ABSTRACT
INTRODUCTION: Non-melanoma skin cancers (NMSCs) are the most common cancers in the world, but the risk of internal malignancy in patients with NMSC has not been well investigated. OBJECTIVES: We aimed to assess the risk of internal malignancy in patients with NMSC compared with controls without NMSC in Korean population. METHODS: This nationwide cohort study, compared 27 259 NMSC patients with 54 518 matched controls without NMSC, 40 years or older using the data from Korea Health Insurance Review and Assessment Service from 2007 to 2016. The first 2 years were washout period, and we followed the patients for 8 years to observe the development of any internal malignancies after a diagnosis of NMSC. The Cox proportional hazard model was used to determine the hazard ratios (HRs) for developing internal malignancies. RESULTS: The overall risk of internal malignancies at all sites was 2727.7 and 1392.4 per 100 000 person-years for the patients with NMSC and controls, respectively. The risk was significantly higher in the patients with NMSC (HR 1.866, 95% confidence interval [CI] 1.768-1.970). Bone cancer showed the highest risk (HR 12.745, 95% CI 6.288-25.834), followed by nasal cavity and larynx (HR 10.279, 95% CI 6.178-7.103), oral cavity and pharynx (HR 10.211, 95% CI 7.375-14.137), anus and anal canal (HR 8.147, 95% CI 3.893-17.051) and cervical (HR 5.900, 95% CI 3.694-9.423) cancers with risks greater than fivefold higher in NMSC patients compared with the controls. The risks of cancers of the thorax, oesophagus, breast, lung, stomach, thyroid gland and non-Hodgkin's lymphoma were also statistically higher in the patients with NMSC. In contrast, the risks of cancers of the colon and rectum were found to be significantly decreased in the patients with NMSC (HR 0.765, 95% CI 0.657-0.890). CONCLUSION: Patients with NMSC require careful screening and follow-up for internal malignancy.
Subject(s)
Neoplasms, Second Primary/pathology , Skin Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Humans , Male , Middle Aged , Neoplasms, Second Primary/epidemiology , Population Surveillance , Republic of Korea/epidemiology , Risk Factors , Skin Neoplasms/epidemiologyABSTRACT
We report a fuel-dependent reactor electron antineutrino (ν[over ¯]_{e}) yield using six 2.8 GW_{th} reactors in the Hanbit nuclear power plant complex, Yonggwang, Korea. The analysis uses 850 666 ν[over ¯]_{e} candidate events with a background fraction of 2.0% acquired through inverse beta decay (IBD) interactions in the near detector for 1807.9 live days from August 2011 to February 2018. Based on multiple fuel cycles, we observe a fuel ^{235}U dependent variation of measured IBD yields with a slope of (1.51±0.23)×10^{-43} cm^{2}/fission and measure a total average IBD yield of (5.84±0.13)×10^{-43} cm^{2}/fission. The hypothesis of no fuel-dependent IBD yield is ruled out at 6.6σ. The observed IBD yield variation over ^{235}U isotope fraction does not show significant deviation from the Huber-Mueller (HM) prediction at 1.3 σ. The measured fuel-dependent variation determines IBD yields of (6.15±0.19)×10^{-43} and (4.18±0.26)×10^{-43} cm^{2}/fission for two dominant fuel isotopes ^{235}U and ^{239}Pu, respectively. The measured IBD yield per ^{235}U fission shows the largest deficit relative to the HM prediction. Reevaluation of the ^{235}U IBD yield per fission may mostly solve the reactor antineutrino anomaly (RAA) while ^{239}Pu is not completely ruled out as a possible contributor to the anomaly. We also report a 2.9 σ correlation between the fractional change of the 5 MeV excess and the reactor fuel isotope fraction of ^{235}U.
