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Treatment outcomes for idiopathic sudden sensorineural hearing loss in dialysis patients
No full textIdiopathic sudden sensorineural hearing loss (ISSNHL) is challenging for both nephrologists and otolaryngologists treating patients undergoing dialysis. This single-center, retrospective, observational study investigated the treatment outcomes of patients with ISSNHL undergoing dialysis, enrolling 700 patients (47 undergoing and 653 not undergoing dialysis) diagnosed with ISSNHL between January 2005 and December 2021 at Asan Medical Center, Republic of Korea. To balance pre-existing clinical characteristics, 1:5 propensity score matching (PSM) was performed with the patients who were not undergoing dialysis. Treatment included high-dose systemic steroid therapy or intra-tympanic steroid injections. The pure tone average of the groups was compared before and 2 weeks and 2 months after treatment. The hearing-improvement degree was evaluated using Siegel's criteria. Before PSM, age, prevalence of diabetes or hypertension, initial hearing threshold at each frequency level (0.5, 1, 2, and 4 kHz), and treatment strategies exhibited significant between-group differences. However, in the PS-matched cohort, none of the confounders showed significant between-group differences. Two months after steroid treatment, the non-dialysis patient group demonstrated significantly higher average improvement in pure tone audiometry (P = 0.029) and greater percentage of complete response according to Siegel's criteria. This study suggests that treatment outcomes for ISSNHL are significantly poorer for patients undergoing than for those not undergoing dialysis
A nationwide real-world study for evaluation of effectiveness and safety of T-DM1 in patients with HER2-positive metastatic breast cancer in Korea (KCSG BR19-15)
No full textPurpose: This study aimed to investigate clinical practices and factors related to the outcomes of T-DM1 use in patients with HER2-positive metastatic breast cancer (mBC).
Methods: We included patients with HER2-positive mBC who received T-DM1 as a palliative therapy between August 2017 and December 2018. The safety and outcomes of T-DM1, including overall response rate (ORR), progression-free survival (PFS), and overall survival (OS), were evaluated. A Cox proportional hazards model was used to estimate the hazard ratio and 95% confidence interval (CI) for mortality or progression to HER2-positive mBC.
Results: In total, 824 patients were enrolled during the study period. The mean age of patients was 58 years, and 516 (62.6%) patients relapsed after curative treatment. Excluding a history of endocrine therapy, 341 (41.4%) patients previously received none or first-line chemotherapy, 179 (21.7%) received second-line therapy, and 303 (36.9%) received third-or later-line chemotherapy before T-DM1 therapy. During a median follow-up of 16.8 months, the ORR was 35%, the median PFS was 6.6 months, and the median OS was not reached. The clinical factors associated with the hazard of progression were age (<65 years), poor performance status (⩾2), advanced line of palliative chemotherapy (⩾2), prior pertuzumab use, and treatment duration of palliative trastuzumab (<10 months). Common grade 3-4 adverse events were thrombocytopenia (n = 107, 13.2%), neutropenia (n = 23, 2.8%), anemia (n = 21, 2.6%), and elevated liver enzyme (n = 20, 2.5%). Hypokalemia (⩽3.0 mmol/L) and any-grade bleeding events occurred in 25 (3.1%) and 94 (22.6%) patients, respectively.
Conclusion: This is the first nationwide real-world study of T-DM1 use in patients with HER2-positive mBC in Korea. The effectiveness and toxicity profiles of T-DM1 in real-world practice were comparable to those in randomized trials. Moreover, patient factors and previous anti-HER2 therapy could predict the outcomes of T-DM1 therapy
Mini-access ascending aorto-bifemoral bypass surgery for the treatment of aortic steno-occlusive disease
No full textObjectives: Mid-aortic syndrome is a rare condition characterized by severe aortic narrowing, leading to high upper body blood pressure and organ hypoperfusion, necessitating surgical intervention. Although central bypassing is considered ideal, it involves extensive incisions. To overcome these limitations, less-invasive approaches have been developed. This study aims to introduce a mini-access approach using video-endoscopy and to evaluate the feasibility and outcomes of mini-access ascending aorto-bifemoral bypass surgery.
