Comparison of solvent-dehydrated allograft dermis and autograft rectus fascia for pubovaginal sling: questionnaire-based analysis

Objectives To evaluate the efficacy of pubovaginal sling using human cadaveric dermis processed by solvent dehydration and compare results to those of another group in which autograft rectus fascia was used. Material and methods The efficacy of autologous rectus fascia (group 1, n = 25) or solvent-dehydrated cadaveric dermis (group 2, n = 24) for pubovaginal sling were compared in women with stress urinary incontinence (SUI). Surgical outcome, patient satisfaction and quality of life was assessed by the urogenital distress inventory (UDI-6) and the incontinence impact questionnaire (IIQ-7). Results Mean follow-up for patients in group 1 and group 2 were 18 and 13 months, respectively. Our questionnaire-based assessment revealed that SUI was either cured or improved in a total of 21 (84%) patients in group 1 and 19 (79%) patients in group 2. No statistically significant difference was found for the overall success (P < 0.05) and no major complications were encountered in both groups. Conclusions Use of allograft dermis as an alternative to autologous rectus fascia for pubovaginal sling had comparable improvement in patient satisfaction and quality of life at intermediate term.     

The use of glandular-derived stem cells to improve vascularization in scaffold-mediated dermal regeneration

Clinical success in tissue regeneration requires improvements in vascularization capacity of scaffolds. Several efforts have been made in this field including cellular and acellular technologies. In this work we combined the use of stem cells derived from pancreas or submandibular glands expressing green fluorescent protein (GFP⁺) with a commercially available scaffold for dermal regeneration. Cells were isolated, characterized and seeded in a scaffold for dermal regeneration. Scaffolds containing cells were used to induce dermal regeneration in a full skin defect model. After 3 weeks of in vivo regeneration, tissues were harvested and vascularization was analyzed. Results showed that gland-derived stem cells displayed stem cell features and presented multipotential differentiation capacity because they were able to differentiate in cell types representing the 3 different germ layers. After seeding, cells were homogeneously distributed and formed focal adhesions with the scaffold. Metabolic assays showed that cells can be cultured for at least 3 weeks in the scaffold. In vivo, the presence of pancreatic or submandibular stem cells significantly enhanced the vascularization compared to empty scaffolds. Presence of gland-derived stem cells in the regenerating tissue was confirmed by the detection of GFP expression in the wound area. In order to explore the possible mechanisms behind the improvement in vascular regeneration, in vitro experiments were performed, showing that gland-derived stem cells could contribute by angiogenic and vasculogenic mechanisms to this process. Our results suggest that the combined use of stem cells derived from glands and scaffold for dermal regeneration could be a rational alternative to improve vascularization in scaffold-mediated dermal regeneration.     

Surgical anatomy of the skin

The skin is the largest organ in the body and forms the interface between the body and the environment. Its structure is highly adapted to protect the body from many forms of noxious agents, to maintain homeostasis in several physiologic domains and to allow the individual to appreciate various modalities of sensation. The skin is divided into three layers – the epidermis, dermis and hypodermis or (subcutaneous fat). The epidermis is a continually regenerating structure formed mainly from keratinocytes which account for the majority of cells in the epidermis. The pigment melanin, produced in the melanocyte cells of the epidermis is a major factor in determining skin colour. The dermis supports and gives strength and flexibility to the epidermis. It contains multiple blood vessels, lymphatics and nerves within its connective tissue architecture. The hypodermis is composed of various amounts of subcutaneous fat which plays a role in thermoregulation and water storage. It is essential that surgeons have a good knowledge of the structure of skin in order to choose the optimum site for surgical incisions, to understand the best methods of wound closure and to anticipate potential problems with wound healing.     

复方壳多糖真皮替代物体外抗菌作用的研究

目的 研究复方壳多糖真皮替代物对金黄色葡萄球菌、铜绿假单胞菌、大肠埃希菌、白念珠菌的体外抑菌作用。方法 制备复方壳多糖真皮替代物和复方胶原凝胶真皮,分别为实验组和对照组,各取50μL滴加在涂满细菌或真菌的平板,每种菌实验组和对照组样本各6个,孵育24h后观察抑菌环。结果 复方壳多糖真皮替代物对金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌具有抑菌作用,抑菌环均大于复方胶原凝胶真皮替代物,差异有统计学意义。两组对白念珠菌无抑菌作用。结论 复方壳多糖真皮替代物是有体外抗细菌作用的组织工程产品。     

胎牛血清促进色素上皮衍生因子在皮肤角质形成细胞和成纤维细胞中的表达

目的:探讨表皮角质形成细胞和真皮成纤维细胞中色素上皮衍生因子(PEDF) 表达的影响因素.方法:体外培养角质形成细胞和成纤维细胞,并以10%FBS(胎牛血清)刺激,通过免疫荧光和Western blot检测PEDF的表达.结果:PEDF大多位于细胞浆中,但在细胞核中也有少量表达.细胞浆中PEDF并非均质型分布,而是呈细颗粒状集聚.10%FBS促进角质形成细胞和成纤维细胞中PEDF的集聚和表达,而且这一分布形式不受组胺和佛波肉豆蔻醋酸(PMA) 的影响.结论:10% FBS促进角质形成细胞和成纤维细胞中PEDF的集聚和表达.     

