記述言語：英語   掲載種別：研究論文（学術雑誌）  

Zirconia ceramics have been widely used in dentistry. Herein, we assess the surface morphology, surface texture, and osteoblast response of additively manufactured zirconia and alumina-toughened zirconia (ATZ) in comparison with titanium. The surface roughness, contact angle, and surface microstructure of titanium sandblasted with large-grit alumina and subsequently acid-etched using 18% HCl and 49% H2SO4 (SLA-titanium), uniaxially pressed zirconia (UP zirconia), additively manufactured zirconia (AM zirconia), and additively manufactured ATZ (AM ATZ) were investigated. Moreover, the cell viability, alkaline phosphatase (ALP) activity, and gene expression of type I collagen on these materials were evaluated. The data were statistically analyzed using one-way ANOVA with Tukey's post hoc test. SLA-titanium showed the highest surface roughness and contact angle. The other three materials showed comparable surface roughness and contact angles. Micro- and nanoroughness were observed on the surface of SLA-titanium. UP zirconia and AM zirconia had similar surface morphologies. The cell viability, ALP activity, and gene expression of type I collagen on AM zirconia were comparable to or better than those on SLA-titanium. Our results indicate that AM zirconia is a promising material for zirconia dental implants.

DOI： 10.3390/ma15238685

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

This study investigated the effects of a multifunctional acrylate copolymer-Trimethylolpropane Triacrylate (TMPTA) and Di-pentaerythritol Polyacrylate (A-DPH)-on the mechanical properties of chemically polymerized acrylic resin and its bond strength to a CAD/CAM polymethyl methacrylate (PMMA) disk. The methyl methacrylate (MMA) samples were doped with one of the following comonomers: TMPTA, A-DPH, or Trimethylolpropane Trimethacrylate (TMPTMA). The doping ratio ranged from 10 wt% to 50 wt% in 10 wt% increments. The flexural strength (FS) and modulus (FM) of PMMA with and without comonomer doping, as well as the shear bond strength (SBS) between the comonomer-doped PMMA and CAD/CAM PMMA disk, were evaluated. The highest FS (93.2 ± 4.2 MPa) was obtained when doped with 20 wt% of TMPTA. For TMPTMA, the FS decreased with the increase in the doping ratio. For SBS, TMPTA showed almost constant values (ranging from 7.0 to 8.2 MPa) regardless of the doping amount, and A-DPH peaked at 10 wt% doping (8.7 ± 2.2 MPa). TMPTMA showed two peaks at 10 wt% (7.2 ± 2.6 MPa) and 40 wt% (6.5 ± 2.3 MPa). Regarding the failure mode, TMPTMA showed mostly adhesive failure between the CAD/CAM PMMA disk and acrylic resin while TMPTA and A-DPH showed an increased rate of cohesive or mixed failures. Acrylate's addition as a comonomer to PMMA provided improved mechanical properties and bond strength to the CAD/CAM PMMA disk.

DOI： 10.3390/ma15217564

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Bone apatite crystals grow in clusters, but the microstructure of these clusters is unknown. This study compares the structural and compositional differences between bone apatite clusters formed in intramembranous (IO) and endochondral ossification (EO). Calvaria (IO) and femurs (EO) are isolated from mice at embryonic days (E) 14.5 to 15.5 and post-natal days (P) 6 to 7, respectively. Results show that the initially formed bone apatite clusters in EO (≅1.2 µm2 ) are >10 times larger than those in IO (≅0.1 µm2 ), without significant changes in ion composition. In IO (E14.5 calvarium), early minerals are formed inside matrix vesicles (MVs). In contrast, in EO (P6 femur epiphysis), no MVs are observed, and chondrocyte-derived plasma membrane nanofragments (PMNFs) are the nucleation site for mineralization. Apatite cluster size difference is linked with the different nucleation sites. Moreover, an alkaline pH and slow P supply into a Ca-rich microenvironment are suggested to facilitate apatite cluster growth, as demonstrated in a biomimetic mineralization system. Together, the results reveal for the first time the distinct and exquisite microstructures of bone apatite clusters in IO and EO, and provide insightful inspirations for the design of more efficient materials for bone tissue engineering and repair.

DOI： 10.1002/adbi.202200076

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

All-ceramic restorations have become increasingly popular in dentistry. Toward ensuring that these restorations adhere to the tooth structure, this study determines the optimal femtosecond laser (FL) treatment parameters for lithium disilicate glass-ceramics and highly translucent zirconia ceramics with respect to surface morphology. For both the ceramics, the following surface conditions were investigated: (1) as-sintered; (2) Al2O3 sandblasted; (3) FL treatment (dot pattern with line distances of 14, 20, and 40 µm); (4) FL treatment (crossed-line pattern with a line distance of 20 and 40 µm). Surface roughness parameters were estimated using a 3D confocal laser microscope; microstructures were analyzed using a scanning electron microscope. Peak fluence (Fpeak) values of 4 and 8 J/cm2 and irradiation numbers (N) of 20 and 10 shots were selected to create dot patterns in highly translucent zirconia and lithium disilicate glass-ceramics, respectively. Furthermore, Fpeak = 8 J/cm2 and N = 20 shots were chosen to obtain crossed-line patterns in both ceramics. Our results show that lithium disilicate glass-ceramics and highly translucent zirconia exhibit a similar surface morphology under each of the surface treatment conditions. Therefore, FL irradiation of dot or crossed-line patterns (at a distance of 20 and 40 µm) are potential candidates for future investigations.

DOI： 10.3390/ma15103614

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Inorganic pigments have been widely used due to their low cost of production, strong hiding power, and chemical resistance; nevertheless, they have limited hue width and chromaticity. To eliminate these disadvantages, we herein propose the use of an ingenious biotemplate technique to produce Al-enriched biogenic iron oxide (BIOX) materials. Spectrophotometric color analysis showed that high levels of Al inclusion on heat-treated BIOX samples produced heightened yellowish hues and lightness. The Al-enriched BIOX sheaths exhibited a stable tubular structure and excellent thermal stability of color tones after heating at high temperatures and repetitive heat treatments. Ultrastructural analysis and mechanical destruction experiments revealed that the highly chromatic orange-hue of these pigments are ascribed probably to an ingenious cylindrical nanocomposite architecture composed of putative Fe-included low crystalline Al oxide regions and hematite particles embedded therein. The present work therefore demonstrates that the bioengineered material can serve as an epochal orange-hued inorganic pigment with low toxicity and marked thermostability that should meet large industrial demand.

DOI： 10.1021/acsomega.1c07390

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media LLC  

INTRODUCTION: Osteocytes play a role as mechanosensory cells by sensing flow-induced mechanical stimuli applied on their cell processes. High-resolution imaging of osteocyte processes and the canalicular wall are necessary for the analysis of this mechanosensing mechanism. Focused ion beam-scanning electron microscopy (FIB-SEM) enabled the visualization of the structure at the nanometer scale with thousands of serial-section SEM images. We applied machine learning for the automatic semantic segmentation of osteocyte processes and canalicular wall and performed a morphometric analysis using three-dimensionally reconstructed images. MATERIALS AND METHODS: Six-week-old-mice femur were used. Osteocyte processes and canaliculi were observed at a resolution of 2 nm/voxel in a 4 × 4 μm region with 2000 serial-section SEM images. Machine learning was used for automatic semantic segmentation of the osteocyte processes and canaliculi from serial-section SEM images. The results of semantic segmentation were evaluated using the dice similarity coefficient (DSC). The segmented data were reconstructed to create three-dimensional images and a morphological analysis was performed. RESULTS: The DSC was > 83%. Using the segmented data, a three-dimensional image of approximately 3.5 μm in length was reconstructed. The morphometric analysis revealed that the median osteocyte process diameter was 73.8 ± 18.0 nm, and the median pericellular fluid space around the osteocyte process was 40.0 ± 17.5 nm. CONCLUSION: We used machine learning for the semantic segmentation of osteocyte processes and canalicular wall for the first time, and performed a morphological analysis using three-dimensionally reconstructed images.

DOI： 10.1007/s00774-022-01321-x

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その他リンク： https://link.springer.com/article/10.1007/s00774-022-01321-x/fulltext.html

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Nitrogen/phosphorus-containing melamines (NPCM), a durable flame-retardant, were prepared by the successive treatment of ArOH (Ar = Br n C6H5-n , n = 0, 1, 2, and 3) with POCl3 and melamine monomer. The prepared flame-retardants were grafted through the CH2 unit to lignocellulose nanofibers (LCNFs) by the Mannich reaction. The resulting three-component products were characterized using FT-IR (ATR) and EA. The thermal behavior of the NPCM-treated LCNF fabric samples was determined using TGA and DSC analyses, and their flammability resistances were evaluated by measuring their Limited Oxygen Index (LOI) and the UL-94V test. A multitude of flame retardant elements in the fabric samples increased the LOI values as much as 45 from 20 of the untreated LCNFs. Moreover, the morphology of both the NPCM-treated LCNFs and their burnt fabrics was studied with a scanning electron microscope (SEM). The heat release lowering effect of the LCNF fabric against the water-based paint was observed with a cone calorimeter. Furthermore, the mechanical properties represented as the tensile strength of the NPCM-treated LCNF fabrics revealed that the increase of the NPCM content in the PP-composites led to an increased bending strength with enhancing the flame-retardance.

