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At least 19 recordsLinked to original sources
PubMed2000

[Clinical use of acellular allogenic dermis or acellular porcine dermis with split-thickness autologous skin graft in 119 cases].

OBJECTIVE: To observe the effect of acellular allogenic dermis or acellular porcine dermis together with split-thickness autologous skin graft on coverage of deep burn wound and the wound of scar excision. METHODS: Acellular allogenic dermis or acellular porcine dermis produced by our unit, with split-thickness autologous skin graft, were used in repairing various wounds in 119 cases. The take rate of various wounds was compared, and the take rate of wounds in which autologous skin from different sites was used to cover either acellular allogenic dermis or acellular porcine dermis was also compared. Histological examination and follow-up were made in some cases. RESULTS: After tangential excision, eschar excision and scar excision, the wounds were covered with either allogenic acellular dermis or porcine acellular dermis and autologous split-thickness skin. The take rate was found to be (93.4 +/- 3.4)%, (92.1 +/- 4.6)%, (94.5 +/- 3.5)%, respectively. There was no a significant difference in take rate (P > 0.05). No significant difference in take rate between the transplantation of allogenic acellular dermis with autologous split-thickness skin and transplantation of porcine acellular dermis with autologous split-thickness skin was found (P > 0.05). When autologous split-thickness skin harvested from the trunk or extremities was used, the take rate was (93.1 +/- 4.8)%, (89.0 +/- 6.2)%, respectively, whereas the take rate was only about 70% - 80% when skin harvested from the scalp was used. The take rate was only about 40% when acellular allogenic dermis and autologous micro-skin graft were used to cover the wound. Histological examination 19 months after the transplantation revealed normal structure. Collagenous fibers were orderly arranged. There was no apparent hyperplasia of collagenous fibers. Hair follicles, sweat glands and other skin appendages were not found in the healed area. Grossly, no obvious pigmentation was seen, the surface was smooth with slight wound contraction, and the consistency was flexible. CONCLUSION: Acellular allogenic split-thickness dermis or acellular porcine split-thickness dermis with autologous split-thickness dermis for coverage of deep burn wound and the wound of scar excision is an ideal material.

Adolescent↗
PubMed2006

Novel application method of artificial dermis: one-step grafting procedure of artificial dermis and skin, rat experimental study.

BACKGROUND: Currently, to treat skin defects with artificial dermis (AD), two surgical procedures where the artificial dermis grafting and another secondary skin grafting are required. The purpose of this study was to achieve simultaneous grafting of the artificial dermis and the split-skin. To enhance the wound angiogenesis, cultured endothelial cells, fibroblasts and PDWHF (platelet derived wound healing factor) were employed. METHODS: The experiment consists of following two parts: (1) Investigation to obtain faster angiogenesis into the bilayer artificial dermis: full-thickness wounds created on the back of the rats were treated with the artificial dermis (Terudermis, with silicone sheet, TERUMO Co., Japan). Prior to the artificial dermis grafting, following four groups were established; control group (AD alone, n=6), PDWHF group (AD treated with PDWHF, n=6), cultured cells group (AD treated with cultured endothelial cells and fibroblasts, n=6), combination group (AD treated with PDWHF and cultured cells, n=6). (2) Trial of one-stage grafting of the AD and the skin: simultaneous grafting of the artificial dermis and skin was performed using the same rat model. Before making skin defects, split thickness skin were harvested. Then the skin grafting was carried out immediately after the AD grafting. To allow grafting of the skin onto the artificial dermis, the AD without silicone sheet (Terudermis without silicone sheet, TERUMO Co., Japan) were used. Two groups, control group (AD alone, n=3) and treatment group (AD with PDWF and cultures, n=3) were established. RESULTS: (1) When the artificial dermis were treated with PDWHF, cultured endothelial cells and fibroblasts, vascular invasion into the artificial dermis was observed 5 days after the surgery. (2) In the treatment group, the skin grafted immediately after the artificial dermis grafting was completely taken. CONCLUSIONS: The present study revealed that treatment with PDWHF, combined with cultured endothelial cells and fibroblasts, accelerated wound angiogenesis. By this method, one-step grafting procedure of the artificial dermis and the skin is possible.

