Publications by authors named "Byoung Choul Kim"

Immune checkpoint blockade (ICB) has become a standard anti-cancer treatment, offering durable clinical benefits. However, the limited response rate of ICB necessitates biomarkers to predict and modulate the efficacy of the therapy. The gut microbiome's influence on ICB efficacy is of particular interest due to its modifiability through various interventions.

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  • Myh1 is identified as a mouse gene linked to deafness, with its role in the auditory system still unclear; knockout mice show significant hearing impairment and abnormal hair cell function.
  • Research shows that MYH1 variants in humans contribute to non-progressive hearing loss, with some individuals also experiencing osteopenia.
  • Structural and functional analysis indicates that MYH1 variants disrupt regular activity in outer hair cells, highlighting the gene's essential role in hearing and its genetic connection to hearing loss in affected families.
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Type 2 innate lymphoid cells (ILC2s) have emerged as key regulators of the immune response in renal inflammatory diseases such as lupus nephritis. However, the mechanisms underlying ILC2 adhesion and migration in the kidney remain poorly understood. Here, we revealed the critical role of integrin α4β7 in mediating renal ILC2 adhesion and function.

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  • Sonodynamic therapy (SDT) offers a noninvasive way to target deep tumors using ultrasound and special sonosensitizers, but the process faces challenges due to sonosensitizers' low stability and poor uptake in cells.
  • This study explores the use of non-ionic polysorbate (Tween 80, T80) to create micelles that enhance the delivery of a mitochondria-targeting sonosensitizer (T-Ce6) combined with a pro-oxidant (piperlongumine, PL) for better treatment effectiveness.
  • The T80 micelles significantly improved the internalization of T-Ce6, leading to increased production of reactive oxygen species in cancer cells and triggering cancer-specific
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Nonthermal biocompatible plasma (NBP) is a promising option for improving medication absorption into the human skin. Currently, most plasma devices for cosmetics employ a floating-electrode plasma source for treating the skin. Human skin serves as the ground electrode in the floating-electrode plasma discharge, and discharge occurs between the skin and electrodes of the device.

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Extracellular vesicles (EVs) are becoming increasingly important in liquid biopsy for cancer because they contain multiple biomarkers, including proteins and RNAs, and circulate throughout the body. Cancer cell-derived EVs are highly heterogeneous, and multiplexed biomarker detection techniques are required to improve the accuracy of diagnosis. In addition, in situ EV biomarker detection increases the efficiency of the detection process because EVs are difficult to handle.

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Cancer metastasis is affected by chemical factors and physical cues. From cell adhesion to migration, mechanical tension applied to integrin expresses on the cell membrane and physical confinement significantly regulates cancer cell behaviors. Despite the physical interplay between integrins in cells and ligands in the tumor microenvironment, quantitative analysis of integrin tension during cancer cell migration in microconfined spaces remains elusive owing to the limited experimental tools.

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  • * Using a single molecule pull down (SiMPull) assay, researchers found that APP molecules prefer to form homo-dimers over hetero-dimers, especially in APP751 due to the KPI domain's presence.
  • * Further analysis with computational models revealed that the KPI domain has stronger attractive interactions with itself compared to other domains, leading to a greater tendency for APP751 to form homo-dimers than APP695.
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The presence of senescent cells within tissues has been functionally linked to malignant transformations. Here, using tension-gauge tethers technology, particle-tracking microrheology, and quantitative microscopy, we demonstrate that senescent-associated secretory phenotype (SASP) derived from senescent fibroblasts impose nuclear lobulations and volume shrinkage on malignant cells, which stems from the loss of RhoA/ROCK/myosin II-based cortical tension. This loss in cytoskeletal tension induces decreased cellular contractility, adhesion, and increased mechanical compliance.

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  • Physical interactions between cells and their surrounding extracellular matrix (ECM) can affect cell behavior, impacting conditions like cancer invasion and metastasis.
  • The research introduces a new tool called the "topo-tension gauge tether (TGT)" to measure the force on integrin-ligand bonds in response to different nanopatterns.
  • The study highlights how this tool helps visualize and quantify the tension in integrins, offering insights into how cells adapt to their environment and how this relates to their adhesion and morphology.
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Sonodynamic therapy, which utilizes ultrasound (US) to produce cytotoxic reactive oxygen species (ROS), can overcome the critical drawbacks of photodynamic therapy, such as limited tissue penetration depth. However, the development of sonosensitizers having superior sonodynamic effects and desirable biocompatibility remains a major challenge. In this study, nanoscale zirconium-based porphyrinic metal organic frameworks (MOFs) (PCN-222) were developed as safe and effective nanosonosensitizers.

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Mechanical response to external stimuli is a conserved feature of many cell types. For example, neurotransmitters (e.g.

