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Low-temperature coating of Mn2O3-MoS2 micro-nano-heterostructure anode as an efficient catalyst for water splitting applications
No full textBinder-free Mn2O3-MoS2 hybrid composites (HCs) were fabricated using a room temperature kinetic spray process under low-pressure conditions with various weight ratios of Mn2O3-to-MoS2 (1:1, 1:2, and 1:4). The effect of the composition ratio on the electrocatalytic activity of Mn2O3-MoS2 HCs toward the oxygen evolution reaction (OER) in an alkaline medium was investigated. The deposited MoS2 exhibits microrods (MRs) morphology, while pure Mn2O3 exhibits nanoflakes (NFs) morphology. The Mn2O3-MoS2 HCs exhibited NFs-decorated MR morphology. Multilayer heterostructure morphology significantly improves the interfacial synergy between various electroactive species that were verified using various spectroscopic techniques such as micro-Raman and X-ray photoemission spectra. As the MoS2 content in the Mn2O3-MoS2 HCs increased, the interfacial charge transfer kinetics associated with the reduction in the oxidation barrier potential improved. The Mn2O3-MoS2 HCs with a 1:4 ratio demonstrated the optimum combination for OER with the smallest overpotential of 290 mV @ 10 mA cm-2 and Tafel slope of 41 mV dec-1. The long-term OER stability of the fabricated electrocatalysts was verified using chronopotentiometry techniques for 50 h at 50 mA cm-2
Enhancement of Semantic Segmentation by Image-Level Fine-Tuning to Overcome Image Pattern Imbalance in HRCT of Diffuse Infiltrative Lung Diseases
No full textDiagnosing diffuse infiltrative lung diseases (DILD) using high-resolution computed tomography (HRCT) is challenging, even for expert radiologists, due to the complex and variable image patterns. Moreover, the imbalances among the six key DILD-related patterns-normal, ground-glass opacity, reticular opacity, honeycombing, emphysema, and consolidation-further complicate accurate segmentation and diagnosis. This study presents an enhanced U-Net-based segmentation technique aimed at addressing these challenges. The primary contribution of our work is the fine-tuning of the U-Net model using image-level labels from 92 HRCT images that include various types of DILDs, such as cryptogenic organizing pneumonia, usual interstitial pneumonia, and nonspecific interstitial pneumonia. This approach helps to correct the imbalance among image patterns, improving the model's ability to accurately differentiate between them. By employing semantic lung segmentation and patch-level machine learning, the fine-tuned model demonstrated improved agreement with radiologists' evaluations compared to conventional methods. This suggests a significant enhancement in both segmentation accuracy and inter-observer consistency. In conclusion, the fine-tuned U-Net model offers a more reliable tool for HRCT image segmentation, making it a valuable imaging biomarker for guiding treatment decisions in patients with DILD. By addressing the issue of pattern imbalances, our model significantly improves the accuracy of DILD diagnosis, which is crucial for effective patient care
Trust, Long-term Orientation, and Relationship Performance: A Perspective of Distribution Management on Supply Chain
No full textPurpose: This study sheds light on the need for trust in buyer-seller relationships in supply chains and explores why long-term orientation is important. It also investigates the effect on relationship performance. This study provides implication on how to build robust supply chains.
Methodology: A survey was conducted with firms with supply chains in South Korea. A total of 350 valid questionnaires were analyzed through Entrust Survey-a sampling company. Structural equation modeling (SPSS 18.0 and AMOS) was employed to test the hypotheses.
Results: Cognitive trust had a positive effect on emotional trust. Emotional trust had a positive effect on long-term orientation but did not have a significant effect on relationship performance. Long-term orientation was proportionate to relationship performance.
