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A leishmaniose tegumentar é causada pela picada da fêmea dos insetos flebotomíneos. As lesões podem evoluir de pápulas para úlceras, que apresentam fundo granuloso e bordas infiltradas, as quais são indolores, podendo ser únicas ou múltiplas. Trata-se de uma doença negligenciada e o investimento em seu tratamento é desprezível. Até hoje, são empregados no tratamento medicamentos a base de antimonial pentavalente, além de outros fármacos como pentamidina, anfotericina B, paromomicina, imidazoquinolina, antifúngicos, como o fluconazol (FLU). As microemulsões (MEs) melhorarem a solubilidade e estabilidade dos fármacos, além de proporcionarem ação prolongada, vetorização diferenciada para determinados tecidos ou órgãos do organismo. Este trabalho teve como objetivos desenvolver e caracterizar MEs contendo FLU, caracterizar estruturalmente por meio de análises de microscopia de luz polarizada, análise do tamanho das gotículas, análise do perfil de textura e avaliação da bioadesão. Para o estudo de estabilidade foram empregados ensaios de avaliação visual e determinação do pH. Quanto aos ensaios biológicos in vitro, foram realizados ensaios colorimétricos das amostras visando verificar se o sistema desenvolvido permite a potencialização do poder leishmanicida do FLU contra as formas promastigotas da Leishmania amazonensis. Pelo diagrama de fases observou fases líquido-cristalinas confirmadas pela microscopia de luz polarizada, e foram selecionadas três formulações: uma SLT e duas SVT. Todos os ensaios de caracterização estrutural para a F2 sofreu variação quando acrescentou o fármaco, exceto para o potencial zeta, difração de raios X e bioadesão. Não houve alteração no ensaio estabilidade físico-química no período analisado. Os ensaios biológicos in vitro evidenciaram, nas condições metodológicas, inefetividade do sistema contra as formas promastigotas de L. amazonensis

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Proteínas que apresentam atividades no núcleo e possuem sequência de localização nuclear (NLS) tem seu deslocamento dependente do heterodímero importina-α/β. A importina- (ImpA) é responsável pelo reconhecimento inicial do substrato a ser importado através da interação com os NLS. Os sinais são caracterizados por apresentar um ou mais grupos de aminoácidos básicos, denominados como sequências monopartidas e bipartidas. O fungo Neurospora crassa vem sendo utilizado há mais de 70 anos como organismo modelo em estudos de expressão gênica, desenvolvimento e diferenciação celular, ritmo circadiano, defesa do genoma, bem como outros aspectos da biologia de eucariotos. A presença de um grande número de genes no genoma de N. crassa ainda com funções desconhecidas aponta este organismo como um promissor modelo para o estudo de novos mecanismos genéticos e bioquímicos ainda não identificados. Considerando a importância do metabolismo do glicogênio para os organismos, o presente trabalho teve como objetivo o estudo estrutural de complexos de ImpA com peptídeos NLSs (NCM e NCB) de proteínas envolvidas no metabolismo de glicogênio do fungo N. crassa, utilizando técnicas de cristalografia de proteínas. Monocristais dos complexos ImpA-NCM e ImpA-NCB foram obtidos para a coleta dos dados de difração de raios-X, resultando em dois conjuntos de dados à 2,1Å e 2,45Å de resolução, respectivamente. Após elucidação da estrutura da ImpA, mapas de densidade eletrônica gerados revelaram uma densidade eletrônica no sítio principal de reconhecimento de NLS da ImpA de ambas estruturas, possibilitando modelagem dos peptídeos. Em uma comparação do mapa de densidade eletrônica obtido de ambos complexos com um mapa de uma estrutura nativa de ImpA (70-529) coletada à 2,0Å de resolução, a qual usualmente apresenta um peptídeo “contaminante” no sitio de ligação... (Resumo completo, clicar acesso eletrônico abaixo)

