985 resultados para Rapid slide agglutination test


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The purpose of this study was to evaluate bioequivalence of two commercial 8 mg tablet formulations of ondansetrona available ill the Brazilian market. In this study, a simple, rapid, sensitive and selective liquid chromarography-tandem mass spectrometry method is described for the determination of ondansetron in human plasma samples. The method was validated over a concentration range of 2.5-60 ng/ml and used in a bioequivalence trial between orally disintegrating and conventional tablet ondansetron formulations, to assess its usefulness in this kind of Study. Vonau flash (R) (Biolab Sanus Farmaceutica, Brazil, as test formulations) and Zofran (R) (GlaxoSmithKline, Brazil, as reference formulation) were evaluated following a single 8 mg close to 23 healthy volunteers of both genders. The dose was administered after an overnight fast according to a two-way crossover design. Bioequivalence between the products was determinated by Calculating 90% confidence interval (90% CI) for the ratio of C(max), AUC(0-t) and AUC(0-(sic)) values for the test and reference products, using logarithmically transformed data. The 90% confidence interval for the ratio of C(max) (87.5-103.8%), AUC(0-t) (89.3-107.2%) and AUC(0--(sic)) (89.7-106.0%) values for the test and reference products is Within the 80-125% interval, proposed by FDA, EMEA and ANVISA. It was concluded that two ondansetron formulations are bioequivalent ill their rate and extent of absorption. (C) 2008 Elsevier B.V. All rights reserved.

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New rapid first-derivative spectrophotometric (UVDS) and a stability-indicating high performance liquid chromatographic (HPLC) methods were developed, validated and successfully applied in the analysis of loratadine (LT) in tablets and syrups. In the UVDS method, 0.1 M HCl was used as solvent. The measurements were made at 312.4 nm in the first order derivative spectra. The HPLC method was carried out on a RP-18 column with a mobile phase composed of methanol-water-tetrahydrofuran (50:30:20, v/v/v). UV detection was made at 247 nm. For HPLC methods the total analysis time was <3min, adequate for routine quality control of tablets and syrups containing loratadine.

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This paper describes an analytical method for the rapid screening and identification of the phenolic constituents present in the polar extracts of different Lychnophora spp. using LC-UV/DAD-ESI-MS and LC-UV/DAD-ESI-MS/MS. Compounds were identified based on UV, retention time, MS experiments and MS/MS of precursor ion or standard. On-line phytochemical investigation of Lychnophora spp. allowed for the identification of flavonoids, chlorogenic acid derivatives and lactones. Some of the observed compounds were for the first time identified in Lychnophora species in a fast analytical procedure. The data obtained here may be helpful to the investigation of polar constituents from other Lychnophora species.

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The aim of this work was to evaluate possible cytotoxic effects of topical creams and lotions produced with Buriti oil and commercial surfactants on human keratinocytes HaCat and 3T3 embryonic mouse fibroblast cultures. We also aimed to assess the cytotoxicity of the surfactants used to produce the emulsions. The neutral red release (NRR) assay was performed as an in vitro method to evaluate the cytotoxicity of the emulsions in HaCat and 3T3 cell lines and predict potential skin irritation. The Buriti oil emulsions presented low cytotoxicity to the cells at high concentrations and the addition of Vitamin E increased cell viability. Among the surfactant tested, Unitol(R) CE 200F proved to be the most cytotoxic, presenting an IC50 significantly lower than the others. Emulsions formulated with Buriti oil and commercial surfactants could be non irritant to the skin due to their low cytotoxicity, especially when enhanced with vitamin E. When emulsified with Buriti oil, water and Brij 72, Unitol CE200F showed less cytotoxic effects than when tested alone. (C) 2008 Elsevier Ltd. All rights reserved.

