We previously studied the mechanism underlying the adsorption of oral bacteria on the surfaces of dental prosthetic materials such as ceramics and resins in vitro. The aim of the present study was to examine bovine se...We previously studied the mechanism underlying the adsorption of oral bacteria on the surfaces of dental prosthetic materials such as ceramics and resins in vitro. The aim of the present study was to examine bovine serum albumin (BSA) adsorption on crown composite resin surfaces by means of zeta potential. We measured the zeta potentials of resins alone, BSA alone, and resins after BSA adsorption. Eight resins were pulverized into powders (300 - 1000 nm). All experiments were conducted in 10 mM sodium chloride solution (pH 6.5). BSA was dissolved in 10 mM NaCl with a concentration of 2.0 × 10-5 mol/l. An adsorption assay was performed for one hour at 37°C under continuous rotation (6 rpm). The zeta potentials of both resins and BSA were negative, with BSA itself less negative than the resins themselves as an absolute value (p < 0.0001). The zeta potentials of seven resin surfaces after BSA adsorption were significantly less negative than were those of the resins without BSA adsorption (p < 0.0001). Eight resins were divided into two classes based on the size of the surface potential difference between each resin and the BSA. The difference in surface potential between the resins and the BSA were small, leading to the theory that particles with identical charges repulse each other, and the amounts of adsorbed BSA on these resins might be less. On the other, when the differences between the other resins and BSA are large, so that the repulsive force between two nonidentical particles becomes zero and an attractive force might be generated, then more BSA might be adsorbed on those resins. Therefore, the zeta potentials were affected by BSA adsorption and became less negative. These results suggested that electrostatic interactions play an important role in the adsorption of BSA on resin surfaces.展开更多
The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction b...The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune–bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNAsequencing analysis on mouse periodontal lesions and showed that neutrophil–osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk.展开更多
The aim of this study was to identify the potential antibacterial effects of gatifloxacin on periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingi-valis, and Prevotella intermedia....The aim of this study was to identify the potential antibacterial effects of gatifloxacin on periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingi-valis, and Prevotella intermedia. The minimum inhibitory concentrations (MIC) of gatifloxacin and its bactericidal effects were investigated. Gatifloxacin inhibited the growth of all three kinds of periodontopathic bacteria tested in broth. The MIC value of 2.5 nM was found to be the most effective in inhibiting A. actinomycetemcomitans. An adenosine triphosphate biolumi-nescence assay revealed that gatifloxacin exhibited bactericidal effects on the tested bacteria in a time-dependent manner. The safety of gatifloxacin in mammalian cells was evaluated by assessing the viability of normal human dermal fibroblast (NHDF) cells treated with gatifloxacin. Almost all NHDF cells survived after 2-d culture, while 81% of the cells survived after 4-d culture when treated with 1.0 × 10<sup>3</sup> nM gatifloxacin. These results indicate that gatifloxacin is a possible drug for local administration to prevent periodontal infection.展开更多
Aims and Objectives: The purpose of this study was to investigate the influence of a titanium implant on immune response in mouse by monitoring change in plasma cytokine profiles. Materials and Methods: C57BL/6 (type ...Aims and Objectives: The purpose of this study was to investigate the influence of a titanium implant on immune response in mouse by monitoring change in plasma cytokine profiles. Materials and Methods: C57BL/6 (type 1 T helper cell-predominant) and BALB/c (type 2 T helper cell-predominant) mice were used. Each type was divided into an experimental and a control group: in the former, pure titanium implants (Φ 1 mm × 1 mm) were inserted into the back of the mice subcutaneously;in the latter, the wound was sutured closed with