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Background: Numerous epidemiological studies have recently observed that exposure to traffic-related air pollution (TRAP) is associated with increased risk of various respiratory diseases. Major gaps in knowledge remain regarding the toxicological effects., Objectives: We examined the toxicological effects of the gasoline exhaust particles (GEP), a paradigm of TRAP, in rats, with an objective to provide the evidence, obtain the biomarkers, and suggest effective intervention measure., Methods: We measured the airway hyperresponsiveness (AHR), inflammatory cells in the bronchoalveolar lavage (BAL) fluid, histological changes in the lung tissues, and the biomarkers so as to systematically examine the toxicological effects of GEPs at different dose levels (0.5, 2.5, 5 mg/kg BW). The intervention of vitamin E (VE), a natural antioxidant, on the toxicological effects was investigated., Results: The lung injury caused by GEP exposure was first indicated by the airway hyperresponsiveness (AHR). Compared with the control group, GEP exposure significantly increased the airway resistances and decreased the lung compliance; the higher the dose of GEP, the more serious the lung injury. Lung injury was also revealed by the increase of inflammatory cells, including the lymphocytes and neutrophils, in the BAL fluid. With the increase of GEP dose, histological changes in the lung tissues were further observed: inflammatory cell infiltration increased and alveolar wall thickened. The toxicology of GEP was demonstrated by the increase of the biomarkers of the oxidative stress, the pro-inflammatory cytokines and the apoptosis cytokine. However, administration of VE was found to be effective in restoring airway injury., Conclusion: The toxicological effects of traffic-related air pollution (TRAP) on rat lungs are supported by evidence and biomarkers, and vitamin E intervention is feasible., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Although health benefits of physical activity are well known, the risk of physical activity in polluted air is unclear. Our objective is to investigate health effects resulting from physical activity in polluted air by looking at particle deposition in human tracheobronchial (TB) airways. Airflow and particle deposition in TB airways were investigated using a computational fluid dynamics (CFD) method. We chose three regional airways: upper (G3-G5), central (G9-G11) and lower (G14-G16). Physical activity was described by breathing rate at the mouth, for three levels of activity: sedentary (15 l/min), moderate (30 l/min) and intense (60 l/min). We found that particle deposition was strongly affected by physical activity. Particles are deposited in greater number in the lower airways (G14-G16) during sedentary activity, more in the upper airways (G3-G5) during intense activity, and uniformly in the airways during moderate activity. The difference in the deposition pattern was due to the reason that physical activity increased the airflow which increased inertial impaction. Our modeling of particle deposition in the human respiratory airways shows that there are different health effects for different activity levels: sedentary activity leads to chronic health effects, intense activity results in acute effects, and moderate activity minimizes the adverse health effects of physical activity in polluted air., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Although ambient particulate matter or particles have been found to be associated with morbidity and mortality all over the world, specific health effects of particles from different sources need further elucidation. The objective of this work is to predict the deposition of particles from different sources in the human lung. The whole lung, consisting of 24 generations of branches from trachea to alveoli, was approximated using a one-dimensional lumped "trumpet" model with a variable cross-sectional area. The aerosol dynamics equation was numerically solved using a finite difference method to investigate the transport and deposition of particles in the lung model. Particles from various sources were assumed to be different in both size and density. We found that in general, coarse particles (> 2.5 µm) were mainly deposited in the tracheobronchial (TB) region by impaction, and fine particles (< 2.5 µm) were mainly deposited in the pulmonary (P) region by sedimentation and diffusion. However, the coarse particles with low density can be deposited in P region by sedimentation. As a comparison, our results found that soil particles, which are coarse with low density, were deposited in the deep lung more than traffic particles, which are fine with high density. Modeling of particle deposition in the human lung indicated that coarse particles generated by crustal sources may have adverse health effects as strong as those resulting from fine particles generated from combustion sources., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Common cold is a frequent upper respiratory tract infection, but the role of ambient temperature in the infection is unclear., Objective: We investigated the role of prenatal exposure to diurnal temperature variation (DTV), the difference between the daily maximal and minimal temperatures, in the risk of common cold in children., Methods: We conducted a cohort study of 2598 preschool children in Changsha, China. Occurrence of common cold during the past year was surveyed using questionnaire. We then estimated each child's prenatal exposure to DTV during pregnancy. Multivariate logistic regression model was used to examine