The 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.

抄録全体を表示

Routine oral hygiene is important for the control of opportunistic pathogens in the oral cavity of institutionalized elderly individuals. We evaluated the effects of routine oral care on opportunistic pathogens at various time points after admission to a nursing home. Twenty-five elderly subjects living in the nursing home (mean age: 86.0±10.4 years) participated in the study. Caregivers and dental hygienists cleaned the teeth, dentures, tongue, and mucosa after each meal using both routine and professional oral care techniques. Opportunistic pathogens were collected from the teeth, tongue, and mucosal surfaces using a cotton swab; and the species of microbes were determined and the numbers were counted following cultivation on selective agar. Regular oral care including professional oral care was found to be effective for reducing infections by many kinds of opportunistic pathogens on the teeth surfaces and the oral environment without food residue during a long-term study (6 months). Further, this care after 1 month significantly reduced infections by opportunistic pathogens on mucosal surfaces in subjects without dentures; however, this was not observed in those with dentures. Our data shows the importance of regular oral care in cleaning hard and soft surfaces of the oral cavity improves the oral health of the institutionalized elderly.

抄録全体を表示

So 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.

抄録全体を表示

Objective: Phospholipase A₂ (PLA2) is a key enzyme in arachidonic acid metabolism, which is involved in the maintenance of biological homeostasis and the onset of various diseases. The immunohistochemical localization of PLA2 in the nasal mucosa has not been reported, even though the presence of messenger RNA of PLA2 has been demonstrated in the human nasal brush sample. The present study was designed to determine the localization of PLA2s in the nasal cavity. Methods: The immunohistochemichal localization of secretory PLA₂ (sPLA2) and cytosolic PLA₂ (cPLA2) in the nasal mucosa was studied using adult guinea pig. Results: Both sPLA2 and cPLA2 were localized in the nasal gland as well as the respiratory epithelium, and not in the surrounding vascular endothelial cells, olfactory gland, olfactory epithelium or submucosal tissue. Conclusion: Our data provide the first convincing evidence that both sPLA2 and cPLA2 are significantly expressed in the nasal gland and the respiratory epithelium, and are suggested to regulate the function of the nasal mucosa, such as bactericidal, Na secretion, and allergic response.

抄録全体を表示

In 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 a small 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.

抄録全体を表示

We 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.

抄録全体を表示

Purpose: Pancreatic cancer is characterized by an extremely poor prognosis due to the aggressive disease course and lack of effective therapeutic intervention. IĸB kinase (IKK), a central kinase for nuclear factor-ĸB (NF-ĸB) activation, is often constitutively activated in pancreatic cancer cells, playing a crucial role in the malignant phenotype and resistance to anti-cancer agents. This study explored how specific inhibition of IKKβ suppresses oncogenic proliferation of pancreatic cancer cells. Experimental Design: We employed two different approaches, RNA interference-mediated depletion of IKKβ (IKKβi) and use of a novel molecularly designed IKKβ inhibitor IMD-0354 to investigate the effects on the in vitro and in vivo growth and apoptotic response of pancreatic cancer cells. Results: IKKβi and IMD-0354 efficiently suppressed constitutive NF-ĸB activity and the growth of pancreatic cancer cells in monolayer and soft agar. IMD-0354 induced Annexin V expression, a typical apoptotic cell response. Notably, daily administration of IMD-0354 significantly suppressed tumor growth in NOD/SCID/γc^null (NOG) mice without any deleterious side effect. Conclusions: These results identify IKKβ as an attractive molecular target for pancreatic cancer therapy.

抄録全体を表示

The purpose of this study was to determine the effect of aging on the tactile and pain sensitivity, and the factors influencing threshold change in the oral mucosa using Semmes-Weinstein Pressure Aesthesiometer. The touch and pain thresholds of 81 healthy elderly (40 males and 41 females, 77 ± 4.5 years) were compared with those of 58 young volunteers (27 males and 31 females, 27 ± 2.5 years). We measured the pain thresholds, the touch thresholds, PCR score and amount of salivation. Semmes-Weinstein Pressure Aesthesiometer was applied to 9 points in the oral region and 4 points in the hands; the dorsum manus, the palma manus, the incisive papilla, the palatal mucosa, the buccal mucosa, the margin of the tongue, and the dorsum of the tongue. Elderly subjects showed significantly higher touch thresholds than those of young subjects in the dorsum manus, the palma manus, the buccal mucosa, the incisive papilla, the margin of the tongue, and the dorsum of the tongue (P < 0.05). The pain thresholds of elderly subjects were significantly lower than those of young subjects in the buccal mucosa and the palatal mucosa (P < 0.05). The touch threshold was not influenced by the smoking habit, denture and amount of salivation. The pain threshold was influenced by the denture on the palate.

