992 resultados para LIVE-ANIMAL ULTRASOUND


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An ultrasound-assisted synthesis of functionalized symmetrical biaryls with electron-withdrawing or electron-donating substituents is described and illustrated by the palladium-catalyzed detelluration of 1,2-diarylditellanes. This procedure offers easy access to symmetrical biaryls in short reaction time and the products are achieved in good to excellent yields. (c) 2009 Published by Elsevier Ltd.

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An ultrasound-assisted synthesis of symmetrical biaryls with electron-withdrawing or -donating substituents is described and illustrated by palladium-catalyzed homocoupling reaction of aryl tellurides. This procedure offers easy access to biaryls in short reaction time, and the products are achieved in good to excellent yields.

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In vitro skin permeation of hyaluronidase enzyme and the ultrasound (US) effects on cutaneous permeation of this enzyme were investigated. Diffusion cell technique, porcine skins, buffer solution, and a hydrophilic gel+hyaluronidase (100 TUR/g), were used for study. The experimental groups were: gel+enzyme and gel+enzyme+US. The activity of permeated hyaluronidase was determined by turbydimetric method in spectrophotometer at 400nm. Gel+enzyme group permitted a diffusion of 26.89 +/- 3.82 TUR of hyaluronidase in the total time of 240 minutes. However, the other group did not produce significant differences (p0.05) in the same period (13.68 +/- 5.35 TUR). Hyaluronidase permeation through the skin was verified; however US did not cause increase of this enzyme permeation.

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An ultrasound-assisted synthesis of functionalized 1,3-enyne scaffolds is described and illustrated by palladium-catalyzed cross-coupling of potassium alkynyltrifluoroborate salts and alpha-styrylbutyltellurides. This procedure offers easy access to 1,3-enyne architecture that contains aliphatic and aromatic groups in good to excellent yields.

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Objectives In the present study we investigated the anti nociceptive, anti-inflammatory and antipyretic effects of 7-hydroxycoumarin (7-HC) in animal models. Methods The effects of oral 7-HC were tested against acetic acid-induced writhing, formalin test, tail flick test, complete Freund`s adjuvant (CFA)-induced hypemociception, carrageenan-induced paw oedema, lipopolysaccharide-induced fever and the rota rod test. Key findings 7-HC (3-60 mg/kg) produced a dose-related antinociception against acetic acid-induced writhing in mice and in the formalin test. In contrast, treatment with 7-HC did not prevent thermal nociception in the tail flick test. A single treatment with 7-HC, 60 mg/kg, produced a long-lasting antinociceptive effect against CFA-induced hypernociception, a chronic inflammatory pain stimulus. Notably, at 60 mg/kg per day over 4 days the administration of 7-HC produced a continuous antinociceptive effect against CFA-induced hypernociception. 7-HC (30-120 mg/kg) produced anti-inflammatory and antipyretic effects against carrageenan-induced inflammation and lipopolysaccharide-induced fever, respectively. Moreover, 7-HC was found to be safe with respect to ulcer induction. In the rota rod test, 7-HC-treated mice did not show any motor performance alterations. Conclusions The prolonged antinociceptive and anti-inflammatory effects of 7-HC, in association with its low ulcerogenic activity, indicate that this molecule might be a good candidate for development of new drugs for the control of chronic inflammatory pain and fever.

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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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P>With the evidence showing the protection variability of bacille Calmette-Guerin, new potential vaccines for tuberculosis have been tested around the world. One of the general concerns in tuberculosis vaccine development is the possibility of priming the host immune system with prior exposure to environmental mycobacteria antigens, which can change the efficacy of subsequent vaccination. As there is a great homology between the species from Mycobacterium genera, the previous contact of experimental animals with environmental mycobacteria could sensitize the mice and, in this way, could influence subsequent vaccine research. The aim of our study was to investigate critical points in an animal facility to search for environmental mycobacteria that eventually could be in direct or indirect contact with the experimental animals. Samples were collected from surfaces of walls, floor, animal cages and shelves and analysed using the Ogawa-Kudoh decontamination method. Samples of drinking water, food and sawdust were collected for analysis by the NALC/NaOH decontamination method. Also, the samples were cultivated directly in broth medium, without any method for decontamination. After decontamination methods, we observed bacterial colony growth in 4.31% of the total of samples analysed. These samples were stained with Ziehl-Neelsen and we did not detect any acid-fast bacilli, suggesting that the animal facility analysed is free from contamination by environmental mycobacteria and is not a source of mycobacterial antigens. Furthermore, our study showed a new paradigm in tuberculosis vaccine development: concern about the animal facility environment in terms of immune system priming of experimental animals by nascent bacterial contaminants.

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We developed a new method for the quantification of parasites in tissue. Trypanosoma cruzi strain CL parasites were genetically engineered to express the Escherichia coli beta-galactosidase gene, lacZ and this enzyme is able to catalyze a colorimetric reaction with chlorophenol red beta-d galactopyranoside (CPRG) as the substrate. The animals were infected with clone CL Brener strain B5 of T. cruzi and treated with benznidazole in order to verify the reduction in the number of parasites in tissue study by quantifying the enzyme beta-galactosidase. The assay demonstrates a reduction in the number of parasites in the groups treated. Thus, this test can be used to test other substances with the aim of verifying the effectiveness in the chronic phase of experimental Chagas` disease.

