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Prevalência, gravidade e fatores de risco associados à sibilância recorrente em lactentes nascidos em Ribeirão Preto em 2010 / Prevalence, severity and risk factors associated with recurrent wheezing in infants was born in Ribeirão Preto in 2010Juliana Cristina Castanheira Guarato 22 November 2016 (has links)
Objetivo: Avaliar a prevalência, a gravidade e os fatores de risco associados à sibilância recorrente em crianças nos primeiros dois anos de vida em uma coorte de nascimentos. Métodos: Estudo de coorte prospectivo de 3167 crianças nascidas em Ribeirão Preto, SP, no ano de 2010 e avaliadas para esse estudo entre 12 e 24 meses. Os responsáveis pelos lactentes participantes responderam a questionários padronizados com questões referentes às características maternas, condições gestacionais, perinatais e pós-natais, antecedentes pessoais e familiares de doenças alérgicas, ocorrência e número de episódios de sibilância, ida a serviços de emergência, uso de medicações, diagnóstico de pneumonia e internações. O estudo das associações entre os desfechos e as variáveis independentes de interesse foi feito por meio de análise univariada e por modelos log-binomiais ajustados, obtendose medidas de risco relativo (RR) e seus intervalos de confiança (IC). Resultados: A prevalência de pelo menos um episódio de sibilância nos dois primeiros anos de vida foi de 56,3% (1785/3167), sendo que 35,8% (1136/3167) lactentes apresentaram sibilância ocasional (até dois episódios) e 20,1% (639/3167) apresentaram sibilância recorrente (três ou mais episódios). Sibilância recorrente grave (mais de 6 episódios) foi relatada em 8,7% lactentes (277/3167). Os fatores de risco independentes para apresentar de 3 a 6 episódios de sibilância foram: prematuridade (RR=1,46), tabagismo passivo (RR= 1,72, se menos de 10 cigarros/dia e RR=2,04. se mais de 10 cigarros/dia), frequentar a creche após os 6 meses (RR= 1,31), diagnóstico médico de rinite alérgica (RR= 1,52) e presença de carpete no domicílio (RR= 1,59). Os principais fatores de risco associados à sibilância grave foram: tabagismo passivo (RR= 2,89 para mais de 10 cigarros/dia), frequentar creche (RR= 2,43, se início até os 6 meses e RR: 1,49, se início após os 6 meses), resfriados nos 3 primeiros meses de vida (RR= 2,17), asma (RR= 1,50) e dermatite atópica na família (RR= 1,49) e diagnóstico de rinite alérgica (RR= 1,93). Lactentes brancos apresentaram prevalência menor de sibilância recorrente não grave (RR=0,68). Não houve associação entre o tempo de aleitamento materno e sibilância recorrente. Conclusões: Crianças nascidas em Ribeirão Preto apresentam alta prevalência de sibilância recorrente nos dois primeiros anos de vida. Nessa fase precoce da vida, medidas ambientais visando a diminuição da exposição à fumaça do cigarro e a prevenção de infeções virais poderiam resultar na redução dos casos de sibilância recorrente grave nesta população. / Objective: To evaluate the prevalence, severity and risk factors associated with recurrent wheezing in children in early years of life. Methods: Prospective cohort study of 3167 children born in Ribeirão Preto, São Paulo, in 2010, and evaluated for this study at 12-24 months of age. A standardized questionnaire with questions regarding maternal characteristics, gestational, perinatal and postnatal conditions, family and children allergy, occurrence of wheezing, number of wheezing episodes, daycare attendance, visits to emergency, medication use, diagnosis of pneumonia and hospitalizations was applied to caregivers . Associations between outcomes and the independent variables of interest were done through univariate analysis and adjusted log-binomial models. Relative risks (RR) and confidence intervals (CI) were calculated. Results: The prevalence of at least one episode of wheezing in the first two years of life was 56.3% (1785/3167), 35.8% (1136/3167) infants had occasional wheezing (up to two episodes) and 20,1% (639/3167) had recurrent wheezing (three or more episodes). Severe recurrent wheeze (more than 6 episodes) was reported in 8.7% infants (277/3167). The independent risk factors for presenting 3 to 6 episodes of wheezing were prematurity (RR = 1.46), passive smoking (RR = 1.72 for less than 10 cigarettes / day, RR = 2.04 for more than 10 cigarettes / day), daycare attendance after 6 months (RR = 1.31), medical diagnosis of allergic rhinitis (RR = 1.52) and the presence of carpet at home (RR = 1.59). The main risk factors associated with severe wheezing were passive smoking (RR = 2.89 for more than 10 cigarettes / day), daycare attendance (RR = 2.43 if was started before 6 months and RR=1.49, if started after 6 months), acute upper respiratory infections during the first 3 months of life (RR = 2.17), asthma (RR = 1.50) and atopic dermatitis in the family (RR = 1.49) and diagnosis of allergic rhinitis (RR = 1.93). White infants have a lower prevalence of non-severe recurrent wheezing (RR = 0.68). There was no association between duration of breastfeeding and recurrent wheeze Conclusions: Children born in Ribeirão Preto have a high prevalence of recurrent wheezing in the first two years of life. In this early stage of life, environmental measures to reduce the exposure to cigarette smoke and prevention of viral infections could result in the reduction of severe recurrent wheezing in this population.
