ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

Objective To investigate the effect and mechanism of pomalidomide(POM)on airway inflammation and mucus hypersecretion in rats with chronic obstructive pulmonary disease(COPD).Methods Thirty-six SD rats were randomly divided into control group,model group and POM group,with 12 in each group,half male and half female.The COPD model was established by smoke exposure combined with Klebsiella pneumoniae infection in model group and POM group.The rats in POM group were treated with POM(0.5 mg/kg,once a day for 1 week).The lung function,lung tissue pathology,the proportion of inflammatory cells in bronchoalveolar lavage fluid(BALF)and the levels of serum inflammatory factors tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6 and IL-13 were observed and detected in each group.AB-PAS staining and immunohistochemistry were used to analyze the proliferation of goblet cells and the secretion of mucin(MUC)5AC and MUC5B in airway epithelium of rats.The expression levels of TNF-α receptor 1(TNFR1),IκB kinase(IKK),phosphorylated IKK(p-IKK)and P65 protein in lung tissue were detected by Western blotting.Results Compared with control group,model group showed significant decreased of tidal volume(TV),minute ventilation(MV),forced expiratory vital capacity(FVC),0.1s forced expiratory volume(FEV0.1)and 0.3 s forced expiratory volume(FEV0.3)(P<0.05),increased of the mean linear intercept(MLI)of the alveoli(P<0.01),decreased of the mean alveolar number(MAN)(P<0.01),increased of the proportion of neutrophils and lymphocytes in BALF sediment(P<0.05),and decreased of the proportion of macrophages in BALF sediment(P<0.01);increased of the levels of serum inflammatory factors TNF-α,IL-1β,IL-13 and IL-6(P<0.05),the proportion of goblet cells in airway epithelium(P<0.01),the secretion of MUC5AC and MUC5B in lung tissue(P<0.01),the content of TNFR1 and the ratio of p-IKK/IKK(P<0.01),the content of P65 in nucleus(P<0.01);and decreased of the content of P65 in cytoplasm(P<0.05).Compared with model group,after one week of POM treatment,POM group showed significant improved of the TV,MV,FVC,FEV0.1,FEV0.3,MLI and MAN of rats(P<0.05);decreased of the proportion of neutrophils and lymphocytes in BALF(P<0.05);increased of the proportion of macrophages(P<0.01);decreased of the levels of serum TNF-α,IL-1β,IL-6 and IL-13(P<0.05),the proportion of goblet cells in airway(P<0.01),the secretion of MUC5AC and MUC5B(P<0.01),and the expression of TNFR1,P-IKK and P65(nucleus)(P<0.05);and increased of the level of P65(cytoplasm)(P<0.01).Conclusions POM can improve airway inflammation and mucus hypersecretion in COPD rats,which may be achieved by inhibiting TNF-α/NF-κB signaling pathway.

Through a compound induction method, combined with neurobehavioral, macroscopic characterization and objective pathological evaluation indicators, a murine depression model of liver depression transforming into fire syndrome was constructed and confirmed. The model was constructed using a combination of sleep deprivation, light exposure, and alternate-day food deprivation. Evaluation was conducted at three levels: face validity, constructs validity, and predictive validity. The establishment of the liver depression transforming into fire syndrome depression model was further validated through the counterproof of traditional Chinese medicine formulas. In terms of face validity, compared to the control group, mice in the model group exhibited typical depressive symptoms in neurobehavioral assessments; the general observation of the model group mice reveals disheveled and lackluster fur, along with delayed and easily agitated responses. Additionally, there is a substantial increase in water consumption. In the sleep phase detection of mouse, the model group showed a significant increase in the proportion of time spent in the wake phase during sleep, accompanied by a significant decrease in the proportions of time spent in both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep phases. There are significant differences in physiological indicators such as average blood flow velocity, blood flow rate, tongue, urine, and claw color (r values) in the internal carotid artery. Structural validity demonstrated that levels of 5-hydroxytryptamine (5-HT), dopamine (DA), and γ-aminobutyric acid (GABA) in the hippocampus of model mice decreased significantly, while acetylcholine (ACh), tryptophan (Try), and glutamic acid (Glu) levels increased significantly. Treatment with Danzhi Xiaoyao San led to varying degrees of restoration in the aforementioned neurotransmitters. In terms of predictive validity, the antidepressant paroxetine effectively ameliorated depressive behaviors in the model mice, and the classic formula Danzhi Xiaoyao San demonstrated varying degrees of improvement in depression-related indicators. In conclusion, this study has established a novel animal model of liver-stagnation with the fire depression, thereby expanding the repertoire of traditional Chinese medicine depression models. This development contributes to the diversification of melancholic syndrome models in Chinese medicine, offering a broader spectrum of options for scientific exploration, efficacy evaluation, and drug screening in the future prevention and treatment of depression with traditional Chinese medicine. Animal experiments were conducted with the approval and supervision of the Animal Ethics Committee of Jiangxi University of Traditional Chinese Medicine (ethics number: 20230313040).

