Sang Min Yi

Assessment of penetration of quantum dots through in vitro and in vivo human skin using the human skin equivalent model and the tape stripping method.

Quantum dots (QDs) are rapidly emerging as an important class of nanoparticles (NPs) with potential applications in medicine. However, little is known about penetration of QDs through human skin. This study investigated skin penetration of QDs in both in vivo and in vitro human skin. Using the tape stripping method, this study demonstrates for the first time that QDs can actually penetrate through the stratum corneum (SC) of human skin. Transmission electron microscope (TEM) and energy diverse X-ray (EDX) analysis showed accumulation of QDs in the SC of a human skin equivalent model (HSEM) after dermal exposure to QDs. These findings suggest possible transdermal absorption of QDs after dermal exposure over a relatively long period of time.

Analysis for the potential of polystyrene and TiO2 nanoparticles to induce skin irritation, phototoxicity, and sensitization.

The human skin equivalent model (HSEM) is well known as an attractive alternative model for evaluation of dermal toxicity. However, only limited data are available on the usefulness of a HSEM for nanotoxicity testing. This study was designed to investigate cutaneous toxicity of polystyrene and TiO2 nanoparticles using cultured keratinocytes, a HSEM, and an animal model. In addition, we also evaluated the skin sensitization potential of nanoparticles using a local lymph node assay with incorporation of BrdU. Findings from the present study indicate that polystyrene and TiO2 nanoparticles do not induce phototoxicity, acute cutaneous irritation, or skin sensitization. Results from evaluation of the HSEMs correspond well with those from animal models. Our findings suggest that the HSEM might be a useful alternative model for evaluation of dermal nanotoxicity.

Gender‐specific association of androgenetic alopecia with metabolic syndrome in a middle‐aged Korean population

Background  Although several previous studies have investigated the association between metabolic syndrome (MetS) and androgenetic alopecia (AGA), the study results have been inconsistent.

A Prospective, Long-Term Follow-Up Study of 1,444 nm Nd:YAG Laser: A New Modality for Treating Axillary Bromhidrosis

Background Surgery for bromhidrosis has a high risk of complications such as hematoma and necrosis. New nonsurgical methods may reduce the burden on surgery and the risks for the patient. Objective This study was performed to evaluate the efficacy and side-effects of the 1,444 nm Nd:YAG interstitial laser for treating axillary bromhidrosis. Methods Eighteen bromhidrosis patients were treated with a 1,444 nm Nd:YAG laser at Korea University Ansan Hospital. The post-treatment follow-up was 6 months. After the procedure, we confirmed apocrine gland destruction through histopathological examination. At each follow-up, we measured the severity of the remaining odor, postoperative pain, degree of mobility restriction, and overall satisfaction. Results After 180 days of follow-up, malodor elimination was good in 20 axillae, fair in 12 axillae, and poor in four axillae. At the end point of the study, 14 patients were totally satisfied with the laser treatment, three patients were partially satisfied, and one patient was disatisfied. Pain and limitation of mobility were significantly reduced within 1 week post-operatively, and were almost resolved within 4 weeks post-operatively. A histopathological examination revealed decreased density and significant alterations to the apocrine glands. Conclusion Subdermal coagulation treatment with a 1,444 nm Nd:YAG interstitial laser may be a less invasive and effective therapy for axillary bromhidrosis.

Successful Treatment of Multiple Cutaneous Neurofibromas Using a Combination of Shave Excision and Laser Photothermocoagulation with a 1,444-nm Neodymium-Doped Yttrium Aluminum Garnet Laser

Neurofibromatosis type 1 (NF-1) is an autosomal-dominant disorder of chromosome 17q11.2. Multiple cutaneous neurofibromas, one of the most characteristic clinical features, are mainly a cosmetic problem. Because of their sheer number and visibility, cutaneous neurofibromas are a major source of morbidity and psychological concern in NF-1, and most patients are willing to undergo removal of as many neurofibromas as possible. Although excision could completely remove the neurofibroma, it is time consuming and painful, and treatment of dozens of lesions at the same time is difficult.

