Objective:To investigate the epidemiological characteristics and transmission chain of COVID-19 in two families, and to provide scientific evidence for effective prevention and control measures.Methods:Field epidemiological investigation was conducted for the COVID-19 cases occurred in two families and the close contacts in a county of Baotou city in Inner Mongolia Autonomous Region. Descriptive statistical analysis on epidemiological data was conducted.Results:The infection source of the COVID-19 cases in the two families was a man who had living history in Wuhan. After his return, his parents were infected by him. A few days later, the members of a neighbor family were found to be infected, and relatives of this family were also infected after dining together repeatedly. Finally, ten confirmed cases and three suspected cases of COVID-19 were detected in the two families.Conclusions:Human-to-human transmission of COVID-19 can occur not only in a family but also in neighborhoods. The cases in two families had close relationship, indicating the necessity to strengthen the health education about COVID-19 prevention and control and the management of groups at high risk to reduce the incidence of COVID-19 in families and neighborhoods.

OBJECTIVE： To study the dose-time-effect relationship of Tibetan medicine Rannasangpei in cerebral ischemic- reperfusion injury model rats with intragastric administration. METHODS： The rats were randomly divided into sham operation group （normal saline， 10 mL/kg）， model control group （normal saline， 10 mL/kg）， positive control group （nimodipine， 30      mg/kg）， Rannasangpei different dose groups （0.52， 1.04， 2.08， 4.17， 8.33， 16.67， 33.34， 66.68， 133.36， 266.72 and 533.44    mg/kg）， with 18 rats in each group. Each group was given relevant medicine intragastrically once； 25 min after intragastric administration， cerebral ischemic-reperfusion injury model was established with suture-occluded method in those groups except for sham operation group. 24， 48， 72 h after cerebral ischemia， neuroethology of rats were graded in each group. The rate of cerebral infraction was detected to evaluate the optimal effective time， the optimal dose （Dmax） and maximal effect （the rate of minimum cerebral infraction， Emax） of Ratnasampil at different periods of cerebral ischemia. Dose-time-effect relationship of Rannasangpei dose with the rate of cerebral infraction was fitted with Thermo Kinetica 5.1 software. The area under curve （AUClast） and retention dose （MRTlast） of dose-effect curve were calculated， and detect the levels of SOD and MDA. RESULTS： Compared with sham operation group， the neurobehavior of model group was significantly abnormal （P＜0.05 or P＜0.01）， and the rate of cerebral infarction was significantly increased （P＜0.01）； the level of SOD was decreased significantly （P＜0.01， 48 h）， and the level MDA was increased significantly （P＜0.05， 48 h）. Compared with model control group， there was no significant change in neurobehavioral abnormalities in the nimodipine group （P＞0.05）， and the rate of cerebral infraction was decreased significantly （P＜0.01， 24， 48 h）. The level of SOD in rats were increased significantly （P＜0.01， 48 h）， while the level MDA decreased significantly （P＜0.05， 48 h）. Rannasangpei 2.08-33.34 mg/kg could significantly improved neurobehavioral abnormalities （P＜0.05， 24 h）； 24 h after cerebral ischemia， the rate of cerebral infraction was decreased significantly in Rannasangpei 4.17-133.36 mg/kg group （the lowest is 33.34 mg/kg group， P＜0.05 or P＜0.01）. The level of SOD in rats were increased significantly in 33.34-533.44 mg/kg groups （P＜0.05）. the level MDA was decreased significantly in 0.52-2.08， 8.33， 33.34， 266.72 and 533.44 mg/kg groups （P＜0.05）. Dmax was 33.34 mg/kg， Emax was 3.02％， AUClast was 5 141.76 mg/kg and MRTlast was 329.161 mg/kg. 48 h after cerebral ischemia， the rate of cerebral infraction was decreased significantly in Rannasangpei 2.08-133.36 mg/kg groups （the lowest is 66.68 mg/kg group， P＜0.05 or P＜0.01）， while the level of SOD was increased significantly in 1.04-533.44（except for 4.17）mg/kg groups （P＜0.05）. The level of MDA was decreased significantly in 16.67-66.68， 533.44 mg/kg groups （P＜0.05）， Dmax was 66.68 mg/kg， Emax was 2.13％， AUClast was    5 219.36 mg/kg and MRTlast was 340.521 mg/kg. 72 h after cerebral ischemia， the rate of cerebral infraction and the level of MDA had no significant decreased in Rannasangpei groups （P＞0.05）， and the levels of SOD had no significant increase （except for 0.52 mg/kg group， P＞0.05）. CONCLUSIONS： The optimal effective time of Rannasangpei for the treatment of cerebral ischemia-reperfusion injury in rats is 48 h， and the Dmax is 66.68 mg/kg. The improvement mechanism may be related to increase the level of SOD and decrease the level of MDA.