DOI： 10.1039/d1ra08716a

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.dental.2021.10.009

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/d1ma00273b

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1177/0022034520979133

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その他リンク： http://journals.sagepub.com/doi/full-xml/10.1177/0022034520979133

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/jopr.13372

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4012/dmj.2020-029

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1089/ten.teb.2020.0352

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その他リンク： https://www.liebertpub.com/doi/pdf/10.1089/ten.teb.2020.0352

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1177/00220345211001020

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その他リンク： http://journals.sagepub.com/doi/full-xml/10.1177/00220345211001020

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/ma14061442

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.26502/acbr.50170191

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/ma13225099

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.msec.2020.111178

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsabm.0c00476

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.dental.2020.04.014

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/d0tb00079e

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41598-020-61111-1

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その他リンク： http://www.nature.com/articles/s41598-020-61111-1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1177/2280800020942717

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その他リンク： http://journals.sagepub.com/doi/full-xml/10.1177/2280800020942717

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.actbio.2019.09.045

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.actbio.2019.08.029

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jbm.a.36618

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4012/dmj.2017-397

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ceramint.2018.07.101

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

OBJECTIVES: Although the functional monomer glycero-phosphate dimethacrylate (GPDM) has since long been used in several dental adhesives and more recently in self-adhesive composite cements and restoratives, its mechanism of chemical adhesion to hydroxyapatite (HAp) is still unknown. We therefore investigated the chemical interaction of GPDM with HAp using diverse chemical analyzers and ultra-structurally characterized the interface of a GPDM-based primer formulation with dentin. METHODS: HAp particles were added to a GPDM solution for various periods, upon which they were thoroughly washed with ethanol and water prior to being air-dried. As control, 10-methacryloyloxydecyl dihydrogen phosphate (MDP) was used. The molecular interaction of GPDM with HAp was analyzed using X-ray diffraction (XRD) and solid-state nuclear magnetic resonance (NMR) spectroscopy. Crystal formation upon application of GPDM onto dentin was analyzed using thin-film XRD (TF-XRD). Its hydrophobicity was measured using contact-angle measurement. The interaction of GPDM with dentin was characterized using transmission electron microscopy (TEM). RESULTS: XRD revealed the deposition of dicalcium phosphate dihydrate (DCPD: CaHPO4·2H2O) on HAp after 24h. NMR confirmed the adsorption of GPDM onto HAp. However, GPDM was easily removed after washing with water, unlike MDP that remained adhered to HAp. Dentin treated with GPDM appeared more hydrophilic compared to dentin treated with MDP. TEM disclosed exposed collagen in the hybrid layer produced by the GPDM-based primer formulation. SIGNIFICANCE: Although GPDM adsorbed to HAp, it did not form a stable calcium salt. The bond between GPDM and HAp was weak, unlike the strong bond formed by MDP to HAp. Due to its high hydrophilicity, GPDM might be an adequate monomer for an etch-and-rinse adhesive, but appears less appropriate for a 'mild' self-etch adhesive that besides micro-retention ionically interacts with HAp, or for a self-adhesive restorative material.

DOI： 10.1016/j.dental.2018.04.003

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記述言語：日本語   出版者・発行元：(一社)日本骨代謝学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier Inc.  

Objective: To assess the influence of alumina sandblasting on four highly translucent dental zirconia grades. Methods: Fully sintered zirconia disk-shaped specimens (15-mm diameter
0.5-mm thickness) of four highly translucent yttria partially stabilized zirconia (Y-PSZ) grades (KATANA HT, KATANA STML, KATANA UTML, Kuraray Noritake
Zpex Smile, Tosoh) were sandblasted with 50-μm alumina (Al2O3) sand (Kulzer) or left ‘as-sintered’ (control) (n = 5). For each zirconia grade, the translucency was measured using a colorimeter. Surface roughness was assessed using 3D confocal laser microscopy, upon which the zirconia grades were statistically compared for surface roughness using a Kruskal–Wallis test (n = 10). X-ray diffraction (XRD) with Rietveld analysis was used to assess the zirconia-phase composition. Micro-Raman spectroscopy was used to assess the potentially induced residual stress. Results: The translucency of KATANA UTML was the highest (36.7 ± 1.8), whereas that of KATANA HT was the lowest (29.5 ± 0.9). The ‘Al2O3-sandblasted’ and ‘as-sintered’ zirconia revealed comparable surface-roughness Sa values. Regarding zirconia-phase composition, XRD with Rietveld analysis revealed that the ‘as-sintered’ KATANA UTML contained the highest amount of cubic zirconia (c-ZrO2) phase (71 wt%), while KATANA HT had the lowest amount of c-ZrO2 phase (41 wt%). KATANA STML and Zpex Smile had a comparable zirconia-phase composition (60 wt% c-ZrO2 phase). After Al2O3-sandblasting, a significant amount (over 25 wt%) of rhombohedral zirconia (r-ZrO2) phase was detected for all highly translucent zirconia grades. Significance: Al2O3-sandblasting did not affect the surface roughness of the three highly translucent Y-PSZ zirconia grades, but it changed its phase composition.

DOI： 10.1016/j.dental.2017.12.008

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

Biomineralization involves complex processes and interactions between organic and inorganic matters, which are controlled in part by the cells. The objectives of this study were, first, to perform a systematic and ultrastructural investigation of the initial mineral formation during secondary ossification center of mouse femur based on material science and biology viewpoint, and then develop novel biomaterials for mineralization based on the in vivo findings. First, we identified the very initial mineral deposition at postnatal day 5 (P5) at the medial side of femur epiphysis by nanocomputed tomography. Initial minerals were found in the surroundings of hypertrophic chondrocytes. Interestingly, histological and immunohistochemical analyses showed that initial mineralization until P6 was based on chondrocyte activity only, i.e., it occurred in the absence of osteoblasts. Moreover, electron microscopy-based ultrastructural analysis showed that cell-secreted matrix vesicles were absent in the early steps of osteoblast-independent endochondral ossification. Instead, chondrocyte membrane nanofragments were found in the fibrous matrix surrounding the hypertrophic chondrocytes. EDS analysis and electron diffraction study indicated that cell membrane nanofragments were not mineralized material, and could be the nucleation site for the newly formed calcospherites. The phospholipids in the cell membrane nanofragments could be a source of phosphate for subsequent calcium phosphate formation, which initially was amorphous, and later transformed into apatite crystals. Finally, artificial cell nanofragments were synthesized from ATDC5 chondrogenic cells, and in vitro assays showed that these nanofragments could promote mineral formation. Taken together, these results indicated that cell membrane nanofragments were the nucleation site for mineral formation, and could potentially be used as material for manipulation of biomineralization.

DOI： 10.1021/acsbiomaterials.7b00962

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

OBJECTIVE: To assess light irradiance (LI) delivered by two light-curing units (LCU's) and to measure the degree of conversion (DC) of three composite cements, when cured through different thicknesses of two novel CAD-CAM block materials. METHODS: 100-μm-thick films of a dual-curable composite cement (G-CEM LinkAce, GC), a light-curable flowable resin-based composite (RBC) (G-ænial Universal Flo, GC) and a micro-hybrid RBC (G-ænial Posterior, GC) were investigated as luting agents. Two 'polymer-ceramic' CAD-CAM blocks (Cerasmart, GC; Enamic, Vita Zahnfabrik) were sectioned in slabs with different thicknesses (1, 3 and 5mm). LI at the bottom of the specimens was measured using a calibrated spectrometer, while being light-cured through the CAD-CAM block slabs for 40s with a low- (±500mW/cm2) or high- (±1,600mW/cm2) irradiance LCU (n=5). After light-curing, micro-Raman spectra of the composite films were acquired to determine DC at 5min, 10min, 1h and 24h. LI data were statistically analyzed by Kruskal-Wallis followed by post-hoc comparisons, while a linear mixed-effect model was applied for the DC analysis. In addition, the CAD-CAM blocks ultrastructure was characterized upon argon-ion slicing using scanning transmission electron microscopy (STEM). Finally, light transmission (LT) through each CAD-CAM block material was assessed using a spectrophotometer. RESULTS: Curing-light attenuation and DC were significantly influenced by thickness and type of the overlying material. LCU only had a significant effect on DC of the micro-hybrid RBC. DC significantly increased over time for all composite cements. CAD-CAM block structural analysis revealed a relatively small and homogenous filler configuration (mean filler size of 0.2-0.5μm) for Cerasmart, while Enamic contained ceramic grains varying in shape and size (1-10μm), which were interconnected by the polymer-based network. LT was much higher at a wavelength range of 300-800nm for Cerasmart than for Enamic. SIGNIFICANCE: Light-curable composite cements can be cured through a restoration up to 2.7-mm thickness, depending on the kind of CAD-CAM material. A high-irradiance LCU only has a limited effect on the maximum thickness of the polymer-ceramic CAD-CAM material that can be cured through.

DOI： 10.1016/j.dental.2017.11.008

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Royal Society of Chemistry ({RSC})  

Analysis of tissue development from multidisciplinary approaches can result in more integrative biological findings, and can eventually allow the development of more effective bioengineering methods. In this study, we analyzed the initial steps of mineral formation during secondary ossification of mouse femur based on biological and bioengineering approaches. We first found that some chondrocytes burst near the mineralized area. External factors that could trigger chondrocyte burst were then investigated. Chondrocyte burst was shown to be modulated by mechanical and osmotic pressure. A hypotonic solution, as well as mechanical stress, significantly induced chondrocyte burst. We further hypothesized that chondrocyte burst could be associated with space-making for mineral expansion. In fact, ex vivo culture of femur epiphysis in hypotonic conditions, or under mechanical pressure, enhanced mineral formation, compared to normal culture conditions. Additionally, the effect of mechanical pressure on bone formation in vivo was investigated by immobilization of mouse lower limbs to decrease the body pressure onto the joints. The results showed that limb immobilization suppressed bone formation. Together, these results suggest chondrocyte burst as a novel fate of chondrocytes, and that manipulation of chondrocyte burst with external mechano-chemical stimuli could be an additional approach for cartilage and bone tissue engineering.

