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Get PDFAlthough human bone marrow stromal cells (MSCs) have been used for clinical bone reconstruction, how the physiological status of patients and culture conditions of MSCs affect the result of bone reconstruction must be clarified to use MSCs in a clinical stage. If in vitro parameters of the status of MSCs may be correlate with in vivo bone formation capability, the better cells for clinical bone reconstruction can be defined by the parameters. In order to explore the parameters and define the optimum cells for clinical use, the proliferation and differentiation capabilities in vitro and the in vivo bone formation capability of MSCs were analyzed. An age-related proliferation capability was found. The in vitro alkaline phosphatase activity of bone formation finding groups was higher than that of the no bone formation group. This may be provide a parameter to obtain the optimum cells for clinical use to benefit improving the cure efficiency. In this study, it is preferable that MSCs of passage 1 have stronger osteogenic potential than those of passage 2 and 3 in vitro, and might be suitable for clinical application to bone tissue engineering.departmental bulletin pape
Get PDFIt has been reported that occlusal forces promote periodontal healing of transplanted teeth and prevent dentoalveolar ankylosis, although its mechanism is still unclear. Nitric oxide (NO) produced by NO synthase (NOS) is considered to be an important factor which is involved in wound healing, and it increases with mechanical stimuli. The objective of this study was to examine the relationship among occlusal stimuli, inducible NOS (iNOS) and PDL healing of transplanted teeth. Five-week-old Sprague-Dawley male rats were used for this study. The right maxillary first molars of rats were replanted and animals were divided into occludedand non-occluded groups. Histologic observations were carried out after one and two weeks. After two weeks, the non-occluded group had clearly detectable ankylosis and obvious PDL stricture. On the other hand, the occluded group showed an enlarged and thickened PDL without ankylosis. The number of iNOS positive cells in the occluded group, samples significantly increased in comparison to that of the non-occluded group. These results suggest that occlusal stimuli enhanced the production of NO in the PDL healing process of transplanted teeth and a favorable result could be obtained.departmental bulletin pape
Get PDFWe assessed the feasibility of clonality analysis with human androgen receptor gene polymerase chain reaction in terms of the sensitivity and specificity for normal and cancerous colonic tissues taken from fourteen informative cases selected from 22 women with colonic adenocarcinoma. Ten crypts microdissected from each 10-µm-thick cryostat sections and whole tissues were used as samples. DNA was extracted from the samples and amplified with and without prior enzyme digestion. These products were analyzed by capillary electrophoresis for clonality. Of the whole-tissue DNA, none of the normal tissues and seven (50.0%) of the cancerous tissues showed monoclonality. Of the microdissected samples, monoclonality was found in 88.4% (107/121) of normal crypts and 95.9% (117/122) of cancerous crypts. Samples composed of crypts with short and long alleles were found in eight of the 14 normal colonic mucosae, but in none of the cancerous tissues. We concluded that the sensitivity of this method is limited for both whole-tissue DNA and microdissected-tissue DNA, because monoclonality from small samples does not always indicate monoclonality of the entire lesion. The high specificity of this method, however, allows polyclonal results in whole tissues to be confirmed by additional analysis of microdissected tissues.departmental bulletin pape
Get PDFGlomerular visceral epithelial cells orpodocytes are located on the outer surface of theglomerular basement membrane and play anindispensable role as a filtration barrier. The corecytoskeleton of the foot processes is actin filaments,which play an important role in maintainingthe unique structure of podocytes. We previouslyestablished a transgenic mouse line(NEP25), which expresses human (h)CD25 selectivelyon podocytes. By injecting an hCD25-targetedrecombinant immunotoxin (LMB2), podocyteinjury can be induced on demand. After LMB2injection, NEP25 mice develop nephrotic syndromewith downregulation of podocyte-specificproteins. In the present study, we geneticallylabeled podocytes with lacZ linked with β-actin-basedCAG promoter. Utilizing the Cre-loxP system,this labeling was confined to the podocytelineage. Without LMB2, all podocytes were positivefor lacZ. After LMB2 injection, lacZ expressionwas rapidly downregulated, before podocytesshowed any discernible morphologicalchanges. Confocal imaging of filamentous (F)-actin-binding Alexa 488-phalloidin revealed thatthe normal continuous pattern of F-actin distributionin podocytes was punctuated after LMB2injection. These collectively suggest that disturbanceof actin filaments may be one of the key initialevents leading to subsequent podocyte damage.departmental bulletin pape
Get PDFPurpose: The purpose of this study was to clarify the influence of changes of occlusal contacts on adjacent tooth displacement during articulation. Materials and Methods: The amount and direction of displacement of the maxillary left first molar and adjacent teeth were measured using a displacement transducer, Type M-3. Seven subjects were included in this study. On the maxillary left first molar, 8 experimental occlusal contact points were established using platinum foil and these were divided into 2 groups, the buccal and lingual groups, which corresponded to the buccal and lingual cusps, respectively. Results: During clenching, the buccal group showed differences in the direction of the tooth displacement paths among the 3 teeth (second premolar, first and second molar), but there was no difference in the lingual group and the direction of displacement of these 3 teeth was similar to the natural teeth. Conclusion: It is necessary to make at least one lingual occlusal contact point to obtain displacement of not only the abutment tooth but also the adjacent teeth.departmental bulletin pape
