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.Detection Ability of Quality of Life Changes and Responsiveness of the KOQUSS-40 and the EORTC QLQ-C30/STO22 in Patients Who Underwent Gastrectomy: A Prospective Comparative Study
Bang Wool EOM ; Keun Won RYU ; Ji Yeong AN ; Yun-Suhk SUH ; In CHO ; Sung Geun KIM ; Ji-Ho PARK ; Hoon HUR ; Hyung-Ho KIM ; Sang-Hoon AHN ; Sun-Hwi HWANG ; Hong Man YOON ; Ki Bum PARK ; Hyoung-Il KIM ; In-Gyu KWON ; Han-Kwang YANG ; Byoung-Jo SUH ; Sang-Ho JEONG ; Tae-Han KIM ; Oh Kyoung KWON ; Hye-Seong AHN ; Ji Yeon PARK ; Ki Young YOON ; Myoung Won SON ; Seong-Ho KONG ; Young-Gil SON ; Geum Jong SONG ; Jong Hyuk YUN ; Jung-Min BAE ; Do Joong PARK ; Sol LEE ; Jun-Young YANG ; Kyung Won SEO ; You-Jin JANG ; So Hyun KANG ; Joongyub LEE ; Hyuk-Joon LEE ;
Cancer Research and Treatment 2026;58(1):221-231
Purpose:
The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ).
Materials and Methods:
A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire.
Results:
Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ.
Conclusion
KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.
3.Prospective Multicenter Observational Study on Postoperative Quality of Life According to Type of Gastrectomy for Gastric Cancer
Sung Eun OH ; Yun-Suhk SUH ; Ji Yeong AN ; Keun Won RYU ; In CHO ; Sung Geun KIM ; Ji-Ho PARK ; Hoon HUR ; Hyung-Ho KIM ; Sang-Hoon AHN ; Sun-Hwi HWANG ; Hong Man YOON ; Ki Bum PARK ; Hyoung-Il KIM ; In Gyu KWON ; Han-Kwang YANG ; Byoung-Jo SUH ; Sang-Ho JEONG ; Tae-Han KIM ; Oh Kyoung KWON ; Hye Seong AHN ; Ji Yeon PARK ; Ki Young YOON ; Myoung Won SON ; Seong-Ho KONG ; Young-Gil SON ; Geum Jong SONG ; Jong Hyuk YUN ; Jung-Min BAE ; Do Joong PARK ; Sol LEE ; Jun-Young YANG ; Kyung Won SEO ; You-Jin JANG ; So Hyun KANG ; Bang Wool EOM ; Joongyub LEE ; Hyuk-Joon LEE ;
Journal of Gastric Cancer 2025;25(2):382-399
Purpose:
This study evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer.
Materials and Methods:
A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery.
Results:
Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064).
Conclusions
Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.
4.Prospective Multicenter Observational Study on Postoperative Quality of Life According to Type of Gastrectomy for Gastric Cancer
Sung Eun OH ; Yun-Suhk SUH ; Ji Yeong AN ; Keun Won RYU ; In CHO ; Sung Geun KIM ; Ji-Ho PARK ; Hoon HUR ; Hyung-Ho KIM ; Sang-Hoon AHN ; Sun-Hwi HWANG ; Hong Man YOON ; Ki Bum PARK ; Hyoung-Il KIM ; In Gyu KWON ; Han-Kwang YANG ; Byoung-Jo SUH ; Sang-Ho JEONG ; Tae-Han KIM ; Oh Kyoung KWON ; Hye Seong AHN ; Ji Yeon PARK ; Ki Young YOON ; Myoung Won SON ; Seong-Ho KONG ; Young-Gil SON ; Geum Jong SONG ; Jong Hyuk YUN ; Jung-Min BAE ; Do Joong PARK ; Sol LEE ; Jun-Young YANG ; Kyung Won SEO ; You-Jin JANG ; So Hyun KANG ; Bang Wool EOM ; Joongyub LEE ; Hyuk-Joon LEE ;
Journal of Gastric Cancer 2025;25(2):382-399
Purpose:
This study evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer.
Materials and Methods:
A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery.
Results:
Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064).
Conclusions
Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.
