The Association Between HIV-Related Stigma and the Uptake of HIV Testing and ART Among Older Adults in Rural South Africa: Findings from the HAALSI Cohort Study

HIV testing and antiretroviral therapy (ART) remain critical for curbing the spread of HIV/AIDS, but stigma can impede access to these services. Using data from the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI), we used a multivariable logistic regression to examine the correlation between HIV-related stigma, HIV testing and ART uptake in older adults. We used four questions to measure stigma, with three assessing social stigma (reflecting social distancing preferences) and one assessing anticipated stigma (disclosure concern). We combined the three social stigma questions to generate a social stigma score ranging from 0 to 3, with higher scores indicating higher stigma. Anticipated stigma was prevalent 85% (95% CI 0.84-0.86), and social stigma was also frequent 25% (95% CI 0.24-0.27). Higher social stigma scores correlated with decreased HIV testing for all participants with social stigma. Compared to those with a score of 0, odds of testing decreased with higher stigma scores (OR = 0.66, 95% CI 0.53-0.81, p = 0.000) for a score of 1 and (OR = 0.56, 95% CI 0.38-0.83, p = 0.004) for a score of 3. ART uptake also decreased with higher social stigma scores among people living with HIV (PLWH), although it was significant for those with a score of 2 (OR = 0.41, 95% CI 0.19-0.87, p = 0.020). These findings emphasize that HIV-related stigma hampers testing and ART uptake among older adults in rural South Africa. Addressing stigma is crucial for improving testing rates, early diagnosis, and treatment initiation among the older population and achieving UNAIDS 95-95-95 targets.

Acceptability and Feasibility of a Smartphone-Based Real-Time Assessment of Suicide Among Black Men: Mixed Methods Pilot Study

BACKGROUND

Suicide rates in the United States have increased recently among Black men. To address this public health crisis, smartphone-based ecological momentary assessment (EMA) platforms are a promising way to collect dynamic, real-time data that can help improve suicide prevention efforts. Despite the promise of this methodology, little is known about its suitability in detecting experiences related to suicidal thoughts and behavior (STB) among Black men.

OBJECTIVE

This study aims to clarify the acceptability and feasibility of using smartphone-based EMA through a pilot study that assesses the user experience among Black men.

METHODS

We recruited Black men aged 18 years and older using the MyChart patient portal messaging (the patient-facing side of the Epic electronic medical record system) or outpatient provider referrals. Eligible participants self-identified as Black men with a previous history of STB and ownership of an Android or iOS smartphone. Eligible participants completed a 7-day smartphone-based EMA study. They received a prompt 4 times per day to complete a brief survey detailing their STB, as well as proximal risk factors, such as depression, social isolation, and feeling like a burden to others. At the conclusion of each day, participants also received a daily diary survey detailing their sleep quality and their daily experiences of everyday discrimination. Participants completed a semistructured exit interview of 60-90 minutes at the study's conclusion.

RESULTS

In total, 10 participants completed 166 EMA surveys and 39 daily diary entries. A total of 4 of the 10 participants completed 75% (21/28) or more of the EMA surveys, while 9 (90%) out of 10 completed 25% (7/28) or more. The average completion rate of all surveys was 58% (20.3/35), with a minimum of 17% (6/35) and maximum of 100% (35/35). A total of 4 (40%) out of 10 participants completed daily diary entries for the full pilot study. No safety-related incidents were reported. On average, participants took 2.08 minutes to complete EMA prompts and 2.72 minutes for daily diary surveys. Our qualitative results generally affirm the acceptability and feasibility of the study procedures, but the participants noted difficulties with the technology and the redundancy of the survey questions. Emerging themes also addressed issues such as reduced EMA survey compliance and diminished mood related to deficit-framed questions related to suicide.

CONCLUSIONS

Findings from this study will be used to clarify the suitability of EMA for Black men. Overall, our EMA pilot study demonstrated mixed feasibility and acceptability when delivered through smartphone-based apps to Black men. Specific recommendations are provided for managing safety within these study designs and for refinements in future intervention and implementation science research.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/31241.

Investigating the Role of Suicidality and Ethnic Identity among Black Adolescents: A Latent Profile Analysis

OBJECTIVE

Suicide among Black adolescent youth has steadily increased in recent years, yet few studies describe how facets of social identity shape suicidal thoughts and behaviors (STBs) during this critical stage of development. Ethnic identity represents an underexplored, yet important element of social identity among Black youth that may contribute to differential associations with STBs. This study examined the association between ethnic identity and self-reported suicidal ideation, planning, and attempts.

METHODS

Data were drawn from 1,170 African American (n = 810) and Caribbean Black (n = 368) adolescents aged 13-17 (Mean age = 15) that participated in the National Survey of American Life Adolescent supplement study.

RESULTS

Using latent profile analyses, three patterns of ethnic identity were identified: Undifferentiated, Low Ethnic Identification, and Alienated. Caribbean Black adolescents were more likely to be in the Low Ethnic Identification class relative to the Undifferentiated class. Adolescents in the Undifferentiated group reported higher proportions of suicidal ideation, planning, and attempts compared to the remaining latent profile groups.

CONCLUSION

Findings demonstrate that ethnic identity is an important aspect of social identity that can influence STBs among Black adolescents. Considering increased suicide attempts and death rates among Black youth, findings underscore the importance of examining culturally relevant developmental processes that may shape suicidal beliefs and behaviors.

The relationship between neighborhood typologies and self-rated health in Maryland: A latent class analysis

Despite widespread evidence that neighborhood conditions impact health, few studies apply theory to clarify the physical and social factors in communities that drive health outcomes. Latent class analysis (LCA) addresses such gaps by identifying distinct neighborhood typologies and the joint influence that neighborhood-level factors play in health promotion. In the current study, we conducted a theory-driven investigation to describe Maryland neighborhood typologies and examined differences in area-level self-rated poor mental and physical health across typologies. We conducted an LCA of Maryland census tracts (n = 1384) using 21 indicators of physical and social characteristics. We estimated differences in tract-level self-rated physical and mental health across neighborhood typologies using global Wald tests and pairwise comparisons. Five neighborhood classes emerged: Suburban Resourced (n = 410, 29.6%), Rural Resourced (n = 313, 22.6%), Urban Underserved (n = 283, 20.4%), Urban Transient (n = 226, 16.3%), Rural Health Shortage (n = 152, 11.0%). Prevalence of self-rated poor physical and mental health varied significantly (p < 0.0001) by neighborhood typology, with the Suburban Resourced neighborhood class demonstrating the lowest prevalence of poor health and the Urban Underserved neighborhoods demonstrating the poorest health. Our results highlight the complexity of defining "healthy" neighborhoods and areas of focus to mitigate community-level health disparities to achieve health equity.

Factors Associated With Suicide in Four West African Countries Among Adolescent Students: An Analysis Using the Global School-Based Student Health Survey

PURPOSE

Globally, suicide is a leading cause of death among adolescents, with the highest burden of suicide occurring in Africa. Despite this, little is known about the epidemiology of suicide among adolescents in West Africa. In this study, we explore suicidality among West African adolescents.

METHODS

Using pooled data from the Global School-Based Student Health Survey in four West African countries (Ghana, Benin, Liberia, and Sierra Leone), we investigated the prevalence of suicidal ideation and suicide attempt and examined associations with 15 covariates using univariate and multivariable logistic regression.

