深Ⅱ度烫伤大鼠创面血管内皮细胞增殖与凋亡变化的初步研究

目的观察大鼠深Ⅱ度烫伤创面愈合过程中创基微小血管内皮细胞增殖与凋亡的变化特征,探讨血管的形成与退缩在创伤修复中的作用.方法利用大鼠5%深Ⅱ度烫伤模型,将72只Wistar大鼠随机分为正常对照和单纯烫伤两组.于伤后0.5d、1d、3d、7d、14d和21d采取创面皮肤标本,HE病理学染色和免疫组织化学技术检测创面组织真皮内血管内皮细胞PCNA和TUNEL的表达变化规律.结果深Ⅱ度烫伤的大鼠伤后3d,创面出现少量的肉芽组织,7d时肉芽组织已充满创面,再上皮化速率为30%,14d的再上皮化率达70%,至21d,创面完全闭合,真皮内小血管的数量减少.大鼠烫伤后3d,创面基底的真皮组织内出现PCNA阳性的血管内皮细胞,随后阳性表达逐渐增多,14d时达到高峰.至伤后21d,PCNA的阳性表达略有下降.而创伤愈合初期罕见TUNEL阳性的细胞,21d时,TUNEL标记阳性的细胞显著增多.结论烫伤大鼠创面中血管内皮细胞的增殖与凋亡活动与创面的愈合进程有密切的关系.血管形成与退缩在时程上协调变化是组织正常修复的重要步骤.     

大鼠深Ⅱ度烫伤创面愈合中血管形成与血流变化特点

目的：观察大鼠深Ⅱ度烫伤模型创面愈合中血管形成与血流改变的特点。方法：Wistar大鼠48只,随机分为A、B两组,A组（n=42）：为组织病理观察组,根据实验设计又分伤后即刻、1天、3天、7天、14天及21天及正常对照组,每组6只;B组（n=6）：为血流量检测组。在实验大鼠背部制作深Ⅱ度烫伤模型,A组大鼠在各时间点活杀取材,进行病理和免疫组化检测;B组大鼠连续检测背部同一部位正常皮肤及伤后各时间点的创面血流量。结果：烫伤大鼠伤后3～7天,肉芽组织内出现单个的不成腔的血管内皮细胞,数目随肉芽组织的增多而逐渐增加,后逐渐形成管腔;伤后14天,肉芽组织内有腔毛细血管进一步增多,已出现结构较完整的成熟小血管;伤后21天血管形态和数量已接近正常皮肤。深Ⅱ度烫伤大鼠伤后即刻,皮肤血流量锐减为正常皮肤血流量的51％;伤后3天时,创面血流量仅迭正常血流量的68％;至伤后14天,创面血流量升到正常值的88％;14天后逐渐正常。结论：在皮肤深Ⅱ度烫伤创面愈合过程中,随着肉芽组织内内皮细胞数量和结构的变化,创面的血流量不断增加,前者的变化是后者变化的基础。     

左旋精氨酸对糖尿病大鼠烧伤创面血管形成的影响

目的　观察左旋 (L)精氨酸对糖尿病大鼠烧伤创面修复过程中血管形成的影响。 方法雄性SD大鼠 ,设烫伤对照 (A)组、糖尿病烫伤 (B)组、甘氨酸对照 (C)组和L 精氨酸干预 (D)组 ,每组各 2 5只。B、C、D组大鼠通过腹腔注射链脲佐菌素 (STZ)建立糖尿病模型 ,C、D组分别管饲甘氨酸和L 精氨酸 2 0 0mg·kg-1·d-1。8周后取各组大鼠 (每组 5只 )背部皮肤组织测定糖含量。之后各组大鼠给予 2 0 %TBSA深Ⅱ度烫伤 ,于伤后 3、7、14、2 1d测量创面面积 ,计算创面愈合率 ;采用CD34免疫组织化学染色计算微血管密度 (MVD);检测创面组织释放一氧化氮 (NO)、血管内皮生长因子(VEGF)和转化生长因子 (TGF)β1含量。　结果　与B组相比 ,D组大鼠创面愈合率从伤后第 7天起显著增加为 [( 4 4.10± 3.5 0 ) % ,P <0 0 5 ],创面MVD值在伤后各时相点均显著增加 ( P <0 0 5 ),创面组织中释放NO、VEGF和TGF β1量增加 ,皮肤组织糖含量降低为 ( 1.380± 0 .12 0 )mg/g。　 结论L 精氨酸可通过增加NO、VEGF和TGF β1的合成与释放 ,降低皮肤组织糖含量 ,增加糖尿病大鼠烧伤创面的血管形成 ,并促进创面愈合     

