203 resultados para arid and semiarid region


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The study of the in-situ cellular immune response is very important for the understanding of different liver infections. In the present study, 53 liver samples obtained by viscerotomy from patients who died during the course of jungle yellow fever were analyzed. The diagnosis was confirmed by serology, viral isolation and virus-specific immunohistochemistry. The specimens were analyzed by immunohistochemistry using specific antibodies for apoptosis, CD45RO, CD4, CD8, CD20, S100, CD57 and CD68. Quantitative analysis of the labeling pattern showed a clear predominance of the different phenotypes in the portal tract and midzone region of the acini. There was a predominance of T CD4+ lymphocytes, accompanied by the presence of T CD8+ lymphocytes, natural killer cells (CD57), macrophages and antigen-presenting cells (S100). The disproportion between the intensity of inflammation and the degree of hepatic injury was probably due to the intense apoptotic component, which classically does not induce an inflammatory response. The present study demonstrates that, despite the disproportion between injury and inflammation, the cellular immune response plays an important role in the pathogenesis of the hepatocytic injury observed in yellow fever, probably as a result of cytolytic actions through mechanisms involving MHC II and the activation of Fas receptors and granzymes/perforins. (C) 2006 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

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The influence of dopants commonly used in SnO2 varistor ceramics, such as CoO, Cr2O3 or Nb2O5, on the structural properties of SnO2 was investigated. Several SnO2-based ceramics containing only one of the dopants were prepared and characterized. Spectroscopic investigations [visible, near infrared (IR) and IR region] were performed to obtain information about dopants valence states inside the ceramics, as well as about their influence on electronic structure of the material. Structural properties were investigated by X-ray diffraction analysis and mechanisms of dopant incorporation were proposed. Obtained results were confirmed with results of the electrical measurements. Microstructural changes in doped ceramics were investigated by scanning electron microscopy (SEM) analysis that showed great differences in densities, grain size, and morphology of the SnO2 ceramics depending on type of dopants and their distribution. (C) 2004 Published by Elsevier B.V.

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To elucidate the morphological differences between placentas from normal and cloned cattle pregnancies reaching term, the umbilical cord, placentomes and interplacentomal region of the fetal membranes were examined macroscopically as well as by light and scanning electron microscopy. In pregnancies established by somatic nucleus transfer (NT), the umbilical cord and fetal membranes were edematous. Placentomal fusion was common, resulting in increased size and a decreased number of placentomes. Extensive areas of the chorioallantoic membrane were devoid of placentomes. An increased number of functional or accessory microcotyledons (< 1 cm) were present at the maternally oriented surface of fetal membranes. Extensive areas of extravasated maternal blood were present within the placentomes and in the interplacentomal region. The crypts on the caruncular surface were dilated and accommodated complexes of more than one primary villus, as opposed to a single villus in non-cloned placentae. Scanning electron microscopy of blood vessel casts revealed that there was also more than one stem artery per villous tree and that the ramification of the vessels failed to form dense complexes of capillary loops and sinusoidal dilations as in normal pregnancies. At the materno-fetal interface, however, the trophoblast and uterine epithelium had normal histology. In conclusion, the NT placentas had a range of pathomorphological changes; this was likely associated with the poor clinical outcome of NT pregnancies. (c) 2007 Elsevier B.V. All rights reserved.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The objectives of this investigation were to understand transplacental transport of iron by secreted uteroferrin (UF) and haemophagous areas of water buffalo placenta and clarify the role(s) of blood extravasation at the placental-maternal interface. Placentomes and interplacentomal region of 51 placentae at various stages of gestation were fixed, processed for light and transmission electron microscopy, histochemistry and immunohistochemistry. Haemophagous areas were present in placentomes collected between 4 and 10 months of pregnancy. Perl's reaction for ferric iron was negative in placentomes, but positive in endometrial glands. Positive staining for UF indicated areas in which it was being taken up by phagocytosis and/or fluid phase pinocytosis in areolae of the interplacentomal mesenchyme, with little staining in endometrial stroma. Imunohistochemistry detected UF in trophectoderm of haemophagous regions of placentomes and in other parts of the foetal villous tree, but the strongest immunostaining was in the epithelial cells and lumen of uterine glands. Ultrastructural analyses indicated that erythrophagocytosis was occurring and that erythrocytes were present inside cells of the chorion that also contained endocytic vesicles and caveolae. Results of this study indicate that both the haemophagous areas of placentomes and the areolae at the interface between chorion and endometrial glands are important sites for iron transfer from mother to foetal-placental tissues in buffalo throughout pregnancy.

