改性壳聚糖防粘连膜防止心肌梗死模型兔心脏与周围组织粘连

目的 观察改性壳聚糖防粘连膜对心肌梗死兔心脏与周围组织粘连程度的影响.方法 25只日本长耳白兔,开胸结扎冠状动脉制备心肌梗死模型,随机分为对照组(A组)和改性壳聚糖防粘连膜组(B组),A组正常关胸,B组关胸前在心脏和胸壁间置入改性壳聚糖防粘连膜.每组造模型成功各11只.术后3个月A组存活8只、B组存活9只.分别行在体磁共振电影和二次开胸,分级评价粘连程度.采用Wilcoxon秩和检验.结果 磁共振电影评价粘连程度,A组轻度粘连、中度粘连、重度粘连分别为2只、2只、4只;B组分别为7只、2只、0只.差异有统计学意义(P<0.05).开胸评价粘连程度,A组无粘连、轻度粘连、中度粘连、重度粘连分别为1、1、2、4只;B组分别为3、4、2、0只.差异有统计学意义(P<0.05).结论 改性壳聚糖防粘连膜可以减轻心肌梗死模型兔心脏与周围组织粘连.     

改性壳聚糖防粘连膜防止心肌梗死模型兔心脏与周围组织粘连

目的 观察改性壳聚糖防粘连膜对心肌梗死兔心脏与周围组织粘连程度的影响.方法 25只日本长耳白兔,开胸结扎冠状动脉制备心肌梗死模型,随机分为对照组(A组)和改性壳聚糖防粘连膜组(B组),A组正常关胸,B组关胸前在心脏和胸壁间置入改性壳聚糖防粘连膜.每组造模型成功各11只.术后3个月A组存活8只、B组存活9只.分别行在体磁共振电影和二次开胸,分级评价粘连程度.采用Wilcoxon秩和检验.结果 磁共振电影评价粘连程度,A组轻度粘连、中度粘连、重度粘连分别为2只、2只、4只;B组分别为7只、2只、0只.差异有统计学意义(P<0.05).开胸评价粘连程度,A组无粘连、轻度粘连、中度粘连、重度粘连分别为1、1、2、4只;B组分别为3、4、2、0只.差异有统计学意义(P<0.05).结论 改性壳聚糖防粘连膜可以减轻心肌梗死模型兔心脏与周围组织粘连.     

新型壳聚糖衍生物预防椎板切除术后硬膜外粘连的实验研究

目的:探讨一种新型壳聚楮衍生物--羟丁基壳聚糖对椎板切除术后硬膜外粘连的预防作用.方法:36只SD大鼠随机分为3组,2%羟丁基壳聚糖组(A组)、3%羟丁基壳聚糖组(B组)及对照组(C组),每组12只.三组大鼠行L2椎板切除术后.A、B组于硬脊膜外分别注入2ml浓度为2%、3%羟丁基壳聚糖溶液,C组旷置,然后缝合切口.术后6周取材,大体观察硬膜外粘连情况,进行Rydell分级;行免疫组织化学检测,计算羟脯氨酸(hydroxyproline,Hyp)含量;切片行HE染色,观察硬膜外瘢痕增生情况,并行成纤维细胞计数.结果:术后6周A组及B组硬膜外粘连程度均较C组轻,Rvdell评分差异显著(P＜0.05),而A、B组之间无显著性差异(P＞0.05);三组硬膜外瘢痕组织中Hyp含量分别为0.284±0.065μg/mg、0.302±0.109μg/mg、0.963±0.188μg/mg,A、B组含量均较C组少,差异显著(P＜0.05),而A、B组之间无显著性差异(P＞0.05);组织学观察见A组及B组与C组比较硬脊膜外胶原增生较少,瘢痕组织结构疏松,但三组成纤维细胞计数无显著性差异(P＞0.05).结论:羟丁基壳聚糖能够有效阻隔大鼠硬膜外瘢痕组织,明显减少胶原组织增生,具有良好的预防硬膜外粘连的作用,有望成为一种新型防粘连生物医学材料.     

