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.

AIM:To evaluate the effectiveness of EYESI binocular indirect ophthalmoscope simulation system as a training platform for fundus examination skills of general practitioner.METHODS:Prospective randomized study. A total of 40 general practitioners who received clinical ophthalmology training at Shenzhen Eye Hospital from January 2021 to December 2024 were selected and randomly divided into two groups by random number table method, with 20 cases in the study group and 20 cases in the control group. The study group was trained by EYESI binocular indirect ophthalmoscope simulation system and the control group was trained by conventional teaching. Training effects of the two groups were analyzed.RESULTS: The general information of the two groups was comparable. Through training with the EYESI binocular indirect ophthalmoscope simulator, the study group showed significant improvements in total examination and drawing scores compared to pre-training results(all P<0.001). Additionally, examination duration, retinal light exposure time, and drawing time were all significantly shorter than those before training(all P<0.001).The study group achieved significantly higher total examination and drawing scores than the control group during the EYESI binocular indirect ophthalmoscope simulator assessment(all P<0.001). Furthermore, examination duration, retinal light exposure time, and drawing time were all significantly shorter in the study group compared to the control group(all P<0.001). Moreover, ratings for the novelty of the training method and overall satisfaction with the training were significantly higher in the study group than in the control group(all P<0.001); while the perceived psychological stress during training was significantly lower in the study group(P<0.001).CONCLUSION:The EYESI binocular indirect ophthalmoscope simulaton system effectively enhances both the proficiency in fundus examination skills and overall training satisfaction among general practitioners.

Nonobstructive azoospermia (NOA), one of the most severe types of male infertility, etiology often remains unclear in most cases. Therefore, this study aimed to detect four biallelic detrimental variants (0.5%) in the minichromosome maintenance domain containing 2 ( MCMDC2 ) genes in 768 NOA patients by whole-exome sequencing (WES). Hematoxylin and eosin (H&E) demonstrated that MCMDC2 deleterious variants caused meiotic arrest in three patients (c.1360G>T, c.1956G>T, and c.685C>T) and hypospermatogenesis in one patient (c.94G>T), as further confirmed through immunofluorescence (IF) staining. The single-cell RNA sequencing data indicated that MCMDC2 was substantially expressed during spermatogenesis. The variants were confirmed as deleterious and responsible for patient infertility through bioinformatics and in vitro experimental analyses. The results revealed four MCMDC2 variants related to NOA, which contributes to the current perception of the function of MCMDC2 in male fertility and presents new perspectives on the genetic etiology of NOA.
Humans ; Male ; Azoospermia/genetics* ; Meiosis/genetics* ; Spermatogenesis/genetics* ; Adult ; Exome Sequencing ; Microtubule-Associated Proteins/genetics* ; Alleles ; Infertility, Male/genetics*

Hearing loss is the most prevalent disabling disease. Cochlear implantation（CI） serves as the primary intervention for severe to profound hearing loss. This consensus systematically explores the value of genetic diagnosis in the pre-operative assessment and efficacy prognosis for CI. Drawing upon domestic and international research and clinical experience, it proposes an evidence-based medicine three-tiered prognostic classification system（Favorable, Marginal, Poor）. The consensus focuses on common hereditary non-syndromic hearing loss（such as that caused by mutations in genes like GJB2, SLC26A4, OTOF, LOXHD1） and syndromic hereditary hearing loss（such as Jervell & Lange-Nielsen syndrome and Waardenburg syndrome）, which are closely associated with congenital hearing loss, analyzing the impact of their pathological mechanisms on CI outcomes. The consensus provides recommendations based on multiple round of expert discussion and voting. It emphasizes that genetic diagnosis can optimize patient selection, predict prognosis, guide post-operative rehabilitation, offer stratified management strategies for patients with different genotypes, and advance the application of precision medicine in the field of CI.
Humans ; Cochlear Implantation ; Prognosis ; Hearing Loss/surgery* ; Consensus ; Connexin 26 ; Mutation ; Sulfate Transporters ; Connexins/genetics*

