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.
The canine saphaneous skin flap was used as a model in this experiment. The cutaneous autograft would give long-term survival, whereas the allograft without pretreatment would only survive 10. 2±1.9 days from its transplantation. If the pretreatment consisted of the use of immunosuppressive agent as PHA or infusion of dexamesone, the survival days of the allografts could be prolonged to 15.1±2.5 and 13.7±2.8, respectively(Plt;0.01). The histological examination gave the evidence that drug perfusion delayed the rejection.
Objective To study the effect of dexamethasone to protect flaps from an ischemia-reperfusion injury and elucidate its mechanism of regulating the death course of the neutrophils.Methods The rats were randomly divided into 3 groups.The vein of the rat was clamped for 8 h after the flap had formed. Group A: the normal flap; Group B: the saline control flap; Group C: the treatment flap with dexamethasone. The survival area of the flaps was measured at 7 days; the apoptotic and necrotic neutrophils,tumor necrosis factor α （TNF-α）, and interleukin 10 （IL-10） concentrations were measured. Results The flap survival areas in Groups A and C were larger than those in Group B. The apoptotic neutrophils in Group B were fewer than those in Groups A and C on the 1st and 3rd days after operation; however, they were more in number in Group B than in groups A andC on the 6th day. The necrotic cells in Group B were more in number than those in Groups A and C. In Group B, the plasma TNF-α concentration reached the maximum level at 1 h,while the IL-10 level reached the lowest 3 h after the reperfusion. In Group C, the TNF-α concentration was lower than that in Group B and decreased dramatically at 6 h. The IL-10 concentration was the lowest at 1 h, and increased rapidly at 3 h. Thus, ischemia reperfusion could injure the flaps, probably through the abnormal action of the neutrophils, such as the disordered secretion of the cytokines and abnormal death course of the neutrophils. Conclusion Dexamethasone can protect the flap from an ischemia-reperfusion injury by its regulation for the neutrophil function.
Objective To summarize the methods and experiences of surgical treatment of aortic arch diseases with four branches aortic graft under deep hypothermia circulatory arrest （DHCA） and antegrade selective cerebral perfusion （ASCP）. Methods In 2004 from September to December, surgical treatment of 12 patients with 7 aortic aneurysm（4 cases with ascending aorta and aortic arch aneurysm, 3 cases with aneurysm of aortic isthmus） and 5 aortic dissection（DeBakey Ⅰ 1 case, DeBakey Ⅱ 3 cases, DeBakey Ⅲ 1 case） were collected in Gunma Prefectural Cardiovascular Center. All operations were carried out under DHCA and ASCP, and four branches aortic graft were used to replace the aortic arch. The Bentall procedure, total and partial arch replacement and elephant trunk technique were undertaken in different patients. Results Total 12 patients recovered from the great vessel diseases smoothly without severe cerebral and other systematic complications, the time of operation was 5.5±1.7 h, the period of DHCA was 42.2±12.9min, 4 cases with no blood transfusion, the time of hospitalization was 22.3±7.2d. Conclusion ASCP is a safe. and effective method of cerebral protection during circulation arrest, and four branches aortic graft may shorten the time of DHCA and simplify the procedure of aortic arch replacement.
Objective To study the clinical and angiographic features in ST Segment Elevation Myocardial Infarction (STEMI) patients with spontaneous reperfusion. Methods A total of 519 patients with STEMI underwent Primary percutaneous coronary intervention (PCI) from January 2006 to December 2009 in Anzhen Hospital were enrolled. All patients were divided into the spontaneous reperfusion group (TIMI flow gradeⅢ ) and the non-spontaneous reperfusion group (TIMI flow grade 0-Ⅱ ) according to the TIMI flow grade before primary PCI. The incidence rate of spontaneous reperfusion through coronary angiography before primary PCI was observed, and the clinical relevant factors and angiographic lesion features of spontaneous reperfusion were analyzed. Results There were significant differences in age, CTnI peak value, high thrombus burden, and lesion location in distant LAD (P=0.000, 0.000, 0.002, 0.000, and 0.003, respectively) between the two groups. But there were no significant differences in gender, hypertension, diabetes mellitus, smoking history, hyperlipemia, angina pectoris history, culprit vessel distribution, lesion distribution in LCX and RCA, and collateral circulation between the two groups (Pgt;0.05 for all). Conclusion Compared to the patients without spontaneous reperfusion, patients with spontaneous reperfusion are younger in age, lower in CTnI peak value, and heavier in thrombosis burden, with culprit lesions mostly located in the distant LAD.
