Mechanisms involved in suppression of ADAMTS4 expression in synoviocytes by high molecular weight hyaluronic acid.

Aggrecan degradation is considered to play a key role in the progression of osteoarthritis (OA). Aggrecanases are members of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) family, and degrade aggrecan in OA cartilage. The aim of this study was to clarify the mechanisms of expression of ADAMTS4 induced by IL-1β in human fibroblast-like synoviocyte (HFLS) cells by high molecular weight hyaluronan (HMW-HA), a therapeutic agent used for OA.

Expression of MCP-1 and fractalkine on endothelial cells and astrocytes may contribute to the invasion and migration of brain macrophages in ischemic rat brain lesions.

Some macrophages expressing NG2 chondroitin sulfate proteoglycan (NG2) and the macrophage marker Iba1 accumulate in the ischemic core of a rat brain subjected to transient middle cerebral artery occlusion (MCAO) for 90 min. These cells are termed BINCs (for brain Iba1(+) /NG2(+) cells) and may play a neuroprotective role. Because BINCs are bone marrow-derived cells, they are able to invade ischemic tissue after the onset of an ischemic insult.

A. actinomycetemcomitans LPS enhances foam cell formation induced by LDL.

The objective of this study was to examine whether native low-density lipoprotein (LDL) induces foam cell formation by macrophages and to examine the effect of lipopolysaccharide (LPS) on native LDL-induced foam cell formation by macrophages in vitro. RAW 264.7 cells were cultured with LDL or high-density lipoprotein (HDL) in the presence of LPS derived from Aggregatibacter actinomycetemcomitans.

Essential role of JAK/STAT pathway in the induction of cell cycle arrest in macrophages infected with periodontopathic bacterium Aggregatibacter actinomycetemcomitans.

In the present study, phosphorylation of signal transducers and activators of transcription 3 (STAT3) was found to be important in the induction of G1 cell cycle arrest in murine macrophages infected with Aggregatibacter actinomycetemcomitans. First, we focused on suppressor of cytokine signaling 3 (SOCS3) as a negative regulator of the JAK/STAT pathway. Flow cytometric analysis showed that A.

Oral cancer diagnosis via a ferrocenylnaphthalene diimide-based electrochemical telomerase assay.

Background: Telomerase is regarded as a good marker for cancer because it is unregulated in most tumor cells compared with normal cells. We evaluated telomerase activity in the lysate of tumor tissue and surrounding cells of oral cancer patients by an electrochemical technique, dubbed the electrochemical telomerase assay (ECTA).

Methods: The assay used ferrocenylnaphthalene diimide (FND) as the probe.

Excited States in Cycloparaphenylenes: Dependence of Optical Properties on Ring Length.

Hoop-shaped conjugated molecules, cycloparaphenylenes (CPPs), are simple strings of benzene rings with para linkages that have an ideal quasi-one-dimensional structure without edges. Here, we report optical properties of [n]CPPs (n = 9, 12, 14, 15, 16) clarified by one- and two-photon excitation spectroscopy. We showed that in this system the lowest unoccupied molecular orbital (LUMO) state has the same symmetry as the highest occupied molecular orbital (HOMO) state, and determined the transition energy of the optically forbidden HOMO-LUMO gap.

Quantitative discrimination of Aggregatibacter actinomycetemcomitans highly leukotoxic JP2 clone from non-JP2 clones in diagnosis of aggressive periodontitis.

Background: Aggregatibacter actinomycetemcomitans is the etiological agent of periodontitis, and there is a strong association between clone JP2 and aggressive periodontitis in adolescents of African descent. The JP2 clone has an approximately 530-bp deletion (∆530) in the promoter region of the lkt/ltx gene, which encodes leukotoxin, and this clone has high leukotoxic activity. Therefore, this clone is very important in aggressive periodontitis.

A case of osteogenesis imperfecta type II caused by a novel COL1A2 gene mutation: endoscopic third ventriculostomy to prevent hydrocephalus.

