164 research outputs found

    CHARACTERISTICS OF IMMUNOLOGICAL MEMORY IN MICE : I. SEPARATE EARLY GENERATION OF CELLS MEDIATING IGM AND IGG MEMORY TO SHEEP ERYTHROCYTES

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    The kinetics of the generation of primed IgM and IgG antibody-forming cell precursors, and of helper T-cell populations, were analyzed in mice whose primary responses to high and low doses of SRBC were arrested at intervals by the immunosuppressive agents cyclophosphamide monohydrate and specific antibody. The extent to which immunological memory was established in these animals before blockade of the primary response was assessed by the hemolytic plaque assay following challenge 12 wk after priming. The presence of IgG B-memory cells and T-memory cells in suppressed mice was further investigated by the transfer into these animals of syngeneic SRBC-stimulated thymocytes or anti-Ξ-treated spleen cells. It was found that the progenitors of secondary IgM-synthesizing cells were primed almost immediately after injection of antigen, and that early blockade of the primary response resulted in a raised IgM response after challenge. On the other hand, priming for a secondary IgG response took at least 4 days, and was dose-dependent, although helper T populations for a secondary IgG response appeared 3 days after antigen injection. It appeared that both IgM and IgG memory cells may be considered as Y cells in terms of the X-Y-Z scheme of lymphocyte activation, but that the two populations are generated at different times after exposure to antigen. The size of either Y-cell population at any given time is dependent upon the amount of antigen available to provoke differentiation to antibody-forming Z cells, and the IgM Y-cell population in particular is likely to be depleted during the course of a normal 1° response. When IgM Y cells were maintained for long periods as a result of immunosuppression, their secondary antibody response was independent of the primed T cells necessary for a secondary IgG response

    Which game narratives do adolescents of different gameplay and sociodemographic backgrounds prefer? a mixed-methods analysis

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    OBJECTIVE: The aim of this study was to investigate which narrative elements of digital game narratives are preferred by the general adolescent population, and to examine associations with gender, socioeconomic status (SES), and gameplay frequency. Further, the study aims to discuss how results can be translated to serious digital games. MATERIALS AND METHODS: Adolescents were recruited through school to complete a survey on narrative preferences in digital games. The survey included questions on sociodemographic information, frequency of gameplay, and an open-ended question on what could be an appealing narrative for them. Data were analyzed in a mixed-methods approach, using thematic analysis and chi-square analyses to determine narrative preferences and the associations between game narrative elements and player characteristics (gender, SES, and frequency of gameplay). RESULTS: The sample consisted of 446 adolescents (12-15 years old) who described 30 narrative subthemes. Preferences included human characters as protagonists; nonhuman characters only as antagonists; realistic settings, such as public places or cities; and a strong conflict surrounding crime, catastrophe, or war. Girls more often than boys defined characters by their age, included avatars, located the narrative in private places, developed profession-related skills, and included a positive atmosphere. Adolescents of nonacademic education more often than adolescents of academic education defined characters by criminal actions. Infrequent players more often included human characters defined by their age than frequent players. After performing a Bonferroni correction, narrative preferences for several gender differences remained. CONCLUSION: Different narrative elements related to subgroups of adolescents by gender, SES, and frequency of gameplay. Customization of narratives in serious digital health games should be warranted for boys and girls; yet, further research is needed to specify how to address girls in particular

    Inequalities in health complaints: 20-year trends among adolescents in Scotland, 1998–2018

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    This study examined trends in inequalities in health complaints among early adolescents in Scotland from 1998 to 2018. We analysed data from the Health Behaviour in School-aged Children (HBSC) survey conducted in Scotland in 1998, 2002, 2006, 2010, 2014 and 2018. A self-report questionnaire was administered in schools to a nationally representative sample of 11-, 13-, and 15-year-olds (n = 29,250). Health complaints were measured using a scale comprising four psychological symptoms (feeling low, feeling nervous, irritability and sleep difficulties) and four somatic symptoms (headache, backache, stomachache and dizziness). Socio-economic status was measured using the Family Affluence Scale. Between 1998 and 2018, there were significant increases in the proportion of girls and boys reporting feeling low, feeling nervous, sleep difficulties and backache. Prevalence of the eight individual health complaints was higher among girls and adolescents from lower affluence families. Socio-economic inequalities increased over time, such that declines in mental health were greatest among low affluence adolescents. The data show worsening trends in health complaints among Scottish adolescents between 1998 and 2018, particularly for girls and adolescents from low affluence families. Increasing inequalities in mental health highlight the need to address the underlying social and structural determinants of adolescent mental health

