CONHECIMENTOS DE UNIVERSITÁRIOS DA ÁREA DA SAÚDE SOBRE CONTRACEPÇÃO E PREVENÇÃO DE DOENÇAS SEXUALMENTE TRANSMISSÍVEIS

Human sexuality is an important component in the individual’s formation. Sexuality has experienced important changes during human history, such as people’s access to information. In this sense we want to investigate the university students’ knowledge in the area of health at the Federal del Ceará University, Colombia regarding behaviors about contraception and STD prevention, since these future professionals will be an important source of information for the population. Data was obtained between May and June 2005 using a questionnaire of 12 objective questions about sexual education, sexual life and knowledge about pregnancy and STD prevention. Regarding information about sex, family, friends and school were the main sources of information. When asked if HIV could be transmitted through oral sex, 87.5% answered correctly, by responding that yes. There is certain knowledge about sexuality among the students. Nevertheless, there is still a lack of preventive knowledge regarding sexual health.La sexualidad humana es un componente importante en la formación del individuo. Sufrió importantes modificaciones a lo largo de la existencia de la vida humana, como la mayor divulgación de informaciones. Buscamos investigar el conocimiento de los universitarios del área de salud de la Universidad Federal del Ceará referente a las conductas de contracepción y prevención de DST, puesto que estas son una importante fuente de información para la población. La colecta de datos tuvo lugar entre mayo y junio de 2005 por medio de un cuestionario objetivo compuesto de 12 preguntas, acerca de la educación sexual, sexualidad y conocimiento en la prevención del embarazo no deseado y de DST. En cuanto a la orientación sexual, la familia, los amigos y la escuela fueron las principales fuentes de información. Preguntados si la transmisión del VIH se produce a través de sexo oral, 87,5% respondió correctamente al afirmar la cuestión como verdadera. Percibimos cierto conocimiento sobre la sexualidad entre los estudiantes, no obstante todavía hay carencias sobre algunos aspectos preventivos de salud sexual.A sexualidade humana é um importante componente na formação do indivíduo. Esta sofreu importantes modificações ao longo da existência da vida humana, como uma maior divulgação de informações. Assim, buscamos investigar o conhecimento de universitários da área da saúde acerca das condutas de contracepção e prevenção de DST, já que estes são importante fonte de informação para a população. A coleta de dados ocorreu entre maio e junho de 2005 por meio de questionário objetivo com 12 questões, abordando dados relacionados à orientação sexual, sexualidade e conhecimento sobre prevenção de DST e gravidez indesejada. Quanto à orientação sexual a família, amigos e a escola foram as principais fontes de informação. Questionados se a transmissão do HIV ocorre através de sexo oral, 87,5% responderam corretamente ao afirmar a questão como verdadeira. Percebemos certo conhecimento sobre a sexualidade entre os universitários, porém ainda há carências sobre alguns aspectos preventivos da saúde sexua

Predicting volume of distribution with decision tree-based regression methods using predicted tissue:plasma partition coefficients

Background: Volume of distribution is an important pharmacokinetic property that indicates the extent of a drug's distribution in the body tissues. This paper addresses the problem of how to estimate the apparent volume of distribution at steady state (Vss) of chemical compounds in the human body using decision tree-based regression methods from the area of data mining (or machine learning). Hence, the pros and cons of several different types of decision tree-based regression methods have been discussed. The regression methods predict Vss using, as predictive features, both the compounds' molecular descriptors and the compounds' tissue:plasma partition coefficients (Kt:p) - often used in physiologically-based pharmacokinetics. Therefore, this work has assessed whether the data mining-based prediction of Vss can be made more accurate by using as input not only the compounds' molecular descriptors but also (a subset of) their predicted Kt:p values. Results: Comparison of the models that used only molecular descriptors, in particular, the Bagging decision tree (mean fold error of 2.33), with those employing predicted Kt:p values in addition to the molecular descriptors, such as the Bagging decision tree using adipose Kt:p (mean fold error of 2.29), indicated that the use of predicted Kt:p values as descriptors may be beneficial for accurate prediction of Vss using decision trees if prior feature selection is applied. Conclusions: Decision tree based models presented in this work have an accuracy that is reasonable and similar to the accuracy of reported Vss inter-species extrapolations in the literature. The estimation of Vss for new compounds in drug discovery will benefit from methods that are able to integrate large and varied sources of data and flexible non-linear data mining methods such as decision trees, which can produce interpretable models. Figure not available: see fulltext. © 2015 Freitas et al.; licensee Springer

Micro-Environmental Mechanical Stress Controls Tumor Spheroid Size and Morphology by Suppressing Proliferation and Inducing Apoptosis in Cancer Cells

Compressive mechanical stress produced during growth in a confining matrix limits the size of tumor spheroids, but little is known about the dynamics of stress accumulation, how the stress affects cancer cell phenotype, or the molecular pathways involved.We co-embedded single cancer cells with fluorescent micro-beads in agarose gels and, using confocal microscopy, recorded the 3D distribution of micro-beads surrounding growing spheroids. The change in micro-bead density was then converted to strain in the gel, from which we estimated the spatial distribution of compressive stress around the spheroids. We found a strong correlation between the peri-spheroid solid stress distribution and spheroid shape, a result of the suppression of cell proliferation and induction of apoptotic cell death in regions of high mechanical stress. By compressing spheroids consisting of cancer cells overexpressing anti-apoptotic genes, we demonstrate that mechanical stress-induced apoptosis occurs via the mitochondrial pathway.Our results provide detailed, quantitative insight into the role of micro-environmental mechanical stress in tumor spheroid growth dynamics, and suggest how tumors grow in confined locations where the level of solid stress becomes high. An important implication is that apoptosis via the mitochondrial pathway, induced by compressive stress, may be involved in tumor dormancy, in which tumor growth is held in check by a balance of apoptosis and proliferation

Modeling the Dynamic Transmission of Dengue Fever: Investigating Disease Persistence

Dengue is the most rapidly spreading mosquito-borne viral disease in the world and approximately 2.5 billion people live in dengue endemic countries. In Brazil it is mainly transmitted by Aedes aegypti mosquitoes. The wide clinical spectrum ranges from asymptomatic infections or mild illness, to the more severe forms of infection such as dengue hemorrhagic fever or dengue shock syndrome. The spread and dramatic increase in the occurrence of dengue cases in tropical and subtropical countries has been blamed on uncontrolled urbanization, population growth and international traveling. Vaccines are under development and the only current disease control strategy is trying to keep the vector quantity at the lowest possible levels. Mathematical models have been developed to help understand the disease's epidemiology. These models aim not only to predict epidemics but also to expand the capacity of phenomena explanation. We developed a spatially explicit model to simulate the dengue transmission in a densely populated area. The model involves the dynamic interactions between humans and mosquitoes and takes into account human mobility as an important factor of disease spread. We investigated the importance of human population size, human renewal rate, household infestation and ratio of vectors per person in the maintenance of sustained viral circulation