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.

Pancreatic cancer is a kind of highly malignant tumor with a low survival rate and poor prognosis. The effectiveness of gemcitabine as a first-line chemotherapy drug is limited; however, it can activate dendritic cells and improve antigen presentation which increase the sensitivity of tumor cell to immunotherapy. Although immunotherapy has made some advancements in cancer treatment, the therapeutic benefit of programmed cell death receptor 1/programmed death receptor-ligand 1 (PD-1/PD-L1) blockade therapy remains relatively low. The chemokine C-X-C chemokine ligand 12 (CXCL12) contributes to an immunosuppressive tumor microenvironment by recruiting immunosuppressive cells. The receptor C-X-C motif chemokine receptor 4 (CXCR4), highly expressed in various tumors including pancreatic cancer, plays a crucial role in tumor development and progression. In this study, the anti-tumor immune response of human peripheral blood mononuclear cell (hPBMC) was enhanced using the combination of BsNb PX4 (anti-PD-L1&CXCR4 bispecific nanobody) and gemcitabine. In a co-culture system of gemcitabine-pretreated hPBMCs with tumor cells, the BsNb PX4 synergized gemcitabine to improve the cytotoxic activity of hPBMCs against tumor cells. Flow cytometry analysis confirmed increased ratio of CD8⁺ to CD4⁺ T cells in combination treatment. In NOD/SCID mice bearing pancreatic cancer, the combination treatment exhibited more infiltration of CD8⁺ T cells into tumor tissues, contributing to an effective anti-tumor response. This study presents potential new therapies for the treatment of pancreatic cancer. Ethical approval was obtained for collection of hPBMC samples from the Local Ethics Committee of Shanghai Jiao Tong University. All animal experiments were approved by the Animal Ethic Committee of Shanghai Jiao Tong University (authorizing number: A2024246).

OBJECTIVE To provide medication reference for duloxetine use in clinical settings， particularly for patients with depression in primary medical institutions in Xinjiang that lack therapeutic drug monitoring conditions. METHODS The medical records of 281 depression inpatients taking duloxetine in the First Affiliated Hospital of Xinjiang Medical University from January 2022 to December 2023 were retrospectively collected. They were divided into training set （196 cases） and test set （85 cases） in the ratio of 7∶3. Feature selection was performed by encapsulating random forests （RF） with recursive feature elimination. Four machine learning algorithms， namely support vector machine， RF， extreme gradient boosting （XGBoost） and artificial neural network， were used to construct duloxetine blood concentration prediction model. The prediction performance of the models was evaluated and compared by coefficient of determination （R2）， mean absolute error （MAE） and root mean squared error （RMSE）. The feature of the selected optimal model was explained by Shapley additive explanation method， and the importance ranking of the features and the influence on the prediction results of duloxetine blood concentration were determined. RESULTS A total of 29 characteristic variables were selected， including age， ethnicity， body mass index（BMI）， etc. XGBoost showed the highest R2 （0.808）， and the lowest MAE （7.644） and RMSE （10.808）. The ranking of feature importance for predicting the blood concentration of duloxetine was as follows： BMI＞age＞other 20 feature sets （including liver and kidney function and biochemical indicators）＞daily dosage＞comorbidities＞combination therapy＞ethnicity＞white blood cell count＞hemoglobin＞height. CONCLUSIONS XGBoost model possesses the best prediction performance of duloxetine blood concentration； BMI and age have a greater impact on the prediction of duloxetine blood concentration.

