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31.

Background

While drinking alcohol, one must choose between the immediate rewarding effects and the delayed reward of a healthier lifestyle. Individuals differ in their devaluation of a delayed reward based on the time required to receive it, i.e., delay discounting (DD). Previous studies have shown that adolescents discount more steeply than adults and that steeper DD is associated with heavier alcohol use in both groups.

Methods

In a large-scale longitudinal study, we investigated whether higher rates of DD are an antecedent or a consequence of alcohol use during adolescent development. As part of the IMAGEN project, 2220 adolescents completed the Monetary Choice Questionnaire as a DD measure, the Alcohol Use Disorders Identification Test, and the Timeline Follow Back interview at ages 14, 16, 18, and 22. Bivariate latent growth curve models were applied to investigate the relationship between DD and drinking. To explore the consequences of drinking, we computed the cumulative alcohol consumption and correlated it with the development of discounting. A subsample of 221 participants completed an intertemporal choice task (iTeCh) during functional magnetic resonance imaging at ages 14, 16, and 18. Repeated-measures ANOVA was used to differentiate between high-risk and low-risk drinkers on the development of neural processing during intertemporal choices.

Results

Overall, high rates of DD at age 14 predicted a greater increase in drinking over 8 years. In contrast, on average, moderate alcohol use did not affect DD from ages 14 to 22. Of note, we found indicators for less brain activity in top-down control areas during intertemporal choices in the participants who drank more.

Conclusions

Steep DD was shown to be a predictor rather than a consequence of alcohol use in low-level drinking adolescents. Important considerations for future longitudinal studies are the sampling strategies to be used and the reliability of the assessments.
  相似文献   
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A maternal low protein (LP) diet in rodents often results in low nephron endowment and renal pathophysiology in adult life, with outcomes often differing between male and female offspring. Precisely how a maternal LP diet results in low nephron endowment is unknown. We conducted morphological and molecular studies of branching morphogenesis and nephrogenesis to identify mechanisms and timepoints that might give rise to low nephron endowment. Sprague–Dawley rats were fed a normal protein (19.4% protein, NP) or LP (9% protein) diet for 3 weeks prior to mating and throughout gestation. Embryonic day 14.25 (E14.25) kidneys from males and females were either cultured for 2 days after which branching morphogenesis was quantified, or frozen for gene expression analysis. Real-time PCR was used to quantify expression of key nephrogenesis and branching morphogenesis genes at E14.25 and 17.25. At E17.25, nephron number was determined in fixed tissue. There was no effect of either maternal diet or sex on branching morphogenesis. Nephron number at E17.25 was 14% lower in male and female LP offspring than in NP controls. At E14.25 expression levels of genes involved in branching morphogenesis (Gfrα1, Bmp4, Gdnf) and nephrogenesis (Hnf4a, Pax2, Wnt4) were similar in the dietary groups, but significant differences between sexes were identified. At E17.25, expression of Gfrα1, Gdnf, Bmp4, Pax2 and Six2 was lower in LP offspring than NP offspring, in both male and female offspring. These findings provide new insights into how a LP diet leads to low nephron endowment and renal sexual dimorphism.  相似文献   
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Background

The long-term effects of bariatric surgery have yet to be established, and a number of important studies have recently emerged. This systematic review aimed to assess the effects of bariatric surgery on all-cause mortality, cardiovascular events, and cancer compared to non-surgical treatment.

Methods

We searched PubMed, EMBASE, and CENTRAL up to July 13, 2015, and included randomized controlled trials (RCTs) and non-randomized controlled studies comparing bariatric surgery versus non-surgical treatment and reporting data on the three defined outcomes at 1 year or longer. We analyzed RCTs and non-randomized controlled studies, respectively.

Results

Eleven RCTs, 4 non-randomized controlled trials, and 17 cohort studies were included. The randomized evidence suggested substantial uncertainty regarding the effects on all-cause mortality (0/382 vs. 1/287; 7 studies), cancer (OR 0.77, 95 % CI 0.22 to 2.71; 4 studies), and cardiovascular events (no data). The pooled adjusted estimates from non-randomized studies suggested that, compared to the control, the surgical group had lower risk of all-cause mortality (OR 0.55, 95 % CI 0.46 to 0.65; 10 studies), cancer (OR 0.74, 95 % CI 0.65 to 0.85; 2 studies), and cardiovascular events (MI: OR 0.71, 95 % CI 0.54 to 0.94; stroke: OR 0.66, 95 % CI 0.49 to 0.89; and their composite: OR 0.67, 95 % CI 0.54 to 0.83; 1 study).

Conclusions

In conclusion, bariatric surgery could reduce all-cause mortality and probably reduce the risk of any type of cancer. The inference was, however, based on studies with limited methodological rigor. Uncertainty remains regarding the effects on cardiovascular events.
  相似文献   
39.
BACKGROUND/AIM: Trefoil factor family (TFF)1,2,3 are involved in a homeostasis/repair process of mucosal epithelia. In this study, the significance of TFF family and deleted in the malignant brain tumor-1 (DMBT1), a putative receptor of TFF2, in the intrahepatic biliary tree was investigated in normal and diseased livers. MATERIALS AND METHODS: Expression of TFF1,2,3 and DMBT1 were examined immunohistochemically in primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), chronic viral hepatitis (CVH), extrahepatic biliary obstruction (EBO), and normal livers. RESULTS: In normal livers, TFF1,3 and DMBT1 were infrequently detectable in large and rarely in small bile ducts, respectively. TFF2 was not detectable in large bile ducts. In large bile duct diseases (PSC and EBO), expression of TFF3 and DMBT1 were increased. In small bile duct diseases (PBC and CVH), expression of TFF2/DMBT1 was induced in moderately to severely damaged ducts irrespective of etiology. CONCLUSION: The intrahepatic biliary tree shows a site-characteristic expression and induction of TFF1,2,3 and DMBT1. In large bile ducts, TFF1,3 were constitutively expressed and increased in pathologic bile ducts. In small bile ducts, TFF2/DMBT1 is induced in damaged ducts irrespective of etiologies. However, the cytoprotective/repair property of TFF2/DMBT1 may not be enough to prevent the following bile duct loss in PBC.  相似文献   
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