镍钛合金人工食管替代食管后的组织反应与损伤

背景：前期实验证实镍钛合金人工食管是一种可用于替代被切除食管段,重建食管通道的食管人工代用品。 目的：观察镍钛合金人工食管替代食管术后的组织反应及对邻近组织器官的损伤。 方法：切除8只小型香猪一段70 mm胸段食管,将镍钛合金人工食管两端分别套入远近端正常食管腔内约   10 mm,在食管与镍钛合金人工食管涤沦连接环作全层连续缝合吻合连接。术后第7天开始应用饮食调控方法调控脱管时间。分别在术后1,2,3,4个月各处死2只带管实验猪进行解剖,观察植入镍钛合金人工食管在新生食管形成过程中的组织反应和对紧密接触邻近组织器官的损伤。 结果与结论：各时间段植入镍钛合金人工食管原位停留支撑,未见胸内出血、气胸、脓胸、食管穿孔、吻合口瘘等术后邻近组织器官损伤并发症。实验动物带管进食半固体食物无进食困难(Bown'SⅡ级)。解剖所见：壁层胸膜与肺轻度膜状粘连,胸腔内无胸液,新生食管完全包裹人工食管,新生食管与邻近肺、主动脉器官组织轻度膜状粘连,未对邻近肺、主动脉及食管黏膜造成严重损伤,植入周期食管黏膜由食管残端向新生食管中间部再生延伸直到完全覆盖整条新生食管。新生食管组织学所见：镍钛合金人工食管替代食管植入周期的组织反应表现为无菌性炎症反应和异物反应,以术后1个月组织反应最为严重,随后逐渐减轻。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

人工组织神经移植物桥接修复缺损一月的大鼠坐骨神经

目的:用人工组织神经移植物桥接缺损1个月的大鼠坐骨神经,观察神经再生以及靶肌肉神经再支配的相关情况。方法:切除成年SD大鼠坐骨神经一段,造成1个月的神经缺损模型,用人工组织神经移植物进行桥接修复,3个月后进行神经及靶肌肉的观察。结果:术后3个月人工组织神经移植物组的复合肌动作电位、再生神经及腓肠肌的形态等和自体神经组接近,两组均明显优于缺损组。结论:人工组织神经移植物能在一定程度上修复缺损1个月的大鼠坐骨神经。     

食管支架材料选择及在老年食管癌的应用

目的：分析组织工程人工食管不同代替材料的应用及相容性,探讨其在老年食管癌置入后的疗效,寻求永久性的人工植入材料。 方法：以gene chip, protein chip, artificial neural network, gastrointestinal cancer, diagnosis”为英文检索词,“组织工程食管、人工食管,生物相容性,食管瘤,诊断”为中文检索词。由第一作者检索2000-01/2010-09PubMed数据及万方数据库,纳入与组织工程食管研究、人工食管置入后的生物相容性评价以及不同材料组织工程食管的实验分析相关的文献,排除重复性研究。保留中英文30篇文献进一步归纳总结。 结果：目前人工食管主要的并发症有吻合口瘘、狭窄、坏死、反流等。未来人工食管的研究方向主要集中在人工食管的构建理念以及构建材料的选择上,主要有以下几种观点：①选择理想的材料并构建成合适的形状。②体外培养-移植体内-诱导食管再生。③研制一种可精确调控的可生物降解的生物型人工食管,直接将其植人机体内,并以此为支撑物,在体内最终诱导、再生出新生的食管。 结论：组织工程食管的研究有朝着应用组织工程学方法构建与正常食管结构相类似的食管替代物,材料的选择从单一的生物惰性材料向可降解吸收的生物活性材料转变的多元化研究发展的趋势。     

