1.The value of coronary CT angiography-based traditional features and radiomics in identification of culprit plaques to cause acute myocardial infarction
Pei NIE ; Shuo ZHANG ; Yan DENG ; Shifeng YANG ; Xinxin YU ; Kaiyue ZHI ; He ZHU ; Peng LI ; Jingjing CUI ; Wenjing CHEN ; Yanmei WANG ; Yuchao XU ; Dapeng HAO ; Ximing WANG
Chinese Journal of Radiology 2025;59(9):1017-1028
Objective:To investigate the value of coronary CTA (CCTA)-based traditional features and radiomics of plaque in the identification of culprit lesions that caused acute myocardial infarction (AMI).Methods:This was a retrospective multicenter study. From July 2016 to November 2023, a total of 344 patients from the Affiliated Hospital of Qingdao University (training cohort, n=184), Shandong Provincial Hospital Affiliated to Shandong First Medical University (validation cohort, n=88) and Qilu Hospital of Shandong University (test cohort, n=72) who received percutaneous coronary intervention (PCI) due to AMI and underwent CCTA within 48 hours of AMI were enrolled. The culprit plaques and non-culprit plaques were identified using a combination of electrocardiogram, CCTA, and angiographic findings. The vessel, plaque location, plaque type, Coronary Artery Disease-Reporting and Data System (CAD-RADS) score, high-risk plaque characteristics, plaque length, plaque volume, and burden were analyzed, and 1 904 radiomics features were extracted for each plaque. The traditional imaging model, the radiomics model, and the combined model were established by using multivariate Logistic regression analysis. The area under the receiver operating characteristic curve (AUC) was used to evaluate the performance of each model in identifying culprit lesions. The DeLong test was used for the comparison of AUC between every two models. The net reclassification index (NRI) was used to evaluate the incremental value of the combined model to the traditional imaging model and the radiomics model. The decision curve analysis (DCA) was used to assess the clinical net benefit of these models. A correlation heatmap was used to evaluate the correlation between the radiomics score and traditional CCTA factors. The interpretable analysis of the decision process of the combined model was performed by the Shapley Additive exPlanations (SHAP). Results:In the validation cohort and the test cohort, the AUC of the traditional imaging model developed by the vessel, plaque type, positive remodeling and CAD-RADS score was 0.898 (95% CI 0.869-0.922) and 0.881 (95% CI 0.848-0.910), respectively. The radiomics model developed by six radiomics features was 0.863 (95% CI 0.831-0.891) and 0.863 (95% CI 0.827-0.864), respectively. The AUC of the combined model was 0.930 (95% CI 0.905-0.950)and 0.919 (95% CI 0.889-0.942), respectively. In the validation cohort and the test cohort, the AUC of the combined model was higher than that of the traditional imaging model ( Z=4.013, 4.272, P<0.001) and that of the radiomics model ( Z=4.819, 3.784, P<0.001), respectively. In the validation cohort, the combined model yielded an NRI of 20.43% (95% CI 10.43%-30.44%, P<0.001) and 20.21% (95% CI 9.62%-30.80%, P<0.001) for identifying culprit lesions compared with the traditional imaging model and the radiomics model, respectively. In the test cohort, the combined model yielded an NRI of 28.05% (95% CI 16.72%-39.38%, P<0.001) and 23.57% (95% CI 13.58%-33.56%, P<0.001) for identifying culprit lesions compared with the traditional imaging model and the radiomics model, respectively. DCA showed the combined model had the highest clinical net benefit. The correlation heatmap showed the radiomics score was not correlated or only weakly correlated with traditional CCTA factors. SHAP indicated the radiomics and CAD-RADS score contributed significantly to the model. Conclusion:The CCTA-based traditional features and radiomics of plaque have favorable performance for the identification of culprit plaques in patients with AMI.
