BACKGROUND:With social progress,the incidence rate of knee osteoarthritis is getting higher and higher in the face of the rapidly developing aging problem in the social population,and the number of total knee replacement operations is gradually increasing. OBJECTIVE:To study the relationship between prosthesis size and stress shielding by improving the tibial prosthesis base. METHODS:A female patient with severe knee osteoarthritis was selected.Based on Mimics,through extracting the bone structure of the knee joint and simulating the total knee replacement surgery,osteotomy,positioning,and implantation operations were carried out to establish the geometric modeling of the total knee replacement prosthesis(including the femoral prosthesis,tibial bracket,and tibial pad),and improve the design of the tibial prosthesis base,analyze the effect of different tibial prosthesis bases on stress shielding of surrounding bone tissue. RESULTS AND CONCLUSION:(1)Compared with single-stem tibial intramedullary stem prosthesis,the design of four-post tibial intramedullary stem prosthesis created a certain degree of stress shielding around the short stem.However,compared with a thicker single long stem,this stress shielding effect was significantly reduced,and the load was evenly distributed among the four short stems,so there was no stress concentration at the bottom of the pile.(2)The design with a rectangular hole in the middle not only provided relatively good stability,but also helped to reduce stress shielding of cancellous bone to a certain extent,with a reduction rate of 77.5%.(3)Compared with a single-stem tibial intramedullary stem prosthesis,both the four-post tibial intramedullary stem prosthesis and the four-post tibial intramedullary stem prosthesis with a hole in the middle have good stability,which can reduce stress shielding to a certain extent without causing stress concentration,providing theoretical guidance for the design of the tibial intramedullary stem.

Objective:To investigate the inhibitory effect of ferulic acid on the retina of diabetic mice and high glucose-induced human retinal pigment epithelium (RPE) cell injury and the mechanism.Methods:Thirty 8-week-old SPF male type 2 diabetic db/db mice were selected and divided into a model group and a ferulic acid group by the random number table method, with 15 mice in each group.Another 15 db/m mice of the same age were selected as a control group.The model and control groups received normal saline (5 ml/kg) by gavage daily, and the ferulic acid group received ferulic acid solution (0.05 g/kg) by gavage daily.After two months of treatment, the mice were sacrificed and the eyeballs were removed.The morphological changes of mouse retinal tissues were observed by hematoxylin-eosin staining.The fluorescence intensity and expression levels of mitochondrial calcium uniporter (MCU), p38 mitogen-activated protein kinase (p38 MAPK) and phosphorylated p38 MAPK (p-p38 MAPK) in mouse retinal tissues were detected by immunofluorescence staining and Western blot.Human RPE cells were divided into control group, dimethyl sulfoxide (DMSO) group, high glucose group and high glucose+ ferulic acid group.The control group received no treatment, and the other cell groups were cultured with the corresponding reagents for 24 hours.The reactive oxygen (ROS) level of RPE cells in each group was detected with the ROS detection kit.The mitochondrial membrane potential level of RPE cells was detected with the a mitochondrial membrane potential detection kit (JC-1).The MCU and microfilament fluorescence intensity of RPE cells were detected with the a microfilament green fluorescent probe.To explore the regulatory relationship between MCU, p38 MAPK and p-p38 MAPK, the MCU protein level was silenced and overexpressed by lentivirus transfection technology.The fluorescence intensity and expression levels of MCU, p38 MAPK and p-p38 MAPK proteins in RPE cells were detected by immunofluorescence staining and Western blot.The use and feeding of experimental animals followed the 3R principle and the Statement of the Association for Research in Vision and Ophthalmology on the Use of Animals in Ophthalmology and Vision Research.This study protocol was approved by the Ethics Committee of Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region (No.2019085).Results:The intercellular space of the outer nuclear layer, inner nuclear layer and ganglion cell layer of the retinal tissue in the model group was increased and the cell arrangement was disordered compared with the control group, and the retinal tissue in the ferulic acid group was significantly improved.Compared with the control group, the fluorescence intensity of MCU, p-p38 MAPK and MCU+ p-p38 MAPK protein of mouse retinal tissue in model group and ferulic acid group was significantly increased (all at P<0.05).Compared with the model group, the fluorescence intensity of MCU, p-p38 MAPK and MCU+ p-p38 MAPK protein of mice retinal tissue in ferulic acid group was significantly decreased (all at P<0.05).Compared with the control group, the relative expression levels of MCU, p38 MAPK and p-p38 MAPK proteins of mouse retinal tissue in model group were significantly increased (all at P<0.05).Compared with the model group, the relative expression levels of MCU, p38 MAPK and p-p38 MAPK proteins of mice retinal tissue in ferulic acid group were significantly decreased (all at P<0.05).The ROS fluorescence intensities in the control group, DMSO group, high glucose group and high glucose+ ferulic acid group were 0.22±0.02, 0.22±0.03, 0.30±0.02 and 0.24±0.02, respectively, and the overall difference was statistically significant ( F=7.845, P<0.01).The ROS fluorescence intensity was significantly higher in the high glucose group than in the control and DMSO groups, and it was significantly lower in the high glucose+ ferulic acid group than in the high glucose group (all at P<0.05).The mitochondrial membrane potential was significantly lower in high glucose group and high glucose+ ferulic acid group than in control and DMSO groups, and significantly higher in high glucose+ ferulic acid group than in high glucose group (all at P<0.05).Compared with the control group and DMSO group, the fluorescence intensity of MCU was higher in the high glucose group, accompanied by the decrease and thinning of cell microfilaments, and the fluorescence intensity of MCU protein was significantly decreased in high glucose+ ferulic acid group, with the number of microfilaments increased significantly.Compared with the control group and DMSO group, the fluorescence intensity and relative expressions of MCU, p38 MAPK and p-p38 MAPK proteins were significantly increased in the high glucose group (all at P<0.05).Compared with the high glucose group, the fluorescence intensity and relative expressions of MCU, p38 MAPK and p-p38 MAPK proteins were significantly decreased in the high glucose+ ferulic acid group (all at P<0.05).Compared with the control group and the empty vector group, the relative expressions of MCU, p38 MAPK and p-p38 MAPK proteins were significantly increased in the MCU overexpression group and significantly decreased in the MCU shRNA group and the MCU overexpression+ ferulic acid group (all at P<0.05).Compared with MCU overexpression group, the relative expressions of MCU, p38 MAPK and p-p38 MAPK proteins were significantly decreased in MCU shRNA group and MCU overexpression+ ferulic acid group, and the differences were statistically significant (all at P<0.05). Conclusions:Ferulic acid can regulate oxidative stress and mitochondrial dysfunction, thereby ameliorating retinal damage and high glucose-induced RPE cell injury in diabetic mice, which may play a protective role through MCU and p38MAPK signaling pathways.

