超声心动图评价大鼠异位移植心脏急性排斥反应的初步实验研究

目的:探讨高频超声心动图评价大鼠颈部异位移植心脏的急性排斥反应的价值。方法:采用高频超声心动图测量17只同种异体移植及6只同系移植心脏测量左室内径、心肌厚度、左室重量和心功能等。6只同系移植大鼠和9只同种异体移植大鼠,分别于移植术后第1、3、5天,采用高频超声对上述指标进行测量,第五天测量完毕后处死并做病理检查。另8只同种异体移植心脏,分别于移植术后第1、3天各测量一次,第3天测量完毕后处死做病理学检查,超声指标与病理结果相对照。结果:①同种异体移植术后,随着移植时间的延长,左室心肌厚度和左室重量逐渐增加,左室内径减小,射血分数无显著性改变;②术后第3天,组织学检查表明已有排斥反应发生,超声检查显示室壁厚度与左室重量明显增加,而常规心脏触诊未能及时发现排斥反应;③随着组织学分级加重显示的排斥,左室心肌厚度与左室重量有显著的增加。结论:室壁厚度和左室重量为超声评价排斥反应发生的敏感、准确指标。高频超声为心脏移植实验研究评价排斥反应提供了一种较为简便可靠的观察方法,为临床上心脏移植的排斥反应的超声评价提供了依据。     

脂氧素A4对心肌缺血再灌注损伤的保护作用

Objective To investigate the roles of lipoxin A4, an endegenous lipid mediator with wide anti-inflammatory fea- tures, in attenuating myocardial ischemia-reperfusion injury and the possible mechanisms. Methods Thirty male KM mice were divid- ed randomly into three groups, 10 in each: ischemia-reperfusion group (group A), lipoxin A4 (0.1 mg/kg) group (group B) and Zn- PP (Zinc protoporphyrin Ⅸ, 25 mg/kg)phus lipoxin A4 (0.1 mg/kg)group (group C). A ischemia-reperfusion heart model was de- veloped by ligating the lift anterior descending branch of the coronary artery. A dine of 10% dehydrated alcohol in 0.2 ml for group A, a dose of isochoric lipoxin A4 for group B and a dose of isochoric ZnPP + lipoxin A4 for group C was infused into the ascending aorta through a catheter, which was kpassing the right common carotid artery, 30 minutes after reperfusion. The concentration of serum TNF-α, activities of serum crestine kinase(CK) and lactate dehydrogenase (LDH), activities of myeloperoxidase (MPO) and malond- ialdehyde (MDA) and the cell apoptosis rate in the myocardial tissue were measured 5 hours after reperfusion. Pathological features of the inflammatory infiltration in the myocardium were also observated.Results As compared with group A, the inflammatoryry infiltra- tion in the ischemic and necrotic regions tithe myocardium was reduced, with group C in the intermediate range. The serum activities of CK and LDH wine significantly lower in group B and C than that in group A, and the lowest activities were detected in group B. Similar findings were observed for MPO, an indicator for neutrophil infiltration, and MDA, an indictor for cell injury caused by oxy- gen radicals, in the myocardium. The concentration of TNF-α and the rate of cadiocyte apoptosis were decreased significantly in group B(P < 0.01). ZnPP, an inhibitor of heine oxygenase (HO)-1, attenusted the above protective effects of lipoxin A4 significantly (P<0.05). Conclusion Lipoxin A4 has protective effects against myocardial ischemia-reperfusion injury, and HO-1 may have a potential role in the protectve mechanisms of lipoxin A4, probably pertly by means of reducing the production of reactive oxygen spe- cies and TNF-α, decreasing the activation and infiltration of neutrophils, alleviating inflammatory damage and avoiding apoptosis.     

