuclear export of the HPV16 L2 minor capsid protein. / Thesis (BS) — Boston College, 2011. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: College Honors Program. / Discipline: Biology Honors Program. / Discipline: Biology.
84

Investigation of Disparities in Cervical Cancer Prevention in the United States: HPV Vaccination and PAP Screening in 18-30 Year Old Women

Newransky, Chrisann January 2013 (has links)
Thesis advisor: James Lubben / In 2011, an estimated 12,710 women suffered from cervical cancer and 4,290 died from it in the U.S. HPV vaccination (HPV-V) and PAP screening (PAP-S) could reduce this burden. Using 2010 National Health Interview Survey data, current disparities in the use of PAP-S and HPV-V in U.S. women aged 18-30 years were investigated. An adapted Behavioral Model of Health Care Utilization guided the study. Main outcomes were PAP-S in prior year and ever-HPV-V, both initiation and completion. Adjusted predictor estimates were obtained through multivariate logistic regressions with appropriate statistical procedures and weights for complex survey design. A sub-analysis focused on unvaccinated women. The sample had 3,129 women aged 18-30 years, representing about 27 million women of similar age in the U.S. PAP-S, HPV-V initiation and completion rates were 53.5%, 17.9%, and 10.3%, respectively. Hispanics were 33% less likely than Non-Hispanic-Whites to initiate HPV-V. Non-Hispanic-Blacks were 55% more likely and 57% less likely than Non-Hispanic-Whites to receive PAP-S and complete HPV-V, respectively. Non-Hispanic Asians were 36% less likely than Non-Hispanic-Whites to receive PAP-S, but this result was borderline significant. Younger age and being unmarried were predictors of lower PAP-S but higher HPV-V. Ever gave birth was a predictor of higher PAP-S but lower HPV-V. Preventative behaviors (PAP-S and flu vaccination) were predictors of higher HPV-V. STI-history was a predictor of higher HPV-V and PAP-S. Not having health insurance for over one year or recent health provider visit were predictors of lower PAP-S and HPV-V. Living in the South was a predictor of lower HPV-V. Household income was not a predictor of any outcomes. Most common reported reason for no HPV-V was "no need." Study findings indicate interventions to mitigate disparities in cervical cancer prevention are needed. Tailored education interventions for both women and health care providers along with opportunities associated with the 2010 Affordable Care Act, such as broader access to health care, emphasis on health information technology, and initiatives with PAP screening and adult vaccination as potential quality indicators for performance/payment, can reduce these disparities. Future research should focus on the feasibility of alternative venues for receiving HPV-V and PAP-S. / Thesis (PhD) — Boston College, 2013. / Submitted to: Boston College. Graduate School of Social Work. / Discipline: Social Work.
85

Correlação colpo-cito-histológica da infecção pelo papilomavírus humano em adolescentes com atividade sexual / Colposcopic, cytologic and histologic findings correlation with human papillomavirus infection in sexually active adolescents

Tubaki, Márcia Emy 04 May 2004 (has links)
Este estudo prospectivo foi delineado com o objetivo de avaliar os achados citológicos, colposcópicos e histológicos da infecção pelo papilomavírus humano em adolescentes e estabelecer a correlação entre o resultado da colpocitologia oncológica e os fatores de risco para a infecção pelo papilomavírus humano. O grupo foi constituído por 82 adolescentes entre 13 e 19 anos, acompanhadas no Ambulatório de Adolescentes e encaminhadas ao Setor de Patologia do Trato Genital Inferior e Colposcopia da Clínica Ginecológica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. As pacientes foram submetidas a anamnese, coleta da colpocitologia oncológica, colposcopia e biópsia de colo uterino na presença de aspectos colposcópicos anormais. A média etária das pacientes foi de 17,7 anos, com desvio-padrão de 1,4 anos. A colpocitologia oncológica foi normal em 57% e alterada em 43%. Os achados citológicos anormais diagnosticados foram: lesão intra-epitelial escamosa de baixo grau em 38%, lesão intra-epitelial escamosa de alto grau em 4% e