32 research outputs found
Insulin Degrading Enzyme Induces a Conformational Change in Varicella-Zoster Virus gE, and Enhances Virus Infectivity and Stability
Varicella-zoster virus (VZV) glycoprotein E (gE) is essential for virus infectivity and binds to a cellular receptor, insulin-degrading enzyme (IDE), through its unique amino terminal extracellular domain. Previous work has shown IDE plays an important role in VZV infection and virus cell-to-cell spread, which is the sole route for VZV spread in vitro. Here we report that a recombinant soluble IDE (rIDE) enhances VZV infectivity at an early step of infection associated with an increase in virus internalization, and increases cell-to-cell spread. VZV mutants lacking the IDE binding domain of gE were impaired for syncytia formation and membrane fusion. Pre-treatment of cell-free VZV with rIDE markedly enhanced the stability of the virus over a range of conditions. rIDE interacted with gE to elicit a conformational change in gE and rendered it more susceptible to proteolysis. Co-incubation of rIDE with gE modified the size of gE. We propose that the conformational change in gE elicited by IDE enhances infectivity and stability of the virus and leads to increased fusogenicity during VZV infection. The ability of rIDE to enhance infectivity of cell-free VZV over a wide range of incubation times and temperatures suggests that rIDE may be useful for increasing the stability of varicella or zoster vaccines
Mycobacterium tuberculosis epitope-specific interferon-g production in healthy Brazilians reactive and non-reactive to tuberculin skin test
The interferon (IFN)-gamma response to peptides can be a useful diagnostic marker of Mycobacterium tuberculosis (MTB) latent infection. We identified promiscuous and potentially protective CD4(+) T-cell epitopes from the most conserved regions of MTB antigenic proteins by scanning the MTB antigenic proteins GroEL2, phosphate-binding protein 1 precursor and 19 kDa antigen with the TEPITOPE algorithm. Seven peptide sequences predicted to bind to multiple human leukocyte antigen (HLA)-DR molecules were synthesised and tested with IFN-gamma enzyme-linked immunospot (ELISPOT) assays using peripheral blood mononuclear cells (PBMCs) from 16 Mantoux tuberculin skin test (TST)-positive and 16 TST-negative healthy donors. Eighty-eight percent of TST-positive donors responded to at least one of the peptides, compared to 25% of TST-negative donors. Each individual peptide induced IFN-gamma production by PBMCs from at least 31% of the TST-positive donors. the magnitude of the response against all peptides was 182 +/- 230 x 10(6) IFN-gamma spot forming cells (SFC) among TST-positive donors and 36 +/- 62 x 10(6) SFC among TST-negative donors (p = 0.007). the response to GroEL2 (463-477) was only observed in the TST-positive group. This combination of novel MTB CD4 T-cell epitopes should be tested in a larger cohort of individuals with latent tuberculosis (TB) to evaluate its potential to diagnose latent TB and it may be included in ELISPOT-based IFN-gamma assays to identify individuals with this condition.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Fac Med, Inst Coracao, Immunol Lab, São Paulo, BrazilUniversidade Federal de São Paulo, Fac Med, Dept Med, Div Imunol Clin & Alergia, São Paulo, BrazilFundacao Oswaldo Cruz, Lab Avancado Saude Publ, Salvador, BA, BrazilEscola Bahiana Med & Saude Publ, Salvador, BA, BrazilInst Invest Immunol, São Paulo, BrazilUniversidade Federal de São Paulo, Fac Med, Inst Coracao, Immunol Lab, São Paulo, BrazilUniversidade Federal de São Paulo, Fac Med, Dept Med, Div Imunol Clin & Alergia, São Paulo, BrazilWeb of Scienc
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Recruitment and retention in randomized controlled trials with urban American Indian/Alaska Native adolescents: Challenges and lessons learned.
