Publications by authors named "Seijin Park"

Current research suggests therapy-induced senescence (TIS) of cancer cells characterized by distinct morphological and biochemical phenotypic changes represent a novel functional target that may enhance the effectiveness of cancer therapy. In order to identify novel small-molecule inducers of cellular senescence and determine the potential to be used for the treatment of melanoma, a new method of high-throughput screening (HTS) and high-contents screening (HCS) based on the detection of morphological changes was designed. This image-based and whole cell-based technology was applied to screen and select a novel class of antiproliferative agents on cancer cells, 4H-chromeno[2,3-d]pyrimidin-4-one derivatives, which induced senescence-like phenotypic changes in human melanoma A375 cells without serious cytotoxicity against normal cells.

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Pathogens have evolved a range of mechanisms to counteract host defenses, notably to survive harsh acidic conditions in phagosomes. In the case of Mycobacterium tuberculosis, it has been shown that regulation of phagosome acidification could be achieved by interfering with the retention of the V-ATPase complexes at the vacuole. Here, we present evidence that M.

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A critical unmet clinical need to combat the global tuberculosis epidemic is the development of potent agents capable of reducing the time of multi-drug-resistant (MDR) and extensively-drug-resistant (XDR) tuberculosis therapy. In this paper, we report on the optimization of imidazo[1,2-a]pyridine amide (IPA) lead compound 1, which led to the design and synthesis of Q203 (50). We found that the amide linker with IPA core is very important for activity against Mycobacterium tuberculosis H37Rv.

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New therapeutic strategies are needed to combat the tuberculosis pandemic and the spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) forms of the disease, which remain a serious public health challenge worldwide. The most urgent clinical need is to discover potent agents capable of reducing the duration of MDR and XDR tuberculosis therapy with a success rate comparable to that of current therapies for drug-susceptible tuberculosis. The last decade has seen the discovery of new agent classes for the management of tuberculosis, several of which are currently in clinical trials.

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Identification of secondary metabolites produced by cryptic gene in bacteria may be difficult, but in the case of nonribosomal peptide (NRP)-type secondary metabolites, this study can be facilitated by bioinformatic analysis of the biosynthetic gene cluster and tandem mass spectrometry analysis. To illustrate this concept, we used mass spectrometry-guided bioinformatic analysis of genomic sequences to identify an NRP-type secondary metabolite from Streptomyces peucetius ATCC 27952. Five putative NRPS biosynthetic gene clusters were identified in the S.

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Article Synopsis
  • * Researchers created a high-throughput assay to analyze over 11,000 mutant strains of M. tuberculosis, using fluorescent staining and automated confocal microscopy to track their behavior within cells.
  • * They identified ten key mutants that struggle with phagosomal maturation, uncovering disruptions in genes related to cell structure and lipid biosynthesis, specifically involving acyltrehalose-containing glycolipids, which are vital for the bacterium's survival in early infection stages.
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Objective: To determine whether triamcinolone acetonide diffuses from the distal interphalangeal joint (DIPJ) to the navicular bursa, diffusion is direct or systemic, and addition of sodium hyaluronan has an effect on diffusion in horses.

Animals: 11 adult horses without forelimb lameness.

Procedures: 1 randomly chosen forelimb DIPJ of each horse received an injection of 10 mg of triamcinolone acetonide plus 20 mg of sodium hyaluronan (group 1), and the contralateral forelimb DIPJ received an injection of 10 mg of triamcinolone acetonide plus 2 mL of lactated Ringer's solution (group 2).

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Introduction: The purpose of this study was to evaluate the efficacy of conservative treatment with progestin and pregnancy outcomes in women with early-stage endometrial cancer.

Methods: We retrospectively analyzed the medical records of 35 patients with endometrial adenocarcinoma, who were treated with progestin from January 1996 to December 2006. Women with early-stage grade 1 endometrioid endometrial adenocarcinoma, who wanted to receive conservative treatment or preserve fertility, were included.

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The seed protein IAP1 from bean (PvIAP1; Phaseolus vulgaris L.) that is modified by the phytohormone indole-3-acetic acid (IAA) was heterologously expressed in the two reference plant species Arabidopsis thaliana and Medicago truncatula. For the transformation of Medicago we devised a novel protocol using seedling infiltration.

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Achenes and receptacle tissue of Fragaria vesca, L. cultivar Yellow Wonder were shown to contain conjugated indole-3-acetic acid (IAA) that was not soluble in organic solvents and yielded IAA after strong alkaline hydrolysis, suggestive of IAA attached to plant proteins. This solvent insoluble conjugated IAA accounted for between 0.

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Indole-3-acetic acid is an indispensable hormone (auxin) in plants and an important metabolite in humans, animals, and microorganisms. Here we introduce its 5- and 6-(2-aminoethyl)-derivatives for use in the design of novel research tools, such as immobilized and carrier-linked forms of indole-3-acetic acid and its conjugates with biochemical tags or biocompatible molecular probes. The aliphatic nitrogens of 5- and 6-(2-aminoethyl)indole were acetylated and the products were converted to the corresponding 3-(N,N-dimethylamino)methyl derivatives (gramines).

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Gibberellins (GAs) in developing seeds of morning glory (Pharbitis nil) were quantified and localized by immunostaining. The starch grains began to be digested after the GA contents had increased and reached a plateau. Immunohistochemical staining with the antigibberellin A(1)-methyl ester-antiserum, which has high affinity to biologically active GAs, showed that GA(1) and/or GA(3) were localized around starch grains in the integument of developing young seeds, suggesting the participation of GA-inducible alpha-amylase in this digestion.

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We show that the expression of an indole-3-acetic acid (IAA)-modified protein from bean seed, IAP1, is correlated to the developmental period of rapid growth during seed development. Moreover, this protein undergoes rapid degradation during germination. The gene for IAP1, the most abundant protein covalently modified by IAA (iap1, GenBank accession no.

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