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.

BACKGROUND:Ferroptosis is a mode of programmed cell death distinct from apoptosis,necrosis,and other novel cellular deaths,which occurs mainly due to accumulated lipid peroxidation.Ferroptosis has been shown to be involved in the pathological process following subarachnoid hemorrhage.Baicalein,serving as an adept sequestered of iron,evinces its prowess by quelling lipid peroxidative cascades.Nonetheless,the enigma lingers as to whether baicalein possesses the capacity to ameliorate neuronal ferroptosis,elicited in the wake of early brain injury after subarachnoid hemorrhage. OBJECTIVE:To investigate the effect and mechanism of baicalein on neuronal ferroptosis after subarachnoid hemorrhage. METHODS:Primary neuronal cells were extracted from C57BL/6L fetal mice at 16-17 days of gestation.Hemoglobin was used to stimulate primary neuronal cells to simulate an in vitro subarachnoid hemorrhage model.The viability of primary neuronal cells treated with baicalein at concentrations of 5,15,25,50,and 100 μmol/L for 24 hours was detected by CCK-8 assay to determine the optimal concentration of baicalein.Primary neuronal cells were divided into control group,hemoglobin group,and hemoglobin+baicalein group.The levels of reactive oxygen species and malondialdehyde in cells were detected by kits.The mRNA expressions of ferroptosis-related markers PTGS2,SLC7A11,and glutathione peroxidase 4 were detected by RT-PCR.The primary neuronal cells were further divided into control group,SLC7A11 inhibitor Erastin group,hemoglobin group,hemoglobin+baicalein group,and hemoglobin+baicalein+Erastin group.The expression of the ferroptosis related markers SLC7A11 and glutathione peroxidase 4 was detected by western blot assay. RESULTS AND CONCLUSION:(1)Baicalein(25 μmol/L)was selected as the following experimental concentration.(2)Compared with the hemoglobin group,the level of malondialdehyde and the level of reactive oxygen species were significantly decreased(P<0.05)in the hemoglobin+baicalein group.(3)Compared with the hemoglobin group,the mRNA expression of PTGS2 significantly decreased,and the mRNA expression of SLC7A11 and glutathione peroxidase 4 significantly increased(P<0.000 1)in the hemoglobin+baicalein group.(4)SLC7A11 inhibitor Erastin could reverse the baicalin-improved ferroptosis effect to a certain extent(P<0.05).(5)The results showed that baicalein could alleviate the ferroptosis of neuronal cells after subarachnoid hemorrhage through the SLC7A11/GPX4 pathway.

Objective:To study the overall training effect of segmented training model on key fiberoptic bronchoscopy techniques for anesthesiology residents and the influence of key technique training order on the training effect.Methods:Different fiberoptic bronchoscopy simulators were used for specialized training in different key techniques of fiberoptic operation. To examine the effect of key technique learning order on the teaching effect, 40 anesthesiology residents who participated in fiberscope simulation training at Ruijin Hospital, Shanghai Jiaotong University School of Medicine between November 2022 and March 2023 were selected for this study. They were randomly divided into two groups (Group S and Group M) using a numerical table method. The teaching was completed using two orders of key techniques. The operation time, operation quality score, and theoretical knowledge mastery score of the two groups were recorded to compare the effect of key technique learning order on the mastery of fiberoptic skills. SPSS 29.0 statistical software was used for data analysis. Measurement data that conformed to normal distribution were expressed as mean ± standard deviation, and the independent samples t-test or Fisher's exact test were used for comparison between groups. The chi-square test was used for comparison of enumeration data. Results:After segmented training in each key technique, both groups of trainees were able to shorten the operation time of the corresponding key technique [SM simulator operation time (132.25±14.69) s vs. (49.80±4.46) s in group S, P<0.01; M simulator operation time (82.30±11.60) s vs. (57.10±6.77) s in group S, P<0.01; SM simulator operation time (83.10±10.62) s vs. (52.10±5.20) s in group M, P<0.01; M simulator operation time (132.25±14.69) s vs. (55.40±5.91) s in group M, P<0.01)]. Moreover, both groups showed a reduced number of wall touches [SM simulator wall touches (3.35±0.93) times vs. (0.65±0.49) times in group S, P<0.01; M simulator wall touches (2.50±1.05) times vs. (0.70±0.80) times in group S, P<0.01; SM simulator wall touches (1.55±1.15) times vs. (0.40±0.50) times in group M, P<0.01; M simulator wall touches (5.90±1.29) times vs. (1.10±0.79) times in group M, P<0.01]. There were no significant differences between the two groups in the performance score of fiberoptic-guided tracheal intubation after training [(92.50±5.97) points vs. (91.75±5.45) points] and in the lung segment localization time [(23.15±4.39) s, (21.40±4.84) s, (22.85±4.42) s vs. (22.75±5.11) s, (21.00±5.40) s, (21.50±5.10) s]. Conclusions:Segmented training on key fiberoptic bronchoscopy techniques is an effective model of fiberscope training for anesthesiology residents, and the order of training key techniques does not affect the effectiveness of training.