BACKGROUND: Although the majority of American Indians/Alaska Natives reside in urban areas, there are very few randomized controlled trials analyzing culturally centered substance use prevention interventions for this population. METHODS: We describe methods employed to recruit and retain urban American Indian/Alaska Native adolescents into a randomized controlled trial, which was focused on testing the potential benefits of a substance use prevention intervention for this population. We also report challenges encountered in recruitment and retention of participants and strategies employed addressing these challenges. Data collection occurred from August 2014 to October 2017. RESULTS: We partnered with two community-based organizations in different cities in California. We utilized American Indian/Alaska Native recruiters from communities, placed flyers in community-based organizations, and asked organizations to post flyers on their web and social media sites. We also offered gift cards for participants. Our initial recruitment and retention model was moderately successful; however, we encountered five main challenges: (1) transportation, (2) increasing trust and interest, (3) adding research sites, (4) getting the word out about the project, and (5) getting youth to complete follow-up surveys. Strategies employed to overcome transportation challenges included shortening the number of sessions, offering sessions on both weekends and weekdays, and increasing bus tokens and transportation options. We hired more staff from American Indian/Alaska Native communities, added more research sites from our previously established relationships, and were more proactive in getting the word out on the project in American Indian/Alaska Native communities. We also utilized more field tracking and emailed and mailed survey invitations to reach more participants for their follow-up surveys. Because of our efforts, we were nearly able to reach our initial recruitment and retention goals. CONCLUSION: Although our research team had previously established relationships with various urban American Indian/Alaska Native communities, we encountered various recruitment and retention challenges in our study. However, by identifying challenges and employing culturally appropriate strategies, we were able to collect valuable data on the potential effectiveness of a substance use prevention intervention for urban American Indian/Alaska Native adolescents. Findings from this study assist toward the development of potentially successful strategies to successfully recruit and retain urban American Indian/Alaska Native adolescents in randomized controlled trials
Understanding sleep facilitators, barriers, and cultural dimensions in Native American urban youth.
OBJECTIVES: American Indian/Alaska Native (AI/AN) youth are a high-risk group for sleep problems and associated chronic conditions. Urban AI/AN youth may face certain challenges, including specific psychosocial stressors (e.g., discrimination) and environmental factors (e.g., noise, light) that render them particularly vulnerable to poor sleep health. However, few studies have explored AI/AN adolescent sleep. To our knowledge, this is the first study to use systematic qualitative methods with AI/AN youth to explore their sleep environment and sleep behaviors. DESIGN: In-depth interviews with 26 youth. SETTING: Two urban areas in Central and Southern California. PARTICIPANTS: Urban-dwelling AI/AN youth, age 12-16 years. INTERVENTION: N/A. MEASUREMENT: N/A. RESULTS: We identified five main themes, each with subthemes: sleep patterns and desired sleep, sleep barriers inside the home, environmental factors, sleep facilitators, and cultural dimensions. Key concerns discussed were poor sleep hygiene, excessive use of electronics prior to bedtime, issues with temperature regulation, and noise both within and outside the home. Parents can be an important vehicle for messaging around sleep health and for behavior management. Participating adolescents also indicated differing levels of attachment to Native identity, suggesting that culturally-targeted sleep interventions should build in openness and flexibility to a range of identity starting points. Further, we identified cultural practices, such as sweat lodges and dreamcatchers, that could be incorporated in future sleep interventions for this population. CONCLUSION: Findings increase our understanding of urban AI/AN youths sleep environments and behaviors, thus potentially informing program development around sleep health for this vulnerable population
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Overt Perceived Discrimination and Racial Microaggressions and their Association with Health Risk Behaviors among a Sample of Urban American Indian/Alaska Native Adolescents.
