Caracterização de biotérios, legislação e padrões de biossegurança

The use of laboratory animals in conjunction with research on the human organism provides a basis for on understanding of several important physiological and pathological processes. Besides, the results of experimental studies enable technical and safety improvements to be made in surgical techniques used in the medical clinic. As living biological material is involved, we should guarantee its physical well-being, taking into account microbiological contamination and the genetics, nutrition and correct manipulation of the animals, in order to avoid incorrect conclusions from the experiments or unnecessarily large numbers of animals being used. In parallel with the concerns and legislation on the use of laboratory animals, there is also a growing preoccupation with the welfare and safety of those who handle the laboratory animals, since they run the risk of acquiring occupational diseases through contact with zoonotic pathogens or developing allergies. Prevention requires the application of modern technological advances in the design of the animal house and in the work routines. Unfortunately, few establishments in Brazil possess staff with adequate training and a basic infrastructure of research that includes the laboratory animal breeding centers, equivalent to those existing ones in the United States and Europe.

Evaluation of tooth color after bleachingwith and without light-activation

Purpose: The use of different light sources as an adjunct to in-office bleaching has been questioned. Thus, the aim of this study was to evaluate the color changes of teeth after application of bleaching techniques with different products, with and without activation by a LED-laser system. Methods: Twenty-four bovine teeth surfaces were submitted to three bleaching techniques with two commercially available 35% hydrogen peroxide bleaching agents (n=8). The specimens were immersed in red wine for 48 h at 37°C and submitted to the bleaching techniques. Color changes were measured before and after staining as well as immediately after and 24 h after the bleaching treatments, with two different methods of color evaluation, software ScanWhite V1.1 and intra-oral spectrophotometer (Vita Easyshade). Data were analyzed by ANOVA and Kruskal-Wallis test. Results: The statistical analysis showed that there was no statistically significant difference at 5% of significance level between the different groups, independently of the evaluation time, evaluation methods or the use of LED-laser systems. Conclusion: The results suggested that the use of light in the bleaching techniques did not influence the color changes. Copyright: © 2011 Roberto et al.

Modeling of a MIT for the application of a frequency inverter of the electric vehicle

Nowadays, drives that use a combination of induction motors and frequency inverters are very common, a fact due to the financial practicality and viability in purchasing and operating that system. This system modeling and simulation becomes important when it wants to evaluate the performance, to calculate and correct parameters, and it has a fundamental role in functionality and viability analysis for application of new configurations and technologies. This work is about to elaborate a simple induction motor model based in the torque versus speed characteristic, using the linearization method for application in a specific operation range to be controlled by a frequency inverter. © 2011 Springer-Verlag Berlin Heidelberg.

The dimensional regularization in light front

We use dimensional regularization (DR) to evaluate a one-loop four-point function to order g2 in a scalar φ4 model using the light-front coordinates and performing the light-front energy variable integration in the first place. The DR in the light-front is applied to the D - 2 transverse variables. We show the equivalence of the result thus obtained with the standard DR applied to D dimensions. © 2013 American Institute of Physics.

Nasal administration of liquid crystal precursor mucoadhesive vehicle as an alternative antiretroviral therapy