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Secondary infections typically worsen outcomes of patients recovering from septic shock. Neutrophil [polymorphonuclear leukocytes (PMNs)] migration to secondarily inoculated sites may play a key role in inhibiting progression from local bacterial inoculation to secondary infection. Mitochondrial -formyl peptide (mtFP) occupancy of formyl peptide receptor-1 (FPR1) has been shown to suppress PMN chemotaxis.

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Our incomplete understanding of osteoarthritis (OA) pathogenesis has significantly hindered the development of disease-modifying therapy. The functional relationship between subchondral bone (SB) and articular cartilage (AC) is unclear. Here, we found that the changes of SB architecture altered the distribution of mechanical stress on AC.

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Background: Gene silencing using siRNA can be a new potent strategy to treat many incurable diseases at the genetic level, including cancer and viral infections. Treatments using siRNA essentially requires an efficient and safe method of delivering siRNA into cells while maintaining its stability. Thus, we designed novel synergistic fusion peptides, i.

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In this study, we investigated the biophysical interaction between cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and CD80. CTLA-4 is a key molecule in immunosuppression, and CD80 is a costimulatory receptor promoting T cell activation. We observed that after cell-cell contact was established between breast cancer cells and antigen presenting cells (APCs), CTLA-4 expressed on the breast cancer cells bind to CD80 expressed on the APCs, and underwent trans-endocytosis to deplete CD80.

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Urinary tract infection (UTI) is one of the most common bacterial infections in infants less than age 1 year. UTIs frequently recur and result in long-term effects include sepsis and renal scarring. Uropathogenic Escherichia coli (UPEC), the most prevalent organism found in UTIs, can cause host inflammation via various virulence factors including hemolysin and cytotoxic necrotizing factors by inducing inflammatory cytokines such as interleukin (IL)-1β.

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  • Human embryonic stem cells showed quick and permanent movement of NANOG and OCT4 from the nucleus to the cytoplasm after just 30 minutes of stretching, while Sox2 remained unchanged.
  • The movement was driven by biophysical signals relayed from cell surface integrins to the nuclear transport mechanism, without the influence of outside factors.
  • When using E-CADHERIN-coated surfaces, even with limited integrin interaction, stretching still caused all three transcription factors to move quickly from the nucleus to the cytoplasm, suggesting important implications for understanding early development and bioengineering in stem cell research.
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Here we report exquisitely distinct material properties of primary vascular smooth muscle (VSM) cells isolated from the thoracic aorta of adult (8 months) vs. aged (30 months) F344XBN rats. Individual VSM cells derived from the aged animals showed a tense internal network of the actin cytoskeleton (CSK), exhibiting increased stiffness (elastic) and frictional (loss) moduli than those derived from the adult animals over a wide frequency range of the imposed oscillatory deformation.

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One proposed mechanism of cellular aging is the gradual loss of certain cellular components that are insufficiently renewed. In an earlier study, multidrug resistance transporters (MDRs) were postulated to be such aging determinants during the yeast replicative life span (RLS). Aged MDR proteins were asymmetrically retained by the aging mother cell and did not diffuse freely into the bud, whereas newly synthesized MDR proteins were thought to be deposited mostly in the bud before cytokinesis.

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Notch receptor activation initiates cell fate decisions and is distinctive in its reliance on mechanical force and protein glycosylation. The 2.5-angstrom-resolution crystal structure of the extracellular interacting region of Notch1 complexed with an engineered, high-affinity variant of Jagged1 (Jag1) reveals a binding interface that extends ~120 angstroms along five consecutive domains of each protein.

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This paper uses computer simulations to reveal unprecedented details about linearization of deoxyribonucleic acid (DNA) inside dynamic nanochannels that can be repeatedly widened and narrowed. We first analyze the effect of rate of channel narrowing on DNA linearization dynamics. Quick (∼0.

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  • Notch signaling is crucial for development and tissue maintenance and is activated at cell-cell interfaces through ligand-receptor interactions that are influenced by mechanical forces.
  • The study introduces a new low tension gauge tether (LTGT) to measure the single molecular force required for activation of the Notch receptor, utilizing DNA interactions with a binding protein.
  • Results show that Notch activation requires forces between 4 and 12 piconewtons, establishing a connection between mechanical forces and Notch signaling activation.
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This paper describes a simple technique for patterning channels on elastomeric substrates, at two distinct scales of depth, through the use of controlled fracture. Control of channel depth is achieved by the careful use of different layers of PDMS, where the thickness and material properties of each layer, as well as the position of the layers relative to one another, dictate the depth of the channels formed. The system created in this work consists of a single 'deep' channel, whose width can be adjusted between the micron- and the nano-scale by the controlled application or removal of a uniaxial strain, and an array of 'shallow' nano-scale channels oriented perpendicular to the 'deep' channel.

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