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Shuichi Ito

Publications and source records attributed to Shuichi Ito.

28 records · Page 2Linked to original sources
PubMed2005

Effects of multiple coatings of two all-in-one adhesives on dentin bonding.

PURPOSE: Simple changes to bonding technique can improve resin-dentin bond strengths. The objective of this study was to evaluate the effects of multiple coatings of two all-in-one adhesive resins on both microtensile bond strength (microTBS) and nanoleakage. MATERIALS AND METHODS: The mid-coronal occlusal dentin of extracted human molars was used. Two all-in-one adhesives--iBond (Heraeus Kulzer) and Xeno III (Caulk Dentsply)--were applied to 320-grit abraded dentin surfaces. In groups 1 and 3 during bonding, monomer application and solvent evaporation were done 1, 2, 3, 4 or 5 times on the dentin surface before light curing. In groups 2 and 4 after light curing the first layer, the adhesive was re-applied, the solvent evaporated, and the layer light cured. This was repeated from 2 to 5 times, followed by creation of composite buildups. After 24 h storage in 37 degrees C water, the teeth were sectioned perpendicular to the adhesive interface to produce multiple beams of composite-bonded dentin, approximately 0.9 mm2 in area. These were tested to failure in tension. Data were evaluated by three-way ANOVA (material vs coatings vs light curing) followed by multiple comparisons at alpha = 0.05. Additionally, nanoleakage of silver uptake and adhesive layer thickness were evaluated using transmission electron microscopy (TEM). RESULTS: The results indicated that bond strengths increased with the number of coatings (p < 0.0001) with both adhesives, up to 3 layers, especially if each layer was light cured. Nanoleakage of silver tended to decrease with each coat in both adhesive systems. CONCLUSION: By simply applying more coats of adhesive, the strength and quality of dentin adhesion can be improved.

Composite Resins↗
PubMed2004

In vitro apatite induction by osteopontin: interfacial energy for hydroxyapatite nucleation on osteopontin.

Noncollagenous phosphoproteins that interact with type I collagen are thought to nucleate the mineral phase to the collagen fibril network of mineralized tissues. We previously reported that a specific dentin phosphoprotein, phosphophoryn, crosslinked to an insoluble substrate such as type I collagen fibrils, was an effective nucleator of apatite. In this study, we investigated the capacity of another phosphoprotein in dentin, osteopontin, for apatite nucleation in vitro. Osteopontin purified from bovine milk was either absorbed to agarose beads or crosslinked to agarose beads. Each preparation was incubated at 37 degrees C in metastable solutions. Apatite was induced by osteopontin that was crosslinked to agarose beads, whereas osteopontin adsorbed to agarose beads failed to induce apatite crystal formation. Using classical nucleation theory, the interfacial energy for hydroxyapatite nucleation on osteopontin crosslinked to agarose beads was determined to be 94.7 ergs/cm(2). This value is larger than that for phosphophoryn, though it is similar to that for hydroxyapatite. The present study indicates that osteopontin, like phosphophoryn, has a high potential to induce apatite formation when it is covalently bound to some substrate in vitro, and suggests the possibility that osteopontin bound to type I collagen may induce apatite formation in vivo.

Animals↗
PubMed2004

Hemolytic uremic syndrome induced by lipopolysaccharide and Shiga-like toxin.

Induction of experimental hemolytic uremic syndrome (HUS) by simply administering Shiga-like toxin (Stx) to rodents has not yet been successful. Attention has been paid to the role of lipopolysaccharide (LPS) in the pathogenesis of HUS. In this study, we showed successful induction of an experimental HUS in LPS responder mice by administering Stx together with LPS. Intraperitoneal administration of 200 ng of Stx 2 for 2 days, followed by 250 microg of LPS on the 2nd day of Stx administration, caused a significant decrease of thrombocytes and deterioration of renal function, with proteinuria and hematuria. Electron microscopy revealed alterations of glomerular endothelial cells. Administration of Stx alone or LPS alone caused neither hematological nor histopathological changes, as were observed with Stx and LPS co-administration. Interestingly, when LPS was administered before Stx, no hematological and histological changes were observed. The results showed that LPS was essential for the induction of HUS, but LPS pretreatment might protect against Stx toxicity. The order of LPS and Stx administration is important for the induction of experimental HUS.

