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.

Objective:Patients with metastatic urothelial carcinoma(mUC)usually receive platinum-based chemotherapy as the first-line treatment.Recently,antibody-drug conjugates(ADCs)combined with programmed death-1 antibody(PD-1 antibody)have shown promising efficacy and safety in the treatment of mUC.HER2 positivity is associated with poor prognosis,patients can benefit from anti-HER2 ADC therapy such as disitamab vedotin(RC48-ADC).This study aimed to evaluate the efficacy and safety of RC48-ADC combined with tislelizu-mab in treatment-na?ve patients with mUC.Methods:A retrospective analysis was performed on 70 mUC patients treated between July 2022 and December 2023,including 30 patients receiving RC48-ADC combined with tislelizumab(DT group)and 40 patients receiving gem-citabine plus cisplatin(GC group).Primary endpoints included objective response rate(ORR),disease control rate(DCR),progression-free survival(PFS),overall survival(OS),and treatment-related adverse events(TRAEs).Results:The ORR(73.3%vs.47.5%)and DCR(86.7%vs.62.5%)were significantly higher in the DT group compared to the GC group(P<0.05).The DT group also demonstrated longer PFS(10.98 months vs.7.67 months,P<0.005)and prolonged OS(median OS:not reached vs.11.34 months).The most common TRAEs included myel-osuppression,gastrointestinal and hepatobiliary toxicities,fatigue,alopecia,and rash.No grade≥3 TRAEs or treatment-related deaths were reported.Conclusions:RC48-ADC combined with tislelizumab demonstrated superior efficacy and favorable safety in treatment-na?ve pa-tients with mUC,supporting its potential as a first-line therapeutic option.

Objective To investigate the mechanism by which Senegenin(SEN)alleviates microglial inflammatory response through the nuclear factor erythroid 2-related factor 2(Nrf2)/NOD-like receptor protein 3(NLRP3)pathway.Methods BV2 mouse microglia cells were randomly divided into control group,model group,SEN group and MCC950 group.Cells in control group were not treated,and cells in model group were added with 1 μg/ml lipopolysaccharide(LPS);Cells in SEN group were added with 1 μg/ml LPS+4 μmol/L SEN,and cells in MCC950 group were added with 1 μg/ml LPS+10 μmol/L MCC950 for 24 hours.CCK-8 method was used to detect the effect of different concentrations of SEN on the viability of BV2 cells.Griess method was used to determine the release amount of nitric oxide(NO)in the supernatant.Real-time fluorescent quantitative PCR was used to determine the mRNA expression levels of NLRP3,lymphocyte apoptosis-associated spect-like protein containing a CARD(ASC),caspase-1,interleukin(IL)-1β and IL-18 mRNA.Immunofluorescence staining was used to detect the expression levels of ASC,IL-1β,Nrf2 and heme oxygenase-1(HO-1).Western blotting was used to detect the expression levels of NLRP3,caspase-1,ASC,IL-1β,IL-18,Nrf2,HO-1,nuclear factor kappa B(NF-κB)and inducible nitric oxide synthase(iNOS).Results The results of CCK-8 method showed that there was no significant difference in the viability of BV2 cells treated with 2～20 μmol/L SEN compared with control group(P>0.05).Compared with control group,the viability of BV2 cells in model group decreased significantly(P<0.05).Compared with model group,the viability of BV2 cells in 4 μmol/L SEN group was significantly restored(P<0.05).Compared with control group,the results of Griess method showed that the release amount of NO in cells of model group increased significantly(P<0.05);the results of real-time PCR showed that the expression levels of NLRP3,ASC,caspase-1,IL-1β and IL-18 mRNA in cells of model group increased significantly(P<0.05);the results of Western blotting showed that the protein expression levels of NLRP3,ASC,caspase-1,IL-1β and IL-18 proteins in cells of model group increased significantly(P<0.05),and the immunofluorescence staining results showed that the expression levels of iNOS and NF-κB protein in cells of model group increased,and the expression levels of Nrf2 and HO-1 decreased,with statistically significant differences(P<0.05).Compared with model group,the release amount of NO in cells of SEN group and MCC950 group decreased,and the expression levels of NLRP3,ASC,caspase-1,IL-1β and IL-18 mRNA and proteins decreased,with statistically significant differences(P<0.05);in the SEN group,the expression levels of iNOS and NF-κB decreased,and immunofluorescence staining showed that Nrf2 was translocated into the nucleus,and the expression levels of Nrf2 and HO-1 proteins increased significantly,with statistically significant differences(P<0.05).Conclusions SEN could alleviate the inflammatory response of mouse microglia cells induced by LPS and inhibit the activation and expression of NLRP3 inflammasome,with an effect comparable to that of the inflammasome inhibitor MCC950.The mechanism may be related to the regulation of the expression of upstream factors Nrf2 and HO-1.

