ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30401.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30403.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1997.50303.x-i4

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

摘要:

Of the myriad of growth factors examined for their ability to accelerate or improve tissue repair, none has as broad a spectrum of action as that of TGF‐β. In the 10 years since the first description of its ability to enhance wound healing, tremendous advances have been made in understanding the basis of its action in tissue repair. It is released from activated platelets and can both act on and be secreted by each of the diverse cell types which participate in the healing process. Actions of TGF‐β to stimulate chemotaxis, fibrogenesis, angiogenesis, and autoinduction of its expression are mediated by signalling through a unique set of serine‐threonine kinase receptors which distinguish it mechanistically from other growth factors with activities in wound healing. Both topical and systemic administration of TGF‐β have been shown to improve healing in a variety of animal models of both normal and impaired healing at dermal as well as nondermal sites such as bone, intestine, the eye, or

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30405.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

摘要:

Restoration of the epidermal barrier is a requirement for burn wound closure. A rapid, reliable, and noninvasive measure of the rate of restoration of the epidermal barrier is not readily available. To monitor the reformation of the epidermal barrier, we measured surface electrical capacitance on cultured skin substitutes (human keratinocytes and fibroblasts attached to collagen‐glycosaminoglycan substrates) and split‐thickness skin autografts grafted to patients. Data were collected from four patients with burns and one pediatric patient with a congenital hairy nevus comprising>60% total body surface area. Capacitance measurements were performed at days 7, 10, 12, 14, and 28 by direct contact of the capacitance probe for 10 seconds to the cultured skin substitutes or split‐thickness autograft. On postoperative days 7, 10, 12, 14, 21, and 28, the surface electrical capacitance of cultured skin substitutes after 10 seconds of sampling was 2468 ± 268, 1443 ± 439, 129 ± 43, 200 ± 44, 88 ± 20, and 74 ± 19 picofarads (mean ± standard error of the mean), respectively. Surface electrical capacitance for split‐thickness autograft on the same days was 1699 ± 371, 1914 ± 433, 125 ± 16, 175 ± 63, 110 ± 26, 271 ± 77 picofarads, respectively. Surface electrical capacitance in all of the grafts decreased with time. Cultured skin substitutes had approximately the same 10‐second capacitance values as split‐thickness autograft during 3 weeks of healing and approached values for uninjured skin (32 ± 5 picofarads) by 12 days. Measurement of surface electrical capacitance is a direct, inexpensive, and convenient index for noninvasive monitoring of ep

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30406.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

摘要:

In this article, we initially review several problems associated with the design and interpretation of certain types of experiments currently used to study wound healing, drawing attention to the fact that applications for standard statistical techniques in the analysis of the experimental results are often of limited value. We then argue that, because of the special nature of wound healing data, curve fitting of empirical model equations can often provide a convenient way to summarize treatment effects with large data sets. The various ways in which this technique could be used to facilitate the interpretation of experimental wound healing results are then explored. To illustrate this approach, we then took several wound healing experiments and introduced possible models that could be used, paying particular attention to simple equations with the smallest possible number of parameters. For each equation, the way that the parameters of the model could be interpreted with regard to the biologic effects represented is given. Examples are given to show the application of each model discussed theoretically in the interpretation of some typical experimental data sets.

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30407.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

摘要:

Vibriolysin, a new agent for enzymatic debridement, was recently shown to rapidly and thoroughly hydrolyze burn wound eschar within full‐thickness wounds. The safety of this agent and its subsequent effect on wound healing processes have yet to be established and are addressed in this study. Within the context of a porcine partial‐thickness burn wound model, the enzyme was shown to digest desiccated eschar after two applications, whereas four applications of another enzymatic preparation were required. Computerized morphometric analysis of dermal and epidermal growth from histologic sections on wounds harvested at day 7 and 10 was used to assess wound healing. The data indicate that wounds treated with Vibriolysin exhibited significant dose‐responsive stimulation of granulation tissue (neodermis) as compared with control treatment groups. Repeated protease applications did not convert partial‐thickness burns to full‐thickness wounds, and no adverse inflammatory responses were detected between 1 and 10 days. The results suggest that in addition to its documented efficacy in the debridement of burn eschar, Vibriolysin may have beneficial effects on dermal reparati

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30408.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

摘要:

We have previously shown a population of putative mesenchymal stem cells in the connective tissue surrounding embryonic avian skeletal muscle. These cells differentiate into at least five recognizable phenotypes in culture: fibroblasts, chondrocytes, myotubes, osteoblasts, and adipocytes. We have now isolated a similar population of cells from fetal and newborn rat skeletal muscle. Cells from rat leg muscle were dissected, minced, and then enzymatically digested with a collagenase‐dispase solution. The dissociated cells were plated and allowed to differentiate into two recognizable populations: myotubes and stellate mononucleated cells. The cells were then trypsinized, filtered through a 20 µm filter to remove the myotubes, frozen at −80° C, then thawed and replated. In culture the cells maintained their stellate structure. However, under treatment with dexamethasone, a nonspecific differentiating agent, seven morphologic conditions emerged: cells with refractile vesicles that stained with Sudan black B (adipocytes), multinucleated cells that spontaneously contracted in culture and stained with an antibody to myosin (myotubes), round cells whose extracellular matrix stained with Alcian blue, pH 1.0 (chondrocytes), polygonal cells whose extracellular matrix stained with Von Kossa's stain (osteoblasts), cells with filaments that stained with an antibody to smooth muscle a‐actin (smooth muscle cells), cells that incorporated acetylated low density lipoprotein (endothelial cells), and spindle‐shaped cells that grew in a swirl pattern (fibroblasts). The initial population is tentatively classified as putative mesenchymal stem cells. The presence of these cells point to the existence of stem cells in the postembryonic mammal that could provide a basis for tissue regeneration as opposed to scar tissue formation during woun

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30409.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

摘要:

Despite clinical and experimental reports of digit tip regrowth, bone regrowth after amputation through terminal phalanges has not been methodically documented. We have examined bone regrowth in mice after amputation through the terminal phalanx to determine how the level of amputation affects the response and whether the response varies between adults and neonates. Digit tips were amputated, and, at selected intervals greater than 5 weeks after amputation, digits were photographed and processed for whole mount staining with alizarin red stain. Amputations within the distal 40% of the terminal phalanx yielded grossly normal digits within 5 weeks and bone regrowth which usually attained or surpassed the original length. Amputations through the proximal 20% of the distal phalanx precluded nail plate regrowth, and bone grew minimally or regressed. Amputation through the intermediate 40% of the distal phalanx produced digit tips in which bone regrowth was correlated with nail regrowth and in which bone regrowth did not reach original levels. The response in adults and neonates was similar. The correlation between nail regrowth and bone regrowth may help to predict phalangeal bone regrowth after amputation in adults and juveniles.

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30410.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY

摘要:

In many species, open cutaneous fetal wounds do not heal in utero. Such open wounds have been shown to close only after their exclusion from amniotic fluid, thus leading to the hypothesis that amniotic fluid inhibits open wound healing. Therefore the effect of amniotic fluid exposure on the healing of open fetal skin wounds was studied. Fetuses of New Zealand White rabbits received a full‐thickness circular 4 mm diameter skin punch biopsy wound. Wounds were left uncovered, covered with a latex patch, or covered with a latex patch with a central hole (doughnut). This third group provided for wound exposure to amniotic fluid while controlling for any wound splinting effect of the patch. Wounds were harvested after 5 days, the wound area was determined planimetrically, and wound edges were examined by means of light microscopy. Analysis of glycosaminoglycans in the wound extra‐cellular matrix was performed on a separate group of wounds treated similarly. Uncovered wounds enlarged by an average of 60%, whereas wounds covered with the doughnut patch enlarged by an average of 24%. In contrast, the wounds in the patch‐covered group decreased in size by an average of 84%. Histologically all groups contained proliferating fibroblasts and epithelial migration at the wound edge but also an absence of granulation tissue. The patch‐covered wounds, which had decreased wound area, were significantly enriched in hyaluronic acid. These results suggest that the healing of the patch‐covered wounds occurs without the formation of granulation tissue, presumably through a process of cellular migration and proliferation and that healing was inhibited by exposure to amniotic fluid. Hyaluronic acid has been shown to be permissive of cellular migration and to play a key role in tissue regeneration. Therefore, we speculate that direct exposure of open wounds to amniotic fluid during the late stages of fetal development in the rabbit prevents hyaluronic acid deposition, which in turn may alter woun

ISSN:1067-1927    

DOI:10.1046/j.1524-475X.1995.30411.x

出版商:Blackwell Science    

年代:1995

数据来源: WILEY