任常,趙大春,朱蘭
中國醫(yī)學科學院 北京協(xié)和醫(yī)學院 北京協(xié)和醫(yī)院1婦產科2病理科,北京100730
羧甲基殼聚糖預防兔手術后粘連的效果:大體和病理學大樣本觀察
任常1,趙大春2,朱蘭1
中國醫(yī)學科學院 北京協(xié)和醫(yī)學院 北京協(xié)和醫(yī)院1婦產科2病理科,北京100730
目的評價羧甲基殼聚糖(N,O-carboxymethyl chitosan,NOCC)預防兔手術后粘連的效果。方法220只雌性大耳白兔采用雙子宮模型造成手術粘連,隨機分組后接受單純造模手術(對照組)或造模手術+關腹前腹腔內注射NOCC(NOCC組)。所有手術均由同一位術者完成。每組各22只大耳白兔在實驗設計的5個觀察時間點(術后3、7、14、28和42 d)分別被處死并評估其粘連情況,包括范圍、類型和強度等大體情況和炎癥、纖維化以及新生血管等鏡下情況。結果NOCC組在術后3 d時其粘連的范圍(P=0.0337)和強度(P=0.0271)以及炎癥反應情況(P<0.0001)均顯著輕于對照組。在術后14 d內,NOCC組的纖維化情況均明顯輕于對照組(P均<0.0005)。與對照組相比,NOCC組的粘連強度在術后14、28、42 d均明顯減輕(P均<0.05),而其粘連類型評分在術后28和42 d也明顯降低(P均<0.05)。結論經NOCC處理后,兔盆腹腔術后粘連大體和病理學評分均不同程度降低。應用NOCC可有效預防盆腹腔術后粘連。
羧甲基殼聚糖;術后粘連;兔雙子宮模型;隨機對照研究
Med J PUMCH,2016,7(5):347-352
盆腹腔粘連常繼發(fā)于各種手術操作,其發(fā)生率高達94%[1-2]。粘連是術后腸梗阻、腹痛、不孕等的主要原因,不但給患者帶來痛苦,也增加了家庭和社會的經濟負擔[3]。提高手術技巧并不一定能減少術后粘連及相關并發(fā)癥的發(fā)生。Ten Broek等[4]分析了27項關于改善手術操作和粘連相關預后的研究,發(fā)現沒有任何一種操作能顯著降低術后小腸梗阻的發(fā)生率。因此需要借助其他防粘連措施來減少術后粘連形成,如抗氧化劑、抗炎藥物、促纖溶藥物,以及局部應用液態(tài)或者隔膜類材料[5-8]。殼聚糖因具有止血、抗病原微生物和抑制腫瘤生長因子-β的特性而被用于預防術后粘連[9-11]。羧甲基殼聚糖(N,O-carboxymethyl chitosan,NOCC)通過在殼聚糖內核上添加羧甲基,形成一種水溶性、帶負電荷、生物相容的聚合物。NOCC已被證實具有降低術后粘連形成的作用,其作用可能通過阻斷炎癥細胞粘附以及物理屏障實現[12]。但現有研究多從大體角度研究其防粘連效果,且樣本量有限。本研究旨在通過大樣本隨機對照實驗探討應用NOCC對于兔雙子宮模型術后粘連的大體和鏡下評分的影響。
研究動物和材料
健康性成熟非孕雌性日本大耳白兔220只,體重2.16~2.80 kg,由中國醫(yī)學科學院北京協(xié)和醫(yī)學院實驗動物研究所提供,符合國家醫(yī)用實驗動物標準。本實驗通過北京協(xié)和醫(yī)院實驗動物倫理委員會批準。
3-0薇喬可吸收縫線(強生公司,美國)、1-0慕斯絲線(強生公司,美國)、2%羧甲基殼聚糖(醫(yī)用幾丁糖,1 ml規(guī)格,上海其勝生物制劑有限公司,中國)。
實驗設計
220只大耳白兔首先按照電腦隨機數字法被隨機分配接受單純造模手術(對照組,n=110)或者造模手術+關腹前腹腔內注射NOCC(NOCC組,n= 110),每組再進一步通過電腦隨機數字法隨機分配入5個觀察時間點(術后3、7、14、28、42 d)亞組(n=22)。所有實驗動物均按照雙子宮手術模型由同一位術者進行手術操作,并根據分組于預定日期處死進行大體和鏡下觀察[13-14]。
粘連評價