rhGM-CSF与胰岛素联合应用对糖尿病大鼠烫伤创面TGF-β_1和FGF-2表达的影响

目的:拟通过检测分析局部联合应用重组人粒细胞巨噬细胞集落刺激因子(Recombinant human granulocytemacrophage colony-stimulating factor,rh GM-CSF)和胰岛素对糖尿病大鼠深Ⅱ度烫伤创面中转化生长因子β_1(Transforming growth factor-β_1,TGF-β_1)、碱性成纤维细胞生长因子(Basic fibroblast growth factor-2,FGF-2)以及CD34表达的影响,初步探讨局部联合应用rh GM-CSF和胰岛素促进糖尿病难愈性创面愈合的可能作用机制。方法:雄性SD大鼠制备糖尿病深Ⅱ度烫伤模型,随机分为糖尿病对照组、胰岛素用药组、rhGM-CSF用药组以及联合用药组,同时建立正常对照组。分别于伤后1、3、7、11、15、21d计算创面愈合率,观察创面组织形态学情况,并检测创面中TGF-β_1、FGF-2以及CD34的表达情况。结果:伤后7、11、15、21d,正常对照组、联合用药组创面愈合率均高于其余各组,糖尿病对照组创面愈合率均低于其余各组,差异有统计学意义(P0.05)。伤后3~21d,正常对照组、联合用药组TGF-β_1、FGF-2表达均显著高于其余各组,糖尿病对照组最低,差异有统计学意义(P0.05)。伤后7~21d,正常对照组、联合用药组CD34表达均高于其余各组,各时间点糖尿病对照组最低,差异有统计学意义(P0.05)。结论:局部联合应用rh GM-CSF和胰岛素可通过促进糖尿病大鼠深Ⅱ度烫伤创面血管化、纤维化和上皮化,明显促进创面愈合,提高创面愈合质量,其机制可能与二者联合上调创面中TGF-β_1、FGF-2以及CD34的表达有关。     

局部联合应用NGF及胰岛素对糖尿病大鼠烫伤创面血管形成及Bcl-2、Bax表达的影响

目的探讨局部应用NGF联合胰岛素对糖尿病大鼠烫伤创面血管中凋亡相关因子Bcl-2、Bax表达的影响及创面愈合的机制。方法取75只清洁级雄性Wistar大鼠,体重200～220 g,随机分为正常对照组(A组)、糖尿病对照组(B组)、胰岛素治疗组(C组)、NGF治疗组(D组)、NGF联合胰岛素治疗组(E组),每组15只。B、C、D、E组大鼠采用两步给药法腹腔注射链脲佐菌素(streptozotocin,STZ)建立糖尿病模型,STZ剂量分别为第1天10 mg/kg,第3天50 mg/kg;A组给予相同剂量柠檬酸缓冲液。模型制备后1个月,采用水蒸气烫伤法于各组大鼠背部制备2个深Ⅱ度烫伤创面。烫伤模型制备后,A、B组创面外敷3层生理盐水纱布;C组创面外敷3层浸润5 U胰岛素诺和灵30R的纱布,并每日腹部皮下注射诺和灵30R 4～6 U/kg;D组创面外敷3层浸润5 mL NGF溶液(25 U/mL)的纱布;E组联合C、D组方法处理。观察大鼠一般情况,伤后7、11、15、21 d大体观察各组创面愈合情况并计算创面愈合率,伤后3、7、11、15、21 d取创面组织行组织学及免疫组织化学染色观察,检测创面Bcl-2、Bax、CD34的表达并计算微血管密度。结果各组大鼠均存活至实验完成。随时间延长,各组创面逐渐缩小,其中E组创面愈合速度、皮肤角化、毛发生长及肉芽组织和胶原纤维生长均优于其余各组。伤后各时间点E组创面愈合率均高于其余各组,差异有统计学意义(P<0.05)。伤后随时间延长,各组CD34、Bcl-2表达逐渐增强,至15 d达高峰,21 d表达减弱;E组各时间点表达均强于其他各组(P<0.05)。伤后3 d各组均未见Bax表达,7 d后开始见新生血管内皮细胞Bax表达,且随时间延长表达逐渐增强,其中E组表达强度均低于其余各组(P<0.05)。结论局部联合应用NGF和胰岛素可通过抑制创面血管内皮细胞凋亡、增加创面血管生成,促进糖尿病大鼠创面愈合。     