DOI： 10.1039/c7ib00130d

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DOI： 10.1177/0022034518763606

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

The collagen network acts as a scaffold for calcification and its three-dimensional structure influences bone strength. It is therefore important to observe the collagen network in detail and three-dimensionally. In this study, we observed the collagen network of chick embryonic calvariae in membranous bone three-dimensionally using orthogonally arranged FIB-SEM. A 25 x 25 mm area of chick embryonic calvaria was observed at a high resolution (25 nm per pixel). The inside of the bone (i.e. the primary calcified tissue), the bone cells (i.e. the osteoblasts and the osteocytes), the organelles, and the collagen fibrils were observed in detail. These structures were observed three-dimensionally using the Amira software program. In addition, the collagen fibrils of the bone were automatically extracted using the XTracing extension software program, and three-dimensional morphometry was performed. Almost all of the collagen fibrils ran along the longitudinal axis of the trabecular bone. We found that the regularity of the collagen fibril orientation was less remarkable in the osteoblast layer, which contained numerous osteoblasts. The collagen fibril orientation started to show regularity toward the central bone layer, which contained few bone cells.

DOI： 10.1039/c7ib00073a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

Leptothrix species produce microtubular organic-inorganic materials that encase the bacterial cells. The skeleton of an immature sheath, consisting of organic exopolymer fibrils of bacterial origin, is formed first, then the sheath becomes encrusted with inorganic material. Functional carboxyl groups of polysaccharides in these fibrils are considered to attract and bind metal cations, including Fe(III) and Fe(III)-mineral phases onto the fibrils, but the detailed mechanism remains elusive. Here we show that NH2 of the amino-sugar-enriched exopolymer fibrils is involved in interactions with abiotically generated Fe(III) minerals. NH2-specific staining of L. cholodnii OUMS1 detected a terminal NH2 on its sheath skeleton. Masking NH2 with specific reagents abrogated deposition of Fe(III) minerals onto fibrils. Fe(III) minerals were adsorbed on chitosan and NH2-coated polystyrene beads but not on cellulose and beads coated with an acetamide group. X-ray photoelectron spectroscopy at the N1s edge revealed that the terminal NH2 of OUMS1 sheaths, chitosan and NH2-coated beads binds to Fe(III)-mineral phases, indicating interaction between the Fe(III) minerals and terminal NH2. Thus, the terminal NH2 in the exopolymer fibrils seems critical for Fe encrustation of Leptothrix sheaths. These insights should inform artificial synthesis of highly reactive NH2-rich polymers for use as absorbents, catalysts and so on.

DOI： 10.1038/s41598-017-06644-8

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Objective. Bioactive glasses and surface pre-reacted glass-ionomer (sPRG) filler possess cario-static properties owing to ion release. Many studies investigated potential cariostatic effects; few studies evaluated the surface stability and the structural changes their surfaces undergo in acidic conditions.
Methods. The surface resistance against acid attack and the surface receptiveness for bacterial adhesion and biofilm formation of a sPRG-filled (Beautifil ll, Shofu) and conventional glass-filled (Herculite XRV Ultra, Kerr) resin-based composite (RBC), and a conventional glass-ionomer cement (GIC; Fuji IX GP Extra, GC) were examined. Specimens (n = 3) were immersed in distilled water or lactic acid (pH 4.0) for 3 days. Bacterial growth and biofilm formation were recorded using optical density and SEM.
Results. Upon 3-day immersion in lactic acid, the surface of the sPRG-filled RBC revealed multiple holes, while virtually no change in surface integrity was observed for the conventional RBC and GIC. Bacterial growth measurements revealed that none of the materials inhibited Streptococcus mutans (p<0.05). Remarkably, cross-sectional SEM revealed that S. mutans had penetrated the etch pits induced by lactic acid in/around the sPRG filler. Ion-release measurements revealed that sPRG-filled RBC released boron and fluoride, while GIC only released fluoride. However, the concentration of ions released by both materials appeared not sufficient to inhibit bacterial growth. Moreover, the structural surface change and resultant increased surface roughness appeared to have promoted biofilm formation.
Significance. While having bioactive potential through ion release, the stability of surface integrity of bioactive materials is a key-parameter to be assessed with regard to their cario-static potential. (C) 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.dental.2017.04.002

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Avestia Publishing  

Dental implants are highly effective for improving the occlusion function after tooth loss. However, ordinarily titanium dental implants sometimes require long term for the osseointegration. If there is insufficient bone in the patients, surgical pre-treatment such as autologous bone transplantation is required, imposing a big burden on the patient. Furthermore, a predominance of invasion of the gingival epithelium by epithelial cells at an early stage increases the risk of unsuccessful osseointegration. Therefore, to reduce the burden on the patient and increase the success rate of dental implant treatment, we need to develop a dental implant that can promote osseointegration more quickly and efficiently. We presumed that it would be one of efficient strategies for the quick and reliable osseointegration if we could control the cell population around the dental implant. Here, we micro-patterned a titanium surface by using a gelatin matrix. Mesenchymal stem cells were cultured, and cell populations were investigated. On the titanium surface with a micro-patterned gelatin matrix, mesenchymal stem cells first adhered to the titanium and then to the gelatin, enabling cell adhesion to be controlled time dependently. These results suggest that it may be possible to develop functional dental implants in which we can control the cell population of epithelial and mesenchymal stem cells and can promote quick and reliable osseointegration.

DOI： 10.11159/nddte17.111

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

Currently, the functional monomer 10-methacryloyloxy-decyl-dihydrogen-phosphate (10-MDP) was documented to chemically bond to zirconia ceramics. However, little research has been conducted to unravel the underlying mechanisms. This study aimed to assess the chemical interaction and to demonstrate the mechanisms of coordination between 10-MDP and zirconium oxide using H-1 and P-31 magic angle spinning (MAS) nuclear magnetic resonance (NMR) and two dimensional (2D) H-1 -> P-31 heteronuclear correlation (HETCOR) NMR. In addition, shear bond-strength (SBS) tests were conducted to determine the effect of 10-MDP concentration on the bonding effectiveness to zirconia. These SBS tests revealed a 10-MDP concentration-dependent SBS with a minimum of 1-ppb 10-MDP needed. P-31-NMR revealed that one P-OH non-deprotonated of the PO3H2 group from 10-MDP chemically bonded strongly to zirconia. H-1-P-31 HETCOR NMR indicated that the 10-MDP monomer can be adsorbed onto the zirconia particles by hydrogen bonding between the P=O and Zr-OH groups or via ionic interactions between partially positive Zr and deprotonated 10-MDP (P-O-). The combination of H-1 NMR and 2D H-1-P-31 HETCOR NMR enabled to describe the different chemical states of the 10-MDP bonds with zirconia; they not only revealed ionic but also hydrogen bonding between 10-MDP and zirconia.

DOI： 10.1038/srep45563

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Objective. CAD-CAM blocks to fabricate semi-direct and indirect restorations are available in different sorts of ceramics as well as composite. In order to bond restorations prepared out of composite blocks into tooth cavities, it is recommended to gently sandblast the surface prior to the application of a primer/adhesive. Today, the effect of sandblasting composite block surfaces has not thoroughly been investigated. In this study, the ultra-structure of composite CAD-CAM blocks was investigated with special attention to the effect of sandblasting on the surface topography and of silanization on the bonding performance.
Methods. Five different composite CAD-CAM blocks were involved. We correlatively investigated their structural and chemical composition using X-ray diffraction (XRD), energy dispersion spectroscopy (EDS), scanning electron microscopy (SEM) and (scanning) transmission electron microscopy ((S)TEM). The effect of sandblasting was also imaged in cross-section and at the interface with composite cement. Finally, we measured the shear bond strength to the sandblasted block surface with and without silanization.
Results. All composite blocks revealed a different ultra-structure. Sandblasting increased surface roughness and resulted in an irregular surface with some filler exposure. Sandblasting also damaged the surface. When the sandblasted composite blocks were silanized, superior bonding receptiveness in terms of higher bond strength was achieved except for Shofu Block HC.
Significance. Sandblasting followed by silanization improved the bond strength to composite CAD-CAM blocks. However, sandblasting may also damage the composite CAD-CAM block surface. For the composite CAD-CAM block Shofu Block HC, the damage was so severe that silanization did not improve bond strength. (C) 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.dental.2016.12.003

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DOI： 10.11159/ijtan.2017.003

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.dental.2016.07.002

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MDPI AG  

Species of the Fe/Mn-oxidizing bacteria Leptothrix produce tremendous amounts of microtubular, Fe/Mn-encrusted sheaths within a few days in outwells of groundwater that can rapidly clog water systems. To understand this mode of rapid sheath production and define the timescales involved, behaviors of sheath-forming Leptothrix sp. strain OUMS1 were examined using time-lapse video at the initial stage of sheath formation. OUMS1 formed clumps of tangled sheaths. Electron microscopy confirmed the presence of a thin layer of bacterial exopolymer fibrils around catenulate cells (corresponding to the immature sheath). In time-lapse videos, numerous sheath filaments that extended from the periphery of sheath clumps repeatedly fragmented at the apex of the same fragment, the fragments then aggregated and again elongated, eventually forming a large sheath clump comprising tangled sheaths within two days. In this study, we found that fast microscopic fragmentation, dissociation, re-aggregation and re-elongation events are the basis of the rapid, massive production of Leptothrix sheaths typically observed at macroscopic scales.

