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Environmental deprivation contributes in important ways to the development of a wide range of psychiatric disorders. Isolation rearing of rodents, a model for environmental deprivation in humans, consistently produces hyperlocomotion, which provides a measurable parameter to study the underlying mechanisms of early adverse psychosocial stressors. Male Sprague-Dawley rat pups were separated from dams at postnatal (PN) day 20 and reared either in groups of three or in isolation. On PN 38, locomotion was assessed in the open field. On PN 46, rats were killed and gene expression patterns examined in the medial prefrontal cortex (mPFC). Isolation-reared rats displayed increased locomotor activity and decreased resting time in the open field. Specific gene expression patterns in the mPFC were associated with both isolation rearing and hyperlocomotive behavior in the open field. Genes involved in these expression patterns included immediate early genes (IEGs) and genes that regulate cell differentiation and apoptosis. The study of these genes could provide important insights into how abnormal early psychosocial events affect brain function and behavior.  相似文献   
84.
OBJECTIVE: The goal of this study was to evaluate peer-related influences on appearance, body dissatisfaction, eating disturbance, and self-esteem in average weight, at risk of overweight, and overweight adolescent girls. METHODS: Three hundred twenty-five adolescent girls from high schools in Florida were assessed. Ninety met criteria for being at risk of overweight or overweight. Logistic and multiple regression analyses were used to evaluate group differences on all variables and to assess the amount of variance accounted for by peer-influence variables in the prediction of body dissatisfaction, eating disturbance, and self-esteem. RESULTS: Overweight and at risk of overweight girls scored higher than average weight girls on body dissatisfaction, dieting, and a peer measure that assessed negative comments and attributions about appearance. They also scored lower than average weight girls on self-report measures that assessed conversations about appearance and anti-dieting advice. How influential friends were in determining one's body image was a unique predictor of body dissatisfaction but only for the overweight and at risk of overweight group. CONCLUSIONS: Possible implications for clinical intervention programs are discussed along with directions for future research.  相似文献   
85.
As has been repeatedly demonstrated, alcohol can exert deleterious morphological and physiological effects during early stages in development. The present review examines nonteratological links existing between alcohol and ontogeny. Human and animal studies are taken into consideration for the analysis of fetal, neonatal, infantile, adolescent, and adult responsiveness to the drug. Sensitivity to alcohol's chemosensory and postabsorptive properties, as well as learning and memory processes mediated by such properties, are examined from this developmental perspective. The studies under discussion indicate that, within each stage in development, we can trace alcohol-related experiences capable of determining or modulating alcohol seeking and intake patterns.  相似文献   
86.

Background

Micronutrient deficiency is a global health burden, especially among developing countries. The present cross‐sectional study aimed to determine the prevalence of vitamin B12 deficiency in healthy Indian school‐going adolescents, based on area of residence, sex and body mass index (BMI) . Furthermore, the relationship of serum B12 concentration with dietary vitamin B12 intake and anthropometric indices was assessed among adolescents from rural and urban India.

Methods

A total of 2403 school‐going adolescents (11–17 years) from National Capital Region and rural areas of Haryana, India were selected. Serum B12 concentrations were estimated using an electrochemiluminescence immunoassay. Dietary assessments were conducted on 65% of total participants (n  = 1556) by two 24‐h diet recalls.

Results

The prevalence of vitamin B12 deficiency in the total study population was 32.4% (rural: 43.9% versus urban: 30.1%, P  < 0.001; male: 34.4% versus female: 31.0%, P  < 0.05; normal weight: 28.1%, versus overweight: 39.8%, versus obese: 51.2%, P  < 0.001). More than half (51.2%) of obese adolescents were vitamin B12 deficient. On multiple linear regression analysis, serum B12 in rural adolescents was associated with age (β = ?0.12, P  < 0.05). Among urban adolescents, serum B12 was associated with BMI (β = ?0.08, P  < 0.05) and adjusted dietary vitamin B12 intake (β = 0.14, P  < 0.001). Serum vitamin B12 levels were found to be lower in rural females (β = ?0.12, P  = 0.030) and urban males (β: 0.11, P  < 0.001) compared to their respective contemporaries.

Conclusions

Vitamin B12 deficiency was higher among rural school‐going adolescents. Boys had a higher B12 deficiency than girls. Inverse associations of serum B12 with adiposity indices were observed. Serum B12 levels were positively associated with dietary vitamin B12 intake.
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87.
Objective: To assess gender differences in the relationship between eating and weight loss attitudes (EWAs), and 30-day tobacco and alcohol use among adolescents, while controlling for potential confounds (age, country of birth, psychological distress, pubertal development, peer alcohol and tobacco use, and sexual activity). Methods: School students aged between 11 and 17 years (N = 10,273) from high schools in the State of Victoria (Australia) completed surveys in class under conditions of anonymity and confidentiality. Results: The interaction between EWAs and gender was significant for tobacco use but not for alcohol use, indicating that the effect of EWAs on tobacco use, but not alcohol use, vary by gender. Conclusions: Tobacco use was related to EWAs in adolescent females but not males, and this is consistent with the possibility that females use tobacco in an instrumental fashion to control weight. Implications and Contribution: Female adolescents high in eating and weight loss attitudes were more likely to engage in tobacco use. In contrast, eating and weight loss attitudes were not related to male tobacco use. These results point to the potential importance of developing gender-specific approaches towards addressing problematic behaviors in adolescent populations.  相似文献   
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Background and PurposeMany young people consume ecstasy as a recreational drug and often in combination with cannabis. In this study, we aimed to mimic human consumption patterns and investigated, in male and female animals, the long-term effects of Δ9-tetrahydrocannabinol (THC) and 3,4-methylenedioxymethamphetamine (MDMA) on diverse neuroinflammation and neurotoxic markers.Experimental ApproachMale and female Wistar rats were chronically treated with increasing doses of THC and/or MDMA during adolescence. The effects of THC and/or MDMA on glial reactivity and on serotoninergic and cannabinoid systems were assessed by immunohistochemistry in the hippocampus and parietal cortex.Key ResultsTHC increased the area staining for glial fibrilar acidic protein in both sexes. In males, both drugs, either separately or in combination, increased the proportion of reactive microglia cells [ionized calcium binding adaptor molecule 1 (Iba-1)]. In contrast, in females, each drug, administered alone, decreased of this proportion, whereas the combination of both drugs resulted in a ‘normalization’ to control values. In males, MDMA reduced the number of SERT positive fibres, THC induced the opposite effect and the group receiving both drugs did not significantly differ from the controls. In females, MDMA reduced the number of SERT positive fibres and the combination of both drugs counteracted this effect. THC also reduced immunostaining for CB1 receptors in females and this effect was aggravated by the combination with MDMA.Conclusions and ImplicationsAdolescent exposure of rats to THC and/or MDMA induced long-term, sex-dependent neurochemical and glial alterations, and revealed interactions between the two drugs.Linked ArticlesThis article is part of a themed section on Cannabinoids 2013. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-6  相似文献   
90.
This study investigates how changes in alcohol use-specific parenting were associated with adolescent drinking trajectories. Three waves of data from a longitudinal study investigating adolescent substance use were used. The community sample (N = 378) was aged 10–13 at the first wave of assessment. Our findings show that over time, parents are less likely to discipline their adolescents' drinking, more likely to grant their adolescent permission to drink, and less likely to communicate the consequences of alcohol use. Moreover, these changes are associated with escalation in adolescent alcohol use. Parental efficacy at preventing alcohol use declined, but did not relate to changes in adolescent drinking.  相似文献   
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