Objective This study aimed to assess the efficiency and purification of the Trace DNA extraction with a quantified method for the magnetic bead-based DNA extraction as performed on the Tecan Automated systems with TE-MAGS magnetic separator. Methods Serial dilutions of standard commercial DNA 9947A were used with the total DNA contents, 0.1ng, 0.2ng,0.3ng, 0.4ng,0.5ng, 0.6ng, 0.7ng, 0.8ng, 0.9ng,1ng,diluted progressively and a 1ng DNA (standard commercial DNA 9947A) admixed with 6 common DNA-PCR inhibitors were extracted on the Automated systems and then performed via Fluorogenic probe quantitative PCR and STR genotype for the quantification analysis of recovery and purification. Results The recovery rate of standard 9947A DNA diluted with 0.1~1ng was 38.92~60.01%, and 0.3ng and more DNA could observed the full STR profiles. For the different PCR inhibitors, above 94.5% of bile acid, collagen and urea were efficient removal during the purification process, and the hemoglobin, melanin and humic acid removal efficiency were about 97.5%, 97.85%, 82.14%, respectively.Conclusion Our results suggested that The TE-MAGS magnetic bead-based DNA extraction was suitable for the extraction of trace DNA with high recovery efficiency and purification ability.

AIM:To study the mechanism of Sihei-fang(SHF)in improving pigment deficiency disease(PD)by combining network pharmacology and me-tabolomics.METHODS:Using zebrafish embryos with pigment deficiency disease induced by 1-phe-nyl-2-thiourea(PTU)as an animal model,the ef-fects of SHF extract(0.01,0.02,0.04 mg/mL)on the morphology,melanin area,tyrosinase activity,and melanin content of zebrafish embryos were an-alyzed.Ultra high performance liquid chromatogra-phy-mass spectrometry(UHPLC-MS)was used to screen differential metabolites and obtain relevant metabolic pathways in the SHF treatment of mela-nin deficient zebrafish embryos model.Network pharmacology was used to obtain key targets for SHF treatment of PD and conduct KEGG pathway enrichment analysis.Import The identified differen-tial metabolites and SHF PD intersection targets were imported into the Metscape plugin,to estab-lish a"metabolite reaction enzyme gene"network,and search for key metabolites,targets,and meta-bolic pathways.RESULTS:SHF treatment could in-crease the formation of zebrafish melanin,activate tyrosinase activity,and increase melanin content.Metabolomics analysis obtained 54 differential me-tabolites,and metabolic pathway analysis was con-ducted on these metabolites,involving the biosyn-thesis of phenylalanine,tyrosine,and tryptophan,glycerol phospholipid metabolism,tyrosine metab-olism,linoleic acid metabolism,and aminoacyl tRNA biosynthesis pathways.Network pharmacolo-gy had obtained 55 cross targets of components and diseases.KEGG involved pancreatic cancer,TNF,cancer and other signal pathways.The joint analysis of metabolomics and network pharmacolo-gy identified four key targets:COMT,CYP1B1,TYR,and ALDH2;three key metabolites:L-tyrosine,ho-movanllate,L-lysine;three important metabolic pathways:tyrosine metabolism,valine/leucine/iso-leucine degradation,and lysine metabolism.CON-CLUSION:SHF has a good improvement effect on PD,and combined with metabolomics and network pharmacology,SHF may enhance its influence on the tyrosine metabolism pathway by regulating the metabolite L-tyrosine,thereby promoting the for-mation of melanin.

A new variant of concern for SARS-CoV-2,Omicron(B.1.1.529),was designated by the World Health Organization on November 26,2021.This study analyzed the viral genome sequenc-ing data of 108 samples collected from patients infected with Omicron.First,we found that the enrichment efficiency of viral nucleic acids was reduced due to mutations in the region where the primers anneal to.Second,the Omicron variant possesses an excessive number of mutations compared to other variants circulating at the same time(median:62 vs.45),especially in the Spike gene.Mutations in the Spike gene confer alterations in 32 amino acid residues,more than those observed in other SARS-CoV-2 variants.Moreover,a large number of nonsynonymous mutations occur in the codons for the amino acid residues located on the surface of the Spike protein,which could potentially affect the replication,infectivity,and antigenicity of SARS-CoV-2.Third,there are 53 mutations between the Omicron variant and its closest sequences available in public databases.Many of these mutations were rarely observed in public databases and had a low muta-tion rate.In addition,the linkage disequilibrium between these mutations was low,with a limited number of mutations concurrently observed in the same genome,suggesting that the Omicron vari-ant would be in a different evolutionary branch from the currently prevalent variants.To improve our ability to detect and track the source of new variants rapidly,it is imperative to further strengthen genomic surveillance and data sharing globally in a timely manner.