Objective To explore the efficacy of high tibial osteotomy(HTO)combined with medial meniscus centraliza-tion in knee osteoarthritis.Methods A total of 26 patients who underwent surgery from October 2018 to October 2020 were re-viewed.Among them,14 patients underwent high tibial osteotomy combined with arthroscopic meniscus centralization surgery were centralized group,including 8 males and 6 females,with an average age of(50.2±1.4)years old and follow-up time of(16.8±4.0)months.Twelve patients with high tibial osteotomy were in the control group,including 6 males and 6 females,with an average age of(50.9±1.8)years and follow-up time of(19.0±4.8)months.Operation time,the knee Lysholm score,knee 2000 IKDC score,MRI,femoral tibial angle(FTA),hip knee ankle angle(HKA),and intraoperative and postoperative compli-cations were recorded.Results All the incisions healed without any complication.The operation time in the centralized group was longer than that in the control group[(65.0±2.1)min vs(52.0±2.1)min,P＜0.05].The medial meniscus extrusion reduction value in the centralized group was significantly reduced compared with the control group[(2.8±1.4)mm vs(1.1±2.2)mm,P＜0.05].The FTA,HKA,knee Lyshlom score,and 2000 IKDC score between two groups were no significantly(P＞0.05).Postop-erative knee Lyshlom score and knee 2000 IKDC score improved in both groups(P＜0.05).Conclusion HTO combined with centralization of medial meniscus can improve the reduction of medial meniscus and improve knee function.The medium and long-term curative effect still needs long-term follow-up of more cases.

Objective To retrospectively analyze the ultra-fast track anesthesia(UFTA)methods and perioperative anesthesia management experiences of transcatheter mitral valve edge-to-edge repair(TEER)in the treatment of functional mitral regurgitant.Methods In this retrospective study,patients underwent the TEER procedure and received UFTA in Fuwai Yunnan Hospital,from May 2022 to September 2022 for heart failure combined with moderate to severe or severe functional mitral regurgitant were included.Baseline,preoperative complications,cardial function and anesthesia classification,amino-terminal probrain natriuretic peptide(NT-proBNP),ultrasound examination results,surgery time,extubation time,intraoperative anesthetic and vasoactive drug,complications related to TEER and UFTA,perioperative,and postoperative 30-day and one-year follow-up data were collected.All perioperative clinical data were recorded and analyzed.Results A total of 30 patients were enrolled,11 patients(36.7％)were female,mean age was(63.6±6.1)years,NYHA classification IV 14 patients(46.7％),left ventricular ejection fraction(LVEF)(36.0±8.1)％,the end-diastolic volume of the left ventricle(66.0±8.2)mm,mitral regurgitation 4+14 patients(56.7％),3+17 patients(43.3％),NT-proBNP(1 934.1±1 973.5)pg/ml,1 patient(3.3％)used high-dose vasoactive drugs during surgery.All patients did not experience nausea,vomiting,delirium,respiratory depression,perioperative transesophageal echocardiography-related gastrointestinal bleeding,pericardial effusion,cerebrovascular accidents,emergency surgery or secondary intervention,or other serious adverse events within 24 hours after surgery.No 30-day all-cause death occurred;the mean postoperative hospital stay was(7.4±2.8)days.All patients completed one-year follow-up,LVEF(37.6±11.1)％,the end-diastolic volume of the left ventricle(63.2±8.6)mm,mitral regurgitation 2+7 patients(23.3％),1+23 patients(76.7％),NT-proBNP(1 949.2±2 576.6)pg/ml.Conclusions Ultra-fast track anesthesia can be safely applied to TEER in treating functional mitral regurgitant patients.

This study analyzed the clinical characteristics of Chlamydia psittaci(C.psittaci)pneumonia to improve clinical understanding of the disease,and its diagnosis and treatment.A retrospective analysis was conducted on clinical data from 65 patients diagnosed with C.psittaci pneumonia admitted to the First Affiliated Hospital of Nanchang University between De-cember 2019 and September 2022.The patients'basic data,clinical manifestations,laboratory examination,chest CT findings,treatment,and prognosis were analyzed.The average age of the 65 patients was 58 years,and the incidence was high-est in autumn and winter.The main manifestations included fever,cough,and fatigue.Compared with non-severe cases,severe cases showed more significantly lower lymphocytes,platelets,and albumin,but significantly higher procalcitonin,alanine transaminase,aspartate transaminase,lactate dehydrogenase,serum creatinine,blood urea nitrogen,and D-dimer.The chest CT findings showed primarily ground glass shadow changes.The extent of lung lesions in severe cases was greater than that in non-severe cases,and all patients required respiratory support.Tetracycline and quinolone antibiotic treatments were effective.The results suggested that C.psittaci pneumonia occurs primarily in the autumn and winter,and manifests mainly as high fe-ver,cough,and elevation of multiple inflammatory markers.Most of the pulmonary imaging findings showed ground glass shadows.The organ damage was more obvious in more severe cases.After active and effective treatment,the prognosis of the disease is favorable.

