疏血通注射液对大鼠随意型皮瓣存活的影响

目的研究疏血通注射液对大鼠背部随意型皮瓣存活的影响。方法采用改良的大鼠McFarlane皮瓣制作方法,将Sprague Dawley大鼠随机分为疏血通实验组和生理盐水对照组,实验组每只每天腹腔注射疏血通注射液1．5mL／kg,对照组每只每天腹腔注射生理盐水1．5mL／kg。术后第7天处死大鼠分别进行皮瓣存活面积比的检测,并取皮瓣近、中、远区组织切片光镜下观察,免疫组化法检测血管内皮生长因子（VEGF）的表达。结果术后7d,实验组皮瓣的存活面积比为（72．52±2．23）％,对照组皮瓣的存活面积比为（50．36±2．37）％,实验组存活面积比显著高于对照组（P〈0．01）。实验组中区皮瓣的组织水肿、炎症细胞浸润情况明显比对照组减轻,并且出现大量的新生血管,中区新生血管密度（27．42±4．21）个／mm^2,与对照组（17．45±5．43）个／mm^2差异有统计学意义（P〈0．05）。实验组VEGF表达量为4731．24±448．99,对照组为2466．01±801．67,差异有统计学意义（P〈0．01）。结论疏血通注射液可能通过增加VEGF表达等途径,促进皮瓣新生血管增生,改善皮瓣血供,减轻炎症反应,从而改善大鼠随意型皮瓣的存活。     

腺病毒-VEGF基因重组体促进预构皮瓣成活的实验研究

目的：应用大鼠预构皮瓣模型,探讨基因治疗技术产生的血管内皮生长因子促进预构皮瓣血管新生和皮瓣存活的可能性,为临床上寻找加速预构皮瓣成熟的新方法提供实验依据。方法：20只SD大鼠每只腹部两侧各构建一个预构皮瓣,共构建40个皮瓣,每只大鼠两侧皮瓣按随机原则进行不同的处理,分别归于实验组或对照组,每组各20个皮瓣。于大鼠腹部两侧各标记3cm×2cm矩形预构区,短边平行于腹股沟韧带,自尾侧短边中点向后纵向切开后肢皮肤,剥离出长约2cm的股动静血管束,远端结扎切断。在两侧预构区域的中轴线上,于真皮与肉膜层间各制作一皮下隧道,实验组的隧道壁皮下组织内注射携带有VEGF基因的腺病毒,同法向所有对照组的隧道壁软组织内注射等量生理盐水。将已剥离好的血管束向颅侧翻转置入相应皮下隧道内。所有已植入股血管的预购区域2周后均被制成以植入血管束为蒂的岛状皮瓣,从两组中各取一个皮瓣进行免疫组化染色,观察有无VEGF生成,其余岛状皮瓣均缝回原处。形成岛状皮瓣后第七天观察皮瓣存活及血管新生情况。结果：实验组与对照组的皮瓣平均存活率分别为（90．48±1．89）％、（69．75±2．36）％,其差异有统计学意义（P〈0．01）;血管放射显影图上,实验组植入血管周围见广泛白色显影,尤以血管两端明显,而对照组新生血管显影仅局限于植入血管周围;组织学切片显示实验组植入血管周围新生血管丰富,以毛细血管为主,并见肉芽成份,对照组新生血管相对较少,两组间新生小血管管腔大小则无明显差异;免疫组化检测显示仅实验组皮瓣中有VEGF表达。结论：腺病毒-VEGF基因重组体能通过促进预构皮瓣的血管新生,增加预构皮瓣的存活率。     

VEGF促进预构皮瓣血管新生的实验研究

目的探讨VEGF重组蛋白促进大鼠预构皮瓣血管新生、提高皮瓣存活面积的可行性。方法建立大鼠腹部预构皮瓣模型;30只Wistar大鼠随机分为两组;局部应用VEGF165（组Ⅰ）、PBS（组Ⅱ）;4周后形成以植入血管为蒂的岛状皮瓣,原位缝合;术后7d对皮瓣存活、血管新生情况进行检测。结果组Ⅰ、组Ⅱ的皮瓣存活率分别为66．13％±9．9％,55．59％±13．06％（P〈0．05）;组Ⅰ与组Ⅱ比较,微血管显影血管网更丰富,范围更广,分支更粗,内含墨汁的血管在皮瓣的表皮真皮、皮下层均有分布;微血管计数组Ⅰ、组Ⅱ分别为25．83±6．33条／mm^2,26．5±5．61条／mm^2（p〉0．05）。结论VEGF可以促进预构皮瓣的血管新生,提高存活率。     

