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Get PDFHyperactivation and acrosome reaction are prerequisite steps for sperm to be able to fertilize an oocyte. In mammals, hyperactivation is defined as a movement pattern seen in spermatozoa at the site and time of fertilization. The objectives of the present experiments were to analyze the process of hyperactivation and to investigate its relationship with progesterone evoked intracellular calcium concentration ([Ca2+]i) increase and their implications with infertility. After capacitation the sperm from patients, when compared with donor's sperm, showed decreased percentage of hyperactivated sperm, molitily, progressive motility, and curvilinear velocity (VCL). On the other hand, the linearity (LIN) was increased. Amplitude of lateral head displacement (ALH) and [Ca2+]i increase (peak and plateau from baseline) showed good correlation in patients with infertility. These data suggest that impaired hyperactivation might be involved in the pathophysiology of infertility.departmental bulletin pape
Get PDFWe have studied the deposition of calcium salts in the autopsied intestines which have not been described previously as far as we were able to determine. In order to clarify the incidence, predisposing conditions, mineral compositions of the deposited materials and clinical significance of this phenomenon, we examined 76 cases of consecutive autopsied small intestines by von Kossa's staining. Deposited calcium salts were further examined by electron microscopically, energy-dispersive X-ray spectroscope and electron diffraction analysis. Deposition of calcium salts was observed in the small intestines of 13 cases. Among them, 10 cases were accompanied by hypercalcemia. Deposition of calcium salts was mainly observed in smooth muscle cells of the proper muscle layers and ganglion cells of the Auerbach's myenteric plexus. Intestinal calcinosis was frequently accompanied by deposition of calcium salts in the proper muscle layers of esophagus and large intestine, renal tubules and cardiac myocardial cells. Electron microscopically, the calcium salts were identified as needle-shaped crystals and located on the surface of the extracellular-collagen bundles, in the cytoplasm, mitochondria and nucleus of the smooth muscles cells. Energy-dispersive X-ray spectroscope and electron diffraction analysis suggested the deposited calcium salts as hydroxyapatite. Two patients among the six cases with moderate to severe calcium deposition showed clinical manifestation of paralytic ileus. In conclusion, intestinal calcinosis was frequently observed mostly associated with hypercalcemia. Calcium salts of hydroxyapatite were deposited to the smooth muscle cells and the Auerbach's myenteric plexus of the muscular layer. Deposition of calcium salts might occasionally causes the paralytic ileus but clinical significance of this lesion requires further examination.departmental bulletin pape
Get PDFPurpose: The aim of our study was to explore the effects of different loading positions on the movements of the abutment tooth and denture base of removable partial denture with unilaterally designed framework (RPD-U). Materials and Methods: The experiment was carried out with a simulation model of a mandible without left molars. The movements of abutment tooth and denture base of the unilateral and bilateral designs were due to 30N vertical load on 12 loading positions determined with a strain gauge circuitry. The effects of loading positions on the movements of the abutment tooth and denture base were compared between two designs. Results: During the loading on buccal, lingual positions, and the most disto-central position the movements of the abutment tooth and denture base of the unilateral design were significantly greater than those of the bilateral design (P<0.01). During the loading on the three mesio-central positions the movements of the abutment tooth and denture base were equal between designs, and were significantly lower than during the loading on the other positions (P<0.01). Conclusion: Ending the denture teeth at the mesial cusp of second molar and positioning the occlusal contacts over the ridge crest adequately stabilize the abutment tooth and denture base of RPD-U.departmental bulletin pape
Get PDFBone-tendon-bone (B-T-B) type grafts were prepared for ligament reconstruction by harvesting the radius from rats, wrapping both ends of each bone with a laboratory film leaving only the central 10 mm exposed, and demineralizing the central part by immersing the bone in 1.75% HCl solution. In the grafts prepared, the central part of the bone became semi-translucent and flexible while the ends remained as hard bone tissue, thus forming a B-T-B type graft. The tensile strength of the grafts was greater than that of the medial collateral ligaments of the rats and about the same as of their anterior cruciate ligaments. No inflammation or other adverse reaction was noticed in experimental subcutaneous transplantation and the grafts showed excellent biocompatibility. In experimental ligament reconstruction, the test animals did not show any impairment on gait. There was invasion of fibroblasts into the graft at 4 weeks, and the fibroblasts were found through the whole graft and what looked like ligament tissue could be seen macroscopicaly at 8 weeks. Besides, bone tissue had infiltrated into the inside cavity of the non-demineralized part of the graft and proliferation, resulting in good bone union. The results obtained suggest that the grafts prepared in this study have a sufficient potential as B-T-B type grafts for ligament reconstructiondepartmental bulletin pape
Get PDFThe aim of this study was to clarify the relationship between partially edentulous pattern and the masticatory function in removable partial denture wearers. Eighty eight removable partial denture wearers and 7 subjects with intact dentition volunteered for this study. Using the Eichner's index, all subjects were divided into 6 groups. Electromyographic (EMG) activities of the masticatory muscle were recorded during chewing a piece of raw carrot. The masticatory function was analyzed by using the variation coefficient (VC) of the time parameter of EMG interval recorded during mastication. The association of the VC with group classification based on Eichner's index was analyzed using analysis of covariance with gender and age as the covariates. The result of the analysis revealed that the VC was significantly associated with group classification and the patients in groups without posterior occlusal supports exhibited significantly higher VC values than those in groups with posterior occlusal supports. These findings suggested that the reduced function in patients without the posterior occlusal contacts was difficult to attain improved and satisfactory outcome with removable partial dentures and that there is a significant need for posterior occlusal support for the preservation of masticatory function.departmental bulletin pape