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Associação entre polimorfismos em genes relacionados ao metabolismo de folato (RFC1, GCP2, MTHFR e MTHFD1) e alterações nas concentrações de folato, cobalamina e homocisteína em mulheres com história de abortos espontâneos recorrentes / Association between polymorphisms in genes related to folate metabolism (RFC1, GCP2, MTHFR and MTHFD1) and changes in the concentrations of folate, cobalamin and homocysteine in women with a history of recurrent miscarriagesGiusti, Kelma Cordeiro da Silva 16 October 2012 (has links)
O aborto espontâneo recorrente (AER) é caracterizado pela ocorrência de três ou mais abortos consecutivos e acomete 2-4% das mulheres em idade fértil. A etiologia está associada a vários fatores de risco, tais como anomalias uterinas, aberrações cromossômicas, autoimunidade, trombofilias, elevação na concentração de homocisteína (tHcy), porém cerca de 40% dos casos permanece sem causa definida. O metabolismo de unidades de carbono desempenha papel fundamental na disponibilidade de folato na célula, sendo essencial para o desenvolvimento placentário e fetal. Deficiência de vitaminas que regulam este metabolismo, como o ácido fólico, e polimorfismos em genes que codificam enzimas relacionadas ao metabolismo de folato (MTHFR, RFC1, GCP2 e MTHFD1) podem levar à redução das concentrações desta vitamina e ao aumento das concentrações de tHcy. Objetivo foi avaliar a associação entre polimorfismos em genes relacionados ao metabolismo do folato (RFC1, GCP2, MTHFR e MTHFD1) e o risco de se ter AER, bem como avaliar a associação entre estes polimorfismos e as alterações nas concetranções de folato, cobalamina e homocisteína. Foram constituídos três grupos: AER primário: 117 mulheres com AER e nenhum feto viável; AER secundário: 139 mulheres com AER e pelo menos um feto viável; e Controle: 264 mulheres sem história de aborto espontâneo. Nenhuma das mulheres estava grávida no momento da coleta do sangue. Amostras de sangue foram obtidas para dosagens bioquímicas (folato, Cbl, tHcy, entre outras), imunológicas e extração de DNA genômico. As genotipagens foram feitas por PCR-RFLP ou PCR em tempo real. As concentrações séricas de folato e Cbl foram maiores no AER primário e secundário (p<0,05). A distribuição dos genótipos de todos os polimorfismos foi semelhante nos três grupos. O aumento nas concentrações de folato sérico (OR: 1,05, 95% IC: 1,03 - 1,07, p<0,001), Cbl (OR: 1,00, 95% IC: 1,00 - 1,00, p= 0,016), tHcy (OR: 1,03, 95% IC: 0,97 - 1,11, p= 0,033) e T4 (OR: 1,02, 95% IC: 1,00 - 1,03, p= 0,006) e a presença de FAN reagente (1:160) (OR: 2,90, 95% IC: 1,25 - 6,75, p= 0,013) foram considerados fatores de risco para aborto primário. Para o aborto secundário, foram considerados fatores de risco o aumento nas concentrações de folato sérico (OR: 1,04, 95% IC: 1,02 - 1,05, p<0,001), Cbl (OR: 1,00, 95% IC: 1,00 - 1,00, p= 0,019) e tHcy (OR: 1,05, 95% IC: 1,00 - 1,09, p= 0,039), maiores idades (OR: 1,02, 95% IC: 0,98 - 1,06, p= 0,031), hábito de fumar (OR: 2,54, 95% IC: 1,41 - 4,60, p= 0,002) e ter maior IMC (OR:1,42, 95% IC: 1,07 - 1,88, p= 0,015). Os polimorfismos estudados não foram associados ao maior risco de se ter AER, quando analisados isoladamente, e também não foram associados a alterações nas concentrações séricas de folato, Cbl e tHcy, com exceção do genótipo MTHFR 677TT, cujas portadoras apresentaram maior concentração de tHcy, quando comparadas com as portadoras de genótipos 677CC e 677CT nos três grupos. As variáveis concentrações de folato, Cbl, tHcy e T4 e presença de FAN reagente foram associadas ao maior risco de se ter aborto primário. As variáveis idade, IMC, tabagismo, concentrações de folato, Cbl e tHcy foram associadas ao maior risco de aborto secundário. / The recurrent spontaneous abortion (RSA) is characterized by the occurrence of three or more consecutive miscarriages and affects 2-4% of women of childbearing age. The etiology is associated with several risk factors such as uterine abnormalities, chromosomal aberrations, autoimmunity, thrombophilia, increased concentration of homocysteine (tHcy). About 40% of cases remains unknown cause. The units of carbon metabolism plays an essential role in the availability of the cell folate, is essential for the placental and fetal development. A deficiency of the vitamins that regulate this metabolism, like folic acid, and polymorphisms in genes encoding enzymes related to folate metabolism (MTHFR, RFC1, and GCP2 MTHFD1) may lead to decreased concentrations of this vitamin and increased concentrations of tHcy. Objective was to evaluate the association between polymorphisms in genes related to folate metabolism (RFC1, GCP2, MTHFD1 and MTHFR) and the risk of having AER, and to evaluate the association between these polymorphisms and changes in concetranções folate, cobalamin, and homocysteine. Three groups were divided: AER primary: 117 women with RSA and no viable fetus, AER secondary: 139 women with RSA and at least one viable fetus and Control: 264 women with no history of miscarriage. None of the women was pregnant at time of blood collection. Blood samples were taken for biochemical (folate, Cbl, tHcy, etc.), immunological and genomic DNA extraction. The genotyping were carried out by PCR-RFLP or real time PCR. Serum concentrations of folate and Cbl were higher in groups 1 and 2 (p <0.05). The distribution of genotypes of MTHFR c.677C> T, MTHFR c.1298A> C, MTHFD1 c.1958G> A, RFC1 c.80G>GCP2 A and c.1561C> T was similar among the three groups. The increased concentrations of serum folate (OR: 1.05, 95% CI: 1.03 - 1.07, p <0.001), Cbl (OR: 1.00, 95% CI: 1.00 to 1.00, p = 0.016), tHcy (OR: 1.03, 95% CI: 0.97 to 1.11, p = 0.033) and T4 (OR: 1.02, 95% CI: 1.00 to 1.03, p = 0.006) and the presence of ANA (1:160) (OR: 2.90, 95% CI: 1.25 - 6.75, p = 0.013) were considered risk factors primary for abortion. For secondary abortion, were considered risk factors increased the concentrations of serum folate (OR: 1.04, 95% CI: 1.02 - 1.05, p <0.001), cobalamin (OR: 1.00, 95 % CI: 1.00 to 1.00, p = 0.019) and tHcy (OR: 1.05, 95% CI: 1.00 to 1.09, p = 0.039), higher age (OR: 1.02, 95% CI: 0.98 to 1.06, p = 0.031), cigarette smoking (OR: 2.54, 95% CI: 1.41 to 4.60, p = 0.002) and had a higher BMI (OR : 1,42,95% CI: 1.07 to 1.88, p = 0.015). The studied polymorphisms were not associated with increased risk of having RSA when analyzed separately, and were not associated with changes in serum folate, Cbl and tHcy, with the exception of the MTHFR 677TT genotype, whose patients had a higher concentration of total tHcy compared with those with 677CC and 677CT genotypes in the three groups. The variable concentrations of folate, Cbl, tHcy, and T4, presence of ANA and have been associated with increased risk for miscarriage primary. The variables age, BMI, smoking, concentrations of folate, Cbl and tHcy were associated with increased risk of secondary miscarriage.