Objective:To discuss the feasibility of the viscosity determination method in the registration standard of type IB magnesium aluminum silicate.Methods:Two different types of high speed blender and rotary viscometer were used to investigate the viscosity of IB-type magnesium aluminum silicate.Results:When the viscosity of mag-nesium aluminum silicate(IB type)was investigated by rod high-speed stirrer and rotary viscometer,the samples did not meet the requirements.When the viscosity of magnesium aluminum silicate(IB type)was investigated by wall breaker and rotary viscometer,the samples met the requirements.Conclusion:IB type magnesium aluminum silicate is a thixotropic non-newtonian fluid,and the viscosity measurement results of it are greatly affected by the high speed blender.It is recommended that the type of high speed blender which is suitable for use in the test should be specified.

This experiment aims to investigate the effects of a dietary supplement of herbal tea resi-due on white feather broilers in the prospectives of growth performance,serum indexes and intesti-nal immune indexes.A total of 280 1-day-old white feather broilers with similar body mass and good health were randomly divided into 4 groups with 5 replicates per group and 14 birds per repli-cate.Group Ⅰ(control group)was fed a basal diet.Groups Ⅱ,Ⅲ and Ⅳ were fed a diet supple-mented with 2％,4％and 6％herbal tea residue powder,respectively.The feeding lasted for 49 days,and was divided into 2 phases from 1 to 21 days of age and 22 to 49 days of age.Blood,tissue and mucosa of the duodenum and jejunum were collected on 21 d and 49 d.Total cholesterol(T-CHO),triglyceride(TG),high density lipoprotein cholesterol(HDL-C),low density lipoprotein cholesterol(LDL-C)and the activities of aspartate aminotransferase(AST)and alanine amin-otransferase(ALT)in the serum were examined.The villus height and crypt depth of the jejunum were observed and measured by morphology.The mRNA expression levels of intestinal interleukin-1β(IL-1β),interleukin-2(IL-2),interleukin-4(IL-4),interleukin-10(IL-10)and tumor necrosis factor-α(TNF-α)were determined by qPCR.The results showed that compared with group Ⅰ,the mass of group Ⅲ on 21 d and 49 d significantly increased(P＜0.05).The average daily feed intake of 22-49 d and 1-49 d significantly increased(P＜0.05).The average daily mass gain of 1-21 d,22-49 d and 1-49 d significantly increased(P＜0.05).In the serum of 21 d,compared with group Ⅰ,T-CHO in group Ⅱ significantly decreased(P＜0.05).TG in groups Ⅱ,m and Ⅳ significantly de-creased(P＜0.05).LDL-C and AST activity in group Ⅳ significantly decreased(P＜0.05).In the serum of 49 d,T-CHO in group Ⅲ,LDL-C in group Ⅳ,HDL-C of groups Ⅲ and Ⅳ significantly increased(P＜0.05),and the ALT activity of these two groups decreased(P＜0.05).AST activity in group Ⅱ significantly decreased(P＜0.05).In the duodenum of 21 d,compared with group Ⅰ,the expressions of TNF-α in group Ⅱ was significantly decreased(P＜0.05).In the duodenum of 49 d,the expression of IL-10 in group Ⅱ was significantly increased(P＜0.05),and the expression of IL-2 in groups Ⅲ and Ⅳ was significantly decreased(P＜0.05).In the jejunum of 49 d,the ex-pression of IL-10 in group Ⅱ was increased(P＜0.05),and the expression of IL-2 in groups Ⅲand Ⅳ was significantly decreased(P＜0.05).In conclusion,dietary herbal tea residue can regulate circulating lipid level and enhance intestinal immunity of white feather broilers without affecting their normal growth performance.This experiment also suggested that the a 2％-4％supplementa-tion of herbal tea residues to white feather broilers was of good effect.