células escamosas atípicas de significado indeterminado em 1%. A colposcopia foi satisfatória em todos os casos. Os achados colposcópicos normais foram o epitélio pavimentoso original em 4%, epitélio cilíndrico em 18% e a zona de transformação normal em 28%. A zona de transformação anormal estava presente em 50% dos casos, sendo representada pelas alterações epiteliais em 52%, seguida das vasculares em 41% e mistas em 7%. O exame histológico do material de biópsia de colo uterino diagnosticou cervicite crônica em 33%, cervicite crônica associada à infecção pelo papilomavírus humano em 2,4%, neoplasia intra-epitelial cervical grau 1 em 11%, neoplasia intra-epitelial cervical grau 2 em 2,4% e neoplasia intra-epitelial cervical grau 3 em 1,2%. Quanto aos fatores de risco e sua associação com o resultado da colpocitologia oncológica, a análise univariada dos parâmetros idade, menarca, início da atividade sexual, intervalo entre menarca e primeira relação sexual, número de parceiros, tabagismo e método contraceptivo não apresentou diferença estatisticamente significante. A análise conjunta das variáveis independentes através do método de regressão logística identificou os parâmetros idade, menarca e método contraceptivo como fatores relevantes. O aumento em um ano na idade da adolescente diminui a probabilidade (30%) de alteração no resultado citológico. O atraso em um ano na menarca reduz a probabilidade (35%) de colpocitologia oncológica alterada. A utilização de método anticoncepcional hormonal (anticoncepcional oral ou injetável) aumenta a probabilidade de alteração citológica / This prospective study was designed to evaluate the cytologic, colposcopic and histologic findings related to human papillomavirus infections in adolescents and to correlate cytologic reports with risk factors. The study sample consisted of 82 adolescents from 13 to 19 years of age, who were examined in a hospital-based adolescent clinic and referred to Inferior Genital Tract Disease and Colposcopy Unit in the Gynecologic Department - Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Every adolescent answered a questionnaire administered by the physician and afterwards underwent cytologic and colposcopic examination followed by cervical biopsy when colposcopic abnormalities were found. Participant mean age was 17.7 years old and the standard-deviation was 1.4 years. Normal patterns of cytologic findings were present in 57% of the cases. Abnormalities were found in 43%. Abnormal cytologic findings were placed as follows: low-grade squamous intraepithelial lesion in 38%, high-grade squamous intraepithelial lesion in 4% and atypical squamous cells of undetermined significance in 1%. All colposcopic examination were satisfactory. Normal colposcopic appearance was represented by original squamous epithelium in 4%, columnar epithelium in 18% and transformation zone in 28%. Abnormal colposcopic findings corresponded to 50% of the cases, distributed in epithelial abnormalities in 52%, followed by vascular pattern in 41% and both (epithelial and vascular pattern) in 7%. Histological exam of cervical biopsy specimen revelead chronic cervicitis in 33%, chronic cervicites associated with human papillomavirus infection in 2.4%, cervical intra-epithelial neoplasia grade 1 in 11%, cervical intraepithelial neoplasia grade 2 in 2.4% and cervical intraepithelial neoplasia grade 3 in 1.2%. Univariate analysis was used to correlate the concerning risk factors such as age, menarche, sexual activity onset, interval between menarche and first sexual intercourse, number of sexual partners, smoking and contraceptive method, and cytologic results and no statistically significant correlation was found. Logistic regression modelling was used to determine variables associated with abnormal cytology and pointed up age, menarche and hormonal contraceptive method as relevant factors. Aging one year decreases the probability (30%) of abnormal cytology, as well as, delay in one year in menarche results in reduction (35%) of abnormal cervical cytology. Hormonal contraceptive methods (oral contraceptives and injection) increase the probability of cytologic abnormalities
86

CONHECIMENTO DE ENFERMEIRAS ACERCA DA VACINA ANTI-HPV, INFECÇÃO PELO HPV E CÂNCER DO COLO UTERINO / NURSES KNOWLEDGE ABOUT ANTI-HPV VACCINE, HPV INFECTION AND CERVICAL CANCER

