Objective To clone and express the ns5a gene of hepatitis C virus(HCV) 1b strain DY.Methods By using the prokaryotic cell gene engineering,HCV ns5a gene was amplified with nested PCR from the plasmid HCV17 of HCV 1b strain DY full-length gene and inserted into the cloning pMD18-T vector.The cloned HCV ns5a gene was separated and subcloned into expression vector pET-28a and induced by IPTG in E.coli.BL21.The expressed product was identified by SDS-PAGE and Western-blot methods.Results Recombinant expression plasmid pet-28a-ns5a was constructed and expressed successfully.Conclusion HCV ns5a gene was cloned and expressed.This might be helpful for further studies on the nature and biological properties of the ns5a gene.

Objective Emergency response to public health emergencies constitutes a vital component of the modernization of national governance systems and capacities, directly impacting national security, social stability, and public health. This study aims to analyze the key issues and research hotspots in the field of emergency response to public health emergencies, providing theoretical foundations and practical guidance for formulating scientific and effective emergency strategies and policies. Ultimately, it seeks to enhance the nation’s capability to respond to public health emergencies and safeguard public health. Methods Using core journals indexed in the China National Knowledge Infrastructure (CNKI) database as the data source, 1094 journal articles in the field of emergency response to public health emergencies in China from 2003 to September 2024 were selected as the research sample. Citespace visualization software was employed to organize and analyze the research process in the field of emergency response to public health emergencies. Results The current research in this field predominantly involves small-scale cooperation, and the research process can be divided into four stages. The research in the emerging stage mainly focuses on the themes of emergency mechanism and emergency management, the development stage mainly centers on the themes of emergency capacity improvement and system exploration, the outbreak stage emphasizes the themes of COVID-19 and epidemic prevention and control, and the sustainable development stage highlights collaborative governance and informatization. Conclusion The COVID-19 pandemic has accelerated the development of research in this field. Currently, the field shows a continuous growth, with an increasing volume of publications. The focus of current research has shifted towards collaborative governance and the study of assessment tools, aiming to enhance the efficiency and effectiveness in responding to public health emergencies. Moreover, the field is advancing toward more systematic and comprehensive research. However, there is still a need to strengthen scientific communication and collaboration.