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Safety and effectiveness of tofacitinib in Korean adult patients with ulcerative colitis: post-marketing surveillance study
No full textBackground: Tofacitinib is an oral Janus kinase inhibitor for the treatment of ulcerative colitis (UC). We aimed to identify the safety and effectiveness of tofacitinib in patients with UC in routine clinical settings in Korea.
Methods: This open-label, observational, prospective, post-marketing surveillance study was conducted at 22 hospitals in the Republic of Korea. Patients with moderate to severe active UC who received tofacitinib were included and followed up for up to 52 weeks. Tofacitinib was administered at a dosage of 10 mg twice daily for at least 8 weeks, followed by 5 or 10 mg twice daily at the investigator's discretion based on clinical evaluation according to the approved Korean label. Safety including adverse events (AEs) and effectiveness including clinical remission, clinical response, and endoscopic mucosal healing were evaluated. Safety analysis set was defined as all patients registered for this study who received at least one dose of tofacitinib according to the approved Korean label and followed up for safety data. Effectiveness analysis set included patients in the safety analysis set who were evaluated for overall effectiveness assessment and excluded patients who had received tofacitinib less than 8 weeks.
Results: A total of 110 patients were enrolled, of whom 106 patients were included in the safety population. The median duration of treatment was 370 days and the treatment duration ranged from 16 to 684 days for the safety population. AEs occurred in 42 patients (39.6%). Serious AEs (SAEs) occurred in 7 patients (6.6%) and of them, there were 2 cases of serious infections. These serious infections were reported as Adverse Event of Special Interest (AESI) in this study and no other AESI were reported. There were no cases of death during the study period. Clinical remission rates were 40.0%, 46.7%, 57.6%, and 55.1% at 8, 16, 24, and 52 weeks, and clinical response rates were 77.8%, 87.9%, 56.6%, and 81.4% at each visit, respectively. Endoscopic mucosal healing rates were 58.7% at 16 weeks and 46.2% at 52 weeks.
Conclusion: Tofacitinib was effective in Korean patients with moderate to severe active UC and the safety findings were consistent with the known safety profile of tofacitinib. This study confirmed the safety and effectiveness of tofacitinib in Korean patients with moderate to severe active UC in routine clinical settings.
Trial registration: This study is registered in the ClinicalTrials.gov under the identifier NCT04071405, registered on 28 August 2019
Association of preoperative sarcopenia with the long-term prognosis of patients with bladder cancer undergoing radical cystectomy
No full textPurpose: This retrospective study aimed to assess the correlation between preoperative sarcopenia and long-term oncologic outcomes in patients undergoing radical cystectomy for bladder cancer.
Methods: We included 528 patients who underwent radical cystectomy for bladder cancer between 2000 and 2010 at Asan Medical Center, Seoul, Korea. Preoperative skeletal muscle mass was quantified by analyzing computed tomography images at the third lumbar vertebra. Sarcopenia was defined based on the skeletal muscle index. We evaluated various clinical and pathological factors to analyze the association between sarcopenia and long-term oncologic outcomes.
Results: The median follow-up time was 104 months. Sarcopenia was identified in 37.9% of the patients. Although no significant differences were observed in traditional pathological factors between the sarcopenic and non-sarcopenic groups, sarcopenia was significantly associated with worse oncologic outcomes. Compared to the non-sarcopenic groups, the sarcopenic group had lower overall survival rates (52.0% vs. 67.1% at 5 years, 35.5% vs. 52.7% at 10 years) and higher cancer-specific mortality (63.3% vs. 74.3% at 5 years, 50.7% vs. 67.4% at 10 years). Multivariable Cox regression analysis demonstrated that sarcopenia was an independent predictor of cancer-specific survival (hazard ratio: 1.49, 95% confidence interval: 1.11-2.01, p = 0.008), alongside body mass index, tumor stage, lymph node metastasis, and lymphovascular invasion.