Animals↗
PubMed2004

Efficacy of plasma exchange therapy for Kawasaki disease intractable to intravenous gamma-globulin.

Kawasaki disease (KD) causes coronary artery lesions (CALs) in 500 Japanese children each year. Intravenous gamma-globulin (IVGG) decreases the incidence of these lesions from 25% to 8% of the total KD cases. We examined whether plasma exchange is a safe and effective prophylaxis against CALs in children with KD intractable to IVGG therapy. Eighty-nine children with KD at high risk of CALs were selected on the basis of increases in fractional changes in inflammatory markers such as white blood cell count, neutrophil count, and C-reactive protein between the baseline and 1-2 days after IVGG treatment. Of 105 children who received a second course of IVGG therapy because the initial course was ineffective, plasma exchange (PE) was performed in 46 children who had not responded to the second IVGG treatment. The outcome was compared with the results when a third course of IVGG therapy was given to the other 59 children. No complications occurred with the plasma exchange therapy. CALs developed in only 8 of the 46 children (17.3%) who underwent plasma exchange, but they occurred in 24 of the 59 (40.7%) who had received a third course of IVGG therapy (P << 0.0012). We concluded that PE was a safe, effective prophylactic measure against CALs in children with KD intractable to IVGG therapy. PE should be performed at an early stage, as soon as fractional increases in inflammatory markers are found after IVGG therapy.

Journal Article↗
PubMed2004

HLA-DRB1*15021 is the predominant allele in Japanese patients with juvenile dermatomyositis.

OBJECTIVE: To investigate HLA molecules and genes in Japanese patients with juvenile dermatomyositis (JDM). METHODS: Twelve patients (8 girls and 4 boys) with ages of onset between 3 and 15 years were included. HLA class I antigen phenotypes were serologically typed by the Terasaki-NIH standard method. DNA was extracted from peripheral blood leukocytes using the phenol-chloroform extraction procedure, and stored at -70 degrees C until use. Genomic DNA for HLA-DRB1, HLA-DQA1, and HLA-DQB1 alleles in JDM patients and controls was determined by the direct sequence method. RESULTS: HLA-A24 and B52 were each detected in 7 cases (OR = 0.86, 5.02, p = 0.930, 0.006, respectively). HLA-DRB1*15021 was observed in 7 patients. This was significantly more frequent than occurred in the controls (OR = 5.72, p = 0.002). Seven patients out of 12 (58%) had the combination HLA-B52, DRB1*15021, DQA1*0103, and DQB1*0601. CONCLUSION: Our results suggest that the susceptibility gene for JDM either is HLA-DRB1*15021 or is present near the HLA-DRB1 locus. This differs from previous reports that describe the association with HLA-DQA1*0501 in Caucasian patients with JDM. The combination HLA-B52, DRB1*15021, DQA1*0103, and DQB1*0601 may contribute to the pathogenesis of JDM in Japanese patients.

Adolescent↗
PubMed2003

[Effects of therapies on childhood systemic lupus erythematosus].

We analyzed the effects of three therapies on 30 patients with childhood systemic lupus erythematosus, and classified the patients into three groups. The therapies were as follows; Group A (8 cases), methylpredni-solone (mPSL) pulses plus oral prednisolone (PSL) alone, Group B (10 cases), mPSL pulses plus oral PSL and mizoribine (MZB) or azathioprine (AZP), Group C (12 cases), mPSL pulses and intravenous cyclophosphamide (IVCY) pulse therapy plus oral PSL and MZB or AZP. Three years after treatment, we compared the laboratory data (C3, C4, CH50 and anti-DNA antibody), the SLEDAI scores and numbers of relapses in these three groups. We demonstrated that group C had the best data, and this data indicated that the median C3, C4 and CH50 increased and that the median anti-DNA antibody and the mean of the numbers of relapses decreased. In conclusion, the combination of immunosuppressants and IVCY appeared to offer great benefits in childhood systemic lupus erythematosus.

