The Prion Basis of Progressive Neurodegenerative Disorders.

The discovery of proteinaceous infectious agents by Prusiner in 1982 was sensational. All previously known pathogens contained nucleic acids, the code of life, that enabled them to reproduce. In contrast, the proteinaceous agents of disease, called prion proteins (PrP), lacked nucleic acids and propagated by binding to the functional, endogenous form of cellular prion protein (referred to as PrP) and altering its conformation to produce the infectious disease-causing misfolded protein (referred to as PrP).

Glyphosate in house dust and risk of childhood acute lymphoblastic leukemia in California.

Background: Residential use of pesticides has been associated with increased risk of childhood acute lymphoblastic leukemia (ALL). We evaluated determinants of glyphosate concentrations in house dust and estimated ALL risk in the California Childhood Leukemia Study (CCLS).

Methods: The CCLS is a population-based case-control study of childhood leukemia in California.

Pesticide exposure in New Zealand school-aged children: Urinary concentrations of biomarkers and assessment of determinants.

This study aimed to assess pesticide exposure and its determinants in children aged 5-14 years. Urine samples (n = 953) were collected from 501 participating children living in urban areas (participant n = 300), rural areas but not on a farm (n = 76), and living on a farm (n = 125). The majority provided two samples, one in the high and one in the low spraying season.

Residential exposure to carbamate, organophosphate, and pyrethroid insecticides in house dust and risk of childhood acute lymphoblastic leukemia.

Background: Self-reported residential use of pesticides has consistently been associated with increased risk of childhood leukemia. However, these studies were limited in their ability to identify specific insecticide active ingredients that were associated with risk.

Objective: We used household carpet dust measurements of 20 insecticides (two carbamate, 10 organophosphate, two organochlorine, and six pyrethroid) as indicators of exposure and evaluated associations with the risk of childhood acute lymphoblastic leukemia (ALL).

Breastmilk, Stool, and Meconium: Bacterial Communities in South Africa.

Human milk optimizes gut microbial richness and diversity, and is critical for proper immune development. Research has shown differing microbial composition based on geographic location, providing evidence that diverse biospecimen data is needed when studying human bacterial communities. Yet, limited research describes human milk and infant gut microbial communities in Africa.

Microalgae-blend tilapia feed eliminates fishmeal and fish oil, improves growth, and is cost viable.

Aquafeed manufacturers have reduced, but not fully eliminated, fishmeal and fish oil and are seeking cost competitive replacements. We combined two commercially available microalgae, to produce a high-performing fish-free feed for Nile tilapia (Oreochromis niloticus)-the world's second largest group of farmed fish. We substituted protein-rich defatted biomass of Nannochloropsis oculata (leftover after oil extraction for nutraceuticals) for fishmeal and whole cells of docosahexaenoic acid (DHA)-rich Schizochytrium sp.

A community-based education programme to reduce insecticide exposure from indoor residual spraying in Limpopo, South Africa.

Background: Indoor residual spraying (IRS), the coating of interior walls of houses with insecticides, is common in malaria-endemic areas. While important in malaria control, IRS potentially exposes residents to harmful insecticides. The World Health Organization recommends steps to minimize exposure; however, no programme has focused on educating populations.

Determinants of pesticide concentrations in silicone wristbands worn by Latina adolescent girls in a California farmworker community: The COSECHA youth participatory action study.

Personal exposure to pesticides has not been well characterized, especially among adolescents. We used silicone wristbands to assess pesticide exposure in 14 to 16 year old Latina girls (N = 97) living in the agricultural Salinas Valley, California, USA and enrolled in the COSECHA (CHAMACOS of Salinas Examining Chemicals in Homes and Agriculture) Study, a youth participatory action study in an agricultural region of California. We determined pesticide concentrations (ng/g/day) in silicone wristbands worn for one week using gas chromatography electron capture detection and employed gas chromatography mass spectrometry to determine the presence or absence of over 1500 chemicals.

Association between prenatal exposure to multiple insecticides and child body weight and body composition in the VHEMBE South African birth cohort.

