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101.
Although lupus erythematosus is known to be more common among women of color, the study populations in previous reports were predominantly Caucasian and there is scarce information on Asian patients. Therefore, we performed a retrospective study using a nationwide population-based cohort in South Korea. The average annual incidence of cutaneous lupus was 4.36/100 000. Among 634 patients with cutaneous lupus, 20.8% had systemic disease: cutaneous lupus was diagnosed before systemic lupus in 4.26% and after systemic lupus in 8.52%. More female patients than male patients developed systemic lupus erythematosus. The average time to progression to systemic lupus was 1.53 ± 1.46 years.  相似文献   
102.
Solitary fibrous tumor (SFT) is a relatively uncommon mesenchymal neoplasm that usually arises in the pleura, but also has been reported in numerous extrapleural locations, including cutaneous site. The skin lesion presents as a circumscribed nodule or tumor, mainly on the head and neck. A 41-year-old male presented with 6 months history of nail lesion without symptom on the left third finger. The lesion is slightly yellowish discoloration with subungual erythematous nodule and distal onycholysis. Biopsy specimen from the nail lesion showed the spindle cells form patternless pattern with hypercellular and hypocellular area. And small blood vessels and dilated vascular spaces were present. The result of special stain for specimen showed that positive for CD34, Bcl-2, and CD99 but negative for S-100, FactorXIIIa, and smooth muscle action. Recognition of this uncommon location of SFT is important because of possible confusion with other subungual tumors, including glomus tumor, fibroma and other fibrohistiocytic tumors like dermatofibrosarcoma protuberans, superficial acral fibromyxoma and cellular digital fibroma. Here in, we report a case of SFT of subungual region. We think this case is interesting because of uncommon location and may be helpful to more understand the character of this disease.  相似文献   
103.
104.
A 62-year-old female, with previous history of asthma and hypertension, presented with generalized hyperpigmented skin lesion, found a year ago. Physical examination revealed brown colored lichenified and sclerotic patches on the lower abdomen and flexural areas of extremities. Punch biopsy was performed and histopathological examination revealed hyperkeratosis, follicular plugging and thinning in epidermis. In dermoepidermal junction, cleft like space separating atrophic epidermis and dermis was seen. Also, lichenoid lymphocytic infiltration was observed in mid-dermis. Based on clinical and histopathological findings, a diagnosis of generlaized lichen sclerosus et atrophicus (LSA) was made. Other laboratory examinations were unremarkable. As there is no standard treatment for LSA, the patient received various treatments including topical steroid, tacrolimus and narrow-band ultraviolet B therapy. The skin lesion has softened and its color improved after treatment. LSA is defined as infrequent chronic inflammatory dermatosis with anogenital and extragenital manifestations. Generalized type is rare and genital involvement is the most frequent and often the only site of involvement. We report this case as it is an uncommon type of LSA with generalized hyperpigmented and sclerotic skin lesion in a postmenopausal female patient.  相似文献   
105.
106.
Background: Rosacea is characterized by erythema on face, especially erythema and linear telangiectasia on the nose. Currently, various vascular lasers are used for treatment, and among them, are long-pulsed Nd:YAG(LPNY) and pulsed dye laser (PDL). Objectives: This study compared the efficacy of LPNY and PDL in treating rosacea-associated nasal telangiectasia. Methods: Patients with rosacea who showed erythema and telangiectasia on the nose were included. Each patient was treated with PDL on the left side of the nasal bridge, and LPNY on the right side, three times with 4-week intervals. At the end of the treatment, two independent dermatologists evaluated overall treatment response compared with baseline. Results: The physician’s assessment of treatment concluded that good improvement was seen in six PDL and seven LPNY patients, and excellent improvement five PDL and four LPNY patients. There was no significant difference (= 0.62, 95%CI) between the groups. Overall improvement was similar; however, LPNY induced a greater response in thick, dilated vessels, while erythema with mild telangiectasia was more responsive to PDL. Conclusion: Both LPNY and PDL are effective in treating rosacea-associated nasal telangiectasia. If LPNY is used properly to avoid side effects with careful consideration, it can also be used as a good modality.  相似文献   
107.
PURPOSE: The loss of corneal endothelial cells associated with aging and possibly other causes has been speculated to be related to exposure to reactive oxygen species (ROS). The current study was conducted to investigate, by use of photosensitizers, the underlying mechanisms involved in the death of bovine corneal endothelial cells (BCENs) caused by ROS. METHODS: BCEN cells in primary culture were treated with a photosensitizer (riboflavin or rose bengal) with light exposure. The patterns of cell damage and death were assessed using an acridine orange-ethidium bromide differential staining method, TdT-mediated dUTP nick-end labeling (TUNEL) assay, and transmission electron microscopy. The cytotoxicity was assayed by mitochondrial function using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) testing. Antioxidants, including catalase, L-histidine, salicylic acid, and superoxide dismutase, were used to determine the types of ROS involved. Activation of nuclear factor (NF)-kappaB was examined by fluorescent immunocytochemistry with anti-p65 antibody. RESULTS: Light-irradiated riboflavin or rose bengal resulted in a significant decrease in viability of BCEN cells. Chromosomal condensation and fragmentation were observed in apoptotic cells, and membrane lysis and damage of cell ultrastructures were observed in necrotic cells. Riboflavin induced apoptosis at 30 minutes and thereafter and induced necrosis after 2 hours. Rose bengal was shown to cause similar effects within half the time required for the effects of riboflavin. Catalase and salicylic acid were found to provide protection for BCENs from cytotoxic effects of riboflavin, and L-histidine was found to protect BCENs from cytotoxicity induced by rose bengal. Kinetic studies using immunocytochemistry showed that NF-kappaB was translocated into the nucleus within 15 minutes and 30 minutes after treatment with rose bengal and riboflavin, respectively. CONCLUSIONS: The cytotoxic effects of photo-irradiated riboflavin and rose bengal are shown to be mediated by two distinct but parallel pathways, one leading to apoptosis and the other to necrosis. Possible involvement of NF-kappaB in cell death is suggested. These findings provide potential leads for future investigation into the molecular mechanisms of loss of corneal endothelial cells related to aging, oxidative stress, and possibly other similar causes.  相似文献   
108.