the association between occurrence of common cold and prenatal exposure to DTV in terms of odds ratios (OR) and 95% confidence interval (CI)., Results: About 45% children have common cold (≥3 times) during the past year. We found that common cold in children was associated with maternal DTV exposure during pregnancy, particularly during the first trimester with adjusted OR (95% CI) = 1.27 (1.10-1.46). Male and atopic children were more susceptible to the effect of DTV during pregnancy. The risk of common cold due to DTV is higher in children living in the suburban areas and the bigger houses and in those exposed to environmental tobacco smoke, mold/dampness, new furniture and redecoration. We observed that the risk of common cold in children has been increased in recent years due to increasing DTV., Conclusions: Common cold in children was associated with maternal exposure to temperature variation during pregnancy, suggesting that the risk of common cold may originate in pregnancy., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Thermal comfort in traditionally uniform environment is apparent and can be improved by increasing energy expenses. To save energy, non-uniform environment implemented by personalized conditioning system attracts considerable attention, but human response in such environment is unclear., Objectives: To investigate regional- and whole-body thermal sensation and comfort in a cool environment with personalized heating., Methods: In total 36 subjects (17 males and 19 females) including children, adults and the elderly, were involved in our experiment. Each subject was first asked to sit on a seat in an 18°C chamber (uniform environment) for 40min and then sit on a heating seat in a 16°C chamber (non-uniform environment) for another 40min after 10min break. Subjects' regional- and whole-body thermal sensation and comfort were surveyed by questionnaire and their skin temperatures were measured by wireless sensors. We statistically analyzed subjects' thermal sensation and comfort and their skin temperatures in different age and gender groups and compared them between the uniform and non-uniform environments., Results: Overall thermal sensation and comfort votes were respectively neutral and just comfortable in 16°C chamber with personalized heating, which were significantly higher than those in 18°C chamber without heating (p<0.01). The effect of personalized heating on improving thermal sensation and comfort was consistent in subjects of different age and gender. However, adults and the females were more sensitive to the effect of personalized heating and felt cooler and less comfort than children/elderly and the males respectively. Variations of the regional thermal sensation/comfort across human body were consistent with those of skin temperature., Conclusions: Personalized heating significantly improved human thermal sensation and comfort in non-uniform cooler environment, probably due to the fact that it increased skin temperature. However, the link between thermal sensation/comfort and variations of skin temperature is rather complex and warrant further investigation., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Numerous enzymes have been found to catalyze additional and completely different types of reactions relative to the natural activity they evolved for. This phenomenon, called catalytic promiscuity, has proven to be a fruitful guide for the development of novel biocatalysts for organic synthesis purposes. As such, enzymes have been identified with promiscuous catalytic activity for, one or more, eminent types of carbon-carbon bond-forming reactions like aldol couplings, Michael(-type) additions, Mannich reactions, Henry reactions, and Knoevenagel condensations. This review focuses on enzymes that promiscuously catalyze these reaction types and exhibit high enantioselectivities (in case chiral products are obtained)., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: Deleted in lung and esophageal cancer 1 (DLEC1) gene was a new candidate tumor suppressor gene. We determined the expression level and methylation status of DLEC1 in non-small-cell lung cancer (NSCLC), and the DLEC1 methylation in plasma DNA as a biomarker for NSCLC was further evaluated., Patients and Methods: The study population enrolled 78 paired NSCLC specimens and adjacent normal tissues and 25 benign pulmonary lesions. Meanwhile, corresponding plasma samples were collected. Methylation-specific polymerase chain reaction (PCR) was used to detect the DLEC1 methylation status. DLEC1 gene expression was determined by reverse transcriptase PCR and immunohistochemistry., Results: Hypermethylation of DLEC1 was found in 41% (32/78) of NSCLC tissues, which was significantly higher than that of adjacent normal tissues (3.8%; 3/78) and benign lesions (0/25; P < .001). Also, DLEC1 methylation was closely correlated with loss of expression, and treatment with 5-aza-2'-deoxycytidine induced DLEC1 restoration in A549 and SPC-A1 cell lines. Furthermore, DLEC1 hypermethylation was associated with advanced stage (P = .011) and lymph node metastasis (P = .019). Methylated DLEC1 was detected in 35.9% (28/78) of plasma samples from NSCLC patients and only 2% (1/50) in cancer-free controls, and the concordance of DLEC1 methylation status in plasmas and corresponding tumor tissues was good., Conclusion: DLEC1 is silenced by promoter methylation in NSCLC specimens and is widely expressed in adjacent normal tissues and benign control samples. The high detection rate of methylated DLEC1 in plasma DNA further indicates its potential diagnostic and prognosis values in NSCLC.