ObjectiveIn nature, objects cast shadows due to illumination, forming the basis for stereoscopic perception. Birds need to adapt to changes in lighting (meaning they can recognize stereoscopic shapes even when shadows look different) to accurately perceive different three-dimensional forms. However, how neurons in the key visual brain area in birds handle these lighting changes remains largely unreported. In this study, pigeons (Columba livia) were used as subjects to investigate how neurons in pigeon’s ventrolateral mesopallium (MVL) represent stereoscopic shapes consistently, regardless of changes in lighting. MethodsVisual cognitive training combined with neuronal recording was employed. Pigeons were first trained to discriminate different stereoscopic shapes (concave/convex). We then tested whether and how light luminance angle and surface appearance of the stereoscopic shapes affect their recognition accuracy, and further verify whether the results rely on specify luminance color. Simultaneously, neuronal firing activity of neurons was recorded with multiple electrode array implanted from the MVL during the presentation of difference shapes. The response was finally analyzed how selectively they responded to different stereoscopic shapes and whether their selectivity was affected by the changes of luminance condition (like lighting angle) or surface look. Support vector machine (SVM) models were trained on neuronal population responses recorded under one condition (light luminance angle of 45°) and used to decode responses under other conditions (light luminance angle of 135°, 225°, 315°) to verify the invariance of responses to different luminance conditions. ResultsBehavioral results from 6 pigeons consistently showed that the pigeons could reliably identify the core 3D shape (over 80% accuracy), and this ability wasn’t affected by changes in light angle or surface appearance. Statistical analysis of 88 recorded neurons from 6 pigeons revealed that 83% (73/88) showed strong selectivity for specific 3D shapes (selectivity index>0.3), and responses to convex shapes were consistently stronger than to concave shapes. These shape-selective responses remained stable across changes in light angle and surface appearance. Neural patterns were consistent under both blue and orange lighting. The decoding accuracy achieves above 70%, suggesting stable responses under different conditions (e.g., different lighting angles or surface appearance). ConclusionNeurons in the pigeon MVL maintain a consistent neural encoding pattern for different stereoscopic shapes, unaffected by illumination or surface appearance. This ensures stable object recognition by pigeons in changing visual environments. Our findings provide new physiological evidence for understanding how birds achieve stable perception (“invariant neural representations”) while coping with variations in the visual field.

Testicular histology based on testicular biopsy is an important factor for determining appropriate testicular sperm extraction surgery and predicting sperm retrieval outcomes in patients with azoospermia. Therefore, we developed a deep learning (DL) model to establish the associations between testicular grayscale ultrasound images and testicular histology. We retrospectively included two-dimensional testicular grayscale ultrasound from patients with azoospermia (353 men with 4357 images between July 2017 and December 2021 in The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China) to develop a DL model. We obtained testicular histology during conventional testicular sperm extraction. Our DL model was trained based on ultrasound images or fusion data (ultrasound images fused with the corresponding testicular volume) to distinguish spermatozoa presence in pathology (SPP) and spermatozoa absence in pathology (SAP) and to classify maturation arrest (MA) and Sertoli cell-only syndrome (SCOS) in patients with SAP. Areas under the receiver operating characteristic curve (AUCs), accuracy, sensitivity, and specificity were used to analyze model performance. DL based on images achieved an AUC of 0.922 (95% confidence interval [CI]: 0.908-0.935), a sensitivity of 80.9%, a specificity of 84.6%, and an accuracy of 83.5% in predicting SPP (including normal spermatogenesis and hypospermatogenesis) and SAP (including MA and SCOS). In the identification of SCOS and MA, DL on fusion data yielded better diagnostic performance with an AUC of 0.979 (95% CI: 0.969-0.989), a sensitivity of 89.7%, a specificity of 97.1%, and an accuracy of 92.1%. Our study provides a noninvasive method to predict testicular histology for patients with azoospermia, which would avoid unnecessary testicular biopsy.
Humans ; Male ; Azoospermia/diagnostic imaging* ; Deep Learning ; Testis/pathology* ; Retrospective Studies ; Adult ; Ultrasonography/methods* ; Sperm Retrieval ; Sertoli Cell-Only Syndrome/diagnostic imaging*

