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481.
ABSTRACTA range of studies have demonstrated that regular drinkers respond to alcohol-related stimuli with increased self-reported craving for alcohol (cue-reactivity). Considerable individual differences have been found in terms of the magnitude of the craving response. However, less work has been conducted to assess the role of cognitive factors in influencing alcohol cue-elicited craving. This study assessed the effect of a cognitive distraction task and individual variability in trait-mindfulness on responses to alcohol cues using a standard cue reactivity paradigm. Sixty-nine regular social drinkers were randomly allocated to one of the two experimental conditions – no instructions vs cognitive distraction (asked to focus on milk) – and were presented with alcohol. Results indicated that positive craving (i.e., desire to drink for positive reinforcement) increased from neutral to alcohol-cue exposure, and that those in the cognitive distraction condition reported significantly lower positive urge to drink after alcohol-cue exposure. No relationship between alcohol craving and mindfulness was found. Implications of the findings are discussed with a particular focus on the role of cognitive distraction in cue-reactivity and the potential utility of using a cognitive distraction technique to reduce alcohol craving. 相似文献
482.
483.
C J Nic Fhogartaigh S Vargas-Prada V Huancaré S Lopez J Rodríguez D A J Moore 《The international journal of tuberculosis and lung disease》2008,12(5):555-560
SETTING: Laboratorio de Investigación de Enfermedades Infecciosas, Universidad Peruana Cayetano Heredia (UPCH) and government health centres, Lima, Peru. OBJECTIVE: To evaluate the contribution of unselected (courtesy) microscopic observation drug susceptibility (MODS) testing to the diagnosis and/or drug susceptibility testing (DST) of tuberculosis and their subsequent impact upon patient management. DESIGN: Retrospective database analysis and case note review of MODS culture-positive cases. RESULTS: Mycobacterium tuberculosis was isolated in 28.9% of 225 samples (209 patients); 22.2% of 63 positive cases were multidrug-resistant. In 58 MODS culture-positive cases with follow-up data available, MODS provided culture confirmation of diagnosis, DST or both in 82.8%, before any standard method. In 41.4%, this result should have prompted a modification in patient management. Delays between laboratory result and initiation or change of treatment, where applicable, took on average 42 and 64 days, respectively, of which a delay of respectively 17 and 48 days occurred after the receipt of results by the health facility. CONCLUSION: MODS provides important data for clinical management within a meaningful timeframe and should contribute positively to patient outcomes due to earlier initiation of appropriate therapy. Although clinicians may successfully select patients likely to benefit from MODS, ongoing work is required to identify optimal implementation of the assay and to reduce logistical and health system derived delays. 相似文献
484.
Noemia Pereira da Silva Santos Silene Carneiro Nascimento Marcela Silvestre Outtes Wanderley Nicodemos Teles Pontes-Filho José Figueiredo da Silva Célia Maria Machado Barbosa de Castro Eugênia Cristina Pereira Nicácio Henrique da Silva Neli Kika Honda Nereide Stela Santos-Magalh?es 《European journal of pharmaceutics and biopharmaceutics》2006,64(2):154-160
Despite the recognised antiproliferative and antitumour properties of usnic acid, its therapeutic application has yet to be introduced. In fact, the high hepatotoxicity and low water solubility of usnic acid have somewhat restricted its practical use in anticancer therapy. The aim of this study was therefore to investigate the antitumour activity of usnic acid encapsulated into nanocapsules prepared with lactic co-glycolic acid polymer. Usnic acid-loaded nanocapsules were obtained using the interfacial deposition of a preformed polymer. The antitumour activity was confirmed on an ascitic tumour (Sarcoma-180) implanted in Swiss mice and estimated by means of the tumour inhibition. The results of antitumour activity confirmed that the encapsulation of usnic acid into PLGA-nanocapsules produced a 26.4% increase in tumour inhibition as compared with the standard free usnic acid treatment. Vacuolization of hepatocytes and a mild lymphocytic infiltration in portal spaces were observed in animals treated with free usnic acid. However, this hepatotoxicity was substantially reduced when animals were treated with usnic acid-loaded nanocapsules. No histological changes were noticed in the kidneys or spleen of animals treated either with usnic acid or usnic acid-loaded nanocapsules. These results suggest that nanoencapsulation may be a way of enabling usnic acid to be used in chemotherapy. 相似文献
485.
486.