抄録全体を表示

We 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 the defects of adult rat spinal cords, in vivo. The neurites of DRGs on HC extended linearly through the pores. HC with a 400 Òm-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.

抄録全体を表示

It has become clear that foods crushing is performed in the circumscribed region between functional cusps, that is, at “the main occluding area”. However, it is not established to evaluate this area objectively. The purpose of this study was to establish the positional evaluation of the main occluding area quantitatively and evaluate the positional change depending on the age with this method. The subjects were fifteen adults and ten adolescents who had no stomatognathic disorder. Temporary Stopping was used as test material in this study. In order to analyze the position of the main occluding area, the projected centroid coordinate of the test material was calculated and projected onto the reference axis. It was possible to quantitatively evaluate positional changes of the main occluding area depending on growth process. As a result, the main occluding areas of the adults were significantly posterior to those of the adolescents and tended to be more stable. There was a significant difference in the occlusal contant area between two groups. The occlusal contact area had great influence on the stability of the main occluding area. However, besides occlusal contact area, there might be other factors which stabilized the main occluding area.

抄録全体を表示

A porous hydroxyapatite/collagen composite (HAp/Col) was developed that consists of hydroxyapatite nanocrystals and atelocollagen. In this study, cylindrical (diameter: 5 mm, height: 3 mm) porous HAp/Col implants with different pore sizes (diameter: 160 or 290 μm) were prepared, and the influences of pore size and implanted volume were evaluated using a rabbit bone defect model. In the implant groups, one or three (diameter: 5 mm, total height: 9 mm) implants were transplanted into bone holes created in the anteromedial site of the proximal tibiae, while a group without implantation was used as a control. Histological observation revealed that at two weeks after implantation, bone formation was initiated not only from the periosteum but in regions where the implants bordered on bone marrow. At four weeks, bone formation expanded from the marrow cavity side into the center of the implants, particularly in those implants with large pores. At twelve weeks, four implant groups showed repair of cortical defects and implant absorption, which was thought to be the result of natural bone remodeling mechanisms. The control group showed bone formation developed from the periosteum without bone induction in the marrow cavity, and at four weeks, the bone hole was almost healed. pQCT analysis revealed that the expansion rates of bone tissue were higher in the large-pore implant groups than in the small-pore groups. These data demonstrate the osteoconductivity of porous HAp/Col and the importance of its porous structure.

抄録全体を表示

The meniscus is semilunar fibrocartilage, and its injury causes dysfunction of the knee. We previously reported a high chondrogenic potential of synovial mesenchymal stem cells (MSCs). Here, we examined whether intra-articular injected synovial MSCs adhered to the defect of the meniscus, survived there, and differentiated into cartilage cells. MSCs were isolated from the synovium of GFP rats. Cylindrical defects were created in the menisci in wild rats, and GFP-positive synovial MSCs were injected into the knee. In the control group, 100 μl of PBS was injected into the contralateral knee. The menisci were analyzed after day 1, weeks 2, 4, 8, and 12. One day after injecting of 10⁷ GFP-positive synovial MSCs, the meniscal defect was filled with the cells. The GFP-positive synovial MSCs expressed type II collagen, exhibited representative characteristics of chondrocytes by electron microscopy at 8 weeks, and could still be observed at 12 weeks. The histological score improved within 12 weeks but there were no statistical difference between the two groups at each period in this model. GFP mRNA expressions were not observed in distant organs at day 1. After intra-articular injection, synovial MSCs attached to the meniscal defect and differentiated into cartilage cells.