VEGF明胶缓释微球对大鼠背部随意皮瓣存活的影响

目的研究局部注射血管内皮生长因子(VEGF)复合明胶微球对SD大鼠背部随意皮瓣存活的影响.方法采用改良的乳化冷凝法交联制备复合VEGF的明胶缓释微球,将其注射于大鼠背部随意皮瓣,24只SD大鼠随机分为复合VEGF微球组(A组)、VEGF治疗组(B组)和对照组(C组),术后7天分别进行皮瓣存活率、新生血管计数的检测.结果术后7天皮瓣的存活率分别为(68.54±2.79)%,(58.65±3.26)%,(45.43±2.71)%,治疗组存活率显著高于对照组(P＜0.05),且存活质量A组最好;皮瓣内新生血管计数分别为(31.16±4.38),(25.41±4.06),(18.68±5.44)具有显著差异性.结论VEGF缓释微球可以促进缺血皮瓣的血管新生,提升皮瓣存活率.     

脂质体介导血管内皮生长因子对不同时间断蒂大鼠随意型皮瓣的影响

目的 通过血管内皮生长因子基因对大鼠随意型皮瓣的转染,探讨基因治疗对不同时间断蒂的大鼠随意型皮瓣成活的影响.方法 以SD大鼠为实验模型制作背部随意型皮瓣,实验组注入脂质体包裹的PcDNAVEGF165(目的 基因组),对照组分别注入PcDNA(空白质粒组)和生理盐水(生理盐水组),于用药后1、3、5、7 d,每组每时相点分别随机选取10只断蒂,断蒂后7 d处死大鼠,观察下述指标:①皮瓣成活率.②皮瓣组织标本行常规HE染色检测平均微血管数目及内径.③行VEGF免疫组织化学染色检测VEGF表达情况.④取皮瓣组织标本在电镜下观察超微结构.结果 ①皮瓣成活率:1、3、5、7 d断蒂实验组皮瓣成活率分别为(45.45±12.24)%、(82.95±3.81)%、(85.00±3.38)%、(85.96±3.25)%.1 d断蒂实验组与对照组比较差异无统计学意义(P>0.05),3、5、7 d断蒂各实验组明显高于相应对照组(P<0.05),3、5、7 d断蒂各实验组则随着断蒂时间的延迟差异无统计学意义(P>0.05).②平均微血管数目及内径:各实验组与相应对照组比较差异有统计学意义(P<0.05).③各实验组VEGF染色深度明显高于对照组(P<0.05).④超微结构:实验组内有新生血管形成,内皮细胞内可见较多粗面内质网,线粒体等结构,组织内成纤维细胞增多,细胞合成代谢旺盛.结论 皮下注射脂质体介导VEGF基因可提高皮瓣成活率,促进早期断蒂,是一种简单,高效,经济,相对安全的基因治疗方法.     

