176 research outputs found
Serpentine Landslide Distribution Derived from Magnetic Measurement
Institute for Frontier Research on Earth Evolution(IFREE)Japan Marine Science and Technology Center(JAMSEC)Scedule:17-18 March 2003, Vemue: Kanazawa, Japan, Kanazawa Citymonde Hotel, Project Leader : Hayakawa, Kazuichi, Symposium Secretariat: XO kamata, Naoto, Edited by:Kamata, Naoto
Experiments on the Entrainment of Sediment by Turbidity Currents with the Use of Submarine Sediment
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
4.Rocks and minerals
Frontier Research Program for Subduction Dynamics, Japan Marine Science and Technology CenterFrontier Research Group for the Deep Sea Environment, Japan Marine Science and technology center東京大学Editor : Tazaki, Kazue, Cover:Scanning electoron microscopic photograph of Gallionella sp. in biomats of Aso caldera, Kyusyu, Japan. Various shapes of Gallonella sp. are shown (image:Moriichi, Shingo).COE, 金沢大学 水・土壌環境領域シンポジウム「地球環境における微生物の役割」, 日時:2002年12月4日(水)13:00~, 場所:金沢大学理学部3階第一実験
High Glucose Induces Severe Periodontitis.
Background/Aims: Diabetic patients are susceptible to severe periodontitis, but the precise mechanism is not fully understood. Aim of this study was to explore the biological pathogenesis of severe periodontitis in diabetic patients focusing on the crosstalk of human gingival fibroblasts (HGFs) and macrophages. Methods: A total of 70 periodontitis patients with or without diabetes mellitus (DM) were enrolled, and the statistical relationships of diabetic conditions to the periodontal inflammatory parameters were examined by cross-sectional study. In in vitro study, HGFs cell line CRL-2014® (ATCC) and differentiated THP-1 macrophages were cultured with normal glucose (NG: 5.5 mM) or high glucose (HG: 25 mM) condition, and treated with indicated inflammatory factors such as calprotectin (CPT), interleukin (IL)-1β and IL-6. To examine the effects of HG on soluble IL-6 receptor (sIL-6R) production in THP-1 macrophages, the supernatants were collected and the sIL-6R levels were measured by ELISA. To examine the effects of HG on IL-1β or IL-6-induced matrix metalloproteinase (MMPs) production in HGFs, the supernatants were collected. Levels of MMP-1 and tissue inhibitor of MMP-1 (TIMP-1) were measured by ELISA. Finally, after conditioned medium (CM) from THP-1 macrophages cultured with NG or HG conditions was collected, HGFs were treated with the CM. The supernatants were collected 24 hours later and the levels of MMP-1 and TIMP-1 were measured. To examine the specific effects of IL-1β contained in CM on MMP-1 and TIMP-1 production in HGFs, IL-1 receptor antagonist (IL-1ra) was used. Results: There were statistical correlation between IL-1β and sIL-6R levels in gingival crevicular fluid (GCF) and HbA1c in periodontitis patients with DM (IL-1β: P=0.035, sIL-6R: P=0.040). HG and CPT significantly induced sIL-6R production in THP-1 macrophages. HG significantly enhanced IL-1β or IL-6/sIL-6R-induced MMP-1 production in HGFs. The increase of MMP-1 by both IL-1β and IL-6/sIL-6R was significantly inhibited by specific ERK or IκB inhibitors. Corresponding to the regulation of MMP-1 production, HG condition increased the phosphorylation of p44/42 MAPK and IκBα in HGFs treated with IL-1β or IL-6/sIL-6R. Finally, MMP-1 production in HGFs cultured with HG increased significantly by CM from THP-1 macrophages cultured with HG. The induction of MMP-1 by the CM from THP-1 macrophages cultured with HG was significantly inhibited by dose dependent of IL-1ra in HGFs cultured with HG. Conclusion: Diabetic conditions such as HG induce IL-1β and sIL-6R production from macrophages in inflammatory periodontal tissues and may exacerbate the periodontitis synergistically via MMP-1 production from HGFs
Glycated Albumin in Gingival Crevicular Fluid from Patients With Diabetes
Background: Diabetes mellitus (DM) patients have a high prevalence of periodontitis. DM-associated periodontitis (DM-P) is characterized by severe inflammation and tissue destruction. To diagnose DM-P is important for cures of periodontitis and DM. The purpose of this study was to investigate the levels of glycated albumin (GA), a DM marker, and calprotectin, an inflammatory marker, in gingival crevicular fluid (GCF) from patients with periodontitis and DM.