DOI： 10.3390/biology5030032

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記述言語：日本語   出版者・発行元：(公社)日本補綴歯科学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PUBLIC LIBRARY SCIENCE  

Background
Sandblasting particles which remain on the surfaces of dental restorations are removed prior to cementation. It is probable that adhesive strength between luting material and sandblasting particle remnants might exceed that with restorative material. If that being the case, blasting particles adhere to sandblasted material surface could be instrumental to increasing adhesive strength like underlying bonding mechanism between luting material and silanized particles of tribochemical silica coating-treated surface. We hypothesize that ultrasonic cleaning of bonding surfaces, which were pretreated with sandblasting, may affect adhesive strength of a resin luting material to dental restorative materials.
Methods
We therefore observed adhesive strength of resin luting material to aluminum oxide was greater than those to zirconia ceramic and cobalt-chromium alloy beforehand. To measure the shear bond strengths of resin luting material to zirconia ceramic and cobalt-chromium alloy, forty specimens of each restorative material were prepared. Bonding surfaces were polished with silicon abrasive paper and then treated with sandblasting. For each restorative material, 40 sandblasted specimens were equally divided into two groups: ultrasonic cleaning (USC) group and non-ultrasonic cleaning (NUSC) group. After resin luting material was polymerized on bonding surface, shear test was performed to evaluate effect of ultrasonic cleaning of bonding surfaces pretreated with sandblasting on bond strength.
Results
For both zirconia ceramic and cobalt-chromium alloy, NUSC group showed significantly higher shear bond strength than USC group.
Conclusions
Ultrasonic cleaning of dental restorations after sandblasting should be avoided to retain improved bonding between these materials.

DOI： 10.1371/journal.pone.0147077

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SAGE PUBLICATIONS INC  

The interfacial interaction of veneering ceramic with zirconia is still not fully understood. This study aimed to characterize morphologically and chemically the zirconia-veneering ceramic interface. Three zirconia-veneering conditions were investigated: 1) zirconia-veneering ceramic fired on sandblasted zirconia, 2) zirconia-veneering ceramic on as-sintered zirconia, and 3) alumina-veneering ceramic (lower coefficient of thermal expansion [CTE]) on as-sintered zirconia. Polished cross-sectioned ceramic-veneered zirconia specimens were examined using field emission gun scanning electron microscopy (Feg-SEM). In addition, argon-ion thinned zirconia-veneering ceramic interface cross sections were examined using scanning transmission electron microscopy (STEM)-energy dispersive X-ray spectrometry (EDS) at high resolution. Finally, the zirconia-veneering ceramic interface was quantitatively analyzed for tetragonal-to-monoclinic phase transformation and residual stress using micro-Raman spectroscopy (mu Raman). Feg-SEM revealed tight interfaces for all 3 veneering conditions. High-resolution transmission electron microscopy (HRTEM) disclosed an approximately 1.0-mu m transformed zone at sandblasted zirconia, in which distinct zirconia grains were no longer observable. Straight grain boundaries and angular grain corners were detected up to the interface of zirconia-and alumina-veneering ceramic with as-sintered zirconia. EDS mapping disclosed within the zirconia-veneering ceramic a few nanometers thick calcium/aluminum-rich layer, touching the as-sintered zirconia base, with an equally thick silicon-rich/aluminum-poor layer on top. mu Raman revealed t-ZrO2 -to-m-ZrO2 phase transformation and residual compressive stress at the sandblasted zirconia surface. The difference in CTE between zirconia-and the alumina-veneering ceramic resulted in residual tensile stress within the zirconia immediately adjacent to its interface with the veneering ceramic. The rather minor chemical elemental shifts recorded in the veneering ceramic did not suffice to draw definitive conclusions regarding potential chemical interaction of the veneering ceramic with zirconia. Sandblasting damaged the zirconia surface and induced phase transformation that also resulted in residual compressive stress. Difference in CTE of zirconia versus that of the veneering ceramic resulted in an unfavorable residual tensile stress at the zirconia-veneering ceramic interface.

DOI： 10.1177/0022034515608825

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Objective. The functional monomer 10-MDP has been considered as one of the best performing functional monomers for dental adhesives. Different adhesives containing 10-MDP are commercially available, among which many so-called 'universal' adhesives. We hypothesize that the quality of the functional monomer 10-MDP in terms of purity may affect bonding performance.
Methods. We therefore characterized three different 10-MDP versions (10-MDP_KN provided by Kuraray Noritake; 10-MDP_PCM provided by PCM; 10-MDP_DMI provided by DMI) using NMR, and analyzed their ability to form 10-MDP_Ca salts on dentin using XRD. The 'immediate' and 'aged' micro-tensile bond strength (mu TBS) to dentin of three experimental 10-MDP primers was measured. The resultant interfacial adhesive-dentin ultra-structure was characterized using TEM.
Results. NMR disclosed impurities and the presence of 10-MDP dimer in 10-MDP_PCM and 10-MDP_DMI. 10-MDP_PCM and 10-MDP_DMI appeared also sensitive to hydrolysis. 10-MDP_KN, on the contrary, contained less impurities and dimer, and did not undergo hydrolysis. XRD revealed more intense 10-MDP_Ca salt deposition on dentin induced by 10-MDP_KN. The adhesive based on the experimental 10-MDP_KN primer resulted in a significantly higher 'immediate' bond strength that remained stable upon aging; the mu TBS of the experimental 10-MDP_PCM and 10-MDP_DMI adhesives significantly dropped upon aging. TEM revealed thicker hybridization and more intense nano-layering for 10-MDP_KN.
Significance. It was concluded that primer impurities and the presence of 10-MDP dimer affected not only hybridization, but also reduced the formation of 10-MDP_Ca salts and nano-layering. 10-MDP in a high purity grade is essential to achieve durable bonding. (C) 2015 Published by Elsevier Ltd on behalf of Academy of Dental Materials. All rights reserved.

DOI： 10.1016/j.dental.2015.09.019

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE SOC DENTAL MATERIALS DEVICES  

The purpose of the present study was to evaluate the mechanical and chemical properties of a novel glass ionomer cement for use as a pit and fissure sealant containing a porous hydroxyapatite, namely, apatite ionomer cement (AIC). Control sealant samples were used Fuji III (GIC-S). The experiment sealant samples (AIC-S) consisted of porous spherical hydroxyapatite (HApS) particles added at 28 wt% to GIC-S powder. The GIC-S and AIC-S samples were evaluated through mechanical strength measurements, scanning electron microscopy observations, energy dispersive X-ray spectroscopy analysis, fluoride ion release tests, and antibacterial tests. The flexural strength of the AIC-S was significantly higher than that of GIC-S for each period, 1 h, 24 h and 1 year. The fluoride release dose for AIC-S was consistently higher than that for GIG-S. In addition, the antibacterial properties of AIC-S were superior to those of GIC-S. The novel AIC-S may be a more suitable sealant material for pits and fissures with intact and/or infected enamel.

DOI： 10.4012/dmj.2014-195

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE SOC DENTAL MATERIALS DEVICES  

Anodic oxidation is used for the surface treatment of commercial implants to improve their functional properties for clinical success. Here we conducted ultrastructural and chemical investigations into the micro- and nanostructure of the anodic oxide film of a titanium implant. The anodic oxidized layer of a Ti6Al4V alloy implant was examined ultrastructurally by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). They were also analyzed using energy dispersive X-ray spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS). The TEM revealed that the oxide layer of the Ti6Al4V implant prepared through anodic oxidation was separated into two layers. Al and V were not present on the top surface of the anodic oxide. This can be attributed to the biocompatibility of the anodic oxidized Ti6Al4V alloy implant, because the release of harmful metal ions such as Al and V can be suppressed by the biocompatibility.

DOI： 10.4012/dmj.2014-121

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記述言語：日本語   出版者・発行元：(公社)日本生物工学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SAGE PUBLICATIONS INC  

Among several functional monomers, 10-methacryloxydecyl dihydrogen phosphate (10-MDP) bonded most effectively to hydroxyapatite (HAp). However, more hydrolysis-resistant functional monomers are needed to improve bond durability. Here, we investigated the adhesive potential of the novel fluoro-carbon functional monomer 6-methacryloxy-2,2,3,3,4,4,5,5-octafluorohexyl dihydrogen phosphate (MF8P; Kuraray Noritake Dental Inc., Tokyo, Japan) by studying its molecular interaction with powder HAp using solid-state nuclear magnetic resonance (H-1 MAS NMR) and with dentin using x-ray diffraction (XRD) and by characterizing its interface ultrastructure at dentin using transmission electron microscopy (TEM). We further determined the dissolution rate of the MF8P_Ca salt, the hydrophobicity of MF8P, and the bond strength of an experimental MF8P-based adhesive to dentin. NMR confirmed chemical adsorption of MF8P onto HAp. XRD and TEM revealed MF8P_Ca salt formation and nano-layering at dentin. The MF8P_Ca salt was as stable as that of 10-MDP; MF8P was as hydrophobic as 10-MDP; a significantly higher bond strength was recorded for MF8P than for 10-MDP. In conclusion, MF8P chemically bonded to HAp. Despite its shorter size, MF8P possesses characteristics similar to those of 10-MDP, most likely to be associated with the strong chemical bond between fluorine and carbon. Since favorable bond strength to dentin was recorded, MF8P can be considered a good candidate functional monomer for bonding.

