进一步重视脂肪新功能对创面愈合作用的研究

创面愈合的研究范围正随着相关领域的研究进展而不断拓展和完善.以皮下脂肪组织为例,以往大多数的研究认为,脂肪组织来源于间充质细胞(mesenchymal cell,MC),其功能仅是一个能量贮存仓库.但近年来的研究表明,脂肪组织还可能是一个重要的内分泌器官,在发育学、信号转导以及干细胞作用等诸多方面与组织修复存在着密切联系.有专家认为,加强对脂肪细胞新功能的研究和开发有可能对创面修复和组织再生机制产生新的认识和寻找出新的促愈合手段.     

脂肪与创面愈合

目的 探讨脂肪组织与创面愈合的关系。方法 通过对近期文献的回顾，脂肪组织参与食物摄入、能量代谢等生理过程。通过内分泌、自分泌和旁分泌参与创面愈合的调节。结果 脂肪组织主要分泌的几种因子：瘦素、细胞因子、生长因子和脂质等参与创面愈合过程。结论 脂肪组织在创面愈合过程中可能具有重要作用，进一步了解脂肪细胞与上皮形成间的关系有助于揭示创面愈合的机制。     

脂肪与创面愈合

创伤愈合是一个复杂的生物学过程,创面愈合的过程分为炎症反应、肉芽组织形成、再上皮化及伤口闭合后塑形三个阶段,是一个有序的变化过程.而许多重要的步骤都需要以营养为基础,不同的营养水平将影响代谢和生理过程.     

脂肪干细胞对创面愈合作用的研究进展

创面愈合是由多种细胞及细胞因子参与的复杂过程,难愈或不愈创面是整形外科的一大挑战.随着人们对脂肪干细胞基础研究及临床应用研究的深入,利用脂肪干细胞来提高创面愈合已被证明是一种非常有前景的治疗策略.在此就脂肪干细胞促进创面愈合的机制、治疗策略的改进、细胞移植途径及临床应用研究等方面的进展进行综述.     

adiponectin对脂肪组织创面愈合作用的体外实验研究

目的:探讨脂肪组织创面愈合(ATWH)的发生机制。方法:体外培养小鼠3T3-L1前脂肪细胞系,应用免疫组化及RT-PCR法检测3T3-L1前脂肪细胞脂联素受体(AdipoR1/2)的表达,用Elisa法测定3T3-L1前脂肪细胞自身分泌脂联素(adiponectin)的浓度,应用MTT和体外伤口愈合模型研究不同浓度adiponectin对前脂肪细胞增殖和迁徙的作用。结果:AdipoR1/2可在3T3-L1前脂肪细胞中表达,不同密度的3T3-L1前脂肪细胞分泌的adiponectin浓度差异无统计学意义(P0.05),adiponectin能够促进3T3-L1前脂肪细胞的增殖和迁徙。结论:adiponectin可能通过促进前脂肪细胞的增殖和迁徙促进ATWH,全身或局部应用adiponectin可能是促进外科切口愈合的有效治疗方法。     

重视烧伤后补锌,促进创面愈合

烧伤创面始终是烧伤治疗的焦点，创面愈合一直是烧伤治疗的目标。影响创面愈合的诸多因素己被普遍关注，但有关微量元素锌与创面愈合的关系论述欠丰。近年来大量研究证实，严重烧伤后普遍缺锌，除对整体产生不良影响外，还使创面愈合延迟。补锌确有改善锌营养状态，促进创面修复之功效。 一、锌在创面愈合中的作用 成人体内约含锌１．４－２．３ｇ，在各微量元素含量中仅次于铁，居第二位［１］。其中皮肤锌即占体内锌总量的２０％，表皮含锌量明显多于真皮，表皮为７０．５ ｇ／ｋｇ干重，真皮为 １２．６ ｇ／ｋｇ干重，表明锌是维持皮肤…     

创面愈合评价指标进展

目的：建立客观,准确地评价创面愈合的标准。方法：对近年来国内外有关文献进行检索,总结。结果：筛选了创面愈合率,创面愈合时间,组织病理学分析,巨噬细胞定量分析,羟脯氨酸含量测定,细胞增殖情况,细胞DNA含量和细胞周期分析,转化生长因子－α水平,白细胞介素－1,白细胞介素－6和肿瘤坏死因子水平,角质细胞胶原酶－1含量测定,成纤维细胞生长因子受体－1水平,单核细胞化学诱导蛋白－1水平和角质细胞纤溶酶源活化抑制剂－2水平等十三种创面愈合评价指标。结论：创面愈合率,创面愈合时间及组织病理学分析仍是最直接而有效的创面愈合评价指标。     