由同一位檢查者結合婦科手術系統(tǒng)和美國生育學會(American Fertility Society,AFS)的粘連評分標準采用盲法對所有實驗動物粘連的范圍、類型和強度進行大體評分,取粘連最重部位的評分進行計算[14-15]。由兩位病理醫(yī)生采用盲法同時對鏡下所見粘連的急慢性炎癥、纖維化以及新生血管形成情況進行評分后取平均值[16-17]。
統(tǒng)計學處理
采用SAS 9.1進行數據錄入和分析。符合正態(tài)分布的數據采用均數±標準差進行描述,應用t檢驗進行統(tǒng)計分析。不符合正態(tài)分布的數據采用中位數和四分位數進行描述,應用非參數方法比較兩組間差異。雙側檢驗P<0.05認為差異有統(tǒng)計學意義。
一般情況
NOCC組和對照組大耳白兔的平均月齡分別為(5.30±0.23)個月和(5.43±0.31)個月,體重分別為(2.43±0.31)kg和(2.53±0.33)kg,兩組間具有可比性(P>0.05)。
粘連評價
大體觀察:術后3 d時,粘連多局限在子宮和膀胱之間,粘連疏松、呈膜狀,沒有血管形成(圖1A)。NOCC組創(chuàng)面沒有明顯NOCC殘留,粘連較對照組更疏松,其粘連的范圍和強度評分顯著低于對照組(P=0.0337,P=0.0271)。術后7 d時,粘連范圍和強度均增加,但仍然易于分離(圖1B)。NOCC組的粘連較對照組更疏松。術后14 d時,粘連的范圍和強度與術后7 d相似,新生血管不明顯。NOCC組粘連仍較對照組疏松,其粘連強度評分明顯低于對照組(P=0.0410)。術后28 d時,粘連范圍增加,新生血管網開始形成(圖1C)。NOCC組的粘連范圍與對照組相比較局限,新生血管不明顯,其粘連的類型和強度評分均顯著低于對照組(P=0.0210,P<0.0001)。術后42 d,與術后28 d相比,粘連的范圍和強度均減輕(圖1D)。在NOCC組,粘連的范圍、強度和類型評分均較術后28 d時降低;同時,NOCC組的粘連比對照組更疏松、新生血管更細更少(圖1E),其粘連的類型和強度評分均顯著低于對照組(P=0.0027,P=0.0002)(表1)。
表1 NOCC組和對照組在術后5個時間點的大體粘連評價情況
圖1 大耳白兔雙子宮造模手術后盆腹腔粘連的大體觀察因兩組變化趨勢相似,故A~D均展示對照組大體所見;A.術后3 d對照組:子宮和膀胱間的疏松、膜狀粘連;B.術后7 d對照組:可見1例新生血管(箭頭);C.術后28 d對照組:新生血管網形成(箭頭);D.術后42 d對照組:粘連范圍較28 d降低;E.術后42 d NOCC組:粘連更疏松,新生血管更細NOCC:羧甲基殼聚糖
鏡下觀察:術后3 d時,炎癥細胞浸潤很明顯,組織水腫,有成纖維細胞或肌纖維母細胞漂浮(圖2A)。NOCC組的微膿腫更少,其炎癥反應和纖維化程度均顯著輕于對照組(P<0.0001,P=0.0004)。術后7 d時,急性炎癥滲出逐漸為慢性炎癥所取代。在部分標本中,肉芽組織周圍可見由幾個或甚至單個內皮細胞構成的新生微毛細管(圖2B)。NOCC組的類蛋白滲出較常見,而纖維化不明顯,其評分與對照組的差異有統(tǒng)計學意義(P<0.0001)。術后14 d時,急性炎癥細胞變得稀疏,炎癥逐漸消退,而纖維增生增加;漿膜表面的纖維化主要由膠原和一些平滑肌樣細胞組成。NOCC組的膠原相對疏松,其粘連的纖維化程度明顯輕于對照組(P=0.0002)。術后28 d時,纖維化逐漸變得致密,新生血管開始形成血管網。很多小血管已具有小動脈的完整結構,部分直徑已超過100 μm(圖2C)。NOCC組的新生血管直徑與對照組相似。術后42 d時,漿膜表面的纖維組織范圍和纖維增生的厚度降低,但密度增加(圖2D)。新生血管的數量和形態(tài)與術后28 d相似(圖2E)(表2)。
