Evaluation of solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry for direct determination of chromium in medicinal plants

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

Long term evaluation of morphometric and ultrastructural changes of testes of alloxan-induced diabetic rats

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

The use of scaning electron microscopy in postvaccinal evaluation of tracheal epithelium of Coturnix coturnix japonica

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

Molecular analysis of the Von Hippel-Lindau (VHL) gene in a family with non-syndromic pheochromocytoma: the importance of genetic testing

Dois pacientes índices da família analisada neste estudo foram submetidos a adrenalectomia bilateral devido a feocromocitoma. Foi, então, realizado o estudo genético dos pacientes e de sete parentes de primeiro grau. Os dois pacientes com feocromocitoma e dois outros membros assintomáticos da família apresentaram a mutação c496G>T no exon 3 do gene VHL. A família perdeu seguimento médico. Três anos após a realização da avaliação genética, a irmã dos pacientes, portadora da mutação, foi encaminhada para o nosso serviço após uma gestação complicada por pré-eclampsia. Ela referia paroxismos sugestivos de feocromocitoma, mas as metanefrinas urinárias eram negativas. Entretanto, a tomografia computadorizada de abdômen evidenciou uma massa adrenal que também se contrastou na cintilografia com metaiodobenzilguanidina (MIBG). Esse estudo mostra que a análise molecular do paciente índice pode levar à identificação de parentes assintomáticos portadores da mutação. Além disso, mesmo com as metanefrinas urinárias negativas, a identificação de uma mutação específica levou a um aumento da suspeita e detecção de feocromocitoma na irmã dos afetados pela doença.

Evaluation of polymethylmethacrylate as ocular implant in rabbits subjected to evisceration

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Non-linear growth models for bullfrog tadpoles

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

Evaluation of rare earth oxides doping SnO2.(Co1/4,Mn3/4)O-based varistor system

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

Nutritional evaluation of elephant-grass silages with byproduct of annato

Objetivou-se avaliar o valor nutritivo de silagens de capim-elefante contendo subproduto do processamento do urucum. Vinte ovinos machos, não-castrados, foram distribuídos em delineamento inteiramente casualizado com cinco dietas (0; 4; 8; 12 e 16% de subproduto de urucum na silagem) e quatro repetições, e utilizados para estimar o consumo, a digestibilidade aparente de nutrientes, o teor de nutrientes digestíveis totais e o balanço de nitrogênio. A adição de subproduto de urucum elevou os consumos de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), extrato etéreo (EE), carboidratos não-fibrosos (CNF), carboidratos totais e nutrientes digestíveis totais (NDT), tanto em relação ao peso vivo (%PV) quanto em relação ao peso metabólico (g kg-1PV0,75). As digestibilidades de MS (55,95%), MO (58,19%), PB (45,34%), FDN (52,79%), FDA (45,79%), EE (34,96%) e CNF (99,86%) não foram influenciadas pela adição de subproduto de urucum. A inclusão de subproduto de urucum na silagem de capim-elefante promoveu aumento na digestibilidade dos carboidratos totais, no teor de NDT e no balanço de nitrogênio. A adição de subproduto de urucum em níveis de até 16% da matéria natural na ensilagem de capim-elefante melhora o consumo de nutrientes e o balanço de nitrogênio.

Comparative efficacy evaluation of moxidectin gel and ivermectin paste against internal parasites of equines in Brazil