血管内皮生长因子促进跨区供血反流轴型皮瓣成活的实验研究

目的研究血管内皮生长因子（vascular endothelial growth factor，VEGF）的局部皮下注射对大鼠背部跨区供血反流轴型皮瓣成活的影响及效果。方法取20只SD大鼠，制备8cm×2cm大鼠背部跨区供血反流轴型皮瓣模型，随机分成两组，每组10只。实验组：于皮瓣远端7．5cm及6．5cm处共选择4个对称位点，分别予100ng／100μlVEGF溶液50μl；对照组：每一位点予生理盐水50μl。术后1～7d行皮瓣大体观察，并于7d处死大鼠，切取皮瓣，行皮瓣成活率测定、组织学观察及血管密度检测。结果大体观察，实验组皮瓣成活面积明显大于对照组，实验组皮瓣成活面积15．55±0．27cm^2，对照组13．42±0．57cm^2，差异有统计学意义（P〈0.01）。组织学观察，实验组皮瓣血管密度34．40±3．75个／10倍光镜下视野，对照组21．00±3．16个／10倍光镜下视野，差异有统计学意义（P〈0.01）。镜下见实验组有大量新生肉芽组织形成，胶原纤维排列规则，成纤维细胞较多，炎性细胞浸润程度轻；对照组新生肉芽组织少，胶原纤维凝集成块，成纤维细胞少，炎性细胞浸润程度重。结论VEGF在皮瓣成活早期，通过促进缺血皮瓣新生血管形成，增加血管数量，改善缺血组织的血液供应，促进皮瓣成活；在皮瓣形成时局部、单次、足量应用VEGF是促进跨区供血反流轴型皮瓣远端成活的有效方法。     

pcDNA3.1(+)载体携带血管内皮生长因子治疗大鼠缺血皮瓣

目的 观察注射真核表达载体pcDNA3.1(+)携带血管内皮生长因子(VEGF)基因后对大鼠缺血皮瓣存活的影响.方法 构建重组质粒pcDNA3.1(+)-VEGF,将SD大鼠随机分成3组,每组10只.pcDNA3.1(+)-VEGF组:于背部皮肤皮下多点注射pcDNA3.1(+)-VEGF 30 μg/100μl;VEGF组:多点注射VEGF蛋白100 ng/100μl;生理盐水(NS)组:注射生理盐水100μl,注射2d后在其背部形成7 cm×3 cm的全厚随意型皮瓣,48 h后按原设计掀起皮瓣并原位缝合.术后10 d测量皮瓣的成活面积,计算成活面积百分比,并行免疫组织化学检测.结果 皮瓣成活面积百分比:pcDNA3.1(+)-VEGF组为(79.1±3.5)％,VEGF组为(62.2±2.7)％,NS组为(59.9±3.1)％,pcDNA3.1(+)-VEGF组皮瓣成活面积明显高于其他两组(P＜0.05).结论 皮下注射pcDNA3.1(+ )-VEGF可促进新生血管的形成,比单纯注射VEGF蛋白更能提高皮瓣的成活率.     

血管生成素2与腹膜透析时腹膜血管新生的关系

目的 观察血管生成素2（Angpt-2）和腹膜透析（腹透）时腹膜血管新生的关系。 方法 5/6肾切除制作尿毒症大鼠模型,成模后在腹腔内植入腹透管,根据大鼠体质量每天经腹透管注入定量腹透液（4.25%,Dineal）。按腹透时间分为未腹透组、腹透10 d组、28 d组及56 d组。假手术非尿毒症非透析大鼠为对照组。大网膜抗CD31免疫组化染色后作血管计数,观察腹膜血管新生。用实时定量PCR和Western 印迹分别检测腹膜Angpt-2和血管内皮生长因子（VEGF）表达量变化,同时检测腹膜血管数和Angpt-2、VEGF表达量的关系。 结果 未腹透组、腹透10 d、28 d及56 d组腹膜血管数显著高于对照组[（5±3）、（10±5）、（17±5）及（19±4）比（1±1） 个/HP,均P < 0.05]。腹透28 d组腹膜血管数显著高于腹透10 d组（P < 0.05）,但与56 d组差异无统计学意义。未腹透组或腹透各组腹膜Angpt-2和VEGF表达显著高于对照组（均P < 0.01）,而Angpt-2和VEGF表达量并未随透析时间延长而增加。Angpt-2和VEGF表达量和腹膜血管数呈正相关（r = 0.7756,P < 0.01;r = 0.5223,P < 0.05）。 结论 尿毒症状态和腹透促进腹膜血管新生。腹膜Angpt-2表达增加和腹膜血管新生呈正相关。Angpt-2将可能成为治疗腹膜血管新生的另一靶点     