Osteogenesis imperfecta (OI) is a hereditary connective tissue disorder caused by defects in type I collagen synthesis. OI is generally classified into four types (I to IV), and the clinical prognosis varies from a lethal outcome for type II and varying deformities for type III to a normal lifespan for the other types. We describe a female patient with biochemically confirmed OI caused by a novel mutation in the COL1A2 gene.

Promoting effects of thymosin β4 on granulation tissue and new bone formation after tooth extraction in rats.

Objectives: The aim of this study was to evaluate the effects of thymosin β4 (TB4) on wound healing after tooth extraction in rats.

Study Design: After extraction of the rats' mandibular first molar teeth, a synthetic partial peptide of TB4 was injected intraperitoneally at the time of extraction and every day thereafter for 6 days. Control subjects for the treatment received identical amounts of phosphate-buffered saline solution in the same manner.

Factors associated with dry mouth in dependent Japanese elderly.

Objectives: To identify factors associated with dry mouth.

Background: Dry mouth adversely affects oropharyngeal health, particularly in elderly, and can lead to pneumonia. A better understanding of the epidemiology of dry mouth is therefore important in improving treatment strategies and oral health in high-risk elderly patients.

Possible Involvement of Smad Signaling Pathways in Induction of Odontoblastic Properties in KN-3 Cells by Bone Morphogenetic Protein-2: A Growth Factor to Induce Dentin Regeneration.

We examined the effects of bone morphogenetic protein-2 (BMP-2) on growth, differentiation, and intracellular signaling pathways of odontoblast-like cells, KN-3 cells, to clarify molecular mechanisms of odontoblast differentiation during pulp regeneration process. After treatment with BMP-2, the cell morphology, growth, alkaline phosphatase (ALP) activity, and the activation and expression of BMP-induced intracellular signaling molecules, such as Smad1/5/8 and Smad6/7, as well as activities of dentin sialoprotein (DSP) and dentin matrix protein 1 (DMP1), were examined. BMP-2 had no effects on the morphology, growth, or ALP activity of KN-3 cells, whereas it induced the phosphorylation of Smad1/5/8 and expression of Smad6/7.

Mechanisms involved in inhibition of chondrogenesis by activin-A.

Objectives: Activin-A, a member of the TGF-β family, is known to be present in bone and cartilage. Although, involvement of the TGF-β family in chondrogenesis has been reported, the mechanism by which activin-A regulates chondrogenesis has not been fully elucidated. The aim of this study was to investigate the effects of activin-A on chondrocyte differentiation in vitro.

Dual effects of heparin on BMP-2-induced osteogenic activity in MC3T3-E1 cells.

Heparin displays several types of biological activities by binding to various extracellular molecules, including pivotal roles in bone metabolism. We have previously reported that heparin competitively inhibits the binding activity of bone morphogenic protein-2 (BMP-2) to BMP and the BMP receptor (BMPR) and suppresses BMP-2 osteogenic activity. In the present study, we examined whether heparin affects osteoblast differentiation induced by BMP-2 at various time points in vitro.

Local regeneration of dentin-pulp complex using controlled release of fgf-2 and naturally derived sponge-like scaffolds.

Restorative and endodontic procedures have been recently developed in an attempt to preserve the vitality of dental pulp after exposure to external stimuli, such as caries infection or traumatic injury. When damage to dental pulp is reversible, pulp wound healing can proceed, whereas irreversible damage induces pathological changes in dental pulp, eventually requiring its removal. Nonvital teeth lose their defensive abilities and become severely damaged, resulting in extraction.

Inositol phosphate kinase Vip1p interacts with histone chaperone Asf1p in Saccharomyces cerevisiae.

Histone eviction and deposition are critical steps in many nuclear processes. The histone H3/H4 chaperone Asf1p is highly conserved and is involved in DNA replication, DNA repair, and transcription. To identify the factors concerned with anti-silencing function 1 (ASF1), we purified Asf1p-associated factors from the yeast Saccharomyces cerevisiae by a GST pull-down experiment, and mass spectrometry analysis was performed.

Streptococcus sanguinis induces foam cell formation and cell death of macrophages in association with production of reactive oxygen species.

