Entity

Time filter

Source Type

Torrance, CA, United States

Shin J.,Yonsei University | Lee J.S.,Yonsei University | Hann S.-K.,DRS Research | Oh S.H.,Yonsei University
British Journal of Dermatology | Year: 2012

Background Vitiligo is a common acquired depigmentation disorder caused by the loss of melanocytes. Despite the numerous treatment modalities available for vitiligo, responses to treatment are still unsatisfactory. For this reason, new treatment modalities and approaches are needed. Objectives To investigate the effects of fractional carbon dioxide (CO 2) laser therapy followed by systemic narrowband ultraviolet B (NB-UVB) phototherapy on nonsegmental vitiligo (NSV) as a prospective and randomized left-right comparative study. Methods Ten patients with NSV who presented symmetrical vitiligo lesions with no further improvement despite more than 1 year of conventional treatment were enrolled. Two sessions of half-body fractional CO 2 laser therapy were performed at a 2-month interval. NB-UVB phototherapy was then administered to the entire body 5 days after each fractional laser treatment twice a week, increasing the dose incrementally by 15% at each session. Objective clinical assessments were made by two blinded dermatologists using a quartile grading scale, and the patients' overall satisfaction was evaluated using a 10-point visual analogue scale. Results Two months after the last treatment, mean improvement scores, assessed by physicians, were significantly higher for those treated with half-body fractional CO 2 laser therapy followed by NB-UVB phototherapy, compared with those treated with NB-UVB alone (P = 0·034). In addition, according to subjective assessment, the half-body laser treatment followed by NB-UVB showed significantly higher improvements compared with NB-UVB treatment alone (P = 0·023). Noticeable adverse events, such as infection, scarring and Koebner phenomenon, were not found in any patient. Conclusions This study suggests that fractional CO 2 laser therapy followed by NB-UVB phototherapy could be used effectively and safely as an alternative modality for the treatment of refractory vitiligo. © 2011 The Authors. BJD © 2011 British Association of Dermatologists. Source


Shin S.,Yonsei University | Hann S.-K.,DRS Research | Oh S.H.,Yonsei University
Photodermatology Photoimmunology and Photomedicine | Year: 2016

Background: For the treatment of vitiligo, narrowband UVB (NBUVB) light is considered the most effective for nonsegmental vitiligo, while excimer laser treatment is commonly used for localized vitiligo. However, treatment areas may potentially be missed with excimer laser treatment. Objective: We aimed to evaluate the effect of combinational treatment with NBUVB light and excimer laser on vitiligo. Methods: All patients were first treated with NBUVB; excimer laser was then applied in conjunction with NBUVB phototherapy due to a slow response or no further improvement with continuous NBUVB treatment alone. To minimize adverse effects, a fixed dose of NBUVB was administered, and the dose of excimer laser was increased based on patient response. Results: Among 80 patients, 54 patients showed responses after combination with excimer laser; however, 26 patients (32.5%) showed no remarkable change after combination therapy. Of the 26 patients who showed no further response, 12 patients (46.1%) presented with vitiligo on the acral areas, which are known to the least responsive sites. Conclusion: Our study suggests that combined treatment of NBUVB and excimer laser in vitiligo may enhance the treatment response without remarkable side effects, therefore might also increase the compliance of the patients to the treatment. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. Source


Kim D.-Y.,Yonsei University | Oh S.H.,Yonsei University | Hann S.-K.,DRS Research
British Journal of Dermatology | Year: 2011