血管内皮生长因子和内抑素在STZ大鼠肾脏中的表达及意义

目的：研究血管内皮生长因子（VEGF）和内抑素（ENS）在2型糖尿病大鼠肾脏中的表达状况、比值变化及与肾脏微血管病变的关系。方法：将Wister大鼠设正常对照组和模型组，使用STZ诱导形成2型糖尿大鼠肾病模型，分别于2、4、8、12周，采用RT-PCR的方法观察大鼠肾脏VEGF和ENSmRNA的表达，并观察其比值变化，同时采用免疫组化观察VEGF蛋白的表达变化。结果：（1）糖尿病组2周时肾脏中VEGFmRNA开始上调（P〈0．05），4、8、12周时较正常对照组明显上调（P〈0．01）。（2）糖尿病组2周时肾脏中ENSmRNA的表达开始上调（P〈0，05），8、12周时表达明显上调（P〈0．01）。（3）糖尿病组2周时肾脏的VEGFmRNA／ENSmRNA值未见变化（P〉0．05），4周时升高（P〈0．05），12周时明显升高（P〈0．01）。（4）免疫组化显示糖尿病肾病组2周时VEGF升高，12周时升高更明显。结论：VEGF和ENS同时参与了糖尿病肾病的血管生成调控，两者表达水平的失衡是其新生血管形成的关键。     

水蛭素对大鼠随意型皮瓣存活的影响

目的 研究水蛭素对大鼠背部超长随意型皮瓣存活的影响.方法 采用改良大鼠"McFarlane flap"模型,将实验动物随机分为水蛭素实验组(水蛭素组)和生理盐水对照组(生理盐水组),水蛭素组局部注射3 ml(30 ATU)水蛭素,生理盐水组则注射3 ml生理盐水,连续注射7 d后分别检测两组皮瓣的存活面积百分比,并取皮瓣近、中、远段(即Ⅰ、Ⅱ、Ⅲ区)组织做光镜观察,免疫组化法检测血管内皮生长因子(VEGF)和碱性成纤维细胞因子(bFGF)的表达.结果 术后7 d,水蛭素组皮瓣的存活面积百分比为(69.52±3.23)%,生理盐水组为(50.36±2.37)%,水蛭素组显著高于生理盐水组,差异有统计学意义(P＜0.01);水蛭素组皮瓣坏死与存活并存的Ⅱ区,组织水肿、炎性细胞浸润情况明显比生理盐水组轻.水蛭素和生理盐水组皮瓣Ⅱ区的新生血管计数分别为(28.24±4.23)个/mm2和(17.45±5.43)个/mm2,两组比较差异有统计学意义(P＜0.05).通过计算累积吸光度A值(IA),得到水蛭素和生理盐水组VEGF阳性量分别为9262.23±896.99和4938.05±1623.67,bFGF阳性量分别为5122.83±1176.12和2779.45±472.00,水蛭组VEGF及bFGF的表达均高于生理盐水组,差异均有统计学意义(P＜0.01).结论 水蛭素可能通过体内一系列复杂的调控通路,最终增加VEGF、bFGF表达,促进皮瓣新生血管增生,改善皮瓣血供,减轻炎性反应,降低缺血皮瓣的坏死率,从而提高大鼠随意型皮瓣的存活.

Abstract：

Objective To investigate the effect of Hirudin on random skin flap survival in rats.Methods 24 SD rats were randomly divided into control group and experimental group. The "McFarlane flap(3 cm ×9 cm)" rat models were established on the rat dorsum. 3 ml Hirudin (30 ATU) was injected into the flap in the experimental group, while 3 ml saline in the control group. The injection was performed for 7 days. The flap survival area in the two groups was measured. The tissue samples were taken from proximal( Ⅰ ), middle( Ⅱ ) and distal( Ⅲ ) portions of flaps for histologic study. The VEGF and bFGF expression was also detected with immunohistochemistry method. Results 7 days after operation, the flap survival rate was ( 69.52 + 3.23 )% in the experimental group, while ( 50.36 ± 2.37 )% in control group,showing a significant difference between the two groups ( P ＜ 0.01 ). In the middle portion, tissue edema and infiltration of neutrophils in experimental group was markedly slighter than that in control group. The VEGF and bFGF expression and neovascularization was enhanced markedly in experimental group.Conclusions Hirudin can increase the survival of random pattern skin flaps. It may increase the VEGF,bFGF expression through a series of complex regulatory pathway. Then flap neovascularization is promoted and the flap blood supply is increased.     