Aims of the study

We recently reported the potential antioxidant and anti-inflammatory activities of umbelliferone 6-carboxylic acid (UMC) isolated from the whole plants of Angelica decursiva. In this study, we elucidated the anti-inflammatory mechanisms of UMC in vitro and in vivo.

Methods

The inhibitory effects of UMC on the production of nitric oxide (NO), prostaglandin E2 (PGE2), and tumor necrosis factor-α (TNF-α), the expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the activation of nuclear factor kappa B (NF-κB) were evaluated using lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The reactive oxygen species (ROS) generation inhibitory activity of UMC was evaluated using t-butyl hydroperoxide (t-BHP)-induced RAW 264.7 cells. Furthermore, the in vivo anti-inflammatory activity of UMC was evaluated using carrageenan induced mouse paw edema model.

Results

UMC dose-dependently inhibited NO and PGE2 production by down-regulating iNOS and COX-2 protein expression in LPS-stimulated RAW 264.7 macrophages. UMC also suppressed the production of the proinflammatory cytokine TNF-α in LPS stimulated RAW 264.7 cells in a concentration dependent manner. In addition, UMC dose-dependently prevented LPS-induced nuclear translocation of NF-κB in RAW 264.7 macrophages. Furthermore, UMC exhibited the inhibitory activity against t-BHP-induced ROS generation in RAW 264.7 cells with an IC50 value of 705.1 μg/ml. Moreover, UMC inhibited λ-carrageenan induced mouse paw edema by 70.40 and 60.20% at doses of 50 and 25 mg/kg body weight, respectively.