The purpose of this study was to develop a mucoadhesive stimuli-sensitive drug delivery system for nasal administration of zidovudine (AZT). The system was prepared by formulating a low viscosity precursor of a liquid crystal phase, taking advantage of its lyotropic phase behavior. Flow rheology measurements showed that the formulation composed of PPG-5-CETETH-20, oleic acid and water (55, 30, 15% w/w), denominated P, has Newtonian flow behavior. Polarized light microscopy (PLM) revealed that formulation P is isotropic, whereas its 1:1 (w/w) dilution with artificial nasal mucus (ANM) changed the system to an anisotropic lamellar phase (PD). Oscillatory frequency sweep analysis showed that PD has a high storage modulus (G′) at nasal temperatures. Measurement of the mucoadhesive force against excised porcine nasal mucosa or a mucin disk proved that the transition to the lamellar phase tripled the work of mucoadhesion. Ex vivo permeation studies across porcine nasal mucosa exhibited an 18-fold rise in the permeability of AZT from the formulation. The Weibull mathematical model suggested that the AZT is released by Fickian diffusion mechanisms. Hence, the physicochemical characterization, combined with ex vivo studies, revealed that the PPG-5-CETETH-20, oleic acid, and water formulation could form a mucoadhesive matrix in contact with nasal mucus that promoted nasal absorption of the AZT. For an in vivo assessment, the plasma concentrations of AZT in rats were determined by HPLC method following intravenous and intranasal administration of AZT-loaded P formulation (PA) and AZT solution, respectively, at a dose of 8 mg/kg. The intranasal administration of PA resulted in a fast absorption process (Tmax = 6.7 min). Therefore, a liquid crystal precursor formulation administered by the nasal route might represent a promising novel tool for the systemic delivery of AZT and other antiretroviral drugs. In the present study, the uptake of AZT absorption in the nasal mucosa was demonstrated, providing new foundations for clinical trials in patients with AIDS. © 2012 Elsevier B.V. All rights reserved.

Light microscopic evaluation and scanning electron microscopic analysis of horse eyes following deep anterior lamellar keratectomy

Objective To describe the technique of deep anterior lamellar keratoplasty (DALK) with Descemet's membrane (DM) exposure in horse eyes. Also, to compare the efficacy and safety of viscodissection and big-bubble techniques for DALK. Animals studied Thirty-four ex vivo horse eyes. Procedure Deep anterior lamellar keratoplasty was performed in 34 ex vivo horse eyes. Two groups (Group V - viscodissection - 2% sodium hyaluronate; Group A - air - big-bubble) of 17 eyes were studied. Other than the substance used, the surgical technique was similar for both groups. Nonperforated eyes were submitted for light microscopic histologic evaluation and scanning electron microscopic (SEM) analysis. Results Group V - Perforations occurred in 18% of the eyes during surgery. Light microscopy revealed exposure of DM in 28% of the eyes with mean thickness of the remaining stroma being 70.4μm. Group A - Perforations occurred in 42% of the eyes. Light microscopy revealed exposure of DM in 60% of the eyes with mean thickness of the remaining stroma being 23.3μm. No significant differences in safety, efficacy and thickness of the remaining stroma (including all eyes or excluding those with DM exposure) were observed. SEM of the surgical site revealed a more even surface in those eyes with DM exposure compared to eyes with thicker remaining stroma in both groups. Conclusions We describe two DALK techniques (viscodissection and big-bubble) for use in horses. No significant differences in safety, efficacy and thickness of the remaining stroma were observed. However, a nonsignificant trend toward the big-bubble technique being more efficacious but less safe was observed. © 2012 American College of Veterinary Ophthalmologists.

The use of NaOCl in combination with CHX produces cytotoxic product

Objectives: The combination of sodium hypochlorite (NaOCl) and chlorhexidine (CHX) yields a precipitate potentially toxic (PPT). The aim of this study was to evaluate the tissue response to implanted polyethylene tubes filled with PPT-soaked fibrin sponge. Methods: Forty rats received four polyethylene tubes each; each tube was filled with fibrin sponge soaked by 2.5 % NaOCl, 2.0 % CHX, PPT (2.5 % NaOCl plus 2.0 % CHX), or not soaked (control). The observation time points were 7, 15, 30, 60, and 90 days. At each time point, eight animals were killed, and the tubes and surrounding tissues were removed, fixed, and prepared for light microscopic analysis by performing glycol methacrylate embedding, serial cutting into 3-μm sections, and hematoxylin-eosin staining. Qualitative and quantitative evaluations of the reactions were performed. Results were statistically analyzed by Kruskal-Wallis test (p < 0.05). Results: All chemical solutions caused moderate reactions at 7 days. On day 30, PPT group was more cytotoxic than the control group and the CHX group (p < 0.05). On days 15 and 60, PPT group was more cytotoxic than the control group (p < 0.05). On day 90, there was no statistically significant difference between the different groups. Conclusion: PPT is more cytotoxic than NaOCl and CHX alone, particularly in the short term. Clinical significance: Protocols which suggest the use of CHX and NaOCl must be revised because this mixture produces cytotoxic product. © 2013 Springer-Verlag Berlin Heidelberg.

