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Problem: Unhealthy dietary behaviors, physical inactivity, and tobacco use contribute to chronic disease and other health conditions, including obesity, diabetes, and asthma. These behaviors often are established during childhood and adolescence, extend into adulthood, are interrelated, and are preventable.Reporting Period Covered: January--May 2005.Description of System: The Youth Risk Behavior Surveillance System (YRBSS) monitors priority health-risk behaviors, general health status, and the prevalence of overweight and asthma among youth and young adults. YRBSS includes a national school-based survey conducted by CDC and state and local school-based surveys conducted by state and local education and health agencies.As a component of YRBSS, in 2005, communities participating in the Steps to a HealthierUS Cooperative Agreement Program (Steps Program) also conducted school-based surveys of students in grades 9--12 in their program intervention areas. These communities used a modified core questionnaire that asks about dietary behaviors, physical activity, and tobacco use and monitors the prevalence of overweight, diabetes, and asthma. This report summarizes results from surveys of students in 15 Steps communities that conducted surveys in 2005.Results: Results from the 15 Steps communities indicated that a substantial proportion of adolescents engaged in health risk behaviors associated with obesity, diabetes, and asthma. During 2005, across surveys, the percentage of high school students who had not eaten fruits and vegetables >5 times/day during the 7 days preceding the survey ranged from 80.1% to 85.2% (median: 83.1%), the percentage who were overweight ranged from 6.6% to 19.6% (median: 11.5%), the percentage who did not attend physical education classes daily ranged from 53.7% to 95.1% (median: 74.2%), and the percentage who had smoked cigarettes during the 30 days preceding the survey ranged from 9.2% to 26.5% (median: 17.1%).Interpretation: Although the prevalence of many health-risk behaviors and health conditions varies across Steps communities, a substantial proportion of high school students engage in behaviors that place them at risk for chronic disease.Public Health Action: Steps Program staff at the national, tribal, state, and local levels will use YRBSS data for decision making, program planning, and enhancing technical assistance. These data will be used to focus existing programs on activities with the greatest promise of results, identify opportunities for strategic collaboration, and identify and disseminate lessons learned. [ABSTRACT FROM AUTHOR]

In the United States, 71% of all deaths among persons aged 10-24 years result from 4 causes: motorvehicle crashes, other unintentional injuries, homicide, and suicide. Results from the 2005 national Youth Risk Behavior Survey (YRBS) indicated that during the 30 days preceding the survey, many high school students engaged in behaviors that increased their likelihood of death from these 4 causes: 9.9% had driven a car or other vehicle when they had been drinking alcohol, 18.5% had carried a weapon, 43.3% had drunk alcohol, and 20.2% had used marijuana. In addition, during the 12 months preceding the survey, 35.9% of high school students had been in a physical fight and 8.4% had attempted suicide. Substantial morbidity and social problems among youth also result from unintended pregnancies and sexually transmitted diseases, including human immunodeficiency virus infection. During 2005, a total of 46.8% of high school students had ever had sexual intercourse, 37.2% of sexually active high school students had not used a condom at last sexual intercourse, and 2.1% had ever injected an illegal drug. Among adults aged >=25 years, 61% of all deaths result from 2 causes: cardiovascular disease and cancer. Results from the 2005 national YRBS indicated that risk behaviors associated with these 2 causes of death were initiated during adolescence. During 2005, a total of 23.0% of high school students had smoked cigarettes during the 30 days preceding the survey, 79.9% had not eaten >=5 times/day of fruits and vegetables during the 7 days preceding the survey, 67.0% did not attend physical education classes daily, and 13.1% were overweight. [ABSTRACT FROM AUTHOR]

