Adolescent girls' and parents' views on recruiting and retaining girls into an after-school dance intervention: implications for extra-curricular physical activity provision

<p>Abstract</p> <p>Background</p> <p>Many adolescents are not sufficiently active and girls are less active than boys. Physical activity interventions delivered during curriculum time have reported weak effects. More sustained changes in physical activity may be obtained by facilitating participation in enjoyable activities. Dance is the favourite activity of UK girls but there is a shortage of dance provision. Dance sessions delivered after the school day could prove to be an effective means of engaging adolescent girls in physical activity. There is a lack of information about the factors that would affect girls' recruitment and retention in an after-school dance programme.</p> <p>Methods</p> <p>Focus groups were conducted with 65, Year 7 (11-12 year old) girls from 4 secondary schools in Bristol. In-depth phone interviews were also conducted with 16 (4 per school) of the girls' parents. Interviews and focus groups examined issues that would affect recruitment into the intervention, strategies that could be used to attract girls who have little or no previous experience in dance, any factors that would increase their interest in participating in an after-school dance programme and any factors that would affect retention in the programme. All interviews and focus groups were digitally recorded and thematically analysed.</p> <p>Results</p> <p>Girls reported that a taster session in which they had an opportunity to sample the intervention content and "word of mouth" campaigns by peers, who did not need to be their friends, would encourage them to participate in an after-school dance programme. Sessions that maximised enjoyment and facilitated socialisation opportunities would enhance retention. Parents reported that encouraging groups of friends to join the programme, and stressing the enjoyment of the session would increase participation.</p> <p>Conclusions</p> <p>Recruitment and retention campaigns that focus on enjoyment, socialisation, mastery, goal setting and relating to other girls may be effective strategies for recruiting and retaining girls in an after-school dance programme. These factors are consistent with well-established theories of individual behaviour change such as self-determination theory and social cognitive theory. Recruitment and retention campaigns that are targeted to address theoretically derived mediators of behaviour may be more effective than traditional approaches.</p

Bristol Girls Dance Project Feasibility Trial: Outcome and process evaluation results

Background: Many adolescent girls do not engage in sufficient physical activity (PA). This study examined the feasibility of conducting a cluster randomized controlled trial (RCT) to evaluate an after-school dance program to increase PA among 11-12 year old girls in Bristol, UK.Methods: Three-arm, cluster RCT. Three secondary schools were assigned to intervention arm. Intervention participants received a 9-week dance program with 2, 90-minute dance classes per week. Participants at 2 control schools received incentives for data collection. Participants at 2 additional control schools received incentives and a delayed dance workshop. Accelerometer data were collected at baseline (time 0), during the last week of the dance program (time 1) and 20 weeks after the start of the study (time 2). Weekly attendance, enjoyment and perceived exertion were assessed in intervention participants. Post-study qualitative work was conducted with intervention participants and personnel.Results: 40.1% of girls provided consent to be in the study. The mean number of girls attending at least one dance session per week ranged from 15.4 to 25.9. There was greater number of participants for whom accelerometer data were collected in control arms. The mean attendance was 13.3 sessions (maximum = 18). Perceived exertion ratings indicated that the girls did not find the sessions challenging. The dance teachers reported that the program content would benefit from revisions including less creative task time, a broader range of dance genres and improved behavioral management policies. At time 2, the 95% confidence intervals suggest between 5 and 12 minutes more weekday MVPA in the intervention group compared with the control incentives only group, and between 6 minutes fewer and 1 minute more compared with the control incentives plus workshop group. Between 14 and 24 schools would be required to detect a difference of 10 minutes in mean weekday MVPA between intervention and control groups.Conclusions: It is possible to recruit 11-12 year old girls to participate in an after-school dance study. An after-school dance intervention has potential to positively affect the PA levels of 11-12 year old girls but an adequately powered RCT is required to test this intervention approach. © 2012 Jago et al.; licensee BioMed Central Ltd

Intrarectal transmission, systemic infection, and CD4+ T cell depletion in humanized mice infected with HIV-1

