1.Thermal modulation and airflow distribution determine hair drying efficiency, moisture behavior in human hair in Republic of Korea: an ex vivo study
Tae-Rin KWON ; Doohyun HAN ; Hyoung Jun KIM ; Jungwook KIM ; Byung Ho YOON ; Sung Yong PARK ; Jun-Seok LEE ; Na Mi BYUN ; Jungkwan LEE ; Jungwon LEE ; Kwang Ho YOO
Medical Lasers 2026;15(1):69-76
Background:
Hair drying is a routine cosmetic practice; however, excessive heat exposure and non-uniform airflow can compromise cuticle integrity, degrade hair sensory properties, and induce scalp discomfort. This study aimed to (i) identify a practical thermal window that minimizes perturbation of hair fiber surface and quantify late-stage thermal amplification during the drying process using percentage-based analysis.
Methods:
Temperature-dependent hair fiber surface morphology was examined by scanning electron microscopy (SEM) after controlled exposure to 41°C, 60°C, 80°C, and 90°C using virgin and chemically damaged hair. The drying efficacy was assessed using the surface and internal moisture indices under airflow shaping (test) and uniform airflow (control) conditions. Hair fluttering (maximum angular displacement) was evaluated before and after drying under warm-cool alternating (60°C-80°C) versus constant hot airflow (80°C).
Results:
SEM revealed temperature-dependent cuticle disruption, with markedly greater surface perturbation at 90°C than at 80°C. Infrared thermography demonstrated pronounced late-stage thermal amplification: at 150 seconds, the surface temperature increased by 295% (from 24.2°C to 72.0°C) at 90°C, compared with 207% (from 24.2°C to 50.7°C) at 80°C. Airflow shaping promoted preferential surface moisture removal (–13.6%) while limiting internal dehydration (–9.4%), whereas the control condition exhibited minimal surface drying (–4.6%) but substantial internal moisture loss (–22.2%). Warm-cool modulation increased hair fluttering by +11.0%, whereas constant hot airflow reduced it (–3.7%).
Conclusion
These findings indicate that spatial and temporal control of heat delivery represents a clinically relevant design strategy beyond the nominal temperature specification in hair-drying devices.
2.Effect of cosmetic ingredients as functional agents:synergistic action of electroporation and sonophoresis in clinical efficacy
Tae-Rin KWON ; Jungwook KIM ; Soo Min KIM ; Hyoung Jun KIM ; Jungkwan LEE ; Kwang Ho YOO
Medical Lasers 2025;14(1):16-22
Background:
This study examined the effects of electroporation (EP) and sonophoresis (SP) on the skin permeation of various ingredients and the resulting changes in skin properties.
Methods:
Twenty participants used whitening and hyaluronic ampoules as adjunctive cosmetics. The intervention group used an EP with an SP device for application while the control group used their hands, both groups over a 4-week period. The outcomes measured included skin elasticity, gloss, pores, tone, and soothing.In addition, this study determined the absorption amount, absorption rate, and skin permeation of the cosmetic ampoules 30 minutes after applying the cosmetics in a clinical test.
Results:
Significant improvements in skin hydration, elasticity, tone, and pigmentation were observed in the intervention group. In particular, the most pronounced effects were observed immediately after use. In addition, application with EP and SP led to a more than 200% increase in the absorption amount, absorption depth, and absorption speed of cosmetics compared to hand application.
Conclusion
These findings suggest that simultaneous EP and SP significantly enhance skin permeability and cosmetic absorption, improving skin properties.
3.Enhancing collagen synthesis and improving dermal delivery of hyaluronic acid and anti-oxidant ampoule via simultaneous electroporation and low-frequency sonophoresis
Tae-Rin KWON ; Jungwook KIM ; Soo Min KIM ; Hyoung Jun KIM ; Jungkwan LEE ; Kwang Ho YOO
Medical Lasers 2025;14(1):31-38
Background:
The delivery of desired drugs through the skin can enhance the effectiveness of cosmetic treatments and further enhance skin recovery and collagen regeneration. This study evaluated the potential of a device to achieve noninvasive transdermal drug delivery using simultaneous electroporation (EP) and lowfrequency sonophoresis (SP).
