Masanori Okamoto

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Wnt regulates bone formation through β-catenin-dependent canonical and -independent noncanonical signaling pathways. However, the cooperation that exists between the two signaling pathways during osteoblastogenesis remains to be elucidated. Here, we showed that the lack of Wnt5a in osteoblast-lineage cells impaired Wnt/β-catenin signaling due to the reduced(More)
Recent advances in technologies for observing high-resolution genomic activities, such as whole-genome tiling arrays and high-throughput sequencers, provide detailed information for understanding genome functions. However, the functions of 50% of known Arabidopsis thaliana genes remain unknown or are annotated only on the basis of static analyses such as(More)
This study aimed to investigate the influence of the shape and size of multi-walled carbon nanotubes (MWCNTs) and cup-stacked carbon nanotubes (CSCNTs) on biological responses in vitro. Three types of MWCNTs - VGCF(®)-X, VGCF(®)-S, and VGCF(®) (vapor grown carbon fibers; with diameters of 15, 80, and 150 nm, respectively) - and three CSCNTs of different(More)
Although there have been many reports about the cytotoxicity of multi-walled carbon nanotubes (MWCNTs), the results are still controversial. To investigate one possible reason, the authors investigated the influence of MWCNT dispersants on cellular uptake and cytotoxicity. Cytotoxicity was examined (measured by alamarBlue(®) assay), as well as intracellular(More)
We examined differences in cellular responses to multi-walled carbon nanotubes (MWCNTs) using malignant pleural mesothelioma cells (MESO-1), bronchial epithelial cells (BEAS-2B), neuroblastoma cells (IMR-32), and monoblastic cells (THP-1), before and after differentiation. MESO-1, BEAS-2B and differentiated THP-1 cells actively endocytosed MWCNTs, resulting(More)
The application of carbon nanotubes (CNTs) as biomaterials is of wide interest, and studies examining their application in medicine have had considerable significance. Biological safety is the most important factor when considering the clinical application of CNTs as biomaterials, and various toxicity evaluations are required. Among these evaluations,(More)
BACKGROUND In the present study, we investigated whether DJ-1 could serve as a biomarker for assessing the biocompatibility of multiwalled carbon nanotubes (MWCNTs), using the highly purified carbon nanotube, HTT2800. METHODS Using Western blot analysis, we determined DJ-1 protein levels in two different types of cells (one capable and the other incapable(More)
Bronchial epithelial cells and mesothelial cells are crucial targets for the safety assessment of inhalation of carbon nanotubes (CNTs), which resemble asbestos particles in shape. Intrinsic properties of multiwalled CNTs (MWCNTs) are known to cause potentially hazardous effects on intracellular and extracellular pathways. These interactions alter cellular(More)
Kidney transplant recipients develop secondary osteoporosis induced by immunosuppressive medication, with a high risk of fracture, and abdominal aortic calcification (AC) is a known predictor of cardiovascular mortality. In this study of 12 stable kidney recipients, we estimated the preventive effect of bisphosphonate treatment on bone loss and progression(More)