ABSTRACT
BACKGROUND: Car drivers are generally exposed to direct sunlight during commuting hours, which may lead to irreversible skin damage; however, topographical analysis for different facial areas has not been reported. METHODS: Facial areas were divided topographically into 11 areas based on esthetic units. We performed a preliminary study to identify the delivery pattern of solar energy on the face in the car during commuting time; subsequently, 15 drivers aged above 50 years were enrolled. Statistical evaluation was performed to investigate topographical differences between the left and right sides of the face and between sexes. RESULTS: The left side of the face was different from the right side for L*, a*, and b* on the infraorbital area and L* and b* on the temporal area. Differences were found for L*, a*, or b* between sexes on the central and right face, but not on the left. The left side had more severe hyperpigmentation and wrinkles than the right on average. CONCLUSION: The left facial area, especially the infraorbital and temporal areas, of Korean automobile commuters was vulnerable to sun damage. Therefore, automobile drivers should care about these areas while driving to prevent long-term effect from chronic solar damage.
Subject(s)
Face/radiation effects , Skin/radiation effects , Sunlight/adverse effects , Automobiles , Face/pathology , Female , Humans , Hyperpigmentation/pathology , Male , Middle Aged , Republic of Korea/epidemiology , Skin/pathology , Skin Aging/pathology , TransportationABSTRACT
The RENO experiment reports more precisely measured values of θ_{13} and |Δm_{ee}^{2}| using â¼2200 live days of data. The amplitude and frequency of reactor electron antineutrino (ν[over ¯]_{e}) oscillation are measured by comparing the prompt signal spectra obtained from two identical near and far detectors. In the period between August 2011 and February 2018, the far (near) detector observed 103 212 (850 666) ν[over ¯]_{e} candidate events with a background fraction of 4.8% (2.0%). A clear energy and baseline dependent disappearance of reactor ν[over ¯]_{e} is observed in the deficit of the measured number of ν[over ¯]_{e}. Based on the measured far-to-near ratio of prompt spectra, we obtain sin^{2}2θ_{13}=0.0896±0.0048(stat)±0.0047(syst) and |Δm_{ee}^{2}|=[2.68±0.12(stat)±0.07(syst)]×10^{-3} eV^{2}.
ABSTRACT
The RENO experiment has analyzed about 500 live days of data to observe an energy dependent disappearance of reactor ν[over ¯]_{e} by comparing their prompt signal spectra measured in two identical near and far detectors. In the period between August of 2011 and January of 2013, the far (near) detector observed 31 541 (290 775) electron antineutrino candidate events with a background fraction of 4.9% (2.8%). The measured prompt spectra show an excess of reactor ν[over ¯]_{e} around 5 MeV relative to the prediction from a most commonly used model. A clear energy and baseline dependent disappearance of reactor ν[over ¯]_{e} is observed in the deficit of the observed number of ν[over ¯]_{e}. Based on the measured far-to-near ratio of prompt spectra, we obtain sin^{2}2θ_{13}=0.082±0.009(stat)±0.006(syst) and |Δm_{ee}^{2}|=[2.62_{-0.23}^{+0.21}(stat)_{-0.13}^{+0.12}(syst)]×10^{-3} eV^{2}.
ABSTRACT
Muscular dystrophy (MD) is a genetically and clinically heterogeneous group of disorders. Here, we performed targeted sequencing of 18 limb-girdle MD (LGMD)-related genes in 35 patients who were highly suspected of having MD. We identified one or more pathogenic variants in 23 of 35 patients (65.7%), and a genetic diagnosis was performed in 20 patients (57.1%). LGMD2B was the most common LGMD type, followed by LGMD1B, LGMD2A, and LGMD2G. Among the three major LGMD types in this group, LGMD1B was correlated with the lowest creatine kinase (CK) levels and the earliest onset, whereas LGMD2B was correlated with the highest CK levels and the latest onset. Thus, next-generation sequencing-based gene panels can be a helpful tool for the diagnosis of MDs, particularly in young children and those displaying atypical symptoms.