Merel van den Broek Loek J.M. de Heide Marloes Emous Ragnhild B. Wijma Nic J.G.M. Veeger Albert Wolthuis Anke J. Laskewitz M. Rebecca Heiner-Fokkema Anneke C. Muller Kobold Bruce H.R. Wolffenbuttel André P. van Beek 《Surgery for obesity and related diseases》2018,14(8):1106-1117
Background
Circulating amino acids have been associated with both appetite and the secretion of anorexigenic hormones in healthy and obese populations. This effect has not been investigated in subjects having undergone Roux-en-Y gastric bypass surgery (RYGB).Objective
To investigate the association between postprandial plasma concentrations of amino acids and the anorexigenic hormones glucagon-like peptide-1 (GLP-1) and peptide tyrosine tyrosine (PYY), the orexigenic hormone ghrelin, and satiety and hunger in post-RYGB subjects.Setting
A Dutch surgical department.Methods
Participants after primary RYGB were studied during a Mixed Meal Tolerance Test (MMTT). Satiety and hunger were assessed every 30 minutes on visual analogue scales. Blood samples were collected at baseline, every 10 minutes during the first half hour and every 30 minutes until 210 minutes after the start. The samples were assessed for 24 amino acids and 3 gastrointestinal hormones. Incremental areas under the curve (iAUCs) were calculated. Exploratory analyses were performed in which subjects were divided into high and low responders depending on the median iAUC.Results
42 subjects, aged 48 ± 11 (mean ± SD) years, 31 to 76 months post-RYGB and with total weight loss of 30 ± 9% completed the MMTT. Subjects with high satiety scores had more than a 25% higher net iAUC of PYY and GLP-1 and at least a 10% higher net iAUC of 10 amino acids compared to subjects with low scores (P < 0.05). The net iAUC of five of these amino acids (i.e. arginine, asparagine, histidine, serine and threonine) was more than 10% higher in subjects with high responses on GLP-1 and/or PYY (P < 0.05).Conclusions
Certain postprandial amino acids were associated with satiety and anorexigenic hormones and could therefore play a role in appetite regulation after RYGB; either by a direct effect on satiety, indirectly through gastrointestinal hormones, or both. 相似文献487.
488.
Assessing fitness costs for transgenic Aedes aegypti expressing the GFP marker and transposase genes
Irvin N Hoddle MS O'Brochta DA Carey B Atkinson PW 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(3):891-896
The development of transgenic mosquitoes that are refractory to the transmission of human diseases such as malaria, dengue, and yellow fever has received much interest due to the ability to transform a number of vector mosquito species with transposable elements. Transgenic strains of mosquitoes have been generated with molecular techniques that exhibit a reduced capacity to transmit pathogens. These advancements have led to questions regarding the fitness of transgenic mosquitoes and the ability of transformed mosquitoes to compete and effectively spread beneficial genes through nontransformed field populations, the core requirement of a genetically based control strategy aimed at reducing the spread of mosquito-borne human disease. Here we examine the impact of transgenesis on the fitness of Aedes aegypti, a mosquito that transmits yellow fever. Mosquitoes were altered with two types of transgene, the enhanced GFP gene and two transposase genes from the Hermes and MOS1 transposable elements. We examined the effects of these elements on the survivorship, longevity, fecundity, sex ratio, and sterility of transformed mosquitoes and compared results to the nontransformed laboratory strain. We show that demographic parameters are significantly diminished in transgenic mosquitoes relative to the untransformed laboratory strain. Reduced fitness in transgenic mosquitoes has important implications for the development and utilization of this technology for control programs based on manipulative molecular modification. 相似文献
489.
Martin E W Hemels Trudeke Van Noord Harry J G M Crijns Dirk J Van Veldhuisen Nic J G M Veeger Hans A Bosker Ans C P Wiesfeld Maarten P Van den Berg Adelita V Ranchor Isabelle C Van Gelder 《Journal of the American College of Cardiology》2006,48(5):1001-1009
OBJECTIVES: The VERDICT (Verapamil Versus Digoxin and Acute Versus Routine Serial Cardioversion Trial) is a prospective, randomized study to investigate whether: 1) acutely repeated serial electrical cardioversions (ECVs) after a relapse of atrial fibrillation (AF); and 2) prevention of intracellular calcium overload by verapamil, decrease intractability of AF. BACKGROUND: Rhythm control is desirable in patients suffering from symptomatic AF. METHODS: A total of 144 patients with persistent AF were included. Seventy-four (51%) patients were randomized to the acute (within 24 h) and 70 (49%) patients to the routine serial ECVs, and 74 (51%) patients to verapamil and 70 (49%) patients to digoxin for rate control before ECV and continued during follow-up (2 x 2 factorial design). Class III antiarrhythmic drugs were used after a relapse of AF. Follow-up was 18 months. RESULTS: At baseline, there were no significant differences between the groups, except for beta-blocker use in the verapamil versus digoxin group (38% vs. 60%, respectively, p = 0.01). At follow-up, no difference in the occurrence of permanent AF between the acute and the routine cardioversion groups was observed (32% [95% confidence intervals (CI)] 22 to 44) vs. 31% [95% CI 21 to 44], respectively, p = NS), and also no difference between the verapamil- and the digoxin-randomized patients (28% [95% CI 19 to 40] vs. 36% [95% CI 25 to 48] respectively, p = NS). Multivariate Cox regression analysis revealed that lone digoxin use was the only significant predictor of failure of rhythm control treatment (hazard ratio 2.2 [95% CI 1.1 to 4.4], p = 0.02). CONCLUSIONS: An acute serial cardioversion strategy does not improve long-term rhythm control in comparison with a routine serial cardioversion strategy. Furthermore, verapamil has no beneficial effect in a serial cardioversion strategy. 相似文献
490.