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로봇 신장 이식후 지연된 수술후 체류 기간 예측: 수술 전후 위험 인자 개발 및 시뮬레이션
No full textBackground and Objective: Early discharge following robot-assisted kidney transplantation (RAKT) is a cost-effective strategy for reducing healthcare expenses while maintaining favorable short- and long-term prognoses. This study aims to identify predictors of postoperative delayed discharge in RAKT patients and develop a predictive model to enhance clinical outcomes.
Materials and Methods: This retrospective study included 146 patients aged 18 years and older who underwent RAKT at a single tertiary medical center from August 2020 to January 2024. Data were collected on demographics, comorbidities, social and medical histories, preoperative labs, surgical information, intraoperative data, and postoperative outcomes. The primary outcome was delayed postoperative discharge (length of hospital stay > 7 days). Risk factors for delayed discharge were identified through univariate and multivariate regression analyses, leading to the development of a risk scoring system, the effectiveness of which was evaluated through receiver operating characteristic curve analysis.
Results: 110 patients (74.8%) were discharged within 7 days post-transplant, while 36 (24.7%) remained hospitalized for 8 days or longer. Univariate and multivariate logistic regression analyses identified ABO incompatibility, BUN levels, anesthesia time, and vasodilator use as risk factors for delayed discharge. The RAKT score, incorporating these factors, demonstrated a predictive performance with a C-statistic of 0.789. Conclusions: This study identified risk factors for delayed discharge after RAKT and developed a promising risk scoring system for real-world clinical application, potentially improving postoperative outcome stratification in RAKT recipients
Analysis of Commercial Discrete Event Simulation Packages in a MetaFactory Environment
No full text메타팩토리 환경에서의 상용 이산사건 시뮬레이션 패키지 분석 울산대학교 대학원 산업경영공학과 박지현 빠르게 변화하는 고객의 Needs와 다품종 소량 생산 체계의 생산 방식 변화에 따라 공정의 복잡도가 증대되며 고도화된 생산 공정을 사전에 예측하고 최적화하기 위해 디지털 트윈환경에서 생산 시뮬레이션 기법이 각광받고 있다. Industry 4.0의 초연결 화, 초지능화 된 ICT 기술과 Society 5.0의 인간중심의 가상현실이 함께 발전하고 물 리적 공간인 현실 세계와 가상의 공간인 메타버스 세계가 상호작용하며 가치를 창출 하는 시대로 나아가고 있는 상황이다. 이에 따라 제조업에 메타버스와 디지털 트윈 기술을 빠르게 도입하고 있다. 그러나 메타팩토리 개념이 등장한 초기 단계로 기존의 스마트팩토리 개념 및 기술과 명확하게 구분되지 않고 있다. 또한 디지털 트윈의 발 전과 함께 신규 시뮬레이션 패키지가 빠르게 개발되고 기존 패키지의 기능이 업데이 트됨에 따라 사용자들이 어떤 시뮬레이션 소프트웨어 패키지를 활용하여 개발을 진행 하는지에 대한 의사결정이 어려운 실정이다.
이에 본 연구에서는 3가지 연구 질문과 답변으로 구성하여 연구 결과를 도출하였 다. 실제 문제에 상용 이산사건 시뮬레이션 소프트웨어를 적용해 연구를 진행한 문헌 을 기반으로 주요 소프트웨어를 도출하고 패키지의 각 특성을 분석해 소프트웨어 선 택에 어려움을 겪고 있는 기업과 사용자에게 선택의 기반을 제공한다. 다음으로 스마 트팩토리와 디지털 트윈, 메타팩토리의 개념과 주요 기술을 비교하여 정리해 각 특성 과 차이점을 명확하게 정의하였다. 메타팩토리의 가상공간에 현실과 동일한 공장을 구축하고 시뮬레이션을 통해 효율성과 생산성을 향상하게 되면서 시뮬레이션의 중요 성도 커지고 있다. 이에 따라 본 연구에서는 메타팩토리의 주요 기술 특성을 기반으 로 이산사건 시뮬레이션 소프트웨어의 구현 수준을 평가하여 메타팩토리와의 연계성 을 분석해 추후 메타팩토리를 구축하고 가상 시뮬레이션을 수행하고자 하는 기업 및 사용자에게 기초자료로 사용될 것으로 판단한다.Maste
Does Rheumatoid Arthritis Increase the Risk of COPD?: A Nationwide Retrospective Cohort Study
No full textBackground: Most reports of pulmonary manifestations in rheumatoid arthritis (RA) have been related to interstitial lung diseases. RA and COPD are both chronic inflammatory systemic diseases.
