802 resultados para Ast-87077


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Oberon-2 is an object-oriented language with a class structure based on type extension. The runtime structure of Oberon-2 is described and the low-level mechanism for dynamic type checking explained. It is shown that the superior type-safety of the language, when used for programming styles based on heterogeneous, pointer-linked data structures, has an entirely negligible cost in runtime performance.

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Alcohol use disorders (AUDs) impact millions of individuals and there remain few effective treatment strategies. Despite evidence that neuronal nicotinic acetylcholine receptors (nAChRs) have a role in AUDs, it has not been established which subtypes of the nAChR are involved. Recent human genetic association studies have implicated the gene cluster CHRNA3-CHRNA5-CHRNB4 encoding the α3, α5, and β4 subunits of the nAChR in susceptibility to develop nicotine and alcohol dependence; however, their role in ethanol-mediated behaviors is unknown due to the lack of suitable and selective research tools. To determine the role of the α3, and β4 subunits of the nAChR in ethanol self-administration, we developed and characterized high-affinity partial agonists at α3β4 nAChRs, CP-601932, and PF-4575180. Both CP-601932 and PF-4575180 selectively decrease ethanol but not sucrose consumption and operant self-administration following long-term exposure. We show that the functional potencies of CP-601932 and PF-4575180 at α3β4 nAChRs correlate with their unbound rat brain concentrations, suggesting that the effects on ethanol self-administration are mediated via interaction with α3β4 nAChRs. Also varenicline, an approved smoking cessation aid previously shown to decrease ethanol consumption and seeking in rats and mice, reduces ethanol intake at unbound brain concentrations that allow functional interactions with α3β4 nAChRs. Furthermore, the selective α4β2(*) nAChR antagonist, DHβE, did not reduce ethanol intake. Together, these data provide further support for the human genetic association studies, implicating CHRNA3 and CHRNB4 genes in ethanol-mediated behaviors. CP-601932 has been shown to be safe in humans and may represent a potential novel treatment for AUDs.

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拟南芥ast (anthocyanin spotted testa) 突变体是由碳离子束诱导产生的与花青苷生物合成有关的突变体,受单隐性核基因控制。由于花青苷的异常积累,突变体未成熟种子的种皮呈现紫红色的斑点;野生型植株幼嫩的种皮没有花青苷的异常积累,呈淡绿色。初步作图分析表明,AST基因定位于拟南芥第I号染色体上,并且位于SSLP分子标记nga280和CAPS分子标记PAB5之间。 AST基因与SSLP分子标记nga280紧密连锁,遗传距离为3.2cM;与CAPS分子标记PAB5相距较远,遗传距离为21.1cM。 采用DDRT-PCR的策略,分析野生型与突变型植株未成熟角果中基因表达的差异。通过调整DDRT-PCR中总RNA、锚定引物、随机引物、cDNA和dNTP等关键试剂的用量,优化了适用于银染检测的DDRT-PCR方法。PCR扩增产物经6%变性聚丙烯酰胺凝胶垂直电泳分离后,银染能检测到多而清晰的条带。泳道中的条带数最少为40个,最多达80个,平均为60个,条带大小分布在100bp-900bp范围,银染的灵敏度为5pg/mm2。此方法操作简便快速,灵敏度高,重复性好。采用这个改良的的方法,分析了拟南芥野生型和ast突变型植株未成熟角果中16,000个cDNA扩增产物条带,从中筛选出28个差异条带。二次PCR扩增后,进一步筛选出10个差异表达的cDNA条带,其中6个是野生型特异表达的,4个是突变型特异表达的。对这10个差异片段进行测序。BLASTN分析表明,这10个差异表达的cDNA片段与数据库中花青苷生物合成途径中的结构基因和调节基因序列没有同源性,表明用DDRT-PCR的方法克隆特定的AST基因有一定的局限性。 利用图位克隆(map-based cloning)的策略,对拟南芥AST 基因进行克隆。根据拟南芥数据库中的SNPs (simple nucleotide polymophisms) 序列和插入/缺失多态性(insertion/deletion polymorphisms)序列,设计了一系列分子标记。利用这些分子标记,对600个F2代有突变表型的植株进行重组子筛选,完成了对拟南芥AST基因的精细作图,成功地将AST 基因定位到BAC克隆T13M11上。初步确定该BAC克隆中的基因T13M11.8 可能是AST基因。该基因的DNA序列长1432bp,含有6个外显子和5个内含子,编码的蛋白与花青苷生物合成途径中的二氢黄酮醇4-还原酶有较高的同源性。功能互补实验正在进行当中。

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A new VITEK 2 antibiotic susceptibility testing (AST) card, AST N-054, was introduced for aerobic gram-negative bacilli in 2007 and has been widely adopted for routine use in the UK. We evaluated its performance for detecting extended-spectrum beta-lactamase (ESBL) production in Escherichia coli.