化学改性壳聚糖膜预防不同类型腹膜粘连的实验研究

目的对比研究化学改性壳聚糖膜对四种不同原因所致的大鼠腹膜粘连的预防作用。方法将壳聚糖行化学改性，制成厚60μm的膜消毒后备用。SD大鼠200只，随机分成假手术对照组（A组）、创伤致粘连组（B组）、滑石粉致粘连组（C组）、结扎血管致粘连组（D组）及感染致粘连组（E组）。各组分别用相应的方法来处理大鼠蚓突盲端．再将每组大鼠分成对照组和实验组．对照组大鼠直接关腹，实验组用凝胶化改性壳聚糖膜覆盖蚓突盲端浆膜面．然后关腹。处理后2周和4周后打开腹腔，以Bhatia分级法评定蚓突盲端的粘连程度，并对盲端组织行羟脯胺酸（hydroxyproline，OHP）、组织型纤溶酶原激活剂tissue—type plasminogen activatior，t—PA）和纤溶酶原激活物抑制因子（plasminogen activator inhibitor，PAI）水平测定，对腹腔液行t—PA、PAI测定。结果①粘连程度和OHP水平：术后2周和4周，B、D、E组中实验组的粘连程度、OHP水平均分别显著低于对照组（P〈0．05），而A、C组中的实验组和对照组间差异均无统计学意义（P〉0．05）；②t-PA、PAI水平：术后2周和4周，A组、C组和D组的蚓突组织和腹腔液t—PA、PAI水平．实验组和对照组间差异均无统计学意义（P〉0．05）；B组、E组中实验组t—PA水平均显著高于对照组（P〈0．05），而PAI水平则显著低于对照组（P〈0．05）。结论化学改性壳聚糖膜时创伤、缺血及感染所致的腹膜粘连有明显的预防作用，而对滑石粉所致的腹膜粘连则作用不明显；对不同原因所致的腹膜粘连．可以用来准确衡量组织粘连程度的指标也不尽相同。     

羟丁基壳聚糖预防大鼠腹腔粘连的实验研究

目的 探讨羟丁基壳聚糖对大鼠术后腹腔粘连的预防作用.方法 清洁级SD大鼠90只,雌雄各半,体重250～280 g,随机分为3组(n=30).采用纱布摩擦盲肠浆膜面制作腹腔粘连动物模型后,A、B组分别于盲肠表面喷涂2 mL浓度为2%的羟丁基壳聚糖溶液及透明质酸钠凝胶,C组旷置30 s后关腹.术后观察大鼠一般情况,术后2、4剧每组各取15只大鼠,行大体观察及组织学观察,双盲法行粘连程度分级.术后4周A、C组透射电镜观察创伤处盲肠壁的超微结构.结果 术后人鼠均存活至实验完成.术后2周,A、B组腹腔粘连程度较轻,纤维结缔组织及胶原增生较少,C组腹腔粘连较重,纤维结缔组织大量增生;根据Nair五级分级标准及组织学观察分级A、B组与C组差异有统计学意义(P＜0.05),A、B组间差异无统计学意义(P＞0.05).术后4周,A组粘连程度轻,纤维结缔组织及胶原增生少,C组腹腔粘连严重,纤维结缔组织及胶原大量增生,B组介于两者之间,3组分级差异有统计学意义(P＜0.05).透射电镜观察结果显示:A组成纤维细胞不活跃,胶原纤维较纤细,排列稀疏;C组成纤维细胞活跃,胶原纤维致密、紊乱.结论 羟丁基壳聚糖可显著减少大鼠腹腔术后纤维结缔组织增生,明显抑制成纤维细胞的活性,具有长时间预防腹腔粘连的作用.     