Methods:
The percutaneous absorption after applying the device that administered EP and SP was evaluated using an ex vivo porcine skin model. Porcine skin tissue was placed on a polyurethane foam dressing impregnated with 3% povidone-iodine (PI). Four drops of ampoule were applied, and the device was applied to the skin for 3 minutes. The reaction between the penetrated whitening agents and 3% PI, indicated by color changes, was analyzed using an Antera 3D camera.
Results:
The simultaneous application of EP with SP to skin tissue at a specific ratio for 3 minutes resulted in a significant increase in the area that reacted with iodine after skin penetration. The results showed that exposure to hyaluronic acid ampoule (HAA) increases type I collagen synthesis in human dermal fibroblasts in a concentration- and time-dependent manner. In addition, treatment with HAA combined with the application of EP with SP increased cell proliferation and significantly increased type I collagen levels in human dermal fibroblasts, with device-assisted synthesis showing greater efficiency.
Conclusion
These results suggest that simultaneous EP and SP efficiently deliver large molecules, such as hyaluronic acid, deep into the skin without causing skin damage.
4.Thermal cycling with focused airflow prevents α-keratin denaturation and structural damage in human hair in Korea:an ex vivo study
Tae-Rin KWON ; Doohyun HAN ; Jungwook KIM ; Hyoung Jun KIM ; Byung Ho YOON ; Dong Wook MOON ; Jungkwan LEE ; Kwang Ho YOO
Medical Lasers 2025;14(3):168-174
Background:
Excessive heat from household styling devices denatures α-keratin, damages the cuticle, and degrades overall hair quality. Conventional blow-dryer temperatures often exceed 90°C, surpassing the safety threshold for keratin fibers. To determine whether combining focused airflow with rapid thermal cycling (peak temperatures ≤60°C) attenuates multiscale hair damage compared with continuous-heat drying.
Methods:
Human-hair tresses were assigned either to a focused-flow dryer operating in alternating cool/warm cycles or to a continuous-heat mode. Jet characteristics were quantified using planar particle-image velocimetry, and airflow temperatures were recorded using micro-thermocouples. Post-treatment analyses included scanning electron microscopy (cuticular surface roughness, Ra), single-fiber tensile testing, crosssectional densitometry (fiber compactness), and confocal Raman spectroscopy (α-helix/disulfide bond integrity).
Results:
Thermal cycling with focused airflow increased the central-core flow fraction from 37% to 64% and confined hair-surface peaks to 58°C-60°C. Alternating hot-cold drying reduced cuticlar surface roughness by approximately 7.3%, whereas continuous hat air drying increased roughness by 4.9%. Ultimate tensile strength was essentially preserved (–0.4%) under cycling but fell by 9.4% with uninterrupted heat (p = 0.003).Compactness loss was limited to 33% vs. 50%, and the S-S disulfide bond (~510 cm –1 )/C-H bending vibration band (~720 cm –1 ) ratio decreased by only 11% (vs. 19% under continuous heat).
Conclusion
Brief cooling intervals, when paired with a confined airflow, effectively prevented α-keratindenaturation and structural collapse. These findings support a clinically relevant approach to preserving hairfiber integrity during routine hair care and styling.
5.ERRATUM: Recommendations for the Use of Next-Generation Sequencing and the Molecular Tumor Board for Patients with Advanced Cancer: A Report from KSMO and KCSG Precision Medicine Networking Group
Shinkyo YOON ; Miso KIM ; Yong Sang HONG ; Han Sang KIM ; Seung Tae KIM ; Jihun KIM ; Hongseok YUN ; Changhoon YOO ; Hee Kyung AHN ; Hyo Song KIM ; In Hee LEE ; In-Ho KIM ; Inkeun PARK ; Jae Ho JEONG ; Jaekyung CHEON ; Jin Won KIM ; Jina YUN ; Sun Min LIM ; Yongjun CHA ; Se Jin JANG ; Dae Young ZANG ; Tae Won KIM ; Jin Hyoung KANG ; Jee Hyun KIM
Cancer Research and Treatment 2023;55(3):1061-1061
6.Recommendations for the Use of Next-Generation Sequencing and the Molecular Tumor Board for Patients with Advanced Cancer: A Report from KSMO and KCSG Precision Medicine Networking Group
Shinkyo YOON ; Miso KIM ; Yong Sang HONG ; Han Sang KIM ; Seung Tae KIM ; Jihun KIM ; Hongseok YUN ; Changhoon YOO ; Hee Kyung AHN ; Hyo Song KIM ; In Hee LEE ; In-Ho KIM ; Inkeun PARK ; Jae Ho JEONG ; Jaekyung CHEON ; Jin Won KIM ; Jina YUN ; Sun Min LIM ; Yongjun CHA ; Se Jin JANG ; Dae Young ZANG ; Tae Won KIM ; Jin Hyoung KANG ; Jee Hyun KIM
Cancer Research and Treatment 2022;54(1):1-9
Next-generation sequencing (NGS) is becoming essential in the fields of precision oncology. With implementation of NGS in daily clinic, the needs for continued education, facilitated interpretation of NGS results and optimal treatment delivery based on NGS results have been addressed. Molecular tumor board (MTB) is multidisciplinary approach to keep pace with the growing knowledge of complex molecular alterations in patients with advanced solid cancer. Although guidelines for NGS use and MTB have been developed in western countries, there is limitation for reflection of Korea’s public health environment and daily clinical practice. These recommendations provide a critical guidance from NGS panel testing to final treatment decision based on MTB discussion.