Purpose To explore the clinical application value of dual-layer detector spectral CT combined with half volume contrast agent in detecting the liver metastases in portal vein phase.Materials and Methods Ninety-six patients with liver metastases diagnosed by liver enhanced CT in the First Affiliated Hospital of Fujian Medical University from November 2021 to June 2022 were prospectively studied.They were randomly divided into two groups by using the contrast agent administration calculation method based on body surface area.The conventional polyenergetic image(CI)of patients in the conventional contrast agent group(48 cases with 18.6 gI/m2 body surface area iodine contrast agent)was constructed in the portal vein phase,and the 40-70 keV(5 kiloelectron voltage)virtual monoenergetic imaging(VMI)was reconstructed for patients in the semi contrast agent dose group(48 case with 9.3 gI/m2 body surface area iodine contrast agent).The image noise,CT value and contrast noise ratio in the two groups were measured and compared.Besides,the image quality was scored with a 5-point method,and the consistency of subjective scores between two radiologists were evaluated.Results The VMI noise at 40-70 keV was(10.26±1.38)Hu,(9.59±1.35)Hu,(9.15±1.31)Hu,(8.80±1.32)Hu,(8.58±1.31)Hu,(8.40±1.31)Hu and(8.27±1.33)Hu;while the CI noise was(10.86±1.13)Hu.It revealed that the VMI noise at 45-70 keV was lower than the CI noise(t=-3.885,-5.343,-6.449,-7.180,-7.756 and-8.132,P<0.001).There was no significant difference between VMI and CI noises at 40 keV(t=-1.800,P>0.05).With the decrease of energy level,CT value of normal liver parenchyma,and contrast noise ratio values of liver parenchyma and liver metastases gradually increased,at the 40 keV level,the values of which were(148.31±21.34)Hu,8.81±2.83 and 8.18±2.85;at the 45 keV level,the values were(130.10±16.95)Hu,7.66±2.46 and 7.48±2.55;at the 50 keV level,the values were(116.19±13.55)Hu,6.60±2.08 and 55.40±13.77,reaching the highest at 40 keV level,while the CI values were(118.02±7.02)Hu,5.69±1.11 and 5.77±1.41.Therefore,the value of 40 keV and 45 keV VMI was significantly higher than CI(t=3.804,4.883,4.462,all P<0.05;t=2.854,3.465,3.378,all P<0.05),respectively.There was no significant difference between 50 keV VMI and CI(t=-0.612,1.739,2.208,P>0.05).The subjective score in the overall quality of VMI images was higher than that of CI at 40-50 keV(t=9.628,7.508,3.514,P<0.05).The subjective scores of the two physicians were good consistent among image contrast,image noise and overall image quality(Kappa=0.766,0.749 and 0.661,P<0.05),respectively.Conclusion VMI at 40-50 keV can provide better image quality and display ability of liver metastases than CI images at portal vein phase with a 50%reduction in contrast agent dose.

