Publications by authors named "Ki Bbeum Kim"

Hydrogen peroxide (H2O2) is a reactive oxygen species (ROS) that induces numerous cellular events, including cellular senescence and inflammatory responses. Therefore, the aim of this study was to investigate the protective effect of Rosmarinic acid (RA) in H2O2‑induced oxidative stress in normal human dermal fibroblasts (NHDFs). Cytotoxicity assays were performed using a water‑soluble tetrazolium salt, and senescence‑associated β‑galactosidase activity was determined to investigate the proportion of senescent cells.

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Ultraviolet (UV) light exposure causes skin photoaging, which is known to be preventable and controllable by application of UV-protective agents. In this study, we demonstrated, for the first time, that the extract of microalgae Arthrospira platensis has a reverse effect on UV-induced photodamage such as loss of cell viability, cellular senescence, DNA damage, and collagen destruction in dermal fibroblasts. Forty-eight extracts were prepared from the cell biomass by controlling culture light conditions, extract solvents, and disruption methods.

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A number of phosphodiesterase 5 (PDE5) inhibitors approved by authorities have been used successfully in the treatment of erectile dysfunction. These medicines must be prescribed carefully due to their adverse effects, but they and their analogues are being illegally added to dietary supplements. These illegal dietary supplements pose a significant risk to public health.

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Background: Ultraviolet A (UVA), one of the major components of sunlight, can penetrate the dermal layer of the skin and generate reactive oxygen species (ROS). It causes alterations in the dermal connective tissue and gene expression, inflammation, photoaging, and DNA damage.

Aims: Therefore, the harmful effects of UVA and strategies to reduce it have been consistently investigated.

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Background: Approximately 90%~99% of ultraviolet A (UVA) ray reaches the Earth's surface. The deeply penetrating UVA rays induce the formation of reactive oxygen species (ROS), which results in oxidative stress such as photoproducts, senescence, and cell death. Thus, UVA is considered a primary factor that promotes skin aging.

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This erratum is being published to correct the errors of the words in the section of Result and the Figure 4B. The words of 'with HO' (left column, line 25) in page 781 should be corrected as 'with the extract'. And the Figure 4B in page 780 should be replaced with the below new Figure 4B.

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The identification of novel reagents that exert a biological ultraviolet (UV)-protective effect in skin cells represents an important strategy for preventing UV-induced skin aging. To this end, we investigated the potential protective effects of Ettlia sp. YC001 extracts against UV-induced cellular damage in normal human dermal fibroblasts (NHDFs).

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N-Imidoylation of sulfoximines is developed from a Cu-catalyzed three-component reaction from 1-alkynes, N-sulfonyl azides, and sulfoximines in THF at room temperature under air. In addition, N-oxoimidoylation of sulfoximines is accessed from a Cu-catalyzed three-component reaction from 1-alkynes, N-sulfonyl azides, and sulfoximines in THF at room temperature followed by a Cu-catalyzed oxidative reaction at 50 °C under air, producing N-oxoimidoyl sulfoximines.

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Asiatic acid, a triterpenoid derived from Centella asiatica, is a putative anticancer agent in several types of cancer cells. Investigations of its biological role in negative regulation of cell growth have focused on the extent of induction of apoptosis in a cell-type-specific manner. In this study, we identified an important regulator of asiatic acid-induced cell death, microRNA (miR)-1290, which sensitizes cells to asiatic acid-induced cytotoxicity and negatively regulates BCL2 expression.

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