Bone defect repair is an urgent problem in the field of orthopedics,and numerous researchers are working to develop more effective treatment plans.The accurate evaluation of bone repair after surgery is a crucial step.In line with the development of computed tomography(CT)imaging,dual-energy CT imaging has shown significant advantages in analyzing bone composition and reducing metal artifacts.This article reviews the application of dual-energy CT imaging for the evaluation of bone repair in animals.

Bone defect repair is an urgent problem in the field of orthopedics,and numerous researchers are working to develop more effective treatment plans.The accurate evaluation of bone repair after surgery is a crucial step.In line with the development of computed tomography(CT)imaging,dual-energy CT imaging has shown significant advantages in analyzing bone composition and reducing metal artifacts.This article reviews the application of dual-energy CT imaging for the evaluation of bone repair in animals.

Objective:To assess the effect of using different thicknesses of reconstruction layer and different thicknesses of region of interest (ROI) on the results of vertebral bone mineral density (BMD) values that were measured by quantitative computed tomography (QCT). Methods:A total of 100 patients who underwent QCT screening for opportunistic osteoporosis between May and September 2021 at the First Affiliated Hospital of Zhengzhou University were retrospectively collected. Images that the thicknesses of QCT reconstruction layer were respectively 1 and 5 mm were transferred to the QCT Pro workstation,and ROI thicknesses were adjusted to 5,7,and 9 mm,respectively. The average BMD values of QCT measurements were recorded under different thicknesses of reconstruction layer and different ROI thicknesses. Then,the effects of the choose of different thicknesses of reconstruction layer and the different ROI thicknesses on BMD values that were measured by QCT were analyzed. Results:The average BMD values of 1 mm and 5 mm thicknesses of reconstruction layer were respectively (117.41±45.97) mg/cm3 and (118.77±44.84) mg/cm3 when ROI thickness was 5 mm,with a statistically significant difference (t=-2.283,P<0.05). The average BMD values of 1 mm and 5 mm thicknesses of reconstruction layer were respectively (116.38±46.06) mg/cm3 and (119.06±44.55) mg/cm3 when the ROI thickness was 7mm,and the difference was statistically significant (t=-3.280,P<0.05). The average BMD values of 1 mm and 5 mm thicknesses of reconstruction layer were respectively (116.25±45.36) mg/cm3 and (120.12±44.10) mg/cm3 when the ROI thickness was 9 mm,and the difference was statistically significant (t=-5.841,P<0.001). The differences in BMD measurement values among 5,7 and 9 mm ROI thicknesses were not statistically significant when the thicknesses of reconstruction layer were respectively 1 and 5 mm. Conclusion:There is an effect of the thickness of QCT reconstruction layer on average BMD measurement values,and 1 mm thickness of reconstruction layer is more suitable to clinical application,while there is not significant effect in ROI thickness on average BMD measurement value of QCT. In clinical application,it is feasible to adjust ROI thickness according to actual situation so as to avoid the effect caused by some factors such as fracture or vertebral implants.

Objective To observe the correlations of artificial intelligence(AI)measured parameters on anteroposterior and lateral spinal X-ray films with the severity of adolescent idiopathic scoliosis(AIS).Methods Totally 1 786 AIS patients were retrospectively enrolled.Parameters including Cobb angle(CA),coronal balance distance(CBD),T1 slope(T1S),pelvic tilt(PT),sacral slope(SS),apical vertebral translation(AVT),thoracic trunk shift(TTS),thoracic kyphosis(TK)and sagittal vertical axis(SVA)on anteroposterior and lateral spinal X-ray films were measured using uAI DR scoliosis analysis system.The severity of AIS was evaluated according to CA,and the correlations between other parameters and the severity of AIS were explored.The above parameters were compared under different severity levels and coronal/sagittal equilibrium states.Multivariate logistic regression analysis was performed to screen the independent impact factors on the severity of AIS.Results Significant differences of the above parameters were found among different severity levels except for SVA(all P＜0.001).With the aggravation of AIS,CA,CBD,AVT and TTS increased successively(all P＜0.001).T1S of severe AIS was higher than that of mild and moderate AIS(both P＜0.001),PT and SS of moderate and severe AIS were all bigger,while their TK were smaller than those of mild AIS(all P＜0.001).Significant differences of CA,T1S,PT,SS,AVT,TTS and TK were found between coronal balanced and imbalanced AIS(all P＜0.05),while of TK were found between sagittal balanced and unbalanced AIS(P=0.026).CBD,T1S,PT,SS,AVT and TTS were all positively correlated(r,=0.136-0.606,all P＜0.001),while TK was negatively correlated(r,=—0.404,P＜0.001)with the severity of AIS.T1S,AVT and TTS were all independent impact factors of the severity of AIS(all P＜0.001).Conclusion Among AI measured parameters on anteroposterior and lateral spinal X-ray films,CBD,T1S,PT,SS,AVT and TTS were positively correlated,while TK was negatively correlated with the severity of AIS.