Animals↗
PubMed1990

Either chick embryo dermis or retinoid-treated mouse dermis can initiate glandular morphogenesis from mammalian epidermal tissue.

Excess retinoids can cause developing mouse vibrissa follicles to be transformed into mucous glands in organ culture. The objective was to test the hypothesis that retinoids act in this system by altering morphogenetic properties of the dermis. After inititation by retinoic acid (RA) in organ culture, glands were shown to develop further in embryonic skin grafted to the chick chorioallantoic membrane (CAM). Recombinants of 12.5 day mouse epidermis with untreated or RA-treated mouse or chick dermis were then grafted to CAM for 7 days. For homospecific recombinants, 13.5 day mouse dermis originated from 11.5 day skin cultured for 2 days, with or without 5.2 microgram/ml RA. For heterospecific recombinants, 12 day dermis came from chick embryos, previously injected with 250 microgram RA. Glands were absent from the homospecific recombinants including untreated mouse dermis, but appeared in 26% of those with RA-treated dermis. Among heterospecific recombinants, 75% of those with RA-treated chick dermis and 29% of those with untreated dermis had glands. Untreated 10-12 day chick skin contained two forms of endogenous vitamin A, retinol (4.5 microgram/g protein) and dehydroretinol (3.7 microgram/g protein), while 13-14 day mouse skin contained only retinol (1.8 microgram/g protein), as shown by high performance liquid chromatography. RA injection increased retinol and dehydroretinol in chick skin, while RA was undetectable. Thus RA can act through mouse dermis to form epithelial glands and through chick dermis to increase the incidence of glands. The glands in recombinants with untreated chick dermis may result from the higher levels of endogenous retinoids in chick skin, compared with mouse skin.

Allantois↗
PubMed2003

Regenerative surgery for sacral pressure ulcers using collagen matrix substitute dermis (artificial dermis).

Collagen matrix substitute dermis, or artificial dermis, has recently been developed to induce angiogenesis and fibroplasia in deep, poorly vascularized tissue defects, and its use is desirable as a means of achieving effective treatment with less invasion. However, it is difficult to apply collagen matrix to pressure ulcers, because they are usually accompanied by infection with discharge of excessive amounts of exudate or pus and generally exposed to external forces that prevent graft fixation. To overcome these difficulties, the authors demonstrated a novel procedure to exclude unfavorable exudate and external forces. The procedure resulted in successful fixation of the artificial dermis and induction of regeneration in poorly vascularized defects in every case. The histologic findings provided supporting evidence that collagen matrix acts as a scaffold for reconstruction of nearly normal vascular structures coursing perpendicularly in the upper layer of normal dermis.

Humans↗
PubMed1984

A study of the thickness of uninvolved dermis beneath cutaneous malignant melanoma: the ratio of uninvolved dermis to tumour thickness (DT:TT) as a prognostic index.

The histological material from 147 patients treated for clinical stage I primary cutaneous malignant melanoma between 1968 and 1972 was reviewed. All patients had a minimum follow up of 10 years. Measurements were made of the thickness of uninvolved dermis (DT) deep to the tumour and the tumour thickness (TT) itself. The ratio of dermal thickness: tumour thickness (DT:TT) was correlated with clinical progress at follow-up and compared as a prognostic index with tumour thickness alone. The ratio DT:TT was found to be a useful prognostic guide, a value of greater than 2.0 proving to be a very favourable sign. It is suggested that this simple ratio should be routinely reported in all cases of primary cutaneous malignant melanoma to provide an additional index with a view to assessing its value as a prognostic guide.

Female↗
PubMed2005

The use of artificial dermis in the treatment of chronic and acute wounds: regeneration of dermis and wound healing.

Wounds with large loss of deep tissue can be repaired using a dermis substitute. When wounds have an irregular fund, applying a skin graft on these one can be a failure. Integra Dermal Regeneration Template is a bilaminate material, a collagen chondroitin-sponge overlayed with silicone. It heals wounds where conventional methods of repair fail or are too risk. This study analizes Integra's use for chronic and pathological wounds in 7 patients. Applied to wounds reduces inflammation and protects it from a possible contamination or another injury. Imbibition, fibroblast migration, neovascularization, remodeling and maturation are distinct histologic phases of forming neodermis. Trough the silicon layer is possible to observe the histogenesis: the change in color of the matrix is a predictor of its vascularization. When the color has progressed from pink through pale yellow and finally to peach, the neodermis is fully vascolarized. The postoperative care is minimum. Integra is removed after three weeks regenerating a new dermal tissue. So it can be applied a thin skin graft until healing of all patients.