Intrarectal infection between men who have sex with men represents a predominant form of human immunodeficiency virus (HIV) transmission in developed countries. Currently there are no adequate small animal models that recapitulate intrarectal HIV transmission. Here we demonstrate that human lymphocytes generated in situ from hematopoietic stem cells reconstitute the gastrointestinal tract of humanized mice with human CD4+ T cells rendering them susceptible to intrarectal HIV transmission. HIV infection after a single intrarectal inoculation results in systemic infection with depletion of CD4+ T cells in gut-associated lymphoid tissue and other pathologic sequela that closely mimics those observed in HIV infected humans. This novel model provides the basis for the development and evaluation of novel approaches aimed at immune reconstitution of human gut-associated lymphoid tissue and for the development, testing, and implementation of microbicides to prevent intrarectal HIV-1 transmission

CD4+ T Cell Depletion during all Stages of HIV Disease Occurs Predominantly in the Gastrointestinal Tract

The mechanisms underlying CD4+ T cell depletion in human immunodeficiency virus (HIV) infection are not well understood. Comparative studies of lymphoid tissues, where the vast majority of T cells reside, and peripheral blood can potentially illuminate the pathogenesis of HIV-associated disease. Here, we studied the effect of HIV infection on the activation and depletion of defined subsets of CD4+ and CD8+ T cells in the blood, gastrointestinal (GI) tract, and lymph node (LN). We also measured HIV-specific T cell frequencies in LNs and blood, and LN collagen deposition to define architectural changes associated with chronic inflammation. The major findings to emerge are the following: the GI tract has the most substantial CD4+ T cell depletion at all stages of HIV disease; this depletion occurs preferentially within CCR5+ CD4+ T cells; HIV-associated immune activation results in abnormal accumulation of effector-type T cells within LNs; HIV-specific T cells in LNs do not account for all effector T cells; and T cell activation in LNs is associated with abnormal collagen deposition. Taken together, these findings define the nature and extent of CD4+ T cell depletion in lymphoid tissue and point to mechanisms of profound depletion of specific T cell subsets related to elimination of CCR5+ CD4+ T cell targets and disruption of T cell homeostasis that accompanies chronic immune activation

Macrophages sustain HIV replication in vivo independently of T cells

Macrophages have long been considered to contribute to HIV infection of the CNS; however, a recent study has contradicted this early work and suggests that myeloid cells are not an in vivo source of virus production. Here, we addressed the role of macrophages in HIV infection by first analyzing monocytes isolated from viremic patients and patients undergoing antiretroviral treatment. We were unable to find viral DNA or viral outgrowth in monocytes isolated from peripheral blood. To determine whether tissue macrophages are productively infected, we used 3 different but complementary humanized mouse models. Two of these models (bone marrow/liver/thymus [BLT] mice and T cell–only mice [ToM]) have been previously described, and the third model was generated by reconstituting immunodeficient mice with human CD34+ hematopoietic stem cells that were devoid of human T cells (myeloid-only mice [MoM]) to specifically evaluate HIV replication in this population. Using MoM, we demonstrated that macrophages can sustain HIV replication in the absence of T cells; HIV-infected macrophages are distributed in various tissues including the brain; replication-competent virus can be rescued ex vivo from infected macrophages; and infected macrophages can establish de novo infection. Together, these results demonstrate that macrophages represent a genuine target for HIV infection in vivo that can sustain and transmit infection

Location and Dynamics of the Immunodominant CD8 T Cell Response to SIVΔnef Immunization and SIVmac251 Vaginal Challenge

Live-attenuated SIV vaccines (LAVs) have been the most effective to date in preventing or partially controlling infection by wild-type SIV in non-human primate models of HIV-1 transmission to women acting by mechanisms of protection that are not well understood. To gain insights into mechanisms of protection by LAVs that could aid development of effective vaccines to prevent HIV-1 transmission to women, we used in situ tetramer staining to determine whether increased densities or changes in the local distribution of SIV-specific CD8 T cells correlated with the maturation of SIVΔnef vaccine-induced protection prior to and after intra-vaginal challenge with wild-type SIVmac251. We evaluated the immunodominant Mamu-A1*001:01/Gag (CM9) and Mamu-A1*001:01/Tat (SL8) epitope response in genital and lymphoid tissues, and found that tetramer+ cells were present at all time points examined. In the cervical vaginal tissues, most tetramer+ cells were distributed diffusely throughout the lamina propria or co-localized with other CD8 T cells within lymphoid aggregates. The distribution and densities of the tetramer+ cells at the portal of entry did not correlate with the maturation of protection or change after challenge. Given these findings, we discuss the possibility that changes in other aspects of the immune system, including the quality of the resident population of virus-specific effector CD8 T cells could contribute to maturation of protection, as well as the potential for vaccine strategies that further increase the size and quality of this effector population to prevent HIV-1 transmission

