ObjectiveTo study the changes of levels of α subunits of stimulatory (Gsα) and inhibitory guanine nucleotide binding protein (Giα) in newborn guinea pig (0 2 days old) myocardium undergoing global ischemic reperfusion, and influences on the changes by St.Thomas Ⅱ and cold blood cardioplegic solution.MethodsThirty newborn guinea pigs were randomly assigned to three groups. GroupⅠ ( n = 10): the newborn hearts suffered by hypothermic global ischemia; group Ⅱ( n =10): the newborn hearts arrested by St. Thomas Ⅱ , and group Ⅲ ( n = 10): the newborn hearts arrested by cold blood cardioplegic solution. Levels of Gsα and Giα were investigated with Western blot analysis.ResultsNo differences of levels of Gsα and Giα were found in three groups before ischemia ( P gt;0.05). The level of Gsα after ischemia was significantly decreased than before ischemia in groupⅠand group Ⅱ ( P lt; 0 01), whereas no pronounced changes in group Ⅲ ( P gt;0.05) were noted after ischemia. The level of Gsα in group Ⅲ was not significantly changed after reperfusion compared with before ischemia( P gt;0 05), and it was much higher than those in groupⅠand group Ⅱ ( P lt; 0 01). Level of Giα was found not markedly changed in group Ⅲ after reperfusion compared with that before ischemia, but was notable higher in groupⅠand group Ⅱ( P lt;0.01). ConclusionsSignificant decrease of level of Gsα, whereas marked increase of level of Giα are found in myocardium of newborn guinea pig undergoing hypothermic (20℃) ischemic reperfusion. No impact of St. Thomas Ⅱ on these changes is verified, but recovery to the level of Gsα and Giα before ischemia is achieved by cold blood cardioplegic solution after ischemia and reperfusion. Unbalance between Gsα and Giα is the one of the mechanisms of ischemic reperfusion injury for immature myocardium.
Objective To summarize the visual outcome of patients with severe ocular trauma treated with vitreous surgery. Methods Clinical data of 188(191 eyes) with severe ocular trauma treated with vitreous surgery in a period from November 1996 to April 1998 were analysed retrospectively. Results The study included penetrating injury in 56 eyes, foreign bodies in the posterior segment in 70 eyes, blunt injury in 41 eyes , and globe rupture in 24 eyes. Main complications included endophthalmitis in 35 eyes, choroidal bleeding in 20 eyes, retinal detachment in 60 eyes, and vitreous hemorrhage in 97 eyes. Post-opera-tively, out of 188 eyes, except for 3 of patients too young to examine, visual acuity improved in 133(70.7%), including 85(45.2%) with visal acuity 0.02-1.0, 46(24.5%) remained unchanged; and 9(4.8%) had worse vision. Among 34 with no-light-perception, 12 had light-perception or over. Conclusion A majority of severe trauma eyes can be salvaged with considerable visual recovery after adequate and timely vitreous surgery. (Chin J Ocul Fundus Dis,1999,15:4-6)
Objective To investigate the protective effects of antitumor necrosis factor-α antibody （TNF-αAb） on lung injury after cardiopulmonary bypass （CPB） and their mechanisms. Methods Forty healthy New Zealand white rabbits，weighting 2.0-2.5 kg，male or female，were randomly divided into 4 groups with 10 rabbits in each group. In groupⅠ，the rabbits received CPB and pulmonary arterial perfusion. In group Ⅱ，the rabbits received CPB and pulmonary arterial perfusion with TNF-αAb. In group Ⅲ，the rabbits received CPB only. In group Ⅳ，the rabbits only received sham surgery. Neutrophils count，TNF-α and malondialdehyde （MDA） concentrations of the blood samples from the left and right atrium as well as oxygenation index were examined before and after CPB in the 4 groups. Pathological and ultrastructural changes of the lung tissues were observed under light and electron microscopes. Lung water content，TNF-α mRNA and apoptoticindex of the lung tissues were measured at different time points. Results Compared with group Ⅳ，after CPB，the rabbitsin group Ⅰ to group Ⅲ showed significantly higher blood levels of neutrophils count，TNF-α and MDA（P＜0.05），higherTNF-α mRNA expression，apoptosis index and water content of the lung tissues （P＜0.05），and significantly lower oxyg-enation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with group Ⅱ，after CPB，the rabbits in groups Ⅰ and Ⅲ had significantly higher blood concentrations of TNF-α （5 minutes after aortic declamping，220.43±16.44 pg/ml vs.185.27±11.78 pg/ml，P＜0.05；249.99±14.09 pg/ml vs.185.27±11.78 pg/ml，P＜0.05），significantly higher apoptosis index （at the time of CPB termination，60.7‰±13.09‰ vs. 37.9‰±7.78‰，P＜0.05；59.6‰±7.74‰ vs. 37.9‰±7.78‰，P＜0.05），significantly higher blood levels of neutrophils count and MDA （P＜0.05），significantly higher TNF-α mRNA expression and water content of the lung tissues （P＜0.05），and significantly loweroxygenation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with groupⅠ，rabbits in group Ⅲ had significantly higher above parameters （P＜0.05） but lower oxygenation index （P＜0.05） only at 30 minutes after the start of CPB. Conclusion Pulmonary artery perfusion with TNF-αAb can significantly attenuate inflammatory lung injury and apoptosis of the lung tissues during CPB.