Acute Disease↗
PubMed1986

Different protein synthetic patterns in scale-forming, feather-forming, and apteric embryonic chick dermis.

We have examined the protein synthetic profile of embryonic chick dermis from different regions of both wild-type and scaleless mutant embryos by two-dimensional polyacrylamide gel electrophoresis to determine if differences in inductive capability are associated with different patterns of gene expression. We have found proteins preferentially synthesized in dorsal dermis and anterior tarsometatarsal dermis at stages when these tissues are active in inducing feather or scale histogenesis, respectively, in the epidermis. Apteric dermis, which is unable to induce epidermal derivative formation, synthesizes a subset of the proteins specific to each region. Scaleless mutant dermis, which does not participate in feather or scale formation in vivo, synthesizes all of the dorsal dermis-specific or tarsometatarsal dermis-specific proteins appropriate to its regional origin. However, it lacks one protein common to all types of dermis tested, and synthesizes one protein inappropriate for its location. Examination of the protein synthetic profile of dorsal and anterior tarsometatarsal dermis at early stages of development reveals that young dorsal dermis, which can only form feathers, possesses the protein synthetic pattern specific to that region. Young tarsometatarsal dermis, which has the potential to form either feathers or scales, synthesizes the proteins we have identified as specific to dorsal and older tarsometatarsal dermis. These results suggest that different protein synthetic patterns are associated with different inductive potentials. However, combining young tarsometatarsal dermis with dorsal epidermis, which causes the formation of feathers, does not alter the pattern of proteins synthesized by the dermis. While this result may be due to an artifact of the culture system, an alternative explanation is that the protein synthesis pattern is not related to the type of epidermal derivative induced, but to the pattern in which the derivatives are induced. This is supported by the observation that the feathers formed in recombinants of tarsometatarsal dermis and dorsal epidermis are arranged in a scale pattern.

Animals↗
PubMed1992

Structural and functional evaluation of modifications in the composite skin graft: cryopreserved dermis and cultured keratinocytes.

Structural and functional aspects of modifications in the composite skin graft consisting of cultured keratinocytes and cryopreserved dermis were determined. Cryopreserved human cadaveric dermis separated from skin by short and mild trypsinization was compared with dermis obtained by prolonged incubation in medium and with fresh dermis obtained by the same methods. All types of dermis were shown to retain normal ultrastructure and topographic organization, as detected by scanning and transmission electron microscope and immunofluorescence analysis. However, in fresh skin, the layers were more firmly attached, mechanical separation was more difficult, and residual epidermis often remained attached to the dermis. Keratinocytes attached better, began replication earlier, and generally reached higher cell numbers when cultured on trypsinized dermis than on medium-treated dermis. The performance of several modifications in the reconstitution and grafting procedures of the composite skin graft after transplantation to athymic mice was examined. Cultured epidermis combined onto trypsinized or medium-treated whole and meshed dermis, dermis pregrafted and allowed to take before transplanting epidermis on top, and keratinocytes grown into multiple epithelia on top of trypsinized meshed or whole dermis prior to grafting. The best grafting results were obtained with an "instant" reconstituted skin model: multiple epithelia grown in vitro combined immediately before grafting onto meshed trypsinized dermis. The transplantation results of this modification were significantly better than those of all the other modifications, including initial growth of keratinocytes into multiple epithelia on top of trypsinized dermis prior to grafting.

Animals↗
PubMed2003

[Study on combined implantation of pig dermis and autologous skin in rats].