Objective:To explore the risk factors affecting the survival and efficacy of patients with acute myeloid leukemia with myelodysplasia-related changes(AML-MRC)transformed from myelodysplastic syndrome(MDS).Methods:The clinical data of 60 patients with AML-MRC transformed from MDS who hospitalized in The Third Affiliated Hospital of Soochow University from January 2010 to December 2021 were retrospectively analyzed.The demographic data and laboratory parameters,cytogenetic karyotypes,target genes of AML detected by next generation sequence,risk stratification,treatment regimen,therapeutic efficacy and survival outcome were documented.Rank sum test and Chi-square test or Fisher exact test were used to compare the survival and efficacy.The effects of clinical parameters,risk stratification and treatment regimens on the survival and efficacy of the AML-MRC patients were analyzed by univariate and multivariate analysis.Results:The median overall survival(OS)of the AML-MRC patients was 4.5 months,the 1-year OS rate was 28.3％,and the complete remission(CR)rate after treatment was 33.3％.The univariate analysis showed that age≥60 years,leukocytosis,severe thrombocytopenia,poor-risk group and only accepted hypomethylating agents(HMAs)or supportive therapy were the risk factors affecting OS.COX multivariate analysis showed that thrombocytopenia(HR=4.46),HMAs therapy(compared to transplantation,HR=10.47),supportive therapy(compared to transplantation,HR=25.80)and poor-risk group(compared to medium-risk group,HR=13.86)were independent hazard factors for median OS of patients with AML-MRC.The univariate analysis showed that the risk factors affecting 1-year OS in patients with AML-MRC were age ≥ 60 years,thrombocytopenia,time of transformation from MDS to AML(TTA)≥3 months,fibrinogen-albumin ratio index(FARI)≥ 0.07,CONUT score≥5,poor-risk group and supportive therapy.Binary logistic regression analysis showed that the independent risk factors for 1-year OS in AML-MRC patients were age ≥ 60 years(HR=11.23),thrombocytopenia(HR=8.71),FARI ≥ 0.07(HR=5.19)and poor-risk group(HR=14.00).The risk factors affecting CR of AML-MRC patients in univariate analysis were age ≥ 60 years,thrombocytopenia,FARI ≥ 0.1,CONUT score ≥ 5,poor-risk group and supportive therapy,while binary logistic regression analysis showed that age ≥ 60 years(HR=7.35),CONUT score ≥ 5(HR=9.60),thrombocytopenia(HR=12.05)and poor-risk group(HR=32.5)were independent risk factors affecting CR of the patients.Conclusion:The OS of AML-MRC patients is poor,old age(≥ 60 years old),supportive therapy,HMA therapy,poor-risk,thrombocytopenia,FARI ≥ 0.07 and CONUT score ≥ 5 may be associated with poor prognosis.

Objective:To establish a morphologic classification system for characterizing blast cells in patients with acute promyelocytic leukemia(APL)and analyze the correlation of different APL morphologic characteristics with conventional tests and genetic variants.Methods:Based on the morphological characteristics of APL blast cells,a classification system of 14 categories was established to characterize the inter-and intra-individual cellular morphological heterogeneity of patients.The classification system was used for the morphological analysis of 40 APL patients,and the classification results were statistically analyzed with the patients'conventional test indexes and gene variant characteristics to analyze the correlation of different APL blast cell morphological features with conventional test indexes and gene variants.Results:In the FLT3-ITD mutation-positive group,there were significantly fewer cells with regular nuclear shape,hyper granularity,and missing Auer rods(category 1)than in the FLT3 mutation-negative group(P＜0.05).The activated partial thromboplastin(APTT)was significantly longer in the group with regular nucleus compared to the group with irregular nucleus(P＜0.05).In the hypo-granular group,the APTT was also significantly longer compared to the hyper-granular group(P＜0.01),and the proportion of myeloid blast cells was relatively lower(P＜0.05).The peripheral blood white blood cell counts,D-dimer,lactate dehydrogenase and proportion of bone marrow blast cells were significantly higher in the Auer rods(-)group than Auer rods increasing group(all P＜0.05).Conclusion:The newly established morphologic classification system in this study can objectively characterize different types of APL blast cells,which helps to better assess the intra-and inter-individual heterogeneity of APL blast cells,and further use in accurately analyzing the correlation of morphological phenotypes with biological properties of APL.