Conclusion: Sarcopenia was significantly associated with poor cancer-specific survival in patients undergoing radical cystectomy for bladder cancer. Detecting sarcopenia may assist in preoperative risk stratification and long-term management after radical cystectomy
The Effect of Cognitive Affordance Elements on the User's Immersion in Virtual Space
No full text(연구배경 및 목적) 가상현실(VR)과 증강현실(AR) 기술의 발전은 다양한 산업에서 혁신을 이끌고 있으며, 특히 몰입형 콘텐츠의 발전에 중점을 두고 있다. 몰입감은 가상공간에서 사용자가 현실감을 느끼고 외부 세계와 단절되는 상태로, 교육, 의료, 게임 등 여러 분야에서 중요한 역할을 한다. 이를 높이기 위해 시청각적 요소와 인지적 어포던스가 중요한데, 인지적 어포던스는 사용자가 가상 환경에서 직관적으로 상호작용을할 수 있도록 돕는 설계 요소이다. 본 연구는 인지적 어포던스가 사용자 몰입감에 미치는 영향을 탐구하여, 가상공간 디자인의 이론적 기반을 강화하고 다양한 산업에서의 실무적 적용 가능성을 높이는 것을 목적으로 한다. (연구 방법) 첫째, 선행 연구를 통해 가상공간의 인지적 어포던스와 사용자 몰입감의 정의 및 연관성을 분석하였다. 둘째, 이론적 고찰과 선행 논문을 바탕으로 설문 문항을 작성하고 신뢰성과 타당성을 검증하기 위해 VR/AR/3D 그래픽 분야의 5년 이상 경력을 가진 전문가들로 구성된 포커스 그룹 인터뷰(FGI)를 실시하였다. 셋째, 가상공간에 대한 이해가 높은 20~40대 남녀 32명을 대상으로 설문조사를 진행했습니다. 참가자들은 인지적 어포던스가 높은 '폴리나토르 공원'과 낮은 '베오그라드 국립박물관 VR 전시'를 체험한 후 설문에 응답하였다. 수집된 데이터는 SPSS를 사용해 분석되었으며, 이를 통해 가상공간에서 인지적 어포던스 요소가 사용자 몰입감에 미치는 영향을 실증적으로 검토하였다. (결과) 본 연구는 가상공간에서 인지적 어포던스가 사용자 몰입감에 미치는 영향을 분석하기 위해 지각성, 사용용이성, 정보성, 몰입성의 네 가지 요소를 중심으로 설문 문항을 작성하여 실증적으로 고찰하였다. 독립 T검정 결과, 폴리나토르 공원을 체험한 A 그룹과 베오그라드 국립 박물관 VR 전시를 체험한 B 그룹 간의 사용자 몰입감 평균에 통계적으로 유의미한 차이가 있음을 확인했다(p < 0.05). 따라서, A 그룹이 체험한 콘텐츠가 B 그룹보다 사용자 몰입감을 더 효과적으로 증진시켰으며, 귀무가설(H?)은 기각되고 대립가설(H₁)이 채택되었다. (결론) 종합적으로, 가상공간에서 몰입감을 향상하기 위해서는 실제와 같은 그래픽만으로는 한계가 있으며, 인지적 어포던스 요소들이 조화를 이룰 때 사용자 몰입도가 더 높아진다는 결론을 도출하였다. 표본 수의 제한으로 결과를 일반화하는 데 한계가 있지만, 이 연구는 가상공간 콘텐츠 설계에 유용한 가이드라인을 제공하며, 향후 VR 콘텐츠 제작에 실질적인 참고 자료로 활용될 수 있을 것으로 기대한다.