2.Efficacy and safety of a facilitated percutaneous coronary intervention with half-dose recombinant staphylokinase in ST-segment elevation myocardial infarction
Tian-yu WU ; Wen-hao ZHANG ; Peng-sheng CHEN ; Chen LI ; Tian WU ; Zhan LÜ ; Tong WANG ; Kun LIU ; Zhi-wen TAO ; Xiao-xuan GONG ; Liang YUAN ; Yong LI ; Bo CHEN ; Xin CHEN ; Zeng-guang CHEN ; Nai-quan YANG ; Yuan-yuan SANG ; Xiao-yan WANG ; Bai-hong LI ; Li ZHU ; Guo-yu WANG ; Xin ZHAO ; Chuan LU ; Jun JIANG ; Rui-na HAO ; Chun-jian LI
Chinese Journal of Interventional Cardiology 2025;33(8):431-438
Objective To investigate the clinical efficacy and safety of facilitated percutaneous coronary intervention(PCI)with half-dose recombinant staphylokinase(r-SAK)in patients with ST-segment elevation myocardial infarction(STEMI)who are expected to undergo PCI within 120 minutes.Methods From October 2021 to August 2022,a total of 200 STEMI patients in eight centers were included and randomly assigned in a 1﹕1 ratio to either r-SAK group or control group.Patients received loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive an intravenous bolus of either 5 mg r-SAK or normal saline prior to PCI.The outcomes were set as ST-segment resolution(STR)at 60-90 minutes after PCI,the proportion and transition of pathological Q waves on the 5th day after PCI,and the proportion of high-sensitivity cardiac troponin T(hs-cTnT)peaking within 12 hours of onset.The safety outcome was major bleeding events defined as Bleeding Academic Research Consortium(BARC)≥type 3 bleeding during hospitalization.Results Compared with the control group,the r-SAK group had a higher proportion of STR≥70%within 60-90 minutes after PCI(58.3%vs.40.3%,P=0.009);a lower proportion of pathological Q waves(59.1%vs.74.1%,P=0.040);a lower rate of Q wave progression(14.8%vs.43.2%,P<0.001);a higher rate of Q wave disappearance(12.5%vs.3.7%,P=0.027);and a higher proportion of hs-cTnT peaking within 12 hours of symptom onset[31/40(77.5%)vs.17/33(51.5%),P=0.027].Regarding the safety outcome,no significant difference in BARC≥type 3 bleeding was found between the two groups during hospitalization(P>0.05).Conclusions For STEMI patients who were expected to undergo primary PCI within 120 minutes of symptom onset,the facilitated PCI with half-dose r-SAK significantly increased the proportion of STR≥70%at 60-90 minutes after PCI,reduced the formation of pathological Q waves,and shortened the time to peak hs-cTnT,without increasing the risk of bleeding,which should be an alternative reperfusion strategy worthy of further study.
3.Efficacy and safety of a facilitated percutaneous coronary intervention with half-dose recombinant staphylokinase in ST-segment elevation myocardial infarction
Tian-yu WU ; Wen-hao ZHANG ; Peng-sheng CHEN ; Chen LI ; Tian WU ; Zhan LÜ ; Tong WANG ; Kun LIU ; Zhi-wen TAO ; Xiao-xuan GONG ; Liang YUAN ; Yong LI ; Bo CHEN ; Xin CHEN ; Zeng-guang CHEN ; Nai-quan YANG ; Yuan-yuan SANG ; Xiao-yan WANG ; Bai-hong LI ; Li ZHU ; Guo-yu WANG ; Xin ZHAO ; Chuan LU ; Jun JIANG ; Rui-na HAO ; Chun-jian LI
Chinese Journal of Interventional Cardiology 2025;33(8):431-438
