Derivation and application of indoor air screening values for inhalation exposure to semi-volatile organic compounds.

Semi-volatile organic compounds (SVOCs) are being increasingly studied in indoor air. The absence of health-based inhalation exposure guidelines for most SVOCs impedes the interpretation of indoor air concentrations from a health risk context. To accelerate the derivation of screening values for a large number of SVOCs, a tiered framework was developed to evaluate and adjust published hazard assessments for SVOCs to calculate benchmarks relevant for evaluation of inhalation risk. Inhalation screening values were derived for 43 SVOCs considered in this study, most of which required extrapolation from oral exposure guidelines. The screening values were compared to published SVOC concentrations in homes in Canada to evaluate the potential health risks of chronic exposure to SVOCs in indoor residential environments. SVOCs that could be prioritized for further evaluation were dibutyl phthalates (DBP), di(2-ethylhexyl) phthalate (DEHP) and polybrominated diphenyl ethers (PBDEs). The framework could be applied more broadly in the future to derive screening values for other non-traditional indoor air contaminants with limited inhalation hazard data or assessments.

Development of the Urinary Tract in Fetal Rats: A Micro-CT Study.

INTRODUCTION: Micro-computed tomography (micro-CT) is an established tool to study fetal development in rodents. This study aimed to use micro-CT imaging to visualize the development of the urinary tract in fetal rats. MATERIALS AND METHODS: Fetal rats from embryonic day (ED) 15, ED17, ED19, ED21, and N0 (newborn) (n = 6 per group; 3 males) were fixed and desiccated using the "critical point" technique. We utilized the micro-CT system (SkyScan) and analyzed the resulting scans with CTAn, DataViewer, and ImageJ to visualize the morphology and quantify the volumes of kidney, bladder, adrenal gland, as well as length of the ureter. RESULTS: High-resolution micro-CT showed continuous growth of both kidneys from ED15 to N0, with the highest increase between ED19 and ED21. The length of the ureter increased from ED15 to ED21 and remained stable until birth. The volume of the bladder steadily increased from ED15 to N0.In females, a statistically higher volume of the adrenal gland on ED21 was observed, whereas no sex-specific differences were seen for kidney, ureter, and bladder development. CONCLUSION: Micro-CT depicts an excellent tool to study urinary tract development in the fetal and neonatal rat. It enables the metric quantification of longitudinal anatomic changes in high definition without previous destructive tissue preparation. The present study revealed sex-specific differences of the adrenal gland development and provides comprehensive data for the understanding of fetal urinary tract development, inspiring future research on congenital urological malformations.

Assessment of feasibility and outcomes of a salivary cortisol collection protocol in five American Indian communities.

We evaluated the feasibility and outcomes of administering a naturalistic saliva collection procedure and assessment in American Indian (Indigenous) communities. We focus on Indigenous adults living with type 2 diabetes given the "epidemic" of the disease disproportionately impacting many tribal groups. Data are from community-based participatory research (CBPR) involving 5 tribal communities. Participants were randomly selected from tribal clinic records. The sample includes 188 adults living with type 2 diabetes (56% female; age range = 18-77 years; M age = 46.3 years). Participants provided a total of 748 saliva samples, representing 4 samples/participant on a single day with instructions for collection at 4 time points: upon waking, 1 h after waking, 2 h after waking, and at 8 PM. Saliva sample times were recorded by participants on paper and electronically via placement in a Medication Event Monitoring System (MEMS®) bottle. Overall, 67% of samples were completed within 10 min of protocol instructions and 91% of participants provided at least one useable sample (79% provided four useable samples). Noncompliance, behavioral and environmental factors were not robustly associated with deviations in observed cortisol indices. Results suggest that home-based, community interviewer-involved protocols yields valid data with high compliance. The success of this study was facilitated by exemplary efforts of tribal community-based interviewers and our overall CBPR approach.Lay summaryAuthentic efforts for tribal community partnerships in research are critical to successfully implementing biological assessments with American Indians given legacies of research misconduct and mistrustOur Community-Based Participatory Research with 5 tribes yielded high participant compliance to a home-based salivary cortisol collection protocolLack of compliance to salivary cortisol protocol and medication usage were not consistently associated with observed cortisol indices.

Patient-Centered Care, Diabetes Empowerment, and Type 2 Diabetes Medication Adherence Among American Indian Patients.

IN BRIEF Type 2 diabetes has been labeled an epidemic in many American Indian communities. Thus, identifying factors that improve medication adherence for American Indian patients is crucial. We found significant and positive relationships among patient-centered care, medication adherence, and diabetes empowerment. In addition, diabetes empowerment partially mediated the relationship between patient-centered care and medication adherence.

Barriers to Healthcare for American Indians Experiencing Homelessness.

Members of American Indian (AI) communities face many barriers to receiving both mental and physical healthcare. These barriers can have a negative effect on overall health. Barriers are compounded for AIs who are also experiencing homelessness, and AI make up a disproportionate percentage of the homeless population nationwide. In-depth semi-structured interviews were conducted with 12 service providers and 16 homeless participants in a mid-size Midwestern city to identify barriers to care for homeless participants. Key barriers identified in this study for homeless participants were: transportation, phone accessibility, discrimination, and cold and bureaucratic cultures of healthcare systems. Major barriers identified by service providers were: access to care, discrimination and mistrust, and restrictive policies. Given generally higher disease prevalence within the homeless population and health disparities within the AI community, steps should be taken to reduce barriers to healthcare.