no insertion of an implant. Blood samples were collected before implantation and at 3 hr, 24 hr, 3 d, 1 mo, and 3 mo after implantation. Levels of IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, IL-17A, IL-23, IFN-γ, TNF-α, and TGF-β1 were measured by multi-analyte enzyme-linked immunosorbent assay. Results: Baseline cytokine levels were generally higher in the BALB/c mice than in their C57BL/6 counterparts. Cytokine levels showed only slight variation after implantation of titanium in ei-ther strain. No statistically significant differences in cytokine levels were detected, except for those of IL-6 and IL-10. Conclusion: The results showed that titanium implantation induced no clear Th1-, Th2-, or Th17-mediated immune response in either Th1-or Th2-predominant mice.展开更多
The debridement treatments of dental implants are very important in long-term maintenance after implant placement in a patient. Deposition of periodontal pathogens around the implant surface has a high risk of causing...The debridement treatments of dental implants are very important in long-term maintenance after implant placement in a patient. Deposition of periodontal pathogens around the implant surface has a high risk of causing periimplantitis. The aim of this study was to evaluate the extent of elimination of Porphyromonas gingivalis, known as representative periodontopathic bacteria, from titanium, which has been the main material used for dental implants. Assuming that the debridement processing of dental implants removes periodontal bacteria, one of the methods for removing bacteria deposited on titanium is considered to be plasma irradiation. Irradiation with atmospheric-pressure plasma was carried out against periodontopathic bacteria cultured and deposited on the surface of a titanium disk. After the plasma irradiation, the reduction of the number of bacteria re-cultured for 24 hours was evaluated. The number of viable bacteria on the titanium surface was estimated by an ATP-bioluminescent assay. Viable cells after the plasma irradiation were reduced to 1.5% or less compared to the untreated group. As one of the methods of debridement in general dental treatments, atmospheric-pressure plasma has proved to be an effective method to remove adverse prognostic factors in dental patients.展开更多
Newly synthesized membrane and secretory proteins in cells undergo folding in the endoplasmic reticulum with the introduction of disulfide bonds and acquire the correct three-dimensional structure. Disulfide bonds are...Newly synthesized membrane and secretory proteins in cells undergo folding in the endoplasmic reticulum with the introduction of disulfide bonds and acquire the correct three-dimensional structure. Disulfide bonds are especially important for protein folding. It has been thought that formation of protein disulfide bonds in eukaryotes is mainly carried out by an enzyme called protein disulfide isomerase. Proteins, bearing the C-terminus of amino acids sequences with His-Asp-Glu-Leu (HDEL) sequence in yeast, in the endoplasmic reticulum (ER), which is a eukaryotic cellular organelle involved in protein synthesis, processing, and transport, have been considered to recycle between ER and Golgi apparatus. The proposal for this recycling model derives from the study of an HDEL-tagged fusion protein. Here, the localization and oligosaccharide modification of protein disulfide isomerase were investigated in yeast, and showed the first direct evidence that this intrinsic ER protein transports from ER to Golgi. Results suggest that this native protein is also accessible to post-ER enzymes, and yet accumulates in the ER.展开更多
The aim of this study was to identify the potential antibacterial effects of gatifloxacin on one of canine periodontal pathogens, Porphyromonas gulae. The minimum inhibitory concentrations (MIC) of gatifloxacin and it...The aim of this study was to identify the potential antibacterial effects of gatifloxacin on one of canine periodontal pathogens, Porphyromonas gulae. The minimum inhibitory concentrations (MIC) of gatifloxacin and its bactericidal effects were investigated. Gatifloxacin inhibited the growth of the canine periodontopathic bacteria tested in broth. An MIC of 50 nM was found to be effective in inhibiting P. gulae. On performing adenosine triphosphate bioluminescence assay, gatifloxacin was found to exhibit bactericidal effects on the tested bacteria in a concentration-dependent manner. The safety of gatifloxacin in mammalian cells was evaluated by assessing the viability of rat bone marrow mesenchymal stem (BMMS) cells treated with gatifloxacin. Almost over 80% of BMMS cells survived after a 3-day culture when treated with 100 nM of gatifloxacin. These results indicate that locally administered gatifloxacin has the potential for being used to prevent canine periodontal infection.展开更多