AIM:To investigate the effect of circular RNA MYO9A-006(circMYO9A_006)on hypertrophic phenotype of cardiomyocytes and the underlying mechanism.METHODS:The effect of adenovirus-mediated overexpres-sion of circMYO9A_006 on the expression of hypertrophy-related proteins,including β-myosin heavy chain(β-MHC),skeletal muscle actin alpha 1(ACTA1)and atrial natriuretic peptide(ANP),was evaluated in neonatal mouse ventricular cardiomyocytes(NMVCs).Moreover,a neonatal rat ventricular cardiomyocyte(NRVC)model of phenylephrine(PE)-in-duced hypertrophy was established.The effect of circMYO9A_006 overexpression on NRVC size was ascertained using Phalloidin-iFluor 647 staining method.Dual-luciferase reporter assay was employed to measure the activity of potential in-ternal ribosome entry sites(IRES)in circMYO9A_006.The translation and intracellular location of the circMYO9A_006-translated protein,MYO9A-208aa,were verified using Western blot.To investigate the role of MYO9A-208aa in the ef-fect of circMYO9A_006 on the cardiomyocyte hypertrophic phenotype,we prepared and used the following adenoviruses:the recombinant circMYO9A_006-ORF adenovirus to express MYO9A-208aa,the recombinant circMYO9A_006-ATG-mut adenovirus that does not express MYO9A-208aa,the recombinant circMYO9A_006 adenovirus,and the adenovirus vector control.These were then employed to infect NRVCs.RESULTS:Successful adenovirus-mediated overexpression of circMYO9A_006 was observed in NMVCs.The increased expression of circMYO9A_006 notably reduced the expres-sion of hypertrophy-related proteins in NMVCs(P<0.01).Concurrently,overexpression of circMYO9A_006 substantially reduced the expression of hypertrophy-associated proteins and diminished the size of PE-induced NRVCs(P<0.05).Dual-luciferase reporter assay identified the activity of 2 IRES in circMYO9A_006.Western blot results indicated that circ-MYO9A_006 could produce the MYO9A-208aa protein with an anticipated molecular weight of 28 kD in NRVCs,primari-ly found in the cytoplasm.Elevated expression of both circMYO9A_006 and MYO9A-208aa consistently reduced the ex-pression of hypertrophy-associated proteins(P<0.01),and counteracted the enlarged size of PE-induced NRVCs(P<0.05).However,increased expression of circMYO9A_006-ATG-mut did not counteract the PE-induced hypertrophic phe-notype of NRVCs.CONCLUSION:circMYO9A_006 attenuates the hypertrophic phenotype of cardiomyocytes by synthe-sizing the MYO9A-208aa protein.