Objective To investigate the clinical efficacy and safety of facilitated percutaneous coronary intervention(PCI)with half-dose recombinant staphylokinase(r-SAK)in patients with ST-segment elevation myocardial infarction(STEMI)who are expected to undergo PCI within 120 minutes.Methods From October 2021 to August 2022,a total of 200 STEMI patients in eight centers were included and randomly assigned in a 1﹕1 ratio to either r-SAK group or control group.Patients received loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive an intravenous bolus of either 5 mg r-SAK or normal saline prior to PCI.The outcomes were set as ST-segment resolution(STR)at 60-90 minutes after PCI,the proportion and transition of pathological Q waves on the 5th day after PCI,and the proportion of high-sensitivity cardiac troponin T(hs-cTnT)peaking within 12 hours of onset.The safety outcome was major bleeding events defined as Bleeding Academic Research Consortium(BARC)≥type 3 bleeding during hospitalization.Results Compared with the control group,the r-SAK group had a higher proportion of STR≥70%within 60-90 minutes after PCI(58.3%vs.40.3%,P=0.009);a lower proportion of pathological Q waves(59.1%vs.74.1%,P=0.040);a lower rate of Q wave progression(14.8%vs.43.2%,P<0.001);a higher rate of Q wave disappearance(12.5%vs.3.7%,P=0.027);and a higher proportion of hs-cTnT peaking within 12 hours of symptom onset[31/40(77.5%)vs.17/33(51.5%),P=0.027].Regarding the safety outcome,no significant difference in BARC≥type 3 bleeding was found between the two groups during hospitalization(P>0.05).Conclusions For STEMI patients who were expected to undergo primary PCI within 120 minutes of symptom onset,the facilitated PCI with half-dose r-SAK significantly increased the proportion of STR≥70%at 60-90 minutes after PCI,reduced the formation of pathological Q waves,and shortened the time to peak hs-cTnT,without increasing the risk of bleeding,which should be an alternative reperfusion strategy worthy of further study.
4.Construction of CD8+T cell-associated Risk Model in Hepatocellular Carcinoma Based on Bulk and Single-cell RNA-seq Data
Xin-Tong ZHANG ; Jian-Jun ZHU ; Jin WU ; Hao WU ; Fan LU ; Wen-Tao ZHANG ; Jing-Jia CHANG ; Ting TANG ; Zhi-Gao OU ; Feng-Feng JIA ; Li LI ; Peng-Fei YU ; Ming LIU
Chinese Journal of Biochemistry and Molecular Biology 2025;41(10):1511-1528
Hepatocellular carcinoma(HCC),which is essentially primary liver cancer,is closely related to CD8+T cell immune infiltration and immune suppression.We constructed a CD8+T cells related risk score model to pre-dict the prognosis of HCC patients and provided therapeutic guidance based on the risk score.Using integrated bulk RNA sequencing(RNA-seq)and single-cell RNA sequencing(scRNA-seq)datasets,we identified stable CD8+T cell signatures.Based on these signatures,a 3-gene risk score model,comprised of KLRB1,RGS2,and TN-FRSF1B was constructed.The risk score model was well validated through an independent external validation co-hort.We divided patients into high-risk and low-risk groups according to the risk score and compared the differ-ences in immune microenvironment between these two groups.Compared with low-risk patients,high-risk patients have higher M2-type macrophage content(P<0.0001)and lower CD8+T cells infiltration(P<0.0001).High-risk patients predict worse response to immunotherapy treatment than low-risk patients(P<0.01).Drug sensitivity a-nalysis shows that PI3K-β inhibitor AZD6482 and TGFβRII inhibitor SB505124 may be suitable therapies for high-risk patients,while the IGF-1R inhibitor BMS-754807 or the novel pyrimidine-based anti-tumor metabolic drug Gemcitabine could be potential therapeutic choices for low-risk patients.Moreover,expression of these 3-gene mod-el was verified by immunohistochemistry.In summary,the establishment and validation of a CD8+T cell-derived risk model can more accurately predict the prognosis of HCC patients and guide the construction of personalized treatment plans.
