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.

Liver transplantation (LT) has become a standard treatment for end-stage liver diseases, and graft injury is intricately associated with poor prognosis. Granzyme B (GZMB) plays a vital role in natural killer (NK) cell biology, but whether NK-derived GZMB affects graft injury remains elusive. Through the analysis of single-cell RNA-sequencing data obtained from human LT grafts and the isolation of lymphocytes from mouse livers following ischemia-reperfusion injury (IRI), we demonstrated that 2NK cells with high expression of GZMB are enriched in patients and mice. Both systemically and liver-targeted depletion of NK cells led to a notable reduction in GZMB⁺ cell infiltration, subsequently resulting in diminished graft injury. Notably, the reconstitution of Il2rg ^-/- Rag2 ^-/- mice with purified Gzmb-KO NK cells demonstrated superior outcomes compared to those with wild-type NK cells. Crucially, global knockout of GZMB and pharmacological inhibition exhibited remarkable improvements in liver function in both mouse IRI and rat LT models. Moreover, a phosphorylated derivative of FDA-approved vidarabine was identified as an effective inhibitor of mouse GZMB activity by molecular dynamics, which could provide a potential avenue for therapeutic intervention. Therefore, targeting NK cell-derived GZMB during the LT process suggests potential therapeutic strategies to improve post-transplant outcomes.

The amino acid sequences of the OmpA protein isolated from Escherichia coli QML2206-1(E.coli QML2206-1)in our laboratory were analyzed for homology with different strains of OmpA proteins using bioinformatics software,and the OmpA protein was analyzed for its physicochemical properties,transmembrane structure and signal peptide prediction,B-cell anti-genic epitope prediction,secondary and tertiary structure prediction.The OmpA gene fragment was ligated with pET-32a vector to construct a prokaryotic expression vector,which was purified by a nickel column affinity purification system after prokaryotic expression and optimization of ex-pression conditions in BL21(DE3).The purified recombinant protein was fully mixed with Freund's adjuvant to immunize mice,and the levels of mouse-specific IgG antibody and the expression levels of cytokines CD4,CD8 and IL-4 in mouse serum were detected by ELISA,and the immuno-protective effect was evaluated by mouse attack protection test.OmpA protein is a hydrophilic protein with no transmembrane structural domains and a secondary structure consisting mainly of irregular coils(47.98％)and α-helices(29.77％),with 12 antigenic epitopes that can bind to anti-bodies produced by B cells.The recombinant protein OmpA with a relative molecular mass of a-bout 55 kDa was successfully obtained by prokaryotic expression,and the highest expression was induced by IPTG concentration of 0.000 4 mmol/L for 6 h at 37 ℃.The serum-specific IgG anti-body potency of recombinant protein immunized mice was up to 1∶32 000;the expression levels of CD4,CD8 and IL-4 in the serum of immunized mice were elevated compared with those of the con-trol group.The survival rate of mice was 80％and 40％after attack with minimum lethal dose(MLD)and 2 times minimum lethal dose(2MLD),respectively.OmpA recombinant protein has good antigenicity and certain immunoprotective effects,and this study provides a technical basis for the next step in the development of a genetically engineered subunit vaccine against yak-appli-cable E.coli based on OmpA protein.

Objective:To explore the assessment value of 3.0T magnetic resonance(MR)diffusion weighted imaging(DWI)-apparent diffusion coefficient(ADC)on disease severity in elderly patients with acute pancreatitis(AP).Methods:A total of 68 elderly AP patients who admitted to Weihai Hospital of Traditional Chinese Medicine from August 2023 to September 2024 were retrospectively selected,and they were enrolled in cases group,and 40 healthy persons were included in healthy control group.According to the disease severity,the cases group were divided further into mild-moderate group(n=35)and severe group(n=33).The ADC value and fast diffusion ADC(Ft ADC)fraction of all groups were compared,and receiver operating characteristic(ROC)curve was adopted to evaluate the predictive value of ADC value on the disease severity of AP patients.Results:There were significant differences in ADC values and Ft ADC values among healthy control group,mild-moderate group and severe group(F=30.821,23.145,P＜0.05).The orders of ADC values were as follows from high to low:severe group(0.92±0.24)＞mild-moderate group(0.86±0.23)＞control group(0.58±0.12).The orders of Ft ADC values were as follows from high to low:healthy control group(0.59±0.18)＞mild-moderate group(0.45±0.15)＞severe group(0.35±0.11).The accuracy,sensitivity and specificity of ADC value combined with Ft ADC value were respectively 93.33%,96.23%and 90.38%in diagnosing disease severity.The accuracy and sensitivity of the combined examination were respectively higher than 82.86%and 75.47%of single ADC value,and were respectively higher than 85.71%and 84.91%of single Ft ADC value.Conclusion:With the increasing of disease severity of acute pancreatitis,ADC value gradually decreased,while Ft ADC value gradually increased.The diagnostic efficiency of the combination of ADC value and Ft ADC value for the disease severity were significantly higher than that of single indicator.Therefore,the combined application of ADC value and Ft ADC can help to improve the assessment accuracy for the disease severity of elderly AP patients,which can provide important basis for clinical treatment and disease management.

