[Variation in Phosphorus Concentration and Flux at Zhutuo Section in the Yangtze River and Source Apportionment].

Phosphorus (P) is a pollutant of great concern in the Yangtze River Basin. The Xiangjiaba Reservoir and Xiluodu Reservoir on the lower reach of the Jinsha River began to operate in 2012 and 2013, respectively, which greatly changed the concentrations of suspended sediment and characteristics of P form and transport in the reservoirs and the downstream reach from Yibin to Jiangjin of the Yangtze River. The Zhutuo section is representative in the water quality of the Yibin-Jiangjin reach, which can not only reflect the comprehensive effects of the formation of the two reservoirs and changes in the aquatic environment in the Min-Tuo Rivers but also reflect the quality of water flowing into the Three Gorges Reservoir. The runoff, concentrations and fluxes of suspended sediments (SS), and P concentrations and fluxes at Zhutuo section were studied during 2002-2019, and the source of P was apportioned based on the principle of river base flow. The results showed that in the past 18 years, the concentrations and fluxes of total phosphorus (TP) and particulate phosphorus (PP) at Zhutuo section in the wet season were higher than those in the level and dry seasons; the rule of positive correlation between PP and SS concentrations remained unchanged. From 2002 to 2019, the concentrations and fluxes of TP, PP, and dissolved P (DP) generally increased first and then decreased, and the operation of the Xiangjiaba Reservoir was a time node for the trend turning. Compared with that in the period from 2002-2012, the SS concentration and flux decreased by 94% and 77%, TP and PP concentrations decreased by 46% and 70%, and TP and PP fluxes decreased by 58% and 74%, respectively, during 2014-2019. The decline mainly occurred in the wet season, followed by that in the level season. After the formation of the two reservoirs, the relationship between water and sediment and the form of P greatly changed, and the proportion of DP in TP increased significantly, whereas the proportion of PP was the opposite. The TP pool in overlying water in the dry and level seasons shifted from mainly particulate to mainly dissolved. The change in water and sediment conditions was the main driving force for the significant change in P concentration, flux, and form. Before the operation of the Xiangjiaba Reservoir, the Jinsha River was the maximum contributor to the whole and diffuse source part of the TP load at Zhutuo section among the contributing catchment sub-basins; however, the Minjiang River became the largest contributor after the operation. The average TP load at Zhutuo section from 2017-2019 was 3.575×104 t·a-1 (after deducting the natural background value), of which the contribution of diffuse sources and point sources accounted for 68% and 32%, respectively. The Minjiang River represented 49%, 43%, and 62% of the total TP load, diffuse source TP load, and point source TP load at Zhutuo section, respectively. Considering the load contribution and pollution intensity, the key area for P pollution control in the area upstream of the Three Gorges Reservoir was the Min-Tuo River Basin.

Inhibition of autophagy enhances the radiosensitivity of nasopharyngeal carcinoma by reducing Rad51 expression.

Radiotherapy has long been considered as the mainstay of treatment for nasopharyngeal carcinoma (NPC). However, locoregional recurrence or distant metastasis may occur in some patients due to the radiation resistance of cancer cells. Autophagy plays a vital role in protecting cells against radiation. However, the mechanism of autophagy in radiation therapy remains obscure. In the present study, we demonstrated that suppression of autophagy related 5 (Atg5) aggravated ionizing radiation (IR)-induced DNA damage and apoptosis in human NPC cells without accelerating the cell cycle, whereas regulation of the cell cycle has been widely regarded as the most important determinant of IR sensitivity. Further study showed that inhibition of autophagy suppressed the mRNA expression of Rad51, a key protein of homologous recombination that has been demonstrated to play a critical role in the repair of DNA double-strand breaks induced by radiation. Moreover, suppression of Atg5 had no impact on the radiosensitivity when cells were pre-treated by the Rad51 inhibitor, and the enhanced radiosensitivity by Atg5 suppression was reversed by overexpression of Rad51 in human NPC cells. Our results suggest that inhibition of autophagy enhances the susceptibility of NPC cells to radiation by reducing Rad51 expression. Therefore, Rad51 targeted therapy may be investigated as a potential novel agent for the adjuvant treatment of traditional radiation of NPC.

[Study on treatment of simulant dairy processing wastewater using FCR multilevel contact oxidation system].

This study applied new helical-fibrous fillers as carrier to treat simulant dairy industrial wastewater in order to improve the ability of nitrogen removal and decontamination. Based on multilevel oxidation system where the food chain was formed by different kinds of microbe, removal ratio and removal mechanism of COD, TN, NH4+ -N, TP under different HRT and effect of sludge reduction were discussed. When COD of influent was 842-1843 mg/L, TN concentration was 36.3-92.2 mg/L, NH4+ -N concentration was 30.1-52.1 mg/L, and HRT was 6h, the removal ratio of COD, TN and NH4+ -N was 93.3%, 73.3% and 80.7% respectively. COD, TN and NH: -N for effluent was 79.4 mg/L, 9.6 mg/L and 6.1 mg/L, both bellow the first degree of Integrated Wastewater Discharge Standard (GB 8978-2002). This system not only could remove nitrogen effectively, but also discharged little excessive sludge, and the average sludge production was 7.7%. It shows that this system could be conveniently operated and be used in the long term with low cost, and could be used in treating municipal wastewater and high concentration organic wastewater such as restaurant wastewater and food industry wastewater.

