These findings suggest that increased secretion of HGF and SCF by dermal fibroblasts may be associated with the accentuated epidermal melanization observed in CALMs in the skin of NF1 patients.
The diameter of very small vessels (about 0.5 mm or less) causes difficulties in placing forceps into the lumen and in completing anastomosis without inadvertently catching the back wall during supermicrosurgery. The insertion of nylon monofilaments into small vessels has overcome this problem. We implanted superficial inferior epigastric arterial (SIEA) flaps in 10 rats and also performed supermicroanastomosis (diameter, 0.15 mm) using SIEA flaps in mice. The back wall was never inadvertently caught using the intravascular stenting (IVaS) method, and the immediate patency rate was 100%. An advantage of using nylon for IVaS is that various sizes can be selected. We successfully anastomosed vessels with a minimum diameter of 0.15 mm. Even smaller vessels can be precisely and safely anastomosed using the IVaS method.
QSR laser combined with the topical bleaching pretreatment appeared to treat ADM consistently with a low occurrence rate of PIH and lessen the number of laser sessions and total treatment period and may also be applied to any other lesions with both epidermal and dermal pigmentation.
Keloids are skin abnormalities that are characterized by excessive deposition of collagen bundles in the dermis. Patients with keloids complain not only about their cosmetic appearance, but also about continuous itching and/or tenderness associated with chronic inflammation. Degradation of extracellular matrix (ECM) may be upregulated, associated with the expansion of keloids into circumferential skin, and high metabolic activity of keloid tissues may be due to increased matrix metalloproteinase (MMP) activity. Based on these hypotheses, we examined differences in expression of MMP-1, MMP-8, and MMP-13 between keloid-derived and normal dermal fibroblasts. Since retinoids are potent inhibitors of MMPs in the treatment of photoaged skin and cancers, we also examined whether or not tretinoin affects MMP expression of keloid-derived fibroblasts. The results of real-time polymerase chain reaction and ELISA demonstrated significant upregulation of MMP-13 and significant downregulation of MMP-1 and MMP-8 in keloid-derived fibroblasts, at both mRNA and protein levels. MMP-1 mRNA expression in the control group was significantly upregulated after the addition of tretinoin, whereas no significant change was observed in the keloid group. MMP-8 mRNA expression in the control group was significantly upregulated by tretinoin, with the peak at 12 h, while no significant change was observed in the keloid-derived fibroblasts. In contrast, the remarkably elevated MMP-13 mRNA expression in the keloid group was significantly suppressed, with the peak suppression at 12 h after addition of tretinoin, while MMP-13 mRNA expression in the control group was not significantly changed. The decrease in MMP-1 and MMP-8 may contribute to accumulation of type I and type III collagen in keloid tissues, and this mechanism may be modulated by molecular interaction with MMP-13. Tretinoin appeared to reverse the abnormal expression profile of MMPs in keloid-derived fibroblasts, such as markedly elevated expression of MMP-13, partly through inactivation of AP-1 pathway. The present results suggest that tretinoin may be clinically useful to improve the chronic inflammation seen in keloids and prevent expansion of keloid tissues into circumferential normal skin.
These findings suggest that IL-1alpha secretion increases as cells grow older, and the increased secretion of IL-1alpha by aged keratinocytes may stimulate HGF production in dermal fibroblasts paracrinely and ET-1 production in keratinocytes autocrinely, which stimulates melanocyte proliferation and induces an increase of tyrosinase activity in melanocytes. Because IL-1alpha is a primary mediator that responds to inflammation and injury, the transcription of genes involved in skin inflammation may be persistently induced in the aged skin. Thus the increased secretion of IL-1alpha by aged keratinocytes in the aged skin may play a role in the accentuated cutaneous pigmentation and other skin ageing.
Because wound exudate includes secreted proteins that affect wound healing, its biochemical analysis is useful for objective assessment of chronic wounds. Wound blotting allows for collection of fresh exudate by attaching a nitrocellulose membrane onto the wound surface. To determine its applicability for several analysis methods and its executability in clinical wound assessment, this study comprised an animal experiment and clinical case reports. In the animal experiment, full-thickness wounds were created on the dorsal skin of mice, and exudate samples were collected daily by a conventional method and by wound blotting. Extremely small but adequate volumes of exudate were collected by wound blotting for subsequent analysis in the animal experiments. Immunostaining showed the concentration and distribution of tumor necrosis factor (TNF) α. The activity of alkaline phosphatase was visualized by reaction with chemiluminescent substrate. The TNF distribution analysis indicated three different patterns: wound edge distribution, wound bed distribution, and a mostly negative pattern in both the animal and clinical studies, suggesting association between the TNF distribution pattern and wound healing. Our results indicate that wound blotting is a convenient method for biochemical analysis of exudate and a candidate tool with which to predict the healing/deterioration of chronic ulcers.
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