Get PDFThe exact etiology of schizophrenia remains undetermined but accumulating evidence suggests that disturbances in neurodevelopment may represent one contributory factor. Netrin G1, a recently cloned gene from the mouse, has been shown to play a potential role in the formation of neural circuitry. To determine whether this gene is involved in the development of psychosis, we performed a genetic association study of human netrin G1 gene in schizophrenia. First, we determined the human genomic structure of netrin G1 by direct comparisons between cDNA and genome sequences, and by database searches. For the subsequent examination of heterozygosity, we selected 10 single nucleotide polymorphisms (SNPs) for an association test in case (n = 180) and control (n = 180) samples. Among these SNPs, IVS8-1467C>T showed significant allelic association (nominal P = 0.020) with disease. This SNP is located in a haplotype block of ~40 kb and haplotypes in this block also displayed significant association (most significant P = 0.017). These findings suggest that netrin G1 or a nearby gene may contribute to the overall genetic risk for schizophrenia.departmental bulletin pape
Get PDFBackground: Expanding cells ex vivo is an important step in tissue engineering and the culture medium is usually supplemented with bovine serum. When a patient receives bone marrow stromal cells (BMSCs) grown in a medium containing bovine serum, infection of bovine diseases and/or the patient's unfavorable immune reaction to bovine proteins are of concern. To overcome these problems, we examined whether a patient's autologous serum could support the growth and differentiation of his/her BMSCs. Methods: Bone marrow was collected from the iliac by aspiration and cultured in a medium supplemented with 10% autologous serum or 10% fetal bovine serum (FBS). Number and area of the colonies of fibroblast-like cells (colony-forming unit fibroblast, CFU-f) were measured 8 days after the cell inoculation (day 8). Number and area of the alkaline phosphatase (ALP) positive colonies were measured on day 10. On day 40, the cultures were stained with alizarin red S. RNA was prepared from the culture on day 20, and the mRNA expression of osteoblastic genes was examined by reverse transcription polymerase chain reaction(RT-PCR) analysis. Results: BMSCs, which were cultured in the medium supplemented with autologous serum, produced CFU-f, ALP-positive area and mineralized nodules, which is comparable to the BMSCs in the culture supplemented with FBS. The mRNA expressions of osteopontin, parathyroid hormone receptor, osteocalcin, and bone sialoprotein were detected in the culture supplemented with autologous serum. Conclusions: A patient's autologous serum could expand BMSCs without losing their potentiality for osteoblastic differentiation. Patients' autologous serum could be efficient to expand BMSCs and to be utilized safely for bone regeneration therapy.departmental bulletin pape
Get PDFEndochondral bone formation observed at the mandibular condyle is regulated by various growth factors including insulin-like growth factor-I (IGF-I). In this paper, we describe a method for the local administration of IGF-I to the bilateral mandibular articular cavities of 3- and 12-week-old rats, and the effects of IGF-I on endochondral bone formation by histomorphometric techniques. In 3-week-old IGF-I-treated rats, three days after administration, an increase in bone tissue was found in the area of the subchondral cancellous bone layer. In 12-week-old IGF-I-treated rats, three days after administration, an increase in the thickness of the condylar cartilage and a decrease in bone tissue were observed in the area of the subchondral cancellous bone layer. This study revealed that the local administration of IGF-I on mandibular condyle caused different histological changes between growth and maturation periods. These results indicated that the effects of IGF-I on endochondral bone formation in the mandibular condyle were age-dependent.departmental bulletin pape
Get PDFIn order to investigate the morphological characteristics of Japanese patients with obstructive sleep apnea (OSA) and basis for selection of an oral appliance (OA) therapy, the craniofacial skeleton, soft tissue and upper airway were analyzed on lateral cephalograms from 103 patients with OSA and 98 control subjects. At first, the 103 OSA patients were divided into two groups according to their body mass index (BMI). The results were the following: Micrognathia was a major risk factor of Japanese OSA patients instead of obesity; the narrowing in the hypopharynx was observed due to the inferiorlocated hyoid bone, especially in the obese group, an enlarged tongue and sticking of fatty-tissue to upper airway wall were observed in addition. Secondly, the 103 OSA patients were treated by OA, and were classified according to the reduction ratio of AHI (rAHI) again. The results suggested that the patients group which showed rAHI ≧50 % had a balanced relationship between the maxilla and mandible. These findings proved that the morphological characteristics specific to Japanese patients with OSA and patients who were allowed to accept the OA therapy were exist.departmental bulletin pape
Get PDFIn chemo-mechanical caries removal procedures, chloramines are typically used for chemical softening of carious dentin. However, the specific effect of chloramines to be compared to sodium hypochlorite has not been sufficiently clarified. In present study, the effect of chloramines used in the Carisolv-system on carious dentin mechanical properties and morphology were investigated, using Vickers hardness test and scanning electron microscopy (SEM). Sections of permanent teeth with dentin caries were treated with chloramines, prepared by mixing amino acids (glutamic acid, lysine, and leucine) with sodium hypochlorite or with sodium hypochlorite alone or with purified water. There was a tendency that the application of the sodium hypochlorite solution softened the sound dentin and/or inner layer of carious dentin more than the application of the chloramines solution did. In SEM observations, the application of chloramines resulted in opening dentinal tubules in the outer layer of carious dentin: Occluded dentinal tubules were seen after sodium hypochlorite application. There is a possibility that the amino acids in the Carisolv-system decrease the aggressive effect of sodium hypochlorite on sound dentin and/or inner layer of carious dentin and also would enhance the disrupting effect on degenerated collagen in carious dentin outer layer.departmental bulletin pape