BACKGROUND:During the treatment of posterolateral tibial plateau fractures through the fibular head approach,the gap between the fibular head and the lateral plateau cannot accommodate the posterior placement of a plate for all patients.OBJECTIVE:To analyze,via finite element analysis,the differences in fixation strength resulting from varying the angles and quantities of horizontal arm variable angle screws in the plate during the treatment of posterolateral tibial plateau fractures through the fibular head approach.METHODS:A finite element model was established based on CT images of the knee to ankle joints of a 30-year-old healthy adult male volunteer.The models were divided into two categories:posteriorly placed group and non-posteriorly placed group based on whether the lateral locking compression plate was posteriorly placed.The posteriorly placed group was further subdivided into groups A-D based on the offset angle of the two variable angle screws(0°,5°,10°,and 15°).The non-posteriorly placed group was subdivided into groups E and F based on offset angles(0° and 15°).Finite element analysis was used to evaluate the von Mises stress distribution,maximum von Mises stress,and compressive displacement under loads of 250,500,and 750 N,exploring the mechanical differences between the groups.RESULTS AND CONCLUSION:(1)Finite element analysis results showed that under a 750 N load,the maximum compressive displacement trend of the internal fixation device was D＜B=C=F＜A＜E.The trend for maximum von Mises stress was B＜C＜A＜D＜F＜E.The trend for maximum compressive displacement on the bone was C=D＜B＜A＜F＜E,and for maximum von Mises stress,it was B＜C＜A＜F＜D＜E.The displacement and stress trends for the six models were similar under loads ranging from 250 N to 750 N.(2)These results suggest that for posterolateral tibial plateau fractures fixed through the fibular head approach,posterior placement of the plate should aim to accommodate two screws.If only one screw can be fixed during surgery,variable angle screws should be offset in the range of 0-15° to increase the probability of securing two screws.

Objective:To investigate the association between different types of lung nodules and the risk of lung cancer in a population at high risk of lung cancer and to provide an epidemiologic basis for the comprehensive management of lung nodules.Methods:Using the free lung cancer screening program of low-dose CT (LDCT) in Wenling, Zhejiang Province, we collected baseline and imaging information of high-risk groups for lung cancer who underwent LDCT screening from April 2019 to October 2021 and patients with previous history of lung cancer, tuberculosis, pneumoconiosis, and silicosis were excluded. A total of 28 539 study subjects were included in the analysis, and the follow-up ended on 31 December 2023. Based on the characteristics of the detected pulmonary nodules, the study subjects were classified with no nodules, with solid nodules, with pure ground glass nodules, and with part solid nodules groups. The association between different characteristics of lung nodules and the risk of lung cancer development was analyzed using the Cox proportional hazard regression model with a new diagnosis of lung cancer during the follow-up period as the outcome.Results:The overall detection rate of lung nodules with a mean diameter of ≥3 mm was 76.5%, of which 53.7%, 18.2%, and 4.6% were detected in the solid nodule, pure ground glass nodule, and partially solid nodule groups, respectively. There were statistically significant differences between the different nodule groups in terms of age, gender, BMI, history of toxic exposure education level, smoking status, history of lung disease, and family history of lung cancer (all P<0.05). The median follow-up time of the study population was 3.4 years, and 485 new lung cancer cases were diagnosed during the follow-up period. After adjusting for covariates, the results of multifactorial Cox proportional hazard regression model analysis showed that the risk of lung cancer was higher in pure ground glass nodules and part solid nodules compared with solid nodules, with HR values (95% CI) of 1.89 (1.52-2.35) and 6.49 (5.18-8.14), respectively. The results of subgroup analysis showed that patients in the group of part solid nodules had the highest risk of lung cancer in all strata of the population, followed by patients with pure ground glass nodules. Patients in the solid nodule group who were older or had previous lung disease had a higher risk of lung cancer, and the risk of lung cancer in the part solid nodule group differed between genders. Conclusions:The proportion of lung nodules detected is high in the high-risk group of lung cancer, and among them, patients with pure ground glass and part solid nodules have a higher risk of developing lung cancer. Attention should be paid to the annual follow-up management for patients with solid nodules who are older or who have had lung diseases, as well as for female patients with part solid nodules.

