Cayley: Aplicativo para o aprendizado de matrizes, determinantes e sistemas lineares

This paper presents the proposal for the development of the Cayley app,idealized as a complementary result of an extension project at a federal teachinginstitution in the city of Irati. The application is intended to help the student in thelearning of the matrices, determinants and linear systems, and it is being developed through the use of the App Inventor platform. In addition to contemplating a section with calculators referring to the theme, the application will have a section containing theoretical aspects regarding the theme

Evaluating gene by sex and age interactions on cardiovascular risk factors in Brazilian families

Background: In family studies, it is important to evaluate the impact of genes and environmental factors on traits of interest. In particular, the relative influences of both genes and the environment may vary in different strata of the population of interest, such as young and old individuals, or males and females. Methods: In this paper, extensions of the variance components model are used to evaluate heterogeneity in the genetic and environmental variance components due to the effects of sex and age (the cutoff between young and old was 43 yrs). The data analyzed were from 81 Brazilian families (1,675 individuals) of the Baependi Family Heart Study. Results: The models allowing for heterogeneity of variance components by sex suggest that genetic and environmental variances are not different in males and females for diastolic blood pressure, LDL-cholesterol, and HDL-cholesterol, independent of the covariates included in the models. However, for systolic blood pressure, fasting glucose and triglycerides, the evidence for heterogeneity was dependent on the covariates in the model. For instance, in the presence of sex and age covariates, heterogeneity in the genetic variance component was suggested for fasting glucose. But, for systolic blood pressure, there was no evidence of heterogeneity in any of the two variance components. Except for the LDL-cholesterol, models allowing for heterogeneity by age provide evidence of heterogeneity in genetic variance for triglycerides and systolic and diastolic blood pressure. There was evidence of heterogeneity in environmental variance in fasting glucose and HDL-cholesterol. Conclusions: Our results suggest that heterogeneity in trait variances should not be ignored in the design and analyses of gene-finding studies involving these traits, as it may generate additional information about gene effects, and allow the investigation of more sophisticated models such as the model including sex-specific oligogenic variance components

Heritability of cardiovascular risk factors in a Brazilian population: Baependi Heart Study

<p>Abstract</p> <p>Background</p> <p>The heritability of cardiovascular risk factors is expected to differ between populations because of the different distribution of environmental risk factors, as well as the genetic make-up of different human populations.</p> <p>Methods</p> <p>The purpose of this analysis was to evaluate genetic and environmental influences on cardiovascular risk factor traits, using a variance component approach, by estimating the heritability of these traits in a sample of 1,666 individuals in 81 families ascertained randomly from a highly admixed population of a city in a rural area in Brazil.</p> <p>Results</p> <p>Before adjustment for sex, age, age², and age × sex interaction, polygenic heritability of systolic (SBP) and diastolic (DBP) blood pressure were 15.0% and 16.4%, waist circumference 26.1%, triglycerides 25.7%, fasting glucose 32.8%, HDL-c 31.2%, total cholesterol 28.6%, LDL-c 26.3%, BMI 39.1%. Adjustment for covariates increased polygenic heritability estimates for all traits mainly systolic and diastolic blood pressure (25.9 and 26.2%, respectively), waist circumference (40.1%), and BMI (51.0%).</p> <p>Conclusion</p> <p>Heritability estimates for cardiovascular traits in the Brazilian population are high and not significantly different from other studied worldwide populations. Mapping efforts to identify genetic loci associated with variability of these traits are warranted.</p

Estimating underreporting of leprosy in Brazil using a Bayesian approach.

BACKGROUND: Leprosy remains concentrated among the poorest communities in low-and middle-income countries and it is one of the primary infectious causes of disability. Although there have been increasing advances in leprosy surveillance worldwide, leprosy underreporting is still common and can hinder decision-making regarding the distribution of financial and health resources and thereby limit the effectiveness of interventions. In this study, we estimated the proportion of unreported cases of leprosy in Brazilian microregions. METHODOLOGY/PRINCIPAL FINDINGS: Using data collected between 2007 to 2015 from each of the 557 Brazilian microregions, we applied a Bayesian hierarchical model that used the presence of grade 2 leprosy-related physical disabilities as a direct indicator of delayed diagnosis and a proxy for the effectiveness of local leprosy surveillance program. We also analyzed some relevant factors that influence spatial variability in the observed mean incidence rate in the Brazilian microregions, highlighting the importance of socioeconomic factors and how they affect the levels of underreporting. We corrected leprosy incidence rates for each Brazilian microregion and estimated that, on average, 33,252 (9.6%) new leprosy cases went unreported in the country between 2007 to 2015, with this proportion varying from 8.4% to 14.1% across the Brazilian States. CONCLUSIONS/SIGNIFICANCE: The magnitude and distribution of leprosy underreporting were adequately explained by a model using Grade 2 disability as a marker for the ability of the system to detect new missing cases. The percentage of missed cases was significant, and efforts are warranted to improve leprosy case detection. Our estimates in Brazilian microregions can be used to guide effective interventions, efficient resource allocation, and target actions to mitigate transmission

