To valuate cerebral protection by retrograde cerebral perfusion (RCP) via superior vena cava,the study results for the last ten years have been reviewed.RCP is regarded as an assistant method in deep hypothermic circulatory arrest(DHCA) in that it provides partial brain blood flow,maintains a low brain temperature,optimizes cerebral metabolic function during DHCA by supplying oxygen and some nutrient and removal of catabolic products;it also reduces the incidence of cerebral embolization by flushing out air...
OBJECTIVE: To investigate availability of deep freeze stored allogenic tendon with sheath grafting in repairing the tendon and sheath defect in the II area of flexor digitorum tendon. METHODS: Sixty chickens with tendon and sheath defect were divided into 2 groups randomly, group A was treated with allogenic grafting and group B was treated with autogenic grafting, these two groups were divided into two subgroups respectively, they were, group A1 allogenic tendon with whole sheath grafting, group A2 allogenic tendon with partial sheath grafting, group B1 autogenic tendon with whole sheath grafting and group B2 autogenic tendon with whole sheath grafting. All the allogenic grafts were treated by deep freeze. Histomorphological study, histoimmunological study and slipping function of the grafts were measured after operation. RESULTS: In group A1 and B1, the local reaction was sever, the nutrition of tendon graft was barricaded by the whole sheath resulting in adhesion, degeneration and necrosis. In group A2 and B2, the tendon graft healed well and little adhesion existed between tendon and sheath. The results showed that there were significant differences between tendon grafting with whole sheath and tendon grafting with partial sheath. CONCLUSION: Deep freeze store can reduce the immunogenicity of allogenic tendon with sheath. Allogenic tendon with partial sheath grafting can be used as a new biological material for repairing the tendon and sheath defect.
Objective To evaluate which is better method zymogen or low temperature frozen in removing vascular endothelial cell so as to lay a foundation for creating a kind of brace which is not to be rejected and the same as own blood vessel. Methods Fresh and not damaged umbilical blood vessel was collected from natural labour women, human umbilical blood vessel was remove carefully from normal foetus, then was put into disinfectant at 37℃ for 24 hours. They were divided into 3 groups:normal group(NG),zymogen group(ZG) and low temperature frozen group(LG). ZG: 0.1% collagenⅡ enzyme was addedin umbilical blood vessel and closed the both sides and the vascular endothelialcell was removed in 37℃ water. LG:Umbilical blood vessel was put into liquidnitrogen for 24 hours after frozened step by step, and then it was put into 37℃ water for 30-60 s and the vascular endothelial cells were washed away by normal saline. NG:Umbilical blood vessel was kept into 4℃ Kerb’s liquid. The bacteria were culturedin each group. The samples were stained by HE,elastic fiber and collagen fiberwere observed by light and scanning electron microscope. The difference of compliance was compared. Human leukocyte antigen ABC(HLA-ABC) and HLA-DR were observed by immunohistochemical method and the expression of antigen of umbilical blood vessel was analysed. Results In LG, umbilical vascular endothelial cells were removed completely; artery showed vertical smooth muscle and vein showed elastic membrane. InZG, umbilical vascular endothelial cells were removed completely after 20 minutes;artery showed vertical smooth muscle cells and vein showed lower endothelial layer. The vascular compliance in LG was higher than that in NG, and the latter was also higher than that in ZG,but showing no significant differences (Pgt;0.05). The compliance of umbilical vein was 2-3 times as much asthat of umbilical artery.The expression of HLA-ABC and HLA-DR in LG andZG were lower than that in NG, showing significant differences (Plt;0.01). Conclusion Low temperature frozen methodand zymogen method(0.1% collagen Ⅱ enzyme for 20 min) can remove vascular endothelial cells of human umbilical blood vessel completely.Low temperature frozenmethod was better than zymogen method.
Objective To observe the configuration and viability of full thickness human fetal retina after short-, mid- and long-term preservation. Methods Twenty-two full thickness human fetal retinae of gestational age of 12-24 weeks were coated by glutin and cut into 88 pieces, and then preserved in Ames' solution, DX solution, -80℃ refrigerator or under cryopreservation condition. The cell viability of retinal neuroepithelial layer was determined by trypan blue staining, retinal configuration was determined by light microscope and electromicroscope. Results The viability of neuroepithelial layer was (94.79plusmn;2.85) % in fresh fetal retina, gt;80% in Ames' solution within 4 hours, and gt;77% in DX solution within 2 days. There was no significant difference between those solution-preservations and the fresh fetal. In -80℃ refrigerator, the viability was (65.83plusmn;5.06)% after 7 days, and then dropped to (57.54plusmn;16.18)% at the end of the first month. Under the cryopreservation condition, the viability was (69.46plusmn;9.31)% at the end of first month. Light and transmission electron microscopy had not deteced any abnormals in the full thickness human fetal retina preserved in Ames' solution within 2 hours, but showed clear retinal layers with bigger intercellular space after preserved in DX solution for 2 days, in -80℃ refrigerator for 7 days and under cryopreservation condition for 1 month. Conclusion Ames' solution and DX solution can preserve good viability and configuration of full thickness human fetal retina in a certain time period.
Objective Bone marrow mesenchymal stem cells (BMSCs) play an important role in repairing nerve injury, meanwhile external temperature has significant effect on BMSCs transplantation, prol iferation, and differentiation. To investigate the effect of BMSCs transplantation and mild hypothermia on repair of rat spinal cord injury (SCI). Methods Forty-five female adult SD rats (weighing 200-250 g) were made the models of hemitransection SCI and divided randomly into 3 groups according to different treatments: group A (SCI group), group B (BMSCs transplantation group), and group C [BMSCs transplantation combined with mild hypothermia (33-35 ) group]. At 1, 2, 4, 6, and 8 weeks after injury, the fuction of hind l imb was evaluated with Basso Beattie and Bresnahan (BBB) score and incl ined plane test. At 4 weeks after injury, histopathology and BrdU immunohistochemistry staining were performed. At 8 weeks after injury, horseradishperoxidase (HRP) retrograde nerve trace and transmission electron microscope (TEM) testing were performed to observe the regeneration of axon. Results After 4 weeks, the function of hind l imb obviously recovered in groups B and C, there were significant differences in BBB score between groups B, C and group A (P lt; 0.05), between group B and group C (P lt; 0.05). There was no significant difference (P gt; 0.05) in tilt angle among 3 groups after 1 and 2 weeks, and there were significant differences (P lt; 0.05) among 3 groups after 4 weeks. HE staining showed that significant cavity could be seen in group A, l ittle in group B, and no cavity in group C. BrdU immunohistochemistry staining showed that the number of positive cells was 0, 90.54 ± 6.23, and 121.22 ± 7.54 in groups A, B, and C, respectively; showing significant differences (P lt; 0.01) among 3 groups. HRP retrograde neural tracing observation showed that the number of HRP positive nerve fibers was 10.35 ± 1.72, 43.25 ± 2.65, and 84.37 ± 4.59 in groups A, B, and C, respectively, showing significant differences (P lt; 0.01) among 3 groups. TEM observation showed that a great amount of unmyel inated nerve fibers and myel inated nerve fibers were found in central transverse plane in group C. Conclusion The BMSCs transplantation play an impontant role in promotion of recovering the function of hind l imb after SCI, and mild hypothermia has synergism effects.