屏障材料预防肌腱粘连的研究进展

肌腱与腱周组织粘连是肌腱损伤修复术后最主要的并发症,使用屏障材料预防肌腱粘连是一种最直接有效的方法。传统使用的不可吸收材料常常会导致严重免疫反应或阻隔肌腱营养而导致肌腱愈合不良,且常需二次手术取出,已基本淘汰。可吸收膜和水凝胶等具有良好通透性及组织相容性的可吸收大分子材料是目前研究的重点。使用自体或异体组织材料重建腱鞘也可预防肌腱粘连,但自体组织重建腱鞘损伤较大且手术复杂,异体组织常常受到安全性、伦理学等诸多限制,而组织工程化腱鞘可能是未来预防肌腱粘连的一个重要研究方向。     

屏障材料预防肌腱粘连的研究进展

肌腱与腱周组织粘连是肌腱损伤修复术后最主要的并发症,使用屏障材料预防肌腱粘连是一种最直接有效的方法。传统使用的不可吸收材料常常会导致严重免疫反应或阻隔肌腱营养而导致肌腱愈合不良,且常需二次手术取出,已基本淘汰。可吸收膜和水凝胶等具有良好通透性及组织相容性的可吸收大分子材料是目前研究的重点。使用自体或异体组织材料重建腱鞘也可预防肌腱粘连,但自体组织重建腱鞘损伤较大且手术复杂,异体组织常常受到安全性、伦理学等诸多限制,而组织工程化腱鞘可能是未来预防肌腱粘连的一个重要研究方向。     

丹参注射液对同种异体肌腱移植后粘连防治的实验研究

目的:探讨局部应用丹参注射液(Salvia Miltiorrhiza,SM)对异体肌腱移植后粘连的影响.方法:使用深低温冷冻处理的同种异体肌腱修复缺损的大鼠屈趾肌腱,72只大鼠随机分为2组,A组为试验组,腱周局部注射丹参注射液,B组为对照组,注射生理盐水(Saline).术后2、4、8周处死动物,标本进行大体观察、组织学观察及生物力学测定.结果:A组粘连范围小,粘连等级评分与B组相比有统计学意义,力学测定结果显示A组与B组无统计学意义.结论:丹参注射液能有效减轻肌腱移植后粘连.     

防止肌腱粘连及促进其愈合的研究进展

随着对肌腱愈合研究的不断深入和发展,预防肌腱粘连以及促进其愈合的方法越来越多。通过改进缝合方法、修复腱鞘或采用替代品、置入药物或药物薄膜及早期康复等治疗来有效预防肌腱粘连;通过重建腱鞘、药物、生长因子、基因干预等促进肌腱愈合。本文就近年来防止肌腱粘连及促进其愈合方面的研究予以综述。     

丝裂霉素C诱发大鼠外周血G0期淋巴细胞核损伤指标的比较观察

本文用不同剂量的MMC处理大鼠外周血,放置18小时后直接制备淋巴细胞血涂片,进行观察。实验结果表明,MMC可诱发G_(?)期淋巴细胞的核损伤。本实验对各种核损伤指标进行了比较研究,发现微核、核变形和核碎裂等指标与MMC剂量间有很好的相关性。作者认为,大鼠外周血G_(?)期淋巴细胞核异常测试法比传统的微核测试法更敏感、合理,在致突变试验中可作为初筛的体外短期测试法,值得进一步研究。     

丝裂霉素C诱发人精子染色体畸变的研究

人精子经最终浓度分别为７．５,１５．３０μｇ／ｍｌ丝裂霉素Ｃ（ＭＭＣ）处理１ｈ后与去透明带地鼠卵受精,制备第１次卵裂中期相进行核型分析,以探讨ＭＭＣ对人精子的诱变效应。结果显示明显的量效关系。染色单体型畸变是诱发畸变的主要类型,但仍观察到一定数量染色体型畸变,表明ＭＭＣ作用于人精子与通常拟紫外线致断剂作用于体细胞诱变的结果并不完全一样。３６．８９％的诱发畸变为重接型,表明金黄地鼠卵母细胞内的修复系统能够修复ＭＭＣ所引起的人精子ＤＮＡ损伤     

头状轮生链霉菌中丝裂霉素C抗性基因的克隆及功能研究

头状轮生链霉菌(\%Streptoverticillium caespitosus\%)ATCC27422是抗肿瘤药物丝裂霉素的主要产生菌,实验通过诱变筛选获得不产生丝裂霉素同时对丝裂霉素C敏感的阻断变种S6,并以它为受体宿主,以质粒pIJ699为载体,建立野生型头状轮生链霉菌菌株ATCC27422的基因库。采用鸟枪法克隆技术,从库中筛选获得含有丝裂霉素C抗性基因的62kb外源片段的克隆子。将含此外源片段的质粒pLX5导入变铅青链霉菌(\%Streptomyces lividans\%)获得表达。并且首次成功地运用电穿孔法将pLX5导入野生型菌株中,使其对丝裂霉素C的抗性大幅度提高：最低抑制浓度(MIC)由原来的200μg/mL上升至1000μg/mL以上。摇瓶发酵实验表明：单位菌量的ATCC27422(pLX5)的丝裂霉素产量高于野生菌株ATCC27422,因此丝裂霉素C抗性与产量之间存在一定的相关性。     

