Clinical evaluation of a rapid colloidal gold immunochromatography assay for SARS-Cov-2 IgM/IgG.

BACKGROUND: Since December 2019, there had been an outbreak of COVID-19 in Wuhan, China. At present, diagnosis COVID-19 were based on real-time RT-PCR, which have to be performed in biosafe laboratory and is unsatisfactory for suspect case screening. Therefore, there is an urgent need for rapid diagnostic test for COVID-19. OBJECTIVE: To evaluate the diagnostic performance and clinical utility of the colloidal gold immunochromatography assay for SARS-Cov-2 specific IgM/IgG anti-body detection in suspected COVID-19 cases. METHODS: In the prospective cohort, 150 patients with fever or respiratory symptoms were enrolled in Taizhou Public Health Medical Center, Taizhou Hospital, Zhejiang province, China, between January 20 to February 2, 2020. All patients were tested by the colloidal gold immunochromatography assay for COVID-19. At least two samples of each patient were collected for RT-PCR assay analysis, and the PCR results were performed as the reference standard of diagnosis. Meanwhile 26 heathy blood donor were recruited. The sensitivity and specificity of the immunochromatography assay test were evaluated. Subgroup analysis were performed with respect to age, sex, period from symptom onset and clinical severity. RESULTS: The immunochromatography assay test had 69 positive result in the 97 PCR-positive cases, achieving sensitivity 71.1% [95% CI 0.609-0.797], and had 2 positive result in the 53 PCR-negative cases, achieving specificity 96.2% [95% CI 0.859-0.993]. In 26 healthy donor blood samples, the immunochromatography assay had 0 positive result. In subgroup analysis, the sensitivity was significantly higher in patients with symptoms more than 14 days 95.2% [95% CI 0.741-0.998] and patients with severe clinical condition 86.0% [95% CI 0.640-0.970]. CONCLUSIONS: The colloidal gold immunochromatography assay for SARS-Cov-2 specific IgM/IgG anti-body had 71.1% sensitivity and 96.2% specificity in this population, showing the potential for a useful rapid diagnosis test for COVID-19. Further investigations should be done to evaluate this assay in variety of clinical settings and populations.

Engineering diverse eubacteria promoters for robust Gene expression in Streptomyces lividans.

Due to the lack of powerful gene regulation elements, the engineering development of Streptomyces is often limited. Here, we disclosed that the heterologous σ70 -dependent promoters, which have been reported as inefficient tools for gene expression in Streptomyces, could be efficiently recognized by Streptomyces housekeeping factor σhrdB. Therefore, an effective strategy was developed to engineer these promoters for robust gene expression in Streptomyces by fusing them with optimized 5'-untranslation regions (5'-UTRs). As a proof of concept, the widely used Ptac in E. coli was engineered by fusing its core promoter region with the 5'-UTRR15 from a relatively powerful Streptomyces promoter PkasO*R15 and resulted in Ptac*, the activity of which was 8.1-fold that of Ptac and 1.7-fold that of PkasO*R15 in S. lividans TK24. Next, the 5'-UTRR15 was optimized by randomizing the ribosome binding site (RBS). Based on the base biases of those RBSs with higher activity, eight artificial RBSs were rationally designed, and the optimal resulting promoter Ptac*RBS3 showed about 2.1, 3.6, and 17.6 times the activity of Ptac*, PkasO*R15, and Ptac, respectively, demonstrating that the heterologous Ptac was converted into a type of robust Streptomyces promoters. This study thus greatly expands promoter diversity for the engineering of Streptomyces.

C²Maps: a network pharmacology database with comprehensive disease-gene-drug connectivity relationships.

BACKGROUND: Network pharmacology has emerged as a new topic of study in recent years. It aims to study the myriad relationships among proteins, drugs, and disease phenotypes. The concept of molecular connectivity maps has been proposed to establish comprehensive knowledge links between molecules of interest in a given biological context. Molecular connectivity maps between drugs and genes/proteins in specific disease contexts can be particularly valuable, since the functional approach with these maps helps researchers gain global perspectives on both the therapeutic profiles and toxicological profiles of candidate drugs. METHODS: To assess drug pharmacological effect, we assume that "ideal" drugs for a patient can treat or prevent the disease by modulating gene expression profiles of this patient to the similar level with those in healthy people. Starting from this hypothesis, we build comprehensive disease-gene-drug connectivity relationships with drug-protein directionality (inhibit/activate) information based on a computational connectivity maps (C²Maps) platform. An interactive interface for directionality annotation of drug-protein pairs with literature evidences from PubMed has been added to the new version of C²Maps. We also upload the curated directionality information of drug-protein pairs specific for three complex diseases - breast cancer, colorectal cancer and Alzheimer disease. RESULTS: For relevant drug-protein pairs with directionality information, we use breast cancer as a case study to demonstrate the functionality of disease-specific searching. Based on the results obtained from searching, we perform pharmacological effect evaluation for two important breast cancer drugs on treating patients diagnosed with different breast cancer subtypes. The evaluation is performed on a well-studied breast cancer gene expression microarray dataset to portray how useful the updated C²Maps is in assessing drug efficacy and toxicity information. CONCLUSIONS: The C²Maps platform is an online bioinformatics resource that provides biologists with directional relationships between drugs and genes/proteins in specific disease contexts based on network mining, literature mining, and drug effect annotating. A new insight to assess overall drug efficacy and toxicity can be provided by using the C²Maps platform to identify disease relevant proteins and drugs. The case study on breast cancer correlates very well with the existing pharmacology of the two breast cancer drugs and highlights the significance of C²Maps database.

Chinese narcotics trafficking: a preliminary report.

Questions of existence of the "China Route" for drug smuggling and trafficking have been important in the literature. The profile of the offenders, particularly whether they are primarily members of traditional criminal organization, is a hotly debated issue. Much qualitative evidence has been collected and it provides important insights into these questions. However, little quantitative data has ever been collected and analyzed to provide a broader picture of these issues. The present study involves the systematical collection of data from court sentencing files from seven high courts whose jurisdictions cover the China Route. The findings provide valuable information that sheds light on the debated questions. Some evidence consistent with the China Route arguments is found. No evidence supports the idea that traditional organized criminal syndicates are behind most offenses. Logistic regression results reveal interesting associations between offender characteristics and types of offenses.

Simultaneous determination of betulin and betulinic acid in white birch bark using RP-HPLC.

A simple procedure is described for the simultaneous extraction and determination of betulin and betulinic acid in white birch bark. The extraction was checked using different solvents: dichloromethane, ethyl acetate, acetone, chloroform, methanol and 95% ethanol (aqueous solution, v/v). It was found 95% ethanol was a good extraction solvent that allowed extraction of triterpenoid with a highest content. Separation was achieved on a reversed phase C(18) column with acetonitrile-water 86:14 (v/v). Detection was accomplished with UV detection at lambda=210 nm. Using this method, the bioactive triterpenoid in white birch bark were simultaneously determined. Significant variations in the content of betulin and betulinic acid in white birch bark growing in different locations of China were also observed.