纳米银抗菌凝胶对大鼠深Ⅱ度烫伤创面愈合及巨噬细胞数量和微血管密度的影响

目的:观察纳米银抗菌凝胶联合重组人粒细胞巨噬细胞集落刺激因子(rhGM-CSF)对大鼠深Ⅱ度烫伤创面愈合、巨噬细胞数量以及微血管再生的影响。方法:选取健康SD大鼠114只(6只作为非烫伤正常对照组,不作任何处理),剩余SD大鼠按照随机数字法分为3组,rhGM-CSF组、联合组和模型组,每组36只。制作深Ⅱ度烫伤创面模型,rhGM-CSF组大鼠创面涂抹rhGM-CSF,联合组应用纳米银抗菌凝胶和rhGM-CSF涂抹,模型组不作任何处理。比较各组创面愈合率,创面巨噬细胞数量以及微血管密度数量。结果:同一时间点,rhGM-CSF组和联合组愈合率均高于模型组,且联合组愈合率显著大于rhGM-CSF组,差异有统计学意义(P0.05);联合组第3、11、14天创面浸润巨噬细胞数量均少于模型组和rhGM-CSF组(P0.05);第3、7、11天,联合组微血管数量显著高于模型组和rhGM-CSF组,差异有统计学意义(P0.05)。结论:纳米银抗菌凝胶联合rhGM-CSF治疗深Ⅱ度烫伤效果确切,可以通过影响烫伤创面巨噬细胞数量和微血管生成促进烫伤创面愈合。     

rhPDGF对糖尿病鼠全层皮肤缺损创面微血管形成的影响和意义

目的:观察外源性重组人血小板源性生长因子(rhPDGF)对全层皮肤缺损的糖尿病鼠创面愈合过程中微血管形成的影响及促创面愈合的作用。方法:利用大鼠全层皮肤缺损创面愈合模型,将26只非糖尿病鼠52个创面分为3组:①A组为糖尿病大鼠创伤自然愈合组;②B组为接受rhPDGF治疗的糖尿病大鼠创伤愈合组;③C组为赋性剂组。于伤后3 d、7 d和14 d采取创面皮肤标本,用组织病理HE和血管Ⅷ因子抗体免疫组织化学染色技术检测创面肉芽再生与再血管化情况进行观察,同时观察创面的愈合情况。结果:全层皮肤缺损糖尿病鼠创面肉芽组织中微血管的形成数量少,采用赋性剂对照组与糖尿病鼠自然愈合组无显著差别。但外源性使用rhPDGF后,肉芽组织的形成量明显增多,内含的微小血管数量显著增加,愈合能力明显增强。结论:糖尿病大鼠微血管形成障碍可能是其创面愈合延迟的重要因素。而应用外源性的PDGF有助于微血管的形成,可以改善糖尿病鼠的创面愈合能力。     

荷负电气溶胶治疗Ⅱ度烧伤创面的临床效果及病理学观察

目的观察荷负电气溶胶(下称气溶胶)治疗Ⅱ度烧伤创面的效果。方法选择单纯浅Ⅱ、深Ⅱ度烧伤患者,随机分为:(1)气溶胶组:浅Ⅱ度180例、深Ⅱ度100例,伤后6h~2d开始用气溶胶治疗创面,l~2次/d,1.5h/次。(2)对照组:浅Ⅱ、深Ⅱ度患者各30例,常规治疗。(3)自身对照组:浅Ⅱ、深Ⅱ度患者各10例,同上用气溶胶治疗,但同一患者部分创面覆盖无菌金属片屏蔽气溶胶(屏蔽组),部分创面不屏蔽(非屏蔽组)。观察气溶胶治疗过程中患者创面的大体变化,治疗前后进行创面细菌培养,并监测其肝、肾功能及血生化指标有无改变。记录各组患者创面愈合时间。另制作深Ⅱ度烫伤大鼠模型,同前分为气溶胶组和对照组并治疗。取两组大鼠治疗前及治疗后1、2、3周的创面组织标本,作病理学观察。结果气溶胶治疗后患者创面渗出少,治疗前后均无细菌生长。总体来讲,气溶胶治疗前后患者肝、肾功能及血生化指标无明显改变。气溶胶组患者浅Ⅱ度创面伤后(6.3±1.6)d愈合,深Ⅱ度创面(15.1±3.1)d愈合,明显短于对照组相同深度创面[(11.3±1.4)、(21.2±1.4)d,P<0.01]。自身对照组中,相同烧伤深度的非屏蔽组与屏蔽组比较,创面愈合时间也明显缩短(P<0.01)。病理学检查显示,气溶胶组大鼠治疗后第3周皮肤结构已基本恢复正常,而对照组此时恢复较差。结论气溶胶能有效促进Ⅱ度烧伤创面的愈合且使用安全。     

