Publications by authors named "Yeochan Yun"

With the applications of in situ X-ray diffraction (XRD), electrical - measurement, and ambient pressure hard X-ray photoelectron spectroscopy (AP-HAXPES), the characteristics of the topotactic phase transition of LaCoO (LCO) thin films are examined. XRD measurements show clear evidence of structural phase transition (SPT) of the LCO thin films from the perovskite (PV) LaCoO to the brownmillerite (BM) LaCoO phases through the intermediate LaCoO phase at a temperature of 350 °C under high-vacuum conditions, ∼10 mbar. The reverse SPT from BM to PV phases is also found under ambient pressure (>100 mbar) of air near 100 °C.

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Nanomaterial properties such as size, structure, and composition can be controlled by manipulating radiation, such as gamma rays, X-rays, and electron beams. This control allows scientists to create materials with desired properties that can be used in a wide range of applications, from electronics to medicine. This use of radiation for nanotechnology is revolutionizing the way we design and manufacture materials.

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Transition metal nitrides have extensive applications, including magnetic storage devices, hardware resistance coatings, and low-temperature fuel cells. This study investigated the structural, electrical, and mechanical properties of thin zirconium nitride (ZrN) films by examining the effects of laser irradiation times. Thin ZrN films were deposited on glass substrates using pulsed DC magnetron sputtering and irradiated with a diode laser for 6 and 10 min.

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Background/objectives: The acute stress response affects brain metabolites closely linked to the tricarboxylic acid (TCA) cycle. This response involves time-dependent changes in hormones and neurotransmitters, which contribute to resilience and the ability to adapt to acute stress while maintaining homeostasis. This physiological mechanism of metabolic dynamics, combined with time-series analysis, has prompted the development of new methods to observe the relationship between TCA cycle-related brain metabolites.

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Manganese is one of the trace elements necessary for organisms to maintain normal biological activities and is also a cofactor for manganese superoxide dismutase (Mn-SOD) and manganese peroxidase (MnP). In order to find a simple and effective method to rejuvenate the degenerated strains, we explored the effect of the exogenous addition of MnSO on the antioxidant vigour and productivity of degenerated strains of . The results showed that the exogenous MnSO had no significant effect on the non-degenerated strain T0, but it could effectively increase the mycelial growth rate, mycelial biomass, and LBL decolouring ability of the degenerated strains T10 and T19, and reduce the production cycle and increased the biological efficiency of T10; it helped the severely degenerated T19 to regrow its fruiting body; and it also significantly increased the viability of the matrix-degrading enzymes such as EG, Lac, Xyl, etc.

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Purpose: TP53 mutations are common in head and neck squamous cell carcinoma (HNSCC). We evaluated their clinical impact in patients treated with targeted agents or immunotherapy in the KCSG HN15-16 TRIUMPH trial.

Materials And Methods: We analyzed clinical characteristics and outcomes of patients with TP53 mutations in the TRIUMPH trial, a multicenter, biomarker-driven umbrella trial in Korea.

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The immune system continuously interacts with tumors, possibly leading to systemic alterations in circulating immune cells. However, the potential of these cancer-associated changes for diagnostic purposes remains poorly explored. To investigate this, we conducted a comprehensive flow cytometric analysis of 452 peripheral blood mononuclear cell (PBMC) samples from 206 non-small-cell lung cancer (NSCLC) patients, 100 small-cell lung cancer (SCLC) patients, 94 healthy individuals, and 52 benign lung disease (BLD) patients.

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Background: Seizures can cause as well as result from neuroinflammation. This study was performed to identify the hematologic inflammatory parameters (HIPs) and inflammatory mediators that change after a single seizure in a canine pentylenetetrazole (PTZ)-induced seizure model.

Methods: Five healthy Beagle dogs were used in this study.

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The 3-chymotrypsin-like protease (3CL-PR; also known as Main protease) of SARS-CoV-2 is a cysteine protease that is the target of the COVID-19 drug, Paxlovid. Here, we report for 3CL-PR, the pH-rate profiles of a substrate, an inhibitor, affinity agents, and solvent kinetic isotope effects (sKIEs) obtained under both steady-state and pre-steady-state conditions. "Bell-shaped" plots of log( / ) vs pH for the substrate (Abz)SAVLQ*SGFRK(Dnp)-NH and p vs pH for a peptide aldehyde inhibitor demonstrated that essential acidic and basic groups of p = 8.

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This study aimed to evaluate red pepper powder quality by the extent of chilling injury and develop a method for detecting chilling injury-affected pepper powder. Pepper powder produced from chilling injury-affected pepper fruits exhibited increased bitter amino acids, microbial counts, and biogenic amines and decreased sweetness index and organic acid levels. These quality deteriorations indicate the need to detect chilling injury in pepper powders.

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Methylergometrine has widely been used pharmacologically to treat conditions such as pain, addiction, vasoconstriction, migraines, and Parkinson's disease. Despite its side effects, it is used as a therapeutic agent and research material for various diseases based on its natural potential; however, the regulatory effect of its interaction with the nicotinic acetylcholine receptor (nAChR) has not yet been investigated. The α3β4 nAChR is an ion channel essential for neurotransmission within the sympathetic, parasympathetic, and autonomic nervous systems.

