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Get PDFIn prosthodontic treatment, reconstruction of a proper occlusal contact relationship is very important as well as reconstruction of a proper interproximal relationship and marginal fitness. Unfortunately, occlusal relationships are sometimes lost in the process of occlusal adjustment of crowns. The purpose of this study was to compare the occlusal contacts of single crown fabricated by two different types of impression techniques. Nine subjects, whose molars required treatment with crown restoration, were enrolled in this study. Full cast crowns were fabricated using two types of impression techniques: the conventional impression method (CIM) and the bite impression method (BIM). The occlusal contacts of crowns were precisely evaluated at the following stages: after occlusal adjustment on the articulator (Step 0), before occlusal adjustment in the mouth (Step 1), after occlusal adjustment at the intercuspal position (Step 2), and after occlusal adjustment during lateral and protrusive excursions (Step 3). The number of occlusal contacts of the crowns on the functional cusps fabricated with BIM was significantly greater than that with CIM after occlusal adjustment. For this reason, the crowns fabricated with BIM might have a more functionally desirable occlusal surface compared to the crowns fabricated with CIM.departmental bulletin pape
Get PDFVarious gelatinizers, which facilitate oral ingestion, are employed in patients with dysphagia. The purpose of this study was to histologically clarify the influence of various gelatinizers on the lung, using rats.We administered 0.2 ml/kg of 0.1% xanthangam, a 0.25% commercially available xanthangam gelatinizer, 0.35% ι-carrageenan, 0.5% κ-carrageenan, 1% gelatin, 0.15% agar, physiological saline, tap water, and isopropanolpurified 0.1% anthangam/0.35% ι-carrageenan into the trachea of 8- to 9-week-old male SD rats. The lungs were extirpated after 24 and 72 hours. Neutrophil infiltration in the alveolar space was expressed as the mean number of neutrophils in 30 randomly selected high-power fields. In the xanthangam (451.0 ±204.0 cells)-, and the ι-carrageenan (424.4 ±257.2) treated groups, the neutrophil counts after 24 hours was significantly greater than in the physiological saline (33.0 ± 22.6) - treated group (p<0.05). In the available xanthangam gelatinizer (290.0 ±86.8) -treated group was no significant difference in the physiological saline - treated group . In the isopropanol - purified xanthangam ( 90.2 ± 42.3)-treated group, the neutrophil counts after 24 hours were significantly smaller than in the nonpurified xanthangam -treated group.These results suggest that lung tissue inflammatory responseinducing features depend on the type of gelatinizer. On the other hand, purification reduces the lung-damaging features of xanthangam.departmental bulletin pape
Get PDFBackground: To identify the clinical T stage by endoscopy is a major diagnostic goal for superficial esophageal squamous cell carcinoma (ESCC). The completion of a microvascular morphological study of mucosal lesions is necessary to optimize therapy. Materials and methods: Images of 197 intra-papillary capillary loops (IPCLs) captured by magnified endoscopy from 15 esophagectomy specimens were studied for their morphological features and IPCL dimensions. Results: The microvascular morphology was classified into four basic major patterns: 1. spiral loop, 2. wide loop (WL), 3. globular (G) and 4. reticular pattern. The microvascular features and dimensions differed according to the depth of tumor invasion. Especially the mean bundle outline (IPCL diameter) showed significant changes as 20.02, 22.32, and 27.08 μm, respectively, for M1, M2 and M3, respectively (M1:M2 P < 0.05, M2:M3 P < 0.01). Conclusions: During tumor stage progression, a high-volume blood demand and cancer cell overgrowth to occupy the laminar propria mucosa (LPM) cause obvious elongation, thickening, branching, irregularity and deformity of the IPCL, which were characteristics of M3 lesions. The results of the present study support and can be applied with the current Japanese classification for improving the diagnostic accuracy, especially to differentiate between M2 and M3 lesions based on the endoscopic findings.departmental bulletin pape