VEGF165-胰岛素复合凝胶对糖尿病大鼠局部深Ⅱ度烫伤创面MVD及Ⅰ型胶原蛋白表达的影响

目的:制备外用VEGF165-胰岛素复合凝胶并观察其对糖尿病大鼠深Ⅱ度烫伤创面愈合的作用。方法:以新型凝胶卡波姆980为基质,分别加入VEGF165、胰岛素,分别配制成胰岛素凝胶、VEGF165凝胶、VEGF165-胰岛素复合凝胶和空白对照凝胶。观察各组凝胶性状,检测其p H值。75只SPF级雄性Wistar大鼠,体重190~290g,随机分为正常对照组、糖尿病对照组、胰岛素凝胶组、VEGF165凝胶组、VEGF165-胰岛素复合凝胶组,每组15只。各组大鼠禁食12h后,除正常对照组外,其余各组一次性腹腔注射链脲佐菌素(55 mg/kg)制备1型糖尿病模型,正常对照组大鼠注射相同剂量柠檬酸钠缓冲液。1型糖尿病大鼠造模成功后,采用恒温水浴箱80℃,制备深Ⅱ度烫伤模型。正常对照组、糖尿病对照组创面外敷空白凝胶基质,其余各组外敷对应凝胶制剂,每天换药1次。深Ⅱ度烫伤造模成功后观察各组大鼠存活情况,于3、7、11、15、21天时点观察糖尿病大鼠创面愈合情况并计算创面愈合率,在各时点随机处死每组3只大鼠取烫伤皮肤全层留取标本,行组织学切片及免疫组化染色观察各时点炎性细胞,微血管形成及胶原蛋白。结果:制备的各组凝胶透明,保湿性极佳,黏附性良好,便于涂抹及清洗,无组织毒性。各组大鼠无感染及死亡发生。3天后烫伤各组创面无明显缩小,7、11、15、21天时,VEGF165-胰岛素复合凝胶组创面愈合率最高,糖尿病组最低。VEGF165-胰岛素复合凝胶组愈合率与其余各组比较,差异均有统计学意义(P0.05)。病理切片观察示各时点VEGF165-胰岛素复合凝胶组肉芽组织形成及上皮化均优于其余各组。免疫组化染色示各组微血管数量、Ⅰ型胶原蛋白阳性率均于3天开始表达,且随时间阳性细胞增多明显;各时间点VEGF165-胰岛素复合凝胶组微血管密度及Ⅰ型胶原蛋白最高,糖尿病组最低,与其余各组比较以及VEGF165-胰岛素复合凝胶组、糖尿病组间比较差异均有统计学意义(P0.05)。结论:糖尿病大鼠皮肤深Ⅱ度烫伤外用VEGF165-胰岛素复合凝胶对创面愈合有明显的促进作用     

神经肽P物质与烫伤创面愈合关系的实验研究

目的　探讨神经肽P物质(SP)与烫伤创面愈合之间的关系。　方法　(1)制作大鼠不同深度烫伤模型,分别于伤后1、3、7、14d致死,用放射免疫法测定创面SP含量。(2)将大鼠肉芽组织成纤维细胞(GTF)用不同培养液培养,分为空白对照组、SP组及SP SP受体拮抗剂(Spantide)组。体外检测SP及Spantide对GTF增殖活性[以吸光度(A)值表示]及凋亡率的影响。　结果　(1)伤后1d,浅Ⅱ、深Ⅱ、Ⅲ度烫伤创面SP含量分别为(145±78)、(94±48)、(53±27)ng/g,深Ⅱ度创面与其余两者比较,差异有统计学意义(P<0 01).浅Ⅱ度创面伤后3、7dSP含量显著增高;深Ⅱ度创面伤后7、14dSP含量显著增高;Ⅲ度创面伤后SP含量无显著变化。(2)SP增强GTF增殖活性(空白对照组A为0. 21±0. 05,SP组A为0. 36±0 07,P<0. 01)并抑制其凋亡,Spantide可抑制SP对GTF的作用。　结论　SP可促进GTF增殖,创面SP含量与创面损伤程度及愈合能力关系密切。     