Medeiros, Edinilza da Silva Machado 14 March 2016 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2016-11-10T11:31:22Z No. of bitstreams: 1 EDINILZA DA SILVA MACHADO MEDEIROS.pdf: 5001760 bytes, checksum: b5b35c8438c5ad0ee37d875a2d0aef41 (MD5) / Made available in DSpace on 2016-11-10T11:31:22Z (GMT). No. of bitstreams: 1 EDINILZA DA SILVA MACHADO MEDEIROS.pdf: 5001760 bytes, checksum: b5b35c8438c5ad0ee37d875a2d0aef41 (MD5) Previous issue date: 2016-03-14 / This is a cross-sectional cohort study, descriptive with quantitative approach, performed in Public Health Units of cities inside of Bahia, Brazil, with 33 professionals. Data were collected through a multiple-choice questionnaire that intended to investigate the knowledge of the anti-HPV vaccine, HPV infection and cervical cancer, as well as seek association between knowledge with time and institution of training, participation in continuing education and hours worked per week. Data were analyzed using the SPSS® statistical package, version 23. It was adopted a level of significance of 5% (p <0.05). For the verification of possible associations, it was adopted the Pearson's chi-square (χ2) using the verisimilitude ratio coefficients. The results showed nurses with an average age of 30.6 (± 7.3) years; more than 80% from private institution; 51.5% with training time between 2 and 5 years; 84.8% with participation at permanent education; 39.4% with a work load of over 40 hours. All of them knew of the HPV virus and the sexual transmission. However, few knew the other forms of transmission, the effectiveness of condoms, classification and purpose of the Pap test. 90.9% of Nurses understood the role of HPV in the genesis of cervical cancer and genital warts. 97.0% knew the anti-HPV vaccine, but 51.5% thought that only women could be immunized. There was no significant association between time and institution of training, participation in permanent education, as well as hours of weekly work with the knowledge of these professionals on the subject. The study revealed that the nurses have divergent knowledge about the anti-HPV vaccine, HPV infection and cervical cancer, which justifies the needing for improvement of these professionals. / Trata-se de um estudo de corte transversal, de caráter descritivo com abordagem quantitativa, realizado em Unidades Públicas de Saúde de um Município do interior da Bahia, Brasil, com 33 profissionais. Os dados foram coletados por meio de um questionário contendo questões de múltipla escolha que buscaram investigar o conhecimento sobre a vacina anti-HPV, a infecção pelo HPV e o câncer de colo uterino, além de buscar associação entre o conhecimento com o tempo e instituição de formação, participação em educação permanente e carga horária de trabalho semanal. Os dados foram analisados por meio do pacote estatístico SPSS®, versão 23. Adotou-se um nível de significância de 5% (p < 0,05). Em verificação das possíveis associações, adotou-se o teste do Qui-quadrado de Pearson (χ2), utilizando os coeficientes da razão de verossimilhança. Os resultados mostraram Enfermeiras com média de idade de 30,6 (± 7,3) anos; mais de 80% proveniente de instituição particular; 51,5% com tempo de formação entre 2 e 5 anos; 84,8% com participação em educação permanente; 39,4% com carga horária de trabalho de mais de 40 horas. Todas sabiam da existência do vírus HPV e a transmissão pela via sexual. Todavia, poucas conheciam as demais formas de transmissão, a eficácia do preservativo, a classificação e objetivo do exame de Papanicolau. Entendiam o papel do HPV na gênese do câncer cervical e das verrugas genitais 90,9% das Enfermeiras. 97,0% conheciam a vacina anti-HPV, mas 51,5% achavam que apenas as mulheres poderiam ser imunizadas. Não houve associação significativa entre tempo e instituição de formação, participação em educação permanente, bem como carga horária de trabalho semanal com o conhecimento destas profissionais sobre a temática. Ficou evidenciado que as Enfermeiras possuem conhecimentos divergentes sobre a vacina anti-HPV, infecção pelo HPV e câncer de colo uterino, o que justifica a necessidade de aprimoramento por partes destas profissionais.
