104 results on '"Hyuck Hoon Kwon"'
Search Results
2. Combined Fractional Treatment of Acne Scars Involving Non-ablative 1,550-nm Erbium-glass Laser and Micro-needling Radiofrequency: A 16-week Prospective, Randomized Split-face Study
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Hyuck Hoon Kwon, Hae Young Park, Sun Chul Choi, Youin Bae, Chanhee Kang, Jae Yoon Jung, and Gyeong-Hun Park
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acnescar ,fractionalphotothermolysis ,lasersurgery ,radiofrequency ,Dermatology ,RL1-803 - Abstract
An optimized therapeutic regimen involving a non-ablative fractionated laser or radiofrequency therapy for acne scars has not yet been established. To evaluate whether the combination of a non-ablative fractional laser (NAF) and fractional micro-needling radiofrequency (FMR) has clinical advantages for the treatment of atrophic acne scars compared with NAF alone, a 16-week prospective, randomized split-face study was performed. Each facial side of a patient was treated with 3 sessions of either NAF with FMR or NAF alone, with a 4-week interval between each session. Although both sides demonstrated significant decreases in the échelle d’évaluation clinique des cicatrices d’acné (ECCA) score, the facial side treated using the combination regimen demonstrated greater improvement in ECCA score regarding degree and onset time than the NAF-treated side. Histopathological and immunohistochemical results confirmed the clinical findings. This study demonstrated that a combination regimen involving NAF and FMR could be a viable option with satisfactory efficacy.
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- 2017
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3. Skin Brightening Efficacy of Exosomes Derived from Human Adipose Tissue-Derived Stem/Stromal Cells: A Prospective, Split-Face, Randomized Placebo-Controlled Study
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Byong Seung Cho, Jinah Lee, Yujin Won, Diane I. Duncan, Richard C. Jin, Joon Lee, Hyuck Hoon Kwon, Gyeong-Hun Park, Steven Hoseong Yang, Byung Cheol Park, Kui Young Park, Jinkwon Youn, Junsoo Chae, Minwoong Jung, and Yong Weon Yi
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adipose tissue-derived stem/stromal cells (ASCs) ,ASC-exosomes ,hyperpigmentation ,melanocyte ,skin brightening ,Chemistry ,QD1-999 - Abstract
Studies have shown that stem cells and their derivatives, including conditioned media (CM), have inhibitory effects on skin pigmentation. However, evidence supporting the skin brightening effect of exosomes derived from stem cells is lacking. We studied the antipigmentation effect in vitro and skin brightening efficacy in vivo of exosomes derived from human adipose tissue-derived mesenchymal stem/stromal cells (ASC-exosomes). Exosomes were isolated from the CM of ASCs using the tangential flow filtration method. ASC-exosomes reduced intracellular melanin levels in B16F10 melanoma cells regardless of the presence of the α-melanocyte-stimulating hormone (α-MSH). The skin brightening efficacy of a cosmetic formulation containing ASC-exosomes was assessed in human volunteers with hyperpigmentation in a prospective, split-face, double-blind, randomized placebo-controlled study. The ASC-exosome-containing formulation statistically decreased the melanin contents compared to the placebo control. However, the melanin-reduction activity was limited and diminished along with time. A further improvement in efficient transdermal delivery of ASC-exosomes will be helpful for more profound efficacy. In summary, these results suggest that ASC-exosomes can be used as a cosmeceutical for skin brightening.
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- 2020
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4. Mesenchymal Stem/Stromal Cell-Derived Exosomes for Immunomodulatory Therapeutics and Skin Regeneration
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Dae Hyun Ha, Hyun-keun Kim, Joon Lee, Hyuck Hoon Kwon, Gyeong-Hun Park, Steve Hoseong Yang, Jae Yoon Jung, Hosung Choi, Jun Ho Lee, Sumi Sung, Yong Weon Yi, and Byong Seung Cho
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anti-aging ,anti-inflammation ,hair growth ,immunomodulation ,mesenchymal stem cells (MSCs) ,MSC-exosomes ,Cytology ,QH573-671 - Abstract
Exosomes are nano-sized vesicles that serve as mediators for cell-to-cell communication. With their unique nucleic acids, proteins, and lipids cargo compositions that reflect the characteristics of producer cells, exosomes can be utilized as cell-free therapeutics. Among exosomes derived from various cellular origins, mesenchymal stem cell-derived exosomes (MSC-exosomes) have gained great attention due to their immunomodulatory and regenerative functions. Indeed, many studies have shown anti-inflammatory, anti-aging and wound healing effects of MSC-exosomes in various in vitro and in vivo models. In addition, recent advances in the field of exosome biology have enabled development of specific guidelines and quality control methods, which will ultimately lead to clinical application of exosomes. This review highlights recent studies that investigate therapeutic potential of MSC-exosomes and relevant mode of actions for skin diseases, as well as quality control measures required for development of exosome-derived therapeutics.
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- 2020
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- View/download PDF
5. Exosomes from Human Adipose Tissue-Derived Mesenchymal Stem Cells Promote Epidermal Barrier Repair by Inducing de Novo Synthesis of Ceramides in Atopic Dermatitis
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Kyong-Oh Shin, Dae Hyun Ha, Jin Ock Kim, Debra A. Crumrine, Jason M. Meyer, Joan S. Wakefield, Yerin Lee, Bogyeong Kim, Sungeun Kim, Hyun-keun Kim, Joon Lee, Hyuck Hoon Kwon, Gyeong-Hun Park, Jun Ho Lee, Jihye Lim, Sejeong Park, Peter M. Elias, Kyungho Park, Yong Weon Yi, and Byong Seung Cho
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asc-exosomes ,anti-inflammation ,atopic dermatitis ,restoration ,skin barrier ,lamella body ,ceramides ,Cytology ,QH573-671 - Abstract
Atopic dermatitis (AD) is a multifactorial, heterogeneous disease associated with epidermal barrier disruption and intense systemic inflammation. Previously, we showed that exosomes derived from human adipose tissue-derived mesenchymal stem cells (ASC-exosomes) attenuate AD-like symptoms by reducing multiple inflammatory cytokine levels. Here, we investigated ASC-exosomes’ effects on skin barrier restoration by analyzing protein and lipid contents. We found that subcutaneous injection of ASC-exosomes in an oxazolone-induced dermatitis model remarkably reduced trans-epidermal water loss, while enhancing stratum corneum (SC) hydration and markedly decreasing the levels of inflammatory cytokines such as IL-4, IL-5, IL-13, TNF-α, IFN-γ, IL-17, and TSLP, all in a dose-dependent manner. Interestingly, ASC-exosomes induced the production of ceramides and dihydroceramides. Electron microscopic analysis revealed enhanced epidermal lamellar bodies and formation of lamellar layer at the interface of the SC and stratum granulosum with ASC-exosomes treatment. Deep RNA sequencing analysis of skin lesions demonstrated that ASC-exosomes restores the expression of genes involved in skin barrier, lipid metabolism, cell cycle, and inflammatory response in the diseased area. Collectively, our results suggest that ASC-exosomes effectively restore epidermal barrier functions in AD by facilitating the de novo synthesis of ceramides, resulting in a promising cell-free therapeutic option for treating AD.
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- 2020
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6. Accelerated Particle Filter With GPU for Real-Time Ballistic Target Tracking.
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Daeyeon Kim, Yunho Han, Heoncheol Lee, Yunyoung Kim, Hyuck-Hoon Kwon, Chan Kim, and Wonseok Choi 0005
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- 2023
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7. Parallelized Particle Filter With Efficient Pipelining on FPGA for Real-Time Ballistic Target Tracking.
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Daeyeon Kim, Heoncheol Lee, Hyuck-Hoon Kwon, Yeji Hwang, and Wonseok Choi 0005
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- 2023
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8. Parallelized Particle Swarm Optimization on FPGA for Realtime Ballistic Target Tracking
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Juhyeon Park, Heoncheol Lee, Hyuck-Hoon Kwon, Yeji Hwang, and Wonseok Choi
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ballistic target tracking ,field-programmable gate array ,particle swarm optimization ,realtime system ,Chemical technology ,TP1-1185 - Abstract
This paper addresses the problem of tracking a high-speed ballistic target in real time. Particle swarm optimization (PSO) can be a solution to overcome the motion of the ballistic target and the nonlinearity of the measurement model. However, in general, particle swarm optimization requires a great deal of computation time, so it is difficult to apply to realtime systems. In this paper, we propose a parallelized particle swarm optimization technique using field-programmable gate array (FPGA) to be accelerated for realtime ballistic target tracking. The realtime performance of the proposed method has been tested and analyzed on a well-known heterogeneous processing system with a field-programmable gate array. The proposed parallelized particle swarm optimization was successfully conducted on the heterogeneous processing system and produced similar tracking results. Also, compared to conventional particle swarm optimization, which is based on the only central processing unit, the computation time is significantly reduced by up to 3.89×.
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- 2023
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9. Look-Angle-Shaping Guidance Law for Impact Angle and Time Control With Field-of-View Constraint.
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Hyeong-Geun Kim, Jun-Yong Lee, Hyoun Jin Kim, Hyuck-Hoon Kwon, and Jang-Seong Park
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- 2020
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10. Nonlinear missile autopilot design using a density function-based sum-of-squares optimization approach.
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Min-Won Seo, Hyuck-Hoon Kwon, and Han-Lim Choi
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- 2015
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11. Tightening and Reduction of Unwanted Submental Fat Using Triple-Layer High-Intensity Focused Ultrasound: Clinical and 3-Dimensional Imaging Analysis
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Jae Yoon Jung, Gyeong-Hun Park, Mira Choi, Hyuck Hoon Kwon, and Steven Hoseong Yang
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Adult ,Male ,Chin ,medicine.medical_specialty ,Triple layer ,Ultrasonic Therapy ,medicine.medical_treatment ,Cosmetic Techniques ,Dermatology ,Imaging, Three-Dimensional ,Rating scale ,medicine ,Humans ,Adverse effect ,Reduction (orthopedic surgery) ,business.industry ,General Medicine ,Middle Aged ,High-intensity focused ultrasound ,Regimen ,Three dimensional imaging ,medicine.anatomical_structure ,Adipose Tissue ,Female ,Surgery ,Radiology ,business - Abstract
Background Unwanted submental fat (SMF) is aesthetically unappealing, but methods of reduction are either invasive or lack evidence of their use. Objective The authors sought to evaluate the safety and efficacy of a novel triple-layer high-intensity focused ultrasound (HIFU) regimen for SMF reduction. Methods Forty Korean subjects with moderate/severe SMF were evaluated after receiving a session of triple-layer HIFU treatments (using 3.0-, 4.5-, and 6.0-mm focusing transducers). The objective evaluation based on the 5-point Clinician-Reported Submental Fat Rating Scale (CR-SMFRS) and patients' satisfaction based on the 7-point Subject Self-Rating Scale (SSRS) were determined 8 weeks after treatment. Three-dimensional image analysis was also performed. Results At the follow-up visit, the proportion of treatment responders defined as subjects with ≥1-point improvement in CR-SMFRS was 62.5%, and the proportion of patients satisfied with appearance of their face and chin (score ≥4 on the SSRS) was 67.5% of the total patients. The results of 3-dimensional analysis were consistent with clinical observations. Only mild and transient side effects were observed for some patients with no serious adverse effects. Conclusion The triple-layer HIFU regimen including the novel 6.0-mm transducer has benefits for tightening and rejuvenation of the area with unwanted SMF, showing reasonable safety profiles.