大鼠食管空肠磁吻合实验研究

目的 以SD大鼠为模型探讨磁吻合技术在食管空肠侧侧吻合重建中的可行性。方法 10只SD大鼠,麻醉后取上腹部正中切口,将近端空肠提至食管下端附近,经口置入1枚圆形磁体至胃内,棉签推送磁体至近端空肠,此时经口置入另1枚圆形磁体至食管下端,空肠内磁体与食管内磁体自动相吸,建立食管空肠侧侧磁吻合模型。记录吻合操作时间,观察大鼠术后进食情况,记录磁体排出时间。1个月后处死动物,获取食管空肠侧侧吻合口标本,肉眼及组织学观察吻合口形成情况。结果 10只SD大鼠均成功完成了食管空肠侧侧吻合,整个手术操作过程顺利,术中未出现消化道损伤、出血等并发症,吻合操作时间(4.65±0.75)min;术后大鼠正常进食,无消化道梗阻表现;术后磁体排出时间为(11.30±1.77) d。所有大鼠术后1个月存活率为100%。术后1个月获取吻合口标本,肉眼观察可见吻合口形成良好,HE和Masson染色可见吻合口黏膜光滑平整,吻合口各层组织连续性良好。结论利用磁吻合技术可在食管与空肠之间建立良好的侧侧吻合,是对食管空肠磁吻合研究的有益探索。     

细菌纤维素修复兔颈段食管部分缺损的实验研究

利用纳米细菌纤维素膜修复兔颈段食管缺损,探讨细菌纤维素作为人工食管的可行性.制备15例兔颈段食壁长为1 cm,环1/3～1/2周径的全层食管壁缺损的动物模型,利用细菌纤维素膜修补食管缺损.术后观察兔的生存、生活状况,并于术后第8、12 w分别取材,对血液学及移植物行大体、组织学检查,并在术对前每例动物行X线检查.实验中...     

人工组织神经移植物对大鼠陈旧性坐骨神经缺损(60天)的修复作用

目的 观察人工组织神经移植物对陈旧性大鼠坐骨神经缺损的修复作用.方法 切除成年SD大鼠部分左侧坐骨神经,饲养60d形成陈旧性坐骨神经缺损后,以人工组织神经移植物修复缺损,同时设自体神经修复和不修复两对照组.修复术后3个月做神经-肌复合电位、腓肠肌湿重及再生神经形态学检测.结果 人工组织神经移植物修复组实验侧的运动神经传导速度、腓肠肌湿重、移植物远侧再生神经有髓神经纤维髓鞘厚度等结果与自体神经修复组相似.不修复对照组则未记录到神经-肌复合电位,未观察到再生神经纤维结构,腓肠肌湿重明显小于人工组织神经移植组和自体神经移植组.结论 人工组织神经移植物在一定程度上能修复缺损60d的大鼠坐骨神经.     

人工食管植入术后影像学检查的实验研究

目的探讨影像学检查方法在人工食管实验研究中的应用价值.方法对10只植入胸段记忆合金组合式人工食管的实验动物模型术后所进行X线平片和食管造影检查结果进行观察分析研究.结果 X线平片清晰显示胸内植入记忆合金组合式人工食管植入的位置原位固定>9个月3只;2～3月内脱管3只;>3个月内脱管4只;管体全部滑至胃内.食管造影连续摄片显示重度新生食管狭窄3只;轻度新生食管狭窄4只,同期介入安放食管支架2只.全组仅见1只发生吻合口细小瘘,无发现其它胸内并发症.结论①X线检查是进行人工食管动物实验研究简单且实用的检查方法.②食管造影连续摄片检查方法可为已建立植入人工食管的猪实验动物模型术后的观察研究及介入治疗提供多方面的支持帮助.     

聚乳酸-聚乙醇酸可降解支架构建组织工程食管

目的:观察人食管上皮细胞在聚乳酸-聚乙醇酸(PLGA)支架上的贴附和生长情况,利用组织工程技术培养工程化人工食管.方法:制作PLGA三维细胞支架;分离培养成人食管上皮细胞,体外扩增后种植到PLGA支架上.在体外和裸鼠体内分别培养食管上皮细胞-支架复合物,分期终止培养,进行组织学染色、扫描电镜、细胞角蛋白免疫组织化学检测.结果:体外培养显示,人食管上皮细胞在支架材料上贴附生长良好,长期培养仍保持食管上皮细胞特性,裸鼠体内培养4周后可形成食管黏膜样组织.结论:PLGA支架适合食管上皮细胞黏附生长,可作为食管组织工程的细胞载体.     