Objective:To investigate the predictive value of the quantitative parameters of dual-layer detector spectral CT in arterial and venous phases for the differentiation degree and the E-cadherin protein expression of gastric cancer.Methods:This was a cross-sectional study. The preoperative data from the dual-layer detector spectral CT images among 183 patients with gastric adenocarcinoma confirmed by operation and pathology was retrospectively analyzed from October 2021 to October 2022 in the First Affiliated Hospital of Fujian Medical University. According to the differentiation degree and E-cadherin protein expression of gastric cancer, all patients were divided into the moderately well differentiated group ( n=82) and the poorly differentiated group ( n=101), as well as the E-cadherin-negative group ( n=80) and the E-cadherin-positive group ( n=103). The CT images in arterial and venous phases were used to reconstruct the virtual monoenergetic images (VMI) at 40, 50, 60, 70, 80, 90, and 100 keV, effective atomic number (Z eff) images and iodine concentration (IC) images. The CT values (CT keV) from VMI, Z eff and IC were measured, and the normalized Z eff (NZ eff) and the normalized IC (NIC) were calculated. Independent-sample t test or Mann-Whitney U test were used to compare the differences in quantitative parameters between groups. The logistic regression analysis was used to screen for the independent predictors, after which a combined prediction model was constructed. The receiver operating characteristic curves were used to evaluate the predictive efficiency of the parameters for the differentiation degree and the E-cadherin protein expression of gastric cancer. Results:There were statistically significant differences in CT 40 keV to CT 70 keV, NZ eff and NIC in dual-phase, as well as Z eff and IC in the venous phase between the moderately well differentiated group and the poorly differentiated group ( P<0.05). The combined prediction model was constructed by CT 40 keV ( OR=1.03, 95% CI 1.02-1.05, P<0.001) in arterial phase and CT 40 keV ( OR=1.05, 95% CI 1.03-1.07, P<0.001) and Z eff ( OR=1.32, 95% CI 1.06-1.65, P=0.015) in venous phase, of which the area under the curve (AUC) for the prediction of the moderately-well group and the poor group was 0.932 (95% CI 0.897-0.967), with a sensitivity of 90.1% and a specificity of 85.4%. Between the E-cadherin-negative group and the E-cadherin-positive group, CT 40 keV and NZ eff in arterial phase, as well as CT 40 keV to CT 70 keV, Z eff, NZ eff, IC and NIC in venous phase, had statistically significant differences ( P<0.05). The AUC for the combined prediction model established by CT 40 keV ( OR=1.02, 95% CI 1.01-1.04, P<0.001) and Z eff ( OR=1.33, 95% CI 1.09-1.63, P=0.006) in venous phase was 0.800 (95% CI 0.736-0.864), with a sensitivity of 95.0% and a specificity of 60.2%. Conclusion:The combined prediction model from the quantitative parameters of dual-layer spectral detector CT can be used to predict the differentiation degree and the E-cadherin protein expression of gastric cancer preoperatively.