Methods: From November 2020 to May 2022, we performed ascending aorta to bifemoral artery bypass operations on 7 patients to treat steno-occlusive diseases in the downstream aorta. A Y-graft was created, and procedures were conducted under general anesthesia using video-endoscopy with limited skin incisions.
Results: Intraoperatively, there were no major complications, and none of the patients required cardiopulmonary bypass support. Furthermore, there were no postoperative mortalities or major complications. Postoperatively, the mean ankle-brachial index significantly improved from 0.59/0.59 to 0.96/0.92 (P = .004), and the mean glomerular filtration rate increased from 61.1 to 85.3 mL/min/1.73 mm2 (P = .012). Additionally, symptoms of claudication resolved in all patients.
Conclusions: Videoscope-assisted mini-access aortic bypass surgery not only provides favorable early postoperative outcomes but also represents a technically feasible alternative to traditional surgical approaches for the treatment of steno-occlusive aortic diseases
Task Offloading and Resource Allocation in UAV-Aided Emergency Response Operations via Soft Actor Critic
No full textIn modern emergency responses, unmanned aerial vehicles (UAVs) play a crucial role in redefining disaster management through diverse task execution (e.g., object detection). However, UAVs are usually resource-constrained. To address this issue, UAV mother-ships with edge servers (UMECs) can be placed near UAV scouts for remote task processing. UMECs can have a larger scale of energy consumption and battery capacity than UAV scouts. Therefore, minimizing the total or maximum energy consumption may result in ignoring the energy consumption in UAV scouts and focusing on UMECs, consequently reducing the network’s lifetime. Furthermore, UMECs might lack the capacity to process all types of tasks owing to memory or software restrictions, and faster task execution often necessitates both central processing unit (CPU) and graphics processing unit (GPU), which are rarely considered by existing works. Therefore, this paper studies a task offloading and resource (computation capacity and power) allocation (TORA) problem with the goal of minimizing the maximum energy consumption ratio among UMECs and UAV scouts alongside task execution latency ratio and total energy consumption, where tasks are executed using both CPU and GPU, each UMEC can execute a specific set of tasks, and devices have limited resources. We then formulate the problem as a non-convex mixed-integer nonlinear programming problem and decompose it into multiple sub-problems. Finally, a soft-actor-critic (SAC) based TORA algorithm (SATORA) is proposed to address the problem, which can adapt to the time-varying environment scenario. Numerical simulation results show that SATORA outperforms other baseline algorithms
Transparent Waterborne Polyurethane Composite Reinforced with Cocoon Silk Nanofibers
No full text본 연구에서는 친환경 및 우수한 생분해성과 기계적 특성 등의 장점을 가지는 실크를 유기용매 사용 없이 ACC를 도입하여 물리적 방법으로만 실크의 나노섬유화를 진행하였다. ACC 처리 후 실크 나노섬유의 직경이 139 nm로 나노섬유화가 된 것을 알 수 있다. 이렇게 제조한 실크 나노섬유를 수분산 폴리우레탄에 필러로 도입함으로써 취약점인 기계적 물성을 개선하고자 하였다. 실크 나노섬유를 1.0~5.0 wt%의 비율로 수분산 폴리우레탄과 복합화를 진행 후, Free standing 필름을 제조하여 기계적 특성을 확인하고 투과도를 측정하였다. 실크 나노섬유를 필러로 도입하였을 때 기계적 물성의 경우, 연신율은 감소하나 인장강도, 인성이 증가하여 WPU/SNF 2.5%에서 높은 기계적 물성 개선 효과가 있음을 확인할 수 있었다. 그러나, 실크 나노섬유의 첨가 비율이 증가할수록 투과도가 감소하였다. 실크 나노섬유가 1.0% 첨가되었을 때 투과도가 66.95%로 확인할 수 있다. 기계적 특성과 광학적 특성을 고려하였을 때, 순수한 WPU에서 SNF를 1.0% 첨가하였을 때, 기계적 물성이 좋고 투명한 실크 수분산 폴리우레탄 복합소재를 얻을 수 있다.
