Biofilm formation in catheter-related infections by Panton-Valentine leukocidin-producing Staphylococcus aureus

The use of invasive techniques, such as intravascular catheter insertion, and the formation of biofilms in several devices by methicillin-resistant Staphylococcus aureus (MRSA) have contributed to the increased number of septic patients, morbidity and mortality. This study aimed to evaluate the virulence of strains through catheter colonization and identification of microbial biofilm, as well as pathological changes on the colonized skin. An experimental biofilm formation model utilized catheter fragments implanted subcutaneously in 25 Swiss mice. The technique consisted of inoculating a catheter fragment on the back of each animal, followed by intradermal inoculation of 50 μl of bacterial suspension at 1.0 × 107 colony forming units/ml. After 96 h, catheters were removed for macroscopic analysis and evaluated through culture. Local skin fragments were also extracted for histopathology analysis. Staphylococcus aureus can adhere to catheters, colonize and form biofilms. The high amount of viable bacterial cells colonizing catheters and virulence factors can lead to severe infections of skin and adjacent tissues. [Int Microbiol 19(4): 199-207 (2016)]Keywords: Staphylococcus aureus · biofilms · infections · MRSA · Panton-Valentine leukocidi

Identifying cognitive abilities to improve CS1 outcome

Introductory programming courses entail students’ high failure and dropout rates. In an effort to tackle this problem, we carried out a qualitative study aiming to shed some light on the programming phase that is most challenging for students, in order to elicit the specific difficulties they experience while learning to program. In doing so, distinctive cognitive abilities, differentiating subjects in terms of the way they handle programming tasks, were detected. Such aptitudes are represented in three groups of students: those who learn easily, those who never seem to fully grasp what programming requires despite true effort, and those who experience a sudden insight, making them leap from a point were they had difficulties to another where they overcome them. By interviewing teachers and students, abstraction and sequencing elaboration were found to be the two core skills for programming. These results impelled us to consider the mental models’ approach, concluding that there are very specific cognitive functions that are more favorable to learn programming and that are fostered by more adequate schemas of representing reality. Some conclusions involving Problem-based learning as a fit teaching methodology to overcome students’ difficulties are also presented

Culex quinquefasciatus vitellogenesis: morphological and biochemical aspects

The vitellogenic process in Culex quinquefasciatus, which is triggered by a blood meal, involves the synthesis, distribution and storage of the nutrients necessary for embryo development. The fat body of an adult female Cx. quinquefasciatus revealed two cell types: large trophocytes and small, eosinophilic, "oenocyte-like" cells, which show no morphological changes throughout the gonotrophic cycle. Trophocytes, which only begin to synthesise vitellogenin (Vg) 12 h post-blood meal (PBM), undergo a series of morphological changes following engorgement. These changes include the expansion of the rough endoplasmic reticulum (RER) and Golgi complex, which are later destroyed by autophagosomes. At 84 h PBM, trophocytes return to their pre-engorgement morphology. The ovarian follicles of non-blood-fed Cx. quinquefasciatus contain a cluster of eight undifferentiated cells surrounded by follicular epithelium. After engorgement, the oocyte membrane facing the perioocytic space increases its absorptive surface by microvilli development; large amounts of Vg and lipids are stored between 24 and 48 h PBM. Along with yolk storage in the oocyte, follicular cells exhibit the development of RER cisternae and electron-dense granules begin to fill the perioocytic space, possibly giving rise to endochorion. Later in the gonotrophic cycle, electron-dense vesicles, which are possible exochorion precursors, fuse at the apical membrane of follicular cells. This fusion is followed by follicular cell degeneration.FAPESPCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

Fatores preditores do fenômeno de reinternações de pacientes esquizofrênicos, com transtorno afetivo e psicose não orgânica