Heritability of physical activity traits in Brazilian families: the Baependi Heart Study

<p>Abstract</p> <p>Background</p> <p>It is commonly recognized that physical activity has familial aggregation; however, the genetic influences on physical activity phenotypes are not well characterized. This study aimed to (1) estimate the heritability of physical activity traits in Brazilian families; and (2) investigate whether genetic and environmental variance components contribute differently to the expression of these phenotypes in males and females.</p> <p>Methods</p> <p>The sample that constitutes the Baependi Heart Study is comprised of 1,693 individuals in 95 Brazilian families. The phenotypes were self-reported in a questionnaire based on the WHO-MONICA instrument. Variance component approaches, implemented in the SOLAR (Sequential Oligogenic Linkage Analysis Routines) computer package, were applied to estimate the heritability and to evaluate the heterogeneity of variance components by gender on the studied phenotypes.</p> <p>Results</p> <p>The heritability estimates were intermediate (35%) for weekly physical activity among non-sedentary subjects (weekly PA_NS), and low (9-14%) for sedentarism, weekly physical activity (weekly PA), and level of daily physical activity (daily PA). Significant evidence for heterogeneity in variance components by gender was observed for the sedentarism and weekly PA phenotypes. No significant gender differences in genetic or environmental variance components were observed for the weekly PA_NS trait. The daily PA phenotype was predominantly influenced by environmental factors, with larger effects in males than in females.</p> <p>Conclusions</p> <p>Heritability estimates for physical activity phenotypes in this sample of the Brazilian population were significant in both males and females, and varied from low to intermediate magnitude. Significant evidence for heterogeneity in variance components by gender was observed. These data add to the knowledge of the physical activity traits in the Brazilian study population, and are concordant with the notion of significant biological determination in active behavior.</p

Attitudes of nurses towards families: validation of the scale Families' Importance in Nursing Care - Nurses Attitudes

The attitudes of nurses towards families determine the care process. With this study, we aimed to obtain an instrument that would allow us to learn about this variable. Hence, our purpose was to perform the cross-cultural adaptation and evaluate the psychometric features of the Portuguese version of the instrument Families' Importance in Nursing Care - Nurses Attitudes (FINC-NA), which aims to evaluate the attitudes of nurses towards the importance of involving the patient's family in the nursing care. The method recommended by the literature was followed. The sample consisted of 136 nurses working in primary health care. The results obtained in the reliability tests showed good internal consistency (Cronbach's Alpha=0.87). The psychometric study permits us to state that the Portuguese version of the FINC-NA, which in Portuguese is referred to as A importância das famílias nos cuidados de enfermagem - atitudes dos enfermeiros (IFCE-AE), is a reliable and valid tool.As atitudes que os enfermeiros adotam em relação à família condicionam o processo de cuidar. Nosso propósito com este estudo foi nesse sentido: dispor de um instrumento que nos permitisse conhecer esta variável. Assim, nossa proposta foi efetuar a adaptação transcultural e avaliar as propriedades psicométricas da versão portuguesa do instrumento Families' Importance in Nursing Care - Nurses Attitudes (FINC-NA), que visa avaliar as atitudes dos enfermeiros acerca da importância de envolver a família nos cuidados de enfermagem. Foi seguido o método preconizado pela literatura. A amostra foi constituída por 136 enfermeiros dos Cuidados de Saúde Primários. Os resultados obtidos nos testes de confiabilidade revelam uma boa consistência interna para o total dos itens (Alpha de Cronbach = 0,87). O estudo psicométrico permite-nos afirmar que a versão em português da FINC-NA, que denominamos A importância das famílias nos cuidados de enfermagem - atitudes dos enfermeiros (IFCE-AE), é um instrumento fidedigno e válido.Las actitudes adoptadas por enfermeros en relación a la familia condicionan el proceso de cuidar. En tal sentido, nos propusimos con este estudio, disponer de un instrumento que nos permita conocer esta variable. Así, nos propusimos efectuar la adaptación transcultural y evaluar las propiedades psicométricas de la versión portuguesa del instrumento Families Importance in Nursing Care - Nurses Attitudes (FINC-NA), que apunta a evaluar actitudes de enfermeros acerca de involucrar a la familia en los cuidados de enfermería. Se siguió el método sugerido por la literatura. Muestra constituida por 136 Enfermeros de Atención Primaria de Salud. Los resultados obtenidos en pruebas de fiabilidad revelan buena consistencia interna para el total de ítems (Alpha de Cronbach=0,87). El estudio psicométrico nos permite afirmar que la versión en Portugués del FINC-NA, que denominamos La importancia de las familias en el cuidado de enfermería - actitudes de los enfermeros (IFCE-AE) es un instrumento fidedigno y válido