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- 2021
12. Exosomes derived from human adipose tissue‐derived mesenchymal stem cells for the treatment of dupilumab‐related facial redness in patients with atopic dermatitis: A report of two cases
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Jae Wan Park, Kui Young Park, Hyuck Hoon Kwon, Seong Jun Seo, Gyeong-Hun Park, and Hye Sung Han
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medicine.medical_specialty ,business.industry ,Mesenchymal stem cell ,Adipose tissue ,Mesenchymal Stem Cells ,Dermatology ,Atopic dermatitis ,Antibodies, Monoclonal, Humanized ,Exosomes ,medicine.disease ,Dupilumab ,Exosome ,Microvesicles ,Dermatitis, Atopic ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Double-Blind Method ,Facial redness ,030220 oncology & carcinogenesis ,medicine ,Humans ,In patient ,business - Abstract
Background Atopic dermatitis is a chronic, pruritic, and inflammatory dermatosis that affects approximately 20% of children and 10% of adults worldwide. Dupilumab facial redness is gaining attention as additional cases are coming to light in the medical literature. Objectives and methods Exosomes are nano-sized vesicles that are constantly released by almost all cells. They can travel between cells and transport their cargo (lipids, proteins, and nucleic acids), making them a possible cell-free therapeutic option for various diseases. Herein, we investigated whether topical application of human adipose tissue-derived mesenchymal stem cell-derived exosomes could reduce dupilumab facial redness in patients with severe atopic dermatitis. Results Two patients with atopic dermatitis and refractory dupilumab facial redness were successfully treated with electroporation-assisted topical application of human adipose tissue-derived mesenchymal stem cell-derived exosomes. Six repeated sessions of treatment, with an interval of 1 week between each session, led to marked improvement in erythematous facial lesions. Conclusions We suggest that human adipose tissue-derived mesenchymal stem cell-derived exosomes may serve as an effective agent in the management of dupilumab facial redness. However, further controlled studies with a larger number of patients are necessary to confirm the efficacy and safety of this agent, as well as the optimal treatment protocol.
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- 2021
13. Mid-course Trajectory Optimization for Boost-Glide Missiles Based on Convex Programming
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Seong-Min Hong, Gyeonghun Kim, Hyuck-Hoon Kwon, and Yoon-Hwan Kim
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Mathematical optimization ,Computer science ,Convex optimization ,Trajectory optimization ,Course (navigation) - Published
- 2021
14. L1 Penalized Sequential Convex Programming for Fast Trajectory Optimization: With Application to Optimal Missile Guidance
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Min-Jea Tahk, Young-Jae Oh, Ki-Jeong Kwon, Heekun Roh, and Hyuck-Hoon Kwon
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020301 aerospace & aeronautics ,0209 industrial biotechnology ,Mathematical optimization ,Computer science ,Computation ,Monte Carlo method ,Aerospace Engineering ,02 engineering and technology ,Trajectory optimization ,Missile guidance ,020901 industrial engineering & automation ,Missile ,0203 mechanical engineering ,Control and Systems Engineering ,Robustness (computer science) ,Convex optimization ,General Materials Science ,Pseudo-spectral method ,Electrical and Electronic Engineering - Abstract
In this paper, an L1 penalized sequential convex programming (LPSCP) method for trajectory optimization is proposed. Sequential convex methods dramatically reduce computation time for nonlinear trajectory optimizations, based on the desirable properties of convex optimization algorithms. Due to its fast convergence speed, the sequential convex method is considered as a near-future candidate for real-time optimal online guidance. However, the generic sequential convex method seldom suffers from poor robustness to crude the initial trajectory estimates and constraint perturbations, which limits its application to real-world systems. Suggested LPSCP method resolves the robustness issue of generic sequential convex methods, by addressing the convex subproblem infeasibility. While improving its robustness, proposed LPSCP method maintains its fast convergence property. Consequently, LPSCP method enhances overall versatility of sequential convex method for trajectory optimization, which includes ameliorated robustness toward initial trajectory estimates, and improved stability to state and constraint perturbations. Throughout the paper, details of LPSCP method are outlined along with an application example to missile trajectory optimization problems. Desirable properties of LPSCP method are demonstrated through several simulated examples. Optimized trajectories are compared with results from the pseudospectral method. Numerical simulation and Monte Carlo analysis show that LPSCP method accelerates optimization process dramatically (−98.2% on average) while producing the same optimal trajectory.
- Published
- 2019
15. A Convex Programming Approach to Mid-course Trajectory Optimization for Air-to-Ground Missiles
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Han-Lim Choi and Hyuck-Hoon Kwon
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Lossless compression ,Computer science ,Regular polygon ,Aerospace Engineering ,Trajectory optimization ,Solver ,Missile ,Terminal (electronics) ,Control and Systems Engineering ,Control theory ,Convex optimization ,Second-order cone programming ,General Materials Science ,Electrical and Electronic Engineering - Abstract
This paper addresses trajectory optimization in the mid-course phase of an air-to-ground missile, when the main objectives are (a) to ensure that the target is locked on in the center of the missile’s field-of-view at a specified flight path angle and (b) to attain maximum possible speed to allow for sufficient maneuverability in the terminal phase. The method presents as a second-order cone program (SOCP) formulation for this trajectory optimization, taking advantage of partial linearization and lossless convexification techniques that effectively handle underlying non-convex characteristics of the problem. A well-established SOCP solver can then be readily used to obtain the optimal solution to this convex program. The proposed approach is validated by (a) proving the losslessness of the convexification, and (b) numerically comparing the results with an existing pseudo-spectral method.
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- 2019
16. A Novel Combined Light-Based Treatment of Acne Vulgaris With 1,450-nm Diode Laser and 450-nm Blue Light
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Gyeong-Hun Park, Sun Chul Choi, Youin Bae, Jae-Yoon Jung, and Hyuck Hoon Kwon
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Treatment outcome ,Dermatology ,Severity of Illness Index ,law.invention ,Young Adult ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Randomized controlled trial ,law ,Acne Vulgaris ,Severity of illness ,medicine ,Humans ,Prospective Studies ,Low-Level Light Therapy ,Acne ,Diode ,Blue light ,business.industry ,General Medicine ,medicine.disease ,Laser ,Treatment Outcome ,Patient Satisfaction ,030220 oncology & carcinogenesis ,Female ,Surgery ,Lasers, Semiconductor ,business - Abstract
Nonablative 1,450-nm diode laser (DL) and visible blue light (BL) have been effectively used for acne with superior safety profiles.To evaluate synergistic effects of sequential DL and BL application for acne.A 20-week, randomized split-face study was conducted to compare clinical courses between 2 facial sides either receiving sequential application of DL and BL or BL alone in 24 patients with mild to moderate facial acne vulgaris. Patients were scheduled to receive 3 consecutive sessions at 4-week intervals. Objective assessments, including revised Leeds grades, lesion counts, and sebum output measurements, and patients' subjective satisfaction were investigated.Both combination and BL sides demonstrated steady improvement of inflammatory acne lesions with 62.3% and 35.2% decreases at the 12-week follow-up visit compared with baseline respectively. For noninflammatory lesions and seborrhea, only combination regimen demonstrated improvement. Patients' subjective assessments paralleled objective findings. For safety profiles, no severe adverse effect was observed on both sides, and mild symptoms resolved spontaneously within a day.The combination regimen demonstrated synergistic efficacies for acne and seborrhea, with satisfactory safety profiles. Therefore, a few sessions of these light-based applications would be a viable option for acne treatments.