This study was designed to investigate the effect of silencing microtubule-affinity regulating kinase 4(MARK4)on the apoptosis,inflammatory cytokine release and intestinal barrier protein expression of FHC cells in a lipopolysaccharide(LPS)-induced ulcerative colitis(UC)model,and the underlying molecular mechanisms.Western blot analysis was used to measure the expression levels of MARK4 and apoptosis-related factors including Caspase-1,NLRP3,and GSDMD in colon tissues from both UC patients and healthy individuals,as well as in LPS-induced FHC cell inflammation model.FHC cells was transfected with shRNA to silence MARK4.In control(normal FHC cells),LPS(LPS-stimulated FHC cells),and MARK4-silenced+LPS(shRNA-and LPS-treated FHC cells)groups,the expression levels of Caspase-1,NLRP3,GSDMD,intestinal barrier proteins,and NF-κB pathway-related proteins were assessed by Western blotting.ELISA and RT-qPCR were used to measure the expression levels of inflammatory cytokines IL-1β,IL-6,and TNF-α;flow cytometry was utilized to assess apoptosis.Data showed that both in UC patient colon tissues and the in vitro LPS-induced FHC cell UC inflammation model,there was a significant increase in the expression of MARK4 and apoptosis-related proteins including NLRP3,Caspase-1,and GSDMD.Silencing MARK4 inhibited the expression of these apoptosis-related proteins and downregulated the inflammatory cytokines IL-1β,IL-6,and TNF-α in LPS-induced FHC cells.Silencing MARK4 also reduced apoptosis,increased the expression of intestinal barrier proteins ZO-1,Occludin,and upregulated Claudin2.Gene Set Enrichment Analysis(GSEA)indicated a positive correlation between MARK4 and the NF-κB signaling pathway.Furthermore,silencing of MARK4 inhibited the expression levels of p-P65 and p-IKKα in the NF-κB pathway.In conclusion,MARK4 is significantly upregulated in UC tissues and cells.Silencing MARK4 inhibits the activation of the NF-κB signaling pathway,thereby inhibiting the apoptosis and inflammatory factor expression of UC cells.Thus,MARK4 could be a potential therapeutic target for UC patients.

Objective To observe the therapeutic effect and mechanism of acupuncture at Zusanli-Zhongwan combined matching points on rats with exercise-induced stress gastric ulcer.Methods Forty male SD rats were randomly divided into blank group,model group,acupuncture group and Omeprazole group,with 10 rats in each group.Except for the blank group,the rats in the other groups were used to construct the model of exercise stress gastric ulcer by daily exhaustive swimming.After successful modeling,the acupuncture group was intervened by acupuncture at Zusanli(ST36)and Zhongwan(RN12),once a day,10 minutes each time.Rats in the Omeprazole group were given Omeprazole Enteric-Coated Tablets distilled water suspension by gavage two hours before daily swimming.After continuous 7-day intervention,the overall state and behavior of rats were observed,the gastric mucosal injury index was calculated by Guth method,the pathological morphology of gastric mucosa was observed by hematoxylin-eosin(HE)staining,the contents of superoxide dismutase(SOD),glutathione peroxidase(GSH-PX)and malondialdehyde(MDA)in serum were correspondingly determined by WST-1 method,colorimetry and TBA method,respectively,enzyme-linked immunosorbent assay(ELISA)was used to detect the contents of gastrin(GAS),somatostatin(SS),tumor necrosis factor-α(TNF-α),interleukin-1 β(IL-1β),interleukin-6(IL-6)and interleukin-10(IL-10)in serum,the expression levels of epidermal growth factor receptor(EGFR),matrix metalloproteinase 3(MMP3),nuclear factor erythroid-related factor 2(NRF2),heme oxygenase 1(HO-1)and mitochondrial SOD2,TNF-α,IL-1β,IL-6 and IL-10 mRNA in gastric mucosa were detected by real-time fluorescence quantitative polymerase chain reaction(qPCR).Results Compared with the blank group,the body mass of rats in the model group was increased slowly,the activity distance and activity in the open field test were decreased,the gastric mucosal ulcer index was increased significantly,the gastric mucosal function indexes involving GAS level was increased and SS level was decreased in serum,the mRNA expression level of EGFR in gastric mucosa was decreased and the mRNA expression level of MMP3 in gastric mucosa was increased.The serum levels of antioxidant substances SOD and GSH-PX were decreased significantly,and the serum level of oxidation product MDA was increased significantly.The mRNA expression levels of antioxidant genes NRF2,HO-1 and SOD2 in gastric mucosa were significantly decreased.The serum contents and the gastric mucosa mRNA levels of inflammatory factors TNF-α,IL-1α,IL-6 were significantly increased,while the serum content and the gastric mucosa mRNA level of IL-10 were significantly decreased.The differences were statistically significant(P＜0.05 or P＜0.01 or P＜0.001).HE staining showed obvious gastric mucosal injury.Compared with the model group,the above indexes in the acupuncture group and the Omeprazole group were significantly improved(P＜0.05 or P＜0.01 or P＜0.001).HE staining showed that the gastric mucosal injury was significantly reduced.Conclusion Acupuncture at Zusanli-Zhongwan combined matching points can reduce the local oxidative stress and inflammatory response in rats with exercise-induced stress gastric ulcer,reduce gastric mucosal injury,improve the emotional state of rats,and maintain the overall vitality of rats.