Streptococcus sanguinis, a normal inhabitant of the human oral cavity, is a common streptococcal species implicated in infective endocarditis. Herein, we investigated the effects of infection with S. sanguinis on foam cell formation and cell death of macrophages.

Enumeration of viable Enterococcus faecalis, a predominant apical periodontitis pathogen, using propidium monoazide and quantitative real-time polymerase chain reaction.

To discriminate between viable and non-viable Enterococcus faecalis, the predominant pathogen in apical periodontitis, a real-time PCR method combined with propidium monoazide (PMA) was developed and evaluated. PMA had no antimicrobial effect on E. faecalis cells and permitted enumeration of both viable and non-viable cells.

Bactericidal Effects of Diode Laser Irradiation on Enterococcus faecalis Using Periapical Lesion Defect Model.

Objective. Photodynamic therapy has been expanded for use in endodontic treatment. The aim of this study was to investigate the antimicrobial effects of diode laser irradiation on endodontic pathogens in periapical lesions using an in vitro apical lesion model.

Correlations between health status and OralChroma™-determined volatile sulfide levels in mouth air of the elderly.

Dimethyl sulfide (DMS), a volatile sulfur compound (VSC) found in mouth air, is thought to be associated with systemic diseases; this in contrast to the two other VSCs found in mouth air: hydrogen sulfide and methyl mercaptan (MM). This study aimed to validate the relationship between DMS in mouth air and oral and systemic factors. The subjects were 393 elderly Japanese volunteers participating in an oral and systemic health survey.

Inhibition of adjuvant arthritis in rats by electroporation with interleukin-1 receptor antagonist.

To assess the protective effects of the cytokine inhibitor interleukin-1 receptor antagonist (IL-1ra) on gene induction, an electroporation technique to treat adjuvant-induced arthritis (AIA) in rats was established, and its advantage was estimated in the present study. Electroporation with human IL-1ra was performed in Lewis rats before and after induction of AIA. Local inflammation was evaluated by monitoring hind paw swelling, whereas histological evaluations were performed using paraffin embedded sections of hind paw specimens stained with hematoxylin and eosin.

Screening for estrogenic and antiestrogenic activities of plants growing in Egypt and Thailand.

Background: There is a growing demand for the discovery of new phytoestrogens to be used as a safe and effective hormonal replacement therapy.

Materials And Methods: The methanol extracts of 40 plants from the Egyptian and Thailand folk medicines were screened for their estrogen agonist and antagonist activities. The estrogenic and antiestrogenic effects of the tested extracts were carried out using the yeast two-hybrid assay system expressing ERα and ERβ.

Effects of heat stress and starvation on clonal odontoblast-like cells.

Introduction: Heat stress during restorative procedures, particularly under severe starvation conditions, can trigger damage to dental pulp. In the present study, we examined effects of heat stress on odontoblastic activity and inflammatory responses in an odontoblast-like cell line (KN-3) under serum-starved conditions.

Methods: Viability, nuclear structures, and inflammatory responses of KN-3 cells were examined in culture medium containing 10% or 1% serum after exposure to heat stress at 43°C for 45 minutes.

Apoptosis and survivability of human dental pulp cells under exposure to Bis-GMA.

Objective: In the present study, we examined whether 2, 2-bis [4-(2-hydroxy-3-methacryloxypropoxy) phenyl] propane (Bis-GMA) has effects on LSC2 cells, human dental pulp cell line.

Material And Methods: The viability, cell cycle, and morphology of LSC2 cells were analyzed after exposure to several different concentrations of Bis-GMA. The recovery of viability of Bis-GMA exposed cells was also analyzed in the condition without Bis-GMA.

Role of heme oxygenase-1 in inflammatory response induced by mechanical stretch in synovial cells.

Objective: The purpose of this study was to investigate the mechanism by which heme oxygenase-1 (HO-1) regulates inflammatory responses induced by mechanical stretch in human fibroblast-like synoviocyte (HFLS) cells.

Materials And Methods: HFLS cells were cultured in the presence of hemin and seeded into fibronectin-coated silicon chambers. The chambers were attached to a stretching apparatus which applied a uniaxial sinusoidal stretching force.