[Epidemiology, Treatment, and Epidemic Prevention and Control of the Coronavirus Disease 2019: a Review].

This review summarizes the ongoing researches regarding etiology, epidemiology, transmission dynamics, treatment, and prevention and control strategies of the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with comparison to severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and pandemic H1N1 virus. SARS-CoV-2 may be originated from bats, and the patients and asymptomatic carriers are the source of epidemic infection. The virus can be transmitted human-to-human through droplets and close contact, and people at all ages are susceptible to this virus. The main clinical symptoms of the patients are fever and cough, accompanied with leukocytopenia and lymphocytopenia. Effective drugs have been not yet available thus far. In terms of the prevention and control strategies, vaccine development as the primary prevention should be accelerated. Regarding the secondary prevention, ongoing efforts of the infected patients and close contacts quarantine, mask wearing promotion, regular disinfection in public places should be continued. Meanwhile, rapid detection kit for serological monitoring of the virus in general population is expected so as to achieve early detection, early diagnosis, early isolation and early treatment. In addition, public health education on this disease and prevention should be enhanced so as to mitigate panic and mobilize the public to jointly combat the epidemic.

[Prokaryotic Expression of Rv0757 Gene in Mycobacterium tuberculosis and the Effect of Its Coding Protein on the Function of Macrophage].

OBJECTIVE: To construct recombinant plasmid pET28a-Rv0757 with Mycobacterium tuberculosis (Mtb) Rv0757 gene, and to determine the effect of the protein of Rv0757 gene on ANA-1 cells. METHODS: We recombined the amplified Rv0757 gene into theprokaryotic plasmid pET28a (+). The expressed product was identified by SDS-PAGE and Western blot. Murine macrophages were treated with purified protein PhoP. Survived cells, lactic dehydrogenase (LDH), nitric oxide (NO), and cell apoptosis were detected after the treatment. RESULTS: We successfully constructed the recombinant plasmid pET28a-Rv0757. The target protein was confirmed by SDS-PAGE and Western blot. The protein had no significant effect on cell numbers and LDH activities in the culture supernatant, but it inhibited the release of NO and apoptosis of ANA-1 cells. CONCLUSION: pET28a-Rv0757 plasmid with prokaryotic expression was successfully constructed. The targetprotein has no toxicity on macrophages, but it can inhibit NO release and cell apoptosis of ANA-1.