RESULTS

Overall, 18.6% of adolescents in the pooled sample (N = 9,726) had considered suicide, while 24.7% reported attempting suicide. Significant correlates of suicide attempt included older age (16+ years; odds ratio [OR]: 1.70, confidence interval [CI]: 1.09-2.63), difficulty sleeping due to worry (OR: 1.27, CI: 1.04-1.56), loneliness (OR: 1.65, CI: 1.39-1.96), truancy (OR: 1.38. CI: 1.05-1.82), being a target of bullying (OR: 1.53, CI: 1.26-1.85), getting physically attacked (OR: 1.73, CI: 1.42-2.11), physical fighting (OR: 1.47, CI: 1.21-1.79), current cigarette use (OR: 2.71, CI: 1.88-3.89), and initiation of drug use (OR: 2.19, CI: 1.71-2.81). Conversely, having close friends was associated with lower odds of suicide attempt (OR: 0.67, CI: 0.48-0.93). Several covariates were also significantly associated with suicidal ideation.

DISCUSSION

Suicidal ideation and attempts are highly prevalent among school-going adolescents in these West African countries. Multiple modifiable risk and protective factors were identified. Programs, interventions, and policies aimed at addressing these factors may play a significant role in preventing suicides in these countries.

Demographic predictors of emergency service utilization patterns in youth at risk of suicide

OBJECTIVE

To explore demographic predictors of Emergency Department (ED) utilization among youth with a history of suicidality (i.e., ideation or behaviors).

METHODS

Electronic health records were extracted from 2017 to 2021 for 3094 8-22 year-old patients with a history of suicidality at an urban academic medical center ED in the Mid-Atlantic. Logistic regression analyses were used to assess for demographic predictors of ED utilization frequency, timing of subsequent visits, and reasons for subsequent visits over a 24-month follow-up period.

RESULTS

Black race (OR = 1.45, 95% CI = 1.11-1.92), Female sex (OR = 1.59, 95% CI = 1.26-2.03), and having Medicaid insurance (OR = 1.71, 95% CI = 1.37-2.14) were associated with increased utilization, while being under 18 was associated with lower utilization (<12: OR = 0.38, 95% CI = 0.26-0.56; 12-18: OR = 0.47, 95% CI = 0.35-0.63). These demographics were also associated with ED readmission within 90 days, while being under 18 was associated with a lower odds of readmission.

CONCLUSIONS

Among patients with a history of suicidality, those who identify as Black, young adults, patients with Medicaid, and female patients were more likely to be frequent utilizers of the ED within the 2 years following their initial visit. This pattern may suggest inadequate health care access for these groups, and a need to develop better care coordination with an intersectional focus to facilitate utilization of other health services.

Depressive symptoms and their association with age, chronic conditions and health status among middle-aged and elderly people in peri-urban Tanzania

Background

Depression is a global mental health challenge. We assessed the prevalence of depressive symptoms and their association with age, chronic conditions, and health status among middle-aged and elderly people in peri-urban Dar es Salaam, Tanzania.

Methods

Depressive symptoms were measured in 2,220 adults aged over 40 years from two wards of Dar es Salaam using the ten-item version of the Center of Epidemiologic Studies Depression Scale (CES-D-10) and a cut-off score of 10 or higher. The associations of depressive symptoms with age, 13 common chronic conditions, multimorbidity, self-rated health and any limitation in six activities of daily living were examined in univariable and multivariable logistic regressions.

Results

The estimated prevalence of depressive symptoms was 30.7% (95% CI 28.5-32.9). In univariable regressions, belonging to age groups 45-49 years (OR 1.35 [95% CI 1.04-1.75]) and over 70 years (OR 2.35 [95% CI 1.66-3.33]), chronic conditions, including ischemic heart disease (OR 3.43 [95% CI 2.64-4.46]), tuberculosis (OR 2.42 [95% CI 1.64-3.57]), signs of cognitive problems (OR 1.90 [95% CI 1.35-2.67]), stroke (OR 1.56 [95% CI 1.05-2.32]) and anemia (OR 1.32 [95% CI 1.01-1.71]) and limitations in activities of daily living (OR 1.35 [95% CI 1.07-1.70]) increased the odds of depressive symptoms. Reporting good or very good health was associated with lower odds of depressive symptoms (OR 0.48 [95% CI 0.35-0.66]). Ischemic heart disease and tuberculosis remained independent predictors of depressive symptoms in multivariable regressions.

Conclusion

Depressive symptoms affected almost one in three people aged over 40 years. Their prevalence differed across age groups and was moderated by chronic conditions, health status and socioeconomic factors.

Achieving mental health equity in Black male suicide prevention

Despite a steady decrease in suicide rates in the United States, the rate among Black males has increased in recent decades. Moreover, suicide is now positioned as the third leading cause of death in this population, signaling a public health crisis. Enhancing the ability for future suicide prevention scholars to fully characterize and intervene on suicide risk factors is an emerging health equity priority, yet there is little empirical evidence to robustly investigate the alarming trends in Black male suicide. We present fundamental areas of expansion in suicide prevention research focused on establishing culturally responsive strategies to achieve mental health equity. Notably, we identify gaps in existing research and offer future recommendation to reduce suicide death among Black males. Our perspective aims to present important and innovative solutions for ensuring the inclusion of Black males in need of suicide prevention and intervention efforts.

Factor analysis of the Center for Epidemiological Studies Depression Scale in American Indian women

The Center for Epidemiological Studies Depression Scale (CES-D) is widely used to assess depressive symptoms in the general population. It lacks validation for widespread use within the American Indian population, however. To address this gap, we explored and confirmed the factor structure of the CES-D among a community sample of southeastern American Indian women. We analyzed data from a sample of 150 American Indian women ages 18-50 from a southeastern tribe who had complete responses on the CES-D as part of a larger cross-sectional, community-engaged study. We performed exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to assess the measure's validity. We examined EFA models ranging from one to five factors, with the four-factor structure yielding the best overall model fit (CFI = 1.00, TLI = 0.99, RMSEA = 0.03). Differences between the four-factor EFA-retained structure from our sample and Radloff's four-factor structure emerged. Only the interpersonal factor was common to both factor structures. Our study findings confirm the validity of the original four-factor structure of the CES-D for younger adult American Indian women in the southeast. Contrasting findings with the EFA-retained structure, however, provide a more nuanced interpretation of our results.

Rapid and Deferred Help Seeking Among African American Parents of Children With Emotional and Behavioral Difficulties

OBJECTIVE

Little is known about the factors African American parents consider when seeking care for their child after emotional and behavioral difficulties emerge. This study aimed to examine factors associated with seeking professional care within 30 days after identifying a child's need (i.e., rapid care seeking) and with deferring care for ≥1 year.

METHODS

This cross-sectional study surveyed African American parents raising a child with emotional or developmental challenges (N=289). Logistic regression was used to examine associations of parent activation, medical mistrust, and care-seeking barriers with two outcomes: rapidly seeking care and deferring care seeking.

RESULTS

About 22% of parents rapidly sought care, and 49% deferred care for 1 year or longer. Parents were more likely to rapidly seek care if they had higher parent activation scores; lived with other adults with mental health challenges; or, contrary to the authors' hypothesis, mistrusted doctors. Parents were less likely to rapidly seek care if the challenge did not initially bother them much or if their health insurance would not cover the service. Parents were more likely to defer care if they feared involuntary hospitalization for their child or if their health insurance would not cover the service. Parents were less likely to defer care if they had at least some college education or lived with other adults with mental health challenges.

CONCLUSIONS

Community-based pediatric and child welfare professionals should be informed about facilitators and barriers to mental health care seeking as part of efforts to develop interventions that support African American families.

Typologies of mental healthcare discrimination experiences and associations with current provider care ratings: A latent class analysis

Background

Discrimination is experienced across demographic attributes (e.g., race and gender) and vantage points (e.g., personal and vicarious), yet few studies have classified these different experiences of discrimination within healthcare systems. Moreover, which discriminatory experiences have greater influence on patient-reported quality outcomes remains poorly understood. To address these gaps, we used latent class analysis (LCA) to identify typologies of past experiences with healthcare discrimination among adults with depression-who experience more frequent and stigmatizing healthcare interactions than the general population-and assess the relationship between class membership and current ratings of patient-reported quality outcomes.