In this study the treatment effect of combined implantation of autologous skin on pig dermis in injured rats was observed. Twenty-one Wistar rats were used, and the wounds were formed by excising a piece of full thickness skin on the back. After the pig dermis was implanted, the autologous skin was grafted on the dermis at 0.7 and 10 days. In the group with perforated pig dermis, the autograft skin was implanted on the day when the pig dermis was implanted. The healing effect was evaluated by measuring wound area, and by observing the growth of the autograft skin. Two weeks after the autograft skin was implanted, the skin securely adhered to the dermis, and the edge of autograft skin expanded clearly. The wound of the autograft skin implanted in the perforation of the dermis healed completely after 3 weeks, but the other 3 groups had remnant small wound. The autograft skin merged with the dermis and its surrounding tissue, but a clear dividing line still existed between autograft skin and dermis after implantation. The area of the implanted dermis and autograft skin varied from 51.8% to 65.9% compared to its original size. The results suggested that the time and the way of autologous skin grafting on xenogenous dermis may influence wound contraction and healing time.

Animals↗
PubMedDate not supplied

A new system for the cultivation of keratinocytes on acellular human dermis with the use of fibrin glue and 3T3 feeder cells.

The growth of human keratinocytes on human acellular dermis in 4 different culture systems was compared. Epidermis was completely separated and removed from dermis after skin samples had been soaked in 0.1% trypsin at 4 degrees C for 1 week. Forty pieces of saline-washed dermis, 1 cm2 each, were randomized into 4 groups: in group A, human keratinocytes that had undergone 2 to 3 cell passages were seeded (30 x 10(4) cell/cm2) onto the dermis and sprayed with a thin layer of fibrin glue and proliferative 3T3 feeder cells that had been growing separately on the culture dish; in group B, the dermis was only sprayed with fibrin glue; in group C, the dermis was treated with 3T3 cells only; and in group D, the dermis was not sprayed with anything. The dermis samples in all groups were raised on a grid to provide an air-liquid culture system. Histology results of the composite grafts at 2 weeks were assessed as having either scanty colonies of keratinocytes (SCK), continuous stratified epithelium (CSE), or no observable keratinocyte growth. Eight out of the ten dermis samples (80%) in group A demonstrated CSE, and 30% of the samples in group B showed SCK. There were 10% SCK and 20% CSE in group C, and in group D, 30% SCK and 10% CSE were found. The good results in group A indicated that the fibrin glue facilitated the seeding efficiency of the keratinocytes on the dermis and that the vital factors released from the 3T3 feeder cells enhanced the growth and differentiation of the keratinocytes. This model provides an optimal system for the cultivation of keratinocytes on acellular dermis.

3T3 Cells↗
PubMed1991

Avian scale development. XIII. Epidermal germinative cells are committed to appendage-specific differentiation and respond to patterned cues in the dermis.

The ability of the germinative cell population of scutate scale epidermis to continue to generate cells that undergo their appendage-specific differentiation (beta stratum formation), when associated with foreign dermis, was examined. Tissue recombination experiments were carried out which placed anterior metatarsal epidermis (scutate scale forming region) from normal 15-day chick embryos with either the anterior metatarsal dermis from 15-day scaleless (sc/sc) embryos or the dermis from the metatarsal footpad (reticulate scale forming region) of 15-day normal embryos. Neither of these dermal tissues are able to induce beta stratum formation in the simple ectodermal epithelium of the chorion, however, the footpad dermis develops an appendage-specific pattern during morphogenesis of the reticulate scales, while the sc/sc dermis does not. Morphological and immunohistological criteria were used to assess appendage-specific epidermal differentiation in these recombinants. The results show that the germinative cell population of the 15-day scutate scale epidermis is committed to generating suprabasal cells that follow their appendage-specific pathways of histogenesis and terminal differentiation. Of significance is the observation that the expression of this determined state occurred only when the epidermis differentiated in association with the footpad dermis, not when it was associated with the sc/sc dermis. The consistent positioning of the newly generated beta strata to the apical regions of individual reticulate-like appendages demonstrates that the dermal cues necessary for terminal epidermal differentiation are present in a reticulate scale pattern. The observation that beta stratum formation is completely missing in the determined scutate scale epidermis when associated with the sc/sc dermis adds to our understanding of the sc/sc defect. The present data support the conclusion of earlier studies that the anterior metatarsal dermis from 15-day sc/sc embryos lacks the ability to induce beta stratum formation in a foreign epithelium. In addition, these observations evoke the hypothesis that the sc/sc dermis either lacks the cues (generated during scutate and reticulate scale morphogenesis) necessary for terminal differentiation of the determined scutate scale epidermis or inhibits the generation of a beta stratum.

