Publications by authors named "Paik M"

Three new depsipeptides, homiamides A-C (-), were isolated from a marine sediment-derived strain of sp., ROA-065. The planar structures of homiamides A-C (-) were elucidated using mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopic data.

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Background: The KITENIN/ErbB4 complex has been reported to participate in metastasis, which is the principal reason of death in most colorectal cancer patients.

Purpose: New therapeutics need to be developed to suppress the malignant effects of the KITENIN/ErbB4 complex, which is related to drug resistance. The present study aimed to evaluate changes in cancer cell invasion capacity, transcriptional regulators, and cellular bioenergetics after targeting the KITENIN/ErbB4 complex with emodin.

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  • Maternal nutrition during pregnancy has a significant impact on the long-term health of offspring, with potential links to various diseases later in life.
  • The study examined the metabolite profiles of male rat offspring resulting from maternal under- and overnutrition compared to a control group, focusing on changes in their plasma metabolites at 16 weeks old.
  • Key findings revealed that certain fatty acids related to tryptophan and linoleic acid metabolism were altered in the offspring, suggesting that these changes may increase the risk of metabolic and neurodegenerative diseases tied to their mothers' diets during pregnancy.
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  • Bovine digital dermatitis (BDD) is an infection in cattle that leads to hoof lesions and lameness, primarily driven by treponemes as the main pathogens.
  • A study utilizing gas chromatography-mass spectrometry and high-performance liquid chromatography identified significant metabolic changes in organic acids, amino acids, and fatty acids between the pathogens involved.
  • Key findings included drastic reductions in certain metabolites like pyruvic acid and glycine, and notable increases in butyric and propionic acids, indicating complex metabolic interactions that may influence the progression of BDD and enhance understanding of its pathogenesis.
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Background: Aging is a progressive process characterized by weakness in brain function. Although metabolomics studies on the brain related with aging have been conducted, it is not yet fully understood. A systematic metabolomics study was performed to search for biomarkers and monitor altered metabolism in various brain tissues of the cortex, cerebellum, hypothalamus, and hippocampus of young (8 months old) and old rats (22 months old).

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Background: Fabry disease (FD) is an X-linked lysosomal disorder caused by α-galactosidase A enzyme activity deficiency. Although glycosphingolipid analogs have been identified in the plasma or urine of patients with FD, there is a limited understanding of altered metabolomics profiles beyond the globotriaosylceramide accumulation in FD.

Methods: Metabolomics study was performed for monitoring of biomarker and altered metabolism related with disease progression in serum and urine from male α-galactosidase A knockout mice and age-matched wild-type mice at 20 and 40 weeks.

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Background: Expression of the KITENIN/ErbB4 oncogenic complex is associated with metastasis of colorectal cancer to distant organs and lymph nodes and is linked with poor prognosis and poor survival.

Methods: Here, we used in vitro and in silico methods to test the ability of chrysophanol, a molecule of natural origin, to suppress the progression of colorectal cancer by targeting the KITENIN/ErbB4 complex.

Results: Chrysophanol binds to ErbB4, disrupting the ErbB4/KITENIN complex and causing autophagic degradation of KITENIN.

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Collagen hydrolysis, catalyzed by Zn(II)-dependent matrix metalloproteinases (MMPs), is a critical physiological process. Despite previous computational investigations into the catalytic mechanisms of MMP-mediated collagenolysis, a significant knowledge gap in understanding remains regarding the influence of conformational sampling and entropic contributions at physiological temperature on enzymatic collagenolysis. In our comprehensive multilevel computational study, employing quantum mechanics/molecular mechanics (QM/MM) metadynamics (MetD) simulations, we aimed to bridge this gap and provide valuable insights into the catalytic mechanism of MMP-1.

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Aspartyl/asparaginyl hydroxylase (AspH) catalyzes the post-translational hydroxylations of vital human proteins, playing an essential role in maintaining their biological functions. Single-point mutations in the Second Coordination Sphere (SCS) and long-range (LR) residues of AspH have been linked to pathological conditions such as the ophthalmologic condition Traboulsi syndrome and chronic kidney disease (CKD). Although the clinical impacts of these mutations are established, there is a critical knowledge gap regarding their specific atomistic effects on the catalytic mechanism of AspH.

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  • - Cryopreservation using liquid nitrogen is a method for preserving endangered plants with seeds that can't be stored in a traditional manner, employing a droplet-vitrification protocol that involves multiple steps including osmoprotection and specific regrowth conditions.
  • - The study focused on analyzing organic acids produced during the cryopreservation process to understand their relationship with plant metabolism and stress, using gas chromatography to analyze 14 different acids.
  • - Results showed that the success of shoot tip regeneration was greatest under optimal conditions, with decreasing percentages of successful regrowth linked to deviations in the protocol, emphasizing the importance of maintaining proper conditions for cryopreservation.
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Considering the greater pharmaceutical and clinical interest of triiodothyronine (T ) thyroid hormone, an effective D/L-T enantiomer separation was performed on a crown ether-based chiral stationary phase by LC-MS/MS. In optimal analytical condition and selected reaction monitoring mode, the two enantiomers of T were baseline separated within 10 min. The limit of detection and limit of quantitation were found to be 0.

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Modulation of osteoclast formation could be a therapeutic target for inhibiting pathological bone destruction. The receptor activator of nuclear factor (NF)-κB ligand (RANKL) is known to be an essential factor in osteoclast differentiation and activation inducers. However, whether Protaetia brevitarsis seulensis (P.