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- 2019
17. Combined treatment of recalcitrant papulopustular rosacea involving pulsed dye laser and fractional microneedling radiofrequency with low‐dose isotretinoin
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Won-Yong Lee, Jae-Yoon Jung, Gyeong Hun Park, Youin Bae, and Hyuck Hoon Kwon
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Adult ,Male ,Laser surgery ,medicine.medical_specialty ,Erythema ,Side effect ,medicine.medical_treatment ,Administration, Oral ,Lasers, Dye ,Dermatology ,Severity of Illness Index ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Oral administration ,medicine ,Humans ,Low-Level Light Therapy ,Isotretinoin ,Retrospective Studies ,Dose-Response Relationship, Drug ,business.industry ,Retrospective cohort study ,Middle Aged ,Radiofrequency Therapy ,medicine.disease ,Combined Modality Therapy ,Regimen ,Treatment Outcome ,Needles ,Patient Satisfaction ,Rosacea ,030220 oncology & carcinogenesis ,Female ,medicine.symptom ,business ,Follow-Up Studies ,medicine.drug - Abstract
BACKGROUND While a considerable number of cases with papulopustular rosacea (PPR) are resistant to conventional medications, therapeutic regimens are not currently established. Pulsed dye laser (PDL) and fractional microneedling radiofrequency (FMR) have previously demonstrated satisfactory results for anti-angiogenesis, anti-inflammation, and dermal remodeling. AIMS To evaluate the efficacy and safety of novel combination regimen with low-dose oral isotretinoin, PDL, and FMR in the treatment of recalcitrant PPR. PATIENTS AND METHODS A retrospective study was undertaken for recalcitrant PPR patients to evaluate the clinical course of novel combination regimen. Twenty-five PPR patients who had failed in previous first-line therapies were enrolled. They were treated with three sessions of PDL and FMR consecutively at 4-week intervals, maintaining daily oral administration of 10 mg isotretinoin for 8 weeks. Objective assessments, erythema index measurement, and patients' subjective satisfaction were evaluated at each visit and 16 weeks after the final treatment. RESULTS At the final follow-up visit, the number of papules and pustules decreased by 71%, and erythema index by 54% compared with baseline (P
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- 2019
18. Clinical Evaluations of a Novel Thread Lifting Regimen Using Barbed Polyglyconate Suture for Facial Rejuvenation: Analysis Using a 3-Dimensional Imaging System
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Gyeong-Hun Park, Hyuck Hoon Kwon, Sun Chul Choi, and Jae-Yoon Jung
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Adult ,Esthetics ,Polymers ,Facial rejuvenation ,Dermatology ,Thread (computing) ,Aging face ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Imaging, Three-Dimensional ,0302 clinical medicine ,Humans ,Rejuvenation ,Medicine ,Aged ,Retrospective Studies ,Orthodontics ,Sutures ,business.industry ,Suture Techniques ,digestive, oral, and skin physiology ,Polyglyconate suture ,Soft tissue ,General Medicine ,Middle Aged ,Skin Aging ,body regions ,Three dimensional imaging ,Patient Satisfaction ,Face ,030220 oncology & carcinogenesis ,Rhytidoplasty ,Female ,Surgery ,Absorbable sutures ,business - Abstract
Thread lifting with absorbable sutures has recently gained prominence for rejuvenating ptotic and sagging soft tissues in aging face. A barbed, delayed absorbable polyglyconate monofilament shows significantly high tensile loads with superior flexibility and elasticity.To evaluate the safety and efficacy of novel thread lifting regimen with barbed polyglyconate suture for counteracting the descent and laxity of the aging face.A retrospective chart review was conducted for 25 Korean patients with mild to moderate facial skin laxity receiving thread lifting procedures using barbed polyglyconate suture. Dermatologists' objective assessments using a 5-point Global Aesthetic Improvement Scale (GAIS), 3D imaging system, and subjective satisfaction were recorded at baseline and 4 months after treatments.In most patients (84%), GAIS scores were more than score 3 ("improved"), with 40% of score 4 ("much improved") and 24% of score 5 ("excellent") at the follow-up point. Subjective assessments paralleled these patterns. Three-dimensional analysis quantitatively showed volume migration of low face upward, clinically interpreted as facial lifting. No serious adverse effect was observed.This novel thread lifting procedure using barbed polyglyconate suture is a safe and effective method for tightening and lifting for aging face with mild to moderate face sagging.
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- 2019
19. Skin Brightening Efficacy of Exosomes Derived from Human Adipose Tissue-Derived Stem/Stromal Cells: A Prospective, Split-Face, Randomized Placebo-Controlled Study
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Joon Lee, Jinah Lee, Richard C. Jin, Gyeong Hun Park, Kui Young Park, Steven Hoseong Yang, Byung Cheol Park, Minwoong Jung, Byong Seung Cho, Jinkwon Youn, Hyuck Hoon Kwon, Yong Weon Yi, Yujin Won, Diane I. Duncan, and Junsoo Chae
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adipose tissue-derived stem/stromal cells (ASCs) ,Aging ,Stromal cell ,melanocyte ,Pharmaceutical Science ,Adipose tissue ,Dermatology ,Pharmacology ,Melanocyte ,lcsh:Chemistry ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,In vivo ,medicine ,Chemical Engineering (miscellaneous) ,030304 developmental biology ,ASC-exosomes ,0303 health sciences ,integumentary system ,business.industry ,Mesenchymal stem cell ,Hyperpigmentation ,medicine.anatomical_structure ,lcsh:QD1-999 ,skin brightening ,hyperpigmentation ,Surgery ,medicine.symptom ,Stem cell ,business ,Cosmeceutical - Abstract
Studies have shown that stem cells and their derivatives, including conditioned media (CM), have inhibitory effects on skin pigmentation. However, evidence supporting the skin brightening effect of exosomes derived from stem cells is lacking. We studied the antipigmentation effect in vitro and skin brightening efficacy in vivo of exosomes derived from human adipose tissue-derived mesenchymal stem/stromal cells (ASC-exosomes). Exosomes were isolated from the CM of ASCs using the tangential flow filtration method. ASC-exosomes reduced intracellular melanin levels in B16F10 melanoma cells regardless of the presence of the &alpha, melanocyte-stimulating hormone (&alpha, MSH). The skin brightening efficacy of a cosmetic formulation containing ASC-exosomes was assessed in human volunteers with hyperpigmentation in a prospective, split-face, double-blind, randomized placebo-controlled study. The ASC-exosome-containing formulation statistically decreased the melanin contents compared to the placebo control. However, the melanin-reduction activity was limited and diminished along with time. A further improvement in efficient transdermal delivery of ASC-exosomes will be helpful for more profound efficacy. In summary, these results suggest that ASC-exosomes can be used as a cosmeceutical for skin brightening.
- Published
- 2020
20. Combination Treatment with Human Adipose Tissue Stem Cell-derived Exosomes and Fractional CO2 Laser for Acne Scars: A 12-week Prospective, Double-blind, Randomized, Split-face Study
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Byung Cheol Park, Steven Hoseong Yang, Hyuck Hoon Kwon, Gyeong Hun Park, Joon Lee, Kui Young Park, Jae-Yoon Jung, and Youin Bae
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0301 basic medicine ,medicine.medical_specialty ,Erythema ,Urology ,Adipose tissue ,Dermatology ,acne scar ,Exosomes ,Double blind ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Cicatrix ,0302 clinical medicine ,Double-Blind Method ,Acne Vulgaris ,Adjuvant therapy ,lcsh:Dermatology ,Medicine ,Humans ,Prospective Studies ,Low-Level Light Therapy ,Acne scars ,Co2 laser ,business.industry ,Stem Cells ,General Medicine ,adipose tissue stem cell-derived exosomes ,lcsh:RL1-803 ,Microvesicles ,030104 developmental biology ,Treatment Outcome ,Adipose Tissue ,Lasers, Gas ,fractional laser ,Stem cell ,medicine.symptom ,business - Abstract
A variety of applications of human adipose tissue stem cell-derived exosomes have been suggested as novel cell-free therapeutic strategies in the regenerative and aesthetic medical fields. This study evaluated the clinical efficacy and safety of adipose tissue stem cell-derived exosomes as an adjuvant therapy after application of fractional CO2 laser for acne scars. A 12-week prospective, double-blind, randomized, split-face trial was performed. A total of 25 patients received 3 consecutive treatment sessions of fractional CO2 laser to the whole face, with a follow-up evaluation. Post-laser treatment regimens were applied; for each patient, one side of the face was treated with adipose tissue stem cell-derived exosomes gel and the other side was treated with control gel. Adipose tissue stem cell-derived exosomes-treated sides had achieved a significantly greater improvement than the control sides at the final follow-up visit (percentage reduction in echelle d'evaluation clinique des cicatrices d'acne scores: 32.5 vs 19.9%, p < 0.01). Treatment-related erythema was milder, and post-treatment downtime was shorter on the applications of human adipose tissue stem cell-derived exosomes-treated side. In conclusion, the combined use of this novel material with resurfacing devices would provide synergistic effects on both the efficacy and safety of atrophic acne scar treatments.
- Published
- 2020
21. Mesenchymal Stem/Stromal Cell-Derived Exosomes for Immunomodulatory Therapeutics and Skin Regeneration
- Author
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Byong Seung Cho, Gyeong Hun Park, Steve Hoseong Yang, Hosung Choi, Junho Lee, Joon Lee, Yong Weon Yi, Dae Hyun Ha, Hyuck Hoon Kwon, Sumi Sung, Jae-Yoon Jung, and Hyun Keun Kim
- Subjects
MSC-exosomes ,Stromal cell ,Review ,Biology ,immunomodulation ,Exosomes ,Exosome ,hair growth ,In vivo ,therapeutics ,Humans ,Immunologic Factors ,Regeneration ,skin barrier ,lcsh:QH301-705.5 ,Skin ,Wound Healing ,mesenchymal stem cells (MSCs) ,Regeneration (biology) ,anti-aging ,Mesenchymal stem cell ,Mesenchymal Stem Cells ,General Medicine ,In vitro ,Microvesicles ,anti-inflammation ,Cell biology ,regenerative aesthetics ,lcsh:Biology (General) ,Wound healing - Abstract
Exosomes are nano-sized vesicles that serve as mediators for cell-to-cell communication. With their unique nucleic acids, proteins, and lipids cargo compositions that reflect the characteristics of producer cells, exosomes can be utilized as cell-free therapeutics. Among exosomes derived from various cellular origins, mesenchymal stem cell-derived exosomes (MSC-exosomes) have gained great attention due to their immunomodulatory and regenerative functions. Indeed, many studies have shown anti-inflammatory, anti-aging and wound healing effects of MSC-exosomes in various in vitro and in vivo models. In addition, recent advances in the field of exosome biology have enabled development of specific guidelines and quality control methods, which will ultimately lead to clinical application of exosomes. This review highlights recent studies that investigate therapeutic potential of MSC-exosomes and relevant mode of actions for skin diseases, as well as quality control measures required for development of exosome-derived therapeutics.