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Deterministic and Flexible Parallel Latent Feature Models Learning Framework for Probabilistic Knowledge GraphGuan, Xiao January 2018 (has links)
Knowledge Graph is a rising topic in the field of Artificial Intelligence. As the current trend of knowledge representation, Knowledge graph research is utilizing the large knowledge base freely available on the internet. Knowledge graph also allows inspection, analysis, the reasoning of all knowledge in reality. To enable the ambitious idea of modeling the knowledge of the world, different theory and implementation emerges. Nowadays, we have the opportunity to use freely available information from Wikipedia and Wikidata. The thesis investigates and formulates a theory about learning from Knowledge Graph. The thesis researches probabilistic knowledge graph. It only focuses on a branch called latent feature models in learning probabilistic knowledge graph. These models aim to predict possible relationships of connected entities and relations. There are many models for such a task. The metrics and training process is detailed described and improved in the thesis work. The efficiency and correctness enable us to build a more complex model with confidence. The thesis also covers possible problems in finding and proposes future work.
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Modèles multiplicatifs du risque pour des événements successifs en présence d’hétérogénéité / Multiplicative intensity models for successive events in the presence of heterogeneityPénichoux, Juliette 17 September 2012 (has links)
L'analyse du risque de survenue d'événements récurrents est une motivation majeure dans de nombreuses études de recherche clinique ou épidémiologique. En cancérologie, certaines stratégies thérapeutiques doivent être évaluées au cours d'essais randomisés où l'efficacité est mesurée à partir de la survenue d'événements successifs marquant la progression de la maladie. L'état de santé de patients infectés par le VIH évolue en plusieurs étapes qui ont pu être définies par la survenue d'événements cliniques successifs.Ce travail de thèse porte sur les modèles de régression du risque pour l'analyse de la survenue d'événements successifs. En pratique, la présence de corrélations entre les temps d'attente séparant les événements successifs est une hypothèse qui peut rarement être écartée d'emblée. L'objectif de la thèse porte sur le développement de modèles de régression permettant d'évaluer une telle corrélation. Dans ce cadre, la méthode le plus souvent utilisée suppose que la corrélation entre les délais successifs a pour origine une hétérogénéité aléatoire, non observée, entre sujets. Le modèle correspondant définit le risque instantané individuel en fonction d'un terme aléatoire, ou « fragilité », de distribution gamma et dont la variance quantifie l'hétérogénéité entre sujets et donc la corrélation entre délais d'un même sujet. Cependant, l'utilisation de ce modèle pour évaluer l'ampleur des corrélations présente l'inconvénient de conduire à une estimation biaisée de la variance de la fragilité.Une première approche a été définie pour deux événements successifs dans une échelle de temps « par intervalles », c'est-à-dire où le risque est exprimé en fonction du temps écoulé depuis l'événement précédent. L'approche mise au point a été obtenue à partir d'une approximation du risque de second événement conditionnellement au premier délai dans un modèle à fragilité pour plusieurs distributions de fragilité. Une seconde approche a été définie en échelle de temps « calendaire », où le risque est exprimé en fonction du temps écoulé depuis le début du suivi du sujet. L'approche retenue a été obtenue à partir d'une approximation de l'intensité conditionnelle au passé dans un modèle à fragilité. Dans les deux échelles de temps, l'approche mise au point consiste à introduire une covariable interne, calculée sur le passé du processus, qui correspond à la différence entre le nombre d'événements observés pour le sujet sur la période passée, et le nombre attendu d'événements pour ce sujet sur la même période compte tenu de ses covariables externes. Une revue de la littérature des études de simulations a montré que le cas d'une hétérogénéité dans la population face au risque d'événement était souvent envisagé par les auteurs. En revanche, dans beaucoup d'études de simulations, le cas d'un risque dépendant du temps, ou d'une dépendance entre événements, n'étaient pas considérés. Des études de simulations ont permis de montrer dans les deux échelles de temps considérées un gain de puissance du test mis au point par rapport au test d'homogénéité correspondant au modèle à fragilité gamma. Ce gain est plus marqué en échelle de temps par intervalles. Par ailleurs, dans cette échelle de temps, le modèle proposé permet une amélioration de l'estimation de la variance de la fragilité dans le cas d'une hétérogénéité faible ou modérée, plus particulièrement pour de petits échantillons.L'approche développée en échelle de temps par intervalles a été utilisée pour analyser les données d'une cohorte de patients infectés par le VIH, montrant une corrélation négative entre le délai entre infection et première manifestation mineure d'immunodéficience et le délai entre première manifestation mineure d'immunodéficience et stade SIDA déclaré. / The risk analysis for the occurrence of recurrent events is a major concern in many clinical research studies or epidemiological studies. In the field of oncology, therapeutic strategies are evaluated in randomised clinical trials in which efficacy is assessed through the occurrence of sequential events that define the progression of the disease. In HIV-infected patients, the infection evolves in several stages that have been defined by the occurrence of successive clinical events. The frame of this work is the regression models for the risk of multiple successive events. In practice, the hypothesis of existing correlations between the inter-event times cannot be a priori discarded. The aim of this work is to develop a regression model that would assess such correlations. In this setting, the most common method is to assume that correlations between inter-event times are induced by a random, unobserved heterogeneity across individuals. The corresponding model defines the individual hazard as a function of a random variable, or " frailty ", assumed to be gamma-distributed with a variance that quantifies the heterogeneity across individuals and incidentally the correlations between inter-event times. However, the use of this model when evaluating the correlations has the drawback that it tends to underestimate the variance of the frailty.A first approach was proposed for two sequential events in a "gap-timescale", in which the risk is defined as a function of the time elapsed since the previous event. The proposed method was derived from an approximation of the risk of second event given the first time-to-event in a frailty model for various frailty distributions. Another approach was defined in "calendar-time", in which the risk is expressed as a function of the time elapsed since the beginning of the subject's follow-up. The proposed method was derived from an approximation of the intensity conditional on the past in a frailty model. In both timescales, the method that was developed consists in including in the model an internal covariate, that is calculated on the history of the process, and that corresponds to the difference between the observed number of events and the expected number of events in the past period given the individual's other covariates.A review of the literature involving simulation studies showed that when defining the generation processes, most authors considered the case of heterogeneity in the population. However, in many simulation studies, only constant hazards are considered, and no event-dependence is introduced. Simulations studies showed that in both timescales, the test of the effect of the internal covariate in the proposed model proved more powerful that the usual test of homogeneity in the gamma frailty model. This gain of power is more noticeable in gap-time. Additionally, in this timescale, the proposed model provides a better estimation of the variance of the frailty when heterogeneity is low or moderate, more particularly in small samples.The method developed in gap-time was used to analyse data from a cohort of HIV-infected patients. It showed a negative correlation between the time from infection to first minor manifestation of immunodeficiency and the time from first minor manifestation of immunodeficiency to AIDS. The method developed in calendar-time was used to study the occurrence of repeated progressions and severe toxicities in a clinical trial for patients with advanced colorectal cancer. In this example, the method corroborated the results obtained with a gamma frailty model which showed a significant heterogeneity.