Objective:To assess the effect of using different thicknesses of reconstruction layer and different thicknesses of region of interest (ROI) on the results of vertebral bone mineral density (BMD) values that were measured by quantitative computed tomography (QCT). Methods:A total of 100 patients who underwent QCT screening for opportunistic osteoporosis between May and September 2021 at the First Affiliated Hospital of Zhengzhou University were retrospectively collected. Images that the thicknesses of QCT reconstruction layer were respectively 1 and 5 mm were transferred to the QCT Pro workstation,and ROI thicknesses were adjusted to 5,7,and 9 mm,respectively. The average BMD values of QCT measurements were recorded under different thicknesses of reconstruction layer and different ROI thicknesses. Then,the effects of the choose of different thicknesses of reconstruction layer and the different ROI thicknesses on BMD values that were measured by QCT were analyzed. Results:The average BMD values of 1 mm and 5 mm thicknesses of reconstruction layer were respectively (117.41±45.97) mg/cm3 and (118.77±44.84) mg/cm3 when ROI thickness was 5 mm,with a statistically significant difference (t=-2.283,P<0.05). The average BMD values of 1 mm and 5 mm thicknesses of reconstruction layer were respectively (116.38±46.06) mg/cm3 and (119.06±44.55) mg/cm3 when the ROI thickness was 7mm,and the difference was statistically significant (t=-3.280,P<0.05). The average BMD values of 1 mm and 5 mm thicknesses of reconstruction layer were respectively (116.25±45.36) mg/cm3 and (120.12±44.10) mg/cm3 when the ROI thickness was 9 mm,and the difference was statistically significant (t=-5.841,P<0.001). The differences in BMD measurement values among 5,7 and 9 mm ROI thicknesses were not statistically significant when the thicknesses of reconstruction layer were respectively 1 and 5 mm. Conclusion:There is an effect of the thickness of QCT reconstruction layer on average BMD measurement values,and 1 mm thickness of reconstruction layer is more suitable to clinical application,while there is not significant effect in ROI thickness on average BMD measurement value of QCT. In clinical application,it is feasible to adjust ROI thickness according to actual situation so as to avoid the effect caused by some factors such as fracture or vertebral implants.

Objective To observe the correlations of artificial intelligence(AI)measured parameters on anteroposterior and lateral spinal X-ray films with the severity of adolescent idiopathic scoliosis(AIS).Methods Totally 1 786 AIS patients were retrospectively enrolled.Parameters including Cobb angle(CA),coronal balance distance(CBD),T1 slope(T1S),pelvic tilt(PT),sacral slope(SS),apical vertebral translation(AVT),thoracic trunk shift(TTS),thoracic kyphosis(TK)and sagittal vertical axis(SVA)on anteroposterior and lateral spinal X-ray films were measured using uAI DR scoliosis analysis system.The severity of AIS was evaluated according to CA,and the correlations between other parameters and the severity of AIS were explored.The above parameters were compared under different severity levels and coronal/sagittal equilibrium states.Multivariate logistic regression analysis was performed to screen the independent impact factors on the severity of AIS.Results Significant differences of the above parameters were found among different severity levels except for SVA(all P＜0.001).With the aggravation of AIS,CA,CBD,AVT and TTS increased successively(all P＜0.001).T1S of severe AIS was higher than that of mild and moderate AIS(both P＜0.001),PT and SS of moderate and severe AIS were all bigger,while their TK were smaller than those of mild AIS(all P＜0.001).Significant differences of CA,T1S,PT,SS,AVT,TTS and TK were found between coronal balanced and imbalanced AIS(all P＜0.05),while of TK were found between sagittal balanced and unbalanced AIS(P=0.026).CBD,T1S,PT,SS,AVT and TTS were all positively correlated(r,=0.136-0.606,all P＜0.001),while TK was negatively correlated(r,=—0.404,P＜0.001)with the severity of AIS.T1S,AVT and TTS were all independent impact factors of the severity of AIS(all P＜0.001).Conclusion Among AI measured parameters on anteroposterior and lateral spinal X-ray films,CBD,T1S,PT,SS,AVT and TTS were positively correlated,while TK was negatively correlated with the severity of AIS.