Background: The origin of the distribution of segmental vitiligo (SV) has not yet been clearly elucidated. Segmental configurations of cutaneous disorders have been explained using two main interpretations, i.e. following either dermatomal or blaschkolinear distributions. However, facial SV does not always correspond to either of these distributions. Objectives: We classified facial SV into several distinctive subtypes according to specific distributions based on long-term observations. Methods: In total, 257 patients with facial SV were included, all of whom were closely observed for more than 1 year. The distribution patterns of facial SV were classified according to morphological similarities based on clinical observations. Results: The lesions of facial SV were categorized into six subtypes: types I-a and I-b, and types II-V. Type I-a and type IV broadly involved the mid-level face from the forehead to the lower cheek, but type IV lesions selectively appeared on the right side of the face and did not cross the midline. Type I-b lesions chiefly involved the forehead and scalp hair. Types II and III involved the lower face and, frequently, the neck area, and type V lesions were distributed mostly around the right orbital area. The most frequent type of lesion in this study was type I-a (28·8%), followed by types II (16·0%), III (14·4%), IV (10·9%), I-b (10·5%) and V (8·6%). Conclusions: Newly established patterns of facial SV may be valuable for certain aspects of prognosis, such as the likely degree and path of lesion spreading. © 2011 British Association of Dermatologists. Source


Elmasry H.,DRS Research
Journal of Head Trauma Rehabilitation | Year: 2016

OBJECTIVE:: To determine the preenlistment and early service risk factors for traumatic brain injury (TBI)-related disability in Army and Marine Corps service members. DESIGN:: Matched case-control design. MAIN OUTCOME:: TBI disability discharges. SUBJECTS:: Army and Marine Corps service members with an enlistment record and disability discharge for TBI were included as cases. Controls were selected from the enlisted population with no disability evaluation record and were matched on fiscal year of enlistment, sex, and service at a ratio of 5:1. RESULTS:: Older age at enlistment resulted in a significantly increased risk for TBI disability in the crude and adjusted models (adjusted odds ratio [aOR] = 1.49; 95% confidence interval [CI], 1.16-1.91). An enlistment military occupational specialty (MOS) with a combat arms designation resulted in an almost 3-fold increased odds of TBI disability compared with other MOS categories (aOR = 2.75; 95% CI, 2.46-3.09). This remained a significant risk factor for TBI disability in the multivariate model (aOR = 2.74; 95% CI, 2.45-3.08). CONCLUSION:: Results from this study help inform the existing body of military TBI research by highlighting the preenlistment demographic and early service risk factors for TBI disability. Further research into the role of age on TBI disability in the military is merited. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Source


Kim J.Y.,Yonsei University | Shin J.Y.,Yonsei University | Kim M.,Yonsei University | Hann S.-K.,DRS Research | Oh S.H.,Yonsei University
Journal of Dermatological Science | Year: 2012

Background: Cytosolic NADP +-dependent ICDH (IDPc) has an antioxidant effect as a supplier of NADPH to the cytosol, which is needed for the production of glutathione. Objective: To evaluate the expression of IDPc in melanocytes and to elucidate its role as an antioxidant. Methods: The knock-down of IDPc expression in immortalized mouse melanocyte cell lines (melan-a) was performed using the short interfering RNA (siRNA)-targeted gene silencing method. After confirming the silencing of IDPc expression with mRNA and protein levels, viability, apoptosis and necrosis, as well as ROS production in IDPc-silenced melanocytes were monitored under conditions of oxidative stress and non-stress. Also, the ratio of oxidized glutathione to total glutathione was examined, and whether the addition of glutathione recovered cell viability, decreased by oxidant stress, was checked. Results: The expression of IDPc in both primary human melanocytes and melan-a cells was confirmed by Western blot and RT-PCR. The silencing of IDPc expression by transfecting IDPc siRNA in melan-a cells was observed by Western blotting and real-time RT-PCR. IDPc knock-down cells showed significantly decreased cell viability and an increased number of cells under apoptosis and necrosis. IDPc siRNA-treated melanocytes demonstrated a higher intensity of DCFDA after the addition of H 2O 2 compared with scrambled siRNA-treated melanocytes, and a lower ratio of reduced glutathione to oxidized glutathione were observed in IDPc siRNA transfected melanocytes. In addition, the addition of glutathione recovered cell viability, which was previously decreased after incubation with H 2O 2. Conclusions: This study suggests that decreased IDPc expression renders melanocytes more vulnerable to oxidative stress, and IDPc plays an important antioxidant function in melanocytes. © 2011 Japanese Society for Investigative Dermatology. Source

Discover hidden collaborations