Research progress on antiviral effect of active components of traditional Chinese medicine and their mechanisms

In recent years, with the frequent occurrence of viral diseases accompanied by high morbidity and mortality rates, there has been an increasing awareness of importance of antiviral drugs research. Traditional Chinese medicine contain biologically structurally diverse bioactive substances that provide important template structures for pharmaceutical research. Because of its novelty, multicomponent and multi-target characteristics, it is a valuable source for new drug development. The antiviral mechanisms of active components of traditional Chinese medicines include inhibition of viral replication, block binding of virus with receptor, directly killing virus, enhancement of the immune system and inhibition of cytokines/chemokines responses, etc. The active components of traditional Chinese medicine with antiviral active ingredients based on the mechanism of antiviral action were reviewed in this paper, in order to provide a basis for development of antiviral natural drugs to cope with the virus epidemic including the new variant of SARS-CoV-2 and other virus outbreaks that may occur in the future. © 2022 Editorial Office of Chinese Traditional and Herbal Drugs. All rights reserved.

An empirical-likelihood-based structural-change test for INAR processes

The empirical likelihood ratio (ELR) test is proposed for uncovering a structural change in integer-valued autoregressive (INAR) processes. The limiting distribution is derived under the null hypothesis that the parameter did not change at the anticipated change points. To evaluate the finite-sample performance of the proposed ELR test, the empirical sizes and powers are investigated in a simulation study. The ELR test is also applied to real data on infectious disease and crime counts.

The Security of Blockchain-Based Medical Systems: Research Challenges and Opportunities

The current COVID-19 pandemic has, perhaps, expedited the move to electronic medical systems (e.g., telemedicine). However, in the digitalization of healthcare services, we have to ensure the security and privacy of (sensitive) healthcare data, often stored locally in the hospital's server or remotely within a trusted cloud server. There have been many attempts to design blockchain-based approaches to support security and privacy in medical systems, and this is the focus of this article where we systematically review the existing literature on blockchain-based medical systems. We then categorize the existing security solutions into three categories, namely, 1) decentralized authentication, 2) access control, and 3) audit, and discuss the privacy protection technologies in blockchain-based healthcare systems. Based on our analysis, we identify a number of challenges, including performance limitations and inflexible audit, as well as future research opportunities (e.g., the need for lightweight security schemes for blockchain-based medical systems).

Research progress on therapeutic drugs for corona virus disease 2019

Corona virus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. At present, there is no specific antiviral drug for this virus, and the main clinical treatment is support and symptomatic treatment. Direct targeting the virus and the host targets are two strategies for the development of antiviral drugs. At present, the research and development of COVID-19 therapeutic drugs has made some progress on both approaches. Here we review potential anti-SARS-CoV-2 drugs to discuss the antiviral mechanisms and potential of these drugs from the perspectives of virus and host. The role of traditional Chinese medicine in the treatment of COVID-19 is discussed along with the prospects for drug treatment strategies of COVID-19.

[Genomic analysis of a 2019-novel coronavirus (2019-nCoV) strain in the first COVID-19 patient found in Hangzhou].

Objective: To understand the viral genomic characteristics of a 2019-novel coronavirus (2019-nCoV) strain in the first COVID-19 patient found in Hangzhou, China. Methods: Viral RNA was extracted in throat swab and sputum sample of the patient and was performed real-time reverse transcription PCR detection and obtained viral genome by high-throughput sequencing method. Phylogenetic analysis was conducted using 29 2019-nCoV genomes and 30 ß-coronavirus genomes deposited in NCBI GenBank. Fifteen genomes from Wuhan were grouped by mutation sites and others were identified by Wuhan's or specific mutation sites. Results: A 29 833 bp length genome of the first 2019-nCoV strain in Hangzhou was obtained, covering full length of the coding regions of coronavirus. Phylogenetic analysis showed that the genome was closest to the genome of a bat SARS-like coronavirus strain RaTG13 with an identity of 96.11% (28 666/29 826). Among the genes between two genomes, E genes were highly conserved (99.56%), while S genes had lowest identity (92.87%). The genome sequence similarities among 29 strains from China (Hangzhou, Wuhan, and Shenzhen), Japan, USA, and Finland, were all more than 99.9%; however, some single nucleotide polymorphisms were identified in some strains. Conclusion: The genome of Hangzhou 2019-nCoV strain was very close to the genomes of strains from other cities in China and overseas collected at early epidemic phase. The 2019-nCoV genome sequencing method used in this paper provides an useful tool for monitoring variation of viral genes.

[Comparison of epidemiological and clinical characteristics of SARS, pandemic (H1N1) 2009 and COVID-19, and consideration of the prevention and control strategies on COVID-19].

In this paper, the epidemiological and clinical characteristics of severe acute respiratory syndrome (SARS), pandemic (H1N1) 2009 and COVID-19 were compared. Compared with the other two diseases, COVID-19 is more contagious, more concealed in transmission, greater infectious intensity and more severe in clinical manifestations. If the COVID-19 epidemic was not effectively controlled, it would have a serious impact on human health and even social development. Understanding the characteristics of three diseases, especially COVID-19, and improving the awareness of the harmfulness of COVID-19 are of certain significance to the implementation of the guiding principle of "scientific prevention and treatment, precise implementation of strategies" and the prevention and control of COVID-19.