羟甲唑啉在鼻内镜手术中的应用

目的：探讨经甲唑啉(商品名：达芬霖)在鼻内镜手术中的应用价值。方法：观察在68例鼻内镜手术中应用经甲唑啉对患者的脉搏、纤毛运动的影响及出现反跳的时间。结果：在经甲唑啉应用前后，68例患者的脉搏变化差异无显著性意义(P＞0．05)；10例慢性鼻窦炎患者的纤毛移动率差异无显著性意义(P＞0．05)；降低鼻血流量约50％；作用持续时间长达6h。结论：经甲唑啉作为鼻教膜血管减充剂和麻醉辅助药，常规用于鼻内镜手术，安全、有效。     

去胸腺小鼠模型的建立与改进

目的建立简单易行、稳定可靠的去胸腺小鼠模型.方法采用术中呼吸机辅助呼吸,术后胸管抽气的方法建立成年去胸腺小鼠模型,结果实验20次,成功16例,成功率为80%.结论用该方法建立去胸腺小鼠模型成活率高,胸腺切除彻底,效果满意.     

脂氧素A4对心肌缺血再灌注损伤的保护作用

Objective To investigate the roles of lipoxin A4, an endegenous lipid mediator with wide anti-inflammatory fea- tures, in attenuating myocardial ischemia-reperfusion injury and the possible mechanisms. Methods Thirty male KM mice were divid- ed randomly into three groups, 10 in each: ischemia-reperfusion group (group A), lipoxin A4 (0.1 mg/kg) group (group B) and Zn- PP (Zinc protoporphyrin Ⅸ, 25 mg/kg)phus lipoxin A4 (0.1 mg/kg)group (group C). A ischemia-reperfusion heart model was de- veloped by ligating the lift anterior descending branch of the coronary artery. A dine of 10% dehydrated alcohol in 0.2 ml for group A, a dose of isochoric lipoxin A4 for group B and a dose of isochoric ZnPP + lipoxin A4 for group C was infused into the ascending aorta through a catheter, which was kpassing the right common carotid artery, 30 minutes after reperfusion. The concentration of serum TNF-α, activities of serum crestine kinase(CK) and lactate dehydrogenase (LDH), activities of myeloperoxidase (MPO) and malond- ialdehyde (MDA) and the cell apoptosis rate in the myocardial tissue were measured 5 hours after reperfusion. Pathological features of the inflammatory infiltration in the myocardium were also observated.Results As compared with group A, the inflammatoryry infiltra- tion in the ischemic and necrotic regions tithe myocardium was reduced, with group C in the intermediate range. The serum activities of CK and LDH wine significantly lower in group B and C than that in group A, and the lowest activities were detected in group B. Similar findings were observed for MPO, an indicator for neutrophil infiltration, and MDA, an indictor for cell injury caused by oxy- gen radicals, in the myocardium. The concentration of TNF-α and the rate of cadiocyte apoptosis were decreased significantly in group B(P < 0.01). ZnPP, an inhibitor of heine oxygenase (HO)-1, attenusted the above protective effects of lipoxin A4 significantly (P<0.05). Conclusion Lipoxin A4 has protective effects against myocardial ischemia-reperfusion injury, and HO-1 may have a potential role in the protectve mechanisms of lipoxin A4, probably pertly by means of reducing the production of reactive oxygen spe- cies and TNF-α, decreasing the activation and infiltration of neutrophils, alleviating inflammatory damage and avoiding apoptosis.     