DOI： 10.1177/0022034513514447

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The term nanobacteria, sometimes referred to as nanobacteria-like particles (NLPs), is presently recognized as a misnomer for inert calcified nanoparticles. However, misinterpretation of its propagation as a living organism still continues. Ultrastructural and elemental analyses, combining immuno-electron microscopy with an original NLP isolate (P-17) derived from urinary stones, and an IgM monoclonal antibody (CL-15) raised against P-17 have now revealed that, oxidized lipids with acidified functional groups were key elements in NLP propagation. Lamellar structures composed of acidic/oxidized lipids provided structural scaffolds for carbonate apatite crystals. During in vitro culture, lipid peroxidation induced by gamma-irradiation of FBS was a major cause of accelerated NLP propagation. In pathological tissue samples from hyperlipidemic atherosclerosis-prone mice, CL-15 co-localized with fatty plaques, macrophage infiltrates and osteocalcin staining of aortic valve lesions. These observations indicate that naturally occurring NLP composed of mineralo-oxidized lipids complexes are generated as by-products rather than etiological agents of chronic inflammation. (C) 2014 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.nano.2013.08.010

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SOC BIOSCIENCE BIOENGINEERING JAPAN  

When constructing an in vitro model of liver tissue to mimic the in vivo liver microenvironment, the major challenge is to preserve and maintain the hepatocyte phenotype. The aim of this study was to develop a novel intelligent hybrid sponge for use in a dense co-culture system designed to simulate the liver microenvironment. We prepared a galactosylated chitosan (GCs)/hyaluronic acid (HA) hybrid sponge using a freeze-drying technique for the co-culture of primary hepatocytes and endothelial cells. Subsequently, we investigated the biocompatibility of the GCs/HA scaffold with primary hepatocytes and endothelial cells in terms of cell attachment, morphology, bioactivity, and maintenance of specific liver functions. The GCs/HA-hybrid sponge demonstrated good biocompatibility not only with primary hepatocytes, but also with endothelial cells. In our model, primary hepatocytes exhibited superior bioactivity and higher levels of liver-specific functions in terms of hepatocyte-specific gene expression, urea production, and testosterone metabolism as compared to a monoculture system. We succeeded in constructing a liver tissue-like model using the GCs/HA-hybrid sponge. Therefore, we anticipate that GCs/HA-hybrid sponges may be a promising matrix for the co-culture of hepatocytes and endothelial cells in liver tissue engineering, and might be employed as a novel co-culture model for applications in toxicology and drug metabolism. (C) 2013, The Society for Biotechnology, Japan. All rights reserved.

DOI： 10.1016/j.jbiosc.2013.06.015

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Objectives. The functional monomer 10-methacryloxydecyl dihydrogen phosphate (10-MDP), recently used in more self-etch adhesives, chemically bonds to hydroxyapatite (HAp) and thus tooth tissue. Although the interfacial interaction of the phosphoric-acid functional group of 10-MDP with HAp-based substrates has well been documented, the effect of the long carbon-chain spacer of 10-MDP on the bonding effectiveness is far from understood.
Methods. We investigated three phosphoric-acid monomers, 2-methacryloyloxyethyl dihydrogen phosphate (2-MEP), 6-methacryloyloxyhexyl dihydrogen phosphate (6-MHP) and 10-MDP, that only differed for the length of the carbon chain, on their chemical interaction potential with HAp and dentin, this correlatively using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Commercial 6-MHP and 10-MDP containing adhesives were investigated as well.
Results. XRD revealed that on HAp only 10-MDP produced monomer-calcium salts in the form of 'nano-layering', while on dentin all monomers produced 'nano-layering', but with a varying intensity in the order of 10-MDP > 6-MHP > 2-MEP. TEM confirmed that 10-MDP formed the thickest hybrid and adhesive layer. XRD and TEM revealed 'nano-layering' for all commercial adhesives on dentin, though less intensively for the 6-MHP containing adhesive than for the 10-MDP ones.
Significance. It is concluded that not only the phosphoric-acid group but also the spacer group, and its length, affect the chemical interaction potential with HAp and dentin. In addition, the relatively strong 'etching'' effect of 10-MDP forms more stable monomer-Ca salts, or 'nano-layering', than the two shorter carbon-chain monomers tested, thereby explaining, at least in part, the better bond durability documented with 10-MDP containing adhesives. (c) 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.dental.2013.05.006

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

We have designed and synthesized a new class of rhodamine dyes with an extended p-conjugated system and named them 3',3 ''-bis(oxospiroisobenzofuran)-3,7-bis(diethylamino) benzopyrano-xanthene (ABPX01) dyes. ABPX01 exhibits fluorescence emission in both dilute solution and the aggregate state, whereas conventional rhodamine dyes show aggregation-induced quenching (AIQ). The chemical species of ABPX01 in solution were determined by spectrophotometric measurements and density functional theory (DFT) calculations to study the relationship among chemical species, color, and fluorescence emission. ABPX01 has various forms: the spirolactone form (ABPX01(0)), which is colorless; and the monocationic form (ABPX01H(+)) and the dicationic form (ABPX01H(2)(2+)), which are colored. By orienting a pair of spirolactone benzene moieties differently, the stereoisomers of trans-and cis-ABPX01(0) were separated and their crystal structures determined. ABPX01H(2)(2+) was identified to be a red fluorescent species. Detailed spectroscopic and electron microscopic investigations led to the assumption that the ABPX01H(2)(2+) formed ion associates with Cl- as counter anions in HCl aqueous solution, and the nano-and submicrometer-sized colloidal aggregates of ABPX01 hydrochloride exhibit fluorescence emission. To further verify the aggregation-induced emission enhancement (AIEE) mechanism, ABPX01 hydrochloride was synthesized and its fluorescence was similarly checked in the powder state. AIEE in ABPX01 might be attributed to the synergistic combination of the restriction of dye-dye interaction induced dimer formation by sterically hindered ion associates and carboxylic benzene moieties, and the structural rigidity and intermolecular arrangement of the xanthene moiety. We expect that the design strategy of ABPX dyes will be extended to the development of a wide variety of functional organic-dye-based fluorophores (ODFs) with suitable fluorescence-emission controlled mechanisms for many useful applications in new electroluminescent devices.

DOI： 10.1039/c2cp43503a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SAGE PUBLICATIONS INC  

Previous research showed that the functional monomer 10-methacryloxydecyl dihydrogen phosphate (MDP) ionically bonds to hydroxyapatite (HAp) and forms a nano-layered structure at the interface with HAp-based substrates. Such hydrophobic nano-layering is considered to contribute to the long-term durability of the bond to tooth tissue. However, dental adhesives are complex mixtures usually containing different monomers. This study investigated the effect of the monomer 2-hydroxyethylmethacrylate (HEMA) on the chemical interaction of MDP with HAp by x-ray diffraction (XRD), nuclear magnetic resonance (NMR), and quartz crystal microbalance (QCM). We examined the chemical interaction of 5 experimental MDP solutions with increasing concentrations of HEMA. XRD revealed that addition of HEMA inhibits nano-layering at the interface, while NMR confirmed that MDP remained adsorbed onto the HAp surface. QCM confirmed this adsorption of MDP to HAp, as well as revealed that the demineralization rate of HAp by MDP was reduced by HEMA. It was concluded that even though the adsorption of MDP to HAp was not hindered, addition of HEMA inhibited interfacial nano-layering. Potential consequences with regard to bond durability necessitate further research.

DOI： 10.1177/0022034512460396

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記述言語：英語   出版者・発行元：WILEY-BLACKWELL  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE SOC DENTAL MATERIALS DEVICES  

According to the 'Adhesion-Decalcification' concept, specific functional monomers within dental adhesives can ionically interact with hydroxyapatite (HAp). Some specific functional monomers form monomer-Ca salts due to chemical interactions. The chemical stability of the monomer-Ca salts was thought to contribute to bond durability. In the present study, we analyzed the chemical interaction between an acidic three-dimensional self-reinforcing monomer (3D-SR) of Bond Force and enamel, dentin and HAp, and assessed its chemical stability by thin-film X-ray diffraction (TF-XRD). 3D-SR forms a hydrolysis-resistant Ca-salt on the dentin in a clinical application time period and on enamel and HAp in a longer time period. This suggests that the functional monomer 3D-SR is able to contribute to bond durability.

DOI： 10.4012/dmj.2012-074

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE SOC DENTAL MATERIALS DEVICES  

Titanium has an osseointegrative property, while hydroxyapatite has an osteoconductive property. It remains a matter of controversy among researchers whether hydroxyapatite has higher osteoblast compatibility than titanium. Here, we compared the activities between osteoblasts cultured on titanium and those cultured on hydroxyapatite. An osteoblast-like cell line, MC3T3-E1, was cultured on machined titanium, evaporated titanium, and hydroxyapatite disks to compare the affinity of osteoblasts to each of these materials. The adhesion and proliferation of MC3T3-E1 cells were higher on hydroxyapatite disks than on the other disks. Osteoblast differentiation was not affected by the nature of disks investigated, but calcium was more easily deposited on the hydroxyapatite disks. The amount of absorbed serum proteins detected on hydroxyapatite was greater than that on titanium. In conclusion, our results indicate hydroxyapatite is a more suitable material for osteoblast growth than titanium because of its higher absorption of serum proteins.