BACKGROUND: Osteoarthritis (OA), a degenerative joint disorder, is a major reason of disability in adults. Accumulating evidences have proved that bone marrow mesenchymal stem cells (BMSCs)-carried exosomes play a significant therapeutic effect on OA. However, the precise regulatory network remains unknown. METHODS: OA and normal cartilage samples were acquired from patients, and chondrocytes were exposed to IL-1b to conduct a cellular OA model. Exosomes prepared from BMSCs were identified using nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM). Cell viability was determined with CCK-8 assay. Inflammatory injury was assessed by LDH and inflammatory factors (TNF-a and IL-6) using corresponding ELISA kits, respectively. Ferroptosis was evaluated by GSH, MDA and iron levels using corresponding kits, and ROS level with DCFH-DA. The expressions of genes/proteins were determined with RT-qPCR/western bolt. RNA immunoprecipitation and luciferase activity assay were conducted for testing the interactions of small nucleolar RNA host gene 7 (SNHG7)/ferroptosis suppressor protein 1 (FSP1) and miR-485-5p. RESULTS: The expressions of SNHG7 and FSP1 were both reduced in IL-1b-induced chondrocytes and OA cartilage tissues, and there was a positive correlation between them in clinical level. Moreover, SNHG7 was enriched in BMSCsderived exosomes (BMSCs-Exos) and could be internalized by chondrocytes. Functional analysis illustrated that BMSCsExos administration repressed inflammatory injury, oxidative stress and ferroptosis in IL-1b-induced chondrocytes, while these changes were reinforced when SNHG7 was overexpressed in BMSCs-Exos. Notably, FSP1 silencing in chondrocytes abolished the beneficial effects mediated by exosomal SNHG7. CONCLUSIONS Exosomal SNHG7 released from BMSCs inhibited inflammation and ferroptosis in IL-1b-induced chondrocytes through miR-485-5p/FSP1 axis. This work suggested that BMSCs-derived exosomal SNHG7 would be a prospective target for OA treatment.

AIM To establish a UPLC-MS/MS method for the simultaneous content determination of Asp,Guad,Adeno,Arg,Ade,Cyti,Phe,Leu,Ile,Glu,Ser,Gln,Gly,Ala,Hyp,Thr,Pro and Lys in Asini Corii Colla.METHODS The analysis was performed on a 45℃ thermostatic Waters BEH C18column(2.1 mm×50 mm,1.7 μm),with the mobile phase comprising of acetonitrile(containing 0.1% formic acid)-water flowing at 0.35 mL/min in a gradient elution manner,and electron spray ionization source was adopted in positive ion scanning with multiple reaction monitoring mode.Subsequently,chemical pattern recognition was performed by hierarchical clustering analysis,principal component analysis and orthogonal partial least squares-discriminant analysis.RESULTS Eighteen nucleosides and free amino acids showed good linear relationships within their own ranges(r≥0.999 0),whose average recoveries were 98.0%-104.9% with the RSDs of 1.6%-4.9% .Seventeen batches of samples were clustered into two categories,two principal components demonstrated the accumulative variance contribution rate of 60.75%,Leu,Phe,Ade and Guad were potential index constituents.CONCLUSION This stable and reliable method can be used for the quality control of Asini Corii Colla.

Hand, foot and mouth disease (HFMD) is a common infectious disease among children, and has emerged as a substantial global public health concern, particularly in the Asia-Pacific region. It has a serious impact on children′s health and imposes a significant disease burden on families and society. Currently, there are three globally available HFMD vaccines (all of them are EV71 inactivated vaccine), which were first approved and marketed in China in 2016. Real-world studies have shown a decrease in the incidence, severity, and mortality rate of EV71-related HFMD, providing evidence of its effectiveness. Additionally, related data have indicated a significant change in the pathogen spectrum of HFMD in China in the post-vaccine era. This article aims to provide a comprehensive review of the safety, effectiveness and immune-persistence data of EV71 vaccine acquired through real-world studies.