• Journal of the Korean Society of Radiology
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• v.18 no.3
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• pp.239-248
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• 2024

Radiation therapy uses high energy, which can have side effects on the human body. Therefore, it is important to ensure that the appropriate dose is set for irradiation and to have confidence in the radiation produced by the generator. The EPR/Alanine dosimetry system is characterized by water equivalence, dose response linearity, and low fading, which makes it useful for quality control of radiation therapy equipment. In this study, we compared the signal and dose response curves of EPR/Alanine dosimetry by mass of alanine using 6 MV energy of a LINAC. An alanine dosimeter and EPR spectrometer from Burker, and a LINAC from Elekta, were used. A dose response curve and a 1st order regression equation were constructed from the irradiated dose and the EPR signal from the alanine dosimeter. We compared the signal magnitude and dose response curve with mass and checked the confidence through the measurement uncertainty of the dose response curve. As a result, it was found that the magnitude of the EPR signal increased by about 1.3 times at 64.5 mg, and the sensitivity of the dose response curve increased as the mass increased. The measurement uncertainty was evaluated to be between 5.84 % and 8.93 %. Through this study, it is expected that the EPR/alanine dosimetry system can be applied to the quality assurance and quality control of a LINAC.

• Biomolecules & Therapeutics
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• v.32 no.3
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• pp.349-360
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• 2024

Oxidative stress contributes to the onset of chronic diseases in various organs, including muscles. Morroniside, a type of iridoid glycoside contained in Cornus officinalis, is reported to have advantages as a natural compound that prevents various diseases. However, the question of whether this phytochemical exerts any inhibitory effect against oxidative stress in muscle cells has not been well reported. Therefore, the current study aimed to evaluate whether morroniside can protect against oxidative damage induced by hydrogen peroxide (H₂O₂) in murine C2C12 myoblasts. Our results demonstrate that morroniside pretreatment was able to inhibit cytotoxicity while suppressing H₂O₂-induced DNA damage and apoptosis. Morroniside also significantly improved the antioxidant capacity in H₂O₂-challenged C2C12 cells by blocking the production of cellular reactive oxygen species and mitochondrial superoxide and increasing glutathione production. In addition, H₂O₂-induced mitochondrial damage and endoplasmic reticulum (ER) stress were effectively attenuated by morroniside pretreatment, inhibiting cytoplasmic leakage of cytochrome c and expression of ER stress-related proteins. Furthermore, morroniside neutralized H₂O₂-mediated calcium (Ca²⁺) overload in mitochondria and mitigated the expression of calpains, cytosolic Ca²⁺-dependent proteases. Collectively, these findings demonstrate that morroniside protected against mitochondrial impairment and Ca²⁺-mediated ER stress by minimizing oxidative stress, thereby inhibiting H₂O₂-induced cytotoxicity in C2C12 myoblasts.

• The Journal of the Convergence on Culture Technology
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• v.10 no.4
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• pp.17-22
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• 2024

The war that broke out on October 7, 2023 is prolonging and expanding into the Middle East. Although the damage from war is increasing, humanitarian aid to the Gaza Strip has been halted due to UNRWA's deviant actions. Powerful countries have suspended support, and the UN is appealing for support for the Gaza Strip. All damage is borne by civilians in the Gaza Strip, especially women, children, and the elderly. Israel has selected an evacuation zone and evacuation route in the Gaza Strip and established a humanitarian aid route in the border area. However, Hamas's resistance in underground tunnels, using civilian-dense areas and civilian facilities such as hospitals and schools as shields, further amplified civilian casualties. This Israel-Hamas war requires the international community to approach it from a human security perspective. We must strengthen the UN's functions and roles to ensure that humanitarian supplies reach the field and humanitarian intervention forces ensure human dignity and basic rights. We must restore the credibility of the UN's role through the Israel-Hamas war. In addition, Korea should urge the introduction of humanitarian aid and goods, and provide humanitarian goods such as daily necessities and medicine. We must also prepare for deployment as a member of the UN peacekeeping force in the future. These activities will help Korea develop into a model country that fulfills its role as a 'global pivotal nation' and will have a virtuous cycle of international support in the event of a future crisis on the Korean Peninsula.

