[Study on lung injury induced by rare earth samarium oxide particles in rats].

Objective: To study the effect of samarium trioxide (Sm(2)O(3)) particles on rat lung tissue and compare it with the same dose of silica (SiO(2)) particles, in order to find the reference index for early screening of pneumoconiosis. Methods: In October 2018, 72 SPF healthy male rats were randomly divided into control group, SiO(2) group and Sm(2)O(3) group. The lungs of rats in each group were perfused with 2.0 ml/kg normal saline and 280 mg/kg SiO(2) and Sm(2)O(3) particle suspension by one-time non exposed tracheal perfusion. The lungs of rats were stained with hematoxylin eosin (HE) staining, and the pathological changes of lung tissues were observed. The concentrations of SNAIL homologue 1 (SNAI1) , SNAIL homologue 2 (SNAI2) , and heat shock protein-27 (HSP-27) in rat serum were detected by enzyme-linked immunosorbent assay. 0.5 g of lung tissue from rats in Sm(2)O(3) group and control group exposed to dust for 56 days was screened for long-chain noncoding RNA (lncRNA) and circular RNA (circRNA) . Results: After 7 days of dust exposure, the alveoli in SiO(2) group and Sm(2)O(3) group were disordered, and lymphoid tissue aggregation and proliferation were observed around the bronchial wall. At 14 days, a large number of lymphocytes infiltrated in SiO(2) group, and a small number of macrophages containing Sm(2)O(3) and fibrotic nodules scattered in Sm(2)O(3) group. At 28 days, a small amount of lymphocyte infiltration appeared in SiO(2) group, and fibrotic nodules were seen in some areas of Sm(2)O(3) group. At 56 days, there was a small amount of fibroblast proliferation in SiO(2) group, and a large number of fibrotic nodules containing gray black matter were seen in Sm(2)O(3) group. There was no significant difference in lung organ coefficient among groups at different dust exposure time (P>0.05) . After 14 days of dust exposure, the contents of SNAI1 and SNAI2 in serum of rats in SiO(2) group were lower than those in control group, the content of SNAI2 in serum of Sm(2)O(3) group was lower than that in control group, and the contents of SNAI1 and SNAI2 in serum of Sm(2)O(3) group were higher than those in SiO(2) group (P<0.05) . The content of HSP-27 in SiO(2) group was lower than that in control group (P<0.05) . After 56 days of dust exposure, the content of HSP-27 in Sm(2)O(3) group was lower than that in control group (P<0.05) . At 56 days, lncRNA in Sm(2)O(3) group was up-regulated by 148 and down regulated by 725, circRNA was up-regulated by 16 and down regulated by 153. Conclusion: Sm(2)O(3) can cause lung injury in rats, and the change of SNAI2 content can be detected in the early stage, which can be used as a reference index for early screening of pneumoconiosis. There are differences in the expression of lncRNA and circRNA after 56 days of dust exposure in rats, which may be related to the pathogenesis of pneumoconiosis.

Advanced phosphorus removal for secondary effluent using a natural treatment system.

Mechanisms for low concentrations phosphorus removal in secondary effluent were studied, and a process was developed using limestone filters (LF), submerged macrophyte oxidation ponds (SMOPs) and a subsurface vertical flow wetland (SVFW). Pilot scale experimental models were applied in series to investigate the advanced purification of total phosphorus (TP) in secondary effluent at the Chengjiang sewage treatment plant. With a total hydraulic residence time (HRT) of 82.52 h, the average effluent TP dropped to 0.17 mg L(-1), meeting the standard for Class III surface waters. The major functions of the LF were adsorption and forced precipitation, with a particulate phosphorus (PP) removal of 82.93% and a total dissolved phosphorus (TDP) removal of 41.07%. Oxygen-releasing submerged macrophytes in the SMOPs resulted in maximum dissolved oxygen (DO) and pH values of 11.55 mg L(-1) and 8.10, respectively. This regime provided suitable conditions for chemical precipitation of TDP, which was reduced by a further 39.29%. In the SVFW, TDP was further reduced, and the TP removal in the final effluent reached 85.08%.

Expression levels of HER2 and MRP1 are not prognostic factors of long-term survival in 829 patients with esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is the eighth most frequent neoplasm in China. However, the expression levels of human epidermal growth factor receptor 2 (HER2) and multidrug resistance protein 1 (MRP1) in patients with ESCC remain to be determined. In the present study, 829 ESCC cases were evaluated using immunohistochemistry. The association between the expression levels of HER2 and MRP1 and the patient's clinicopathological factors was analyzed using Fisher's exact test or χ2 test. Univariate analysis was performed via Kaplan-Meier survival curves, while the Cox proportional hazard model was used for multivariate analysis. A significant correlation was observed between the expression levels of HER2 and the patient's gender (P<0.050), tumor size (P=0.013) and venous/lymphatic invasion (P=0.039). However, no significant correlation was identified between the expression levels of MRP1 and the clinicopathological factors of the patients. In univariate analysis, gender, differentiation, depth of invasion, clinical stage, adjuvant radiotherapy or chemotherapy and lymph node metastasis were significantly correlated with progression-free survival (PFS) and overall survival (OS) in patients with ESCC (P<0.050). The graphical representation of the Kaplan-Meier estimate curves suggested that the expression levels of HER2 or MRP1 did not exert any influence on prognosis (log-rank test, P>0.050). In multivariate analysis, tumor location, gender, clinical stage, differentiation and lymph node metastasis were identified as independent factors of prognosis in patients with ESCC (P<0.050). However, the expression levels of HER2 or MRP1 were not independently associated with PFS or OS in these patients. In conclusion, the present large-scale study demonstrates that the protein expression levels of HER2 and MRP1 does not exert any influence on the prognosis of ESCC.