Histopathological changes induced by extracts from the tissue covering the stingers of Potamotrygon falkneri freshwater stingrays

Pain is the most conspicuous symptom observed in patients wounded by stingrays, and skin necrosis is common in accidents by freshwater stingrays. The extract from the stinger integumentary tissue of Potamotrygon falkneri containing toxic components (venom) was tested for its ability to induce histopathological changes in the dorsal skin of mice at different times. 3-6 h after injection, foci of necrosis in isolated basal epidermal cells were observed. Full coagulative necrosis of the skin, subcutaneous tissue and skeletal muscle was evident as soon as 24 h after venom exposure, with a clear demarcation from the normal skin. After 48 h, round collections of necrotic cells start to coalesce originating extensive skin necrotic plaques that detach from viable tissue after 72-96 h. Inflammatory infiltrate was observed after 6 h, but was always mild. Acute vascular thrombosis was rare, and hemorrhage was not present at any time. Superficial bacterial infection was present in two of the examined cases. In conclusion, the venom of P. falkneri is responsible for the development of an early necrosis with mild inflammatory reaction, probably due to direct action of the venom. The severe local damage is probably worsened by the mechanical trauma caused by the stinger. (c) 2010 Elsevier Ltd. All rights reserved.

UNIVERSAL COVERING OF DRIFTLESS CONTROL SYSTEMS

Let M be a finite-dimensional manifold and Sigma be a driftless control system on M of full rank. We prove that for a given initial state x epsilon M, the covering space Gamma(Sigma, x) for a monotonic homotopy of trajectories of Sigma which is recently constructed in [1] coincides with the simply connected universal covering manifold of M and that the terminal projection epsilon(x) : Gamma(Sigma, x) -> M given by epsilon(x) ([alpha]) = alpha(1) is a covering mapping.

Decay of geometry for Fibonacci critical covering maps of the circle

We study the growth of Df `` (f(c)) when f is a Fibonacci critical covering map of the circle with negative Schwarzian derivative, degree d >= 2 and critical point c of order l > 1. As an application we prove that f exhibits exponential decay of geometry if and only if l <= 2, and in this case it has an absolutely continuous invariant probability measure, although not satisfying the so-called Collet-Eckmann condition. (C) 2009 Elsevier Masson SAS. All rights reserved.

Countability and star covering properties

Whenever P is a topological property, we say that a topological space is star P if whenever U is an open cover of X, there is a subspace A subset of X with property P such that X = St(A, U). We study the relationships of star P properties for P is an element of {Lindelof, sigma-compact, countable} with other Lindelof type properties. (C) 2010 Elsevier B.V. All rights reserved.

A quantitative and qualitative evaluation of reports of clinical trials published in six Brazilian dental journals indexed in the Scientific Electronic Library Online (SciELO)

INTRODUCTION: Open access publishing is becoming increasingly popular within the biomedical sciences. SciELO, the Scientific Electronic Library Online, is a digital library covering a selected collection of Brazilian scientific journals many of which provide open access to full-text articles.This library includes a number of dental journals some of which may include reports of clinical trials in English, Portuguese and/or Spanish. Thus, SciELO could play an important role as a source of evidence for dental healthcare interventions especially if it yields a sizeable number of high quality reports. OBJECTIVE: The aim of this study was to identify reports of clinical trials by handsearching of dental journals that are accessible through SciELO, and to assess the overall quality of these reports. MATERIAL AND METHODS: Electronic versions of six Brazilian dental Journals indexed in SciELO were handsearched at www.scielo.br in September 2008. Reports of clinical trials were identified and classified as controlled clinical trials (CCTs - prospective, experimental studies comparing 2 or more healthcare interventions in human beings) or randomized controlled trials (RCTs - a random allocation method is clearly reported), according to Cochrane eligibility criteria. CRITERIA TO ASSESS METHODOLOGICAL QUALITY INCLUDED: method of randomization, concealment of treatment allocation, blinded outcome assessment, handling of withdrawals and losses and whether an intention-to-treat analysis had been carried out. RESULTS: The search retrieved 33 CCTs and 43 RCTs. A majority of the reports provided no description of either the method of randomization (75.3%) or concealment of the allocation sequence (84.2%). Participants and outcome assessors were reported as blinded in only 31.2% of the reports. Withdrawals and losses were only clearly described in 6.5% of the reports and none mentioned an intention-to-treat analysis or any similar procedure. CONCLUSIONS: The results of this study indicate that a substantial number of reports of trials and systematic reviews are available in the dental journals listed in SciELO, and that these could provide valuable evidence for clinical decision making. However, it is clear that the quality of a number of these reports is of some concern and that improvement in the conduct and reporting of these trials could be achieved if authors adhered to internationally accepted guidelines, e.g. the CONSORT statement.

