β射线局部照射对冠状动脉弥漫性支架内再狭窄的疗效

目的：探讨β射线(^90Sr/^90Y)对冠状动脉(简称冠脉)弥漫性支架内再狭窄的疗效。方法:39例经皮冠脉介入术(PCI)及支架置入术后支架内再狭窄患者，随机分为支架内放射治疗组(治疗组)18例及单纯球囊组(对照组)21例。2组患者再狭窄病变先经充分球囊扩张，治疗组用Beta-Cath系统进行冠脉内放射治疗。术后随访9个月。结果:治疗组1例(5．6％)研究段血管再狭窄，对照组有8例(38．1％)再狭窄，两组间差异有显著性(P=0．006)。结论:β射线治疗冠脉弥漫性支架内再狭窄安全、有效、可行。     

自体脾组织移植的研究

目的　探索自体脾组织移植在严重脾外伤及门脉高压等全脾切除术病人中应用的可行性及价值。方法　将切除的脾脏 ,除去被膜 ,切成 1cm× 1cm× 0 .5cm的薄片 5 0块 ,移植在大网膜中间 ,用丝线缝合后固定于脾床。结果　经动物试验及术后B超 ,同位素扫描 (99m锝 )随访观察 ,移植的脾组织成活良好。血常规 ,血小板 ,IgM ,IgG ,补体C3,术后从低水平逐渐上升至正常。结论　全脾切除后自体脾组织移植能够成活并增生变大 ,而且能够维持一定的免疫功能 ,可预防严重的全身性感染发生。     

大鼠卵巢局部γ射线照射后的骨形态计量学改变

电离辐射对性腺的损伤已为人们所知 ,但对其产生的骨代谢远后效应研究甚少。早在 6 0年代 ,有人报道用 4 4Ｇｙ与30Ｇｙ的Ｘ射线局部照射大鼠卵巢 ,导致雌激素水平显著下降[1 ,2 ] 。笔者曾以 5 0ＧｙＸ射线局部照射大鼠卵巢[3] ,观察到卵巢辐射损伤后的骨吸收明显增强。在此基础上 ,笔者用5 0Ｇｙγ射线局部照射大鼠卵巢 ,90ｄ后进行血清雌二醇测定和骨组织病理学变化的观察 ,并与去势雌性大鼠和假手术大鼠进行了比较。一、材料和方法1 实验动物 :雌性ＳＤ大鼠 ,5月龄 ,体重 2 6 0～ 2 70ｇ ,由上海必凯实验动物公司提供 (清洁级 ,沪医实验…     

激光照射防治移植静脉再狭窄的实验研究

目的 观察激光照射对移植静脉血管平滑肌细胞（VSMC）增殖与凋亡的影响。探索激光疗法防治移植静脉远期再狭窄的可行性及作用机制。方法 建立兔颈外静脉颈总动脉移植模型。应用IECu-10铜蒸气激光器，输出波长510.6nm。功率密度500mW/cm^2，于移植静脉血管外照射1000s。术后4周，用免疫组织化学方法检测增殖细胞核抗原（PCNA），应用DNA片段末端标记法（TUNEL）标记凋亡细胞，HE，Masson及维多利亚蓝染色后，应用计算机图像分析系统检测移植静脉内膜，中膜增生情况。结果 术后4周，激光血管外照射的移植静脉与对照组相比，VSMC增殖率降低41.5%。细胞凋亡率增加40.9%。抑制了VSMC细胞增殖，促进细胞凋亡；移植静脉内膜和中膜厚度分别减少58.5%,18.0%，静脉内膜与中膜厚度比值（I/M）减少47.2%。结论 适当能量激光血管外照射可以抑制移植静脉血管平滑肌细胞增殖，促进移植静脉血管平滑肌细胞凋亡。使移植静脉内膜和中膜的增生减轻。有防治移植静脉远期再狭窄的作用。     

硬X线局部照射对猪皮肤创伤愈合影响的研究

目的：研究硬X射线局部照射对创伤愈合的影响规律。方法：采用大体观察、组织病理学、免疫组化、TUNEL和图像分析等方法，动态观察不同剂量硬X线局部照射后大鼠伤口愈合的过程。结果：观察发现皮肤放创复合伤的愈合时间与照射剂量存在着密切关系，相关性非常显著，r=0．985。照射后伤口组织胶原的合成降低、排列紊乱，肉芽组织的结构不规则。放创复合伤皮肤伤口成纤维细胞凋亡较单纯创伤组显著增加，伤口局部增殖细胞较单纯创伤组显著降低。结论：局部硬X线照射后，猪皮肤放创复合伤伤口愈合延迟，在20-50Gy之间时，延迟时间随照射剂量的增大而延长。     