- Published
- 2020
22. Exosomes from Human Adipose Tissue-Derived Mesenchymal Stem Cells Promote Epidermal Barrier Repair by Inducing de Novo Synthesis of Ceramides in Atopic Dermatitis
- Author
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Jason M. Meyer, Hyun-keun Kim, Joon Lee, Dae Hyun Ha, Hyuck Hoon Kwon, Kyong-Oh Shin, Debra Crumrine, Jin Ock Kim, Kyungho Park, Byong Seung Cho, Junho Lee, Yong Weon Yi, Jihye Lim, Sung Eun Kim, Bogyeong Kim, Sejeong Park, Yerin Lee, Joan S. Wakefield, Peter M. Elias, and Gyeong-Hun Park
- Subjects
restoration ,medicine.medical_treatment ,Stratum granulosum ,Adipose tissue ,Dermatitis ,Lamellar granule ,Ceramides ,Regenerative Medicine ,Exosomes ,Atopic ,Article ,Proinflammatory cytokine ,Dermatitis, Atopic ,Mice ,Stem Cell Research - Nonembryonic - Human ,medicine ,Stratum corneum ,Genetics ,2.1 Biological and endogenous factors ,Animals ,Humans ,skin barrier ,Aetiology ,lcsh:QH301-705.5 ,Skin ,lamella body ,ASC-exosomes ,ceramides ,integumentary system ,atopic dermatitis ,Chemistry ,Mesenchymal stem cell ,Lipid metabolism ,Mesenchymal Stem Cells ,General Medicine ,Stem Cell Research ,anti-inflammation ,Cell biology ,Cytokine ,medicine.anatomical_structure ,lcsh:Biology (General) ,Adipose Tissue ,Stem Cell Research - Nonembryonic - Non-Human ,Female ,Epidermis - Abstract
Atopic dermatitis (AD) is a multifactorial, heterogeneous disease associated with epidermal barrier disruption and intense systemic inflammation. Previously, we showed that exosomes derived from human adipose tissue-derived mesenchymal stem cells (ASC-exosomes) attenuate AD-like symptoms by reducing multiple inflammatory cytokine levels. Here, we investigated ASC-exosomes&rsquo, effects on skin barrier restoration by analyzing protein and lipid contents. We found that subcutaneous injection of ASC-exosomes in an oxazolone-induced dermatitis model remarkably reduced trans-epidermal water loss, while enhancing stratum corneum (SC) hydration and markedly decreasing the levels of inflammatory cytokines such as IL-4, IL-5, IL-13, TNF-&alpha, IFN-&gamma, IL-17, and TSLP, all in a dose-dependent manner. Interestingly, ASC-exosomes induced the production of ceramides and dihydroceramides. Electron microscopic analysis revealed enhanced epidermal lamellar bodies and formation of lamellar layer at the interface of the SC and stratum granulosum with ASC-exosomes treatment. Deep RNA sequencing analysis of skin lesions demonstrated that ASC-exosomes restores the expression of genes involved in skin barrier, lipid metabolism, cell cycle, and inflammatory response in the diseased area. Collectively, our results suggest that ASC-exosomes effectively restore epidermal barrier functions in AD by facilitating the de novo synthesis of ceramides, resulting in a promising cell-free therapeutic option for treating AD.
- Published
- 2020
23. Impact Angle Control with Time Varying Continuous Biased PNG for Non-maneuvering Target
- Author
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Sang-Hyuck Park, Jang-Seong Park, Hyuck-Hoon Kwon, Bong-Gyun Park, and Yoon-Young Kim
- Subjects
Control theory ,Impact angle ,Control (management) ,Mathematics - Published
- 2018
24. Toxicological evaluation of exosomes derived from human adipose tissue-derived mesenchymal stem/stromal cells
- Author
-
Joon Lee, Jieun Kim, Sang Hee Lee, Jihye Lim, Gyeong Hun Park, Dae Hyun Ha, Hyuck Hoon Kwon, Steve Hoseong Yang, Byong Seung Cho, Jae-Yoon Jung, Sun Don Kim, Sang Rae Park, Hyun Kul Lee, Jun Ho Lee, Yong Weon Yi, and Jinkwon Youn
- Subjects
Stromal cell ,BALB 3T3 Cells ,Adipose tissue ,010501 environmental sciences ,Pharmacology ,Toxicology ,Administration, Cutaneous ,Exosomes ,Eye ,030226 pharmacology & pharmacy ,01 natural sciences ,Rats, Sprague-Dawley ,03 medical and health sciences ,Paracrine signalling ,Mice ,0302 clinical medicine ,Toxicity Tests ,Medicine ,Animals ,Humans ,0105 earth and related environmental sciences ,Skin ,business.industry ,Mesenchymal stem cell ,Mesenchymal Stem Cells ,General Medicine ,Microvesicles ,RAW 264.7 Cells ,Mechanism of action ,Toxicity ,Female ,medicine.symptom ,Phototoxicity ,business - Abstract
Several studies report that the therapeutic mechanism of action of mesenchymal stem/stromal cells (MSCs) is mainly mediated by paracrine factors that are released from MSCs such as exosomes. Exosomes are nano-sized extracellular vesicles that are transferred to target cells for cell-to-cell communication. Although MSC-derived exosomes (MSC-exosomes) are suggested as novel cell-free therapeutics for various human diseases, evaluation studies for the safety and toxicity of MSC-exosomes are limited. The purpose of our study was to evaluate the toxicological profile, including skin sensitization, photosensitization, eye and skin irritation, and acute oral toxicity using exosomes derived from human adipose tissue-derived MSCs (ASC-exosomes) in accordance with the OECD guidelines and the principles of Good Laboratory Practice. The ASC-exosomes were classified as a potential non-sensitizer in the skin sensitization test, UN GHS no category in the eye irritation test, and as a skin non-irritant in the skin irritation test, and did not induce any toxicity in the phototoxicity test or in acute oral toxicity testing. Our findings are the first to suggest that ASC-exosomes are safe for use as a topical treatment, with no adverse effects in toxicological testing, and have potential application as a therapeutic agent, cosmetic ingredient, or for other biological uses.
- Published
- 2019
25. Expression of inflammatory and fibrogenetic markers in acne hypertrophic scar formation: focusing on role of TGF-β and IGF-1R
- Author
-
Jungyoon Moon, Ji Young Yoon, Ji Hoon Yang, Hyuck Hoon Kwon, Dae Hun Suh, and Seonguk Min
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Cicatrix, Hypertrophic ,Scars ,Apoptosis ,Vimentin ,Smad2 Protein ,Dermatology ,Receptor, IGF Type 1 ,Transforming Growth Factor beta1 ,Pathogenesis ,Young Adult ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Hypertrophic scar ,Transforming Growth Factor beta3 ,0302 clinical medicine ,Acne Vulgaris ,medicine ,Humans ,Acne ,Skin ,Smad4 Protein ,medicine.diagnostic_test ,biology ,business.industry ,Receptors, Somatomedin ,General Medicine ,medicine.disease ,Real-time polymerase chain reaction ,Case-Control Studies ,030220 oncology & carcinogenesis ,Skin biopsy ,biology.protein ,Immunohistochemistry ,Female ,medicine.symptom ,business ,Signal Transduction - Abstract
Acne vulgaris is a universal skin disease and it may leave a scar when the original skin lesion disappears. These scars can cause cosmetic problems and psychological burden, leading to poor quality of life of patients. Acne scars are classified into atrophic scars and hypertrophic scars. As most of the acne scars are atrophic, many studies have been conducted focusing on the treatment of atrophic lesions. This study was conducted to investigate the underlying pathogenesis of acne hypertrophic scars by identifying roles of fibrogenetic and inflammatory markers. Skin biopsy samples were obtained from hypertrophic scars of face and back and from adjacent normal tissues as control group. Some samples from back were immature hypertrophic scars and the other samples were in mature stages. Immunohistochemistry staining and quantitative PCR were performed for fibrogenetic and inflammatory markers. Both in mature and immature hypertrophic scars, vimentin and α-SMA were increased. Production of TGF-β3 protein as well as transcription of TGF-β3 was also significantly elevated. In contrast, expression of TGF-β1 showed no increase. Instead, expression levels of SMAD2 and SMAD4 were increased. Elevations of CD45RO, TNF-α and IL-4 and reduction of IL-10 were observed. In immature hypertrophic scars, IGF-1R and insulin-degrading enzyme expression were increased. Increased apoptosis was observed in immature stages of hypertrophic scars but not in mature stages. Elevations of TGF-β3, SMAD2 and SMAD4 in hypertrophic scars and increase of IGF-1R in immature stages may give some clues for acne hypertrophic scar formation.
- Published
- 2018
26. Sum-of-Squares-Based Region of Attraction Analysis for Gain-Scheduled Three-Loop Autopilot
- Author
-
Min-Won Seo, Han-Lim Choi, and Hyuck-Hoon Kwon
- Subjects
0209 industrial biotechnology ,Polynomial ,Computer science ,020208 electrical & electronic engineering ,Linear system ,Explained sum of squares ,Aerospace Engineering ,02 engineering and technology ,law.invention ,Nonlinear system ,020901 industrial engineering & automation ,Missile ,Control and Systems Engineering ,law ,Control theory ,Autopilot ,Convex optimization ,0202 electrical engineering, electronic engineering, information engineering ,General Materials Science ,Electrical and Electronic Engineering - Abstract
A conventional method of designing a missile autopilot is to linearize the original nonlinear dynamics at several trim points, then to determine linear controllers for each linearized model, and finally implement gain-scheduling technique. The validation of such a controller is often based on linear system analysis for the linear closed-loop system at the trim conditions. Although this type of gain-scheduled linear autopilot works well in practice, validation based solely on linear analysis may not be sufficient to fully characterize the closed-loop system especially when the aerodynamic coefficients exhibit substantial nonlinearity with respect to the flight condition. The purpose of this paper is to present a methodology for analyzing the stability of a gain-scheduled controller in a setting close to the original nonlinear setting. The method is based on sum-of-squares (SOS) optimization that can be used to characterize the region of attraction of a polynomial system by solving convex optimization problems. The applicability of the proposed SOS-based methodology is verified on a short-period autopilot of a skid-to-turn missile.
- Published
- 2018
27. Combination of platelet rich plasma in fractional carbon dioxide laser treatment increased clinical efficacy of for acne scar by enhancement of collagen production and modulation of laser-induced inflammation
- Author
-
Hyuck Hoon Kwon, Seon Yong Park, Seonguk Min, Ji Young Yoon, Dae Hun Suh, and Jungyoon Moon
- Subjects
Erythema ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Inflammation ,Dermatology ,Pharmacology ,Carbon dioxide laser ,medicine.disease ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Collagen, type I, alpha 1 ,0302 clinical medicine ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Platelet-rich plasma ,Skin biopsy ,Medicine ,Surgery ,medicine.symptom ,business ,Fibroblast ,Acne - Abstract
Background Platelet-rich plasma (PRP) which contains large amounts of growth factors has been tried to enhance therapeutic efficacy of laser treatment for acne scar with unknown underlying mechanism. Objectives The present study was conducted to investigate the molecular mechanism of increased clinical efficacy of PRP when combined with fractional laser treatment for treating acne scars. Methods Subjects with mild to moderate acne scars were treated with two sessions of fractional CO2 laser therapy given with and without co-administration of PRP. Skin biopsy specimens were obtained at baseline, 1, 3, 7, and 28 days for investigation of molecular profiles associated with skin changes produced by laser plus PRP treatment. Results The PRP treatment increased clinical efficacy with decreased severity of adverse effects such as erythema, swelling and oozing. Productions of TGFβ1 and TGFβ3 proteins were more highly elevated on the PRP-treated side of the face compared to the control side at day 28. Furthermore, PRP-treated side showed significant increase of c-myc, TIMP, and HGF expression. Experimental fibroblast culture model was also used. PRP administration after laser irradiation increased expressions of p-Akt, TGFβ1, TGFβ3, β-catenin, collagen 1, and collagen 3 in both dose-dependent and time dependent manners in fibroblast. Moreover, we acquired clinical and histological data through randomized control clinical trial. Conclusion Taken together with human study results combined with the data from cell experiments we suggest that PRP treatment increased fibrogenetic molecules induced by fractional CO2 laser, which have association with clinical effect. Lasers Surg. Med. 50:302-310, 2018. © 2017 Wiley Periodicals, Inc.
