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.

[This corrects the article DOI: 10.1016/j.apsb.2024.03.030.].

The aim of this study was to investigate the virulence determinants and genetic diversity of foodborne Yersinia enterocolitica from Wenzhou.A total of 71 strains of Yersinia enterocolitica were isolated from food and foodborne diarrhea ca-ses in Wenzhou,and their biotypes,serotypes,and drug resistance were analyzed.On the basis of whole genome sequencing,we assessed virulence gene profiles,and performed multilocus sequence typing(MLST)and core gene multilocus sequence typ-ing(cgMLST).A total of 94.4％(67/71)of isolates belonged to biotype 1A,and the highest proportion had serotype lA/O∶5(29.6％,21/71).The sensitivity rates of the isolates to 14 antibiotics exceeded 95.8％.A total of 16 categories and 126 viru-lence genes were identified,with two strains carrying the pYV plasmid and chromosome-related virulence genes.ST3(31.6％,12/38)was the most widespread MLST type,and cgMLST analysis revealed no dense clusters of genotypes except for strains sharing the same ST.In conclusion,pathogenic strains were identified from foodborne Yersinia enterocolitica in Wenzhou and were found to exhibit high genetic polymorphism.Enhanced regulatory supervision is essential to prevent the outbreak of food-borne diseases caused by Yersinia enterocolitica.

Objective To investigate the effects of different culture conditions(RPMI-1640,DMEM and DMEM/F12 medium)on the passage of MPM cells isolated from the tissues of Malignant pleural mesothelioma(MPM),and to study the effects of CDKN2B on the proliferation,invasion and apoptosis of MPM cells.Methods MPM cells were isolated from MPM tissues and cultured in RPMI-1640,DMEM and DMEM/F12 medium,respectively.Cell proliferation was examined by CCK-8,and the nuclei and chromosomes were observed by Wright-Giemsa staining.Fluorescence intensities of Calretinin,CD141,CK5,EMA and WT-1 were conducted by immunofluorescence assay.The mRNA and protein expression of CDKN2B were detected by RT-qPCR and Western blot,respectively.Transwell was used to detect cell invasion and flow cytometry was used to detect cell apoptosis.Results The established MPM cells showed good viability when passaged to the 10th generation in RPMI-1640,DMEM and DMEM/F12 cultures,and the MPM markers Calretinin,CD141,CK5,EMA and WT-1 were all expressed in the cells.The viability of MPM cells in RPMI-1640 culture medium was relatively stable.CDKN2B was downregulated in MPM cells(P<0.05),and overexpression of CDKN2B significantly suppressed the proliferation(P<0.05),invasion(P<0.05)and epithelial interstitial transformation of MPM cells(P<0.01),and promoted the apoptosis(P<0.01).Conclusion The established MPM cells were stably passaged in RPMI-1640 culture medium,and CDKN2B may be a potential target for the diagnosis and treatment of MPM.

Objective:To explore the potential impact of lipid metabolism-related single nucleotide polymorphisms(SNP)on semen quality in men.Methods:We selected 284 semen samples from Xingtai Infertility Hospital and Hebei Human Sperm Bank collected between February and October 2023,33 from oligozoospermia(OS),97 from asthenozoospermia(AS)and 54 from oligoas-thenozoospermia(OAS)patients and the other 100 from normal men.We performed computer-assisted semen analysis(CASA)of the samples,extracted blood DNA and,using the Mass ARRAY? System,genotyped the target genes,determined the genotypes of 13 SNPs and compared their distribution,their correlation with BMI and semen quality in different groups.Results:The mutant homozygous(TT)genotype of the FADS2 rs2727270 gene seemed to be a risk factor for AS(OR=4.420,P=0.047),while the APOA2 rs5082-A allele and MC4R rs17782313 heterozygous(TC)genotype important protective factors for OS(OR=0.422 and 0.389;P=0.045 and 0.043,respectively).A significantly higher sperm concentration was found associated with the MC4R rs17782313 heter-ozygous(TC)genotype than with the homozygous(CC)genotype.Stratification analysis showed that the protective effect of the TC genotype was decreased with increased BMI and remained with the interaction of the rs5082 and rs17782313 genotypes.Conclusion:FADS2 rs2727270,APOA2 rs5082 and MC4R rs17782313 were significantly correlated with the risk of abnormal semen parameters.