Objective To systematically review the risk prediction models for postoperative pancreatic fistula(POPF)after pancreaticoduodenectomy(PD),and to provide a reference for the clinical screening and application of POPF-related risk models.Methods This study was conducted according to the PRISMA guidelines,with a PROSPERO registration number of CRD42023437672.PubMed,Scopus,Embase,Web of Science,the Cochrane Library,CNKI,VIP,Wanfang Data,China Medical Journal Full-text Database,and CBM were searched for studies on establishing risk prediction models for POPF after PD published up to April 26,2024.The PROBAST tool was used to assess the quality of articles,and RevMan 5.4 and MedCalc were used to perform the Meta-analysis.Results A total of 36 studies were included,involving 20 119 in total,and the incidence rate of POPF after PD was 7.4%—47.8%.A total of 55 risk prediction models were established in the 36 articles,with an area under the receiver operating characteristic curve(AUC)of 0.690-0.952,among which 52 models had an AUC of>0.7.The quality assessment of the articles showed high risk of bias and good applicability.MedCalc was used to perform a statistical analysis of AUC values,and the results showed a pooled AUC of 0.833(95%confidence interval:0.808-0.857).The Meta-analysis showed that body mass index,amylase in drainage fluid on the first day after surgery,preoperative serum albumin,pancreatic duct diameter,pancreatic texture,fat score,tumor location,blood loss,sex,time of operation,main pancreatic duct index,and pancreatic CT value were predictive factors for POPF(all P<0.05).Conclusion The risk prediction models for POPF after PD is still in the exploratory stage.There is a lack of calibration methods and internal validation for most prediction models,and only the univariate analysis is used to for the screening of variables,which leads to the high risk of bias.In the future,it is necessary to improve the methods for model establishment,so as to develop risk prediction models with a higher prediction accuracy.

Objective To evaluate the correlation and consistency between an artificial intelligence(AI)bone mineral density(BMD)measurement system based on 3D-Densenet neural network technology and quantitative computed tomography(QCT)in measuring BMD,as well as to assess its effectiveness in diagnosing osteoporosis(OP).Methods A total of 1 201 participants who underwent low dose computed tomography(LDCT)were retrospectively included.The AI BMD measurement system and QCT were utilized to measure the BMD of T12,L1,L2 vertebrae,and the average BMD.Consistency and correlation of BMD measurements between the two methods were assessed using Bland-Altman,Pearson,and Kappa analyses.With QCT results as the reference standard,the receiver operating characteristic(ROC)curve was drawn to evaluate the accuracy of AI BMD measurement system in diagnosing OP.Results The r and r2 for the average BMD measured by the two methods were 0.997 and 0.993,respectively.The Kappa value for the diagnosis of normal BMD,low bone mass,and OP using the AI BMD measurement system was 0.905.The area under the curve(AUC)for diagnosing OP using the AI BMD measurement system was 0.998,with a sensitivity of 0.888 and specificity of 0.997.Conclusion The AI BMD measurement system based on 3D-Densenet neural network technology has a high correlation and consistency with the QCT measurement result,which can accurately diagnose normal BMD,low bone mass,and OP.

