999 resultados para carlos Costa


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São raros os momentos, na história das políticas de preservação do patrimônio no Brasil, em que se vê a dimensão de um conflito - gerado pela atribuição de valores a um bem cultural - alcançar repercussão significativa, mobilizando diversos agentes. O caso do edifício Luciano Costa, no Recife, é um exemplo dessa natureza. Neste artigo, procuramos apresentar -a partir da interpretação de uma trama complexa de discursos e ações - a polêmica preservacionista em torno desse edifício, um exemplar arquitetônico singular, por ter simultaneamente duas fachadas, uma eclética e uma modernista. Em grande parte inéditos, os documentos técnico-administrativos da 5ª Superintendência Regional e do Departamento de Documentação do Iphan, assim como aqueles da fundação do Patrimônio Histórico e Artístico de Pernambuco (fundarpe), da Diretoria de Projetos Especiais da Empresa de Urbanização do Recife (URb-Recife) e do Ministério Público de Pernambuco foram as fontes primárias privilegiadas.

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This study investigated the epidemiology of canine ehrlichiosis in Northeastern Brazil, focusing the identification of the Ehrlichia species and vectors involved. Samples were collected from 472 domestic dogs residing in the health districts of Cajazeiras and Itapuã of Salvador city. The average prevalence of antibodies reactive to E. canis by immunofluorescent antibody test (IFAT) (titer > 1:80) was 35.6% (168/472). Blood samples from the E. canis-seropositive animals were tested by nested PCR in order to identify the Ehrlichia species responsible for the infection. Among the seropositives, 58 (34.5%) were found to be PCR-positive for E. canis. Ticks were found in 32 dogs. Nested-PCR analysis showed that 21.9% (7/32) of the Rhipicephalus sanguineus were infected by E. canis. In both dogs and Rhipicephalus sanguineus, nested-PCR for E. ewingii and E. chaffeensis was negative, with no amplification of DNA fragment.

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In lymphocytes (LY), the well-documented antiproliferative effects of IFN-alpha are associated with inhibition of protein synthesis, decreased amino acid incorporation, and cell cycle arrest. However, the effects of this cytokine on the metabolism of glucose and glutamine in these cells have not been well investigated. Thus, mesenteric and spleen LY of male Wistar rats were cultured in the presence or absence of IFN-alpha, and the changes on glucose and glutamine metabolisms were investigated. The reduced proliferation of mesenteric LY was accompanied by a reduction in glucose total consumption (35%), aerobic glucose metabolism (55%), maximal activity of glucose-6-phosphate dehydrogenase (49%), citrate synthase activity (34%), total glutamine consumption (30%), aerobic glutamine consumption (20.3%) and glutaminase activity (56%). In LY isolated from spleen, IFN alpha also reduced the proliferation and impaired metabolism. These data demonstrate that in LY, the antiproliferative effects of IFN alpha are associated with a reduction in glucose and glutamine metabolisms.

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Ti-base alloys containing significant amounts of silicon have been considered for high temperature structural applications. Thus, information concerning phase stability on the Ti-Si system is fundamental and there are not many investigations covering the phase stability of the Ti(3)Si phase, specially its dependence on oxygen/nitrogen contamination. In this work the stability of this phase has been evaluated through heat-treatment of rapidly solidified Ti-rich Ti-Si alloys at 700 A degrees C and 1000 A degrees C. The rapidly solidified splats presented nanometric scale microstructures which facilitated the attainment of equilibrium conditions. The destabilization of Ti(3)Si due to oxygen/nitrogen contamination has been noted.

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The tree Gmelina arborea has been widely introduced in Costa Rica for commercial purposes. This new conditions for melina cause variations on anatomy in secondary xylem of the trees growing in plantations. The objective of the present research was to determine the variation in the anatomy of xylem caused by the ecological conduction variation. Dimensions of fiber, axial parenchyma percentage of cross sections, parameters of vessels and the ray were measured. The results showed that some anatomical characteristics remained stable despite variations of ecological conditions, especially radial parenchyma and anatomical features which were less affected by the altitude. On the other hand, the vessels, axial parenchyma and fiber were less stable because they were affected significantly by the longitude, latitude, altitude and precipitation. Latitude significantly affected vessel percentage, length and diameter of the fiber and lumen. Longitude affected vessel percentage and fiber diameter. Altitude had a significant correlation with the amount of cells at my height. Annual average precipitation affected vessel percentage and diameter, not only of the fiber, but also of the lumen. These results suggest that the new growth conditions of G. arborea trees in Costa Rica have produced an anatomic adaptation.

