Publications by authors named "Kumiko Nakai"

Sodium fluoride (NaF) is a fluoride application recommended by the World Health Organization for its efficacy and safety in preventing dental caries. Gingival fibroblasts that constitute the majority of connective tissue cells play a major role in wound healing via the expression of growth factors, including fibroblast growth factor-2 (FGF-2) and transforming growth factor-beta (TGF-β). This study examined the effect of NaF mouthwash on FGF-2 and TGF-β expression in human gingival fibroblasts (HGnFs).

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Electric-toothbrush vibrations, which remove plaque, are transmitted to the gingival connective tissue via epithelial cells. Physical energy affects cell function; however, the effects of electric-toothbrush vibrations on gingival extracellular matrix (ECM) protein expression remain unknown. We aimed to examine the effects of these vibrations on the expression of ECM proteins-type I collagen (col I), type III collagen (col III), elastin, and fibronectin (FN)-using human gingival fibroblasts (HGnFs).

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Azithromycin displays immunomodulatory and anti-inflammatory effects in addition to broad-spectrum antimicrobial activity and is used to treat inflammatory diseases, including respiratory and odontogenic infections. Few studies have reported the effect of azithromycin therapy on bone remodeling processes. The aim of this study was to examine the effects of azithromycin on the osteogenic function of osteoblasts using osteoblast-like MC3T3-E1 cells.

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This study aimed to determine whether a dental health education program would reduce cardiometabolic risk (obesity, hypertension, dyslipidemia, and hyperglycemia) in people with periodontitis. We used annual check-up data provided by the Japanese company's health insurance union. Of 182 male employees with cardiometabolic risk and periodontal pockets at baseline, 21 participants of the dental health education program and 21 non-participants matched for age, the presence of obesity, and periodontal pocket at baseline were allocated to the intervention (mean age, 53.

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Objective: The remodeling of the vascular network and collagen in the extracellular matrix is closely associated with the expansion and dysfunction of adipose tissue. In the present study, we investigated the effects of interleukin (IL)-6 and tumor necrosis factor (TNF)-α on the expression of angiogenic factors, collagen, and collagenase and its endogenous inhibitor in premature and mature adipocytes.

Methods: Premature and mature adipocytes were differentiated from 3T3-L1 cells and stimulated with IL-6 or TNF-α to mimic the early and late phases of obesity development.

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BACKGROUND The interplay between obesity and periodontitis has been widely examined. While obesity was reported as a risk factor for periodontitis, the inverse relationship is still little explored. Therefore, we aimed to determine whether periodontitis and toothbrushing frequency affect the onset of obesity.

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BACKGROUND Osteoclast precursor cells are constitutively differentiated into mature osteoclasts on bone tissues. We previously reported that the continuous stimulation of RAW264.7 precursor cells with compressive force induces the formation of multinucleated giant cells via receptor activator of nuclear factor kappaB (RANK)-RANK ligand (RANKL) signaling.

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Aims: During orthodontic treatment, facilitating osteoclastic bone resorption in the alveolar bone exposed to the compressive force (CF) is an important factor for tooth movement. The present study investigated the effect of CF stimulation on the differentiation of RAW264.7 cells from precursors to mature osteoclasts.

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The association between obesity and inflammation is well documented in epidemiological studies. Proteolysis of extracellular matrix (ECM) proteins is involved in adipose tissue enlargement, and matrix metalloproteinases (MMPs) collectively cleave all ECM proteins. Here, we examined the effects of C-reactive protein (CRP), an inflammatory biomarker, on the expression of MMPs and tissue inhibitors of metalloproteinases (TIMPs), which are natural inhibitors of MMPs, in adipocyte-differentiated 3T3-L1 cells.

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Background: Epidemiological studies have reported that periodontitis and cardiometabolic disease such as cardiovascular disease and type 2 diabetes are associated; however, there have been very few prospective cohort studies on this topic. Therefore, we conducted a 9-year follow-up study to examine the relationship between the duration of periodontitis and cardiometabolic risk factors, including hypertension, hyperglycemia, dyslipidemia, and obesity.

Methods: The study participants comprised 572 adult industrial workers (417 men and 155 women; mean age, 37.

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Objective: Matrix metalloproteinases (MMPs), produced by osteoblasts, catalyze the turnover of extracellular matrix (ECM) molecules in osteoid, and the regulation of MMP activity depends on interactions between MMPs and tissue inhibitors of metalloproteinases (TIMPs). We focused on the degradation process of ECM in osteoid that was exposed to mechanical strain, and conducted an in vitro study using MC3T3-E1 osteoblastic cells to examine the effects of tension force (TF) on the expression of MMPs and TIMPs, and activation of mitogen-activated protein kinase (MAPK) pathways.

Design: Cells were incubated on flexible-bottomed culture plates and stimulated with or without cyclic TF for 24 hours.

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Introduction: Angiotensin II (Ang II) not only regulates systemic blood pressure through a vasoconstrictive effect, but also promotes bone resorption. We recently reported that Ang II (10(-6) M) stimulated the production of matrix metalloproteinases via the AT1 receptor in osteoblastic ROS17/2.8 cells, but suppressed alkaline phosphatase activity.

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Tobacco smoking is an important risk factor for the development of several cancers, osteoporosis, and inflammatory diseases such as periodontitis. Nicotine is one of the major components of tobacco. In previous study, we showed that nicotine inhibits mineralized nodule formation by osteoblasts, and the culture medium from osteoblasts containing nicotine and lipopolysaccharide increases osteoclast differentiation.

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Angiotensin II (Ang II) plays an important role in the maintenance of bone mass and integrity by activation of the mitogen-activated protein kinases (MAPKs) and by modulation of balance between resorption by osteoclasts and formation by osteoblasts. However, the role of Ang II in the turnover of extracellular matrix (ECM) in osteoid by osteoblasts remains unclear. Therefore, we examined the effect of Ang II on the expression of matrix metalloproteinases (MMPs), plasminogen activators (PAs), and their inhibitors [i.

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Intestinal microfold cells (M cells) are an enigmatic lineage of intestinal epithelial cells that initiate mucosal immune responses through the uptake and transcytosis of luminal antigens. The mechanisms of M-cell differentiation are poorly understood, as the rarity of these cells has hampered analysis. Exogenous administration of the cytokine RANKL can synchronously activate M-cell differentiation in mice.

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Article Synopsis
  • The study found that continual exposure to Gram-negative bacteria led to earlier stroke onset in stroke-prone hypertensive rats compared to controls.
  • During stroke onset, observable symptoms like hindlimb paralysis and changes in movement were present in the infected rats but not in the controls.
  • Increased levels of certain biomarkers in the infected rats indicated that oxidative stress responses from bacterial components likely contributed to the accelerated stroke onset.
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Objective: Sodium butyrate (butyric acid; BA) is a major metabolic by-product of the anaerobic periodontopathic bacteria present in subgingival plaque. We examined the effects of BA and/or indomethacin on cell proliferation, the expression of cyclooxygenases (COXs), prostaglandin (PG) receptors (EP1-4), extracellular matrix proteins, such as type I collagen and osteopontin, and PGE(2) production, using ROS17/2.8 cells as osteoblasts.

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Interleukin-17 (IL-17) is a cytokine secreted primarily by T(H)-17 cells that can stimulate the development of osteoclasts (osteoclastogenesis) in the presence of osteoblasts. IL-17, through osteoblasts, has indirect effects on the expression of bone resorption-related enzymes in osteoclasts, which have not been well clarified. Here, using MC3T3-E1 cells and RAW264.

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