抄録全体を表示

Background: Gamma-delta (γδ) T cells regulate immune responses at mucosal surfaces. Whether they can modify allergen-induced early (EAR) and late airway responses (LAR) is unknown. Objective: We have tested the hypothesis that the γδ T cells enhance allergen-induced airway responses in mice. Methods: BALB/c wild-type (WT) mice and γδ T cell-deficient (γδ T-cell KO) mice were sensitized by intraperitoneal injection of ovalbumin (OVA) on days 1 and 15, immunized with 1% OVA aerosol on days 29-31, and challenged with 5% OVA or saline on day 33. Enhanced pause (Penh) was measured and BAL fluid was collected after challenge. Serum IgE was measured before challenge. The percentage of interleukin (IL)-4 and interferon (IFN)-γ producing T cells in splenocytes from sensitized animals was determined by flow cytometry. Results: Both EAR and LAR were observed in OVA-challenged WT mice. LAR but not EAR was inhibited in OVA-challenged γδ T-cell KO mice. γδ T-cell KO mice showed less eosinophilia in BALF and serum OVA-specific IgE. In the sensitization period, the percentage of IFN-γ producing αβ T cell in γδ T-cell KO mice was higher than that in WT mice. Conclusion: γδ T cells enhance LAR and airway inflammation but not EAR in this model of asthma.

抄録全体を表示

Neural progenitor cells (NPCs) and bone marrow stromal cells (BMSCs), both of which can differentiate into neural phenotypes, are important candidates for transplantation therapy in the central nervous system (CNS). In most cases of BMSC transplantation, functional recovery is recognized even if few transplanted cells survive in the host tissue. A reason for this may be that transplanted cells produce neurotrophic factors (NFs), which enhance neuronal survival and neurite outgrowth after CNS injury. To provide additional insight into cell therapy, we investigated the types of NFs and receptors that are expressed in NPCs and BMSCs in vitro. Both cells expressed the mRNA of nerve growth factor (NGF), cilliary neurotrophic factor (CNTF), glial cell line-derived neurotrophic factor (GDNF), and their receptors in the proliferative state. Real-time PCR analysis showed that mRNA expression of GDNF was relatively low in NPCs although its receptor was highly expressed. We thus tested if the overexpression of GDNF in NPCs affected neural differentiation without FGF-2. The overexpression of GDNF did not affect mRNA expression of β-III tubulin and neuron specific enolase (NSE), but both GDNF and GFRα1 overexpression increased the expression of neuronal markers. These results suggest that augmentation of both GDNF and GFRα1 could have positive effects during neural tissue repair.

抄録全体を表示

Occlusal stimuli and the periodontal healing of replanted teeth have been reported to be related. However, the mechanism for preventing dentoalveolar ankylosis remains unclear. Basic fibroblast growth factor (bFGF/FGF-2) is considered as a key factor in wound healing. The purpose of this study was to evaluate the relationship between occlusal stimuli, bFGF, and the periodontal healing after tooth replantation. Five-week-old male rats were divided into non-occluded, occluded, and recovery groups. The right maxillary first molars were replanted in all groups, and the left maxillary first molars in the 2-week occluded group without replantation were served as nontreated. An anterior bite plate was attached to the maxillary and mandibular incisors to produce occlusal hypofunction in the non-occluded group and was then removed after 1 week in the recovery group. Histological observations were performed after 1 and 2 weeks of the experimental period. After 2 weeks, the non-occluded group had detectable ankylosis and obvious periodontal tissue stricture. Meanwhile, the occluded and recovery groups showed enlarged and thickened periodontia without ankylosis. The number of bFGFpositive cells in the occluded and recovery groups significantly increased as compared to in the non-occluded group. These results suggest that occlusal stimuli enhance the production of bFGF in the periodontal healing of replanted teeth and prevent dentoalveolar ankylosis.

抄録全体を表示

Bone 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 cell therapies. 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.