Problem/Condition: Priority health-risk behaviors, which contribute to the leading causes of morbidity and mortality among youth and adults, often are established during youth, extend into adulthood, are interrelated, and are prevent-able. Reporting Period: This report covers data collected during February-December 2003. Description of System: The Youth Risk Behavior Surveillance System (YRBSS) monitors six categories of priority health-risk behaviors among youth and young adults - behaviors that contribute to unintentional injuries and vio-lence; tobacco use; alcohol and other drug use; sexual behaviors that contribute to unintended pregnancy and sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV) infection; unhealthy dietary behaviors; and physical inactivity - plus overweight. YRBSS includes a national school-based survey conducted by CDC as well as state and local school-based surveys conducted by education and health agencies. This report summarizes results from the national survey, 32 state surveys, and 18 local surveys conducted among students in grades 9-12 during February-December 2003. Results and Interpretation: In the United States, 70.8% of all deaths among persons aged 10-24 years result from only four causes: motor-vehicle crashes, other unintentional injuries, homicide, and suicide. Results from the 2003 national Youth Risk Behavior Survey demonstrated that, during the 30 days preceding the survey, numerous high school students engage in behaviors that increase their likelihood of death from these four causes: 30.2% had ridden with a driver who had been drinking alcohol; 17.1% had carried a weapon; 44.9% had drunk alcohol; and 22.4% had used marijuana. In addition, during the 12 months preceding the survey, 33.0% of high school students had been in a physical fight, and 8.5% had attempted suicide. Substantial morbidity and social problems among young persons also result from unintended pregnancies and STDs, including HIV infection. In 2003, 46.7% of high school students had ever had sexual intercourse; 37% of sexually active students had not used a condom at last sexual intercourse; and 3.2% had ever injected an illegal drug. Among adults aged >25 years, 62.9% of all deaths results from two causes: cardiovas-cular diseases and cancer. Results from the 2003 national Youth Risk Behavior Survey demonstrate that the majority of risk behaviors associated with these two causes of death are initiated during adolescence. In 2003, a total of 21.9% of high school students had smoked cigarettes during the 30 days preceding the survey; 78% had not eaten >5 servings/ day of fruits and vegetables during the 7 days preceding the survey; 33.4% had participated in an insufficient amount of physical activity; and 13.5% were overweight. Actions Taken: YRBSS data are being used to measure progress toward achieving 15 national health objectives for 2010 and three of the 10 leading health indicators. In addition, education and health officials at national, state, and local levels are using these YRBSS data to improve policies and programs to reduce priority health-risk behaviors among youth. [ABSTRACT FROM AUTHOR]

Priority health risk behaviors that contribute to the leading causes of mortality, morbidity, and social problems among youth and adults often are established during youth, extend into adulthood, and are interrelated. The Youth Risk Behavior Surveillance System (YRBSS) monitors six categories of priority health risk behaviors among youth and youth adults: behaviors that contribute to unintentional and intentional injuries, tobacco use, alcohol and other drug use, sexual behaviors, dietary behaviors, and physical activity. The YRBSS includes a national, school-based survey conducted by CDC and state and local school-based surveys conducted by state and local education agencies. This report summarizes results from the national survey, 24 state surveys, and nine local surveys conducted among high school students during February through May 1993. In the United States, 72% of all deaths among school-age youth and young adults are from four causes: motor vehicle crashes, other intentional injuries, homicide, and suicide. Results from the 1993 YRBSS suggest many high school students practice behaviors that may increase their likelihood of death from these four causes: 191% rarely or never use a safety belt, 35.3% had ridden during the 30 days preceding the survey with a driver who had been drinking alcohol, 22.1% had carried a weapon during the 30 days preceding the survey, 80.9% ever drank alcohol, 32 8% ever used marijuana, and 8.6% had attempted suicide during the 12 months preceding the survey. Substantial morbidity and social problems among adolescents also result from unintended pregnancies and sexually transmitted diseases including HIV infection. YRBSS results indicate that in 1993, 53% of high school students had experienced sexual intercourse, 52.8% of sexually active students had used a condom during last sexual intercourse, and 1.4% ever injected an illegal drug. Among adults, 67% of all deaths are from three causes: heart disease, cancer, and stroke. In 1993, many high school students practiced behaviors that may increase the risk for these health problems. 30.5% of high school students had smoked cigarettes during the 30 days preceding the survey, only 15.4% had eaten five or more servings of fruits and vegetables during the day preceding the survey, and only 34.3% had attended physical education class daily. YRBSS data are being used nationwide by health and education officials to improve school health policies and programs designed to reduce risks associated with the leading causes of mortality and morbidity. At the national level, YRBSS data are being used to measure progress toward achieving 26 national health objectives and one of eight National Education Coals. [ABSTRACT FROM AUTHOR]

