Four main flavonoids of the Chinese medicine Rhododendri Daurici Folium were studied using the density functional theory (DFT) B3LYP method with 6-311 + + G (d, p) basis set．Their activities were analyzed based on molecular structure, bond dissociation energy (BDE) and the energy gap between HOMO and LUMO. As a result, the antioxidant ability order of the four flavonoids compounds is farrerol

AIM: To observe the hemostatic effect and hemostasis mechanism of XHJ (Auena fatua L.) oral Liqnid on animals. METHODS: Bleeding time (BT) and clotting time (CT) were measured by means of tail cutting and glass slide method on mice, Von willebrand factoe (vWF), prothrombin time (PT) and Kaolin partial thromboplastin time (KPTT) were observed by immunoterbidimerry and coagulase test, antithrombin Ⅲ(AT-Ⅲ) by chromophoric matrix method platelet count by tissue plasminogen activator (tPA), plasminogen activatore inactivator (PAI). CONCLUSION: The results indicate that XHJ has remarkable effect on hemostasis; Its mechanism is related to accelerating blood coagulatlon, inhibiting fibrinolytic activity, adding blood vessel endothelial cell release and improving platelet adhesiveness and aggregation.

ObjectiveTo discover and analyze single or several correlative key amino acid sites that influence the host tropism during the influenza A virus （IAV） infection based on complete internal protein gene segments of IAV strains， and to provide evidence for the study of human host-adaptive mutations of IAV. MethodsThe full-length nucleotide sequences of 43 671 IAV strains containing 6 complete internal gene segments were downloaded from the GISAID EpiFlu^TM database， and 698 human-tropic （HU） and 1 266 avian-tropic （AV） representative strains were included. The consensus coding sequences of the representative strains from the amphitropic category were compared by R script， and the differential amino acid sites and their polymorphisms were then obtained. The multi-site combination analysis of differential sites was conducted with R script. ResultsA total of 49 and 57 conserved differential sites were obtained from the consensus sequence comparison between AV and H1N1 （subtype from HU）， and comparison between AV and H3N2 （another subtype from HU）， separately. 79 and 65 multi-site combinations were found between HU and AV strains through 3 and 4 sites combination analysis， respectively， and a total of 11 conserved sites were involved： site 271 and 684 in PB2； site 336， 486， 581 and 621 in PB1； site 204 and 356 in PA； site 33， 305 and 357 in NP. No eligible differential sites were found in M1 and NS1. ConclusionSeveral conserved amino acid differential sites， between HU and AV strains of IAV， are found in PB2， PB1， PA and NP proteins. Instead of working as single units， these sites may have interactions， forming specific amino acid combinations that determine the host tropism of IAV collectively.

Targeted point mutagenesis through homologous recombination has been widely used in genetic studies and holds considerable promise for repairing disease-causing mutations in patients. However, problems such as mosaicism and low mutagenesis efficiency continue to pose challenges to clinical application of such approaches. Recently, a base editor (BE) system built on cytidine (C) deaminase and CRISPR/Cas9 technology was developed as an alternative method for targeted point mutagenesis in plant, yeast, and human cells. Base editors convert C in the deamination window to thymidine (T) efficiently, however, it remains unclear whether targeted base editing in mouse embryos is feasible. In this report, we generated a modified high-fidelity version of base editor 2 (HF2-BE2), and investigated its base editing efficacy in mouse embryos. We found that HF2-BE2 could convert C to T efficiently, with up to 100% biallelic mutation efficiency in mouse embryos. Unlike BE3, HF2-BE2 could convert C to T on both the target and non-target strand, expanding the editing scope of base editors. Surprisingly, we found HF2-BE2 could also deaminate C that was proximal to the gRNA-binding region. Taken together, our work demonstrates the feasibility of generating point mutations in mouse by base editing, and underscores the need to carefully optimize base editing systems in order to eliminate proximal-site deamination.
APOBEC-1 Deaminase ; genetics ; metabolism ; Animals ; Bacterial Proteins ; genetics ; metabolism ; Base Sequence ; CRISPR-Associated Protein 9 ; CRISPR-Cas Systems ; Cytidine ; genetics ; metabolism ; Embryo Transfer ; Embryo, Mammalian ; Endonucleases ; genetics ; metabolism ; Gene Editing ; methods ; HEK293 Cells ; High-Throughput Nucleotide Sequencing ; Humans ; Mice ; Mice, Inbred C57BL ; Microinjections ; Plasmids ; chemistry ; metabolism ; Point Mutation ; RNA, Guide ; genetics ; metabolism ; Thymidine ; genetics ; metabolism ; Zygote ; growth & development ; metabolism ; transplantation