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Os caprinos têm um sistema de termorregulação que visa manter a temperatura corporal constante dentro de certos limites, independente da temperatura ambiente. Quando esses limites são estabelecidos, eles são usados em diversos mecanismos fisiológicos para manter a temperatura corporal (TC) dentro dos limites normais. Assim, a produção animal pode diminuir devido ao estresse térmico causado por temperaturas elevadas, especialmente em áreas semi-áridas como o Nordeste do Brasil. Este trabalho teve como objetivo avaliar o comportamento fisiológico de diferentes grupos genéticos de caprinos nativos de acordo com a resposta fisiológica das varáveis temperatura retal (TR), frequência respiratória (FR), batimentos cardíacos (BC) e movimentos ruminais (MR), e estabelecer os parâmetros fisiológicos para estas raças sob as condições do semiárido do Nordeste do Brasil. Foram selecionados aleatoriamente 30 animais, sendo cinco machos e dez fêmeas da raça Canindé e cinco machos e dez fêmeas da raça Moxotó, dos quais foram aferidos as variáveis BC, FR e TR nos meses de abril e setembro/2007 e 2008. Observou-se influência significativa (P<0,05) do período do ano no BC, na FR e na TR na raça Canindé, sendo observados valores mais elevados de BC e TR no período chuvoso. Na raça Moxotó observou-se uma diferença significativa (P<0,05) quanto ao BC e TR entre os períodos estudados, sendo observadas na estação seca maiores valores para estas variáveis. Também se observou nesta raça, uma correlação negativa (47%) entre a temperatura ambiente (TA) e TR no período seco, enquanto que no período chuvoso, essa correlação foi positiva (28%). A correlação entre TA e BC foi negativa (21%) no período chuvoso e, positiva (25%) no período seco. Na raça Canindé observou-se correlação negativa (39%) entre TA e movimento ruminal (MR) na época chuvosa, enquanto que no período seco, essa correlação foi positiva (33%). Os parâmetros clínicos avaliados neste estudo encontram-se dentro da normalidade para a espécie caprina no semi-árido nordestino e a raça Moxotó apresentou comportamento condizente com uma maior tolerância ao clima da região e um maior grau de adaptabilidade.

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An outbreak of botulism was detected in goats in the semiarid region of Brazil. In a flock of 460 goats, 38 does were affected and 37 died. Kids and younger goats were not affected. The main clinical signs were flaccid tetraparesis leading to tetraplegia that was often accompanied by twisted neck, tongue paralysis, and muscle tremors. At the time of the visit, 4 out of 11 affected goats were recumbent. Ambulatory goats had uncoordinated and swaying gaits with hypometria and weakness, mainly of the hind limbs. Two recumbent and four ambulatory goats showed twisted neck. Two recumbent goats were euthanized and necropsied. Non-significant gross and histologic lesions were observed. Samples of the liver, gut and rumen content were collected from the two goats and examined for botulinum toxins using the mouse serum neutralization test. The three samples from one goat were positive for type C toxin. Marked osteophagia was observed when the goats had access to bones in the pasture, and the farmer mentioned that osteophagia was common among goats of the flock. A sample of the plant Hybantus ipecaconha, the most abundant forage available for the goats, contained 2800 mg/kg of Ca and 450 mg/kg of P. One soil sample contained 58.12 mg/kg of Ca and 2.02 mg/kg of P. It was concluded that in this outbreak, botulism was associated with osteophagia probably due to phosphorus deficiency. (C) 2012 Elsevier B.V. All rights reserved.

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A cave bat community from a semiarid region in eastern Brazil was studied during the dry season. A high diversity was observed, with thirteen species recorded. Except for Micronycteris minuta and Lionycteris spurrelli, these bats were also found in other Brazilian karstic areas. The commonest species were the hematophague Desmodus rotundus, the omnivore Carollia perspicillata, and the insectivore Natalus stramineus. The bats formed itinerant colonies, moving frequently inside the cave. L. spurrelli was previously known from Amazonia, usually associated with evergreen forests. The present record extends its range 1600 km to the south. A disjunct distribution explains some morphological differentiation between Amazonia and Olhos d'Agua cave populations. The latter may be a relict of former continuous forest vegetation, which has been fragmented after the climatic optimum. Dispersion through the Cerrado forest gallery is also possible.

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The pressure field of a high-power klystron amplifier in the cathode and anode region was investigated. The investigation was performed using a 1.3 GHz, 100 A and 240 kV high-power klystron with five reentrant coaxial cavities, assembled in cylindrical drift tube 1.2 m long. The diffusion equation in mathematical model was also solved by using a 3-D finite element method code, in order to obtain pressure profile in region of interest. The results show that density profile of molecules between cathode-anode region was determined, where cathode pressure is approximately 10% higher than anode pressure.