ABSTRACT
Arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome is an autosomal recessive disorder caused by mutations in the VPS33B and VIPAS39. Here, we report novel mutations identified in four patients with ARC syndrome. We analyzed the entire coding regions of the VPS33B and VIPAS39 genes by direct sequencing. To detect novel splice site mutations, mRNA transcripts were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. All four patients had compound heterozygous variants in the VPS33B gene. One patient had a previously reported splice site variant with unknown significance, c.239+5G>A, and a novel nonsense mutation, c.621G>A. The other three patients had the c.403+2T>A mutation, and each of them carried one of the splice site variants, c.239+5G>A or c.499-11G>A. c.239+5G>A and c.499-11G>A created novel splice sites which resulted in abnormal transcripts. No significant VIPAS39 mutation was detected in all patients. In patients suspected with ARC syndrome, mutation analysis of the VPS33B gene should be employed as a primary diagnostic test before performing invasive testing procedures such as organ biopsies. Performing mRNA analysis can be useful in predicting the pathogenic phenotype when the mutation seems to affect a normal splicing mechanism.
Subject(s)
Arthrogryposis/genetics , Cholestasis/genetics , Mutation , RNA Splice Sites/genetics , Renal Insufficiency/genetics , Vesicular Transport Proteins/genetics , Arthrogryposis/diagnosis , Cholestasis/diagnosis , DNA Mutational Analysis , Female , Heterozygote , Humans , Infant , Infant, Newborn , Male , Phenotype , Renal Insufficiency/diagnosis , Republic of KoreaABSTRACT
BACKGROUND: The quantitative difference of the light reflected from a skin surface can be analyzed using parallel-polarized light (PPL) photography when combined with an analytic technique similar to colorimetric photography. OBJECTIVE: To improve the PPL photography technique as an assessment tool for the evaluation of skin condition using light-emitting diodes (LED) of different colors. METHOD: Parallel-polarized light images were taken using white and green LED illuminators. The acquired images were transformed to CIELAB coordinates. An in-house skin conductance meter was constructed to assess skin hydration level. A dermatologist evaluated the clinical grading of dryness and glossiness. These clinical severities were also compared statistically with the CIELAB values. RESULTS: As with the green illuminator, the correlation analysis of whole sites showed that the L* value positively correlated with age (r = 0.18677, P < 0.05), and that the a* value has negative and positive relationships with age (r = -0.20528, P < 0.05) and glossiness (r = 0.20885, P < 0.05) respectively. CONCLUSION: The correlations between CIELAB values and multiple characteristics of skin were more significant when green LED was applied than when white light was applied. In addition, coherent relationships between the grade of dryness and skin conductance values showed that visual assessment could be appropriate for the study as with objective measurement.
Subject(s)
Colorimetry/instrumentation , Galvanic Skin Response/physiology , Lighting/instrumentation , Photography/instrumentation , Refractometry/instrumentation , Skin/anatomy & histology , Adult , Color , Dermoscopy/instrumentation , Dermoscopy/methods , Electric Conductivity , Equipment Design , Equipment Failure Analysis , Female , Humans , Lighting/methods , Male , Photography/methods , Refractometry/methods , Reproducibility of Results , Semiconductors , Sensitivity and Specificity , Young AdultABSTRACT
BACKGROUND: Botulinum toxins have been widely used in cosmetic dermatology. Neurotoxin from the CBFC26 strain (NTC) is a recently developed botulinum toxin type A product manufactured through refined procedures. OBJECTIVE: A double-blinded, randomized, multicentre-designed, phase III trial to investigate the non-inferiority of NTC to existing botulinum toxin A, onabotulinumtoxin A in the treatment of moderate to severe glabellar lines. METHODS: A total of 272 subjects were randomized in a 1 : 1 ratio to receive 20 U of NTC or onabotulinumtoxin A. The primary endpoint was the response rate of physicians' assessment (PA) using the Facial Wrinkle Scale at week 4. The secondary endpoints included the response rate of PA at weeks 8, 12 and 16, and photographic assessment at weeks 4, 8, 12 and 16. Subjects' improvement assessment and subjective self-satisfaction levels were also investigated. RESULTS: Response rates for maximum frown were 89.3% in the NTC group and 81.9% in the onabotulinumtoxin A group at week 4. NTC also resulted in comparable results for both the response rates of the other evaluation points and incidence of adverse events compared to those of onabotulinumtoxin A. In subjects' improvement assessment and photographic evaluations, NTC even demonstrated better results compared with onabotulinumtoxin A in the early phase after treatment. Analysis of these results strongly supports the non-inferiority of NTC to onabotulinumtoxin A in the efficacy and safety. CONCLUSION: NTC is as effective as onabotulinumtoxin A in the treatment of glabellar lines, and both products were well tolerated.