Objective: To explore the relative importance of different food attributes and levels in food decision making of school aged children, and to understand their meal preferences, so as to provide the evidence for formulating precise intervention strategies for dietary behaviours of school aged children. Methods: From May to June 2024, a total of 854 children aged 11 to 15 years old were selected from 2 middle schools (each school in urban and rural areas) in both Hubei Province and Anhui Province by stratified cluster random sampling method to conduct a D-optimal discrete choice experiment. The mixed Logit model was used to analyze children s preference for meal attributes and different levels, and to calculate the relative importance (RI) of attributes and willingness to pay (WTP) in meal choices. Results: The included five food attributes had statistical significance on meal choice of school aged children ( P <0.05). The relative importance of food attributes affecting the meal choices of school aged children in descending order were dining mode ( RI =31.26%), food varieties ( RI =30.56%), cooking method( RI =23.84%), taste( RI =8.06%) and price ( RI =6.27%). Among them, school aged children preferred home cooked meals ( β =0.74) (WTP=86.3 yuan),varied foods(grain/tubers+vegetables+fish, meat, eggs and beans) ( β =0.61) (WTP=71.9 yuan), fried/roasted cooking ( β =0.51) and spicy taste ( β =0.33).Price was negatively correlated with meal choices( β =-0.01) ( P <0.05). Based on residential area and body mass index (BMI), the stratified analysis showed that dining mode was highest in the relative importance for rural children with overweight and obese children ( RI =31.28%,34.17%), both of whom preferred home cooked meals ( β =0.76, 0.91), and meals containing fish, meat, eggs and beans with grain/tubers or grain/tubers and vegetables in terms of food choice (area: β =0.53, 0.53 ; BMI: β =0.55, 0.56) ( P <0.05). Conclusions School aged children have different preferences for different attributes of meals. The quality of school meals should be improved,the cost of buying healthy meals should be reduced,targeted family health education should be carried out,and healthy cooking methods should be advocated.