Objective:To investigate the association between different types of lung nodules and the risk of lung cancer in a population at high risk of lung cancer and to provide an epidemiologic basis for the comprehensive management of lung nodules.Methods:Using the free lung cancer screening program of low-dose CT (LDCT) in Wenling, Zhejiang Province, we collected baseline and imaging information of high-risk groups for lung cancer who underwent LDCT screening from April 2019 to October 2021 and patients with previous history of lung cancer, tuberculosis, pneumoconiosis, and silicosis were excluded. A total of 28 539 study subjects were included in the analysis, and the follow-up ended on 31 December 2023. Based on the characteristics of the detected pulmonary nodules, the study subjects were classified with no nodules, with solid nodules, with pure ground glass nodules, and with part solid nodules groups. The association between different characteristics of lung nodules and the risk of lung cancer development was analyzed using the Cox proportional hazard regression model with a new diagnosis of lung cancer during the follow-up period as the outcome.Results:The overall detection rate of lung nodules with a mean diameter of ≥3 mm was 76.5%, of which 53.7%, 18.2%, and 4.6% were detected in the solid nodule, pure ground glass nodule, and partially solid nodule groups, respectively. There were statistically significant differences between the different nodule groups in terms of age, gender, BMI, history of toxic exposure education level, smoking status, history of lung disease, and family history of lung cancer (all P<0.05). The median follow-up time of the study population was 3.4 years, and 485 new lung cancer cases were diagnosed during the follow-up period. After adjusting for covariates, the results of multifactorial Cox proportional hazard regression model analysis showed that the risk of lung cancer was higher in pure ground glass nodules and part solid nodules compared with solid nodules, with HR values (95% CI) of 1.89 (1.52-2.35) and 6.49 (5.18-8.14), respectively. The results of subgroup analysis showed that patients in the group of part solid nodules had the highest risk of lung cancer in all strata of the population, followed by patients with pure ground glass nodules. Patients in the solid nodule group who were older or had previous lung disease had a higher risk of lung cancer, and the risk of lung cancer in the part solid nodule group differed between genders. Conclusions:The proportion of lung nodules detected is high in the high-risk group of lung cancer, and among them, patients with pure ground glass and part solid nodules have a higher risk of developing lung cancer. Attention should be paid to the annual follow-up management for patients with solid nodules who are older or who have had lung diseases, as well as for female patients with part solid nodules.

BACKGROUND:During the treatment of posterolateral tibial plateau fractures through the fibular head approach,the gap between the fibular head and the lateral plateau cannot accommodate the posterior placement of a plate for all patients.OBJECTIVE:To analyze,via finite element analysis,the differences in fixation strength resulting from varying the angles and quantities of horizontal arm variable angle screws in the plate during the treatment of posterolateral tibial plateau fractures through the fibular head approach.METHODS:A finite element model was established based on CT images of the knee to ankle joints of a 30-year-old healthy adult male volunteer.The models were divided into two categories:posteriorly placed group and non-posteriorly placed group based on whether the lateral locking compression plate was posteriorly placed.The posteriorly placed group was further subdivided into groups A-D based on the offset angle of the two variable angle screws(0°,5°,10°,and 15°).The non-posteriorly placed group was subdivided into groups E and F based on offset angles(0° and 15°).Finite element analysis was used to evaluate the von Mises stress distribution,maximum von Mises stress,and compressive displacement under loads of 250,500,and 750 N,exploring the mechanical differences between the groups.RESULTS AND CONCLUSION:(1)Finite element analysis results showed that under a 750 N load,the maximum compressive displacement trend of the internal fixation device was D＜B=C=F＜A＜E.The trend for maximum von Mises stress was B＜C＜A＜D＜F＜E.The trend for maximum compressive displacement on the bone was C=D＜B＜A＜F＜E,and for maximum von Mises stress,it was B＜C＜A＜F＜D＜E.The displacement and stress trends for the six models were similar under loads ranging from 250 N to 750 N.(2)These results suggest that for posterolateral tibial plateau fractures fixed through the fibular head approach,posterior placement of the plate should aim to accommodate two screws.If only one screw can be fixed during surgery,variable angle screws should be offset in the range of 0-15° to increase the probability of securing two screws.