• Korean Circulation Journal
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• v.52 no.6
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• pp.429-440
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• 2022

Background and Objectives: Endovascular therapy (EVT) first strategy has been widely adopted for the treatment of chronic limb threatening ischemia (CLTI) patients in real-world practice. This study aimed to investigate long-term outcomes of CLTI patients who underwent EVT and identify prognostic factors. Methods: From the retrospective cohorts of a Korean multicenter endovascular therapy registry, 1,036 patients with CLTI (792 men, 68.8 ± 9.5 years) were included. The primary endpoint was amputation-free survival (AFS) defined as the absence of major amputation or death. Secondary endpoints were major adverse limb events (MALE; a composite of major amputation, minor amputation, and reintervention). Results: Five-year AFS and freedom from MALE were 69.8% and 61%, respectively. After multivariate analysis, age (hazard ratio [HR], 1.476; p<0.001), end-stage renal disease (ESRD; HR, 2.340; p<0.001), Rutherford category (RC) 6 (HR, 1.456; p=0.036), and suboptimal EVT (HR, 1.798; p=0.005) were identified as predictors of major amputation or death, whereas smoking (HR, 0.594; p=0.007) was protective. Low body mass index (HR, 1.505; p=0.046), ESRD (HR, 1.648; p=0.001), femoropopliteal lesion (HR, 1.877; p=0.004), RC-6 (HR, 1.471; p=0.008), and suboptimal EVT (HR, 1.847; p=0.001) were predictors of MALE. The highest hazard rates were observed during the first 6 months for both major amputation or death and MALE. After that, the hazard rate decreased and rose again after 3-4 years. Conclusions: In CLTI patients, long-term outcomes of EVT were acceptable. ESRD, RC-6, and suboptimal EVT were common predictors for poor clinical outcomes.

• Korean Circulation Journal
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• v.52 no.4
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• pp.304-319
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• 2022

Background and Objectives: De-escalation of dual-antiplatelet therapy through dose reduction of prasugrel improved net adverse clinical events (NACEs) after acute coronary syndrome (ACS), mainly through the reduction of bleeding without an increase in ischemic outcomes. Whether the benefits of de-escalation are sustained in highly thrombotic conditions such as ST-elevation myocardial infarction (STEMI) is unknown. We aimed to assess the efficacy and safety of de-escalation therapy in patients with STEMI or non-ST-segment elevation ACS (NSTE-ACS). Methods: This is a pre-specified subgroup analysis of the HOST-REDUCE-POLYTECH-ACS trial. ACS patients were randomized to prasugrel de-escalation (5 mg daily) or conventional dose (10 mg daily) at 1-month post-percutaneous coronary intervention. The primary endpoint was a NACE, defined as a composite of all-cause death, non-fatal myocardial infarction, stent thrombosis, clinically driven revascularization, stroke, and bleeding events of grade ≥2 Bleeding Academic Research Consortium (BARC) criteria at 1 year. Results: Among 2,338 patients included in the randomization, 326 patients were diagnosed with STEMI. In patients with NSTE-ACS, the risk of the primary endpoint was significantly reduced with de-escalation (hazard ratio [HR], 0.65; 95% confidence interval [CI], 0.48-0.89; p=0.006 for de-escalation vs. conventional), mainly driven by a reduced bleeding. However, in those with STEMI, there was no difference in the occurrence of the primary outcome (HR, 1.04; 95% CI, 0.48-2.26; p=0.915; p for interaction=0.271). Conclusions: Prasugrel dose de-escalation reduced the rate of NACE and bleeding, without increasing the rate of ischemic events in NSTE-ACS patients but not in STEMI patients.