(Background and Purpose) Advancements in Virtual Reality (VR) and Augmented Reality (AR) technologies have driven innovation across various industries, particularly in the development of immersive content. Immersion is the state in which users feel a sense of reality and detachment from the external world within a virtual space. It plays a crucial role in fields, such as education, healthcare, and gaming. Audiovisual and cognitive affordances are essential to enhance immersion. Cognitive affordances are design elements that enable users to interact intuitively with virtual environments. This study explores the impact of cognitive affordances on user immersion to strengthen the theoretical foundation of virtual environment design and increase its practical applicability across various industries. (Method) Previous studies were reviewed to analyze the definitions of and relationship between cognitive affordances in virtual environments and user immersion. Based on theoretical considerations and prior research, survey questions were developed, and their reliability and validity were verified through a focus group interview (FGI) with experts with over five years of experience in VR/AR/3D graphics. Subsequently, a survey was conducted with 32 men and women aged 20?40 years with a high understanding of virtual environments. The participants experienced both Pollinator Park, which had high cognitive affordances, and the Belgrade National Museum VR Exhibition, which had low cognitive affordances, and responded to the survey. The collected data were analyzed using SPSS; the impact of cognitive affordances on user immersion in virtual environments was empirically examined. (Results) This study empirically examined the impact of cognitive affordances on user immersion in virtual environments by developing survey questions based on four key factors, namely perception, usability, informativeness, and immersiveness. The results of the independent t-test revealed a statistically significant difference in the average user immersion between Group A, which experienced the Pollinator Park, and Group B, which experienced the Belgrade National Museum VR Exhibition (p < 0.05). The content experienced by Group A more effectively enhanced user immersion compared to that of Group B, leading to the rejection of the null hypothesis (H?) and the establishment of the alternative hypothesis (H₁). (Conclusions) Enhancing immersion in virtual environments cannot be achieved solely through realistic graphics. Rather, a higher level of user immersion is attained when cognitive affordance elements are well integrated. Although the sample size limits the generalizability of the results, this study provides useful guidelines for designing virtual environment content and is expected to serve as a practical reference for future VR content development
Surgical Outcomes in Non-Small Cell Lung Cancer with Distant Metastasis: The Prognostic Significance of Delayed Metastasis Diagnosis
No full textBackground: The diagnosis of distant metastasis on preoperative examinations for non-small cell lung cancer (NSCLC) can be challenging, leading to surgery for some patients with uncertain metastasis. This study evaluated the prognostic impact of delayed diagnosis of metastasis on patients who underwent upfront surgery.
Methods: The study enrolled patients who underwent lobectomy or pneumonectomy for NSCLC between June 2010 and December 2017 and evaluated the presence of distant metastasis before surgery. Overall survival (OS) for patients with stage IV cancer was compared with that for patients without metastasis, and the prognostic factors were analyzed.
Results: Of 3046 patients (mean age, 63 years; 1770 men), 100 (3.3 %) had distant metastasis, diagnosed preoperatively in 1.4 % (42/3046) and postoperatively in 1.9 % (58/3046) of the patients. The two most common metastasis sites diagnosed after surgery were contralateral lung (22/58, 37.9 %) and ipsilateral pleura (16/58, 27.6 %). The OS (median, 42.7 months) for the patients with stage IV cancer diagnosed postoperatively was comparable with that for the patients with stage IIIB cancer (P = 0.865), whereas the OS (median OS, 91.7 months) for the patients with stage IV cancer diagnosed preoperatively was better than for the patients with stage IIIB cancer (P = 0.001). Among the patients with distant metastasis, squamous cell type (hazard ratio [HR], 3.15; P = 0.002) and systemic treatment for metastasis (HR, 2.42; P = 0.002) were independent predictors of worse OS.