Conclusions: Trust is a critical factor in supply chains. As business environments are rapidly changing, the uncertainties are also meaningful. Supply chains have collapsed owing to COVID-19, the Russia-Ukraine war, and the U.S.-China trade war, and they are only just recently being rebuilt. Maintaining relationships with supply-chain partners is vital, and promoting cognitive and emotional trust is necessary
경추 척수증에 있어서 황색 인대의 비후로 인한 후방 척수 압박이 경추 추간판 절제 및 유합술에 미치는 영향에 대한 연구
No full text연구 디자인: 후향적 코호트 연구
연구 목적: 전방 경추 추간판 절제 및 유합술 (anterior cervical discectomy and fusion, ACDF) 시행에 있어서 황색 인대 비후로 인한 척수 후방 압박 (cord compression by ligamentum flavum, CCLF)이 존재 유무ㅡ가 결과에 미치는 영향을 규명한다.
선행 문헌 요약: ACDF는 경추 척수증의 치료에 있어서 효과적으로 척수 전방에 존재하는 압박 구조물들을 제거할 수 있으며, 대부분 양호한 임상 결과를 나타내는 것으로 보고되어 있다. 하지만 ACDF는 척수 후방의 병변의 제거는 불가능하며, 이 때 CCLF의 존재가 수술의 결과에 어떠한 영향을 미치는지에 대해서는 아직 명확히 밝혀진 바가 없다.
연구 방법: 경추 척수증의 치료를 위해 ACDF를 시행 받고 2년 이상 추시 관찰된 195명의 환자에 대한 후향적 분석을 시행하였다. CCLF는 자기공명영상 검사의 시상면 영상 검사 소견에 따라 0-2 단계로 분류되었으며, CCLF 0,1단계인 경우를 no-CCLF군, CCLF 2단계의 경우를 CCLF군으로 정의하였다. 환자 임상 정보 및 경추 시상면 지표를 측정 분석하였으며, 임상 결과의 평가를 위해 목 통증 visual analogue scale (VAS), 팔 통증VAS, 그리고 일본 정형외과 학회 경추 척수증 점수 (Japanese Orthopedic Association score, JOA score)를 평가하였다.
결과: 167명의 (85.6%)의 환자들이 no-CCLF군으로 분류되었으며, 29명의 (14.4%)의 환자들이 CCLF군으로 분류되었다. CCLF군의 환자들 중에서 14명(50.0%)의 환자들은 JOA score로 평가한 임상 결과의 호전을 보였으며, 나머지 14명 (50.0%)의 경우 임상적 호전을 보이지 않았다. No-CCLF군에서는 수술 후 JOA score의 유의한 호전을 보였으나 (p<0.001), CCLF군에서는 유의한 호전을 보이지 못하였다 (p=0.642). 수술 후 3개월 (p=0.037) 및 2년 추시 시의 (p=0.001) JOA score는 no-CCLF군에서 CCLF군에 비해 유의하게 높게 평가되었다. 다변량 회귀 분석 상에서 CCLF는 수술 후 2년 추시 시의 JOA recovery rate와 유의한 연관성을 보였다 (p=0.045).
결론: CCLF 2단계가 관찰될 경우 ACDF의 임상적 결과는 CCLF 0, 1단계의 경우에 비해서 열등하였다. ACDF는 척수 후방 압박에 대한 효과적인 해결책이 될 수 없으며, CCLF가 척수 압박에 기여하는 경우 좋지 못한 임상 결과로 이어질 가능성이 있어 그 적용이 제한될 것으로 평가된다. Docto
The Immune Suppressor IGSF1 as a Potential Target for Cancer Immunotherapy
No full textThe development of first-generation immune-checkpoint inhibitors targeting PD-1/PD-L1 and CTLA-4 ushered in a new era in anticancer therapy. Although immune-checkpoint blockade therapies have shown clinical success, a substantial number of patients yet fail to benefit. Many studies are under way to discover next-generation immunotherapeutic targets. Immunoglobulin superfamily member 1 (IGSF1) is a membrane glycoprotein proposed to regulate thyroid function. Despite containing 12 immunoglobin domains, a possible role for IGSF1, in immune response, remains unknown. Here, our studies revealed that IGSF1 is predominantly expressed in tumors but not normal tissues, and increased expression is observed in PD-L1low non-small cell lung cancer (NSCLC) cells as compared with PD-L1high cells. Subsequently, we developed and characterized an IGSF1-specific human monoclonal antibody, WM-A1, that effectively promoted antitumor immunity and overcame the limitations of first-generation immune-checkpoint inhibitors, likely via a distinct mechanism of action. We further demonstrated high WM-A1 efficacy in humanized peripheral blood mononuclear cells (PBMC), and syngeneic mouse models, finding additive efficacy in combination with an anti-PD-1 (a well-characterized checkpoint inhibitor). These findings support IGSF1 as an immune target that might complement existing cancer immunotherapeutics
The origin of sequence type 72 community-associated methicillin-resistant Staphylococcus aureus (MRSA) and fusidic acid (FA) resistant sequence type 5 MRSA: Analysis of FA resistance and spa type in a single center in South Korea
No full textIntroduction: We investigated the prevalence of fusidic acid (FA) resistance in MSSA and MRSA stratified by sequence (ST) and spa types, and determined the prevalence of FA resistance mechanisms.