Background: Pregnant women may be co-exposed to multiple insecticides in regions where both pyrethroids and dichlorodiphenyltrichloroethane (DDT) are used for indoor residual spraying (IRS) for malaria control. Despite the potential for adverse effects on offspring, there are few studies in areas where IRS is currently used and little is known about the effects of pyrethroids on children's health.

Methods: We investigated the relationship between concentrations of four urinary pyrethroid metabolites in urine and organochlorine pesticide concentrations in maternal blood collected near delivery on body weight and body composition among children ≤2 years old participating in the prospective South Africa VHEMBE birth cohort (N = 708).

Maternal Depression and Childhood Overweight in the CHAMACOS Study of Mexican-American Children.

Objective Although previous studies have examined the impact of maternal depression on child overweight and obesity, little is known about the relationship in Latino families, who suffer from high risks of depression and obesity. We prospectively investigated the association between depressive symptoms in women with young children and child overweight and obesity (overweight/obesity) at age 7 years among Latino families. Methods Participants included 332 singletons with anthropometric measures obtained at 7 years from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, a birth cohort study.

Maternal blood and hair manganese concentrations, fetal growth, and length of gestation in the ISA cohort in Costa Rica.

Background: Animal studies have shown that both deficiency and excess manganese (Mn) may result in decreased fetal size and weight, but human studies have reported inconsistent results.

Methods: We examined the association of blood and hair Mn concentrations measured at different times during pregnancy with fetal growth among term births and length of gestation in a cohort of 380 mother-infant pairs living near banana plantations aerially sprayed with Mn-containing fungicides in Costa Rica. We used linear regression and generalized additive models to test for linear and nonlinear associations

Results: Mean (± SD) blood Mn concentration was 24.

Acceptability of health information technology aimed at environmental health education in a prenatal clinic.

Objective: To describe the acceptability of an interactive computer kiosk that provides environmental health education to low-income Latina prenatal patients.

Methods: A mixed-methods approach was used to assess the acceptability of the Prenatal Environmental Health Kiosk pregnant Latina women in Salinas, CA (n=152). The kiosk is a low literacy, interactive touch-screen computer program with an audio component and includes graphics and an interactive game.

mSpray: a mobile phone technology to improve malaria control efforts and monitor human exposure to malaria control pesticides in Limpopo, South Africa.

Recent estimates indicate that malaria has led to over half a million deaths worldwide, mostly to African children. Indoor residual spraying (IRS) of insecticides is one of the primary vector control interventions. However, current reporting systems do not obtain precise location of IRS events in relation to malaria cases, which poses challenges for effective and efficient malaria control.

Prenatal and early childhood bisphenol A concentrations and behavior in school-aged children.

Introduction: Early life exposure to bisphenol A (BPA), an endocrine disrupting chemical used in some food and beverage containers, receipts, and dental sealants, has been associated with anxiety and hyperactivity in animal studies. A few human studies also show prenatal and childhood BPA exposure to be associated with behavior problems in children.

Methods: We measured BPA in urine from mothers during pregnancy and children at 5 years of age (N=292).

Genetic variants in ARID5B and CEBPE are childhood ALL susceptibility loci in Hispanics.

Recent genome-wide studies conducted in European Whites have identified novel susceptibility genes for childhood acute lymphoblastic leukemia (ALL). We sought to examine whether these loci are susceptibility genes among Hispanics, whose reported incidence of childhood ALL is the highest of all ethnic groups in California, and whether their effects differ between Hispanics and non-Hispanic Whites (NHWs). We genotyped 13 variants in these genes among 706 Hispanic (300 cases, 406 controls) and 594 NHW (225 cases, 369 controls) participants in a matched population-based case-control study in California.

Determinants of urinary bisphenol A concentrations in Mexican/Mexican--American pregnant women.

Prenatal exposure to bisphenol A (BPA) may be associated with adverse health effects in the developing fetus; however, little is known about predictors of BPA exposure during pregnancy. We examined BPA exposure in 491 pregnant women from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) cohort and explored the role of living in the United States on significant dietary predictors of BPA exposure. Women provided urine samples up to two times during pregnancy (n=866 total samples).

