[Pollution Characteristics and Risk Assessment of Antibiotics in Beiyun River Basin in Beijing].

To investigate the pollution characteristics and risk levels of antibiotics in water of the Beiyun River Basin in Beijing, the concentration of antibiotics was analyzed by using the solid-phase extraction and high-performance liquid chromatography-tandem mass spectrometry (SPE-HPLC-MS/MS) method. The results showed that seven types of four categories of antibiotics were detected in the samples from 12 sampling points; the total concentration of antibiotics including sulfapyridine, clarithromycin, azithromycin, roxithromycin, erythromycin, ofloxacin, and lincomycin ranged from 59.19 to 703.44 ng·L-1. Among these antibiotics, the detection rate of clarithromycin, azithromycin, roxithromycin, ofloxacin, and lincomycin was 100%; that of erythromycin was 41.67%; and that of sulfapyridine was 33.33%. Compared with that in some rivers in China, the Azithromycin, Erythromycin, and Clarithromycin in the Beiyun River Basin were at a relatively high level. The ecological risk assessment results showed that the most sensitive species was algae. The health risk quotients indicated that sulfapyridine, lincomycin, roxithromycin, azithromycin, and erythromycin presented no risk for every age group, whereas the health risk of clarithromycin was at a low level.

[Variation in Pollutant Concentrations and Correlation Analysis with the Vegetation Index in Beijing-Tianjin-Hebei].

Based on 2017 hourly air quality monitoring data, NDVI 16 d synthetic data, and socio-economic data, the air pollution characteristics of Beijing-Tianjin-Hebei were systematically analyzed, and its variation, normalized vegetation index, and the relationship between the index (NDVI) and its impact on socio-economic factors, were analyzed by linear regression analysis and a geographically weighted regression model. The conclusions are as follows:①The overall air pollution in the Beijing-Tianjin-Hebei region is characterized by high-level pollution over the southern plain areas and low-level pollution over the northern mountainous areas. The air pollution increases from north to south, and shows significant spatial heterogeneity. ②From the perspective of seasonal changes, the overall order winter > autumn > spring > summer is observed, and atmospheric pollution in the Beijing-Tianjin-Hebei region shows significant temporal heterogeneity. ③The concentrations of pollutants such as SO2, NO2, CO, PM2.5, and PM10 all have a negative correlation with the NDVI value. Assuming that natural conditions such as climate and topography are relatively consistent, the lower the NDVI value, the more obvious the interference of human activities, the more concentrated the industrial economy layout, and the greater the pollution emissions, the more significant the negative impact on air quality. ④The NDVI reflects the land use, population distribution, and industrial layout to a certain extent, and these factors directly or indirectly determine the level of air pollution emissions and thus indicate the pollution distribution characteristics of the region. ⑤The results of the GWR model calculation show that the higher the level of economic development, the better the correlation between the NDVI and socioeconomic factors, PM2.5, and other pollutant concentrations. The distribution of the NDVI can generally reflect the level of social and economic development. The distribution of the NDVI also correlates to the distribution of PM2.5 to a certain extent.

Complementary feeding patterns among ethnic groups in rural western China.

OBJECTIVE: This study investigated complementary feeding practices among four ethnic groups (Han, Uygur, Tibetan, and Zhuang) based on a cross-sectional survey in rural western China. METHODS: In 2005, a stratified multistage cluster random sampling method was used to recruit 9712 children (7411 Han, 1032 Uygur, 678 Tibetan, and 591 Zhuang) between 6 and 35 months of age and their mothers from 45 counties in 10 provinces (autonomous regions, municipalities) in western China. RESULTS: The rates of early introduction (before 6 months) of complementary foods in four ethnic groups (Han, Uygur, Tibetan, and Zhuang) were 71.30%, 95.95%, 82.40%, and 72.30%, respectively. The Infant and Child Feeding Index (ICFI) for Uygur and Tibetan children was lower than that for Han children at all age groups. Uygur children were more likely to have unqualified ICFI compared with Han children in a multivariate logistic regression (odds ratio (OR)=5.138, 95% confidence interval (CI): 4.340-6.084). A higher level of maternal education, greater family wealth, and the availability of complementary feeding educational materials decreased the likelihood of an unqualified ICFI. The nutritional status of children (Han, Tibetan, and Zhuang) with qualified ICFI was better than that for children with unqualified ICFI. CONCLUSIONS: Appropriate interventions are required to improve complementary feeding practices in rural western China.

Assessment of DNA Damage and Cell Senescence in Corneal Epithelial Cells Exposed to Airborne Particulate Matter (PM2.5) Collected in Guangzhou, China.

PURPOSE: To assess the genotoxic effect of airborne particulate matter on corneal epithelial cells and investigate the role of reactive oxygen species (ROS) formation in this process. METHODS: Immortalized human corneal epithelial cells (HCECs) and primary bovine corneal epithelial cells were exposed to airborne particulate matter collected from Guangzhou for 24 hours. The cell viability and toxicity were measured by the CCK-8 test and lactate dehydrogenase (LDH) release, respectively. The DNA breaks and DNA repair were examined by alkaline comet assay and by immunofluorescence staining of the phosphorylated histone variant H2AX (γH2AX), respectively. Reactive oxygen species production was assessed by the fluorescent probe, CM-H2DCFDA. Cell senescence was evaluated with senescence-associated ß-Galactosidase staining, and cell ultrastructure was observed with transmission electron microscopy. RESULTS: Exposure to PM2.5 at the concentration of 20 µg/mL to 200 µg/mL decreased cell viability and increased LDH release. Remarkably increased DNA double-stand breaks, increased expression of DNA repair-related protein γH2AX, elevated ROS formation, and altered cell ultrastructure were observed in HCECs after treatment with PM2.5. The genotoxic effect of PM2.5 was attenuated by the ROS inhibitor N-acetyl-l-cysteine (NAC). CONCLUSIONS: Particulate matter 2.5 could induce DNA damage and cell senescence in corneal epithelial cells, probably by promoting ROS formation. Thus, whether long-term exposure of PM2.5 might be related to potential risk of abnormality in corneal epithelium renewal and regeneration should be further investigated.