5.21Gy软X射线局部照射伤口后组织细胞周期时相变化的研究

目的 研究软X射线局部照射后大鼠伤口组织细胞周期的时相变化。方法 PI染色，流式细胞术（FCM）检测细胞周期；BrdU掺入后采用SABC染色检测细胞增殖。结果 在伤后3－9d，对照侧G0／G1期细胞逐渐减少，S期细胞增加，9d时达到峰值；G2／M期细胞增加，15d时达到峰值。照射侧G0／G1期细胞增加，S期和G2／M期细胞减少。在伤后12－22d，照射侧S期细胞逐渐增加，22d时达到峰值，大量的细胞停留在S期。在整个愈合过程中，G2／M期细胞百分数均低于对照侧。BrdU掺入SABC染色阳性细胞主要为成纤维母细胞、血管内皮细胞以及平滑肌细胞。结论 5．21Gy软X射线局部照射后，细胞发生G1期阻滞和S期延长，G2／M转换障碍，细胞分裂增殖受抑，创伤愈合延迟与细胞周期的紊乱有关，G1期阻滞和S期延长越严重，愈合延长时间越长。     

超声检测犬自体静脉移植血管的实验研究

本实验应用超声对15只犬,24条股动脉自体静脉移植血管分二组(连续观察组和随机取样组)进行检查。二维超声检查显示连续观察组术后即刻和24h移植血管与宿主动脉的内径无明显差异(P>0.05)。移植血管中部内径大于近、远端吻合口(P<0.05),管壁呈不均匀增厚并经组织学证实。多普勒测定发现最大流速随移植时间不同有变化,术后即刻较慢,24h开始增快。移植血管远端血流量,搏动和阻力指数则无显著差异(P>0.05)。本实验表明尽管移植血管发生了组织改建、形态学和力学性质发生改变,但并未对流经该段血管的血流动力学产生明显影响,仍能维持远端动脉的血流。     

小鼠自体血离体照射回输提高机体抗辐射能力的实验研究

小鼠自体血离体照射回输的实验研究,是以辐射抗辐射,在观察对ＢＡＬＢ／Ｃ小鼠小肠粘膜急性放射损伤防护及对ＢＡＬＢ／Ｃ小鼠的骨髓急性放射损伤防护作用方面,均取得了预期疗效,现报道如下。一、材料和方法１－实验动物：ＢＡＬＢ／Ｃ小鼠,雌性,体重２２～２５ｇ,由中国医学科学院肿瘤研究所动物实验室提供〔动物合格证号为（京动字）８９１０Ｍ０４７〕。２－照射条件：实验采用Ｖａｒｉａｎ直线加速器,６ＭＶＸ射线,ＳＳＤ１００ｃｍ。照射前由物理室技术人员进行剂量核准,吸收剂量率为２５０ｃＧｙ／ｍｉｎ。（１）动物照射：…     

Incidence and classification of neointimal proliferation and in-stent restenosis in post-stenting patients at 1-year interval: Findings from non-invasive coronary computed tomography angiography

Objectives

To evaluate the incidence of coronary in-stent restenosis (ISR) and neointimal proliferation by coronary CT angiography (CCTA) at 1-year follow-up in asymptomatic patients.

Methods

234 patients (mean age: 67 ± 10.2 years, range 39–88 years, 180 males and 54 females) with 379 stents were prospectively enrolled in this study. Binary ISR was classified by CCTA into 4 types using Mehran classification. Neointimal proliferation was similarly classified into focal and diffuse types. All patients with CCTA-revealed ISR or neointimal proliferation underwent further invasive coronary angiography (ICA) for validation. Fisher's exact test was used for comparison.

Results

ICA revealed patent stents with neointimal proliferation in 39 patients (16.7%, 39/234) and binary ISR in 23 patients (9.8%, 23/234). Lesion-based analysis showed 12 type I ISR lesions, 4 type II ISR lesions, 1 type III ISR lesion and 7 type IV ISR lesions. Among cases with neointimal proliferation, 27 lesions were classified as focal type whereas 13 lesions were classified as diffuse type. Patients with diabetes mellitus were associated with higher incidence of CCTA-revealed neointimal proliferation (21/77 vs. 18/157, p = 0.002) as well as ISR (12/77 vs. 11/157, p = 0.038), compared to patients without diabetes. CCTA was found to have good diagnostic performance for neointimal proliferation and ISR detection as well as classification, with an overall accuracy of 84.4% (54/64).