87

Idade e prevalência da infecção genital por papilomavírus humano de alto risco em mulheres submetidas a rastreamento para câncer cervical / Age and prevalence of high risk human papilomavirus genital infection in women submitted to cervical cancer screening

Rama, Cristina Helena 06 July 2006 (has links)
Introdução: A relação causal entre infecção genital por papilomavirus humano (HPV) de alto risco e o câncer do colo uterino está bem estabelecida; porém, há controvérsias em diferentes populações quanto à prevalência e distribuição da infecção em relação à idade. Objetivos: Caracterizar, pela Captura Híbrida II (CHII), a prevalência da infecção genital por HPV de alto risco e sua estratificação por idade. Verificar a associação da infecção com fatores de risco, resultados da citologia oncológica (CO), da colposcopia e da biópsia cervical. Casuística e Métodos: Em estudo transversal estudou-se 2300 mulheres (15-65 anos) que buscaram rastreamento para o câncer cervical. Aplicou-se questionário epidemiológico e foi feita a coleta da CO e da CHII, no caso de alteração em destes exames ou ambos indicou-se colposcopia e, nos casos anormais, procedeu-se à biópsia cervical. Resultados: A prevalência da infecção genital por HPV de alto risco em toda amostra foi de 17,8%: 27% (<25 anos), 21% (25-34 anos), 12% (35-54 anos) e de 14% (55-65 anos). Participantes com maior número de parceiros sexuais durante a vida apresentaram uma maior chance de infecção, relacionamento estável, idade entre 30 a 54 anos e ser ex-fumante foram fatores associados à proteção da infecção. Encontrou-se 204 (8,8%) CO anormais e uma relação direta entre severidade do diagnostico citológico e infecção por HPV de alto risco, 14,3% em citologia normal, 78% em lesão escamosa de alto grau, 100% nos esfregaços compatíveis com carcinoma. Foram histologicamente confirmados: 10 casos de Neoplasia intra-cervical grau 2/3 (NIC2/3) entre as mulheres infectadas por HPV, com citologia normal; 4 NIC 2/3 e um carcinoma nas que apresentavam exclusivamente alteração citológica e 15 NIC 2/3 e 3 carcinomas em mulheres com ambos os testes positivos. Conclusão: A prevalência da infecção genital por HPV de alto risco foi alta, seguindo uma curva na qual se observou novo aumento da prevalência após os 55 anos. / The causal role of high risk human papillomavirus (HPV) infection and cervical cancer has been well documented. However HPV prevalence varies greatly across populations, as might the age distribution. Objective: We aimed to determine high risk HPV prevalence and its distribution by age groups. Risk factors, cytological, colposcopic and cervical biopsies results associated with high risk HPV infection in a sample of women who self referred for cervical cancer screening. Methods: In a cross sectional study we interviewed and obtained cervical specimens from a sample of randomized 2300 women (15-65 years). Specimens were tested for the presence of high risk HPV using Hybrid Capture II (HCII) and for cervical cytological abnormalities by Pap smears or liquid based cytology. Women, who had abnormal cytology or positive HCII, or both results, were referred to colposcopy examination. Whenever colposcopy revealed an abnormal pattern, a directed punch biopsy was taken. Results: Four hundred and eight (17.7%) study participants tested positive for high risk HPV types by HC2: 27% (<25 years), 21% (25-34 years), 12% (35-54 years) and 14% (55-65 years). The main risk factor for HPV infection was number of lifetime sexual partners; age at 30 to 54 years, women who live with a partner and former smokers were negative associated with high risk HPV infection. Two hundred four (8, 8%) women had cytological abnormalities. HC II positive was associated with cytology outcome (14, 3% in normal cytology, 78% in HSIL and 100% in cervical cancer). Cervical Intraepithelial Neoplasia grade 2/3 (CIN 2/3) were found in 10 HPV infected women with normal cytological results. Women with abnormal cytological results only had 4 CIN 2/3 and 1 carcinoma and women testing positive in both techniques had 15 CIN 2/3 and 3 carcinomas. Conclusions: High risk HPV prevalence was high in this sample and the prevalence age curve showed a second pick starting around 55 years old.