rhBMP-2体外诱导骨质疏松大鼠BMSCs成骨及VEGF表达的研究

目的:观察骨形态发生蛋白-2对骨质疏松时骨髓基质干细胞(BMSCs)体外成骨及成骨因子VEGF表达的影响,为骨质疏松证的防治提供新的方法。方法:将20只6月龄,体重(300±20) g雌性SD大鼠双侧卵巢切除,术后3个月利用双能X线骨密度仪测量大鼠全身骨密度并与术前比较,确保造模成功,并运用全骨髓贴壁法培养骨质疏松大鼠BMSCs,倒置相差显微镜下观察BMSCs形态。随机把骨质疏松大鼠BMSCs 第2代(p2)细胞分成实验组和对照组,分别加入完全培养基(含rhBMP-2)、成骨诱导液进行成骨诱导。2周后茜素红染色法检测各组细胞钙结节的形成,酶标仪测定碱性磷酸酶活性及RT-PCR法检测VEGF的表达量。结果:(1)大鼠全身骨密度:手术前后大鼠全身骨密度分别为(0.179±0.007),(0.158±0.006) g/cm²,差异有统计学意义(t=4.180,P<0.05).(2)茜素红染色:BMSCs(P2)成骨诱导2周后实验组染色效果明显强与对照组。(3)碱性磷酸酶活性:BMSCs(P2)成骨诱导2周后碱性磷酸酶活性实验组明显高于对照组,分别为(15.62±1.27),(8.62±0.93) μg/prot,差异有统计学意义(t=7.709,P<0.01).(4)BMSCs(P2)成骨诱导2周后VEGF表达:实验组明显高于对照组,分别为3.723±0.143,0.950±0.072,差异有统计学意义(t=29.462,P<0.01).结论:rhBMP-2能提高去卵巢骨质疏松大鼠BMSCs的体外成骨能力,可促进成骨因子VEGF的表达,调控VEGF的表达可能是骨形态发生蛋白-2参与骨代谢的机制之一。     

The Effect of Mature Adipocyte-Derived Dedifferentiated Fat (DFAT) Cells on a Dorsal Skin Flap Model

Background: Dedifferentiated fat (DFAT) cells, isolated from mature adipose cell, have high proliferative potential and pluripotency. We report on the expansion of flap survival areas on the back of rats administrating DFAT cells. Materials and Methods: Intraperitoneal adipose tissue was collected from a male Sprague-Dawley (SD) rat. The mature fat cells were cultured on the ceiling surface of culture flask to isolate DFAT cells. On day 7 of the culture, the flask was inverted to allow normal adherent culture. A dorsal caudal-based random pattern flap measuring 2 × 9 cm was raised on each SD rat. We prepared a control group (n = 10) and a flap base injection group in which DFAT cells were injected 2 cm from the flap base (n = 10) and a flap center DFAT injection group (n = 10). In which DFAT cells at 1 × 106 cells/0.1 ml were injected beneath the skin muscle layers of the flap. The flap survival areas were assessed on day 14 after surgery. Results: The mean flap survival rates of the control group, flap center injection group and flap base injection group were 53.6 ± 6.1%, 50.6 ± 6.4% and 65.8 ± 2.4%, respectively. The flap survival areas significantly expanded in the flap base injection group (p < .05). In H-E staining beneath the skin muscle layer connective tissue thickened in the flap base injection group. In the India ink staining, abundant neovascularization was observed inside the thickened parts. Conclusion: The injection of DFAT cells into the flap base promoted the expansion of survival areas.     

