Objective To explore the correlation between the genetic dissimilarity and heterozygosity of mates and the patho?genicity of Schistosoma japonicum in the definitive host. Methods By using seven microsatellite loci markers,S. japonicum genotyping of sixteen pairs randomly mated was performed,the genetic dissimilarity and heterozygosity were calculated between the mates,and the correlation between the genetic dissimilarity and heterozygosity of the mates and the pathogenicity of S. japon?icum in the definitive host was evaluated. Results There was a significant correlation between the genetic similarity of S. ja?ponicum mates and the mean number of eggs per worm pair in the liver and intestinal tissue (r = 0.501 6 ,P < 0.05;r =0.796 5,P<0.01,respectively)and the hatching rate of deposited eggs in the liver(r=0.508 3,P<0.05),respectively. There was no correlation between the genetic similarity of the mates and hepatosplenomegaly per worm pair(r=0.109 5,P>0.05;r=0.265 3,P>0.05,respectively)and the average diameter of granuloma in the liver(r=-0.272 7,P>0.05),respec?tively. There was no correlation between the heterozygosity of the mates and all the pathological parameters of S. japonicum in the definitive host(P > 0.05). Conclusions There is the correlation between the genetic dissimilarity of the mates and the pathogenicity of S. japonicum in the definitive host,and the genetic dissimilarity is greater,pathogenicity is weaker. There is no correlation between heterozygosity of the mates and the pathogenicity of S. japonicum in the definitive host.

Objective: To conduct an epidemiological investigation on a cluster of overseas imported cases of coronavirus disease 2019(COVID-19)in Qingtian County, Lishui,so as to provide reference for the prevention and control of COVID-19 imported from abroad. Methods: According to the COVID-19 Prevention and Control Program (FiFth Edition) issued by National Health Commission of China,a field investigation was employed and the close contacts of the case were tracked down ;the real-time reverse transcription polymerase chain reaction (RT-PCR) assay was performed to detect the nucleic acid of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from the sputum specimens or throat swabs of cases;the epidemiological characteristics,source of infection,route of transmission and disposal of the cluster were analyzed. Results: From March 1 to March 6,2020,eight confirmed cases and one asymptomatic case of COVID-19 were reported. Their median age was 33 years old. The nine cases all had no fever,no decrease in leukocyte and lymphocyte levels,and the clinical symptoms of seven cases were not obvious. The asymptomatic case had been tested negative for SARS-CoV-2 for six times,but had been weakly positive for IgM antibody and strongly positive for IgG antibody. Nine cases were all the employees of the same restaurant in Begamo,Italy. They lived in three independent villas and usually had lunch and dinner in the restaurant where they worked. Begamo had COVID-19 epidemic,but the staff of the restaurant did not take any protective measures such as wearing masks and environmental disinfection. Eight cases reported to have cold symptoms in Italy during mid February. Through a closed-loop management of“all people,all sites,all chains ”,such as treatment of current cases,screening and isolation of close contacts and health education,totally 372 close contacts were traced back,yet no fever or respiratory symptoms have been found. Conclusions It was a cluster of COVID-19 cases imported from abroad. The clinical symptoms of the cases were not obvious. Qingtian County adopted the closed-loop management in time,and effectively controlled the spread of the epidemic. No second-generation cases have been found.