7.Atypical Teratoid/Rhabdoid Tumor of the Central Nervous System in Children under the Age of 3 Years
Meerim PARK ; Jung Woo HAN ; Seung Min HAHN ; Jun Ah LEE ; Joo-Young KIM ; Sang Hoon SHIN ; Dong-Seok KIM ; Hong In YOON ; Kyung Taek HONG ; Jung Yoon CHOI ; Hyoung Jin KANG ; Hee Young SHIN ; Ji Hoon PHI ; Seung-Ki KIM ; Ji Won LEE ; Keon Hee YOO ; Ki Woong SUNG ; Hong Hoe KOO ; Do Hoon LIM ; Hyung Jin SHIN ; Hyery KIM ; Kyung-Nam KOH ; Ho Joon IM ; Seung Do AHN ; Young-Shin RA ; Hee-Jo BAEK ; Hoon KOOK ; Tae-Young JUNG ; Hyoung Soo CHOI ; Chae-Yong KIM ; Hyeon Jin PARK ; Chuhl Joo LYU
Cancer Research and Treatment 2021;53(2):378-388
Purpose:
Atypical teratoid/rhabdoid tumor (ATRT) is a highly aggressive malignancy with peak incidence in children aged less than 3 years. Standard treatment for central nervous system ATRT in children under the age of 3 years have not been established yet. The objective of this study was to analyze characteristics and clinical outcomes of ATRT in children aged less than 3 years.
Materials and Methods:
A search of medical records from seven centers was performed between January 2005 and December 2016.
Results:
Forty-three patients were enrolled. With a median follow-up of 90 months, 27 patients (64.3%) showed at least one episode of disease progression (PD). The first date of PD was at 160 days after diagnosis. The 1- and 3-year progression-free survivals (PFS) were 51.2% and 28.5%, respectively. The 1- and 3-year overall survivals were 61.9% and 38.1%, respectively. The 3-year PFS was improved from 0% in pre-2011 to 47.4% in post-2011. Excluding one patient who did not receive any further therapy after surgery, 27 patients died due to PD (n=21), treatment-related toxicity (n=5), or unknown cause (n=1). In univariate analysis, factors associated with higher 3-year PFS were no metastases, diagnosis after 2011, early adjuvant radiotherapy, and high-dose chemotherapy (HDCT). In multivariate analysis, the use of HDCT and adjuvant radiotherapy remained significant prognostic factors for PFS (both p < 0.01).
Conclusion
Aggressive therapy including early adjuvant radiotherapy and HDCT could be considered to improve outcomes of ATRT in children under the age of 3 years.
8.Atypical Teratoid/Rhabdoid Tumor of the Central Nervous System in Children under the Age of 3 Years
Meerim PARK ; Jung Woo HAN ; Seung Min HAHN ; Jun Ah LEE ; Joo-Young KIM ; Sang Hoon SHIN ; Dong-Seok KIM ; Hong In YOON ; Kyung Taek HONG ; Jung Yoon CHOI ; Hyoung Jin KANG ; Hee Young SHIN ; Ji Hoon PHI ; Seung-Ki KIM ; Ji Won LEE ; Keon Hee YOO ; Ki Woong SUNG ; Hong Hoe KOO ; Do Hoon LIM ; Hyung Jin SHIN ; Hyery KIM ; Kyung-Nam KOH ; Ho Joon IM ; Seung Do AHN ; Young-Shin RA ; Hee-Jo BAEK ; Hoon KOOK ; Tae-Young JUNG ; Hyoung Soo CHOI ; Chae-Yong KIM ; Hyeon Jin PARK ; Chuhl Joo LYU
Cancer Research and Treatment 2021;53(2):378-388
Purpose:
Atypical teratoid/rhabdoid tumor (ATRT) is a highly aggressive malignancy with peak incidence in children aged less than 3 years. Standard treatment for central nervous system ATRT in children under the age of 3 years have not been established yet. The objective of this study was to analyze characteristics and clinical outcomes of ATRT in children aged less than 3 years.
