The continuous emergence of SARS-CoV-2 variants as well as other potential future coronavirus has challenged the effectiveness of current COVID-19 vaccines. Therefore, there remains a need for alternative antivirals that target processes less susceptible to mutations, such as the formation of six-helix bundle (6-HB) during the viral fusion step of host cell entry. In this study, a novel high-throughput screening (HTS) assay employing a yeast-two-hybrid (Y2H) system was established to identify inhibitors of HR1/HR2 interaction. The compound IMB-9C, which achieved single-digit micromolar inhibition of SARS-CoV-2 and its Omicron variants with low cytotoxicity, was selected. IMB-9C effectively blocks the HR1/HR2 interaction in vitro and inhibits SARS-CoV-2-S-mediated cell-cell fusion. It binds to both HR1 and HR2 through non-covalent interaction and influences the secondary structure of HR1/HR2 complex. In addition, virtual docking and site-mutagenesis results suggest that amino acid residues A930, I931, K933, T941, and L945 are critical for IMB-9C binding to HR1. Collectively, in this study, we have developed a novel screening method for HR1/HR2 interaction inhibitors and identified IMB-9C as a potential antiviral small molecule against COVID-19 and its variants.

Qualitative and quantitative analysis methods for chemical components of different processed products of Corni Fructus were established to systematically characterize and identify these components, and the content of the main differential components was determined. The chemical components of different processed products of Corni Fructus were collected using ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS). Through analysis of self-built databases, literature, and reference standards, a total of 93 components were obtained, including 19 iridoids, 15 flavonoids, 16 organic acids, eight triterpenoids, eight tannins, four amino acids, two polysaccharides, five olefins, and 16 other compounds. Additionally, by using multivariate statistical methods, the differential components between different processed products of Corni Fructus were screened under the conditions of VIP>1.0 and FC<0.5 or FC>2.0 and P<0.05. The PCA and OPLS-DA results showed differences in the chemical components between different processed products of Corni Fructus. A total of 21 differential components were screened, including tartaric acid, morroniside, and rutin. On this basis, ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry(UPLC-QqQ-MS/MS) was used to determine the content of 10 main common differential components, including gallic acid, morroniside, ursolic acid, loganin, swertiamarin, rutin, 5-hydroxymethylfurfural, cornuside Ⅰ, quercetin, and oleanolic acid. The above 10 components showed a good linear relationship within the determined concentration range, with the precision, stability, repeatability, and sample recovery rate all meeting the requirements. Compared with that in Corni Fructus, the content of iridoid glycosides in wine-prepared Corni Fructus and wine-and honey-prepared Corni Fructus decreased, while the content of gallic acid, rutin, quercetin, 5-hydroxymethylfurfural, ursolic acid, and oleanolic acid increased. Compared with wine-prepared Corni Fructus, wine-and honey-prepared Corni Fructus showed varying degrees of increase in all other components, except for a slight decrease in gallic acid content. In summary, this study clarified the influence of different processing methods on the chemical components of Corni Fructus, providing a theoretical basis for the scientific connotation, overall quality evaluation, and clinically rational application of Corni Fructus processing in the future.
Tandem Mass Spectrometry/methods* ; Chromatography, High Pressure Liquid/methods* ; Cornus/chemistry* ; Drugs, Chinese Herbal/chemistry* ; Fruit/chemistry*

Poly(lactic-co-glycolide)(PLGA)is a key excipient in long-acting sustained-release preparations,and its degradation properties directly affect the drug release behavior.In this study,PLGA microspheres were prepared by microfluidic techniques,and the morphology changes of the microspheres were observed by scanning electron microscopy(SEM).In alkaline environment,due to the accelerated hydrolysis of ester bonds,the surface of the microspheres was rapidly dissolved and eroded,and the degradation rate was significantly higher than that in acidic environment.High temperature accelerated the degradation of PLGA microspheres.Under neutral and alkaline conditions,the microspheres showed aggregation and adhesion.Under acidic conditions,the microspheres gradually decomposed into irregular fragments.The high ionic strength further promoted the surface corrosion of the microspheres,especially under extreme pH conditions.Simultaneously,PLGA microspheres encapsulating coumarin were prepared to simulate the microsphere formulation.The release rate of coumarin after degradation of the microspheres under different conditions was observed by measuring the absorbance with ultraviolet-visible spectrophotometry.The results were consistent with those of the blank microspheres.This study revealed that the degradation of PLGA microspheres was significantly pH-dependent,temperature sensitive and ion strength responsive.These findings not only helped to understand and optimize the long-term stability and controlled release performance of drug-carrying microspheres,but also provided a theoretical basis for further improvement of PLGA-based drug carrier design.