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The objective of this study was to show the radial variation of some anatomic characteristics, wood density and natural durability of teak (Tectona grandis L.F.) growing in Costa Rica. Samples of trees 13 years old were obtained from two growing sites (high and low growing) of plantations established in a humid tropical climate (CHT) and dry tropical climate (CST). The variables measured of the fibers as well as for the rays were not affected by the climate or the type of growing site, except for the length of the fibers. The fibers of teak wood from the best growing site were significantly larger. Vessels were found with a greater frequency for the CST but mostly solitary in comparison with the CBT. Average density, maximum density and the variation within the ring presented a light higher magnitude for the CST. The quality of the growing site did not affect these variables. The resistance of fungus attack was similar in the area of heartwood near the pith compared to the heartwood near the sapwood for all the conditions evaluated. Nevertheless, it was observed in some trees a similar resistance of fungus attack for areas of sapwood compared to similar areas of heartwood.

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Seven pimarane type-diterpenes re-isolated from Viguiera arenaria Baker and two semi-synthetic pimarane derivatives were evaluated in vitro against the following main microorganisms responsible for dental caries: Streptococcus salivarius, S. sobrinus, S. mutans, S. mitis, S. sanguinis and Lactobacillus casei. The compounds ent-pimara-8(14), 15-dien-19-oic acid (PA); ent-8(14), 15-pimaradien-3 beta-ol; ent-15-pimarene-8 beta, 19-diol; ent-8(14), 15-pimaradien-3 beta-acetoxy and the sodium salt derivative of PA were the most active compounds, displaying MIC values ranging from 2 to 8 mu g.mL(-1). Thus, this class of compounds seems promising as a class of new effective anticariogenic agents. Furthermore, our results also allow us to conclude that minor structural differences among these diterpenes significantly influence their antimicrobial activity, bringing new perspectives to the discovery of new natural compounds that could be employed in the development of oral care products.

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Six pimarane-type diterpenes isolated from Viguiera arenaria Baker and two semi-synthetic derivatives were evaluated in vitro against a panel of representative microorganisms responsible for dental root canal infections. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia, Prevotella buccae, Fusobacterium nucleatum, Bacteroides fragilis, Actinomyces naeslundii, Actinomyces viscosus, Peptostreptococcus micros, Enterococcus faecalis and Aggregatibacter actinomycetemcomitans. The compounds ent-pimara-8(14), 15-dien-19-oic acid, its sodium salt and ent-8(14), 15-pimaradien-3 beta-ol were the most active, displaying MIC values ranging from 1 to 10 mu g mL(-1). The results also allow us to conclude that minor structural differences among these diterpenes significantly influence their antimicrobial activity, bringing new perspectives to the discovery of new chemicals for use as a complement to instrumental endodontic procedures.

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Objective: To study the effect of an 830-nm gallium-aluminum-arsenic (GaAlAs) diode laser at two different energy densities (5 and 15 J/cm(2)) on the epiphyseal cartilage of rats by evaluating bone length and the number of chondrocytes and thickness of each zone of the epiphyseal cartilage. Background Data: Few studies have been conducted on the effects of low-level laser therapy on the epiphyseal cartilage at different irradiation doses. Materials and Methods: A total of 30 male Wistar rats with 23 days of age and weighing 90 g on average were randomly divided into 3 groups: control group (CG, no stimulation), G5 group (energy density, 5 J/cm(2)), and G15 group (energy density, 15 J/cm(2)). Laser treatment sessions were administered every other day for a total of 10 sessions. The animals were killed 24 h after the last treatment session. Histological slides of the epiphyseal cartilage were stained with hematoxylin-eosin (HE), photographed with a Zeiss photomicroscope, and subjected to histometric and histological analyses. Statistical analysis was performed using one-way analysis of variance followed by Tukey's post hoc test. All statistical tests were performed at a significance level of 0.05. Results: Histological analysis and x-ray radiographs revealed an increase in thickness of the epiphyseal cartilage and in the number of chondrocytes in the G5 and G15 groups. Conclusion: The 830-nm GaAlAs diode laser, within the parameters used in this study, induced changes in the thickness of the epiphyseal cartilage and increased the number of chondrocytes, but this was not sufficient to induce changes in bone length.

