Faculty Bibliography

Exposure to inorganic arsenic (InAs) via drinking water and/or food is a considerable worldwide problem. Methylation of InAs generates monomethyl (MMAs^III+V)- and dimethyl (DMAs^III+V)-arsenical species in a process that facilitates urinary As elimination; however, MMAs is considerably more toxic than either InAs or DMAs. Emerging evidence suggests that incomplete methylation of As to DMAs, resulting in increased MMAs, is associated with increased risk for a host of As-related health outcomes. The biochemical pathway that provides methyl groups for As methylation, one-carbon metabolism (OCM), is influenced by folate and other micronutrients, including choline and betaine. Individuals and species differ widely in their ability to methylate As. A growing body of research, including cell-culture, animal-model, and epidemiological studies, has demonstrated the role of OCM-related micronutrients in As methylation. This review examines the evidence that nutritional status and nutritional interventions can influence the metabolism and toxicity of As, with a primary focus on folate.

Prenatal arsenic exposure is associated with adverse birth outcomes and disease risk later in life, which could be mediated through epigenetic dysregulation. We evaluated the association between arsenic and gestational age (GA) that was mediated through DNA methylation (DNAm) using data from a Bangladeshi birth cohort. Arsenic exposure was measured in maternal drinking water at ≤16 weeks GA and maternal toenails collected ≤1 month postpartum. Cord blood DNAm was measured using Infinium HumanMethylation450 arrays (n = 44, discovery phase). Top loci identified in the discovery phase were then pyrosequenced in a second group (n = 569, validation phase). Structural equation models (SEM) evaluated the direct and indirect effects of arsenic and DNAm on GA. In the discovery phase, arsenic was associated with differential DNAm of 139 loci that were associated with GA (P < 1.10X10^-6; |β regression|>0.10). Each doubling in water arsenic concentration decreased GA by 2 days, which was fully mediated through the main principal component of the top-ten CpGs (P < 0.001). In the validation phase, there were direct and indirect effects of miR214-3 and MCC DNAm on GA. In an adjusted SEM model, mediation of the association between arsenic and GA by miR124-3 was borderline significant (P = 0.061). This study therefore identified DNAm at specific loci in cord blood that mediated the effect of arsenic exposure on GA. Specifically, prenatal arsenic exposure was associated with lower methylation of miR124-3 that mediated the exposure-response of arsenic on GA. Future research should evaluate if these epigenetic changes are persistent and associated with disease risk.

OBJECTIVE/UNASSIGNED:are considered as potential moderators. DESIGN/UNASSIGNED:age = 4.43 years). Parent and teacher assessments of child internalizing and externalizing were also collected at baseline and 12 months later. RESULTS/UNASSIGNED:At Time 1, male child gender was positively correlated with concurrent spanking; familial social support and U.S. American cultural knowledge were negatively correlated with mothers' spanking. Verbal punishment at Time 1 was associated with externalizing problems at Time 2 among both Mexican and Dominican American children, and this relation was not moderated. Additionally, verbal punishment was associated with Time 2 child internalizing problems among Mexican American children. There were no significant associations between spanking and later child internalizing or externalizing behaviors. CONCLUSION/UNASSIGNED:It is important that researchers examine both physical and verbal discipline strategies to understand their unique influences on Latino child outcomes, as well as contextual influences that may elucidate the use and long-term effects of spanking and verbal punishment on Latino children at different developmental stages.

Early academic achievement has been shown to predict high school completion, but there have been few studies of the predictors of early academic success focused on Latino students. Using longitudinal data from 750 Mexican and Dominican American families, this study examined a cultural model of parenting and early academic achievement. While Latino students were achieving in the average range as a whole, certain subgroups (e.g., Dominicans, boys) were at higher risk for underachievement. Results highlighted the protective role of authoritative parenting, which was associated with academic and social-emotional school readiness, both of which predicted higher achievement at the end of first grade. The role of respeto and authoritarian parenting practices in academic achievement at first grade differed between Mexican and Dominican American families. Findings advance understanding of early achievement and parenting among Latino families from a cultural perspective.

BACKGROUND:Adolescent pregnancies within urban resource-deprived settlements predispose young girls to adverse mental health and psychosocial adversities, notably depression. Depression in sub-Saharan Africa is a leading contributor to years lived with disability (YLD). The study's objective was to determine the prevalence of depression and related psychosocial risks among pregnant adolescents reporting at a maternal and child health clinic in Nairobi, Kenya. METHODS:A convenient sample of 176 pregnant adolescents attending antenatal clinic in Kangemi primary healthcare health facility participated in the study. We used PHQ-9 to assess prevalence of depression. Hierarchical multivariate linear regression was performed to determine the independent predictors of depression from the psychosocial factors that were significantly associated with depression at the univariate analyses. RESULTS:Of the 176 pregnant adolescents between ages 15-18 years sampled in the study, 32.9% (n = 58) tested positive for a depression diagnosis using PHQ-9 using a cut-off score of 15+. However on multivariate linear regression, after various iterations, when individual predictors using standardized beta scores were examined, having experienced a stressful life event (B = 3.27, P = 0.001, β =0.25) explained the most variance in the care giver burden, followed by absence of social support for pregnant adolescents (B = - 2.76, P = 0.008, β = - 0.19), being diagnosed with HIV/AIDS (B = 3.81, P = 0.004, β =0.17) and being young (B = 2.46, P = 0.038, β =0.14). CONCLUSION:Depression is common among pregnant adolescents in urban resource-deprived areas of Kenya and is correlated with well-documented risk factors such as being of a younger age and being HIV positive. Interventions aimed at reducing or preventing depression in this population should target these groups and provide support to those experiencing greatest stress.