Methods: From August 2014 to April 2020, S. aureus blood isolates were collected in Asan Medical Center, Seoul, South Korea. Antimicrobial susceptibility tests were performed using broth microdilution and interpreted according to EUCAST's FA criteria. We performed spa typing for fusA mutation presence and acquired FA resistance determinants (fusB, fusC, and fusD) by PCR.
Results: Of the 590 MRSA isolates, 372 were FA resistant, and among 425 MSSA isolates, 136 were resistant. Of the 380 ST5-MRSA isolates, 350 were FA resistant, whereas only 1 of 14 ST5-MSSA isolates was FA resistant. Conversely, of the 163 ST72-MRSA isolates, only 8 were resistant, whereas 37 of 42 ST72-MSSA were resistant. The fusA mutation (80%) was the most common determinant. The one FA resistant ST5-MSSA isolate belonged to the t2460 spa type, the most common spa type (24 of 35 isolates) of FA resistant ST5-MRSA. In addition, t324 and t148, which are minor spa types of ST72-MSSA, were susceptible to FA, in contrast to other ST72-MSSA spa types, and the major spa type of ST72-MRSA (110 of 163 isolates).
Conclusions: FA resistance was common in ST5-MRSA and ST72-MSSA, and rare in ST5-MSSA and ST72-MRSA. Our findings suggest that minor clones of ST5-MSSA isolates, with the fusA mutation and minor clones of ST72-MSSA susceptible to FA, may have evolved to harbor the mecA gene
Ethanol Ablation of Ranulas and Risk Factor Analysis for Recurrence
No full textImportance: Ethanol ablation (EA) was shown to be safe and effective for treating ranula, but few studies have assessed long-term outcomes and recurrence of ranula after EA.
Objective: To evaluate the long-term outcomes and the risk factors for recurrence and receipt of subsequent surgery in patients who underwent treatment with EA for ranula.
Design, setting, and participants: This case-series study was conducted at a single tertiary hospital and assessed patients who were treated with EA between July 2009 and March 2021. Among 70 consecutive patients, those with follow-up loss or who were followed up for less than 24 months were excluded.
Exposures: EA for ranula.
Main outcomes and measures: The primary outcome was recurrence at last follow-up after single or multiple EA sessions. Secondary outcomes included receipt of subsequent surgery and the recurrence-free survival (RFS) rate after initial EA. Factors possibly associated with outcomes included patient age and sex; ranula site, type, diameter, volume, and echogenicity; the presentation-to-EA interval; parapharyngeal space extension; and sublingual gland herniation. Risk factors were identified on logistic regression analyses. Two-year RFS rates were analyzed for the initial cohort using the Kaplan-Meier method and compared by log-rank tests.