[Objective]To investigate the prognostic value of 18F-FDG PET/CT with different metabolic parameters in newly diagnosed limited-disease(LD)small cell lung cancer(SCLC).[Methods]Retrospective analysis was carried out in the patients between June 2005 to December 2016 in our hospital confirmed of LD SCLC by pathology or cytology and comprehensive imaging. Fifty-four patients were recruited. Record the general characteristics of patients,pre-treatment KPS score,smoking status,weight loss,serum LDH,NSE,OS,PFS. All lesions(primary lesions + metastases)were sketched out within one VOI,and the SUVmax, SUVmean and SUVpeak in the VOI were automatically measured and recorded. The automatic measurement was performed by the fixed threshold method. The thresholds of tumor of MTV and TLG were 40% and 50% of SUVmax. The TLG and MTV were identified as TLG40%,TLG50%,MTV40% and MTV50% respectively. Kaplan-Meier method was used for survival analysis. All the prognostic factors were analyzed by Cox model.[Result]The median SUVmax was 13.92(2.61~43.28),the median of SUVmean was 8.31(1.71~26.85) and the median of SUVpeak was 10.51(1.49 ~ 27.48). The median of TLG40% was 340.22(16.58 ~ 2827.26),the median of TLG50%was 215.645(1.70 ~ 2270.36),the median of MTV40% was 36.71(1.15 ~ 259.47 cm3),the median of MTV50% was 19.65(0.93 ~1900.00)cm3. Univariate and multivariate analysis of metabolic index and prognosis showed that TLG50% was the prognostic factor of OS(P = 0.013),but not of PFS(P > 0.05). The SUVmax,SUVmean and SUVpeak were not the prognostic factors of OS and PFS(P >0.05).[Conclusion]The volume metabolic parameters TLG50%was the independent prognostic factor of the overall survival time of the LD SCLC. The volume metabolic parameters (TLG and MTV) of 18F-FDG PET/CT were related to the prognosis of SCLC ,which could provide the basis for individual chemotherapy.

Objective To evaluate the value of 18 F-FDG PET/CT imaging in predicting the progno-sis of newly diagnosed SCLC with normal serum LDH ( SCLC-nsLDH) . Methods A total of 68 SCLC pa-tients (59 males, 9 females, median age:58.5 years) proved by pathology between June 2005 and Decem-ber 2016 were retrospectively analyzed. All patients underwent 18 F-FDG PET/CT. The general information of patients, including LDH, NSE, OS, PFS and SUVmax , were recorded. SUVmax differences were analyzed with Mann-Whitney u test. Life-table method and Kaplan-Meier analysis were used to estimate the survival rate and median survival time. The survival function curve was drawn. Log-rank test was used to analyze whether there existed statistical differences in survival period among different groups. Cox regression analysis was used for screening the influencing factors of prognosis. Results ( 1) In 68 SCLC patients, there were 38 cases with limited disease ( LD) and 30 cases with extensive disease ( ED) . There were 3 cases in stageⅠ, 7 cases in stage Ⅱ, 29 cases in stage Ⅲ, 29 cases in stage Ⅳ. The median SUVmax of the primary tumor was 11.35 (9.90, 13.90). There was no significant difference between the median SUVmax of LD group and that of ED group:11.05(9.72, 13.60) vs 12.25(10. 05, 14.12)months;z=-0.797, P=0.426. The median serum LDH was 195.15(171.00, 220.80) U/L. (2) The median follow-up time was 18(range:2-101) months. The disease developed in 46 patients and 35 patients died. The median OS was 23 (95%CI:13.3-32.7) months and median PFS was 17 (95% CI: 11.4-22.6) months. (3) ROC curve showed the optimal SUVmax cutoff value was 10.85. The OS of patients with SUVmax≤10.85 ( n=25) and with SUVmax>10.85 (n=43) were 40.0(95% CI:2.5-77.5) months and 18.0(95% CI:13.3-22.7) months(χ2=8.956, P=0.003), respectively. (4)Weight loss, VALG stage and primary tumor SUVmax were independent prog-nostic factors for OS (all P<0.05). Only VALG stage was an independent prognostic factor for PFS (P<0. 001) . Conclusion 18 F-FDG PET/CT can help to differentiate the different prognosis of SCLC-nsLDH patients, and provide more evidence for the choice of individual treatment strategy.