88

Estudo de células dendríticas, expressão das citocinas TNF-alfa, IFN-gama e IL-10 e da molécula de adesão E-caderina em lesões vulvares induzidas pelo papilomavírus humano / Study of dendritic cells, cytokines TNF-alpha, IFN-gamma and IL-10 and the adhesion molecule E-cadherin in vulvar lesions induced by human papillomavirus

Pereira, Naiura Vieira 14 April 2009 (has links)
INTRODUÇÃO: O papilomavírus humano (HPV) é o agente mais frequentemente encontrado em doenças sexualmente transmissíveis e é responsável por cerca de 40% dos cânceres vulvo-vaginais. Esse trabalho abordou a resposta imune em lesões vulvares, considerando-se as células dendríticas CD1a+, FXIIIa+ e S-100+, citocinas TNF-, IFN- e IL-10 e a molécula de adesão E-caderina. MÉTODOS: Foram utilizadas 49 lesões de vulva pelo HPV (condiloma acuminado, NIV-I, NIV-II e NIV-III) e 11 bióspias com diagnóstico de vulvite crônica inespecífica. Foram constituídos quatro grupos: lesões de baixo grau (condiloma e NIV I), lesões de alto grau (NIV II e III), vulvites inespecíficas e pele normal. A detecção das células, citocinas e E-caderina foi feita através de método imuno-histoquímico. RESULTADOS: As células de Langerhans (CD1a+) estavam distribuídas em todo o epitélio, sobretudo nas camadas suprabasal e espinhosa. Não diferiram entre os grupos de lesões HPV+, mas estavam diminuídas em número e tamanho quando comparadas à pele normal (p<0.0001). As células S-100+ ou FXIIIa+ estavam localizadas em toda a extensão do estroma, sem diferença estatística entre as lesões pelo HPV. Embora os DDFXIIIa+ estivessem aumentados em tamanho nas lesões de vulva, seu número não diferiu da pele normal. Não se observou diferenças numéricas das células S-100+ entre os grupos de lesão e pele normal. Foi possível detectar maior número de DDFXIIIa+ sobre as células S-100+ no grupo de lesões de baixo grau (p = 0,0008) e de alto grau (p = 0,0031). As citocinas foram detectadas em pequenas quantidades nos grupos de lesões, porém sem diferença estatística. Para a análise da expressão de e-caderina, o grupo de vulvites crônicas inespecíficas foi utilizado como controle. Em 91.0% das vulvites inespecíficas foi observado padrão homogêneo e difuso da expressão de e-caderina na camada espinhosa baixa e média. Ambos os grupos de lesões HPV+ exibiram padrões semelhantes de expressão de e-caderina, com marcação difusa ou focal na camada espinhosa baixa e média. Não houve imuno-reatividade nas áreas de displasias. Como resultado da reação de dupla-marcação, feita através da utilização da hibridização in situ para detecção do DNA do HPV e imunohistoquímica para DDFXIIIa+, foi possível identificar antígenos virais no citoplasma dessas células. CONCLUSÕES: o HPV interfere na expressão das células de Langerhans, pois estas estavam diminuídas, com morfologia alterada em relação à pele normal; os DDFXIIIa+ apresentam-se aumentados em número sobre as células S-100+, o que poderia refletir um mecanismo local compensatório contra o HPV; as lesões de baixo e alto grau não apresentam diferenças significativas quanto à densidade de células expressando TNF-, IFN- e IL-10, embora TNF- predomine entre as três citocinas; há uma correlação positiva entre os DDFXIIIa+ e a expressão de TNF-, o que poderia ser explicado por sua capacidade em produzir tal citocina a partir de um provável estímulo desencadeado pelo HPV; o HPV influencia na expressão de E-caderina na vulva, com destaque para a ausência de expressão nas áreas de displasia; o DNA do HPV encontrado no interior dos DDFXIIIa+ aliado às alterações na morfologia celular, a sobreposição destas sobre as células S-100+ e a relação encontrada com a citocina TNF-, nos permitem sugerir que os DDFXIIIa+ têm um papel importante como células apresentadoras de antígeno frente à infecção pelo HPV. / INTRODUCTION: The human papillomavirus (HPV) is the most frequent agent in sexually transmitted diseases and is responsible for almost 40% of vulvovaginal cancer. We studied the immune response in vulvar lesions, considering the CD1a+, FXIIIa+ and S-100+ dendritic cells, TNF-, IFN- and IL-10 cytokines and the adhesion molecule E-cadherin. METHODS: