Molecular surveillance of rubella virus in Beijing, China during 2010-2021: Progress and challenges in rubella elimination.

Rubella is listed by the World Health Organization (WHO) as a disease that needs to be eliminated worldwide. The aim of this study was to understand the progress and challenges towards rubella elimination in Beijing, China, by analyzing molecular surveillance data combined with immunization and surveillance strategies as well as epidemiological data. With high immunization coverage under the 3-dose policy (8 months, 18 months, and 6 years) and supplementary immunization activities for the floating population, rubella incidence showed a downward trend since 2010, despite two epidemics that occurred in 2014-2015 and 2019. The reported rubella cases were generally concentrated in the age group of 15-34 years. Although citywide surveillance for congenital rubella syndrome (CRS) has been carried out since 2016, only one case has been confirmed by laboratory testing. Furthermore, molecular surveillance data showed that rubella viruses (RVs) circulating in Beijing during 2010-2020 were evidently heterogeneous; the domestic lineage 1E-L1 and multiple imported lineages, including 2B-L1, 1E-L2, and 2B-L2c, were identified in the last decade. Meanwhile, two lineage-related switches were determined, including the displacement of lineage 1E-L1 with lineage 2B-L1 around 2014 and the transition between lineage 2B-L1 and lineage 1E-L2 and 2B-L2c in 2018-2019. This RV transmission pattern was similar to that observed across the country, whereas lineages 1E-L1 and 2B-L2c were prevalent in Beijing for a shorter period. Overall, these results indicate the need to maintain routine immunization with rubella-containing vaccines, promote regular supplementaryimmunizationactivities, and enhance rubella and CRS surveillance even in order to accelerate rubella elimination in Beijing. Further, the existing immunization strategies must be optimized to further close the immunity gap.

[Analysis of the results and methods on proficiency testing of determination of Fe, Mn in drinking water].

OBJECTIVE: To analyse the results and methods on proficiency testing(PT) for determination of Fe, Mn in drinking water and to discuss the influencing factors. With a view to the laboratory for accurate determination of drinking water iron and manganese to provide technical support. METHODS: 180 labs from 30 provinces (cities), autonomous regions took part in the PT. Based on methods of PT, statistical analysis of the results, to find the causes of dissatisfactory results. RESULTS: According to the results of the report for the first time, the PT showed that 85.56% labs presented satisfactory results of determination of Fe and 87.71% labs presented satisfactory results of determination of Mn. In addition to ICP/MS, it showed that 76.00%, 88.89%, 93.75% respectively presented satisfactory results of the methods of AAS, ICP-AES and chemical of determination of Fe. It showed that 79.23%, 94.29%, 72.73% respectively presented satisfactory results of the methods of chemical, AAS and ICP-AES of determination of Mn. The initial results of 37 labs had dissatisfactory. Results of statistics showed that iron, manganese at the same time [ZB] > or = 3 for the 11 labs. CONCLUSION: Most of the labs that took part in the PT have good competence in analyzing Fe, Mn. The main reasons of the dissatisfactory results were larger systematic errors, experimental blank, matrix interference and feeble control ability of the key point of the experiment.

In vitro cytotoxicity assay with selected chemicals using human cells to predict target-organ toxicity of liver and kidney.

In order to elucidate the feasibility of predicting liver and kidney target-organ toxicity using in vitro cytotoxicity assay, cytotoxicity of selected chemicals, acetaminophen (AAP), mitomycin (MMC), cupric chloride (CuCl2), phenacetin, cadmium chloride (CdCl2) and aristolochic acid (AA), was studied using human hepatoma (Bel-7402) cells and human renal tubular epithelial (HK-2) cells. Cell viability and mitochondrial permeability transition (MPT) were assessed by the neutral red (NR) assay and laser scanning confocal microscope, respectively. The results of the NR assay indicated that cytotoxicity of hepatoxicants, AAP, MMC and CuCl2 in liver cells was higher than that in kidney cells. Cytotoxicitiy of nephrotoxicant, CdCl2 was lower in liver cells than that in kidney cells, but nephrotoxicant phenacetin and AA was higher cytotoxicity in liver cells than that in kidney cells. The cytotoxicity of AAP and phenacetin was strengthened in the presence of S9 mixture, indicating that they are metabolism-mediated cytotoxicants. All selected chemicals disrupted MPT in dose-dependent manner. Linear regression analysis revealed a good correlation between the IC50 values of cytotoxicity and the EC50 values of MPT in Bel-7402 cells and HK-2 cells (R2 = 0.987 and 0.823, respectively). Cytotoxicity assay in vitro using specific cells show good compatibility with target-organ toxicity in vivo. However, limitations of in vitro cytotoxicity assay are due to its incomplete process of ADME and the defect of predicting chronic toxicity effect after long-term exposure to a chemical.