Live SIV vaccine correlate of protection: immune complex-inhibitory Fc receptor interactions that reduce target cell availability

Principles to guide design of an effective vaccine against HIV are greatly needed, particularly to protect women in the pandemic’s epicentre in Africa. We have been seeking these principles by identifying correlates of the robust protection associated with SIVmac239Δnef vaccination in the SIV-rhesus macaque animal model of HIV-1 transmission to women. We have identified one correlate of SIVmac239Δnef protection against vaginal challenge as a resident mucosal system for SIV-gp41 trimer antibody production and neonatal Fc receptor (FcRn)-mediated concentration of these antibodies on the path of virus entry to inhibit establishment of infected founder populations at the portal of entry. Here we identify as a second protection correlate, blocking CD4+ T cell recruitment to inhibit local expansion of infected founder populations. Virus-specific immune complex interactions with the inhibitory FcγRIIb receptor in the epithelium lining the cervix initiate expression of genes that block recruitment of target cells to fuel local expansion. Immune complex-FcγRIIb receptor interactions at mucosal frontlines to dampen the innate immune response to vaginal challenge could be a potentially general mechanism for the mucosal immune system to sense and modulate the response to a previously encountered pathogen. Designing vaccines to provide protection without eliciting these transmission-promoting innate responses could contribute to developing an effective HIV-1 vaccine

Live SIV vaccine correlate of protection: immune complex-inhibitory Fc receptor interactions that reduce target cell availability

Principles to guide design of an effective vaccine against HIV are greatly needed, particularly to protect women in the pandemic’s epicentre in Africa. We have been seeking these principles by identifying correlates of the robust protection associated with SIVmac239Δnef vaccination in the SIV-rhesus macaque animal model of HIV-1 transmission to women. We have identified one correlate of SIVmac239Δnef protection against vaginal challenge as a resident mucosal system for SIV-gp41 trimer antibody production and neonatal Fc receptor (FcRn)-mediated concentration of these antibodies on the path of virus entry to inhibit establishment of infected founder populations at the portal of entry. Here we identify as a second protection correlate, blocking CD4+ T cell recruitment to inhibit local expansion of infected founder populations. Virus-specific immune complex interactions with the inhibitory FcγRIIb receptor in the epithelium lining the cervix initiate expression of genes that block recruitment of target cells to fuel local expansion. Immune complex-FcγRIIb receptor interactions at mucosal frontlines to dampen the innate immune response to vaginal challenge could be a potentially general mechanism for the mucosal immune system to sense and modulate the response to a previously encountered pathogen. Designing vaccines to provide protection without eliciting these transmission-promoting innate responses could contribute to developing an effective HIV-1 vaccine

Glycerol monolaurate prevents mucosal SIV transmission

Although there has been great progress in treating human immunodeficiency virus 1 (HIV-1) infection1, preventing transmission has thus far proven an elusive goal. Indeed, recent trials of a candidate vaccine and microbicide have been disappointing, both for want of efficacy and concerns about increased rates of transmission2–4. Nonetheless, studies of vaginal transmission in the simian immunodeficiency virus (SIV)–rhesus macaque (Macacca mulatta) model point to opportunities at the earliest stages of infection in which a vaccine or microbicide might be protective, by limiting the expansion of infected founder populations at the portal of entry5,6. Here we show in this SIV–macaque model, that an outside-in endocervical mucosal signalling system, involving MIP-3α (also known as CCL20), plasmacytoid dendritic cells and CCR5+ cell-attracting chemokines produced by these cells, in combination with the innate immune and inflammatory responses to infection in both cervix and vagina, recruits CD4+ T cells to fuel this obligate expansion. We then show that glycerol monolaurate—a widely used antimicrobial compound7with inhibitory activity against the production of MIP-3α and other proinflammatory cytokines8—can inhibit mucosal signalling and the innate and inflammatory response to HIV-1 and SIV in vitro, and in vivo it can protect rhesus macaques from acute infection despite repeated intra-vaginal exposure to high doses of SIV. This new approach, plausibly linked to interfering with innate host responses that recruit the target cells necessary to establish systemic infection, opens a promising new avenue for the development of effective interventions to blockHIV-1 mucosal transmission