Effects of Asiaticoside Treatment on the Survival of Random Skin Flaps in Rats

Abstract

Background: Asiaticoside (AS) is extracted from the traditional herbal medicine Centella asiatica, and has angiogenic, antioxidant, anti-inflammatory, and wound-healing effects. We investigated the effects of AS on skin flap survival. Methods: Dorsal McFarlane flaps were harvested from 36 rats and divided into two groups: an experimental group treated with 40?mg/kg AS administered orally once daily, and a control group administered normal saline in an identical manner. On day 2, superoxide dismutase (SOD) and malondialdehyde (MDA) levels, and production of the cytokines tumor necrosis factor-α and interleukin (IL)-6 were evaluated. On day 7, tissue slices were stained with hematoxylin and eosin. The expression of vascular endothelial growth factor (VEGF), IL-6, and IL-1β were immunohistochemically evaluated. Microcirculatory flow was measured using laser Doppler flowmetry. Flap angiography, using the lead oxide-gelatin injection technique, was performed with the aid of a soft X-ray machine. Results: The AS group exhibited greater mean flap survival area, improved microcirculatory flow, and higher expression levels of SOD and VEGF compared with the control group. However, MDA levels and the inflammatory response were significantly reduced. Conclusions: AS exhibits promise as a therapeutic option due to its effects on the viability and function of random skin flaps in rats.     

骶管注射对无坐骨神经痛性腰椎间盘突出症的疗效分析

目的：观察骶管注射疗法对无坐骨神经痛性腰椎间盘突出症患者的疗效。方法：2010年12月至2011年6月,对就诊的65例经CT或MRI检查证实为腰椎间盘突出或膨出所致的急性腰痛且无下肢放射痛的患者随机分为骶管注射组（试验组）和腰椎斜扳组（对照组）,试验组35例,男30例,女5例,年龄3356岁,平均（43．90±1．14）岁;对照组30例,男27例,女3例,年龄3457岁,平均（44．00±1．19）岁。两组的发病时间为1 h～3 d。分别行骶管注射或腰椎斜扳手法治疗。比较治疗前和治疗后30 min两组的VAS评分。结果：所有患者经治疗后急性腰痛症状明显缓解,骶管注射组和腰椎斜扳组的VAS评分分别从（6．63±0．97）和（6．67±0．96）分减至（3．06±1．51）和（3．93±1．20）分,两种治疗方法均能改善患者VAS评分,但骶管注射组治疗要优于腰椎斜板组（P 0．05）。结论：骶管注射和腰椎斜扳疗法对无坐骨神经痛性腰椎间盘突出症急性腰痛的患者具有快速缓解的作用,且前者的疗效更佳。     

Improvement of the skin flap survival with the bone marrow‐derived mononuclear cells transplantation in a rat model

Partial necrosis of skin flaps remains a significant problem in plastic and reconstructive surgery. In this study we attempted to evaluate the effect of bone marrow‐derived mononuclear cells (BM‐MNCs) transplantation on improvement of skin flap survival in a rat random pattern skin flap model. Thirty Wistar rats were divided into three groups with each consisting of 10 rats. BM‐MNCs and the adipose‐derived stem cells (ADSCs) were transplanted into the subcutaneous tissue in the area where the flap would be dissected. The flaps were then raised two days after cells transplantation. The animals receiving the preoperative Dulbecco's Modified Eagle Medium (DMEM) treatment were used as the controls. On the 7th postoperative day, the survival areas of flaps were measured and tissues were collected for examinations. The results showed that the mean survival areas were 46.33 ± 13.46% in the ADSCs group and 50.06 ± 13.82% in the BM‐MNCs group as the percentages of the total skin flaps, which were significantly higher than that in the control group (26.33 ± 7.14%) (P < 0.05). Histological analysis showed increased neovascularization in the flap treated with BM‐MNCs when compared with ADSCs transplantation. Survival BM‐MNCs and ADSCs were detected in the flap tissues. Higher levels of the basic fibroblast growth factor (bFGF) and vascular endothelium growth factor (VEGF) were found in the BM‐MNCs transplantation group (P < 0.05). The findings from this study demonstrated that preoperative treatment with BM‐MNCs transplantation could promote neovascularization and improve flap survival. These effects of BM‐MNCs on flap survival were comparable with ADSCs transplantation, but without necessity of in vitro cells expansion. © 2010 Wiley‐Liss, Inc. Microsurgery, 2010     

The effects of VEGF on survival of a random flap in the rat: examination of various routes of administration.