Although teniposide(VM26)is widely used in the treatment of lymphoma,its poor water sol-ubility,low bioavailability and systemic toxicities still limit its clinical application.Nano-delivery systems are effective in increasing the bioavailability and reducing the toxicity of VM26,but there is an urgent need to overcome the problem of its non-specific targeting.Therefore,in this paper,we designed and constructed a hyaluronic acid-modified teniposide-targeted nano-delivery system(VM26-TNDS),and characterised its drug encapsulation rate,particle size and zeta potential.We also investigated the effects of VM26-TNDS on B-cell lymphoma cells with different expression of CD44 receptor,in terms of cellular targeting,inhibitory effect of proliferation,and induction of apoptosis and necrosis.The results showed that the drug encapsulation efficiency of VM26-TNDS exceeded 85％,and its liquid formulation could be stably stored at 4 ℃ for more than 6 months without precipitation.Based on CD44 receptor expression,Granta-519(high expression),Raji(medium-low expression)and SU-DHL-4(almost no expression)were screened for cellular experiments.Compared with VM26-NDS,the targeted modification could effec-tively reduce the uptake of VM26-TNDS by RAW264.7 and increase the uptake of VM26-TNDS by CD44 receptor-expressing lymphoma cells.The inhibitory proliferative effect and apoptotic necrosis-inducing a-bility of VM26-TNDS were stronger than those of VM26-NDS for Granta-519 and Raji cells,whereas there was no significant difference in the inhibitory effect on proliferation and ability to induce apoptosis and necrosis between VM26-NDS and VM26-TNDS in SU-DHL-4 cells,reflecting the targeting advantage for VM26-TNDS,as expected.However,its toxic effect on B-cell lymphoma cells only reflected the targeting advantage at some concentrations(0.25 μmol/L and 0.5 μmol/L),which met the expectation.The a-bove results indicate that a teniposide-targeted nano-delivery system,VM26-TNDS,has been successfully prepared in this study.VM26-TNDS improves the delivery efficiency of VM26 by targeting human B-cell lymphoma cells expressing the CD44 receptor,thus killing human B-cell lymphoma cells more effectively and overcoming the problem of non-specific targeting in drug delivery to improve the therapeutic effect.Its biological therapeutic effects and mechanisms still need to be proved by more in vitro and in vivo ex-perimental evidence.

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.

In recent years,the potential role of mitochondrial dynamics imbalance in the pathogenesis of various psychiatric disorders has attracted growing attention.Mitochondria regulate energy metabolism,oxidative stress,apoptosis,and neuronal function through dynamic processes such as fission and fusion.Disruption of these processes may impair synaptic function and neural network stability.In schizophrenia,depression,bipolar disorder,Alzheimer disease,and autism spectrum disorders,studies have reported dysregulated expression of mitochondrial fission-related proteins DRP1 and FIS1,as well as fusion-related proteins MFN1,MFN2,and OPA1,accompanied by structural and functional mitochondrial impairments,neuronal apoptosis,and synaptic loss.Evidence from clinical studies,animal models,and cell experiments further supports that these mitochondrial dynamics abnormalities are closely associated with cognitive deficits,emotional disturbances,and neurodegenerative changes.Although mitochondrial dynamic dysfunction alone cannot fully explain the onset of psychiatric disorders,it may represent a potential biological mechanism that offers new insights into disease mechanisms and provide a theoretical basis for developing targeted intervention strategies.

In recent years,the potential role of mitochondrial dynamics imbalance in the pathogenesis of various psychiatric disorders has attracted growing attention.Mitochondria regulate energy metabolism,oxidative stress,apoptosis,and neuronal function through dynamic processes such as fission and fusion.Disruption of these processes may impair synaptic function and neural network stability.In schizophrenia,depression,bipolar disorder,Alzheimer disease,and autism spectrum disorders,studies have reported dysregulated expression of mitochondrial fission-related proteins DRP1 and FIS1,as well as fusion-related proteins MFN1,MFN2,and OPA1,accompanied by structural and functional mitochondrial impairments,neuronal apoptosis,and synaptic loss.Evidence from clinical studies,animal models,and cell experiments further supports that these mitochondrial dynamics abnormalities are closely associated with cognitive deficits,emotional disturbances,and neurodegenerative changes.Although mitochondrial dynamic dysfunction alone cannot fully explain the onset of psychiatric disorders,it may represent a potential biological mechanism that offers new insights into disease mechanisms and provide a theoretical basis for developing targeted intervention strategies.