Objective:To explore the effect of abdominal massage on the behavior of rats with neonatal hypoxia-ischemia and its mechanism.Methods:7-day-old SD rats were made as the HIBD model by the classical method of RICE and then the HIBD model rats were divided into the abdominal massage group and model group according to the random number table method, with 12 rats in each group, and 12 rats were selected as the normal group. The abdominal massage group was given abdominal massage 24 hours after the modeling, and the intervention continued for 28 days. Rats in each group underwent a balance beam test on the 7th, 14th, 21st, and 28th day of the intervention. After the intervention, HE staining was applied to observe the morphological structure of the hippocampal CA1 region of the rats; Quantitative Real-time PCR method was used to measure the serotonin receptor (5-HTR1A) in the hippocampus. The expression of cAMP, PKA and CREB in the hippocampus were measured by immunohistochemistry, and the expression of SYP protein was measured by Western blotting.Results:After the intervention, the cells in the hippocampal CA1 area of the model group were diffusely distributed, the number of neurons reduced, and the condition of inflammatory edema appeared; the cells in hippocampal CA1 area of the abdominal massage group were arranged clearly, and the condition of inflammatory edema has significantly improved; on the 21st and 28th day of the intervention, the balance beam test scores in the abdominal massage group significantly decreased ( P<0.05), and the relative expression of 5-HTR1A mRNA (1.18±0.08 vs. 0.77±0.04) in the abdominal massage group significantly increased ( P<0.05). The expression of cAMP (0.32±0.02 vs. 0.31±0.01), PKA (0.32±0.02 vs. 0.29±0.01),CREB (0.31±0.02 vs. 0.28±0.01) and SYP in the abdominal massage group significantly increased ( P<0.05). Conclusion:Abdominal massage could improve the behavior of neonatal hypoxic-ischemic rats, which may play a role on nerve repair by regulating 5-HTR1A/cAMP/PKA signaling pathway.

Objective:To explore the value of diffusion tensor imaging (DTI) in evaluating the effects of hyperbaric oxygen therapy (HOT) in treating spinal cord injury.Methods:The modified Allen′s method was used to induce a traumatic spinal cord injury in 30 rats who were then divided randomly into an injured group and a treatment group, each of 15. The treatment group was given HOT twice a day for 3 days, then once a day for a total of 4 weeks. The injured group did not receive HOT. DTI was performed (along with Basso-Beattie-Bresnahan (BBB) evaluation) at 0h, 6h, 24h, as well as 3, 7, 14, 21 and 28 days after the operation. Two-factor repeated measures ANOVA was conducted to analyze any differences in the DTI results: the fractional anisotropy, mean apparent diffusivity, radial diffusivity and axial diffusivity, as well as the BBB scores. LSD t-tests were performed to analyze the significance of the differences at different time points.Results:At each time point after 24h the average FA value of the treatment group was significantly higher than the injured group′s average, while its average MD and RD values were significantly lower. Beyond 14 days the average AD value of the treatment group was significantly higher than that of the injured group. The treatment group′s average BBB score was also significantly higher at all the time points beyond 3 days.Conclusions:DTI results can evaluate spinal cord function and provide valuable information for the dynamic assessment of hyperbaric oxygen therapy after a traumatic spinal cord injury, and the therapy promotes the recovery of motor function, at least in rats.

Objective: To observe the influence of lower wide pedicle frontal periosteum flap on frontal bone absorption rate after cranioplasty. Methods: From February 2016 to July 2017, the lower wide pedicle frontal periosteum flap was produced in 12 patients of Shanghai Ninth People′s Hospital (7 males/5 females, aged 5-9 years, 10 hypertelorism, 2 Crouzon syndrome), who accepted intro-cranio-route plastic surgery, to cover the frontal bone window. A spiral CT scans were applied one week (t1) and one year (t2) after surgery. DICOM data was imported into Mimics software to reconstruct the 3D model of skull. The bone window covered the frontal bone was selected and the bone volume was calculated. The absorption rate was calculated as (Vt₁-Vt₂)/Vt₁×100%. As a control group, the CT data of 20 patients (from January 2010 to December 2015, 11 males/9 females, 7 hypertelorism, 12 Crouzon syndrome, 1 Pfeiffer syndrome) were analyzed retrospectively in the same way, and compared to the experimental group. Results: The average bone absorption rate in experimental group was 8.65%±2.56% (n=12), while in control group it was 26.51%±5.23% (n=20). Significant statistical difference was observed. No further cranial defect was observed in one-year follow-up in both two groups. Conclusions The lower wide pedicle frontal periosteum flap reduces the bone absorption rate after intro-cranio-route plastic surgery. It could also help to repair the anterior cranial base defect during the surgery. This technique was recommend as a regular step in craniofacial surgeries.