Cemental tear is a rare and indetectable condition unless obvious clinical signs present with the involvement of surrounding periodontal and periapical tissues. Due to its clinical manifestations similar to common dental issues, such as vertical root fracture, primary endodontic diseases, and periodontal diseases, as well as the low awareness of cemental tear for clinicians, misdiagnosis often occurs. The critical principle for cemental tear treatment is to remove torn fragments, and overlooking fragments leads to futile therapy, which could deteriorate the conditions of the affected teeth. Therefore, accurate diagnosis and subsequent appropriate interventions are vital for managing cemental tear. Novel diagnostic tools, including cone-beam computed tomography (CBCT), microscopes, and enamel matrix derivatives, have improved early detection and management, enhancing tooth retention. The implementation of standardized diagnostic criteria and treatment protocols, combined with improved clinical awareness among dental professionals, serves to mitigate risks of diagnostic errors and suboptimal therapeutic interventions. This expert consensus reviewed the epidemiology, pathogenesis, potential predisposing factors, clinical manifestations, diagnosis, differential diagnosis, treatment, and prognosis of cemental tear, aiming to provide a clinical guideline and facilitate clinicians to have a better understanding of cemental tear.
Humans ; Dental Cementum/injuries* ; Consensus ; Diagnosis, Differential ; Cone-Beam Computed Tomography ; Tooth Fractures/therapy*

Metal-organic frameworks(MOFs)are porous materials composed of metal ions or metal clusters and organic ligands by coordination,which have the advantages of large specific surface area,good thermal stability and adjustable pore size,and have a promising application in gas chromatographic separation.In recent years,MOFs materials have been used as stationary phases for gas chromatography mainly including ZIF,MIL,UiO-66,HKUST-1,IRMOFs,etc.Based on the molecular sieve effect,van der Waals forces,hydrogen bonding and π-π interactions,the pore size,pore microenvironment,unsaturated metal site and special functional group of the MOFs stationary phase materials can be specifically designed and regulated.MOFs materials as stationary phases have unique separation performance for n-alkanes and their isomers,aromatic compounds and their isomers,alcohols/ketones/aldehydes and their isomers,and chiral compounds.The combination of organic polymers and novel nanomaterials with MOFs materials can improve the separation performance and stability of MOFs.Therefore,MOFs materials are expected to be the promising stationary phase that can be applied to gas separation in complex environments.In this article,the research advances of various stationary phases based on MOFs for gas chromatography in recent years were reviewed.The separation performance and separation mechanism of MOFs stationary phases for mixed gas samples were discussed,and the development trends in the future were prospected.

ObjectiveTo design a prospective nested case-control study based on a city-wide birth cohort of Shanghai， so as to understand their health status and explore the influencing factors of birth defects. MethodsBased on the birth registration covering the entire city of Shanghai， the nested case-control study of children with severe birth defects was designed. Children born with severe birth defects were selected as the case group， and healthy children were matched as the control group. Basic information， health status， maternal pregnancy history， and survival outcome of children both in the case group and the control group were collected through medical history review and home visits. The logistic regression model was used for multivariate analysis. ResultsA total of 18 875 infants born between January 1， 2011， and December 31， 2021， were included， among which 11 500 （60.93%） were children with severe birth defects and 7 375 （39.07%） were healthy children. The logistic regression model analysis showed that being male （OR=1.20， 95%CI：1.13‒1.29）， non-Shanghai residency （OR=1.16， 95%CI： 1.06‒1.25）， multiple births （OR=8.41， 95%CI：6.25‒11.30）， artificial insemination （OR=2.31， 95%CI：1.34‒3.99）， in vitro fertilization （IVF） （OR=1.85， 95%CI：1.44‒2.38）， maternal exposure to radiation （OR=1.83， 95%CI：1.07‒3.14）， maternal illness during pregnancy （OR=1.61， 95%CI：1.49‒1.74）， experiencing a traumatic event during pregnancy （OR=2.34， 95%CI：1.88‒2.92）， paternal chemical exposure （OR=1.88， 95%CI：1.32‒2.69）， paternal radiation exposure （OR=1.65， 95%CI： 1.18‒2.33）， family history of birth defects （OR=8.18， 95%CI： 3.96‒16.89）， being overweight before pregnancy （OR=1.16， 95%CI： 1.07‒1.27）， being obese before pregnancy （OR=1.15， 95%CI：1.03‒1.30）， and being excessively obese before pregnancy （OR=1.52， 95%CI：1.26‒1.83） were risk factors for the occurrence of birth defects. Analysis by type of birth defect found that prematurity was a risk factor for cardiac malformations and cheilopalatoschisis （OR=27.87， 95%CI： 20.84‒37.27）， especially ranking first in cardiac malformations. ConclusionAfter controlling for influencing factors， maternal overweight， obesity， and excessive obesity before pregnancy， artificial insemination， and IVF are independent risk factors for the occurrence of birth defects. Choosing a healthy lifestyle， improving physical and mental health during pregnancy， and controlling BMI during pregnancy are beneficial in reducing the risk of birth defects.