Objective:To investigate the effects of applying Stent Boost Subtract (SBS) technique during percutaneous coronary intervention in patients with complex coronary lesions.Methods:200 patients with coronary artery disease (CAD) who hospitalized in the department of cardiology in Guangzhou First People′s Hospital from June 2018 to June 2020 were enrolled. The coronary lesions of all patients were corresponding to B2 or C type suggested by American Heart Association (AHA)/American College of Cardiology (ACC) according to coronary angiography and treated with percutaneous coronary intervention (PCI). Patients were randomly divided into SBS group ( n=82, SBS technique was applied during PCI) and IVUS group [ n=118, intravascular ultrasound (IVUS) was applied during PCI]. After stent implantation, quantitative coronary angiography (QCA) automatic analysis system was used to measure the related parameters of stent diameter (including the minimum, maximum and mean value of stent diameter) and calculate the stent eccentricity index. During PCI, stent eccentricity index, post-stent expansion, poorly positioned stent with open lesions, failure of overlapping stent with long lesions, mean cumulative dose (CD), product of total dose area (DAP), X-ray time, operation time and operation cost of each PCI were recorded in the two groups. Patients were followed up for 18 months after PCI, and the occurrence of adverse cardiovascular events (MACE) was recorded during the follow-up period, and the cumulative survival rate without MACE was compared between the two groups. Results:There were no statistically significant differences between the two groups in stent eccentricity index, proportion of guided stent expansion, proportion of poorly positioned stent with open lesions, proportion of stent failure to overlap, with statistically significant difference[(0.12±0.04) vs (0.10±0.03); 80.49% vs 85.49%; 2.44% vs 2.54%; 1.22% vs 2.54%, all P>0.05]. There were no significant differences in CD, X-ray time and DAP in SBS group compared with IVUS group [(1 394.18±42.29)Gy/cm 2 vs (1 391.82±45.06)Gy/cm 2; (18.79±3.01)min vs (18.95±3.12)min, (100.24±5.70)Gy/cm 2 vs (99.47±5.93)Gy/cm 2; all P>0.05]. The operation time in SBS group was shorter than that in IVUS group [(70.91±6.51)min vs (73.89±8.95)min, P<0.05], and the operation cost was less than that in IVUS group [(2.98±0.86)ten thousand yuan vs (3.85±0.81)ten thousand yuan, P<0.05]. After 18 months of follow-up after PCI, Kaplan-Meier survival analysis showed that there was no significant difference in MACE event-free survival between SBS group and IVUS group (91.46% vs 94.07%, Log Rank=0.480, P=0.489). Conclusions:SBS is a kind of convenient and effective technique in guiding PCI in patients with complex coronary lesions without increasing operation time and radiation dose, which can achieve the same effect as IVUS guidance.

OBJECTIVE：To study the composition and contents of flavonoids chemical components in waste material during industrialization of Pueraria thomsonii resources，and to provide reference for comprehensive development and reasonable utilization of the variety. METHODS ：Using“No. 2 Gange”of P. thomsonii from Jiangxi as objects ，UPLC-Q-TOF-MS and HPLC method were adopted to detect the components and contents of flavonoids in the root （with or without cortex ），cortex，flower， fibrous root ，stem，head and dregs （with or without cortex ）of P. thomsonii as well as dry matter of industrial wastewater （with or without cortex ）after precipitation of pueraria powder. RESULTS ：The linearity ，precision，repeatability，stability and recovery of the established method for content determination of 7 flavonoids（puerarin，daidzin，iridoxine-7-O-xylose glucoside ，genistin， iridin，daidzein and kakkalide ）were all in line with the requirements. Totally 12 kinds of flavonoids were identified ，among which the flavonoids in the root ，cortex，stem，fibrous root ，head and dregs of P. thomsonii as well as dry matter of industrial wastewater were the same ，mainly were puerarin ，daidzin，genistein，daidzein and malonyl-daidzein. The flower of P. thomsonii mainly included iridoxine- 7-O-xylose glucoside ，genistin，iridin，kakkalide，6″-O-xylosyldaidzein，but the components as puerarin ， daidzin and its aglycone were not be detected. The content of puerarin in the head of P. thomsonii was the highest （5.765％）. The contents of puerarin in root and dregs of P. thomsonii as well as dry matter of industrial waste-water in samples with cortex were all higher than in corresponding peeled sample. CONCLUSIONS ：The waste material from the industrialization of P. thomsonii resources contains a lot of flavonoids with rich species and high content ，and can be used as an important raw material for obtaining flavonoids such as puerarin.