DOI： 10.4012/dmj.2012-075

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SAGE PUBLICATIONS INC  

According to the 'Adhesion-Decalcification' concept, specific functional monomers within dental adhesives can ionically interact with hydroxyapatite (HAp). Such ionic bonding has been demonstrated for 10-methacryloyloxydecyl dihydrogen phosphate (MDP) to manifest in the form of self-assembled 'nano-layering'. However, it remained to be explored if such nano-layering also occurs on tooth tissue when commercial MDP-containing adhesives (Clearfil SE Bond, Kuraray; Scotchbond Universal, 3M ESPE) were applied following common clinical application protocols. We therefore characterized adhesive-dentin interfaces chemically, using x-ray diffraction (XRD) and energy-dispersive x-ray spectroscopy (EDS), and ultrastructurally, using (scanning) transmission electron microscopy (TEM/STEM). Both adhesives revealed nano-layering at the adhesive interface, not only within the hybrid layer but also, particularly for Clearfil SE Bond (Kuraray), extending into the adhesive layer. Since such self-assembled nano-layering of two 10-MDP molecules, joined by stable MDP-Ca salt formation, must make the adhesive interface more resistant to biodegradation, it may well explain the documented favorable clinical longevity of bonds produced by 10-MDP-based adhesives.

DOI： 10.1177/0022034512437375

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Due to the high corrosion resistance and strength to density ratio titanium is widely used in industry, and also in a gamut of medical applications. Here we report for the first time on our development of a titanium passivation layer sensor that makes use of surface plasmon resonance (SPR). The deposited titanium metal layer on the sensor was passivated in air, similarly to titanium medical devices. Our "Ti-SPR sensor" enables analysis of biomolecule interactions with the passivated surface of titanium in real time. As a proof of concept, corrosion of a titanium passivation layer exposed to acid was monitored in real time. The Ti-SPR sensor can also accurately measure the time-dependence of protein adsorption onto the titanium passivation layer at sub-nanogram per square millimeter accuracy. Besides such SPR analyses, SPR imaging (SPRI) enables real time assessment of chemical surface processes that occur simultaneously at "multiple independent spots" on the Ti-SPR sensor, such as acid corrosion or adhesion of cells. Our Ti-SPR sensor will therefore be very useful to study titanium corrosion phenomena and biomolecular titanium-surface interactions with application in a broad range of industrial and biomedical fields. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.actbio.2011.11.025

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MOSHER & LINDER, INC  

Purpose: To clarify the effects of the addition of silanized (S) and unsilanized (U) spherical silica filler to resin-modified glass-ionomer cement and of powder-liquid ratio on (1) the early marginal gap-width of restorations in both tooth cavities and Teflon molds, (2) the gap-formation of restorations in Class V cavities, and (3) the compressive strength of the cement. Methods: Resin-modified glass-ionomer powder (Fuji II LC EM, GC) was modified by adding 5 and 10 wt% of powder respectively, of S and U, and then the powder-liquid ratio was increased up to 4.8. Human premolars, extracted for orthodontic reasons, were used for this study. Cylindrical cavities (1.5 mm deep, 3.5 mm in diameter; one cavity was prepared in each tooth in the coronal region and medial surface) were prepared in extracted human premolar teeth and restored with resin-modified glass-ionomer cements. Each restoration margin was inspected immediately after curing and polishing (as the immediate condition was the most severe), the maximum gap-width and the opposing width (if any) were determined microscopically (n= 10). An additional test was conducted in model Class V cavities. After finishing of restorations in model Class V cavities, each tooth was sectioned in a bucco-lingual direction through the center of the restoration, and the presence or absence of gaps along the cavity interface was evaluated (n=10). Additionally, the maximum marginal gap-width and the opposing-width along margins of restorations in cylindrical Teflon molds were measured (n= 10). The compressive strengths of the restorative materials were determined immediately after light-activation (n=10). Results: Marginal gap (tooth cavity: 0.32 to 0.25-0.20%, P< 0.05; Teflon cavity: 0.94 to 0.6-0.8%, P< 0.05) and cavity adaptation (no gap in the Class V: 22 to 40-50%, P< 0.05) of the restorations improved with increasing powder-liquid ratio (3.0 to 4.4-4.8) and compressive strength increased (111 to 150-170 MPa, P< 0.05). Highly significant correlation coefficients were found for the relationships between powder-liquid ratio and (1) percentage of marginal gap width in the tooth cavity (r= -0.96, P= 0.002, n= 6), (2) gap-free tooth/cement interfaces (r= 0.90, P= 0.015, n= 6), (3) percentage of marginal gap widths in the Teflon mold (i.= 0.98, P= 0.0004, n= 6) and (4) compressive strengths of the cements (r= 0.95, P= 0.004, n= 6). (Am J Dent 2011;24:310-314).

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

By a facile LiNO3 flux method, lithium manganese oxide composites (xLi(4)Mn(5)O(12)center dot yLi(2)MnO(3)) were synthesized using a hierarchical organization precursor of manganese dioxide. Li4Mn5O12 and Li2MnO3 have spinel and rocksalt structures, respectively. The lithiation and structural transformation from the precursor to the composites occurred topotactically from exterior toward interior in the precursor particle with the increase of reaction time, and the composites had core-shell spinel@rocksalt structures in addition to the original hierarchical core-shell organization. The electrochemical measurements at 50 degrees C after 50 cycles confirmed that a typical spinel@rocksalt cathode had higher capacity retention (87.1%) than that with the composition close to the stoichiometric spinel (64.6%), indicating the Li2MnO3 shell can improve cycling stability for the composite electrode at elevated temperature. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ssi.2011.06.005

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Following the "adhesion-decalcification" concept, specific functional monomers possess the capacity to primary chemically interact with hydroxyapatite (HAp). Such ionic bonding with synthetic HAp has been demonstrated for 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP), manifest as self-assembled "nanolayering". In continuation of that basic research this study aimed to explore whether nanolayering also occurs on enamel and dentin when a 10-MDP primer is applied following a common clinical application protocol. Therefore, the interaction of an experimental 10-MDP primer and a control, commercially available, 10-MDP-based primer (Clearfil SE Bond primer (C-SE), Kuraray) with enamel and dentin was characterized by X-ray diffraction (XRD), complemented with transmission electron microscopy interfacial ultrastructural data upon their reaction with enamel and dentin. In addition, XRD was used to study the effect of the concentration of 10-MDP on nanolayering on dentin. Finally, the stability of the nanolayers was determined by measuring the bond strength to enamel and dentin when a photoinitiator was added to the experimental primer or when interfacial polymerization depended solely on the photoinitiator supplied with the subsequently applied adhesive resin. XRD confirmed nanolayering on enamel and dentin, which was significantly greater on dentin than on enamel, and also when the surface was actively rubbed with the primer. Nanolayering was also proportional to the concentration of 10-MDP in the primer. Finally, the experimental primer needed the photoinitiator to obtain a tensile bond strength to dentin comparable with that of the control C-SE primer (which also contains a photoinitiator), but not when bonded to enamel. It is concluded that self-assembled nanolayering occurs on enamel and dentin, even when following a clinically used application protocol. The lower bonding effectiveness of mild self-etch adhesives to enamel should be ascribed in part to a lower chemical reactivity (nanolayering) with enamel HAP. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.actbio.2011.04.026

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SAGE PUBLICATIONS INC  

Previous research, in which the bonding effectiveness of the 3 self-etch monomers HAEPA, EAEPA, and MAEPA was determined, showed that MAEPA was most effective. In this study, the molecular interactions of these monomers with hydroxyapatite and dentin were investigated by combining x-ray diffraction, infrared spectroscopy, and scanning electron microscopy. We tested the null hypothesis that the bonding performance of these monomers does not correlate to the formation of monomer-calcium salts and to hydrolytic stability of these monomer-calcium complexes. Monomer/ethanol/water solutions were prepared and applied to synthetic hydroxyapatite and dentin. While HAEPA and EAEPA dissolved dentin considerably and deposited unstable calcium-phosphate salts (DCPD), MAEPA formed hydrolysis-resistant monomer-calcium salts that remained attached to the dentin surface even after being washed. The chemical stability of the monomer-Ca salts was thought to contribute in particular to the bond durability, but this study shows that the formation of stable monomer-calcium salts also enhances the 'immediate' bonding performance of self-etch adhesives.

DOI： 10.1177/0022034510397197

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DOI： 10.18939/jsdmd.30.1_63

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Although decayed/fractured teeth can be reconstructed minimally invasively and nearly invisibly using adhesive technology, the clinical longevity of dental composite restorations is still too short. Water sorption is thought to be the principal cause of destabilization of the biomaterial-tooth bond. However, the actual mechanisms of interfacial degradation are far from understood. Here we report how nano-controlled molecular interaction at the biomaterial-hard tissue interface can improve bond durability. The use of functional monomers with a strong chemical affinity for the calcium in hydroxyapatite is essential for long-term durability. Correlative X-ray diffraction and solid-state nuclear magnetic resonance disclosed a time-dependent molecular interaction at the interface with stable ionic bond formation of the monomer to hydroxyapatite competing in time with the deposition of less stable calcium phosphate salts. The advanced tooth-biomaterial interaction model gives not only an insight into the mechanisms of bond degradation, but also provides a basis to develop functional monomers for more durable tooth reconstruction. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.actbio.2010.03.024

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE SOC DENTAL MATERIALS DEVICES  

This study investigated the effects of spherical silica filler (SSF) on the workability and mechanical properties of resin-modified glass ionomer cements for luting (RMGICL). Varying powder/liquid ratios (P/L=2.0, 2.2, 2.4, and 2.6) of a commercially available glass ionomer cement (Fuji Lute, GC Corp.) were mixed with SSF at different weight percentages (5, 7.5, and 10%). On film thickness, statistically significant effects of SSF addition were noted at 2.5 minutes after mixing started, notably at P/L=2.4 and 2.6 when 7.5 and 10 wt% of SSF were added. The same result was also obtained for consistency evaluation. On mechanical and bonding strengths to the tooth substrate, no statistically significant differences were observed among all the SSF weight percentages within each P/L ratio. SSF-added RMGICL, at a higher powder/liquid ratio exhibited increased mechanical and bonding strengths when compared to a control without SSF addition, but nonetheless maintained the film thickness with no further increase.