- Published
- 2017
28. A novel combination regimen with intense focused ultrasound and pressure- and dose-controlled transcutaneous pneumatic injection of hypertonic glucose solution for lifting and tightening of the aging face
- Author
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Hyuck Hoon Kwon, Jae-Yoon Jung, Sun Chul Choi, and Kyung-Hoon Park
- Subjects
Adult ,medicine.medical_specialty ,Time Factors ,Ultrasonic Therapy ,Cosmetic Techniques ,Dermatology ,Aging face ,Focused ultrasound ,Injections ,Facial contour ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Glucose Solution, Hypertonic ,medicine ,Humans ,Rejuvenation ,030223 otorhinolaryngology ,Adverse effect ,Beneficial effects ,Aged ,Skin ,business.industry ,Middle Aged ,Combined Modality Therapy ,Skin Aging ,Surgery ,Regimen ,Patient Satisfaction ,Face ,Female ,Collagen ,business ,Hypertonic glucose solution - Abstract
SummaryBackground Intense focused ultrasound (IFUS) has demonstrated moderate efficacy for facial laxity of the aging face. Pressure- and dose-controlled transcutaneous pneumatic injections of hypertonic glucose solution (TPIG) are a minimally invasive way to deliver solution into the skin for therapeutic purposes. Recently, its application around temporal areas is known to exert early-onset lifting effects with facial contour rejuvenation. Aims We sought to evaluate the safety and efficacy of this novel combination regimen with IFUS and TPIG for lifting and tightening of aging face. Patients and Methods Twenty-two Korean subjects with mild-to-moderate facial skin laxity were evaluated after receiving a sequential single session of IFUS and TPIG treatments. Dermatologists’ objective assessments for general appearance, and mid- and low faces based on photographic images were performed at 1- and 12-week post-treatment follow-ups. Patients’ subjective assessments were also conducted. Skin biopsies were taken at baseline and the last visit. Results Among 22 subjects, twenty (91%) demonstrated improvement after 12-week follow-up. We also observed similarly improved state just after 1 week of treatments (82%: 18/22). Specifically, improvement of the mid-face was evident from the first week, while the progress of the low face improvement was observed at the twelve week. Subjective assessments paralleled these findings. No seriously adverse effect was observed during procedures. Histologic evaluation showed greater dermal collagen fibers throughout the dermis after treatments. Conclusion Combination treatment with IFUS and TPIG has beneficial effects for skin lifting and tightening with early-onset time.
- Published
- 2017
29. Histologic analyses on the response of the skin to 1,927-nm fractional thulium fiber laser treatment
- Author
-
Un-Cheol Yeo, Gyeong-Hun Park, Jin Yong Lee, In Ho Kwon, Young Hee Choi, Youin Bae, and Hyuck Hoon Kwon
- Subjects
Swine ,business.industry ,Fractional laser ,chemistry.chemical_element ,Dermis ,Dermatology ,01 natural sciences ,010309 optics ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Thulium ,Optics ,chemistry ,Fiber laser ,0103 physical sciences ,Animals ,Medicine ,Female ,Surgery ,Laser Therapy ,Epidermis ,business - Abstract
The histologic responses to varied parameters of 1,927-nm fractional thulium fiber laser treatment have not yet been sufficiently elucidated.This study sought to evaluate histologic changes immediately after 1,927-nm fractional thulium fiber laser session at various parameters.The dorsal skin of Yucatan mini-pig was treated with 1,927-nm fractional thulium fiber laser at varied parameters, with or without skin drying. The immediate histologic changes were evaluated to determine the effects of varying laser parameters on the width and the depth of treated zones.The increase in the level of pulse energy widened the area of epidermal changes in the low power level, but increased the dermal penetration depth in the high power level. As the pulse energy level increased, the increase in the power level under the given pulse energy level more evidently made dermal penetration deeper and the treatment area smaller. Skin drying did not show significant effects on epidermal changes, but evidently increased the depth of dermal denaturation under both high and low levels of pulse energy.These results may provide important information to establish treatment parameters of the 1,927-nm fractional thulium fiber laser for various skin conditions.
- Published
- 2017
30. Combined Fractional Treatment of Acne Scars Involving Non-ablative 1,550-nm Erbium-glass Laser and Micro-needling Radiofrequency: A 16-week Prospective, Randomized Split-face Study
- Author
-
Jae Yoon Jung, Sun Chul Choi, Hae Young Park, Hyuck Hoon Kwon, Chanhee Kang, Youin Bae, and Gyeong-Hun Park
- Subjects
Adult ,Male ,inorganic chemicals ,Time Factors ,Seoul ,Cosmetic Techniques ,Lasers, Solid-State ,Dermatology ,law.invention ,Cicatrix ,Young Adult ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Glass laser ,radiofrequency ,0302 clinical medicine ,Randomized controlled trial ,law ,Acne Vulgaris ,Photography ,Humans ,Medicine ,Combined Modality Therapy ,Non ablative ,Prospective Studies ,Low-Level Light Therapy ,Prospective cohort study ,Acne scars ,Dry needling ,business.industry ,acnescar ,technology, industry, and agriculture ,lasersurgery ,General Medicine ,body regions ,Regimen ,Treatment Outcome ,Needles ,RL1-803 ,030220 oncology & carcinogenesis ,fractionalphotothermolysis ,Female ,business ,Nuclear medicine - Abstract
An optimized therapeutic regimen involving a non-ablative fractionated laser or radiofrequency therapy for acne scars has not yet been established. To evaluate whether the combination of a non-ablative fractional laser (NAF) and fractional micro-needling radiofrequency (FMR) has clinical advantages for the treatment of atrophic acne scars compared with NAF alone, a 16-week prospective, randomized split-face study was performed. Each facial side of a patient was treated with 3 sessions of either NAF with FMR or NAF alone, with a 4-week interval between each session. Although both sides demonstrated significant decreases in the échelle d’évaluation clinique des cicatrices d’acné (ECCA) score, the facial side treated using the combination regimen demonstrated greater improvement in ECCA score regarding degree and onset time than the NAF-treated side. Histopathological and immunohistochemical results confirmed the clinical findings. This study demonstrated that a combination regimen involving NAF and FMR could be a viable option with satisfactory efficacy.
- Published
- 2017
31. Stability Analysis of Three-Loop Autopilot with respect to IMU Position and C.G Variation Rate in Guided Missiles
- Author
-
Hyuck-Hoon Kwon, Bong-Gyun Park, and Yoon-Hwan Kim
- Subjects
Loop (topology) ,Inertial measurement unit ,law ,Position (vector) ,Control theory ,Autopilot ,Variation (astronomy) ,Stability (probability) ,Mathematics ,law.invention - Published
- 2016
32. Composite Guidance Scheme for Impact Angle Control Against a Nonmaneuvering Moving Target
- Author
-
Tae-Hun Kim, Bong-Gyun Park, Hyuck-Hoon Kwon, and Yoon-Hwan Kim
- Subjects
020301 aerospace & aeronautics ,0209 industrial biotechnology ,Computer science ,Angle of attack ,Applied Mathematics ,Aerospace Engineering ,02 engineering and technology ,Optimal control ,law.invention ,Acceleration ,020901 industrial engineering & automation ,Missile ,0203 mechanical engineering ,Space and Planetary Science ,Control and Systems Engineering ,law ,Control theory ,Autopilot ,Trajectory ,Proportional navigation ,Limit (mathematics) ,Electrical and Electronic Engineering - Abstract
I N ADVANCED guidance law designs, impact angle control has been widely required to maximize the effect of thewarhead and to achieve a high kill probability. Since the first paper for impact angle control [1] was published, to the best of our knowledge, many guidance laws with impact angle constraint have been studied. Ryoo et al. [2] proposed a pure energy optimal guidance law with impact angle constraint. As an extension of this work, Ryoo et al. [3] proposed an optimal impact angle control guidance law minimizing the time-to-go weighted energy cost function. Lu et al. [4] developed three-dimensional guidance laws, which were based on proportional navigation (PN) with adaptive guidance parameters, to achieve impact angle requirements. Ratnoo and Ghose proposed a two-phase guidance law for capturing all possible impact angles against a stationary target [5] and a nonstationary nonmaneuvering target [6]. The proposed guidance law used PN with N < 2 for the initial phase to cover impact angles from zero to −π through an orientation trajectory and PNwithN ≥ 2 for the final phase to intercept the target with the desired impact angle. Erer andMerttopcuoglu [7] proposed a similar two-phase guidance law switching from biased PN to PN when the integral value of the bias met a certain value determined by engagement conditions. Most of research mentioned has focused on the impact angle as well as a zero terminal miss distance. The impact angle control, however, made the missile trajectory highly curved, which might have then missed the target within the seeker’s lookangle limit. Since this leads to the mission failure, it is very important to consider the missile’s physical constraints, such as the seeker’s look-angle and maximum acceleration limits. Recently, studies considering the look-angle limits as well as the impact angle have been carried out. Park et al. [8] proposed a composite guidance law comprising PN with N 1 to maintain the constant look angle and PNwithN ≥ 2 to intercept the target with the desired impact angle. In [9], the error feedback loop of the look angle was included in PN with N 1 for robustness and converging from the arbitrary look angle to the desired one. In [10], a pure energy optimal guidance lawwith an impact angle constraint and the seeker’s look-angle limit was developed using optimal control theory with state variable inequality constraint. Kim et al. [11] proposed a biasshaping method, based on the work in [7], to consider the look-angle and acceleration limits. Tekin and Erer [12] presented a two-phase guidance law with a numerical process for calculating navigation gains to handle the look-angle limits and acceleration constraints. Also, Erer et al. [13] proposed another two-phase guidance scheme to address the look-angle constraint problem, which can select an initial phase guidance lawbetween PNandbiasedPN.Ratnoo [14] dealt with a similar problem to [8] and showed analytic guarantees for achieving all impact angles with any finite field-of-view (FOV) limit. These works have been studied against stationary targets, so the impact angle errors may appear at the instant of interception if the guidance laws presented in [8–14] are applied to the case of moving targets. In this Note, a composite guidance scheme, studied in [8,9], is extended to the case of a nonmaneuvering moving target. The proposed guidance scheme is composed of modified deviated pure pursuit (DPP) with the error feedback loop of the look angle for the initial guidance phase and PN with N ≥ 3 for the final guidance phase: the first phase is to maintain the constant look angle of the seeker, and the second is to intercept themoving targetwith a terminal angle constraint. The switching of guidance phases occurs when satisfying a specific line-of-sight (LOS) angle determined by engagement conditions. Guidelines on the gain tuning of modified DPP and calculation of themaximumachievable impact angle, which is calculated by taking into account the seeker’s look-angle and maximum acceleration limits, are also investigated for guidance designers.