Subject(s)
Botulinum Toxins, Type A/therapeutic use , Skin Aging/drug effects , Adult , Aged , Botulinum Toxins, Type A/adverse effects , Botulinum Toxins, Type A/pharmacology , Double-Blind Method , Face , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
BACKGROUND AND PURPOSE: Globus sensation is common and difficult to treat. The purpose of our study was to compare the diagnostic and therapeutic efficacy of barium esophagram and neck CT in patients with isolated globus sensation, to determine which of these modalities should be preferred in the evaluation of this condition. MATERIALS AND METHODS: We retrospectively identified patients presenting with isolated globus sensation from January 1, 2005, to December 31, 2012, who underwent neck CT or barium esophagram. We calculated the proportion of patients with abnormal findings, tabulated the nature of the abnormality, and reviewed the medical records to determine whether imaging changed management. RESULTS: One hundred forty-eight neck CTs and 104 barium esophagrams were included. Five (3.4%) patients with neck CTs and 4 (3.9%) with barium esophagrams demonstrated significant findings related to the history of globus sensation. Of these, 1 (0.7%) neck CT and 1 (1.0%) barium esophagram resulted in a change in clinical management. CONCLUSIONS: Imaging evaluation of the patient with uncomplicated globus sensation is unlikely to identify clinically significant imaging findings and is very unlikely to result in a change in clinical management, with a combined therapeutic efficacy of 0.8%. Thus, the routine use of imaging in the evaluation of patients with globus sensation cannot be recommended.
Subject(s)
Barium Sulfate , Esophageal Diseases/diagnostic imaging , Esophagus/diagnostic imaging , Neck/diagnostic imaging , Sensation Disorders/diagnostic imaging , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Aged, 80 and over , Contrast Media , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Young AdultABSTRACT
OBJECTIVES: Activation of the Wnt/ß-catenin signaling pathway inhibits adipogenesis by maintaining preadipocytes in an undifferentiated state. We investigated the effect of indirubin-3'-oxime (I3O), which was screened as an activator of the Wnt/ß-catenin signaling, on inhibiting the preadipocyte differentiation in vitro and in vivo. METHODS: 3T3L1 preadipocytes were differentiated with 0, 4 or 20 µM of I3O. The I3O effect on adipocyte differentiation was observed by Oil-red-O staining. Activation of Wnt/ß-catenin signaling in I3O-treated 3T3L1 cells was shown using immunocytochemical and immunoblotting analyses for ß-catenin. The regulation of adipogenic markers was analyzed via real-time reverse transcription-PCR (RT-PCR) and immunoblotting analyses. For the in vivo study, mice were divided into five different dietary groups: chow diet, high-fat diet (HFD), HFD supplemented with I3O at 5, 25 and 100 mg kg(-1). After 8 weeks, adipose and liver tissues were excised from the mice and subject to morphometry, real-time RT-PCR, immunoblotting and histological or immunohistochemical analyses. In addition, adipokine and insulin concentrations in serum of the mice were accessed by enzyme-linked immunosorbent assay. RESULTS: Using a cell-based approach to screen a library of pharmacologically active small molecules, we identified I3O as a Wnt/ß-catenin pathway activator. I3O inhibited the differentiation of 3T3-L1 cells into mature adipocytes and decreased the expression of adipocyte markers, CCAAT/enhancer-binding protein α and peroxisome proliferator-activated receptor γ, at both mRNA and protein levels. In vivo, I3O inhibited the development of obesity in HFD-fed mice by attenuating HFD-induced body weight gain and visceral fat accumulation without showing any significant toxicity. Factors associated with metabolic disorders such as hyperlipidemia and hyperglycemia were also improved by treatment of I3O. CONCLUSION: Activation of the Wnt/ß-catenin signaling pathway can be used as a therapeutic strategy for the treatment of obesity and metabolic syndrome and implicates I3O as a candidate anti-obesity agent.