The purpose of the present study was to determine the effects of vascular endothelial growth factor (VEGF) on survival of a full thickness random pattern, McFarlane musculocutaneous flap in the rat. In addition, this study examined a number of different methods of VEGF delivery in an attempt to determine the most effective route of administration. A 2 x 8 cm full thickness dorsal flap with the pedicle remaining attached at the anterior end was elevated in 72 male Sprague-Dawley rats. The rats were randomised into six groups and immediately received the following treatment: Group I (n = 12): systemic VEGF injection into the femoral vein (50 microg/ml); Group II (n = 10): multiple systemic VEGF injections at 0, 24 and 48 h post flap elevation (50 microg/ml); Group III (n = 12): subdermal VEGF injection into the flap (1 microg/ml); Group IV (n = 12): subfascial VEGF injections into the recipient bed (1 microg/ml); Group V (n = 10): topical VEGF onto the recipient bed (1 microg/ml); Group VI (n = 16): control group with no treatment. Following 5 days recovery, the area of flap survival was measured. Mean flap survival ranged from 91% in Group II to 78% in Group V, and was significantly greater in all experimental groups (P< 0.001 for Groups I-IV and P< 0.05 for Group V) as compared to the control group (mean survival of 66%). The only significant difference between the experimental groups was between the mean survival in Group II and Group V (P< 0. 05). Histological analysis demonstrated a qualitatively greater amount of granulation tissue and neovascularisation in the experimental groups. These results support the notion that VEGF rescues tissue at risk of hypoxic damage by inducing angiogenesis, and the use of growth factors such as VEGF holds promise as a method of increasing skin viability.     

Vascular endothelial growth factor gene therapy in improvement of skin paddle survival in a rat TRAM flap model

The use of growth factors in inducing angiogenesis and enhancing flap viability has provided promising results. Targeted gene therapy has evolved in hopes of increasing the longevity and effectiveness of these growth factor treatments. The purpose of this study was to examine the effect of preoperative treatment by vascular endothelial growth factor (VEGF) plasmid DNA on the survival of the skin paddle in a rat pedicled TRAM flap model. In part one of the study, VEGF plasmid DNA incorporated with lipofectamine was injected into the subcutaneous fascial layer of the upper abdominal walls of the rats. At 4 days postoperatively, biopsies were taken from the injected area for histology and VEGF protein quantification. In part two of the study, the rats were divided into three groups. In one experimental group, the VEGF plasmid DNA was injected into the subcutaneous fascial layer in the area where the TRAM flap would be elevated. In two control groups, the plasmid without VEGF DNA and saline were injected. The flaps were raised and replaced 4 days after injection. Flap survival was examined. Results showed that tissue receiving VEGF plasmid DNA injection revealed new vessel sprouting. The VEGF levels in these tissues were significantly higher than in the tissue not receiving VEGF plasmid DNA. In flap survival, the mean viable area of the skin paddles receiving preoperative VEGF plasmid DNA injection was significantly larger than that of flaps receiving no VEGF plasmid DNA and saline injection. This study demonstrated that preoperative subcutaneous injection of VEGF plasmid DNA could induce angiogenesis and improve TRAM skin paddle survival.     

Kidney transplantation decreases the tissue level of advanced glycosylation end-products

We have studied the effect of chronic renal failure (CRF) andkidney transplantation on advanced glycosylation end-products(AGE) measured as collagen-linked fluorescence (CLF) in theskin and peritoneum of non-diabetic patients. Of 34 patientswith CRF, 18 were studied before the commencement of peritonealdialysis (CRF group), and 16 were studied 5–31 weeks afterkidney transplantation (transplant group). The control groupconsisted of 24 patients with normal renal function. Skin CLFin the CRF group (20.9 ± 2.02 U/mg) was higher than inthe control (8.52±1.08 U/mg, P = 0.0001) and transplantgroups (10.7 ± 2.43 U/mg, P=0.003). Peritoneal CLF inthe CRF group (30.5 ± 5.64 U/mg) was higher than in thecontrol group (16.1 ±2.25 U/mg, P=0.031) but was notdifferent from the transplant group (19.4 ± 3.66 U/mg,P=0.11). Peritoneal CLF of control and transplant groups werenot different (P= 0.45). The results of this study suggest thatrestoration of renal function affects tissue AGE levels.