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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.
41

Avaliação da excreção genital do HIV-1 em mulheres menopausadas e em idade fértil: prevalência e fatores associados / HIV cervicovaginal shedding among postmenopausal and fertile-aged women: prevalence and associated factors

Keli Cardoso de Melo 14 December 2009 (has links)
INTRODUÇÃO: Poucos estudos têm focado as modificações fisiológicas que ocorrem no trato genital de mulheres menopausadas infectadas pelo HIV e sua associação com a excreção genital do vírus. Nesse estudo de corte transversal, comparou-se a excreção genital do HIV em mulheres menopausadas e em idade fértil em acompanhamento em um centro especializado em São Paulo, Brasil. Investigou-se também a associação entre a excreção genital de RNA de HIV e a viremia em ambos os grupos. Fatores associados com a intensidade da excreção genital de HIV também foram pesquisados, incluindo achados ginecológicos e marcadores de progressão da infecção por HIV. MÉTODOS: 146 mulheres infectadas pelo HIV [73 menopausadas (M)/73 em idade fértil (F)] foram selecionadas em Serviço de Extensão ao Atendimento de Pacientes com HIV/Aids Casa da Aids do Hospital das Clínicas da FMUSP, São Paulo, Brasil. As mulheres menopausadas referiram tempo médio de 8,17 anos (DP=6 anos) de menopausa. A contagem de linfócitos T CD4+ foi obtida por citometria de fluxo e a quantificação do RNA do HIV no plasma e no lavado cervicovaginal (LCV) foi realizada por RT-PCR quantitativo, utilizando-se o kit Cobas Amplicor HIV-1 Monitor Test®, no método ultrasensível. Cloreto de lítio foi introduzido no tampão para obtenção do LCV e quantificado antes e depois da coleta do lavado, a fim de determinar o fator de diluição de cada amostra. A deteção do gene SRY por PCR também foi realizada a fim de eliminar amostras com eventual contaminação espermática. A prevalência de excreção genital foi estimada para ambos os grupos e os fatores associados à intensidade da excreção viral foram investigados, utilizando-se modelo de regressão linear múltipla. As variáveis com p<0,2 na análise bivariada foram incluídas na análise multivariada, assim como o grupo em estudo (M ou F). O modelo final incluiu fatores que se mostraram independentemente associados com a intensidade da excreção genital de HIV. RESULTADOS: A prevalência de excreção genital de HIV-RNA foi similar em ambos os grupos (M: 17,8%, IC 95% 9,8 28,5; F: 22%, IC 95% 13,1 33,1, p=0,678). Similarmente, a intensidade de excreção genital do HIV também não se mostrou diferente entre os grupos (mediana - M: 1,4log/mL; F: 1,4log/mL, p=0,587). A carga viral plasmática foi detectável em 34,2% das pacientes menopausadas (IC 95% 23,5 46,3) e em 42,5% entre as pacientes em idade fértil (IC 95% 31 54,6, p=0,395). Três pacientes (2 M/1 F) exibiram excreção genital de HIV-RNA na ausência de viremia detectável. Existe evidência de correlação entre a carga viral plasmática e a genital em ambos os grupos (rM: 0,658; rF: 0,684, p<0,01). Adicionalmente, o número de células CD4+ periféricas mostrou-se negativamente correlacionada à excreção genital do HIV em ambos os grupos (rM: -0,250; rF: -0,248, p<0,05). À análise multivariada, a carga viral plasmática mostrou-se independentemente associada à ocorrência de excreção genital do HIV em ambos os grupos (OR 4,03, IC 95% 2,52 6,45, p<0,001). Já a intensidade de excreção genital mostrou-se independentemente associada ao pH vaginal (p<0,001), concentração de TNF- no LCV (p=0,01), e à carga viral plasmática (p=0,001), todos com correlação positiva. CONCLUSÕES: Apesar das modificações significativas que ocorrem na mucosa vaginal da mulher menopausada, a excreção cervicovaginal do HIV parece não ser significativamente influenciada por esse estado. A carga viral plasmática e o número de