Subject(s)
Adipogenesis/drug effects , Anti-Obesity Agents/pharmacology , Indoles/pharmacology , Metabolic Syndrome/metabolism , Obesity/metabolism , Oximes/pharmacology , Wnt Signaling Pathway/drug effects , 3T3-L1 Cells/drug effects , Adipocytes/drug effects , Adipocytes/metabolism , Animals , Cell Differentiation/drug effects , Diet, High-Fat , Male , Medicine, Chinese Traditional , Metabolic Syndrome/drug therapy , Mice , Obesity/drug therapy , Polymerase Chain Reaction/methodsABSTRACT
BACKGROUND: Keloids develop due to the overgrowth of fibrous tissue. Currently, there is no gold standard treatment for keloids and hypertrophic scars (HTS). Their propensity for local invasion and recurrence has prompted many investigations on antineoplastic agents. OBJECTIVES: To investigate the efficacy of topical and intralesional mitomycin C for the treatment of keloids and HTS. METHODS: Nine patients with clinically diagnosed keloids and HTS were treated using topical mitomycin C (1 mg/mL) for 3 min after shaving excision. The Vancouver Scars Scale, patient satisfaction, and adverse effects were checked after 6 months. The keloids and HTS were photographed at each monthly visit. Intralesional mitomycin C (1 mg/mL) was administered to study the effect on the regression of keloids in 2 patients. RESULTS: Application of mitomycin C to the base of shave-removed keloids and HTS showed good results. Six out of 9 patients were very satisfied with the outcome of treatment; none were disappointed. The results of intralesional mitomycin C treatment were disappointing. Both cases worsened, with increased ulceration after treatment. CONCLUSIONS: Topical application of mitomycin C following shaving excision was safe and effective for the treatment of keloids and HTS. However, intralesional mitomycin C therapy aggravated both lesions.
