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Get PDFWe investigated differences in the depth of hypoxia produced by apneic events of the same duration (30 seconds) amongst patients with different degrees of OSAS according to their AIs (apnea indices). The relationship between apnea duration (seconds) and fall in oxygen saturation (%) was evaluated by means of a linear regression analysis. The fall induced by a 30-second apnea event was designated as the "oxygen desaturation value 30" (ODV30). We analyzed the polysomnographic recordings of 122 OSAS patients who showed significant correlations (p<0.01) between apnea duration and subsequent fall in oxygen saturation and calculated their respective ODV30. We evaluated the influence of AI and BMI on ODV30 by multi-comparison and found out that standardized partial regression coefficients of BMI and AI were 0.578 and 0.148, respectively (multi-regression analysis, SPSS). BMI was proved to be more influential on ODV30 than AI was. On the other hand, the ODV30 of mild, moderate and severe OSAS patients was 8.84 ± 2.62% (Mean ± S.D.), 8.25 ± 2.45% and 10.59 ± 3.32%, respectively. Our study shows that fall in oxygen saturation is particularly extensive in severe OSAS patients and that fall in oxygen saturation is deepened as obesity increases. We think ODV30 is a useful variable for evaluating OSAS.departmental bulletin pape
Get PDFWe developed a honeycomb-shaped lyophilized Type I atelocollagen (Honeycomb Collagen: HC) with different pore sizes, and the effectiveness of the honeycomb shape on nerve regeneration was examined. We analyzed neurite outgrowth of dorsal root ganglion (DRG) explants on HC, both in vitro and, with direct implantation of HC into thedefects of adult rat spinal cords, in vivo. The neurites of DRGs on HC extended linearly through the pores. HC with a 400 µm-pore size enhanced neurite extension, and YIGSR laminin peptide coating to the HC extended more neurites than fibronectin coating. The HC scaffolds coated with YIGSR were implanted into 2 mm-defects of spinal cords at the level of T8-9. Four weeks after implantation, the implants had degraded and been replaced with self-tissues, repairing the injured site. Neurofilament-positive fibers were observed in the implantation area and passed the borders between the HC and spinal cord stumps. Functionally, a motor-evoked potential was observed in the quadriceps femoris muscle 10 weeks after implantation. The electrophysiological examination showed reconstruction of axon tracts over the implant. This result indicates that our developed honeycomb shape is advantageous for host spinal cord compared to the random pored sponge shape, and that it promotes axonal regeneration after spinal cord injury.departmental bulletin pape
Get PDFSo far, pentazocine iontophoresis has never been studied, although pentazocine is widely used in pain management. The purpose of this study was to determine whether pentazocine transportation through a cellophane membrane could be enhanced using square-wave alternating current (AC) iontophoresis with an adjusted duty cycle and dependence on the voltage and the duty cycle. Voltages of 10, 25 and 40 V with duty cycles of 50%, 51%, 52%, 53%, 54% and 55% were applied for 60 minutes at a high frequency of 1 MHz to diffusion cells on both sides of a cellophane membrane. The donor compartment was filled with a solution containing pentazocine. Squarewave AC iontophoresis with an adjusted duty cycle enhanced pentazocine transportation at higher voltages and duty cycles. These results suggested that the direct current (DC) component of the square-wave AC played an important role in enhancing pentazocine transportation despite changes in polarity at very high frequency of 1MHz. The higher voltages and duty cycles induced a pH change. The practical electrical conditions that could be applied clinically were 25 V with a 54% duty cycle or 40 V with a 53% duty cycle.departmental bulletin pape
Get PDFIn recent years, ubiquitous computing technologies have been applied in the field of medicine. Especially radio frequency identification (RFID) and small sensor networks could provide information about medical practices and patient status in order to prevent malpractices and improve the quality of medical care. As an example of this application, we developed a new system, named "a smart stretcher," which continuously monitors the patient's vital signs and detects apnea during transfer within a hospital. This system consists of asmall air-mat type pressure sensor measuring both heart rate and respiration rate and a wireless network transmitting these vital data as well as patient ID to an alerting system to notify hospital staff of patient emergencies. Results of experiments in a clinical setting indicated that the system was reliable in continuous respiration monitoring and detection of apnea during patient transfer on the stretcher; however, detection of heartbeat rate was practically difficult because of the motion noises. Moreover patient ID and location were also correctly detected in real time. These results suggested the feasibility of our system for real clinical use.departmental bulletin pape
Get PDFThe meniscus is semilunar fibrocartilage, and itsinjury causes dysfunction of the knee. We previouslyreported a high chondrogenic potential ofsynovial mesenchymal stem cells (MSCs). Here, weexamined whether intra-articular injected synovialMSCs adhered to the defect of the meniscus, survivedthere, and differentiated into cartilage cells.MSCs were isolated from the synovium of GFP rats.Cylindrical defects were created in the menisci inwild rats, and GFP-positive synovial MSCs wereinjected into the knee. In the control group, 100 μlof PBS was injected into the contralateral knee. Themenisci were analyzed after day 1, weeks 2, 4, 8,and 12. One day after injecting of 107 GFP-positivesynovial MSCs, the meniscal defect was filledwith the cells. The GFP-positive synovial MSCsexpressed type II collagen, exhibited representativecharacteristics of chondrocytes by electronmicroscopy at 8 weeks, and could still beobserved at 12 weeks. The histological scoreimproved within 12 weeks but there were no statisticaldifference between the two groups at eachperiod in this model. GFP mRNA expressionswere not observed in distant organs at day 1.After intra-articular injection, synovial MSCsattached to the meniscal defect and differentiatedinto cartilage cells.departmental bulletin pape