Although teniposide(VM26)is widely used in the treatment of lymphoma,its poor water sol-ubility,low bioavailability and systemic toxicities still limit its clinical application.Nano-delivery systems are effective in increasing the bioavailability and reducing the toxicity of VM26,but there is an urgent need to overcome the problem of its non-specific targeting.Therefore,in this paper,we designed and constructed a hyaluronic acid-modified teniposide-targeted nano-delivery system(VM26-TNDS),and characterised its drug encapsulation rate,particle size and zeta potential.We also investigated the effects of VM26-TNDS on B-cell lymphoma cells with different expression of CD44 receptor,in terms of cellular targeting,inhibitory effect of proliferation,and induction of apoptosis and necrosis.The results showed that the drug encapsulation efficiency of VM26-TNDS exceeded 85％,and its liquid formulation could be stably stored at 4 ℃ for more than 6 months without precipitation.Based on CD44 receptor expression,Granta-519(high expression),Raji(medium-low expression)and SU-DHL-4(almost no expression)were screened for cellular experiments.Compared with VM26-NDS,the targeted modification could effec-tively reduce the uptake of VM26-TNDS by RAW264.7 and increase the uptake of VM26-TNDS by CD44 receptor-expressing lymphoma cells.The inhibitory proliferative effect and apoptotic necrosis-inducing a-bility of VM26-TNDS were stronger than those of VM26-NDS for Granta-519 and Raji cells,whereas there was no significant difference in the inhibitory effect on proliferation and ability to induce apoptosis and necrosis between VM26-NDS and VM26-TNDS in SU-DHL-4 cells,reflecting the targeting advantage for VM26-TNDS,as expected.However,its toxic effect on B-cell lymphoma cells only reflected the targeting advantage at some concentrations(0.25 μmol/L and 0.5 μmol/L),which met the expectation.The a-bove results indicate that a teniposide-targeted nano-delivery system,VM26-TNDS,has been successfully prepared in this study.VM26-TNDS improves the delivery efficiency of VM26 by targeting human B-cell lymphoma cells expressing the CD44 receptor,thus killing human B-cell lymphoma cells more effectively and overcoming the problem of non-specific targeting in drug delivery to improve the therapeutic effect.Its biological therapeutic effects and mechanisms still need to be proved by more in vitro and in vivo ex-perimental evidence.

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.

Objective:Patients with metastatic urothelial carcinoma(mUC)usually receive platinum-based chemotherapy as the first-line treatment.Recently,antibody-drug conjugates(ADCs)combined with programmed death-1 antibody(PD-1 antibody)have shown promising efficacy and safety in the treatment of mUC.HER2 positivity is associated with poor prognosis,patients can benefit from anti-HER2 ADC therapy such as disitamab vedotin(RC48-ADC).This study aimed to evaluate the efficacy and safety of RC48-ADC combined with tislelizu-mab in treatment-na?ve patients with mUC.Methods:A retrospective analysis was performed on 70 mUC patients treated between July 2022 and December 2023,including 30 patients receiving RC48-ADC combined with tislelizumab(DT group)and 40 patients receiving gem-citabine plus cisplatin(GC group).Primary endpoints included objective response rate(ORR),disease control rate(DCR),progression-free survival(PFS),overall survival(OS),and treatment-related adverse events(TRAEs).Results:The ORR(73.3%vs.47.5%)and DCR(86.7%vs.62.5%)were significantly higher in the DT group compared to the GC group(P<0.05).The DT group also demonstrated longer PFS(10.98 months vs.7.67 months,P<0.005)and prolonged OS(median OS:not reached vs.11.34 months).The most common TRAEs included myel-osuppression,gastrointestinal and hepatobiliary toxicities,fatigue,alopecia,and rash.No grade≥3 TRAEs or treatment-related deaths were reported.Conclusions:RC48-ADC combined with tislelizumab demonstrated superior efficacy and favorable safety in treatment-na?ve pa-tients with mUC,supporting its potential as a first-line therapeutic option.