Many high mountaineers die of acute mountain sickness in the high mountains of Nepal during their adventure. Most of them administer acetaminophen (AP) as an analgesic. Various cells with higher expression of cytochrome P-450 (CYP) would metabolize AP and lead to cellular impairment. CYP is a major enzyme system in the metabolism of xenobiotics in different organs of the human being including in Clara cells of the lungs. Clara cells contain the highest concentration of CYP. We injected AP to C57BL/6J mice to examine the toxicity of AP in Clara cells. In 8 hours Clara cells show more prominent apical protrusion with edematous smooth endoplasmic reticulum (sER), reduced secretary granules, and edema. We speculate that using AP in a high mountain area might be harmful for Clara cells being a trigger of high altitude sickness.

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The effects of high extracellular calcium (high Ca) in the local microenvironment on osteoclasts, osteoclast progenitors and stromal cells are not fully understood. We examined high Ca effect on osteoclastogenesis in mouse bone marrow cell culture. Mouse bone marrow cells were cultured for up to 6 days in the medium supplemented with 1,25(OH)₂ vitamin D₃ (D3). High Ca treatment at the early stage of culture (the initial 24 hours) reduced the number of tartrate resistant acid phosphatase-positive multinuclear cells (TRAP(+)MNCs). This treatment slightly up-regulated the mRNA expressions of receptor activator of NF-(B ligand (RANKL), RANK and osteoprotegerin (OPG). This inhibitory effect on the formation of TRAP(+)MNCs was recovered by RANKL. In contrast, high Ca treatment at the later stage of osteoclastogenesis (the last 2 days of culture) stimulated the formation of TRAP(+)MNCs, increased RANKL and RANK mRNA expressions and decreased OPG mRNA. High Ca at neither the early nor the later stage of culture affected the total number of adherent cells and the mRNA expression of alkaline phosphatase and osteopontin. In conclusion, high Ca affects osteoclastogenesis in a manner depending on the stage of osteoclastogenesis, which is partly mediated via the RANKL-RANK-OPG regulatory system.

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The purpose of this study was to investigate the effect on the vibratory characteristics of a cast hollow obturator prosthesis retainer when varying its bulb height. Bulb parts with high (H), middle (M), and low (L) lateral walls were prepared. A Vibration Generator was used to excite the three obturators, while a Laser-Doppler Vibrometer was employed to detect the vibrations at specified measurement points. The frequency response functions of each obturator were recorded on an FFT analyzer to enable their modal shapes to be identified. In addition, transient response simulations were carried out and the decay rate (DR) and the maximum amplitude (MA) of the rest and clasp parts of each obturator were obtained. These were statistically analyzed by ANOVA and Fisher's PLSD test (p < 0.01). The modal shapes were almost the same in all obturators. Significant differences were found in DR in all pairs among the three obturator prostheses, with the DR of the L type being the highest. On the other hand, there were no significant differences in MA. We conclude that the L type is preferable from the standpoint of its vibratory characteristics.

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Using a modal analysis system, we carried out a comparative assessment of the vibratory properties of the maxillary dentition of a human dry skull with a different distal end of a mouthguard. Mouthguards used in this study were: 1. a mouth-guard covering up to the third molar (8MG), 2. the second molar (7MG), 3. the first molar (6MG), and 4. the second premolar (5MG). To identify the modal shape, the frequency response functions were recorded on a fast Fourier transform analyzer from the force signal impacted with a vibration generator and the response signal picked up using a laser-doppler vibrometer. The transient response waves were obtained throughout the transient response simulation procedures after curve-fitting procedures. Mean decay rates (sec^-1) of the transient response waves were calculated for the anteriors, premolars and molars, and compared among different sets of experimental conditions. The decay rates became lower as the distal end of a mouthguard was short. The decay rates with 8MG, 7MG and 6MG (anteriors) exceeded the no mouthguard's decay rate + 2S.D. values. These results imply that a mouthguard should distally cover up to the second molar at least to ensure efficient absorption and/or dispersion of a traumatic force.

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(Object) Endovascular treatment with Guglielmi detachable coil has been developed as a less invasive treatment for cerebral aneurysm. The aim of this study is to clarify the mechanism of the preventive effect of coil embolization. (Method) Two aneurysm models were employed. One was a T-shaped bifurcation tube with a spherical dome made of glass, which was used for the measurement of pressure and visualization of flow pattern. The other model was a T-shaped glass tube with a spherical elastic silicone dome, which was used for the measurement of aneurismal wall displacement due to pulsation of flow. (Result) 1, Guglielmi detachable coil caused no change in intra-aneurismal fluid pressure. 2, Coil insertion obstructed and slowed intra-aneurismal flow. This flow stagnation in the aneurysm might promote thrombus formation. 3, With increase in numbers of coils anchored at the intra-aneurismal wall, the displacement of the wall was considerably depressed. This suggests that coil insertion decreases the stress on the aneurismal wall. (Conclusion) 1, Coil insertion depresses the pulsatile aneurysm wall movement, and diminishes the stress of the aneurysm wall. 2, Coil insertion obstructs intra-aneurismal flow and facilitates thrombus formation in the aneurysm. These two factors may operate synergistically to prevent aneurysm rupture.