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Avaliação da taxa de metilação do DNA em região promotora e de vitaminas e citocinas em mulheres com história de abortos recorrentes / Investigation of DNA methylation rate in promoter region and vitamins and cytokines in women with a history of recurrent miscarriage.Monteiro, Nathalia Sierra 20 March 2014 (has links)
O aborto espontâneo recorrente (AER) caracteriza-se pela ocorrência de três ou mais abortos consecutivos espontâneos até a 20ª semana de gestação. É uma condição patológica multifatorial, em que alterações morfológicas uterinas, distúrbios endócrinos, alterações no cariótipo, polimorfismos genéticos relacionados aos genes envolvidos no metabolismo da homocisteína, hemostasia, infecções, autoanticorpos e o processo inflamatório podem contribuir para a ocorrência de AER. O estado fisiológico do endométrio é essencial para a implantação do embrião no útero durante a gestação. Na interface materno-fetal, há uma modulação de citocinas, necessária para o estabelecimento da angiogênese e desenvolvimento da placenta. Um desequilíbrio entre as citocinas pode diminuir a tolerância ao feto e ocasionar rejeição fetal. A concentração de citocinas pode ser modificada por conta de uma diminuição na expressão de alguns genes, e esta pode ser regulada pelo seu estado de metilação sítio-específica. A metilação do DNA é um mecanismo epigenético de regulação gênica, e que corresponde à incorporação de grupos metila em ilhas CpG localizadas próximas às regiões promotoras de genes humanos, e isso pode ser importante na avaliação do risco de complicações gestacionais. Além disso, o estado nutricional de vitaminas foi relacionado a alterações no padrão de metilação de alguns genes. Os objetivos deste trabalho foram avaliar as concentrações dos mediadores inflamatórios em mulheres com aborto e em grupo controle, verificar correlações entre as concentrações de vitaminas, homocisteína total e taxa de metilação do DNA, verificar correlações entre concentração de citocinas e taxa de metilação do DNA e determinar odds ratio (IC 95%) de ter aborto em modelos multivariados. Foram incluídas 253 mulheres com história de aborto recorrente e 264 mulheres saudáveis (controle). O DNA foi extraído de leucócitos de sangue periférico para o estudo de metilação. Foram separadas alíquotas de soro e plasma para dosagem de vitaminas, metabólitos e citocinas. Não foram encontradas diferenças nas taxas de metilação do DNA entre os grupos aborto e controle. A citocina TNFα está aumentada nos grupos de aborto em comparação ao controle. A taxa de metilação do DNA no gene IFNG foi correlacionada inversamente às concentrações de folato sérico e citocina IFNγ no grupo controle. E as concentrações de IL10 foram inversamente correlacionadas à taxa de metilação do DNA nos grupos de aborto secundário e controle. Neste trabalho, verificou-se que as vitaminas e as citocinas influenciam na taxa de metilação do DNA do gene IFNG e a citocina pró-inflamatória TNFα apresenta-se aumentada em mulheres com história de aborto. / Recurrent spontaneous abortion (RSA) is characterized by the occurrence of three or more consecutive spontaneous abortions until the 20th week of gestation. It is a multifactorial pathological condition in which morphological uterine, endocrine disorders, changes in the karyotype genetic polymorphisms related to genes involved in homocysteine metabolism, infection, autoimmunity and inflammatory processes may contribute to the occurrence of RSA. The physiological state of the endometrium is essential for embryo implantation in the uterus during pregnancy. In maternal-fetal interface, there is a modulation of cytokines necessary for the establishment and development of placental angiogenesis. An imbalance between cytokines can decrease tolerance to fetus and cause fetal rejection. Concentration of cytokines may be modified due to a decrease in the expression of genes related to some of these cytokines that can be regulated by DNA methylation, which is an epigenetic mechanism of gene regulation and which corresponds to the incorporation of groups Methyl CpG islands located near the promoter regions of human genes, and this may be important in assessing the risk of pregnancy complications. In addition, the nutritional status of vitamins was associated with changes in the methylation pattern of certain genes. The aims of this study were to determine the concentrations of inflammatory mediators in women with abortion and the control group, examine correlations between concentrations of vitamins, total homocysteine and DNA methylation rate, examine correlations between cytokine concentration and DNA methylation and determine odds ratio (95% CI) of having abortion in multivariate models. We included 253 women with a history of recurrent miscarriage and 264 healthy women (control). DNA was extracted from peripheral blood leukocytes for the study of methylation. Serum and plasma aliquots were used for determination of vitamins, metabolites and cytokines. There were no differences in rates of DNA methylation between control and abortion groups. The cytokine TNFα is increased in abortion groups compared to the control. DNA methylation rate in gene IFNG was inversely correlated with serum folate and serum cytokine IFNγ in the control group. Also IL10 concentrations were inversely correlated to DNA methylation rate in groups of miscarriage and secondary control. In this work, it was found that vitamins and cytokines influence DNA methylation rate in the promoter region and are different in the study and control groups.
