ABSTRACT
One of the structural uniqueness of arylnaphthalene lignans (ANLs) is their potential atropoisomerism, which may result in bioactivity discrepancy. However, the stable ANL atropisomers rarely exist in nature. In the course of our phytochemical study of Justicia procumbens, we isolated nine ANL glycosides (1-9) with four of them (1-4) being identified as new stable atropisomers. Their absolute configurations were determined based on the analysis of the circular dichroism (CD) and electronic circular dichroism (ECD) data. The ANL compounds were evaluated for their antiviral potential as entry inhibitors against the infections of H5N1 influenza virus, vesicular stomatitis virus (VSV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with 5 being the most potent one with IC50 values ranging from 0.0063-1.13 mu M. The atropisomers did not display significant antiviral activity, indicating that a free rotation of the biphenyl aryl-aryl bond could play a significant role in the antiviral activity of ANL compounds.
ABSTRACT
Objective This study is conducted against a case of positive nucleic acid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) of environmental samples in a medical institution in Chengdu. Epidemiological investigation methods and laboratory tests are used to investigate the source and analyze the cause of the case, to explore the nucleic acid monitoring mode and the disposal scheme of abnormal conditions of SARS-CoV-2 in the medical institution environment. Methods Chengdu and Shuangliu district CDC jointly investigate A Medical Institution (A refers to a specific anonymous medical institute). Epidemiological surveys were conducted though related influencing factors of the medical institution. SARS-CoV-2 nucleic acid detection kits were used for detection. Sequencing was carried out on a second-generation sequencing platform. Results From Jan.18th 2021 to Jan.20th 2021, a total of 62 smear samples of environment and articles were collected, among which 30 samples were positive for SARS-CoV-2 nucleic acid. 30 positive samples were divided into Gongwei building (9) and Zhonghe building (21) according to the sampling location. The samples' Ct values of ORF1ab gene in Gongwei building were lower than that in Zhonghe building, and the difference was statistically significant (t=2.452, P=0.036). According to the nature of the specimens, they were divided into external environment smear samples (24 samples) and cleaning tool smear samples (6 samples). The N gene Ct values of external environment smear samples were lower than that of cleaning tools, and the difference was statistically significant (Z=-2.204, P=0.028). Through gene sequencing analysis, the sequence of SARS-CoV-2 nucleic acid positive environmental samples detected this time is highly homologous with SARS-CoV-2 vaccine (> 99.9%). Conclusions The positive environmental samples of SARS-CoV-2 nucleic acid in the medical institution are caused by the damage and leakage of COVID-19 vaccine ampoules in the process of vaccination, which led to the contamination of the vaccination room of public health building, and then transmit to the hospital environment of fever clinic and complex building through cleaning tools by cleaning workers. With the progress of COVID-19 vaccine vaccination, there is a high probability of environmental pollution of vaccine liquid in the vaccination area of medical institutions. Therefore, it is necessary in combination with the current normalization monitoring requirements of domestic COVID-19 epidemic situation to refine the specific implementation plan, conduct vaccination in a scientific and orderly manner, and reduce the social impact. © 2022, Publication Centre of Anhui Medical University. All rights reserved.
ABSTRACT
An epidemiological investigation was carried out on a local cluster of outbreak caused by imported cases of Coronavirus Disease 2019 (COVID-19) in rural areas of Chengdu in December 2020, to find out the source of infection and the chain of transmission. According to Prevention and Control Protocol for COVID-19 (Version 7), field epidemiological investigation was adopted, combined with big data technology, video image investigation, gene sequencing and other methods to carry out investigation into COVID-19 cases and infections source tracing, analyze the epidemiological association, and map the chain of transmission. From December 7 to 17, 2020, 13 local COVID-19 confirmed cases and 1 asymptomatic case were diagnosed in Chengdu, of which 12 cases (85.71%) had a history of residence and activity in the village courtyard of Taiping (TP), Pidu (P) District, Chengdu. From November 8, 2020 to November 28, 2020, a group of inbound people form Nepal were transferred to the designated entry personnel quarantine hotel of P District which was adjacent to the TP village. During quarantine, there were 5 cases who tested positive for COVID-19. Through gene sequencing alignment, genes of local cases and Nepalese imported cases from the same period are homologous, all belong to the lineage of L2.2.3 (B.1.36 according to Pangolin lineage typing method). According to the results of field epidemiological investigation and gene sequencing analysis, the index case was most likely infected by contact with household waste of quarantine site. Under the situation of normalization prevention and control of COVID-19, sentinel monitoring of fever clinics in primary medical institutions is the key to early detection of the epidemic. The multi-department joint epidemiological investigation and the application of gene technology are the core links of the investigation and traceability of modern infectious diseases. The allocation of public health resources in rural areas needs to be strengthened. We need to improve the capacity for early surveillance and early warning of the epidemic in rural areas.
Subject(s)
COVID-19 , Epidemics , Disease Outbreaks , Humans , Quarantine , SARS-CoV-2ABSTRACT
Coronavirus, identified as a zoonotic pathogen, can cause pulmonary infections and even a pandemic. Corona Virus Disease 2019 (COVID-19), which was induced by a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), struck the world in December 2019. There is no specific drug for coronavirus. As a classical antimalarial drug, chloroquine has been proved to have antiviral activity by changing the pH of endocytosis, via autophagy reactions and by changing the glycosylation mode of the virus envelope. At the cellular level, chloroquine has inhibitory effects on SARS-CoV, Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV-2. Recent clinical research results are beginning to show that chloroquine can improve the success rate and prognosis. Chloroquine has been used less clinically in recent years due to the many adverse reactions it causes. The safety of chloroquine used in coronavirus infection requires in-depth evaluation. This article summarizes research progress in the anti-coronavirus effect and safety of chloroquine in order to provide reference for its clinical application. © 2020 Chinese Journal of Pharmacology and Toxicology. All rights reserved.