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Renal damage is an important cause of death in patients who have survived the early effects of severe crotalid envenomation. Extracellular matrix of renal tissue is altered by Crotalus toxin activities. The aim of this study was to describe how cytoskeletal proteins and basal membrane components undergo substantial alterations under the action of Crotalus vegrandis crude venom and its hemorrhagic fraction (Uracoina-1) in mice. To detect the proteins in question, the immunoperoxidase method with monoclonal and polyclonal antibodies was used. Cell types within renal lesions were characterized by phenotypic identification, by means of immunohistologic analysis of marker proteins using different primary antibodies against mesangial cells, endothelial cells, cytoskeletal proteins (intermediate filament), extracellular matrix and basal membranes. Samples for morphological study by standard procedures (biotin-streptavidin-peroxidase technique) using light microscopy were processed. Positive and negative controls for each antigen tested in the staining assay were included. After crude venom and hemorrhagic fraction inoculation of mice, the disappearance of cytoskeletal vimentin and desmin and collagen proteins in the kidney was observed. In extracellular matrix and basal membranes, collagen type IV from envenomed animals tends to disappear from 24 h to 120 h after venom injection.

A retrospective study of 9,335 cases of human leptospirosis in the state of São Paulo, Brazil, diagnosed between 1969 and 1997 showed that the disease is endemic throughout the state. Middle-aged adults, with a range of 20-39 years, were most frequently infected (32.40%). The mean annual incidence was 0.53 per 100,000 population and the disease was more frequent in males (87.0%). Cases occurred mainly in January to April each year. A peak was observed in 1991 and 1996 which rainfall average was 159.9 and 160.3, respectively. These data emphasize the potential public health importance of leptospirosis in the state of São Paulo, Brazil.

O objetivo da presente pesquisa foi avaliar os graus de polimorfismos protéicos entre setenta e cinco linhagens de C. albicans isoladas da cavidade oral de crianças saudáveis provenientes de cinco categorias socioeconômicas e oito escolas (particulares e públicas) do município de Piracicaba, Estado de São Paulo, a fim de identificar subespécies de C. albicans e suas similaridades em grupos de populações infantis e estabelecer suas possíveis rotas de disseminação. Culturas celulares foram desenvolvidas em meio YEPD, coletadas por centrifugação e lavadas com solução salina gelada. As proteínas celulares totais foram extraídas por rompimento celular usando pérolas de vidro e submetidas à técnica de SDS-PAGE. Após a eletroforese, as bandas de proteínas foram coradas com Coomassie-blue e analisadas pelo conjunto de programas estatísticos NTSYS-pc versão 1.70. Matriz de similaridade e dendrograma foram gerados, pela aplicação do coeficiente de similaridade de Dice e do algoritmo UPGMA, respectivamente, os quais permitiram avaliar os graus de polimorfismo ou similaridade intra-específico, baseados nos padrões eletroforéticos de proteínas totais de isolados orais de C. albicans. Um total de 13 principais fenons (grupos) foi analisado de acordo com suas características homogêneas (categoria socioeconômica e/ou escola idênticas) e heterogêneas (categorias socioeconômicas e/ou escolas diferentes). Com relação ao aspecto epidemiológico socioeconômico, as composições dos grupos mostraram alta similaridade (0.788 < S D < 1.0) entre algumas linhagens de C. albicans isoladas de crianças saudáveis independentemente de suas camadas socioeconômicas (alta, média e baixa). Isolados de alta similaridade não foram encontrados nas cavidades orais de crianças saudáveis pertencentes às camadas sociais A e D, B e C, ou C e E. Isto pode ser explicado pela ausência de uma rota de disseminação entre estas crianças. Geograficamente, algumas crianças saudáveis entre escolas idênticas e diferentes (particulares e públicas) também são portadoras de linhagens semelhantes, mas tal similaridade não foi encontrada entre outros de determinadas escolas. Esses dados podem refletir uma rota de disseminação restrita destes microrganismos em alguns grupos de escolares saudáveis, a qual pode ser dependente da categoria socioeconômica ou local geográfico de cada criança. Em contraste à alta similaridade, a baixa similaridade ou alto grau de polimorfismo (0.499 < S D < 0.788) dos perfis protéicos foi demonstrado em 23 (30,6%) isolados orais de C. albicans. Considerando o aspecto epidemiológico social, 42,1%, 41,7%, 26,6%, 23,5% e 16,7% foram isolados de crianças provenientes das categorias socioeconômicas A, D, C, B e E, respectivamente, e geograficamente, 63,6%, 50%, 33,3%, 33,3%, 30%, 25% e 14,3% foram isolados de crianças provenientes das escolas LAE, MA, CS, AV, HF, FMC e MEP, respectivamente. Tais resultados sugerem um maior grau de polimorfismo entre algumas linhagens isoladas de crianças saudáveis independentemente de suas camadas sociais ou locais geográficos. Estudos complementares envolvendo escolares saudáveis e seus familiares, professores, serventes, hábitos nutricionais e de higiene deverão ser realizados a fim de estabelecer as fontes de tais padrões de colonização em grupos de populações de crianças saudáveis. Os perfis de proteínas totais obtidos por SDS-PAGE associados com análise numérica computadorizada podem proporcionar critérios adicionais para os estudos epidemiológicos e taxonômicos de C. albicans.