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Associação entre os polimorfismos nos genes da Transcobalamina II (TCN2 c.776C>G e TC2 c. 67A>G) e da metilenotetraidrofolato redutase (MTHFR c.677C>T) e o risco de ter abortos espontâneos recorrentes / Association between polymorphisms in the transcobalamin II (TCN2 c.776C> G and c TC2. 67A> G) and methylenetetrahydrofolate reductase (MTHFR c.677C> T) and the risk of having recurrent miscarriages.Lazaro, Robson José 19 August 2013 (has links)
O aborto espontâneo recorrente (AER) é definido pela ocorrência de três ou mais abortos espontâneos consecutivos com idade gestacional de até 20 semanas. O AER é um evento multifatorial, tem um índice de elucidação da causa na ordem de 50% e, mesmo com os avanços da medicina diagnóstica ainda assim 40% dos casos permanecem com sua causa desconhecida. O crescimento fetal é totalmente dependente do aporte de nutrientes oirundos da mãe, dentre esses nutrientes a cobalamina e o ácido fólico desempenham um papel fundamental para a viabilidade fetal. O objetivo geral deste estudo foi investigar se existe associação entre polimorfismos em genes relacionados ao metabolismo da cobalamina (MTHFR c.677C>T, TCN2 c. 776C>G e TCN2 c. 67A>G), e o aborto espontâneo recorrente. Os objetivos específicos deste estudo foram: 1 determinar se os polimorfismos MTHFR c. 677C>T, TCN2 c. 776C>G e TCN2 c. 67A>G estão associados ao aborto primário e secundário. 2 - Avaliar se os genótipos dos polimorfismos estudados estão relacionados com as concentrações séricas de cobalamina, folato e homocisteína total em mulheres com aborto espontâneo recorrente. Foram incluídas 256 mulheres com história de abortos espontâneos recorrentes, provenientes do Ambulatório de Obstetrícia da Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da USP e 264 mulheres saudáveis, sem história de aborto espontâneo e que tenham tido pelo menos duas gestações normais (grupo controle), pareadas segundo as idades. Foram colhidas amostras de sangue para a realização das dosagens bioquímicas, hormonais e das vitaminas e também para a realização das genotipagens dos polimorfismos por meio de PCR-RPFL (MTHFR c.677C>T , TCN c.776C>G e c. 67A>G). As dosagens bioquímicas e hormonais apresentaram resultados dentro dos limites de variação do normal. Quanto as concentrações de folato e cobalamina, houve diferença estatística significante entre os grupos p<0,05. As frequências dos genótipos e alelos para os polimorfismos estudados comparadas entre os grupos abortos primário, aborto secundário e grupo controle não apresentaram diferença estatística significante. Optamos a seguir por dividir o grupo de estudo entre abortos primários, onde não existe história de feto viável, e secundário neste caso onde há história de feto viável. Desta forma foram refeitas as análises estatísticas entre os grupos e encontramos diferença estatísticamente significante p<0,05 quando confrontamos os genótipos do polimorfismo TCN c.776C>G entre o grupo primário e o grupo controle. Em conclusão, quando comparamos as frequência dos genótipos e alelos em conjunto não apresentaram associação com o AER. Quando comparado separadamente o grupo de aborto primário e grupo controle houve diferença estatística significante associando o polimorfismo TCN2 c.776C>G ao AER primário. / The recurrent spontaneous abortion (RSA) is defined by the occurrence of three or more consecutive miscarriages with gestational age up to 20 weeks. The AER is a multifactorial event, has an index of elucidating the cause of around 50% and, even with advances in diagnostic medicine still remain 40% of cases with a known cause. Fetal growth is totally dependent on the supply of nutrients from the mother oirundos among these nutrients cobalamin and folic acid play a key role in fetal viability. The aim of this study was to investigate whether there is an association between polymorphisms in genes related to metabolism of cobalamin (MTHFR c.677C> T, c TCN2. 776c> G and c TCN2. 67A> G), and recurrent miscarriage. The specific objectives of this study were: 1 determine whether MTHFR c. 677C> T, TCN2 c. 776c> G and c TCN2. 67A> G are associated with abortion primary and secondary. 2 - Assess whether the genotypes studied polymorphisms are associated with serum concentrations of cobalamin, folate and total homocysteine in women with recurrent spontaneous abortion. We included 256 women with a history of recurrent miscarriages, from the Clinic of Gynecology, Obstetrics, Hospital das Clinicas, Faculty of Medicine, USP and 264 healthy women with no history of miscarriage and have had at least two normal pregnancies (group control), matched according to age. Blood samples were collected to perform the biochemical, hormonal and vitamins and also to perform the genotyping of polymorphisms by PCR-RPFL (MTHFR c.677C> T, TCN c.776C> G and c. 67A> G). The biochemical and hormonal results presented within the limits of normal variation. As the concentrations of folate and cobalamin, statistically significant difference between groups p <0.05. The frequencies of genotypes and alleles for the polymorphisms studied compared between groups abortions primary, secondary and abortion control group showed no statistically significant difference. We chose then to divide the study group between primary abortions where there is a history of viable fetus, and secondary in this case where there is a history of viable fetus. Thus were repeated statistical analyzes between groups and found statistically significant difference p <0.05 when confronted TCN genotypes of polymorphism c.776C> G between the primary group and the control group. In conclusion, when comparing the frequency of genotypes and alleles together apresntaram no association with AER. When compared separately the group of abortion primary and control group was statistically significant associated polymorphism TCN2 c.776C> G the primary AER.