The Youth Risk Behavior Surveillance System (YRBSS) is a set of surveys that tracks a broad range of behaviors, experiences, and conditions that can lead to poor health among high school students. The system includes a nationally representative Youth Risk Behavior Survey (YRBS) and separate school-based YRBSs conducted by states, tribes, territories, and local school districts. For the 2023 national YRBS, CDC made changes to the sampling method, survey administration mode, and questionnaire. Specifically, the sampling design added an American Indian or Alaska Native (AI/AN) supplemental sample so that separate, precise estimates could be made for AI/AN high school students, in addition to the usual sample designed to provide nationally representative data for the population of students in grades 9-12. To decrease the time needed to collect and process data, CDC changed the survey administration mode from paper-and-pencil scannable booklets to a tablet-based electronic survey. To provide national data on topics of emerging interest, CDC added new questions to the questionnaire. These new questions assessed social media use, experiences of racism at school, adverse childhood experiences, transgender identity, consent for sexual contact, and unfair discipline at school. Public health practitioners and researchers can use YRBSS data to examine the prevalence of youth health behaviors, experiences, and conditions; monitor trends; and guide interventions. This overview report describes 2023 YRBSS survey methodology, including sampling, data collection, data processing, weighting, and data analyses. The 2023 YRBS participation map, survey response rates, and a detailed examination of student demographic characteristics are included in this report. During 2023, in addition to the national YRBS, 68 site-level surveys were administered to high school students in 39 states, three tribal governments, five territories, and 21 local school districts. These site-level surveys use site-specific questionnaires that are similar to the national YRBS questionnaire but are modified to meet sites' needs. This overview and methods report is one of 11 featured in this MMWR supplement, which reports results from the 2023 national YRBS but does not include data from the 68 site-level surveys. Each report is based on data collected using methods presented in this overview report. A full description of YRBSS results and downloadable data are available (https://www.cdc.gov/yrbs/index.html)., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Jonetta Mpofu reported being a board member of the American School Health Association. Lindsay Trujillo reported receiving a grant from Social & Scientific Systems, Inc. No other potential conflicts of interest were disclosed.