Research question: Does RA increase the risk of developing COPD? Is there a difference between seropositive and seronegative RA in the risk of COPD?
Study design and methods: Using the Korean National Health Insurance Database, we screened individuals diagnosed with RA between 2010 and 2017. We identified 46,030 patients with RA (32,608 with seropositive RA and 13,422 with seronegative RA) and 230,150 matched control individuals; we monitored them until December 2019. We used multivariate Cox proportional hazard models to estimate the adjusted hazard ratio (aHR) of risk factors for the development of COPD.
Results: The incidence of COPD among patients with RA was 5.04 per 1,000 person-years; it was 2.23 per 1,000 person-years in the control group. Patients with RA showed a higher risk of developing COPD (aHR, 2.11; 95% CI, 1.96-2.28) compared with the control group. Although both seropositive RA and seronegative RA were associated with an increased risk of COPD, patients with seropositive RA had a higher risk for the development of COPD (aHR, 1.26; 95% CI, 1.09-1.46) than patients with seronegative RA. In the subgroup analyses, smoking history did not demonstrate significant interactions between RA and COPD development.
Interpretation: RA was shown to be associated with an increased risk of COPD development, augmented by seropositivity. Physicians should monitor respiratory symptoms and pulmonary function carefully in patients with RA
How to Start and Build Microsurgery Practice-Topics on Success and Sustainability: Global/International
No full textMany young microsurgeons begin their careers at established hospitals where microsurgery resources are limited. This article shares the authors’ experiences in overcoming challenges and establishing a microsurgery practice in a new hospital. Due to the lack of equipment, limited support from colleagues, absence of discussion partners, fear of failure, and unpredictable situations, many aspiring microsurgeons lose their motivation. The purpose of this article is to guide future microsurgeons by describing the author’s actions and suggesting improvements for their first free flap case. Key factors for building a successful, sustainable, and enjoyable microsurgery practice include remembering your training and mentors, acquiring fundamental knowledge of microsurgery, creating a supportive ecosystem, and having fun
Incidentally found parotid gland lesion in 18F-FDG PET/CT for staging evaluation of patients with hepatocellular carcinoma: remote possibility of metastatic tumor or second primary salivary gland malignancy
No full textObjectives: We primarily aimed to evaluate whether parotid incidental lesion (PIL) in 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for staging evaluation of patients with hepatocellular carcinoma (HCC) would represent a possibility of extrahepatic metastasis or second primary malignancy (SPM). Additionally, we explored the incidence of PIL in HCC patients and examined any associated risk factors.
Methods: We retrospectively analyzed patients with HCC who underwent 18F-FDG PET/CT at our institution from 2010 to 2022. The pathological findings of PILs in HCC patients were investigated for confirmatory identification of the risk of HCC metastasis or SPM in parotid gland. Healthy controls received 18F-FDG PET/CT for health screening were also enrolled to compare the incidence of PILs with HCC patients. Various parameters associated with patient demographics and characteristics of HCC were analyzed to find the related factors of PILs.
Results: A total of 17,674 patients with HCC and 2,090 healthy individuals who had undergone 18F-FDG PET/CT scans were enrolled in the analyses. Among the 54 HCC patients who underwent pathological confirmation for PILs, benign primary parotid tumor was most commonly observed (n = 43 [79.6%]); however, no malignant lesions were detected, including HCC metastasis. The incidence of PILs was higher in patients diagnosed with HCC compared with the control group (485 [2.7%] vs. 23 [1.1%], p = 0.002). Analysis for the risk factors for PILs revealed that patient age, sex, and positive viral markers were significantly associated with the incidence of PILs in patients with HCC (all p < 0.001).
