We have developed a method to fabricate cultured epithelium for skin repair using mucosal cells. We grafted this epithelium in six cases. The site where the mucosal epithelium was transplanted ...keratinized normally within 4 weeks and formed normal skin. Mucosal epithelial cells have many advantages over skin epidermal keratinocytes: (1) Mucosal epithelial cells grow faster than skin keratinocytes. (2) Cultured epithelial sheets formed using mucosal cells remain viable for at least 14 days in vitro. (3) The oral cavity is a suitable location to take a tissue segment because scar due to biopsy is inconspicuous. Therefore, mucosal epithelial cells are a potential new source of cells for cultured epithelial graft.
Cultured epithelium has proven to be a good grafting material for skin defects. In our experience two kinds of epithelial cells, skin keratinocytes and mucosal cells, have been used to fabricate ...cultured epithelial sheets and autografted to the patients. Traumatic scars of the face were treated by cultured epidermal epithelium (CEE). The skin graft in the oral cavity was replaced by mucosa using cultured mucosal epithelium (CME). Also, the CME was applied to the skin defects at the donor sites of split-thickness skin grafts. Postsurgical follow-up showed good results. As a result, CME was useful in improving the biological environment around the abutments of dental implants, and it also promoted the re-epithelialization of skin defects. From our investigations, CEE/CME are promising treatment modalities which can reduce pain and speed up the healing process in burn patients. Therefore, cultured epithelium banks are worth establishing for auto- and allografting of skin/mucosal defects.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Many clinical studies have demonstrated the usefwness of cultured epithelial grafts. Recently, cultured epithelium has been preserved by freezing and successfuly grafted after thawing. However, few ...papers have described morphological changes that occur after freezing cultured epithelium. We studied the morphological changes of cultured mucosal epithelial sheets and cultured epidermal sheets after freezing. In our freezing procedure, glycerin and dimethyl sulfoxide (DMSO) were used as cryoprotectants. Each epithelial sheet was stored for 3 weeks at -80°C or -196°C. The structures of both types of epithelial sheets were generally maintained after freezing storage. However, cultured mucosal epithelium showed mild showing vacuolation around the nuclei after freezing with DMSO. The results indicated that cultured mucosal epithelial sheets can be stored by freezing and that their structure can be maintained by using glycerin.
In this study, cultured epithelium was formed using serially cultivated human oral mucosal cells and transplanted onto nude mice. The morphological changes of the epithelium were observed after ...transplantation. The grafting procedures of the cultured epithelium was a modification of Barrandon's method. With this procedure, the cultured epithelium was transplanted without external trauma or infection. The cultured epithelium took within 1 week and gradually increased its epithelial thickness. Until 4 weeks after grafting, the grafted epithelium formed normal mucosal epithelium composed of 7-10 epithelial cell layers. However, no keratinization of the epithelium was observed. On the other hand, dermislike connective tissue was observed beneath the grafted epithelium. These results suggest that the cultured mucosal epithelium can be successfully transplanted and form a normal mucosal epithelial layer.
Cultured stratified epithelium for grafting was prepared using human keratinocytes. In the field of plastic surgery, many patients who received grafts of cultured epithelium have been reported. ...However, no case in the maxillofacial region has been reported. Here we report 2 cases of traumatic scars in the maxillofacial region that were treated by cultured epithelium. The patients were a 21-year-old man and a 9-year-old boy who complained of deformity due to a traumatic scar. In both cases, small skin segments, 1-2cm2, were obtained before operation, and epithelial cells were cultured by the methods of Green et al, using 3T3 cells as the feeder layer. After 3 weeks, 175-350cm2 cultured epithelium was prepared. Then, surgical debridment of the scar was carried out, and cultured epithelium was grafted onto the epithelial defects. Cultured epithelium was completely taken within 1 week. Subsequently, that the surface of the graft became smooth and pigmentation faded away.
Numerous clinical reports have shown the utility of cultured epithelial grafting in the field of plastic and reconstructive surgery. Recently, freezing storage of the cultured epithelium has been ...tried and has successfully grafted after thawing. It is clinically convenient if it is possible for cultured epithelium to keep its normal structure and viability. However, few papers have described the structural changes in cultured epithelium after freezing storage. In the present study, the morphological changes and cell viability of cultured mucosal epithelial sheets after freezing were studied in comparison with cultured epidermal sheets. Furthermore, we discuss the effect of storage temperature and cryoprotectants.