Evaluation of the genotoxic and antigenotoxic potential of Melissa officinalis in mice

Melissa officinalis (L.) (Lamiaceae), a plant known as the lemon balm, is native to the east Mediterranean region and west Asia. Also found in tropical countries, such as Brazil, where it is popularly known as “erva-cidreira” or “melissa”, it is widely used in aqueous- or alcoholic-extract form in the treatment of various disorders. The aim was to investigate in vivo its antigenotoxicity and antimutagenicity, as well as its genotoxic/mutagenic potential through comet and micronucleus assaying. CF-1 male mice were treated with ethanolic (Mo-EE) (250 or 500 mg/kg) or aqueous (Mo-AE) (100 mg/kg) solutions of an M. officinalis extract for 2 weeks, prior to treatment with saline or Methyl methanesulfonate (MMS) doses by intraperitoneal injection. Irrespective of the doses, no genotoxic or mutagenic effects were observed in blood and bone-marrow samples. Although Mo-EE exerted an antigenotoxic effect on the blood cells of mice treated with the alkylating agent (MMS) in all the doses, this was not so with Mo-AE. Micronucleus testing revealed the protector effect of Mo-EE, but only when administered at the highest dose. The implication that an ethanolic extract of M. officinalis has antigenotoxic/antimutagenic properties is an indication of its medicinal relevance

Cohort profile : the Baependi Heart Study-a family-based, highly admixed cohort study in a rural Brazilian town

PURPOSE: Cardiovascular disease (CVD) is a major challenge to global health. The same epidemiological transition scenario is replayed as countries develop, but with variations based on environment, culture and ethnic mixture. The Baependi Heart Study was set up in 2005 to develop a longitudinal family-based cohort study that reflects on some of the genetic and lifestyle-related peculiarities of the Brazilian populations, in order to evaluate genetic and environmental influences on CVD risk factor traits. PARTICIPANTS: Probands were recruited in Baependi, a small rural town in the state of Minas Gerais, Brazil, following by first-degree and then increasingly more distant relatives. The first follow-up wave took place in 2010, and the second in 2016. At baseline, the study evaluated 1691 individuals across 95 families. Cross-sectional data have been collected for 2239 participants. FINDINGS TO DATE: Environmental and lifestyle factors and measures relevant to cardiovascular health have been reported. Having expanded beyond cardiovascular health outcomes, the phenotype datasets now include genetics, biochemistry, anthropometry, mental health, sleep and circadian rhythms. Many of these have yielded heritability estimates, and a shared genetic background of anxiety and depression has recently been published. In spite of universal access to electricity, the population has been found to be strongly shifted towards morningness compared with metropolitan areas. FUTURE PLANS: A new follow-up, marking 10 years of the study, is ongoing in 2016, in which data are collected as in 2010 (with the exception of the neuropsychiatric protocol). In addition to this, a novel questionnaire package collecting information about intelligence, personality and spirituality is being planned. The data set on circadian rhythms and sleep will be amended through additional questionnaires, actimetry, home sleep EEG recording and dim light melatonin onset (DLMO) analysis. Finally, the anthropometric measures will be expanded by adding three-dimensional facial photography, voice recording and anatomical brain MRI

Knowledge, attitude and practice of condom use by women of an impoverished urban area

OBJECTIVE Assessing the adequacy of knowledge, attitude and practice of women regarding male and female condoms as STI/HIV preventive measures. METHOD An evaluative Knowledge, Attitude and Practice (KAP) household survey with a quantitative approach, involving 300 women. Data collection took place between June and August 2013, in an informal urban settlement within the municipality of João Pessoa, Paraiba, Northeast Brazil. RESULTS Regarding the male condom, most women showed inadequate knowledge and practice, and an adequate attitude. Regarding the female condom, knowledge, attitude and practice variables were unsatisfactory. Significant associations between knowledge/religious orientation and attitude/education regarding the male condom were observed. CONCLUSION A multidisciplinary team should be committed to the development of educational practices as care promotion tools in order to improve adherence of condom use