Get PDFThe purpose of this study was to evaluate the generation of enamel cracks and gaps at the cavosurface margin of resin composite restorations using various burs. Saucer-shaped cavities with a bevel were prepared on mid-coronal buccal or lingual surfaces of extracted human molars using a regular-grit round diamond bur, a fine-grit diamond bur, a superfine-grit diamond bur or a sixbladed tungsten carbide bur with an air turbine handpiece. The enamel margin of the cavity in each group was observed by a light microscope. Cavities were restored with a self-etching adhesive and a light-cured composite resin. After thermocycling, enamel cracks and gaps at the cavosurface margins were observed and scored. Specimens were sectioned longitudinally in two halves, and the resin-cavity interface was observed by means of a light microscope. In cavity preparation, the regulargrid diamond bur and the tungsten carbide bur caused more cracks in the marginal enamel than other groups. From the surface and sectioned surface observation of restored teeth, the superfine-grit diamond bur generated fewer cracks and gaps than the other burs.departmental bulletin pape
Get PDFAlong with the popularization of endoscopic surgeries, the reuse of disposable single-use devices (SUDs), which may cause various risks, has become a considerable issue globally. We conducted the survey by questionnaires for the operating room (OR) head nurses to obtain hospital-based answer. First survey was done for three months in 2000 by sending the questionnaires to 2,224 hospitals. The second survey was done in 2003. In addition, for trocars and endoscopic clips, we carried out laboratory functional tests for the reuse of these reprocessed devices. As a total, 94.4 % of hospitals reused SUDs routinely. The second survey showed significant decrease in the frequency of reuse to 86.2 % as a whole. In the sample study, gross inspection showed the existence of contamination with debris. In-vitro sample study on in-hospital reprocessed instruments also demonstrated damaged endoscopic clips with impaired holding power. This study has demonstrated a still high frequency of reuse of SUDs in endoscopic surgeries in Japan. Although financial background may be the main reason, what is necessary to promote the single use of SUDs are multidisciplinary and composite approaches including an effort to lower the product price in parallel with the establishment of regulation and education programs.departmental bulletin pape
Get PDFSuppression subtractive hybridization is very effective to enrich differentially expressed genes in two different tissues or cells. We therefore used the technique to identify characteristic genes expressed in rat knee joint articular cartilage as compared to rat costal cartilage. In this study, we revealed that several genes were enriched in a subtracted articular cartilage cDNA library. The most enriched gene is lubricin that is a putative key molecule for joint lubrication. The second gene is milk fat globule epidermal growth factor (EGF) factor 8, MFG-E8 whose expression has never been observed in cartilage. Other enriched genes are known to be expressed in cartilage, however their differential expressions in cartilages have not been necessarily common. The preferential expression of characteristic genes in articular cartilage would provide unique properties to the tissue. Our findings will provide a new view of articular cartilage.departmental bulletin pape
Get PDFExogenously added granulysin was reported to kill mammalian target cells. The sites of actions and molecular mechanisms of granulysin in target cell killing, however, are presently unclear. We here examine the effects of granulysin with the target HeLa cells transiently expressed with GFP-fused 9 kDa granulysin. Endogenously expressed GFP-fused granulysin was preferentially localized in the nucleus and induced apoptotic cell death accompanying with phosphatidylserine translocation and nuclear condensation in a caspase-independent manner. These results suggest that granulysin enters the nucleus of target cells and induces apoptosis.departmental bulletin pape
Get PDFDue to large individual differences of masticatory function, an inter-individual comparison between denture patients and complete dentate people would be insufficient. This cross-sectional study aimed to evaluate patients' masticatory performance (determined by Mixing Ability Index, MAI) and bite force (determined by maximum bite force, MBF) after removable partial denture (RPD) treatment by comparing those of the RPD replaced side with those of their own opposite dentulous side, and to evaluate influence of bite force on masticatory performance in different dentitions. Subjects included patients with unilateral distal extension RPDs (n=28). Apart from the RPD replaced area on one-side, all subjects had intact dentitions. Both masticatory parameters were evaluated separately on each chewing side. MAIs and MBFs obtained from the RPD replaced side (0.65 ± 0.50 and 220 ± 155 N, mean ± SD) were significantly lower than those from the dentulous side (1.06 ± 0.64 and 450 ± 268 N; Wilcoxon signed-ranks, P<0.001). MBF significantly influenced MAI in both RPD replaced (Univariate linear regression; R2=0.17, P< －0.001) and dentulous sides (R2=0.51, P< 0.001). After RPD treatment, masticatory performance and bite force of RPD replaced side were lower than those of their own dentulous side. The influence of the bite force on masticatory performance in RPD replaced side was less significant than that in the dentulous side.departmental bulletin pape