BACKGROUND: Urban American Indian/Alaska Native (AI/AN) adolescents are an understudied population in the USA who are at risk for a variety of health problems. Perceived discrimination (PD), including both overt PD and racial microaggressions (RMA), is known to adversely affect health. However, studies analyzing associations between overt PD and RMA and various health behaviors are limited. METHODS: This study measured past-year alcohol use, heavy drinking, marijuana use, commercialized tobacco use, consequences experienced from alcohol and marijuana use in the past 3 months, mental and physical health status, AI/AN traditional activity participation, and overt PD and RMA among 182 urban AI/AN adolescents in California. To assess the association between overt PD and RMAs and health outcomes, we conducted either logistic regression (for dichotomous outcomes: past-year alcohol use, past-year heavy drinking, past-year marijuana use, consequences of alcohol and marijuana use, commercialized tobacco use) or linear regression (for continuous outcomes: mental and physical health, AI/AN traditional practices). RESULTS: In contrast to our hypotheses, overt PD and RMA were not significantly associated with substance use or mental or physical health among this sample of urban AI/AN adolescents. After adjusting for age and gender, overt PD and RMA were only correlated with past-year cigarette use and alcohol-related consequences experienced in the past 3 months. CONCLUSION: Potential factors that may play a role in decreasing effects of overt PD and RMA among urban AI/AN adolescents are discussed, including participation in AI/AN traditional practices and community engagement
Unveiling an invisible population: health, substance use, sexual behavior, culture, and discrimination among urban American Indian/Alaska Native adolescents in California.
Objectives: There are limited public health data on urban American Indian/Alaska Native (AI/AN) populations, particularly adolescents. The current study attempted to address gaps by providing descriptive information on experiences of urban AI/AN adolescents across northern, central, and southern California.Design: We describe demographics and several behavioral health and cultural domains, including: alcohol and other drug (AOD) use, risky sexual behavior, mental and physical health, discrimination experiences, involvement in traditional practices, and cultural pride and belonging. We recruited 185 urban AI/AN adolescents across northern, central, and southern California from 2014 to 2017 who completed a baseline survey as part of a randomized controlled intervention trial.Results: Average age was 15.6 years; 51% female; 59% of adolescents that indicated AI/AN descent also endorsed another race or ethnicity. Rates of AOD use in this urban AI/AN sample were similar to rates for Monitoring the Future. About one-third of adolescents reported ever having sexual intercourse, with 15% reporting using alcohol or drugs before sex. Most reported good mental and physical health. Most urban AI/AN adolescents participated in traditional practices, such as attending Pow Wows and learning their tribal history. Adolescents also reported discrimination experiences, including being a victim of racial slurs and discrimination by law enforcement.Conclusions: This study describes a select sample of California urban AI/AN adolescents across several behavioral health and cultural domains. Although these adolescents reported numerous discrimination experiences and other stressors, findings suggest that this sample of urban AI/AN teens may be particularly resilient with regard to behavioral health
Mental Health, Physical Health, and Cultural Characteristics Among American Indians/Alaska Natives Seeking Substance Use Treatment in an Urban Setting: A Descriptive Study.
Although approximately 70% of American Indians/Alaska Natives (AI/ANs) reside in urban areas, our knowledge of risk and protective factors among AI/ANs seeking substance use treatment within urban areas is limited. We analyze substance and commercialized cigarette use, AI/AN cultural identity and involvement, physical health and cognitive functioning, and mental health symptoms among 63 AI/AN adults seeking substance use treatment within an urban area in California. Alcohol (37%), marijuana (27%), and methamphetamine (22%) were the most commonly reported substances. Sixty-two percent used commercialized tobacco use. The majority of AI/AN adults (78%) engaged in at least one traditional practice during the past month and endorsed high levels of spiritual connectedness. Those who engaged in traditional practices demonstrated significantly less depression (p = 0.007) and anxiety (p = 0.04). Medical and mental health issues were not prominent, although participants revealed high levels of cognitive impairment. Results highlight the importance of utilizing AI/AN traditional practices for AI/AN adults seeking substance use treatment within urban areas. Clinical Trials Registry Number NCT01356667
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Mixed Methods Evaluation of Satisfaction with Two Culturally Tailored Substance use Prevention Programs for American Indian/Alaska Native Emerging Adults.