Objective To explore the application of serum signal transducer and activator of transcription 3(STAT3),histone deacetylase 2(HDAC2),and developmental endothelial locus-1(Del-1)levels in the evaluation of disease severity and prognosis of children with respiratory syncytial virus pneumonia(RSVP).Methods A total of 109 children with RSVP admitted to Jiamusi Central Hospital from November 2023 to March 2025 were enrolled as the RSVP group.Based on disease severity,RSVP patients were categorized into a low-risk group(n=31),a medium-risk group(n=42),and a high-risk group(n=36).According to the prognosis after 7 days of treatment,they were divided into a favorable prognosis group(n=78)and a poor prognosis group(n=31).Additionally,109 healthy children undergoing physical examination at the same hospital during the same period were selected as the normal control group(NC group).ELISA method was used to detect serum levels of STAT3,HDAC2,and Del-1.Pearson correlation analysis was used to explore the correlations between serum STAT3,HDAC2,Del-1 levels and pulmonary function indices.Multivariate logistic regression analysis was used to explore the factors affecting the prognosis of children with RSVP.Moreover,ROC curve was used to explore the predictive value of serum STAT3,HDAC2,and Del-1 levels for the prognosis of children with RSV.Results Compared with the NC group,the RSVP group had higher serum STAT3 and HDAC2 levels,and lower serum Del-1 levels(P<0.05).Serum STAT3 and HDAC2 levels progressively increased from the low-risk group,medium risk group,to high-risk group,while the time to peak ratio(time to peak tidal expiratory flow to total expiratory time ratio,TPTEF/TE),peak volume ratio(volume to peak expiratory flow to total expired volume ratio,VPEF/VE),and serum Del-1 levels progressively decreased(P<0.05).TPTEF/TE and VPEF/VE were prominently negatively correlated with serum STAT3 and HDAC2 levels,and prominently positively correlated with Del-1 levels(P<0.05).Compared with the favorable prognosis group,the poor prognosis group had significantly lower initial blood oxygen saturation,serum Del-1 levels,and significantly higher serum STAT3 and HDAC2 levels(P<0.05).High expression levels of STAT3 and HDAC2 were independent risk factors affecting the prognosis of children with RSVP,while high expression of Del-1 was an independent protective factor(P<0.05).The AUC values of serum STAT3,HDAC2,and Del-1 levels alone in predicting the prognosis of children with RSV were 0.824,0.818,and 0.842,respectively.The combined prediction AUC was 0.947,which was superior to individual predictions(ZSTAT3-joint=2.436,ZHDAC2-joint=2.570,ZDel-1-joint=2.611,all P<0.05).Conclusion Serum expression of STAT3 and HDAC2 is upregulated,while the expression of Del-1 is down-regulated in children with RSVP.The three markers are closely related to the disease severity and pulmonary function indices,and are important factors affecting the prognosis of children with RSVP.Combined detection of these markers demonstrates high efficacy for prognosis evaluation.

Objective:To investigate the expression of N6-methyladenosine(m6A)reader heterogeneous nuclear ribonucleoprotein A2/B1(hnRNPA2B1)in human gastric cancer(GC)tissue and its effect on the proliferation and invasion of MKN-28 cells.Methods:The Cancer Genome Atlas and Gene Expression Omnibus were used to analyze the expression of hnRNPA2B1 and long noncoding RNA(ln-cRNA)mir-100-let-7a-2-mir-125b-1 cluster host gene(MIR100HG)in GC tissue and their association with the clinical prognosis of patients with GC.Quantitative PCR and Western blotting were used to measure the effect of hnRNPA2B1 on the expression level of MIR100HG and its downstream Wnt/β-catenin signaling pathway;Methylated RNA immunoprecipitation(MeRIP)was used to mea-sure the m6A level of MIR100HG;CCK-8 assay and Transwell assay were used to observe cell proliferation and invasion.Results:Com-pared with paracancerous tissue,human GC tissue showed significant increases in the expression levels of hnRNPA2B1(t=6.101,P<0.001)and MIR100HG(t=2.191,P=0.036 7),and the high expression levels of hnRNPA2B1 and MIR100HG were associated with poor survival in patients with GC.Knockdown of hnRNPA2B1 reduced the mRNA expression level(t=5.156,P=0.007)and m6A level of MIR100HG(t=4.789,P=0.010),inhibited the proliferation and invasion of MKN-28 cells(t=4.915,P=0.008 and t=5.167,P=0.007),and blocked the activity of the Wnt/β-catenin signaling pathway(P<0.05).Overexpression of MIR100HG promoted cell pro-liferation and invasion(t=3.578,P=0.023 and t=8.411,P=0.001),activated the Wnt/β-catenin signaling pathway(P<0.01),and re-versed the antitumor effect induced by hnRNPA2B1 knockdown(t=3.667,P=0.021).Conclusion:This study shows that hnRNPA2B1-mediated m6A modification of MIR100HG promotes the proliferation and invasion of GC MKN-28 cells by activating the Wnt/β-catenin signaling pathway.

