Objective To investigate the drinking water quality in the countryside in different river systems areas in Hefei, China and to provide scientific data for the improvement of drinking water quality and protection of human health. Methods In Hefei, according to hydrological geology, the rural areas were classified into the Lake-Chaohu river system, the Huaihe-River river system, the Yangtze-River-Huaihe-River watershed area and the general area, the multi-stages sampling method were employed in the investigation of water quality. Results 82.15% of local people drank the shallow-layer well water. 82.73% of water wells exposed to a pollution source which was no more than 30 meters from the well. Dissolved total solid and total coliforms were higher in the rainy season compared with that in the dry season, but the content of the other contaminants were higher in the dry season. Among the river systems areas, the content of some contaminants showed a significant difference. When the distance of pollutant source was fixed, increasing the well depth could reduce the bacterium count in water. Conclusion In the countryside of Hefei, the total bacteria count and the total coliforms in drinking water greatly exceed the allowed limits, water supply improvement should be made according to the local hydrological and geological condition.

It was a retrospective cohort study. Patients diagnosed with idiopathic membranous nephropathy (IMN) and received rituximab (RTX) alone for one course of treatment during hospitalization in the Department of Nephrology of the First Hospital of Jilin University from March 2020 to March 2022 were enrolled. The patients were divided into 1 g standard treatment group (once 1 g every 2 weeks for twice) and 375 mg/m 2 experimental treatment group (375 mg/m 2 once a week for 4 weeks) according to the different methods of drug administration, and the efficacy and safety of different doses of RTX in the treatment of IMN were compared between the two groups to provide a reference for optimizing the clinical treatment protocol. The patients were followed up regularly for more than 9 months after treatment and the data were complete. A total of 69 patients were included with age of (51.7±11.8) years old, and 46 males (66.7%). There were 31 patients in the 1 g standard treatment group and 38 patients in the 375 mg/m 2 experimental treatment group. The proportion of first-treatment patients in the 1 g standard treatment group was higher than that in the 375 mg/m 2 experimental treatment group (87.1% vs. 65.8%, χ2=4.174, P=0.041). There were no statistically significant differences in the general data, clinical characteristics and baseline laboratory parameters between the two groups (all P>0.05). At the end of 3 months of treatment, 22 patients (31.9%) experienced remission, including 9 patients (29.0%) in the 1 g standard treatment group and 13 patients (34.2%) in the 375 mg/m 2 experimental treatment group ( χ2=0.211, P=0.646). At 6 months, 30 patients (43.5%) experienced remission, including 12 patients (38.7%) in the 1 g standard treatment group and 18 patients (47.4%) in the 375 mg/m 2 experimental treatment group ( χ2=0.521, P=0.470). At 9 months, 38 patients (55.1%) achieved remission, including 18 patients (58.1%) in the 1 g standard treatment group and 20 patients (52.6%) in the 375 mg/m 2 experimental treatment group ( χ2=0.204, P=0.652). At 9 months, the 24 h urine protein of 1 g standard treatment group and 375 mg/m 2 experimental treatment group decreased by 7.93 (6.24, 8.46) g and 7.45 (5.66, 8.67) g (both P<0.05), respectively, and serum albumin increased by 16.4 (15.5, 17.5) g/L and 15.5 (9.0, 15.8) g/L (both P<0.05), respectively, from the baseline value. Kaplan-Meier survival analysis result showed that there was no significant difference in the time of phospholipase A2 receptor titer decreasing to <5 RU/ml between the two groups (Log-rank χ2=3.653, P=0.056). Twenty-three non-serious adverse events occurred in the 1 g standard treatment group, involving 16 patients, and 10 non-serious adverse events occurred in the 375 mg/m 2 experimental treatment group, involving 10 patients. There was better safety in the 375 mg/m 2 experimental treatment group than that in the 1 g standard treatment group ( Fisher value=8.593, P=0.015). Both 375 mg/m 2 regimen and 1 g regimen of RTX in IMN patients are effective in relieving proteinuria and elevating serum albumin. The 375 mg/m 2 regimen of RTX has a lower incidence of adverse events compared with the 1 g regimen.