【Abstract】 Objective To study the effects of ischemic preconditioning (IP) on the activity of nuclear factor-κB （NF-κB） and the expressions of TNF-α and intercellular adhesion molecule-1 (ICAM-1) during early reperfusion following liver transplantation in rats. Methods The models of rat orthotopic liver transplantation were established. The donor livers were stored for 2 hours in Ringers solution at 4 ℃ before transplantation. All rats were randomly divided into sham operation group （SO group）， control group and IP group. IP group was achieved by clamping the portal vein and hepatic artery of donor liver for 10 minutes followed by reperfusion for 10 minutes before harvesting. The activity of NF-κB and expressions of TNF-α and ICAM-1 at 1 h, 2 h, 4 h and 6 h after reperfusion were measured. Serum ALT, LDH were also determined. Results The liver function of recipients with IP were significantly improved. Compared with SO group， the graft NF-κB activity increased after transplantation in control group and IP group (P＜0.05), while compared with control group that was significantly attenuated at 1 h and 2 h in IP group. Similarly, hepatic levels of TNF-α and ICAM-1 were significantly elevated in control group and were reduced in IP group. Conclusion IP might down-regulated TNF-α and ICAM-1 expression in the grafts after orthotopic liver transplantation through depressed NF-κB activation， and attenuate neutrophil infiltration in the grafts after reperfusion.
This article aims to compare and analyze the biomechanical differences between wing-shaped titanium plates and traditional titanium plates in fixing acetabular anterior column and posterior hemi-transverse (ACPHT) fracture under multiple working conditions using the finite element method. Firstly, four sets of internal fixation models for acetabular ACPHT fractures were established, and the hip joint stress under standing, sitting, forward extension, and abduction conditions was calculated through analysis software. Then, the stress of screws and titanium plates, as well as the stress and displacement of the fracture end face, were analyzed. Research has found that when using wing-shaped titanium plates to fix acetabular ACPHT fractures, the peak stress of screws decreases under all working conditions, while the peak stress of wing-shaped titanium plates decreases under standing and sitting conditions and increases under forward and outward extension conditions. The relative displacement and mean stress of the fracture end face decrease under all working conditions, but the values are higher under forward and outward extension conditions. Wing-shaped titanium plates can reduce the probability of screw fatigue failure when fixing acetabular ACPHT fractures and can bear greater loads under forward and outward extension conditions, improving the mechanical stability of the pelvis. Moreover, the stress on the fracture end surface is more conducive to stimulating fracture healing and promoting bone tissue growth. However, premature forward and outward extension rehabilitation exercises should not be performed.
ObjectiveTo summarize recent researches on mechanism of the hepatic ischemic preconditioning (IPC) and its clinical applications on hepatectomy and liver transplantation. MethodsRelevant references about basic and clinical researches of hepatic IPC were collected and reviewed. ResultsRecent experimental researches indicated that IPC could relieve hepatic ischemiareperfusion injury (IRI) by remaining and improving energy metabolism of liver, regulating microcirculation disorder, decreasing the production of lipid peroxidation and oxyradical. It could also inhibit the activation of inflammatory cells and the release of cytokine, suppress cell apoptosis and induce the release of endogenous protective substance. Till now, most of the clinical researches had confirmed the protective function of hepatic IPC, but there were still some references with opposite opinions. ConclusionHepatic IPC could relieve liver IRI, but its clinical application value on hepatectomy and liver transplantation still need more researches to prove.
Objective Explore the effect of remote ischemic preconditioning (RIPC) on preoperative heart rate variability in patients with heart valves. Methods From January 2022 to July 2022, screening was conducted among 118 patients based on inclusion/exclusion criteria. Fifty-eight patients were excluded, and 60 patients participated in this trial with informed consent and were randomly divided into a RIPC group (n=30) and a control group (n=30). Due to the cancellation of surgery, HRV data was missing. 7 patients in the control group were excluded, and 5 patients in the RIPC group were excluded, 23 patients in the final control group and 25 patients in the RIPC group were included in the analysis. Comparison of relevant indicators of heart rate variability (standard deviation of NN interval (SDNN), standard deviation of mean value of NN interval in every five minutes (SDANN), mean square root of difference between consecutive NN intervals (RMSSD), percentage of adjacent RR interval>50 ms (PNN50), low frequency component (LF), high frequency component (HF) and LF/HF) at 8 hours in the morning on the surgical day between two groups of patients. Results There was no statistical difference in baseline characteristics between the two groups, and there was no significant difference in heart rate variability 24 hours before intervention (P>0.05). After the intervention measures were taken, the comparison of the results of heart rate variability at 8 hours on the day of operation showed that SDNN and SDANN of patients in the RIPC group were higher than those in the control group, with statistical differences (P<0.05). Conclusion RIPC can stabilize the preoperative heart rate variability of patients undergoing cardiac valve surgery.