Morphological changes in distant muscle fibers following thermal injury in Wistar rats

PURPOSE: Thermal injury causes catabolic processes as the body attempts to repair the damaged area. This study evaluated the effects of a scald injury on the morphology of muscle fibers belonging to a muscle distant from the lesion. METHODS: Thirty Wistar rats were divided into control (C) and scalded (S) groups. Group S was scalded over 45% of the body surface, standardized by body weight. Rats in both groups were euthanized at four, seven and 14 days following the injury. The middle portions of the medial gastrocnemius muscles were sectioned, stained with hematoxylin and eosin and Picrosirius, and submitted to histological analysis. RESULTS: Control group sections exhibited equidistantly distributed polygonal muscle fibers with peripheral nuclei, characteristic of normal muscle. The injured group sections did not consistently show these characteristics; many fibers in these sections exhibited a rounded contour, variable stain intensities, and greater interfiber distances. A substantially increased amount of connective tissue was also observed on the injured group sections. CONCLUSION: This experimental model found a morphological change in muscle distant from the site of thermal injury covering 45% of the body surface.

Jogo patológico e suas conseqüências para a saúde pública

O artigo teve por objetivo caracterizar o jogo patológico, apresentando as principais conseqüências desse transtorno. Foi realizado levantamento bibliográfico sobre o tema, na literatura nacional e internacional. Foram selecionadas as publicações cujos principais achados enfatizavam prevalência, custos sociais e econômicos associados, legalização de jogos de azar e conseqüente impacto na saúde pública. Alto índice de suicídio, comorbidade com outros transtornos psiquiátricos, problemas familiares e no trabalho, e prática de atos ilícitos foram conseqüências relatadas. A prevalência desse transtorno é maior em países que legalizaram jogos de azar e no Brasil, há evidências do crescimento do número de jogadores patológicos. O desenvolvimento de pesquisas nacionais é imprescindível para a definição de políticas públicas adequadas à realidade brasileira.

A produção do conhecimento sobre o ensino de química nas reuniões anuais da Sociedade Brasileira de Química: uma revisão

This paper discusses the Brazilian academic production on Chemical Education. The main source of information is the annual meeting of the Brazilian Chemical Society (RASBQ) covering the period 1999-2006. All the papers presented by the Division of Chemical Education of the RASBQ were reviewed to permit a discussion about the development of the area in Brazil. This bibliographical revision comprises the following aspects: year of presentation, Brazilian region and institution of production, scholastic level encompassed by the study, the kind of academic work (or research type) and thematic focus of the study.

Estudos sobre iniciação científica no Brasil: uma revisão

O artigo apresenta uma revisão de estudos publicados sobre Iniciação Científica no Brasil, tomando por base levantamento das publicações acadêmicas sobre o tema, que abrangeu o período de 1983 ao primeiro semestre de 2007. Na literatura examinada foram encontrados elementos valiosos para a compreensão do estágio em que se encontram importantes questões pertinentes à Iniciação Científica. A emergência do campo de estudo e suas principais abordagens estão aqui descritas.

Avaliação radiográfica da cobertura acetabular à cabeça femoral, após osteotomia tripla e aplicação de cunha sacroilíaca, em pelve de cadáveres de cães

Na tentativa de evitar algumas das dificuldades associadas à osteotomia pélvica tripla (OPT), foi desenvolvido experimentalmente o método de aplicação de cunha na junção sacroilíaca para aumentar a ventroversão acetabular. O objetivo deste estudo foi aplicar as técnicas de cunha sacroilíaca e OPT em cadáveres e avaliar radiograficamente a eficácia da ventroversão acetabular. Para tal, foram utilizados 10 cadáveres de cães, adultos, com 15-25 kg. Em cada hemipelve direita foi realizada OPT com placas de 20° e 40°. Na hemipelve esquerda foram aplicadas cunhas nas articulações sacroilíacas de 20° e 40°. Avaliações radiográficas em projeções ventrodorsais foram realizadas para mensuração da cobertura acetabular à cabeça femoral nas duas técnicas. De acordo com os dados obtidos pode-se observar que não houve diferença entre a técnica de OPT e o uso de cunha sacroilíaca utilizando implantes de 20° e 40°, mas ocorreu diferença significativa (p<0,05) entre os cães antes e após a aplicação dos implantes de 20° e 40°, e também entre os que receberam implantes de 20° e os de 40°. A aplicação de cunha sacroilíaca produziu resultados semelhantes à OPT, e também se mostrou como de mais fácil aplicação.

Eletrodos modificados por hidróxido de níquel: um estudo de revisão sobre suas propriedades estruturais e eletroquímicas visando suas aplicações em eletrocatálise, eletrocromismo e baterias secundárias

The present review paper describes the main features of nickel hydroxide modified electrodes covering its structural and electrochemical behavior and the newest advances promoted by nanostructured architectures. Important aspects such as synthetic procedures and characterization techniques such as X-Ray diffraction, Raman and Infrared spectroscopy, Electronic Microscopy and many others are detailed herein. The most important aspect concerning nickel hydroxide is related to its great versatility covering different fields in electrochemical-based devices such as batteries, electrocatalytic systems and electrochromic electrodes, the fundamental issues of these devices are also commented. Finally, some of the newest advances achieved in each field by the incorporation of nanomaterials will be shown.

