BACKGROUND: 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.

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Background: 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.

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In 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.

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Purpose: The aim of this study was to evaluate the expression of cyclooxygenase-2 in human breast cancer using immunohistochemistry and to determine whether the expression of cyclooxygenase- 2 is associated with clinicopathological factors in invasive ductal breast carcinoma. Methods: Cyclooxygenase-2 expression was investigated by immunohistochemistry in 30 invasive ductal breast carcinoma specimens and relationships between cyclooxygenase-2 expression and age, histological grade, histological type, nodal status, and hormone receptor status were evaluated. Results: Cyclooxygenase-2 expression was found in 56.7% of the tumor samples and was related to histological grade (P<0.01) and histological type (P<0.001). Conclusions: Our results suggest that cyclooxygenase-2 expression has an important role in tumor differentiation in invasive ductal breast carcinoma.

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Purpose: 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.

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Suppression 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.

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We examined the associations between prefectural health status of children and sanitation infrastructure, medical care services and socioeconomic status in Japan during 1955-2000. Four indicators of child health status: infant mortality rate (IMR), Ascaris lumbricoides prevalence and height and weight of elementary school children, and five prefectural social indicators: water supply, sewerage, number of physicians, income and women’s education, were calculated over fiveyear intervals and examined by correlation and panel data analyses. Associations between paediatric health and five social indicators were significant (p<0.001) until 1970. After adjustment for income or education, water supply diffusion rate showed a significantly negative association with IMR until the 1980s. A significantly positive correlation was observed between the number of physician and paediatric health from 1955-70 after adjustment for income. Water supply development showed a positive association with paediatric health after adjustment for economic or educational impact during the phases of rapid and steady economic growth, while medical care showed a positive correlation with paediatric health after adjustment for income during only the phase of rapid economic growth. Relationships between child health status and social indicators have changed over time with stage of economic development.

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Tissue 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.

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If the quality and efficiency of medical services are to be ensured, electronic health records (EHR) and EHR-supporting infrastructure must be prevalent. Many hospitals, however, have EHR systems for their internal use only, and the standardization process for the exchange of medical information is still in process. This standardization process addresses information security and is considering public key infrastructure (PKI) as one security measure, but PKI is rarely used by medical practioners because of its poor user-friendliness. Here we propose an effective use of the identitybased encryption (IBE) system as a security measure. This system enables us to send encrypted and signed messages without requiring the receiver to get a public key, and it enables us to deliver secured messages to ambiguous receivers like those to whom letters of reference are sent. We evaluated the feasibility of this technology by using the analytic hierarchy process, which is an effective analysis tool when selection and judgment depend on nonquantitative psychological factors, to analyze the results of an experiment in which medical workers used E-mail agents with and without PKI and IBE. We found that medical practioners and researchers avoid using PKI because of its poor user-friendliness and instead use IBE even though it is harder to install. We therefore think IBE would encourage medical institutions to share patient records.

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