Conclusion

The combined results of this study indicate that UMC is an important anti-inflammatory constituent of A. decursiva and its anti-inflammatory effect was due to its ability to inhibit the production of inflammatory mediators via inhibition of NF-κB activation pathway.  相似文献   
109.
Oh JY  Kim MK  Shin KS  Shin MS  Wee WR  Lee JH  Ko SM  Lee JL 《Cornea》2007,26(7):840-846
PURPOSE: To examine the effects of cryopreservation on the viability of cultivated corneal limbal and conjunctival epithelial cells and to evaluate the optimal conditions for cryopreservation. METHODS: The cultivated human limbal epithelial cells (HLECs) were stored in media including 20%, 50%, and 90% fetal bovine serum (FBS) and 10% dimethyl sulfoxide (DMSO) at -196 degrees C for 1 week. The cultivated rabbit conjunctival epithelial cells were stored in 10%, 20%, and 50% FBS with 10% glycerol or DMSO as a cryoprotectant at -196 degrees C for 1 week. After thawing, cell viability was assessed using the trypan blue vital staining and 3-[4,5-dimethylthiazol-2-yl]-2,5-dephenyl tetrazolium bromide (MTT) assay. Immunofluorescent staining was performed with cytokeratin 3/12 antibody. Colony-forming efficiency (CFE) was evaluated 2 weeks after culture. RESULTS: HLECs cryopreserved with 50% FBS showed the highest cell viability, whereas those with 20% FBS revealed the lowest survival rate (87.1% +/- 0.8% and 79.8% +/- 4.01%, respectively; P = 0.030). CFE of HLECs was 2.13 +/- 1.35%, 2.31 +/- 2.23%, and 1.94 +/- 0.72% in cells with 20%, 50%, and 90% FBS, respectively (P > 0.05). For conjunctival epithelial cells, the cell viability was the highest with 50% FBS and 10% glycerol (95.0% +/- 4.27%), and the lowest survival rate was observed in the condition of 10% FBS and 10% DMSO (80.0% +/- 5.49%). CFE of cryopreserved conjunctival epithelial cells was 14.1% +/- 1.9% in cells with 20% FBS and glycerol and 13.5% +/- 2.0% in those with 20% FBS and DMSO (P > 0.05). HLECs expressed CK3/12 after cryopreservation in all conditions examined. CONCLUSIONS: The best results were yielded by 50% FBS for cell viability in HLECs. Glycerol seems to be superior to DMSO in cell viability of the rabbit conjunctival epithelium after cryopreservation.  相似文献   
110.
Protective effect of uridine on cornea in a rabbit dry eye model   总被引:1,自引:0,他引:1  
PURPOSE: To investigate the effect of uridine on cultured human corneal epithelial cells and keratocytes in vitro and to evaluate whether the application of uridine-containing eye drops could improve ocular surface health in an in vivo dry eye model. METHODS: Uridine was added to cultured epithelial cells (3 x 10(4) cells/well) and keratocytes (1 x 10(4) cells/well) at various concentrations (0.5-50 microM). Cytotoxicity was tested with the use of MTT assay, and the cells were assessed for apoptosis with the use of flow cytometry. Expressions of hyaluronic acid (HA), glycosaminoglycan (GAG), nitric oxide (NO), and matrix metalloproteinase (MMP)-9 were measured. In vivo, the degree of reepithelialization was assessed after topical application of uridine (100 microM) in a rabbit corneal wound model. Changes in tear production and conjunctival goblet cell counts were investigated after instillation of various concentrations of uridine-containing eye drops in a rabbit dry eye model. RESULTS: In vitro, uridine showed no cellular toxicity. It increased the biosynthesis of HA and GAG and reduced MMP-9 levels in cultured corneal epithelial cells and keratocytes. In vivo, uridine enhanced corneal wound healing and significantly increased the number of conjunctival goblet cells in rabbits. CONCLUSIONS: Uridine can restore the health of the ocular surface in a rabbit corneal wound and dry eye model.  相似文献   
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