5.Identification of in vivo Components and Distribution Characteristics in Rats,Cardiac Tissues of Zhigancao Decoction by UP-LC-Q-TOF/MS
Zhiling TANG ; Yao LI ; Hao ZHI ; Jingyan WANG ; Xueting CAI ; Peng CAO ; Qian ZHOU
Journal of Nanjing University of Traditional Chinese Medicine 2025;41(7):896-903
OBJECTIVE To deeply explore the in vivo pharmacodynamic substance basis of Zhigancao Decoction,a classic tradi-tional Chinese medicine formula,and provide scientific evidence for its rational application and development in modern clinical practice.METHODS Wistar rats were treated with 12.15 g·kg-1 Zhigancao Decoction by gavage.Rat plasma samples were collect-ed at 10 time points(5,15,30,60,120,240,360,480,600 and 720 min after administration)and rat heart(atrial and ventricu-lar)tissue samples were collected at 12 h after administration.Components in the plasma and heart samples were qualitatively identi-fied by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF/MS),and the distri-bution characteristics of Zhigancao Decoction in vivo were analyzed.At the same time,the time-concentration curve of the prototype components and metabolites in Zhigancao Decoction was drawn to observe the changes of blood drug concentration.RESULTS A total of 11 prototype components(Ajugol,Nicotiflorin,Isoschaftoside,4-Hydroxycinnamic acid,Rehmapicrogenin,4-Hydroxybenzoic acid,4′,7-Dihydroxyflavone,Calycosin,3′,4′,7-Trihydroxyflavone,Pinellic acid,Truxillic acid)and 7 metabolites were identified from the plasma samples of Zhigancao Decoction,mainly including flavonoids(flavonoids glycosides),organic acids,and iridoid glyco-sides,etc.Additionally,6 prototype components(Ajugol,Isoschaftoside,Rehmapicrogenin,4′,7-Dihydroxyflavone,Liquiritigenin,3′,4′,7-Trihydroxyflavone)and 3 metabolites were identified from the cardiac samples(the atrium and the ventricle showed the same results).The metabolic pathways mainly involved Phase Ⅰ metabolism and glucuronidation.CONCLUSION The prototype compo-nents and metabolites in plasma and heart tissue of Zhigancao Decoction is preliminarily determined,providing a reference for analyzing the active components of Zhigancao Decoction in heart tissue.
6.Construction of CD8+T cell-associated Risk Model in Hepatocellular Carcinoma Based on Bulk and Single-cell RNA-seq Data
Xin-Tong ZHANG ; Jian-Jun ZHU ; Jin WU ; Hao WU ; Fan LU ; Wen-Tao ZHANG ; Jing-Jia CHANG ; Ting TANG ; Zhi-Gao OU ; Feng-Feng JIA ; Li LI ; Peng-Fei YU ; Ming LIU
Chinese Journal of Biochemistry and Molecular Biology 2025;41(10):1511-1528
Hepatocellular carcinoma(HCC),which is essentially primary liver cancer,is closely related to CD8+T cell immune infiltration and immune suppression.We constructed a CD8+T cells related risk score model to pre-dict the prognosis of HCC patients and provided therapeutic guidance based on the risk score.Using integrated bulk RNA sequencing(RNA-seq)and single-cell RNA sequencing(scRNA-seq)datasets,we identified stable CD8+T cell signatures.Based on these signatures,a 3-gene risk score model,comprised of KLRB1,RGS2,and TN-FRSF1B was constructed.The risk score model was well validated through an independent external validation co-hort.We divided patients into high-risk and low-risk groups according to the risk score and compared the differ-ences in immune microenvironment between these two groups.Compared with low-risk patients,high-risk patients have higher M2-type macrophage content(P<0.0001)and lower CD8+T cells infiltration(P<0.0001).High-risk patients predict worse response to immunotherapy treatment than low-risk patients(P<0.01).Drug sensitivity a-nalysis shows that PI3K-β inhibitor AZD6482 and TGFβRII inhibitor SB505124 may be suitable therapies for high-risk patients,while the IGF-1R inhibitor BMS-754807 or the novel pyrimidine-based anti-tumor metabolic drug Gemcitabine could be potential therapeutic choices for low-risk patients.Moreover,expression of these 3-gene mod-el was verified by immunohistochemistry.In summary,the establishment and validation of a CD8+T cell-derived risk model can more accurately predict the prognosis of HCC patients and guide the construction of personalized treatment plans.