Dermatophytosis are superficial mycoses caused by fungi that can invade stratum corneum and keratinized tissues. In order to study the frequency of dermatophytes species and the clinical manifestations caused by these fungi, in São Paulo, SP, Brazil, the authors analyzed cultures isolated at the Mycology Laboratory from a selected population (15,300 out-patients of the Hospital das Clínicas, Department of Dermatology, Faculty of Medicine of University of São Paulo) from January 1992 to June 2002. The most prevalent dermatophyte was Trichophyton rubrum (48.7%), followed by Microsporum canis (20.9%), Trichophyton tonsurans (13.8%), Trichophyton mentagrophytes (9.7%), Epidermophyton floccosum (4.1%), and Microsporum gypseum (2.5%). These agents determined more than one clinical manifestation, i.e., tinea corporis (31.5%), tinea capitis (27.5%), tinea unguium (14.8%), tinea cruris (13.9%), tinea pedis (9.9%), and tinea manuum (1.9%). Clinical variants of dermatophytosis and their relationship to the etiologic agents were studied and the results were compared to those obtained in previous studies in other regions of Brazil and in other countries.

Strongyloides ratti larval extract was used for the standardization of ELISA to detect genus-specific IgE in human strongyloidiasis. Forty serum samples from monoinfected patients shedding S. stercoralis larvae (Group I), 40 from patients with other intestinal parasites (Group II), and 40 from copronegative healthy subjects (Group III) were analyzed. Genus-specific IgE levels (ELISA Index: EI) were significantly higher in the group I (EI = 1.43) than groups II (EI = 0.70) and III (EI = 0.71), showing positivity rates of 55%, 2.5% and 0%, respectively. Similarly, sera from copropositive patients had significantly higher levels of total IgE (866 IU/mL) as compared to those from group II (302 IU/mL) and III (143 IU/mL). A significant positive correlation was found between levels of Strongyloides specific-IgE and total IgE in sera from patients with strongyloidiasis. In conclusion, S. ratti heterologous extract showed to be a useful tool for detecting genus-specific IgE by ELISA, contributing for a better characterization of the immune response profile in human strongyloidiasis.

A prevalência da infecção pelo Trypanosoma cruzi foi avaliada no município de Berilo, Minas Gerais, Brasil, no período de janeiro a julho de 1997. Uma amostra de 2.261 indivíduos foi estudada sorologicamente mediante o teste de imunofluorescência indireta em sangue coletado em papel de filtro. A taxa de prevalência foi de 18% no total da população estudada e 50% em pessoas da área rural maiores de 30 anos. A percentagem de soropositividade foi 0,17% entre os menores de 10 anos estudados, o que sugere que a transmissão vetorial está controlada na área. Observamos uma diminuição na taxa de soroprevalência entre as pessoas nascidas após 1960 e 1970 o que teria relação com o início das ações de controle. Observou-se também uma redução na taxa de infecção pelo T. cruzi quando comparamos os nossos achados com as estimativas de infecção registradas em um estudo sorológico realizado em Berilo em 1983.

