Publications by authors named "Yuka Kiba"

Two novel aromatic polyketides, penicanesins J and K (1, 2), were isolated from the marine-derived fungus Didymella aeria, along with the known compound integrastatin B (3). The structures of the new compounds were determined by NMR spectroscopy and synthetic methods. The isolated compounds were tested for monoamine oxidase (MAO) B inhibition, anti-amyloid beta (Aβ) aggregation, and protective activity against HO-induced cell death in human neuroblastoma SH-SY5Y cells.

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This study proposes a sequential liquid dispensing method using a centrifugal microfluidic device operating at a constant rotational speed for the multiplexed genetic detection of nucleic acid targets across multiple samples in a single operation. A pair of passive valves integrated into each microchamber enabled the liquid to fill towards the center of rotation against the centrifugal force, facilitating the complete removal of air inside the microchamber. Liquid manipulation can be achievable without any surface coating of the device by exploiting the inherent hydrophobicity of the polymer.

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The emergence of coronavirus disease 2019 (COVID-19), a novel identified pneumonia resulting from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, has significantly impacted and posed significant challenges to human society. The papain-like protease (PLpro) found in the nonstructural protein 3 of SARS-CoV-2 plays a vital role in viral replication. Moreover, PLpro disrupts the host immune response by cleaving ubiquitin and interferon-stimulated gene 15 from host proteins.

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Papain-like protease (PLpro) enzyme plays a vital role in viral replication as it breaks down polyproteins and disrupts the host's immune response. There are few reports on Kampo formulas that focus on PLpro activity. In this study, we evaluated the inhibitory effects of senkyuchachosan, a traditional Japanese medicine, on PLpro of SARS-CoV-2, the virus responsible for causing COVID-19.

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A novel tricyclic polyketide, curvulanone (1), was isolated from the marine-derived fungus Curvularia aeria. The structure of 1 was determined by NMR and single-crystal X-ray crystallography. 1 had a cyclopentabenzopyranone with 3-acetic acid structure that is rarely found in natural compounds.

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Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), spread as a pandemic and caused damage to people's lives and countries' economies. The spike (S) protein of SARS-CoV-2 contains a cleavage motif, Arg-X-X-Arg, for furin and furin-like enzymes at the boundary of the S1/S2 subunits. Given that cleavage plays a crucial role in S protein activation and viral entry, the cleavage motif was selected as the target.

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The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged as a pandemic and has inflicted enormous damage on the lives of the people and economy of many countries worldwide. However, therapeutic agents against SARS-CoV-2 remain unclear. SARS-CoV-2 has a spike protein (S protein), and cleavage of the S protein is essential for viral entry.

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Cell adhesion plays a crucial role in candidiasis through invasion of the human body and obtaining resistance to drugs by forming biofilms. Cell adhesion thus is a critical target for combating candidiasis by preventing the entry of fungal hyphae into the epithelium. We report here that dehydrocurvularin (1), isolated from the marine-derived fungus Curvularia aeria, exhibited anti-fungal activities for Candida albicans and Candida auris.

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Poria, the dried sclerotium of Wolfiporia cocos, is a medicinal mushroom that is widely used in traditional Japanese medicine. The fruit body of W. cocos is rarely found in the natural environment in Japan, therefore an optimized technique for fruit body formation is essential for producing new strains through crossbreeding and for biological research.

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The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contains a cleavage motif R-X-X-R for furin-like enzymes at the boundary of the S1/S2 subunits. The cleavage of the site by cellular proteases is essential for S protein activation and virus entry. We screened the inhibitory effects of crude drugs on in vitro furin-like enzymatic activities using a fluorogenic substrate with whole-cell lysates.

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Hemp ( L.) seed contains high contents of various nutrients, including fatty acids and proteins. Cannabidiol (CBD) is a non-psychoactive compound that can be extracted from and used for treating epilepsy and pain.

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