7.Wdr63 Deletion Aggravates Ulcerative Colitis Likely by Affecting Th17/Treg Balance and Gut Microbiota
Hao ZHU ; Meng-Yuan ZHU ; Yang-Yang CAO ; Qiu-Bo YANG ; Zhi-Peng FAN
Progress in Biochemistry and Biophysics 2025;52(1):209-222
ObjectiveUlcerative colitis is a prevalent immunoinflammatory disease. Th17/Treg cell imbalance and gut microbiota dysregulation are key factors in ulcerative colitis pathogenesis. The actin cytoskeleton contributes to regulating the proliferation, differentiation, and migration of Th17 and Treg cells. Wdr63, a gene containing the WD repeat domain, participates in the structure and functional modulation of actin cytoskeleton. Recent research indicates that WDR63 may serve as a regulator of cell migration and metastasis via actin polymerization inhibition. This article aims to explore the effect of Wdr63 deletion on Th17/Treg cells and ulcerative colitis. MethodsWe constructed Wdr63-/- mice, induced colitis in mice using dextran sulfate sodium salt, collected colon tissue for histopathological staining, collected mesenteric lymph nodes for flow cytometry analysis, and collected healthy mouse feces for microbial diversity detection. ResultsCompared with wild-type colitis mice, Wdr63-/- colitis mice had a more pronounced shortening of colonic tissue, higher scores on disease activity index and histological damage index, Treg cells decreased and Th17 cells increased in colonic tissue and mesenteric lymph nodes, a lower level of anti-inflammatory cytokine IL-10, and a higher level of pro-inflammatory cytokine IL-17A. In addition, WDR63 has shown positive effects on maintaining intestinal microbiota homeostasis. It maintains the balance of Bacteroidota and Firmicutes, promoting the formation of beneficial intestinal bacteria linked to immune inflammation. ConclusionWdr63 deletion aggravates ulcerative colitis in mice, WDR63 inhibits colonic inflammation likely by regulating Th17/Treg balance and maintains intestinal microbiota homeostasis.
8.Biomechanical advantages of personalized Y-shaped plates in treatment of distal humeral intra-articular fractures.
Hao YU ; Jiachen PENG ; Jibin YANG ; Lidan YANG ; Zhi XU ; Chen YANG
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(5):574-583
OBJECTIVE:
To compare the biomechanical properties of personalized Y-shaped plates with horizontal plates, vertical plates, and traditional Y-shaped plates in the treatment of distal humeral intra-articular fractures through finite element analysis, and to evaluate their potential for clinical application.
METHODS:
The study selected a 38-year-old male volunteer and obtained a three-dimensional model of the humerus by scanning his upper limbs using a 64-slice spiral CT. Four types of fracture-internal fixation models were constructed using Mimics 19.0, Geomagic Wrap 2017, Creo 6.0, and other software: horizontal plates, vertical plates, traditional Y-shaped plate, and personalized Y-shaped plate. The models were then meshed using Hypermesh 14.0 software, and material properties and boundary conditions were defined in Abaqus 6.14 software. AnyBody 7.3 software was used to simulate elbow flexion and extension movements, calculate muscle strength, joint forces, and load torques, and compare the peak stress and maximum displacement of the four fixation methods at different motion angles (10°, 30°, 50°, 70°, 90°, 110°, 130°, 150°) during elbow flexion and extension.
RESULTS:
Under dynamic loading during elbow flexion and extension, the personalized Y-shaped plate exhibits significant biomechanical advantages. During elbow flexion, the peak internal fixation stress of the personalized Y-shaped plate was (28.8±0.9) MPa, which was significantly lower than that of the horizontal plates, vertical plates, and traditional Y-shaped plate ( P<0.05). During elbow extension, the peak internal fixation stress of the personalized Y-shaped plate was (18.1±1.6) MPa, which was lower than those of the other three models, with significant differences when compared with horizontal plates and vertical plates ( P<0.05). Regarding the peak humeral stress, the personalized Y-shaped plate model showed mean values of (10.9±0.8) and (13.1±1.4) MPa during elbow flexion and extension, respectively, which were significantly lower than those of the other three models ( P<0.05). Displacement analysis showed that the maximum displacement of the humerus with the personalized Y-shaped plate during elbow flexion was (2.03±0.08) mm, slightly higher than that of the horizontal plates, but significantly lower than that of the vertical plates, showing significant differences ( P<0.05). During elbow extension, the maximum displacement of the humerus with the personalized Y-shaped plate was (1.93±0.13) mm, which was lower than that of the other three models, with significant differences when compared with vertical plates and traditional Y-shaped plates ( P<0.05). Stress contour analysis showed that the stress of the personalized Y-shaped plate was primarily concentrated at the bifurcation of the Y-shaped structure. Displacement contour analysis showed that the personalized Y-shaped plate effectively controlled the displacement of the distal humerus during both flexion and extension, demonstrating excellent stability.