文摘We previously studied the mechanism underlying the adsorption of oral bacteria on the surfaces of dental prosthetic materials such as ceramics and resins in vitro. The aim of the present study was to examine bovine serum albumin (BSA) adsorption on crown composite resin surfaces by means of zeta potential. We measured the zeta potentials of resins alone, BSA alone, and resins after BSA adsorption. Eight resins were pulverized into powders (300 - 1000 nm). All experiments were conducted in 10 mM sodium chloride solution (pH 6.5). BSA was dissolved in 10 mM NaCl with a concentration of 2.0 × 10-5 mol/l. An adsorption assay was performed for one hour at 37°C under continuous rotation (6 rpm). The zeta potentials of both resins and BSA were negative, with BSA itself less negative than the resins themselves as an absolute value (p < 0.0001). The zeta potentials of seven resin surfaces after BSA adsorption were significantly less negative than were those of the resins without BSA adsorption (p < 0.0001). Eight resins were divided into two classes based on the size of the surface potential difference between each resin and the BSA. The difference in surface potential between the resins and the BSA were small, leading to the theory that particles with identical charges repulse each other, and the amounts of adsorbed BSA on these resins might be less. On the other, when the differences between the other resins and BSA are large, so that the repulsive force between two nonidentical particles becomes zero and an attractive force might be generated, then more BSA might be adsorbed on those resins. Therefore, the zeta potentials were affected by BSA adsorption and became less negative. These results suggested that electrostatic interactions play an important role in the adsorption of BSA on resin surfaces.
基金supported in part by the Japan Agency for Medical Research and Development (AMED) under grant number JP20ek0410073, JP23ek0410108, JP22ek0410100, AMEDCREST under grant number JP19gm1210008 and AMED-PRIME under grant number JP21gm6310029, the AMED Japan Initiative for World leading Vaccine Research and Development Centers (JP223fa627001)Japan Society for the Promotion of Science (JSPS): Scientific Research S (21H05046), Scientific Research B (21H03104, 22H03195, and 22H02844) and Challenging Research (20K21515 and 21K18254)+3 种基金the JST FOREST Program (JPMJFR2261, JPMJFR205Z)Y.A. was supported by a JSPS Research Fellowship for Young Scientists (23KJ1949)Japanese Society for Immunology (JSI)Kibou Scholarship for Doctoral Students in Immunology。
文摘The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune–bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNAsequencing analysis on mouse periodontal lesions and showed that neutrophil–osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk.
文摘The aim of this study was to identify the potential antibacterial effects of gatifloxacin on periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingi-valis, and Prevotella intermedia. The minimum inhibitory concentrations (MIC) of gatifloxacin and its bactericidal effects were investigated. Gatifloxacin inhibited the growth of all three kinds of periodontopathic bacteria tested in broth. The MIC value of 2.5 nM was found to be the most effective in inhibiting A. actinomycetemcomitans. An adenosine triphosphate biolumi-nescence assay revealed that gatifloxacin exhibited bactericidal effects on the tested bacteria in a time-dependent manner. The safety of gatifloxacin in mammalian cells was evaluated by assessing the viability of normal human dermal fibroblast (NHDF) cells treated with gatifloxacin. Almost all NHDF cells survived after 2-d culture, while 81% of the cells survived after 4-d culture when treated with 1.0 × 10<sup>3</sup> nM gatifloxacin. These results indicate that gatifloxacin is a possible drug for local administration to prevent periodontal infection.
