AIM　The purpose is to study the anti-arrhythmic effects of extracts from cultured Cordyceps sinensis. METHODS　Aconitine and barium chloride were used to induce experimental arrhythmia models in rats. RESULTS　The results showed that PE was more potent than other ingredients. Pretreatment with PE by oral administration significantly antagonized arrhythmia induced by aconitine. PE significantly prolonged the onset of arrhythmia, decreased the duration and diminished the degree of severity. And in barium chloride-induced arrhythmia model, PE had some anti-arrhythmia effect，which could diminish the degree of severity effectively to some extent. CONCLUSION　PE is an active component to antagonize arrhythmia induced by aconitine and barium chloride.

Aim To construct the fusion gene of human IgG3 upper hinge region and p53 tetramerization domain and to analyze its space conformation. Methods The fusion gene was obtained by recursive polymerase chain reaction (R-PCR),and was cloned into vector pUC19. The positive clone was selected and sequenced with PE310 auto-sequencer. The space conformation of the fusion gene expression product was predicted by using computer program Antheprot. Results Restriction endonuclease digestion confirmed that the fusion gene has been inserted correctly into the vector. The result of sequencing showed that the fusion gene is identical with designation. Analyzing with antheprot program showed that the fusion gene expression product could auto-assembly into a tetramer with four long and flexible linkers. Conclusion Successful construction of the fusion gene mentioned above laid the foundation for further preparation of multivalent gene engineering antibody.

Objective:To explore the clinical evaluation outcomes of COVID-19 risk assessment scale on organ donation and procurement during the pandemic of novel coronavirus pneumonia (NCP) and reduce the incidence of donor-derived infection and medical staff infection.Methods:From January 20 to February 29 in 2020, the organ procurement team adopted the COVID-19 risk assessment scale for evaluating 8 potential donors. They were classified into the levels of high/low/uncertain risk by analyzing the risk levels of donation hospitals, clinical characteristics and exposure history. The coordinators, organ evaluators and ward medical staff adopted essential protective measures. The infection status of 2019-nCoV in the above mentioned staff was examined and graft function in the corresponding recipients were observed.Results:Based upon the COVID-19 risk assessment results, the risk level was high (n=8), low (n=5) and uncertain (n=2) and underwent organ procurement. A total of 19 grafts including liver, kidney, pancreas and heart were harvested and successfully utilized for organ transplantation. During the observation period of 14 days, there was no suspected or confirmed infection of 2019-nCoV among coordinators and medical staff. No graft dysfunction or acute rejection was observed during a follow-up period of 4 to 30 days. No recipient was suspected or confirmed to be infected with 2019-nCoV and 6 of them were negative for 2019-nCoV nucleic acid testing after organ transplantation.Conclusions:During the COVID-19 pandemic, it is safe to proceed with donor organ evaluations and procurements according to the result with the COVID-19 risk assessment scale. Low-risk donor organ donation may be carried out, uncertain risk donor organ donation should be performed cautiously and high-risk donations discouraged.