Conclusions: Our study demonstrates that PILs are more frequently identified in patients with HCC on 18F-FDG PET/CT. However, no malignant PIL, including extrahepatic metastasis of HCC, was identified. Therefore, the presence of PIL should not impede or delay the treatment process for patients with HCC. Additionally, we suggested that for future swift and straightforward differential diagnoses of PIL, the development of additional protocols within the PET/CT imaging could be beneficial
Guiding Intervention for Complex Coronary Lesions by Optical Coherence Tomography or Intravascular Ultrasound
No full textBackground
Optical coherence tomography (OCT) and intravascular ultrasound (IVUS) have shown comparable outcomes in guiding percutaneous coronary intervention (PCI). However, their comparative effectiveness in complex coronary artery lesions remains unclear.
Objectives
This study compared the effectiveness and safety of OCT-guided vs IVUS-guided PCI for complex coronary artery lesions.
Methods
This was a prespecified, main subgroup analysis of complex coronary artery lesions in the OCTIVUS (Optical Coherence Tomography Versus Intravascular Ultrasound Guided Percutaneous Coronary Intervention) trial, which included unprotected left main disease, bifurcation disease, an aorto-ostial lesion, a chronic total occlusion, a severely calcified lesion, an in-stent restenotic lesion, a diffuse long lesion, or multivessel PCI. The primary endpoint was a composite of death from cardiac causes, target vessel-related myocardial infarction, or ischemia-driven target vessel revascularization.
Results
In 2,008 randomized patients, 1,475 (73.5%) underwent imaging-guided PCI for complex coronary artery lesions; 719 (48.7%) received OCT-guided and 756 (51.3%) IVUS-guided PCI. At a median follow-up of 2.0 years, primary endpoint event had occurred in 47 patients (6.5%) in the OCT-guided group and in 56 patients (7.4%) in the IVUS-guided group (HR: 0.87; 95% CI: 0.59-1.29; P = 0.50). These findings were consistent in adjusted analyses. The incidence of contrast-induced nephropathy was similar between the 2 groups (1.9% vs 1.5%; P = 0.46). The incidence of major procedural complications was lower in the OCT-guided group than in the IVUS-guided group (1.7% vs 3.4%; P = 0.03).
Conclusions
Among patients with complex coronary artery lesions, OCT-guided PCI showed a similar risk of primary composite event of death from cardiac causes, target vessel-related myocardial infarction, or target vessel revascularization as compared with IVUS-guided PCI. (Optical Coherence Tomography Versus Intravascular Ultrasound Guided Percutaneous Coronary Intervention [OCTIVUS]; NCT03394079
Increased PD-1 expression of bone marrow T-cells in acute myeloid leukaemia patients after stem cell transplantation, and its association with overall survival
No full textBackground: Immune checkpoints are involved in mechanisms by which tumours escape from the host immune system. Our aim was to evaluate acute myeloid leukaemia (AML) patients to determine expression levels of checkpoint molecules according to diagnosis and treatments, and to identify optimal candidates for checkpoint blockade.
Methods: Bone marrow (BM) samples were obtained from 279 AML patients at different disease status and from 23 controls. Flow cytometric analyses of PD-1 and PD-L1/PD-L2 expression were performed.
Results: Programmed death-1 (PD-1) expression levels on CD8+ T-cells at AML diagnosis were increased compared to controls. PD-L1 and PD-L2 expression levels on leukaemic cells at diagnosis were significantly higher in secondary AML than in de novo AML. PD-1 levels on CD8+ and CD4+ T-cells after allo-SCT were significantly higher than those at diagnosis and after CTx. PD-1 expression on CD8+ T-cells increased in the acute GVHD group than in the non-GVHD group. The overall survival of patients with high PD-1 expression on CD8+ T-cells was significantly shorter than that of patients with low PD-1 expression.