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Objective: This study aims to investigate the effects of low-level laser therapy (LLLT) on muscle regeneration. For this purpose, the anterior tibialis muscle of 48 male Wistar rats received AlGaInP laser treatment (785 nm) after surgically-induced injury. Background Data: Few studies have been conducted on the effects of LLLT on muscle regeneration at different irradiation doses. Materials and Methods: The animals were randomized into four groups: uninjured rats (UN); uninjured and laser-irradiated rats (ULI); injured rats (IN); and injured and laser-irradiated rats (ILI). The direct contact laser treatment was started 24 h after surgery. An AlGaInP diode laser emitting 75 mW of continuous power at 785 nm was used for irradiation. The laser probe was placed at three treatment points to deliver 0.9 J per point, for a total dose of 2.7 J per treatment session. The animals were euthanized after treatment sessions 1, 2, and 4. Mounted sections were stained with hematoxylin and eosin and used for quantitative morphological analysis, in which the number of leukocytes and fibroblasts were counted over an area of 4480 mu m(2). The data were statistically analyzed by analysis of variance (ANOVA) and the Bonferroni t-test. Results: Quantitative data showed that the number of both polymorphonuclear and mononuclear leukocytes in the inflammatory infiltrate at the injury site was smaller in the ILI(1), ILI(2), and ILI(4) subgroups compared with their respective control subgroups (IN(1), IN(2), and IN(4)) for sessions 1, 2, and 4, respectively (p < 0.05). On the other hand, the number of fibroblasts increased after the fourth treatment session (p < 0.05). With regard to the regeneration of muscle fibers following injury, only after the fourth treatment session was it possible to find muscle precursor cells such as myoblasts and some myotubes in the ILI(4) subgroup. Conclusion: During the acute inflammatory phase, the AlGaInP laser treatment was found to have anti-inflammatory effects, reducing the number of leukocytes at the injury site and accelerating the regeneration of connective tissue.

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The identification of genetic markers associated with chronic kidney disease (CKD) may help to predict its development. Because reduced nitric oxide (NO) bioavailability and endothelial dysfunction are involved in CKD, genetic polymorphisms in the gene encoding the enzyme involved in NO synthesis (endothelial NO synthase [eNos]) may affect the susceptibility to CKD and the development of end-stage renal disease (ESRD). We compared genotype and haplotype distributions of three relevant eNOS polymorphisms (T(-786) C in the promoter region, Glu298Asp in exon 7, and 4b/4a in intron 4) in 110 healthy control subjects and 127 ESRD patients. Genotypes for the T(-786) C and Glu298Asp polymorphisms were determined by TaqMan (R) Allele Discrimination assay and real-time polymerase chain reaction. Genotypes for the intron 4 polymorphism were determined by polymerase chain reaction and fragment separation by electrophoresis. The software program PHASE 2.1 was used to estimate the haplotypes frequencies. We considered significant a probability value of p < 0.05/number of haplotypes (p < 0.05/8 = 0.0063). We found no significant differences between groups with respect to age, ethnicity, and gender. CKD patients had higher blood pressure, total cholesterol, and creatinine levels than healthy control subjects (all p < 0.05). Genotype and allele distributions for the three eNOS polymorphisms were similar in both groups (p > 0.05). We found no significant differences in haplotype distribution between groups (p > 0.05). The lack of significant associations between eNOS polymorphisms and ESRD suggests that eNOS polymorphisms may not be relevant to the genetic component of CKD that leads to ESRD.