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Polymeric airway mucins in equine recurrent airway obstructionWilliams, Adele January 2014 (has links)
In healthy airways, mucus forms part of the innate immune response protecting the respiratory epithelium from damage by pathogens and environmental debris (Rose and Voynow, 2006). Conversely, in many respiratory diseases, mucus becomes part of the airway disease pathology. Mucus hypersecretion along with reduced clearance can cause blockage of the small airways, impairing gas exchange, promoting inflammation and becoming a culture medium for bacterial colonisation (Thornton et al., 2008). Recurrent airway obstruction (RAO) is a common yet poorly understood equine chronic respiratory disease where such altered mucus properties and clearance have been identified as major factors in the disease pathology (Davis and Rush, 2002; Gerber et al., 2000; Kaup et al., 1990; Robinson, 2001). The gel-forming mucins are largely responsible for the transport properties of mucus. The major equine airway gel-forming mucin in health is Muc5b and to a lesser extent Muc5ac; produced in specialised respiratory epithelial goblet cells and sub-mucosal glands (Rousseau et al., 2011b). Changes in mucin relative and net amounts and their macromolecular properties and interactions have been attributed to the altered physical properties of airway mucus in airways disease (Groneberg et al., 2002a; Jefcoat et al., 2001; Kirkham et al., 2002; Robinson et al., 2003; Sheehan et al., 1995).The project investigates the biochemical properties of mucins present in mucus from healthy horses and horses with RAO. This project identifies the anatomical presence of mucin-producing goblet cells and glands in fixed tissues from the respiratory tracts of healthy horses and subsequently examines mucin-production sites in respiratory tracts from horses with RAO. Finally the project investigates a methodology for the study of mucin production in airway cells harvested from live horses suffering from RAO.Our investigations confirmed that horses with RAO have more endotracheal mucus than healthy controls, and that Muc5b is the predominant mucin with Muc5ac also present in RAO horse mucus, both during symptomatic disease and when horses are asymptomatic. Mucins are produced in epithelial goblet cells and sub-mucosal glands dispersed throughout the length and circumference of the equine trachea and bronchi. Goblet cell hyperplasia occurs in symptomatic exposed RAO horse airways, although goblet cells are smaller than in asymptomatic RAO horse airways. Exposure to a dusty stable environment is associated with more goblet cells per length of bronchial compared to tracheal epithelium in all horses. RAO horses have larger sub-mucosal glands containing more mucin than control horses. Primary epithelial cell cultures grown at an air liquid interface are an alternative approach to study equine airway mucus, although the use of this culture system is in its early stages. We have developed novel ways to harvest equine airway epithelial cells (tracheal brushing) and shown it is possible to freeze cells collected via tracheal epithelial brushing in 20 % FBS and then culture to ALI at a later date.
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Modelo de regressão para um processo de renovação Weibull com termo de fragilidade / Regression model for a Weibull renewall process distribution with a frailty efectJosé Carlos Fogo 03 August 2007 (has links)
Processsos de renovação são um caso especial de processos pontuais envolvendo eventos recorrentes nos quais um item ou unidade, após a ocorrência de uma falha, é recolocado na mesma condição de novo. Devido a essa propriedade os tempos entre ocorrências para um processo de renovação são independentes e a sua função intensidade é dada pela função de risco. Fatores que interferem nos tempos de recorrência de unidades distintas, ou indivíduos, e que não são observados, podem ser modelados com a inclusão de um termo de fragilidade no modelo. Neste trabalho é apresentado o desenvolvimento de um modelo de regressão para um processo de renovação com tempos entre ocorrências com distribuição de Weibull. Na modelagem foi considerada, ainda, a presença de censuras e a inclusão de um termo de fragilidade para explicar a relação existente entre os tempos de recorrências de uma unidade. A metodologia é desenvolvida para o caso em que várias unidades são acometidas por eventos recorrentes. Nas simulações realizadas foram analisadas as probabilidades de cobertura empíricas do intervalo de confiança normal assintótico e também o comportamento das variâncias dos estimadores. A presença de censuras na amostra inflacionou as variâncias dos estimadores de máxima verossimilhança além de produzir estimativas viciadas para um dos parâmetros da regressão, sendo que o vício do estimador foi corrigido por meio de um processo "bootstrap". Na modelagem sem termo de fragilidade, os resultados das análises das probabilidades de cobertura empírica dos intervalos de confiança assintóticos mostraram uma boa aproximação com os valores esperados, mas com certos cuidados a serem tomados, especialmente nos procedimentos baseados na simetria das distribuições empíricas. A inclusão de um termo de fragilidade na modelagem, por sua vez, causou uma perturbação na estimação máxima verossimilhança com um aumento nas variâncias dos estimadores diretamente associados à variabilidade do termo de fragilidade. Além disso, as coberturas empíricas dos intervalos de confiança assintóticos foram, na grande maioria superestimadas, com resultados satisfatórios apenas para o parâmetro de forma da distribuição Weibull. / Renewal Processes are a special case of point processes involving recurrent events in which a unit, after a failure, is restored to the like new condition. Due to that property the times between occurrences for a renewal process are independent and its intensity function is given by the hazard function. Random factors not observed, that afects the recurrence times of the units, can be explained by a frailty term added in the model. In this work a regression model is presented for a renewal process with Weibull distribution for the times between occurrences. The modeling considers censored times and a frailty variable to explain the relationship among the recurrence times of a unit. The methodology was developed for the situation where several units are submitted by recurrent events. The empirical probabilities of coverage of the asymptotic normal confidence interval and the behavior of the variances of the estimators were analyzed in the simulations performed. The presence of censures in the sample inflated the variances of the maximum likelihood estimators besides to produce biased estimates for the regression parameters. The bias of the estimator was corrected by "bootstrap" procedure. The analysis of the probability of empirical coverage of the asymptotic confidence intervals, without frailty, presented a good approximation to the nominal values, but some observations about procedures have to be made on the symmetry of the empirical distributions. The frailty term incorporated at the modeling disturbed the maximum likelihood estimation increasing estimators' variability, directly associated to the variance of the fragility term. In the most of the cases, the empirical coverages of the asymptotic confidence intervals were overestimated, with satisfactory results just for the shape parameter of the Weibull distribution.