Effects of LED-laser hybrid light on bleaching effectiveness and tooth sensitivity: A randomized clinical study

The study evaluated the effectiveness and the sensitivity of in-office tooth bleaching with the use of a hybrid photo-activation system composed by LEDs and lasers. 40 patients, both genders, aged 18 through 25 years, were randomly distributed into two treatment groups: group I, 35% hydrogen peroxide, with a total bleaching time of 135 min divided into three sessions, and group II, 35% hydrogen peroxide and photo-thermal catalysis by an LED-laser system (300 mW cm-2), for a total bleaching time of 72 min divided into three sessions. The treatment efficiency was measured by reflectance spectroscopy and sensitivity by a visual analog scale (VAS). The final luminosity value (ΔL), color variation (ΔE) and sensitivity (S) resulting from the treatments were analyzed by the generalized estimating equations method (GEEs), and Bonferroni post hoc multiple comparisons at 5% significance. The two groups presented similar colors (ΔE) and luminosities (ΔL) after treatment. Group I presented a greater sensitivity index (37.6 ± 5.9%) compared to group II (11.1 ± 3.3%), statistically significant at p < 0.05. The use of LED-laser hybrid light, as a catalyst of the bleaching agents, showed a significant decrease of provoked tooth sensitivity and a treatment time reduced by 53%, with the same aesthetic results as without a light source. © 2013 Astro Ltd.

Photoelectrochemical properties of FTO/m-BiVO4 electrode in different electrolytes solutions under visible light irradiation

Photoelectrochemical properties of FTO/BiVO4 electrode were investigated in different electrolytic solutions, potassium chloride (KCl) and sodium sulphate (Na2SO4), and under visible light irradiation condition. In order to accomplish that, an FTO/BiVO4 electrode was built by combining the solution combustion synthesis technique with the dip-coating deposition process. The morphology and structure of the BiVO4 electrode were investigated through X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. Photoelectrochemical properties were analyzed through chronoamperometry measurements. Results have shown that the FTO/BiVO4 electrode presents higher electroactivity in the electrolyte Na2SO4, leading to better current stabilization, response time, and photoinduced current density, when compared to KCl electrolyte. Besides, this electrode shows excellent performance for methylene blue degradation under visible light irradiation condition. In Na2SO4, the electrode has shown higher degradation rate, 51 %, in contrast to 44 % in KCl, plus higher rate constant, 174 × 10-4 min-1 compared to 150 × 10-4 min-1 in KCl. Results presented in this communication leads to the indication of BiVO4 thin films as alternate materials to use in heterogeneous photoelectrocatalysis, more specifically in decontamination of surface water. © 2013 Springer-Verlag Berlin Heidelberg.

Efeito de colágeno hidrolisado sobre a qualidade tecnológica de queijo Minas frescal light

Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE

Estudo da estabilidade e da capacidade resistente de painéis estruturais do sistema construtivo Light Steel Framing

Pós-graduação em Engenharia Civil - FEIS

Estudo da atividade ansiolítica e sedativa do óleo essencial das cascas de frutos de espécies do gênero Citrus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Controle de Aedes aegypti: período residual de temefós na água em recipientes de plástico, vidro e borracha, ação larvicida residual em recipientes de borracha e segurança das condições de trabalho na nebulização de malathion

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Os servidores do sistema penitenciário e a luta pela saúde no contexto das instituições prisionais no Pará