A total of 24 male and female equines of mixed breed, 10-20 months of age and naturally infected with internal parasites was utilized in a controlled test to evaluate the efficacy of a moxidectin 2% gel formulation at the dosage of 0.4 mg moxidectin per kg of live weight and an ivermectin 1.87% commercial paste formulation at the dosage 0.2 mg ivermectin per kg applied orally Animals were allocated into three groups of eight horses each based on pre-treatment eggs per gram (EPG) counts and treatments were randomized among the groups. One group was kept as untreated controls. One animal in the moxidectin-treated group died before the end of the trial from a cause unrelated to treatment leaving a total of seven animals in this group. Fecal egg counts were performed three times post-treatment and the number of parasites remaining in each animal was determined. Statistical analyses using geometric means were performed at the 1% level of significance. Both moxidectin and ivermectin preparations reduced initial EPG from a mean of 1600 to 0 on Days 5, 7 and at the end of the trial on Day 14. Efficacy percentages of moxidectin and ivermectin against immature and adult nematodes were as follows: Trichostrongylus axel, Parascaris equorum, Strongylus edentatus, S. vulgaris, Triodontophorus spp. and Gyalocephalus capitatus, 100% for both products; Habronema muscae 99.5 and 99.6%, respectively, Strongyloides westeri, 100 and 99.2%, respectively; Oxyuris equi, 99.6 and 100%, respectively; small strongyles, 99.7% for both products. of the latter, the most numerous were: Cylicocyclus insigne, Cylicostephanus longibursatus and Cyathostomum catinatum. No Gasterophilus nasalis were found in horses from either treated group, while two of eight control horses had infections with this parasite. Moxidectin showed greater efficacy (84.9%) than ivermectin (67.8%) against Strongylus vulgaris larvae found in the mesenteric artery aneurisms, but the difference was not statistically significant. Total parasite counts for both treated groups were significantly lower (p<0.01) than in the non-treated group. No significant differences were noted between moxidectin and ivermectin. Efficacy against the 30 nematode species found in this study was very evident for both products. As expected, neither moxidectin nor ivermectin was effective in controlling the tapeworm Anoplocephala perfoliata. No adverse reactions were observed during the experimental period. (C) 1998 Elsevier B.V. B.V. All rights reserved.

Sealing evaluation of the cervical base in intracoronal bleaching

Discoloration of non-vital teeth is an esthetic deficiency frequently requiring bleaching treatment. The purpose of this study was to evaluate in vitro the cervical base efficacy in order to prevent or to minimize the leakage along the root canal filling and into the dentinal tubules. Thirty-eight extracted single-root human teeth were used, which were biomechanically prepared, filled, and divided into three experimental groups: G1, a cervical base was applied (3 mm of thickness) below the cemento-enamel junction, with resin-modified glass-ionomer cement (Vitremer); G2, the base was done with glass-ionomer cement (Vidrion R); and G3 (Control), did not receive any material as base. A mixture of sodium perborate and hydrogen peroxide 30% was placed inside the pulp chamber for 3 days, and the access opening was sealed with Cimpat. This procedure was repeated thrice. Soon after this, a paste of calcium hydroxide was inserted into the pulp chamber for 14 days. All teeth were covered with two layers of sticky wax, except the access opening, and immersed in blue India Ink for 5 days. The results did not show statistically significant differences between the three groups concerning the leakage inside the dentinal tubules. Regarding the apical direction, a statistical difference (ANOVA P < 0.05) was observed among the experimental group G1 and control group G3. No statistically significant difference was observed between G2 and G3 groups. Therefore, the placement of a cervical base before internal bleaching procedures is still recommended.

Evaluation of Bi as internal standard to minimize matrix effects on the direct determination of Pb in vinegar by graphite furnace atomic absorption spectrometry using Ru permanent modifier with co-injection of Pd/Mg(NO3)(2)

Bismuth was evaluated as an internal standard for the direct determination of Pb in vinegar by graphite furnace atomic absorption spectrometry using Ru as a permanent modifier with co-injection of Pd/Mg(NO3)(2). The correlation coefficient of the graph plotted from the non-nalized absorbance signals of Bi versus Pb was r=0.989. Matrix effects were evaluated by analyzing the slope ratios between the analytical curve, and analytical curves obtained from Pb additions in red and white wine vinegar obtained from reference solutions prepared in 0.2% (v/v) HNO3, samples. The calculated ratios were around 1.04 and 1.02 for analytical curves established applying an internal standard and 1.3 and 1.5 for analvtical curves without. Analytical curves in the 2.5-15 pg L-1 Pb concentration interval were established using the ratio Pb absorbance to Bi absorbance versus analvte concentration, and typical linear correlations of r=0.999 were obtained. The proposed method was applied for direct determination of Pb in 18 commercial vinegar samples and the Pb concentration varied from 2.6 to 31 pg L-1. Results were in agreement at a 95% confidence level (paired t-test) with those obtained for digested samples. Recoveries of Pb added to vinegars varied from 96 to 108% with and from 72 to 86% without an internal standard. Two water standard reference materials diluted in vinegar sample were also analyzed and results were in agreement with certified values at a 95% confidence level. The characteristic mass was 40 pg Pb and the useful lifetime of the tube was around 1600 firings. The limit of detection was 0.3 mu g L-1 and the relative standard deviation was <= 3.8% and <= 8.3% (n = 12) for a sample containing, 10 mu L-1 Pb with and without internal standard, respectively. (C) 2007 Elsevier B.V. All rights reserved.