Objective:To evaluate the quantity and function changes of dendritic cells ( DC) in peripheral blood of patients with repeated implantation failure ( RIF).Methods:30 patients with RIF and 15 normal controls were enrolled in this study,and the peripheral blood was collected during the mid-luteal phase.The percentage of DC subsets and the expression levels of functional molecules were assessed by flow cytometric analysis.Results:Compared with normal controls,the percentage of lin-HLA-DR+DC cells accounting for leukocytes in patients with RIF was not significantly different ( P>0.05).There were also no significant differences in the expression levels of co-stimulatory molecules ( CD80 and CD86) and immune tolerant molecules CD200 on DC cells surfaces between patients with RIF and normal controls ( all P>0.05).In addition,the percentage of CD11c+CD123-mDC accounting for DC cells was significantly increased in patients with RIF (P<0.05),however,the percentage of CD11c-CD123+pDC was similar (P>0.05). Conclusion:The percentage of mDC accounting for DC cells was significantly increased in patients with RIF, which may be one of factors affecting pregnancy outcomes.

Objective To evaluate the apical sealing ability of iRoot SP root canal sealer in oval-root canal. Methods After root canals were instrumented by Mtwo, 28 premolars with oval-root canal were randomly divided into 2 groups, 14 teeth in each. The root canals were obturated with AH Plus (group A) and iRoot SP (group B) by modified continuous wave condensation technique. The apical leakage was evaluated by dye penetration method and transparent teeth technique. Results Mean depth of leakage was (0.92 ± 0.26) mm for group A and (0.84 ± 0.40) mm for group B. There was no significant difference between the two groups (t=0.506, P > 0.05). Conclusion The apical sealing ability of iRoot SP is equivalent to AH Plus in oval-root canal.

AIM: To study mitochondrial mass and structural protein changes in dexamethasone (DEX)-mediated mouse thymocyte apoptosis process. METHODS: DEX-induced mouse thymocyte apoptosis model was established. Annexin V-FITC/PI double staining was used to identify apoptotic and necrotic cells by flowcytometry, JC-1 staining was adopted to test mitochondrial membrane potential (△?_m), and cellular structural protein changes were studied with CFDA-SE staining. RESULTS: By 1?10~(-6) mol/L DEX stimulation, the apoptotic rate was 51.25%?5.51% and had significantly difference from control group (12.03%?2.00%); the necrotic rate in DEX group was 30.25%?3.67% and also had significantly difference from control group (10.11%?1.11%, P

0.05) compared with control group at 1 h and 3 h; while ~FL 1 in DEX group at 5 h (660.91?72.95) was significant lower (P

AIM: To study the changes of mitochondrial membrane potential(△?m) and mitochondrial mass in apoptosis of Jurkat cells induced by camptothecin(CPT).METHODS: Jurkat cells were treated with CPT.Annexin V-FITC/propidium iodine(PI) double stainig was used to detected early stage of apoptosis and PI staining for analyzing the cell cycle.Jurkat cells were stained by annexin V-PE/DiOC_6(3) to detect changes of △?m.The mitochondrial mass was measured by cytometry with NAO staining.RESULTS: 6 h after treated with 10 ?mol/L CPT,the rate of early apoptotic cells(22.59?1.04)% had significantly difference compared with control group(3.93?0.73)%(P0.05).Apoptotic peak appeared obviously after treated with CPT,the percentage of late apoptotic cells(13.58?0.97)% had distinctly difference compared with control group(3.18?0.51)%(P

It was found that the proliferation of mice L7712 leukemic cells in vitro was markedly inhibited by 5 mg/L GP1 and VP10 The inhib itory rate increased with the incubation time. At a concentration of 0 .04-20mg/L, the mitotic index ( MI ) of GP1 group increased, but the MI of VP16 group decreased. After L7712 cells were treated with GP, 5 mg/L for 12 h the MI reached the highest point which was 8 times as high as that of the control, at the same time, the MI of VP16 ( 5 mg/L) group was about one-third of that of the control. The result of the combination of GP1 with VP16 showed that VP16 could antagonize the effect of GP on MI of L7712 cells. After being treated by GP1 and VP18 for 24 h, serious damage of L7712 cells could be observed. Both drugs inhibited the incorporation of (3H) TdR into DNA of S180, ascitic hepatoma (AH), L1210 and L7712 cells incubated for 24 h. It was further observed that S180 and L7712 cells were more sensitive than other cells to both drugs.