Although several advantages - either constructive or architectural - are assigned to flat slabs, the continuity between consecutive spans in multifloor buildings may turn slab-column connections into a critical region, due to the limited contact between both elements. When transferring moments caused by horizontal and/or vertical eccentric loads are present, these effects are even more pronounced on external panels. Specific studies on the effects of outward eccentricities are still rather scarce, although it is recognized that the codes, in general, are concerned with eventually meeting all potential cases, seeking to improve safety structural performance. Some current recommendations are based on considerable extrapolations, whose theory was originally developed for cases of asymmetric loading at internal connections and need to be consolidated with specific test data. Thus, to investigate the structural behaviour of slabs-edge columns connections, four specimens were tested, reproducing a 2,350 mm x 1,700 mm portion of a 180 mm thick reinforced concrete slab adjacent to a 300 mm x 300 mm cross section squared edge column, with a projection at the base for the imposition of eccentricities. The position of the support under the column has determined the eccentricity, defining in physical terms the interaction between bending moment and shear force, as follows: 300 mm (inward), centred (reference) and 300 mm and 400 mm (outward). Experimental results allowed to comparatively assess the performance of the specimens relating the strain measurements in steel and concrete, vertical displacements, rotations, failure mode and ultimate loads of the slabs. Results indicate that the influence of transferring moments on failure modes is much more pronounced than the shear action in the case of edge connections subjected to outward eccentricities.

The use of prestressed concrete flat slabs in buildings has been increasing in recent years in the Brazilian market. Since the implementation of tall and slender buildings a trend in civil engineering and architecture fields, arises from the use of prestressed slabs a difficulty in ensuring the overall stability of a building without beams. In order to evaluate the efficiency of the main bracing systems used in this type of building, namely pillars in formed "U" in elevator shafts and stairs, and pillars in which the lengths are significantly larger than their widths, was elaborated a computational models of fictional buildings, which were processed and analyzed using the software CAD/TQS. From the variation of parameters such as: geometry of the pillars, thick slabs, characteristic strength of the concrete, reduceofthe coefficient of inertia for consideration of non-linearities of the physical elements, stiffness of the connections between slabs and pillars, among others, to analyze the influence of these variables on the overall stability of the building from the facing of instability parameter Gama Z, under Brazilian standard NBR 6118, in addition to performing the processing of building using the P-Delta iterative calculation method for the same purpose.

Waffle slab structures simulated by computational model are generally analyzed by simplified methods, for both the section geometry (converting into solid slabs or grids) and for the material mechanical properties (linear elastic regime). Results obtained by those studies show large differences when compared with test results, even at low loading levels. This is mainly due to lack of consideration of the eccentricity between the axis of the ribs and the cover, as well as the simplification of the mechanical behavior of concrete tensile strength. The so called more realistic numerical models do consider the effect of the eccentricity between the axis of the cover and ribs. One may also introduce physical nonlinearity of reinforced concrete in these models, obtaining results closer to tests. The objective of this work is to establish a numerical model for the typical section of waffle slabs given the recommendationslisted above. Such model considers the eccentricity between the axis of the ribs and the cover, the physical nonlinearity of concrete in compression and the concrete contribution between cracks (tension stiffening) through a smeared crack model. The finite element program SAP2000 version 16 is used for the non-linear analysis. The area element discretization uses the Shell Layered element along the thickness of layers, allowing for the heterogeneous material behavior of the reinforced concrete. The numerical model was validated comparing results with tests in slabs and, eventually, used to evaluate some waffle slabs subjected to excessive loading.

The main goal of this paper is to show the analysis of the permeability characteristics of three different mixes of pervious concrete produced with the variation of the coarse aggregate size. Two different test methods were used to achieve the hydraulic conductivity of the samples: falling head and constant head permeability tests. Based on test results it is concluded that the pervious concrete mixes have shown to be good drainable materials. Besides, it was found that the permeability of the mixtures does not seem to depend on the size and gradation of the coarse aggregate.

Experimental evidence indicates that both the column rectangularity index and the boundary conditions of the connection may affect the ultimate punching resistance. This paper presents general aspects of these topics and, through the analysis of experimental results of tests on 131 slabs, evaluates the accuracy and suitability of recommendations presented by ABNT NBR 6118, Eurocode 2, ACI 318 and fib Model Code 2010. Experimental results showed that the security level of normative estimates trend to reduce as the column rectangularity increases, and in some cases, the punching resistance was overestimated. Finally, adjustments are suggested in equations presented by NBR 6118 and MC2010 in order to eliminate this trend of unsafe results.