    Association of alcohol control policies with adolescent alcohol consumption and with social inequality in adolescent alcohol consumption : a multilevel study in 33 countries and regions

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    Funding: The Health Behaviour in School-aged Children (HBSC) is an international study carried out in collaboration with WHO Europe. This research is funded by public sources in each member country. Specifically, ELL, CMM, and ISQ are supported by the Ministry de Health, Spain. CMM is supported by the VI Plan Propiode InvestigaciĂłn de la Universidad de Sevilla 2018, under the action “II.5B Contrato de acceso al Sistema Españolde Ciencia, TecnologĂ­a e InnovaciĂłn para el Desarrollo del Programa Propio de I + D + i de la Universidad de Sevilla”. JI is supported by the UK Medical Research Council (MC_UU_12017/12) and the Chief Scientist Office (SPHSU12).Background  Previous research found inconsistent associations between alcohol control policies and socioeconomic inequality with adolescent drinking outcomes. This study expands the focus beyond individual associations to examine whether a combination of policies is related to socioeconomic inequality in adolescent drinking outcomes and whether this relationship varies across survey years. Methods  Multilevel modelling of 4 waves of repeat cross-sectional survey data (2001/02, 2005/06, 2009/10, and 2013/14) from the Health Behaviour in School-aged Children (HBSC) study was carried out. The sample was composed of 671,084 adolescents (51% girls) aged 11, 13, and 15 (mean age=13.58; SD=1.65) from 33 European and North American countries/regions. The dependent variables were lifetime alcohol consumption, weekly alcohol consumption, and lifetime drunkenness. Independent variables were of three types: individual-level variables (age, sex, Family Affluence Scale, and the Perceived Family Wealth), time-level variable (survey year), and context-level variables (minimum legal drinking age, physical availability, advertising restrictions, a total alcohol policy index, and affordability of alcohol). Results  The total alcohol policy index showed a negative relationship with both lifetime and weekly consumption. Higher affordability of alcohol was related to higher lifetime and weekly consumption and higher lifetime drunkenness. Family Affluence Scale was positively related to all three alcohol measures and Perceived Family Wealth was negatively related to lifetime drunkenness, with these associations increasing across survey years. The total alcohol policy index buffered the associations of Family Affluence Scale and Perceived Family Wealth with adolescent drinking outcomes. Conclusion  A combination of alcohol control policies is more effective in reducing adolescent drinking outcomes than single policy measures. Reducing the affordability of alcohol stood out as the most successful single measure. Socioeconomic inequalities (i.e. higher alcohol consumption and drunkenness in adolescents with higher family affluence and higher drunkenness in adolescents perceiving their families to be poor) have persisted and even increased across survey years. A combined alcohol control policy can help in tackling them.PostprintPublisher PDFPeer reviewe

    Do social support and eating family meals together play a role in promoting resilience to bullying and cyberbullying in Scottish school children?

