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 study the risk factors of venous thromboembolism(VTE)and the predictive value of the improved VTE score model to identify the risk of VTE in gynecological surgery patients.Methods:From Janu-ary 1,2020 to December 31,2022,41 patients with VTE after gynecological surgery were selected as the VTE group,and a total of 164 patients with adjacent gynecological surgeries during the same period were selected as the non-VTE group with a ratio of 1 :4.Univariate and multivariate Logistic regression analysis were used to ana-lyze the risk factors of VTE after gynecological surgery,and a modified VTE risk factor rapid assessment model(referred to as the improved VTE score model)was constructed.The receiver operating characteristic(ROC)curve was used to study the predictive value for VTE for in gynecological surgery,and compared with the Caprini score model(Caprini table for short).Results:①Multivatiate Logistic regression analysis showed that there were independent risk factors for postoperative VTE in gynecology surgery(OR＞1,P＜0.05),including age≥60 years,BMI≥28 kg/m2,malignant tumors,surgery time＞3 hours,history of thrombosis,and the increased D-di-mer difference before and after surgery.②The Area under Curve(AUC)of ROC was 0.963 in the improved VTE score model with a Youden index 81.10％,sensitivity 87.80％and specificity 93.29％.The AUC of the Caprini score model was 0.888 with Youden index 63.41％,sensitivity 73.17％and specificity 90.24％.The improved VTE score model the Caprini score model identified 92.68％and 85.37％of VTE patients as high-risk or ex-tremely high-risk,respectively,but the difference was not statistically significant(P＜0.05).Conclusions:More attention should be paid to the six independent risk factors for postoperative VTE in gynecology surgery.The two score models showed a similar identified level.However,the improved VTE score model is more simple and easier to operate,has better practicality,and has certain clinical promotion value.

Background: Xylazole (Xyl) is a veterinary anesthetic that is structurally and functionally similar to xylazine. However, the effects of Xyl in vitro remain unknown. Objectives: This study aimed to investigate the anesthetic mechanism of Xyl using fetal rat nerve cells treated with Xyl. Methods: Fetal rat nerve cells cultured for seven days were treated with 10, 20, 30, and 40 μg/ mL Xyl for 0, 5, 10, 15, 20, 25, 30, 45, 60, 90, and 120 min. Variations of amino acid neurotransmitters (AANTs), Nitric oxide-Cyclic GMP (NO-cGMP) signaling pathway, and ATPase were evaluated. Results: Xyl decreased the levels of cGMP and NO in nerve cells. Furthermore, Xyl affected the AANT content and Na+ -K+ -ATPase and Ca2+ -Mg2+ -ATPase activity in nerve cells. These findings suggested that Xyl inhibited the NO-cGMP signaling pathway in nerve cells in vitro. Conclusions This study provided new evidence that the anesthetic and analgesic effects of Xyl are related to the inhibition of the NO-cGMP signaling pathway.

Objective:To explore the clinical characteristics, outcomes and influencing factors of influenza A virus-induced pneumonia in renal allograft recipients.Methods:During the 2015-2019 influenza season, 21 patients with influenza A virus-induced pneumonia after renal transplantation(RT)were prospectively recruited with 42 matched non-immunocompromised inpatients with influenza A virus-induced pneumonia.Clinical data, outcomes and follow-up observations after discharge were collected for analyzing the clinical characteristics of influenza A virus-induced pneumonia after RT.Continuous variables were compared by t-test or Mann-Whitney U test.And categorical variables were compared by Chi-Square test.Results:The median time after RT was 5(0.88, 10.50)years for RT recipients.In RT group, none received seasonal influenza vaccination with a vaccination rate of zero.The influenza vaccination rate of non-immunocompromised patients in current season was 42.86%(18/42)and inter-group difference was statistically significant( P<0.001). The levels of hemoglobin, aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase in RT recipients were(108.47±22.39)g/L, 21.00(16.00, 46.50)U/L, 15.00(12.00, 21.00)U/L and 314.00(207.25, 374.00)U/L.And the values were lower than those of non-immunocompromised patients[(130.24±21.74)g/L, 48.50(36.00, 79.50)U/L, 32.00(20.00, 52.25)U/L and 466.00(227.00, 781.75)U/L]. The differences were statistically significant( P=0.001, P<0.001, P<0.001, P=0.005). The levels of blood urea nitrogen and serum creatinine were 8.27(6.69, 12.48)mmol/L and 130.30(94.15, 204.70)mmol/L versus 5.42(3.37, 7.65)mmol/L and 65.90(48.98, 82.13)mmol/L in non-immunocompromised patients.The differences were statistically significant(all P< 0.001). No significant differences existed in the levels of C-reactive protein and procalcitonin between RT recipients and non-immunocompromised patients( P=0.774 and 0.821). The level of ESR and oxygenation index at admission were 39.00(13.00, 53.00)mm/h and(306.95±90.97)in renal recipients and 18.00(11.50, 23.00)mm/h and(200.17±116.35)in non-immunocompromised patients.The differences were statistically significant( P=0.045 and 0.001). Imaging studies indicated that multiple lobar involvement was a major imaging feature in both renal recipients and non-immunocompromised patients.The probability of pulmonary consolidation was 33.33%(7/21)in renal recipients and it was lower than that in non-immunocompromised patients.And the probability of pleural effusion was 42.86%(9/21)and it was higher than control.The inter-group differences were statistically significant( P=0.020 & 0.024). Rate of mechanical ventilation, CRRT and mortality were 42.86%(9/21), 23.81%(5/21)and 28.57%(6/21). All of them were higher than non-immunocompromised patients[21.43%(9/42), 9.52%(4/42)and 9.52%(4/42)]. However, there was no significant inter-group difference( P=0.076, 0.252 & 0.113). The median score of CURB-65 was 1(0.5, 1). Conclusions:Renal damage is prominent in hospitalized patients with influenza A virus-induced pneumonia after RT.There are a high rate of mechanical ventilation and CRRT during hospitalization and a high mortality.The prognosis remains poor for hospitalized patients with influenza A virus-induced pneumonia after RT.No matter how serious their conditions are at admission, they need to be closely monitored and aggressively treated.