Purpose: Polyacrylamide hydrogel (PAHG), which had been used widely for breast augmentation, has been banned for more than 15 years. Patients who had been injected PAHG for breast augmentation need evacuation surgery to remove as much as possible. To provide a series of diagnosis and treatment process MRI and intraoperative color Doppler ultrasound are combined for maximal removal of PAHG. Methods: The patients who received evacuation surgery in Peking University Third Hospital from 2010 to 2022 after PAHG injection for breast augmentation were included in this research. MR scanning was performed preoperatively and postoperatively in some of these patients and color Doppler ultrasound was applied to help evacuate PAHG intraoperatively. The mean clearance rate of PAHG was calculated according to the MRI outcomes. Results: Two hundred and 4 patients had received evacuation surgery after PAHG injection for breast augmentation with an average age of 42.8 years and an average body mass index of 21.2 kg/m 2 . The average PAHG retention time was 13.5 years. Among them, 52 patients underwent pre- and postoperative MRI scanning. The mean three-dimensional (3D) volume of PAHG was 684.8 mL (range, 350.0–1,123.9 mL), and the average residual 3D volume of PAHG was 53.7 mL (range, 12.4–98.3 mL). The mean clearance rate was 92.1%. Conclusion MRI and intraoperative color Doppler ultrasound can provide effective and precise location information of PAHG for evacuation surgery, which is a reliable method to ensure the maximal removal of PAHG.

Glyceryl phenylbutyrate(GPB)serves as a long-term management medication for Ornithine transcarbamylase deficiency(OTCD),effectively controlling hyperammonemia,but there is a lack of experience in using this medicine in China.This article retrospectively analyzes the case of a child diagnosed with OTCD at Shanghai Children's Medical Center,Shanghai Jiao Tong University School of Medicine,including a review of related literature.After diagnosis,the patient was treated with GPB,followed by efficacy follow-up and pharmacological monitoring.The 6-year and 6-month-old male patient exhibited poor speech development,disobedience,temper tantrums,and aggressive behavior.Blood ammonia levels peaked at 327 μmol/L;urine organic acid analysis indicated elevated uracil levels;cranial MRI showed extensive abnormal signals in both cerebral hemispheres.Genetic testing revealed de novo mutation in the OTC gene(c.241T＞C,p.S81P).Blood ammonia levels were approximately 43,80,and 56 μmol/L at 1,2,and 3 months after starting GPB treatment,respectively.During treatment,blood ammonia was well-controlled without drug-related adverse effects.The patient showed improvement in developmental delays,obedience,temperament,and absence of aggressive behavior.

To clarify the content characteristics of the main active components and mineral elements of Cynomorium songaricum under different habitat conditions, and further explore the relationship between the quality of C. songaricum and habitats, this study took C. songaricum from 25 different habitats in China as the research object, and measured the contents of 8 main active components and 12 mineral elements separately. Diversity analysis, correlation analysis, principal component analysis and cluster analysis were carried out. The results showed that the genetic diversity of total flavonoids, ursolic acid, ether extract, potassium(K), phosphorus(P) and zinc(Zn) in C. songaricum was high. The coefficient of variation of crude polysaccharide, ether extract, gallic acid, protocatechuic aldehyde, catechin, epicatechin, calcium(Ca), sodium(Na), magnesium(Mg), sulfur(S), iron(Fe), manganese(Mn), selenium(Se) and nickel(Ni) were all over 36%, indicating that the quality of C. songaricum was significantly affected by habitats. There were strong synergistic and weak antagonistic effects among the contents of the 8 active components, and complex antagonistic and synergistic effects among the contents of the 12 mineral elements. Principal component analysis revealed that crude polysaccharide, ursolic acid, catechin, epicatechin and total flavonoids could be used as the characteristic components to evaluate the quality of C. songaricum, and Na, copper(Cu), Mn and Ni were the characteristic elements to evaluate the quality of C. songaricum. In cluster ana-lysis, the second group with the main active components as cluster center had better quality in terms of the content of active substances, and the second group with the mineral elements as cluster center had higher utilization potential in the exploitation of mineral elements. This study could provide a basis for resource evaluation and breeding of excellent varieties of C. songaricum in different habitats, and provide a reference for cultivation and identification of C. songaricum.
Cynomorium ; Catechin ; Plant Breeding ; Selenium ; Ethers ; Ethyl Ethers ; Flavonoids ; Plant Extracts