创面异体移植培养表皮细胞后存活的判定

应用４种方法判定烧伤创面异体移植的培养表皮细胞存活情况：１．聚合酶链反应（ＰＣＲ）查Ｙ染色体特异性ＤＮＡ片段；２．ＰＣＲ扩增ＰＭＣＴ１１８长度多态性基因位点；３．ＰＣＲ／ＳＳＯＨＬＡ－ＤＱａ分型；４．ＤＮＡ指纹。共检测１６例病人的２７个活检标本，均证实有供者的ＤＮＡ，最长时间为移植后９２天。初步实验结果表明：培养表皮异体移植后可存活较长时间。     

Differentiation of the epidermis in turtle: an immunocytochemical, autoradiographic and electrophoretic analysis

Proteins involved in the process of cornification of turtle epidermis are not well known. The present immunocytochemical, electrophoretic and autoradiographic study reports on the localization patterns and molecular weights of keratins, which are cornification proteins, and of tritiated histidine in turtle epidermis. Alpha-keratins with a molecular weight of 40-62 kDa are present in the epidermis. Beta-keratin is mainly detectable in the stratum corneum of the carapace and plastron, but is rarely present or even absent in the corneous layer of limb, tail and neck epidermis. After electrophoresis and immunoblotting with an antibody against chicken scale beta-keratin, bands at 15-17, 22-24, and 36-38 kDa appeared. This antibody recognized weaker bands at 38-40 and 58-60 kDa in the soft epidermis. After reduction and carboxymethylation of proteins extracted from carapace and plastron, but not of proteins from the soft epidermis, protein bands at 15-17 and 35-37 kDa were found when using the anti-beta 1-keratin antibody. Loricrin-, filaggrin-, sciellin-, and transglutaminase-like immunostaining was detectable only in the transitional and lowermost corneous layers of the soft epidermis. Vesicular bodies in the transitional layer were immunolabeled by the anti-loricrin antibody, and weakly by the anti-filaggrin and anti-transglutaminase antibodies. In immunoblots, the anti-loricrin antibody reacted with a major band at 50-54 kDa in both carapace-plastron and soft epidermis. The anti-sciellin antibody detected major bands at 38-40 and 50 kDa in hard epidermis, and at 50 and 54-56 kDa in soft epidermis. Filaggrin-like immunostained bands were observed at 50-55 and 62-64 kDa. This immunostaining was probably due to a common epitope in filaggrin and some keratins. Histidine was evenly incorporated in the epidermis, and the ultrastructural study showed random labeling, often associated with keratin bundles of alpha and beta-keratinocytes. Histidine-labeled protein bands were not found in the carapace-plastron. In the soft epidermis, weakly labeled bands at 15-20, 25, and 45-60 kDa were found occasionally. The latter bands probably represented neo-synthesized keratins as was also indicated by the ultrastructural autoradiographic analysis. In conclusion, our study suggests that proteins with epitopes that they have in common with cornification proteins of mammalian epidermis are also present in the epidermis of turtle.     

Epidermal lipid in several cetacean species: ultrastructural observations

The ultrastructure of the skin of four cetacean species, bottlenose dolphin (Tursiops truncatus) long-finned pilot whale (Globicephala melaena), humpback whale (Megaptera novaeangliae), and fin whale (Balaenoptera physalus) was investigated with particular reference to epidermal lipid. It has already been established that massive lipid reservoirs exist in whales, that the biochemical structures of cetacean lipids are unique, and that unusual intracellular lipid droplets appear in the epidermis. We report here some novel findings on scanning electron microscopic morphology of epidermal lipid, and on its ultrastructural morphology in general and specialized integumentary sites, including species not previously investigated. The intracellular epidermal lipid droplets were more extensive than lamellar body-derived intercellular lipid which is within the interstices of stratum externum cells. The intracellular droplets were spherical, highly variable in size ranging from 0.24 m to 3.0 m in diameter, appeared singly or were aggregated in cytoplasmic cavitations, and often were closely associated with epidermal cell nuclei. Evidence for exocytosis of the intracellular droplets was not observed. Significant numbers of intracellular lipid droplets are not observed in the epidermis of terrestrial mammals, so their presence is one of several aquatic specializations of the cetacean integument. Its full significance remains obscure, but it is more probably associated with epidermal cell metabolism than with secretion of lipid.     