células CD4+ periféricas estão correlacionadas com a excreção genital do vírus. A frequência de excreção genital mostrouse independentemente associada à intensidade de viremia. Além disso, o aumento do pH vaginal e evidência de inflamação genital, associada à concentração de TNF- no LCV, independentemente aumentam a intensidade de excreção genital nas mulheres estudadas. / BACKGROUND: Few studies have focused on physiological modifications that occur in the genital tract of HIV-infected postmenopausal women and their association with HIV cervicovaginal shedding. In this cross-sectional study we evaluated and compared HIV genital shedding among postmenopausal and fertile-aged women under care at a specialized center in Sao Paulo, Brazil, investigating the association between HIV-RNA shedding and HIV plasma viral loads in both groups. Factors associated with higher HIV shedding were also investigated, including gynaecological features and HIV disease progression markers. METHODS: 146 women living with HIV [73 postmenopausal (PM)/73 in fertile-aged (F)] were enrolled at the HIV Clinic, University of São Paulo Medical School, Brazil. Postmenopausal women referred a mean duration of 8.17y (SD=6y) since menopause. CD4+ cell counts were obtained by flow cytometry and HIV-RNA was quantified in plasma and in cervicovaginal lavages (CVL) by RT-PCR, using Cobas Amplicor HIV-1 Monitor Ultrasensitive Test. Lithium chloride was introduced into the CVL buffer and measured before and after CVL collection in order to determine the dilution factor for each specimen. SRY gene detection by PCR was also performed in all samples in order to rule out sperm contamination. Prevalence of HIV genital shedding was estimated for both groups and factors associated with the intensity of viral shedding were investigated, using a multiple linear regression model. Variables with p<0.2 in bivariate analysis were included in multivariate analysis, as well as the study group (PM and F). The final model included factors shown to be independently associated with intensity of HIV genital shedding. RESULTS: The prevalence of HIV-RNA genital shedding was similar in both groups. (PM: 17.8%, 95%CI 9.8 28.5; F: 22%, 95%CI 13.1 33.1, p=0.678). Likewise, the intensity of HIV shedding was shown not to differ between PM and F women (means - PM: 1.4log/mL; F: 1.4log/mL, p=0.587). Plasma viral loads were detectable in 34.2% of PM patients (95%CI 23.5 46.3), as compared to 42.5% among F women (95%CI 31 54.6) (p=0.395). Three patients (2 PM/1 F) exhibited HIV-RNA genital shedding in the absence of detectable viremia. We found evidence of correlation between HIV plasma viral load and HIV cervicovaginal shedding in both groups (rPM: 0.658; rF: 0.684, p<0.01). In addition, CD4+ cell counts were shown negatively correlated to HIV shedding in both groups (rPM: -0.250; rF: -0.248, p<0.05). In multivariate analysis, HIV plasma viral load was shown independently associated with occurrence of HIV genital shedding in both groups (OR 4.03, 95%CI 2.52 6.45, p<0.001). In addition, the intensity of HIV shedding was shown independently associated with vaginal pH (p<0.001), TNF- concentrations in CVL (p=0.01), and with HIV plasma viral loads (p=0.001), all of them with positive correlation. CONCLUSION: Despite the significant changes that occur in the vaginal mucosa of postmenopausal women, HIV cervicovaginal shedding does not seem to be significantly influenced by this state. Plasma viral loads and CD4+ cell counts are correlated to HIV genital shedding. The frequency of HIV genital shedding was shown independently associated with viremia intensity. Moreover, increased vaginal pH and evidence of genital inflammation associated with TNF- concentration independently enhanced the intensity of HIV shedding in postmenopausal and fertile-aged women.
42