增加受者体内一氧化碳含量在减轻小鼠移植心缺血再灌注损伤中的作用和机制

目的 观察心脏移植前用二氯甲烷(MC)灌胃增加受者体内一氧化碳含量在减轻小鼠移植心缺血再灌注损伤中的作用及其机制.方法 以Balb/c小鼠作为供、受者,建立颈部异位心脏移植模型.实验共分为4组,分别为MC 100 mg组(n=10)、MC 500 mg组(n=12)、橄榄油组(n=10)和正常对照组(n=5).前3组在麻醉前3 h分别用经橄榄油稀释的MC 100 nag/kg、MC 500mg/kg及单纯橄榄油0.15 ml对受者进行灌胃处理,然后行颈部异位心脏移植;正常对照组小鼠仅作麻醉处理,不进行心脏移植.分别于灌胃后0、1、3、6、12和24 h剪尾采血,测定血液中CO的含量[用碳氧血红蛋白(COHb)占总血红蛋白的百分比表示],并于相应时间点取心肌组织,检测心肌组织中CO的含量;各组移植后3和24 h分别处死半数受者,检测移植后3和24 h血清中肌钙蛋白I(cT-nI)、心肌组织中肿瘤坏死因子α(TNF-α)、白细胞介素10(IL-10)、细胞凋亡与相关基因Bcl-2和Bax mRNA以及核因子κB(NF-κB)的表达,并观察移植心心肌的超微结构.结果 与橄榄油组比较,MC 100 mg和MC 500 mg组受者血液中COHb浓度与心肌组织中CO含量明显升高,均在灌胃后3h达到峰值;MC 100 mg组和MC 500mg组受者心脏移植后3和24h,能显著降低血清中cTnI水平(P<0.01),并以MC 500 mg组降低最为明显;可明显下调促炎症基因TNF-α mRNA水平(P<0.01),而抗炎症基因IL-10 mRNA上调不明显(P>0.05),同时可以显著上调抗凋亡基因Bcl-2 mRNA水平(P<0.01),并抑制促凋亡基因Bax mRNA的转录(P<0.01);心肌超微结构损伤明显减轻.正常对照组可见少量NF-κB表达,而橄榄油组、MC 100 mg组和MC 500 mg组NF-κB活性均显著增强(P<0.01),但后三组之间NF-κB活性的差异无统计学意义(P>0.05).结论 诱导受者体内增加CO含量能通过其抗炎症和抗凋亡功能而减轻移植心缺血再灌注损伤;但与抑制NF-κB信号转导通路无关.     

受体诱导一氧化碳经PI3 K/Akt信号途径抑制冷缺血再灌注诱导的移植心细胞凋亡

目的 观察受体诱导一氧化碳(CO)对移植心冷缺血再灌注(I/R)损伤中细胞凋亡的影响,并探讨其机制.方法 以BALB/C小鼠建立同系移植心冷I/R损伤模型.受体麻醉前3 h以二氯甲烷(MC)500 mg/kg灌胃诱导CO(MC组,n=12),或橄榄油灌胃(IR组,n=12);在MC组的基础上受体在移植心恢复血供前1 h腹腔注射PI3K抑制剂LY294002(40 mg/kg,LY组,n=10)或二甲亚砜(DMSO组,n=10);检测移植后3、24 h移植心细胞凋亡指数(AI)、磷酸化Akt(p-Akt)蛋白、bcl-2与bax蛋白表达比值;设正常对照组(N组,n=5).结果 受体以MC灌胃后血液中碳氧血红蛋白(COHb)浓度与心肌组织CO含量均在3 h达到峰值,分别为(9.82±0.84)%和(2.25±0.08)pmol/mg;与IR组比较,MC组明显降低移植心AI[3 h:(8.65±2.01)%比(19.28±4.94)%,P＜0.01;24 h:(5.82±2.36)%比(10.54±3.66)%,P＜0.05]、激活Akt蛋白(3 h:P＜0.01;24 h:P＜0.05)、上调bcl-2/bax比值(3 h:1.97±0.16比0.46±0.07,P＜0.01;24 h:1.89±0.10比0.51±0.04,P＜0.01);与MC组比较,LY组明显增加AI[3 h:(17.95±4.92)%,P＜0.01;24 h:(9.75±3.14)%;P＜0.01]、抑制Akt蛋白激活(P＜0.01)、下调bcl-2/bax比值(3 h:0.47±0.06,P＜0.01;24 h:0.52±0.03,P＜0.01);DMSO组与MC组的各个指标差异无统计学意义(P＞0.05).结论 受体诱导C0能明显抑制冷I/R诱导的移植心细胞凋亡,其机制可能与通过PI3K/Akt信号途径上调bcl-2/bax比值有关.     