Purpose: The Youth Risk Behavior Survey (YRBS) monitors behaviors, experiences, and conditions affecting the health of high school students nationwide. This study examined the test-retest reliability of the 2021 national YRBS questionnaire., Design: Respondents completed a Time 1 and Time 2 paper-and-pencil questionnaire approximately 2 weeks apart during February to May 2022. Data were linked in such a way as to preserve anonymity., Setting: Convenience sample of high schools., Subjects: High school students (N = 588)., Measures: Health risk behaviors and experiences assessed on the 2021 national YRBS questionnaire., Analysis: Time 1 and Time 2 responses were compared for each questionnaire item using the McNemar's test. Then, Cohen's kappa coefficients tested the agreement between Time 1 and Time 2 responses overall, and by sex, grade, and Black, White, and Hispanic race and ethnicity., Results: Among the 74 items analyzed, 96% had at least moderate reliability, and 73% had substantial or almost perfect reliability. The mean Cohen's kappa was .68. McNemar's test findings showed Time 1 and Time 2 data significantly differed ( P < .01) for 9 items (12%)., Conclusion: Reliable health behavior measures are important in the development of youth-focused public health programs and policies. Findings suggest the national YRBS questionnaire is a reliable instrument. Such findings lend support to relying on adolescent self-reported data when monitoring health behaviors using the YRBS., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The Youth Risk Behavior Surveillance System (YRBSS) is the largest public health surveillance system in the United States, monitoring a broad range of health-related behaviors among high school students. The system includes a nationally representative Youth Risk Behavior Survey (YRBS) and separate school-based YRBSs conducted by states, tribes, territories, and local school districts. In 2021, these surveys were conducted during the COVID-19 pandemic. The pandemic underscored the importance of data in understanding changes in youth risk behaviors and addressing the multifaceted public health needs of youths. This overview report describes 2021 YRBSS survey methodology, including sampling, data collection procedures, response rates, data processing, weighting, and analyses. The 2021 YRBS participation map, survey response rates, and a detailed examination of student demographic characteristics are included in this report. During 2021, in addition to the national YRBS, a total of 78 surveys were administered to high school students across the United States, representing the national population, 45 states, two tribal governments, three territories, and 28 local school districts. YRBSS data from 2021 provided the first opportunity since the onset of the COVID-19 pandemic to compare youth health behaviors using long-term public health surveillance. Approximately half of all student respondents represented racial and ethnic minority groups, and approximately one in four identified as lesbian, gay, bisexual, questioning, or other (a sexual identity other than heterosexual) (LGBQ+). These findings reflect shifts in youth demographics, with increased percentages of racial and ethnic minority and LGBQ+ youths compared with previous YRBSS cycles. Educators, parents, local decision makers, and other partners use YRBSS data to monitor health behavior trends, guide school health programs, and develop local and state policy. These and future data can be used in developing health equity strategies to address long-term disparities so that all youths can thrive in safe and supportive environments. This overview and methods report is one of 11 featured in this MMWR supplement. Each report is based on data collected using methods presented in this overview. A full description of YRBSS results and downloadable data are available (https://www.cdc.gov/healthyyouth/data/yrbs/index.htm)., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

Many U.S. schools closed nationwide in March 2020 to prevent the spread of COVID-19. School closures and online-only instruction have negatively affected certain students, with studies showing adverse effects of the pandemic on mental health. However, little is known about other experiences such as economic and food insecurity and abuse by a parent, as well as risk behaviors such as alcohol and drug use among youths across the United States during the pandemic. To address this gap, CDC developed the one-time, online Adolescent Behaviors and Experiences Survey (ABES), which was conducted during January-June 2021 to assess student behaviors and experiences during the COVID-19 pandemic among high school students, including unintentional injury, violence, tobacco product use, sexual behaviors, and dietary behaviors. This overview report of the ABES MMWR Supplement describes the ABES methodology, including the student questionnaire and administration, sampling, data collection, weighting, and analysis. ABES used a stratified, three-stage cluster probability-based sampling approach to obtain a nationally representative sample of students in grades 9-12 attending public and private schools. Teachers of selected classes provided students with access to the anonymous online survey while following local consent procedures. Data were collected using a 110-item questionnaire during January-June 2021 in 128 schools. A total of 7,998 students submitted surveys, and 7,705 of these surveys had valid data (i.e., ≥20 questions answered). The school response rate was 38%, the student response rate was 48%, and the overall response rate was 18%. Information on mode of instruction and school-provided equipment was also collected from all sampled schools. This overview report provides student- and school-level characteristics obtained from descriptive analyses, and the other reports in the ABES MMWR Supplement include information on substance use, mental health and suicidality, perceived racism, and disruptions to student life among high school students. Findings from ABES during the COVID-19 pandemic can help guide parents, teachers, school administrators, community leaders, clinicians, and public health officials in decision-making for student support and school health programs., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

An important question in early neural development is the origin of stochastic nuclear movement between apical and basal surfaces of neuroepithelia during interkinetic nuclear migration. Tracking of nuclear subpopulations has shown evidence of diffusion - mean squared displacements growing linearly in time - and suggested crowding from cell division at the apical surface drives basalward motion. Yet, this hypothesis has not yet been tested, and the forces involved not quantified. We employ long-term, rapid light-sheet and two-photon imaging of early zebrafish retinogenesis to track entire populations of nuclei within the tissue. The time-varying concentration profiles show clear evidence of crowding as nuclei reach close-packing and are quantitatively described by a nonlinear diffusion model. Considerations of nuclear motion constrained inside the enveloping cell membrane show that concentration-dependent stochastic forces inside cells, compatible in magnitude to those found in cytoskeletal transport, can explain the observed magnitude of the diffusion constant., Competing Interests: AA, AH, YW, SB, PK, WH No competing interests declared, RG Reviewing editor, eLife, (© 2020, Azizi et al.)