小梁切除术中应用丝裂霉素C 对角膜内皮细胞的影响

目的:观察小梁切除术中应用丝裂霉素C(MMC)对角膜内皮细胞的影响。方法:收集2010年9月2011年5月在我院行小梁切除术的青光眼患者60例(78眼),随机分为术中应用丝裂霉素C的36例(46眼)患者为A组,术中不用丝裂霉素C的24例(32眼)为B组,分别观察术前、术后1个月和术后3个月两组眼压(IOP)、角膜内皮细胞的密度(CD)、平均细胞面积(AVG)及细胞面积变异系数(CV),分析其数量的改变及两组间的差异。结果:A组术前眼压为(35.4±13.7)mmHg,B组术前眼压为(32.5±13.5)mmHg差异无统计学意义(P>0.05),A组术后1个月及术后3个月眼压分别为(15.7±3.7)mmHg、(17.0±3.2)mmHg,均低于B组的(19.4±3.7)mmHg、(20.2±2.1)mmHg,差异有统计学意义(P<0.05)。A组术前、术后1个月及术后3个月角膜内皮细胞密度分别为(2475±484)个/mm2、(2199±373)个/mm2、(2164±332)个/mm2;平均细胞面积分别为(431.4±67.6)μm2、(480.6±66.8)μm2、(463.8±46.2)μm2;细胞面积变异系数分别为(31.1±7.4)%、(34.4±6.3)%、(31.2±7.5)%;术后1个月及术后3个月各参数与术前比较,差异均有统计学意义(P<0.05)。B组术前、术后1个月及术后3个月角膜内皮细胞密度分别为(2342±94)个/mm2、(2185±215)个/mm2、(2074±218)个/mm2;平均细胞面积分别为(453.9±94.8)μm2、(516.3±100.8)μm2、(499.81±106.4)μm2;细胞面积变异系数分别为(30.2±3.0)%、(32.7±2.9)%、(31.4±4.3)%;除术后3个月角膜内皮细胞与术前比较有意义(P<0.05)外,余参数术后1个月及术后3个月与术前比较差异均无统计学意义(P>0.05)。术后1个月A组的角膜内皮细胞丢失率为10.4%高于B组的6.1%,差异有统计学意义(P<0.05);术后3个月A组的角膜内皮细胞丢失率为11.1%高于B组的10.0%,差异无统计学意义(P>0.05)。结论:小梁切除术中用丝裂霉素C的降压效果比不用丝裂霉素C的效果好,但短期内前者角膜内皮细胞的丢失率高于后者。     

小梁切除术中应用丝裂霉素C对角膜内皮细胞的影响

目的：观察小梁切除术中应用丝裂霉素C（MMC）对角膜内皮细胞的影响。方法：收集2010年9月2011年5月在我院行小梁切除术的青光眼患者60例（78眼）,随机分为术中应用丝裂霉素c的36例（46眼）患者为A组,术中不用丝裂霉素c的24例（32眼）为B组。分别观察术前、术后1个月和术后3个月两组眼压（10P）、角膜内皮细胞的密度（co）、平均细胞面积（AVG）及细胞面积变异系数（cv）,分析其数量的改变及两组间的差异。结果：A组术前眼压为（35．4±13．7）mmHg,B组术前眼压为（32．5±13．5）mmHg差异无统计学意义（P〉0．05）,A组术后1个月及术后3个月眼压分别为（15．7±3．7）mmHg、（17．0±3．2）mmHg,均低于B组的（19．4±3．7）mmHg、（20．2±2．1）mmHg,差异有统计学意义（P〈0．05）。A组术前、术后1个月及术后3个月角膜内皮细胞密度分别为（2475±484）个／mm2、（2199±373）个／mm2、（2164±332）个／mm2;平均细胞面积分别为（431．4±67．6）μm2、（480．6±66．8）μm2、（463．8±46．2）μm2;细胞面积变异系数分别为（31．1±7．4）％、（34．4±6．3）％、（31．2±7．5）％;术后1个月及术后3个月各参数与术前比较,差异均有统计学意义（P〈0．05）。B组术前、术后1个月及术后3个月角膜内皮细胞密度分别为（2342±94）个／mm2、（2185＋215）个／mm2、（2074218）个／mm2;平均细胞面积分别为（453．9土94．8）μm2、（516.3±100．8）μm2、（499．81＋106．4）μm2;细胞面积变异系数分别为（30．2土3．0）％、（32．7±2．9）％、（31．4±4．3）％;除术后3个月角膜内皮细胞与术前比较有意义（P〈0．05）外,余参数术后1个月及术后3个月与术前比较差异均无统计学意义（P〉0．05）。术后1个月A组的角膜内皮细胞丢失率为10．4％高于B组的6．1％,差异有统计学意义（P〈0．05）;术后3个月A组的角膜内皮细胞丢失率为11．1％高于B组的10．0％,差异无统计学意义（P〉0．05）。结论：小梁切除术中用丝裂霉素C的降压效果比不用丝裂霉素C的效果好,但短期内前者角膜内皮细胞的丢失率高于后者。     

Determination of biomechanical characteristics of restrictive adhesions and of functional impairment after flexor tendon surgery: a methodological study of rabbits.