Methods

We surveyed a nationally representative sample of adults with depression (n = 803) to assess past experiences of discrimination by medical providers in terms of both the characteristics targeted for discrimination and whether healthcare discrimination was experienced personally or by friends and family members. We conducted an LCA to identify discrimination-exposure classes and a modified Poisson regression to identify associations between class membership and patient-reported quality outcomes (e.g., overall medical provider quality, respect, clear communication, and careful listening), while adjusting for covariates.

Results

We identified four latent classes of healthcare discrimination: low discrimination (LD; referent class: 72.2% of total sample), vicarious linguistic discrimination (VL; 13.9%), elevated personal and vicarious racial discrimination (EPVR; 10.5%), and high racial/ethnic discrimination (HRE; 3.4%). Compared to those in the LD class, individuals in the EPVR class had higher rates of reporting their current medical provider's respect and careful listening skills as sometimes or never, (Respect aIRR: 1.90, 95% CI: 1.05-3.42; Listening aIRR: 2.18, 95% CI: 1.29-3.66). Those in the HRE class reported higher rates of reporting their medical provider's quality and communication as poor or fair and lower ratings of careful listening (Quality aIRR: 2.06, 95% CI: 1.08-3.93; Communication aIRR: 1.97, 95% CI: 1.00-3.63; Listening aIRR: 2.41, 95% CI: 1.27-4.59), compared to those in the LD class. Those in the VL class had higher rates of reporting that their medical provider never or sometimes respected or carefully listened to them (Respect aIRR: 2.12, 95% CI: 1.20-3.72; Listening aIRR:1.67, 95% CI:1.03-2.71) than those in, the LD class.

Conclusions

Healthcare organizations committed to providing equitable patient care should establish more robust quality improvement approaches to prevent discrimination at the medical provider level as well as structures of accountability to reconcile previously embedded social inequities within the healthcare system.

Methodological Considerations in Scale Refinement with Diverse Populations: A Case Example Using the CES-D with a Community Sample of American Indian Women

Although many psychometric assessments are used extensively in population-based research to determine psychopathology, these tools have not been thoroughly validated or appropriately adapted for use in diverse populations. Indeed, depression measurement studies among American Indian and female populations are scarce, omitting key opportunities to tailor psychological measurement for this population. To build psychometric evidence of measures in this population, we used a procedural method to examine a standard psychological instrument-the Center for Epidemiological Studies Depression Scale (CES-D)-with a community sample of southeast American Indian women. Our results showed strong psychometric reliability of the 20-item CES-D. The "effort" item presented diminished validity, as demonstrated by a negative counter-intuitive item-to-total correlation (ITC) value. Dropping the "effort" item resulted in a 19-item scale with a better fit in the within-group examination of community-based American Indian women. Compared to the 20-item CES-D scale, the revised 19-item measure ("effort" item removed) resulted in minimal changes to women's depression categories. However, we did detect patterns in shifts such that the 19-item scale generally underestimated (i.e., placed women in a lower category) depressive symptoms compared to the 20-item scale. Depending on their study goals, researchers engaging in population-based research should carefully weigh the use of original scales that allow for consistency in reporting with refined scales that fit psychometrically. We present the outlined method as a tool that expands on current approaches in scale refinement, and aids researchers in making more informed decisions regarding refined scales with diverse populations.

Perceived healthcare discrimination and well-being among older adults in the United States and Brazil

Despite well-documented evidence illustrating the relationship between discrimination and health, less is known about the influence of unfair treatment when receiving medical care. Moreover, our current knowledge of cross-national and racial variations in healthcare discrimination is limited in aging populations. This article addresses these gaps using two harmonized data sets of aging populations to clarify the relationship between healthcare discrimination and health in the United States and Brazil. We use nationally representative, harmonized data from the Health and Retirement Study in the United States and the Brazilian Longitudinal Study of Aging to examine and compare perceived discrimination in the healthcare setting and its relationship to self-rated health, depression diagnosis, and depressive symptoms across national contexts. Using Poisson regression models and population attributable risk percent estimates, we found that aging adults reporting healthcare discrimination were at higher risk of poor self-rated health, diagnosed depression, and depressive symptoms. Our results also suggest that reducing perceived healthcare discrimination may contribute to improved self-rated health and mental well-being in later life across racialized societies. In two comparative settings, we highlight the differential impact of healthcare discrimination on self-rated health and depression. We describe the implications of our study's findings for national public health strategies focused on eliminating discrimination in the healthcare setting, particularly among aging countries.

Barriers to and facilitators of vocational development for Black young adults with serious mental illnesses

OBJECTIVE

Black young adults with serious mental illnesses (SMI) have low rates of employment and school completion. Racial disparities exist in the delivery of vocational services, with Black people less likely to be screened in, and if screened in less likely to receive job training. This qualitative exploratory study examined how Black young adults with SMI perceive the barriers and facilitators to achieving their vocational goals.

METHOD

Our conceptual model for this study is the Social-Ecological Model (SEM), which contains four domains of analysis (intrapersonal, interpersonal, community, and societal), informed by Critical Race Theory (CRT). We completed semistructured, qualitative interviews with 28 Black young adults with SMI. We analyzed data using qualitative content and inductive analyses.

RESULTS

Numerous respondents were experiencing racial discrimination in their vocational pursuits and their lives overall, and expressed doubts about achieving vocational success in racially imbalanced environments. Facilitating their vocational growth was trusting relationships with nonjudgmental and understanding vocational counselors (VC) who provided supports reflecting client preferences. As college students, respondents benefited from the presence and accessibility of Black faculty and students. As employees, they valued workplace supervisors who provided direct support and feedback.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

Black young adults with SMI face high and racialized barriers to pursuing work and education at multiple socioecological levels. The field of psychiatric rehabilitation should prepare VCs to understand and address the needs and expressed preferences of Black young adults with SMI. Also called for is research, centered on and directed by Black communities, on the effectiveness of race-conscious vocational practices. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Adolescents' Concerns About School Violence or Shootings and Association With Depressive, Anxiety, and Panic Symptoms

IMPORTANCE

The prevalence of internalizing problems among US adolescents has risen in the past decade. The extent to which concerns about school violence or shootings are associated with risk of internalizing problems is unknown.

OBJECTIVE

To examine the prospective association of concern, worry, and stress related to school violence or shootings with internalizing problems and to examine sex and racial and ethnic differences in the magnitude of the associations.

DESIGN, SETTING, AND PARTICIPANTS

This longitudinal cohort study involved 3 surveys administered 6 months apart (fall of grade 11 [prebaseline]; spring of grade 11 [baseline]; and fall of grade 12 [follow-up]) from 2015 to 2016. Participants included 2263 students from 10 high schools in Los Angeles, California. Analyses were performed from April 29, 2020, to April 8, 2021.

EXPOSURES

Baseline self-reported level of concern, worry, and stress about shootings or violence at the student's school or other schools, each rated on 5-point scales (ranging from not at all [0] to extremely [4]) with a mean score calculated as a 3-item composite index rescaled into z-score standard deviation units.

MAIN OUTCOMES AND MEASURES

Surpassing clinically significant or borderline significant thresholds for major depressive disorder, generalized anxiety disorder, or panic disorder based on symptom ratings on the Revised Children's Anxiety and Depression Scale at 6-month follow-up.