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We investigated the effects of the dietary pigment chlorophyll b (CLb) on cisplatin (cDDP)-induced oxidative stress and DNA damage, using the comet assay in mouse peripheral blood cells and the micronucleus (MN) test in bone marrow and peripheral blood cells. We also tested for thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) in liver and kidney tissues, as well as catalase (CAT) activity and GSH in total blood. CLb (0.2 and 0.5 mg/kg b.w.) was administrated by gavage every day for 13 days. On the 14th day of the experiment, 6 mg/kg cDDP or saline was delivered intraperitoneally. Treatment with cDDP led to a significant decrease in DNA migration and an increase in MN frequency in both cell types, bone marrow and peripheral blood cells. In the kidneys of mice treated with cDDP, TBARS levels were increased, whereas GSH levels were depleted in kidney and liver. In mice that were pretreated with CLb and then treated with cDDP, TBARS levels maintained normal concentrations and GSH did not differ from cDDP group. The improvement of oxidative stress biomarkers after CLb pre-treatment was associated with a decrease in DNA damage, mainly for the highest dose evaluated. Furthermore, CLb also slightly reduced the frequency of chromosomal breakage and micronucleus formation in mouse bone marrow and peripheral blood cells. These results show that pre-treatment with CLb attenuates cDDP-induced oxidative stress, chromosome instability, and lipid peroxidation. (C) 2011 Elsevier B.V. All rights reserved.

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This paper describes a simple method for mercury speciation in seafood samples by LC-ICP-MS with a fast sample preparation procedure. Prior to analysis, mercury species were extracted from food samples with a solution containing mercaptoethanol, L-cysteine and HCl and sonication for 15 min. Separation of mercury species was accomplished in less than 5 min on a C8 reverse phase column with a mobile phase containing 0.05%-v/v mercaptoethanol, 0.4% m/v L-cysteine and 0.06 mol L(-1) ammonium acetate. The method detection limits were found to be 0.25, 0.20 and 0.1 ng g(-1) for inorganic mercury, ethylmercury and methylmercury, respectively. Method accuracy is traceable to Certified Reference Materials (DOLT-3 and DORM-3) from the National Research Council Canada (NRCC). With the proposed method there is a considerable reduction of the time of sample preparation. Finally, the method was applied for the speciation of mercury in seafood samples purchased from the Brazilian market. (C) 2010 Elsevier Ltd. All rights reserved.

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Modern lifestyle markedly changed eating habits worldwide, with an increasing demand for ready-to-eat foods, such as minimally processed fruits and leafy greens. Packaging and storage conditions of those products may favor the growth of psychrotrophic bacteria, including the pathogen Listeria monocytogenes. In this work, minimally processed leafy vegetables samples (n = 162) from retail market from Ribeirao Preto, Sao Paulo, Brazil, were tested for the presence or absence of Listeria spp. by the immunoassay Listeria Rapid Test, Oxoid. Two L. monocytogenes positive and six artificially contaminated samples of minimally processed leafy vegetables were evaluated by the Most Probable Number (MPN) with detection by classical culture method and also culture method combined with real-time PCR (RTi-PCR) for 16S rRNA genes of L monocytogenes. Positive MPN enrichment tubes were analyzed by RTi-PCR with primers specific for L. monocytogenes using the commercial preparation ABSOLUTET (TM) QPCR SYBR (R) Green Mix (ABgene, UK). Real-time PCR assay presented good exclusivity and inclusivity results and no statistical significant difference was found in comparison with the conventional culture method (p < 0.05). Moreover, RTi-PCR was fist and easy to perform, with MPN results obtained in ca. 48 h for RTi-PCR in comparison to 7 days for conventional method. (C) 2009 Elsevier Ltd. All rights reserved.