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Mesenchymal stem cells (MSCs) are promising candidates for regenerative therapies due to their self-renewal and differentiation capabilities. Pathological microenvironments expose MSCs to senescence-inducing factors such as reactive oxygen species (ROS), resulting in MSC functional decline and loss of stemness. Oxidative stress leads to mitochondrial dysfunction, a hallmark of senescence, and is prevalent in aging tissues characterized by elevated ROS levels.

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Purpose: Data collection in community organizations can be challenging, but important for evaluative initiatives as well as for therapeutic purposes, such as for organizations engaged in measurement-based care. This study tested the impact of an online measurement data management platform (OMDMP) on mental health assessment response rates at a community-based sexual assault crisis center. We examined whether implementing the OMDMP improved client assessment participation in mental health assessment questionnaires compared to manual data collection methods.

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Microbial inoculants offer an environmentally friendly approach to enhance plant growth and control disease. In this study, two strains, HKSSLJEBR3 (R3) and Ya-1 were isolated from pepper plant roots and tropical rainforest soil, respectively. Both strains exhibited strong antifungal activity against f.

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Objective: Cognitive impairment occurs throughout the entire course of and affects the work and life of patients with major depressive disorder (MDD). The gut microbiota, kynurenine pathway (KP) and inflammatory response may have important roles in the mechanism of cognitive impairment in MDD patients. Consequently, our goal was to investigate the association among the gut microbiota, inflammation, KP, and cognition in MDD.

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Alzheimer's disease (AD), the most prevalent degenerative brain disease associated with dementia, requires early diagnosis to alleviate worsening of symptoms through appropriate management and treatment. Recent studies on AD stage classification are increasingly using multimodal data. However, few studies have applied graph neural networks to multimodal data comprising F-18 florbetaben (FBB) amyloid brain positron emission tomography (PET) images and clinical indicators.

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β-lactams have been the most successful antibiotics, but the rise of multi-drug resistant (MDR) bacteria threatens their effectiveness. Serine β-lactamases (SBLs), among the most common causes of resistance, are classified as A, C, and D, with numerous variants complicating structural and substrate spectrum comparisons. This study compares representative SBLs of these classes, focusing on the substrate-binding pocket (SBP).

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Ritonavir (RTV) is a potent CYP3A inhibitor that is widely used as a pharmacokinetic (PK) enhancer to increase exposure to select protease inhibitors. However, as a strong and complex perpetrator of CYP3A interactions, RTV can also enhance the exposure of other co-administered CYP3A substrates, potentially causing toxicity. Therefore, the prediction of drug-drug interactions (DDIs) and estimation of dosing requirements for concomitantly administered drugs is imperative.

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Lipoteichoic acid (LTA) and peptidoglycan (PGN) are considered as key virulence factors of , which is a representative sepsis-causing Gram-positive pathogen. However, cooperative effect of LTA and PGN on nitric oxide (NO) production is still unclear despite the pivotal roles of NO in initiation and progression of sepsis. We here evaluated the cooperative effects of LTA (SaLTA) and muramyl dipeptide (MDP), the minimal structure of PGN, on NO production in both a mouse macrophage-like cell line, RAW 264.

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Double-bundle (DB) anterior cruciate ligament (ACL) reconstruction has biomechanical advantages over single-bundle reconstruction. However, most studies perform the DB reconstruction with 2 femoral tunnels, which fails to provide an entire femoral footprint for ACL reconstruction. In this study, we describe a femoral double-bundle footprint technique for ACL reconstruction, named the tendon groove technique.

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Salvia miltiorrhiza, the anticancer properties of these components are multifaceted, encompassing the inhibition of tumor growth, prevention of the metastatic spread of cancer cells, enhancement of the sensitivity of cancer cells to chemotherapy and radiation therapy, and the suppression of angiogenesis, which is crucial for tumor growth and survival. In the context of our recent study, we have discovered that tanshinone I, one of the active components of Salvia miltiorrhiza, possesses the ability to inhibit the proliferation of ovarian cancer cells, both in laboratory settings and within living organisms. To further understand the molecular mechanisms behind this effect, we conducted a comprehensive transcriptomic analysis.

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Spermiogenesis is an indispensable process occurring during the later stages of spermatogenesis. Despite multiple proteins being associated with spermiogenesis, the molecular mechanisms that control spermiogenesis remain poorly characterized. In this study, we show that 1700030J22RIK is exclusively expressed in the testis of mice and investigate its roles in spermiogenesis using genetic and proteomic approaches.

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Introduction: Patients with cancer experience physical, mental, and social pain that affects themselves and their families. The increasing cancer incidence and advances in treatment have increased the number of cancer survivors in Korea, and there is an influx of patients in Seoul and other metropolitan areas, leading to shortages of continuous care and comprehensive life support facilities. Patients must travel long distances for treatment, which poses logistical and quality-of-life challenges.

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Objective: To investigate the changes in bile acid (BA) metabolites within the follicular fluid (FF) of patients with diminished ovarian reserve (DOR) and to identify novel diagnostic markers that could facilitate early detection and intervention in DOR patients.

Design: A total of 182 patients undergoing assisted reproductive technology (ART) were enrolled and categorized into the normal ovarian reserve (NOR) group (n = 91) or the DOR group (n = 91) to measure BA levels in FF. To identify the changes in granulosa cells (GCs), we collected GCs from an additional 7 groups of patients for transcriptome sequencing.

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