Imaging methods used in the assessment of environmental disease networks: a brief review for clinicians

Brain gray matter volume of reward-related structures in Inuit adolescents pre- and postnatally exposed to lead, mercury and polychlorinated biphenyls

This study aimed to assess associations between prenatal and postnatal exposure to lead (Pb), mercury (Hg) and polychlorinated biphenyls (PCBs) and gray matter volume of key regions of the brain reward circuit, namely the caudate nucleus, putamen, nucleus accumbens (nAcc), the amygdala, the orbitofrontal cortex (OFC) and the anterior cingulate cortex (ACC). Structural magnetic resonance imaging (MRI) was conducted in 77 Inuit adolescents (mean age = 18.39) from Nunavik, Canada, who also completed the Brief Sensation Seeking Scale (BSSS-4) and Sensation Seeking - 2 (SS-2), two self-report questionnaires evaluating the tendency toward sensation seeking, which is a proxy of reward-related behaviors. Exposures to Pb, Hg and PCBs were measured in cord blood at birth, in blood samples at 11 years old and at time of testing (18 years old). Multivariate linear regressions were corrected for multiple comparisons and adjusted for potential confounders, such as participants' sociodemographic characteristics and nutrient fish intake. Results showed that higher cord blood Pb levels predicted smaller gray matter volume in the bilateral nAcc, caudate nucleus, amygdala and OFC as well as in left ACC. A moderating effect of sex was identified, indicating that the Pb-related reduction in volume in the nAcc and caudate nucleus was more pronounced in female. Higher blood Hg levels at age 11 predicted smaller right amygdala independently of sex. No significant associations were found between blood PCBs levels at all three times of exposure. This study provides scientific support for the detrimental effects of prenatal Pb and childhood Hg blood concentrations on gray matter volume in key reward-related brain structures.

Quantitative Imaging Metrics for the Assessment of Pulmonary Pathophysiology: An Official American Thoracic Society and Fleischner Society Joint Workshop Report

Multiple thoracic imaging modalities have been developed to link structure to function in the diagnosis and monitoring of lung disease. Volumetric computed tomography (CT) renders three-dimensional maps of lung structures and may be combined with positron emission tomography (PET) to obtain dynamic physiological data. Magnetic resonance imaging (MRI) using ultrashort-echo time (UTE) sequences has improved signal detection from lung parenchyma; contrast agents are used to deduce airway function, ventilation-perfusion-diffusion, and mechanics. Proton MRI can measure regional ventilation-perfusion ratio. Quantitative imaging (QI)-derived endpoints have been developed to identify structure-function phenotypes, including air-blood-tissue volume partition, bronchovascular remodeling, emphysema, fibrosis, and textural patterns indicating architectural alteration. Coregistered landmarks on paired images obtained at different lung volumes are used to infer airway caliber, air trapping, gas and blood transport, compliance, and deformation. This document summarizes fundamental "good practice" stereological principles in QI study design and analysis; evaluates technical capabilities and limitations of common imaging modalities; and assesses major QI endpoints regarding underlying assumptions and limitations, ability to detect and stratify heterogeneous, overlapping pathophysiology, and monitor disease progression and therapeutic response, correlated with and complementary to, functional indices. The goal is to promote unbiased quantification and interpretation of in vivo imaging data, compare metrics obtained using different QI modalities to ensure accurate and reproducible metric derivation, and avoid misrepresentation of inferred physiological processes. The role of imaging-based computational modeling in advancing these goals is emphasized. Fundamental principles outlined herein are critical for all forms of QI irrespective of acquisition modality or disease entity.

Association between environmental composite quality index score and obesity in children and their family: A cross-sectional study in northeast China

BACKGROUND

Childhood obesity has emerged as a severe public health problem worldwide. Most studies focused on the association between single environmental risk factors and obesity. Thus, we investigate the association between environmental composite quality index (ECQI) score and obesity in children and their families.

METHOD

The cross-sectional study was conducted among 2354 children and 1761 mothers in Fuxin City, Liaoning Province, in 2015. The information was collected by questionnaires, including environmental factors, heights, weights, and sociodemographic data. We quantitated thirteen indoor and outdoor risk factors and constructed the ECQI. There were 4 household environmental factors in the household air quality index (HAQI) and 9 variables to evaluate the outdoor environmental quality index (OEQI). Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using the binary logistic regression model after adjusting the most common obesity risk factors.

RESULTS

A higher ECQI score was correlated with a higher risk of childhood obesity and family obesity. Comparing the ECQI score 0-2 to the ECQI score ≥5, ORs with childhood obesity was 1.73 (95%CI, 1.25-2.39, P for trend = 0.001), and 1.53 for family obesity (95%CI, 1.09-2.15; P for trend = 0.003) after adjusted confounding factors. Similarly, a significantly positive association was found between OEQI score, HAQI score, and childhood obesity, family obesity.

CONCLUSION

A higher ECQI score was associated with an increased risk of obesity in children and their families. Both HAQI score and OEQI score were associated to childhood obesity and family obesity. Further studies should elucidate the underlying mechanisms.

COVID-19 related mortality in older adults: analysis of the first wave in Colombia and Mexico

OBJECTIVE

The aim of this study is to describe the mortality among older adults in the first wave of COVID-19 in Colombia and Mexico.

METHODS

This is an observational, prospective study on data obtained from open data sets that are publicly available on the websites of the health ministries of the respective countries. COVID-19 cases, age, sex, date to mortality, and mortality itself were analyzed with Kaplan-Meier curves and Cox regressions.

RESULTS

Data on 1 779 877 individuals were analyzed, 58.2% from Mexico, with a higher frequency of men for both countries, and 11.7% were older adults. Survival curves show a continuous increase in mortality for Mexico, with higher rates for older adults, while for Colombia the mortality was observed up to 50 days of the follow-up. Finally, hazard ratios were higher for older adults in both countries. Colombia implemented a rigid curfew for older adults, and the effect on mortality is clear from the survival curves.

CONCLUSIONS

This finding shows the potential benefit that public policies could have on older adults.