Publications by authors named "Midori Oyama"

Numerous natural extracts and compounds have been evaluated for their ability to mitigate the adverse effects of ultraviolet (UV) overexposure. However, variability in the UV doses that trigger biological responses across studies likely arises from inconsistencies in UV exposure standardization. We hypothesize that these discrepancies are due to variations in culture plates and dishes.

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Galectins are β-galactoside-binding animal lectins involved in various biological functions, such as host defense. Galectin-2 and -3 are members of the galectin family that are expressed in the stomach, including the gastric mucosa and surface mucous cells. Galectin-3 exhibits aggregation and bactericidal activity against in a β-galactoside-dependent manner.

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Chitosan, a natural cationic polysaccharide derived from crustaceans and shellfish shells, is known for its advantageous biological properties, including biodegradability, biocompatibility, and antibacterial activity. Chitosan and its composite materials are studied for their potential for bone tissue repair. However, the effects of chitosan degradation products, glucosamine (GlcN) and chitosan oligosaccharide (COS), on osteoclasts remain unclear.

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Galectin-1 (Gal-1) is an evolutionarily conserved sugar-binding protein found in intra- and extracellular spaces. Extracellularly, it binds to glycoconjugates with β-galactoside(s) and functions in various biological phenomena, including immunity, cancer, and differentiation. Under extracellular oxidative conditions, Gal-1 undergoes oxidative inactivation, losing its sugar-binding ability, although it exhibits sugar-independent functions.

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Objective: Galectins are sugar-binding proteins that participate in many biological processes, such as immunity, by regulating host immune cells and their direct interaction with pathogens. They are involved in mediating infection by Schistosoma mansoni, a parasitic trematode that causes schistosomiasis. However, their direct effects on schistosomes have not been investigated.

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Xeroderma pigmentosum (XP) is a rare autosomal recessive hereditary disorder. As patients with XP are deficient in nucleotide excision repair, they show severe photosensitivity symptoms. Although skin protection from ultraviolet (UV) radiation is essential to improve the life expectancy of such patients, the optimal protective effect is not achieved even with sunscreen application, owing to the low usability of the preparations.

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Osteopontin (OPN) plays a pivotal role in cancer cell invasion and metastasis. Although OPN has a large number of phosphorylation sites, the functional significance of OPN phosphorylation in cancer cell motility remains unclear. In this study, we attempted to investigate whether phosphorylated OPN secreted from cancer cells affect cancer cell migration.

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Epithelial-mesenchymal transition (EMT) plays a pivotal role for tumor progression. Recent studies have revealed the existence of distinct intermediate states in EMT (partial EMT); however, the mechanisms underlying partial EMT are not fully understood. Here, we demonstrate that αvβ3 integrin induces partial EMT, which is characterized by acquiring mesenchymal phenotypes while retaining epithelial markers.

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Osteoclasts are the only bone-resorbing cells in organisms and understanding their differentiation mechanism is crucial for the treatment of osteoporosis. In the present study, we investigated the effect of Thiamet G, an O-GlcNAcase specific inhibitor, on osteoclastogenic differentiation. Thiamet G treatment increased global O-GlcNAcylation in murine RAW264 cells and suppressed receptor activator of nuclear factor-κB ligand (RANKL)-dependent formation in tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells, thereby suppressing the upregulation of osteoclast specific genes.

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α6β4 integrin plays pivotal roles in cancer progression in several types of cancers. Our previous study using N-glycan-manipulated cell lines demonstrated that defects in N-glycans or decreased β1,6GlcNAc-branched N-glycans on β4 integrin suppress β4 integrin-mediated cancer cell adhesion, migration, invasion, and tumorigenesis. Furthermore, immunohistochemical analysis has shown that colocalization of β1,6GlcNAc-branched N-glycans with β4 integrin was observed in cutaneous squamous cell carcinoma (SCC) tissue.

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is associated with the onset of gastritis, peptic ulcers, and gastric cancer. Galectins are a family of β-galactoside-binding proteins involved in diverse biological phenomena. Galectin-2 (Gal-2), a member of the galectin family, is predominantly expressed in the gastrointestinal tract.

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TAFRO syndrome is rare, and its pathophysiology remains unclear. We herein report the case of a 66-year-old man who presented at our emergency department with epigastric pain. Contrast-enhanced computed tomography (CT) showed high-density retroperitoneal panniculus with contrast enhancement.

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Background: To evaluate renal function, the indices of estimated glomerular filtration rate (eGFR) obtained using several equations, including the Japanese versions of the serum creatinine-based MDRD equation (eGFRcreat), Chronic Kidney Disease Epidemiology Collaboration equation (eGFR-EPI), and serum cystatin C-based equation (eGFRcys), are utilized. This study prospectively examined the association between these eGFR values and all-cause mortality during a 12-year observational period in a community-based population.

Methods And Results: The subjects of this study were 1312 participants undergoing a health checkup, aged ≥40 years.

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Osteopontin (OPN) is an extracellular glycosylated phosphoprotein that promotes cell adhesion by interacting with several integrin receptors. We previously reported that an OPN mutant lacking five O-glycosylation sites (Thr/Thr/Thr/Thr/Thr) in the threonine/proline-rich region increased cell adhesion activity and phosphorylation compared with the wild type. However, the role of O-glycosylation in cell adhesion activity and phosphorylation of OPN remains to be clarified.

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Malignant transformation is associated with aberrant -glycosylation, but the role of protein -glycosylation in cancer progression remains poorly defined. β4-integrin is a major carrier of -glycans and is associated with poor prognosis, tumorigenesis, and metastasis. Here, -glycosylation of β4-integrin contributes to the activation of signaling pathways that promote β4-dependent tumor development and progression.

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