DOI： 10.4012/dmj.2009-092

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SAGE PUBLICATIONS LTD  

Titanium and hydroxyapatite (HA) are widely used as biomaterials for dental and medical applications. HA-coated titanium implants have excellent biocompatibility and mechanical properties. However, the adherence of HA film formed on titanium substrate is weak because of the lack of chemical interaction between HA and titanium. A solution to this problem is to form an intermediate film on titanium substrate, which provide excellent adherence to both titanium substrate and HA. We developed a novel biomaterial called calcium titanate-amorphous carbon (CaTiO3-aC) coating prepared by modified thermal decomposition-method. The purpose of this study was to evaluate the effect of CaTiO3-aC and HA coating (positive control), and Ti (negative control) on osteoblastic (MT3T3-E1) cell responses. An increased cellular proliferation was observed in CaTiO3-aC coating compared to HA coating. The maximum expressions of ALP activity, Col I and ALP mRNA were higher and achieved in shorter period of time in CaTiO3-aC coating compared to others. These results demonstrated that CaTiO3-aC promoted better cell attachment, cellular proliferation, and osteoblastic differentiation compared with HA. In conclusion, we suggested that CaTiO3-aC could be considered as an important candidate as a coating material.

DOI： 10.1177/0885328209340334

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Objective. Biomaterials with anti-microbial properties are highly desirable in the oral cavity. Ideally, bactericidal molecules should be immobilized within the biomaterial to avoid unwanted side-effects against surrounding tissues. They may then however loose much of their antibacterial efficiency. The aim of this study was to investigate how much antibacterial effect an immobilized bactericidal molecule still has against oral bacteria.
Methods. Experimental resins containing 0, 1 and 3% cetylpyridinium chloride (CPC) were polymerized, and the bacteriostatic and bactericidal effects against Streptococcus mutans were determined. Adherent S. mutans on HAp was quantitatively determined using FE-SEM and living cells of S. mutans were quantified using real-time RT-PCR. The amount of CPC released from the 0%-, 1%- and 3%-CPC resin sample into water was spectrometrically quantified using a UV-vis recording spectrophotometer.
Results. UV spectrometry revealed that less than 0.11 ppm of CPC was released from the resin into water for all specimens, which is lower than the minimal concentration generally needed to inhibit biofilm formation. Growth of S. mutans was significantly inhibited on the surface of the 3%-CPC-containing resin coating, although no inhibitory effect was observed on bacteria that were not in contact with its surface. When immersed in water, the antibacterial capability of 3%-CPC resin lasted for 7 days, as compared to resin that did not contain CPC.
Significance. These results demonstrated that the bactericidal molecule still possessed significant contact bacteriostatic activity when it was immobilized in the resin matrix. (C) 2008 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.dental.2008.08.012

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JOURNAL HARD TISSUE BIOLOGY  

In the current study, we compared the recently developed CaTiO3-amorphous carbon (CaTiO3-aC) as a bone inducing coating material with HA from aspects of surface electric charge and solubility. CaTiO3-aC had negative surface electric charge similar to HA. Thus similar tissue reaction and bone inducing ability were considered to obtain.
On the other hand solubility of CaTiO3-aC coating was lower than HA. Moreover though CaTiO3-aC itself showed low solubility, CaCO3 was found to be included in it, and long-term slow Ca2+ release occurred. Thus the sample was suggested to be used as an ion exchange material.
When the implant using Ti/CaTiO3-aC/HA double layer coating was developed, first bioactive state of the implant will continue due to HA character. Then even early resorption of HA occurs, bioactive state will continue due to CaTiO3-aC layer. Therefore Ti base will not expose. This result is supposed to contribute long term success of the implant.

DOI： 10.2485/jhtb.17.115

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE SOC DENTAL MATERIALS DEVICES  

The purpose of this study was to evaluate how ultrasonic cleaning of silica-coated zirconia surfaces would influence the latter's bond strength to resin luting material. Forty zirconia specimens were divided into four groups: one air abrasion group and three silica-coated groups. Silica-coated specimens were cleaned with distilled water using an ultrasonic cleaner after tribochemical silica coating and then divided into three groups according to cleaning durations: I minute, 5 minutes, or without cleaning. Following which, resin luting material was polymerized against the specimens. After storage in water for 24 hours, the specimens were subjected to shear bond strength test. Shear bond strength of silica-coated group without cleaning was significantly higher than the other three groups, but there were no statistically significant differences among the three latter groups. SEM images suggested visible differences among the treatment methods. With EDXS analysis, it was revealed that ultrasonic cleaning decreased the silica content on the treated surfaces. Therefore, results showed that ultrasonic cleaning of tribochemically silica-coated zirconia surfaces decreased the adhesion efficacy to resin luting material.

DOI： 10.4012/dmj.27.842

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

PATIENT: An 83-year-old woman visited the hospital for new complete dentures. A mesh type stainless palatal plate (Trutissu plate) was selected, because it enables the patient to experience the taste and temperature of food. Twenty one months after insertion, the patient returned complaining of pain on mucosa under the mandibular denture base. On clinical examination, a small swollen area was observed on the palatine rugae region of the mesh plate. By making a small hole in the swollen part, a creamy mass of dark brown color was discharged from the swollen space between the laminated structure of the Trutissu plate. Three months after the first deformation was corrected, further deformation of the Trutissu plate was observed. The patient admitted that she had not used the ultrasonic cleansing apparatus. A candidiasis-like lesion was observed on the palatal mucosa. DISCUSSION: The formation of Candida biofilms on dentures may assist survival of fungal cells and contribute to the disease process in patients with denture stomatitis. In this case, the patient did not use ultrasonic cleaner, thus resulting in microbial accumulation and morphological change of the laminated mesh plate. However, this is rare in the clinical use of the Trutissu mesh plate, and the only case reported in 20 years. Ultrasonic cleansing was effective in removing microorganisms from the denture. CONCLUSION: Routine ultrasonic cleansing should be performed to avoid the possible accumulation of microorganisms in the laminated mesh structure.

DOI： 10.2186/jjps.52.555

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JOURNAL HARD TISSUE BIOLOGY  

We developed a novel method for titanium coating material using modified thermal decomposition technique, specifically focusing on presence of CaTiO3 and carbon C. Two layers of thin film coating composed of CaTiO3-amorphous carbon compound (CaTiO3-aC) and hydroxyapatite (HA) were generated on titanium surface. In this method, ratios of Ca/P as well as Ca/Ti, sintering temperature and sintering velocity were carefully planned. Within crystal structure of CaTiO3 granules, 4 atomic % of carbon in amorphous state was included. By our method, inclusion of carbon in HA suggested formation of carbonate apatite. Regarding with attachment-detachment experiment at titanium surface, adhesion strength was 2.5 times stronger in CaTiO(3)aC/FIA coating substrate as compared to HA only coating material. Results of the novel developed modified thermal decomposition method suggested that the 2 layers biomaterial composed of CaTiO3-aC (0.6 mu m) and carbonate apatite-included HA (2.4 mu m) can be used as a coating material on titanium surface.

DOI： 10.2485/jhtb.17.47

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記述言語：日本語  

DOI： 10.2320/jinstmet.70.897

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記述言語：英語   出版者・発行元：硬組織再生生物学会  

DOI： 10.2485/jhtb.14.309

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その他リンク： http://search.jamas.or.jp/link/ui/2007049575

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：INT SOC HISTOLOGY & CYTOLOGY  

Scanning electron microscopy (SEM) was employed to study the effect of calcitonin on the distribution of actin filaments in osteoclasts obtained from rat tibiae. Fluorescent microscopy was also applied to examine calcitonin-induced changes in the distribution of actin filaments, non-muscle myosin, M-Ras, and extracellular signal-regulated kinase (ERK) to clarify the role of ERK in the cytoskeleton of osteoclasts. SEM of control osteoclasts revealed a ring-like structure in the peripheral region. Labeled actin filaments and non-muscle myosin were detected in the peripheral region and exhibited a ring-like pattern. Immunoreactivity indicating M-Ras and ERK was also detected in the vicinity of the actin ring. After calcitonin treatment, many osteoclasts exhibited a retracted appearance and lacked a discernible actin ring. Numerous retraction fibers were found at the edge of calcitonin-treated osteoclasts. Actin filaments and non-muscle myosin were concentrated in the cytoplasm of calcitonin-treated osteoclasts, and exhibited a filamentous pattern. Labeled M-Ras and ERK also accumulated in the central region of these osteoclasts. These findings suggest that actin-myosin interaction plays an essential role in the retraction of osteoclasts induced by calcitonin. ERK may play a role in this interaction by activating myosin light chain kinase, as previously observed in smooth muscle cells.