Objective To investigate the interaction between a novel antimicrobial compound,HL-J6,and penicillin-binding protein 1(PBP1)of Staphylococcus aureus.Methods With MRSA252 genomic DNA as the template and PBP1F and PBP1R as primers,the expression plasmid pET30a-pbp1-39-608 was constructed by amplifying the target gene fragment followed by cloning into the Nde I/Xho I restriction sites of the pET30a vector.Then the obtained plasmids were transformed into Escherichia coli for the expression of PBP1-39-608 protein,and the product was purified by affinity chromatography.The inhibitory effect of HL-J6 on the transpeptidase activity of PBP1-39-608 was measured using peptidoglycan side chain backbone peptide,with thiol ester analog S2d as the substrate.The affinity between HL-J6 and PBP1-39-608 was detected using microscale thermophoresis(MST),and the binding interaction was confirmed by cellular thermal shift assay(CETSA).Molecular docking and dynamics simulation were performed using AutoDock Vina and Desmond software,respectively,to elucidate the binding mode of HL-J6 with the PBP1-39-608 protein and the key amino acid residues involved.Results The recombinant plasmid pET30a-pbp1-39-608 was successfully constructed,and PBP1-39-608 protein was produced after induction and purified,yielding a protein with an approximate molecular mass of 65×103.HL-J6 inhibited the transpeptidase activity of PBP1-39-608 in a time-dependent manner(P<0.001).The dissociation constant Kd of the binding between HL-J6 and PBP1-39-608 was 64.92 μmol/L.Molecular docking results showed that HL-J6 bound to the active pocket of PBP1-39-608 by interacting with key residues such as ILE-348,ASN-370,THR-516 and PHE-423,with a binding score of-8.38 kcal/mol(<-5.00 kcal/mol).Dynamics simulation results indicated that the complex became stable after 50 ns.Conclusion HL-J6 effectively inhibits the transpeptidase activity of Staphylococcus aureus PBP1,and shows stable interaction with the protein.

Objective To investigate the protective effect of Toll-like receptor (TLR)2/TLR9 agonists,Pam2 CSK4(Pam)and CpG ODN (CpG)on mice infected with Acinetobacter baumannii (Ab)in the lungs.Methods Female C57 mice (6～8 weeks old)were randomly divided into PBS,Pam,CpG and Pam+CpG groups.In 24 h after intranasal immunization with different doses of the corresponding agonists,the mice were given a lethal dose of Ab infection in the lungs,and the survival rates of the mice were observed.A sublethal dose lung infection model of Ab was then established,and the bacterial colonization in the blood,lungs,liver,kidneys and spleen was measured respectively in the mice after infection.HE staining was used to observe the pathological damages in the lungs and kidneys.The protective effect of the agonists in the immunized mice against Ab was examined at 1,3 and 7 d after immunization to explore the protective time window.Pam+CpG was used to stimulate A549 cells and RAW264.7 cells to investigate the killing or phagocytic effects on Ab.Results Compared to PBS,Pam+CpG treatment significantly improved the survival rate of the mice after a lethal dose of Ab lung infection (P<0.05,P<0.01 ),reduced bacterial colonization in the blood (P<0.01 ),lungs (P<0.01 ),liver (P<0.01 ),kidneys (P<0.01 )and spleen (P<0.01 )in the mice after sublethal challenge,and alleviated pathological damage caused by infection. Immunization at 1 or 3 d before infection significantly improved the survival rate (P<0.05 ),and the protective effect was the best in 3 d after immunization.Furthermore,compared to single PBS,Pam and CpG immunization,Pam+CpG significantly promoted the killing and phagocytic effects of A549 epithelial cells and RAW264.7 cells,respectively,against Ab (P<0.01 ).Conclusion Combined application of TLR2/TLR9 agonists exerts a significant protective effect on both lethal and sublethal infections of Ab,which might be by its promoting the killing or phagocytic effect of lung epithelial cells and macrophages against Ab.

Objective To construct lipid nanoparticles(lipopeptide-lipid nanoparticle,LP-LNP)with novel lipopeptides as adjuvants,and initially explore their synergistic effect on mRNA vaccines.Methods Two novel lipopeptides,SS-10 and SQ18,were designed and synthesized.Microfluidic technology was used to encapsulate lipopeptides in different proportions,as well as mRNAs encoding enhanced green fluorescent protein(eGFP),firefly luciferase(F-luc),and ovalbumin(OVA)into lipid nanoparticles to construct an mRNA delivery system with novel lipopeptides as adjuvants(LP-LNP).The particle size and polydispersity coefficient of LP-LNP were measured using dynamic light scattering.The activation effect on Toll-like receptors 2(TLR2)was detected using HEK-BlueTM mTLR2 reporter cells to screen the optimal lipopeptide ratio.The preferred LP-LNP-eGFP-mRNA was transfected into HEK293T cells,and the expression of eGFP was observed under a fluorescence microscope.In vivo imaging was used to investigate the expression level of LP-LNP-F-luc-mRNA in mice.Flow cytometry was used to evaluate the ability of LP-LNP-OVA-mRNA to induce the maturation of dendritic cells(DCs)in draining lymph nodes and cross-presentation of antigens after immunization.Results Lipopeptides SQ18 and SS-10 were incorporated into LNP at 0.50％and 0.75％molar ratios,respectively,to obtain LP-LNP with uniform particle size,high encapsulation efficiency,and good in vitro safety.The ability of this formulation to activate TLR2 was significantly stronger than the positive control Pam2CSK4(P＜0.01).The preferred LP-LNP obtained effective in vitro transfection,and LP-LNP prepared with SQ18 at 0.50％molar ratio had significantly better in vivo transfection efficiency than traditional LNP(P＜0.01),and significantly promoted the maturation of DCs in draining lymph nodes and cross-presentation of antigens(P＜0.05).Conclusion LP-LNP with novel lipopeptides as adjuvants can enhance the delivery capacity of mRNA and further improve the immune effect of mRNA vaccines.