BACKGROUND:Mental illness affects every segment of population including young adults. The beliefs held by young patients regarding the causes of mental illness impact their treatment-seeking behaviour. It is pertinent to know the commonly held attributions around mental illness so as to effectively provide psychological care, especially in a resource constrained context such as Kenya. This helps in targeting services around issues such as stigma and extending youth-friendly services. METHODS:Guided by the private theories interview (PTI-P) and attributional framework, individual semi-structured interviews were carried out with ten young adults of ages 18-25 years about their mental health condition for which they were undergoing treatment. Each interview took 30-45 min. We mapped four attributions (locus of control, stability, controllability and stigma) on PTI-P questions. Data was transcribed verbatim to produce transcripts coded using interpretive phenomenological analysis. These codes were then broken down into categories that could be used to understand various attributions. RESULTS:We found PTI-P to be a useful tool and it elicited three key themes: (a) psychosocial triggers of distress (with themes of negative thoughts, emotions around mental health stigma and negative childhood experiences, parents' separation or divorce, death of a loved one etc.), (b) biological conditions and psychopathologies limiting intervention, and (c) preferences and views on treatment. Mapping these themes on our attributional framework, PTI-P themes presented as causal attributions explaining stigma, locus of control dimensions and stability. External factors were mainly ascribed to be the cause of unstable and uncontrollable attributions including persistent negative emotions and thoughts further exacerbating psychological distress. Nine out of the ten participants expressed the need for more intense and supportive therapy. CONCLUSION/CONCLUSIONS:Our study has provided some experiential evidence in understanding how stigma, internal vs external locus of control, stability vs instability attributions play a role in shaping attitudes young people have towards their mental health. Our study points to psychosocial challenges such as stigma, poverty and lack of social support that continue to undermine mental well-being of Kenyan youth. These factors need to be considered when addressing mental health needs of young people in Kenya.

BACKGROUND:Globally adolescents continue to have an upward trend in HIV incidence and AIDS-related mortality. The interplay between the rapid physical growth, sexual maturation, and enormous albeit slow-evolving cognitive and psychological changes in adolescence may partly explain this trend. Our main purpose was to highlight key psychosocial characteristics of HIV-infected adolescents and explore if these characteristics are associated with depression symptoms. METHODS:From August to December 2016 after obtaining informed consent, adolescents living with HIV at Kenyatta National Hospital were interviewed using the Home environment, Education and Employment, Activity, Sexuality, Suicide and depression traits (HEADSS) tool combined with the Patient Health Questionnaire (PHQ-9) to elucidate which key symptoms of depression and link with psychosocial characteristics mapped on HEADSS. In order to determine which psychosocial characteristics were linked with risk of depression, the traits of adolescents who were symptomatic were compared to those who were not using univariate and multivariate regression analysis. RESULTS: = 0.06]. CONCLUSION/CONCLUSIONS:One in two of the adolescents interviewed had depression symptoms which were significantly associated with lack of school fees, missing meals, non-adherence to medication, and substance abuse.

Approximately, 42% of the Kenyan population live below the poverty line. Rapid growth and urbanization of Kenya's population have resulted in a changing poverty and food security environment in high-density urban areas. Lack of basic food needs in Kenya affects approximately 34.8% rural population and 7.6% of its urban population. Using multi-community stakeholders such as teachers and community health workers (CHWs), this paper examined food insecurity and its consequences on caregiving practices and child development. A qualitative study design was utilized. Key informant interviews and focused-group discussions with four primary school teachers and three CHWs and a nurse in-charge working within Kariobangi and Kangemi were applied to elicit various perspectives from family-, school- and community-level challenges that influence caregiving practices and child development. Grounded theory method was applied for qualitative data sifting and thematic analysis. Our findings exposed various challenges at the school, family and the community levels that affect caregiving practices and consequent child development. School-level challenges included lack of adequate amenities for effective learning, food insecurity, absenteeism and mental health challenges. Family-level barriers included lack of parenting skills, financial constraints, domestic violence and lack of social support, while community challenges such as unemployment, poor living conditions, cultural practices, lack of social support and poor community follow-up mechanisms contributed to poor parenting practices and child development. Parenting practices and holistic child development strategies in resource poor settings should focus on parenting skills, food security, quality education and addressing parents and children's mental health challenges.