A Saúde do trabalhador pode ser entendida como uma condição concreta e dinâmica da qual o trabalhador dispõe para traçar e perseguir seus objetivos em direção ao bem-estar físico, psíquico e social, sendo influenciada pelas condições e organização do trabalho no contexto ao qual está inserido. Este estudo teve como objetivo verificar e analisar o processo de trabalho no sistema Prisional e de que forma podem estar influenciando nos modos de subjetivação dos trabalhadores prisionais do Pará, possibilitando a ocorrência de sofrimento psíquico. Constitui-se em um estudo de caso com abordagem qualitativa que teve como instrumento de pesquisa a observação participante ou direta com entrevistas semi-estruturadas com os servidores prisionais selecionados. A análise do processo de trabalho e as formas que podem influenciar nos modos de subjetivação do servidor prisional para que este se mantenha saudável ou doente, foram baseados na interpretação dos resultados, que foram consubstanciados nos dados coletados na entrevista e na observação participante, na escuta e na interpretação das falas dos trabalhadores do Centro de Recuperação de Castanhal de acordo com a abordagem da Psicodinâmica do Trabalho, por ser uma clínica que busca desenvolver o campo da saúde mental e trabalho. Os principais resultados foram: (I) que o estabelecimento penal apresentou condições de infra-estrutura inadequadas e precárias, necessitando de reformas constantes, falta de equipamentos para desenvolver o trabalho, o número insuficiente de recursos humanos e a convivência com a superlotação prisional, que não difere do restante das prisões brasileiras. (II) o processo de trabalho observado é exaustivo, pelo número insuficiente de recursos humanos, carga horária exaustiva e cobrança para desenvolver um bom trabalho mesmo diante das condições encontradas. (III) servidores penitenciários vulneráveis e expostos ao sofrimento psíquico pela condição do trabalho; pelo tipo de vínculo trabalhista temporário que a grande maioria se encontra; pelo estigma e desvalorização neste tipo de trabalho. Onde estes para manterem-se saudáveis diante das ameaças do meio utilizam-se de estratégias defensivas, como o afastamento subjetivo, em que o servidor deixa de pensar e falar sobre o trabalho. (IV) Diante do exposto sobre a condição e dinâmica do trabalho vejo um otimismo por parte dos servidores, quanto à possibilidade de construir-se um processo de saúde do trabalhador no sistema carcerário brasileiro, acreditando na implementação de políticas públicas viáveis, para o sistema penitenciário, proporcionando ao trabalhador melhores condições de saúde.

Compressive strength of esthetic restorative materials polymerized with quartz-tungsten-halogen light and blue LED

Este estudo comparou a resistência à compressão de uma resina composta e de um compômero, fotoativados com luz halógena convencional de quarto-tungstênio (QTH) (XL 300, 3M/SPE) e LED azul (SmartLite PS; Dentsply/De Trey). Foram confeccionados 40 espécimes em forma de disco usando uma matriz bipartida de politetrafluoretileno (4,0 mm de diâmetro x 8,0 mm de altura) em que o material foi inserido incrementalmente. O tempo de polimerização de cada incremento foi de 40 s para a luz halógena convencional e de 10 s para o LED. Os espécimes foram aleatoriamente alocados em 4 grupos (n=10), de acordo com a fonte de luz e com o material restaurador. Depois de armazenadas em água destilada a 37°C ± 2°C por 24 h, a resistência à compressão dos espécimes foi testada em uma máquina universal de ensaios com célula de carga de 500 kgf a uma velocidade de carregamento de 0,5 mm/min. Os dados (em MPa) foram analisados estatisticamente por ANOVA e teste de Student-Newman-Keuls (p<0,05). Para a resina composta, a fotopolimerização com luz halógena não produziu diferença estatisticamente significante (p>0,05) em sua resistência à compressão quando comparada à fotopolimerização com LED. Contudo, a fotopolimerização do compômero com a luz halógena resultou em uma resistência à compressão significativamente maior que a feita o LED (p>0,05). A resina composta apresentou resistência à compressão significativamente maior que a do compômero, independente da fonte de luz. Concluiu-se que a resistência à compressão dos materiais fotopolimerizados com luz halógena e LED foi influenciada pela densidade de energia empregada e pela composição química dos materiais restauradores estéticos.