套管法与缝合法在建立小鼠颈部心脏移植模型的比较

目的:比较套管法与缝合法建立小鼠颈部心脏移植模型的优缺点。方法:分别用套管法和缝合法建立小鼠颈部异位心脏移植模型,从供心总缺血时间、手术成功率、手术难度和设备要求、术后血管内膜完整性、并发症发生率、术后生存期及总手术时间来比较。结果:经过25次套管法和39次缝合法实验,各自成功23例、28例,成功率分别是92%、72%;初学者在10倍目镜下就可完成套管吻合,后者要求术者有显微外科基础,至少需借助16倍目镜才能完成;套管法不损伤血管内膜,术后血管通畅性优于缝合法。结论:套管法可缩短供心总缺血时间,简化手术操作,成功率高,术后血管通畅性好,并发症无明显增加,手术时间无明显延长,是初学者建立该模型优先选择的方法。     

脂氧素A4对心肌缺血再灌注损伤的保护作用

Objective To investigate the roles of lipoxin A4, an endegenous lipid mediator with wide anti-inflammatory fea- tures, in attenuating myocardial ischemia-reperfusion injury and the possible mechanisms. Methods Thirty male KM mice were divid- ed randomly into three groups, 10 in each: ischemia-reperfusion group (group A), lipoxin A4 (0.1 mg/kg) group (group B) and Zn- PP (Zinc protoporphyrin Ⅸ, 25 mg/kg)phus lipoxin A4 (0.1 mg/kg)group (group C). A ischemia-reperfusion heart model was de- veloped by ligating the lift anterior descending branch of the coronary artery. A dine of 10% dehydrated alcohol in 0.2 ml for group A, a dose of isochoric lipoxin A4 for group B and a dose of isochoric ZnPP + lipoxin A4 for group C was infused into the ascending aorta through a catheter, which was kpassing the right common carotid artery, 30 minutes after reperfusion. The concentration of serum TNF-α, activities of serum crestine kinase(CK) and lactate dehydrogenase (LDH), activities of myeloperoxidase (MPO) and malond- ialdehyde (MDA) and the cell apoptosis rate in the myocardial tissue were measured 5 hours after reperfusion. Pathological features of the inflammatory infiltration in the myocardium were also observated.Results As compared with group A, the inflammatoryry infiltra- tion in the ischemic and necrotic regions tithe myocardium was reduced, with group C in the intermediate range. The serum activities of CK and LDH wine significantly lower in group B and C than that in group A, and the lowest activities were detected in group B. Similar findings were observed for MPO, an indicator for neutrophil infiltration, and MDA, an indictor for cell injury caused by oxy- gen radicals, in the myocardium. The concentration of TNF-α and the rate of cadiocyte apoptosis were decreased significantly in group B(P < 0.01). ZnPP, an inhibitor of heine oxygenase (HO)-1, attenusted the above protective effects of lipoxin A4 significantly (P<0.05). Conclusion Lipoxin A4 has protective effects against myocardial ischemia-reperfusion injury, and HO-1 may have a potential role in the protectve mechanisms of lipoxin A4, probably pertly by means of reducing the production of reactive oxygen spe- cies and TNF-α, decreasing the activation and infiltration of neutrophils, alleviating inflammatory damage and avoiding apoptosis.     

术前输注负载供者抗原的受者未成熟树突状细胞延长移植心存活时间的实验研究

目的:利用负载供者抗原的受者未成熟树突状细胞(imDC)干扰T细胞抗原间接识别途径,观察对同种异体移植心存活时间的影响。方法:用低剂量粒细胞-巨噬细胞集落刺激因子(GM-CSF)培养受者小鼠骨髓源性imDC,并在培养过程中加入供者可溶性抗原共同孵育,流式细胞术检测细胞表型,观察其在体外刺激自体T细胞增殖的能力,并于术前1周将约2.0×106个树突状细胞(DC)输入受者体内,观察其对同种异体移植心存活时间的影响。结果:受者DC可通过共同孵育的方式有效负载供者抗原,负载供者抗原的受者imDC在体外不能有效刺激自体T细胞活化增殖,将其于术前输入受者体内,移植心的存活时间由(7.2±1.7)天延长至(17.7±3.3)天。结论:术前输注负载供者抗原的受者imDC,可明显延长移植心的存活时间。