Subdermal Coagulation Treatment of Axillary Bromhidrosis by 1,444 nm Nd:YAG Laser: A Comparison with Surgical Treatment

Bromhidrosis is a disease presenting as malodor caused by interaction between the discharge of apocrine glands and bacteria. The main therapeutic modalities are applying topical agents, liposuction surgery, and elective surgery. Among these, elective surgery is reported to be most effective. However, the efficiency largely depends on surgical technique. Additionally, other side effects, such as hematoma and scarring, are occasionally reported. Currently, CO2 laser and 1,064 nm Nd:YAG laser therapy are used, but as the wavelength is not specific to apocrine glands, these laser therapies have certain limitations. Recently, a 1,444 nm wavelength Accusculpt™ laser (LutronicCorp., Seoul, Korea) has been developed which is now commonly used for facial fat plasty and laser liposuction therapy. The use of this laser for bromhidrosis therapy targeting apocrine sweat glands is currently being discussed. Still, no studies on practical clinical use and side effects of this 1,444 nm wavelength laser have been published. In this report, we treated one bromhidrosis patient with 1,444 nm wavelength Accusculpt™ laser therapy on one side while conventional surgery was performed on the other side using a modified Inabas method. We compared the efficacy of this laser therapy to the surgical modality by measuring malodor severity and overall satisfaction by questionnaire. We also checked for other complications and recurrence for 12 months after the treatment. This patient was largely satisfied as it has a much shorter down time with the same therapeutic outcome. As subdermal coagulation treatment by 1,444 nm Nd:YAG laser may be less invasive but effective therapy, we would like to recommend this modality as a possible treatment option.

New Alternative Combination Therapy for Recalcitrant Common Warts: The Efficacy of Imiquimod 5% Cream and Duct Tape Combination Therapy

Dear Editor: Although verruca vulgaris (a common wart) is highly prevalent, but its treatment method is still not accepted by both patients and doctors1. Current modalities depend on the ablation of warts (cryotherapy, laser vaporization, electrodesiccation, salicylic acid, silver nitrate and trichloroacetic acid) or the interruption of cell division (podofilox, intralesional or systemic interferon, intralesional bleomycin and 5-fluorouracil)2,3. All contemporary therapies are connected to significant pain, tissue destruction and common recurrence2,3. No accessible drug therapy is known to successfully eradicate viral infection or replication. Until now, imiquimod, 1-(2-methylpropyl)-1Himidazo[4,5-c]-quinolin-4-amine has been used as a topical immune response to effectively treat external anogenital warts4. Because cell mediated immunity is the primary mechanism accountable for the regression of warts5, we accessed imiquimod as a promising therapy for these frequent viral diseases. In addition, several reports6,7 have recommended that occlusion with adhesive tape could also be an efficacious therapy for the treatment of warts. Given that duct tape therapy is economical and painless, we decided to use this method. The aim of this study was to estimate the safety, tolerance and effectiveness of combination therapy with imiquimod and duct tape for the treatment of the common verruca that have been resistant to prior treatment options. This was a phase II, open-label, clinical study. Approval of the Institutional Review Board (Approved No. AS10101) was obtained prior to the initiation of the study, and written consent was obtained from all patients prior to enrollment. Inclusion criteria were the following: (1) ability to understand and provide informed consent; (2) age greater than 18 years; (3) having at least 1 common wart with a diameter of 2 to 15 mm; and (4) lesions recalcitrant to prior reiterated medical and/or destructive treatment and patient denial to go through painful treatment. Fifty patients were enrolled in the study. Ten patients, 5 from the petrolatum group and 5 from the imiquimod 5% cream group, were not available for follow-up and thus were not included in the analysis. Patients obtained either petrolatum or imiquimod 5% cream. Imiquimod 5% cream or petrolatum was instructed to be self-applied, and then the wart was occluded with duct tape (Silver Duct Tape; 3M, St. Paul, MN, USA) by the patient once daily for 5 days per week. Patients were requested to apply either petrolatum or imiquimod 5% cream to the lesions in an amount that could be rubbed into the skin. In addition, a supply of standard duct tape was provided. The tape was left off in the daytime and reapplied the following night. The therapy proceeded for a maximum of 16 weeks or until resolution of the wart. Patients were asked to revisit the hospital every 2 weeks, so the doctor could remeasure the wart and document the results on the data sheet. Statistical analysis of response to treatment was performed using Fishers exact test, with p≤0.05 being considered significant. Of 40 patients who completed the study, 20 were in the petrolatum arm, and 20 were in the imiquimod 5% cream arm. There were no significant differences in the mean age or sex of the patients or in baseline size or location of the warts between the two groups. We found that imiquimod 5% cream and duct tape occlusion therapy was appreciably more effective than petrolatum and duct tape occlusion therapy. Eight (40%) of 20 patients in the imiquimod 5% cream and duct tape occlusion arm had complete resolution of their warts (Fig. 1) vs. 0 (0%) of 20 patients in the petrolatum and duct tape occlusion therapy arm (p=0.05). In addition, 6 patients (30%) enrolled in the imiquimod arm vs. 4 patients (20%) enrolled in the petrolatum arm had partial resolution (>50% size reduction) of their warts (Table 1). No recurrence of warts occurred during a follow-up period of 16 weeks. Although no major complications were noted in either group, the main adverse effects were erythema and itching sensation at the site. Fig. 1 Common warts before (A) and after (B) treatment with imiquimod 5% cream and duct tape occlusion therapy: complete response. Table 1 Treatment outcome of imiquimod 5% cream and duct tape occlusion therapy and petrolatum and duct tape occlusion therapy (p=0.05) In our study, we found that imiquimod 5% cream and duct tape occlusion therapy was more effective than petrolatum and duct tape occlusion therapy for the treatment of common warts. The mechanism of action of imiquimod in humans has not been exactly recognized, but several reports imply that it stimulates the cellular immune system, including the use of specific cytokines4,8. Through induction of interferon-alpha, imiquimod could improve antigen presentation by increasing the expression of major histocompatibility complex class I. Together with induced interleukin (IL)-12 p40, imiquimod augments the development of a Th1 type immune response. Other cytokines that are induced by imiquimod such as tumor necrosis factor-alpha, IL-1 and IL-6 may contribute to wart regression by increasing T-cell trafficking to the epidermis, enhancing natural killer cell cytotoxicity and stimulating B-cell proliferation. The therapeutic mechanism of duct tape for the treatment of verruca vulgaris has been mostly undetermined, but several theories have been proposed. The lay media often proposes the theory that occlusion results in a deprivation of oxygen to the virus, essentially leading to suffocation. A second theory is that duct tape debrides and debulks the wart. Allen and Dveirin9 suggested that duct tape may contribute to psychological aspects, thus, it may be more helpful in children than in adults. Additionally, duct tape occlusion creates a macerating and keratolytic environment10, which encourages penetration of imiquimod 5% cream. Thick stratum corneum may inhibit drug penetration, rendering the degree of keratinization, which is a possible explanation for the less impressive results on the common wart. Consequently, duct tape occlusion following the application of imiquimod may be helpful in overcoming this limitation. In conclusion, imiquimod 5% cream and duct tape occlusion combination therapy is an effective alternative treatment modality for the treatment of the common verruca. Additional studies with larger numbers of patients including randomized double blind trials are required to establish its effectiveness.