We used 49 vulvar lesions mediated by HPV (condylomata acuminata, VIN-I, VIN-II e VIN-III) and 11 biopsies diagnosed as chronic non-specific vulvitis. Four groups were formed: low-grade lesions (condylomata and VIN-I), high-grade lesions (VIN-II and III), non-specific vulvitis and normal skin. The detection of cells, cytokines and e-cadherin was performed by immunohistochemistry reaction. RESULTS: Langerhans cells (CD1a+) were distributed through epithelia, mainly in suprabasal and spinous layer. They did not differ between HPV groups, but were decreased in number and size when compared to normal skin (p<0.0001). The S-100+ ou FXIIIa+ cells were distributed through stroma and did not differ between HPV lesions. Although the FXIIIa+DD were increased in size in vulvar lesions, their number did not differ from normal skin. The S-100+ cells did not differ in number between the groups of lesions and normal skin. We detected an increased number of FXIIIa+DD over S-100+ cells in the group of low-grade (p = 0.0008) and high-grade lesions (p = 0.0031). The cytokines were detected in small quantities in both the lesions groups, with no statistical difference. The group of chronic non-specific vulvitis was used as control group to analyse the expression of e-cadherin. 91.0% of non-specific vulvitis presented a homogeneous and diffuse pattern of expression in spinous layer Both the HPV+ groups of lesions presented similar patterns of e-cadherin expression, with a focal or diffuse localization in spinous layer. The dysplastic epithelium did not present immunoreactivity. As a result of the double-staining, using in situ hibridization to detect DNA of HPV and immunohistochemistry to FXIIIa+DD, it was possible to observe viral antigens in the cytoplasm of such cells. CONCLUSIONS: The HPV interfere with the expression of Langerhans cells, since they were decreased when compared to the normal skin; the FXIIIa+DD were increased in number over S-100+ cells, suggesting a local compensatory mechanism against the HPV; the low and high grade lesions did not differ in the number of cells expressing TNF-, IFN- and IL-10, although TNF- predominate among the three cytokines; there is a positive correlation between the FXIIIa+DD and the expression of TNF- that could be explained by their role as TNF-producing cells following a stimulus of HPV; the HPV changes the expression of E-cadherin in vulvar lesions, mainly in dysplastic epithelium; HPV DNA visualized in the cytoplasm of FXIIIa+DD and the cellular morphological changes, the increased number over S-100+ cells and the correlation with TNF-, allow us to suggest that FXIIIa+DD play an important role as antigen presenting cells in the infection by HPV.
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Análise dos fatores de risco no carcinoma espinocelular de cabeça e pescoço: tabagismo e HPV / Analysis of risk factors in squamous cell carcinoma of head and neck: smoking and HPV

Affonso, Vivian Regina 25 November 2016 (has links)
Introdução: O câncer de cabeça e pescoço vem aumentando sua incidência, sendo o quinto tipo de câncer mais comum e a sexta causa de morte por câncer no mundo, portanto é causa importante de morbimortalidade da população. O entendimento dos fatores de risco como tabagismo, etilismo e infecção pelo papilomavirus (HPV) é de fundamental importância, tanto para ações de prevenção e controle da doença, bem como avaliação de fatores prognósticos e terapêuticos. Objetivos: O presente estudo visa analisar as características clínicas, buscar o principal sítio anatômico tumoral e avaliar os fatores prognósticos entre os pacientes tabagistas ou não, e portadores ou não do HPV, que foram tratados cirurgicamente. Casuística e Métodos: Foram analisadas as variáveis clínicas e prognósticas dos grupos de pacientes tabagistas, não tabagistas, HPV negativo e HPV positivo. A amplificação do DNA viral, detecção e genotipagem do HPV se deu através da extração do DNA total a partir de blocos parafinados. Resultados: A amostra total foi composta por 399 pacientes, sendo que 266 eram tabagistas, 33 não tabagistas, e desses últimos, cinco eram