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Gamma-hydroxybutyric acid (GHB), both a metabolic precursor and product of gamma-aminobutyric acid (GABA), is a central nervous system depressant used for the treatment of narcolepsy-associated cataplexy and alcohol withdrawal. However, administration of GHB with alcohol (ethanol) is a major cause of hospitalizations related to GHB intoxication. In this study, we investigated locomotor behavior as well as metabolic and pharmacokinetic interactions following co-administration of GHB and ethanol in rats.

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In the present study, to determine the efficacy of oral supplementation of ginseng berry extracts in augmenting exercise performance and exercise-associated metabolism, male mice were given orally 200 and 400 mg/kg of body weight (BW) of GBC for nine weeks. Although there are no differences in pre-exercise blood lactate levels among (1) the control group that received neither exercise nor GBC, (2) the group that performed only twice-weekly endurance exercise, and (3) and (4) the groups that combined twice-weekly endurance exercise with either 200 or 400 mg/kg GBC, statistically significant reductions in post-exercise blood lactate levels were observed in the groups that combined twice-weekly endurance exercise with oral administration of either 200 or 400 mg/kg GBC. Histological analysis showed no muscle hypertrophy, but transcriptome analysis revealed changes in gene sets related to lactate metabolism and mitochondrial function.

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Whereas cholesterol is vital for cell growth, proliferation, and remodeling, dysregulation of cholesterol metabolism is associated with multiple age-related pathologies. Here we show that senescent cells accumulate cholesterol in lysosomes to maintain the senescence-associated secretory phenotype (SASP). We find that induction of cellular senescence by diverse triggers enhances cellular cholesterol metabolism.

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Controlling the crystallinity and surface morphology of perovskite layers by methods such as solvent engineering and methylammonium chloride addition is an effective strategy for achieving high-efficiency perovskite solar cells. In particular, it is essential to deposit α-formamidinium lead iodide (FAPbI) perovskite thin films with few defects due to their excellent crystallinity and large grain size. Here we report the controlled crystallization of perovskite thin films with the combination of alkylammonium chlorides (RACl) added to FAPbI.

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This study investigated the influence of high concentrations of dietary minerals on reducing heat stress (HS)-associated oxidative stress and metabolic alterations in the blood of Holstein and Jersey steers. Holstein steers and Jersey steers were separately maintained under a 3 × 3 Latin square design during the summer conditions. For each trial, the treatments included Control (Con; fed basal TMR without additional mineral supplementation), NM (NRC recommended mineral supplementation group; [basal TMR + (Se 0.

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The statistical distance of conditional distributions is an essential element of generating target data given some data as in video prediction. We establish how the statistical distances between two joint distributions are related to those between two conditional distributions for three popular statistical distances: f-divergence, Wasserstein distance, and integral probability metrics. Such characterization plays a crucial role in deriving a tractable form of the objective function to learn a conditional generator.

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This study describes the enantioseparation of three chiral amines as naphthaldimine derivatives, using normal phase HPLC with amylose and cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phases (CSPs). Three chiral amines were derivatized using three structurally similar naphthaldehyde derivatizing agents, and the enantioselectivity of the CSPs toward the derivatives was examined. The degree of enantioseparation and resolution was affected by the amylose or cellulose-derived CSPs and aromatic moieties as well as a kind of chiral amine.

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Particulate matter (PM) in polluted air can be exposed to the human body through inhalation, ingestion, and skin contact, accumulating in various organs throughout the body. Organ accumulation of PM is a growing health concern, particularly in the cardiovascular system. PM emissions are formed in the air by solid particles, liquid droplets, and fuel - particularly diesel - combustion.

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Nanoparticles have garnered significant interest in neurological research in recent years owing to their efficient penetration of the blood-brain barrier (BBB). However, significant concerns are associated with their harmful effects, including those related to the immune response mediated by microglia, the resident immune cells in the brain, which are exposed to nanoparticles. We analysed the cytotoxic effects of silica-coated magnetic nanoparticles containing rhodamine B isothiocyanate dye [MNPs@SiO(RITC)] in a BV2 microglial cell line using systems toxicological analysis.

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We performed targeted metabolomics with machine learning (ML)-based interpretation to identify metabolites that distinguish the progression of nonalcoholic fatty liver disease (NAFLD) in a cohort. Plasma metabolomics analysis was conducted in healthy control subjects ( = 25) and patients with NAFL ( = 42) and nonalcoholic steatohepatitis (NASH, = 19) by gas chromatography-tandem mass spectrometry (MS/MS) and liquid chromatography-MS/MS as well as RNA sequencing (RNA-seq) analyses on liver tissues from patients with varying stages of NAFLD ( = 12). The resulting metabolomic data were subjected to routine statistical and ML-based analyses and multi-omics interpretation with RNA-seq data.

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Background & Aims: Mitochondrial dysfunction disrupts the synthesis and secretion of digestive enzymes in pancreatic acinar cells and plays a primary role in the etiology of exocrine pancreas disorders. However, the transcriptional mechanisms that regulate mitochondrial function to support acinar cell physiology are poorly understood. Here, we aim to elucidate the function of estrogen-related receptor γ (ERRγ) in pancreatic acinar cell mitochondrial homeostasis and energy production.

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(1) Background: Progression of chronic obstructive pulmonary disease (COPD) leads to irreversible lung damage and inflammatory responses; however, biomarker discovery for monitoring of COPD progression remains challenging. (2) Methods: This study evaluated the metabolic mechanisms and potential biomarkers of COPD through the integrated analysis and receiver operating characteristic (ROC) analysis of metabolic changes in lung, plasma, and urine, and changes in morphological characteristics and pulmonary function in a model of PPE/LPS-induced COPD exacerbation. (3) Results: Metabolic changes in the lungs were evaluated as metabolic reprogramming to counteract the changes caused by the onset of COPD.

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