[Phase II clinical trial of home-produced Nedaplatin in treating advanced esophageal carcinoma].

BACKGROUND & OBJECTIVE: Nedaplatin is a second-generation anticancer drug containing organic platinum. Clinical researches in overseas showed that Nedaplatin is an anticancer drug with broad spectrum and high efficiency, especially in treating esophageal carcinoma. But the therapeutic efficacy and toxicity of home-produced Nedaplatin in China are unclear. This study was to evaluate the efficacy of home-produced Nedaplatin in China on esophageal carcinoma, and observe its toxicity. METHODS: A multi-center, phase II, prospective clinical trial was conducted. Naive patients with esophageal carcinoma were enrolled and randomized into trial group and control group. The patients in trial group were treated with home-produced Nedaplatin plus 5-fluorouracil (5-FU); the patients in control group were treated with cisplatin (DDP) plus 5-FU. RESULTS: A total of 52 patients were enrolled: 30 in trial group, and 22 in control group. For trial group, therapeutic efficacy was evaluable in 27 cases, and toxicity was evaluable in all cases; for control group, therapeutic efficacy and toxicity were evaluable in all cases. The response rate was significantly higher in trial group than in control group (29.62% vs. 22.72%, P<0.05). The complete remission (CR) rates were 18.51% in trial group and 4.55% in control group. When considering myelosuppression, the occurrence rate of anemia was similar in the 2 groups; but the occurrence rates of neutropenia and thrombocytopenia were higher in trial group than in control group, especially for grade III-IV thrombocytopenia (20.68% vs. 0%, P<0.01). The occurrence rate of gastrointestinal reaction was lower in trial group than in control group. There were no significant differences in hepatotoxicity, renal toxicity, heart toxicity, peripheral nerve toxicity, and alopecia between the 2 groups. CONCLUSIONS: Nedaplatin is an effective platinum drug for esophageal carcinoma. The treatment efficacy of Nedaplatin plus 5-FU regimen is better than that of DDP plus 5-FU regimen. It has a good clinical tolerance. The main toxicity is myelosuppression, and thrombocytopenia is predominant.

[Treatment of mix gas containing butyl acetate, n-butyl alcohol and phenylacetic acid from pharmaceutical factory by bio-trickling filter].

The bio-trickling filter packed with ZX02 stuffing is used to treat the mix gases containing butyl acetate, n-butyl alcohol and phenylacetic acid(BBP), which are discharged from Penicillin workshop of Pharmaceutical Factory. The reactor was operated for 110 days to investigate the effect of influent load, retention time and spray water on the removal of BBP and the biodegradation characteristics. The reactor displayed preferential utilization of BBP, when the maximum influent load of BBP were 229.5g/(m3 x h), 275.4 g/(m3 x h) and 42.5g/(m3 x h), the removal efficiencies were 96%, 95% and 100% respectively. The results show that the bio-trickling filter can effectively treat the mix gases and the optimum parameters were as followed: retention time was 31.2 s, the volume of spray water was 4 L/(L x d). The bio- trickling reactor has strong ability to resist shock of high influent load and resistance is maintained at low value, what's more, it doesn't need to carry out back washing frequently. With all these advantages it can be operated steadily for long time.

[Phase II clinical trial of nedaplatin in advanced non-small cell lung cancer].

BACKGROUND & OBJECTIVE: The aim of this study was to observe the efficacy and the side effects of nedaplatin in treatment of non-small cell lung cancer (NSCLC). METHODS: This is a multi-center phase II clinical trial. The previously chemotherapy treated patients with NSCLC were administrated nedaplatin alone. Nedaplatin was given at 100 mg/m2, i.v., repeated every 3 weeks. The chemonaive patients with NSCLC were randomized to two groups. The combination trial group was given with nedaplatin + vindesine regimen, and the combination control group with cisplatin + vindesine. RESULTS: Of 138 patients, 16 were in the nedaplatin single drug group; 60 were in the combination trial group; and 62 were in the combination control group. All of the 16 cases in the single drug group, which were treated with platinum previously, achieved 12.5% of response rate. And the combination trial group and control group had a very similar response rate, which were 26.7% versus 25.8%, respectively. The incidence rates of neutropenia and anemia were similar in the two groups. But the incidence rate of thrombocytopenia was higher in the trial group than that in the control group. Nedaplatin has a possibility to result in mild nausea/vomiting. CONCLUSION: Nedaplatin is an effective platinum drug in the treatment of NSCLC, not only for no previously chemotherapy patients, but also for those patients resistant to cisplatin/carboplatin. Nedaplatin has a good clinical tolerance. And the main adverse reaction was myelosuppression, especially thrombocytopenia.