透明质酸衍生物Seprafilm防粘连薄膜防止肌腱粘连的实验研究

目的观察透明质酸衍生物Seprafilm防粘连薄膜在急性肌腱损伤后防止肌腱粘连的有效性。方法 4月龄中国白兔18只,雌雄各半,体重2.0～2.5kg。于双侧后足第2、3足趾制作屈肌腱损伤模型。根据处理方法不同随机分为4组(n=18),右侧第2趾应用Seprafilm防粘连薄膜包裹肌腱(A组),右侧第3趾应用聚乳酸可吸收防粘连膜包裹损伤段后缝线缝合固定(B组),左侧第2趾将透明质酸钠凝胶涂布于损伤肌腱段的腱周(C组),左侧第3趾不作任何处理作为对照(D组)。术后观察实验动物一般情况,于1、2、4周取材测量远趾间关节活动度,并行大体及组织学观察,对粘连程度分级。结果所有实验动物均存活至实验完成。各时间点A组远趾间关节活动度与B组比较,差异均无统计学意义(P>0.05);除术后1周外均优于C、D组(P<0.05)。大体观察及组织学观察粘连分级一致,术后1周时各组间比较差异均无统计学意义(P>0.05);2、4周时,A组与B组比较差异无统计学意义(P>0.05),但粘连程度较C、D组轻,比较差异均有统计学意义(P<0.05)。结论透明质酸衍生物Seprafilm防粘连薄膜可防止兔急性肌腱损伤后的肌腱粘连,并能改善关节功能。     

壳聚糖凝胶对大鼠腹膜粘连的预防作用

目的:探讨壳聚糖凝胶对三种不同原因所致的大鼠腹膜粘连的预防作用.方法:144只SD大鼠,随机分成创伤致粘连组(A组)、滑石粉致粘连组(B组)及结扎血管致粘连组(C组).各组分别用相应的致粘连方法来处理大鼠蚓突盲端,再将每组大鼠分成对照组和实验组,对照组大鼠直接关腹,实验组用壳聚糖凝胶均匀涂布于经处理的蚓突浆膜面,然后关腹.处理后2 w、4 w再次打开腹腔,肉眼评定蚓突盲端同其周围组织的粘连程度,并取蚓突盲端组织行病理组织学检查.结果:①粘连评定:术后2 w和4 w,A组和C组中实验组的粘连程度均分别显著低于对照组(P<0.05或P<0.01),而B组中的实验组和对照组间均无明显差异(P>0.05).②病理改变:A组处理侧浆膜面以纤维组织增生为主,而C组蚓突全层均有纤维组织增生,以浆膜层为重.B组处理侧浆膜面有大量异物巨细胞反应及肉芽肿形成,并伴有程度不同的纤维组织增生.结论:壳聚糖凝胶对创伤及缺血所致的腹膜粘连有明显的预防作用,而对异物所致的腹膜粘连作用则不明显.     

凝胶化改性壳聚糖膜预防腹膜粘连的效果研究

目的对比研究凝胶化改性壳聚糖膜和透明质酸钠对腹膜粘连的预防作用。方法SD大鼠80只,随机分成4组：假手术对照组（A组）,生理盐水对照组（B组）,凝胶化改性壳聚糖膜组（C组）,透明质酸钠组（D组）。利用大鼠蚓突盲端制作创伤性腹膜粘连模型,然后每组分别用相应的方法处理创面,处理后第2周和第4周打开腹腔,以Bhada分级法评定蚓突盲端的粘连程度,并对盲端组织行羟脯胺酸（OHP）水平测定和病理组织学检查。结果术后第2周和第4周,C,D组的粘连程度均显著轻于B组（P=0．001～0．013）,OHP水平显著低于B组（P=0．037～P〈0．001）;C组和D组比较,粘连程度分级的差异两组间无显著性意义（P〉0．05）,但OHP含量C组显著低于D组（P=0．005,0．002）。病理学检查：A组所有大鼠蚓突组织无明显的病理改变,B组术后第2周时处理侧浆膜面有明显的炎症细胞浸润和纤维组织增生,术后第4周局部主要以纤维组织增生为主;相应的病理改变C,D组较B组明显减轻,C组的病理改变又明显轻于D组。结论凝胶化改性壳聚糖膜具有明显的抗腹膜粘连作用,且此作用较透明质酸钠具有优势。     

