Environmental chemical-wide associations with immune biomarkers in US adults: A cross-sectional analysis.

Environmental chemical exposures influence immune system functions, and humans are exposed to a wide range of chemicals, termed the chemical "exposome". A comprehensive, discovery analysis of the associations of multiple chemical families with immune biomarkers is needed. In this study, we tested the associations between environmental chemical concentrations and immune biomarkers. We analyzed the United States cross-sectional National Health and Nutrition Examination Survey (NHANES, 1999-2018). Chemical biomarker concentrations were measured in blood or urine (196 chemicals, 17 chemical families). Immune biomarkers included counts of lymphocytes, neutrophils, monocytes, basophils, eosinophils, red blood cells, white blood cells, and mean corpuscular volume. We conducted separate survey-weighted, multivariable linear regressions of each log2-transformed chemical and immune measure, adjusted for relevant covariates. We accounted for multiple comparisons using a false discovery rate (FDR). Among 45,528 adult participants, the mean age was 45.7 years, 51.4% were female, and 69.3% were Non-Hispanic White. 71 (36.2%) chemicals were associated with at least one of the eight immune biomarkers. The most chemical associations (FDR<0.05) were observed with mean corpuscular volume (36 chemicals) and red blood cell counts (35 chemicals). For example, a doubling in the concentration of cotinine was associated with 0.16 fL (95% CI: 0.15, 0.17; FDR<0.001) increased mean corpuscular volume, and a doubling in the concentration of blood lead was associated with 61,736 increased red blood cells per µL (95% CI: 54,335, 69,138; FDR<0.001). A wide variety of chemicals, such as metals and smoking-related compounds, were highly associated with immune system biomarkers. This environmental chemical-wide association study identified chemicals from multiple families for further toxicological, immunologic, and epidemiological investigation.

Harmonized US National Health and Nutrition Examination Survey 1988-2018 for high throughput exposome-health discovery.

The National Health and Nutrition Examination Survey (NHANES) provides data on the health and environmental exposure of the non-institutionalized US population. Such data have considerable potential to understand how the environment and behaviors impact human health. These data are also currently leveraged to answer public health questions such as prevalence of disease. However, these data need to first be processed before new insights can be derived through large-scale analyses. NHANES data are stored across hundreds of files with multiple inconsistencies. Correcting such inconsistencies takes systematic cross examination and considerable efforts but is required for accurately and reproducibly characterizing the associations between the exposome and diseases. Thus, we developed a set of curated and unified datasets and accompanied code by merging 614 separate files and harmonizing unrestricted data across NHANES III (1988-1994) and Continuous (1999-2018), totaling 134,310 participants and 4,740 variables. The variables convey 1) demographic information, 2) dietary consumption, 3) physical examination results, 4) occupation, 5) questionnaire items (e.g., physical activity, general health status, medical conditions), 6) medications, 7) mortality status linked from the National Death Index, 8) survey weights, 9) environmental exposure biomarker measurements, and 10) chemical comments that indicate which measurements are below or above the lower limit of detection. We also provide a data dictionary listing the variables and their descriptions to help researchers browse the data. We also provide R markdown files to show example codes on calculating summary statistics and running regression models to help accelerate high-throughput analysis and secular trends of the exposome. [Table: see text].

Prenatal vitamin intake in first month of pregnancy and DNA methylation in cord blood and placenta in two prospective cohorts.