Get PDFThe mechanical properties of dentin are changed after bleaching, although the effects of the bleaching conditions on the tensile strength of dentin have not been determined. In the current study, a tensile test of bovine dentin was conducted after bleaching and the effects of the bleaching conditions were investigated, including the number of bleaching times, the location where the bleaching agent was applied, and the kind of illumination. The weight of organic content in dentin before and after application of the agent was also measured. The results showed that the tensile strengths did not change after three times office bleaching procedure, and the location where the bleaching agent was applied, the kind of bleaching agent and the kind of illumination did not have influence on the tensile strength. On the other hand, organic component in dentin significantly decreased after application of the agent (p<0.05). Since the bleaching agent would potentially affect tensile strength with deterioration of collagen matrix, the frequency of bleaching treatment should be minimized in clinical use.departmental bulletin pape
Get PDFAim: T cell-mediated immunity is involved in the pathogenesis of atherosclerosis and arteriosclerosis. This study examined whether the 4-1BB pathway affects the development of arteriosclerosis after vascular injury. Methods and Results: The left or right femoral arteries of adult male mice weighing 22 to 25 g were injured with a straight spring wire. The injured artery was excised 28 days later. Confocal microscopy revealed intense expression of both 4-1BB and 4-1BBL in the developing neointima and media. Similar results were obtained on immunoblotting analysis of lysates of the injured arteries. We gave mice an injection of 100 μg or200 μg 4-1BB-fused with human immunoglobulin (Ig) every other day over the course of 5 days. As compared with untreated controls (intima/media ratio, 2.13 ± 0.37, n=10), the intima/media ratio was smaller in mice treated with 200 μg of 4-1BBIg (1.20 ± 0.30, n=6, p<0.05), but not in mice treated with 100 μg of 4-1BBIg (1.56 ± 0.27, n=9). Conclusions: 4-1BB inhibits neointimal hyperplasia after vascular injury. Our findings suggest that 4-1BB is involved in injury-induced neointimal hyperplasia and may be an effective target for the treatment of neointimal hyperplasia.departmental bulletin pape
Get PDFScleroderma is a fibrotic condition characterized by immunological abnormalities, vascular injury and increased accumulation of extracellular matrix proteins in the skin. Although the etiology of scleroderma has not been fully elucidated, a growing body of evidence suggests that the overproduction of extracellular matrix proteins by activated fibroblasts results from an imbalance between synthesis and degradation of connective tissues. A number of mediators, cytokines, chemokines and growth factors secreted by inflammatory cells and mesenchymal cells (fibroblasts and myofibroblasts) play an important role in the fibrotic process of scleroderma. In this article, we describe recent advances concerning immunological aspects in the pathogenesis of bleomycin-induced murine scleroderma, laying stress on the involvement of interleukin-13 (IL-13) and plasminogen activator inhibitor-1 (PAI-1).departmental bulletin pape
Get PDFThe effect of different polishing materials on the surface texture and the color change of indirect prosthetic resin composite materials exposed to a staining agent was studied. Six different resin composites were polished using the same procedures and were measured for the gloss. After exposed to a coffee solution, the changes were measured on the color properties. The six different types of resin composites were further divided into four groups of eight specimens each for the different surface polishing procedure. The gloss was measured by a gloss meter (TC-108D, Tokyo-Densyoku, Tokyo, Japan) with an angle of 45° and expressed in gloss units (GU). Before and after exposure to the staining agent, the color measurements of all specimens were recorded with a colorimeter (TC-1800MKII, Tokyo-Densyoku, Tokyo, Japan) using CIE L* a* b*. All specimens were stored in the coffee solution for 5 weeks at 37 °C. Most of the resin composites showed the highest gloss and staining resistances when the fine silicone diamond polishing point was used. The results of this study suggested that there are differences in the gloss and the color changes depending on the filler type and the composition of the polishing materials.departmental bulletin pape
Get PDFBone marrow stromal cells (MSCs) have multi-lineage differentiation capabilities and are focused on as a cell source for various cell therapies. To facilitate the availability of MSCs, cryopreservation technique is one of the critical factors for the celltherapies. In this study, effects of cryopreservation on capabilities of MSCs derived from a nonhuman primate were tested, aimed at a clinical application for tissue-engineered bone reconstruction. Effects of cryopreservation on the MSCs' adhesion rate, proliferation, and osteogenic differentiation in vitro were compared with non-cryopreserved MSCs. Bone formation capabilities were also tested using an extraskeletal bone induction model. The bone formation inducted by the combination of cryopreserved MSCs and an artificial bone scaffold was confirmed in all cases. The amount of bone formation at each case was irregular, but the results were suggested the possibility of cryopreserved MSCs on clinical use.departmental bulletin pape