Objective:To investigate the role and mechanism of human umbilical cord mesenchymal stem cell exosomes (hUCMSC-ex) in wounds with escharectomy and skin grafting in scalded rats.Methods:The study was an experimental study. Twelve male Sprague-Dawley (SD) rats aged 6-8 weeks were divided into combined treatment group, fixed+allogeneic skin group, autologous skin+allogeneic skin group, and allogeneic skin group by random number table method (the same grouping method hereinafter), with 3 rats in each group. The four groups of rats were inflicted with scalded wounds on the back and performed with escharectomy, and then the wounds of rats in combined treatment group were fixed with a metal ring (the same fixing method hereinafter) and transplanted with autologous skin grafts and allogeneic skin grafts, and the other three groups of rats were fixed and/or transplanted with skin grafts corresponding to the group name. At 14, 21, and 28 d after surgery, the wound healing area in the four groups of rats was measured. Another 15 male SD rats aged 6-8 weeks were divided into normal group with no treatment, high exosome group, low exosome group, supernatant group, and phosphate buffer solution (PBS) group, with 3 rats in each group. The last 4 groups of rats were treated as that in the above-mentioned combined treatment group, and then were injected around the wounds with 200 μL of PBS containing 100 μg of hUCMSC-ex, 200 μL of PBS containing 50 μg of hUCMSC-ex, 200 μL of supernatant with no hUCMSC-ex, and 200 μL of PBS at 0 (immediately), 7, 14, and 21 d after surgery, respectively. At 14, 21, and 28 d after surgery, the wound healing area in the four groups of rats was measured. The wound neo-epithelial tissue of rats in high exosome group and PBS group at 28 d after surgery and the normal skin tissue of rats in normal group at the same time point were taken, and the differentially expressed proteins were screened by label-free quantitative proteomics method; the two up-regulated and differentially expressed proteins, the immunoglobulin G1 heavy chain constant region (IGHG1) and cystatin A (CSTA) with the largest and second largest fold changes in comparison between high exosome group and PBS group were selected, and their protein expressions were detected by Western blotting. The number of samples in all experiments was 3.Results:At 14, 21, and 28 d after surgery, the wound healing area in combined treatment group, autologous skin+allogeneic skin group, and allogeneic skin group of rats was significantly larger than that in fixed+allogeneic skin group ( P<0.05), the wound healing area in autologous skin+allogeneic skin group of rats at 21 d after surgery and that in allogeneic skin group of rats at 14 and 21 d after surgery was significantly larger than that in combined treatment group ( P<0.05), and the wound healing area in allogeneic skin group of rats at 14 d after surgery was significantly larger than that in autologous skin+allogeneic skin group ( P<0.05). The wound healing area of rats in high exosome group and low exosome group at 14, 21, and 28 d after surgery and in supernatant group at 14 and 28 d after surgery was significantly larger than that in PBS group ( P<0.05); the wound healing area in high exosome group of rats at 14 and 21 d after surgery was significantly larger than that in supernatant group ( P<0.05), and the wound healing area at 14 d after surgery was significantly larger than that in low exosome group ( P<0.05); the wound healing area in low exosome group of rats at 14 d after surgery was significantly larger than that in supernatant group ( P<0.05). Compared with that in PBS group, 332 proteins were differentially expressed in the neo-epithelial tissue of the wounds in high exosome group of rats at 28 d after surgery ( P<0.05), among which the protein expressions of IGHG1 and CSTA were significantly up-regulated (with fold change of 12.60 and 2.27, respectively, P<0.05). Compared with those of normal skin tissue in normal group, 1 400 and 1 057 proteins were differentially expressed in the neo-epithelial tissue of the wounds in high exosome group and PBS group of rats at 28 d after surgery, respectively. The protein expressions of IGHG1 and CSTA in the wound neo-epithelial tissue in high exosome group of rats at 28 d after surgery were significantly larger than those in normal skin tissue of rats in normal group ( P<0.05) and those in PBS group ( P<0.05). Conclusions:hUCMSC-ex may accelerate the repair process of wounds with escharectomy and skin grafting and improve the quality of wound healing in scalded rats by regulating the protein expressions of IGHG1 and CSTA.