创伤膏对创面愈合的作用

目的:观察创伤膏在创面愈合中的作用。方法:将63例患者随机分为两组。治疗组常规换药,创面涂抹创伤膏;对照组常规换药。比较两组的治愈率、总有效率、创面愈合时间、创面缩小率、症状体征、创面分泌物细菌培养以及组织学观察的差异。结果:用药4周后,总体疗效、创面愈合时间、创面缩小率和抑菌作用治疗组优于对照组(P<0.05)。结论:创伤膏能够提高创面修复质量,缩短创面愈合时间。     

烧伤创面愈合

本文重点阐述有关原理。并讨论组织修复和创面愈合。有关热力损伤内容原则上各种原因烧伤。     

成纤维细胞生长因子对手术创面愈合的作用

本文介绍成纤维细胞生长因子的作用机理及对手术创面愈合的任用，并探讨了在临床上的应用价值。     

脂肪来源干细胞在皮肤组织损伤修复中的表型和功能变化

目的:通过模拟皮肤损伤修复过程中局部微环境的变化,了解脂肪来源干细胞(adi pose t i ssue deri ved st em,cAeSCl)l的表型改变对细胞功能的影响。方法:由手术废弃皮肤和脂肪组织获取实验所需细胞,并培养扩增。对不同传代数的ASC细胞进行脂肪细胞诱导分化,了解细胞的可诱导分化性能;构建ASC细胞-胶原凝胶,贴壁或悬浮培养,对ASC凝胶进行α-SMA免疫组化染色;培养基中添加TGF-β1,观察TGF-β1对ASC细胞表型和可诱导分化能力的影响;收集培养上清液,El i sa法测定比较成纤维细胞和ASC细胞的细胞生长因子分泌水平,以及经TGF-β1作用,ASC细胞表型发生变化后细胞生长因子分泌水平的变化。结果:ASC细胞可以多次传代,仍保持较好的可诱导分化特性;在培养过程中,张力和TGF-β1可以使ASC获得α-SMA阳性表型;ASC细胞相比成纤维细胞,有较高的VEGF和KGF分泌水平,但TGF-β1分泌水平极低(未测到),获得α-SMA阳性表型的ASC细胞的VEGF分泌水平继续大幅上升,而且也分泌了较高水平的TGF-β1。结论:ASC细胞在创伤局部环境的刺激下或经体外人工诱导,可以产生更有利于创伤愈合的表型。对ASC细胞特性的了解和调控,将有利于ASC细胞在组织修复再生方面的应用。     

Diabetes impairs adipose tissue–derived stem cell function and efficiency in promoting wound healing

Adipose tissue–derived stem cells (ASCs) are gaining increasing consideration in tissue repair therapeutic application. Recent evidence indicates that ASCs enhance skin repair in animal models of impaired wound healing. To assess the therapeutic activity of autologous vs. allogeneic ASCs in the treatment of diabetic ulcers, we functionally characterized diabetic ASCs and investigated their potential to promote wound healing with respect to nondiabetic ones. Adipose tissue–derived cells from streptozotocin‐induced type 1 diabetic mice were analyzed either freshly isolated as stromal vascular fraction (SVF), or following a single passage of culture (ASCs). Diabetic ASCs showed decreased proliferative potential and migration. Expression of surface markers was altered in diabetic SVF and cultured ASCs, with a reduction in stem cell marker‐positive cells. ASCs from diabetic mice released lower amounts of hepatocyte growth factor, vascular endothelial growth factor (VEGF)‐A, and insulin‐like growth factor‐1, growth factors playing important roles in skin repair. Accordingly, the supernatant of diabetic ASCs manifested reduced capability to promote keratinocyte and fibroblast proliferation and migration. Therapeutic potential of diabetic SVF administered to wounds of diabetic mice was blunted as compared with cells isolated from nondiabetic mice. Our data indicate that diabetes alters ASC intrinsic properties and impairs their function, thus affecting therapeutic potential in the autologous treatment for diabetic ulcers.     