- Published
- 2016
33. Fractional Microneedling Radiofrequency Treatment for Acne-related Post-inflammatory Erythema
- Author
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Ji Young Yoon, Dae Hun Suh, Seon Yong Park, Hyuck Hoon Kwon, and Seonguk Min
- Subjects
Male ,Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,Time Factors ,Erythema ,Radio Waves ,medicine.drug_class ,Biopsy ,Antibiotics ,Dermatology ,acne ,post-inflammatory erythema ,fractional microneedlingradiofrequency ,Young Adult ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Acne Vulgaris ,medicine ,Humans ,skin and connective tissue diseases ,Adverse effect ,Acne ,Retrospective Studies ,Skin ,integumentary system ,medicine.diagnostic_test ,business.industry ,Interleukin-8 ,NF-kappa B ,Retrospective cohort study ,Equipment Design ,General Medicine ,medicine.disease ,Immunohistochemistry ,Pulsed Radiofrequency Treatment ,Surgery ,Treatment Outcome ,Needles ,Patient Satisfaction ,030220 oncology & carcinogenesis ,Skin biopsy ,Female ,Inflammation Mediators ,medicine.symptom ,business - Abstract
Post-inflammatory erythema is a common result of acne inflammation and is cosmetically unacceptable without effective treatment. Fractional microneedling radiofrequency (FMR) has potential for treatment of post-inflammatory erythema. The aim of this study was to evaluate the efficacy and safety of this treatment. A retrospective chart review was undertaken of 25 patients treated with 2 sessions of radiofrequency at 4-week intervals and 27 patients treated with oral antibiotics and/or topical agents. Efficacy was assessed through an investigator's global assessment of photographs, and the analysis of erythema with image analysis software and photometric devices. Histological changes resulting from the treatment were evaluated by skin biopsy. FMR treatment resulted in significant improvements in erythema with no severe adverse effects. Histological study revealed a reduction in vascular markers and inflammation. FMR is a safe and effective treatment for post-inflammatory erythema, with potential anti-inflammatory and anti-angiogenetic properties.
- Published
- 2016
34. Combined treatment of melasma involving low-fluence Q-switched Nd:YAG laser and fractional microneedling radiofrequency
- Author
-
Sun Chul Choi, Gyeong-Hun Park, Jae-Yoon Jung, and Hyuck Hoon Kwon
- Subjects
Adult ,Male ,Melasma ,Dermatology ,Lasers, Solid-State ,Melanosis ,law.invention ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Combined treatment ,Asian People ,law ,Medicine ,Humans ,Retrospective Studies ,030203 arthritis & rheumatology ,Low fluence ,business.industry ,Middle Aged ,medicine.disease ,Laser ,Radiofrequency Therapy ,Combined Modality Therapy ,Regimen ,Treatment Outcome ,Nd:YAG laser ,Disease Progression ,Female ,business ,Nuclear medicine - Abstract
Background: While low fluence Q-switched Nd:YAG laser (QSNY) demonstrates moderate efficacy in the melasma treatment for darker skin types, this single regimen still remains challenges. Fractional ...
- Published
- 2018
35. Comparison of novel dual mode vs conventional single pass of a 1450-nm diode laser in the treatment of acne vulgaris for Korean patients: A 20-week prospective, randomized, split-face study
- Author
-
Jae Yoon Jung, Gyeong-Hun Park, Sun Chul Choi, Youin Bae, and Hyuck Hoon Kwon
- Subjects
Laser surgery ,Sebum secretion ,Adult ,Male ,Single pass ,medicine.medical_specialty ,Combination therapy ,Adolescent ,medicine.medical_treatment ,Pain ,Dermatology ,Severity of Illness Index ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Acne Vulgaris ,Republic of Korea ,medicine ,Humans ,Prospective Studies ,Acne ,business.industry ,Dual mode ,medicine.disease ,Hyperpigmentation ,Dermatitis, Seborrheic ,Sebum ,Regimen ,Treatment Outcome ,030220 oncology & carcinogenesis ,Female ,Laser Therapy ,medicine.symptom ,Lasers, Semiconductor ,business ,Facial Dermatoses - Abstract
Background Although a 1450-nm diode laser has been shown to be effective for acne, the conventional high-energy stamp-only regimen is often associated with pain and hyperpigmentation, especially for dark-skinned individuals. Aims To evaluate whether the novel dual regimen has clinical advantages for acne treatments compared with conventional regimen in Asian patients. Patients and methods Twenty-four Korean patients with facial acne were treated with a 1450-nm diode laser through a 20-week, randomized, split-face study. The patients were treated with three consecutive sessions at 4-week intervals. One half of the face received a dual regimen consisting of low-fluence stamping mode (5-6 J/cm2 ) for inflammatory acne lesions only, followed by 4-5 passes of moving mode for the full face. The other side received a single-pass treatment of conventional high-fluence stamp mode (14-15 J/cm2 ). Evaluations for acne, sebum secretion measurements, and safety profiles were performed. Results At the final 12-week follow-up evaluations, the dual-mode side demonstrated better improvements in both inflammatory and noninflammatory lesion counts, acne severity assessments, and reduction in sebum secretion compared with stamp-only side. Subjective satisfaction for the improvement for acne, seborrhea, and texture correlated well with objective assessments. In addition, degrees of pain and treatment-related side effects were remarkably decreased in the novel dual mode. Conclusion This novel dual regimen of the 1450-nm laser demonstrated improved efficacies for acne and seborrhea with satisfactory safety profiles. Therefore, this regimen would be a viable option for acne treatments either as monotherapy or as combination therapy.
- Published
- 2018
36. Combined treatment for skin laxity of the aging face with monopolar radiofrequency and intense focused ultrasound in Korean subjects
- Author
-
Hyuck Hoon Kwon, Won-Yong Lee, Gyeong-Hun Park, Jae Yoon Jung, Sun Chul Choi, and Youin Bae
- Subjects
Adult ,Radio Waves ,Ultrasonic Therapy ,Dentistry ,Dermatology ,Aging face ,Cosmetic Techniques ,Focused ultrasound ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Combined treatment ,Asian People ,Republic of Korea ,Medicine ,Humans ,Rejuvenation ,030223 otorhinolaryngology ,Aged ,business.industry ,Middle Aged ,Radiofrequency Therapy ,Combined Modality Therapy ,Skin Aging ,Patient Satisfaction ,Face ,Skin laxity ,Surgery ,Female ,business - Abstract
Although various minimal invasive approaches are available for aging skin laxity, they alone may not lead to notably satisfactory results.To evaluate the effectiveness and safety of combination regimen with monopolar radiofrequency (MRF) and intense-focused ultrasound (IFUS) in facial lifting and tightening.Twenty-two Korean participants with aging face received a sequential single session of MRF and IFUS treatment. Objective and subjective assessments for improvement were performed at the 20-week post-treatment. Safety profiles were also recorded, and skin biopsies were taken at baseline and follow-up visit.Based on the objective assessment for the overall facial skin tightening and laxity, 19 patients (90%) demonstrated "moderate" or better improvements (more than 25%) compared with baseline. Specifically, improvements of skin laxity and sagging, and droopy jaw line were more noticeable compared with that of superficial skin texture (P 0.05). Subjective satisfactions were generally consistent with objective findings, and no serious adverse effect was observed. Histologic evaluation showed increased dermal collagen fibers throughout the dermis after treatments (P 0.05).Combination treatment of MRF and IFUS has cumulative benefits for skin lifting and tightening with satisfactory safety profiles in Asian subjects.
- Published
- 2018
37. Combination of platelet rich plasma in fractional carbon dioxide laser treatment increased clinical efficacy of for acne scar by enhancement of collagen production and modulation of laser-induced inflammation
- Author
-
Seonguk, Min, Ji Young, Yoon, Seon Yong, Park, Jungyoon, Moon, Hyuck Hoon, Kwon, and Dae Hun, Suh
- Subjects
Adult ,Male ,Esthetics ,Platelet-Rich Plasma ,Biopsy, Needle ,Combined Modality Therapy ,Immunohistochemistry ,Severity of Illness Index ,Statistics, Nonparametric ,Cicatrix ,Young Adult ,Treatment Outcome ,Reference Values ,Acne Vulgaris ,Lasers, Gas ,Humans ,Female ,Single-Blind Method ,Collagen ,Prospective Studies ,Low-Level Light Therapy ,Facial Dermatoses ,Follow-Up Studies - Abstract
Platelet-rich plasma (PRP) which contains large amounts of growth factors has been tried to enhance therapeutic efficacy of laser treatment for acne scar with unknown underlying mechanism.The present study was conducted to investigate the molecular mechanism of increased clinical efficacy of PRP when combined with fractional laser treatment for treating acne scars.Subjects with mild to moderate acne scars were treated with two sessions of fractional COThe PRP treatment increased clinical efficacy with decreased severity of adverse effects such as erythema, swelling and oozing. Productions of TGFβ1 and TGFβ3 proteins were more highly elevated on the PRP-treated side of the face compared to the control side at day 28. Furthermore, PRP-treated side showed significant increase of c-myc, TIMP, and HGF expression. Experimental fibroblast culture model was also used. PRP administration after laser irradiation increased expressions of p-Akt, TGFβ1, TGFβ3, β-catenin, collagen 1, and collagen 3 in both dose-dependent and time dependent manners in fibroblast. Moreover, we acquired clinical and histological data through randomized control clinical trial.Taken together with human study results combined with the data from cell experiments we suggest that PRP treatment increased fibrogenetic molecules induced by fractional CO
- Published
- 2017
38. Cross-sectional survey of awareness and behavioral pattern regarding acne and acne scar based on smartphone application
- Author
-
Dae Hun Suh, Jee Bum Lee, Seonguk Min, Hyuck Hoon Kwon, Sang Joo Lee, Young Suck Ro, Hyo Hyun Ahn, Mi Youn Park, Kwang Joong Kim, Mi Woo Lee, Myeung Nam Kim, Weon Ju Lee, Seon Yong Park, Hoon Kang, Nack In Kim, and Kyu Joong Ahn
- Subjects
Adult ,Male ,Health Knowledge, Attitudes, Practice ,medicine.medical_specialty ,Time Factors ,Adolescent ,Office Visits ,Cross-sectional study ,Emotions ,Dermatology ,Time-to-Treatment ,Cicatrix ,Young Adult ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Patient satisfaction ,Surveys and Questionnaires ,Acne Vulgaris ,medicine ,Humans ,030212 general & internal medicine ,Age of Onset ,Young adult ,Child ,Acne ,business.industry ,Behavioral pattern ,Sequela ,Social Participation ,medicine.disease ,Mobile Applications ,Self Care ,Cross-Sectional Studies ,Patient Satisfaction ,Disease Progression ,Female ,Dermatologic Agents ,Smartphone ,Age of onset ,business ,Psychosocial - Abstract
Background Although acne scar is a permanent sequela that may be induced by improper management of active acne lesion, patient behavior patterns and awareness regarding acne are unclear. The aim of this study was to identify awareness and behavioral patterns concerning acne and acne scar of people having acne and differences between those with and without acne scars. Methods The survey was performed via smartphone application for 900 participants in their second to fourth decade having current or previous acne lesions. They were further categorized into two groups based on the presence of acne scar (scar and scarless groups) with no statistical difference in demographic composition. Results The mean age of all participants was 24.6 ± 5.3. The scar group had a longer disease duration (4.9 years) than those of the scarless group (2.2 years). Participants in the scar group thought that acne scarring affected psychosocial aspects more negatively compared with those in the scarless group. Participants in the scarless group visited dermatology clinics earlier than those in the scar group. In the scar group, 62.1% of participants have never had their acne scars treated medically. Most (88.6%) participants from both groups believed that non-dermatologic treatment caused side effects or aggravated their acne. Conclusions Participants with acne scars tended to treat their acne and acne scars improperly, which could negatively affect their daily lives. Acne scars are sequelae of acne and should be regarded as a distinct disease entity, requiring a patient's early visit to dermatologic clinics.