On non-linear dynamics and a periodic control design applied to the potential of membrane action

The Fitzhugh-Nagumo (fn) mathematical model characterizes the action potential of the membrane. The dynamics of the Fitzhugh-Nagumo model have been extensively studied both with a view to their biological implications and as a test bed for numerical methods, which can be applied to more complex models. This paper deals with the dynamics in the (FH) model. Here, the dynamics are analyzed, qualitatively, through the stability diagrams to the action potential of the membrane. Furthermore, we also analyze quantitatively the problem through the evaluation of Floquet multipliers. Finally, the nonlinear periodic problem is controlled, based on the Chebyshev polynomial expansion, the Picard iterative method and on Lyapunov-Floquet transformation (L-F transformation).

Evaluation of glass ionomer cements properties obtained from niobium silicate glasses prepared by chemical process

Glass ionomer cements (GICs) are glass and polymer composite materials. These materials currently find use in the dental field. The purpose of this work is to obtain systems based on composition 4.5SiO(2)-3Al(2)O(3)-XNb2O5-2CaO to be used in Dentistry. The systems were prepared by chemical route at 700 degrees C. The results obtained by XRD and DTA showed that all systems prepared are glasses. The structures of the obtained glasses were compared to commercial material using Al-27 and Si-29 MAS NMR. The analysis of MAS NMR spectra indicated that the systems developed and commercial material are formed by SiO4 and AlO4 linked tetrahedra. The properties of glass ionomer cements based on the glasses prepared with several niobium contents were studied. Setting and working times of the cement pastes, microhardness and diametral tensile strength were evaluated for the experimental GICs and commercial luting cements. It was concluded that setting time of the cement pastes increased with increasing niobium content of the glasses (X). The properties to the GICs such as setting time and microhardness were influenced by niobium content. (c) 2005 Elsevier B.V. All rights reserved.

Uterine evaluation and gestation diagnosis in owl monkey (Aotus azarai infulatus) using the B mode ultrasound

Background Gynecological and obstetrical ultrasonography has become an indispensable tool in the routine management, health evaluation and research on captive non-human primates.Methods Ultrasound was used to evaluate the uterus and estimate the gestation of owl monkeys. Twelve couples were selected, where five were primiparous and seven multiparous females from the National Primate Center reproductive colony, Ananindeua-PA, Brazil. The procedures were carried out using the GE (R) Logiq 100 MP, equipped with a 7.5 MHz linear probe.Results the females showed a simple uterus, of elongated shape, regular outline and homogeneous echogenic texture. In the uterine measurements craniocaudal diameter, dorsoventral diameter and uterine volume (UV), significant differences were identified (P < 0.05) between ultrasound examinations of primiparous and multiparous females. The UV showed a positive correlation with the number of births. The gestational sac and the embryonic echo were visible between 28 and 38 days after mating. Between 48 and 68 days after mating, embryonic death was identified in all the gestations.Conclusions the chemical (use of tranquilizers) and husbandry factors (capture stress) may be related to the prenatal death. The establishing methods of conditioning the female to the ultrasonographic exam may offer a solution to this problem.

Titanium(IV)-EDTA complex - Kinetics of thermal decomposition by non-isothermal procedures

This work aims the evaluation of the kinetic triplets corresponding to the two successive steps of thermal decomposition of Ti(IV)-ethylenediaminetetraacetate complex. Applying the isoconversional Wall-Flynn-Ozawa method on the DSC curves, average activation energy: E=172.4 +/- 9.7 and 205.3 +/- 12.8 kJ mol(-1), and pre-exponential factor: logA = 16.38 +/- 0.84 and 18.96 +/- 1.21 min(-1) at 95% confidence interval could be obtained, regarding the partial formation of anhydride and subsequent thermal decomposition of uncoordinated carboxylate groups, respectively.From E and logA values, Dollimore and Malek methods could be applied suggesting PT (Prout-Tompkins) and R3 (contracting volume) as the kinetic model to the partial formation of anhydride and thermal decomposition of the carboxylate groups, respectively.