Zn2+改性羧甲基纤维素预防术后腹膜粘连

目的 观察Zn2+改性羧甲基纤维素( Zn2+ -SCMC)对术后腹腔粘连的预防作用.方法 将90只大鼠随机分为A、B、C3组,每组各30只.先行均制作肠粘连模型,取A组腹腔内不放药物,B、C组于腹腔内损伤部位分别置入3ml、浓度3％的羧甲基纤维素(SCMC)及3ml、浓度3％的Zn2+ -SCMC,术后10d处死大鼠,观察各组腹腔粘连情况.结果 大鼠肠壁组织病理:A组纤维细胞增生明显,胶原纤维排列致密;B组纤维细胞增生较明显,胶原纤维排列略密;C组纤维细胞增生较轻,胶原纤维排列较疏松.术后10d腹腔内粘连情况:C组腹腔内轻微粘连,粘连发生率44.8％,B组中度粘连,粘连发生率80.0％,A组广泛粘连,致密,粘连发生率100.0％.A组Ⅲ～Ⅳ级粘连最多为17只,B组Ⅱ级粘连最多12只,C组0级粘连最多16只,C组粘连分级较B组、A组明显减轻,差异有统计学意义(P＜0.01).结论 Zn2+ -SCMC能明显减轻术后腹腔粘连程度,其作用优于SCMC.     

几丁糖改性膜预防椎板切除术后硬膜外粘连

目的　探讨预防椎板切除术后硬膜外粘连的有效材料和方法。方法　新西兰兔 2 4只 ,行L2 、L4及L6椎板切除术 ,造成 8mm× 5mm硬脊膜裸露区 ,共 72个节段 ,随机分为 3组 ,分别植入不同的材料 :A组植入几丁糖改性膜 ;B组植入透明质酸钠 ;C组用生理盐水对照。术后 2、4、8、12周处死动物取材 ,进行瘢痕形成情况的肉眼观察和组织学观察、硬膜外粘连等级评定及图像分析等。结果　C组硬膜外形成致密粘连 ,B组部分粘连 ,A组无明显粘连。结论　几丁糖改性膜对硬膜外粘连有明显的预防作用 ,其作为椎板切除术后的内植物值得做进一步研究     

Reduction in postoperative adhesion formation and re-formation after an abdominal operation with the use of N, O - carboxymethyl chitosan

BACKGROUND: Postoperative adhesions have proven to be intractable complications after abdominal operations. This study assessed the efficacy of N, O - carboxymethyl chitosan (NOCC) to limit adhesion formation and re-formation in a rabbit abdominal surgery model. METHODS: In study 1 (adhesion formation), injuries to the large bowel, cecum, and abdominal sidewall were generated in rabbits. The rabbits (10/group) were randomly assigned to 1 of 5 treatment groups: Group A received no NOCC treatment; in group B, NOCC gel was applied directly to the injured site and NOCC solution was applied throughout the abdominal cavity; in group C, NOCC gel was applied near the injured site and NOCC solution was applied as above; in group D, NOCC gel was applied distant to the injury and NOCC solution was applied as above; in group E, a mixture of NOCC gel and solution was applied at the injured site. Adhesions were evaluated 14 days later. In study 2 (adhesion re-formation), adhesions were generated as above but were then lysed by careful dissection. After adhesiolysis, the rabbits (9/group) were treated with NOCC gel and solution at the site of adhesiolysis or left untreated. Adhesion re-formation was assessed 14 days later. In study 3 (mechanism of action), sterile tissue culture plates were coated with NOCC and adhesion of cultured, radiolabeled murine fibroblasts to the plates was assessed. RESULTS: In study 1, animals treated with NOCC gel and solution showed reduced adhesion formation (P<.01). NOCC gel was equally efficacious if applied on the site of injury or near the site of injury but less efficacious if applied at a site distant to the injury. In study 2, animals treated with NOCC gel and solution showed less adhesion re-formation compared with the untreated control animals (P<.01). In study 3, murine fibroblasts did not adhere to NOCC-coated tissue culture plates. CONCLUSIONS: NOCC gel and solution can reduce adhesion formation and re-formation in this rabbit model. The inability of fibroblasts to adhere to NOCC solution-coated surfaces suggests that NOCC may act as a biophysical barrier.     