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    Funding for the Scottish 2018 HBSC Survey was provided by NHS Health Scotland. This work was also supported by the MRC Mental Health Data Pathfinder Award (reference MC_PC_17217).This study investigates if cyberbullying is associated with wellbeing independently of traditional bullying and if social support and eating family meals together promotes resilience by buffering adolescents against the consequences of both types of bullying. Data for 5286 eleven, thirteen and fifteen year olds participating in the cross-sectional 2018 Scottish Health Behaviour in School-aged Children study were analysed. Adolescent self-report measures were used to assess traditional bullying, cyberbullying, classmate and teacher support and frequency of family meals together. Psychological wellbeing was assessed with the 5-item World Health Organization Wellbeing index. Analyses were conducted separately by gender with multilevel models, adjusting for sociodemographic factors. Resilience to bullying and cyberbullying was operationalised using statistical interactions. For both genders, cyberbullying and traditional bullying measures were associated with reduced wellbeing and all social support indicators were associated with increased wellbeing. In models containing both bullying measures, frequent traditional bullying victimisation was associated with a 7.2 (95% CI: 3.4–10.1) reduction in wellbeing score for boys and a 7.2 (95% CI: 4.5–10.0) reduction for girls, while cyberbullying was associated with 10.5 (95% CI: 5.8–15.1) reduction in wellbeing score for boys and 11.1 (95% CI: 6.7–15.5) reduction for girls. For both genders adjusting for classmate support explained away the relationships between traditional bullying and wellbeing, but cyberbullying was associated negatively with wellbeing independent of social support. Only one of 12 interaction tests provided any evidence of resilience. Cyberbullying was associated with a 7.8 (95% CI: 0.2–15.4) reduction in wellbeing score for girls who ate with their family every day, and 17.3 (95% CI: 10.5–24.1) reduction for girls who ate with their families less than weekly. In conclusion, cyberbullying is a strong, albeit rare, threat to adolescent wellbeing. Social support is important for wellbeing, but its ability to buffer adolescents against the consequences of bullying may be limited.Publisher PDFPeer reviewe

    Assessing the psychometric and ecometric properties of neighborhood scales using adolescent survey data from urban and rural Scotland

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    This work was supported by NHS Health Scotland and the University of St Andrews.Background:  Despite the well-established need for specific measurement instruments to examine the relationship between neighborhood conditions and adolescent well-being outcomes, few studies have developed scales to measure features of the neighborhoods in which adolescents reside. Moreover, measures of neighborhood features may be operationalised differently by adolescents living in different levels of urban/rurality. This has not been addressed in previous studies. The objectives of this study were to: 1) establish instruments to measure adolescent neighborhood features at both the individual and neighborhood level, 2) assess their psychometric and ecometric properties, 3) test for invariance by urban/rurality, and 4) generate neighborhood level scores for use in further analysis. Methods:  Data were from the Scottish 2010 Health Behaviour in School-aged Children Survey, which included an over-sample of rural adolescents. The survey responses of interest came from questions designed to capture different facets of the local area in which each respondent resided. Intermediate data zones were used as proxies for neighborhoods. Internal consistency was evaluated by Cronbach’s alpha. Invariance was examined using confirmatory factor analysis. Multilevel models were used to estimate ecometric properties and generate neighborhood scores. Results:  Two constructs labeled neighborhood social cohesion and neighborhood disorder were identified. Adjustment was made to the originally specified model to improve model fit and measures of invariance. At the individual level, reliability was .760 for social cohesion and .765 for disorder, and between .524 and .571 for both constructs at the neighborhood level. Individuals in rural areas experienced greater neighborhood social cohesion and lower levels of neighborhood disorder compared with those in urban areas. Conclusions:  The scales are appropriate for measuring neighborhood characteristics experienced by adolescents across urban and rural Scotland, and can be used in future studies of neighborhoods and health. However, trade-offs between neighborhood sample size and reliability must be considered.Publisher PDFPeer reviewe

    Accelerometry-assessed sleep duration and timing in late childhood and adolescence in Scottish schoolchildren: a feasibility study