Get PDFBackground-Although attritive and abrasive wear of recent composite resins has been substantially reduced, in vitro wear testing with reasonably simulating devices and quantitative determination of resulting wear is still needed. Three-dimensional scanning methods are frequently used for this purpose. The aim of this trial was to compare maximum depth of wear and volume loss of composite samples, evaluated with a contact profilometer and a non-contact CCD camera imaging system, respectively. Method-Twenty-three random composite specimens with wear traces produced in a ball-on-disc sliding device, using poppy seed slurry and PMMA suspension as third-body media, were evaluated with the contact profilometer (TalyScan 150, Taylor Hobson LTD, Leicester, UK) and with the digital CCD microscope (VHX1000, KEYENCE, Osaka, Japan). The target parameters were maximum depth of the wear and volume loss. Results — The individual time of measurement needed with the non-contact CCD method was almost three hours less than that with the contact method. Both, maximum depth of wear and volume loss data, recorded with the two methods were linearly correlated (r 2> 0.97; p< 0.01). Conclusion — The contact scanning method and the non-contact CCD method are equally suitable for determination of maximum depth of wear and volume loss of abraded composite resins.departmental bulletin pape
Get PDFBackground We have previously reported that human umbilical cord blood (UCB)-nucleated cells differentiate into hepatocyte-like cells when cultured in a 5-cytokine cocktail medium. We further found that UCB cells rather differentiated into dendritic-shaped cells by coculture with a human stellate cell (HSC) line, LI90. Methods Monocytes from UCB and adult peripheral blood were cocultured with LI90 or rat primary HSCs in a cell-culture insert. Monocytes were also cultured with LI90-conditioned medium containing secreted factors, which were analyzed by a cytokine array. Results In the coculture with LI90, resulting dendritic-shaped cells from monocytes expressed dendritic cell (DC) markers and activated allogeneic T cells, indicating that the dendritic-shaped cells were DCs. LI90 in the cytokine cocktail medium secreted various inflammatory factors, such as granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4. Fibroblast growth factor-2 in the cytokine cocktail was responsible for GM-CSF production from LI90 cells and for differentiation of monocytes into DCs in the LI90 coculture. Moreover, the coculture of monocytes with activated HSCs derived from damaged rat liver induced the differentiation of DCs, whereas quiescent HSCs derived from normal liver scarcely induced such a change. Conclusion These results suggest that activated HSCs are involved in differentiation of monocytes into DCs in the liver.departmental bulletin pape
Get PDFPrevious research has shown that mastication reduces shifts in the center of gravity of persons standing still. The present research was conducted to determine whether mastication improves reactive balance in the standing position in response to unanticipated external disturbances. The subjects were 32 healthy male adults (mean age 21.1 years, standard deviation (SD) 0.7 years). Latency data determined with the Motor Control Test of Computerized Dynamic Posturography (CDP) were compared for the three conditions of mastication status, the direction of translation, and the magnitude of translation, using three-way repeated measures ANOVA and lower-order ANOVA with the three conditions separated. Latency was significantly shorter with mastication than with the lower jaw relaxed (P < 0.00001). Mastication alone, however, cannot be considered significant because of the complex interactions involved among the three conditions. Mastication increases not only static balance but also reactive balance in response to unanticipated external disturbances. Gum chewing may therefore reduce falls among elderly persons with impaired balance.departmental bulletin pape
Get PDFSilica coating modifies hydrophobic denture base materials to have a hydrophilic surface. The purpose of this study was to evaluate the effect of silica coating to a denture base material on resistance to Candida albicans ( C. albicans ) adherence. Specimens were prepared by polymerizing an acrylic denture lining material and polished using silicon carbide paper up an abrasive grade of 1000. The specimens of a coated group were treated three times by a silica coating agent using a nonwoven cloth. The surface properties were evaluated by contact angle measurement, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). A C. albicans adherence assay was performed after 1.5, 6, and 24 h incubation. The mean contact angle of the coated group showed significantly lower than that of the non-coated group (p < 0.05). In the coated group, the surface roughness decreased in SEM images, and Si was continuously detected in EDS analysis. At 24 h incubation time, the colony forming unit of C. albicans on the coated group was significantly reduced compared to the non-coated group (p < 0.05). These results suggest that hydrophilic surface modification by the silica coating reduces C. albicans adherence and could contribute to daily denture care.departmental bulletin pape