Health risk behaviors practiced during adolescence often persist into adulthood and contribute to the leading causes of morbidity and mortality in the United States. Youth health behavior data at the national, state, territorial, tribal, and local levels help monitor the effectiveness of public health interventions designed to promote adolescent health. The Youth Risk Behavior Surveillance System (YRBSS) is the largest public health surveillance system in the United States, monitoring a broad range of health-related behaviors among high school students. YRBSS includes a nationally representative Youth Risk Behavior Survey (YRBS) and separate state, local school district, territorial, and tribal school-based YRBSs. This overview report describes the surveillance system and the 2019 survey methodology, including sampling, data collection procedures, response rates, data processing, weighting, and analyses presented in this MMWR Supplement. A 2019 YRBS participation map, survey response rates, and student demographic characteristics are included. In 2019, a total of 78 YRBSs were administered to high school student populations across the United States (national and 44 states, 28 local school districts, three territories, and two tribal governments), the greatest number of participating sites with representative data since the surveillance system was established in 1991. The nine reports in this MMWR Supplement are based on national YRBS data collected during August 2018-June 2019. A full description of 2019 YRBS results and downloadable data are available (https://www.cdc.gov/healthyyouth/data/yrbs/index.htm).Efforts to improve YRBSS and related data are ongoing and include updating reliability testing for the national questionnaire, transitioning to electronic survey administration (e.g., pilot testing for a tablet platform), and exploring innovative analytic methods to stratify data by school-level socioeconomic status and geographic location. Stakeholders and public health practitioners can use YRBS data (comparable across national, state, tribal, territorial, and local jurisdictions) to estimate the prevalence of health-related behaviors among different student groups, identify student risk behaviors, monitor health behavior trends, guide public health interventions, and track progress toward national health objectives., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

Background: Plant-associated microbiomes, which are shaped by host and environmental factors, support their hosts by providing nutrients and attenuating abiotic and biotic stresses. Although host genetic factors involved in plant growth and immunity are known to shape compositions of microbial communities, the effects of host evolution on microbial communities are not well understood., Results: We show evidence that both host speciation and domestication shape seed bacterial and fungal community structures. Genome types of rice contributed to compositional variations of both communities, showing a significant phylosymbiosis with microbial composition. Following the domestication, abundance inequality of bacterial and fungal communities also commonly increased. However, composition of bacterial community was relatively conserved, whereas fungal membership was dramatically changed. These domestication effects were further corroborated when analyzed by a random forest model. With these changes, hub taxa of inter-kingdom networks were also shifted from fungi to bacteria by domestication. Furthermore, maternal inheritance of microbiota was revealed as a major path of microbial transmission across generations., Conclusions: Our findings show that evolutionary processes stochastically affect overall composition of microbial communities, whereas dramatic changes in environments during domestication contribute to assembly of microbiotas in deterministic ways in rice seed. This study further provides new insights on host evolution and microbiome, the starting point of the holobiome of plants, microbial communities, and surrounding environments.