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Staphylococcus aureus em tonsilas de pacientes com faringotonsilite aguda recorrente: prevalência, perfil de suscetibilidade e caracterização genotípica / Staphylococcus aureus in the tonsils of patients with acute recurrent pharyngotonsillitis: prevalence, susceptibility profile and genotypic characterizationCavalcanti, Veraluce Paolini 17 October 2013 (has links)
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Previous issue date: 2013-10-17 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The bacterial pharyngotonsillitis are infections of the upper airways that occurs predominantly in children and adolescents. Due to the composition of the oral microbiota is difficult to clarify the role of each organism in the etiology of the disease. The presence of bacteria that produce beta-lactamase interferes with the effectiveness of beta-lactam antibiotics, the most commonly drug used in treatment of these infections, promoting the recurrence of the disease. S. aureus is one of the most common pathogen in the etiology of tonsillitis and its relevance is due to the ability of antimicrobial resistance and persistence in the tissues of the tonsils. Tonsillectomy is indicated in cases of recurrent tonsillitis after several failures in the antibiotic terapy. The aim of this study was to determine the prevalence of S. aureus in the tonsils of patients undergoing tonsillectomy, in a teaching hospital in Goiânia, the antimicrobial susceptibility profile and the genetic characterization of isolates. Tonsils obtained from 123 patients were processed, the microorganisms identified and submitted to antibiogram by conventional techniques. The isolates that presented cefoxitin resistance were submitted to tests to determine the minimum inhibitory concentration - MIC for oxacillin and to detect the presence of the mecA gene. All isolates were subjected to PCR for detection of Panton-Valentine leukocidin gene and to PFGE to determine the genetic similarity among them. It was identified 60 S. aureus isolates from 49 patients (39.8%). There were no significant difference in prevalence by sex and, the average age of male patients was lower (8.2 years) (p<0.001) than the female patients (15.3 years). Nine out 49 patients(18.4%) presented two or more different S. aureus isolates. The isolates presented resistance of 85.0%, 10.0%, 15.0%, 3.3%, 10.0%, 3.3%, 18.3% and 8.3% to penicillin, amoxicillin + ácido clavulânico, cefoxitin, ceftriaxone, erythromycin, trimethoprim/sulfamethoxazole, ciprofloxacin and tetracycline, respectively. All isolates were sensitive to linezolid and rifampin. Six erythromycin-resistant isolates (10.0%) showed inducible resistance (MLSbi) to clindamycin and quinupristin/dalfopristin. Eight isolates (13.3%) were resistant to three or more classes of antimicrobials. Despite the resistance to cefoxitin be considered a marker of the presence of the mecA gene only in two resistant isolates it has been found,
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suggesting that the cefoxitin resistance should be mediated by other mechanisms, such as the overproduction of beta-lactamases. None of these isolates showed resistance to more than two classes of antimicrobials. Among the sixty S. aureus isolates, only carried the gene encoding the Panton-Valentine leukocidin. This isolate presented resistance to five classes of antimicrobials and phenotype D. PFGE analysis grouped 36 (60,0%) of 60 isolates in 10 clusters (>80% similarity), since no one specific clone was associated with colonization of the tonsils. It was observed different patients carrying S. aureus isolates genetically identical or with a high level of similarity (>80%), suggesting in these cases, a common origin. The high prevalence of S. aureus in tonsils suggests an ability to colonize the surface and/or the persistence in the tissues of the tonsils. The isolation of MDR bacteria can promote cross-resistance to other bacteria commonly associated with recurrent tonsillitis. The results point to change the paradigm of diagnosis and treatment of recurrent tonsillitis in order to enable the correct use of antimicrobials to reduce the recurrence which is the main cause of tonsillectomy. / As faringotonsilites bacterianas são infecções das vias aéreas superiores que ocorrem predominantemente em crianças e adolescentes. Devido à composição da microbiota oral é difícil o esclarecimento da participação de cada microrganismo na etiologia da doença. A presença de bactérias produtoras de β-lactamases interfere na eficácia de antimicrobianos β-lactâmicos, os mais utilizados no tratamento destas infecções, favorecendo a recorrência da doença. S. aureus é um dos patógenos mais frequentes na etiologia das tonsilites e sua relevância se deve à capacidade de resistência aos antimicrobianos e à persistência nos tecidos internos das tonsilas. A tonsilectomia é indicada nos casos de tonsilite recorrente após várias falhas na antibioticoterapia. O objetivo deste trabalho foi determinar a prevalência de S. aureus em tonsilas de pacientes submetidos à tonsilectomia, em um hospital escola de Goiânia; o perfil de suscetibilidade aos antimicrobianos e a caracterização genética dos isolados. Tonsilas obtidas de 123 pacientes foram processadas, os microrganismos identificados e submetidos ao antibiograma por técnicas convencionais. Nos isolados resistentes à cefoxitina, foi realizada a determinação da concentração inibitória mínima - CIM para oxacilina e a detecção da presença do gene mecA por PCR. Todos os isolados foram submetidos à PCR para detecção da leucocidina Panton-Valentine e ao PFGE para determinação da similaridade genética. Foram identificados 60 isolados de S. aureus de 49 pacientes (39,8%). Não houve diferença significativa da prevalência por sexo e a média de idade dos pacientes do sexo masculino foi menor (8,2 anos) (p<0,001) do que das pacientes (15,3 anos). Em nove (18,4%) dos 49 pacientes houve a identificação de dois ou mais isolados diferentes de S. aureus. Os isolados apresentaram resistência de 85,0%, 10,0%, 15,0%, 3,3%, 10,0%, 3,3%, 18,3% e 8,3% para penicilina, amoxacilina + ácido clavulânico, cefoxitina, ceftriaxona, eritromicina, sulfametoxazol/trimetoprim, ciprofloxacina e tetraciclina respectivamente. Todos os isolados foram sensíveis à linezolida e rifampicina. Seis isolados (10,0%) resistentes à eritromicina apresentaram fenótipo de resistência induzível (MLSbi) à clindamicina e quinupristina/dalfopristina. Oito isolados (13,3%) foram resistentes a três ou mais classes de antimicrobianos. Apesar da resistência à cefoxitina ser considerada o