Effects of plasma fibronectin on the healing of full-thickness skin wounds in streptozotocin-induced diabetic rats

BACKGROUND: Fibronectin has been shown to assist in wound healing. Impaired wound healing in diabetes mellitus is characterized by a reduction in plasma fibronectin (pFn) at the wound site. This study investigated whether topical application of pFn could improve the impaired wound healing in diabetic rats. MATERIALS AND METHODS: Full-thickness skin wounds were created on the backs of streptozotocin (STZ)-induced diabetic rats. Immediately, human pFn was introduced into the wound bed, while wounds receiving human serum albumin or normal saline were used as controls. Wound closure was monitored using well-recognized wound-healing parameters: epithelialization, vascularization, collagen deposition, and migration of fibroblasts were examined histologically. Transforming growth factor (TGF)-beta1 was measured by immunochemistry. Hydroxyproline levels also were assessed in the wound skin. RESULTS: Wound closure was significantly accelerated by local application of pFn. Furthermore, pFn-treated wounds showed increased fibroblast vascularization, collagen regeneration, and epithelialization. The numbers of infiltrating fibroblasts expressing TGF-beta1 and hydroxyproline levels in pFn-treated wounds were significantly higher than those in the controls. CONCLUSIONS: pFn can improve the impaired healing of diabetic wounds and this effect might involve an increase in the activity of fibroblasts and increased release of TGF-beta1.     

Abnormal regulation of neo-vascularisation in deep partial thickness scalds in rats with diabetes mellitus

Objective

This study observed the degree of neo-vascularisation and differential expression of angiogenesis growth factors and their receptor in deep partial-thickness scald wound with diabetes mellitus.

Methods

Sixty Sprague-Dawley rats were randomised into a control group and an STZ-induced diabetic group, inflicted with partial-thickness scalding of 20% total body surface area (20% TBSA) on the back. Wound specimens were harvested immediately after scald and on 1, 3, 7, 10, 14 and 21 post-scald days (PSDs) to observe histological changes, and wound healing rates were calculated. The degree of neo-vascularisation in wound (labelled with blue microsphere) and the quantity of vascular endothelial cells (labelled with red CD31) were also measured by double-labelling immunofluorescence. Angiopoietin-1 (Ang-1), Angiopoietin-2 (Ang-2), Tie-2, vascular endothelial growth factor (VEGF) and Flt-1 messenger RNA (mRNA) were analysed by real-time RT-PCR. Ang-1, Ang-2 and VEGF protein expressions were measured by Western blotting.

Results

Wound healing was markedly impaired in diabetic rats. The diabetic rats show inhibited vascularity in the wound edge at every time point (the quantitation of vascularity was 60.0 ± 3.0 in the control group and 12.0 ± 1.4 in the diabetic group, p < 0.01 on day 7). Although neo-vascularisation in the number of endothelial cells was not significantly different compared with the normal group, part of new vascular endothelial cells did not form the vascular function. After injury, expression of Ang-2 mRNA and protein were increased in both groups, and the normal group showed decreases on day 7, 14 and 21, whereas the diabetic group showed significant increases. Although the expression VEGF and its receptors before injury was higher than the normal group, the level at 1, 3 and 7 days after injury was significantly lower than that 14 days, and that at 21 days after injury was significantly higher than the normal group.

Conclusion

Vascular endothelial cells can proliferate actively in the diabetic wound with deep partial-thickness burns, but it is still poor in blood supply due to lack of functional capillaries. The mechanism may be related to sustained abnormal high expression of Ang-2 and down-regulated VEGF.     