This paper demonstrates the application of the active infrared thermography to detect damage in bonding between concrete and glass fiber reinforced polymer (GFRP). Specimens of concrete and mortar with GFRP externally bonded were prepared and at their interfaces were inserted polystyrene discs to simulate damages. The samples were divided into two groups. In group 1, one sample was correctly bonded by a GFRP plate to the concrete, but in the other three were inserted polystyrene discs which had different diameters to simulate damages in bonding. In group 2, all of the samples contained identical polystyrene discs at their interfaces, but the total thickness of each specimen was different, because the objective was to evaluate the ability of the camera to capture the simulated damage in depth. The experimental procedure was divided into two stages. In the first stage, four types of heating were used to heat samples of group 1: incandescent lamp, kiln, blended lamp and fan heater. Thus, it was possible to detect the damage and to observe its format and length. It was noticed that the infrared images are different depending on the heat source incident on the specimen. Therefore, group 2 was tested only for the more efficient heating (incandescent lamp). In the second stage, the infrared equipment was tested. Some of the parameters that must be inserted in the camera were varied in order to understand their influence on image formation. The results show the effectiveness of infrared thermography to assess adherence in GFRP/concrete interface. In the present work, the best results were obtained when the image is captured towards GFRP/concrete and using incandescent lamp. It was observed that the image and measured temperature suffer significant distortion when a false value was inserted for the parameter emissivity.

Size effect is an important issue in concrete structures bearing in mind that it can influence many aspects of analysis such as strength, brittleness and structural ductility, fracture toughness and fracture energy, among others. Further this, ever more new methods are being developed to evaluate displacement fields in structures. In this paper an experimental evaluation of the size effect is performed applying Digital Image Correlation (DIC) technique to measure displacements on the surface of beams. Three point bending tests were performed on three different size concrete beams with a notch at the midspan. The results allow a better understanding of the size effect and demonstrate the efficiency of Digital Image Correlation to obtain measures of displacements.

This paper presents an experimental investigation on the compressive strength and stress-strain curves of concrete block masonry with varying block and grout strengths and reinforcement ratio. The three-block prisms, built with 8.5 and 15.0 MPa blocks, were tested hollow and filled with 17.0 and 30.0 MPa compressive strength grouts. In addition, prisms and walls with reinforcement rates of 0.15%, 0.40% and 1.0 % were also tested. With the results, it was possible to measure the compressive strength and stress-strain behavior of masonry with inclusion of different grout and reinforcement components, giving parameters for better evaluation of their performance and design. Among the conclusions, it was observed that increasing the compressive strength of masonry is not proportional to the increase of the grouting area and the efficiency of reinforcement to increase compressive strength is low. Stress-strain curves for the several materials combinations are made available.

The safety evaluation of an existing concrete structure differs from the design of new structures. The partial safety factors for actions and resistances adopted in the design phase consider uncertainties and inaccuracies related to the building processes of structures, variability of materials strength and numerical approximations of the calculation and design processes. However, when analyzing a finished structure, a large number of unknown factors during the design stage are already defined and can be measured, which justifies a change in the increasing factors of the actions or reduction factors of resistances. Therefore, it is understood that safety assessment in existing structures is more complex than introducing security when designing a new structure, because it requires inspection, testing, analysis and careful diagnose. Strong knowledge and security concepts in structural engineering are needed, as well as knowledge about the materials of construction employed, in order to identify, control and properly consider the variability of actions and resistances in the structure. With the intention of discussing this topic considered complex and diffuse, this paper presents an introduction to the safety of concrete structures, a synthesis of the recommended procedures by Brazilian standards and another codes, associated with the topic, as well a realistic example of the safety assessment of an existing structure.

Brazilian Codes NBR 6118 and NBR 15575 provide practical values for interstory drift limits applied to conventional modeling in order to prevent negative effects in masonry infill walls caused by excessive lateral deformability, however these codes do not account for infill walls in the structural model. The inclusion of infill walls in the proposed model allows for a quantitative evaluation of structural stresses in these walls and an assessment of cracking in these elements (sliding shear diagonal tension and diagonal compression cracking). This paper presents the results of simulations of single-story one-bay infilled R/C frames. The main objective is to show how to check the serviceability limit states under lateral loads when the infill walls are included in the modeling. The results of numerical simulations allowed for an evaluation of stresses and the probable cracking pattern in infill walls. The results also allowed an identification of some advantages and limitations of the NBR 6118 practical procedure based on interstory drift limits.