In this study, we report on the synthesis of an optically transparent, mechanically robust, water-based polyurethane (WPU) with excellent physical properties and nanocomposites containing silk nanofibers (SNFs) as reinforcing fillers. We use an anionic WPU synthesized poly(tetrahydrofuran) (PTMEG), isophorone diisocyanate (IPDI) and dimethyl propionic acid (DMPA) as internal emulsifiers. Aqueous colloidal suspensions of SNFs are prepared using a top-down physical nanofibrillation system based on: Aqueous counter collision (ACC). Different treatment time and number of ACC processing are tested as processing variables explore optimal conditions that allow high nanofibrillation efficiency for SNFs. SEM analyses showed that the size and diameter of the SNF effectively decrease as the number of ACC passes increased. Finally, mixing the two water-based materials (WPU and SNF) produces a homogeneous WPU/SNF. SNF (1-5 wt%) nanocomposites that simultaneously achieves enhanced mechanical toughness and optical transparency
A study on ways to recycle aged bottom-fixed offshore wind substructures into artificial reefs and the effects
No full text본 연구는 노후화된 고정식 해상풍력 하부구조물 및 해양 플랫폼의 해체 후 인공어초로의 재활용 방안을 검토하고 및 그에 따른 인공어초의 증설·활성화로 인해 촉진되는 환경적, 경제적, 사회적 효과 등을 종합적 으로 고찰하기 위해 수행되었다. 전 세계는 2020년을 시작으로 COVID-19라는 강력하고 암울했던 팬데믹을 보냈지만, 세계 경제는 2022년 중반부터 서서히 그리고 힘겹게 재개되면서 에너지 수요도 차츰 반등되었다. 이에 따라, 온실가스 감축 및 기후변화 적응과 관련한 2016 년 파리협정 이후, 2022년에는 우리정부도 ‘2050 탄소중립 선언’을 발표 하며 풍력 및 태양광을 바탕으로 하는 신재생에너지를 통한 전력 공급을 통해 저탄소화를 계획하는 등의 신재생에너지의 중요성을 점차 확대시켜 나아가고 있으며, 특히, 해상풍력 발전의 비중은 가파르게 성장할 것으로 전망되고 있다. 현재, 국내에서 상용 운전중인 해상풍력 발전단지는 제주 탐라 해상풍력, 전남 영광 해상풍력 그리고 서남해 해상풍력 발전단지가 있으며, 이미 건설 중이거나 신규 개발을 위해 사업 타당성 조사를 마친 곳이 대략 40단지 이상을 웃돌고 있다. 이에, 빠르면 향후 15년 내 노후 화되어 해체시기에 돌입하는 해상풍력 발전단지도 상당히 생겨나게 될 것으로 전망된다. 한편, 20세기 중반부터 글로벌 환경문제 중 하나로 부각된 전통적인 해양 플랫폼의 폐기와 해체에 투입되는 기술적, 사회적 비용을 절감하면 서 ‘자원의 순환적 활용’을 달성하기 위해 노후화된 해양 플랫폼의 재활 용 방안이 다양하게 논의되었다. 그간에 주로 논의된 재활용 방안은 해 양 관광 자원으로의 재활용, 외해 양식장으로의 재개발, 연안 양식용 구 조물인 인공어초로의 재활용 등이었는데, 이 중에서도 다방면으로 높은 효용성 및 실효성이 예측된 동시에, 지속 가능한 방안으로 주목된 것이 인공어초로의 재활용이었다. 이에, 본 연구는 노후화된 고정식 해상풍력 하부구조물 및 해양 플랫 폼의 해체 후 인공어초로의 재활용으로 인한 인공어초 증설과 활성화를 전제로, 인공어초 재활용의 환경적, 경제적, 사회적 효과를 문헌 고찰을 통해 분석함으로써, 노후화된 해양 자원 또는 해양 산업 폐기물의 ‘지속 가능한 순환적 활용’에 도움이 되는 실무적, 산업적 시사점을 도출하였 다. 본 연구의 고찰 결과를 정리해 보면 다음과 같다. 첫째, 노후화된 해상풍력 하부구조물 및 해양 플랫폼의 해체 후 인공 어초로의 재활용은 수중·해양 환경 보호, 인공어초 시설 지역을 중심으 로 수중 생물의 종(種) 다양성과 위집도 증가, 평균 생체량 증가, 시설 해역의 생태계 복원과 개선, 인공어초에 위집된 수초·해조류의 블루 카 본 기능으로 인한 탄소 저감 효과 등 다양하고도 중요한 환경적 효과를 창출한다는 사실을 파악하였고, 이를 통해, 인공어초로의 재활용은 ‘자원 의 순환적 활용’, ‘지속 가능한 양식업’, ‘자연 기반 해법’의 탄소 절감 솔 루션 등에 두루 기여하는 사실을 확인하였다. 이런 고찰 결과를 토대로, 노후화된 해상풍력 하부구조물 및 해양 플랫폼의 해체 후 인공어초로의 재활용 프로세스의 친환경적 기법 개발과 상용화, 시설된 인공어초의 지 속 가능한 활용과 관리를 위한 자연 기반 해법 강화(블루 카본 등 미래 지향적 기능의 집중 육성), 첨단 스마트·인공지능 양식 기술 접목 등 창 의적, 진보적 솔루션을 지속적으로 개발하고 축적해야 할 것이다. 둘째, 노후화된 해상풍력 하부구조물 및 해양 플랫폼의 해체 후 인공 어초로의 재활용은 시설 해역의 어획량 증가, 연안 해역의 어업 생산성 과 수산 자원 증가 등 바람직한 경제적 효과를 창출하는 것으로 파악되 었다. 이런 효과에 주목하면서, 1980년대 이래로 꾸준히 감소·쇠퇴하고 있는 국내 어업의 경쟁력과 불안정성을 해소·완화할 수 있는 미래적 대 안 중 하나로 인공어초의 활용도를 높이는 방안을 지속적으로 강구하고 모색해야 할 것이다. 셋째, 인공어초로의 재활용은 해양 리조트, 다이빙 플랫폼, 수중 생물 체험 플랫폼 등 해상 관광 자원 및 인프라 활성화에 기여하는 동시에, 불법 조업 예방을 통한 해양 주권 보호에도 기여하는 등 의미 있는 사회 적 효과까지 함께 창출하는 것으로 분석되었다. 이에 주목하면서, 인공어 초를 매개로 국내 해양 문화와 해양 자원의 사회적, 교육적 활용도를 높 일 수 있는 방안과 참신한 아이디어를 지속적으로 발굴할 필요가 있을 것이다. 주제어 : 고정식 해상풍력 하부구조물, 해양 플랫폼, 해체, 인공어초, . 지속 가능한 재활용, 탄소 저감, 자연 기반 해법Maste