- Published
- 2015
39. Do tutorials on application method enhance adapalene-benzoyl peroxide combination gel tolerability in the treatment of acne?
- Author
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Hyuck Hoon Kwon, Dae Hun Suh, Seonguk Min, Ji Young Yoon, and Seon Yong Park
- Subjects
Adult ,Male ,medicine.medical_specialty ,Combination therapy ,Adapalene/benzoyl peroxide ,Dermatology ,Benzoyl peroxide ,Lesion ,Young Adult ,Asian People ,Patient Education as Topic ,Adapalene ,Adapalene, Benzoyl Peroxide Drug Combination ,Acne Vulgaris ,Republic of Korea ,medicine ,Humans ,Single-Blind Method ,Application methods ,Acne ,business.industry ,General Medicine ,medicine.disease ,Treatment Outcome ,Tolerability ,Female ,Dermatologic Agents ,medicine.symptom ,business ,Gels ,medicine.drug - Abstract
Fixed-dose combination adapalene 0.1% and benzoyl peroxide 2.5% gel (A-BPO) has rarely been studied for Asian acne patients, while they have complained of local irritations more often when applying individual components. In this study, we compared A-BPO gel with benzoyl peroxide (BPO) in terms of efficacy and tolerability in Korean patients first, and assessed the clinical benefit of a dermatological tutorial on application technique in reducing irritations for A-BPO. This study was conducted as a single-blind controlled split-face trial for a 12-week period. Each half facial side of 85 patients was randomly assigned to either A-BPO or BPO. Success rate, lesion counts and safety profiles were evaluated (analysis I). During initial assignment, all patients were further randomized to either dermatological tutorial (DT) or non-tutorial (NT) subgroups depending on the presence of dermatologists' tutorials for application methods to their A-BPO sides. Clinical data of the A-BPO side was compared between two subgroups (analysis II). As a result, A-BPO gel outperformed BPO, demonstrating better efficacy in success rates and lesion counts as early as 1 week. However, A-BPO proved significantly less tolerable compared with both BPO and previous A-BPO data from Caucasians. Bioengineering measurements further confirmed clinical data (analysis I). The DT subgroup achieved much better tolerability with comparable therapeutic efficacies compared with the NT subgroup (analysis II). In conclusion, A-BPO demonstrated higher efficacies in acne compared with BPO in Korean patients, while skin irritation levels were notable concurrently. Dermatologists' education for application methods would significantly decrease these side-effects, maintaining superior efficacy levels.
- Published
- 2015
40. Composite Guidance Law for Impact Angle Control Against Moving Targets Under Physical Constraints
- Author
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Tae-Hun Kim, Hyuck-Hoon Kwon, Youn-Hwan Kim, and Bong-Gyun Park
- Subjects
Computer science ,Control theory ,Control (management) ,Composite number ,Impact angle - Published
- 2015
41. Combination Treatment with Human Adipose Tissue Stem Cellderived Exosomes and Fractional CO2 Laser for Acne Scars: A 12-week Prospective, Double-blind, Randomized, Split-face Study.
- Author
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Hyuck Hoon KWON, YANG, Steven Hoseong, LEE, Joon, PARK, Byung Cheol, PARK, Kui Young, Jae Yoon JUNG, Youin BAE, and PARK, Gyeong-Hun
- Subjects
ADIPOSE tissues ,CARBON dioxide ,EXOSOMES ,SCARS ,CHEMICAL peel ,ACNE - Abstract
A variety of applications of human adipose tissue stem cell-derived exosomes have been suggested as novel cell-free therapeutic strategies in the regenerative and aesthetic medical fields. This study evaluated the clinical efficacy and safety of adipose tissue stem cell- derived exosomes as an adjuvant therapy after application of fractional CO2 laser for acne scars. A 12-week prospective, double-blind, randomized, split-face trial was performed. A total of 25 patients received three consecutive treatment sessions of fractional CO2 laser to the whole face, with a follow-up evaluation. Postlaser treatment regimens were applied; for each patient, one side of the face was treated with adipose tissue stem cell-derived exosomes gel and the other side was treated with control gel. Adipose tissue stem cell-derived exosomes-treated sides had achieved a significantly greater improvement than the control sides at the final follow-up visit (percentage reduction in échelle d'évaluation clinique des cicatrices d'acné scores: 32.5 vs 19.9%, p < 0.01). Treatment-related erythema was milder, and post-treatment downtime was shorter on the human adipose tissue stem cell-derived exosomes-treated side. In conclusion, the combined use of this novel material with resurfacing devices would provide synergistic effects on both the efficacy and safety of atrophic acne scar treatments. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
42. Analysis of Korean acne patients according to age groups based on two multicenter studies
- Author
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Kwang Joong Kim, Nack In Kim, Young Chul Kye, Kyu Joong Ahn, Mi Woo Lee, Jee Bum Lee, Kui Young Park, Young Suck Ro, Hyo Hyun Ahn, Yu Sung Choi, Seonguk Min, Weon Ju Lee, Margaret Song, Dae Hun Suh, Myeung Nam Kim, Hyuck Hoon Kwon, Mi Youn Park, Hoon Kang, and Kyung Ho Kim
- Subjects
Adult ,Male ,medicine.medical_specialty ,Pediatrics ,Adolescent ,Dermatology ,Young Adult ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Age groups ,030225 pediatrics ,Acne Vulgaris ,Republic of Korea ,Epidemiology ,medicine ,Humans ,Child ,Acne ,Retrospective Studies ,business.industry ,Medical record ,Age Factors ,Infant ,Treatment options ,General Medicine ,medicine.disease ,Child, Preschool ,Female ,business - Abstract
Along with increasing public concerns on acne and its complications, increasing treatment options seem to lead more acne patients to clinics globally, including Korea. The aim of the present study was to investigate the number and distribution of acne patients according to age group by analyzing number and age of outpatients from several general hospitals in Korea. Two retrospective multicenter studies including 14 general hospitals for a maximum of 10 years were conducted by medical chart review of acne patients. During the last 10 years, total acne patients have increased by 60% in number and patients under the age of 19 years have doubled. Adult acne patients (aged >18 years) accounted for the biggest portion in total acne patients at over 80%. Although upper grade of elementary school patients (aged 10–12 years) accounted for the biggest portion among the childhood acne patients, children under 10 years have also increased rapidly by 73% during the last 10 years. Childhood acne patients (aged
- Published
- 2016
43. Linear extensions of hypopigmentation as a side effect of topical corticosteroid application
- Author
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Dae Hun Suh and Hyuck Hoon Kwon
- Subjects
030203 arthritis & rheumatology ,medicine.medical_specialty ,Side effect ,business.industry ,MEDLINE ,Dermatology ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Topical corticosteroid ,medicine ,medicine.symptom ,business ,Hypopigmentation - Published
- 2016
44. Clinical and Histological Evaluations of Enlarged Facial Skin Pores After Low Energy Level Treatments With Fractional Carbon Dioxide Laser in Korean Patients
- Author
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Gyeong-Hun Park, Won-Yong Lee, Hyuck Hoon Kwon, Sun Chul Choi, and Jae-Yoon Jung
- Subjects
Adult ,Male ,medicine.medical_treatment ,Fractional laser ,Dermatology ,Low energy level ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Laser treatments ,0302 clinical medicine ,Asian People ,medicine ,Humans ,In patient ,Prospective Studies ,Low-Level Light Therapy ,Skin pathology ,Skin ,Co2 laser ,business.industry ,General Medicine ,Carbon dioxide laser ,Middle Aged ,Skin Aging ,Facial skin ,030220 oncology & carcinogenesis ,Face ,Lasers, Gas ,Surgery ,Female ,Nuclear medicine ,business - Abstract
Background Enlarged facial pores can be an early manifestation of skin aging and they are a common aesthetic concern for Asians. However, studies of improving the appearance of enlarged pores have been limited. Objective The authors aimed to study the application of CO2 fractional laser treatment in patients with enlarged facial pores. Methods A total of 32 patients with dilated facial pores completed 3 consecutive sessions of low energy level treatments with a fractional CO2 laser at 4-week intervals. Image analysis was performed to calculate the number of enlarged pores before each treatment session and 12 weeks after the final treatment. Results After application of laser treatments, there was a significant decrease in the number of enlarged pores. The mean number of enlarged pores was decreased by 28.8% after the second session and by 54.5% at post-treatment evaluation. Post-treatment side effects were mild and transitory. Histological and immunohistochemical analyses demonstrated clear increases in the number of collagen fibers and the expression of transforming growth factor-β1. Conclusion The short-term results showed that treatment with low energy level CO2 fractional laser therapy could be a safe and effective option for patients with Fitzpatrick skin Types III and IV who are concerned with enlarged pores.
