Treatment of vitiligo with 308-nm excimer laser: our experience from a 2-year follow-up of 979 Chinese patients.

BACKGROUND: The 308-nm excimer laser had been proved to be a time-efficient and potent therapeutic alternative for the management of vitiligo. Different results had been reported in different ethnic populations. OBJECTIVE: To investigate the efficacy and related contributing factors of 308-nm excimer laser in Chinese vitiligo patients. METHODS: A total of 979 Chinese patients (3478 lesions) with progressive-stage vitiligo who had received 308-nm excimer laser treatment were recruited from the vitiligo clinic of Shandong Provincial Hospital of Dermatology &Venereology from 2012 to 2014. Efficacy of treatment was evaluated at the end of session by two independent dermatologists based on the before and after images taken. Repigmentation was graded on a 4-point scale: grade 1, poor repigmentation (0-25%); grade 2, moderate repigmentation (26-50%); grade 3, good repigmentation (51-75%); grade 4, excellent repigmentation (76-100%). RESULTS: The mean grade of repigmentation was 2.29, 44.22% showed less than 25% repigmentation, 16.27% showed 26-50% repigmentation, 5.95% showed 51-75% repigmentation and 33.55% showed more than 76% repigmentation. The repigmentation of facial lesions was better than lesions located elsewhere (P < 0.0001), the best response was noted in the periorbital region, while lesions on hands and feet showed poor repigmentation (P < 0.0001). The degree of repigmentation was negatively correlated with disease duration (r = -0.268, P < 0.001), age (r = -0.095, P < 0.001) and shape of lesions (r = -0.114, P < 0.001), whereas it was positively correlated with treatment frequency (r = 0.270, P < 0.001). Lesions with concurrent poliosis were more likely resistant to treatments. CONCLUSION: 308-nm excimer laser appears to be an effective and safe treatment in Chinese vitiligo patients. The clinical response and treatment efficacy was affected by many factors such as age, affected anatomical area, shape of the lesion, disease duration and treatment frequencies.

Studies on p53 and Bax protein expression in Cockayne syndrome cells after UV irradiation and interferon-beta treatment.

Human interferon (HuIFN) has a protective effect against ultraviolet (UV)-induced killing of Cockayne syndrome (CS) and xeroderma pigmentosum (XP) cells. Irradiation with ultraviolet (UV) resulted in nuclear accumulation of p53 in normal human fibroblast cells, and this accumulation was suppressed by treatment with HuIFN-beta. On the other hand, a large amount of p53 was found in both nuclear and cytoplasmic fractions of one SV40-transformed XP and two SV40-transformed CS cell strains irrespective of UV irradiation. Treatment with HuIFN-beta reduced the level of pro-apoptotic Bax protein without suppression of nuclear accumulation of p53 in the CS cells but not in the XP cells. These findings suggest that there are different mechanisms of UV-refractoriness caused by HuIFN-beta in UV-sensitive CS and XP cells.

Mutagenicity of bisphenol A and its suppression by interferon-alpha in human RSa cells.

Bisphenol A is used as a monomer in the production of polycarbonate plastic products. The widespread use of bisphenol A has raised concerns about its effects in humans. Since there is little information on the mutagenic potential of the chemical, the mutagenicity of bisphenol A was tested using human RSa cells, which has been utilized for identification of novel mutagens. In genomic DNA from cells treated with bisphenol A at concentrations ranging from 1x10(-7) to 1x10(-5)M, base substitution mutations at K-ras codon 12 were detected using PCR and differential dot-blot hybridization with mutant probes. Mutations were also detected using the method of peptide nucleic acid (PNA)-mediated PCR clamping. The latter method enabled us to detect the mutation in bisphenol A-treated cells at a dose (1x10(-8)M) equivalent to that typically found in the environment. Induction of ouabain-resistant (Oua(R)) phenotypic mutation was also found in cells treated with 1x10(-7) and 1x10(-5)M of bisphenol A. The induction of K-ras codon 12 mutations and Oua(R) mutations was suppressed by pretreating RSa cells with human interferon (HuIFN)-alpha prior to bisphenol A treatment. The cells treated with bisphenol A at the concentration of 1x10(-6)M elicited unscheduled DNA synthesis (UDS). These findings suggested that bisphenol A has mutagenicity in RSa cells as well as mutagens that have been tested in these cells, and furthermore, that a combination of the PNA-mediated PCR clamping method with the human RSa cell line may be used as an assay system for screening the mutagenic chemicals at very low doses.

Mutation modulating activity in human serum factors induced after parabolic flight.

We have reported that human interferon, one of cytokines present in serum, can confer hypomutability on various human cells. On the contrary, we have also reported that serum factors from cancer patients can enhance cell mutability. Therefore, it seems likely that cell mutability is changed by cytokine-like serum factors in our body. It is one of important space problems whether the mutability of human cells is regulated in response to microgravity and hypergravity (gravitational stress). However, there is little information about cell mutability during such stress. In this study, we investigated whether the mutability is changed by exposing cells to human serum factors after gravitational stress.

Protease activity induced by nicotine in human cells.

Nicotine has a wide range of biological effects, and proteases have been extensively studied for their biological roles in living creatures. The aim of this study is to determine whether nicotine can induce proteolytic protease activity in cultures of various human cell lines. Plasminogen activator-like fibrinolytic protease activity, using 125I-fibrin as substrate in the presence of plasminogen, was estimated in cells with and without nicotine treatment. Among 16 cell lines tested, APr-1 cells were found to have the highest induced protease activity. Partial purification of the proteases was carried out by high performance liquid chromatography gel filtration on TSKG2000SW. Protease inhibitor tests indicated that the proteases induced by nicotine are serine proteases.

Suppression of okadaic acid-induced apoptosis by overexpression of calpastatin in human UV(r)-1 cells.

Proteolytic systems have various involvements in apoptotic pathways. To understand the role of calpain in apoptosis, calpastatin, a specific inhibitor of calpain, was overexpressed in human UV(r)-1 fibroblasts by transfection of its cDNA. The elevated expression of calpastatin resulted in decreased survival in the presence of okadaic acid (OA) but in no apparent alteration in the sensitivity toward other drugs such as 5-fluorouracil, mitomycin C and methotrexate. After treatment with OA, a typical apoptotic DNA ladder was observed in control vector-transfected cells but not in calpastatin-transfected cells. This indicates that OA-induced apoptosis was suppressed by overexpression of calpastatin. Further immunoblot analysis showed that the OA-induced hyperphosphorylation of c-Jun was inhibited in calpastatin-transfected cells. This might be involved in the resistance to OA-induced cell death in calpastatin-overproducing cells.