BACKGROUND: Prenatal vitamin use is recommended before and during pregnancies for normal fetal development. Prenatal vitamins do not have a standard formulation, but many contain calcium, folic acid, iodine, iron, omega-3 fatty acids, zinc, and vitamins A, B6, B12, and D, and usually they contain higher concentrations of folic acid and iron than regular multivitamins in the US Nutrient levels can impact epigenetic factors such as DNA methylation, but relationships between maternal prenatal vitamin use and DNA methylation have been relatively understudied. We examined use of prenatal vitamins in the first month of pregnancy in relation to cord blood and placenta DNA methylation in two prospective pregnancy cohorts: the Early Autism Risk Longitudinal Investigation (EARLI) and Markers of Autism Risk Learning Early Signs (MARBLES) studies. RESULTS: In placenta, prenatal vitamin intake was marginally associated with -0.52% (95% CI -1.04, 0.01) lower mean array-wide DNA methylation in EARLI, and associated with -0.60% (-1.08, -0.13) lower mean array-wide DNA methylation in MARBLES. There was little consistency in the associations between prenatal vitamin intake and single DNA methylation site effect estimates across cohorts and tissues, with only a few overlapping sites with correlated effect estimates. However, the single DNA methylation sites with p-value < 0.01 (EARLI cord nCpGs = 4068, EARLI placenta nCpGs = 3647, MARBLES cord nCpGs = 4068, MARBLES placenta nCpGs = 9563) were consistently enriched in neuronal developmental pathways. CONCLUSIONS: Together, our findings suggest that prenatal vitamin intake in the first month of pregnancy may be related to lower placental global DNA methylation and related to DNA methylation in brain-related pathways in both placenta and cord blood.

Saliva cell type DNA methylation reference panel for epidemiological studies in children.

Saliva is a widely used biological sample, especially in pediatric research, containing a heterogenous mixture of immune and epithelial cells. Associations of exposure or disease with saliva DNA methylation can be influenced by cell-type proportions. Here, we developed a saliva cell-type DNA methylation reference panel to estimate interindividual cell-type heterogeneity in whole saliva studies. Saliva was collected from 22 children (7-16 years) and sorted into immune and epithelial cells, using size exclusion filtration and magnetic bead sorting. DNA methylation was measured using the Illumina MethylationEPIC BeadChip. We assessed cell-type differences in DNA methylation profiles and tested for enriched biological pathways. Immune and epithelial cells differed at 181,577 (22.8%) DNA methylation sites (t-test p < 6.28 × 10-8). Immune cell hypomethylated sites are mapped to genes enriched for immune pathways (p < 3.2 × 10-5). Epithelial cell hypomethylated sites were enriched for cornification (p = 5.2 × 10-4), a key process for hard palette formation. Saliva immune and epithelial cells have distinct DNA methylation profiles which can drive whole-saliva DNA methylation measures. A primary saliva DNA methylation reference panel, easily implemented with an R package, will allow estimates of cell proportions from whole saliva samples and improve epigenetic epidemiology studies by accounting for measurement heterogeneity by cell-type proportions.

Rapid Neurocognitive Deterioration and Mortality in a Healthcare Professional With Spongiform Encephalopathy: Implications for Neurologic and End-of-Life Care.

Spongiform encephalopathy (SE) is a rare prion disorder characterized by progressive cognitive dysfunction and mortality. Affected patients can observe a wide variety of neurological symptoms, such as myoclonus, dementia, cerebellar signs, and others. We present a case of laboratory-confirmed SE in an otherwise healthy 57-year-old medical professional who initially presented with nonspecific and unique "head in a fish-bowl" dissociation and cognitive decline. No social risk factors were ever identified other than his healthcare career, but subsequent neuroimaging, serology, and lumbar puncture confirmed a diagnosis of sporadic SE due to unknown etiology. He was then treated symptomatically and referred ultimately to palliative care. The patient passed while in hospice care with time from the initial diagnosis to mortality being only 42 days. Given his vague but uniquely rapid deterioration and subsequent mortality, we highlight an opportunity to discuss diagnosis, management, quality improvement, and ethical concerns associated with SE prognosis. We aim to help primary care physicians and neurologists better elucidate the risk factors, signs and symptoms, and pathophysiology of SE to make an early diagnosis. Symptoms can then be managed effectively and palliative services coordinated via a legal and compassionate shared decision-making approach. We recommend that once a diagnosis is made, a discussion with the patient and their family about advance directives and end-of-life care be coordinated as soon as reasonably possible. This should be carried out by a multidisciplinary team consisting of the patient's primary care physician and neurologist, as well as a social worker, palliative care physician, and counselor (spiritual or otherwise). It is our hope that through a better understanding of these factors in SE care, quality of life improvement protocols in similarly-debilitating neurocognitive diseases can be developed.

Medical students as simulation educators: students' experience of a 7-week simulation-based education rotation.