Materials and Methods:
A search of medical records from seven centers was performed between January 2005 and December 2016.
Results:
Forty-three patients were enrolled. With a median follow-up of 90 months, 27 patients (64.3%) showed at least one episode of disease progression (PD). The first date of PD was at 160 days after diagnosis. The 1- and 3-year progression-free survivals (PFS) were 51.2% and 28.5%, respectively. The 1- and 3-year overall survivals were 61.9% and 38.1%, respectively. The 3-year PFS was improved from 0% in pre-2011 to 47.4% in post-2011. Excluding one patient who did not receive any further therapy after surgery, 27 patients died due to PD (n=21), treatment-related toxicity (n=5), or unknown cause (n=1). In univariate analysis, factors associated with higher 3-year PFS were no metastases, diagnosis after 2011, early adjuvant radiotherapy, and high-dose chemotherapy (HDCT). In multivariate analysis, the use of HDCT and adjuvant radiotherapy remained significant prognostic factors for PFS (both p < 0.01).
Conclusion
Aggressive therapy including early adjuvant radiotherapy and HDCT could be considered to improve outcomes of ATRT in children under the age of 3 years.
9.Osteoporosis and Osteoporotic Fracture Fact Sheet in Korea
Seong Hee AHN ; Sang-Min PARK ; So Young PARK ; Jun-Il YOO ; Hyoung-Seok JUNG ; Jae-Hwi NHO ; Se Hwa KIM ; Young-Kyun LEE ; Yong-Chan HA ; Sunmee JANG ; Tae-Young KIM ; Ha Young KIM
Journal of Bone Metabolism 2020;27(4):281-290
Background:
The socioeconomic burdens of osteoporosis and related fractures have increased in parallel with population aging. The Korea Society of Bone and Mineral Research published fact sheets on these topics in 2017, 2018, and 2019. This study provides complied epidemiological data based on these fact sheets for understanding current status of osteoporosis in Korea.
Methods:
Data from the Korea National Health and Nutrition Examination Survey (2008-2011) performed by the Korea Centers for Disease Control and Prevention and from National Health Information database (2008-2016) by National Health Insurance Service of Korea was used for analyzing the prevalence and incidence of osteoporosis and related fractures, respectively, fatality rates after fractures, and prescription status of anti-osteoporotic medications (AOMs).
Results:
Among Korean adults aged ≥50 years, 22.4% and 47.9% had osteopenia or osteoporosis, respectively. Incidences of osteoporotic hip, vertebral, humerus, and distal radius fractures plateaued in 2013. The cumulative incidence of subsequent fractures gradually increased over 4 years of follow-up once an osteoporotic fracture occurred. Crude fatality rates in the first 12 months after hip fracture were 14.0% for women and 21.0% for men. Only 33.5% of patients with osteoporosis took AOMs, and even after an osteoporotic fracture, only 41.9% of patients took AOMs within the following 12 months. Despite a steady increase in AOM prescriptions of ~6% per annum, only 33.2% of patients were medication compliant (medication possession ratio ≥80%) at 12 months after treatment initiation.
Conclusions
Continuous efforts are required to diagnose patients at high risk of fracture and ensure proper management in Korea.
10.Validation of Previous Spirometric Reference Equations and New Equations
Hye Sook CHOI ; Yong Bum PARK ; Hyoung Kyu YOON ; Seong Yong LIM ; Tae Hyung KIM ; Joo Hun PARK ; Won Yeon LEE ; Seoung Ju PARK ; Sei Won LEE ; Woo Jin KIM ; Ki Uk KIM ; Kyeong Cheol SHIN ; Do Jin KIM ; Tae Eun KIM ; Kwang Ha YOO ; Jae Jeong SHIM ; Yong Il HWANG
Journal of Korean Medical Science 2019;34(47):304-

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