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The pathogenesis of hepatic encephalopathy is multifactorial, involving gut-derived toxins such as ammonia, which has been demonstrated to induce oxidative stress. Therefore, a primary hepatic encephalopathy treatment target is reducing ammonia production in the gastrointestinal tract. AST-120, an oral adsorbent of engineered activated carbon microspheres with surface areas exceeding 1600 m(2) /g, acts as a sink for neurotoxins and hepatotoxins present in the gut. We evaluated the capacity of AST-120 to adsorb ammonia in vitro and to lower blood ammonia, oxidative stress and brain edema in cirrhotic rats. Cirrhosis was induced in rats by bile duct ligation for 6 weeks. AST-120 was administered by gavage preventively for 6 weeks (0.1, 1, and 4 g/kg/day). In addition, AST-120 was evaluated as a short-term treatment for 2 weeks and 3 days (1 g/kg/day) and as a sink to adsorb intravenously infused ammonium acetate. In vitro, AST-120 efficiently adsorbed ammonia. Ammonia levels significantly decreased in a dose-dependent manner for all AST-120-treated bile duct-ligated rats (nontreated: 177.3 ± 30.8 μM; AST-120, 0.1 g/kg/day: 121.9 ± 13.8 μM; AST-120, 1 g/kg/day: 80.9 ± 30.0 μM; AST-120, 4 g/kg/day: 48.8 ± 19.6 μM) and significantly correlated with doses of AST-120 (r = -0.6603). Brain water content and locomotor activity normalized after AST-120 treatments, whereas arterial reactive oxygen species levels remained unchanged. Furthermore, AST-120 significantly attenuated a rise in arterial ammonia after ammonium acetate administration (intravenously). Conclusion:AST-120 treatment decreased arterial ammonia levels, normalized brain water content and locomotor activity but did not demonstrate an effect on systemic oxidative stress. Also, AST-120 acts as an ammonia sink, efficiently removing blood-derived ammonia. Additional studies are warranted to evaluate the effects of AST-120 on hepatic encephalopathy in patients with advanced liver disease. (HEPATOLOGY 2011;).

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Se pone en com??n una experiencia educativa llevada a cabo con alumnado de 2.?? curso de Educaci??n Primaria en la isla de Tenerife. Lleva por t??tulo "Ideafix's restaurant" y nace, prioritariamente, ante el tedio que provoca en escolares el trabajo con el Sistema M??trico Decimal (SMD). Se desarrolla el trabajo cooperativo e interdisciplinar por competencias, desde las ??reas de matem??ticas, lengua castellana, conocimiento del medio, educaci??n pl??stica y visual y educaci??n para la ciudadan??a . A trav??s de las aventuras de los personajes de c??mic Ast??rix y Ob??lix, los diversos grupos trabajan un conjunto de actividades y un proyecto final en el que cada uno debe crear su propio negocio.

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Creatine kinase (CK) and aspartate aminotransferase (AST) are mainly muscle-specific enzymes, which can be associated with muscle tissue damage. The aim of this study was to assess the activities of CK and AST during the postoperative period, after conventional (G1) and videolaparoscopic ovariectomy (G2), in queens. A further group (G3) was subjected to anaesthesia only. Results demonstrate that there were significant differences between groups. The highest levels of CK were recorded in Gl, however at a confidence level of p < 0.05 there was no significant difference between groups during the first 6 hours after surgery. A significant (p < 0.05) increase of CK values was identified between 0h and 3h in both groups (Gl and G2). Regarding AST activity there was no significant variation between groups, but again there was a significant difference between values at 0h and 3h after surgery. In conclusion, ovariectomy performed by videolap-aroscopy seems to cause less muscle damage when compared to the conventional method. © 2009 by Verlag Hans Huber, Hogrefe AG, Bem.