抄録全体を表示

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease manifested clinically by progressive ataxia, parkinsonism, and autonomic dysfunction. Its cause is unknown, and there is no curative therapy. α-synuclein is an important protein forming aggregations called glial cytoplasmic inclusions (GCIs) in oligodendroglia; these aggregations are considered important in MSA pathogenesis. Overexpression of the human α-synuclein gene in mice induces the formation of GCI-like aggregations in oligodendrocytes, leading mice to exhibit neurological signs similar to those in MSA patients. However, previous studies have excluded mutations within the coding region of the α-synuclein gene in MSA patients. To determine whether alteration in the expression level of the α-synuclein gene is associated with MSA pathogenesis, we used TaqMan quantitative PCR assay to analyze the α-synuclein gene copy number in patients’ genomes. We also used quantitative RT-PCR and in situ hybridization to analyze α-synuclein mRNA expression in MSA patients’ brain tissues. We found no alteration in the α-synuclein gene copy number in the patients’ genomes (n = 50). Quantitative analysis for α-synuclein mRNA by the TaqMan method showed that α-synuclein mRNA levels were comparable between control (n = 3) and MSA (n = 3) cerebella. On in situ hybridization, the number of neurons with α-synuclein mRNA expression was no greater in the cerebella of MSA patients (n = 3) than in the controls (n = 3). However, GCIs were seen in these MSA specimens on immunohistochemistry for α-synuclein. These results suggest that α-synuclein gene expression is not the fundamental cause of MSA.

抄録全体を表示

Recently, improvement of the properties of dentin surface using dental lasers to increase bonding strength has been anticipated in the field of adhesive dentistry. The objective of this study was to investigate changes in the surface properties of human dentin after ArF excimer laser irradiation at different irradiation times, pulse repetition rates and energy densities. The SEM images of the irradiated surfaces were observed, and the contact angle and the roughness of the irradiated surface were measured. As a result, SEM demonstrated that the dentin surface became irregular following ArF excimer laser irradiation. When the energy density increased, the irregularity became more minute and dentinal tubules were more easily identified. By contrast, such changes were not observed when the irradiation time and pulse repetition rate were changed. Moreover, as energy densities increased, the contact angle tended to decrease and the surface roughness tended to increase. These results suggested that the area of the irradiated surface and wettability increased after irradiation with the ArF excimer laser. Consequently, irradiation with ArF excimer lasers could improve the surface properties and be potentially useful for adhesive dentistry.

抄録全体を表示

The objective of the study was to determine whether strenuous running exercise produces a significant amount of fibrosis in the infrapatellar fat pad (IFP) of the knee and whether intraarticular injections of hyaluronan (HA) protect fibrosis in the IFP in a rat running model. Strenuous running exercise was performed on a rodent treadmill with 5% inclination using Wistar rats. After the exercise, hyaluronan was injected into the right knee joint once per week in the HA injection group. In the treatment control group of the left knee, no injection was done. Also, the running exercise group and the sedentary control group received no HA injection. The IFP was analyzed histologically and immunohistochemically after 1 week (5 km), 2 weeks (10 km), 3 weeks (15 km) and 6 weeks (30 km). The inflammatory reaction in the IFP was not prominent at each running stage. A slightly, but significantly increased amount of inflammatory cell infiltration appeared during strenuous running. The amount of collagen fibers increased significantly at 30 km stage. Histological scores showed less fibrosis of the IFP in the HA injection group than in the control group at 30 km run. Strenuous running exercise may cause fibrosis in the IFP of runners. Intraarticular HA injection will inhibit arthrofibrosis of painful runners.

抄録全体を表示

The 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.

抄録全体を表示

Background: UDP-N-acetylglucosamine 2- epimerase/N-acetylmannosamine kinase (GNE) is a key molecule in the pathogenesis of distal myopathy with rimmed vacuoles (DMRV) and hereditary inclusion body myopathy (HIBM) and almost all such patients have some mutations in GNE. However, subcellular localization of GNE and the mechanism of muscular damage have not been clarified. Methods: A rabbit polyclonal antibody for GNE was prepared. Immunohistochemistry was performed using anti-GNE and anti-nuclear protein antibodies. Western blotting with subcellular fractionated proteins was performed to determine subcellular localization of GNE. The sizes of myonuclei were quantified in muscle biopsies from patients with DMRV and amyotrophic lateral sclerosis (ALS). Results: In DMRV muscles, immunohistochemistry identified GNE in sarcoplasm and specifically in myonuclei and rimmed vacuoles (RV). Nuclear proteins were also found in RVs. Immunohistochemistry showed colocalization of GNE and emerin in C2C12 cells. Western blotting revealed the presence of GNE in nuclear fractions of human embryonic kidney (HEK) 293T cells. The mean size of myonuclei of DMRV was significantly larger than that of ALS. Conclusion: GNE is present in myonuclei near nuclear membrane. Our results suggest that myonuclei are involved in RV formation in DMRV, and that mutant GNE in myonuclei seems to play some role in this process.

抄録全体を表示