Single-Stage Reconstruction of Nasal Ala and Perialar Defect with Island Pedicle Flap and Burow's Graft

Basal cell carcinoma was diagnosed after histopathological examination that revealed basaloid cell tumor infiltration of the dermis with peripheral palisading. After the first stage of Mohs micrographic surgery with a 4-mm margin from the lesion, second-stage excision was performed toward the nasal tip. The frozen section taken after the second-stage excision with a 2-mm margin showed a negative resection margin of the tumor. As a result, a polygonal-shaped defect measuring 1.9 1.4 cm was created in the right nasal ala-perialar area (Figure 2). How would you repair this defect?

Hidden tuberculous lymphadenitis and miliary tuberculosis in an erythema induratum patient: Usefulness of interferon-γ release assays in the diagnosis

1 Barnes P, Bloch A, Davidson P, Snider DJ. Tuberculosis in patients with human immunodeficiency virus infection. N Engl J Med 1991; 324: 1644–1650. 2 Schermer DR, Simpson CG, Haserick JR, Van Ordstrand HS. Tuberculosis cutis miliaris acuta generalisata. Report of a case in an adult and review of the literature. Arch Dermatol 1969; 99: 64–69. 3 Fari~ na M, Gegundez M, Piqu e E et al. Cutaneous tuberculosis: a clinical, histopathologic, and bacteriologic study. J Am Acad Dermatol 1995; 33: 433–440. 4 del Giudice P, Bernard E, Perrin C et al. Unusual cutaneous manifestations of miliary tuberculosis. Clin Infect Dis 2000; 30: 201–204. 5 Daikos G, Uttamchandani R, Tuda C et al. Disseminated miliary tuberculosis of the skin in patients with AIDS: report of four cases. Clin Infect Dis 1998; 27: 205–208.

A case of squamous cell carcinoma and arsenic keratoses in a patient with vitiligo taking Chinese arsenic medicine

Chronic arsenic intoxication can still be found in environmental and industrial settings. The trivalent inorganic form of arsenic is known to be carcinogenic. Drinking water contaminated with inorganic arsenic is the primary route of exposure, and diet or medication is another major source of arsenic. We herein report a case of squamous cell carcinoma (SCC) from arsenic keratosis due to chronic ingestion of arsenical herbal medicine for vitiligo.