Subject(s)
Cicatrix, Hypertrophic/drug therapy , Keloid/drug therapy , Mitomycin/therapeutic use , Administration, Topical , Adolescent , Adult , Aged , Female , Humans , Injections, Intralesional , Male , Middle Aged , Mitomycin/administration & dosage , Patient SatisfactionABSTRACT
Owing to its tumor tropism and prolonged transgene expression, mesenchymal stem cell (MSC) has been considered as an ideal delivery vehicle for cancer gene therapies or therapeutic vaccines. In this study, we demonstrated that intratumoral (i.t.) injection of MSCs expressing modified interleukin-12 (MSCs/IL-12M) exhibited stronger tumor-specific T-cell responses and antitumor effects as well as more sustained expressions of IL-12 and interferon (IFN)-γ in both sera and tumor sites than did IL-12M-expressing adenovirus (rAd/IL-12M) in mice bearing both solid and metastatic tumors. Subcutaneous (s.c.) injection of MSCs/IL-12M at contralateral site of tumor exhibited similar levels of serum IL-12 and IFN-γ as i.t. injection, but much weaker antitumor effects in both B16F10 melanoma and TC-1 cervical cancer models than i.t. injection. Although intravenous (i.v.) injection elicited earlier peak serum levels of cytokines, it induced weaker tumor-specific T-cell responses and antitumor effects than i.t. injection, indicating that serum cytokine levels are not surrogate indicators of antitumor effects. Taken together, these results indicated that MSC is more efficient than adenovirus as a cytokine gene delivery vehicle and that i.t. injection of MSCs/IL-12M is the best approach to induce strong tumor-specific T-cell responses that correlate with anti-metastatic effects as well as inhibition of solid tumor growth, although MSCs themselves have an ability to migrate into the tumor site. In addition, MSCs/IL-12M embedded in Matrigel (MSCs/IL-12M/Matrigel) exhibited significant antitumor effects even in immunodeficient mice such as SCID and BNX mice lacking T, B and natural killer (NK) cells, but not in IFN-γ knockout mice. Our findings provide an optimal approach for designing an efficient clinical protocol of MSC-based cytokine gene therapy to induce strong tumor-specific T-cell responses and therapeutic anticancer efficacy.
Subject(s)
Gene Transfer Techniques , Interleukin-12/genetics , Mesenchymal Stem Cell Transplantation , Neoplasms/therapy , T-Lymphocytes/immunology , Adenoviridae/genetics , Animals , Cell Line, Tumor , Female , Immunotherapy/methods , Injections, Intravenous , Injections, Subcutaneous , Interferon-gamma/blood , Interferon-gamma/genetics , Interleukin-12/blood , Lung Neoplasms/secondary , Lung Neoplasms/therapy , Mice , Mice, Inbred C57BLABSTRACT
The objective of this study was to evaluate the ozone oxidation of dissolved heavy metals in an abandoned mine drainage (AMD) by conducting a pilot-scale operation at two different ozone doses of 7.5 and 24.0 g O(3)/h into an ozone reactor. A portion of the abandoned mine drainage near the Jungam Mine in Samchuck, Korea was pumped into this pilot-scale plant and used as an influent for the ozone oxidation. Some possible precipitates of metal oxides and hydroxides that resulted from the pilot-scale ozone oxidation of the dissolved Fe and Mn ions in the AMD (with a hydraulic retention time of 106 seconds in the ozone reactor) were effectively removed via sand filtration. A six-hour ozone oxidation with an ozone dose of 24.0 g O(3)/h and subsequent sand filtration, before backwashing the sand filter bed, can meet Korean drinking water quality standards (less than 0.3 mg/L) for Fe and Mn in the sand filter effluent under the operating conditions that were used in this study. The SO(4)(-2) concentrations and alkalinities of the influents were not affected by the ozone oxidation. The pH values of the influents were neutral or slightly alkaline, and after the six-hour oxidation, increased very slightly. These experiment results show that the ozone oxidation of dissolved heavy metals and the subsequent sand filtration of metal precipitates are desirable alternatives to removing heavy metals in an abandoned mine drainage.
Subject(s)
Industrial Waste/analysis , Metals, Heavy/chemistry , Mining , Ozone , Waste Disposal, Fluid/methods , Oxidation-Reduction , Pilot ProjectsABSTRACT
The first plasma with target values of the plasma current and the pulse duration was finally achieved on June 13, 2008 in the Korea Superconducting Tokamak Advanced Research (KSTAR). The diagnostic systems played an important role in achieving successful first plasma operation for the KSTAR tokamak. The employed plasma diagnostic systems for the KSTAR first plasma including the magnetic diagnostics, millimeter-wave interferometer, inspection illuminator, H(alpha), visible spectrometer, filterscope, and electron cyclotron emission (ECE) radiometer have provided the main plasma parameters, which are essential for the plasma generation, control, and physics understanding. Improvements to the first diagnostic systems and additional diagnostics including an x-ray imaging crystal spectrometer, reflectometer, ECE radiometer, resistive bolometer, and soft x-ray array are scheduled to be added for the next KSTAR experimental campaign in 2009.