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marcador da presença do gene mecA, somente em dois isolados resistentes, o mesmo foi detectado sugerindo que a resistência à cefoxitina pudesse ser mediada por outro mecanismo, como a hiperprodução de β-lactamases. Nenhum desses isolados apresentou resistência a mais de duas classes de antimicrobianos. Dos 60 S. aureus isolados, somente um apresentou o gene que codifica a leucocidina Panton-Valentine. Neste isolado ainda foi observada resistência a cinco classes de antimicrobianos e fenótipo D. A análise por PFGE agrupou 36 (60,0%) dos 60 isolados em 10 clusters (>80% similaridade), não sendo detectado um clone específico associado à colonização das tonsilas. Porém observamos pacientes diferentes portando S. aureus geneticamente idênticos ou com alto grau de similaridade (>80%), sugerindo nestes casos, uma origem comum. A alta prevalência de S. aureus nas tonsilas sugere uma capacidade de colonização da superfície e/ou persistência nos tecidos internos das tonsilas. O isolamento de bactérias MDR pode favorecer resistência cruzada de outras bactérias comumente associadas à tonsilite recorrente. Os resultados apontam para mudança no paradigma de diagnóstico e tratamento de tonsilites recorrentes com vistas a viabilizar o uso correto de antimicrobianos e diminuir a recorrência que é a principal causa de tonsilectomia
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Manifestações bucais em pacientes com hipogamaglobulinemia / Oral manifestations in patients with hypogammaglobulinemiaKarin Sá Fernandes 01 July 2010 (has links)
A hipogamaglobulinemia é uma alteração da imunidade humoral caracterizada por baixos níveis séricos de anticorpos podendo ter causas primárias e secundárias. Estes pacientes apresentam uma susceptibilidade a infecções bacterianas de repetição ou crônicas, principalmente do trato respiratório. Além disso, há alta prevalência de doenças gastrointestinais infecciosas e inflamatórias, hepatite C, doenças auto-imunes, doenças linfoproliferativas e granulomatosas. Ainda que a doença seja conhecida desde 1954 há poucos trabalhos na literatura sobre manifestações bucais nestes pacientes. Alguns estudos sugerem uma maior prevalência de lesões liquenóides, doença periodontal, candidíase pseudomembranosa, úlcera aftosa recorrente e hipoplasia de esmalte. Desta forma, o objetivo deste trabalho foi avaliar a prevalência das manifestações e alterações bucais, e caracterizar a saúde bucal de pacientes com hipogamaglobulinemias e correlacioná-las com o estado imunológico do paciente, comparativamente a um grupo de pacientes saudáveis. Para tanto avaliamos 100 pacientes com hipogamaglobulinemias atendidos no Ambulatório de Imunologia e Alergia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo e 93 pacientes normorreativos da Clínica Odontológica da Faculdade de Odontologia da Universidade de São Paulo, sendo realizado exame clínico bucal, anamnese e compilação de exames laboratoriais recentes. Do total de pacientes com hipogamaglobulinemias, 59 pacientes apresentaram alguma alteração bucal, sendo as mais frequentes lesões de cárie (21), hipoplasia de esmalte (21), gengivite (18), periodontite (8), boca seca (6), língua geográfica (5) e úlcera aftosa recorrente (2). Vinte e sete pacientes apresentaram queixas de úlcera aftosa recorrente com frequência. Dos 93 pacientes do grupo controle, 84 (90,3%) apresentaram alguma alteração bucal, sendo as mais frequentes lesões de cárie (66), gengivite (31), periodontite (44) e candidíase (3). Dezoito pacientes apresentaram queixas de úlcera aftosa recorrente com freqüência. Concluímos que os pacientes com hipogamaglobulinemias, apesar de apresentarem diminuição das imunoglobulinas do sangue, e alguns pacientes apresentarem uma diminuição de células da imunidade celular, não se encontrou relação positiva entre a incidência de cárie e IgA, doença periodontal e IgA e doença periodontal e CD4. / The hypogammaglobulinemia is an alteration in humoral immunity characterized by low levels of antibodies may have primary and secondary causes. These patients have a susceptibility to recurrent bacterial infections or chronic diseases, mainly respiratory tract. Moreover, there is a high prevalence of infectious and inflammatory gastrointestinal diseases, hepatitis C, autoimmune diseases, lymphoproliferative diseases and granulomatous disease. Although the disease is known since 1954 there are few available studies on oral manifestations in these patients. Some studies suggest a higher prevalence of lichenoid lesions, periodontal disease, pseudomembranous candidiasis, recurrent aphthous ulcer and enamel hypoplasia. Thus, the objective was to assess the prevalence of manifestations diseases and to characterize the oral health of patients with hypogammaglobulinemia and correlate with the immune status, compared with healthy patients. For that evaluated 100 patients with hypogammaglobulinemia in the Outpatient Immunology and Allergy Hospital of the Faculty of Medicine, University of São Paulo and 93 healthy patients of School of Dentistry, University of São Paulo, and was conducted oral clinical examination, medical history and compilation of recent laboratory tests. Of all patients with hypogammaglobulinemia, 59 patients showed abnormalities of the mouth, with 21 patients exhibited caries, 21 enamel hypoplasia, 18 gingivitis, 8 periodontitis, 6 dry mouth, 5 geographic tongue and 2 recurrent aphthous ulcer. Twenty-seven patients complained of frequent recurrent aphthous ulcer. Of the 93 control group patients, 84 (90.3%) showed abnormalities, being the most frequent caries (66), gingivitis (31), periodontitis (44) and candidiasis (3). Eighteen patients complained of recurrent aphthous ulcers frequently. We conclude that patients with hypogammaglobulinemia, despite showing decreased blood immunoglobulins, and some patients had a decrease of cells in cellular immunity, we did not find a positive relationship between the incidence of caries and IgA, IgA and periodontal disease and periodontal disease and CD4.
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