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151.
Animal studies point to an implication of the endocannabinoid system on executive functions. In humans, several studies have suggested an association between acute or chronic use of exogenous cannabinoids (Δ9-tetrahydrocannabinol) and executive impairments. However, to date, no published reports establish the relationship between endocannabinoids, as biomarkers of the cannabinoid neurotransmission system, and executive functioning in humans. The aim of the present study was to explore the association between circulating levels of plasma endocannabinoids N-arachidonoylethanolamine (AEA) and 2-Arachidonoylglycerol (2-AG) and executive functions (decision making, response inhibition and cognitive flexibility) in healthy subjects. One hundred and fifty seven subjects were included and assessed with the Wisconsin Card Sorting Test; Stroop Color and Word Test; and Iowa Gambling Task. All participants were female, aged between 18 and 60 years and spoke Spanish as their first language. Results showed a negative correlation between 2-AG and cognitive flexibility performance (r = −.37; p<.05). A positive correlation was found between AEA concentrations and both cognitive flexibility (r = .59; p<.05) and decision making performance (r = .23; P<.05). There was no significant correlation between either 2-AG (r = −.17) or AEA (r = −.08) concentrations and inhibition response. These results show, in humans, a relevant modulation of the endocannabinoid system on prefrontal-dependent cognitive functioning. The present study might have significant implications for the underlying executive alterations described in some psychiatric disorders currently associated with endocannabinoids deregulation (namely drug abuse/dependence, depression, obesity and eating disorders). Understanding the neurobiology of their dysexecutive profile might certainly contribute to the development of new treatments and pharmacological approaches.  相似文献   
152.
153.
Rheumatoid arthritis (RA) is a complex polygenic inflammatory disease associated with accelerated atherosclerosis and increased risk of cardiovascular (CV) disease. Previous genome-wide association studies have described SMAD3 rs17228212 polymorphism as an important signal associated with CV events. The aim of the present study was to evaluate for the first time the relationship between this gene polymorphism and the susceptibility to CV manifestations and its potential association with the presence of subclinical atherosclerosis assessed by the evaluation of carotid intima-media thickness (cIMT) in patients with RA.

Methods

One thousand eight hundred and ninety-seven patients fulfilling classification criteria for RA were genotyped for SMAD3 rs17228212 gene polymorphism through TaqMan genotyping assay. Also, subclinical atherosclerosis determined by the assessment of cIMT was analyzed in a subgroup of these patients by carotid ultrasonography.

Results

No statistically significant differences were observed when allele frequencies of RA patients with or without CV events were compared. Nevertheless, when RA patients were stratified according to anti-cyclic citrullinated peptide (anti-CCP) status, we found that in RA patients who were negative for anti-CCP antibodies, the presence of C allele of SMAD3 rs17228212 polymorphism conferred a protective effect against the risk of cerebrovascular accident (CVA) after adjustment for demographic and classic CV risk factors (HR [95%CI]=0.36 [0.14–0.94], p=0.038) in a Cox regression model. Additionally, correlation between the presence of C allele of SMAD3 rs17228212 polymorphism and lower values of cIMT was found after adjustment for demographic and classic CV risk factors (p-value=0.0094) in the anti-CCP negative RA patients.

Conclusions

Our results revealed that SMAD3 rs17228212 gene variant is associated with lower risk of CVA and less severe subclinical atherosclerosis in RA patients negative for anti-CCP antibodies. These findings may have importance to establish predictive models of CV disease in RA patients according to anti-CCP status.  相似文献   
154.
155.

Background

For the first time in the history of HIV, new bio-medical interventions have been shown to be effective in preventing HIV transmission. For these new HIV prevention technologies (NPTs) to have an impact on the epidemic, they must be widely used. This study uses a discrete choice experiment (DCE) to: understand the relative strength of women’s preferences for product characteristics, understand the implications for substitution away from male condoms, and inform realistic modelling of their potential impact and cost-effectiveness.

Methods

A DCE was conducted among 1017 women in urban South Africa. Women were presented with choices between potential women’s NPTs (microbicides, diaphragm, female condom) and ‘what I did last time’ (use or not use a condom) with different HIV and pregnancy prevention effectiveness’ and prices. Choice probabilities are estimated using the nested logit model and used to predict uptake.

Results

In this high HIV prevalence setting, HIV prevention effectiveness is the main driver of uptake followed by pregnancy prevention effectiveness. For example a microbicide with poor effectiveness would have niche appeal at just 11% predicted uptake, while a highly effective microbicide (95% effective against HIV and pregnancy) would have far wider appeal (56% predicted uptake). Though women who reported not using condoms were more likely to choose the NPTs, at current very high rates of male condom use in South Africa (60%), about half of microbicide uptake is projected to be among those currently not using condoms.