Brazilian offshore wave climate based on NWW3 reanalysis

This paper provides a description of the wave climate off the Brazilian coast based on an eleven-year time series (Jan/1997-Dec/2007) obtained from the NWW3 operational model hindcast reanalysis. Information about wave climate in Brazilian waters is very scarce and mainly based on occasional short-term observations, the present analysis being the first covering such temporal and spatial scales. To define the wave climate, six sectors were defined and analyzed along the Brazilian shelf-break: South (W1), Southeast (W2), Central (W3), East (W4), Northeast (W5) and North (W6). W1, W2 and W3 wave regimes are determined by the South Atlantic High (SAH) and the passage of synoptic cold fronts; W4, W5 and W6 are controlled by the Intertropical Convergence Zone (ITCZ) and its meridional oscillation. The most energetic waves are from the S, generated by the strong winds associated to the passage of cold fronts, which mainly affect the southern region. Wave power presents a decrease in energy levels from south to north, with its annual variation showing that the winter months are the most energetic in W1 to W4, while in W5 and W6 the most energetic conditions occur during the austral summer. The information presented here provides boundary conditions for studies related to coastal processes, fundamental for a better understanding of the Brazilian coastal zone.

Fatores associados à prática de atividade física global e de lazer em idosos: Inquérito de Saúde no Estado de São Paulo (ISA-SP), Brasil

The purpose of this study was to measure the prevalence of global and leisure-time physical activity and associated factors in the elderly. This was a population-based cross-sectional study covering a multiple-stage sample of 1,950 subjects 60 years or older living in areas of São Paulo State, Brazil. Prevalence of global physical activity (assessed through the short version of the International Physical Activity Questionnaire - IPAQ) was 73.9%, and prevalence of leisure-time physical activity was 28.4%. The results highlight the differences between factors associated with global and leisure-time physical activities. The social groups most prone to overall sedentary lifestyle and especially to lack of leisure-time physical activity should be the main targets of health policies aimed at promoting healthier lifestyles.

Vinculação determinística de Bancos de Dados sobre mortalidade por Aids

A vinculação determinística de bancos de dados sobre mortalidade por aids tem apresentado problemas causados por falhas nos arquivos. Assim, os objetivos deste estudo foram: avaliar o desempenho da vinculação determinística em bancos de óbito por aids do Programa de Aprimoramento das Informações de Mortalidade no Município de São Paulo (PRO-AIM) e da Fundação SEADE entre os anos de 2000 e 2004 e estimar a cobertura de cada banco. Utilizou-se a rotina merge de um software para vincular os bancos. A primeira etapa pareou os registros automaticamente e, na segunda etapa, cada banco foi conferido para localizar novos pares. Estimaram-se os óbitos pela soma entre casos pareados e não pareados para calcular a cobertura dos bancos. A primeira etapa da vinculação identificou 91,6% dos pares. A segunda etapa adicionou 457 pares. O total de óbitos foi estimado em 5.855, com cobertura de 97,1% do PRO-AIM e 96% do SEADE. O uso da vinculação determinística cobriu grande parte dos casos. O banco do PRO-AIM proporcionou a maior cobertura, com maior quantidade de informações completas e melhor localização geográfica dos casos.

O tratamento cartográfico da informação em saúde do trabalhador

Apesar do reconhecimento da importância dos conhecimentos geográficos e do uso das ferramentas de análise espacial nos estudos da saúde coletiva, esse é um campo ainda pouco explorado pelos pesquisadores brasileiros. Em levantamento realizado nas principais revistas científicas que veiculam os resultados de pesquisa em saúde do trabalhador, verificou-se o grande predomínio do uso de tabelas e gráficos como meio de organizar e apresentar os resultados obtidos, e o número reduzido de mapas. Para isso foram examinados todos os artigos publicados em quatro periódicos (Revista de Saúde Pública, Cadernos de Saúde Pública, Revista Saúde e Sociedade e Revista Brasileira de Epidemiologia) no período de 1967 a 2009. Uma vez analisado o conjunto de artigos selecionados no estudo, aqueles que utilizaram representações cartográficas receberam atenção especial. Verificou-se que, embora ainda pouco utilizadas, as ferramentas do geoprocessamento e da geoestatística com suporte em SIG abrem um campo de novas possibilidades no uso da cartografia temática em saúde do trabalhador no Brasil. Contudo, recomenda-se para os editores das revistas científicas o detalhamento de normas técnicas para publicação de figuras cartográficas, assim como a elaboração de pareceres específicos que possam auxiliar os autores em vista das modificações necessárias para a melhoria da qualidade da comunicação visual de mapas e da correlação espacial por meio do tratamento cartográfico.