Ribosome assembly occurs mainly in the nucleolus, yet recent studies have revealed robust enrichment and translation of mRNAs encoding many ribosomal proteins (RPs) in axons, far away from neuronal cell bodies. Here, we report a physical and functional interaction between locally synthesized RPs and ribosomes in the axon. We show that axonal RP translation is regulated through a sequence motif, CUIC, that forms an RNA-loop structure in the region immediately upstream of the initiation codon. Using imaging and subcellular proteomics techniques, we show that RPs synthesized in axons join axonal ribosomes in a nucleolus-independent fashion. Inhibition of axonal CUIC-regulated RP translation decreases local translation activity and reduces axon branching in the developing brain, revealing the physiological relevance of axonal RP synthesis in vivo. These results suggest that axonal translation supplies cytoplasmic RPs to maintain/modify local ribosomal function far from the nucleolus in neurons., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Extrinsic cues trigger the local translation of specific mRNAs in growing axons via cell surface receptors. The coupling of ribosomes to receptors has been proposed as a mechanism linking signals to local translation but it is not known how broadly this mechanism operates, nor whether it can selectively regulate mRNA translation. We report that receptor-ribosome coupling is employed by multiple guidance cue receptors and this interaction is mRNA-dependent. We find that different receptors associate with distinct sets of mRNAs and RNA-binding proteins. Cue stimulation of growing Xenopus retinal ganglion cell axons induces rapid dissociation of ribosomes from receptors and the selective translation of receptor-specific mRNAs. Further, we show that receptor-ribosome dissociation and cue-induced selective translation are inhibited by co-exposure to translation-repressive cues, suggesting a novel mode of signal integration. Our findings reveal receptor-specific interactomes and suggest a generalizable model for cue-selective control of the local proteome., Competing Interests: MK, RC, TS, LW, PV, JQ, SZ, MJ, AD, MM, AB, CK, WH, JF, CH No competing interests declared, (© 2019, Koppers et al.)

Cell shape is critical for the proper function of every cell in every tissue in the body. This is especially true for the highly morphologically diverse neural and glia cells of the central nervous system. The molecular processes by which these, or indeed any, cells gain their particular cell-specific morphology remain largely unexplored. To identify the genes involved in the morphogenesis of the principal glial cell type in the vertebrate retina, the Müller glia (MG), we used genomic and CRISPR based strategies in zebrafish (Danio rerio). We identified 41 genes involved in various aspects of MG cell morphogenesis and revealed a striking concordance between the sequential steps of anatomical feature addition and the expression of cohorts of functionally related genes that regulate these steps. We noted that the many of the genes preferentially expressed in zebrafish MG showed conservation in glia across species suggesting evolutionarily conserved glial developmental pathways., (© 2019 The Authors. Glia published by Wiley Periodicals, Inc.)

Local translation regulates the axonal proteome, playing an important role in neuronal wiring and axon maintenance. How axonal mRNAs are localized to specific subcellular sites for translation, however, is not understood. Here we report that RNA granules associate with endosomes along the axons of retinal ganglion cells. RNA-bearing Rab7a late endosomes also associate with ribosomes, and real-time translation imaging reveals that they are sites of local protein synthesis. We show that RNA-bearing late endosomes often pause on mitochondria and that mRNAs encoding proteins for mitochondrial function are translated on Rab7a endosomes. Disruption of Rab7a function with Rab7a mutants, including those associated with Charcot-Marie-Tooth type 2B neuropathy, markedly decreases axonal protein synthesis, impairs mitochondrial function, and compromises axonal viability. Our findings thus reveal that late endosomes interact with RNA granules, translation machinery, and mitochondria and suggest that they serve as sites for regulating the supply of nascent pro-survival proteins in axons., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

The reaggregation of dissociated cells to form organotypic structures provides an in vitro system for the analysis of the cellular interactions and molecular mechanisms involved in the formation of tissue architecture. The retina, an outgrowth of the forebrain, is a precisely layered neural tissue, yet the mechanisms underlying layer formation are largely unexplored. Here we describe the protocol to dissociate, re-aggregate, and culture zebrafish retinal cells from a transgenic, Spectrum of Fates, line where all main cell types are labelled with a combination of fluorescent proteins driven by fate-specific promoters. These cells re-aggregate and self-organize in just 48 h in minimal culture conditions. We also describe how the patterning in these aggregates can be analyzed using isocontour profiling to compare whether different conditions affect their self-organization.