• The Korean journal of internal medicine
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• v.39 no.3
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• pp.501-512
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• 2024

Background/Aims: Optimal risk stratification based on simplified geriatric assessment to predict treatment-related toxicity and survival needs to be clarified in older patients with diffuse large B-cell lymphoma (DLBCL). Methods: This multicenter prospective cohort study enrolled newly diagnosed patients with DLBCL (≥ 65 yr) between September 2015 and April 2018. A simplified geriatric assessment was performed at baseline using Activities of Daily Living (ADL), Instrumental ADL (IADL), and Charlson's Comorbidity Index (CCI). The primary endpoint was event-free survival (EFS). Results: The study included 249 patients, the median age was 74 years (range, 65-88), and 125 (50.2%) were female. In multivariable Cox analysis, ADL, IADL, CCI, and age were independent factors for EFS; an integrated geriatric score was derived and the patients stratified into three geriatric categories: fit (n = 162, 65.1%), intermediate-fit (n = 25, 10.0%), and frail (n = 62, 24.9%). The established geriatric model was significantly associated with EFS (fit vs. intermediate-fit, HR 2.61, p < 0.001; fit vs. frail, HR 4.61, p < 0.001) and outperformed each covariate alone or in combination. In 87 intermediate-fit or frail patients, the relative doxorubicin dose intensity (RDDI) ≥ 62.4% was significantly associated with worse EFS (HR, 2.15, 95% CI 1.30-3.53, p = 0.002). It was related with a higher incidence of grade ≥ 3 symptomatic non-hematologic toxicities (63.2% vs. 27.8%, p < 0.001) and earlier treatment discontinuation (34.5% vs. 8.0%, p < 0.001) in patients with RDDI ≥ 62.4% than in those with RDDI < 62.4%. Conclusions: This model integrating simplified geriatric assessment can risk-stratify older patients with DLBCL and identify those who are highly vulnerable to standard dose-intensity chemoimmunotherapy.

• Korean Circulation Journal
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• v.52 no.7
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• pp.529-540
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• 2022

Background and Objectives: Limited data are available regarding long-term clinical outcomes of iliac artery endovascular therapy (EVT) in real-world practice. This study investigated long-term outcomes according to Trans-Atlantic Inter-Society Consensus (TASC) classifications. Methods: We analyzed data from 1,705 limbs of 1,364 patients from the retrospective cohort of the multicenter Korean Vascular Intervention Society Endovascular Therapy in Lower Limb Artery Disease registry. The primary endpoint was target lesion revascularization (TLR)-free survival. Results: TASC A, B, C, and D lesions were present in 19.4%, 26.2%, 28.7%, and 25.7% of the treated limbs, respectively. The technical success rate was 96.2% and did not differ between TASC lesion types. Complications occurred in 6.8% of cases and more occurred in TASC D (11.8%). Iliac artery EVT showed a 5-year TLR-free survival of 89.2%. The TASC D group had the lowest TLR-free rate of 79.3%. TASC D (hazard ratio [HR], 1.75; 95% confidence interval [CI], 1.12-2.73; p=0.014), plain old balloon angioplasty (HR, 4.25; 95% CI, 2.03-8.88; p<0.001), current smoker (HR, 1.89; 95% CI, 1.26-2.83; p=0.002), previous bypass surgery (HR, 3.04; 95% CI, 1.28-7.19; p=0.011), combined femoropopliteal treatment (HR, 4.89; 95% CI, 3.19-7.50; p<0.001), combined below the knee treatment (HR, 2.20; 95% CI, 1.25-3.89; p=0.007), and complications (HR, 1.86; 95% CI, 1.07-3.24; p=0.028) were predictors for TLR. Conclusions: Iliac artery EVT achieved excellent technical success and 5-year TLR-free survival. TASC D showed a favorable but lower 5-year TLR-free survival rate and higher complication rate compared with other TASC groups.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.26 no.2
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• pp.141-151
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• 2024