Administration, Oral↗
PubMedDate not supplied

In vitro study of remineralization of dentin: effects of ions on mineral induction by decalcified dentin matrix.

We examined the effects of various ions on the mineralization of dentin matrix in vitro. Demineralized dentin matrix was incubated in a metastable calcium phosphate solution with or without silicate, fluoride, calcium, phosphate, magnesium or silver. Insoluble dentin matrix induced mineral formation after incubation for 10.2 h in the metastable solution without added ions. Silicate at 5 microM and fluoride at 40 microM significantly reduced the mineral induction time. At least 200 microM calcium or 100 microM phosphate was required to promote mineral induction. Conversely, magnesium and silver concentrations as low as 10 and 2 microM inhibited mineral induction. The mineral induced by each sample after incubation for 24 h was identified by its X-ray diffraction pattern as apatite. We concluded that silicate is a stronger inducer of remineralization of dentin matrix than fluoride, calcium or phosphate, and that magnesium and silver inhibit the induction of remineralization of dentin matrix.

Animals↗
PubMedDate not supplied

The microtensile bond strength of self-etching adhesives to ground enamel.

It is uncertain whether single-phase self-etching adhesives form bonds to enamel as reliable as those of etch-and-rinse adhesives. This study compared the microtensile bond strengths to ground enamel of three self-etching adhesive systems, a self-etching primer system and an etchand-rinse adhesive system. Human enamel was ground flat with 320-grit silicone carbide paper. The self-etching adhesives iBond (Heraeus Kulzer), Prompt L-Pop (3M ESPE) and Xeno III (Caulk/Dentsply), the adhesive with a self-etching primer Clearfil SE Bond (Kuraray) and the etch-and-rinse adhesive Scotchbond Multipur-pose (3M/ESPE) were applied as directed, followed by a core of the same manufacturers' hybrid resin composite. A microtensile bond strength evaluation was performed after 48 hours of water storage, using untrimmed beams approximately 0.9 mm2 in cross-sectional area at a crosshead speed of 0.6 mm/minute. There were no pretest failures in any group, and failures were predominately adhesive or mixed. Adhesion to enamel of Clearfil SE was not significantly different from Scotchbond Multi-Purpose, while the three self-etching adhesive systems demonstrated significantly lower bond strengths (One-way ANOVA, Tukey-Kramer Multiple-Comparison Test, p < 0.00001).

Acid Etching, Dental↗
PubMedDate not supplied

Microtensile dentin bond strength of self-etching resins: effect of a hydrophobic layer.

In this study, the microtensile bond strength of resin composites to dentin was determined when hydrophilic self-etching resins were used with and without an additional layer of a more hydrophobic adhesive. Included were three single-step self-etching adhesives, Adper Prompt L-Pop (3M ESPE), iBond GI (Heraeus Kulzer, Inc) and Xeno III (Caulk/Dentsply), and as a negative control, UniFil Bond (GC America), a self-etching primer with a separate adhesive. Each product was evaluated using a hybrid resin composite from its respective manufacturer, and each was used as directed and then used with an added layer of a more hydrophobic resin from its respective manufacturer. Testing was performed after 72 hours using a "non-trimming" microtensile test at a crosshead speed of 0.6 mm/minute. When the products were used according to manufacturers' directions, iBond had a significantly higher bond strength to dentin than the other three products (p<0.001), which were not significantly different from each other. For the three self-etching adhesive systems, the addition of a layer of a more hydrophobic resin produced significantly higher bond strengths to dentin (p<0.001), while no significant effect was found for the self-etching primer (p=0.40). A significant interaction was found between the variables product and adhesive treatment. The TEM evaluation of Prompt L-Pop and iBond demonstrated reduced nanoleakage with the additional resin layer.

Composite Resins↗