Quality standardization of complementary medicine is fundamental for industry and practice as it underpins the quality,safety and efficacy of Chinese herbal medicines.Current herbal standardizations are often based on the quantitative analysis of a single compound,which may not reflect the total characteristic,bioactive and toxic nature of the herbs or products.Therefore,there is a need to establish an internationally recognized methodology for quality standardization of Chinese herbal medicines.The analytical methods reviewed in this article are pharmacognosy,TLC,HPLC,LCMS,CE and chemo-metrics.This article also covers the developments and applications of these methods in quality standardization.Recent advances show that a combination of these methods creates an overall chemical profile of each herb.This iS supported by results reviewed in this article and obtained in our laboratory tests on medicinal herbs including Hypericum perforatum,Morinda officinalis and Centella asiatica.Significant variations in active components have been observed between herbal samples and products.It is proposed that the identification of active components,pharmacological activities and eventual clinical applications are required for a comprehensive quality standardization system.Our findings indicate that the combination of various chromatographic and chemometric methods will advance the methodology of quality standardization and enhance the overall confidence in herbal medicine for the health practitioner and the public.

Humans ; Lemierre Syndrome/drug therapy* ; Anti-Bacterial Agents/therapeutic use*

Objective: To study the infection rate of secondary close contacts of COVID-19 patients, and assess the infection risk in the contacts. Methods: COVID-19 patients' close contacts (with a clear exposure time to index case) with negative nucleic acid test results and secondary close contacts were surveyed in continuous isolation and medical observation in this prospective study. The dynamic nucleic acid test results of the close contacts and secondary contacts of COVID-19 patients were collected to assess their risk of infection. Results: A total of 4 533 close contacts were surveyed, in whom 14 were confirmed as COVID-19 patients with overall secondary attack rate of 0.31%, and 4 201 secondary contacts were tracked, in whom no subsequent infections occurred. Conclusion: Close contacts of COVID-19 patients entered in centralized isolation for medical observation with negative nucleic acid tese results,the secondary close contacts of COVID-19 patients have no risk of infection.
COVID-19/epidemiology* ; Contact Tracing ; Humans ; Incidence ; Nucleic Acids ; Prospective Studies ; SARS-CoV-2