医用几丁糖预防宫腔再粘连的临床分析

目的 探讨医用几丁糖在宫腔粘连分离术后预防宫腔再粘连的临床效果.方法 2011年3月-2013年4月宫腔镜下宫腔粘连分离术112例,根据术后防粘连的方法不同分为研究组和对照组：研究组61例,术后宫腔内放置医用几丁糖2.5 ml及元宫环1枚,术后联合人工周期治疗（戊酸雌二醇3 mg每12 h口服1次,共21 d,最后10 d加用安宫黄体酮6 mg,1次/d,口服）;对照组51例,术后宫腔内放置元宫环1枚,术后用药同研究组.比较2组术后再粘连发生率.结果 2组轻度粘连患者术后均未见宫腔粘连复发.中度宫腔粘连患者分离术后复发率研究组13.9%（5/36）显著低于对照组36.7%（11/30）（Z=-2.134,P=0.033）.重度宫腔粘连患者分离术后复发率研究组66.7%（6/9）与对照组88.9%（8/9）无统计学差异（Z=-1.102,P=0.270）.重度粘连患者二次宫腔镜下粘连分离术后宫腔镜检查,研究组2例存在粘连,对照组7例,有统计学差异（Z=-2.017,P=0.044）.结论医用几丁糖能有效预防中、重度宫腔粘连患者的术后复发.     

Postoperative pericardial adhesion prevention using Carbylan-SX in a rabbit model

INTRODUCTION: The presence of dense adhesions within the pericardial space complicates reoperative cardiac surgery. Prior attempts to reduce adhesion formation after primary cardiac surgery using medications or biomaterials have had variable success. Carbylan-SX (Carbylan Biosurgery Inc., Palo Alto, CA) is a hyaluronan-based biomaterial, which has been shown to be effective at reducing adhesions in a nonthoracic rat model. This study evaluates whether Carbylan-SX can effectively reduce postoperative adhesions within the pericardial cavity. METHODS: Thirty-eight New Zealand white rabbits underwent a left lateral thoracotomy. A pericardiotomy was made and epicardial adhesions were induced on the anterior surface of the heart using a Dremel device (Racine, WI). The rabbits were divided into four groups: controls with abrasions only receiving no treatment (n=10), Carbylan-SX films (n=10), Carbylan-SX aerosolized hydrogel (n=10), and Seprafilm (n=8). The pericardial sac and chest were subsequently closed. Rabbits were sacrificed at a mean of 15 days. For histological analysis, each heart was divided into 12 separate 1 mm sections. Computer imaging software was used to measure the adhesion thickness and the mean of 12 random measurements for each animal was recorded and statistical analysis performed. RESULTS: Histological analysis revealed all treatment groups to be significantly better than the control (2159 mum thickness, P<0.0001) at preventing adhesions. The Carbylan-SX film and Carbylan-SX aerosolized hydrogel both proved to be better at preventing adhesions than Seprafilm (Genzyme Corp., Cambridge, MA) with an average adhesion thickness of 454 and 577 microm, respectively, compared with 1319 microm for Seprafilm (P<0.0001 and P<0.0005, respectively). The Carbylan-SX film and Carbylan-SX aerosolized hydrogel were equally effective at preventing adhesion formation. CONCLUSION: Carbylan-SX film and Carbylan-SX aerosolized crosslinkable hydrogel are equally effective methods of reducing postoperative pericardial adhesions within the pericardial cavity. Both the Carbylan-SX film and aerosolized hydrogel showed a significantly greater reduction in adhesions than Seprafilm. Clinical application of Carbylan-SX could have significant therapeutic implications in the future.     

Improved myocardial function after transmyocardial laser revascularization according to cine magnetic resonance in a porcine model

OBJECTIVE: This study was undertaken to demonstrate that transmyocardial laser revascularization of hypoperfused myocardium improves regional and global myocardial function. METHODS: Cine magnetic resonance imaging was used to monitor regional wall thickening (in millimeters) and cardiac output (in milliliters per kilogram per minute). Cine magnetic resonance imaging was performed before and 8 weeks after transmyocardial laser revascularization was applied to the hypoperfused lateral wall of the left ventricle (target area) in a porcine model (n = 9, transmyocardial laser revascularization group). A second group of animals was left untreated (n = 8, control group). RESULTS: Regional wall thickening in the target area improved after transmyocardial laser revascularization (0.7 +/- 0.3 mm to 3.7 +/- 1.9 mm, P <.02) and was significantly higher (P <.01) after transmyocardial laser revascularization than in the control group, in which it did not improve (0.5 +/- 0.6 mm to 0.5 +/- 1.2 mm). Accordingly, cardiac output and microsphere-derived myocardial blood flows were significantly higher than in the control group (P <.01), and the amount of triphenyltetrazolium chloride-stained myocardium was lower (P <.01). CONCLUSION: Cine magnetic resonance imaging demonstrates improved global and regional myocardial function after transmyocardial laser revascularization in a porcine model.     