- Published
- 2017
45. Seeking new acne treatment from natural products, devices and synthetic drug discovery
- Author
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Ji Hoon Yang, Seonguk Min, Hyuck Hoon Kwon, Dae Hun Suh, Ji Young Yoon, and Jungyoon Moon
- Subjects
0301 basic medicine ,natural products ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Chamaecyparis obtusa ,Photodynamic therapy ,Dermatology ,Review ,Pharmacology ,Bioinformatics ,Synthetic drugs ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,medicine ,acne ,Acne ,treatment ,lupeol ,business.industry ,Treatment options ,Acne treatment ,medicine.disease ,Clinical trial ,030104 developmental biology ,photodynamic therapy ,epigallocatechin-3 gallate ,business - Abstract
Despite lots of research on the pathogenesis of acne, the development of new therapeutic agents is still stagnant. Conventional agents which target multiple pathological processes have some serious side effects and this makes seeking new treatment options important for treating acne. As new therapeutic options, researchers are focusing on natural products, synthetic drugs and devices. From natural products, epigallocatechin-3 gallate, lupeol, cannabidiol and Lactobacillus fermented Chamaecyperis obtusa were reported to be possible candidates for novel drugs, targeting multiple pathogenic factors. Synthetic anti-P.acnes agent, nitric oxide nanoparticles and α-mangostin nanoparticles are shown to be effective in acne treatment. Device or procedural methods such as fractional microneedling radiofrequency, cryolysis, photothermolysis and daylight photodynamic therapy have potential as new treatment options for acne. Further large clinical trials comparing these new treatments with existing agents will be necessary in the future.
- Published
- 2017
46. Double-blind, randomized non-inferiority trial of a novel botulinum toxin A processed from the strain CBFC26, compared with onabotulinumtoxin A in the treatment of glabellar lines
- Author
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J. Y. Ahn, Beom Joon Kim, Hyuck Hoon Kwon, Seonguk Min, Dae Hun Suh, Ji Young Yoon, H. K. Lee, Seon Yong Park, Y. M. Park, and S. H. Seo
- Subjects
Adult ,Male ,medicine.medical_specialty ,Dermatology ,law.invention ,Botulinum toxin a ,Double blind ,Young Adult ,Double-Blind Method ,Randomized controlled trial ,law ,Clinical endpoint ,medicine ,Humans ,Botulinum Toxins, Type A ,Onabotulinumtoxin a ,Adverse effect ,Aged ,business.industry ,Middle Aged ,Skin Aging ,Surgery ,Infectious Diseases ,Face ,Anesthesia ,Non inferiority trial ,Female ,Early phase ,business - Abstract
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.
- Published
- 2014
47. Clinical effect of bovine amniotic membrane and hydrocolloid on wound by laser treatment: Prospective comparative randomized clinical trial
- Author
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Hyuck Hoon Kwon, Ji Y.oung Yoon, Seonguk Min, Dae Hun Suh, and Seon Yang Park
- Subjects
Hydrocolloid dressing ,medicine.medical_specialty ,integumentary system ,Erythema ,medicine.diagnostic_test ,business.industry ,food and beverages ,Scars ,Dermatology ,law.invention ,Surgery ,Occlusive dressing ,Randomized controlled trial ,law ,Skin biopsy ,Medicine ,medicine.symptom ,business ,Adverse effect ,Wound healing - Abstract
Bovine amniotic membrane (BAM) has been regarded as an ideal dressing material because it accelerates epithelization and has anti-inflammatory, anti-angiogenic, and strong analgesic effects. To evaluate the clinical effects of BAM and compare them to that of hydrocolloid dressings on wounds created by ablative laser treatments, 49 subjects with nevi or scars requiring ablative laser treatment were evaluated. To compare efficacy, we divided the body into six areas and included patients with two or more similar skin lesions in the same body area. After ablative laser treatments, BAM and hydrocolloid dressing were applied to the wounds with random allocation. Clinical assessments were performed at baseline, 1, 4, 6, 8, 11, and 13 days after treatment. Histologic changes were assessed by skin biopsy. BAM treatment induced faster epithelization than hydrocolloid treatment (6.7 vs. 9.2 days). Erythema and oozing faded more quickly, and the satisfaction score was higher in BAM-treated sites than it was in hydrocolloid-treated sites, without severe adverse effects. Histologic analysis confirmed epithelization and immunohistochemistry revealed different growth factor profiles between the two treatment modalities. BAM benefits wound healing following ablative laser treatment.
- Published
- 2014
48. Effect of Dietary Supplementation with Omega-3 Fatty Acid and Gamma-linolenic Acid on Acne Vulgaris: A Randomised, Double-blind, Controlled Trial
- Author
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Mi Sun Park, Jae Yoon Jung, Dae Hun Suh, Ji Young Yoon, Mi Young Jang, Hyuck Hoon Kwon, and Jong Soo Hong
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,Docosahexaenoic Acids ,Dermatology ,Gastroenterology ,law.invention ,Young Adult ,chemistry.chemical_compound ,Double-Blind Method ,Randomized controlled trial ,law ,Internal medicine ,Acne Vulgaris ,Humans ,Medicine ,Prospective Studies ,gamma-Linolenic acid ,Adverse effect ,Omega 3 fatty acid ,Acne ,chemistry.chemical_classification ,business.industry ,Interleukin-8 ,alpha-Linolenic Acid ,Fatty acid ,General Medicine ,medicine.disease ,Eicosapentaenoic acid ,Surgery ,Eicosapentaenoic Acid ,chemistry ,Docosahexaenoic acid ,Dietary Supplements ,Female ,business - Abstract
This study was undertaken to evaluate the clinical efficacy, safety, and histological changes induced by dietary omega-3 fatty acid and γ-linoleic acid in acne vulgaris. A 10-week, randomised, controlled parallel dietary intervention study was performed in 45 participants with mild to moderate acne, which were allocated to either an omega-3 fatty acid group (2,000 mg of eicosapentaenoic acid and docosahexaenoic acid), a γ-linoleic acid group (borage oil containing 400 mg γ-linoleic acid), or a control group. After 10 weeks of omega-3 fatty acid or γ-linoleic acid supplementation, inflammatory and non-inflammatory acne lesions decreased significantly. Patient subjective assessment of improvement showed a similar result. Heamatoxylin & eosin staining of acne lesions demonstrated reductions in inflammation and immunohistochemical staining intensity for interleukin-8. No severe adverse effect was reported. This study shows for the first time that omega-3 fatty acid and γ-linoleic acid could be used as adjuvant treatments for acne patients.
- Published
- 2014
49. An Effectiveness Analysis of Anti-Ballisitic Missile Launcher Arrangement for the Lower Tier Defense against the Ballistic Missile
- Author
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Yoon-Hwan Kim, Hyuck-Hoon Kwon, Kwan-Bum Choi, and Bum-Seok Lee
- Subjects
Engineering ,Missile ,business.industry ,Ballistic missile ,Aerodynamics ,Missile guidance ,Intermediate-range ballistic missile ,Aerospace engineering ,business ,Short-range ballistic missile - Abstract
For a lower tier defense, the distance between a launcher and an engagement control station is quite important to estimate the proper defense area and to effectively arrange missile launchers. In this paper, we have analyzed an effectiveness of anti-ballistic missile launcher arrangement for the lower tier defense against the ballistic missile. The operation concept, specific configuration and aerodynamic characteristics of the ballistic missile such as SCUD-B/C, Nodong are considered in order to develop a realistic engagement simulation. The diverse engagement results through numerical simulations are provided to conduct the effectiveness analysis of anti-ballistic missiles.
- Published
- 2013
50. Comparison between Er:YAG laser and bipolar radiofrequency combined with infrared diode laser for the treatment of acne scars: Differential expression of fibrogenetic biomolecules may be associated with differences in efficacy between ablative and non-ablative laser treatment
- Author
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Dae Hun Suh, Hyuck Hoon Kwon, Jungyoon Moon, Seonguk Min, Seon Yong Park, and Ji Young Yoon
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,Dermatology ,Lasers, Solid-State ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Cicatrix ,0302 clinical medicine ,Ablative case ,Acne Vulgaris ,medicine ,Humans ,Single-Blind Method ,Prospective Studies ,Acne ,medicine.diagnostic_test ,business.industry ,Tissue inhibitor of metalloproteinase ,Ablation ,medicine.disease ,Treatment Outcome ,030220 oncology & carcinogenesis ,Skin biopsy ,Collagenase ,Surgery ,Female ,Laser Therapy ,Lasers, Semiconductor ,Wound healing ,business ,Er:YAG laser ,medicine.drug - Abstract
Background and Objective Fractional Er:YAG minimizes the risk associated with skin ablation. Infrared diode laser and radiofrequency have suggested comparable improvements in acne scar. We compared the clinical efficacy of Er:YAG laser and bipolar radiofrequency combined with diode laser (BRDL) for the treatment of acne scars. Moreover, acute molecular changes of cytokine profile associated with wound healing have been evaluated to suggest mechanisms of improvement of acne scar. Study Design Twenty-four subjects with mild-to-moderate acne scars were treated in a split-face manner with Er:YAG and BRDL, with two treatment sessions, 4 weeks apart. Objective and subjective assessments were done at baseline, 1, 3, 7 days after each treatment and 4 weeks after last treatment. Skin biopsy specimens were obtained at baseline, 1, 3, 7, 28 days after one session of treatment for investigation of molecular profile of acute skin changes by laser treatment. Results Investigator's Global Assessment representing the improvement degree shows 2.1 (50%) in fractional Er:YAG and 1.2 (25%) in BRDL. Er:YAG induced the later and higher peak expression of TGFβs and collagenases, whereas BRDL induced earlier and lower expression of TGFβ and collagenases, relatively. PPARγ dropped rapidly after a peak in Er:YAG-treated side, which is associated with tissue inhibitor of metalloproteinase (TIMP) expression. We observed higher expression of TIMP after Er:YAG treatment compared with BRDL by immunohistochemistry, which may be associated with the expression of upregulation of collagen fibers. Conclusion The superior efficacy of Er:YAG to BRDL in the treatment of acne scars may be associated with higher expression of collagen which is associated with differential expression of TGFβs, collagenases, PPARγ, and TIMP. Lasers Surg. Med. 49:341–347, 2017. © 2016 Wiley Periodicals, Inc.
- Published
- 2016
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