Preliminary investigation of soil organic carbon distribution and turnover patterns, and potential pollution sources in and around a typical coking plant in North China.

The variation characteristics of soil organic carbon (SOC) in and around the coking plant area are still unclear. In this work, the concentration and stable carbon isotope composition of SOC in coke plant soils were investigated to preliminarily identify the sources of SOC in and around the plant area, and to characterize soil carbon turnover. Meanwhile, the carbon isotopic technique was used to initially identify the soil pollution processes and sources in and around the coking plant area. The results demonstrate that the SOC content (12.76 mg g-1) of the surface soil in the coking plant is about 6 times higher than that outside the coking plant (2.05 mg g-1), and the variation range of δ13C value of the surface soil in the plant (-24.63～-18.55‰) is larger than that of the soil outside the plant (-24.92～-20.22‰). The SOC concentration decreases gradually from the center of the plant outward with increasing distance, and the δ13C in the middle and north of the plant tends to be positive compared with the δ13C in the west and southeast of the plant. As the increase of soil depth, the SOC content and δ13C value in the plant increases. On the contrary, δ13C value and SOC content outside the plant decreases, with a minor variation. Based on the carbon isotope method, the SOC in and around the coking plant area is mainly from industrial activities (e.g., coal burning and coking), and partly from C3 plants. Notably, organic waste gases containing heavy hydrocarbons, light oils, and organic compounds accumulated in the northern and northeastern areas outside the plant due to south and southwest winds, which may pose an environmental health risk.

Health Risk Assessment of Inhalation Exposure to Airborne Particle-Bound Nitrated Polycyclic Aromatic Hydrocarbons in Urban and Suburban Areas of South China.

Airborne particulates (PM2.5 and TSP) were collected from outdoor and indoor areas at urban (Haizhu District) and suburban (Huadu District) sites from 2019 to 2020 in Guangzhou. Three nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) in the airborne particulates were identified by a gas chromatograph equipped with a triple-quadrupole mass spectrometer. In the Haizhu District and Huadu District, the nitro-PAH concentrations in PM2.5 and TSP did not show a significant decrease from winter to summer. From 2019 to 2020, the difference in the average concentration of nitro-PAHs in PM2.5 and TSP in Guangzhou was relatively low and had no statistical significance. The diagnostic ratios of 2-nitrofluorene (2-NF)/1-nitropyrene (1-NP) in TSP are less than five, while for 2-NF/1-NP in outdoor PM2.5 in the summer of 2019 and 2020 are more than five, which indicates that nitro-PAHs in the atmospheric PM2.5 in Guangzhou during summer mainly originated from the secondary formation of atmospheric photochemical reactions between parent PAHs and oxidants (·OH, NO3, and O3). 9-Nitroanthracene (9-NT) made the most significant contribution to the total nitro-PAH concentration. The incremental lifetime cancer risks (ILCRs) of nitro-PAHs in PM2.5 and TSP by inhalation exposure indicated low potential health risks in the urban-suburban of Guangzhou.

Source tracing of potentially toxic elements in soils around a typical coking plant in an industrial area in northern China.

Coking plants are a substantial source of potentially toxic elements (PTEs) in soil. In this study, we examined the concentration of PTEs, the soil physicochemical properties, and the Pb isotopes in the soil inside and around a coking plant in an industrial city in northern China. We analyzed the spatial distribution of PTEs and the pollution risk areas by Igeo index, the enrichment factor (EF), and the Nemerow index, and we quantitatively identified the contribution of PTE pollution sources in the soil on a small- and medium-scale (plant and work section). Our results indicated that the Hg concentration inside the plant and the Cd concentration in the agricultural land around the plant were both relatively high. A comprehensive analysis of the soil in the study area was performed using the positive matrix factorization model and Pb isotope (206/207Pb, 208/206Pb) tracing method, based on the MixSIAR model, this analysis indicated that burning coal was the main source of Pb both inside (46.8%) and outside (26.3%) the coking plant. The pollution emission sources with significant influence on the soil outside the coking plant were diesel vehicles (12.5%), gas tanks (12.4%), and coke ovens (11.5%), while the sources inside the plant were quenching sections (11.1%), atmospheric deposition (11.0%), coke oven sections (9.6%), and diesel vehicles (6.1%). The results of PTE pollution risk zoning and Pb isotope tracing indicated that pollution is more serious in the western part of the plant, which is the area where coking and gas production takes place, and the most serious pollution outside the plant is mainly distributed to the southeast. This study provides theoretical and practical data indicating the contribution of industrial enterprises to soil pollution, and will help identify pollution responsibility and the management of pollution sources.

[Impact of sperm DNA fragmentation on the outcome of frozen-thawed blastocyst transfer in in vitro fertilization and embryo transfer].

