Functional Analysis of DNA Demethylation - During IL4/GM-CSF-driven Differentiation of Human Monocytes

Epigenetic processes, such as DNA (de)methylation and chromatin remodeling are fundamental for hematopoietic cell differentiation and lineage specification. Hence, their dysregulation is associated with many hematological malignancies. In this thesis, the analyses were focused on DNA demethylation processes during monocyte (MO) to immature dendritic cell (iDC) differentiation in the presence of the cytokines IL4 and GM-CSF. Due to the absence of cell proliferation in this system, we were able to investigate TET-mediated active demethylation events occurring in a replication-independent context. In hematopoietic cells, comprising MO and MO-derived cells, the TET2 enzyme is the main hydroxylase catalysing the initial oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) and likely the remaining oxidative steps as well. In this thesis, the TET2 gene was transiently knocked-down in MO using a well-established siRNA-mediated approach and its functional consequences during iDC differentiation were assessed. Overall, TET2 depletion was associated with very mild effects on iDC differentiation, transcriptional programs and chromatin remodeling processes. Nevertheless, the data was reproducible among donors and corroborated the importance of TET2-mediated active DNA demethylation processes during MO differentiation. Based on preliminary genome-wide methylation analyses in MO and iDCs, 7610 iDC-specific differentially methylated regions (DMRs) were identified. These regions were characterized by a progressive active DNA demethylation (5hmC enrichment) and an increase in chromatin accessibility. Since we were mostly interested on differentiation-associated processes, the analyses were centered on transcription factors (TFs) enriched across DMRs and strongly induced in iDCs, such as IRF4 and EGR2. Consequently, both TFs were individually and transiently knocked-down in MO and their effects on iDC differentiation and associated epigenetic processes were determined. IRF4 depletion prevented the differentiation of iDC, and instead cells acquired a macrophage-like morphology confirming previous mouse work244. Interestingly, we found that IRF4 might be involved in open chromatin at its binding sites regardless of changes in DNA demethylation, as reflected by the reduced chromatin accessibility and the minor effects on DNA methylation upon its depletion. Remarkably, this work is the first to describe an essential role of EGR2 in IL4/GM-CSF-mediated MO differentiation. Indeed, data showed a strong impact of EGR2 depletion on cell morphology and viability as well as profound changes in iDC transcriptional programs. Besides its importance on MO biology, EGR2 is implicated in active DNA demethylation and chromatin remodeling processes as indicated by iDC DMRs that remained methylated and failed to gain accessibility upon EGR2-silencing. Notably, the presence of a methylation footprint in the EGR2 motif associated with its ability to bind methylated DNA, suggest that the epigenetic pioneer EGR2 can target de novo demethylation processes at its transient and stable binding sites. In fact, co-immunoprecipitation data showed an interaction between EGR2 and TET2, emphasizing the EGR2 role in targeting the DNA demethylation machinery. In summary, this thesis provides new insights into dynamic epigenetic changes through IL4/GM-CSF-mediated MO differentiation. Accordingly, we identified key regulators on MO biology and differentiation-associated epigenetic processes, specifically IRF4 and EGR2. Importantly, EGR2 was found to recruit TET2 to its binding sites even before chromatin opening or TF binding detection, suggesting that at certain iDC DMRs active DNA demethylation and chromatin accessibility changes are uncoupled. In addition, this work demonstrated that DNA methylation-spikes (identified in EGR2 as well as other consensus motifs of TFs) are cell type-specific and protected from demethylation by bound key epigenetic pioneer factors