OBJECTIVE: The aim of the study was to identify the variables that predict the revolving door phenomenon in psychiatric hospital at the moment of a second admission. METHODS: The sample consisted of 3,093 patients who have been followed during 5 to 24 years after their first hospital admission due to schizophrenia, and affective or psychotic disorders. Those who had had four or more admissions during the study period were considered as revolving door patients. Logistic regression analyses were used to assess the impact of gender, age, marital status, urban conditions, diagnosis, mean period of stay on the first admission, interval between the first and second admissions on the patterns of hospitalization. RESULTS: The variables with the highest predictive power for readmission were the interval between first and second admissions, and the length of stay in the first admission. CONCLUSIONS: These data may help public health planners in providing optimal care to a small group of patients with more effective utilization of the available services.OBJETIVO: Identificar as variáveis preditoras do fenômeno de reinternações (recidividade) em hospital psiquiátrico no momento da segunda internação. MÉTODOS: A amostra consistiu em 3.093 pacientes com diagnósticos de esquizofrenia, transtorno afetivo e psicose não orgânica acompanhados durante um período de, no mínimo, 5 anos e, no máximo, 24 anos. Foram considerados pacientes recidivistas os que tiveram 4 ou mais internações no período do estudo. Foi utilizado o modelo de regressão logística para análise do impacto das variáveis sexo, idade, estado civil, cidade de residência, diagnóstico, tempo de permanência na primeira internação, tempo entre a primeira e a segunda internação, segundo o padrão de re-hospitalização. RESULTADOS: As variáveis com maior poder de predição foram tempo entre a primeira e a segunda internação, tempo de permanência na primeira internação e diagnóstico de esquizofrenia. CONCLUSÕES: Os resultados são importantes para o planejamento de saúde pública, com o intuito de promover melhores cuidados a um grupo de pacientes pequeno, mas com um alto impacto na utilização do serviço

Design procedures for sustainable structural concretes using wastes and industrial by-products

The protection of the environment must be a priority in our society, and the construction sector can contribute significantly to this goal. Construction, being one of the industrial sectors that is more demanding in terms of raw materials, must reinforce its effort to implement, in a more profound and systematic way, the paradigm of the circular economy. In this sense, in recent years several studies have been trying to contribute solutions aimed at reintroducing industrial by-products or residues in new products for the construction industry. It should be noted that nowadays it is increasingly important to introduce a higher percentage of recycled materials in concrete. In this context, the present work addresses the appropriateness of a design procedure proposed to maximize the content of electric arc furnace slag (EAFS) and include recycled tire steel fibers (RTSF) in the production of more sustainable structural concretes. For this, the properties of various concrete mixtures at the fresh and hardened state, obtained by the substantial substitution of coarse and fine natural aggregates by EAFS and fly ash (FA), were investigated. The design of EAFS mixtures was based on two conventional reference mixtures (REF1 and REF2), and by using the modified Andreasen and Andersen particle packing model, these were optimized to achieve maximum packing density. Compressive strength, modulus of elasticity behavior, and fresh and physical properties were assessed in order to define the best mix proportions with respect to the predefined requirements of ordinary mixtures. Untreated recycled tire steel fibers (RTSF) were included in the developed sustainable concrete to perform a comparison of the physical properties with unreinforced concretes developed with natural aggregates (REF2) and with EAFS aggregates (EAFS8D1). This incorporation was intended to improve the physical behavior of unreinforced concretes with EAFS aggregates. Mixtures with high percentages of waste aggregates up to 70% (in weight), and 10% (in weight) of FA were obtained, showing competitive mechanical behavior compared to REF1 and REF2. These concrete compositions showed minimum and maximum compressive strengths between 9 MPa and 37 MPa, respectively. This study coverd the two major classes of concrete used as structural material, namely structural concrete and fiber reinforced concrete.This research was funded by Fundação para a Ciência e a Tecnologia grant number SFRH/BD/135790/2018) and projects with references POCI-01-0247-FEDER-033834, NORTE-01-0145-FEDER-000032.The first author would also like to thank FCT (Fundação para a Ciência e a Tecnologia) for the funding through the PhD grant SFRH/BD/135790/2018. The authors would like to thank DST company, the project RENEw, POCI-01-0247-FEDER-033834, funded by Fundo Europeu de Desenvolvimento Regional (FEDER) and Programa Operacional da Competitividade e Internacionalização do Portugal 2020 (COMPETE 2020), “Next generation monitoring of coastal ecosystems in a scenario of global change”, NORTE-01-0145-FEDER-000032, funded by Fundo Europeu de Desenvolvimento Regional (FEDER) and Programa Operacional Regional do Norte (NORTE2020), and “CirMat: CIRcular aggregates for sustainable road and building MATerials” is funded by Iceland, Liechtenstein and Norway through the EEA Grants and Norway Grants, operationalized by the Portuguese Office of the Secretary of State for the Environment. They are also very grateful to the companies SECIL and SIKA for the material provided that contributed to the realization of this study