Conclusions

Women are very interested in NPTs, especially if highly effective in preventing HIV and pregnancy. Women in greatest need were also most likely to switch to the new products. Where products are not yet available for distribution, proxy data, such as that generated by DCEs, can bring realism to overly optimistic uptake scenarios found in many current impact models.  相似文献   
156.
Cocaine dependence is a neuropsychiatric disorder in which both environmental and genetic factors are involved. Several processes, that include reward and neuroadaptations, mediate the transition from use to dependence. In this regard, dopamine and serotonin neurotransmission systems are clearly involved in reward and other cocaine‐related effects, whereas neurotrophic factors may be responsible for neuroadaptations associated with cocaine dependence. We examined the contribution to cocaine dependence of 37 genes related to the dopaminergic and serotoninergic systems, neurotrophic factors and their receptors through a case–control association study with 319 single nucleotide polymorphisms selected according to genetic coverage criteria in 432 cocaine‐dependent patients and 482 sex‐matched unrelated controls. Single marker analyses provided evidence for association of the serotonin receptor HTR2A with cocaine dependence [rs6561333; nominal P‐value adjusted for age = 1.9e?04, odds ratio = 1.72 (1.29–2.30)]. When patients were subdivided according to the presence or absence of psychotic symptoms, we confirmed the association between cocaine dependence and HTR2A in both subgroups of patients. Our data show additional evidence for the involvement of the serotoninergic system in the genetic susceptibility to cocaine dependence.  相似文献   
157.
Coumarin ( 1 ) and kaurane‐type diterpenes are considered the bioactive constituents of Mikania glomerata and M. laevigata, used in Brazil to treat respiratory affective disorders. The seasonal variation of 1 , ortho‐coumaric acid ( 2 ), benzoylgrandifloric acid ( 3 ), cinnamoylgrandifloric acid ( 4 ), and kaurenoic acid ( 5 ) in leaves of both species, cultivated in full sunlight and under shade levels of 40 and 80%, was quantified by HPLC. Compound 2 was detected solely in M. laevigata in concentrations below the limit of quantification. Coumarin was not found in M. glomerata, whereas its concentration reached 0.94±0.24% (w/w) in M. laevigata farmed in summer under 80% shading. Both Mikania species produced higher amounts of kaurane diterpenes when cultivated in plenty of sunlight. Hence, maximum contents of 1 are reached in M. laevigata cultivated under high shading, but with reduced concentrations of 3 – 5 . Conversely, M. glomerata should be cultivated under full sunlight and harvested in winter for highest concentrations of kaurane‐type diterpenes.  相似文献   
158.
The aim of the present study was to select strains of yeast with good enological qualities which were adapted to the ecological surroundings of Guijoso Appellation of Origin (A.O). For this, 11 white and red vats from different grape varieties and stages of fermentation were studied, making a total of 28 samples, with a selection of 370 isolated yeasts. Yeast cells of the Saccharomyces genus were analysed by DNA mitochondrial restriction for discrimination at the strain level, obtaining a total of 23 different molecular patterns. The pattern most frequently found was of G04, with 56 % of the isolated yeasts, followed by G02 with 15 % and G07 with 9 %. Other patterns found showed percentages close to 3 %, such as G01, G03, G05 and G06, while the remaining patterns were limited one or two isolated yeasts. Microfermentations at 25 and 15 °C were performed using a synthetic must, and the rate of fermentation, SH2 and foam production and the capacity to consume sugars from the medium were studied. Furthermore, the killer phenotype, flocculation capacity and phenolic off-flavour (POF) characteristics were also analysed. Natural musts from Chardonnay and Cabernet Sauvignon varieties were fermented using preselected strains and the wines obtained were analysed and tasted. Two strains were selected (G01 and G04) to be used as starters in Guijoso A.O.  相似文献   
159.

Background

The influence of new-onset atrial fibrillation (AF) on the long-term prognosis of nonagenarians who survive acute myocardial infarction (AMI) has not been demonstrated.

Objective

Our aim was to study the association between new-onset AF and long-term prognosis of nonagenarians who survive AMI.

Methods

From a total of 96 patients aged ≥89 years admitted during a 5-year period, 64 (67 %) were discharged alive and are the focus of this study.

Results

Mean age was 91.0 ± 2.0 years, and 39 patients (61 %) were women. During admission, 9 patients (14 %) presented new-onset AF, 51 (80 %) did not present AF, and 4 (6 %) had chronic AF. During follow-up (mean 2.3 ± 2.6 years; 6.6 ± 3.6 years in survivors), 58 patients (91 %) died, including the 9 patients with new-onset AF. Cumulative survival at 6, 12, 18, 24, and 30 months was 68.3 %, 57.2 %, 49.2 %, 47.6 %, and 31.8 %, respectively. The only two independent predictors of mortality in the multivariate analysis were age (hazard ratio [HR] 1.14; 95 % confidence interval [CI] 1.01–1.28; p = 0.04) and new-onset AF (HR 2.3; 95 % CI 1.1–4.8; p = 0.02).

Conclusion

New-onset AF is a marker of poor prognosis in nonagenarians who survive AMI.  相似文献   
160.
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