A novel method of studying wound healing

In order to study wound healing, it is often necessary to administer various wound-active substances by the systemic route. It is unclear whether the observed effects are the result of local or systemic influence of the agent administered. Furthermore, high systemic doses are often required to achieve activity at the wound level. Direct intrawound administration of substances is traumatic and disruptive to the fragile wound environment and increases the risk of infection. We devised a system for continuous atraumatic delivery of substances directly to subcutaneously implanted polyvinyl alcohol sponges, an adaptation of a well-established model of wound healing. Sponge-catheter constructs were fashioned by feeding identical lengths of silicone catheters through two 40-mg sponge disks (on edge). The distal sponge was fixed 0.5 cm from the distal, ligated end of the catheter and centered over two 1-mm holes in the catheter tubing. The proximal sponge was fixed over nonperforated catheter with its edge 2 cm proximal from the close edge of the distal sponge. Each construct was connected to a mini-osmotic pump (infusion rate 1 microl/h) loaded with an appropriate infusate and inserted subcutaneously on the dorsum of anesthetized male Sprague-Dawley rats. Hydroxyproline (OHP) content of sponges, a measure of collagen deposition, was determined at 7 days postwounding. Infusion of India ink confirmed selective delivery to the distal sponge. Saline infusion alone significantly elevated OHP content compared to noninfused sponges (450 +/- 43 vs 328 +/- 36 microg OHP/100 mg sponge, P < 0.05). Infusion of S-methylisothiourea (a selective iNOS inhibitor, 84 microg/sponge/24 h) successfully inhibited NO production (35.9 +/- 3.1 vs 49.6 +/- 3.6 microM, P < 0.05) and decreased sponge OHP content (385 +/- 60 vs 568 +/- 70 microg OHP/100 mg sponge, P < 0.05) without the toxic side effect (i.e., weight loss) seen with systemic administration. Infusion of an adenoviral solution containing mouse iNOS cDNA resulted in successful transduction of wound cells demonstrating the ability to deliver genes to a healing wound model. The data demonstrate that manipulation of wound physiology is possible by local delivery of low doses of wound-active compounds to the wound site. This promises to be a powerful tool for the study of both normal and impaired wound healing.     

Current concepts in soft connective tissue wound healing

The strength and integrity of intact soft connective tissues are related to the forces which exist between collagen fibrils and these in turn appear to depend on collagen fibril size, density and architecture en masse. The genetic type of collagen, enzymic modifications to the collagen monomer and the proteoglycan environment all affect fibril size. Current evidence suggests that the restoration of tissue continuity and the early redevelopment of tissue strength following wounding are initially achieved by the formation of a myofibroblast-reticulin network which eventually disappears as the healing wound ages. The extent of this network defines the area in which repair tissue will be laid down and the network is equipped with the sensory apparatus to monitor the physical and chemical environment where healing is taking place and thus to direct the various facets of connective tissue synthesis outlined above. The maturation of the scar connective tissue matrix and the development of attachment between new and original connective tissues are simultaneous, related but independent processes. It takes some time before the weld is achieved by the same forces that hold connective tissue fibres together in intact tissues and the myofibroblast-reticulin network is replaced.     

Adipose tissue extract enhances skin wound healing

The main function of adipose tissue has been considered as storage of triglycerides. Adipose tissue was considered harmful for healing extensive and deep burns because of poor circulation and easy liquefaction in wound beds, which offer an excellent culture medium for bacteria. However, these traditional concepts have been challenged with the discovery of the endocrine function of adipose tissue. To investigate the effects of adipose tissue extract on wound healing, we created four 3.0 x 2.5 cm full-thickness wounds on each side of the back of male Wu Zhi Shan minipigs (n=6), for eight wounds in each animal. The wounds were randomly divided to receive normal saline (0.5 mL; controls), adipose tissue extract (1.5 g), basic fibroblast growth factor (50 U/cm(2)), and epidermal growth factor (50 U/cm(2)). Reduction in wound area and wound volume was accelerated with adipose tissue treatment as compared with growth factor or control treatment. The thickness of the regenerated epidermis and the number of new vascular nets were markedly increased in adipose tissue-treated wounds. Biopsy of adipose tissue-treated wounds showed enhanced expression of proliferation cell nuclear antigen (PCNA) and Factor VIII-related antigen, which indicated active cell differentiation and proliferation. In vitro study in rat tissue showed adipose tissue extracts stimulating skin growth. Bacteriology results showed no significant differences in amount or type of bacteria, whatever the treatment. These results may challenge the traditional concept that adipose tissue plays a negative role in wound healing and may offer direct evidence for encouraging the retention of adipose tissue in autologous skin grafting for skin wounds.     

Roles of cytokines in wound healing processes]

In recent years, a number of studies have revealed the importance of cytokines and growth factors in the wound healing process. Cytokines, such as epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), transforming growth factor (TGF) alpha 1 and interleukin (IL)-6, have been shown to exhibit the particular ability to stimulate keratinocyte proliferation. In addition, bFGF and TGF beta 1 not only facilitate the migration of monocytes, neutrophils, macrophages, and fibroblasts, but also play a role in the generation of granulation tissue. Cytokine modulation of the repair process in both transitory and chronic wounds remains a very important subject for investigation. In this study, the clinical application of cytokines or cytokine-promoting drugs which were combined with or without collagen matrix is discussed as well as perspectives on wound care in the future.