As a result, there were some structural changes such as vacuolar degeneration in the cultured mucosal sheets using dimethyl sulphoxide (DMSO) as a cryoprotectant. Such changes were more clearly observed at −80°C than at −196°C with DMSO. However, little morphological change was observed in both epithelial sheets cultured with glycerin. The cell viability analysed by flow cytometry showed that more than 62% of the cells kept their viability after freezing storage. These results suggest that the optimum conditions of freezing for cultured epithelium were −196°C storage by slow cooling methods with glycerin as a cryoprotectant.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Osseointegrated implants are useful in improving the masticatory function in patients who undergo mandibular reconstruction after tumor resection. However, many of these patients have thick, mobile ...soft tissue, which causes inflammation around the abutments. Although mucosal or skin grafts have been used to manage soft tissue problems that occur around the abutments, each have disadvantages: the donor site size is limited in mucosal grafts, and hair growth and keratinization cause discomfort with skin grafts. This paper describes a new method for soft tissue management using cultured mucosal grafs which overcome these disadvantages.
Abstract
The use of carbon nanotubes in the industry has grown; however, little is known about their toxicological mechanism of action. Single-wall carbon nanotube (SWCNT) suspensions were ...administered by single intratracheal instillation in rats. Persistence of alveolar macrophage-containing granuloma was observed around the sites of SWCNT aggregation at 90 days post-instillation in 0.2-mg- or 0.4-mg-injected doses per rat. Meanwhile, gene expression profiling revealed that a large number of genes involved in the inflammatory response were markedly upregulated until 90 days or 180 days post-instillation. Subsequently, gene expression patterns were dramatically altered at 365 days post-instillation, and the number of upregulated genes involved in the inflammatory response was reduced. These results suggested that alveolar macrophage-containing granuloma reflected a characteristic of the histopathological transition period from the acute-phase to the subchronic-phase of inflammation, as well as pulmonary acute phase response persistence up to 90 or 180 days after intratracheal instillation in this experimental setting. The expression levels of the genes Ctsk, Gcgr, Gpnmb, Lilrb4, Marco, Mreg, Mt3, Padi1, Slc26a4, Spp1, Tnfsf4 and Trem2 were persistently upregulated in a dose-dependent manner until 365 days post-instillation. In addition, the expression levels of Atp6v0d2, Lpo, Mmp7, Mmp12 and Rnase9 were significantly upregulated until 754 days post-instillation. We propose that these persistently upregulated genes in the chronic-phase response following the acute-phase response act as potential biomarkers in lung tissue after SWCNT instillation. This study provides further insight into the time-dependent changes in genomic expression associated with the pulmonary toxicity of SWCNTs.
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IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Epigenetic alteration is an emerging paradigm underlying the long-term effects of chemicals on gene functions. Various chemicals, including organophosphate insecticides and heavy metals, have been ...detected in the human fetal environment. Epigenetics by DNA methylation and histone modifications, through dynamic chromatin remodeling, is a mechanism for genome stability and gene functions. To investigate whether such environmental chemicals may cause epigenetic alterations, we studied the effects of selected chemicals on morphological changes in heterochromatin and DNA methylation status in mouse ES cells (ESCs). Twenty-five chemicals, including organophosphate insecticides, heavy metals and their metabolites, were assessed for their effect on the epigenetic status of mouse ESCs by monitoring heterochromatin stained with 4¢,6-diamino-2-phenylindole (DAPI). The cells were surveyed after 48 or 96 h of exposure to the chemicals at the serum concentrations of cord blood. The candidates for epigenetic mutagens were examined for the effect on DNA methylation at genic regions. Of the 25 chemicals, five chemicals (diethyl phosphate (DEP), mercury (Hg), cotinine, selenium (Se) and octachlorodipropyl ether (S-421)) caused alterations in nuclear staining, suggesting that they affected heterochromatin conditions. Hg and Se caused aberrant DNA methylation at gene loci. Furthermore, DEP at 0.1 ppb caused irreversible heterochromatin changes in ESCs, and DEP-, Hg- and S-421-exposed cells also exhibited impaired formation of the embryoid body (EB), which is an in vitro model for early embryos. We established a system for assessment of epigenetic mutagens. We identified environmental chemicals that could have effects on the human fetus epigenetic status.
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