RESULTS

Of the 2263 students included in the analyses (1250 [55.2%] girls; mean [SD] age, 16.5 [0.4] years), appreciable proportions reported being very or extremely concerned (850 0f 2226 [38.2%]), worried (703 of 2209 [31.8%]), or stressed (332 of 2183 [15.2%]) about shootings or violence at their school or other schools. After adjusting for prebaseline covariates, concerns about school violence or shootings were associated with clinically significant generalized anxiety symptoms (odds ratio [OR], 1.31; 95% CI, 1.15-1.50) and panic symptoms (OR, 1.18; 95% CI, 1.05-1.32), but not depressive symptoms (OR, 1.13; 95% CI, 0.99-1.30) at the 6-month follow-up. There was a significant association between concern with school violence or shootings and depressive symptoms for Black youth (OR, 3.15; 95% CI, 1.38-7.19) and non-Hispanic/Latinx White youth (OR, 1.62 [95% CI, 1.25-2.09]) but not for youth of other races and ethnicities (OR for Asian, 1.26 [95% CI, 0.86-1.85]; OR for Hispanic/Latinx, 0.94 [95% CI, 0.76-1.16]; OR for other, 0.93 [95% CI, 0.54-1.61]). Sex did not moderate these associations.

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that concern, worry, and stress related to school violence or shootings may be risk factors for internalizing problems among adolescents, with variation in the strength of the association by race/ethnicity.

Community Health Worker Training Curricula and Intervention Outcomes in African American and Latinx Communities: A Systematic Review

In recent years, community health workers (CHWs) have emerged as key stakeholders in implementing community-based public health interventions in racially diverse contexts. Yet little is known about the extent to which CHW training curriculums influence intervention effectiveness in marginalized racial and ethnic minority communities. This review summarizes evidence on the relationship between CHW training curricula and intervention outcomes conducted among African American and Latinx populations. We conducted a literature search of intervention studies that focused on CHW public health interventions in African American and Latinx populations using PubMed, PsycINFO, ERIC, CINAHL, EMBASE, and Web of Science databases. Included studies were quantitative, qualitative, and mixed methods studies employed to conduct outcome (e.g., blood pressure and HbA1c) and process evaluations (e.g., knowledge and self-efficacy) of CHW-led interventions. Out of 3,295 articles from the database search, 36 articles met our inclusion criteria. Overall, the strength of evidence linking specific CHW training curricula components to primary intervention health outcomes was weak, and no studies directly linked outcomes to specific characteristics of CHW training. Studies that described training related to didactic sessions or classified as high intensity reported higher percentages of positive outcomes compared to other CHW training features. These findings suggest that CHW training may positively influence intervention effectiveness but additional research using more robust methodological approaches is needed to clarify these relationships.

Refining Black men's depression measurement using participatory approaches: a concept mapping study

Background

Despite cumulative socioeconomic disadvantage and risk factors, Black Americans have a lower prevalence of depression than whites. Given the emerging focus of depression as a public mental health crisis, culturally informed depression measures and scale development techniques are needed to better alleviate the mental health burden of socially marginalized populations. Yet, for Black men, race- and gender-related factors that position emotional vulnerability as a sign of weakness, may potentially mask the timely identification of mental health needs in this population. Thus, we address these gaps by employing a stakeholder-driven, community-engaged process for understanding Black men’s depression experience.

Methods

We use concept mapping, a structured mixed methods approach, to determine how stakeholders of Black men’s health conceptualize their depressive symptoms. Thirty-six stakeholders participated in a three-phase concept mapping study conducted in 2018. Three separate stakeholder groups were engaged for this study, including Black men, Black women, and primary care providers.

Results

Participants generated 68 characteristics of Black men’s depression which were reflected within five conceptual clusters: (1) physical states; (2) emotional states; (3) diminished drive; (4) internal conflicts; (5) communication with others; and (6) social pressures. Using a content analysis approach, we found that items comprising the “social pressures” cluster were not reflected in any common depression scales.

Conclusions

Findings from this study illustrate the similar and divergent pathways in which Black men express depressed mood. Furthermore, concept mapping results also yield a novel opportunity for culturally informed scale development in future research.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11137-5.

Association between psychological resilience and changes in mental distress during the COVID-19 pandemic

BACKGROUND

Psychological responses to potentially traumatic events tend to be heterogeneous, with some individuals displaying resilience. Longitudinal associations between resilience and mental distress during the COVID-19 pandemic, however, are poorly understood. The objective of this study was to examine the association between resilience and trajectories of mental distress during the COVID-19 pandemic.

METHODS

Participants were 6,008 adults from the Understanding America Study, a probability-based Internet-panel representative of the US adult population. Baseline data were collected between March 10 and March 31, 2020, with nine follow-up waves conducted between April 1 and August 4. Mixed-effects logistic regression was used to examine the association between date and mental distress, stratified by resilience level (low, normal, or high).

RESULTS

In contrast to the high resilience group, participants in the low and normal resilience groups experienced increases in mental distress in the early months of the pandemic (low: OR=2.94, 95% CI=1.93-4.46; normal: OR=1.91, 95% CI=1.55-2.35). Men, middle-aged and older adults, Black adults, and adults with a graduate degree were more likely to report high resilience, whereas adults living below the poverty line were less likely to report high resilience.

LIMITATIONS

These associations should not be interpreted as causal, and resilience was measured at only one time-point.

CONCLUSIONS

Trajectories of mental distress varied markedly by resilience level during the early months of the COVID-19 pandemic, with low-resilience adults reporting the largest increases in mental distress during this crisis. Activities that foster resilience should be included in broader strategies to support mental health throughout the pandemic.

Parent Activation and Child Mental Health Service use in African American Families in a Large Cross-Sectional Study

OBJECTIVES

1) To describe activation skills of African American parents on behalf of their children with mental health needs. 2) To assess the association between parent activation skills and child mental health service use.

METHODS

Data obtained in 2010 and 2011 from African American parents in North Carolina raising a child with mental health needs (n = 325) were used to identify child mental health service use from a medical provider, counselor, therapist, or any of the above or if the child had ever been hospitalized. Logistic regression was used to model the association between parent activation and child mental health service use controlling for predisposing, enabling, and need characteristics of the family and child.

RESULTS

Mean parent activation was 65.5%. Over two-thirds (68%) of children had seen a medical provider, 45% had seen a therapist, and 36% had seen a counselor in the past year. A quarter (25%) had been hospitalized. A 10-unit increase in parent activation was associated with a 31% higher odds that a child had seen any outpatient provider for their mental health needs (odds ratio = 1.31, confidence interval = 1.03-1.67, p = 0.03). The association varied by type of provider. Parent activation was not associated with seeing a counselor or a therapist or with being hospitalized.

CONCLUSION

African American families with activation skills are engaged and initiate child mental health service use. Findings provide a rationale for investing in the development and implementation of interventions that teach parent activation skills and facilitate their use by practices in order to help reduce disparities in child mental health service use.

Dimensionality and differential item endorsement of depressive symptoms among aging Black populations in South Africa: Findings from the HAALSI study

BACKGROUND

The Center for Epidemiologic Studies-Depression (CES-D) scale is a widely used measure of depressive symptoms, but its construct validity has not been adequately assessed in sub-Saharan Africa. This study validates the CES-D among an aging Shangaan-speaking and predominantly Black African sample in rural South Africa, with a special emphasis on gender differences.

METHODS

An 8-item CES-D scale was administered in Shangaan to 5059 respondents, aged 40+ years, residing in Agincourt, South Africa. We used Cronbach's alpha and exploratory and confirmatory factor analysis to examine and confirm dimensionality of the CES-D scale. Differential endorsement of CES-D items by gender were assessed using the Mantel-Haenszel (MH) odds ratio test.

RESULTS

Reliability of the CES-D scale differed by gender with women reporting higher internal consistency on items than men. A two-factor solution was retained and confirmed representing two latent factors: (1) Negative Affect (six items) and (2) Diminished Positive Affect (two items). MH results showed that men exhibited significantly higher odds of putting an effort in everything that they did (OR: 1.33, 95% CI: 1.15-1.54) and lower odds of feeling depressed (OR: 0.71, 95% CI: 0.56-0.89) and having restless sleep (OR: 0.67, 95% CI:0.58-0.77) than women.

