【摘要】 目的 探讨建立局部性家兔肠系膜静脉血栓（MVT）模型的方法。 方法 于2008年1月，将36只家兔随机均分为3组，肠系膜前静脉局部阻断加静脉分支注射凝血酶，A组80 U/mL，B组40 U/mL，C组注射生理盐水1 mL。观测血栓形成时间、范围和周围静脉血D-二聚体（DD）变化。 结果 A、B两组均可建立控制范围内稳定MVT模型，血栓形成时间分别为（15.6±2.0） min和（22.3±2.5）min，两组比较有统计学意义（Plt;0.001）；术前A、B两组DD为（68.4±5.7）ng/mL、（72.7±6.4）ng/mL，血栓形成后为（209.0±24.0）ng/mL、（215.4±17.6）ng/mL，组内比较有统计学意义（Plt;0.001）；C组不形成血栓。 结论 局部静脉阻断加凝血酶注射法可建立稳定和范围可控的MVT模型，建模前后血浆DD值有一定实验参考价值。【Abstract】 Objective To establish the model of local mesenteric venous thrombosis (MVT) in rabbits. Methods In January 2008, 36 rabbits were randomly divided into three groups with 12 rabbits in each. The anterior mesenteric veins were blocked regionally, and at the same time the rabbits were injected with thrombin 80 U/mL through the branches of mesenteric vein in group A, 40 U/mL in group B, and 1 mL normal saline in group C. Time and range of thrombosis were observed, and D-dimer level in peripheral vein was tested. Results Stable MVT model was established in intended region in both group A and B. There was a significant reduction of thrombosis time in group A [(15.6±2.0) minutes] when compared with that in group B [(22.3±2.5) minutes] (Plt;0.001). The levels of D-dimer in group A two hours after operation [(209.0±24.0) ng/mL] increased significantly compared with that before the operation [(68.4±5.7) ng/mL](Plt;0.001); while the same condition was found in group B [(215.4±17.6) ng/mL vs (72.7±6.4) ng/mL] (Plt;0.001). No thrombus was found in group C. Conclusion Stable MVT model with controllable thrombotic range can be established by regional vein blockade plus thrombin injection. Plasma D-dimer levels before and after model establishment could be as a parameter for assessing the experiment.
Objective To establish a reliable rats model of orthotopic liver transplantation with non-heart beating donors. Methods The model was established with modified double-cuff method. According to obtain pre-liver warm ischemia time experiencing non-heart-beat the rats were divided into 3 groups: 10 min (R10 group), 20 min (R20 group) and 30 min (R30 group), then one week survival after operation was compared in rats. Results The operative time of donor was 30 min approximately except warm ischemia time and the cold preservation time of donor liver was 1 h. The anastomotic time for suprahepatic vena cava was 12-22 min (mean 15 min). The anastomotic time for portal vein and infrahepatic vena cava was about 2 min and 1 min, respectively. The anhepatic phase sustained 14-24 min (mean 19 min). The operative time of receptor was 50-65 min (mean 60 min). Twelve rats died at 24 h after operation, which was considered as operative failure. The success rates of operation in R10 group, R20 group, and R30 group were 95% (19/20), 80% (16/20), and 65% (13/20), respectively. After one week the survival rate was 95% (18/19), 81% (13/16), and 54% (7/13), respectively. Conclusions Improved non-heart donor liver transplantation model of rat on the basis of Kamada’s “twocuff technique” acts as a good simulation in clinical non-heart-donor liver transplantation. This study showes that rat liver can tolerate warm ischemia time less than 30 min, the short-term survival after transplantation can reach satisfactory results. However, long-term survival requires further study.