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This study examined the effects of conditions (that is, the fee structure and the easy of obtaining a dental appointment) on patient understanding and cooperation in clinical practice for dental hygiene and dental students. A questionnaire was given sequentially to 1483 patients attending the Tokyo Medical and Dental University dental hospital on "clinical education and patient satisfaction". Direct participants consisted of 650 patients, of which 213 (32.8%) were male and 422 (64.9%) female. The remaining 15 (2.3%) did not specify their gender. Patients who were satisfied with care received by dentists tended to be older compared to patients who were dissatisfied with dentists. The difference was significant (p < 0.001). Acceptable conditions for patients such as fees and appointments at the clinical session had an effected on patient acceptance of clinical training. The findings of this study suggest that patient satisfaction should be considered as part of the reasons for patients accepting dental care by students in their clinical education programs. Fees and appointment schedules strongly affect patient acceptance of clinical education.

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The purpose of this study was to examine effects of a denture adhesive on masticatory functions for complete denture wearers considering the condition of denture-bearing tissues. Sixteen edentulous subjects wearing well-fitting complete dentures volunteered to participate in this study. According to the condition of denture-bearing tissues, subjects were divided into two groups; "good group" and "poor group". Maximum biting forces, masticatory performance, and electromyography of the masseter muscle during mastication were recorded with and without a denture adhesive. Durations of chewing burst and cycle, and coefficients of variation for these variables were calculated using electromyography recordings. Data were analyzed by using two-way repeated-measured ANOVA and paired t-test in order to assess the effect of the use of a denture adhesive. The use of the denture adhesive increased maximum biting force and provided rhythmic masseter muscle activity during mastication for both groups. Masticatory performance was improved and duration of chewing burst was decreased only for "poor group". It was concluded that the effects of the denture adhesive on masticatory functions were observed overall for both groups, and more significant for denture wearers with poor denture-bearing tissues than with good denture-bearing tisuues.

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A new rehabilitation (New-RH) program including respiratory muscle stretch gymnastics (RMSG) was developed to alleviate post-coronary artery bypass grafting pain (PCP). Effects on respiratory muscle function, pain, activities of daily living (ADL), mood and exercise capacity were investigated. Subjects were 16 consecutive patients undergoing median full sternotomy coronary artery bypass grafting (CABG), and were randomly divided into equal New-RH (S-group) and conventional therapy (C-group) groups. Rib cage dominant breathing was observed postoperatively in both groups. With preoperative tanΔVrc/Δ Vab, increases at 1-week postoperatively and decreases at discharge for S-group tended to exceed those of C-group (p > .05). Decreased maximum inspiratory and expiratory pressure status for functional residual capacity and percent forced expiratory volume in one second at discharge again only tended to be smaller for S-group (p > .05). S-group displayed significantly reduced pain around both scapulas at discharge (p = .049), and increased mean overall ADL and profile of mood states (POMS)/Vigor scores (p = .031 and p = .018, respectively). POMS/Tension-Anxiety scores at discharge for S-group were significantly smaller than those preoperatively (p = .025), and S-group displayed significantly increased distance walked over 6-minutes at discharge than C-group (p = .029). New-RH improves patient participation in exercise therapy and increases exercise capacity by reducing PCP, relieving anxiety and tension, and improving ADL.

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This article describes the prosthodontic treatment for a patient with cerebral palsy, in which complete dentures were successfully stabilized using treatment dentures. A 69-year-old edentulous male with no medical complications or mental retardation presented to our clinic. Opening movement of the jaw was possible, but a conspicuous mandibular shift towards the right was observed. He had never received any prosthodontic treatment. Initially, treatment dentures with flat tables were fabricated to rectify his erratic mandibular movements. During the first 3 weeks, the treatment dentures functioned poorly. Eventually, the patient could make tapping movement to some degree and have a meal with less effort. Indentation marks from the cusps of the opposing maxillary denture could be clearly seen on the flat tables. After six weeks, as he did not complain of any pain, definitive dentures were fabricated. When flat table treatment dentures are used, it is considered that the mucosa provides information regarding the vertical stop and bite force. In addition, it is speculated that there is an increase in the response from masseter muscle. In the present case, flat tables were effective for rehabilitation of the mandibular movement.

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