Medical students will have future roles as clinician educators, and need to develop knowledge and skills for that role. Specific skills in simulation-based education (SBE) may be valuable in many educational settings. We aimed to understand the impact of a 7-week placement in SBE on the development of medical students' knowledge, skills and perspectives as educators. We reviewed the experience of three graduated students (also coauthors of this article) who participated in the rotation in 2018. This case study includes analysis of the students' electronic portfolios, rotation reports and subsequent reflections of the student coauthors. Five themes were identified:-'Development as a professional', 'Active participation in an educator team', 'Diverse experience in simulation skills and techniques', 'Role models and mentoring' and 'Rethinking feedback'. Students describe the development of practical knowledge and skills, and more fundamental reflections on the nature of learning, feedback and their personal professional development. We suggest that integration of a simulation education elective within a medical school curriculum helps build capacity for effective SBE delivery, and has positive impacts on students for their future roles as doctors, educators and lifelong learners.

Single-Cell Analysis of the Gene Expression Effects of Developmental Lead (Pb) Exposure on the Mouse Hippocampus.

Lead (Pb) exposure is ubiquitous with permanent neurodevelopmental effects. The hippocampus brain region is involved in learning and memory with heterogeneous cellular composition. The hippocampus cell type-specific responses to Pb are unknown. The objective of this study is to examine perinatal Pb treatment effects on adult hippocampus gene expression, at the level of individual cells. In mice perinatally exposed to control water or a human physiologically relevant level (32 ppm in maternal drinking water) of Pb, 2 weeks prior to mating through weaning, we tested for hippocampus gene expression and cellular differences at 5 months of age. We sequenced RNA from 5258 hippocampal cells to (1) test for treatment gene expression differences averaged across all cells, (2) compare cell cluster composition by treatment, and (3) test for treatment gene expression and pathway differences within cell clusters. Gene expression patterns revealed 12 hippocampus cell clusters, mapping to major expected cell types (eg, microglia, astrocytes, neurons, and oligodendrocytes). Perinatal Pb treatment was associated with 12.4% more oligodendrocytes (p = 4.4 × 10-21) in adult mice. Across all cells, Pb treatment was associated with expression of cell cluster marker genes. Within cell clusters, Pb treatment (q < 0.05) caused differential gene expression in endothelial, microglial, pericyte, and astrocyte cells. Pb treatment upregulated protein folding pathways in microglia (p = 3.4 × 10-9) and stress response in oligodendrocytes (p = 3.2 × 10-5). Bulk tissue analysis may be influenced by changes in cell type composition, obscuring effects within vulnerable cell types. This study serves as a biological reference for future single-cell toxicant studies, to ultimately characterize molecular effects on cognition and behavior.

Relationship between Meditation and Waking Salivary Cortisol Secretion among Long-Term MBSR Instructors.

BACKGROUND: A potential relationship between long-term meditation practice and stress reduction remains virtually unexplored. The purpose of this study was to characterize stress using salivary waking cortisol in a group of long-term meditators with training in the Mindfulness-Based Stress Reduction (MBSR) program. MATERIALS AND METHODS: Four salivary cortisol samples were collected from meditators (n = 84) during the first hour of awakening. The waking cortisol rhythm was summarized using cortisol area under the curve (AUC) with respect to increased secretion above baseline (AUCI) and cortisol AUC above ground (above zero, AUCG); data on meditation duration and depth, perceived stress, and other covariates were collected via self-reported questionnaire. RESULTS: Individuals in the highest quartile of years meditating (> 26 years) had statistically significantly elevated AUCG values (p = 0.01) as compared to individuals in the lowest quartile of years meditating (≤10 years). This relationship was more pronounced among individuals waking at or before 6: 30 a.m. CONCLUSIONS: Overall, an increasing number of years of meditation practice was related to a higher waking cortisol response. These intriguing findings warrant additional exploration, as the stress response can be complex.

Effective and Novel Application of Hydrodynamic Voltammetry to the Study of Superoxide Radical Scavenging by Natural Phenolic Antioxidants.