Assessment of flavonoids and volatile compounds in tea infusions of water lily flowers and their antioxidant activities.

Water lily, a member of the Nymphaeaceae family, can be made into tea on the basis of outstanding fragrance characteristics and health care functions. In this study, 16 flavonoids were identified and quantified in tea infusions prepared from the petals of 33 water lily cultivars using HPLC-DAD and HPLC-ESI-MS/MS. The infusions were analyzed with HS-SPME coupled with GC-MS; 29 volatile compounds were detected, of which nine were found to be scent components. The cultivars were clustered into three clusters characterized according to scent components. The 'Conqueror' and 'Virginia' cultivars had the highest antioxidant activities. The concentrations of polyphenols and flavonoids showed significant positive correlations with antioxidant activity as measured by DPPH, ABTS(+), and FRAP assays. This study is valuable for a fuller understanding of this important tea and can also be used for the development of water lily.

Analysis of active compounds and antioxidant activity assessment of six popular Chinese Juhua teas.

Chrysanthemum is an important traditional Chinese medicine and is drunk daily as a herbal tea. Chlorogenic acids and flavonoids are generally considered as the bioactive compounds. In this work, six kinds of Juhua Tea were analyzed and their active compounds and antioxidant activities were compared. In total, 32 phenolic compounds were profiled and identified using HPLC-DAD/ESI-MSn, composed of chlorogenic acids (10), flavones (8), chalcones (8), flavanones (4) and flavonols (2). Chalcones were the main flavonoids in Kunlun Xueju (Coreopsis tinctoria) extract, while flavones and chlorogenic acids were dominant in the five Chrysanthemum teas. Total chlorogenic acids content (TCA) was highest in Tai Ju (Chrysanthemum morifolium cv. 'Tai Ju') (8.59 ± 0.87 mg/g DW), and total flavonoids content (TF) was highest in Kunlun Xueju (87.2 ± 7.0 mg/g DW), which were both lowest in Ganye Ju (Chrysanthemum eticuspe) (TCA 0.86 ± 0.26 mg/g DW, TF 1.43 ± 0.41 mg/g DW). Huangin Ju (Anthemis tinctoria) possessed the most flavones (19.7 ± 0.6 mg/g DW). Antioxidant capacity of each drink, assessed by Folin-Ciocalteu, DPPH, ABTS and FRAP assays, consistently showed that Kunlun Xueju extract possessed stronger antioxidant activity than the other five, suggesting that the flavonoids content accounted for the free radical scavenging. The present work provides a method for the characterization and quality control of Juhua Tea. Moreover, it is a guideline for consuming choice, due to the different biological functions resulting from chalcones, chlorogenic acids, and flavones.

Systematic qualitative and quantitative assessment of fatty acids in the seeds of 60 tree peony (Paeonia section Moutan DC.) cultivars by GC-MS.

Seeds from Paeonia ostii and Paeoniarockii have been recently identified as novel resources of α-linolenic acid (ALA) in China. To assess whether tree peony cultivars can be used as oil resource, fatty acids (FAs) in 60 cultivars were monitored and evaluated in this study. The results indicated that the composition and content of FAs varied dramatically among different cultivars, in which ALA, linoleic acid, oleic acid, palmitic acid, and stearic acid were the dominant. The 60 cultivars were classified into six clusters by hierarchical cluster analysis, and they were quite distinct from each other. Finally, six cultivars with high yield and high quality were screened out, comprising of 'Liuliguanzhu', 'Hongguanyupei', 'LSS-2', 'LSS-1', 'Jingshenhuanfa' and 'LSS-11'. These cultivars were appropriately applied in practical oil production. Overall, tree peony oil with abundant unsaturated fatty acids especially ALA was proved to be a top-grade source for edible oil and nutritional supplements.

[Association between socioeconomic status and physical activities in Chinese children].

OBJECTIVE: To study the daily physical activity patterns of pupils in Beijing, and to identify the association between the socioeconomic status (SES) and physical activities. METHODS: 1502 pupils were recruited from 2 - 5 grades of eight primary schools in Beijing. Information on physical activity, sedentary activity, and transportation styles inside and outside schools were collected using a "7-day physical activity questionnaire". RESULTS: Gymnastics, running, playing games, walking in queues etc. were the most common activities at school, with the proportion as 94.13%, 85.55%, 77.26%, and 71.32% respectively. Physical labor, playing games, running and walking were the common activities outside schools, with the proportion as 72.14%, 69.70%, 65.05%, and 64.64% respectively. However, pupils seldom participated in the ball games. Significant differences between SES groups were observed on the patterns of both physical and sedentary activities. Compared to low-SES pupils, high-SES pupils more frequently participated in dancing, walking upstairs or downstairs, swimming, skating, but less frequently (P < 0.05) in walking, rope skipping, kicking shuttlecock or rubber band skipping. CONCLUSION: Data from our study showed that both the quantity and the distribution of different activities did not meet the need of the Chinese children. Physical activity in association with SES was also demonstrated.