目的 探讨主要组织相容性复合体(MHC)Ⅱ类基因的反式转录因子（CⅡTA）在多器官功能障碍综合征（MODS）中对MHCⅡ类基因的调控机理。方法 18只雄性家猪随机分为实验组（n=9）和对照组(n=9)。实验组给予失血性休克、再灌注损伤、内毒素血症等复合干扰因素，建立二次打击猪MODS模型； 对照组仅进行麻醉和动静脉插管。7 d后处死存活动物。切取实验组造模成功动物和对照组动物的脾脏组织，用Trizol法提取总RNA。设计CⅡTA和猪MHCⅡ类基因(SLA-DQA)引物序列，逆转录构建cDNA，行实时荧光定量PCR检测。UVP计算机图像分析系统绘出标准曲线并得出2组CⅡTA mRNA和SLA-DQA mRNA的拷贝数。以Pearson法分析MODS动物CⅡTA mRNA和SLA-DQA mRNA表达的相关性。结果 实验组动物死亡7例，有8例发生MODS。对照组动物CⅡTA mRNA的拷贝数为（3.516±1.237）×103，实验组MODS动物为（0.367±0.088）×103，差异有统计学意义（P=0.000）； 对照组SLA-DQA mRNA拷贝数为（5.330±3.053）×103，实验组为（1.376±1.006）×103，差异亦有统计学意义(P=0.002)。MODS动物中CⅡTA mRNA和SLA-DQA mRNA的表达呈正相关(Pearson值为0.499，P=0.017)。结论 MODS模型复制满意。MHCⅡ类基因在MODS中表达下降与CⅡTA的调控有关。
【Abstract】 Objective To establ ish a stable animal model for glucocorticoid-induced avascular necrosis of femoral head in rabbits. Methods Thirty-six adult New Zealand rabbits were randomly divided into four groups:ten were injected twice with l i popolysaccharide (group A), ten were treated with a combination of l i popolysaccharideand methylprednisolone (group B), ten were injected three times with methylprednisolone (group C), and six wereinjected normal sal ine as a control (group D). MR imaging was performed in the rabbits before the first injection ofl i popolysaccharide or methylprednisolone, and at 2, 4, and 6 weeks after the last injection of l i popolysaccharide ormethylprednisolone. Histopathological changes in the femoral heads were observed by l ight microscope and transmission electron microscope at the end of six weeks after the injection. Vascular infusion with Chinese ink was made to evaluate the morphological changes of blood vessels in the femoral head. The percentage of trabecular bone area and empty lacunae and microvascular density were measured. According to the histological and MR imaging appearance of the femoral heads in all groups, the incidence of osteonecrosis of every group was calculated. Results Listlessness, blepharal hyperemia,less activity and reduced diet were found in the rabbits of groups A and B after injected with l ipopolysaccharide. At 3 weeks after the final injection, the body weight of groups B and C was decreased. At 4 weeks after the final injection, the body weight of groups A and D was increased. No abnormal signal could be detected on MR images in rabbits of all groupsbefore injection and at 2 weeks after the injection. At 4 weeks and 6 weeks after the last injection, irregular low signal on T1-weighted images and irregular low or high signal on T2-weighted images could be detected on MR images in rabbits of groups B and C, no abnormal signal could be detected on MR images in rabbits of groups A and D. At 6 weeks after the last injection,the trabecular bone of group B became thin and sparse, some were broken. The percentages of empty lacunae were 11.8% ± 4.7%, 34.4% ± 6.2%, 20.0% ± 4.7% and 9.3% ± 4.6%; the percentages of trabecular bone area were 59.2% ± 6.8%, 40.1% ± 6.0%, 51.5% ± 5.6% and 63.2% ± 8.3%; and the microvascular densities were 14.3% ± 2.7%, 4.5% ± 2.1%, 10.2% ± 3.1% and 15.4% ± 4.1% in groups A, B, C and D respectively. There were statistically significant differences between group B and groups A, C, D (P lt;0.01). The fatty tamponade accumulated in the medullary cavity and intramedullary vascular sinusoids were pressed by the l ipocytes and became narrow. Limposomes were found in osteocytes and vascular endothel ia of group B and group C. Osteocytes of group B crimpled and pyknosis or karyolysis of chromatin were observed in these osteocytes, nuclearmembrane of the osteocytes was discontinous. Vascular endothel ia became swollen and the cell junctions widened or were destroyed in groups A and B. The incidence of osteonecrosis in group B (88.9%) was higher than that in group C (22.2%, P lt; 0.05). There was no osteonecrosis occurred in groups A and D . Conclusion Methylprednisolone combined with l ipopolysaccharide can induce typical rabbit model for early avascular necrosis of femoral head.