组织工程的提出、建立和发展,为最终实现脊髓损伤的修复和真正意义上的结构、形态与功能重建开辟了新的途径。支架的生物活性、三维结构和表面微观结构,材料的降解性等众多因素都对细胞增殖,分化和组织形成有明显影响。组织工程的发展也将改变传统的医学模式,使得再生医学得以进一步发展,并最终用于疾病的治疗。
Objective To investigate the maximum tolerance limit of rats to hepatic inflow occlusion with portal vein blood bypss (PBB) in normothermia. Methods First. A new animal model was established, the animal survival rate were calculated following 7 days of reperfusion after hepatic inflow occlusion of 30, 60, 90, 100, 110, 120 min or portal triad clamping (PTC) of 30 min. And then, the hepatic energy metabolism (RCR, P/O, ATP, AKBR) was studied following 30, 90, 120 min of ischemia or 1, 6, and 24 hours of reperfusion after the ischemia. According to the reversibility of the hepatic motochondrial function injury and maximum as long as a period of liver warm ischemia of all animal postoperative 7 days survial, the safe limit of rat to hepatic inflow occlusion was evaluated. Results The survival rate on postoperative 7 days was one hundred percent subjected to 30, 60 and 90 min of hepatic inflow occlusion, and 50, 30, 20 percent in 100, 110, 120 min, respectively, the survival rate in rats with 30 min of portal triad champing was about 40 percent. The parameters of hepatic motochondrial function reflecting the degree of liver damage to ischemia showed significantly different as compared to sham group. The functional lesion was exacerbated during inital reperfusion, then was restored progressively in PBB-30 min and PBB-90 min groups, but was maintained low level in PBB-120 min and PTC-30 min groups.Conclusion The 90 minutes is the maximum limit of rats to hepatic inflow occlusion in normothermia.
Objective To investigate the mRNA expression of ciliary neurotrophic factor on the retina during injury and repair of optic nerves in rats. Methods Thirty-five healthy SD rats were randomly divided into 3 groups: 5 in the control group, 15 in the simply transected optic nerve group and 15 in the optic nerve-sciatic nerve anastomosis group. The simply transected and optic nerve-sciatic nerve anastomosed models were set up, and the retinal tissues of all of the rats were taken out after 3, 7 and 14 days, respectively; and the mRNA expression of CNTF in the 3 groups were observed by semiquantitative reversal transcription-polymerase chain reaction method. Results A minimum expression of CNTF mRNA was found in the retinae of the control group, and the increased rates of expression were found in the retinae of the simple transection of optic nerve group with the increase rate of 100%, 594%, and 485% on the 3rd, 7th, and 14th day respectively after the operation, while in optic nerve-sciatic nerve anastomosis group, the increase rates were found to be 258%, 752% and 515% on the 3rd, 7th, and 14th day respectively after the operation. Conclusion Retinal neurons can respond to axonal reaction of retinal ganglion cells by up-regulate endogenous CNTF after the injury of the optic nerves, which may provide a theoretic base for the application of the exogenous CNTF. (Chin J Ocul Fundus Dis，2004，20：355-357)
Objective To study the efect of IH764-3 on ischemia-reperfusion (I/R) injury in rat liver. Methods Rats were divided into 3 groups, the control group was not subjected to ischemia and no treatment was given. I/R injury group was subjected to 40 minutes ischemia followed by reperfusion for 120 minutes. The IH7643 group (40mg/kg) was administred at ischemia and reperfusion. Results In the IH764-3 group, sereum levels of ALT, AST, AKP and γ-GT were significantly lower than those in the I/R group. Energy charge level recovery was significantly higher with IH7643 (P＜0.05), hepatic ultrastructure was better preserved with IH764-3. Conclusion IH764-3 may be useful in the treatment of hepatic ischemia reperfusion injury
OBJECTIVE To observe the ultrastructural changes and number of satellite cells in different muscles with different denervation interval and investigate the mechanism of denervation atrophy. METHODS Muscles of different denervation interval were harvested, which were 6 biceps brachii and 6 abductor digiti minimi. The ultrastructure of the samples were observed under transmission electron microscope. The number of nucleus and satellite cells were counted to calculate the percentage content of satellite cells. RESULTS In early stage of denervation, the myofilament and sarcomere of the majority were well oriented. The nucleoli of some muscle cell nucleus were enlarged and pale. Vacuolarization was also seen in some mitochondria. There was no obvious proliferation of collagen fiber around myofibers. After denervation of half a year, rupture and disorientation of myofilament was seen. The nucleus became smaller, dark stained, and some of them were condensed. There was proliferation of fibroblasts, adipose cells and collagen fibers around myofibers. Motor endplate was not recognized one year after denervation. In the early stage of denervation, satellite cell percentage of the two muscles was relatively high. It then declined with time. One year after denervation, satellite cells were scarcely detected. Comparison of the curves for satellite cell declination in two muscles revealed that the declination of the abductor digiti minimi was faster than that of biceps brachii. Decrease of the former started 3 months after denervation, while the latter started after 6 months. CONCLUSION Disappearing of motor endplate and proliferation of collagen fibers are main factors that affect the treatment outcome in late cases. Decrease of satellite cell number is another cause. The correlation of less satellite cell in abductor digiti minimi and poorer recovery of hand intrinsic muscles indicates that increment of satellite cells in long-term denervated muscles may be one of the effective measures to improve treatment outcome.