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Get PDFChondrocyte differentiation is a fundamental process during endochondral ossification. Retinoic acid (RA) has been shown to regulate this process, however, the mechanisms underlying RA regulation of chondrogenesis are not clearly understood. Chondroprogenitor cells, ATDC5 have been shown to be a useful in vitro model for examining the multiple step differentiation of chondrocytes. The present study investigated the mechanisms underlying RA regulation of chondrogenesis using ATDC5 cell culture. In this study, we show that RA suppresses the cell growth, cartilage nodule formation, accumulation of proteoglycan, alkaline phosphatase (ALPase) activity and mineralization and that RA dose dependently upregulates the levels of type X collagen and matrix metalloproteinase-13 (MMP-13) mRNA which are marker proteins of hypertrophic chondrocytes, in ATDC5 cells. The addition of protein synthesis inhibitor, cycloheximide (CHX), partially inhibits the induction of type X collagen and MMP-13 mRNA by RA. In this system, RA upregulates the mRNA level of Runx2/Cbfa1 (type II), a positive regulator for mineralization, and downregulates the mRNA of Indian hedgehog (Ihh), parathyroid hormone related protein (PTHrP), negative regulators for terminal differentiation. However, RA downregulates ALPase, bone gla protein (BGP) mRNAs and mineralization. These data indicate that RA stimulates cartilage differentiation, however, cell condensation and cartilage nodule formation may be candidates of primary importance in the terminal differentiation of chondrocytes.departmental bulletin pape
Get PDFBACKGROUND: While the mechanism of aerophagia remains unclear, the frequency of clenching has been reported to be increased when under stress. We hypothesized that, via the swallowing reflex, chronic air swallowing was induced through a "learned habit" of the oral cavity, which was acquired through psychological factors. This study examined whether the habitual repeated swallowing in the oral cavity was a process of aerophagia. METHODS: After continuous experimental saliva swallowing, changes in the stomach bubble were examined by abdominal X-rays in a standing position. The subjects included 9 males and 10 females aged 20 to 36 years that were without organic disease in the pharynx and nasal cavity. X-ray images were digitized, and the area of the stomach bubble was measured by tracing. RESULTS: A close correlation was revealed in the stomach bubble area between posteroanterior and lateral views in six males (p<0.001, r = 0.910). In 3 males and 10 females, the area of the stomach bubble by posteroanterior view after 30 swallows was significantly increased compared with that before swallowing (p = 0.004). CONCLUSIONS: In the present study, abdominal X-rays confirmed that frequent saliva swallowing expanded the stomach bubble.departmental bulletin pape
Get PDFTissue conditioners are susceptible to colonization by microorganisms. Therefore, the prevention of biofilm formation are important for oral hygiene. However, mechanical and chemical cleaning methods may cause clinical problems such as deformation or surface degradation of tissue conditioners. The objective of this study is to evaluate the antifungal effects of coating agents with a TiO2 photocatalyst. Photocatalytic antifungal effects on C. albicans biofilms and photodegradation effects of adsorbed protein were measured by colorimetric assays. Scanning electron microscopy was used to examine morphological changes in C. albicans. Viscosities of coating agents increased with incorporation of TiO2. However, both of coating agents with TiO2 were acceptable to the application by brush. The antifungal and protein degradation effects increased with the concentration of TiO2 in the coating agents. These effects also increased with radiation time. After 90 min radiation, the viability of C.albicans was reduced to 16.2±3.3 %. Scanning electron microscopy observation showed C. albicans remained on the coated surfaces even after 90 min radiation. These results suggest that coating agents with TiO2 photocatalyst can be effective for the maintenance of tissue conditioners when dentures are removed; during sleep.departmental bulletin pape