AIM To study the chemical constituents of dichloromethane fraction from Hypericum perforatum L.METHODS The dichloromethane fraction from H.perforatum was isolated and purified by silica gel,ODS,Sephadex LH-20,semi-preparative HPLC and etc.The structures of obtained compounds were identified by physicochemical properties and spectral data.RESULTS Eleven compounds were isolated and identified as hypernorpoleketone A(1),α-onocerin(2),(3R)-thunberginol C(3),2-geranyloxy-1-(2-methylpropanoyl)-phloroglucinol(4),4,6-dihydroxy-2-O-(3″,7″-dimethyl-2″,6″-octadienyl)-1-(2′-methylbutanoyl)benzene(5),norhyperpalum G(6),garsubellin A(7),garsubellin B(8),(2″R/S)-kellerine C(9),kobusone(10),eriodictyol(11).CONCLUSION Compound 1 is a new compound.Compounds 2-3 are isolated from the plants of family Guttiferae for the first time.Compounds 4-10 are isolated from this plant for the first time.

The determinations of the operation mode and basic performance conformity for evaluating the electromagnetic compatibility of brain-computer interface rehabilitation robots were described based on relevant standards of the electromag-netic compatibility of medical electrical equipment.The performance deviations and their causes during the electromagnetic compatibility evaluation of brain-computer interface rehabilitation robots were analyzed with case studies,and some improve-ment suggestions were proposed accordingly.Technical references were provided for the manufacturers of brain-computer interface rehabilitation robots.[Chinese Medical Equipment Journal,2024,45(9):84-88]

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objectives:To explore the effect and possible mechanisms of mild hypothermia on interferon(IFN)-α2b-induced AC16 cardiomyocytes apoptosis. Methods:Cardiomyocytes were stimulated in ordinary temperature and mild hypothermia by IFN-α2b under different concentrations for different times.Proliferation activity of cardiomyocytes was detected by CCK-8 assay.Apoptosis was detected by flow cytometry technique.The effects of different interventions on mitochondrial morphology were examined using Mito-Tracker Green and laser scanning confocal microscope,respectively.The mitochondrial membrane potentials under different intervention conditions were detected by flow cytometry.The fusion of dynamin-related protein 1(Drp1)and mitochondria,and the effects of different interventions on the mitochondria was examined by Drp1 or mitochondrial fluorescent probes and laser scanning confocal microscope.The effects of different intervention conditions on the protein expression level of Phospho-Drp1(p-Drp1)Ser616,Drp1,cleaved poly ADP-ribose polymerase1(cleaved-PARP1),poly ADP-ribose polymerase1(PARP1)were detected by Western blot. Results:CCK-8 assay and flow cytometry results showed that IFN-α2b inhibited the proliferation and enhanced the apoptosis of AC16 cardiomyocytes in a time and dose-dependent manner,these effects could be attenuated by mild hypothermia.Mito-Tracker Green,laser scanning confocal microscope and flow cytometry results showed that the extent of damage of mitochondria with different interventions were attenuated in the setting of mild hypothermia as compared with ordinary temperature.The morphology of mitochondria remained intact and the mitochondrial membrane potentials were the highest in mild hypothermia group.Injured AC16 cardiomyocytes released Drp1 from cytoplasm to mitochondria and increased mitochondrial fission,these effects were abolished after mild hypothermia.p-Drp1 Ser616/Drp1 ratio and cleaved-PARP1/PARP1 ratio were decreased after mild hypothermia,and above effects could be reversed by mitochondrial division inhibitor-1(Mdivi-1)pretreatment. Conclusions:Mild hypothermia inhibits IFN-α2b-induced AC16 cardiomyocytes apoptosis via improving mitochondrial function.