Conclusions: Among NSCLC patients undergoing upfront surgery, the OS for the patients with stage IV cancer diagnosed postoperatively was comparable with that for the patients with stage IIIB cancer. For patients with stage IV disease, squamous cell type and systemic treatment for metastasis were prognostic factors for poorer OS
Impact of Drug-Coated Balloon-Based Revascularization in Patients with Chronic Total Occlusions
No full textBackground: Percutaneous coronary intervention (PCI) with a drug-eluting stent (DES) for chronic total coronary occlusions (CTOs) improves clinical symptoms and quality of life. However, data on drug-coated balloon (DCB)-based PCI in CTO lesions are limited. Methods: A total of 200 patients were successfully treated for CTO lesions, either with DCB alone or in combination with DES (DCB-based PCI). They were compared with 661 patients who underwent second-generation DES implantation for CTO from the PTRG-DES registry (DES-only PCI). The endpoint was major adverse cardiovascular events (MACEs), which included a composite of cardiac death, myocardial infarction, stent or target lesion thrombosis, target vessel revascularization, and major bleeding at 2 years. Results: In the DCB-based PCI group, 49.0% of patients were treated with DCB only and 51.0% underwent the hybrid approach combining DCB with DES. Bailout stenting was performed in seven patients (3.5%). The DCB-based PCI group exhibited fewer stents (1.0; IQR: 0.0-1.0 and 2.0; IQR: 1.0-3.0, p < 0.001), shorter stent lengths (6.5 mm; IQR: 0.0-38.0 mm and 42.0 mm; IQR: 28.0-67.0 mm, p < 0.001), and lower usage of small stents with a diameter of 2.5 mm or less (9.8% and 36.5%, p < 0.001). Moreover, the DCB-based PCI group had a lower rate of MACEs than the DES-only PCI group (3.1% and 13.2%, p = 0.001) at 2-year follow-up. Conclusions: The DCB-based PCI approach significantly reduced the stent burden, particularly in the usage of small stent diameters, and resulted in a lower risk of MACEs compared to DES-only PCI in CTO lesions
Giant anisotropy of magnetic damping in an epitaxial Cr/Fe bilayer with the absence of magnetocrystalline anisotropy
No full textMagnetic damping is one of the most important parameters governing the critical current density for current-induced magnetization switching in spin-torque devices. The anisotropic nature of magnetic damping, influenced by both intrinsic and extrinsic factors, has been demonstrated in both theoretical and experimental studies. Nevertheless, understanding the underlying mechanisms of magnetic damping anisotropy, particularly in the bilayer structure of a ferromagnet and a nonmagnetic metal, remains an open challenge. In this study, we investigate the crystallographic dependence of magnetic damping in an epitaxial Cr/Fe bilayer, which has negligible magnetocrystalline anisotropy. We experimentally extracted the total damping by conducting frequency-dependent ferromagnetic resonance measurement at different in-plane angles. The observed damping reveals a strong angular dependence with an anisotropy of ∼400% in the bilayer. All possible contributions to the total damping will be discussed carefully to clarify the origin of the profound damping anisotropy observed in our Cr/Fe bilayer
Prevalence, clinical features, and survival outcome trends of 627 patients with primary cutaneous lymphoma over 29 years: a retrospective review from single tertiary center in Korea
No full textThe relative frequency of primary cutaneous lymphoma (PCL) subtypes shows wide variation across different geographical regions. This retrospective study was conducted in a tertiary referral center located in Korea to describe the relative frequency, demographics, survival outcomes, and temporal trend in PCL. A total of 627 PCL cases diagnosed between January 1994 and December 2022 were included. The majority of PCL cases (87.2%) were of T-/NK-cell lineage (CTCL), while the remaining cases (12.8%) were B-cell lineage lymphomas (CBCL). The prevalence of mycosis fungoides (MF) in CTCL increased significantly over time, while other CTCL subtypes, including primary cutaneous extranodal NK/T-cell lymphoma and subcutaneous panniculitis-like T-cell lymphoma (SPTCL), decreased in frequency. Notably, the prevalence of CD4-positive small/medium T-cell lymphoproliferative disorder showed a substantial increase over time. Primary cutaneous marginal zone lymphoma was consistently the commonest CBCL subtype. Survival analysis demonstrated that CTCL had a more favorable 5-year overall survival (OS) than CBCL. OS rate of MF, SPTCL, and primary cutaneous peripheral T-cell lymphoma, NOS improved significantly over time. This study provides comprehensive insights into the dynamic change in the relative frequency and overall survival of PCL subtypes over time