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Recent research seeking to elucidate the possible effects of different types of physical training on the morphological adaptations of skeletal muscle. Although it is relatively easy to study the effects of exercise training in humans, such research becomes limited due to the invasive nature of the biopsies and the risk inherent in the use of human subjects. Thus, the application of animal models of training has been considered an appropriate strategy for the study of muscular adaptations in response to exercise. Objective: This study used a rodent model to determine the possible effects of aerobic and strength training on the CSA of fibers of the plantaris muscle. Methods: 24 male Wistar rats (80 to 120 days, 250 to 400 g) were randomly divided into 3 groups: aerobic training (TA, n = 8), strength training (ST, n = 8) and control (CO, n = 8). The animals in groups TA and TF were subjected to 8 weeks of training, while the animals of group C remained without any stimulus from start to finish the training period. At the end of the experiment, the animals were sacrificed and right plantar muscles dissected and removed. For morphological and morphometric analysis of muscle fibers was performed staining was performed H.E. Results: There was no significant difference in initial body weight between experimental groups. After 8 weeks of training, the TA group showed a significant reduction in final body weight, compared to CO and TF groups. With respect to the CSA of fibers of the plantaris muscle, no significant difference between the groups CO and TA. On the other hand, the strength training promoted a significant increase in AST of the group TF in compared with the groups CO and TA. Conclusion: Strength training used in this study promoted an increase in CSA of fibers of the plantaris muscle. On the other hand, animals submitted to aerobic training showed no changes in the CSA of the fibers, however, there was reduction in PC animals. The data strongly suggest the use of animal model of strength training used in this study as an appropriate strategy for studying the hypertrophic response of skeletal muscle.

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Rangelia vitalii is a protozoon that causes diseases in dogs, and anemia is the most common laboratory finding. However, few studies on the biochemical changes in dogs infected with this protozoon exist. Thus, this study aimed to investigate the biochemical changes in dogs experimentally infected with R. vitalii, during the acute phase of the infection. For this study, 12 female dogs (aged 6-12 months and weighing between 4 and 7 kg) were used, divided in two groups. Group A was composed of healthy dogs (n = 5); and group B consisted of infected animals (n = 7). Blood samples were collected on days 0, 10, 20 and 30 after infection, using tubes without anticoagulant to obtain serum and analyze the biochemical parameters. An increase in alanine aminotransferase (ALT) on day 20 (P < 0.05) was observed. Also, increased creatine kinase (CK) and aspartate aminotransferase (AST) levels were observed throughout the experimental period (P < 0.05). No changes in the serum gamma-glutamyltransferase, urea and creatinine levels were observed. Thus, is possible to conclude that experimental infection with R. vitalii in dogs causes changes to the biochemical profile, with increased ALT, AST and CK enzyme levels.

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BACKGROUND AND AIMS We investigated the association between significant liver fibrosis, determined by AST-to-platelet ratio index (APRI), and all-cause mortality among HIV-infected patients prescribed antiretroviral therapy (ART) in Zambia METHODS: Among HIV-infected adults who initiated ART, we categorized baseline APRI scores according to established thresholds for significant hepatic fibrosis (APRI ≥1.5) and cirrhosis (APRI ≥2.0). Using multivariable logistic regression we identified risk factors for elevated APRI including demographic characteristics, body mass index (BMI), HIV clinical and immunologic status, and tuberculosis. In the subset tested for hepatitis B surface antigen (HBsAg), we investigated the association of hepatitis B virus co-infection with APRI score. Using Kaplan-Meier analysis and Cox proportional hazards regression we determined the association of elevated APRI with death during ART. RESULTS Among 20,308 adults in the analysis cohort, 1,027 (5.1%) had significant liver fibrosis at ART initiation including 616 (3.0%) with cirrhosis. Risk factors for significant fibrosis or cirrhosis included male sex, BMI <18, WHO clinical stage 3 or 4, CD4+ count <200 cells/mm(3) , and tuberculosis. Among the 237 (1.2%) who were tested, HBsAg-positive patients had four times the odds (adjusted odds ratio, 4.15; 95% CI, 1.71-10.04) of significant fibrosis compared HBsAg-negatives. Both significant fibrosis (adjusted hazard ratio 1.41, 95% CI, 1.21-1.64) and cirrhosis (adjusted hazard ratio 1.57, 95% CI, 1.31-1.89) were associated with increased all-cause mortality. CONCLUSION Liver fibrosis may be a risk factor for mortality during ART among HIV-infected individuals in Africa. APRI is an inexpensive and potentially useful test for liver fibrosis in resource-constrained settings. This article is protected by copyright. All rights reserved.

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Samuel Meisels