OBJECTIVE: To study the impact of sperm DNA fragmentation (DF) on the outcome of frozen-thawed blastocyst transfer in in vitro fertilization and embryo transfer (IVF-ET). METHODS: We retrospectively analyzed 308 cases of routine IVF-ET performed at our Center of Reproductive Medicine from January 2016 to January 2018. According to the sperm DNA fragmentation index (DFI), we divided the patients into a normal DFI (DFI ≤ 15%, n = 114), a moderate DFI (15% < DFI ≤ 30%, n = 103), and a high DFI group (DFI > 30 %, n = 91), and compared the development of embryos and clinical outcomes among the three groups. RESULTS: The blastocyst formation rate was remarkably higher in the normal and moderate DFI groups than in the high DFI group (68.9% and 66.2% vs 58.3%, P < 0.05) but the percentage of available blastocysts exhibited no statistically significant difference between the former two and the latter group (88.1% and 84.0% vs 81.2%, P > 0.05). There were statistically significant differences among the normal, moderate and high DFI groups in the percentage of high-quality blastocysts (80.3% vs 68.8% vs 59.7%, P < 0.05). The implantation rate was dramatically lower in the high DFI group than in the normal and moderate DFI groups (30.4% vs 43.1% and 41.0%, P < 0.05), and so was the clinical pregnancy rate (33.6% vs 43.2% and 40.2%, P < 0.05), but the abortion rate markedly higher in the former than in the latter two groups (16.2% vs 10.0% and 9.8%, P < 0.05). CONCLUSIONS: High sperm DFI can not only significantly reduce the rates of blastocyst formation, available blastocysts and high-quality blastocysts, but also decrease the rates of implantation and clinical pregnancy and increase that of abortion after frozen-thawed blastocyst transfer.

[The effects of infrasound on the blood coagulation function of guinea pigs].

OBJECTIVE: To study the change of the blood coagulation function of guinea pigs exposed to 16 Hz/120 dB, 16 Hz/125 dB infrasound and to explore the mechanism of circulation system damage. METHODS: Seventy-two guinea pigs were divided into 3 groups: the control group, the group exposed to 16 Hz/120 dB infrasound for 1.5 h a day and the group exposed to 16 Hz/125 dB infrasound for 1.5 h a day. Each exposure group was divided into 4 sub-groups (8 guinea pigs a sub-group) which were exposed to infrasound for 1, 7, 14 and 21 d, respectively. The coagulation function and serum nitric oxide (NO) were measured for control group and all sub-groups after exposure to infrasound. RESULTS: The prothrombin time (PT), international normalized ratio (INR) and serum NO of group exposed to 16 Hz/125 dB infrasound were (31.16 ± 3.05) s, 2.53 ± 1.21 and (88.304 ± 52.601) µmol/L, respectively, which were significantly higher than those [(21.36 ± 0.10) s, 1.65 ± 0.07 and (30.943 ± 26.864) µmol/L] of control group (P < 0.05). PT and INR of sub-groups exposed to 16 Hz/125 dB infrasound for 14 and 21 d were significantly higher than those of control group. NO of sub-groups exposed to 16 Hz/125 dB infrasound for 1 week and 2 weeks were significantly higher than that of control group (P < 0.05), but NO of sub-group exposed to 16 Hz/125 dB infrasound for 3 weeks decreased slightly. CONCLUSION: The blood coagulation function of guinea pigs exposed to 16 Hz/125 dB infrasound decreased, PT and INR may be used as the indexes to assess of blood coagulation function change induced by the infrasound exposure.

[Expression and significance of ADP-ribosylation factor 1 (ARF1) in colorectal laterally spreading tumor].

BACKGROUND & OBJECTIVE: Laterally spreading tumor (LST) behaves close to malignant tumor. This study was to search for the genes and functional proteins correlated to growth and development of colorectal LST (CLST), and to reveal the molecular mechanisms of CLST growth pattern and malignant transformation. METHODS: cDNA microarray was used to screen differentially expressed genes among CLST cell line and other 2 colorectal cell lines LoVo and SW480. Different mRNA and protein expressions of the genes were confirmed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. RESULTS: Compared with LoVo and SW480 cells, 58 genes were up-regulated and 39 genes were down-regulated in CLST cells. mRNA level of ADP-ribosylation factor 1 (ARF1) was significantly higher in CLST cells than in SW480 and LoVo cells (0.93 vs. 0.74 and 0.47, P = 0.04); protein level of ARF1 was significantly higher in CLST cells than in LoVo cells. CONCLUSIONS: CLST has specific gene expression profile. ARF1 is overexpressed in CLST, and may mediate specific biological function of CLST.

[Screening of differentially expressed genes related to laterally spreading tumor by cDNA microarray].

OBJECTIVE: To screen differentially expressed genes between laterally spreading tumor (LST) cell line and common colon carcinoma cell lines, and identify new targets and strategies for exploring the pathogenesis of colorectal tumor. METHODS: The total RNA was extracted from the LST, SW480 and LoVo cells, from which purified mRNAs were obtained. The PCR products of 18 816 genes were blotted onto a fibrous membrane to generate the microarray. The mRNAs from the 3 cell lines were reversely transcribed into cDNA probes and labeled with (33)P before hybridization with the cDNA microarray. After thorough washing, the cDNA microarray was scanned and the 3 samples compared. RESULTS AND CONCLUSIONS: A series of differentially expressed genes were found between the 3 samples, and 58 up-regulated and 39 down-regulated genes were identified among the 97 differentially expressed genes, which suggest different pathogeneses of the laterally spreading tumor. Further analysis of the obtained genes can be helpful in understanding the molecular mechanism of colorectal tumors.