Ozone exposure and schoolchildren

The average annual ozone levels have been increasing in Japan, even though the high ozone levels have decreased in recent years. There is limited information on the relationship between ozone exposure, pulmonary function, and respiratory symptoms in schoolchildren in Japan. The aim of this study was to investigate the effects of short-term ozone exposure on pulmonary function and respiratory symptoms in Japanese schoolchildren. Afternoon peak expiratory flow (PEF) values and respiratory symptom scores were recorded daily in 276 schoolchildren from September to October 2016 and from January to February 2017. The association of daily ozone levels with PEF was assessed using a linear mixed model and that with respiratory symptoms was evaluated by generalized estimating equations logistic regression analysis. There was a significant association of daily ozone levels with PEF values. A 13.6-ppb increment in the interquartile range for ozone exposure was significantly associated with a decrease in PEF of −3.67 L/min (95% confidence interval −4.73, −2.61). However, increased ozone levels were not associated with an increased risk of respiratory symptoms. Our present findings suggest that more attention should be paid to the potential adverse effects of short-term ozone exposure on pulmonary function in schoolchildren

Effect of Asian dust on pulmonary function in adult asthma patients in western Japan: A panel study

AbstractBackgroundAsian dust (AD) has become a major health concern. The concentration of AD is typically expressed in particulate matter less than 10 μm (PM10) and 2.5 μm (PM2.5). However, PM10 and PM2.5 consist of various substances besides AD. Light detection and ranging (LIDAR) systems can selectively measure the quantity of AD particles to distinguish non-spherical airborne particles from spherical airborne particles. The objective of this study was to investigate the relationship between pulmonary function in adult asthma patients and AD using LIDAR data.MethodsSubjects were 231 adult asthma patients who had their morning peak expiratory flow (PEF) measured from March to May 2012. A linear mixed model was used to estimate the association of PEF with sand dust particles detected by LIDAR.ResultsIncreases in the interquartile range of AD particles (0.018 km−1) led to changes in PEF of −0.42 L/min (95% confidence interval [CI], −0.85 to 0.01). An increase of 11.8 μg/m3 in suspended particulate matter and 6.9 μg/m3 in PM2.5 led to decreases of −0.17 L/min (−0.53 to 0.21) and 0.03 L/min (−0.35 to 0.42), respectively. A heavy AD day was defined as a day with a level of AD particles >0.032 km−1, which was the average plus one standard deviation during the study period, and six heavy AD days were identified. Change in PEF after a heavy AD day was −0.97 L/min (−1.90 to −0.04).ConclusionsHeavy exposure to AD particles was significantly associated with decreased pulmonary function in adult asthma patients

Difference in interleukin-8 transcriptional activity induced in THP-G8 cells by particulate matter collected in winter and summer in western Japan

Background : Airborne particulate matter (PM) may stimulate production of pro-inflammatory cytokines, and thus exposure to PM affects pulmonary diseases. However, the effects of PM on pulmonary diseases have differed among studies. Methods : PM was collected from February 2 to 28 (winter) and June 1 to 17 (summer) in 2013 in Yurihama, Japan, using filters to separate particles with different aerodynamic diameters (1.1 to< 2.2 μm, 2.2 to< 3.3 μm, 3.3 to< 7.0 μm, and 7.0 to< 10 μm). Interleukin (IL)-8 transcriptional activity in THP-G8 cells was examined in response to winter and summer PM with different diameters. Results : IL-8 transcriptional activity induced by winter PM was significantly higher than that with summer PM for each diameter. For winter PM, IL-8 activity increased with an increased diameter, whereas this activity did not differ between a solvent control and each summer PM diameter. This indicates that summer PM does not stimulate production of IL-8 in THP-G8 cells. Conclusion : The effects of PM on production of pro-inflammatory cytokines differ with the season and PM diameter. This suggests that the compositions of PM differ on season, and the evaluation of compositions of PM is important in understanding the association of health with short-term exposure to PM

The Constrained Maximal Expression Level Owing to Haploidy Shapes Gene Content on the Mammalian X Chromosome.

