Publications by authors named "Jiyoung Park"

In this study, twelve neuraminidase (NA) inhibitory compounds 1-12 were isolated from heartwood of Caesalpinia sappan on the basis of their biological activities against three types of viral NAs. Of isolated homoisoflavonoids, sappanone A (2) showed the most potent NAs inhibitory activities with IC(50) values of 0.7 µM [H1N1], 1.

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Parkinson disease (PD) is the second most common neurodegenerative disease characterized by a progressive dopaminergic neuronal loss in association with Lewy body inclusions. Gathering evidence indicates that α-synuclein (α-syn), a major component of the Lewy body, plays an important role in the pathogenesis of PD. Although α-syn is considered to be a cytoplasmic protein, it has been detected in extracellular biological fluids, including human cerebrospinal fluid and blood plasma of healthy and diseased individuals.

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We investigated the degree of lot-to-lot reagent variation for 5 common immunoassay items. We measured the commercial as well as in-house controls for α-fetoprotein (AFP), ferritin, CA19-9, quantitative hepatitis B surface antigen (HBsAg), and hepatitis B surface antibody (anti-HBs) 10 times each by using both the old and the new lot of reagents whenever a reagent lot was changed, over a period of 10 months. The differences in the mean control values, the percent difference (% difference), and the difference to between-run standard deviation ratio (D:SD ratio) between successive lots were calculated.

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Background: We performed surveillance cultures of the surfaces of X-ray cassettes to assess contamination with methicillin-resistant Staphylococcus aureus (MRSA).

Methods: The surfaces of 37 X-ray cassettes stored in a radiology department were cultured using mannitol salt agar containing 6 µg/mL oxacillin. Suspected methicillin-resistant staphylococcal colonies were isolated and identified by biochemical testing.

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Although it is commonly assumed that social support positively predicts health, the empirical evidence has been inconsistent. We argue that three moderating factors must be considered: (1) support-approving norms (cultural context); (2) support-requiring situations (stressful events); and (3) support-accepting personal style (low neuroticism). Our large-scale cross-cultural survey of Japanese and US adults found significant associations between perceived support and health.

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We propose a new dispersion control scheme by introducing hollow ring defects having a central air hole and a GeO2-or F-doped silica ring with in a square lattice photonic crystal fiber. We confirmed the flexible dispersion controllability in the proposed structure in two aspects of dispersion managements: ultra-flattened near-zero dispersion in the 530 nm-bandwidth over all communication bands and dispersion compensation in C, L, and U band with a high compensation ratio of 0.96~1.

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Wild-type p53-induced phosphatase 1 (Wip1, PPM1D) is induced by p53 in response to various stressors and dephosphorylates cellular target proteins involved in DNA repair and cell cycle checkpoint pathways. The Wip1 gene is frequently amplified or overexpressed in human cancers, promoting tumor growth by switching off major checkpoint kinases and p53. To explore wild-type p53-independent Wip1 induction, Wip1 promoter activity and its transcript level were evaluated by luciferase assay and real-time PCR, after methylmethane sulfonate (MMS) treatment in breast cancer cell lines and p53-null cell lines.

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ABC transporters constitute one of the largest protein families found in all living organisms. ABC transporters are driven by ATP hydrolysis and can act as exporters as well as importers. The plant genome encodes for more than 100 ABC transporters, largely exceeding that of other organisms.

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Sialidases are enzymes that catalyze the hydrolysis of sialic acid residues from various glycoconjugates, which are widely found in a number of viral and microbial pathogens. In this study, we investigated the biological evaluation of isolated six shikonins (1-6) and three shikonofurans (7-9) from Lithospermum erythrorhizon. The nine isolated compounds 1-9 showed strong and selective inhibition of glycosyl hydrolase (GH) 33 and -34 sialidases activities.

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Objectives: Ethylene glycol monomethyl ether (EGME) and ethylene glycol monomethyl ether acetate (EGMEA) are widely used in industries as solvents for coatings, paint and ink, but exposure data are limited because they are minor components out of mixed solvents, as well as because of inconsistency in desorption solvent use. The objective of this study was to investigate the worker exposure profile of EGME and EGMEA.

Methods: Our study investigated 27 workplaces from June to September 2008 and detected EGME and EGMEA in 20 and 13, respectively.

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CD1d is an MHC class I-like molecule that presents glycolipid Ags to types I and II NKT cells. The YxxI motif in the cytoplasmic tail of CD1d contributes to its intracellular localization to the endolysosomal compartment and is important for Ag presentation to type I NKT cells. In this study, we identified the (327-329)RRR motif in CD1d and showed that it is critical for the control of CD1d intracellular trafficking and Ag presentation.

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A series of sesquiterpenes and hinokitiol-related compounds (1-15) was isolated from the essential oil of Thujopsis dolabrata Sieb. et Zucc. var.

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Aquaporin (AQP) is a family of transmembrane proteins for water transport. Recent studies revealed that AQPs are likely to play a role in tumor progression and invasion. We aimed to examine the potential role of AQP5 in the progression of human breast cancer cells.