Formation of restrictive adhesions is one of the main obstacles in rehabilitation following hand surgery. Most experimental work, however, involves only a macroscopic and/or histologic evaluation of the amount of adhesions, and their functional characteristics are poorly described. The aim of this study was to develop an experimental technique for characterization of the biomechanical properties of the finger-tendon unit. An instrument was developed for continuous and simultaneous recording of tensile load, tendon excursion and angular rotation in the distal interphalangeal joint of rabbit digits. Utilizing this instrument, it was revealed that the first 50 degrees of flexion required virtually no tensile load either in unoperated digits or immediately after tenorrhaphy. Thereafter, the load required to obtain further flexion was progressively increased. The strength of adhesions, determined 2 weeks after tenorrhaphy, was best expressed as the maximum tensile load recorded before 50 degrees of flexion was reached. This measurement could also be used to register the strength of the tendon repair and to detect partial tendon rupture during the measurement. The technique allows both adequate measurements of the strength of the adhesions and of the tendon gliding ability after flexor tendon surgery.     

A new friction tester of the flexor tendon.

We have developed a new device to measure the friction force and calculate the friction coefficient between a rabbit flexor tendon, a pulley and a proximal phalanx. The flexor digitorum fibularis tendon of a rabbit was taken intact with the proximal phalanx, and tendon pulleys were attached to both ends of the bone. Both ends of the tendon were clamped to acrylic plates and connected to stainless-steel plates equipped with strain gauges. A pretension of 1.96 N was applied so as not to loosen the tendon. The proximal phalanx was fixed to an acrylic plate on the actuator, which gave 8 mm of transfer to the acrylic plate at a speed of 2 mm/s. The interface between the tendon and the surrounded tissue created the friction force, when the load was applied on the distal pulley. The friction force could be obtained from the difference between the tension of both ends of the tendon, which was measured with strain gauges and sampled with a personal computer. The friction force and the friction coefficient were calculated from the measured force and the applied load. The load and the pre-loading time, which was defined as loading duration before gliding, were varied in order to observe the change of the friction coefficient. The friction coefficient was not affected by the load and increased with the pre-loading time. The value of mu(s) ranged from 0.027 to 0.111 (0.072 +/- 0.023), and that of (mu)d ranged from 0.010 to 0.069 (0.039 +/- 0.014) (pre-loading time was 5 s). Our method will allow for the examination of various surgical treatments and lubricants. Moreover, it can be applied to other tissues of any animals with similar structures to the rabbit's digitorum.     

Temporal response of canine flexor tendon to limb suspension

Tendon disuse, or stress deprivation, frequently accompanies clinical disorders and treatments, yet the metabolism of tendons subject to stress deprivation has rarely been investigated systematically. The effects of stress deprivation on canine flexor tendon were investigated in this study. One adult canine forepaw was suspended for 21 or 42 days. Control forepaws were collected from dogs that had no intervention on their limbs and paws. The expression of collagen I and III was not significantly altered in the tendons disused for 21 days but was significantly decreased at 42 days (P < 0.03). The expression of collagen II, aggrecan, decorin, and fibronectin was significantly decreased in the tendons in the suspended limbs at 21 days (P < 0.002) and further reduced at 42 days. With stress deprivation, the expression of matrix metalloproteinase 2 (MMP2) was significantly increased (P < 0.004) at 21 and 42 days. The expression of MMP3 was significantly decreased at 21 and 42 days (P < 0.03). The expression of MMP13 was not altered with stress deprivation at 21 and 42 days. The expression of MMP14 was significantly increased at 21 days (P = 0.0015) and returned to the control level at 42 days. Tissue inhibitor of metalloproteinase 1 (TIMP1) expression was decreased after the limbs were suspended for 42 days (P = 0.0043), but not 21 days. However, TIMP2 expression was not significantly different from control at 21 or 42 days. Furthermore, the cross-sectional area of the stress-deprived tendons at 42 days was decreased compared with the control group (P < 0.01). The intervention method in this study did not result in any alteration of stiffness of the tendon. Our study demonstrated that stress deprivation decreases the anabolic process and increases the catabolic process of extracellular matrix in flexor tendon.     

Action of mitomycin C on mouse spermatogonia

The induction of chromosome aberrations in mouse spermatogonia and bone marrow cells by treatment with Mitomycin (MC) was tested. The following dosages were used: 3.5; 1.75; 0.35; and 0.035 mg/kg body weight. Chromatid interchanges and terminal deletions were induced in both tissues. Regarding the chromosome damage, spermatogonia seemed to be more sensitive to the test substance than bone marrow cells.The aberrations observed were considered to represent the cause of dominant lethals induced in spermatocytes after treatment with MC by others. The squash technique adapted for examination of mitoses of mouse spermatogonia proved to be a useful tool in testing potential chemical mutagens.