LIMITATIONS

Analyses were limited to a dichotomous, short form of the CES-D, a self-reported population-based measure.

CONCLUSION

Aging Black Africans differ in endorsing affective and somatic items on the CES-D scale by gender, which may lead to skewed population-level estimates of depression in key subpopulations. These findings highlight the importance of continued research disentangling cross-cultural and gendered nuances of depression measurements.

Understanding the Role of Past Health Care Discrimination in Help-Seeking and Shared Decision-Making for Depression Treatment Preferences

As a part of a larger, mixed-methods research study, we conducted semi-structured interviews with 21 adults with depressive symptoms to understand the role that past health care discrimination plays in shaping help-seeking for depression treatment and receiving preferred treatment modalities. We recruited to achieve heterogeneity of racial/ethnic backgrounds and history of health care discrimination in our participant sample. Participants were Hispanic/Latino (n = 4), non-Hispanic/Latino Black (n = 8), or non-Hispanic/Latino White (n = 9). Twelve reported health care discrimination due to race/ethnicity, language, perceived social class, and/or mental health diagnosis. Health care discrimination exacerbated barriers to initiating and continuing depression treatment among patients from diverse backgrounds or with stigmatized mental health conditions. Treatment preferences emerged as fluid and shaped by shared decisions made within a trustworthy patient-provider relationship. However, patients who had experienced health care discrimination faced greater challenges to forming trusting relationships with providers and thus engaging in shared decision-making processes.

Addressing Major Health Disparities Related to Coronavirus for People With Behavioral Health Conditions Requires Strength-Based Capacity Building and Intentional Community Partnership

Far from being an equalizer, as some have claimed, the COVID‐19 pandemic has exposed just how vulnerable many of our social, health, and political systems are in the face of major public health shocks. Rapid responses by health systems to meet increased demand for hospital beds while continuing to provide health services, largely via a shift to telehealth services, are critical adaptations. However, these actions are not sufficient to mitigate the impact of coronavirus for people from marginalized communities, particularly those with behavioral health conditions, who are experiencing disproportional health, economic, and social impacts from the evolving pandemic. Helping these communities weather this storm requires partnering with existing community‐based organizations and local governments to rapidly and flexibly meet the needs of vulnerable populations.

Factor Analysis of the CES-D 12 among a Community Sample of Black Men

The Center for Epidemiologic Studies Depression (CES-D) scale is one of the most widely used measures for assessing depression in population-based research. Little is known about the varying range of symptomatology expressed by Black men, who report higher chronicity and disability of their depressive symptoms compared to men of other racial and ethnic backgrounds. This study assessed the dimensional structure of the CES-D 12-item scale using exploratory and confirmatory factor analysis in a community-based sample of Black men (n = 683). Two latent factors emerged from the scale that best fit the data: interpersonal negative affect (INA) and diminished positive affect (DPA). The item “I felt like everything I did was an effort” was removed from the final measure, resulting in an 11-item scale. The total score for the revised CES-D-11 displayed acceptable internal consistency on both latent factors (Cronbach’s α = 0.83 [INA] and 0.73 [DPA]) and model fit (χ² = 165.58, TLI = 0.967, CFI = 0.974, RMSEA = 0.065). Results differ from CES-D factor analyses in other demographic groups, including studies with other male subpopulations, such that depressed mood and interpersonal problems factors are merged as a unidimensional construct. Findings suggest that the “effort” item from the CES-D 12 should be interpreted with caution among Black men. Future studies should continue to disentangle the divergent pathways in which Black men express depressed mood.

Medical Mistrust and Colorectal Cancer Screening Among African Americans

Despite well-documented benefits of colorectal cancer (CRC) screening, African Americans are less likely to be screened and have higher CRC incidence and mortality than Whites. Emerging evidence suggests medical mistrust may influence CRC screening disparities among African Americans. The goal of this systematic review was to summarize evidence investigating associations between medical mistrust and CRC screening among African Americans, and variations in these associations by gender, CRC screening type, and level of mistrust. MEDLINE, CINAHL, Web of Science, PsycINFO, Google Scholar, Cochrane Database, and EMBASE were searched for English-language articles published from January 2000 to November 2016. 27 articles were included for this review (15 quantitative, 11 qualitative and 1 mixed methods study). The majority of quantitative studies linked higher mistrust scores with lower rates of CRC screening among African Americans. Most studies examined mistrust at the physician level, but few quantitative studies analyzed mistrust at an organizational level (i.e. healthcare systems, insurance, etc.). Quantitative differences in mistrust and CRC screening by gender were mixed, but qualitative studies highlighted fear of experimentation and intrusiveness of screening methods as unique themes among African American men. Limitations include heterogeneity in mistrust and CRC measures, and possible publication bias. Future studies should address methodological challenges found in this review, such as limited use of validated and reliable mistrust measures, examination of CRC screening outcomes beyond beliefs and intent, and a more thorough analysis of gender roles in the cancer screening process.

Masculinity and Race-Related Factors as Barriers to Health Help-Seeking Among African American Men

Men's tendency to delay health help-seeking is largely attributed to masculinity, but findings scarcely focus on African American men who face additional race-related, help-seeking barriers. Building principally on reactance theory, we test a hypothesized model situating racial discrimination, masculinity norms salience (MNS), everyday racism (ERD), racial identity, sense of control (SOC), and depressive symptomatology as key barriers to African American men's health help-seeking. A total of 458 African American men were recruited primarily from US barbershops in the Western and Southern regions. The primary outcome was Barriers to Help-Seeking Scale (BHSS) scores. The hypothesized model was investigated with confirmatory factor and path analysis with tests for measurement invariance. Our model fit was excellent [Formula: see text] CFI = 0.99; TLI = 1.00; RMSEA = 0.00, and 90% CI [0.00, 0.07] and operated equivalently across different age, income, and education strata. Frequent ERD and higher MNS contributed to higher BHHS scores. The relationship between ERD exposure and BHHS scores was partially mediated by diminished SOC and greater depressive symptomatology. Interventions aimed at addressing African American men's health help-seeking should not only address masculinity norms but also threats to sense of control, and negative psychological sequelae induced by everyday racism.

Gender Differences in Service Utilization among OEF/OIF Veterans with Posttraumatic Stress Disorder after a Brief Cognitive-Behavioral Intervention to Increase Treatment Engagement: A Mixed Methods Study

PURPOSE

Women veterans who served in Iraq and Afghanistan (Operation Enduring Freedom and Operation Iraqi Freedom [OEF/OIF]) have a moderately higher risk of developing posttraumatic stress disorder (PTSD) than male veterans. However, gender disparities in treatment engagement may prevent women veterans from initiating the care they need. Understanding gender differences in predictors of and barriers to treatment is essential to improving engagement and mental health outcomes. The purpose of this study was to examine gender differences in treatment utilization after a brief, cognitive-behavioral therapy (CBT) intervention among male and female OEF/OIF veterans.

METHODS

Participants were assigned randomly to either the intervention or control conditions. Intervention participants received the telephone-based CBT intervention. Participants were 35 female and 238 male OEF/OIF veterans who screened positive for PTSD and had never initiated PTSD treatment. Participants were asked about treatment utilization, beliefs about PTSD treatment, and symptoms at months 1, 3, and 6 months subsequent to the baseline telephone assessment. The PTSD Checklist-Military Version was used to assess PTSD and the Patient's Health Questionnaire was used to assess symptoms of depression.

