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Interleukin (IL)-18, a proinflammatory cytokine, has been recognized recently as an important factor in both treated and untreated patients with human immunodeficiency virus type 1 (HIV-1) infection. Consistent with all earlier reports, our quantification of serum IL-18 concentrations in 88 HIV-1 seropositive, North American adolescents (14–18 years old) revealed a positive correlation with cell-free HIV-1 viral load at two separate visits (Spearman's r = 0·31 and 0·50, respectively, P < 0·01 for both), along with a negative correlation with CD4+ T cell counts ( r = –0·31 and −0·35, P < 0·01 for both). In additional analyses of 66 adults (21–58 years old) from Zambia, HIV-1 seroconversion was associated uniformly with elevated IL-18 production ( P < 0·0001). These epidemiological relationships were independent of other population-related characteristics, including age, gender and ethnicity. In neither study population could serum IL-18 concentrations be associated with the IL-18 gene ( IL18) promoter genotypes defined by five major single nucleotide polymorphisms. Collectively, these findings suggest that circulating IL-18 rather than the IL18 genotype may provide a useful biomarker for HIV-1-related events or outcomes. [ABSTRACT FROM AUTHOR]

Herbicide 2,4-Dichlorophenoxyacetic acid (2,4-D) and its analogues are widely used in agriculture. Although the occurrence of 2,4-D in urine has been widely reported in North America, it has scarcely been investigated in China, especially in young children. In addition, both invivo and in vitro studies have shown that high-level 2,4-D exposure is associated with oxidative stress, but their association in a general sensitive population has rarely been evaluated. In this study, 2,4-D and its analogues were measured in 417 urine samples collected from 139 children aged 0-7 during the non-peak season of pesticide application in Wuhan, central China, and Shenzhen, south China. Each of them provided three samples in three consecutive days. An oxidative stress biomarker, 8-hydroxy-2-deoxyguanosine (8-OHdG), was also measured. The geometric mean (GM) of unconjugated urinary 2,4-D concentration was 0.10 μg/L (corrected by urinary specific gravity, SG-corrected). After β-glucuronidase hydrolysis, the GM of SG-corrected urinary 2,4-D was 0.15 μg/L, and the detection frequency was 100%. Moderate inter-day reproducibility was found within individuals, with an intraclass correlation coefficient of 0.68 for SG-corrected urinary deconjugated 2,4-D. The GM of estimated daily intake of 2,4-D was 6.05 ng/kg-bw/day. A significant positive correlation was found between urinary 2,4-D and 8-OHdG, whereas no association was found after SG-correction. This is the first study to characterize the occurrence of urinary 2,4-D, its inter-day reliability, and its association with urinary 8-OHdG in young children from China., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Isocyanic acid (HNCO) is a potentially toxic atmospheric pollutant, whose atmospheric concentrations are hypothesized to be linked to adverse health effects. An earlier model study estimated that concentrations of isocyanic acid in China are highest around the world. However, measurements of isocyanic acid in ambient air have not been available in China. Two field campaigns were conducted to measure isocyanic acid in ambient air using a high-resolution time-of-flight chemical ionization mass spectrometer (ToF-CIMS) in two different environments in China. The ranges of mixing ratios of isocyanic acid are from below the detection limit (18 pptv) to 2.8 ppbv (5 min average) with the average value of 0.46 ppbv at an urban site of Guangzhou in the Pearl River Delta (PRD) region in fall and from 0.02 to 2.2 ppbv with the average value of 0.37 ppbv at a rural site in the North China Plain (NCP) during wintertime, respectively. These concentrations are significantly higher than previous measurements in North America. The diurnal variations of isocyanic acid are very similar to secondary pollutants (e.g., ozone, formic acid, and nitric acid) in PRD, indicating that isocyanic acid is mainly produced by secondary formation. Both primary emissions and secondary formation account for isocyanic acid in the NCP. The lifetime of isocyanic acid in a lower atmosphere was estimated to be less than 1 day due to the high apparent loss rate caused by deposition at night in PRD. Based on the steady state analysis of isocyanic acid during the daytime, we show that amides are unlikely enough to explain the formation of isocyanic acid in Guangzhou, calling for additional precursors for isocyanic acid. Our measurements of isocyanic acid in two environments of China provide important constraints on the concentrations, sources, and sinks of this pollutant in the atmosphere.