Diabetic wound healing in a MMP9‐/‐ mouse model

Reduced mobilization of endothelial progenitor cells (EPCs) from the bone marrow (BM) and impaired EPC recruitment into the wound represent a fundamental deficiency in the chronic ulcers. However, mechanistic understanding of the role of BM‐derived EPCs in cutaneous wound neovascularization and healing remains incomplete, which impedes development of EPC‐based wound healing therapies. The objective of this study was to determine the role of EPCs in wound neovascularization and healing both under normal conditions and using single deficiency (EPC) or double‐deficiency (EPC + diabetes) models of wound healing. MMP9 knockout (MMP9 KO) mouse model was utilized, where impaired EPC mobilization can be rescued by stem cell factor (SCF). The hypotheses were: (1) MMP9 KO mice exhibit impaired wound neovascularization and healing, which are further exacerbated with diabetes; (2) these impairments can be rescued by SCF administration. Full‐thickness excisional wounds with silicone splints to minimize contraction were created on MMP9 KO mice with/without streptozotocin‐induced diabetes in the presence or absence of tail‐vein injected SCF. Wound morphology, vascularization, inflammation, and EPC mobilization and recruitment were quantified at day 7 postwounding. Results demonstrate no difference in wound closure and granulation tissue area between any groups. MMP9 deficiency significantly impairs wound neovascularization, increases inflammation, decreases collagen deposition, and decreases peripheral blood EPC (pb‐EPC) counts when compared with wild‐type (WT). Diabetes further increases inflammation, but does not cause further impairment in vascularization, as compared with MMP9 KO group. SCF improves neovascularization and increases EPCs to WT levels (both nondiabetic and diabetic MMP9 KO groups), while exacerbating inflammation in all groups. SCF rescues EPC‐deficiency and impaired wound neovascularization in both diabetic and nondiabetic MMP9 KO mice. Overall, the results demonstrate that BM‐derived EPCs play a significant role during wound neovascularization and that the SCF‐based therapy with controlled inflammation could be a viable approach to enhance healing in chronic diabetic wounds.     

糖尿病大鼠深Ⅱ度烫伤后真皮成纤维细胞的生物学特征

目的观察糖尿病（DM）大鼠深Ⅱ度烫伤肝创面皮肤组织及真皮成纤维细胞（Fb）生物学特征，探讨其与DM创面愈合延迟的病理关系。方法将90只SD火鼠分为DM组（50只）和NM组（NM，40只），DM纽大鼠制成链脲菌索绣导的DM模型，之后将两纰大鼠造成10％TBSA深Ⅱ度烫伤。各组大鼠均于伤前及伤后3、7、14、21d（每组每时相点6只）留收创面皮肤组织标本，对其各项生物学特征进行检测。结果与NM组大鼠比较，DM组伤前真皮厚度明显变薄（P〈0．01）、胶原排列紊乱、真皮内出现大量的慢性炎性细胞浸润，皮肤糖含量升高（DM组2．77mg／g，NM组0．85mg／g，P〈0．01）和高级糖基化终产物（AGEs）蓄积。深Ⅱ度埂伤后，DM组大鼠Fb的S期细胞百分比和羟脯氨酸合成量明显低于NM组，而Fb的凋亡率却明显高于NM组（P〈0．05或0．01）。结论DM大鼠合并深Ⅱ度烫伤后真皮中Fb的乍物学特征异常，可能与局部皮肤组织糖含量升高和AGEs的蓄积有关，推测是DM患者容易并发慢性溃疡的病理基础之一。     

β内啡肽与μ型-阿片受体在深Ⅱ度烫伤大鼠创面愈合过程中的表达

目的观察β内啡肽和μ型-阿片受体（MOR）在深Ⅱ度烫伤大鼠创面愈合过程中的表达。方法将36只Wistar大鼠随机分为对照组（6只）、烫伤组（30只）。烫伤组大鼠被造成5％TBSA深Ⅱ度烫伤，对照组仅模拟烫伤。于伤后即刻及伤后3、7、14、21d取创面组织，采用免疫荧光标记法检测B内啡肽和MOR的表达情况。结果对照组大鼠皮肤组织内β内啡肽和MOR主要分布于表皮、真皮交界的周围神经纤维、表皮的角质形成细胞、真皮的成纤维细胞中，强度较弱。伤后3d，烫伤组B内啡肽表达达峰值（196±16，P＜0．01），在皮肤全层均有表达；MOR集中表达在基底层和基底上的角质形成细胞。伤后7、14d烫伤组B内啡肽仍大量表达。伤后7d，烫伤组MOR的表达进一步增强，胶原排列紊乱；14d时部分创面再上皮化，MOR表达达高峰（306±23，P＜0．01）。伤后21d，烫伤组创面完全再上皮化，周围神经末梢接近并抵达表皮、真皮交界，胶原排列较整齐，β内啡肽的表达（31±24）与对照组（30±18）接近；但MOR的表达（56±16）仍然高于对照组（28±15）。结论烫伤后β内啡肽和MOR的表达具有一定的时效性，这种变化可能影响了创面愈合。     

