Biomedical subjects

T Nikaido

Publications and source records attributed to T Nikaido.

221 records · Page 13Linked to original sources

PubMedDate not supplied

Combination therapy with podophyllin and vidarabine for human papillomavirus positive cervical intraepithelial neoplasia.

Our aim was to establish an effective non-surgical treatment for cervical intraepithelial neoplasia (CIN) through inactivation of human papillomavirus (HPV), the major etiological agent for this disease. We show that vidarabine, a DNA polymerase inhibitor, suppressed growth and HPV gene expression in human cervical keratinocytes immortalized by HPV or in cervical cancer cell lines. Expression of HPV-16 E6 and E7 proteins in normal cervical keratinocytes sensitized cells to apoptosis in the presence of podophyllin or vidarabine. We applied vidarabine ointment and/or podophyllin to cervical epithelium in 28 cases of CIN I-II to evaluate the therapeutic effectiveness of these agents. Co-application of vidarabine and podophyllin in six treatments caused regression of lesions cytologically and histologically, and disappearance of HPV-16 or -18 DNA in 17 of 21 (81%) women. Our results suggest that the combination of vidarabine and podophyllin therapy is an effective non-surgical treatment for HPV-positive CIN.

Adult↗

PubMedDate not supplied

In vitro surface analysis of active and arrested dentinal caries using a pH-imaging microscope.

This in vitro study evaluated the pH value of active and arrested caries lesions in deep dentinal caries using a pH-imaging microscope (SCHEM-100, HORIBA Ltd, Kyoto, Japan). Buccal-lingual cut sections of extracted human teeth that had either active or arrested dentinal caries lesions were placed on the pH-imaging sensor of the microscope. The pH values were compared statistically by one-way ANOVA and Fisher's PLSD test (p<0.05). In addition, both types of caries lesions were compared with a caries detector solution for this pH-imaging characterization. For both active and arrested lesions in dentin, the lowest pH values in the caries lesions (range from 5.3 to 6.6) were lower than that of intact dentin (range from 6.8 to 7.4). There were statistical differences between the lowest pH value within the active lesion (range from 5.3 to 5.8) and the arrested lesion (range from 6.3 to 6.6) (p<0.05). Although the arrested lesion was unstainable and impermeable to the dye, there was a close relationship between dye staining and pH-imaging characterization within the active lesion from visual inspection.

Adult↗

PubMedDate not supplied

Case report: breast hamartoma: MR findings.

We report a case of breast hamartoma which was diagnosed by magnetic resonance (MR) imaging and describe the MR features of this lesion. There was a perfect correlation between the findings at MR imaging and the macroscopic appearance of the tumor.

Adult↗

PubMedDate not supplied

Early bonding of resin cements to dentin--effect of bonding environment.

The aim of this study was to evaluate early tensile bond strengths of three commercial resin cements (a dual-cured and two chemically cured) to bovine dentin. Bonding was performed in two environmental conditions, namely room environment (23 degrees C/50% RH) and oral environment (30 degrees C/80% RH). Tensile bond strengths were recorded at 10 minutes, 1 hour, and 1 day after the bonding procedure was completed and were analyzed using one-way ANOVA, Fisher's PLSD test, and Student's t-test. The results showed that bond strengths were statistically greater for all materials (P < 0.05) over time, except for Bistite Resin Cement between 10 minutes and 1 hour (P > 0.05). Variation between the bonding environments was observed only for Bistite Resin Cement at both 10 minutes and 1 hour, and Panavia 21 at 10 minutes. It was concluded that bond strengths were initially weak for the chemically cured materials, and all materials showed significantly greater bond strengths over the first 24 hours, but bonding environment had little influence.

Analysis of Variance↗

PubMedDate not supplied

Bond strengths of resin to enamel and dentin treated with low-pressure air abrasion.

The effect of low-pressure (41.8 psi) air abrasion with alumina and glass beads on bonding to tooth substrates was evaluated. Tensile bond strengths of a bonding resin to air-abraded bovine enamel and dentin were measured. Scanning electron microscopy was used to observe (1) air-abraded surfaces, (2) fractured surfaces after the tensile bond test, and (3) interfaces of bonded specimens. Air abrasion with glass beads significantly decreased the bond strengths to enamel and dentin, whereas air abrasion with alumina decreased adhesion to enamel but not to dentin. The air-abraded enamel and dentin surfaces were irregularly roughened, and smear layers were created by air abrasion. Hybrid layers were observed at the interface between the bonding resin and the air-abraded dentin. The SEM photographs suggested that air abrasion may weaken the tooth surfaces, which could account for the decrease of the bond strengths.

Air Pressure↗