Methods: Seventy-eight subjects participated in this study were the patients with DM, chronic periodontitis (CP), DM-P and healthy individuals (H). GCF and blood were collected from four groups. GA and calprotectin in GCF were analyzed using western blotting and ELISA, and their levels were compared among H, DM, CP, and DM-P groups. GA and glycated hemoglobin (HbA1c) in blood were determined, and the correlation between GCF GA level and blood HbA1c or GA level was investigated. ROC analysis for GCF GA level to predict DM was performed.
Results: GA was identified in GCF, and its amount and concentration in GCF samples from DM and DM-P were significantly higher than those of non-DM groups (H and CP). Calprotectin amount in GCF from CP and DM-P was significantly higher than that in H and DM groups. GCF GA level was positively correlated to blood HbA1c and GA level. ROC analysis of GCF GA level showed an optimal cut-off value to predict DM.
Conclusions: GA showed a high level in GCF from DM patients. GA and calprotectin in GCF may be useful markers to diagnose DM-associated periodontitis
Calprotectin/TLR4 induced induced-Cytokine Production
Calprotectin, a heterodimer of S100A8 and S100A9 molecules, is associated with inflammatory diseases such as inflammatory bowel disease. We have reported that calprotectin levels in gingival crevicular fluids of periodontitis patients are significantly higher than in healthy subjects. However, the functions of calprotectin in pathophysiology of periodontitis are still unknown. The aim of this study is to investigate the effects of calprotectin on the productivity of inflammatory cytokines in human gingival fibroblasts(HGFs). The HGFs cell line CRL-2014®(ATCC) were cultured, and total RNAs were collected to examine the expression of TLR2/4 and RAGE mRNA using RT-PCR. After the cells were treated with S100A8, S100A9 and calprotectin, supernatants were collected and the levels of IL-6 and MCP-1 were measured using ELISA methods. To examine the intracellular signals involved in calprotectin-induced cytokine production, several chemical inhibitors were used. Furthermore, after the siRNA-mediated TLR4 down-regulated cells were treated with S100A8, S100A9 and calprotectin, the levels of IL-6 and MCP-1 were also measured. HGFs showed greater expression of TLR4 mRNA, but notTLR2 and RAGE mRNA compared with human oral epithelial cells. Calprotectin increased significantly the production of MCP-1 and IL-6 in HGFs, and the cytokine productions were significantly suppressed in the cells treated with MAPKs, NF-kBand TLR4inhibitors. Furthermore, calprotectin-mediated MCP-1 and IL-6 production were significantly suppressed in TLR4down-regulated cells. Taken together, calprotectin inducesIL-6 and MCP-1 production in HGFs via TLR4 signaling that involves MAPK and NF-kB, resulting in the progression of periodontitis
β-Carotene Suppresses Cytokine Production
Periodontitis is associated with development of diabetes mellitus. Although lipopolysaccharide (LPS) of Porphyromonas gingivalis (Pg), a major pathogen of periodontitis, may lead the progression of diabetes complications, the precise mechanisms are unclear. We, therefore, investigated the effects of β-carotene on production of Pg LPS-induced inflammatory cytokines in human monocytes cultured high glucose (HG) condition. THP-1 cells were cultured under 5.5 mM or 25 mM glucose conditions, and cells were stimulated with Pg LPS. To investigate the productivity of TNF-α, IL-6 and MCP-1, cell supernatants were collected for ELISA. To examine the effects of NF-kB signals on cytokine production, Bay11-7082 was used. HG enhanced Pg LPS-induced production of TNF-α, IL-6 and MCP-1 via NF-kB signals in THP-1. β-carotene suppressed the enhancement of the Pg LPS-induced cytokine production in THP-1 via NF-κB inactivation. Our results suggest that β-carotene might be a potential anti-inflammatory nutrient for circulating Pg LPS-mediated cytokine production in diabetic patients with periodontitis