Objective: Double microcatheter technique (dMC) can be the alternative to Single microcatheter technique (sMC) for challenging cases, but there is lack of studies comparing dMC to sMC especifically for small ruptured aneurysms. Our objective was to compare the safety and efficacy of dMC to sMC in treating small (≤5 mm) and tiny (≤3 mm) ruptured aneurysms. Methods: This study focused on 91 out of 280 patients who had ruptured aneurysms and underwent either single or double microcatheter coil embolization. These patients were treated with either single or double microcatheter coil embolization. We divided the patients into two groups based on the procedural method and evaluated clinical features and outcomes. Subgroup analyses were conducted specifically for tiny aneurysms, comparing the two methods, and within the dMC group, we also examined whether the aneurysm was tiny or not. In addition, univariate logistic regression analysis was performed to assess the impact of coil packing density. Results: The mean values for most outcome measures in the dMC group were higher than those in the sMC group, but these differences did not reach statistical significance (coil packing density, 45.739% vs. 39.943%; procedural complication, 4.17% vs. 11.94%; recanalization, 8.3% vs. 10.45%; discharge discharge modified Rankin Scale (mRS), 1.83 vs. 1.97). The comparison between tiny aneurysms and other sizes within the dMC group did not reveal any significant differences in terms of worse outcomes or increased risk. The only factor that significantly influenced coil packing density in the univariate logistic regression analysis was the size of the aneurysm (OR 0.309, 95% CI 0.169-0.566, p=0.000). Conclusions: The dMC proved to be a safe and viable alternative to the sMC for treating small ruptured aneurysms in challenging cases.

• International Journal of Stem Cells
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• v.15 no.2
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• pp.203-216
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• 2022

Background and Objectives: Epidemiological investigations have shown positive correlations between increased diesel exhaust particles (DEP) in ambient air and adverse health outcomes. DEP are the major constituent of particulate atmospheric pollution and have been shown to induce proinflammatory responses both in the lung and systemically. Here, we report the effects of DEP exposure on the properties of human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs), including stemness, regeneration, and immunomodulation. Methods and Results: Non-apoptotic concentrations of DEP (10 ㎍/ml) inhibited the migration and osteogenic differentiation capacity of WJ-MSCs. Gene expression profiling showed that DEP increased intracellular reactive oxygen species (ROS) and expression of pro-inflammatory and metabolic-process-related genes including cFos. Furthermore, WJ-MSCs cultured with DEP showed impaired suppression of T cell proliferation that was reversed by inhibition of ROS or knockdown of cFos. ERK inhibition assay revealed that DEP-induced ROS regulated cFos through activation of ERK but not NF-κB signaling. Overall, low concentrations of DEP (10 ㎍/ml) significantly suppressed the stemness and immunomodulatory properties of WJ-MSCs through ROS/ERK/cFos signaling pathways. Furthermore, WJ-MSCs cultured with DEP impaired the therapeutic effect of WJ-MSCs in experimental colitis mice, but was partly reversed by inhibition of ROS. Conclusions: Taken together, these results indicate that exposure to DEP enhances the expression of pro-inflammatory cytokines and immune responses through a mechanism involving the ROS/ERK/cFos pathway in WJ-MSCs, and that DEP-induced ROS damage impairs the therapeutic effect of WJ-MSCs in colitis. Our results suggest that modulation of ROS/ERK/cFos signaling pathways in WJ-MSCs might be a novel therapeutic strategy for DEP-induced diseases.

• The Journal of the Convergence on Culture Technology
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• v.10 no.5
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• pp.195-200
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• 2024

The purpose of this study is to propose optimized cognitive warfare strategies for the Korean Peninsula by analyzing recent war case studies. Through the analysis of the Armenia-Azerbaijan war, the Israel-Palestine conflict, the Ukraine-Russia war, and the Israel-Hamas conflict, it was found that the following aspects are crucial in conducting cognitive warfare: 1) applying methods according to objectives, 2) organizing and structuring appropriately to the objectives and means, and 3) utilizing various means from both civilian and military sectors. Based on these findings, cognitive warfare strategies optimized for the operational environment of the Korean Peninsula were suggested in terms of the three elements of military innovation. From the aspect of methodology, it is recommended to develop cognitive warfare scenarios based on legitimacy and legality, and to integrate roles according to the level of warfare. Regarding organization and structuring, the establishment of a national-level control tower and the construction of an integrated response system involving civilians, government, military, and police based on legislation are proposed. In terms of means, it is suggested to utilize various tools from the civilian, government, military, and police sectors, such as North Korean defectors, psychological warfare broadcasts against North Korea, social media, and cyber operations, for auditory, visual, and message delivery. In future battlefields characterized by hyper-connectivity and hyper-intelligence, the execution of cognitive warfare will become increasingly important. Therefore, it is necessary to continuously develop optimized cognitive warfare strategies for the Korean Peninsula through comprehensive national efforts.