HPV positivo. Houve diferença estatística em relação sexo, sendo que para o tabagista o predomínio foi do sexo masculino e para o HPV positivo foi o feminino. O paciente tabagista apresentou-se mais jovem (média 57,9 anos) que o não tabagista (média 64,1 anos). O sítio anatômico mais comum para os tabagistas foi a laringe e para o HPV positivo foi a cavidade oral e orofaringe. O tempo livre de doença foi de 63,6 meses para os tabagistas, 31,3 meses para os não tabagistas e 29,3 meses para os HPV positivo, havendo diferença quanto às curvas de sobrevidas livre da doença dos fumantes e não fumantes. Dos pacientes que foram á óbito pela neoplasia, o paciente HPV positivo foi o que apresentou menor tempo de sobrevida. Não houve diferença estatística entre os grupos quanto às curvas de sobrevidas global e da doença. Discussão: Apesar da literatura mostrar que o paciente não tabagista e o paciente HPV positivo geralmente serem mais jovens e apresentarem melhor prognóstico do que os típicos pacientes tabagistas, isso não foi observado nesse estudo, pois o paciente não tabagista apresentou-se com mais idade ao diagnóstico da doença e com pior prognóstico que o tabagista, e o paciente HPV positivo apresentouse com menor tempo até o óbito pela doença quando comparado ao paciente tabagista. Conclusões: O câncer nos pacientes tabagistas acometeu mais o sexo masculino, localizou-se principalmente na laringe e apresentou melhor prognóstico quando comparado aos não tabagistas. O câncer nos pacientes HPV positivo acometeu mais o sexo feminino e localização tumoral foi principalmente a cavidade oral e a orofaringe. / Introduction: Head and Neck cancer has been increasing its incidence, and it is the fifth most common type of cancer and the sixth leading cause of cancer death in the world, so it is an important cause of morbidity and mortality of the population. Understanding the risk factors such as smoking, alcohol use and papillomaviruses (HPV) infection is of fundamental importance, both for prevention and control of disease like for assessment of prognostic and therapeutic factors. Objectives: This study aims to analyze the clinical, seek the main site anatomical of the tumor and evaluate the prognostic factors among smokers or not, with the presence or absence of the HPV, which were surgically treated. Methods: The variables clinical and prognostic were analyzed in the groups of smokers, nonsmokers, HPV negative and HPV positive. The amplification of viral DNA, detection and genotyping of the HPV were made through the extraction of total DNA from paraffin blocks. Results: The total sample consisted of 399 patients, 266 were smokers, 33 nonsmokers, and this latter group had five patients HPV positive. There was statistical difference regarding sex, for smokers the prevalence was male and for HPV positive was female. The smoker patient was younger (mean 57.9 years) than the non-smoker (mean 64.1 years). The most common anatomic site for the smokers was the larynx and for the HPV positive was the oral cavity and oropharynx. The diseasefree interval was 63.6 months for smokers, 31.3 months for nonsmokers and 29.3 months for HPV positive, with difference between free disease survival curves of the smokers and nonsmokers. Of the patients who died by disease, HPV positive patient showed the shorter survival. There was no statistical difference between the groups in terms of overall survival curves and of the disease. Discussion: Although the literature show that the nonsmoker patient and HPV positive patients are generally younger and present a better prognosis than the typical smokers, this was not observed in this study because the nonsmoker patient presented with more age at diagnosis of disease and a worse prognosis than the smoker, and the HPV positive patient presented with shorter survival of the disease when compared to smoking patients. Conclusions: The cancer in smokers affected more males, was located mainly in the larynx and showed better prognosis when compared to nonsmokers. The cancer in patients positive HPV affected more females and tumor location was mainly oral cavity and oropharynx.