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    Children and adolescents commonly suffer from sleep and circadian rhythm disturbances, which may contribute to poorer mental health and wellbeing during this critical developmental phase. Many studies however rely on self-reported sleep measures. This study assessed whether accelerometry data collection was feasible within the school setting as a method for investigating the extent of sleep and circadian disruption, and associations with subjective wellbeing, in Scotland. Fourteen days of wrist-worn accelerometry data were collected from 69 pupils, aged 10–14 years. Objective measures of sleep timing, sleep duration and circadian rest-activity patterns were derived. Questionnaires assessed subjective sleep timing, depressive symptoms, and experiences of wearing the accelerometer. Pupils slept on average less than 8 hours per night, failing to meet standard age-specific recommendations. Sleep timing was later and duration longer on weekends compared to weekdays (B = 0.87, 95% confidence interval (CI) 0.70, 1.04; B = 0.49, 95% CI 0.29, 0.69), indicating social jetlag. Lower daytime activity was correlated with higher depressive symptoms (r = -0.84, p = 0.008). Compared to primary school pupils, secondary pupils had shorter sleep window duration and lower circadian relative amplitude. Over half of participants reported some discomfort/inconvenience wearing the accelerometer. These data highlight that inadequate sleep is prevalent in this sample of schoolchildren. Future, larger scale investigations will examine in more detail the associations between sleep, circadian function and physical activity with mental health and wellbeing

    Trends in the perceived body size of adolescent males and females in Scotland, 1990–2014: changing associations with mental well-being

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    Objectives: This paper explores trends in Scottish adolescents’ body size perceptions and associated mental well-being outcomes. Methods: Data were collected on Scottish 11, 13 and 15-year olds by the Health Behaviour in School-aged Children study between 1990 and 2014 (n=42,312). Logistic regression was used to examine changes in the prevalence of over- and underweight perceptions. Ordinal and linear regression was used to examine changes in the association between body perception and mental well-being. Results: Little change was observed in over- or under-weight perceptions between 1990 and 2014. However, relative to those perceiving their body as ‘about right’, those perceiving themselves as overweight reported decreasing confidence (all groups), decreasing happiness (11- and 13-year old girls) and increasing psychological symptoms (all girls and 15 year-old boys). Perceived underweight is associated with poor well-being, especially in males, but we present little evidence that this is a recent phenomenon. Conclusions: We present evidence suggesting that the influence of body image on adolescent mental health is increasing over time. This may play a role in the recently observed worsening of mental well-being in Scottish adolescents.Publisher PDFPeer reviewe

    Lessons learned from the AFLY5 RCT process evaluation: Implications for the design of physical activity and nutrition interventions in schools Health behavior, health promotion and society

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    © 2015 Jago et al. Background: Systematic reviews have highlighted that school-based diet and physical activity (PA) interventions have had limited effects. This study used qualitative methods to examine how the effectiveness of future primary (elementary) school diet and PA interventions could be improved. Methods: Data are from the Active For Life Year 5 (AFLY5) study, which was a cluster randomised trial conducted in 60 UK primary schools. Year 5 (8-9 years of age) pupils in the 30 intervention schools received a 12-month intervention. At the end of the intervention period, interviews were conducted with: 28 Year 5 teachers (including 8 teachers from control schools); 10 Headteachers (6 control); 31 parents (15 control). Focus groups were conducted with 70 year 5 pupils (34 control). Topics included how the AFLY5 intervention could have been improved and how school-based diet and PA interventions should optimally be delivered. All interviews and focus groups were transcribed and thematically analysed across participant groups. Results: Analysis yielded four themes. Child engagement: Data suggested that programme success is likely to be enhanced if children feel that they have a sense of autonomy over their own behaviour and if the activities are practical. School: Finding a project champion within the school would enhance intervention effectiveness. Embedding diet and physical activity content across the curriculum and encouraging teachers to role model good diet and physical activity behaviours were seen as important. Parents and community: Encouraging parents and community members into the school was deemed likely to enhance the connection between schools, families and communities, and "create a buzz" that was likely to enhance behaviour change. Government/Policy: Data suggested that there was a need to adequately resource health promotion activity in schools and to increase the infrastructure to facilitate diet and physical activity knowledge and practice. Discussion and Conclusions: Future primary school diet and PA programmes should find ways to increase child engagement in the programme content, identify programme champions, encourage teachers to work as role models, engage parents and embed diet and PA behaviour change across the curriculum. However, this will require adequate funding and cost-effectiveness will need to be established. Trial registration: ISRCTN5013374
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