5.Prospective Multicenter Observational Study on Postoperative Quality of Life According to Type of Gastrectomy for Gastric Cancer
Sung Eun OH ; Yun-Suhk SUH ; Ji Yeong AN ; Keun Won RYU ; In CHO ; Sung Geun KIM ; Ji-Ho PARK ; Hoon HUR ; Hyung-Ho KIM ; Sang-Hoon AHN ; Sun-Hwi HWANG ; Hong Man YOON ; Ki Bum PARK ; Hyoung-Il KIM ; In Gyu KWON ; Han-Kwang YANG ; Byoung-Jo SUH ; Sang-Ho JEONG ; Tae-Han KIM ; Oh Kyoung KWON ; Hye Seong AHN ; Ji Yeon PARK ; Ki Young YOON ; Myoung Won SON ; Seong-Ho KONG ; Young-Gil SON ; Geum Jong SONG ; Jong Hyuk YUN ; Jung-Min BAE ; Do Joong PARK ; Sol LEE ; Jun-Young YANG ; Kyung Won SEO ; You-Jin JANG ; So Hyun KANG ; Bang Wool EOM ; Joongyub LEE ; Hyuk-Joon LEE ;
Journal of Gastric Cancer 2025;25(2):382-399
Purpose:
This study evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer.
Materials and Methods:
A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery.
Results:
Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064).
Conclusions
Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.
6.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.
7.Is the Ossification of the Posterior Longitudinal Ligament a Positive Factor for the Fusion after Posterior Cervical Fusion and Decompression?
Jun-Woo HA ; Bong Ju MOON ; Kwang-Ryeol KIM ; Kyung Hyun KIM ; Jeong Yoon PARK ; Dong Kyu CHIN ; Yong Eun CHO ; Keun Su KIM ; Hyun Jun JANG
The Nerve 2024;10(2):89-97
Objective:
Multilevel posterior cervical fusion (PCF) and decompression surgery is a viable treatment option for multilevel ossification of posterior longitudinal ligament (OPLL) and spondylotic myelopathy. Since OPLL is known to affect bone formation, this study aimed to examine the effect of OPLL on the incidence of pseudarthrosis following PCF in a cohort study.
Methods:
We conducted a retrospective cohort study of patients with PCF and laminectomy at our institution. This study included patients who underwent C3 to C6 posterior fusion surgery involving lateral mass screw fixation without anterior surgery for OPLL or spondylotic myelopathy. Fusion status was evaluated 1 year postoperatively with computed tomography. Bone mineral density (BMD) and sagittal parameters were also evaluated as potential contributing factors to the fusion rate.
Results:
Eighty patients were included. Pseudarthrosis was observed in 22.5% (n=18) of patients. Pseudarthrosis incidence was lower in patients with OPLL (spondylosis vs. OPLL, 33.3% vs. 12.2%; p=0.003), and a higher BMD T-score (pseudarthrosis vs. fusion, -1.9 ± 0.7 vs. -0.6 ± 1.3; p<0.01), a larger preoperative range of motion (ROM) (26.7 ± 13.3 vs. 17.6 ± 10.9; p=0.01), and a greater preoperative-to-postoperative decrease in cervical lordosis (-8.1 ± 7.9 vs. -2.7 ± 7.9; p<0.01). Pseudarthrosis was associated with worsening neck pain after surgery.
Conclusion
The absence of OPLL, lower BMD, larger preoperative ROM, and a greater decrease in postoperative cervical lordosis were identified as risk factors for pseudarthrosis after multiple PCF.
8.Quality Indicators of Endoscopic Retrograde Cholangiopancreatography in Korea
Ki-Hyun KIM ; Hyung Ku CHON ; Tae Jun SONG ; Dong Won AHN ; Eaum Seok LEE ; Yun Nah LEE ; Yoon Suk LEE ; Tae Joo JEON ; Chang Hwan PARK ; Kwang Bum CHO ; Dong Wook LEE ; Jin-Seok PARK ; Seung Bae YOON ; Kwang Hyung CHUNG ; Jin LEE ; Miyoung CHOI
The Korean Journal of Gastroenterology 2024;84(3):111-122
Endoscopic retrograde cholangiopancreatography (ERCP) is a procedure that requires abundant clinical experience and endoscopic skills, and can lead to various complications, some of which may progress to life-threatening conditions. With expanding indications and technological advancements, ERCP is widely utilized, enhancing procedural accessibility. However, without proper quality management, the procedure can pose significant risks. Quality management in ERCP is essential to ensure safe and successful procedures and meet societal demands for improved healthcare competitiveness. To address these concerns, the Korean Society of Pancreatobiliary Endoscopy has developed a Korean-specific ERCP quality indicator reflecting domestic medical environments and realities. Initially, based on a review of foreign ERCP quality indicators and related literatures, key questions were formulated for five pre-procedural items, three intra-procedural items, and four post-procedural items. Descriptions and recommendations for each item were selected through peer evaluation. The developed Korean-specific ERCP quality indicator was reviewed by external experts based on the latest evidence and consensus in this fields. This Korean-specific indicator is expected to significantly contribute to improving ERCP quality in Korea, as it is tailored to local needs.