Get PDFAims: The aims were to compare the sensory thresholds on the tip of the tongue with on the dorsum of the hand, and to investigate the relationship between the sensory threshold and depressive mood with volunteers whose psychological conditions were normal. Methods: Fifty-five subjects (28 women, 27 men) took psychiatric structured diagnostic interview and Self-rating Depression Scale (SDS). In the next step, the quantitative sensory tests (light touch sensation and thermal sensory test) were carried out on the tongue and the hand. Then we investigated the relationship between depressive moods and sensory thresholds on the tongue and the hand using logistic regression model. Result: The sensory thresholds on the tip of the tongues were significantly different from those on the dorsum of the hands. Only on tongue tip, increment of SDS had relation to the thresholds of innoxious thermal stimulation (OR=0.152, 95% CI. 0.049-0.478) and noxious heat stimulation (OR=0.352, 95% CI. 0.169-0.734). Conclusion: This finding might support for the idea that depressive mood had closer association with the tongue of the orofacial areas than the dorsum of the hand.departmental bulletin pape
Get PDFDespite wide spread use of the radial artery (RA) graft for coronary artery bypass grafting, the change of hand circulation after RA harvest has not been fully clarified. Severe hand ischemia such as resting pain or gangrene is a rare complication and has been reported in 4 patients. These cases resulted from occlusive artery disease in forearm, which should be carefully explored before RA harvest. Incidence of mild hand ischemia such as hand claudication or fatigue is unknown, but our study suggested that around 10% of the patients developed mild hand ischemia after RA harvest. The blood flow to the forearm territory was decreased by 20% after RA harvest despite the compensatory dilatation of ulnar artery. The presence of low perfusion in the affected hand has been pointed out in some studies. We reported the decreased tissue oxygenation of the affected hand during hand grip exercise. The Allen test is the most popular preoperative screening method, but is associated with considerable numbers of false-positive and falsenegative results. Full length scanning of ulnar artery by ultrasonography seems to have a lower false-positive rate. But further clinical experience is necessary to establish a more reliable screening method.departmental bulletin pape
Get PDFThe ideal dressing material is bio-inert and keeps the wound site moist. It is equally important that no regenerative tissue is peeled off on the removal of the dressing. 2-Methacryloyloxyethyl phosphorylcholine (MPC) has a phospholipid polar group that mimics a biomembrane. We prepared poly [MPC-co-n-dodecyl methacrylate (DMA)] (PMD), using conventional radical polymerization with 2,2'-azobisisobutyronitrile as an initiator, and coated it on polyurethane (PU;Tecoflex® 60 Thermedics Inc.) membrane. Fullthickness surgical wounds were made on the dorsal skin of rats and wound healing was compared under the following three conditions: air-exposed control (no dressing), PU dressing, and PMD dressing. At 3, 4 and 7 days after the operation, the wound sizes of the PMD dressings were smaller than the non-dressed wound, and at 6 and 7 days after the operation, the wound sizes of PU dressing were smaller than that of the air-exposed group. But there were no significant difference between the PMD dressing group and PU dressing group. Histologically, scab formation was not observed on the PU or PMD-dressed wounds. However, in the air-exposed control, a scab was formed and reepithelialization of the wound site was prevented. Additionally, no damage was observed in the histological section of PMD dressed wound after the wound was cured. These results indicate that PMD dressing (PMD-coated PU membrane) has the potential to provide an inert environment for wound healing as well as PU.departmental bulletin pape
Get PDFHuman herpesvirus-6B (HHV-6B), a causative agent of exanthem subitum, infects human adult T cell leukemia (ATL) cell lines. We established a persistent HHV-6B infection in an ATL cell line, TaY, in the presence of 20 units/ml interleukin-2 (IL-2). The HHV-6B infected culture proliferated with a constant ratio of infected (1%) to the uninfected (99%) cells. When the IL-2 concentration was reduced to 5 units/ml, the number of infected cells in the culture increased transiently by 60% in 11 days, a new balance of 25% infected cells and 75% uninfected cells was established thereafter. PCR analysis confirmed a 125-fold increase in the amount of viral genome in the culture, while the treatment with ganciclovir reduced the proportion of infected cells, indicating that an efficient replication of virus was induced in the culture. Both of these cultures were maintained in the presence of 20 or 5 units/ml IL-2 over one year without loss of infected cells. Interestingly, we found that cultures containing the infected cells grew significantly faster than the parental uninfected cells at the same concentration of IL-2. The infected culture continued to grow for 7 days even in the absence of IL-2. Because the infection induces cell cycle arrest, these results indicate that the HHV-6B-infected ATL cells stimulate the growth of the uninfected cells during persistent infection in culture.departmental bulletin pape