Objective To explore the value of DTI quantitative parameters in evaluating neurological function changes of acute traumatic spinal cord injury (TSCI)in rat models.Methods The modified Allen's dropping weight technique was used to establish TSCI rat models.Then the rats were divided into mild injury group,moderate injury group and severe injury group (each n=10).DTI examination and Basso-Beattie-Bresnahan (BBB) score were performed pre-TSCI and 0 h,6 h,24 h,3 day,7 day and 14 day post-TSCI,respectively.The BBB scores and DTI parameters,including FA,mean apparent diffusivity (MD),radial diffusivity (RD) and axial diffusivity (AD) were measured and compared among groups.The correlation between BBB scores and the parameters was evaluated.Results The differences of FA,MD and RD value were statistically significant among varying injury degree groups and different time points after TSCI (all P＜0.05).AD value had statistical difference among different time points (F=12.720,P＜0.001),whereas no difference was found among varying injury degree groups (F=0.469,P=0.630).FA and MD values decreased while RD increased 0 h post-TSCI.Then RD and MD increased continuously,whereas FA decreased continuously until 24 h post TSCI (all P＜0.05),and the parameters kept stable after 24 h post-TSCI (all P＞ 0.05).The BBB scores were lowest on 0 h post-TSCI,then maintained increasing (all P＜0.05).In addition,the BBB scores and MD values had good correlation (r=0.958,P＜ 0.01).Conclusion DTI can quantitatively evaluate function changes of TSCI in rat models.Moreover,treatment within 24 h post-TSCI might be recommended for TSCI therapy.

Objective To investigate the effect and the mechanism of parecoxib sodium pretreatment on permeability of blood-brain barrier in a rat model of focal cerebral ischemia-reperfusion injury.Methods Sixty male SD rats weighing 300g were randomly divided into 5 groups (n=12 each):sham operation group (group S);focal cerebral I/R group (group I/R);parecoxib sodium 5 mg/kg pretreatment group (group L);parecoxib sodium7.5mg/kg pretreatment group (group M);parecoxib sodium 10 mg/kg pretreatment group (group H) Middle cerebral artery occlusion models were made by reforming Longa suture method in SD rats.Thirty minutes before ischemia,rats in group L,M and H were injected with 5 mg/kg、7.5 mg/kg and 10 mg/kg parecoxib sodium through the internal jugular vein.Group S and group I/R received equal volume of normal saline.ELISA technique was used to determine the content of S100 β,TNF-α,IL-1 β in Plasma.The changes of cerebral water content and the Evans Blue exudation from brain capillaries were observed.Results Pretreated with parecoxib sodium (5mg/kg、7.5 mg/kg and 10 mg/kg),the content of S100 β,TNF-α,II-1 β in plasma were reduced.The cerebral water content and the EB in brain were reduced.Pretreated with parecoxib sodium 10 mg/kg,Longa scores were reduced.Conclusion Pretreatment with Parecoxib can protect blood-brain barrier against focal cerebral I/R injury by inhibition of the inflammatory reaetion.

Objective To analyze the popular characteristic and drug resistance of Pseudomonas aeruginosa in a hospital of Guiy-ang from January 201 1 to December 2013.Methods The distribution characteristic and drug resistance of Pseudomonas aeruginosa isolated from clinical samples from January 201 1 to December 2013 were analyzed retrospectively.Results A total of 642 strains of Pseudomonas aeruginosa were isolated for three years in our hospital from January 201 1 to December 2013,there was 57.0% isola-ted from sputum specimens,and 27.9% isolated from excreta of wound.The infected endemic area distribution was made up of Or-thopedic Surgery,ICU,Geriatrics Department and Respiratory Department accounting for 22.9%,20.1%,18.8% and 1 5.9% re-spectively.Pseudomonas aeruginosa was most sensitive to polymyxin bacillosporin.The drug resistance rates to Trimethoprim,Am-picillin and Cefazolin were all 100.0%.The drug resistance rates to Ampicillin/sulbactam and Ceftriaxone were 90.0%. Conclusion Pseudomonas aeruginosa is the main cause of lower respiratory tract infections in patients and wound infection and show serious multi-drug resistant,so it is necessary to use drugs reasonably according to the drug susceptibility results.