许旺细胞及小肠黏膜下层复合生长因子缓释微球修复周围神经缺损

背景：前期实验已初步证实许旺细胞复合小肠黏膜下层及碱性成纤维细胞生长因子构建的人工神经具有体外神经活性、趋化性。 目的：观察许旺细胞及小肠黏膜下层复合碱性成纤维细胞生长因子缓释微球修复周围神经缺损后神经传导的再通情况。 方法：制作SD大鼠坐骨神经缺损模型,随机分组：实验组以许旺细胞及小肠黏膜下层复合碱性成纤维细胞生长因子缓释微球修复,阳性对照组以许旺细胞及小肠黏膜下层复合游离碱性成纤维细胞生长因子修复,阴性对照组以许旺细胞及小肠黏膜下层修复,空白对照组以自体神经修复。 结果与结论：术后16周实验组再生神经纤维数目,DiI示踪标记的阳性神经元数量、S-100及神经细丝蛋白的阳性表达率、髓鞘及再生轴突的超微结构恢复、神经传导速度及复合动作电位的改善均优于阳性对照组与阴性对照组(P < 0.05)。表明许旺细胞复合小肠黏膜下层及碱性成纤维细胞生长因子缓释微球构建的人工神经可重建坐骨神经缺损后的神经传导通路。     

应用哑铃型人工食管对犬的食管重建的实验研究

采用硅橡胶及针织涤纶制成的哑铃型人工食管,将20只犬的中下段食管置换。对其通过功能及病理修复过程进行观察。由于哑铃状的特殊造型,能够实现较为长期固定,取得了全组动物平均存活509天,最长存活达7年零7个月。     

Intrathoracic esophageal replacement with a collagen sponge--silicone double layer tube: evaluation of omental-pedicle wrapping and prolonged placement of an inner stent

In a previous study, we replaced a 5 cm gap created in the canine intrathoracic esophagus with an artificial esophagus. However, although newly formed esophageal tissue subsequently bridged the gap, mild stenosis occurred, and this seemed to be caused by inadequate regeneration of the skeletal muscle. In the present study, we evaluated whether omental pedicle wrapping (OMPx) of the prosthesis could promote tissue regeneration and whether prolonged retention of the silicone tube within the prosthesis could prevent stenosis. A gap was created in 14 dogs, and the defect was repaired by our prosthesis. OMPx was performed in 5 of the 14 dogs (OMPx group) but not in the rest (control group). The silicone tube was retained for 4 weeks in the control group and for 8 weeks in the OMPx group. All of the dogs in the control group survived for more than 3 months, except for those that were killed. Four dogs in the OMPx group died within 3 months, one caused by perforation at 7 months. Only the thin epithelial and submucosal layer regenerated in the OMPx group. OMPx is not effective for promoting tissue regeneration, and prolonged retention of the silicone tube interrupts epithelial regeneration.     

Extension of bladder-based organ regeneration platform for tissue engineering of esophagus

Recent successes in regenerative medicine and tissue engineering of bladder and bladder-like neo-organs have leveraged regenerative constructs composed of a biodegradable scaffold seeded with a population of smooth muscle cells. We have shown that such smooth muscle cells are isolatable from adipose and other sources alternate to the primary organ. We hypothesize that this regenerative platform is not limited to regeneration of bladder and bladder-like neo-organs, but rather represents a foundational technology platform broadly applicable for regeneration of laminarly organized hollow organs. Using esophagus as an illustrative example in support of this hypothesis, we demonstrate that patch constructs composed of adipose-derived smooth muscle cells seeded on a biodegradable matrix catalyze complete regeneration of the esophageal wall in a rodent model of esophageal injury. By implication, such regenerative constructs may potentially be used to mediate the regeneration of any laminarly organized tubular organ.     

A neo-esophagus reconstructed by cultured human esophageal epithelial cells, smooth muscle cells, fibroblasts, and collagen

The scientists involved in this study attempted to develop an artificial esophagus constructed of autologous cells grown by cell culture methods on an extracellular matrix. An artificial esophagus consisting of human esophageal epithelial cells, dermal fibroblasts, and smooth muscle cells isolated from the aortic media, was attempted. The purpose of this study was to examine whether smooth muscle cells could be used in the transforming matrix. Human fibroblasts were embedded in Type I collagen superimposed on the collagen layer of smooth muscle cells. Next, human esophageal epithelial cells were cultured on the collagen layer of the fibroblasts. The resulting collagen sheets were cultured in vitro for 1 week, then transplanted on the latissimus dorsi muscles of athymic rats. The sheets were examined histologically at 1 and 2 weeks using hematoxylin eosin and immunologic stain methods (antiactin antibody). At the end of 2 weeks after transplantation, on microscopic observation of the collagen sheets, it appeared that the epithelial layer, the submucosal tissue layer, and the proper muscle layer had been reconstructed. Additionally, the authors successfully isolated smooth muscle cells from the media of the left gastric artery as a surgical specimen by explant cell culture. The ability to transform collagen sheets consisting of esophageal epithelial cells, fibroblasts, and smooth muscle cells from a surgical specimen into a luminal structure may enable clinical application of the artificial esophagus.     