Prática da episiotomia e fatores maternos e neonatais relacionados

A episiotomia trata-se de uma incisão cirúrgica realizada no momento da expulsão do concepto. O objetivo deste estudo foi avaliar o uso da episiotomia e sua associação com as alterações maternas e neonatais em duas maternidades públicas. A população constituiu-se de parturientes submetidas ao parto normal, no período de junho de 2009 a maio de 2010, mediante revisão dos prontuários. Foram analisados 1.129 prontuários. A episiotomia foi utilizada em 57,55% (n=636) de todos os partos normais e em 83,7% (n=325) dos partos de primíparas. A associação entre o uso da episiotomia e a primiparidade é estatisticamente significante (p<0,001). Os dados sugerem a associação da episiotomia e aumento do risco de lacerações graves (p<0,001). O emprego da episiotomia mostrou-se semelhante nas duas maternidades. Os resultados deste estudo ratificam o uso indiscriminado da episiotomia e apontam para a necessidade de propor estratégias para reduzir o emprego dessa técnica

Infant-direct speech and mother-infant attention in depressed and nondepressed mothers

Postpartum depression (PPD) is associated with disturbances in many aspects of mother-infant interaction.  We compared the content of the infant-directed speech (IDS), the expression of positive affection in the maternal voice and the attentional engagement in dyads of PPD and non-PPD mothers. Participants of this study were 80 mothers and their infants at 3-6 months. According to Edinburgh Postnatal Depression Scale (EPDS) 40 mothers were considered depressed. Mothers and their babies were videotaped during free play interactions. No significant differences were found among groups for the averages of all the categories. Two data sets representing optimal interactions styles were created based on the correlation coefficients. A linear regression analysis indicated that the mother`s years of education was a predictive factor for the occurrence of these interactive styles only for PPD mothers. PPD influenced mother-infant interaction when associated with maternal socio-demographic characteristics.Postpartum depression (PPD) is associated with disturbances in many aspects of mother-infant interaction.  We compared the content of the infant-directed speech (IDS), the expression of positive affection in the maternal voice and the attentional engagement in dyads of PPD and non-PPD mothers. Participants of this study were 80 mothers and their infants at 3-6 months. According to Edinburgh Postnatal Depression Scale (EPDS) 40 mothers were considered depressed. Mothers and their babies were videotaped during free play interactions. No significant differences were found among groups for the averages of all the categories. Two data sets representing optimal interactions styles were created based on the correlation coefficients. A linear regression analysis indicated that the mother`s years of education was a predictive factor for the occurrence of these interactive styles only for PPD mothers. PPD influenced mother-infant interaction when associated with maternal socio-demographic characteristics

Radiation-related superficial oral mucoceles : an under-recognized acute toxicity in head and neck cancer patients

Acute toxicity is usually defined as adverse changes occurring immediately or a short time after the start of oncological treatment. Cross-sectional retrospective study performed with head and neck cancer patients who underwent radiotherapy from 2013 to 2016. Ten (1.2%) patients developed SOMs during radiotherapy, most (80%) of which were men with a mean age of 59.5 years at diagnosis. SOMs mainly affected the floor of the mouth (60%) between the fourth and the sixth weeks of radiation therapy. All lesions were asymptomatic and spontaneously ruptured approximately 9 days after diagnosis. Although rare, SOMs may be regarded as an acute oral toxicity of head and neck radiotherapy

Characteristics of a long-stay institution for the elderly

Objective: To evaluate the operation of a Long-Stay Institution for the Elderly (LSIE), aiming adequacy of the LSIE according to legislation and improving care. Methods: A qualitative, exploratory-descriptive, action research study was performed, in Currais Novos/RN. Routine observation, interviews and records were the used ways for data collection. Results: The institution was philanthropic, approaching type II care modality. The elderly were confined mainly by family abandonment. Health team was incomplete, with workload fewer than recommended by law, and the care team worked without coordination and supervision of a nurse. Conclusion: We hope that intervention proposal will contribute to improvements in the LSIE, improving care quality provided to the elderly

Effectiveness of plant-derived proanthocyanidins on demineralization on enamel and dentin under artificial cariogenic challenge