Evaluating the performance of thermoplastic 3D bolus used in radiation therapy
No full textA 3D-printed bolus is being developed to deliver accurate doses to superficial cancers. In this study, flexible thermoplastic filaments, specifically PLA, TPU, PETG, and HIPS, were fabricated into boluses and then compared to commercial bolus for the variation of the dose elevation region of photon beams. The experimental results indicate that the maximum dose depth is similar, and the consistent trend of the percentage depth dose confirms the potential usage as a build-up bolus
Multimodal Golden DNA Superstructures (GDSs) for Highly Efficient Photothermal Immunotherapy
No full textA-templated metallization has emerged as an efficientstrategy for creating nanoscale-metal DNA hybrid structures with adesirable conformation and function. Despite the potential of DNA-metal hybrids, their use as combinatory therapeutic agents has rarelybeen examined. Herein, we present a simple approach for fabricating amultipurpose DNA superstructure that serves as an efficient photo-immunotherapy agent. Specifically, we adsorb and locally concentrateAu ions onto DNA superstructures through induced local reduction,resulting in the formation of Au nanoclusters. The mechanical andoptical properties of these metallic nanoclusters can be rationallycontrolled by their conformations and metal ions. The resulting goldenDNA superstructures (GDSs) exhibit significant photothermal effectsthat induce cancer cell apoptosis. When sequence-specific immunosti-mulatory effects of DNA are combined, GDSs provide a synergistic effect to eradicate cancer and inhibit metastasis,demonstrating potential as a combinatory therapeutic agent for tumor treatment. Altogether, the DNA superstructure-templated metal casting system offers promising materials for future biomedical applications
Deep RL-based Ellipsoidal Path Planning for MEC enabled UAVs to Minimize Data Transmission Latency and Energy Consumption of Mobile Devices
No full textDue to the flexible deployment and movement capability, unmanned aerial vehicles (UAVs) are being utilized as flying mobile edge computing (MEC) platforms, offering real-time computational resources and low-latency data processing for a wide range of applications. The aim of this article is to explore a multi-UAV-assisted MEC system where multiple UAVs move using ellipsoidal trajectory to provide MEC services to resource-constrained mobile devices in temporary hotspot areas such as festival areas that have delay-sensitive applications with varying task offloading requests. Depending on the position, size, shape, and orientation of the ellipsoidal trajectories, the coverage area, energy consumption of mobile devices, and