FINDINGS

Female veterans who received an intervention were significantly more likely to have attended treatment over the 6-month follow-up period than male veterans who received an intervention (χ(2) = 7.91; df = 3; odds ratio, 3.93; p = .04).

CONCLUSIONS

The CBT intervention may be a critical mechanism to engage female veterans in treatment. Further research is needed to understand how to engage male veterans with PTSD in treatment.

A comparative encyclopedia of DNA elements in the mouse genome

The laboratory mouse shares the majority of its protein-coding genes with humans, making it the premier model organism in biomedical research, yet the two mammals differ in significant ways. To gain greater insights into both shared and species-specific transcriptional and cellular regulatory programs in the mouse, the Mouse ENCODE Consortium has mapped transcription, DNase I hypersensitivity, transcription factor binding, chromatin modifications and replication domains throughout the mouse genome in diverse cell and tissue types. By comparing with the human genome, we not only confirm substantial conservation in the newly annotated potential functional sequences, but also find a large degree of divergence of sequences involved in transcriptional regulation, chromatin state and higher order chromatin organization. Our results illuminate the wide range of evolutionary forces acting on genes and their regulatory regions, and provide a general resource for research into mammalian biology and mechanisms of human diseases.

An encyclopedia of mouse DNA elements (Mouse ENCODE)

To complement the human Encyclopedia of DNA Elements (ENCODE) project and to enable a broad range of mouse genomics efforts, the Mouse ENCODE Consortium is applying the same experimental pipelines developed for human ENCODE to annotate the mouse genome.

Scaled cortical impact in immature swine: effect of age and gender on lesion volume

The piglet scaled cortical impact model creates a focal contusion using a skull-mounted, spring-loaded blunt indentation device scaled to achieve identical tissue strains in subjects with different brain sizes. Preliminary data showed that contusion size increased proportional to subject age. This study details the results from a new, larger series of subjects of three ages, and compares the effect of age and additional host and physiologic variables on injury response. Sixty-seven subjects, including infant (5- to 7-day-old), "toddler" (1-month-old), and early adolescent (4-month-old) swine underwent scaled cortical impact under strict anesthetic protocols. Serum glucose, testosterone, and 17beta-estradiol levels were measured. Lesion size was measured at 1 week post injury, as the ratio of the lesion area over the area of the contralateral hemisphere. Adolescent subjects had lesions over eight times larger than infants (p < 0.0001). Lesion volumes were larger in toddlers than in infants, most significantly for males (p < 0.05). Adolescent subjects were warmer on average, but there was no correlation between temperature and lesion volume within any age group. Serum glucose did not differ among ages. Infant males had the highest levels of circulating sex steroids. In this model, age was the most robust predictor of lesion size. Temperature had an effect, but did not explain all the variability seen among age groups. There was an interaction among gender, hormone levels, and lesion size in younger subjects. Characterization of these variables allows use of this model for treatment trials for subjects at different stages of maturation.

Expression and characterization of recombinant interferon gamma (IFN-gamma) from the nine-banded armadillo (Dasypus novemcinctus) and its effect on Mycobacterium leprae-infected macrophages

Armadillos (Dasypus novemcinctus) manifest the full histopathological spectrum of leprosy, and are hosts of choice for in vivo propagation of Mycobacterium leprae. Though potentially useful as a model of leprosy pathogenesis, few armadillo-specific reagents exist. We have identified a region of high homology to the interferon gamma (IFN-gamma) of other mammals within the recently published armadillo whole genomic sequence. cDNA was made from ConA-stimulated armadillo peripheral blood mononuclear cells (PBMC), amplified, and cloned into a pET expression vector for transformation and over-expression in Escherichia coli. The recombinant protein (rDnIFN-gamma) was characterized by western blot and its biological function confirmed with bioassays including intracellular killing of Toxoplasma gondii and induction of indoleamine 2, 3-dioxygenase activity. In using rIFN-gamma to activate macrophages from mice, humans or armadillos, similar to humans, rIFN-gamma-activated armadillo MPhi did not produce nitrite and or inhibit the viability of M. leprae in vitro. Conversely, murine rIFN-gamma-activated mouse MPhi produced high levels of nitrite and killed intracellular M. leprae in vitro. These data indicate that the response of armadillo MPhi to rDnIFN-gamma is similar to that which occurs in humans, and demonstrates a potentially important value of the armadillo as a model in leprosy research.

The continuing challenges of leprosy

Leprosy is best understood as two conjoined diseases. The first is a chronic mycobacterial infection that elicits an extraordinary range of cellular immune responses in humans. The second is a peripheral neuropathy that is initiated by the infection and the accompanying immunological events. The infection is curable but not preventable, and leprosy remains a major global health problem, especially in the developing world, publicity to the contrary notwithstanding. Mycobacterium leprae remains noncultivable, and for over a century leprosy has presented major challenges in the fields of microbiology, pathology, immunology, and genetics; it continues to do so today. This review focuses on recent advances in our understanding of M. leprae and the host response to it, especially concerning molecular identification of M. leprae, knowledge of its genome, transcriptome, and proteome, its mechanisms of microbial resistance, and recognition of strains by variable-number tandem repeat analysis. Advances in experimental models include studies in gene knockout mice and the development of molecular techniques to explore the armadillo model. In clinical studies, notable progress has been made concerning the immunology and immunopathology of leprosy, the genetics of human resistance, mechanisms of nerve injury, and chemotherapy. In nearly all of these areas, however, leprosy remains poorly understood compared to other major bacterial diseases.

Expression of nine-banded armadillo (Dasypus novemcinctus) interleukin-2 in E. coli

The nine-banded armadillo (Dasypus novemcinctus) is the only immunologically intact animal that regularly develops lepromatous-type leprosy when inoculated with Mycobacterium leprae. However, the ability to exploit this model for understanding the pathogenesis of leprosy has been limited by a lack of suitable immunological reagents. Recently, efforts began to sequence the entire armadillo genome, and this sequence information will help make possible the development of a wide array of new immunological reagents suitable for use with armadillos. Using the available sequence data, a region of high homology to interleukin-2 of other mammals was identified. Primers were designed to amplify the coding region corresponding to the mature peptide and its exact sequence was confirmed. cDNA was made from ConA-stimulated armadillo PBMC. The amplified coding region was sub-cloned into a pET expression vector and transformed into Escherichia coli for over-expression. The subsequent product was characterized by SDS-PAGE and bioassays. Tritiated thymidine incorporation by CTLL-2 and armadillo lymphoblasts confirmed functionality of the recombinant product. The advent of the D. novemcinctus genome sequence and subsequent generation of immunological tools will assist in advancing the armadillo as a translational model for leprosy.

Mycobacterium leprae-specific, HLA class II-restricted killing of human Schwann cells by CD4+ Th1 cells: a novel immunopathogenic mechanism of nerve damage in leprosy

Peripheral nerve damage is a major complication of reversal (or type-1) reactions in leprosy. The pathogenesis of nerve damage remains largely unresolved, but detailed in situ analyses suggest that type-1 T cells play an important role. Mycobacterium leprae is known to have a remarkable tropism for Schwann cells of the peripheral nerve. Reversal reactions in leprosy are often accompanied by severe and irreversible nerve destruction and are associated with increased cellular immune reactivity against M. leprae. Thus, a likely immunopathogenic mechanism of Schwann cell and nerve damage in leprosy is that infected Schwann cells process and present Ags of M. leprae to Ag-specific, inflammatory type-1 T cells and that these T cells subsequently damage and lyse infected Schwann cells. Thus far it has been difficult to study this directly because of the inability to grow large numbers of human Schwann cells. We now have established long-term human Schwann cell cultures from sural nerves and show that human Schwann cells express MHC class I and II, ICAM-1, and CD80 surface molecules involved in Ag presentation. Human Schwann cells process and present M. leprae, as well as recombinant proteins and peptides to MHC class II-restricted CD4(+) T cells, and are efficiently killed by these activated T cells. These findings elucidate a novel mechanism that is likely involved in the immunopathogenesis of nerve damage in leprosy.