DOI： 10.1679/aohc.68.143

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Immunohistochemistry for osteocalcin (OC) was performed on the rat vagal and glossopharyngeal sensory ganglia. OC-immunoreactive (IR) neurons were detected in the jugular (10%), petrosal (11%) and nodose ganglia (6%). The cell size analysis demonstrated that OC-IR neurons were predominantly small to medium-sized in the jugular ganglion (mean +/- S.D. = 356.3 +/- 192.2 mum(2), range = 86.5 - 831.5 mum(2)). On the other hand, such neurons were medium-sized to large in the petrosal (mean +/- S.D. = 725.6 +/- 280.7 mum(2), range = 124.7 - 1540.4 mum(2)) and nodose ganglia (mean +/- S.D. = 857.5 +/- 330.2 mum(2), range = 367.1 - 1608.0 mum(2)). In the circumvallate papilla, OC-IR nerve fibers were located in the vicinity of taste buds. Some taste bud cells were also immoureactive for the calcium-binding protein (CaBP). In the carotid body, however, OC-IR nerve fibers could not be detected. Retrograde tracing with fluorogold revealed that OC-IR nerve fibers in the circumvallate papilla mainly originated from the petrosal ganglion. These findings may suggest that OC-IR petrosal neurons have chemoreceptive function in the tongue. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.brainres.2004.10.011

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：OXFORD UNIV PRESS  

Histochemical, immunohistochemical and electron energy-loss spectroscopic studies were performed to examine the relationship between sulphated glycosaminoglycans and medullary bone calcification using oestrogen-injected male Japanese quail. Sulphated glycosaminoglycans, detected by high iron diamine (HID) or HID-thiocarbohydrazide-silver protein (HID-TCH-SP) methods, were distributed throughout the matrix of medullary bone, some periphery and extending tips of the trabeculae stained weakly, and the globular structures at osteoid areas were exclusively positive for HID-TCH-SP stain. Immunohistochemistry identified keratan sulphate located in the globular structures at osteoid areas and calcified matrix, but chondroitin-4 sulphate and chondroitin-6 sulphate were not detected in the matrix. Using electron spectroscopic imaging, sulphur was determined to be localized in the globular structures. These results demonstrate that medullary bone matrix accumulates keratan sulphate in the globular structures, which are the foci for calcification, and eventually in the calcified areas. This suggests that keratan sulphate containing sulphur is maintained in the calcified matrix. These results indicate a unique process of calcification exists in medullary bone.

DOI： 10.1093/jmicro/dfh097

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Immunohistochemistry for activated caspase-3 and terminal deoxynucleotidyl transferease-mediated dUTP-biotin nick end labeling (TUNEL) was performed on the trigeminal ganglion after infraorbital nerve transection in newborn rats. The injury induced caspase-3-immunoreactivity and DNA fragmentation in neuronal cell bodies in the maxillary division of the ganglion ipsilateral to the injury. Starting at 16 h post-injury the immunoreactive and TUNEL-positive neurons increased and reached the peak at 24 h (7.9% and 8.9%, respectively). Thereafter they decreased and returned to the normal control level (much less than1%) by 72 h. A double staining procedure revealed coexpression of caspasc-3-immunoreactivity and DNA fragmentation. 75.5% (114/151) of TUNEL-positive neurons expressed the immunoreactivity, while 84.4% (114/135) of immunoreactive neurons exhibited DNA fragmentation signal. These results suggest that caspase-3 plays an important role in apoptotic elimination of neonatally axotomized rodent primary neurons. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.brainres.2004.05.069

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記述言語：日本語   出版者・発行元：岡山歯学会  

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記述言語：英語   出版者・発行元：硬組織再生生物学会  

The morphology and characteristics of melanosomes are important features for differentiating melanocyte-derived melanotic lesions such as benign and malignant melanoma. There are two types of melanosome; eumelanin and pheomelanin. In this study, we attempted to elucidate the characteristics of melanosomes in malignant melanomas (melanotic type and amelanotic type) by ultrastructural analysis. In the melanotic type malignant melanoma in situ, pleomorphic and ellipsoid abnormal melanosomes, so-called eumelanin melanosomes, were detected, together with an increase in alkali elution rate. In the melanotic type invasive malignant melanoma, irregular ellipsoid and spheroid melanosomes were found either as discrete bodies or compound melanosomes, with further increase in alkali elution. In the amelanotic type malignant melanoma in situ, there were no melanosomes in atypical melanocytes and keratinocytes. In the amelanotic type invasive malignant melanoma, a few round melanosomes with low density matrix, so-called pheomelanin melanosomes, distributed in the cytoplasm. Our findings suggest that abnormal melanosome morphology and characteristics are predictive differential markers for the melanotic type or amelanotic type of oral malignant melanomas.

DOI： 10.2485/jhtb.13.87

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記述言語：日本語   出版者・発行元：(公社)日本補綴歯科学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The morphology and contents of melanosomes are important features for differentiating melanocyte-derived melanotic lesions such as melanosis and malignant melanoma. Methods: In this study, we attempted to elucidate the structure of melanin and sulphur content in oral melanosis and malignant melanomas by ultrastructural analysis. Results: In oral melanosis, the essential pathological findings were overproduction of eumelanin and discharge of melanin into keratinocytes. In malignant melanoma in situ, pleomorphic and ellipsoid abnormal melanosomes with an increase in sulphur content and alkali elution rate were detected. In invasive malignant melanoma, the irregular ellipsoid and spheroid melanosomes existing either as discrete bodies or compound melanosomes with furtherly increased sulphur content and alkali elution were detected. Conclusions: Our findings suggest that abnormal melanosome morphology and high sulphur content are predictive markers for assessment of early or precancerous melanotic lesions and malignant melanoma.

DOI： 10.1034/j.1600-0714.2002.00010.x

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記述言語：日本語   出版者・発行元：公益社団法人 日本顕微鏡学会  

DOI： 10.11410/kenbikyo1950.37.22

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掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1016/S0928-4680(00)00036-5

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記述言語：英語   出版者・発行元：日本硬組織研究技術学会  

We attempted to elucidate the characteristics of melanin in malignant melanomas in oral mucosa by ultrastructural and energy-filtering transmission electron microscopy to examie the morphology and sulfur contents of the melanins in oral lesions of benign melanosis and malignant melanonmas. In lesions of melanosis of the oral mucosa, the essential pathological features are over-production of eumelanin and migration of melanin into keratinocytes. In lesions of malignant melanoma in situ, abnormal melanosomes consisting of many pleomorphic and ellipsoid forms are present. Sulfur distribution is increased, showing an increase in pheomelanin-like melanin. In invasive malignant melanoma the melanosomes assume irregular ellipsoid and spheroid forms, with the presence of compound melanosomes. The contents are eluted by alkali and most contain sulfur, indicating marked increase of pheomelanin-like melanosomes. The morphology and properties of melanosomes are important differential features for melanocyte-derived melanotic lesions including benign tumor, melanosis, and malignant melanoma. These findings habe great significance in the interpretation of early or precancerous lesios.

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その他リンク： https://projects.repo.nii.ac.jp/?action=repository_uri&item_id=357319

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記述言語：日本語   出版者・発行元：(NPO)日本歯科保存学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(NPO)日本歯科保存学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本接着歯学会  

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記述言語：日本語   出版者・発行元：(一社)日本接着歯学会  

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記述言語：日本語   出版者・発行元：(NPO)日本歯科保存学会  

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記述言語：日本語   出版者・発行元：(NPO)日本歯科保存学会  

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記述言語：日本語   出版者・発行元：(一社)歯科基礎医学会  

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記述言語：日本語   出版者・発行元：(公社)日本補綴歯科学会  

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記述言語：日本語   出版者・発行元：(NPO)日本歯科保存学会  

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記述言語：日本語   出版者・発行元：(NPO)日本歯科保存学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(NPO)日本歯科保存学会  

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記述言語：日本語   出版者・発行元：(一社)日本接着歯学会  

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記述言語：日本語   出版者・発行元：(一社)日本接着歯学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)歯科基礎医学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(NPO)日本歯科保存学会  

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記述言語：日本語   出版者・発行元：(公社)日本補綴歯科学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本接着歯学会  

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記述言語：日本語   出版者・発行元：(一社)日本接着歯学会  

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記述言語：日本語   出版者・発行元：(一社)日本接着歯学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本接着歯学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：日本語   出版者・発行元：一般社団法人日本歯科理工学会  

Carrier materials with sensor for drug concentration hold great promise as smart delivery systems for drugs which have strong side effects, such as anticancer agents and bactericides. However, any carriers sensing drug concentration have not been turned to practical use. We found that the phosphopullulan and CPC complex changed their interaction at critical micelle concentration of CPC with phosphopullulan. It was also revealed that this phenomenon strongly related the bactericidal effects of the complex.

DOI： 10.14832/gsjsdmd.2010f.0.29.0

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記述言語：日本語   出版者・発行元：一般社団法人日本歯科理工学会  

To effectively exploit the properties of antibacterial agents, we synthesized phosphorylated polysaccharides as the carrier for bactericide delivery to surface of apatitic substrates. It was indicated that 0.01% phosphorylated pullulan and 0.01% cetylpyridinium chloride (CPC) consistently exhibited an antibacterial effect, even after rinsing with distilled water, although CPC at a concentration of 10% showed no effect on bacterial growth after slight rinsing.

DOI： 10.14832/gsjsdmd.2009f.0.30.0

CiNii Article

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

DOI： 10.14832/gsjsdmd.2009s.0.39.0

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記述言語：日本語   出版者・発行元：(一社)日本歯科理工学会  

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記述言語：英語   出版者・発行元：硬組織再生生物学会  

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記述言語：英語   出版者・発行元：硬組織再生生物学会  

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記述言語：英語  

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その他リンク： http://search.jamas.or.jp/link/ui/2003295956

記述言語：英語   出版者・発行元：特定非営利活動法人日本臨床口腔病理学会  

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記述言語：日本語   出版者・発行元：一般社団法人日本物理学会  

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記述言語：日本語   出版者・発行元：一般社団法人日本物理学会  

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記述言語：日本語   出版者・発行元：一般社団法人日本物理学会  

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開催年月日： 2022年11月4日 - 2022年11月5日

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記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2020年

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開催年月日： 2020年

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開催年月日： 2020年

記述言語：日本語  

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