Atopic dermatitis (AD) is a prevalent inflammatory skin disorder in which patients experience recurrent eczematous lesions and intense itching. The colonization of Staphylococcus aureus (S. aureus) is correlated with the severity of the disease, but its role in AD development remains elusive. Using single-cell RNA sequencing, we uncovered that keratinocytes activate a distinct immune response characterized by induction of Il24 when exposed to methicillin-resistant S. aureus (MRSA). Further experiments using animal models showed that the administration of recombinant IL-24 protein worsened AD-like pathology. Genetic ablation of Il24 or the receptor Il20rb in keratinocytes alleviated allergic inflammation and atopic march. Mechanistically, IL-24 acted through its heterodimeric receptors on keratinocytes and augmented the production of IL-33, which in turn aggravated type 2 immunity and AD-like skin conditions. Overall, these findings establish IL-24 as a critical factor for onset and progression of AD and a compelling therapeutic target.
Dermatitis, Atopic/genetics* ; Interleukins/metabolism* ; Animals ; Methicillin-Resistant Staphylococcus aureus/immunology* ; Mice ; Keratinocytes/microbiology* ; Humans ; Interleukin-33/immunology* ; Inflammation/microbiology* ; Staphylococcal Infections/microbiology* ; Disease Models, Animal ; Hypersensitivity/microbiology* ; Mice, Inbred C57BL

The amino acid sequences of the OmpA protein isolated from Escherichia coli QML2206-1(E.coli QML2206-1)in our laboratory were analyzed for homology with different strains of OmpA proteins using bioinformatics software,and the OmpA protein was analyzed for its physicochemical properties,transmembrane structure and signal peptide prediction,B-cell anti-genic epitope prediction,secondary and tertiary structure prediction.The OmpA gene fragment was ligated with pET-32a vector to construct a prokaryotic expression vector,which was purified by a nickel column affinity purification system after prokaryotic expression and optimization of ex-pression conditions in BL21(DE3).The purified recombinant protein was fully mixed with Freund's adjuvant to immunize mice,and the levels of mouse-specific IgG antibody and the expression levels of cytokines CD4,CD8 and IL-4 in mouse serum were detected by ELISA,and the immuno-protective effect was evaluated by mouse attack protection test.OmpA protein is a hydrophilic protein with no transmembrane structural domains and a secondary structure consisting mainly of irregular coils(47.98％)and α-helices(29.77％),with 12 antigenic epitopes that can bind to anti-bodies produced by B cells.The recombinant protein OmpA with a relative molecular mass of a-bout 55 kDa was successfully obtained by prokaryotic expression,and the highest expression was induced by IPTG concentration of 0.000 4 mmol/L for 6 h at 37 ℃.The serum-specific IgG anti-body potency of recombinant protein immunized mice was up to 1∶32 000;the expression levels of CD4,CD8 and IL-4 in the serum of immunized mice were elevated compared with those of the con-trol group.The survival rate of mice was 80％and 40％after attack with minimum lethal dose(MLD)and 2 times minimum lethal dose(2MLD),respectively.OmpA recombinant protein has good antigenicity and certain immunoprotective effects,and this study provides a technical basis for the next step in the development of a genetically engineered subunit vaccine against yak-appli-cable E.coli based on OmpA protein.

Objective To analyze the molecular epidemiology and colistin-resistant genes of carbapenem-resistant Klebsiella pneumoniae(CRKP)by whole-genome sequencing,and to provide reference for clinical diagnosis and treatment.Methods 57 CRKP strains isolated from clinical specimens of hospitalized patients in a tertiary general first-class hospital in Anhui Province from 2021 to 2023 were collected and antimicrobial susceptibility testing was performed.Multilocus sequence typing,capsule serotype,resistance genes,and virulence genes of CRKP strains were analyzed by whole-genome sequencing technique,and single nucleotide polymorphism analysis was conducted on sequences of all strains.Colistin resistance-related genes were amplified by polymerase chain reaction(PCR).Results 57 CRKP strains exhibited resistance to 14 antimicrobial agents,with the exception of tigecycline.The se-quencing results showed that 93.0％(53/57)of CRKP carried blaKPC-2,and the ST11 type CRKP strain had the highest detection rate(51/57,89.5％).Single nucleotide polymorphism clustering analysis showed that the 57 CRKP strains were divided into 11 clone groups,of which 4 clone groups were all ST11-KL64 type CRKP.40(70.2％)CRKP strains carried multiple virulence genes.Five strains of CRKP were colistin-resistant strains,the resistance mechanism involved the insertion of ISKpn26 element at site 70 of the mgrB gene.Conclusion The CRKP strain is primarily characterized by the production of KPC-2 ST11-KL64,with disseminated transmission in intensive care unit.The insertion of ISKpn26 element leading to mgrB gene mutation is related to resistance of CRKP to colistin in this region.