Objective To investigate the influence of collagen on the biomechanics strength of tissue engineering tendon. Methods All of 75 nude mice were madethe defect models of calcaneous tendons, and were divided into 5 groups randomly. Five different materials including human hair, carbon fibre (CF), polyglycolic acid (PGA), human hair and PGA, and CF and PGA with exogenous collagen were cocultured with exogenous tenocytes to construct the tissue engineering tendons.These tendons were implanted to repair defect of calcaneous tendons of right hind limb in nude mice as experimental groups, while the materials without collagenwere implanted to repair the contralateral calcaneous tendons as control groups. In the 2nd, 4th, 6th, 8th and 12th weeks after implantation, the biomechanicalcharacteristics of the tissue engineering tendon was measured, meanwhile, the changes of the biomechanics strength were observed and compared. Results From the 2nd week to the 4th week after implantation, the experimental groups were ber than the control groups in biomechanics, there was statistically significantdifference (Plt;0.05). From the 6th to 12th weeks, there was no statisticallysignificant difference between the experiment and control groups (Pgt;0.05). Positivecorrelation existed between time and intensity, there was statistically significant difference (Plt;0.05). The strength of materials was good in human hair,followed by CF, and PGA was poor. Conclusion Exogenous collagen can enhance the mechanics strength of tissue engineering tendon, and is of a certain effect on affected limb rehabilitation in early repair stages.
【Abstract】Objective To investigate the effect of ischemia on the treatment of advanced body and tail carcinoma of pancreas. Methods In operation the proximal spleen artery was ligated, a chemotherapy pump was installed to connect the distal spleenic artery and urea solution (40%) was injected through the device during and after operation. The pathology and pathophysiology change in dogs were observed. Results All the eight dogs studied were alive after operation, no serious complication appeared, pancreatic cells were replaced by fibrosis. Conclusion Infusion of 40% urea solution is a safe and effective ischemic method, it can lead to all sorts of pancreatic cell necrosis and fibrosis. It may be a good madality in the treatment of advanced pancreatic carcinoma.
ObjectiveTo research the procedure for creating an animal model of mitral regurgitation by implanting a device through the apical artificial chordae tendineae, and to assess the stability and dependability of the device. MethodsTwelve large white swines were employed in the experiments. Through a tiny hole in the apex of the heart, the artificial chordae tendineae of the mitral valve was inserted under the guidance of transcardiac ultrasonography. Before, immediately after, and one and three months after surgery, cardiac ultrasonography signs were noted. Results All models were successfully established. During the operation and the follow-up, no swines died. Immediately after surgery, the mitral valve experienced moderate regurgitation. Compared with preoperation, there was a variable increase in the amount of regurgitation and the values of heart diameters at a 3-month follow-up (P<0.05). ConclusionIn off-pump, the technique of pulling the mitral valve leaflets with chordae tendineae implanted transapically under ultrasound guidance can stably and consistently create an animal model of mitral regurgitation.