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L’axe de signalisation CXCL12/CXCR4 : un nouveau facteur de l’hôte impliqué dans la carcinogenèse induite par les papillomavirus humains / The CXCL12/CXCR4 signaling pathway : a new host factor involved in human papillomavirus-induced carcinogenesis

Meuris, Floriane 11 September 2015 (has links)
Les papillomavirus humains (HPV), dont on dénombre plus de 300 types différents, infectent spécifiquement les épithéliums. Ces infections sont communes et généralement asymptomatiques. Cependant, lorsqu’elles persistent, elles peuvent donner lieu à des lésions bénignes, telles que les verrues, ou cancéreuses, telles que le cancer du col de l’utérus. Les facteurs de l’hôte impliqués dans la persistance et la pathogénie des infections par les HPV restent largement méconnus. Les premières évidences du rôle de l’axe de signalisation CXCL12/CXCR4 dans la pathogénie virale proviennent d’observations faites dans le contexte d’un déficit immunitaire rare, le syndrome WHIM. En effet, ce syndrome est dû à des dysfonctions de l’axe CXCL12/CXCR4 − causées par des mutations de CXCR4 conduisant à un gain de fonction de l’axe CXCL12/CXCR4 − et est caractérisé par une susceptibilité sélective des patients à des infections sévères, persistantes et parfois malignes par les HPV. Au vu de cette susceptibilité, l’objectif de ma thèse a été d’approfondir cet éventuel lien causal entre les dysfonctions de l’axe CXCL12/CXCR4 et la pathogenèse associée aux infections par les HPV et de caractériser les mécanismes moléculaires en jeu.Afin de répondre à cette problématique, je me suis intéressée dans la première partie de mes travaux de thèse aux conséquences des dysfonctions de l’axe CXCL12/CXCR4 − à travers le gain de fonction de CXCR4 associé au syndrome WHIM − sur le cycle biologique d’HPV18 étudié dans des cultures organotypiques épithéliales tridimensionnelles. Ces travaux nous ont permis de mettre en évidence que les dysfonctions de CXCR4 limitaient la production virale au profit de la mise en place d’un processus de transformation cellulaire. Les mécanismes en jeu impliquent une augmentation de la prolifération cellulaire et un changement du profil d’expression des protéines virales en faveur des oncoprotéines et au détriment de celles impliquées dans la réplication virale.Dans la seconde partie de mes travaux, je me suis attachée à déterminer les effets du blocage de l’axe CXCL12/CXCR4 dans un modèle murin de néoplasie épithéliale induite par HPV16 (souris K14-HPV16). Le traitement de ces souris par l’AMD3100, un antagoniste sélectif de CXCR4, induit une tendance à la normalisation se manifestant par une diminution significative de l’hyperplasie induite par HPV16. Cet effet est associé à une réduction de l’hyperprolifération des kératinocytes et de l’infiltrat de cellules immunitaires dans le derme.En conclusion, ce travail de thèse identifie l’axe CXCL12/CXCR4 comme un facteur de l’hôte impliqué dans la carcinogenèse induite par les HPV, et révèle le bénéfice de stratégies thérapeutiques basées sur le blocage de cet axe. / Human papillomaviruses (HPVs), which encompass almost 300 different types identified so far, specifically infect epitheliums. Most of the time, HPVs are associated with asymptomatic infections suggesting an efficient control by the host immune system. However, when these infections persist, HPVs can cause cutaneous warts but also mucosal lesions that can progress to dysplasia and cancer (e.g. cervical cancers). The host factors involved in HPV persistence and derived-pathogenesis remain quite obscure. The first evidence for a role of the CXCL12/CXCR4 signaling axis in HPV pathogenesis came from observations made in the context of a rare immunodeficiency disorder, the WHIM syndrome. This syndrome is caused by dysfunctions of the axis formed by the chemokine CXCL12 and its receptor CXCR4 – caused by inherited heterozygous mutations in CXCR4 leading to a gain-of-function of the CXCL12/CXCR4 axis – and featured by a high susceptibility to severe, persistent and sometimes malignant HPV infections. In light of this susceptibility, the aim of my thesis was to characterise the molecular mechanisms involved and to find out whether it extend to a more general interplay between the CXCL12/CXCR4 axis and HPV biological cycle and pathogenesis.In the first part of my work, I investigated the consequences of CXCL12/CXCR4 dysfunctions – through the CXCR4 gain-of-function – on the HPV18 life cycle in three-dimensional organotypic epithelial cultures. We found that CXCR4 dysfunctions limited the viral replication at the benefit of cell transformation. The mechanisms included an increased in cell proliferation and a change in viral protein expression profile in favour of oncoproteins and at the expense of proteins involved in viral replication.In the second part of my work, I determined the impact of the CXCL12/CXCR4 blockade on a murin model of HPV16-induced neoplasia (K14-HPV16 mice). Treatment of these mice by AMD3100, a selective antagonist of CXCR4, results in a normalisation of HPV-induced lesions manifested by a significant decrease of skin hyperplasia. This effect is associated with a reduction in keratinocyte hyperproliferation and immune cell infiltration in dermis.To conclude, this thesis work identifies the CXCL12/CXCR4 axis as a new host factor involved in human papillomavirus-induced carcinogenesis, and reveals the benefit of therapeutic strategies based on the blockade of this axis.

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