American Indian/Alaska Native (AI/AN) communities are disproportionately affected by the opioid epidemic. AI/AN emerging adults (ages 18-25) in urban areas are at particularly high risk, with the overdose death rate among urban-dwelling AI/AN people 1.4 times higher than rural-dwelling AI/AN people. Despite these challenges, there are no evidence-based culturally tailored prevention or intervention programs to address opioid, alcohol and other drug use among urban AI/AN emerging adults. This study focused on understanding AI/AN emerging adults experiences with two culturally tailored programs addressing opioid, cannabis, and alcohol use as part of the randomized controlled trial for Traditions and Connections for Urban Native Americans (TACUNA) in order to enhance feasibility of this intervention. Using a convergent mixed methods design at 3-month follow-up, we collected satisfaction and experience ratings and written narratives (total n = 162; intervention n = 77; control n = 85) from a sample of urban-dwelling AI/AN emerging adults who participated in both programs. We analyzed data through simultaneous examination of qualitative and quantitative data. The quantitative ratings show that both programs were rated highly. The qualitative data contextualized these ratings, illustrating pathways through which specific components were perceived to cause desired or observed behavioral change in participants. Among the elements that mattered most to these participants were the convenience of the virtual format, having a comfortable and safe space to share personal stories, and learning new information about their social networks. Negative comments focused on workshop length and inconvenient scheduling. This is one of the first studies to explore participant satisfaction and experience with culturally tailored substance use programming among a historically marginalized and understudied population. It is important to consider the voices of urban-dwelling AI/AN people in program development because hidden factors, such as limited financial resources, limited time, and misalignment with cultural values may prevent existing programs from being feasible
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Identifying as American Indian/Alaska Native in Urban Areas: Implications for Adolescent Behavioral Health and Well-Being.
American Indian and Alaska Native (AI/AN) youth exhibit multiple health disparities, including high rates of alcohol and other drug (AOD) use, violence and delinquency, and mental health problems. Approximately 70% of AI/AN youth reside in urban areas, where negative outcomes on behavioral health and well-being are often high. Identity development may be particularly complex in urban settings, where youth may face more fragmented and lower density AI/AN communities, as well as mixed racial-ethnic ancestry and decreased familiarity with AI/AN lifeways. This study examines racial-ethnic and cultural identity among AI/AN adolescents and associations with behavioral health and well-being by analyzing quantitative data collected from a baseline assessment of 185 AI/AN urban adolescents from California who were part of a substance use intervention study. Adolescents who identified as AI/AN on their survey reported better mental health, less alcohol and marijuana use, lower rates of delinquency, and increased happiness and spiritual health
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Food insecurity, sleep, and cardiometabolic risks in urban American Indian/Alaska Native youth.
OBJECTIVES: Food insecurity contributes to racial/ethnic disparities in health. This is the first study to examine associations among food insecurity, sleep, and cardiometabolic outcomes in urban American Indian/Alaska Native (AI/AN) youth. DESIGN: Participants were 142 urban AI/AN youth (mean age = 14 years, 58% female). Food insecurity and self-reported sleep disturbance were measured using validated surveys. A multi-dimensional sleep health composite was derived using questionnaires (ie, satisfaction, alertness) and actigraphy-derived indices (ie, duration, efficiency, regularity, timing). Cardiometabolic measures included body mass index, blood pressure, glycosylated hemoglobin, waist circumference, cholesterol, and triglycerides. Covariates were sex, age, and single-parent household. RESULTS: Greater food insecurity was significantly associated with greater body mass index (b = 0.12, p = .015), higher systolic blood pressure (b = 0.93, p = .03), and greater sleep disturbance (b = 1.49, p < .001), and marginally associated with lower sleep health composite scores (b = -0.09, p = .08). There was a significant indirect path from greater food insecurity to greater waist circumference through poorer sleep health (0.11, 95% bootstrapping CI: [0.01, 0.30]). CONCLUSION: Food insecurity is an important correlate of sleep and cardiometabolic health among urban AI/AN youth and should be addressed to reduce emerging health risks during this important developmental period. Policies to reduce food insecurity and increase access to healthy foods as well as sleep interventions for these youth could help, as preliminary findings suggest that sleep health may mediate the negative impact of food insecurity on cardiometabolic risks