蜕皮甾酮和骨髓间充质干细胞对早期创面抗炎作用的初步研究

目的:研究蜕皮甾酮(EDS)及骨髓间充质干细胞(BMSC)对烫伤创面的早期抗炎作用.方法:新西兰大耳白兔18只,每只兔用烫伤仪制备4个创面并经病理证实为深Ⅱ度,随机标记为空白对照组(A组)、EDS组(B组)、BMSC(C组)、EDS+BMSC(D组).烫伤后5、10、15 d各处死6只家兔,观察炎性细胞浸润度、创面愈合...     

Tissue-engineered provisional matrix as a novel approach to enhance diabetic wound healing

Inherent pathologies associated with diabetic wound microenvironment including increased proteolysis, inflammatory dysregulation, and impaired neovascularization prevent timely resolution of chronic diabetic ulcers. It is hypothesized that augmentation of local wound microenvironment with a stable provisional matrix formed by proteolysis-resistant angiogenic peptide nanofibers (NFs) will create permissive environment for attenuated inflammation, enhanced neovascularization, and improved diabetic wound healing. Using murine excisional wound healing models, full-thickness dorsal skin wounds were treated with either NFs or control solutions (phosphate buffered saline; hyaluronic acid) and analyzed for morphology, inflammatory response, neovascularization, and biomechanical properties. NF treatment of diabetic wounds stimulated formation of a robust pro-angiogenic in situ tissue-engineered provisional matrix leading to a significant decrease in wound inflammatory cell infiltration and proinflammatory interleukin-6 levels, a significant increase in endothelial and endothelial progenitor cell infiltration, vascular endothelial growth factor levels, and neovascularization (day 7), as well as improved wound morphology, accelerated wound closure, and significantly stronger repair tissue (day 28). These results suggest that appropriate design of provisional matrix may compensate for some of the complex disruptions in diabetic wound microenvironment and provide missing cues to cells and direct in situ responses toward improved healing, which is promising for future development of new therapies for diabetic ulcers.     

Adenoviral mediated gene transfer of PDGF-B enhances wound healing in type I and type II diabetic wounds

We have shown that the genetically diabetic mouse (C57BLKS/J-m+/+Lepr(db)) has a wound healing and neovascularization deficit associated with an inability to recruit endothelial precursor cells (EPCs) to the wound. This may account for a fundamental mechanism in impaired diabetic wound healing. We hypothesized that the adenoviral mediated overexpression of platelet-derived growth factor-B (PDGF-B) would enhance wound healing, improve neovascularization, and recruit EPCs to the epithelial wound in three diabetic mouse models. Eight-mm full-thickness flank wounds were made in db/db, nonobese NOD/Ltj, streptozotocin, and C57BLKS/J mice. Wounds were treated with either 1 x 10(8) PFU Ad-PDGF-B or Ad LacZ or phosphate buffered saline solution. Wounds harvested at seven days were analyzed for epithelial gap, blood vessel density, granulation tissue area, and EPCs per high powered field. All three diabetic models have a significant wound healing and neovascularization defect compared to C57BLKS/J controls. Adenoviral-PDGF-B treatment significantly enhanced epithelial gap closure in db/db, streptozotocin, and nonobese NOD/Ltj mice as compared to diabetic phosphate buffered saline solution or Ad LacZ controls. A similar increase in the formation of granulation tissue and vessel density was also observed. All three models had reduced levels of GATA-2 positive EPCs in the wound bed that was corrected by the adenoviral mediated gene transfer of PDGF. EPC recruitment was positively correlated with neovascularization and wound healing. Three different diabetic models have a wound healing impairment and a decreased ability to recruit EPCs. The vulnerary effect of adenoviral mediated gene therapy with PDGF-B significantly enhanced wound healing and neovascularization in diabetic wounds. The PDGF-B mediated augmentation of EPC recruitment to the wound bed may be a fundamental mechanism of these results.