Objective To explore the relationship between dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)and clinical pathological features of invasive breast cancer and lymphovascular invasion(LVI).Methods Imaging and clinical pathological data were retrospectively collected from 508 patients with invasive breast cancer who underwent breast DCE-MRI at the First Medical Center of Chinese PLA General Hospital from January 2019 to August 2021.Patients were divided into the LVI-positive(LVI+)group(n=79)and LVI-negative(LVI-)group(n=429)based on postoperative pathological results.Univariate and multivariate logistic regression analyses were used to identify risk factors for LVI.Results Compared with LVI-group,LVI+group had a higher proportion of patients aged<45 years(44.3%vs.27.0%,P=0.002),non-mass-like enhancement(NME)(31.7%vs.17.7%,P=0.004),Ki-67 expression rate(40.0%vs.30.0%,P<0.001),high Ki-67 expression(94.9%vs.78.1%,P=0.001),Luminal B subtype(76.0%vs.60.1%,P=0.008),and positive axillary lymph nodes rate(72.2%vs.31.5%,P<0.001),while the proportion of Luminal A subtype was lower(2.5%vs.21.5%,P<0.001).Univariate and multivariate logistic regression analyses showed that age≥45 years(OR=0.468,95%CI 0.280-0.783,P=0.004)was an independent protective factor for LVI,while NME(OR=1.987,95%CI 1.126-3.444,P=0.016)was an independent risk factor.Compared with Luminal A subtype,patients with Luminal B subtype(OR=10.482,95%CI 3.164-64.923,P=0.001),HER-2 overexpression subtype(OR=11.571,95%CI 2.755-79.341,P=0.003)and triple-negative subtypes(OR=8.433,95%CI 1.985-57.908,P=0.009)had a higher risk of LVI.Conclusions Age≥45 years is an independent protective factor for LVI,while NME is an independent risk factor.Among molecular subtypes,patients with Luminal B,HER-2 overexpression and triple-negative subtypes have a higher risk of LVI compared with the Luminal A subtype.

The aim of this study was to understand the internal genetic diversity and population history dynamics of ticks in Inner Mongolia,to provide data for designing effective vector control programs and revealing ticks'transmission mechanisms.From 2022 to 2023,the manual collection method was used to collect samples in Inner Mongolia.The 16S rDNA and COI gene sequences of ticks were used to identify Hyalomma marginatum,Haemaphysalis concinna,and Argas persicus,and analyze the sequence characteristics and genetic diversity within the populations.Base composition analysis indicated that the average A+T content of the 16S rDNA gene and CO I gene in the three ticks was significantly higher than that of C+G.Moreover,22 haplotypes of the COI gene and 12 haplotypes of the 16S rDNA sequence were identified in Hyalomma marginatum.Eleven haplotypes were identified according to the COI gene,and nine haplotypes were identified according to the16S rDNA sequence of Haemaphysalis concinna.Two haplotypes were identified on the basis of the COI gene,and six haplotypes were identified on the basis of the 16S rDNA sequence of Ar gas persicus.The minimum 16S rDNA haplotype diversity was 0.264 for Ar gas persicus and 0.579 for the other two species.The nucleotide diversity of the three tick species was less than 0.05.Tajima's val-ue and Fu's Fs value of the neutrality test were negative.Base saturation substitution analysis indicated that neither of the two genes in the three tick species reached saturation.The phylogenetic tree revealed that Hyalomma marginatum,Haema physalis concinna,and Ar gas persicus in Inner Mongolia independently aggregated into branches.In conclusion,the base content of Hyalomma marginatum,Haemaphysalis concinna,and Argas persicus genes in Inner Mongolia was consist-ent with the characteristics of insect mitochondrial DNA content.Furthermore,the three tick populations showed rapid evolu-tionary population expansion,and the phylogeny of three tick species showed independent aggregation into clades,with no pop-ulation isolation.

The"capitation payment with retained surplus and shared accountability for reasonable overruns"mechanism constitutes a pivotal institutional framework for advancing the high-quality development of County Medical Communities(CMCs).This study addresses two critical operational challenges:identifying the sources of medical insurance fund surplus and optimizing the governance of fund retention processes.Grounded in transaction cost theory,we develop an analytical framework examining the formation of medical insurance fund surplus through the dual lenses of intra-organizational dynamics within CMCs and external medical insurance payment mechanism design.Utilizing Deqing County,Zhejiang Province as an empirical case,this research proposes a five-pronged strategy:Clarifying generation channels of insurance fund surplus,scientifically determining regional medical insurance budgets,implementing bundled payment mechanisms for CMCs,adopting hybrid payment models integrating unified and differentiated approaches,and establishing performance-based incentive systems.These findings elucidate the formative pathways of medical insurance fund surplus while offering theoretical and practical insights for enhancing payment system reforms to support CMC development.