Animals↗
PubMed2004

[Accelerated angiogenesis in artificial dermis with allogenic cultured dermal fibroblasts transplantation].

OBJECTIVE: To evaluate the effects of cryopreserved cultured allogenic dermal fibroblasts on angiogenesis and fibroplasia while artificial dermis grafting by spraying the cells on the graft bed. METHODS: Full thickness skin defect was made on the back of Wistar rat, fibroblasts mixed into fibrin glue (fibroblast group) and same amount fibrin glue (control group) were sprayed separately between the wound bed and artificial dermis in cell density of 1.0 x 10(5) cells/cm2 before the artificial dermis was grafted. On day 5 after grafting, the graft and surrounding tissue were examined histologically for angiogenesis and fibroplasia in the dermis and wound bed with hematoxylin eosin stain, VEGF antibody stain, Masson's trichrome stain and India ink stain. Evans blue perfusion method was also used for detecting the angiogenesis quantitatively. RESULTS: In the fibroblast group, the angiogenesis of graft bed was significantly accelerated on day 5 after grafting; the numbers of the newly formed capillaries were 9.64 +/- 2.36/HP in the fibroblast group and 3.88 +/- 1.62/HP in the control group (P < 0.05). And on day 10 after grafting the angiogenesis was accelerated not only in graft bed but also in the artificial dermis when compared with control group, the newly formed capillaries network was clearly observed in the artificial dermis. Otherwise, the synthesis of collagen was increased in the dermis on day 10 after grafting in the fibroblast group when compared with control group. The immunoreactivity of VEGF antibody in the fibroblast group also showed a stronger expression than that in control group on day 5 after grafting, the numbers of positive cells were 46.04 +/- 8.90/HP in the fibroblast group and 30.08 +/- 7.76/HP in the control group(P < 0.05). CONCLUSION: Transplantation of cryopreserved dermal fibroblasts while artificial dermis grafting can accelerate the angiogenesis and fibroplasia in the artificial dermis and graft bed, thereby accelerate the formation of dermal-like tissue in the artificial dermis.

Animals↗
PubMed2001

Age differences in immunohistochemical localizations of large proteoglycan, PG-M/versican, and small proteoglycan, decorin, in the dermis of rats.

Proteoglycans were localized immunohistochemically in the dermis of Donryu rats, using monoclonal antibodies raised against large proteoglycan (PG-M/versican) and small proteoglycan (decorin). The localizations of these proteoglycans in the dermis were compared between young rats (22-day old) and old ones (24 or 30 months of age), and distinct age differences were observed. In the young dermis, PG-M/versican was observed to be abundant in almost all fibroblastic cells (both cytoplasm and cell processes) whose cellularity was very rich compared with the dermis of old rats. Decorin was only faintly visible in the interstitial fibrous elements of young dermis. In the old dermis, however, decorin was distinctly detected on the fibrous elements, which were diffusely distributed as a fibrous network, and likewise PG-M/versican was visible in only a few fibrous elements which seemed to be the fine processes of fibroblastic cells. In the border layer between epidermis and dermis as well as the basal layer surrounding hair follicles, both large and small proteoglycans could be observed in old dermis. Since decorin, which was abundant in old dermis, has been found to have a growth inhibitory effect, it is conceivable that decorin may be one of the Cell Growth Inhibitory Factors in aging as proposed by Tauchi et al. [17, 18].

Aging↗
PubMed1994

Enzymic and non-enzymic antioxidants in epidermis and dermis of human skin.

We measured enzymic and non-enzymic antioxidants in human epidermis and dermis from six healthy volunteers undergoing surgical procedures. Epidermis was separated from dermis by curettage and antioxidants were measured by high-performance liquid chromatography (HPLC) or standard spectrophotometric methods. The concentration of every antioxidant (referenced to skin wet weight) was higher in the epidermis than in the dermis. Among the enzymic antioxidants, the activities of superoxide dismutase, glutathione peroxidase, and glutathione reductase were higher in the epidermis compared to the dermis by 126, 61 and 215%, respectively. Catalase activity in particular was much higher (720%) in the epidermis. Glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase, which provide reduced nicotinamide adenine dinucleotide phosphate (NADPH), also showed higher activity in the epidermis than the dermis by 111% and 313%, respectively. Among the lipophilic antioxidants, the concentration of alpha-tocopherol was higher in the epidermis than the dermis by 90%. The concentration of ubiquinol 10 was especially higher in the epidermis, by 900%. Among the hydrophilic antioxidants, concentrations of ascorbic acid and uric acid were also higher in the epidermis than in the dermis by 425 and 488%, respectively. Reduced glutathione and total glutathione were higher in the epidermis than in the dermis by 513 and 471%. Thus the antioxidant capacity of the human epidermis is far greater than that of dermis. As the epidermis composes the outermost 10% of the skin and acts as the initial barrier to oxidant assault, it is perhaps not surprising that it has higher levels of antioxidants.