Exploitation of gene knockout mice models to study the pathogenesis of leprosy

Shepard's technique for growth of Mycobacterium leprae in the mouse footpad, described in 1960, and more recent studies in thymectomized-irradiated mice and rats, athymic nude mice, nude rats and severe combined immunodeficiency (SCID) mice have defined the role of T-cell mediated immunity (CMI) in leprosy. However, the normal mouse and the immunocompromised mouse and rat represent only elements of polar tuberculoid disease and polar lepromatous leprosy, respectively. Transgenic, knockout (KO) mice may be employed to study the roles of individual genes in the ability of the host to mount an effective immune response to pathogens, and may also allow development of mouse models for the immunologically unstable borderline areas of the spectrum. We are exploiting certain KO mice to improve our understanding of CMI to M. leprae, and to study the role of the microenvironment of the leprosy granuloma in pathogenesis. CGD (chronic granulomatous disease) mice and iNOS-KO mice lack the ability to produce reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI), respectively, whereas the T cells of GKO mice are unable to produce interferon-gamma (IFN gamma). iNOS-KO mice exhibit an enhanced capacity to form granulomas, and the histopathology of the infected footpad tissues of this strain share many elements of borderline tuberculoid disease. The macrophages of CGD mouse kill or inhibit multiplication of M. leprae, although they lack ROI. Multiplication of the organisms in the footpad is enhanced in GKO mice, although these mice retain some host resistance. In addition, we have been investigating supplementary, conditional approaches to KO mouse models. For example, the down-regulatory effects of local prostaglandin production can be controlled with essential fatty acid deficient diets or indomethacin, RNI can be blocked in CGD and GKO mice by treatment with aminoguanidine, NG monomethyl arginine or N6-(1-iminoethyl)-L-lysine, and local elaboration of TNF alpha can be neutralized by anti-TNF alpha antibody or excess TNF alpha receptor. Other cytokines can be neutralized by antibody as well, broadening the range of conditional knockout models.

Role of inducible nitric oxide synthase in resistance to Mycobacterium leprae in mice

The manifestation of leprosy in humans is largely determined by host immunity to Mycobacterium leprae and is a model for immunoregulation in a human disease. However, animal models available for exploration of the leprosy spectrum are inadequate. This study explored M. leprae infection in mice deficient in inducible nitric oxide synthase, and this report describes elements resembling borderline tuberculoid leprosy in humans.

Agelasine F from a Philippine Agelas sp. sponge exhibits in vitro antituberculosis activity

Marine sponge samples were collected in Baler, Aurora, Philippines, and extracts were tested for in vitro antituberculosis activity. An orange Agelas sp. sponge yielded the known compound, agelasine F, which inhibited some drug resistant strains of Mycobacterium tuberculosis in vitro at concentrations as low as 3.13 micrograms/ml. Activity against M. tuberculosis residing within macrophages required concentrations of 13-22 micrograms/ml which was below the IC50 for Vero cells (34 micrograms/ml).

Inhibition of metabolism and growth of Mycobacterium leprae by gamma irradiation

Mycobacterium leprae is uncultivable on artificial medium, but viability can be maintained without multiplication for a limited time in vitro. In this study, we evaluated gamma-irradiation (gamma-irr) as a means to kill this slowly growing organism. Freshly harvested, viable, athymic, nu/nu mouse-derived M. leprae were exposed to varying doses of gamma-irr from a 60Co source. Two indicators of bacterial viability were determined: metabolism, measured by oxidation of 14C-palmitic acid to 14CO2 in the BACTEC 460 system, and multiplication, measured by titration in the mouse foot pad. gamma-Irr of both M. leprae and M. lufu, a cultivable control mycobacterium, resulted in a dose-dependent inhibition of viability. gamma-Irr of up to 10(3) rad had little effect on the metabolic activity of either organism. For M. leprae, 10(4)-10(5) rad caused an intermediate inhibitory effect; whereas 10(6) rad yielded almost total inhibition. In the mouse foot pad assay, up to 10(4) rad had little effect on M. leprae growth; however, 10(5) rad resulted in at least a 2-log reduction in the number of bacilli recovered and no M. leprae growth was measurable after exposure to 10(6) rad. With M. lufu, 10(5) rad inhibited metabolic activity by 99% and caused > or = 2-log reduction in the number of colony forming units (CFU). No CFU of M. lufu were recovered after exposure to 10(6) rad. Scanning electron microscopy revealed the presence of some aberrant protrusions on the cell surface of lethally irradiated M. leprae; whereas boiling and autoclaving caused obvious morphological denaturation. These data suggest that gamma-irr is an effective way to kill M. leprae without causing extensive damage to the cell architecture. Killing M. leprae by gamma-irr may be preferable when comparing cellular responses to live versus dead bacilli in vitro and in vivo.

Effective treatment of acute and chronic murine tuberculosis with liposome-encapsulated clofazimine

The therapeutic efficacy of liposomal clofazimine (L-CLF) was studied in mice infected with Mycobacterium tuberculosis Erdman. Groups of mice were treated with either free clofazimine (F-CLF), L-CLF, or empty liposomes twice a week for five treatments beginning on day 1 (acute), day 21 (established), or day 90 (chronic) postinfection. One day after the last treatment, the numbers of CFU of M. tuberculosis in the spleen, liver, and lungs were determined. F-CLF at the maximum tolerated dose of 5 mg/kg of body weight was ineffective; however, 10-fold-higher doses of L-CLF demonstrated a dose response with significant CFU reduction in all tissues without any toxic effects. In acutely infected mice, 50 mg of L-CLF/kg reduced CFU 2 to 3 log units in all three organs. In established or chronic infection, treated mice showed no detectable CFU in the spleen or liver and 1- to 2-log-unit reduction in the lungs. A second series of L-CLF treatments cleared M. tuberculosis in all three tissues. L-CLF appears to be bactericidal in the liver and spleen, which remained negative for M. tuberculosis growth for 2 months. Thus, L-CLF could be useful in the treatment of tuberculosis.

Comparison of the roles of reactive oxygen and nitrogen intermediates in the host response to Mycobacterium tuberculosis using transgenic mice

OBJECTIVE

To study the role of reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI) in host response to Mycobacterium tuberculosis.

DESIGN

M. tuberculosis infection (i.v.) was compared in B6 control and two strains of knockout (KO) mice. X-CGD mice with a nonfunctional allele for the gp91phox subunit of the phagocyte oxidase cytochrome b are unable to produce ROI whereas iNOS KO mice lack a functional inducible nitric oxide synthase (iNOS) gene and fail to make RNI.

RESULTS

M. tuberculosis growth was markedly enhanced in the lungs of X-CGD mice compared to B6 mice, but was controlled in the spleen and liver. In iNOS KO mice, M. tuberculosis growth was exacerbated in the spleen, but was unremarkable in the lungs compared to B6 mice until later (Day 60) in the infection. In vitro, X-CGD alveolar and peritoneal macrophages (M phi) produced no ROI, but did produce RNI and inhibited growth of M. tuberculosis when activated with interferon gamma. iNOS KO M phi produced ROI, but failed to produce RNI and could not cope with M. tuberculosis in vitro when activated. The inhibition of M. tuberculosis growth observed in activated B6 and X-CGD M phi) was reversed in the presence of aminoguanidine.

CONCLUSION

These KO mouse strains demonstrate the relative potent effects of ROI and RNI in resistance to M. tuberculosis and should prove useful for the study of regulatory and compensatory mechanisms of immunity.