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The genus Cryptococcus includes free-developing species, a few of which are of medical importance. Some, such as C. neoformans and C. gattii, cause infections in man frequently and C. albidus and C. laurentii cause less so. The aims of this study were to evaluate organ colonization after inoculation of C. albidus and C. laurentii isolates in normal BALB/c mice, the virulence factors (growth at 37A degrees C, capsule, melanin, proteinase, and phospholipase production) and the molecular profile (PCR-fingerprinting) of the yeasts before and after infection. The importance of different profiles (virulence and molecular) was considered in relation to the distribution in different organs and to the time intervals of isolation from organs. C. albidus was isolated from animal organs 2 to 10 days after inoculation and C. laurentii from 2 to 120 days. Most isolates of the two species kept the virulence factors showed before inoculation. The high homogeneity of the molecular profile of C. albidus and the high heterogeneity of C. laurentii were kept through the passages in animals. It is concluded that most isolates of both species were recovered from the animal organs after 5 or more days, and phenotypes were not altered by inoculation. No molecular alteration was detected and the virulence factors were not related to the time intervals before isolation from organs.

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This study compared the effects of live, taped, and no music, on agitation and orientation levels of people experiencing posttraumatic amnesia (PTA). Participants (N = 22) were exposed to all 3 conditions, twice over 6 consecutive days. Songs used in the live and taped music conditions were identical and were selected based on participants' own preferred music. Pre and posttesting was conducted for each condition using the Agitated Behavior Scale (Corrigan, 1989) and the Westmead PTA Scale (Shores, Marosszeky, Sandanam, Batchelor, 1986). Participants' memory for the music used was also tested and compared with their memory for pictorial material presented in the Westmead PTA Scale. Results indicate that music significantly reduced agitation (p

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Subtropical grasslands are low in organic matter digestibility (OMD) (0.60) and nitrogen (N) (15 g/kg) for much of the year and this limits cattle production which is characterized by low calving rates and low weaning weights. Production has been based on Bos taurus British breeds of cattle but this is changing and now many breeding herds comprise B, indicus cows and their crosses. This change has increased some aspects of production, but low calving rates persist. A 4-year study was undertaken with a view to improve calving rates and weaner output by supplementing cows grazing either native or improved pastures with a high protein oilseed meal (cottonseed meal; CSM) on four sites. These sites were subdivided into a total of 36 paddocks to allow for two replications in a 3 breeds X 3 supplementation rates X 2 pastures factorial design. Selected cows (no. = 216) from Hereford (H), Brahman (B) and Brahman X Hereford (BH) breed types were set to graze either native pastures (0.45 to 0.62 OMD, 8 to 15 g N per kg; low quality) or improved pastures (0.47 to 0.67 OA ID, 10 to 22 g N per kg; medium quality). Cows were given either 0, 750 or 1500 g/day of CSM for 130 days from calving until 4 weeks into a 12- to 13-week mating period. The CSM was given as two meals per week. Live weight at mating of cows on the low quality pasture was increased (P < 0.01) over those not supplemented by feeding either 750 g CSM per day (H and B cows) or 1500 g CSM per day tall cows). There was no significant effect of supplementation on the mating weights of B cows grazing the medium quality sites. Calving rate of B cows was not increased by their supplementation on either low (4-year mean 58.3 %) or medium quality pastures (66.8%) but did tend to be higher in H cows when supplemented at 1500 g CSM per day on the low (66.7 v. 78.0 (s.e. 6.09) %; P < 0.1) and medium quality pastures (70.5 v. 93.5 (s.e. 4.72) %). An increased calving rate (65.8 (s.e. 6.6) % to 83.2 (s.e. 5.82) % in supplemented BH cows grazing low quality pastures approached significance (P < 0.1) when given CSM at 1500 g/day but there was no increased trend in calving rate when this breed type was supplemented on medium quality pastures. Weaning weights of calves from and B and BH cows were increased (P < 0.05) by supplementation of their darns at 750 g/day and for calves weaned from H cows supplemented at 1500 g/day of CSM. Supplementation at 1500 g/day on low quality pastures increased weaner output per cow mated by 120% for H, by 65% for BH cows and by 50% for B cows. Weaner output was increased by 34 and 40%, respectively, for B and H cows when supplemented at 750 g/day and grazing medium quality pastures but there teas no significant effect of supplementation on output from BH cows. Responses in many parameters differed between years. These results were interpreted as a response to the protein in the oilseed meal supplement by B, taurus and B. taurus X B. indicus cross cows grazing on the subtropical pastures. The study also highlighted that responses to the meal differed between breed types, between the quality of the grazed pasture and between the years of supplementation.

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Plants collected from diverse sites on subantarctic Macquarie Island varied by up to 30 parts per thousand in their leaf delta(15)N values. N-15 natural abundance of plants, soils, animal excrement and atmospheric ammonia suggest that the majority of nitrogen utilised by plants growing in the vicinity of animal colonies or burrows is animal-derived. Plants growing near scavengers and animal higher in the food chain had highly enriched delta(15)N values (mean = 12.9 parts per thousand), reflecting the highly enriched signature of these animals' excrement, while plants growing near nesting penguins and albatross, which have an intermediate food chain position, had less enriched delta(15)N values (> 6 parts per thousand). Vegetation in areas affected by rabbits had lower delta(15)N values (mean = 1.2 parts per thousand), while the highly depleted delta(15)N values (below -5 parts per thousand) of plants at upland plateau sites inland of penguin colonies, suggested that a portion of their nitrogen is derived from ammonia (mean N-15 = -10 parts per thousand) lost during the degradation of penguin guano. Vegetation in a remote area had delta(15)N values near -2 parts per thousand. These results contrast with arctic and subarctic studies that attribute large variations in plant N-15 values to nitrogen partitioning in nitrogen-limited environments. Here, plant N-15 reflects the N-15 Of the likely nitrogen sources utilised by plants.