Results: A total of 57 patients (mean [SD] age, 26.4 [12.1] years; 24 female individuals [42%]) who were followed up for a median of 57 months (range, 24-167 months) were included. The recurrence rate was 33% (n = 19), and 11 (19%) underwent subsequent surgery. Among patients with recurrence, 86% (31 of 36) experienced first recurrence within 12 months after initial EA. A presentation-to-EA interval of 12 months or longer was associated with an increased risk of recurrence (adjusted odds ratio [OR], 3.74; 95% CI, 1.01-13.82). No risk factors were significantly associated with subsequent surgery (highest OR in parapharyngeal space extension: adjusted OR, 4.96; 95% CI, 0.94-26.35). Among the initial cohort of 70 patients, 2-year RFS was lower in a maximum diameter of ranula of 5 cm or greater than less than 5 cm (24% [95% CI, 7%-41%] vs 50% [95% CI, 34%-66%]; difference, 26% [95% CI, -4% to 56%]; log-rank test, P = .02).
Conclusions and relevance: This case-series study found that the recurrence rate of ranula after EA was 33%. A presentation-to-EA interval of 12 months or longer may be a risk factor for recurrence, suggesting that early intervention with EA might minimize recurrence. Most first recurrences occurred within 12 months after EA, with a maximum diameter of ranula of 5 cm or greater being a possible risk factor
Evaluation of the Fusion Rate and Safety of Escherichia coli-Derived rhBMP-2 in Transforaminal Lumbar Interbody Fusion for Patients with Degenerative Lumbar Disease: A Prospective, Multicenter, Single-Arm Trial
No full textBackground: Few studies have documented the viability of E. coli-derived recombinant human bone morphogenetic protein-2 (rhBMP-2) in transforaminal lumbar interbody fusion (TLIF). This study aimed to assess the safety and fusion rate of rhBMP-2 in TLIF. Methods: The study was conducted as a prospective, multicenter, single-arm trial, and 30 patients needing one- or two-level TLIF were enrolled. Fusion rate was assessed using the 12-month interbody fusion rate on CT. Postoperative problems, including seroma, radiculitis, and ectopic bone formation, which have been documented as risks associated with rhBMP-2 in prior studies, were recorded. Results: The study demonstrated fusion outcomes in all instances at 52 and 104 weeks post-surgery. Significant improvements were observed in clinical outcomes, with ODI, SF-36, and VAS scores, all achieving statistical significance (p < 0.0001). No perioperative adverse events requiring reoperation were reported, and there were no incidences of seroma, radiculitis, cage migration, grafted bone extrusion, postoperative neurologic deficit, or deep wound infection. Conclusions: The study demonstrates the high safety and efficacy in inducing bone fusion of E. coli-derived rhBMP-2 in TLIF, with a notable absence of adverse postoperative complications. Trial registration: This study protocol was registered at Korea Clinical Research Information Service (number identifier: KCT0004738) on July 2020
Evaluation of the Suitability of Digital Devices for Measuring Heart Rate Variability : A Comparative Analysis with ECG
No full textPurpose: The purpose of this study is to investigate the reliability of heart rate variability (HRV) measurements obtained through wearable devices and applications in comparison to those obtained from a medical-grade electrocardiogram (ECG) device.
Method: A total of 42 participants (14 males and 28 females; mean age: 32.19±12.07 years) were included in the study. The devices used in this study were the Polar H10, EliteHRV application, and the medical-grade ECG device SA-3000New. HRV parameters (heart rate, RMSSD, SDNN, TP, LF, and HF) were measured under three conditions (Rest, Stress, and Breathing), each for 5 minutes. To evaluate the agreement between HRV measurements from the ECG device and Polar+Elite HRV combination, correlation and Bland-Altman (BA) ratio analyses were conducted.
Results: The correlation coefficients between the two devices for heart rate, SDNN, RMSSD, TP, LF, and HF were 0.998, 0.991, 0.978, 0.850, 0.951, and 0.954, respectively. The BA ratio analysis showed BA ratios of 0.005, 0.077, 0.110, 0.407, 0.317, and 0.634 for heart rate, SDNN, RMSSD, TP, LF, and HF, respectively.
