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《Neuropsychopharmacology》2019,85(11):956-965
BackgroundBinge eating and other forms of disordered eating behavior (DEB) are associated with failed inhibitory control. This study investigated the neural correlates of failed inhibitory control as a potential biomarker for DEB.MethodsThe study used prospective longitudinal data from the European IMAGEN study adolescent cohort. Participants completed baseline assessments (questionnaires and a brain scan [functional magnetic resonance imaging]) at 14 years of age and a follow-up assessment (questionnaires) at 16 years of age. Self-reported binge eating and/or purging were used to indicate presence of DEB. Neural correlates of failed inhibition were assessed using the stop signal task. Participants were categorized as healthy control subjects (reported no DEB at both time points), maintainers (reported DEB at both time points), recoverers (reported DEB at baseline only), and developers (reported DEB at follow-up only). Forty-three individuals per group with complete scanning data were matched on gender, age, puberty, and intelligence (N = 172).ResultsAt baseline, despite similar task performance, incorrectly responding to stop signals (failed inhibitory control) was associated with greater recruitment of the medial prefrontal cortex and anterior cingulate cortex in the developers compared with healthy control subjects and recoverers.ConclusionsGreater recruitment of the medial prefrontal and anterior cingulate regions during failed inhibition accords with abnormal evaluation of errors contributing to DEB development. As this precedes symptom onset and is evident despite normal task performance, neural responses during failed inhibition may be a useful biomarker of vulnerability for DEB. This study highlights the potential value of prospective neuroimaging studies for identifying markers of illness before the emergence of behavior changes.  相似文献   
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目的了解上海市浦东新区小学生超重肥胖的现状以及学生的营养知识、态度和饮食行为,为开展学生营养知识宣传与相关行为干预提供依据。方法按照分层整群随机抽样的方法,抽取浦东新区6 824名小学生测量身高和体重;随机整群抽取1 122名小学生和家长进行有关的问卷调查,剔除不合格问卷,获得有效问卷1 089份,有效率为97.1%。结果浦东新区小学生超重和肥胖检出率分别为22.0%和10.7%,总超重率为32.7%,其中男生超重、肥胖检出率为24.5%和13.2%,总超重肥胖率为37.8%,女生超重、肥胖检出率为19.0%和7.7%,总超重率为26.7%,男生超重率高于女生,差异有统计学意义(χ~2=30.111,P0.01),男生肥胖率高于女生,差异有统计学意义(χ~2=55.004,P0.01)。全体学生的营养知识水平偏低,平均得分为(4.68±1.166)分,学生对合理膳食的基本要求、钙元素和维生素C的良好来源等知识掌握比较好,但对于相对专业的营养知识掌握较差。学生对零食、饮料的食用频率较高,1周吃8~14次分别达到10.1%和10.6%,豆类食用频率相对较少。结论上海市浦东新区小学生超重及肥胖检出率已超过全国平均水平,小学生整体的营养知识水平不高,零食、饮料和油炸烧烤等食品食用频率较高。针对这些问题,应结合当地的实际情况积极采取各项措施,培养科学合理的饮食行为。  相似文献   
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Purpose

To quantify eating disorder (ED) stability and diagnostic transition among a community-based sample of adolescents and young adult females in the United States.

Methods

Using 11 prospective assessments from 9,031 U.S. females ages 9–15 years at baseline of the Growing Up Today Study, we classified cases of the following EDs involving bingeing and purging: bulimia nervosa (BN), binge ED, purging disorder (PD), and subthreshold variants defined by less frequent (monthly vs. weekly) bingeing and purging behaviors. We measured number of years symptomatic and probability of maintaining symptoms, crossing to another diagnosis, or resolving symptoms across consecutive surveys.

Results

Study lifetime disorder prevalence was 2.1% for BN and roughly 6% each for binge ED and PD. Most cases reported symptoms during only one survey year. Twenty-six percent of cases crossed between diagnoses during follow-up. Among participants meeting full threshold diagnostic criteria, transition from BN was most prevalent, crossing most frequently from BN to PD (12.9% of BN cases). Within each disorder phenotype, 20%–40% of cases moved between subthreshold and full threshold criteria across consecutive surveys.

Conclusions

Diagnostic crossover is not rare among adolescent and young adult females with an ED. Transition patterns from BN to PD add support for considering these classifications in the same diagnostic category of disorders that involve purging. The prevalence of crossover between monthly and weekly symptom frequency suggests that a continuum or staging approach may increase utility of ED classification for prognostic and therapeutic intervention.  相似文献   
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