Divarasib plus cetuximab in KRAS G12C-positive colorectal cancer: a phase 1b trial
No full textKRAS G12C mutation is prevalent in ~4% of colorectal cancer (CRC) and is associated with poor prognosis. Divarasib, a KRAS G12C inhibitor, has shown modest activity as a single agent in KRAS G12C-positive CRC at 400 mg. Epidermal growth factor receptor has been recognized as a major upstream activator of RAS-MAPK signaling, a proposed key mechanism of resistance to KRAS G12C inhibition in CRC. Here, we report on divarasib plus cetuximab (epidermal growth factor receptor inhibitor) in patients with KRAS G12C-positive CRC (n = 29) from arm C of an ongoing phase 1b trial. The primary objective was to evaluate safety. Secondary objectives included preliminary antitumor activity. The safety profle of this combination was consistent with those of single-agent divarasib and cetuximab. Treatment-related adverse events led to divarasib dose reductions in four patients (13.8%); there were no treatment withdrawals. The objective response rate was 62.5% (95% confdence interval: 40.6%, 81.2%) in KRAS G12C inhibitor-naive patients (n = 24). The median duration of response was 6.9 months. The median progression-free survival was 8.1 months (95% confdence interval: 5.5, 12.3). As an exploratory objective, we observed a decline in KRAS G12C variant allele frequency associated with response and identifed acquired genomic alterations at disease progression that may be associated with resistance. The manageable safety profle and encouraging antitumor activity of divarasib plus cetuximab support the further investigation of this combination in KRAS G12C-positive CRC
Dynamic Risk Model for the Medical Treatment of Graves' Hyperthyroidism according to Treatment Duration
No full textBackgruound: Changes in thyrotropin receptor antibody (TRAb) levels are associated with the clinical outcomes of Graves' hyperthyroidism. However, the effects of the patterns of TRAb changes on patient prognosis according to the treatment duration of antithyroid drugs (ATDs) are not well established.
Methods: In this retrospective cohort study, 1,235 patients with Graves' hyperthyroidism who were treated with ATDs for more than 12 months were included. Patients were divided into two groups according to treatment duration: group 1 (12-24 months) and group 2 (>24 months). Risk prediction models comprising age, sex, and either TRAb levels at ATD withdrawal (model A) or patterns of TRAb changes (model B) were compared.
Results: The median treatment duration in groups 1 (n=667, 54%) and 2 (n=568, 46%) was 17.3 and 37.1 months, respectively. The recurrence rate was significantly higher in group 2 (47.9%) than in group 1 (41.4%, P=0.025). Group 2 had significantly more goiter, thyroid eye disease, and fluctuating and smoldering type of TRAb pattern compared with group 1 (all P<0.001). The patterns of TRAb changes were an independent risk factor for recurrence after adjusting for other confounding factors in all patients, except in group 1. Integrated discrimination improvement and net reclassification improvement analyses showed that model B performed better than model A in all patients, except in group 1.
Conclusion: The dynamic risk model, including the patterns of TRAb changes, was more suitable for predicting prognosis in patients with Graves' hyperthyroidism who underwent longer ATD treatment duration
Synthesis of Functionalized Boron Nitride Decorated on Erbium Vanadate (ErVO4) Composite for Electrochemical Detection of Nitrofurazone in Environmental Samples
No full textThe present strategy introduces a novel hydrothermal method to develop a rod-like highly crystalline zircon-type erbium vanadate (ErVO4) structure combined with spherical shaped functionalized boron nitride (F-BN), forming a ErVO4/F-BN heterostructure, through the sonochemical method. The resultant heterostructure composite was characterized using different spectroscopic techniques, and the composite was fabricated on a screen-printed carbon paste electrode (SPCE) for the electrochemical sensing of nitrofurazone. Further electrochemical characteristic analyses including cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry were performed to analyze the electrocatalytic reduction mechanism of NFN. Fascinatingly, the modified SPCE with the ErVO4/F-BN heterostructure displayed a broad and dynamic linear range of 0.001 to 306 μM with a limit of detection of 0.49 nM and sensitivity of 21.178 μA·μM-1·cm-2 for electrochemical reduction sensing of nitrofurazone. The ErVO4/F-BN electrode also displayed superior selectivity with a 5-fold variation toward different interfering compounds and delivered excellent stability, reproducibility, and practical analysis in real water samples, suggesting the feasibility of practical application as an electrochemical sensor for antibiotics