Objective To investigate the relationship between surgical operation and hypophosphatemia, to observe the possible damage of hypophosphatemia and to assess the value of postoperative phosphate supplementation. Methods Sixty four male SD rats were randomly divided into 2 groups, Group Ⅰ, drinking a specially prepared solution to reduce their phosphate storage, Group Ⅱ, drinking water as a control. All received common bile duct ligation 3 weeks later. The serum biochemical data including phosphate level were obtained before and after operation. Then half of rats in each group were supplied with NaH2PO4 5-day survival rates were analyzed with statistic methods and their vital organs were observed under electron microscope. Results The phosphate level of each group was descended after operation. The group with phosphate shortage before operation (group Ⅰ) had a greatest fall of phosphate and average arterial pressure. The phosphate-supplied rats had a minor change of vital organs under electron microscope scan and higher 5-day survival rate compared to others in this group.Conclusion Abdominal surgery may induce postoperative hypophosphatemia, especially when the phosphate has been lacking before operation. Severe hypophosphatemia, superimposed on surgical trauma, enhances the damage to the body. Prompt supplement of phosphate will improve the prognosis of surgical operation.
Objective To establish a repeatable, simple, and effective model of rat crush injury and crush syndrome (CS) so as to lay a foundation for further study on CS. Methods A total of 42 female Sprague Dawley rats (2-month-old, weighing 160-180 g) were divided randomly into the control group (n=6) and experimental group (n=36). The rats of the experimental group were used to establish the crush injury and CS model in both lower limbs by self-made crush injury mould. The survival rate and hematuria rate were observed after decompression. The biochemical indexes of blood were measured at 2, 4, 8, 12, 24, and 48 hours after decompression. The samples of muscle, kidney, and heart were harvested for morphological observation. There was no treatment in the control group, and the same tests were performed. Results Seven rats died and 15 rats had hematuria during compression in the experimental group. Swelling of the lower limb and muscle tissue was observed in the survival rats after reperfusion. The liver function test results showed that the levels of alanine transaminase and aspartate aminotransferase in the experimental group were significantly higher than those in the control group (P lt; 0.05). The renal function test results showed that blood urea nitrogen level increased significantly after 2 hours of decompression in the experimental group, showing significant difference when compared with that in the control group at 12, 24, and 48 hours after decompression (P lt; 0.05); the creatinine level of the experimental group was higher than that of the control group at 4, 8, 12, and 24 hours, showing significant difference at 8, 12, and 24 hours (P lt; 0.05). The serum K+ concentration of the experimental group was higher than that of the control group at all time, showing significant difference at the other time (P lt; 0.05) except at 2 hours. The creatine kinase level showed an increasing tendency in the experimental group, showing significant difference when compared with the level of the control group at 4, 8, 12, and 24 hours (P lt; 0.05). The histological examination of the experimental group showed that obvious edema and necrosis of the muscle were observed at different time points; glomeruli congestion and swelling, renal tubular epithelial cell degeneration, edema, necrosis, and myoglobin tube type were found in the kidneys; and myocardial structure had no obvious changes. Conclusion The method of the crush injury and CS model by self-made crush injury mould is a simple and effective procedure and the experimental result is stable. It is a simple method to establish an effective model of rats crush injury and CS.
Objective To build animal models of keloid by method of tissue engineering and to discuss the feasibility of using it in clinical and lab researches. Methods Fibroblasts(FB) were isolated from keloids and cultured. The seventh and eighth generation of the cultured FBs were inoculated into the copolymers of polylactic acid and polyglycolic PLGA. After being cultured in rotatory cell culture system （RCCS）for 1 week,the FB was transplanted into athymic mice. The specimens were obtained 4 weeks and 8 weeks and examined histologically. Results All mice survived.The collagen patterns of all keloids were pressed in every specimen obtained 8 weeks. Fibrocytes andFB were observed in specimens by electronic microscope. There were abundent rough endoplasmic reticulum (RER) in FB， which indicated that FB’s capability of synthesizing and secreting collagen was preserved and the cellular characteristicwas remained. Conclusion There is a good affinity between PLGAand FB. The composition of PLGA and FB can form keloids in athymic mice,so that it deserves further researching and developing.