圖2 大耳白兔雙子宮造模手術后盆腹腔粘連的病理表現(HE染色,×150)A.術后3 d對照組:可見微膿腫(箭頭);B.術后7 d對照組:可見新生微毛細管(箭頭);C.術后28 d對照組:可見一條有完整結構的大毛細血管,在其下方可見慢性炎癥細胞浸潤(箭頭);D.術后42 d對照組:纖維密度增加;E.術后42 d NOCC組:新生血管與術后28 d相似NOCC:同圖1
表2 NOCC組和對照組在術后5個時間點的鏡下粘連評價情況
很多研究已探討NOCC預防粘連的效果和機制,但很少有研究結合大體和鏡下所見[18]。為更好地了解其防粘連的作用,筆者研究了兩種條件下觀察到的粘連變化情況。
之前有大鼠實驗發(fā)現NOCC能顯著降低術后腹腔粘連的發(fā)生率和粘連強度[19-20]。在本實驗中,術后3 d NOCC組的炎癥評分顯著低于對照組。證據顯示炎癥反應,包括成纖維細胞的激活及其在組織損傷部位的聚集,對于粘連形成過程的啟動至關重要[21]。術后16~36 h是創(chuàng)面粘連形成最敏感的時期[22-23]。在這個關鍵階段,NOCC可以起到物理隔膜的作用,將受損的漿膜分離開,使炎癥反應局限的同時也能稀釋炎性滲出物,從而減少局部炎癥細胞和細胞因子,進而緩解炎癥反應[24],因此減輕了大體觀察所見粘連的范圍和強度。
術后1周粘連的范圍和強度均增加,這與Li等[25]的實驗結果相似,其原因可能與此階段基質金屬蛋白酶-9表達最強有關。而筆者同時觀察到此時NOCC組的炎癥反應更重,但與對照組相比差異無統(tǒng)計學意義。此發(fā)現提示盡管NOCC具有生物相容性,它對于機體畢竟還是一種異物。膠原化是腹膜損傷所引起的生理反應中永久性纖維化形成的指標。本實驗發(fā)現膠原化在術后7 d最明顯。其他研究也證實膠原合成在術后5~7 d達峰值[26-27],從而有助于粘連的成熟[28-29]。
術后1周后是對于粘連形成很關鍵的纖維化發(fā)生的重要階段,而在NOCC組此時纖維化并不明顯。Costain等[19]的體內動物實驗也提示NOCC不刺激纖維化。這可以解釋NOCC組粘連強度顯著降低的原因。還有研究發(fā)現術后14 d NOCC組粘連的范圍和程度較對照組和生理鹽水組均顯著降低[30-31]。術后14 d,即使在腹腔內有血液存在的情況下,NOCC仍能減少粘連的形成和再形成[20]。
本實驗發(fā)現與對照組相比,NOCC組術后4周后粘連的強度和類型均顯著減輕,Diamond等[32]的臨床研究也曾證實這一點。提示在NOCC完全吸收以后,其防粘連的作用還持續(xù)存在,而兩組間組織的修復沒有差異。Costain等[19]采用了三種不同的模型:腹主動脈吻合、大腸吻合、腹部皮膚切開來進一步評估NOCC對于手術切口愈合的作用,結果發(fā)現在所有模型中應用NOCC都沒有影響切口愈合的強度。
綜上,NOCC使用方便,可以迅速涂布在創(chuàng)面上全面覆蓋創(chuàng)面,并且在有血液或體液存在的情況下也能發(fā)揮預防術后粘連的作用。NOCC在粘連形成的初始階段能保持穩(wěn)定,隨后逐漸降解,可以顯著減少粘連而不影響創(chuàng)面的愈合,因此是預防盆腹腔粘連的一種有效的措施。本研究將進一步通過特殊染色繼續(xù)觀察鏡下膠原的變化,以更全面地評估NOCC對于鏡下粘連情況的影響。
致謝:感謝中國醫(yī)學科學院北京協(xié)和醫(yī)學院實驗動物研究所及曾海佩、孫繼超在動物實驗中給予的幫助;感謝北京協(xié)和醫(yī)學院統(tǒng)計和流行病學教研室的韓偉助理研究員在實驗設計和統(tǒng)計分析方面給予的幫助。
[1]Stanciu D,Menzies D.The magnitude of adhesion-related problems[J].Colorectal Dis,2007,9:35-38.
