RESUMEN
Background Organic ultraviolet (UV) filters are widely used in personal care products. So far, relevant studies on organic UV filters in indoor dust have been reported. Objective This study aims to establish a thermal desorption combined with gas chromatography-mass spectrometry (TD-GCMS) method to identify organic UV filters in indoor air collected from different indoor environments, so as to reveal the pollution levels and characteristics of organic UV filters in indoor environment. Methods Based on the standard indoor air sampling protocol, a total of 60 samples were collected from eight different kinds of indoor environments (male and female dormitory rooms, offices, labs, barber shops, printing shops, hotels, and private cars) on and nearby Minhang Campus of Shanghai Jiao Tong University from August to November, 2020. The concentrations of six common organic UV filters, including homosalate (HMS), 2-ethylhexyl salicylate (EHS), 3-(4-methylbenzylidene)-camphor (4-MBC), isoamyl 4-methoxycinnamate (IMC), octocrylene (OC), and octyl 4-methoxycinnamate (EHMC), in the air of different indoor environments were detected by TD-GCMS. Furthermore, the correlations of individual organic UV filters in different indoor environments were analysed. Results Under optimized detection conditions, the correlation coefficients of the quantitative standard curves of selected six organic UV filters were all at or above 0.997. The relative standard deviations of 1 mg·L−3 samples ranged from 1.74% to 7.11%, and the recoveries ranged from 67.17% to 106.5%. The relative standard deviations of 10 mg·L−3 samples ranged from 3.59% to 8.76%, and the recoveries ranged from 78.80% to 126.60%. The detection rates of the other five organic UV filters except IMC were all at or more than 92% in eight different kinds of indoor air. The median concentration of total organic UV filters was 75.17 ng·m−3, and EHS presented the highest median concentration of 28.55 ng·m−3. Regarding different indoor environments, the highest concentration of total organic UV filters was found in the female dormitory samples, 154.98 ng·m−3. The respective pair-analysis among HMS, EHMC, OC, and EHS of all indoor air samples reached a significant level of correlation (r=0.40-0.61, P<0.01). Conclusion The TD-GCMS method is satisfactory for the determination of organic UV filters in indoor air. EHS, EHMC, HMS, OC, and 4-MBC are identified in selected eight indoor environments, and they may have similar sources of pollution.
RESUMEN
Objective To evaluate the therapeutic effects of recombinant expression plasmid containing hepatocyte growth factor (HGF) and augmenter of liver regeneration (ALR) on rats with hepatic fibrosis. Methods Ninety Sprague-Dawley rats, which had been established into hepatic fibrosis models, were equally divided into 6 groups: blank group, pcDNA3.1 therapy group,pcDNA3.1-HGF therapy group, pcDNA3. 1-ALR therapy group, pcDNA3.1-HGF and pcDNA3. 1-ALR combined therapy group, and pcDNA3. 1-HGF-ALR therapy group. Zero point one μmol of blank or plasmid was injected into model rats in each group by tail vein once a day for 3 days. Model rats in blank group didn't receive any treatment. Additional 10 rats were chosen as control group, which were not given any interference during the experiment. All rats were sacrificed 4 days after end of treatment. Liver tissues were reserved for observing pathologic changes after HE staining and detecting proliferating cell nuclear antigen (PCNA) and c-jun by immunohistochemistry. Measurement data were compared by single-factor analysis of variance. Comparison between groups was done by SNK test. Enumeration data were analyzed by Fisher's exact test. Results In blank group and pcDNA3.1 therapy group, hyperplasia of fibrous connective tissue was very obvious, false lobules were formed. There was no significant difference between these two groups (x2 =0. 317,P= 1. 000).In the 4 remaining groups, hepatic fibrosis all achieved different degree of amelioration, and the therapeutic effect of pcDNA3.1-HGF-ALR was optimal. In control group, the expressions of PCNA and c-jun in liver tissues were low, with absorbance value of 8.6±1.9 and 3.2 ± 1.2, respectively. In blank group and pcDNA3. 1 therapy group, the expressions of PCNA and c-jun were obviously increased, with absorbance value of 24. 1±3.0, 24.5±4.3 and 23.8±3.1, 24.9±4.2, respectively,which were significant different from control group (all P＜0.01). In the 4 remaining groups, the expressions of PCNA were all obviously increased, and expressions of c-jun were all obviously decreased. The maximum change scope was observed in pcDNA3. 1-HGF-ALR therapy group.Conclusions The recombinant expression plasmid pcDNA3. 1-HGF-ALR can effectively ameliorate experimental hepatic fibrosis of rats. The anti-fibrosis effects are achieved probably by up-regulating PCNA expression and down-regulating c-jun expression.