task transmission latency changes. Moreover, the varying user densities and task offloading request rates make the problem more challenging. Thus, we formulate an optimization problem that finds the center position, major radius, minor radius, and rotation angle of the ellipsoidal trajectory of UAV-assisted MEC servers with the objective of minimizing transmission latency and energy consumption of mobile devices while taking into account the required data transmission rate, task transmission time, energy consumption and several system-related constraints. Then, we have transformed this optimization problem into a Markov decision process and propose a deep Q-learning-based ellipsoidal trajectory optimization (DETO) algorithm to resolve it. The results from our simulations demonstrate that our approach outperforms other baselines, particularly in terms of reducing latency and the energy required for mobile devices to transmit data.Maste
Sex-based outcomes on unguided de-escalation from ticagrelor to clopidogrel in stabilized patients with acute myocardial infarction undergoing percutaneous coronary intervention: a post-hoc analysis of the TALOS-AMI
No full textBackground: The TALOS-AMI study highlighted the effectiveness of a de-escalation strategy shifting from ticagrelor to clopidogrel 1 month after percutaneous coronary intervention (PCI), resulting in significant reduction in clinical events, primarily attributed to a substantial decrease in bleeding events. Nevertheless, the impact of this strategy on outcomes based on sex remains unclear.
Methods: This was a post-hoc analysis of the TALOS-AMI study. At 1 month after PCI, patients who remained adherent to aspirin and ticagrelor without experiencing major adverse events were randomized into either the de-escalation group (clopidogrel plus aspirin) or the active control group (ticagrelor plus aspirin) for an additional 12 months. The primary endpoint encompassed a composite of cardiovascular death, myocardial infarction, stroke, and Bleeding Academic Research Consortium bleeding type 2 or greater at 12 months after randomization.
Results: Among the 2,697 patients included in this study, 454 (16.8%) were women. Women, characterized by older age and a higher prevalence of hypertension, diabetes, impaired renal function, and non-ST-segment myocardial infarction, exhibited a lower primary endpoint at 12 months compared to men [adjusted hazards ratio (HR), 0.60; 95% confidence interval (CI), 0.37-0.95; P = 0.03]. Compare to the active control group, the de-escalation group demonstrated a reduced risk of the primary endpoint in both women (adjusted HR, 0.38; 95% CI, 0.15-0.95; P = 0.039) and men (adjusted HR, 0.56; 95% CI, 0.40-0.79; P = 0.001) (interaction P = 0.46).
Conclusions: In stabilized patients post-PCI with drug-eluting stents for acute myocardial infarction, the primary endpoint was lower among women compared to men. In this cohort, the benefits of an unguided de-escalation strategy from ticagrelor to clopidogrel were comparable in women and men