Conclusions

Silent ISR as well as neointimal proliferation is not uncommon findings in asymptomatic post-stenting patients at 1-year interval, as revealed by CCTA. Patients with diabetes are prone to have higher incidence of neointimal proliferation.     

Cryoplasty for the Prevention of Arterial Restenosis

Restenosis after percutaneous transluminal angioplasty remains the limiting factor for the long-term benefit of endovascular therapies of peripheral arterial occlusive disease. Despite a variety of modifications and adjuncts to angioplasty such as bare metal stents, covered stents, and drug-eluting stents as well as a number of new technologies like laser angioplasty and cutting balloon angioplasty, restenosis rates have not been significantly affected and remain inferior to those for surgery for long lesions in the femoropopliteal segment. Cryoplasty, which combines balloon angioplasty with the application of cryothermal energy to the vessel wall, was suggested as a promising approach to prevent the formation of neointimal hyperplasia after angioplasty procedures. This review discusses the basic principles of cryoplasty, summarizes the current data on restenosis rates after cryoplasty treatment, and evaluates cryoplasty as a new treatment method to solve the problems associated with restenosis development. The results of the clinical studies suggest that cryoplasty is a feasible and safe technique in the treatment of femoropopliteal disease, however, they have failed to prove any superiority of cryoplasty over conventional angioplasty.     

Evaluation of the small intestinal submucosa covered stent in preventing restenosis after percutaneous transluminal angioplasty in the swine

Objective

To compare the performance of small intestinal submucosa (SIS)-covered endografts (SCEs) to bare nitinol stents (BSs) in injured swine iliac arteries.

Materials and methods

Twenty-eight nitinol stents were used: 14 externally SCEs and 14 BSs. Devices were implanted in each side of balloon-injured external iliac arteries of 14 swine via carotid approach. Arteriograms were obtained before and after implantation and before animal sacrifice at 4, 8, and 12 weeks. Histopathological and electron microscopy studies of explanted specimens were performed.

Results

Implantation of all SCEs and BSs was technically successful, but one SCE and one BS were obstructed at 8 weeks after implantation. At sacrifice, the other 26 stents were patent, with angiogram showing no significant different luminal narrowing between SCEs and BSs. Proliferating cell nuclear antigen (PCNA) immunohistochemistry examination revealed that the percentage of PCNA(+) cells were lower in SCEs (p < 0.05). Additionally, histomorphological analysis indicated that the neointima area and percentage of narrowing area were greater in SCEs, but there was no statistical significance. Greater endothelial cell count in SCEs than in BSs per visual field at 4000 times magnification by scanning electron microscope (p < 0.05).

Conclusion

Compared to BSs, no definite decrease of neointima and restenosis was found in SCEs in the present study. However, it is effective in promoting endothelial regeneration and strengthening endothelial function.     

曲尼司特对兔髂动脉损伤后内膜增殖及血管重构的影响

目的　探讨曲尼司持对兔髂动脉球囊损伤后内膜增殖及血管重构的影响。方法　 2 4只新西兰大白兔随机分为假手术组、对照组和用药组。用球囊导管对用药组和对照组兔行髂动脉损伤。用药组于术前 3d开始用曲尼司特 (每天 30 0mg/kg) ,术后 2 8d取病变血管苏木精 伊红和弹力纤维染色并免疫组化检查 ,以计算机图像分析血管内膜、中膜厚度、管腔面积、平均动脉面积 (外弹力膜内横截面积 ,EEL)的变化 ,计算增殖细胞核抗原 (PCNA)增殖指数 (PI)。结果　曲尼司特显著减少内膜厚度 ,增加血管腔面积和平均动脉面积 ,对中膜厚度无明显影响。曲尼司特使内膜PCNA阳性细胞百分比降低。结论　曲尼司特能抑制兔髂动脉球囊损伤后内膜增殖 ,促进代偿性血管扩张。其抑制内膜增生可能与抑制血管平滑肌细胞增殖有关     

Aneurysm formation in distal saphenous vein bypass grafts as a cause of graft failure

Aneurysms of a reversed saphenous vein femoropopliteal bypass graft developed in two patients. In both patients, the aneurysm led to thrombosis and occlusion of the graft. One graft was reopened by intraarterial thrombolysis followed by local graft revision; the other required complete regrafting. This uncommon cause of graft occlusion should be considered before thrombolysis.     

Short vein grafts in limb-saving arterial reconstructions

In the management of limb-threatening infrainguinal arteriosclerosis, the short vein graft is a feature of distal-origin bypass procedures from the superficial femoral and popliteal arteries to more distal arteries. These procedures, which can only be performed in selected patients, have patency rates equivalent to those of comparable bypasses from the common femoral artery. Other advantages include the increased availability of the shorter vein graft segment that is required. Two newer operations that use short vein grafts are tibio-tibial bypasses and bypasses to isolated segments of infrapopliteal arteries. The authors' initial experience with these two procedures includes encouraging patency and limb salvage rates for periods up to 2 years in patients for whom there was no other therapeutic option short of amputation.     