The Relationship between Neighborhood Characteristics and Effective Parenting Behaviors: The Role of Social Support.

Neighborhood characteristics have been linked to healthy behavior, including effective parenting behaviors. This may be partially explained through the neighborhood's relation to parents' access to social support from friends and family. The current study examined associations of neighborhood characteristics with parenting behaviors indirectly through social support.

Exploring the Spread of Methamphetamine Problems within California, 1980 to 2006.

Background: The introduction and spread of high potency methamphetamine has led to dramatic increases in drug-related problems in California. Prior research suggests that drug abuse rates are related to local demographic and economic characteristics, law enforcement activities, and sentencing practices. Methamphetamine abuse in particular has been shown to be reduced by laws regulating the raw materials needed for its production.

Geospatial Analyses of Alcohol and Drug Problems: Empirical Needs and Theoretical Foundations.

Over the past four decades geospatial analyses of alcohol and drug problems have moved to the forefront of ecological studies of the correlates and determinants of drug addictions in community health. These advances have been predicated upon the expanding computational capabilities of geographic information systems, advancement of statistical tools for the analysis of spatial data, and the formulation of suitable social ecological theory. This paper provides an introduction to the study of drug markets in the US as a model social problem for geospatial research and analysis.

Intimate partner violence among adolescents in Cape Town, South Africa.

This study aimed to describe potentially preventable factors in intimate partner violence (IPV) perpetration and victimization among South African 8th grade students. Data were collected during a pilot evaluation of a classroom 8th grade curriculum on gender-based violence prevention in nine public schools in Cape Town through self-completed interviews with 549 8th grade students, 238 boys and 311 girls. Structural equation models (SEM) predicting IPV were constructed with variables a priori hypothesized to be associated.

Blood levels of folate at birth and risk of childhood leukemia.

Background: A role for folate in cancer etiology has long been suspected because of folate's function as a cofactor in DNA methylation and maintenance of DNA synthesis. Previous case-control studies examining the association between risk of childhood acute lymphoblastic leukemia (ALL) and mothers' self-reported folate intake and supplementation have been inconclusive.

Materials And Methods: We used a quantitative microbiologic assay to measure newborn folate concentrations in archived dried bloodspots collected at birth from 313 incident ALL cases, 44 incident acute myeloid leukemia (AML) cases, and 405 matched population-based controls.

Parental Strategies for Knowledge of Adolescents' Friends: Distinct from Monitoring?

Parental monitoring is defined as a set of behaviors used to gain knowledge about an adolescent's whereabouts, friends and associates, and activities. However, can knowledge of adolescents' whereabouts/activities, and friends all be attained through the same strategies? Or do they require their own strategies? This study used qualitative interviews with 173 parents of older adolescents from 100 families. Emergent themes described strategies by which parents gain information about their adolescents' friends and the substance use of those friends.

Alcohol Policy Comprehension, Compliance and Consequences Among Young Adult Restaurant Workers.

This study explores relationships between young adult restaurant employees' understanding and compliance with workplace alcohol control policies and consequences of alcohol policy violation. A mixed method analysis of 67 semi-structured interviews and 1,294 telephone surveys from restaurant chain employees found that alcohol policy details confused roughly a third of employees. Among current drinkers (n=1,093), multivariable linear regression analysis found that frequency of alcohol policy violation was positively associated with frequency of experiencing problems at work; perceived supervisor enforcement of alcohol policy was negatively associated with this outcome.

Variation in xenobiotic transport and metabolism genes, household chemical exposures, and risk of childhood acute lymphoblastic leukemia.

Background: Recent studies suggest that environmental exposures to pesticides, tobacco, and other xenobiotic chemicals may increase risk of childhood acute lymphoblastic leukemia (ALL). We sought to evaluate the role of genes involved in xenobiotic transport and metabolism in childhood ALL risk, both alone and in conjunction with household chemical exposures previously found to be associated with childhood ALL risk.

Methods: We conducted a population-based epidemiologic study of 377 cases and 448 controls in California, utilizing a haplotype-based approach to evaluate 42 xenobiotic transport and metabolism genes in conjunction with data on self-reported household chemical exposures.