皮肤角朊细胞与表皮干细胞双向电泳图谱的建立及差异分析

目的 建立皮肤角朊细胞与表皮干细胞的双向电泳图谱,并分析二者表达蛋白质的差异,为进一步研究体外调控表皮十细胞的增殖、分化提供线索.方法酶消化法获取单个表皮细胞悬液.Ⅳ型胶原快速贴壁法分选表皮干细胞.利用舣向电泳技术(2-DE)建立两种细胞的蛋白质表达图谱,并用Imagemaster 2D elite 5.0软件分析两种细胞的差异表达蛋一点.结果两种细胞的2-DE蛋白表达谱具有良好的重复性和可比性.皮肤角朊细胞与表皮干细胞的电泳图谱平均蛋白质点数分别为(982 ±18)个和(930 ±15)个,匹配点数为(850±13)个和(798±11)个,匹配率是86.56%和85.81%;两种细胞蛋白质间匹配点数是(886 ±8)个,匹配率是76.98%.找到差异蛋白点11个,其中只在表皮下细胞中表达或高表达的有8个;只在皮肤角朊细胞中表达或高表达的有3个.结论利用双向电泳法得到了分辨率较高儿重复性好的皮肤角朊细胞与表皮干细胞蛋白质组图谱,且二者存在有一定的差异.     

Freeze-fracture study of melanosomes in mammalian epidermis and the distribution of intramembrane particles in the melanosome membrane

Summary The ultrastructure of melanosomes in mammalian epidermis has been studied using the freeze-fracture technique. The internal structure of the melanosome, as seen in cross-fractured granules, consists of a very fine particulate matter. There is no evidence of an internal membranous structure in melanosomes, indicating that the internal matrix which is characteristic of ultrathin sectioned material most likely represents cross-linked protein fibers.Fracture en-face of the melanosome limiting membrane reveals a random distribution of intramembrane particles on both the P- and E-faces of the membrane. There is a significantly higher density of IMPs on the P-face. The IMPs of the melanosome membrane may be involved in (a) selective passage of ions through the membrane, (b) membrane transducing events, and/or (c) anchoring sites for cytoplasmic fibrils and microfilaments.Research supported by USPHS Grant AM-20669 from the National Institute of Arthritis, Metabolism, and Digestive Diseases     

巧用医用胶喷雾瓶盛装丁卡因表麻药

临床上常用喉头喷雾器盛装配制好的丁卡因表麻药。传统喷雾器为50ml容器,在装少于10ml时喷不出,一般一个病人实际用量为3～5ml,故要配制成15ml左右方够一个病人使用。丁卡因用于咽喉表麻的浓度为1%～2%,一支50mg丁卡因粉剂,用2.5～5ml盐水配制,需要至少3支丁卡因粉剂,与一个病人实际用量相比,造成了药液浪费及增加对喷雾器的清洗、消毒     

Cells of origin and tumor-initiating cells for nonmelanoma skin cancers

The epidermis of the skin is a multilayered stratified epithelium whose primary function is to provide a barrier against our external environment. As a result, cells in the epidermis are subject to constant assault from environmental pathogens, many of which can cause deleterious mutations. However, most of these mutations do not lead to skin cancer. One explanation is that most genetic hits are sustained by mature or transit cells with limited proliferative capacity and only stem cells that acquire genetic alterations have the potential to propagate a frank tumor. In this mini-review we will discuss recent studies that provide some of the first genetic evidence to support a stem cell origin for a number of skin cancer types.     

Induction of Hyaluronan Cables and Monocyte Adherence in Epidermal Keratinocytes

Hyaluronan attached to cell surface can form at least two very different structures; a pericellular coat close to plasma membrane and hyaluronan chains coalesced into “cables” that can span several cell lengths. The hyaluronan in cables, induced by many inflammatory agents, can bind leukocytes, whereas that in the pericellular coat does not contribute to leukocyte binding. Therefore, this structural change seems to have a major role in inflammation. In the present study we checked whether cells of squamous epithelium, like epidermal keratinocytes, can form hyaluronan cables and bind leukocytes. In addition, we checked whether hyaluronan synthesis is affected during the induction of cables. Control keratinocytes expressed pericellular hyaluronan as small patches on plasma membrane. But when treated with inflammatory agents or stressful conditions (tunicamycin, interleukin-1β, tumor necrosis factor-α, and high glucose concentration), hyaluronan organization changed into cable-like structures that avidly bound monocytes. Simultaneously, the total amount of secreted hyaluronan was slightly decreased, and the expression levels of hyaluronan synthases (Has1–3) and CD44 were not significantly changed. The results show that epidermal keratinocytes can form cables and bind leukocytes under inflammatory provocation and that these effects are not dependent on stimulation of hyaluronan secretion.     

Oxidative stress-dependent MMP-13 activity underlies glucose neurotoxicity

Background

A complication of diabetes is neuropathy, a condition of sensory axon degeneration that originates in the epidermis. The mechanisms remain unknown but reactive oxygen species (ROS) have been implicated in this condition. In this study, we assessed the role of ROS and a candidate downstream target, MMP-13 in glucose-induced sensory axon degeneration in zebrafish and mice.