Get PDFL-Arginine is the common substrate for arginase and nitric oxide synthase (NOS). Arginase converts L-arginine to urea and L-ornithine. L-Ornithine is the principal precursor for the production of polyamines and L-proline, which are required for cell proliferation and collagen synthesis. Endothelial NOS is expressed in the human endometrial glandular epithelium, but the expression and physiological roles of arginase in the human endometrium are not clear. The objective of this study was to investigate the expression and distribution patterns of arginases I (A-I) and II (A-II) in the human endometrium by using immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR), and western blotting. A-I and A-II were detected by immunohistochemistry in human endometrial epithelial cells during the proliferative and secretory phases of the menstrual cycle. RT-PCR showed that A-I and A-II mRNA were expressed in human endometrial tissue. Western blotting analysis results showed the expression of A-II protein. Immunohistochemistry and western blotting results showed that expression levels of A-II were significantly higher in the secretory phase than in the proliferative phase. Increased A-II levels in the secretory phase may be responsible for endometrial growth by increasing polyamines and proline products.departmental bulletin pape
Get PDFHistologic evaluation of low-grade or high-grade intraepithelial neoplasia (LG-IN or HG-IN) of the esophagus is important for estimating the risk of progression to invasive carcinoma. Discrimination between LG-IN and HG-IN, or neoplasia and non-neoplastic lesion (NNL), however, is occasionally difficult. This study was designed to evaluate whether cytokeratin expression can be used for discrimination of these lesions. Esophageal Iodine-unstained lesions (n=154), less than 10 mm, were classified into HG-IN, LG-IN, and NNL. These lesions together with 154 foci of normal esophageal epithelium (NEE) were examined by immunohistochemistry for cytokeratins (CK4 and CK13), p53 overexpression, and the MIB-1 labeling index. The ratios of CK4- and CK13-positive staining were scored from 1 to 3. The CK4- and CK13-positive staining ratios were decreased in NNL (73% and 78%), LG-IN (55% and 69%), and HG-IN (33% and 48%), compared to NEE (91% and 95%). The differences between LG-IN and HG-IN, neoplasia and NNL, and among these three lesions and NEE were statistically significant (p < 0.005). The cytokeratin scores correlated with the MIB-1 labeling index (both: p < 0.0001), but not with p53 overexpression. CK4 and CK13 immunohistochemistry could be an objective method for evaluating the risk for progression to invasive carcinoma.departmental bulletin pape
Get PDFChronic hypersensitivity pneumonitis (HP) causes progressive and irreversible pulmonary fibrosis, a disease also observed in conjunction with idiopathic pulmonary fibrosis (IPF). Previous studies have demonstrated that the myofibroblast, a cell type whose origins involve the epithelial-mesenchymal transition (EMT), may play a role in the pathogenesis of IPF. The goal of this study was to determine whether EMT has a role in the pathogenesis of chronic HP. Lung specimens from a chronic HP model and from patients with chronic HP were analyzed. Cellular co-localization of epithelial and mesenchymal markers on the same alveolar epithelial cells (AECs) were examined using immunohistochemistry and cadherin switching by western blotting as indicators of EMT. EMT cells in the AECs were significantly more prevalent in lung specimens from Th2-prone A/J mice than in specimens from Th1-prone C57BL/6 mice. The percentage of EMT cells was correlated with the mRNA expressions of IL-13 and TGF-β1, the fibrosis score, and the collagen content in the A/J mice. In human, EMT cells in the AECs were significantly more prevalent in lungs specimens from patients with usual interstitial pneumonia pattern than in specimens from patients with nonspecific interstitial pneumonia pattern at the moderate stage of fibrosis. In conclusion, EMT may play an important role in the fibrotic process of chronic HP under the Th2-biased environment.departmental bulletin pape