24 resultados para hybrid dysgenesis


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Despite advances in our understanding of the mechanisms involved in sex determination and differentiation, the specific roles of many genes in these processes are not completely understood in humans. Both DMRT1 and FGF9 are among this group of genes. Dmrt1 controls germ cell differentiation, proliferation, migration and pluripotency and Sertoli cell proliferation and differentiation. Fgf9 has been considered a critical factor in early testicular development and germ cell survival in mice. We screened for the presence of DMRT1 and FGF9 mutations in 33 patients with 46,XY gonadal dysgenesis. No deletions in either DMRT1 or FGF9 were identified using the MLPA technique. Eight allelic variants of DMRT1 were identified, and in silico analysis suggested that the novel c.968-15insTTCTCTCT variant and the c.774G>C (rs146975077) variant could have potentially deleterious effects on the DMRT1 protein. Nine previously described FGF9 allelic variants and six different alleles of the 3' UTR microsatellite were identified. However, none of these DMRT1 or FGF9 variants was associated with increased 46,XY gonadal dysgenesis. In conclusion, our study suggests that neither DMRT1 nor FGF9 abnormalities are frequently involved in dysgenetic male gonad development in patients with non-syndromic 46,XY disorder of sex development. (C) 2012 Published by Elsevier Masson SAS.

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The generalized finite element method (GFEM) is applied to a nonconventional hybrid-mixed stress formulation (HMSF) for plane analysis. In the HMSF, three approximation fields are involved: stresses and displacements in the domain and displacement fields on the static boundary. The GFEM-HMSF shape functions are then generated by the product of a partition of unity associated to each field and the polynomials enrichment functions. In principle, the enrichment can be conducted independently over each of the HMSF approximation fields. However, stability and convergence features of the resulting numerical method can be affected mainly by spurious modes generated when enrichment is arbitrarily applied to the displacement fields. With the aim to efficiently explore the enrichment possibilities, an extension to GFEM-HMSF of the conventional Zienkiewicz-Patch-Test is proposed as a necessary condition to ensure numerical stability. Finally, once the extended Patch-Test is satisfied, some numerical analyses focusing on the selective enrichment over distorted meshes formed by bilinear quadrilateral finite elements are presented, thus showing the performance of the GFEM-HMSF combination.

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Self-supported organic-inorganic hybrid transparent films have been prepared from bacterial cellulose and boehmite. SEM results indicate that the BC membranes are covered by Boehmite and XRD patterns suggest structural changes on cellulose due to Boehmite addition. Thermal stability is accessed through TG curves and is dependent on Boehmite content. Transparency, as evaluated by UV-Vis absorption, increases with increasing content of boehmite suggesting application of these materials as transparent substrates for opto-electronic devices.

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This communication reports a promising platform for rapid, simple, direct, and ultrasensitive determination of serotonin. The method is related to integration of vertically aligned single-walled carbon nanotubes (SWCNTs) in electrochemical microfluidic devices. The required microfabrication protocol is simple and fast. In addition, the nanomaterial influenced remarkably the obtained limit-of-detection (LOD) values. Our system achieved a LOD of 0.2 nmol L-1 for serotonin, to the best of our knowledge one of the lowest values reported in the literature.

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In this study, we investigated the physiological alterations during ontogeny for cachara (Pseudoplatystoma reticulatum) and their hybrid larvae (Pseudoplatystoma corruscans x P. reticulatum) using lipids and fatty acids as physiological tools to elucidate the basis for differences in these groups' productivity in an industrial setting. Eggs and larvae samples were collected during January and February of 2008 in the city of Bandeirantes, MS, and were divided into three primary phases: phase I (0-16 h after fertilization); phase II (24 h after fertilization to 6 days after fertilization); and phase III (7-25 days after fertilization). The larvae of both groups showed a high degree of similarity, suggesting that the hybrid larvae showed a high level of heritability from the cachara broodstock. Analysis of the total lipid content provided evidence that there is no alteration in lipid concentration during ontogeny for both groups (i.e., the cachara and hybrids). However, the fatty acid profile showed that during the endogenous feeding period (phase II), when the larvae must use the energy reserves from the mother, the cachara larvae used mainly monounsaturated fatty acids for development. This is typical for most fish species, though notably, the hybrids preferentially used saturated fatty acids. Furthermore, certain specific changes demonstrate unique patterns of energy utilization and structural substrates, which may aid in elucidating the empirical differences reported by fish farmers (i.e., that the hybrids perform better than cacharas in captivity).