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Background: Whether low molecular weight heparin (LMWH) enoxaparin is equivalent to unfractionated heparin (UFH) in patients with non-ST-segment elevation myocardial infarction (NSTEMI) undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES) remains unclear.

Methods: A total of 2397 NSTEMI patients who underwent PCI with DES received either LMWH [n=1178, subcutaneous enoxaparin 1 mg/kg, b.i.

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Heavy metals such as cadmium (Cd) and mercury (Hg) are toxic pollutants that are detrimental to living organisms. Plants employ a two-step mechanism to detoxify toxic ions. First, phytochelatins bind to the toxic ion, and then the metal-phytochelatin complex is sequestered in the vacuole.

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This paper deals with cerebral paragonimiasis and cerebral hemispherectomy conducted as a treatment of cerebral paragonimiasis by Bo Sung Sim in Korea in 1950s-1960s. He demonstrated that cerebral hemispherectomy could be used for unilateral diffuse cerebral paragonimiasis. Sim learned cerebral hemispherectomy from Dr.

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Huanglongbing (HLB) is a destructive disease of citrus trees caused by phloem-limited bacteria, Candidatus Liberibacter spp. One of the early microscopic manifestations of HLB is excessive starch accumulation in leaf chloroplasts. We hypothesize that the causative bacteria in the phloem may intervene photoassimilate export, causing the starch to over-accumulate.

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As part of our ongoing effort to develop influenza virus neuraminidase (NA) inhibitors from various medicinal plants, we utilized bioassay-guided fractionation to isolated six alkylated chalcones (1-6) from Angelica keiskei. Xanthokeistal A (1) emerged as new compound containing the rare alkyl substitution, 6,6-dimethoxy-3-methylhex-2-enyl. When we tested the ability of these individual alkyl substituted chalcones to inhibit influenza virus NA hydrolysis, we found that 2-hydroxy-3-methyl-3-butenyl alkyl (HMB) substituted chalcone (3, IC(50)=12.

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Background: Donepezil is a potent inhibitor of acetylcholinesterase, an enzyme that is targeted in the treatment of Alzheimer's disease.

Objective: The purpose of this study was to compare the pharmacokinetic characteristics of orally disintegrating (test) and conventional (reference) donepezil formulations to satisfy the regulatory requirement for marketing.

Methods: A single-center randomized, single-dose, open-label, 2-way crossover study with a 21-day washout period was conducted in 22 healthy volunteers.

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Article Synopsis
  • Determining the right warfarin dose and maintaining target PT-INR levels is difficult, with genetic differences potentially impacting individual dosage needs.
  • The study focused on Korean patients starting warfarin therapy, examining how the CYP2C9 and VKORC1 genes affect their response to the medication.
  • Findings revealed that specific genotypes were common among participants, and certain genetic variations led to differences in warfarin dosing and PT-INR responses, suggesting that genetic testing may help tailor anticoagulation therapy.
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There is growing evidence that obesity is a risk factor of cancer incidence and mortality. Hence, the identification of the mechanistic links between obesity and cancer progression is emerging as a topic of widespread interest. Recently, several groups have addressed the functional roles of leptin, an adipocyte-derived adipokine, for mammary tumor progression.

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The past few years have provided substantial evidence for the vital role of the local tumor microenvironment for various aspects of tumor progression. With obesity and its pathophysiological sequelae still on the rise, the adipocyte is increasingly moving center stage in the context of tumor stroma-related studies. To date, we have limited insight into how the systemic metabolic changes associated with obesity and the concomitant modification of the paracrine and endocrine panel of stromal adipocyte-derived secretory products ("adipokines") influence the incidence and progression of obesity-related cancers.

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Influenza A virus infections continue to pose a major threat to humans and several animal species. Neuraminidase (NA) is one of the most promising targets for the development of drugs against influenza viruses because of its critical role in the viral life cycle. During the course of a search for NA inhibitors from edible natural sources, we found that the ethyl acetate layer of ethanol extracts of Ecklonia cava showed extremely high NA-inhibitory activity (72.

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Article Synopsis
  • The study investigates the link between the DRD2 gene and tardive dyskinesia (TD) in patients with schizophrenia taking antipsychotics.
  • None of the five specific DRD2 gene variations assessed were significantly related to the presence or severity of TD.
  • One rare haplotype showed a notable difference between groups, but overall results suggest the DRD2 gene may not play a significant role in TD for this Korean population, indicating a need for further research.
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Spatial working memory (WM) processing has 3 distinct phases: encoding, maintenance, and retrieval and its dysfunction is a core feature in schizophrenia. We examined phase-specific brain activations associated with spatial WM in first-degree relatives of schizophrenia (genetic high risk, GHR), ultra-high risk (UHR) subjects, patients with schizophrenia, and healthy controls. We used an event-related functional magnetic resonance imaging in 17 GHR subjects, 21 UHR subjects, 15 clinically stable patients with schizophrenia and 16 healthy controls, while subjects were performing a spatial delayed-response task.

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