14 research outputs found

    Associations between Electronic Media Use and Involvement in Violence, Alcohol and Drug Use among United States High School Students

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    Objective: We identified associations between time spent watching television and time spent playing video or computer games or using computers and involvement in interpersonal violence, alcohol and drug use in a nationally representative sample of United States high school students. Methods: We analyzed data from the 2007 national Youth Risk Behavior Survey. Exposure variables were time spent watching television and time spent playing computer or video games or using computers (hereafter denoted as “computer/video game use”) on an average school day; outcome variables included multiple measures assessing involvement in violence and alcohol or drug use. Chi-square tests were used to identify statistically significant associations between each exposure variable and each of the outcome variables. We used logistic regression to obtain crude odds ratios for outcome variables with a significant chi-square p-value and to obtain adjusted odds ratios controlling for sex, race, and grade in school. Results: Overall, 35.4 % (95 % CI=33.1%-37.7%) of students reported frequent television (TV) use and 24.9 % (95 % CI=22.9%-27.0%) reported frequent computer/video game use. A number of risk behaviors, including involvement in physical fights and initiation of alcohol use before age 13, were significantly associated with frequent TV use or frequent computer/video game use, even afte

    Associations between Electronic Media Use and Involvement in Violence, Alcohol and Drug Use among United States High School Students

    Get PDF
    Objective: We identified associations between time spent watching television and time spent playing video or computer games or using computers and involvement in interpersonal violence, alcohol and drug use in a nationally representative sample of United States high school students. Methods: We analyzed data from the 2007 national Youth Risk Behavior Survey. Exposure variables were time spent watching television and time spent playing computer or video games or using computers (hereafter denoted as computer/video game use ) on an average school day; outcome variables included multiple measures assessing involvement in violence and alcohol or drug use. Chi-square tests were used to identify statistically significant associations between each exposure variable and each of the outcome variables. We used logistic regression to obtain crude odds ratios for outcome variables with a significant chi-square p-value and to obtain adjusted odds ratios controlling for sex, race, and grade in school. Results: Overall, 35.4% (95% CI=33.1%-37.7%) of students reported frequent television (TV) use and 24.9% (95% CI=22.9%-27.0%) reported frequent computer/video game use. A number of risk behaviors, including involvement in physical fights and initiation of alcohol use before age 13, were significantly associated with frequent TV use or frequent computer/video game use, even after controlling for sex, race/ethnicity and grade. Conclusion: Findings highlight the need for additional research to better understand the mechanisms by which electronic media exposure and health-risk behaviors are associated and for the development of strategies that seek to understand how the content and context (e.g., watching with peers, having computer in common area) of media use influence risk behaviors among youth

    Differentiation in Neuroblastoma: Diffusion-Limited Hypoxia Induces Neuro-Endocrine Secretory Protein 55 and Other Markers of a Chromaffin Phenotype

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    Background: Neuroblastoma is a childhood malignancy of sympathetic embryonal origin. A high potential for differentiation is a hallmark of neuroblastoma cells. We have previously presented data to suggest that in situ differentiation in tumors frequently proceeds along the chromaffin lineage and that decreased oxygen ( hypoxia) plays a role in this. Here we explore the utility of Neuro-Endocrine Secretory Protein 55 ( NESP55), a novel member of the chromogranin family, as a marker for this process.Methodology/Principal Findings: Immunohistochemical analyses and in situ hybridizations were performed on human fetal tissues, mouse xenografts of human neuroblastoma cell lines, and on specimens of human neuroblastoma/ganglioneuroma. Effects of anaerobic exposure on gene expression by cultured neuroblastoma cells was analyzed with quantitative real-time PCR. Fetal sympathetic nervous system expression of NESP55 was shown to be specific for chromaffin cell types. In experimental and clinical neuroblastoma NESP55 immunoreactivity was specific for regions of chronic hypoxia. NESP55 expression also correlated strikingly with morphological evidence of differentiation and with other chromaffin-specific patterns of gene expression, including IGF2 and HIF2 alpha. Anaerobic culture of five neuroblastoma cell lines resulted in an 18.9-fold mean up-regulation of NESP55.Conclusions/Significance: The data confirms that chronic tumor hypoxia is a key microenvironmental factor for neuroblastoma cell differentiation, causing induction of chromaffin features and NESP55 provides a reliable marker for this neuronal to neuroendocrine transition. The hypoxia-induced phenotype is the predominant form of differentiation in stroma-poor tumors, while in stroma-rich tumors the chromaffin phenotype coexists with ganglion cell-like differentiation. The findings provide new insights into the biological diversity which is a striking feature of this group of tumors
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