ABSTRACT
Cell-permeable peptides (CPPs) promote the transduction of nonpermissive cells by recombinant adenovirus (rAd) to improve the therapeutic efficacy of rAd. In this study, branched oligomerization of CPPs significantly enhanced the transduction of human mesenchymal stem cells (MSCs) by rAd in a CPP type-independent manner. In particular, tetrameric CPPs increased transduction efficiency at 3000-5000-fold lower concentrations than did monomeric CPPs. Although branched oligomerization of CPPs also increases cytotoxicity, optimal concentrations of tetrameric CPPs required for maximum transduction are at least 300-1000-fold lower than those causing 50% cytotoxicity. Furthermore, although only approximately 60% of MSCs were maximally transduced at 500 muM of monomeric CPPs, >95% of MSCs were transduced with 0.1 muM of tetrameric CPPs. Tetrameric CPPs also significantly increased the formation and net surface charge of CPP/rAd complexes, as well as the binding of rAd to cell membranes at a greater degree than did monomeric CPPs, followed by rapid internalization into MSCs. In a critical-size calvarial defect model, the inclusion of tetrameric CPPs in ex vivo transduction of rAd expressing bone morphogenetic protein 2 into MSCs promoted highly mineralized bone formation. In addition, MSCs that were transduced with rAd expressing brain-derived neurotrophic factor in the presence of tetrameric CPPs improved functional recovery in a spinal cord injury model. These results demonstrated the potential for tetrameric CPPs to provide an innovative tool for MSC-based gene therapy and for in vitro gene delivery to MSCs.
Subject(s)
Adenoviridae/genetics , Cell-Penetrating Peptides/chemistry , Genetic Therapy/methods , Mesenchymal Stem Cells/metabolism , Transduction, Genetic/methods , Animals , Bone Diseases/genetics , Bone Diseases/therapy , Bone Morphogenetic Protein 2/genetics , Gene Transfer Techniques , Genetic Vectors , Humans , Male , Mesenchymal Stem Cells/cytology , Osteogenesis/genetics , Rats , Rats, Sprague-Dawley , Skull/growth & developmentABSTRACT
BACKGROUND: A light-coloured iris is considered a risk factor for skin cancer in general. However, iris colour cannot be considered a plausible risk factor for skin cancer in East Asian populations because of the relative homogeneity of iris colours. Furthermore, subjective classifications of iris colour cannot distinguish between different East Asian individuals as to their likelihood of developing cancer. AIM: To measure human iris colours quantitatively and to assess the significances of iris colours with respect to skin cancer in Korean patients. METHODS: Reference Commission Internationale d'Eclairage (CIE) L*a*b* coordinates on a ColorCheck chart were recorded using a reflectance spectrophotometer and compared with computed CIE L*a*b* coordinates from digital images to determine equations to calibrate CIE L*a*b* values. We then took iris images and measured iris colours and the colours of sun-exposed and sun-protected skin in 42 Korean patients with various cutaneous malignancies and nonmalignant dermatological diseases. Results were statistically analysed with regard to iris and skin colours in CIE L*a*b* coordinates. RESULTS: Patients with skin cancer had significantly lighter irises or higher L* values than dermatological patients without a malignancy (P = 0.02). Colour differences (ΔE*ab) between sun-exposed skin and sun-protected skin were greater in men (P < 0.01) and in patients with skin cancer (P < 0.01), and the lightness (L*) values of sun-exposed skins decreased with age (r = -0.32, P < 0.05). CONCLUSIONS: Iris colour appears to be a possible skin cancer risk factor in East Asian populations. The larger colour differences seen between sun-protected and sun-exposed skin in men and in patients with skin cancer may have been due to chronic or excessive sun exposure.