An overview of adolescent eating behavior barriers to implementing dietary guidelines

Adolescents continue to report food and nutrient intake and physical activity levels that conflict with the U.S. Dietary Guidelines and the Year 2000 objectives. Some of the barriers to healthier eating and exercise are related to factors within the adolescent's environment, such as access to healthy food choices or availability of preventive nutritional guidance as part of routine health care. Many barriers, though, fit into the theoretical framework that attempts to describe determinants of other risky behaviors of adolescents. These include (1) adolescent and peer subgroup norms that devalue healthy eating behavior; (2) participation in other risky behaviors; (3) low competency (actual and perceived) in sports, food selection, and food preparation; and (4) familial and cultural expectations. Implications were discussed for intervention approaches and policy recommendations that help confront these barriers.

Effects of essential fatty acid deficiency on prostaglandin E2 production and cell-mediated immunity in a mouse model of leprosy

Results from animal and in vitro studies suggest that essential fatty acid (EFA) deficiency enhances cell-mediated immunity by reducing production of prostaglandins with immunosuppressive actions. However, direct experimental evidence that EFA deficiency enhances T-lymphocyte function in vivo has not been obtained. In this study, athymic (nu/nu) mice were infected in the footpads with Mycobacterium leprae and fed a linoleic acid-free diet. These mice, and infected nu/nu mice on control diets, were given an adoptive transfer of M. leprae-primed, T-cell-enriched lymphocytes. After 2 weeks, M. leprae bacilli were harvested from the recipient mice and bacterial viability was determined by the BACTEC system. M. leprae recovered from recipient mice fed control diets displayed little reduction in metabolic activity. In contrast, M. leprae from recipient mice fed the EFA-deficient (EFAD) diet exhibited markedly reduced viability. In vitro, donor cells from M. leprae-primed mice secreted elevated levels of gamma interferon upon exposure to the bacilli. These cells also exhibited an enhanced proliferative response, which was reduced by exogenous prostaglandin E2 (PGE2). In addition, M. leprae-infected granuloma macrophages (Mphi) from EFAD recipient nu/nu mice secreted significantly less PGE2 than granuloma Mphi from mice on control diets. These data suggest that enhanced levels of Mphi-generated PGE2, induced by M. leprae or its constituents, could act as an endogenous negative modulator of the immune response occurring in the microenvironment of the lepromatous granuloma.

Antimycobacterial cycloartanes from Borrichia frutescens

In a bioassay-guided search for antimycobacterial compounds from higher plants of the southeastern United States, we have chemically investigated the sea daisy (Borrichia frutescens) from coastal marshes of Louisiana for their active constituents. Bioactive chromatographic fractions provided two new triterpenes, (24R)-24,25-epoxycycloartan-3-one (1) and (23R)-3-oxolanosta-8,24-dien-23-ol (4), and (3 alpha H, 24R)-24,25-epoxycycloartan-3-ol (3a). Compound 3a had been previously isolated as a mixture of C-24 epimers. The structures of 1, 3a, and 4 were established by spectroscopic methods and chemical transformations, and the molecular structures of 1 and 4 were determined by single-crystal X-ray diffraction. In a radiorespirometric bioassay against Mycobacterium tuberculosis, the epoxycycloartanes 1 and 3a exhibited minimum inhibitory concentrations of 8 micrograms/mL. In contrast, the lanostadiene-type triterpene 4 showed no significant inhibition at 128 micrograms/mL, as did the acetate 3b. Cytotoxicity for Vero cells gave IC50 values of 71.8, 39.8, and 103.6 micrograms/mL for triterpenes 1, 3a, and 4, respectively.

Granulomas Induced by Mycobacterium leprae

Leprosy, a chronic infectious disease caused by Mycobacterium leprae, affects primarily the skin, mucous membranes, and peripheral nerves. It is characterized by a spectrum of symptoms, largely a result of the immunological response of the host to the antigens of M. leprae. At one pole [lepromatous leprosy (LL)] there is an enormous growth of the bacilli in the tissues resulting from a specific and profound lack of cell-mediated immunity (CMI) of the host to M. leprae. At the opposite pole [tuberculoid leprosy (TT)], patients are responsive to M. leprae antigens, and there are few bacilli present in the lesions. A variety of techniques have been applied in the analyses of leprosy granulomas, from standard histological examination to molecular immunological probes. Each technique provides a limited, yet distinctive, look into the constitution of the granuloma. Together, they offer a comprehensive view into the regulation of leprosy granuloma development.

Exacerbation of acute and chronic murine tuberculosis by administration of a tumor necrosis factor receptor-expressing adenovirus

Tumor necrosis factor (TNF) plays a pivotal role in inflammatory phenomena that culminate in either pathogenesis or resistance in mycobacterial disease. The regulatory role of TNF in murine tuberculosis was examined by administering a recombinant adenovirus encoding a fusion protein consisting of the human 55-kDa TNF receptor extracellular domain and the mouse IgG heavy chain domain (AdTNFR). During acute infections with Mycobacterium tuberculosis, AdTNFR pretreatment induced elevated mycobacterial burdens of 1 log10 in the tissues of H37Ra-infected mice and 2 log10 (spleen and liver) and 4 log10 (lungs) in H37Rv-infected mice. In mice infected chronically with H37Rv, AdTNFR treatment induced a 3-log10 increase of M. tuberculosis in the lungs, in which a tuberculous bronchopneumonia developed with numerous acid-fast bacilli visible in alveoli and bronchi. Administration of AdTNFR may serve as a useful model for studying the pathogenesis and chemotherapy of progressive primary tuberculosis.

Regulation of murine macrophage effector functions by lipoarabinomannan from mycobacterial strains with different degrees of virulence

Lipoarabinomannan (LAM) is the major arabinose- and mannose-containing phosphorylated lipopolysaccharide (LPS) in mycobacterial cell walls. LAM preparations from a virulent strain (Erdman) (LAM(Erdman)) and an attenuated strain (H37Ra) (LAMH37Ra) of Mycobacterium tuberculosis, as well as from M. leprae (a virulent mycobacterium), were analyzed for their effects on various macrophage (M phi) effector functions. LAMH37Ra, like gram-negative LPS, exhibited a dose-dependent ability to induce tumor necrosis factor alpha (TNF-alpha) production in normal M phi, and gamma interferon (IFN-gamma) priming of the M phi greatly augmented the levels of TNF-alpha. However, the effects of LAMH37Ra were unaffected by polymyxin B, which totally abrogated the effects of LPS. LAM(Erdman) and LAM from M. leprae, on the other hand, induced virtually no TNF-alpha production. Analysis of M phi mRNA by reverse transcription-polymerase chain reaction revealed that the levels of production. Analysis of M phi mRNA by reverse transcription-polymerase chain reaction revealed that the levels of TNF-alpha mRNA induced by the various preparations correlated with the levels of TNF-alpha protein detected. Interestingly, both LAMH37Ra and LAM(Erdman) could block subsequent IFN-gamma- and LPS-induced M phi activation, a previously reported measure of the potent ability of LAM to down-regulate M phi effector functions. Two lines of evidence suggested, however, that M phi cyclooxygenase products did not play a role in this down-regulation. LAMH37Ra and LPS could induce the production of NO2- in both normal and IFN-gamma-primed M phi, whereas LAM(Erdman) could stimulate NO2- production only in primed M phi. Both LAMH37Ra and LAM(Erdman) could substitute for LPS as a triggering signal for IFN-gamma-primed M phi in a toxoplasma killing assay. The triggering ability of LAM(Erdman), however, was abrogated by an anti-TNF-alpha antibody, suggesting that sufficient TNF-alpha production was stimulated by LAM(Erdman) to drive a M phi function relevant in host resistance. Thus, mycobacterial LAM is a potent regulator of M phi functions, a fact that may have important consequences in mycobacterial disease.