Objective To investigate clinical characteristics of patients with ST-elevation myocardial infarction (STEMI) and hypokalemia and the effects of hypokalemia on prognosis. Methods Consecutive 216 cases with STEMI who underwent emergency PCI were divided into group A (serum potassium ＜ 3.5 mmol/L) and group B (serum potassium＞3.5 mmol/L). Infarct site, infarct interrelated artery, peak level of CK-MB and cTnT were compared between two groups. Post-infarctional angina pectoris, arrhythmia, heart failure and cardiac death were compared. Results (1 )The percentage of anterior wall myocardial infarction , left anterior descending artery (LAD) lesions in group A were significantly higher than those in group B [61.2%(41/67) vs. 44.3%(66/149),55.2%(37/67)vs. 38.9%(58/149),P = 0.022,0.026]. The peak levels of CK-MB and cTnT in group A were significantly higher than those in group B [(194.39 ± 101.27) μg/L vs. (115.35 ±78.62)μg/L,(19.16 ±11.48)μg/L vs. (9.07 ±7.65) μg/L,P = 0.004,0.002].(2)Left ventricular ejection fraction in group A was significant lower than that in group B (P - 0.003). The incidence rates of post-infarctional angina pectoris, ventricular tachycardia, ventricular fibrillation and heart failure were significantly higher in group A [43.3%(29/67),32.8%(22/67), 11.9%(8/67),37.3%(25/67)] than those in group B [24.8%(37/149),18.1%(27/149),4.0%(6/149),20.8%(31/149)](P = 0.006, 0.017, 0.029, 0.010). Conclusions Hypokalemia is associated with infarct site and infarct interrelated artery. Hypokalemia has bad effect on prognosis of STEMI.

Objective To establish a method for the determi nation of emodin and chrysophanic acid in Compound Rhubarb Spray by HPLC.Methods The ODS column was applied.methanol∶water(87∶13)served as mobile phase.The detectio n wavelength was at 254nm and the flow r ate was 0.65ml /min.Results The average recovery of emodin was 99.48%with relative standard deviation being 1.75%(n=9)and the average recovery of chrysoph anic acid was 101.46%with rela-tive standard deviation being 2.85%(n=9).Conclusion The method was simple,rapid and reli able.It is suitable for the quality control of Compound Rhubarb Spray.

Objective: To forecast the risk distribution of inter-animal plague in Meriones unguiculatus effectively and provide scientific evidence for prevention and control of inter-animal plague, through studying the correlation between meteorological and environmental factors and inter-animal plague in Meriones unguiculatus. Methods: Positive data of plague bacterial culture in 30 epidemic source areas of Meriones unguiculatus in the Inner Mongolia plateau from 2005 to 2018, including detecting time, number of bacteria, latitude and longitude or detailed location, host type, were from the Chinese Disease Prevention and Control System Plague Prevention Management Information System and related professional institutions for plague prevention and treatment. Logistic regression was used to explore the relationship between the inter-animal plague and climate-related risk factors. The Maximum Entropy (Maxent) model was used to predict the habitat distributions of inter-animal plague, and the receiver operating characteristic (ROC) curve was used to validate the model. Results: There were 11 climatic factors including annual mean temperature, isothermality, temperature seasonality, mean temperature of driest quarter, mean temperature of warmest quarter, mean temperature of coldest quarter, annual precipitation, precipitation seasonality, globcover, normalized difference vegetation index and slope, were related to the outbreak of plague among Meriones unguiculatus and included in the model (OR = 1.302, 0.455, 0.957, 0.930, 4.864, 0.179, 0.986, 1.126, 0.992, 0.981, 0.721, P < 0.01). The increase of annual mean temperature, mean temperature of warmest quarter and precipitation seasonality will increase the risk of animal plague in the plague foci of Meriones unguiculatus; the increase of isothermality, temperature seasonality, mean temperature of driest quarter, mean temperature of coldest quarter, annual precipitation, globcover, normalized difference vegetation index, and slope will reduce the risk of animal plague in the plague foci of Meriones unguiculatus. The areas under the curve (AUCs) of the Maxent model training data and test data were 0.988 and 0.985, the prediction effect of the model was better. The habitat distribution of Meriones unguiculatus plague mainly concentrated in the central and northern Ulanqab plateau, Ordos plateau, and eastern Hetao plain. Conclusions The use of Maxent model and climate data can predict the potential risks and spatial distribution of animal plague in Meriones unguiculatus; the results are accurate and reliable.