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This study aimed at evaluating the antisepsis of the root canal system (RCS) and periapical region (PR) provided by rotary instrumentation associated with chlorhexidine + calcium hydroxide as intracanal medicament. Chronic periapical lesions were induced in 26 pre-molar roots in two dogs. After microbiological sampling, automatic instrumentation using the Profile system and irrigation with 5.25% sodium hypochlorite solution, with a final rinse of 14.3% EDTA followed by profuse irrigation with physiological saline were carried out in 18 root canals. After drying the canals, a paste based on calcium hydroxide associated with a 2% chlorhexidine digluconate solution was placed inside them. After 21 days, the medication was removed, leaving the root canals empty and coronally sealed. After 96 hours, a final microbiological sample was obtained, followed by histomicrobiological processing by the Brown & Brenn method. Eight untreated root canals represented the control group (C-G). Based on the Mann-Whitney test at a confidence level of 5% (p < 0.05), the procedures of antisepsis used offered significant efficacy (p < 0.05) resulting in 100.0% of the canals free of microorganisms. In the C-G, an elevated incidence of various microbial morphotypes was confirmed in all sites of the RCS, with the presence of microbial colonies in the periapical region. In contrast, the experimental group showed a similar pattern of infection in the RCS, although less intense and a reduced level of periapical infection (p < 0.05). It was concluded that adequate instrumentation followed by the application of calcium hydroxide + chlorhexidine offered significant elimination of microorganisms.

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The experiment was developed based on the importance of the nutritional factor cunhã for large and small, animals and on the growth of this forage in typical soils of the semiarid region, generally with salinity from natural or anthropogenic action. The experiment was performed in vessels with a capacity of 5kg prepared in a protected environment with full sunshine in the Department of Technology and Social Sciences (DTCS) of UNEB Campus III in Juazeiro - BA. It evaluated the effect of seven different salt concentrations on increasing levels of irrigation water electrical conductivity - ECw (0, 2, 4, 6, 8, 10 and 12 dS/m), at room temperature. The analysis of culture were taken every seven days observing the number of leaves, stem diameter, plant, plant length and total chlorophyll content at 13; 20; 27; 34 and 40 days after the start of irrigation with saline. The contents of proline, the ratio aero part/Root (AP/Rt), the root length and water content were evaluated in the 40 th day after the onset of treatment. The results showed that the elevation of ECw affected all variables.

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Different procedures for the integrated method of diagnosis and recommendation may influence the accuracy of foliar diagnosis of mango. Thus, the objective of this study was to compare the diagnosis of nutritional status of mango obtained by different methods of assessing nutritional status, comparing multivariate relations (method CND) with bivariate relationships (DRIS) i.e., variations in the use of specific or preliminary standards and a logarithmic transformation of the data. The macro and micronutrient leaf analysis results of 63 mango orchards of Lower-middle São Francisco River Valley, Brazil, were used. To interpret nutritional status the Potential Response to Fertilization (PRA) criteria was used. The CND and DRIS methods, with and without logarithmic transformation and using specific or preliminary standards, which showed similar performance in assessing the nutritional status of the mango in Lower-middle San Francisco. Mango orchards in the semiarid region of northeast Brazil, the micronutrient deficiencies (Zn, Fe and Cu) were more frequent than macronutrient deficiency.

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The wrist and hand region has been the most commonly used for estimating age and osseous development due to the great number of ossification centers. The aim was to determine which method, Tanner & Whitehouse's (TW3), Greulich & Pyle's (GP) or Eklof & Ringertz's, more closely relates to the chronological age in subjects with Down syndrome with chronological ages between 61 and 180 months, using wrist and hand radiographs. The sample consisted of 85 radiographs, 52 of males and 33 of females. Eklof & Ringertz's method was computerized (Radiomemory). Greulich & Pyle's atlas was used and compared with the wrist and hand radiographs. For the TW3 method, 13 ossification centers were evaluated; for each one of them, there are seven or eight development stages to which scores are assigned; these scores are then added and the results are transformed into osseous age values. No statistically significant differences were observed between the male and female genders for methods TW3 and GP, contrasting with the observed differences for the Eklof & Ringertz method. Correlation (r2) between osseous and chronological ages was 0.8262 for TW3 and 0.7965 for GP, while for the method of Eklof & Ringertz, it was 0.7656 for females and 0.8353 for males. The author concluded that the osseous age assessment method that better related to the chronological age was the TW3, followed by Greulich & Pyle's and Eklof & Ringertz's.