The existing retinal vessels segmentation algorithms have various problems that the end of main vessels are easy to break, and the central macula and the optic disc boundary are likely to be mistakenly segmented. To solve the above problems, a novel retinal vessels segmentation algorithm is proposed in this paper. The algorithm merged together vessels contour information and conditional generative adversarial nets. Firstly, non-uniform light removal and principal component analysis were used to process the fundus images. Therefore, it enhanced the contrast between the blood vessels and the background, and obtained the single-scale gray images with rich feature information. Secondly, the dense blocks integrated with the deep separable convolution with offset and squeeze-and-exception (SE) block were applied to the encoder and decoder to alleviate the gradient disappearance or explosion. Simultaneously, the network focused on the feature information of the learning target. Thirdly, the contour loss function was added to improve the identification ability of the blood vessels information and contour information of the network. Finally, experiments were carried out on the DRIVE and STARE datasets respectively. The value of area under the receiver operating characteristic reached 0.982 5 and 0.987 4, respectively, and the accuracy reached 0.967 7 and 0.975 6, respectively. Experimental results show that the algorithm can accurately distinguish contours and blood vessels, and reduce blood vessel rupture. The algorithm has certain application value in the diagnosis of clinical ophthalmic diseases.
OBJECTIVE To understand the biological activities of the nerve regeneration conditioned fluid (NRCF). METHODS Nerve regeneration chamber was made by using silicone tube bridging distal and proximal ends of severed SD rat’s sciatic nerve. The biological activities of the proteins in NRCF, which were separated by natural polyacrylamide gel electrophoresis (PAGE), were analysed by being cocultured with excised neonatal dorsal root ganglia (DRG). RESULTS Eight separated protein bands of NRCF were observed between 67-669 ku in molecular weight, and the protein bands between 232-440 ku showed b neurotrophic and chemotactic function. CONCLUSION NRCF has the promoting effects on nerve regeneration.
Objective To investigate the protective effect of ischemic preconditioning (IP) on ischemicreperfusion injury of rat liver graft. MethodsMale Sprague Dawley rats were used as donors and recipients of orthotopic liver transplantation,the period of cold preservation and anhepatic phase were 100 min and 25 min respectively.Sixtyfour rats were randomly divided into 2 groups (n=32),control group: donor livers were flushed through the portal veins with physiological saline solution containing heparin only before harvested; IP group: before donor livers were harvested,the portal veins and hepatic arteries of them were interrupted for 10 min,and reflow was initiated for another 10 min,then did as control group.One half of each group were used to investigate 1 week survival rate of recipients,and another half of each group were used to take sample of blood and hepatic tissue after 2 hours of reperfusion of liver graft. ResultsOne week survival rate,amount of bile,serum NO and activity of antioxidase were higher in IP group than those in control group(P＜0.05),meanwhile,serum ALT,AST,LDH,TNF and superoxide in hepatic tissue were lower in IP group than those in control group (P＜0.05),and histological findings in IP group showed less injury than those in control group. Conclusion IP could increase production of serum NO,reduce the level of serum TNF and protect rat liver graft from ischemicreperfusion injury.
The three-dimensional (3D) liver and tumor segmentation of liver computed tomography (CT) has very important clinical value for assisting doctors in diagnosis and prognosis. This paper proposes a tumor 3D conditional generation confrontation segmentation network (T3scGAN) based on conditional generation confrontation network (cGAN), and at the same time, a coarse-to-fine 3D automatic segmentation framework is used to accurately segment liver and tumor area. This paper uses 130 cases in the 2017 Liver and Tumor Segmentation Challenge (LiTS) public data set to train, verify and test the T3scGAN model. Finally, the average Dice coefficients of the validation set and test set segmented in the 3D liver regions were 0.963 and 0.961, respectively, while the average Dice coefficients of the validation set and test set segmented in the 3D tumor regions were 0.819 and 0.796, respectively. Experimental results show that the proposed T3scGAN model can effectively segment the 3D liver and its tumor regions, so it can better assist doctors in the accurate diagnosis and treatment of liver cancer.