Objective:To investigate the accuracy of next-generation sequencing technology(NGS)in detecting the polymorphisms of HLA-DRB1,DQB1,DQA1,DRB3,DRB4,DRB5,DPA1 and DPB1 alleles in randomly-selected unrelated healthy individuals from Shenzhen Han population,investigate the potential reason for HLA-DRB1 allele dropout in routine NGS,and establish an internal quality control system.Methods:NGS-based HLA class Ⅱ genotyping was performed on 1 012 samples using the MiSeqDxTM platform.The suspected missed alleles indicated by the quality control software and HLA-DRB1 homozygotes were confirmed by PCR-SSOP or PCR-SBT methods.Results:A total of 139 alleles were detected,including HLA-DRB1(45),DRB3(7),DRB4(5),DRB5(7),DQA1(17),DQB1(21),DPA1(10)and DPB1(27).HLA-DRB 1*09:01(17.09％),15:01(10.72％);DRB3*02:02(25.99％),03:01(10.18％);DRB4*01:03(36.46％);DRB5*01:01(15.42％);DQA1*01:02(20.01％),03:02(17.19％);DQB1*03:01(19.47％),03:03(17.98％),05:02(11.66％),06:01(10.67％);DPA1*02:02(54.45％),01:03(31.18％)and DPB1*05:01(39.13％),02:01(16.90％)alleles were the most common alleles in Shenzhen Han population(frequencies＞10％).There was no statistical difference between the gene frequencies of HLA-DRB1 and DQB1 loci in our study.The HLA Common and Well-Documented Alleles in China(CWD2.4)(x2=12.68,P＞0.05).94 cases of HLA-DRB1 homozygous samples detected by NGS were retested by PCR-SSOP or SBT method,and one case of allele dropout at HLA-DRB1 locus was found.SBT method confirmed that the allele of DRB1*04:03 was missed.The laboratory internal quality control system was established.Two cases of new alleles were detected and named by WHO Nomenclature Committee for Factors of the HLA System.Conclusion:The HLA genotyping results based on NGS showed a significantly lower ambiguity rate.The HLA class Ⅱ alleles exhibit genetic polymorphism in the Han population of unrelated healthy individuals in Shenzhen.The independent method based on NGS in clinical histocompatibility testing has limitations and requires internal quality control strategies to avoid allele-dropout events.

Objective:Empirical analysis of the multiple driving paths of service capabilities of home-and community-based integrated health and social care in China,for providing useful reference for promoting the system improvement.Methods:Based on the World Health Organization's Integrated Care for Older People(ICOPE)implementation framework,an analysis framework for service capabilities of home-and community-based integrated health and social care was constructed.39 districts(counties)in Wuxi,Jiaozuo,Changsha,Chengdu,and Chongqing were included.The fuzzy-set qualitative comparative analysis(fsQCA)method was used to analyze the configuration paths of high or non-high-level service capabilities of home-and community-based integrated health and social care.Results:The service capabilities of home-and community-based integrated health and social care is improved by the configuration of various factors.Four path configurations might contribute to the development of service capabilities of home-and community-based integrated health and social care,and three path configurations might hinder the development.Institutional support,financing mechanism and the demand level of regional aging population are the key factors.Conclusions:Service capabilities of home-and community-based integrated health and social care are affected by the interaction and interrelation between multiple factors.Strategies should be jointly implemented from different aspects to improve service capabilities.

Objective:To explore the differential impact of the alignment between service capability and job satisfaction on job performance among primary general practitioner,and to provide a reference for enhancing their job performance.Methods:A survey was conducted with 620 primary general practitioner using questionnaires.The relationships among service capability,job satisfaction,and job performance were analyzed using polynomial regression and response surface analysis methods.Results:Under the condition of"service capability—job satisfaction alignment,"compared to the scenario of"low service capability—low job satisfaction,"primary general practitioner with"high service capability—high job satisfaction"demonstrated significantly higher job performance(a1=0.875,P＜0.001;a2=-0.068,P＞0.05).In the misalignment condition,compared to"low service capability—high job satisfaction,"those with"high service capability—low job satisfaction"also showed higher job performance(a3=0.265,P＜0.001;a4=-0.064,P＞0.05).Conclusion:Both service capability and job satisfaction significantly influence job performance among primary general practitioner,with service capability being a key factor for achieving high work performance.It is essential to enhance the service capability of primary general practitioner and adopt multiple strategies to improve job satisfaction,thereby effectively boosting work performance.

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.