[2]Liakakos T,Thomakos N,Fine PM,et al.Peritoneal adhesions:etiology,pathophysiology,and clinical significance.Recent advances in prevention and management[J].Dig Surg,2001,18:260-273.
[3]Wiseman DM.Disorders of adhesions or adhesion-related disorder:monolithic entities or part of something bigger-CAPPS?[J].Semin Reprod Med,2008,26:356-368.
[4]Ten Broek RP,Kok-Krant N,Bakkum EA,et al.Different surgical techniques to reduce post-operative adhesion formation:a systematic review and meta-analysis[J].Hum Reprod Update,2013,19:12-25.
[5]Sahbaz A,Aynioglu O,Isik H,et al.Bromelain:a natural proteolytic for intra-abdominal adhesion prevention[J].Int J Surg,2015,14:7-11.
[6]Moraloglu O,I?ik H,Kilic S,et al.Effect of bevacizumab on postoperative adhesion formation in a rat uterine horn adhesion model and the correlation with vascular endothelial growth factor and Ki-67 immunopositivity[J].Fertil Steril,2011,95:2638-2641.
[7]Sakai S,Ueda K,Taya M.Peritoneal adhesion prevention by a biodegradable hyaluronic acid-based hydrogel formed in situ through a cascade enzyme reaction initiated by contact with body fluid on tissue surfaces[J].Acta Biomater,2015,24: 152-158.
[8]Hellebrekers BW,Trimbos-Kemper GC,van Blitterswijk CA,et al.Effects of five different barrier materials on postsurgical adhesion formation in the rat[J].Hum Reprod,2000,15:1358-1363.
[9]Ong SY,Wu J,Moochhala SM,et al.Development of a chitosan based wound dressing with improved hemostatic and antimicrobial properties[J].Biomaterials,2008,29:4323-4332.
[10]Rabea EI,Badawy ME,Stevens CV,et al.Chitosan as antimicrobial agent:Applications and mode of action[J].Biomacromolecules,2003,4:1457-1465.
[11]Krause TJ,Goldsmith NK,Ebner S,et al.An inhibitor of cell proliferation associated with adhesion formation is suppressed by N,O-carboxymethyl chitosan[J].J Invest Surg,1998,11:105-113.
[12]Zhou J,Liwski RS,Elson C,et al.Reduction in postsurgical adhesion formation after cardiac surgery in a rabbit model using N,O-carboxymethyl chitosan to block cell adherence[J].J Thorac Cardiovasc Surg,2008,135:777-783.
[13]Ren C,Zhu L,Sun JC.Creation of an animal model for postoperative adhesion prevention[J].Zhongguo Yi Xue Ke Xue Yuan Xue Bao,2012,34:109-115.
[14]Adhesion Scoring Group.Improvement of interobserver reproducibility of adhesion scoring systems[J].Fertil Steril,1994,62:984-988.
[15]American Fertility Society.The American Fertility Society classification of adnexal adhesions,distal tubal occlusion,tubal occlusion secondary to tubal ligation,tubal pregnancies,Mullerian anomalies and intrauterine adhesions[J].Fertil Steril,1988,49:944-955.
[16]Ersoy E,Ozturk V,Yazgan A,et al.Comparison of the two types of bioresorbable barriers to prevent intra-abdominal adhesions in rats[J].J Gastrointest Surg,2009,13: 282-286.
[17]Hooker GD,Taylor BM,Driman DK.Prevention of adhesion formation with use of sodium hyaluronate-based bioresorbable membrane in a rat model of ventral hernia repair with polypropylene mesh-A randomised,controlled study[J].Surgery,1999,125:211-216.
[18]Ahmad G,Mackie FL,Iles DA,et al.Fluid and pharmacological agents for adhesion prevention after gynaecological surgery[J].Cochrane Database Syst Rev,2014,7:CD001298.
[19]Costain DJ,Kennedy R,Ciona C,et al.Prevention of postsurgical adhesions with N,O-carboxymethyl chitosan:examination of the most efficacious preparation and the effect of N,O-carboxymethyl chitosan on postsurgical healing[J].Surgery,1997,121:314-319.
[20]Zhou J,Elson C,Lee TDG.Reduction in postoperative adhesion formation and re-formation after an abdominal operation with the use of N,O-carboxymethyl chitosan[J].Surgery,2004,135:307-312.
[21]Wang D,Mo J,Pan S,et al.Prevention of postoperative peritoneal adhesions by O-carboxymethyl chitosan in a rat cecal abrasion mode[J].Clin Invest Med,2010,33:E254-E260.