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The treatment of textile effluents by the conventional method based on activated sludge followed by a chlorination step is not usually an effective method to remove azo dyes, and can generate products more mutagenic than the untreated dyes. The present work evaluated the efficiency of conventional chlorination to remove the genotoxicity/mutagenicity of the azo dyes Disperse Red 1, Disperse Orange 1, and Disperse Red 13 from aqueous solutions. The comet and micronucleus assays with HepG2 cells and the Salmonella mutagenicity assay were used. The degradation of the dye molecules after the same treatment was also evaluated, using ultraviolet and visible absorption spectrum measurements (UV-vis), high performance liquid chromatography coupled to a diode-array detector (HPLC-DAD), and total organic carbon removal (TOC) analysis. The comet assay showed that the three dyes studied induced damage in the DNA of the HepG2 cells in a dose-dependent manner. After chlorination, these dyes remained genotoxic, although with a lower damage index (DI). The micronucleus test showed that the mutagenic activity of the dyes investigated was completely removed by chlorination, under the conditions tested. The Salmonella assay showed that chlorination reduced the mutagenicity of all three dyes in strain YG1041, but increased the mutagenicity of Disperse Red 1 and Disperse Orange 1 in strain TA98. With respect to chemical analysis, all the solutions showed rapid discoloration and a reduction in the absorbance bands characteristic of the chromophore group of each dye. However, the TOC was not completely removed, showing that chlorination of these dyes is not efficient in mineralizing them. It was concluded that conventional chlorination should be used with caution for the treatment of aqueous samples contaminated with azo dyes. (C) 2010 Elsevier B.V. All rights reserved.

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Acai, the fruit of a palm native to the Amazonian basin, is widely distributed in northern South America, where it has considerable economic importance. Whereas individual polyphenolics compounds in Acai have been extensively evaluated, studies of the intact fruit and its biological properties are lacking. Therefore, the present study was undertaken to investigate the in vivo genotoxicity of Acai and its possible antigenotoxicity on doxorubicin (DXR)-induced DNA damage. The Acai pulp doses selected were 3.33, 10.0 and 16.67 g/kg b.w. administered by gavage alone or prior to DXR (16 mg/kg b.w.) administered by intraperitoneal injection. Swiss albino mice were distributed in eight groups for acute treatment with acai pulp (24 h) and eight groups for subacute treatment (daily for 14 consecutive days) before euthanasia. The negative control groups were treated in a similar way. The results of chemical analysis suggested the presence of carotenoids, anthocyanins, phenolic. and flavonoids in Acai pulp. The endpoints analyzed were micronucleus induction in bone marrow and peripheral blood cells polychromatic erythrocytes, and DNA damage in peripheral blood, liver and kidney cells assessed using the alkaline (pH > 13) comet assay. There were no statistically significant differences (p > 0.05) between the negative control and the groups treated with the three doses of Acai pulp alone in all endpoints analyzed, demonstrating the absence of genotoxic effects. The protective effects of Acai pulp were observed in both acute and subacute treatments, when administered prior to DXR. In general, subacute treatment provided greater efficiency in protecting against DXR-induced DNA damage in liver and kidney cells. These protective effects can be explained as the result of the phytochemicals present in Acai pulp. These results will be applied to the developmental of food with functional characteristics, as well as to explore the characteristics of Acai as a health promoter. (C) 2009 Elsevier B.V. All rights reserved.

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Nerve and tendon gliding exercises are advocated in the conservative and postoperative management of carpal tunnel syndrome (CTS). However, traditionally advocated exercises elongate the nerve bedding substantially, which may induce a potentially deleterious strain in the median nerve with the risk of symptom exacerbation in some patients and reduced benefits from nerve gliding. This study aimed to evaluate various nerve gliding exercises, including novel techniques that aim to slide the nerve through the carpal tunnel while minimizing strain (sliding techniques). With these sliding techniques, it is assumed that an increase in nerve strain due to nerve bed elongation at one joint (e.g., wrist extension) is simultaneously counterbalanced by a decrease in nerve bed length at an adjacent joint (e.g., elbow flexion). Excursion and strain in the median nerve at the wrist were measured with a digital calliper and miniature strain gauge in six human cadavers during six mobilization techniques. The sliding technique resulted in an excursion of 12.4 mm, which was 30% larger than any other technique (p 0.0002). Strain also differed between techniques (p 0.00001), with minimal peak values for the sliding technique. Nerve gliding associated with wrist movements can be considerably increased and nerve strain substantially reduced by simultaneously moving neighboring joints. These novel nerve sliding techniques are biologically plausible exercises for CTS that deserve further clinical evaluation. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:972-980, 2007

