Publications by authors named "Hey-Jung Park"

Article Synopsis
  • Rapid diagnosis of acute myeloid leukemia (AML) is difficult, especially in patients with myelodysplastic syndrome (MDS) and NPM1 mutations.
  • The study uses holotomography (HT), a 3D imaging technique, alongside machine learning to analyze myeloblast images and detect NPM1 mutations effectively.
  • Results show significant morphological differences between mutated and wild-type NPM1 samples, with high accuracy in detecting these mutations, suggesting HT and deep learning could improve early diagnosis of AML while minimizing the need for complex genetic tests.
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The bioartificial liver (BAL) system can potentially rescue acute liver failure (ALF) patients by providing partial liver function until a suitable donor liver can be found or the native liver has self-regenerated. In this study, we established a suitable cryopreservation process for the development of an off-the-shelf BAL system. The viability of hepatocyte spheroids cryopreserved in liquid nitrogen was comparable to that of fresh primary hepatocyte spheroids.

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Article Synopsis
  • * The new serum-free cryopreservation solutions showed improved cell viability and liver function markers (like ammonia removal and albumin synthesis) in hepatocyte spheroids compared to those using serum.
  • * The cryopreserved spheroid-based bioartificial liver system demonstrated comparable performance to fresh systems in ammonia removal and urea production, making it a promising option for patient treatment.
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Background And Objectives: Mesenchymal stem cells (MSCs) elicit therapeutic effects against liver fibrosis in animal models. Human liver stem cells (HLSCs) are cells isolated from human liver tissue that have mesenchymal morphology and express MSC markers. HLSCs also possess intrahepatic stem cell properties.

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Bioartificial livers (BAL) may offer acute liver failure (ALF) patients an opportunity for cure without liver transplantation. We evaluated the efficacy of a spheroid-based BAL system, containing aggregates of porcine hepatocytes, in a porcine model of ALF. ALF pigs were divided into three groups.

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Purpose: The clinical efficacy of allergen-immunotherapy is known to be dose dependent. However, optimal maintenance dosage has not yet been determined for sublingual immunotherapy (SLIT). Furthermore, since companies adopt their own units for expression of allergenicity, the allergen concentrations of individual reagents cannot be compared easily.

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The first gene encoding gamma-glutamyl transpeptidase (GGTI) of the fission yeast has previously been characterized, and its expression was found to be regulated by various oxidative stress-inducing agents. In this work, a second gene, encoding GGTII, was cloned and characterized from the fission yeast Schizosaccharomyces pombe. The structural gene encoding GGTII was amplified from the genomic DNA of the fission yeast and ligated into the shuttle vector pRS316 to generate the recombinant plasmid pPHJ02.

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In our previous study, the first structural gene (GGTI) encoding g-glutamyl transpeptidase was cloned and characterized from the fission yeast Schizosaccharomyces pombe, and its transcription, using the GGTI-lacZ fusion gene, containing the 1,085 bp upstream region from the translational initiation point, was found to be enhanced by sodium nitroprusside and L-buthionine-(S,R)-sulfoximine (BSO). In the present work, regulation of the GGTI gene was further elucidated. Non-fermentable carbon sources, such as acetate and ethanol, markedly enhanced the synthesis of beta-galactosidase from the GGTI-lacZ fusion gene.

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We have fabricated an field effect transistor (FET)-type DNA charge sensor based on 0.5 microm standard complementary metal oxide semiconductor (CMOS) technology which can detect the deoxyribonucleic acid (DNA) probe's immobilization and information on hybridization by sensing the variation of drain current due to DNA charge and investigated its electrical characteristics. FET-type charge sensor for detecting DNA sequence is a semiconductor sensor measuring the change of electric charge caused by DNA probe's immobilization on the gate metal, based on the field effect mechanism of MOSFET.

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The structural gene for the putative gamma-glutamyl transpeptidase (GGT) was isolated from the chromosomal DNA of the fission yeast Schizosaccharomyces pombe. The determined sequence contained 3324 bp and encoded the predicted 630 amino acid sequence of GGT, which resembles counterparts in Homo sapiens, Rattus norvegicus, Saccharomyces cerevisiae, and Escherichia coli. The S.

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Cellular defense system, including glutathione, glutathione-related enzymes, and antioxidant and redox enzymes, may play crucial roles in the aging of aerobic organisms. To understand the physiological roles of these factors in the aging process, their levels were compared in the livers and brains of 5-week- and 9-month-old rats. GST activity was higher in livers and brains of 9-month-old rats than in those of 5-week-old rats, and brain catalase activity was about 2-fold higher.

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