Objective:To investigate the relationship between fat-to-muscle mass ration(FMR) and cognitive impairment in older adults with type 2 diabetes mellitus and to further explore the gender difference.Methods:A cross-sectional study was conducted on 768 elderly type 2 diabetes mellitus patients(≥60 years old) who were hospitalized in the Endocrinology Ward of Tianjin Union Medical Center from July 2018 to May 2022. The body composition was measured by bioelectrical impedance analysis(BIA), and the cognitive function was assessed using mini mental state examination(MMSE) and Montreal cognitive assessment(MoCA). According to the cognitive scale screening, type 2 diabetes mellitus patients were divided into normal cognitive function group and cognitive impairment group with stratified analysis by gender. New FMR indicators were developed based on BIA measurements, including fat mass(FM)/ appendicular skeletal muscle mass(ASM), FM/ skeletal muscle mass(SMM), and FM/ fat free mass(FFM). Binary logistic regression was used to analyze the relationship between FMRs and cognitive impairment risk, stratified by gender.Results:FMR indicators were not associated with cognitive impairment in females. In males, after adjusting for multiple factors, higher FMR values were significantly associated with an increased risk of cognitive impairment(FM/FFM: OR=1.722, 95% CI 1.230-2.409, P=0.002; FM/SMM: OR=1.337, 95% CI 1.118-1.599, P=0.001; FM/ASM: OR=1.240, 95% CI 1.077-1.427, P=0.003) and was independent of body mass index. For FM/FFM, every 0.1-unit increase raised the risk of cognitive impairment by 77.2%. FMR had a stronger association with cognitive impairment in the normal-weight group(body mass index<25 kg/m 2) than in the overweight/obese group(body mass index≥25 kg/m 2). The prevalence of cognitive impairment increased progressively with higher FMR . Conclusion:In men over 60 years with type 2 diabetes mellitus, FMR may be an independent risk factor for cognitive function.

Objective:To investigate the relationship between fat-to-muscle mass ration(FMR) and cognitive impairment in older adults with type 2 diabetes mellitus and to further explore the gender difference.Methods:A cross-sectional study was conducted on 768 elderly type 2 diabetes mellitus patients(≥60 years old) who were hospitalized in the Endocrinology Ward of Tianjin Union Medical Center from July 2018 to May 2022. The body composition was measured by bioelectrical impedance analysis(BIA), and the cognitive function was assessed using mini mental state examination(MMSE) and Montreal cognitive assessment(MoCA). According to the cognitive scale screening, type 2 diabetes mellitus patients were divided into normal cognitive function group and cognitive impairment group with stratified analysis by gender. New FMR indicators were developed based on BIA measurements, including fat mass(FM)/ appendicular skeletal muscle mass(ASM), FM/ skeletal muscle mass(SMM), and FM/ fat free mass(FFM). Binary logistic regression was used to analyze the relationship between FMRs and cognitive impairment risk, stratified by gender.Results:FMR indicators were not associated with cognitive impairment in females. In males, after adjusting for multiple factors, higher FMR values were significantly associated with an increased risk of cognitive impairment(FM/FFM: OR=1.722, 95% CI 1.230-2.409, P=0.002; FM/SMM: OR=1.337, 95% CI 1.118-1.599, P=0.001; FM/ASM: OR=1.240, 95% CI 1.077-1.427, P=0.003) and was independent of body mass index. For FM/FFM, every 0.1-unit increase raised the risk of cognitive impairment by 77.2%. FMR had a stronger association with cognitive impairment in the normal-weight group(body mass index<25 kg/m 2) than in the overweight/obese group(body mass index≥25 kg/m 2). The prevalence of cognitive impairment increased progressively with higher FMR . Conclusion:In men over 60 years with type 2 diabetes mellitus, FMR may be an independent risk factor for cognitive function.

OBJECTIVETo investigate the expression of acetyl coenzyme A synthetase short-chain family member 2 (ACSS2) in patients with colorectal cancer (CRC) and its biological role.

METHODSA total of 74 CRC tissue samples and 40 normal colorectal tissues were tested by immunohistochemical staining to detect the expression of ACSS2 (cell staining intensity score: 0 points: without staining, 1 points: weak staining, 2 points: intensity staining, 3 point: strong staining; the percentage of positive cells in tumor or negative score: 0 points: negative, 1 point: <25% positive cells, 2 points: 25%-50% positive cells, 3 points: 50%-75% positive cells, 4 points: >75% positive cells. The product of above two scores was the final score.). Association of ACSS2 expression with clinicopathological characteristics was analyzed. Small interfering RNA (siRNA, including A and B group) was used to knock down the expression of ACSS2 in colorectal cell lines (Lovo, HCT116) and their proliferation, migration and epithelial-mesenchymal transition (E-cadherin and Snail as markers) after knocking down were observed.