文摘Aims and Objectives: The purpose of this study was to investigate the influence of a titanium implant on immune response in mouse by monitoring change in plasma cytokine profiles. Materials and Methods: C57BL/6 (type 1 T helper cell-predominant) and BALB/c (type 2 T helper cell-predominant) mice were used. Each type was divided into an experimental and a control group: in the former, pure titanium implants (Φ 1 mm × 1 mm) were inserted into the back of the mice subcutaneously;in the latter, the wound was sutured closed with no insertion of an implant. Blood samples were collected before implantation and at 3 hr, 24 hr, 3 d, 1 mo, and 3 mo after implantation. Levels of IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, IL-17A, IL-23, IFN-γ, TNF-α, and TGF-β1 were measured by multi-analyte enzyme-linked immunosorbent assay. Results: Baseline cytokine levels were generally higher in the BALB/c mice than in their C57BL/6 counterparts. Cytokine levels showed only slight variation after implantation of titanium in ei-ther strain. No statistically significant differences in cytokine levels were detected, except for those of IL-6 and IL-10. Conclusion: The results showed that titanium implantation induced no clear Th1-, Th2-, or Th17-mediated immune response in either Th1-or Th2-predominant mice.
文摘The debridement treatments of dental implants are very important in long-term maintenance after implant placement in a patient. Deposition of periodontal pathogens around the implant surface has a high risk of causing periimplantitis. The aim of this study was to evaluate the extent of elimination of Porphyromonas gingivalis, known as representative periodontopathic bacteria, from titanium, which has been the main material used for dental implants. Assuming that the debridement processing of dental implants removes periodontal bacteria, one of the methods for removing bacteria deposited on titanium is considered to be plasma irradiation. Irradiation with atmospheric-pressure plasma was carried out against periodontopathic bacteria cultured and deposited on the surface of a titanium disk. After the plasma irradiation, the reduction of the number of bacteria re-cultured for 24 hours was evaluated. The number of viable bacteria on the titanium surface was estimated by an ATP-bioluminescent assay. Viable cells after the plasma irradiation were reduced to 1.5% or less compared to the untreated group. As one of the methods of debridement in general dental treatments, atmospheric-pressure plasma has proved to be an effective method to remove adverse prognostic factors in dental patients.
文摘Newly synthesized membrane and secretory proteins in cells undergo folding in the endoplasmic reticulum with the introduction of disulfide bonds and acquire the correct three-dimensional structure. Disulfide bonds are especially important for protein folding. It has been thought that formation of protein disulfide bonds in eukaryotes is mainly carried out by an enzyme called protein disulfide isomerase. Proteins, bearing the C-terminus of amino acids sequences with His-Asp-Glu-Leu (HDEL) sequence in yeast, in the endoplasmic reticulum (ER), which is a eukaryotic cellular organelle involved in protein synthesis, processing, and transport, have been considered to recycle between ER and Golgi apparatus. The proposal for this recycling model derives from the study of an HDEL-tagged fusion protein. Here, the localization and oligosaccharide modification of protein disulfide isomerase were investigated in yeast, and showed the first direct evidence that this intrinsic ER protein transports from ER to Golgi. Results suggest that this native protein is also accessible to post-ER enzymes, and yet accumulates in the ER.
文摘The aim of this study was to identify the potential antibacterial effects of gatifloxacin on one of canine periodontal pathogens, Porphyromonas gulae. The minimum inhibitory concentrations (MIC) of gatifloxacin and its bactericidal effects were investigated. Gatifloxacin inhibited the growth of the canine periodontopathic bacteria tested in broth. An MIC of 50 nM was found to be effective in inhibiting P. gulae. On performing adenosine triphosphate bioluminescence assay, gatifloxacin was found to exhibit bactericidal effects on the tested bacteria in a concentration-dependent manner. The safety of gatifloxacin in mammalian cells was evaluated by assessing the viability of rat bone marrow mesenchymal stem (BMMS) cells treated with gatifloxacin. Almost over 80% of BMMS cells survived after a 3-day culture when treated with 100 nM of gatifloxacin. These results indicate that locally administered gatifloxacin has the potential for being used to prevent canine periodontal infection.