The reactions of antioxidants with superoxide radical were studied by cyclic voltammetry (CV)-and hydrodynamic voltammetry at a rotating ring-disk electrode (RRDE). In both methods, the superoxide is generated in solution from dissolved oxygen and then measured after being allowed to react with the antioxidant being studied. Both methods detected and measured the radical scavenging but the RRDE was able to give detailed insight into the antioxidant behavior. Three flavonoids, chrysin, quercetin and eriodictyol, were studied, their scavenging activity of superoxide was assessed and the molecular structure of each flavonoid was related to its scavenging capability. From our improved and novel RRDE method, we determine the ability of these 3 antioxidants to react with superoxide radical in a more quantitative manner than the classical CV. Density Functional Theory (DFT) and single crystal X-ray diffraction data provide structural information that assists in clarifying the scavenging molecular mechanism. Hydroxyls associated with the A ring, as found in chrysin, scavenge superoxide in a different manner than those found in the B ring of flavonoids, as those in quercetin and eriodictyol.

Cadmium Exposure Inhibits Branching Morphogenesis and Causes Alterations Consistent With HIF-1α Inhibition in Human Primary Breast Organoids.

Developmental cadmium exposure in vivo disrupts mammary gland differentiation, while exposure of breast cell lines to cadmium causes invasion consistent with the epithelial-mesenchymal transition (EMT). The effects of cadmium on normal human breast stem cells have not been measured. Here, we quantified the effects of cadmium exposure on reduction mammoplasty patient-derived breast stem cell proliferation and differentiation. Using the mammosphere assay and organoid formation in 3D hydrogels, we tested 2 physiologically relevant doses of cadmium, 0.25 and 2.5 µM, and tested for molecular alterations using RNA-seq. We functionally validated our RNA-seq findings with a hypoxia-inducible factor (HIF)-1α activity reporter line and pharmaceutical inhibition of HIF-1α in organoid formation assays. 2.5 µM cadmium reduced primary mammosphere formation and branching structure organoid formation rates by 33% and 87%, respectively. Despite no changes in mammosphere formation, 0.25 µM cadmium inhibited branching organoid formation in hydrogels by 73%. RNA-seq revealed cadmium downregulated genes associated with extracellular matrix formation and EMT, while upregulating genes associated with metal response including metallothioneins and zinc transporters. In the RNA-seq data, cadmium downregulated HIF-1α target genes including LOXL2, ZEB1, and VIM. Cadmium significantly inhibited HIF-1α activity in a luciferase assay, and the HIF-1α inhibitor acriflavine ablated mammosphere and organoid formation. These findings show that cadmium, at doses relevant to human exposure, inhibited human mammary stem cell proliferation and differentiation, potentially through disruption of HIF-1α activity.

Mindfulness-based stress reduction teachers, practice characteristics, cancer incidence, and health: a nationwide ecological description.

BACKGROUND: Studies have demonstrated the potential of the Mindfulness-Based Stress Reduction (MBSR) program to improve the condition of individuals with health outcomes such as hypertension, diabetes, and chronic pain; improve psychological well-being; reduce stress levels; and increase survival among cancer patients. To date, only one study has focused on the effect of long-term meditation on stress, showing a positive protective relationship. However, the relationship between meditation and cancer incidence remains unexplored. The objective of this study was to describe the state-level relationship between MBSR instructors and their practices and county-level health outcomes, including cancer incidence, in the United States. METHODS: This ecologic study was performed using geospatial mapping and descriptive epidemiology of statewide MBSR characteristics and overall health, mental health state rankings, and age-adjusted cancer incidence rates. RESULTS: Weak to moderate state-level correlations between meditation characteristics and colorectal and cervical cancer incidence were detected, with states with more meditation (e.g., more MBSR teachers per population) correlated with a decreased cancer incidence. A negative correlation was detected between lung & bronchus cancer and years teaching MBSR only. Moderate positive correlations were detected between Hodgkin's Lymphoma and female breast cancer in relation to all meditation characteristics. Statistically significant correlations with moderate coefficients were detected for overall health ranks and all meditation characteristics, most strongly for total number of years teaching MBSR and total number of years of general meditation practice. CONCLUSIONS: Our analyses might suggest that a relationship exists between the total number of MBSR teachers per state and the total number of years of general meditation practice per state, and colorectal and cervical cancer incidence. Positive correlations were observed with overall health rankings. Despite this study's limitations, its findings could serve to generate hypotheses and to inform and motivate a new focus on meditation and stress reduction in relation to cancer incidence, with specific relevance to colorectal and cervical cancer.