Objective:To evaluate the role of interleukin-6 (IL-6) and CD4 + T-lymphocytopenia in assessing the severity and prognosis of coronavirus disease 2019 (COVID-19). Methods:A prospective observational study was conducted. Forty-five patients with COVID-19 admitted to Henan Provincial People's Hospital from January 13 to March 13, 2020 were enrolled and divided into normal group (13 cases), severe group (20 cases), critically severe group (12 cases) according to the severity of the disease. A total of 15 healthy subjects receiving physical examinations during the same period were collected as the healthy control group. Clinical data were collected to compare the clinical characteristics, general test results, IL-6 and CD4 + T-lymphocytopenia levels of patients in different disease severity groups and healthy control group. The receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of each indicator for the severity of COVID-19. Multivariate Cox regression analysis was used to analyze the risk factors affecting the prognosis of COVID-19 patients, and Kaplan-Meier survival curve analysis was performed. Results:The age of the critically severe group was significantly higher than that of the severe and normal groups (years old: 66.91±17.01 vs. 59.35±18.07, 40.23±12.61, both P < 0.05), and the negative conversion time of the 2019 novel coronavirus (2019-nCoV) was significantly longer than that of the severe and normal groups (days: 19.00±10.66 vs. 18.00±7.18, 9.31±3.49, both P < 0.05). With the increase of the severity of disease, white blood cell count (WBC), C-reactive protein (CRP), calcitonin (PCT), total bilirubin (TBil), troponin I (TnI), IL-6, D-dimer and other indicators were significantly increased, while lymphocyte count (LYM), platelet count (PLT), CD4 +, CD8 +, oxygenation index (PaO 2/FiO 2) were significantly decreased (all P < 0.01). ROC curve showed that PaO 2/FiO 2, IL-6 and CD4 + had certain predictive value for disease severity of COVID-19, the area under the ROC curve (AUC) of them were 0.903, 0.871, 0.689, and the 95% confidence interval (95% CI) were 0.806-0.949, 0.769-0.974, 0.542-0.853; the best cut-off values were 196.00 mmHg (1 mmHg = 0.133 kPa), 6.02 ng/L, 355 cells/μL, respectively; the sensitivity were 73.3%, 99.3%, 73.3%, and the specificity were 96.6%, 62.1%, 65.5%, respectively. Multivariate Cox regression analysis showed that age, PaO 2/FiO 2, high IL-6 and low CD4 + (IL-6≥6.02 ng/L and CD4 + < 355 cells/μL) were independent risk factors affecting the prognosis of COVID-19 [hazard ratio ( HR) was 1.077, 0.053 and 3.490, respectively, all P < 0.05]. Kaplan-Meier survival analysis showed that when both high IL-6 and low CD4 + (IL-6≥6.02 ng/L and CD4 + < 355 cells/μL) were present, the mean time of adverse prognosis was (20.53±5.71) days; when increased IL-6 and decreased CD4 + were inconsistent, the mean time of adverse prognosis was (53.21±3.16) days. Conclusions:The levels of IL-6 and CD4 + T-lymphocytopenia are closely related to the severity of COVID-19 disease. When IL-6 ≥ 6.02 ng/L and CD4 + < 355 cells/μL occur simultaneously, the prognosis is poor.