In vivo vascular engineering of vein grafts: directed migration of smooth muscle cells by perivascular release of elastase limits neointimal proliferation

PURPOSE: Saphenous vein bypass grafting for coronary revascularization procedures remains limited by accelerated neointima formation. It was hypothesized that creation of a modified chemotactic gradient in vivo could guide migration of smooth muscle cells (SMCs) peripherally instead of in a luminal direction and reduce intimal hyperplasia during vein graft arterialization. MATERIALS AND METHODS: Surgical bypass vein grafting to femoral arteries was performed in adult male New Zealand White rabbits (n = 8 per treatment group; five for 7 d and three for 28 d). Controlled-release microspheres delivering elastase or buffered polymer only were administered perivascularly at the vein graft site. At 7 days, five vein grafts per group were harvested and cross-sections were immunostained with anti-proliferating cell nuclear antigen (PCNA) to determine the number and distribution of proliferating SMCs. At 28 days, three vein grafts per group were harvested and intima-to-media (I/M) ratios were calculated after staining with Verhoeff von Gieson-Masson trichrome stain. RESULTS: Significant early outward-directed elastin degradation resulted from elastase treatment. Concurrently, proliferating SMCs migrated peripherally. PCNA(+) cells in the outer half of the wall increased 2.37 fold compared to procedural controls (P <.0001). Directional shifts in SMC migration underlie these results because overall SMC proliferation was not significantly different. At 28 days after vein graft surgery, a 38% reduction (P =.0008) in neointima was observed relative to procedural controls. CONCLUSION: Directional guidance of SMC responses through perivascular elastase release achieves favorable vein graft remodeling characteristics, including limited neointima development. This represents practical evidence that SMC migration can be directionally guided in vivo in a vein graft model and that plaque progression can be prevented by redistributing elastin without decreasing functional vein graft wall stability.     

应用冠脉血管内超声评价药物涂层支架置放后再狭窄及血管内膜增生

目的应用冠脉内超声测量支架置入6个月后内膜增生厚度,准确比较不同支架再狭窄率。方法选择57例药物洗脱支架(DES)置入术后4～8(6±2)个月同意复查冠脉造影及冠脉血管内超声的冠心病(CHD)住院患者,分为Cypher支架组(25例)和Firebird支架组(32例),及同期491例植入金属裸支架(BMS)CHD患者,测量支架置入后6个月时的内膜增生并进行比较。结果冠脉造影显示DES发生再狭窄Cypher组11例,Firebird组10例,裸支架组25例。再狭窄率分别为8.4%,8.9%和10.0%。DES两组差异无统计学意义,裸支架组与Cypher组及Firebird组相比较差异有显著性。冠脉内超声检查结果显示DES组中Cypher支架新生内膜面积为(1.11±0.89)mm2,支架再狭窄率(9.0±0.1)%;Firebird组为(1.13±0.08)mm2,支架再狭窄率(10.0±0.2)%。DES两组间比较差异无统计学意义。裸支架组支架新生内膜面积为(1.44±0.04)mm2,再狭窄率为(21.0±0.1)%,与DES两组比较,有显著的统计学差异(P<0.05)。支架两端的节段狭窄率DES组中近端的节段狭窄Cypher组(0.43±0.25)%与Firebird组(0.40±0.15)%都显著高于裸金属支架组(0.29±0.13)%(P<0.05)。远端的节段狭窄率,三组比较差异无统计学意义。结论应用冠脉内超声评价支架内再狭窄准确度优于冠脉造影。DES降低支架内再狭窄率明显优于裸金属支架,防止支架节段狭窄,裸金属支架可能有优势。     

激光血管成形术后血管的形态学变化

用腹主动脉内膜球囊损伤造成狭窄≥50％的日本大耳白兔50只进行激光血管成形术(LA),术后3、7、14、21、28、35、42、49、56和63天血管取材切片作病理变化分析。结果:LA后14天,血管平滑肌细胞(SMC)出现增殖,动脉中层SMC向内层迁移;LA后28天,内膜层SMC增殖最为明显,并导致血管再狭窄;内膜层SMC表型与合成型SMC相似;LA后35天,内膜层增厚速度降低。结论:实验性LA后SMC增殖反应呈一动态过程,与球囊血管成形术后再狭窄的病理变化大致相同,故本实验模型适于LA后血管再狭窄机制的研究。