Get PDFBackground: It is unknown whether insurancestatus influences care provided and patients'prognosis, in China.Methods: This retrospective cohort studyincluded medical records of 4,714 patients withacute myocardial infarction aged 20 and older,discharged consecutively from 14 Chinese hospitalsbetween January 2000 and February 2003.Uni-variate analysis, multivariate logistic regressionand linear regression were used to compare differencesin patients' characteristics, care providedand prognosis between insured patients and theuninsured.Results: The uninsured were more likely to beolder, female, have transfer admissions, and lesslikely to be hospitalized to institutions with cardiacinterventional facilities, intensive care units orcoronary care units. The uninsured were also lesslikely to undergo diagnostic procedures, interventionsand to receive medications, and stayedshorter in hospital and consumed less health careresources. In-hospital mortality in the uninsured,the non-government insured and the governmentinsured was 10.5%, 12.2% and 8.4% respectively.After adjusting for potential confounders, oddratio in hospital mortality was 1.079 (95% CI,0.836–1.392) and 0.763 (95% CI, 0.559–1.041) for thenon-government insured and the governmentinsured, compared to the uninsured. At significantlevel of 0.05, we could not assert insurance statusis a significant factor to in-hospital mortality.departmental bulletin pape
Get PDFIn this study, patients with heart diseases were classified into 2 groups: Warfarin user and Warfarin non-user, and six salivary components were determined to assess intraoral pathologic conditions. Groups of healthy subjects and patients with periodontal disease without receiving any medication were set as control groups, and they were compared with those of the 2 groups with heart diseases. In patients with heart diseases in both the groups, albumin (ALB) level was found to be significantly higher compared to that in the control groups, and it was significantly higher in the patient group receiving Warfarin user and Warfarin non-user compared to that in the patient group with periodontal disease. C-reactive protein (CRP) levels were found to be higher in both the groups with heart diseases than those in the healthy group. Correlations between various salivary components and the clinical parameters were examined, showing significant correlations between ALB and gingival index (GI) and clinical attachment level (CAL), and between alanine aminotransferase (ALT) and GI, probing depth (PlI), bleeding on probing (BOP) and CAL. Significant correlations were also found between creatine kinase (CK) and PlI, GI and BOP. Thus, it was suggested that ALB and CRP might serve as the markers of intraoral pathologic conditions, and CK and ALT might serve as those alternative to GI.departmental bulletin pape
Get PDFBackground: Public Health Centers (PHCs) throughout Japan have been playing a role in preventing HIV in Japan. The number of HIV seropositive persons and AIDS patients is increasing from year to year in Japan. Methods: A survey regarding the HIV antibody test was sent out to 594 PHCs between January 1997 and December 2001. The response rate was 73.9%. In order to assess the HIV testing system at PHCs, Pearson's correlation coefficient, an analysis of variance (ANOVA) and multiple regression analysis were used. Results: There was a difference in the demand for HIV antibody tests according to area. The change in number of HIV antibody tests per 100,000 persons was high in metropolitan areas during the 5-year period. It was influenced by two factors; population density and ratio of daytime population to nighttime population. Rate of examinees who did not return to receive their test results was influenced by the area where the PHC was located. Conclusions: PHCs need to establish an HIV testing system which reflects the characteristics of the area and meets the needs of people who want to get tested.departmental bulletin pape