Expressão de indoleamina 2,3-dioxigenase (IDO) e triptofano 2,3-dioxigenase(TDO) no ambiente cervicovaginal normal, na vaginose bacteriana e nas lesões cervicais associadas ao HPV / Expression of indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) in normal cervicovaginal environment, bacterial vaginosis and cervical lesions associated with HPV

Paloma Almeida Venancio 04 October 2018 (has links)
Neste estudo avaliamos o papel do metabolismo do triptofano (Trp) na homeostasia, na vaginose bacteriana e nas lesões cervicais associadas ao HPV. A importância do metabolismo do Trp se deve a sua ação na proliferação de microrganismos e de células do sistema imune. O consumo de triptofano tem sido identificado como uma forma de controlar o crescimento bacteriano limitando a infecção. Por outro lado, a oxidação de Trp produz quinurenina (QUIN), que tem papel chave na tolerância imunológica. A formação de QUIN se dá através das enzimas indoleamina 2,3-dioxigenase (IDO) e triptofano 2,3- dioxigenase (TDO). A mais estudada delas no âmbito das infecções/ imuno escape é a enzima IDO. Mais recentemente, tem-se dado ênfase ao papel da TDO no câncer. Nesta dissertação, o interesse foi avaliar a expressão da IDO no epitélio cervicovaginal de mulheres com vaginose bacteriana e de IDO e TDO em amostras cervicais de mulheres com diferentes graus de lesão cervical associada ao HPV. Foram incluídas 165 mulheres atendidas no CAISM/UNICAMP, as quais foram divididas em dois grupos: grupo caso composto por mulheres com lesão de baixo ou alto grau e carcinoma invasor (n=42) e grupo controle composto por mulheres com citologia oncológica normal, independente de apresentar infecção genital (n=123). IDO foi avaliada por imunocitoquímica em citologia em base líquida e IDO e TDO em biópsias cervicais. Mulheres com vaginose bacteriana apresentaram expressão aumentada de IDO em células escamosas em comparação às mulheres sem vaginose bacteriana (OR=7.41; IC 95%= 2.50 a 21.4; p <0.0001). No epitélio vaginal normal com ou sem infecção por HPV houve uma expressão leve de IDO em células escamosas. Na presença de lesões ou carcinoma, houve um aumento no número de células escamosas displásicas e de leucócitos IDO-positivos; aumento de IDO também pôde ser observada em culturas de pele organotípicas transduzidas com as oncoproteínas E6/ E7 do HPV16. Nas lesões cervicais, assim como visto para a IDO, a TDO esteve expressa em leucócitos, especialmente os infiltrados na região estromal e na parede dos vasos sanguíneos. A expressão basal de IDO no epitélio cervical normal e sua regulação positiva na infecção por HPV e lesões associadas sugerem a participação do metabolismo do Trp nos mecanismos imunossupressores envolvidos na doença. Embora o papel do IDO já tenha sido abordada anteriormente, até onde sabemos esta é a primeira evidência da expressão de TDO no epitélio vaginal, na neoplasia intraepitelial cervical e carcinoma de células escamosas. Ainda, em leucócitos, especialmente aqueles com morfologia típica de polimorfonucleares, parecem ser importantes fontes de IDO na cérvix uterina. / In this study we evaluated the role of tryptophan (Trp) metabolism in cervix homeostasis, bacterial vaginosis and HPV-associated lesions. The importance of Trp metabolism is due to its action on microorganisms and immune cells. Tryptophan consumption has been identified as a way to controlling bacterial growth limiting infection. On the other hand, the oxidation of Trp produces kynurenine (Kyn) which plays a key role in immunological tolerance. The formation of Kyn occurs through the enzymes indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO). IDO is the most studied of them within the context of infections / immune escape. More recently, TDO has also been considered in studies of cancer progression. In this thesis, we were interested in cervicovaginal epithelium IDO expression in women with bacterial vaginosis and of IDO and TDO in cervical samples of women with different degrees of cervical lesion associated with HPV. A total of 165 women attended at CAISM/UNICAMP were divided into two groups: a case group composed of women with low or high grade lesions and invasive carcinoma (n = 42) and a control group composed of women with normal cytology, independent to present genital infection (n =123). IDO was evaluated by immunocytochemistry in liquid-based cytology and IDO and TDO in cervical biopsies. Women with bacterial vaginosis had increased IDO expression in squamous cells compared to women without bacterial vaginosis (OR = 7.41, 95% CI = 2.50- 21.74; p<0.0001). In normal vaginal epithelium with or without HPV infection there was a mild IDO expression in squamous cells. In the presence of cervical intraepithelial lesions or squamous cell carcinoma, there was an increase in the number of IDO-positive dysplastic squamous cells and leukocytes; increase in IDO can also be observed in organotypic skin cultures transduced with HPV-16 E6/E7 oncoproteins. In cervical lesions, as observed for IDO, TDO was expressed in leukocytes, especially infiltrates in the stromal region and in the wall of blood vessels. The basal expression of IDO in the normal cervical epithelium and its positive regulation in HPV infection and associated lesions suggests the participation of Trp metabolism in the immunosuppressive mechanisms involved in the disease. Although some previous data have already considered the role of IDO, as far as we know this is the first evidence of the participation of TDO in the vaginal epithelium, cervical intraepithelial neoplasia and squamous cell carcinoma. In addition, in leukocytes, especially those with a typical polymorphonuclear morphology, appear to be important sources of IDO in the uterine cervix.
43

Three-Dimensional Digital Capture of Head Size in Neonates – A Method Evaluation

Ifflaender, Sascha, Rüdiger, Mario, Koch, Arite, Burkhardt, Wolfram 22 January 2014 (has links)
Introduction: The quality of neonatal care is mainly determined by long-term neurodevelopmental outcome. The neurodevelopment of preterm infants is related to postnatal head growth and depends on medical interventions such as nutritional support. Head circumference (HC) is currently used as a two-dimensional measure of head growth. Since head deformities are frequently found in preterm infants, HC may not always adequately reflect head growth. Laser aided head shape digitizers offer semiautomatic acquisition of HC and cranial volume (CrV) and could thus be useful in describing head size more precisely. Aims: 1) To evaluate reproducibility of a 3D digital capture system in newborns. 2) To compare manual and digital HC measurements in a neonatal cohort. 3) To determine correlation of HC and CrV and predictive value of HC. Methods: Within a twelve-month period data of head scans with a laser shape digitizer were analysed. Repeated measures were used for method evaluation. Manually and digitally acquired HC was compared. Regression analysis of HC and CrV was performed. Results: Interobserver reliability was excellent for HC (bias-0.005%, 95% Limits of Agreement (LoA) −0.39–0.39%) and CrV (bias1.5%, 95%LoA-0.8–3.6%). Method comparison data was acquired from 282 infants. It revealed interchangeability of the methods (bias-0.45%; 95%LoA-4.55–3.65%) and no significant systematic or proportional differences. HC and CrV correlated (r2 = 0.859, p<0.001), performance of HC predicting CrV was poor (RSD ±24 ml). Correlation was worse in infants with lower postmenstrual age (r2 = 0.745) compared to older infants (r2 = 0.843). Discussion: The current practice of measuring HC for describing head growth in preterm infants could be misleading since it does not represent a 3D approach. CrV can vary substantially in infants of equal HC. The 3D laser scanner represents a new and promising method to provide reproducible data of CrV and HC. Since it does not provide data on cerebral structures, additional imaging is required.

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