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Protein and lipid content as well as the fatty acid (FA) composition of storage tissues were analysed in two varieties of Oreochromis niloticus (Red-Stirling and Chitralada) and their hybrid. The animals were maintained in cages for 11 months. The samples were taken when the animals weighed 10, 50, 100, 250 and 500 g. The results showed that changes in the metabolic processes occur during an increase in body mass in both varieties of tilapia and also their hybrid, but that these differences are not found in animals collected at the commercial weight. The protein content of the fillet and liver decreased with growth and the same protein content associated with growth was found for fillet lipid content. The genetic variety did not influence the FA profile of the fillet, but different genotypes had different hepatic FA compositions. Even with the same lipid content, the hepatocytes of Chitralada accumulated higher levels of polyunsaturated fatty acids (PUFA) n6 in triglycerides and increased C22:6n3 in the hepatocyte membranes. The higher n6PUFA content was compensated by a lower fraction of saturated FA in the hepatocyte triglycerides. The skin of Chitralada also had higher n6PUFA and C22:6n3 contents, suggesting a higher ability to deposit PUFA in the skin due to alterations in the liver synthetic pathway.

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The combination of semiconducting oxides and polyaniline in the nanoscale range may result in hybrid materials having enhanced properties, such as electrochromism and charge capacity. This paper reports the spectroscopic, morphological and electrochromic characterization of hybrid films made up of hexaniobate one-dimensional (1D) nanoscrolls and polyaniline prepared by the layer-by-layer assembly technique (LbL). Secondary electron imaging and backscattered electron imaging techniques performed using a scanning electron microscope showed that polyaniline is adsorbed on the hexaniobate nanoscrolls, which confirms the combination of the components in the nanoscale domain. UV-VIS-NIR electronic spectra of the LbL hybrid films showed the absorption tail in the NIR region, assigned to delocalized polarons of the polyaniline. Resonance Raman spectra in the 1000-1700 cm(-1) range indicated that hybrid films present a higher relative intensity of polaron bands at 1337 and 1508 cm(-1) than pristine polyaniline in the emeraldine salt form. These results suggest that hexaniobate nanoscrolls induce a secondary doping of polyaniline. The cyclic voltammetry (CV) data for the hybrid film showed a specific capacity of 870 C cm(-3). According to CV results, the synergistic effect on charge storage properties of the hybrid material is attributed to the enhanced electroactivity of the hexaniobate component in the LbL film. Spectroelectrochemical experiments showed that the electrochromic efficiencies at 420 nm are ca. -41 and 24 cm(2) C-1 as the potential changes from 0.8 to -0.9 V and from -0.9 to -1.8 V, respectively, whereas at 800 nm the efficiencies are ca. -55 and 8 cm(2) C-1 for the same potential ranges. The electrochromic efficiencies and multi-colour character of the LbL film of hexaniobate nanoscrolls and polyaniline indicate that this novel hybrid material is an interesting modified electrode for electrochromic devices.

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We report a technique to palliate hypoplastic left heart syndrome, with no PDA stenting, but with double polytetrafluoroethylene shunt from pulmonary artery to ascending and descending aorta by combined thoracotomies. A 30-day-old female was operated with this technique. Five months after first operation, the child was submitted to Norwood/Glenn operation. Good hemodinamic recovery and initial clinical evolution was observed. The child was extubated in 8th post operatory day and reentubated in the next day due to pulmonary infection. Despite antibiotic treatment, the child died after systemic infectious complications.

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The flower industry represents about one billion dollars in Brazil and the development of techniques aimed at flowering control is required. This study evaluated the influence of gibberellic acid (GA3) on the vegetative and reproductive development of young plants of Phalaenopsis FSNT 'Dai-Itigo' hybrid pink color. The application of GA3 was made by foliar sprays at concentrations of 0, 125, 250, 500 and 1,000 mg L -1. The length of leaves increased significantly when using GA3 at low concentrations, but leaf width decreased. The application of GA3 at 125 mg L -1 showed the best results for the promotion of flowering and flower quality of this orchid hybrid. In this treatment, about 50% of plants treated with GA3 flowered about 6-12 months before the plants that were non-treated with this plant growth regulator. The quality of flowering and flowers was best with 125 mg L -1 GA3.