Knitted textile KTPs for instrumented underwater building systems

[Excerpt] The main scope of this study was to assess the potential of knitted textiles for underwater instrumented underwater building systems, using textile knitted preforms (multi-shape; multimaterial; etc…), using natural fibres (Hemp, Linen and Cotton)

Fatores associados ao histórico de prática de atividade física em gestantes

It is very important to know about external factors that may influence or cause harmful events during pregnancy, since these may lead to infant morbidity-mortality. On the other hand, it is known that the practice of guided physical activity during pregnancy brings benefits. The aim of this study was to descriptively evaluate the sociodemographic, health and lifestyle characteristics of pregnant women with a history of practicing physical activity. This was an exploratory cross-sectional study on 164 pregnant women divided into two groups: GROUP 1 consisted of women with a history of practicing physical activity, and GROUP 2 consisted of women without such histories. All subjects answered a questionnaire to collect sociodemographic and lifestyle data, in addition to their histories of practicing physical activity. Firstly, the frequencies of the study variables were estimated and then association measurements (prevalence ratios and 95% confidence intervals) between the history of practicing physical activity and the variables in question were obtained. The results showed precariousness of access to primary healthcare services, low income and schooling levels and a lack of regular physical activity practices before and during pregnancy.A necessidade do conhecimento dos fatores externos que podem influenciar na causalidade de eventos deletérios à gestação é de grande relevância, pois podem determinar a morbi-mortalidade infantil. Sabe-se que a prática de atividade física orientada, ao contrário, executada durante a gestação, traz benefícios. O objetivo deste estudo foi avaliar descritivamente os aspectos sociodemográficos, de saúde, estilo de vida em gestantes com histórico de prática de atividade física (PAF). Um estudo exploratório do tipo corte transversal foi composto por 164 grávidas, divididas em dois grupos: o GRUPO 01, de mulheres com histórico de prática de atividade física, e o GRUPO 02, de mulheres sem histórico de prática de atividade física. Todas responderam a um questionário para coletar dados sociodemográficos e de estilo de vida, além de informações acerca do histórico de prática de atividade física. Inicialmente, foram estimadas as freqüências das variáveis estudadas e então obtidas as medidas de associação (RP e IC 95%) entre o histórico de PAF e as variáveis em questão. Os resultados demonstraram uma precariedade no acesso aos serviços básicos de saúde, renda e escolaridade baixas, e a falta de prática de atividade física regular antes e durante a gestação

Factor Analysis and the Social Capital Index: A Study at the Brazil / Bolivia Border

Objective: The study aimed to build the level of social capital by neighborhoods Guajará-Mirim border region between the State of Rondônia, Brazil and the Republic of Bolivia, which in recent years has been showing signs of social fragility due advance not virtuous practices. Method: This work made use of research in secondary bases as well as in primary bases. The tabulation of qualitative and quantitative data was performed in Excel (2010) and for their processing performance index construction purposes were calculated following the factorial analysis techniques presented by Hair et al. [19] Santana [20, 21]; and Choi [22]. For this, we made use of the statistical tool SPSS (Statistical Package for Social Sciences) for the construction of the indices of social capital. The correlation analysis process was done in Excel. results: It was observed that the capital reached regular levels in Guajará-Mirim neighborhoods not observable, so correlations between the studied parameters, however, it needs to be further studied as factors such as the flooding of the Mamore river may have interfered in any way in the implementation process of the field survey to the residents of the city. It became clear that the municipality of Guajará-Mirim suffers from serious social problems and that most problems are correlated with the increase in alcoholic beverage market in the city and use drugs. However, was not observed as the institutional arrangements are dealing with this problem, that is, as public bodies are relating to discuss actions for concrete solutions to this evil that plagues large portion of the population of Guajará-Mirim, mainly young teenagers residents of Guajá-Mamim. However, we hope to continue this work in order to better understand this mechanism of social network between the actors of this process in the region

Local Power as the Basis of the Understanding of the Federative Pact

The research aimed to describe the existing problems in the relationship between City, State and Federal Government, through the Brazilian Federative Pact, mainly for municipalities with population of less than 50,000 inhabitants. The research is structured from a qualitative perspective. The theoretical framework was built from the local power of the discussion based on the understanding of the federal pact and local interest and the municipality in Brazil. The paper argues that the federal pact is little debated, discussed, much less questioned by society in general, it only strengthens the lack of a legal and institutional framework for coordination and cooperation among federal entities in the country, which results in public policy fragmented the territory and without direction, causing waste of public resources