Conclusions: In conclusion, patients who underwent allo-SCT exhibited high PD-1 expression, suggesting that allo-SCT increases PD-1 expression on T-cells, and the patients with high PD-1 expression on CD8+ T-cells after allo-SCT showed the poor prognosis. For these patients, PD-1 blockade could be an immunotherapeutic strategy
Risk Factors for Impaired Cellular or Humoral Immunity after Three Doses of SARS-CoV-2 Vaccine in Healthy and Immunocompromised Individuals
No full textBackground: We aimed to identify the risk factors for impaired cellular and humoral immunity after three doses of the SARS-CoV-2 vaccine. Methods: Six months after the third vaccine dose, T-cell immunity was evaluated using interferon-gamma release assays (IGRAs) in 60 healthy and 139 immunocompromised (IC) individuals, including patients with hematologic malignancy (HM), solid malignancy (SM), rheumatic disease (RD), and kidney transplantation (KT). Neutralizing antibody titers were measured using the plaque reduction neutralization test (PRNT) and surrogate virus neutralization test (sVNT). Results: T-cell immunity results showed that the percentages of IGRA-positive results using wild-type/alpha spike protein (SP) and beta/gamma SP were 85% (51/60) and 75% (45/60), respectively, in healthy individuals and 45.6% (62/136) and 40.4% (55/136), respectively, in IC individuals. IC with SM or KT showed a high percentage of IGRA-negative results. The underlying disease poses a risk for impaired cellular immune response to wild-type SP. The risk was low when all doses were administered as mRNA vaccines. The risk factors for an impaired cellular immune response to beta/gamma SP were underlying disease and monocyte%. In the sVNT using wild-type SP, 12 of 191 (6.3%) individuals tested negative. In the PRNT of 46 random samples, 6 (13%) individuals tested negative for the wild-type virus, and 19 (41.3%) tested negative with omicrons. KT poses a risk for an impaired humoral immune response. Conclusions: Underlying disease poses a risk for impaired cellular immune response after the third dose of the SARS-CoV-2 vaccine; KT poses a risk for impaired humoral immune response, emphasizing the requirement of precautions in patients
Improvement of De-NOx Performance of a SCR System by Dual-Point Ammonia Injection in a Diesel Engine
No full textSelective catalytic reduction (SCR) catalysts is used widely to reduce NOx emissions from diesel engines. However, improvements in de-NOx performance are required to meet future standards of near-zero NOx emissions. This study examines the effectiveness of dual-point NH3injection technology, in which gaseous NH3is injected into both closed coupled and under floor SCR catalysts. The NOx removal efficiency of dual-point NH3injection is compared with that of single-point injection in a World Harmonized Transient Cycle test. The results show that dual-point injection of NH3gas can effectively reduce NOx emissions from diesel engines due to superior temporal and spatial distribution of NH3gas in an SCR catalyst
Association between systemic inflammation biomarkers and mortality in patients with sepsis-associated acute kidney injury receiving intensive care and continuous kidney replacement therapy: results from the RENERGY (REsearches for NEphRology and epidemioloGY) study
No full textBackground: Identifying risk factors and improving prognostication for mortality among patients with sepsis-associated acute kidney injury (AKI) undergoing continuous kidney replacement therapy (CKRT) is important in improving the adverse prognosis of this patient population. This study aimed to compare the prognostic value of existing systemic inflammation biomarkers and determine the optimal systemic inflammation biomarker in patients with sepsis-associated AKI receiving CKRT.
Methods: This multi-center, retrospective, observational cohort study included 1,500 patients with sepsis-associated AKI treated with intensive care and CKRT. The main predictor was a panel of 13 different systemic inflammation biomarkers. The primary outcome was 28-day mortality after CKRT initiation. Secondary outcomes included 90-day mortality after CKRT initiation, CKRT duration, kidney replacement therapy dependence at discharge, and lengths of intensive care unit (ICU) and hospital stays.
Results: When added to the widely accepted Acute Physiology and Chronic Health Evaluation II score, platelet-to-albumin ratio (PAR) and neutrophil-platelet score (NPS) had the highest improvements in prognostication of 28-day mortality, where the corresponding increases in C-statistic were 0.01 (95% confidence interval [CI], 0.00-0.02) and 0.02 (95% CI, 0.01-0.03). Similar findings were observed for 90-day mortality. The 28- and 90-day mortality rates were significantly lower for the higher PAR and NPS quartiles. These associations remained significant even after adjustment for potential confounding variables in multivariable Cox proportional hazards models.
Conclusion: Of the available systemic inflammation biomarkers, the addition of PAR or NPS to conventional ICU prediction models improved the prognostication of patients with sepsis-associated AKI receiving intensive care and CKRT