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Inaccurate species identification confounds insect ecological studies. Examining aspects of Trichogramma ecology pertinent to the novel insect resistance management strategy for future transgenic cotton, Gossypium hirsutum L., production in the Ord River Irrigation Area (ORIA) of Western Australia required accurate differentiation between morphologically similar Trichogramma species. Established molecular diagnostic methods for Trichogramma identification use species-specific sequence difference in the internal transcribed spacer (ITS)-2 chromosomal region; yet, difficulties arise discerning polymerase chain reaction (PCR) fragments of similar base pair length by gel electrophoresis. This necessitates the restriction enzyme digestion of PCR-amplified ITS-2 fragments to readily differentiate Trichogramma australicum Girault and Trichogramma pretiosum Riley. To overcome the time and expense associated with a two-step diagnostic procedure, we developed a “one-step” multiplex PCR technique using species-specific primers designed to the ITS-2 region. This approach allowed for a high-throughput analysis of samples as part of ongoing ecological studies examining Trichogramma biological control potential in the ORIA where these two species occur in sympatry.

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Different interceptive tasks and modes of interception (hitting or capturing) do not necessarily involve similar control processes. Control based on preprogramming of movement parameters is possible for actions with brief movement times but is now widely rejected; continuous perceptuomotor control models are preferred for all types of interception. The rejection of preprogrammed control and acceptance of continuous control is evaluated for the timing of rapidly executed, manual hitting actions. It is shown that a preprogrammed control model is capable of providing a convincing account of observed behavior patterns that avoids many of the arguments that have been raised against it. Prominent continuous perceptual control models are analyzed within a common framework and are shown to be interpretable as feedback control strategies. Although these models can explain observations of on-line adjustments to movement, they offer only post hoc explanations for observed behavior patterns in hitting tasks and are not directly supported by data. It is proposed that rapid manual hitting tasks make up a class of interceptions for which a preprogrammed strategy is adopted-a strategy that minimizes the role of visual feedback. Such a strategy is effective when the task demands a high degree of temporal accuracy.

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The calculation of quantum dynamics is currently a central issue in theoretical physics, with diverse applications ranging from ultracold atomic Bose-Einstein condensates to condensed matter, biology, and even astrophysics. Here we demonstrate a conceptually simple method of determining the regime of validity of stochastic simulations of unitary quantum dynamics by employing a time-reversal test. We apply this test to a simulation of the evolution of a quantum anharmonic oscillator with up to 6.022×1023 (Avogadro's number) of particles. This system is realizable as a Bose-Einstein condensate in an optical lattice, for which the time-reversal procedure could be implemented experimentally.

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1. The response of the diaphragm to the postural perturbation produced by rapid flexion of the shoulder to a visual stimulus was evaluated in standing subjects. Gastric, oesophageal and transdiaphragmatic pressures were measured together with intramuscular and oesophageal recordings of electromyographic activity (EMG) in the diaphragm. To assess the mechanics of contraction of the diaphragm, dynamic changes in the length of the diaphragm were measured with ultrasonography. 2. With rapid flexion of the shoulder in response to a visual stimulus, EMG-activity in the costal and crural diaphragm occurred about 20 ms prior to the onset of deltoid EMG. This anticipatory contraction occurred irrespective of the phase of respiration in which arm movement began. The onset of diaphragm EMG-coincided with that of transversus abdominis. 3. Gastric and transdiaphragmatic pressures increased in association with the rapid arm flexion by 13.8 +/- 1.9 (mean +/- S.E.M.) and 13.5 +/- 1.8 cmH(2)O, respectively. The increases occurred 49 +/- 4 ms after the onset of diaphragm EMG, but preceded the onset of movement of the limb by 63 +/- 7 ms. 4. Ultrasonographic measurements revealed that the costal diaphragm shortened and then lengthened progressively during the increase in transdiaphragmatic pressure. 5. This study provides definitive evidence that the human diaphragm is involved in the control of postural stability during sudden voluntary movement of the limbs.

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