Objective:To investigate the expression profile of IL-36 family members in patients with coronary atherosclerotic heart disease (CAHD) and to assess the regulatory effects of exogenous IL-36 on CD8 + T cell function in CAHD patients. Methods:Twenty controls and 82 CAHD patients including 31 with stable angina pectoris (SAP), 27 with unstable angina pectoris (UAP) and 24 with acute myocardial infarction (AMI) were enrolled in this study. Anti-coagulant peripheral blood samples were collected. Plasma and peripheral blood mononuclear cells were isolated. The levels of IL-36α, IL-36β, IL-36γ and IL-36 receptor antagonist (IL-36RA) in plasma were measured by ELISA. CD8 + T cells were enriched. The expression of IL-36 receptor subunits at mRNA level was semi-quantified by real time PCR. Flow cytometry was used to detect the expression of programmed death-1 (PD-1), cytotoxic T lymphocytes associated protein-4(CTLA-4) and lymphocyte-activation gene-3 (LAG-3) in CD8 + T cells. Levels of periforin, granzyme B, granulysin, IFN-γ and TNF-α in the culture supernatants of CD8 + T cells were measured by ELISA. Purified CD8 + T cells from controls and AMI patients were stimulated with recombinant human IL-36RA. Changes in the expression of immune checkpoint molecules and the secretion of cytotoxic molecules and cytokines after IL-36RA stimulation were analyzed. One-way analysis of variance or paired t-test was used for statistical analysis. Results:There were no significant differences in plasma IL-36α, IL-36β or IL-36γ level between the control, SAP, UAP and AMI groups ( P>0.05). Plasma IL-36RA level was significantly down-regulated in the AMI group as compared with that in the control, SAP and UAP groups[(1 159.57±297.83) pg/ml vs (1 773.47±754.29) pg/ml, (1 600.12±740.48) pg/ml and (1 578.72±720.42) pg/ml; P<0.05]. The expression of IL-1 receptor 6 (IL-1R6) and IL-1 receptor accessory protein (IL-1RAcP) at mRNA level, the expression of PD-1 and CTLA-4, and the secretion of IFN-γ and TNF-α by CD8 + T cells showed no significant differences between the four groups ( P>0.05). Periforin, granzyme B and granulysin levels secreted by CD8 + T cells of the AMI group were significantly higherthan those of the control, SAP and UAP groups ( P<0.05). In the control group, recombinant human IL-36RA stimulation did not affect the expression of immune checkpoint molecule or the secretion of cytotoxic molecules and cytokines by CD8 + T cells ( P>0.05). In the AMI group, the percentage of PD-1 + CD8 + T cells increased after recombinant human IL-36RA stimulation ( P=0.033), but no significant change in the percentage of CTLA-4 + CD8 + T cells was observed ( P=0.288). Moreover, recombinant human IL-36RA stimulation suppressed the CD8 + T cells of AMI patients to secrete periforin, granzyme B and granulysin ( P<0.05), but not affect the secretion of IFN-γ and TNF-α ( P>0.05). Conclusions:The reduced IL-36RA level in AMI patients might induce the enhancement of CD8 + T cell activity by promoting CD8 + T cells to secrete cytotoxic molecules, which was involved in the immunopathogenesis of AMI.

Objective: To investigate the clinical significance and pathological features of lymphocytes and plasma cells infiltration and related ectopic lymphoid-like structures in IgG4-related tubulointerstitial nephritis (IgG4-TIN). Methods: Complete data was collected from 24 patients with IgG4-TIN confirmed by pathology in the Peking University First Hospital. The renal specimens were examined by routine light microscopy, immunofluorescence and electron microscopy examination. In addition, immunohistochemistry was used to detect the distribution of CD20⁺ B lymphocytes, CD3⁺ T lymphocytes and CD138⁺ plasma cells. Results: A total of 24 patients were enrolled in the study, including 21 males (87.5%), 3 females (12.5%). The age was (58.0±10.8) years (38-75 years). Pathology analysis showed ectopic lymphoid-like structures were located in 16 (66.7%) cases and Russell bodies were detected in infiltrative plasma cells of 19(79.2%) cases with IgG4-TIN. Compared with cases without Russell body formation, cases with Russell body formation in renal interstitial plasma cells were more prone to show ectopic germinal center-like structure formation (P=0.001), tubular basement membrane (TBM) electron dense deposits (P=0.040) and reduced blood C3 levels (P=0.028). Conclusions Abnormal tubulointerstitial infiltration of ectopic lymphoid-like structures and plasma cells with prominent Russell body exist in IgG4-TIN patients, which suggests the persistent activation of lymphocytes and plasma cells in renal interstitium may contribute to the pathogenesis of IgG4-TIN.