螺旋CT在食源性食管异物诊断中的临床价值

目的:探讨螺旋CT在食源性食管异物诊断及临床治疗中的价值.方法:回顾分析25例经食管镜、手术证实的食道异物患者,比较MSCT薄层+三维重建:多平面重建(MPR)、最大密度投影(MIP)、容积荐现(VR)在临床诊断、治疗中价值.结果:经食管镜或手术证实的25例患者的食管异物为鸡鸭骨、鱼骨;MSCT检查均清楚显示异物,MS...     

磁压榨超微创技术建立兔获得性气管食管瘘动物模型

目的　探讨磁压榨超微创技术建立兔气管食管瘘（TEF）动物模型的可行性。 方法　10只新西兰兔麻醉后分别在颈段气管和食管内置入子母磁体,术后隔日X线拍片,观察子母磁体位置,当发现子母磁体脱离原位置进入消化道后3 d处死动物,观察TEF大体标本情况,并取瘘口组织行HE和Masson染色进行病理学观察。 结果　磁压榨超微创技术建立TEF平均操作时间（3.20±0.81）min,术后（6.90±1.14）d子母磁体脱落进入消化道,同时TEF形成,大体标本观察可见瘘口位于气管膜部与食管前壁之间,瘘口周围组织轻度粘连,组织病理学观察可见瘘口自气管膜部与食管前壁相通,与临床上获得性TEF病理学特征极为接近。 结论　磁压榨超微创技术可通过非手术方式建立兔获得性TEF,具有操作简单、创伤小、成功率高等优点,可谓一种理想的获得性TEF动物造模方法。     

Artificial esophagus with peristaltic movement

In this study, we have developed an artificial esophagus simulating peristaltic movement with the use of a nickel-titanium shape memory alloy (NiTi-SMA) actuator. Serial pairs of NiTi-SMAs were placed around a Gore-Tex vascular graft in a helical position such that they obliterated the lumen of the vessel when they contracted. In an animal experiment using a goat, the cervical esophagus was resected over a length of approximately 20 cm. The artificial esophagus was anastomosed with the remaining cervical esophagus. When a direct current of 500 mA at 5 V was applied to the NiTi-SMAs, the first pair of the NiTi-SMA contracted. The following pairs of the NiTi-SMAs contracted consecutively. The entire contraction of the artificial esophagus was similar to the esophageal peristaltic movement observed by x-ray examination in humans. The results showed the possibility that the artificial esophagus could function as an artificial esophagus having peristaltic movement.     

Successful repair of esophageal injury using an elastin based biomaterial patch

An esophageal injury with significant tissue loss is very difficult to repair. We conducted an in vivo study to test our elastin based acellular biomaterial patch to repair such defect. The patch was made from porcine aorta, by decellularization and sterilization. Collagen fibers were preserved to retain mechanical strength and enhance cellular in-growth. Ten domestic pigs underwent right thoracotomy. A 2 cm circular defect was made on the distal esophagus, excising half its circumference, and was repaired using the biomaterial patch and sutures. Soon after the procedure, the animals resumed oral feeding. They were followed for clinical status, weight gain, barium studies, and endoscopic studies, and were killed after 6 weeks to 4 months. All ten animals survived long term, with a procedure success rate of 100% (10 of 10). With the exception of one pneumothorax, no complications occurred, and all animals resumed oral feeding and gained weight. Endoscopic studies showed mucosal coverage by 6 weeks, with minimal stricture at the repair site. Excised specimens showed complete mucosal coverage with regeneration of all three layers. Our biomaterial patch can be used safely and reliably for repair of esophageal injury with significant tissue loss when repaired immediately as in our experiment.