Dental caries is considered a disease of high prevalence and a constant problem in public health. Proanthocyanidins (PAs) are substances that have been the target of recent studies aiming to control or treat caries. Objective The aim of this in vitro study was to evaluate the efficacy of a treatment with grape seed extract, under cariogenic challenge, to minimize or even prevent the onset of caries in the enamel and dentin. Material and Methods Blocks of enamel and dentin (6.0x6.0 mm) were obtained from bovine central incisors, polished, and selected by analysis of surface microhardness (SH). The blocks were randomly divided into 3 groups (n=15), according to the following treatments: GC (control), GSE (grape seed extract), GF (fluoride – 1,000 ppm). The blocks were subjected to 6 daily pH cycles for 8 days. Within the daily cycling, the specimens were stored in buffered solution. The blocks were then analyzed for perpendicular and surface hardness and polarized light microscopy. Results The means were subjected to statistical analysis using the ANOVA and Fisher's PLSD tests (

The Relevance of Learning Brazilian Sign Language to The Socialization of Deaf People

Through Law nº 10.436 of April 24, 2002, the Brazilian Sign Language (LIBRAS) was made official as a way of communication and expression. From it, the visual-motor language system, with its own grammatical structure, constitutes a language system for transmitting ideas and facts, originating from deaf people communities in Brazil. &nbsp;The Brazilian Law for the Inclusion of Persons with Disabilities (Law nº 13.146 of July 6, 2015) establishes, among others, the provision of bilingual education, with LIBRAS as the first language, and the writing mode of Portuguese as a second language in bilingual schools and classes, as well as in inclusive schools. Within this context, a descriptive exploratory research was conducted at the Center for the Training and Support of Deaf People (CAS), in São Luís/MA. We aimed at investigating the relevance of learning Brazilian Sign Language in the socialization of deaf people, considering the perception of CAS students. Ten deaf students who were currently learning LIBRAS at the Center participated in the study, out of which seven were males and three were females aged between 17 and 36 years old. Data were collected through semi-structured interviews, considering the ethical procedures involving human beings. Results indicated that deaf students learning LIBRAS at CAS do so due to a number of reasons, such as communicating with hearing people, learning, working, having autonomy, being able to leave home, making friends, and spending time with other people. Within this context, the LIBRAS interpreter is of great relevance to the social, educational and professional inclusion of deaf people, as well as a communication mediator between deaf and hearing people. However, the LIBRAS teaching-learning process still requires a more efficient socialization and/or operationalization, aiming to reach society in general, and to include deaf people, thus breaking up myths, stigmas, prejudices, discriminations and unfavorable social actions related to the disability and their human potential. Employing a sensitive look and listening to the exclusion situations many deaf people are suffering is urgently needed to safeguard the respect to the human being and to the deaf people’s culture

Efeito do aldicarbe e do metamidofós na taxa de desenvolvimento de Chrysomya Albiceps, Cochliomyia Macellaria e intervalo Post-mortem.

La presente investigación tuvo como objetivo determinar la relación de la gestión académica y el desempeño docente con la percepción de satisfacción de los estudiantes de medicina de una universidad peruana, 2020. Dicho estudio empleó la metodología de tipo básica, con un método de tipo hipotético – deductivo, con enfoque cuantitativo, de diseño no experimental de nivel correlacional, transaccional. La población estuvo constituida por 250 estudiantes de la facultad de medicina de una universidad peruana y con respecto a la muestra, esta fue obtenida mediante el muestreo no probabilístico seleccionado a conveniencia del investigador y estaba constituida por 125 estudiantes de tercer, cuarto y quinto año de estudios. La técnica empleada para la recolección de datos fue la encuesta, mediante la aplicación de instrumentos estandarizados de escala de Likert para medir el nivel de la gestión académica, el desempeño docente y la percepción de satisfacción de los estudiantes respectivamente. Los resultados encontrados permitieron concluir que existe una relación significativa entre la gestión académica y el desempeño docente con la percepción de satisfacción de los estudiantes de medicina de una universidad peruana, 2020 (Sig.= 0,000 < 0,05) y que además el grado de relación entre la gestión académica con la satisfacción de los estudiantes es buena y positiva con un coeficiente Rho de Spearman = 0,633, y el grado de relación entre el desempeño docente y la satisfacción de los estudiantes es positiva e intensa con un coeficiente Rho de Spearman = 0,817.Tesi