β-Carotene Suppresses Cytokine Production
Periodontitis is associated with development of diabetes mellitus. Although lipopolysaccharide (LPS) of Porphyromonas gingivalis (Pg), a major pathogen of periodontitis, may lead the progression of diabetes complications, the precise mechanisms are unclear. We, therefore, investigated the effects of β-carotene on production of Pg LPS-induced inflammatory cytokines in human monocytes cultured high glucose (HG) condition. THP-1 cells were cultured under 5.5 mM or 25 mM glucose conditions, and cells were stimulated with Pg LPS. To investigate the productivity of TNF-α, IL-6 and MCP-1, cell supernatants were collected for ELISA. To examine the effects of NF-kB signals on cytokine production, Bay11-7082 was used. HG enhanced Pg LPS-induced production of TNF-α, IL-6 and MCP-1 via NF-kB signals in THP-1. β-carotene suppressed the enhancement of the Pg LPS-induced cytokine production in THP-1 via NF-κB inactivation. Our results suggest that β-carotene might be a potential anti-inflammatory nutrient for circulating Pg LPS-mediated cytokine production in diabetic patients with periodontitis
AGEs increase IL-6 and ICAM-1 expression
Background and Objectives: Diabetes mellitus (DM) is a risk factor for periodontal diseases and may exacerbate the progression of the pathogenesis of periodontitis. Advanced glycation end-products (AGEs) cause DM complications relative to levels of glycemic control and larger amounts accumulate in the periodontal tissues of patients with periodontitis and DM. In the present study, we investigated the effects of AGEs on the expression of inflammation-related factors in human gingival fibroblasts (HGFs) in order to elucidate the impact of AGEs on DM-associated periodontitis.
Materials and Methods: HGFs were cultured with or without AGEs. Cell viability was examined, and RNA and protein fractions were isolated from AGE-treated cells. The expression of IL-6, ICAM-1, and the receptor for AGE (RAGE) was investigated using RT-PCR, quantitative real-time PCR, and ELISA, and reactive oxygen species (ROS) activity was measured using a kit with 2’,7’-dichlorofluorescin diacetate. Human monocytic cells (THP-1) labelled with a fluorescent reagent were co-cultured with HGFs treated with AGEs and IL-6 siRNA, and the adhesive activity of THP-1 cells to HGFs was assessed. The expression of IL-6 and ICAM-1 was examined when HGFs were pretreated with recombinant human IL-6 (rhIL-6), the siRNAs of RAGE and IL-6, and inhibitors of MAPK and NF-κB, and then cultured with and without AGEs. The phosphorylation of MAPK and NF-κB was assessed using Western blotting.
Results: AGEs increased the mRNA and protein expressions of RAGE, IL-6, ICAM-1 and ROS activity in HGFs, and promoted the adhesion of THP-1 cells to HGFs, but had no effect on cell viability until 72 h. rhIL-6 increased ICAM-1 expression in HGFs, while the siRNAs of RAGE and IL-6 inhibited AGE-induced IL6 and ICAM1 mRNA expression, and IL-6 siRNA depressed AGE-induced THP-1 cell adhesion. AGEs increased the phosphorylation of p38 and ERK MAPKs, p65 NF-κB, and IκBα, while inhibitors of p38, ERK MAPKs, and NF-κB significantly decreased AGE-induced IL-6 and ICAM-1 expression.
Conclusions: AGEs increase IL-6 and ICAM-1 expression via the RAGE, MAPK and NF-κB pathways in HGFs and may exacerbate the progression of the pathogenesis of periodontal diseases
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