[22]Ricketts SA,Sibbons PD,Green CJ.Quantitative analysis of the development of experimentally induced post surgical adhesions:a microstereological study[J].Int J Exp Pathol,1999,80:325-334.
[23]Harris ES,Morgan RF,Rodeheaver GT.Analysis of the kinetics of peritoneal adhesion formation in the rat and evaluation of potential antiadhesive agents[J].Surgery,1995,117:663-669.
[24]Yeo Y,Highley CB,Bellas E,et al.In situ cross-linkable hyaluronic acid hydrogels prevent post-operative abdominal adhesions in a rabbit model[J].Biomaterials,2006,27: 4698-4705.
[25]Li XD,Xia DL,Shen LL,et al.Effect of“phase change”complex on postoperative adhesion prevention[J].J Surg Res,2016,202:216-224.
[26]Haney AF,Doty E.The formation of coalescing peritoneal adhesions requires injury to both contacting peritoneal surfaces[J].Fertil Steril,1994,61:767-775.
[27]van Hinsbergh VW,Kooistra T,Scheffer MA,et al.Characterization and fibrinolytic properties of human omental tissue mesothelial cells.Comparison with endothelial cells[J].Blood,1990,75:1490-1497.
[28]Hickey MJ.Role of inducible nitric oxide synthase in the regulation of leukocyte recruitment[J].Clin Sci,2001,100: 1-12.
[29]Milligan DW,Raftery AT.Observations on the pathogenesis of peritoneal adhesions:a light and electron microscopical study[J].Br J Surg,1974,61:274-280.
[30]Duran B,Ak D,Cetin A,et al.Reduction of postoperative adhesions byN,O-carboxymethylchitosanandspermine NONOate in rats[J].Exp Anim,2003,52:267-272.
[31]Cetin M,Ak D,Duran B,et al.Use of methylene blue and N,O-carboxymethyl chitosan to prevent postoperative adhesions in a rat uterine horn model[J].Fertil Steril,2003,80 Suppl 2:698-701.
[32]Diamond MP,Luciano A,Johns DA,et al.Reduction of postoperative adhesions by N,O-carboxymethyl chitosan:a pilot study[J].Fertil Steril,2003,80:631-636.
Prevention of Postoperative Adhesions with N,O-carboxymethyl Chitosan in Rabbit: A Large-sample Gross and Histopathological Observation
REN Chang1,ZHAO Da-chun2,ZHU Lan1
1Department of Obstetrics&Gynecology,2Department of Pathology,Peking Union Medical College Hospital,Chinese Academy of Medical Sciences&Peking Union Medical College,Beijing 100730,China
ZHU LanTel:010-69155649,E-mail:zhu_julie@vip.sina.com
ObjectiveTo assess the effect of N,O-carboxymethyl chitosan(NOCC)in preventing postoperative adhesion in a rabbit model.MethodsDouble uterine horn model was established in 220 female rabbits to induce postoperative adhesion.The rabbits were randomized to receive either adhesion-inducing operation only(control group)or adhesion-inducing operation+intraperitoneal injection of NOCC before closure(NOCC group).All the operations were performed by one operator.Twenty-two rabbits from each group were euthanized at one of the five different time points(postoperative day 3,7,14,28,and 42),and adhesion formation was scored both grossly(extent,type,and tenacity)and histopathologically(inflammation,fibrosis,and vascularization).ResultsThe extent(P=0.0337)and tenacity of adhesion (P=0.0271)as well as inflammation(P<0.0001)were lower in the NOCC group than in the control group on day 3.Fibrosis was less obvious in the NOCC group compared to the control group(P<0.0005) before day 14.The tenacity scores of adhesion on day 14,28,and 42 were significantly lower in the NOCC group than in the control group(all P<0.05),while the type scores were obviously lower in the NOCCgroup on day 28 and 42(all P<0.05).ConclusionsTreatment with NOCC could reduce both gross and histopathological scores of surgery-induced abdominopelvic adhesions in rabbits.NOCC could be an effective therapy for preventing postoperative abdominopelvic adhesion.
N,O-carboxymethyl chitosan;postoperative adhesion;rabbit double uterine horn model;randomized controlled study
朱蘭電話:010-69155649,E-mail:zhu_julie@vip.sina.com
R713
A
1674-9081(2016)05-0347-06
10.3969/j.issn.1674-9081.2016.05.005
2016-07-05)