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Animal cloning has been associated with developmental abnormalities, with the level of heteroplasmy caused by the procedure being one of its potential limiting factors. The aim of this study was to determine the effect of the fusion of hemicytoplasts or aggregation of hemiembryos, varying the final cytoplasmic volume, on development and cell density of embryos produced by hand-made cloning (HMC), parthenogenesis or by in vitro fertilization (IVF). One or two enucleated hemicytoplasts were paired and fused with one skin somatic cell. Activated clone and zona-free parthenote embryos and hemiembryos were in vitro cultured in the well-of-the-well (WOW) system, being allocated to one of six experimental groups, on a per WOW basis: single clone or parthenote hemiembryos (1 x 50%); aggregation of two (2 x 50%), three (3 x 50%), or four (4 x 50%) clone or parthenote hemiembryos; single clone or parthenote embryos (1 x 100%); or aggregation of two clone or parthenote embryos (2 x 100%). Control zona-intact parthenote or IVF embryos were in vitro cultured in four-well dishes. Results indicated that the increase in the number of aggregated structures within each WOW was followed by a linear increase in cleavage, blastocyst rate, and cell density. The increase in cytoplasmic volume, either by fusion or by aggregation, had a positive effect on embryo development, supporting the establishment of pregnancies and the birth of a viable clone calf after transfer to recipients. However, embryo aggregation did not improve development on a hemicytoplast basis, except for the aggregation of two clone embryos.

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Background: The possibility of using stem cells for regenerative medicine has opened a new field of investigation. The search for sources to obtain multipotent stem cells from discarded tissues or through non-invasive procedures is of great interest. It has been shown that mesenchymal stem cells (MSCs) obtained from umbilical cords, dental pulp and adipose tissue, which are all biological discards, are able to differentiate into muscle, fat, bone and cartilage cell lineages. The aim of this study was to isolate, expand, characterize and assess the differentiation potential of MSCs from human fallopian tubes (hFTs). Methods: Lineages of hFTs were expanded, had their karyotype analyzed, were characterized by flow cytometry and underwent in vitro adipogenic, chondrogenic, osteogenic, and myogenic differentiation. Results: Here we show for the first time that hFTs, which are discarded after some gynecological procedures, are a rich additional source of MSCs, which we designated as human tube MSCs (htMSCs). Conclusion: Human tube MSCs can be easily isolated, expanded in vitro, present a mesenchymal profile and are able to differentiate into muscle, fat, cartilage and bone in vitro.

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Umbilical cord mesenchymal stromal cells (MSC) have been widely investigated for cell-based therapy studies as an alternative source to bone marrow transplantation. Umbilical cord tissue is a rich source of MSCs with potential to derivate at least muscle, cartilage, fat, and bone cells in vitro. The possibility to replace the defective muscle cells using cell therapy is a promising approach for the treatment of progressive muscular dystrophies (PMDs), independently of the specific gene mutation. Therefore, preclinical studies in different models of muscular dystrophies are of utmost importance. The main objective of the present study is to evaluate if umbilical cord MSCs have the potential to reach and differentiate into muscle cells in vivo in two animal models of PMDs. In order to address this question we injected (1) human umbilical cord tissue (hUCT) MSCs into the caudal vein of SJL mice; (2) hUCT and canine umbilical cord vein (cUCV) MSCs intra-arterially in GRMD dogs. Our results here reported support the safety of the procedure and indicate that the injected cells could engraft in the host muscle in both animal models but could not differentiate into muscle cells. These observations may provide important information aiming future therapy for muscular dystrophies.

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We report the microwave dielectric properties and photoluminescence of undoped and europium oxide doped Ta(2)O(5) fibers, grown by laser heated pedestal growth technique. The effects of Eu(2)O(3) doping (1-3 mol %) on the structural, optical, and dielectric properties were investigated. At a frequency of 5 GHz, the undoped material exhibits a dielectric permittivity of 21 and for Eu(2)O(3) doped Ta(2)O(5) samples it increases, reaching up to 36 for the highest doping concentration. Nevertheless, the dielectric losses maintain a very low value. For this wide band gap oxide, Eu(3+) optical activation was achieved and the emission is observed up to room temperature. Thus, the transparency and high permittivity make this material promising for electronic devices and microwave applications. (c) 2008 American Institute of Physics.