Conclusion: The study concluded that heart rate and time-domain HRV measurements calculated through the wearable device and application provided accurate and reliable signals comparable to those from the medical-grade ECG device. However, frequency-domain HRV measurements showed lower agreement and higher variability, indicating the need for caution when using these data for research purposes
Updated Definition of Healthy Alanine Aminotransferase Levels in a Metabolically and Histologically Normal Population
No full text배경: 이 연구에서는 전통적으로 40 U/L 으로 간주되었던 알라닌 아미노전이효소(ALT) 수치의 정상 상한치를 아시아인 생체 간이식 공여자들의 조직학적 그리고 대사적 척도들을 바탕으로 재평가하였다. 연구방법: 2006 년부터 2019 년까지 서울아산병원의 잠재적 생체 간이식 공여자 5,455 명을 대상으로 후향적 분석을 수행하였다. 모든 환자들의 B 형간염, C 형간염, 인간면역결핍바이러스, 음주력 여부가 평가되었다. 대사적 및 조직학적 정상 참가자들이 modified Prati criteria (체질량지수 <23 kg/m2, 중성지방 ≤200 mg/dL, 공복혈당 ≤105 mg/dL, 총콜레스테롤 ≤220 mg/dL)를 이용하여 평가되었다. 건강한 ALT 정상 상한치의 새로운 기준은 지방간이나 대사적 기능이상이 없는 참가자들의 95th percentile 값으로 정의하였다. 결과: 코호트 연령의 중간값은 30 세였으며 성별은 남성이 66.2%로 우세하였다. 모든 참가자들 중 3,162 명(58.0%)은 지방간이 없었고 이중 1,553 명(49.1%)은 modified Prati criteria 를 만족하여 대사적으로 건강하였다. 이 1,553 명에서 도출한 건강한 ALT 정상 상한치는 각각 남성에서 34U/L, 여성에서 22U/L 로 모두 통상적으로 사용되어왔던 기준인 40U/L 보다 유의미하게 낮았다. 지방간 또는 대사장애 위험이 있는 참가자들을 평가하기 위해‘경계성’ALT 범주(남성에서 34-40U/L, 여성에서 22-40U/L)가 새롭게 도입되었다. 결론: 전통적인 ALT 정상 상한치는 대사적 및 조직학적으로 검증된 아시아 인구에서 새롭게 도출한 건강한 ALT 정상 상한치에 비해 높았다. 이 연구에서 제시하는 ALT 정상 상한치는 각각 남성에서 34U/L, 여성에서 22U/L 이다. ‘경계성’ALT 범주의 도입은 간질환 및 대사질환 위험군의 분류에 도움이 되었으며 이는 ALT 정상 상한치의 개정 필요성을 강조하고 있다. 중심단어: 알라닌 아미노전이효소; 지방간; 정상 상한치|Background and Aims: This study re-evaluates the upper limit of normal (ULN) for alanine aminotransferase (ALT), traditionally set at 40 U/L, using histological and metabolic parameters in Asian living liver donor. Methods: We conducted a retrospective analysis of 5,455 potential living liver donors from 2005 to 2019. Patients were screened for hepatitis B, C, HIV, and alcohol use. Histologically and metabolically healthy participants was assessed using the modified Prati criteria (body mass index <23 kg/m2, triglyceride ≤200 mg/dL, fasting glucose ≤105 mg/dL, total cholesterol ≤220 mg/dL). The new healthy ULN of ALT was determined at the 95th percentile among participants without hepatic steatosis or metabolic dysfunction. Results: The median age of the cohort was 30 years with a predominance of males (66.2%). Among all participants, 3,162 (58.0%) were without hepatic steatosis, and 1,553 (49.1%) met the modified Prati criteria, being metabolically healthy. The new healthy ULN of these 1,553 individuals was 34 U/L for males and 22 U/L for females, significantly lower than the conventional 40 U/L. A ‘borderline’ ALT category (34-40 U/L for males, 22-40 U/L for females) was also introduced to participants at risk of hepatic steatosis or metabolic dysfunction. Conclusion: The traditional ALT ULN is higher than healthy levels for a metabolically and histologically verified Asian population. The proposed ULN values are 34 U/L for males and 22 U/L for females. The introduction of a ‘borderline’ category aids in better disease risk stratification, highlighting the need for an updated ULN for ALT. Keywords: Alanine aminotransferase, hepatic steatosis, upper limit of normal.Maste