口内切口联合耳后真皮-脂肪游离移植治疗微小唇裂

目的 探讨一种修复微小唇裂的方法.方法 在患侧人中嵴对应的黏膜侧做口内切口,将口轮匝肌解剖复位;在患侧上唇通过皮下隧道游离移植,从耳后切取的真皮一脂肪形成人中嵴;红、白唇交界处用Z成形术等方法修复,红唇凹陷用耳后真皮-脂肪游离移植充填;患侧鼻畸形采用悬吊固定等方法矫治.结果 共治疗8例,7例获随访,最长18个月,均取得满意效果.结论 口内切口联合耳后真皮一脂肪游离移植治疗微小唇裂是一种理想方法.     

大鼠真皮间充质干细胞的体外长期培养及胶原海绵对其生长的影响

从新生大鼠真皮细胞中分离多能干细胞，体外长期传代培养，观察细胞形态和超微结构的变化。检测细胞增殖和分化能力的改变及胶原基质对细胞生长的影响。揭示体外长期传代培养对大鼠真皮间充质干细胞生物学性状的影响，结果表明；大鼠真皮组织中的间充质干细胞体外培养至180d，传至25代的细胞仍具有干细胞的特征；形态的均一，细胞核结构原始，细胞器不发达；体外增殖迅速，保持了向成骨细胞和软骨细胞分化的潜能，胶原基质成分可促进细胞的生长，而胶原海绵支架更利于细胞的三维生长。结论是体外长期传代培养后大鼠真皮间充质干细胞仍保持良好的干细胞特性，为真皮间充质干细胞的深入研究与应用提供了实验依据。     

Depilatory creams increase the number of hair follicles,and dermal fibroblasts expressing interleukin-6, tumor necrosis factor-α, and tumor necrosis factor-β in mouse skin

Besides using for hair removal, depilatory agents have been considered to be used as a penetration enhancer for transepidermal drug delivery. To examine the effect in hair follicles (HFs), two commercially available depilatory creams were tested on the dorsal skin of mice to monitor the effect deep into the skin structure. Fifteen male BALB/c mice were used in this study. Depilatory creams were applied to the dorsal skin of the same animal using shaved and untouched treatments as controls to minimize individual differences. Skin samples were collected at three days, one week and two weeks (n = 5 for each) after the treatment, and subjected for hematoxylin-eosin staining, and immunohistochemical analysis for proinflammatory cytokines. The morphological examination showed an increase in the thickness of epidermal layer of the depilatory cream-treated skin at early time points and in the subcutis at two weeks. Depilatory cream promoted entry of anagen phase and increased the number of hair follicles in the subcutis at one and two weeks. Immunohistochemistry showed elevated percentages of dermal fibroblasts expressing interleukin-6, tumor necrosis factor-α, and tumor necrosis factor-β. Shaving process increased the thickness of epidermis and dermis as depilatory creams did, but did neither induce the expression of proinflammatory cytokines in the dermal fibroblasts nor the number of HFs. The results suggested that the commercially available depilatory creams caused a transient minor inflammatory response of the skin and increased the levels of cytokines that might subsequently affect hair growth.     

巢蛋白在人真皮成纤维细胞中的表达

目的探讨巢蛋白(nestin)在人皮肤真皮组织成纤维细胞(adu lt hum an derm is fibrob lasts,HDF)中的表达。方法采用体外培养、免疫组织/细胞化学技术检测巢蛋白在6例成人皮肤真皮组织及体外培养3、5、7、10、12代龄皮肤真皮成纤维细胞中的表达,计数分析人皮肤真皮组织成纤维细胞中巢蛋白+成纤维细胞数量,权重法分析体外培养成纤维细胞各代间巢蛋白的表达差异。结果人皮肤真皮组织中,巢蛋白+成纤维细胞表达数量占成纤维细胞总数(9.5±3.0)%,其数量为(103.3±67.4)个/mm2。与人皮肤真皮组织巢蛋白+成纤维细胞的表达数量相比,体外培养的真皮成纤维细胞中巢蛋白+成纤维细胞数量明显升高,并出现代龄之间的差异(P<0.05),其中第7、10代细胞表达量高于第5、12代细胞,第3代细胞最少(P<0.05)。结论在人皮肤真皮组织成纤维细胞中存在着巢蛋白+成纤维细胞。体外培养条件下,人皮肤真皮巢蛋白+成纤维细胞数量增加,提示体外培养作为刺激因子可能使成纤维细胞反分化为其前体细胞,作为干细胞标志物的巢蛋白有可能成为用于成纤维前体细胞鉴定的标志物之一。