The aim of this study was to understand the internal genetic diversity and population history dynamics of ticks in Inner Mongolia,to provide data for designing effective vector control programs and revealing ticks'transmission mechanisms.From 2022 to 2023,the manual collection method was used to collect samples in Inner Mongolia.The 16S rDNA and COI gene sequences of ticks were used to identify Hyalomma marginatum,Haemaphysalis concinna,and Argas persicus,and analyze the sequence characteristics and genetic diversity within the populations.Base composition analysis indicated that the average A+T content of the 16S rDNA gene and CO I gene in the three ticks was significantly higher than that of C+G.Moreover,22 haplotypes of the COI gene and 12 haplotypes of the 16S rDNA sequence were identified in Hyalomma marginatum.Eleven haplotypes were identified according to the COI gene,and nine haplotypes were identified according to the16S rDNA sequence of Haemaphysalis concinna.Two haplotypes were identified on the basis of the COI gene,and six haplotypes were identified on the basis of the 16S rDNA sequence of Ar gas persicus.The minimum 16S rDNA haplotype diversity was 0.264 for Ar gas persicus and 0.579 for the other two species.The nucleotide diversity of the three tick species was less than 0.05.Tajima's val-ue and Fu's Fs value of the neutrality test were negative.Base saturation substitution analysis indicated that neither of the two genes in the three tick species reached saturation.The phylogenetic tree revealed that Hyalomma marginatum,Haema physalis concinna,and Ar gas persicus in Inner Mongolia independently aggregated into branches.In conclusion,the base content of Hyalomma marginatum,Haemaphysalis concinna,and Argas persicus genes in Inner Mongolia was consist-ent with the characteristics of insect mitochondrial DNA content.Furthermore,the three tick populations showed rapid evolu-tionary population expansion,and the phylogeny of three tick species showed independent aggregation into clades,with no pop-ulation isolation.

The"capitation payment with retained surplus and shared accountability for reasonable overruns"mechanism constitutes a pivotal institutional framework for advancing the high-quality development of County Medical Communities(CMCs).This study addresses two critical operational challenges:identifying the sources of medical insurance fund surplus and optimizing the governance of fund retention processes.Grounded in transaction cost theory,we develop an analytical framework examining the formation of medical insurance fund surplus through the dual lenses of intra-organizational dynamics within CMCs and external medical insurance payment mechanism design.Utilizing Deqing County,Zhejiang Province as an empirical case,this research proposes a five-pronged strategy:Clarifying generation channels of insurance fund surplus,scientifically determining regional medical insurance budgets,implementing bundled payment mechanisms for CMCs,adopting hybrid payment models integrating unified and differentiated approaches,and establishing performance-based incentive systems.These findings elucidate the formative pathways of medical insurance fund surplus while offering theoretical and practical insights for enhancing payment system reforms to support CMC development.

The aim of this study was to clarify the genetic diversity and population history of Ixodes persulcatus in some ar-eas of Inner Mongolia in order to provide accurate data for effective vector control programs and reveal the transmission mecha-nism.Samples were collected in 10 areas of Inner Mongolia during the active tick season(April 2021-July 2023)using the flag-dragging and manual sampling methods.The 16S rRNA and COI gene were sequenced to clarify genetic diversity of I.per-sulcatus.The positivity rates for the COI gene and 16S rRNA were 90.00％and 98.33％respectively.Overall,18 and 15 haplotypes were identified for the COI gene and 16S rRNA,respectively,with a total haplotype diversity＞0.762 and total nucleotide diversity＜0.005.The Tajima's values and Fu's Fs were negative for significance.A nucleotide mismatch map was shown as a single peak.The genetic differentiation index FST of the population indicates a small degree of genetic differ-entiation of the population,while analysis of molecular vari-ance indicates that the variation within populations was greater than between populations.Phylogenetic tree and haplotype network plots showed confounding distributions between hap-lotypes.I.persulcatus from the Hinggan League and Hulun-buir regions can adapt to environmental changes and possess abundant genetic diversity.Genetic differentiation is mainly concentrated within the population and no geographical isolation was observed.