Objective To investigate the improvement effect and mechanism of marmesin on cognitive impairment in Alzheimer's disease(AD)mice.Methods Fifty mice were randomly divided into five groups:blank group,model group,low-and high-dose marmesin groups and donepezil(positive drug)group,with 10 mice in each group.After 21 days of continuous administration,except for the blank group,the mice in other groups were given intraperitoneal injection of scopolamine to establish the AD model.Network pharmacology was used to construct the protein-protein interaction(PPI)network of common targets of marmesin in the treatment of AD,and gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis were performed to provide further research direction.The cognitive function of AD model mice was evaluated by Morris water maze,open field test and new object recognition test.Nissl staining was used to observe the damage of hippocampal neurons.The levels of acetylcholine(Ach),acetylcholine transferase(ChAT),acetylcholinesterase(AChE),reactive oxygen species(ROS),malondialdehyde(MDA)and catalase(CAT)in hippocampus of mice were detected by kit.The protein expression levels of interleukin 6(IL-6),interleukin 1β(IL-1 β),tumor necrosis factor α(TNF-α),nuclear factor E2-related factor 2(NRF2),silent information regulator homologous protein 3(SIRT3),Kelch-like ECH-associated protein 1(KEAP1),quinone oxidoreductase 1(NQO1)and heme oxygenase 1(HO-1)in hippocampus were detected by Western Blot.Results Compared with the model group,the latency of Morris water maze test was significantly shortened in the high-dose marmesin group,the time of entering the target area in the open field new object test and the movement distance in the central area of the open field were prolonged,the number of neurons in the hippocampal CA1 and CA3 regions was significantly increased,the levels of ChAT and Ach in the hippocampus were significantly increased,AChE level was significantly decreased,CAT level was significantly increased,ROS and MDA levels were significantly decreased,TNF-α expression level was decreased,SIRT3 and HO-1 expression levels were increased,and KE AP1 protein expression level was decreased,the differences being statistically significant(P＜0.05 or P＜0.01 or P＜0.001).Conclusion Marmesin can effectively improve the learning and memory impairment of AD mice,and its mechanism may be related to the activation of NRF2/SIRT3 signaling pathway,thereby alleviating oxidative stress level and neuroinflammation,and repairing cholinergic neuron function.

Post-stroke cognitive impairment(PSCI)is a prevalent functional impairments following stroke that seriously affects patients'quality of life and daily activities.Studies indicate a close relationship between intestinal microflora dysbiosis and central nervous system diseases.Intestinal microflora profoundly impacts on human physiological health,contributing to the stability of nervous,metabolic and immune systems through regulation of the gut-brain axis.An increasing number of studies confirmed the important role of the gut microbiome-gut-brain axis in the occurrence and development of stroke and its associated PSCI,and regulation of microbiome-gut-brain could be potential target to treatment of PSCI.This review summarizes research progress on gut microbiome-gut-brain axis and PSCI to provide a reference for exploration of related mechanisms and clinical prevention and treatment strategies.

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]

Mutations in myosin heavy chain 7(MYH7)and myosin binding protein C3(MYBPC3)genes encoding thick filaments are the main cause of hypertrophic cardiomyopathy(HCM),while a small part of HCM is caused by mutations of troponin C1,slow skeletal and cardiac type(TNNC1),troponin T2,cardiac type(TNNT2),troponin I3,cardiac type(TNNI3),actin alpha cardiac muscle 1(ACTC1),and tropomyosin 1(TPM1)genes encoding thin filaments.In this review,we mainly introduce the detailed mechanism and research status of HCM caused by mutations of the gene encoding cardiomyocyte sarcomere in the past few years,in order to provide reference for further study of the pathogenesis and treatment of HCM.