CONCLUSION
The personalized Y-shaped plate demonstrates excellent biomechanical performance in the treatment of distal humeral intra-articular fractures, with lower stress and displacement, providing more stable fixation effects.
Humans
;
Male
;
Adult
;
Healthy Volunteers
;
Finite Element Analysis
;
Tomography, Spiral Computed
;
Models, Anatomic
;
Biomechanical Phenomena
;
Humeral Fractures, Distal/surgery*
;
Fracture Fixation, Internal/instrumentation*
;
Bone Plates
;
Computer Simulation
;
Precision Medicine/methods*
;
Elbow Joint/surgery*
;
Elbow/surgery*
;
Humerus/surgery*
;
Torque
;
Stress, Mechanical
;
Intra-Articular Fractures/surgery*
;
Prosthesis Design/methods*
;
Imaging, Three-Dimensional
;
Range of Motion, Articular
9.Serum Lipidomics Profiling to Identify Potential Biomarkers of Ischemic Stroke: A Pilot Study in Chinese Adults.
Ji Jun SHI ; Zu Jiao NIE ; Shu Yao WANG ; Hao ZHANG ; Xin Wei LI ; Jia Ling YAO ; Yi Bing JIN ; Xiang Dong YANG ; Xue Yang ZHANG ; Ming Zhi ZHANG ; Hao PENG
Biomedical and Environmental Sciences 2025;38(8):918-925
OBJECTIVE:
Lipid oxidation is involved in the pathogenesis of atherosclerosis and may be contribute to the development of Ischemic stroke (IS). However, the lipid profiles associated with IS have been poorly studied. We conducted a pilot study to identify potential IS-related lipid molecules and pathways using lipidomic profiling.
METHODS:
Serum lipidomic profiling was performed using LC-MS in 20 patients with IS and 20 age- and sex-matched healthy controls. Univariate and multivariate analyses were simultaneously performed to identify the differential lipids. Multiple testing was controlled for using a false discovery rate (FDR) approach. Enrichment analysis was performed using MetaboAnalyst software.
RESULTS:
Based on the 294 lipids assayed, principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) models were used to distinguish patients with IS from healthy controls. Fifty-six differential lipids were identified with an FDR-adjusted P less than 0.05 and variable influences in projection (VIP) greater than 1.0. These lipids were significantly enriched in glycerophospholipid metabolism (FDR-adjusted P = 0.009, impact score = 0.216).
CONCLUSIONS
Serum lipid profiles differed significantly between patients with IS and healthy controls. Thus, glycerophospholipid metabolism may be involved in the development of IS. These results provide initial evidence that lipid molecules and their related metabolites may serve as new biomarkers and potential therapeutic targets for IS.
Humans
;
Pilot Projects
;
Lipidomics
;
Male
;
Female
;
Biomarkers/blood*
;
Middle Aged
;
Ischemic Stroke/blood*
;
Aged
;
China
;
Lipids/blood*
;
Adult
;
Case-Control Studies
;
East Asian People
10.The Invariant Neural Representation of Neurons in Pigeon’s Ventrolateral Mesopallium to Stereoscopic Shadow Shapes
Xiao-Ke NIU ; Meng-Bo ZHANG ; Yan-Yan PENG ; Yong-Hao HAN ; Qing-Yu WANG ; Yi-Xin DENG ; Zhi-Hui LI
Progress in Biochemistry and Biophysics 2025;52(10):2614-2626
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.

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