Prevention of postoperative pericardial adhesions in children with hypoplastic left heart syndrome

Reoperations for congenital cardiac defects are associated with an increased surgical risk due to adhesions. We compared the capability of a polytetrafluoroethylene (PTFE) membrane, synthetic polyethyleneglycol hydrogel (PEG), and a combination of them to prevent postoperative pericardial adhesions in patients with hypoplastic left heart syndrome (HLHS). Eighteen consecutive patients with HLHS were included. At the end of the Norwood I operation the cranial and the caudal half of the heart of each patient was randomized to receive a PTFE membrane, a synthetic PEG, a combination of them, or no treatment (control). Tenacity and density of adhesions, epicardial visibility, and adhesions between the heart and the sternum were analyzed semiquantitatively at a subsequent bidirectional Glenn operation. The PTFE membrane significantly decreased adhesion formation between the heart and the sternum (P<0.001). However, the PTFE membrane, with or without synthetic PEG, impaired epicardial visibility (P<0.05) when compared to synthetic PEG or controls. Synthetic PEG alone did not significantly reduce the formation of pericardial adhesions. Tenacity and density of adhesions were not affected by any of the treatment modalities. The PTFE membrane significantly decreases postoperative adhesions between the heart and the sternum, but impairs epicardial visibility. Synthetic PEG does not prevent formation of pericardial adhesions.     

Prevention of pericardial adhesions with N-O carboxymethylchitosan in the rabbit model.

The presence of mediastinal adhesions significantly increases the morbidity and mortality of reoperative cardiac surgical procedures. Previous investigations have reported on the therapeutic utility of topical hydrogels in reducing the formation of postsurgical adhesions. The goal of the present study is to evaluate the ability of N-O carboxymethylchitosan (a glycosaminoglycan hydrogel derivative) to reduce the formation ofpostsurgical pericardial adhesions in a large-animal model. Sixteen adult New Zealand white rabbits were randomly assigned to one of two treatment groups. Group 1 subjects (n = 8) had N-O carboxymethylchitosan directly applied to the heart and retrosternal surfaces after sternotomy was performed, while subjects in group 2 (n = 8) had saline applied to these areas. After a period of 14 days the animals were sacrificed under anesthesia, and independent observers, blinded to treatment, graded the formation of pericardial adhesions. The severity of adhesion formation was significantly less in the group treated with N-O carboxymethylchitosan (p < .01). This study demonstrates that N-O carboxymethylchitosan markedly decreases the formation of poststernotomy adhesions in a large-animal model without untoward cardiac side effects. This hydrogel derivative may prove to be of great therapeutic value when used prophylactically in the setting of cardiac surgery.     

Prevention of Pericardial Adhesions with N-O Carboxymethylchitosan in the Rabbit Model

The presence of mediastinal adhesions significantly increases the morbidity and mortality of reoperative cardiac surgical procedures. Previous investigations have reported on the therapeutic utility of topical hydrogels in reducing the formation of postsurgical adhesions. The goal of the present study is to evaluate the ability of N-O carboxymethylchitosan (a glycosaminoglycan hydrogel derivative) to reduce the formation of postsurgical pericardial adhesions in a large-animal model. Sixteen adult New Zealand white rabbits were randomly assigned to one of two treatment groups. Group 1 subjects (n = 8) had N-O carboxymethylchitosan directly applied to the heart and retrosternal surfaces after sternotomy was performed, while subjects in group 2 (n = 8) had saline applied to these areas. After a period of 14 days the animals were sacrificed under anesthesia, and independent observers, blinded to treatment, graded the formation of pericardial adhesions. The severity of adhesion formation was significantly less in the group treated with N-O carboxymethylchitosan (p &lt; .01). This study demonstrates that N-O carboxymethylchitosan markedly decreases the formation of poststernotomy adhesions in a large-animal model without untoward cardiac side effects. This hydrogel derivative may prove to be of great therapeutic value when used prophylactically in the setting of cardiac surgery.