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O rápido crescimento do mercado de dispositivos eletrônicos portáteis, com aplicações em diferentes áreas (telecomunicações, medicina, engenharia), criou uma grande demanda por fontes de potência compactas leves e, sobretudo, de baixo custo. Essa demanda levou ao desenvolvimento de tecnologia de filmes finos nanoestruturados para a obtenção de componentes eletroeletrônicos, por exemplo, memórias de computador. Estes dispositivos são empregados em “notebooks”, circuitos integrados, telefones celulares. O estudo de cristalização de filmes finos ferroelétricos nanoestruturados será feito através da cristalização induzida por rotas convencionais tal como cristalização em forno mufla. A modulação entre os diferentes cátions (Pb, Ca e Ba) para formar o sistema Pb1-x(Ca,Ba)xTiO3 serão analisadas, visando obter filmes com propriedades compatíveis para uso em memórias ferroelétricas. Para isso, os filmes finos serão depositados em substratos adequados controlando-se a homogeneidade química, a microestrutura e a interação filme-substrato

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The increasing demand for devices for solid state applications in many technological areas has resulted in a high demand for new materials. Among these material have the advantage of being manufactured with different chemical compositions, and may have physical properties equal to or higher than the corresponding crystalline material. The aim of this paper was to produce borate glass system 50B2O3 – 15CuO – 20Li2O – 15X (X = Na2O, K2O, RbCl e Cs2O) to analyze the influence of the atomic radius of alkali in the physical properties of this glass system. The glasses were synthesized by the process of melting and molding. The characteristic temperatures were determined by the technique of scanning calorimetry (DSC). The non-crystalline was determined by x-ray diffraction. In order to determine the molar volume a density measurement by using the Archimedes method was used. The structural characterization was carried out using the technique of infrared spectroscopy

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The study of ceramic materials is constantly evolving, especially in research related to advanced ceramics. Once these have many applications, this paper relates to synthesis by solid state reaction of calcium copper titanate (CCTO) ceramic material means doping with strontium. The powders were characterized using thermal analysis techniques such as TG (thermogravimetry), DTA (differencial thermal analysis), dilatometry, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The compositions have submitted weight loss at around 6% with respect to carbonates used, and was attributed a temperature of 950° C to perform the calcination according to thermogravimetric analysis. After the process of calcination and milling, the particles presented approximately spherical shapes and high percentages of substitution Ca2+ with Sr2+ was evident by the presence of necks between to particles due to the milling calcination. Analyses with Energy Dispersive Spectroscopy (EDS) showed stoichiometries in different samples very similar to the theoretical stoichiometry

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The research involving new materials has always been considered as a differential in the development of a technology company. This occurred naturally since ancient times, often motivated by reasons of a certain age, where the most common material used was also the name of your time and may be cited as an example the Bronze Age, and later was the Iron. Currently, the use of firearms are they used in resolving conflicts between countries, or a more equivocal, as an instrument of social banditry make innovations in the area of shielding welcome, whether for personal use, in the form of vests or vehicle such as cars, tanks and even aircraft. In this context, is a Silicon Carbide Ceramic, with low density and high hardness. Thus, the aim of this study is the evaluation and comparison of these materials, seeking to improve their properties by means of additives such as boron and silicon metal and amorphous YAG. For this work, the specimens were pre-shaped by means of uniaxial later to be referred for isostatic pressing and sintering. The maximum percentage for each additive was 5%, except for the YAG whose percentage was 8.2% (mass percentage). All compositions were subjected to the same tests (x-ray diffraction, apparent density, optical microscopy, Vickers hardness, scanning electron Microscopita), so that one could draw a comparison between the materials under study, samples that showed better mechanical properties and micro structural, related here by hardness testing and microscopy (optical and SEM) were the silicon carbide doped with YAG and alumina samples, demonstrating the potential of these materials for ballistic protection. Other compositions have high porosity, which is highly undesirable, since in order to harmful influences on the mechanical properties discussed below