Objective To study the clinical significance of total gastrectomy in treatment for gastric cardia cancer.Methods The clinical data of 118 patients with gastric cardia cancer underwent operation from May 1997 to October 2012 in the Department of General Surgery of Baiyin Hospital， Affiliated to Lanzhou University were analyzed retrospe-ctively. Among these 118 patients， there were 65 patients treated by total gastrectomy （total gastrectomy group） and 53patients treated by proximal gastrectomy （proximal gastrectomy group）. The postoperative complications， survival rate，quality of life， and nutrition indexes were compared after operation between the total gastrectomy group and the prox-imal gastrectomy group. Results ① The incidence of postoperative complications was 7.7% （5/65） and 13.2% （7/53） in the total gastrectomy group and the proximal gastrectomy group， respectively， the difference was not statistically signi-ficant （χ2=0.972， P=0.248）. ② 1-， 3-， and 5-year survival rate after operation were 63.1%， 46.2%， and 30.8% in thetotal gastrectomy group；which were 66.0%， 36.9%， and 18.5% in the proximal gastrectomy group. The difference of 1-year survival rate after operation was not statistically significant in two groups （χ2=0.193， P=0.402）， the 3- and the 5-year survival rates of the total gastrectong group were significantly higher than those of the proximal gastrectony group （χ2=4.508， P=0.022；χ2=30.271， P=0.000）. ③ The Spitzer quality of life score had no difference at the different timeafter operation in two groups （P＞0.05）. Compared with the proximal gastrectomy group， the points of heartburn， swallo-wing problem， appetite， and food intake on 12 months after operation in the total gastrectomy group were higher （P＜0.05）， the points of the other indexes had no significant differences （P＞0.05）. ④ The nutrition indexes after operationhad no differences at the different time after operation in two groups （P＞0.05）. Conclusions Total gastrectomy in treatment for gastric cardia cancer would not increase complications， also can improve 5-year survival for patients withⅠ-Ⅲ stage， and survival condition after operation is also much better than that of proximal gastrectomy.
ObjectiveTo explore the conditions of synovial derived mesenchymal stem cells (SMSCs) differentiating into the fibrocartilage cells by using the orthogonal experiment. MethodsThe synovium was harvested from 5 adult New Zealand white rabbits, and SMSCs were separated by adherence method. The flow cytometry and multidirectional differentiation method were used to identify the SMSCs. The conditions were found from the preliminary experiment and literature review. The missing test was carried out to screen the conditions and then 12 conditions were used for the orthogonal experiment, including transforming growth factor β1 (TGF-β1), bone morphogenic protein 2 (BMP-2), dexamethasone (DEX), proline, ascorbic acid (ASA), pyruvic acid, insulin+transferrin+selenious acid pre-mixed solution (ITS), bovin serum albumin (BSA), basic fibroblast growth factor (bFGF), intermittent hydraulic pressure (IHP), bone morphogenic protein 7 (BMP-7), and insulin-like growth factor (IGF). The L60 (212) orthogonal experiment was designed using the SPSS 18.0 with 2 level conditions and the cells were induced to differentiate on the small intestinal submucosa (SIS)-3D scaffold. The CD151+/CD44+ cells were detected with the flow cytometry and then the differentiation rate was recorded. The immumohistochemical staining, cellular morphology, toluidine blue staining, and semi-quantitative RT-PCR examination for the gene expressions of sex determining region Y (SRY) -box 9 gene (Sox9), aggrecan gene (AGN), collagen type I gene (Col I), collagen type Ⅱ gene (Col Ⅱ), collagen type IX gene (Col IX) were used for result confirmation. The differentiation rate was calculated as the product of CD151/CD44+ cells and cells with Col I high expression. The grow curve was detected with the DNA abundance using the PicoGreen Assay. The visual observation and the variances analysis among the variable were used to evaluate the result of the orthogonal experiment, 1 level interaction was considered. The q-test and the least significant difference (LDS) were used for the variance analysis with a type Ⅲ calibration model. The test criteria (α) was 0.05. ResultsThe cells were certified as SMSCs, the double-time of the cells was 28 hours. During the differentiation into the fibrocartilage, the volume of the SIS-3D scaffold enlarged double every 5 days. The scaffolds were positively stained by toluidine blue at 14 days. The visual observation showed that high levels of TGF-β1 and BMP-7 were optimum for the differentiation, and BMP-7 showed the interaction with BMP-2. The conditions of DEX, ASA, ITS, transferrin, bFGF showed decreasing promotional function by degrees, and the model showed the perfect relevance. P value was 0.000 according to the variance analysis. The intercept analysis showed different independent variables brought about variant contribution; the TGF-β1, ASA, bFGF, IGF, and BMP-7 were more remarkable, which were similar to the visual observation. ConclusionIn the process of the SMSCs differentiation into the fibrocartilage, the concentrations of TGF-β1, ASA, bFGF, and IGF reasonably can improve the conversion rate of the fibrocartilage cells. The accurate conditions of the regulatory factor should be explored further.