RESULTSThe expression of ACSS2 was significant higher in CRC tissue than that in normal colorectal tissue (tumor average score 6.284, normal tissue average score 3.625, P<0.01) and the percentage of positive cell was higher than that in normal tissue (tumor 69.9%, normal tissue 45.1%, P=0.000). The use of ACSS2 siRNA successfully knocked down the expression of ACSS2 in Lovo and HCT116 cells. A mild suppression of cell proliferation was observed 5 days after planked (A450 value: Lovo-NC 1.758±0.041, Lovo-ACSS2-siA 1.485±10.026, Lovo-ACSS2-siB 1.371±0.049; HCT116-NC 2.609±0.038, HCT116-ACSS2-siA 2.260±0.042, HCT116-ACSS2-siB 2.295±0.029). While a remarkable ability decline of cell migration was found (Lovo-NC 225±5/field, Lovo-ACSS2-siA 40±5/field, Lovo-ACSS2-siB 79±3/field; HCT116-NC 198±7/field, HCT116-ACSS2-siA 96±7/field, HCT116-ACSS2-siB 77±9/field, P<0.05). Real-time quantitative PCR detection showed that in Lovo cells, expression of E-cadherin up-regulated and expression of Snail down-regulated, while in HCT116 cells, E-cadherin up-regulated slightly [E-cadherin: Lovo NC 1.000±0.211, Lovo-siA 3.403±0.207, Lovo-siB 2.658±0.420 (P<0.05); HCT116 NC 1.000±0.121, HCT116-siA 1.349±0.197, HCT116-siB 1.528±0.147(P>0.05); Snail: Lovo NC 1.000±0.085, Lovo-siA 0.468±0.030, Lovo-siB 0.499±0.088 (P<0.05); HCT116 NC 1.000±0.118, HCT116-siA 0.265±0.020, HCT116-siB 0.194±0.017 (P<0.05)].

CONCLUSIONCRC tissues have high expression of ACSS2, which may be associated with cell migration and epithelial-mesenchymal transition.

Objective To explore the clinical value of the dual-low-dose with low tube voltage for head and neck CTA. Methods One hundred and sixty patients who were clinically suspected head and neck vascular disease underwent CTA procedure were propective selected, and whose body mass index (BMI) was also lower than 25 kg/m2. Forty cases were randomly selected as conventional group(120 kV,150 mAs, iodine 320 mg/ml), the other 120 cases were as the low dose group. The low dose group divided into three subgroups according to the random number table method, which were low iodine group (37 cases;120 kV,150 mAs, iodine 270 mg/ml), low tube voltage group (42 cases;100 kV,150 mAs, iodine 320 mg/ml) and low iodine and tube voltage group (41 cases;100 kV,150 mAs, iodine 270 mg/ml). The carotid bifurcated CT value, standard deviation (SD), signal-to-noise ratio (SNR), iodine intake and effective radiation dose (ED) of the four groups were recorded,all data undertook statistical analysis useing one-way ANOVA. Meanwhile, the subjective image quality score was applied to evaluate the image quality, and the differences among groups were compared by Wilcoxon signed ranks test. Results The image quality score were (2.85±0.19),(2.33 ± 0.34),(2.26 ± 0.32),(2.87 ± 0.22) in the four groups, and there was no statistical difference between groups(P>0.05).The carotid bifurcated CT value were respectively (380±30),(314±27),(514±52) and (425±28) HU in conventional, low iodine, low tube voltage and dual-low-dose groups, and the iodine intake were (18.85±2.10), (15.75±1.78), (18.53±1.98), (15.62±1.92) g, the ED of the four groups were (1.74±0.14), (1.73± 0.11), (1.32 ± 0.08) and (1.35 ± 0.09) mSv, the difference were all statistically significant (P<0.01). Furthermore, the iodine intake and the effective radiation dose in dual-low-dose group were significantly lower than the conventational group. Conclusions Head-and-neck CTA with dual-low-dose scan can provide same quality images as using 100 kV and high dose iodine contrast agent, and which also significantly reduced the ED and iodine intake greatly. Thus, this scanning program has great clinical value.