Objective To investigate the mechanism of implanted tissue-engineered bone (TEB)recruiting endogenous mesenchymal stem cells (BMSCs) towards bone regeneration after traumatic bone defect.Methods In vivo experiments:2 mm of diaphysis and periosteum were removed from the middle of the femoral shaft in 8 week old FVB/N mice to form a large segment of bone defect.Demineralized bone matrix (DBM) and TEB were implanted into the defect area and fixated.All mice were randomly divided into DBM group (n =18) and TEB group (n =18).The results were observed 24 hours after implantation:(1) flow cytometry was used to evaluate the number of mobilized host BMSCs into the blood;(2) non-invasive bioluminescent imaging was used to observe the ability of two groups in recruiting mouse bone marrow derived mesenchymal stem cells (mBMSCs) in peripheral blood to the defect area;(3) ELISA was used to evaluate the stromal cell-derived factor 1 (SDF-1) content in peripheral blood of two groups.In vitro experiments:(1) transwell assay was conducted to evaluate the ability of SDF-1 (100 ng/ml) in promoting the migration of human bone marrow derived mesenchymal stem cells (hBMSCs).SDF-1/C-X-C motif chemokine receptor-4 (CXCR4) pathway was blocked by the selective CXCR4 antagonist Plerixafor (AMD3100).The experimental groups were divided into control group,SDF-1 group,and SDF-1 + AMD3100 group.(2) The co-culture system of human umbilical vein endothelial cells (hUVECs) and hBMSCs was established,and cells were stimulated by SDF-1.The experimental groups were divided into hBMSCs group,hBMSCs + hUVECs group,and hBMSCs + hUVECs (AMD3100 pretreatment) group.Transwell assays were used to compare the migration of hBMSCs in each group.ELISA was used to detect the concentration of hepatocyte growth factor (HGF) in the co-culture supernatant.(3) In vitro cultured hUVECs were stimulated by SDF-1 and SDF-1/CXCR4 pathway was antagonized by AMD3100.The experimental groups were divided into control group,SDF-1 group,and SDF-1 + AMD3100 group.Quantitative real-time polymerase chain reaction (qRT PCR) was used to evaluate the expression of HGF in each group.Results In vivo experiments:24 h after transplantation,the number of BMSCs and SDF-1 concentration in the TEB group were significantly highcr than those in the DBM group (P ＜ 0.05).The number of recruited mBMSCs into the circulation in the TEB group was larger than that in the DBM group (P＜ 0.01).In vitro experiments:(1) compared with the control group and the SDF-1 + AMD3100 group,the SDF-1 group significantly enhanced the migration ability of hBMSCs in Transwell migration experiments (P ＜ 0.01);(2) compared with the hBMSCs group and the hBMSCs + hUVECs (AMD3100 pretreatment) group,the number of migrated cells and HGF concentration in the hBMSCs + hUVEC group significantly increased (P ＜ 0.01),but there were no significant differences between the hBMSCs group and the hBMSCs + hUVECs (AMD3100 Pretreatment) group (P ＞0.05);(3) qRT-PCR showed that the expression of HGF was significantly increased in the SDF-1 group compared with the control group (P ＜ 0.05).After antagonizing SDF-1/CXCR4,HGF expression in the SDF-1 + AMD3100 group was significantly lower than that in the SDF-1 group.Conclusions TEB transplantation in traumatic bone defect can significantly increase the concentration of chemokine SDF-1 in vivo and effectively promote the mobilization of endogenous MSCs and recruitment of circulating MSCs.SDF-1 not only directly promotes the migration of hBMSCs through SDF-1/CXCR4 pathway,but also up-regulates the expression and secretion of HGF in vascular cells to further amplify the chemotactic effect of SDF-1 on hBMSCs.