9.Gut microbiome and metabolome signatures in liver cirrhosis-related complications
Satya Priya SHARMA ; Haripriya GUPTA ; Goo-Hyun KWON ; Sang Yoon LEE ; Seol Hee SONG ; Jeoung Su KIM ; Jeong Ha PARK ; Min Ju KIM ; Dong-Hoon YANG ; Hyunjoon PARK ; Sung-Min WON ; Jin-Ju JEONG ; Ki-Kwang OH ; Jung A EOM ; Kyeong Jin LEE ; Sang Jun YOON ; Young Lim HAM ; Gwang Ho BAIK ; Dong Joon KIM ; Ki Tae SUK
Clinical and Molecular Hepatology 2024;30(4):845-862
Background/Aims:
Shifts in the gut microbiota and metabolites are interrelated with liver cirrhosis progression and complications. However, causal relationships have not been evaluated comprehensively. Here, we identified complication-dependent gut microbiota and metabolic signatures in patients with liver cirrhosis.
Methods:
Microbiome taxonomic profiling was performed on 194 stool samples (52 controls and 142 cirrhosis patients) via V3-V4 16S rRNA sequencing. Next, 51 samples (17 controls and 34 cirrhosis patients) were selected for fecal metabolite profiling via gas chromatography mass spectrometry and liquid chromatography coupled to timeof-flight mass spectrometry. Correlation analyses were performed targeting the gut-microbiota, metabolites, clinical parameters, and presence of complications (varices, ascites, peritonitis, encephalopathy, hepatorenal syndrome, hepatocellular carcinoma, and deceased).
Results:
Veillonella bacteria, Ruminococcus gnavus, and Streptococcus pneumoniae are cirrhosis-related microbiotas compared with control group. Bacteroides ovatus, Clostridium symbiosum, Emergencia timonensis, Fusobacterium varium, and Hungatella_uc were associated with complications in the cirrhosis group. The areas under the receiver operating characteristic curve (AUROCs) for the diagnosis of cirrhosis, encephalopathy, hepatorenal syndrome, and deceased were 0.863, 0.733, 0.71, and 0.69, respectively. The AUROCs of mixed microbial species for the diagnosis of cirrhosis and complication were 0.808 and 0.847, respectively. According to the metabolic profile, 5 increased fecal metabolites in patients with cirrhosis were biomarkers (AUROC >0.880) for the diagnosis of cirrhosis and complications. Clinical markers were significantly correlated with the gut microbiota and metabolites.
Conclusions
Cirrhosis-dependent gut microbiota and metabolites present unique signatures that can be used as noninvasive biomarkers for the diagnosis of cirrhosis and its complications.
10.Quality Indicators of Endoscopic Retrograde Cholangiopancreatography in Korea
Hyung Ku CHON ; Ki-Hyun KIM ; Tae Jun SONG ; Dong-Won AHN ; Eaum Seok LEE ; Yun Nah LEE ; Yoon Suk LEE ; Tae Joo JEON ; Chang Hwan PARK ; Kwang Bum CHO ; Dong Wook LEE ; Jin-Seok PARK ; Seung Bae YOON ; Kwang Hyun CHUNG ; Jin LEE ; Miyoung CHOI
Gut and Liver 2024;18(4):564-577
Endoscopic retrograde cholangiopancreatography (ERCP) is a procedure that requires significant experiences and skills and has various procedure-related complications, some of which can be severe and even result in the death of patients. Expanding ERCP availability has the advantage of increasing accessibility for patients. However, ERCP poses a substantial risk if performed without proper quality management. ERCP quality management is essential for both ensuring safe and successful procedures and meeting the social demands for enhanced healthcare competitiveness and quality assurance. To address these concerns, the Korean Pancreatobiliary Association established a task force to develop ERCP quality indicators (QIs) tailored to the Korean medical environment. Key questions for five pre-procedure, three intra-procedure, and four post-procedure measures were formulated based on a literature search related to ERCP QIs and a comprehensive clinical review conducted by experts. The statements and recommendations regarding each QI item were selected through peer review. The developed ERCP QIs were reviewed by external experts based on the latest available evidence at the time of development.These domestically tailored ERCP QIs are expected to contribute considerably to improving ERCP quality in Korea.

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