Aged↗
PubMedDate not supplied

Effect of human fibroblast-derived dermis on expansion of tissue from venous leg ulcers.

Novel approaches to healing of chronic wounds, such as venous leg ulcers, include the use of tissue-engineered skin substitutes, e.g., human fibroblast-derived dermis. The exact mechanisms of action of these products and their effects on wound healing at a cellular level are yet to be fully defined. The aim of our study was to evaluate the potential effects of human fibroblast-derived dermis on the healing of chronic wounds using an experimental model. We used a tissue expansion model to examine the effect of human fibroblast-derived dermis on the growth of human tissue biopsied from venous leg ulcers. Further characterization of the cytokine profile produced by human fibroblast-derived dermis in culture was performed using enzyme-linked immunosorbent assay techniques. Addition of medium conditioned with human fibroblast-derived dermis significantly increased the outgrowth of cells from venous leg ulcer biopsies (p = 0.001). We detected bioactive levels of hepatocyte growth factor/scatter factor and interleukin-8 in media conditioned with human fibroblast-derived dermis. Therefore, conditioned media from human fibroblast-derived dermis enhances ex vivo expansion of tissue taken from chronic venous leg ulcers, and contains potent angiogenic factors. These experimental findings may explain the enhanced healing seen with clinical applications of human fibroblast-derived dermis on chronic wounds.

Cell Culture Techniques↗
PubMedDate not supplied

Characterization of collagen orientation in human dermis by two-dimensional second-harmonic-generation polarimetry.

We have proposed an optical probe that can be used to characterize the orientation of collagen fibers in human dermis. A specific probing ability for collagen results from the use of second-harmonic-generation (SHG) light induced by collagen molecules in the tissue. Based on the concept of collagen SHG light, a reflection-type polarization measurement system (named SHG polarimetry) with a probe light spot of 15 microm in diameter has been constructed, and the human reticular dermis has been measured using this system. Resultant data exhibit that the reticular dermis possesses approximately uniaxial orientation of the collagen fibers. Furthermore, we demonstrated a nondestructive measurement of the collagen orientation in the papillary dermis across an epidermis layer. For distribution measurement of the collagen fiber orientation in the reticular dermis, we have extended the SHG polarimetry to one- (1-D) and two-dimensional (2-D) measurement. By the macroscopic 2-D SHG polarimetry, we have observed that the orientation angle and organization degree of collagen fibers vary widely depending on the discrete probing positions in the reticular dermis. Furthermore, microscopic 1-D SHG polarimetry indicated a swell of the orientation angle and a large variance of the organization degree in the collagen fibers in the microscopic region. These results imply that the reticular dermis posses a tangled structure of collagen fibers, which is highly consistent with the result of the anatomical examination of the skin. The proposed method will be a powerful tool for monitoring the microscopic distribution of the collagen fiber orientation in the human dermis.

Achilles Tendon↗
PubMed2002

[Construction of a collagen gel dermis with improved biological property].

OBJECTIVE: To improve the biological property of artificial skin. METHODS: We have ameliorated Hansburgh and Middelkoop's method of manufacturing artificial dermis. The type I collagenase and Dispase were used to isolated neonate prepuce' dermis fibroblast. The gel dermis was constructed by compounding the fibroblast and collagen swelling solution. The property of the collagen gel dermis was measured. RESULTS: The neonate prepuce's dermis fibroblast had property of high proliferation, high activation of the dermis, and it could secrete abundant extracellular matrix (ECM). CONCLUSION: The collagen gel dermis is an useful dermis substitute.

Cell Separation↗