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The objective of the present work was to evaluate surface of experimental alloy Ti-7.5Mo after hydrothermal treatment. Ingots were obtained in arc melting furnace under an argon atmosphere and then homogenized under vacuum at 1100ºC for 86.4 ks to eliminate chemical segregation and after cold worked discs were cutting and grinding. For surface treatment, samples were immersed in a container with NaOH aqueous solution 5M, autoclaved, washed with distilled water. Followed, samples were heat treated and they were soaking in 5xSBF to form an apatite layer on the surface. Surfaces were investigated by, scanning electron microscopy, X-Rays powder diffraction, atomic force microscopy and contact angle, in order to evaluate the wettability of the alloy surface. The results were compared with our previous studies using the group of chemical surface treatments and results shows better condition is 120 minutes in the autoclave

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As they have excellent mechanical properties, corrosion resistance and biocompatibility, much research has been conducted with respect to biomedical applications of titanium alloys. This work aims to study the experimental system binary alloy Ti-15Mo, in the raw state of fusion and heat treatment after homogenization, solubilization and calcination (simulating conditions employed for nanotube growth) targeting biomedical applications. Samples were obtained by casting the components in an electric arc furnace with inert atmosphere of argon. After obtaining the alloy, it was heat treated at three different heat treatments, namely homogenizing, calcining and simulation solubilization. The phases present were analyzed by X-ray diffraction, optical microscopy and microhardness testing

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In this study, a composite of titanium oxide (TixOy) and carbon nanotubes multi-walled (MWCNT) was synthesized on a titanium substrate using the sol-gel method. The electrode obtained (TixOy-MWCNT/Ti) was used to the photodegradation of Carbaryl. The morphology and structure of the TixOy-MWCNT composite were characterized by scanning electron microscopy (SEM), scanning electron microscopy by field emission (FEG-SEM) and X-ray diffraction (XRD). The electrode was evaluated for degradation of Carbaryl (0.9 mmol L-1) in phosphate buffer pH 6, and using chronoamperometry by applying a potential of +1,5 V for 1 h. Using the Ultraviolet-Visible test, the absorbance at 220 nm was collected every 15 min to calculate the percentage of Cabaryl´s degradation. Can be evaluated that the Carbaryl degradation using the TixOy-MWCNT/Ti electrode was 22% more efficient when compared with the electrode without the presence of titanium oxides (MWCNT / Ti)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Agronomia (Ciência do Solo) - FCAV

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The increasing demand for electro-electronic devices, with high performance and multi-functional and the rapid advances of the nanotechnology require the development of new methods and techniques for the production and characterization of nanostructure materials and phenomenological models to describe/to predict some of its properties. The demand for multifunctionality requires, at least, new materials, that can integrate ferroelectric and magnetic properties of high technological interest. Inside of this context, multiferroics material can be considered suitable to integrate two or more physical properties of high technological interest. It can also provides new challenges in the processes of synthesis of new materials, and development of new devices with controlling and simulation of its physical properties and modeling. For this Calcium (Ca)-doped bismuth ferrite (BiFeO3) thin films prepared by using the polymeric precursor method (PPM) were characterized by X-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM), polarization and piezoelectric measurements.In order to study the behavior and determine which are the most important parameters to achieve the optimal property to be applied to a multiferroic materials

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Several alloys present the shape memory effect and among them, the equiatomic NiTi alloy, nitinol, is the most important one. It is usually used in several engineering applications and also in biomedical devices, in the fabrication of orthodontic wire, stents and Judet staples. Although a considerable amount of these biomedical devices is utilized in Brazil and a fraction of it is already made here, all nitinol used is bought abroad. Thus, it is important to develop the necessary know-how to fabricate NiTi wire and sheet. It would mean less importation with job creation and wealth generation for the country. In this work nitinol was obtained powder metallurgy from elemental powders of Ti and Ni using uniaxial compression and uniaxial compression followed by isostatic compression. The final densities achieved were determined by the Archimedes method. The precipitation of intermetallic secondary phases was studied and the samples were characterized by metallographic analysis, optical microscopy and X-ray diffraction. Results indicated that 50 hours sintering route showed a low amount of intermetallics, and no trace of unreacted powder. XRD and metallography at room temperature indicated B19’ as the predominant phase, which corresponds to martensite. Although density results showed little dispersion, the most dense sample was compacted under uniaxial compression and presented 4.8 g/cm3, corresponding to 20.84% porosity. Density variation was considered normal to the measurement process and independent of the compaction mode