X chromosomes are unusual in many regards, not least of which is their nonrandom gene content. The causes of this bias are commonly discussed in the context of sexual antagonism and the avoidance of activity in the male germline. Here, we examine the notion that, at least in some taxa, functionally biased gene content may more profoundly be shaped by limits imposed on gene expression owing to haploid expression of the X chromosome. Notably, if the X, as in primates, is transcribed at rates comparable to the ancestral rate (per promoter) prior to the X chromosome formation, then the X is not a tolerable environment for genes with very high maximal net levels of expression, owing to transcriptional traffic jams. We test this hypothesis using The Encyclopedia of DNA Elements (ENCODE) and data from the Functional Annotation of the Mammalian Genome (FANTOM5) project. As predicted, the maximal expression of human X-linked genes is much lower than that of genes on autosomes: on average, maximal expression is three times lower on the X chromosome than on autosomes. Similarly, autosome-to-X retroposition events are associated with lower maximal expression of retrogenes on the X than seen for X-to-autosome retrogenes on autosomes. Also as expected, X-linked genes have a lesser degree of increase in gene expression than autosomal ones (compared to the human/Chimpanzee common ancestor) if highly expressed, but not if lowly expressed. The traffic jam model also explains the known lower breadth of expression for genes on the X (and the Z of birds), as genes with broad expression are, on average, those with high maximal expression. As then further predicted, highly expressed tissue-specific genes are also rare on the X and broadly expressed genes on the X tend to be lowly expressed, both indicating that the trend is shaped by the maximal expression level not the breadth of expression per se. Importantly, a limit to the maximal expression level explains biased tissue of expression profiles of X-linked genes. Tissues whose tissue-specific genes are very highly expressed (e.g., secretory tissues, tissues abundant in structural proteins) are also tissues in which gene expression is relatively rare on the X chromosome. These trends cannot be fully accounted for in terms of alternative models of biased expression. In conclusion, the notion that it is hard for genes on the Therian X to be highly expressed, owing to transcriptional traffic jams, provides a simple yet robustly supported rationale of many peculiar features of X's gene content, gene expression, and evolution

The effects of TYB-2285 and its metabolites on eosinophil adhesion to tumor necrosis factor α-stimulated human umbilical vein endothelial cells

The effects of TYB-2285 and its metabolites (TC-286 and TC- 326) on the adhesion of eosinophils and neutrophils to cultured human umbilical vein endothelial cells (HUVEC) stimulated with tumour necrosis factor α (TNF-α) were investigated. The treatment of HUVEC with TNF-α enhanced eosinophil adhesion in a dose-dependent manner (1–100 U/mL). The adhesion of eosinophils to TNF-α (100U/mL)-stimulated HUVEC was inhibited by TYB-2285 and its metabolites in a dose-dependent manner (10−8–10−5mol/L). These compounds showed stronger inhibitory effects than any other anti-allergic drugs, such as disodium cromoglycat (DSCG), ketotifen and tranilast. TYB-2285, TC-286 and TC-326 did not inhibit the adhesion of neutrophils at the same range (10−8–l 0−5 mol/L). In our adhesion assay system, eosinophil adhesion to TNF-α-stimulated HUVEC was blocked by monoclonal antibody against VLA-4 (anti-VLA-4) but not by that against Mac-1 (anti-Mac-1). In contrast, neutrophil adhesion was blocked by anti-Mac-1, but not by anti-VLA-4. The results of the present study demonstrate that TYB-2285 and its metabolites selectively inhibit the adhesion of eosinophils to HUVECs stimulated with TNF-α and also suggest that TYB-2285, TC-286 and TC-326 might block the VLA-4/VCAM-1 pathway selectively