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Yamamoto M, Pohli S, Durany N, Ozawa H, Saito T, Boissl KW, Zöchling R, Riederer P, Böning J, Götz ME. Increased levels of calcium-sensitive adenylyl cyclase subtypes in the limbic system of alcoholics: evidence for a specific role of cAMP signaling in the human addictive brain. Brain Res 2001; 895:233-7. [PMID: 11259782 DOI: 10.1016/s0006-8993(00)03260-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We examined the amounts of several adenylyl cyclase (AC) isoforms and of cAMP-response element binding protein (CREB) in alcoholic and control brains. Immunoreactivity of type I AC was significantly increased in alcoholic nucleus accumbens and corpus amygdaloideum. Immunoreactivity of type VIII AC was also increased in alcoholic corpus amygdaloideum and hippocampus. CREB immunoreactivities were unchanged. These findings indicate that the brain-region specific increase of Ca(2+)-sensitive AC may contribute to the pathophysiology of alcoholism.
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Abstract
Melorheostotic bone was examined histopathologically. In the severely affected areas, an abundance of osteoid and increased angiogenesis was observed. Increased osteoid without mineralization indicated the overproduction of bone matrix. Bone resorption also appeared to increase because osteoclasts were numerous in melorheostotic bone, thus suggesting a high rate of bone turnover. In addition, transforming growth factor-beta was immunolocalized in the periosteal fibroblasts, mesenchymal cells surrounding vessels, endothelial cells, and osteoblasts, while basic fibroblast growth factor was found in endothelial cells and mast cells near vessels. These cytokines may have some association with the exuberant bone matrix production and angiogenesis in melorheostosis.
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103
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Hoshi K, Ejiri S, Ozawa H. Localizational alterations of calcium, phosphorus, and calcification-related organics such as proteoglycans and alkaline phosphatase during bone calcification. J Bone Miner Res 2001; 16:289-98. [PMID: 11204429 DOI: 10.1359/jbmr.2001.16.2.289] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
To further approach the mechanisms of bone calcification, embryonic rat calvariae were observed at electron microscopic level by the means of fine structures and various cytochemical localizations, including nonspecific proteoglycan (PG) stained by cuprolinic blue (CB), decorin, chondroitin sulfate, hyaluronan, and alkaline phosphatase (ALP), as well as the elemental mapping of calcium (Ca) and phosphorus (P) by energy-filtering transmission electron microscopy (EFTEM). In the calvariae, calcification advanced as the distance from osteoblasts increased. Closer to the osteoblasts, the osteoid was marked by an abundance of CB-positive PGs around collagen fibrils. After crystallization within matrix vesicles, calcified nodules formed and expanded, creating a coherent calcified matrix. The sizes of CB-positive PG-like structures diminished as calcification proceeded. Although small CB-positive structures were accumulated in early stage-calcified nodules, they were localized along the periphery of larger calcified nodules. Cytochemical tests for decorin, chondroitin sulfate, and hyaluronan determined their presence in the areas around collagen fibrils of the osteoid, as well as in and around calcified nodules, whereas ALP was found in the matrix vesicles, as well as in and around the calcified nodules. Ca tended to localize at the PG sites, while P often mapped to the collagen fibril structures, in the uncalcified matrix. In contrast, Ca/P colocalization was visible in and around the calcified nodules, where ALP and smaller CB-positive structures were observed. The difference in the localization patterns of Ca and P in uncalcified areas may limit the local [Ca2+][PO4(3-)] product, leading to the general inhibition of hydroxyapatite crystallization. The downsizing of CB-positive structures suggested enzymatic fragmentation of PGs. Such structural alterations would contribute to the preservation and transport of calcium. ALP possesses the ability to boost local phosphate anion concentration. Therefore, structurally altered PGs and ALP may cooperate in Ca/P colocalization, thus promoting bone calcification.
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Abstract
Crystals in bones are enveloped within organic crystal sheaths of 5-10 nm widths. In order to analyse their components, we investigated the immunolocalizations of chondroitin 4- and 6-sulphate, keratan sulphate, bone sialoprotein and osteopontin. All of these, except chondroitin 6-sulphate, were found in bone matrix. Although the localizations of chondroitin 4-sulphate and keratan sulphate tended to focus within calcified nodules, bone sialoprotein and osteopontin were widely distributed in the area, being linearly arranged along electron-dense structures corresponding to crystal sheaths. These two proteins possess the ability to affect nucleation or elongation of hydroxyapatite, positively or negatively, in vitro. Our results suggested that bone sialoprotein and osteopontin may combine to form the crystal sheaths which are thought to control crystal formation and growth, using the seemingly opposite functions of bone sialoprotein and osteopontin.
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105
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Hoshi K, Ejiri S, Probst W, Seybold V, Kamino T, Yaguchi T, Yamahira N, Ozawa H. Observation of human dentine by focused ion beam and energy-filtering transmission electron microscopy. J Microsc 2001; 201:44-9. [PMID: 11136438 DOI: 10.1046/j.1365-2818.2001.00784.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Molar dentine was sliced into 100 nm ultrathin sections, by means of a focused ion beam, for observation by energy-filtering transmission electron microscopy (EFTEM). Within the matrix, crystals approximately 10 nm wide and 50-100 nm long were clearly observed. When carbon and calcium were mapped in electron spectroscopic images by EFTEM, carbon failed to localize in crystals. However, it was found in other regions, especially those adjacent to crystals. Because carbon localizations were thought to reflect the presence of organic components, carbon concentration in regions near crystals suggested the interaction of crystals and organics, leading to organic control of apatite formation and growth. Ca was present in almost all regions. The majority of Ca localizing in regions other than crystals may be bound to organic substances present in dentine matrix. These substances are thought to both accumulate Ca and act as reservoirs for crystallization of apatite in dentine.
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106
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Yamamoto M, Pohli S, Durany N, Ozawa H, Saito T, Boissl KW, Zöchling R, Riederer P, Böning J, Götz ME. Immunoreactivity of cAMP response element binding protein is not altered in the post-mortem cerebral cortex or cerebellum of alcoholics. Alcohol Alcohol 2001; 36:70-4. [PMID: 11139419 DOI: 10.1093/alcalc/36.1.70] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We examined amounts of cAMP response element binding protein (CREB) and its phosphorylated form in post-mortem frontal and temporal cortices and cerebella from alcoholics and controls by immunoblotting. No significant differences were observed in the levels of these proteins in each brain region, suggesting that the assumed neuroadaptations to chronic ethanol intake may not be reflected by quantitative alterations of CREB in alcoholic brain.
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107
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Kondo Y, Irie K, Ikegame M, Ejiri S, Hanada K, Ozawa H. Role of stromal cells in osteoclast differentiation in bone marrow. J Bone Miner Metab 2001; 19:352-8. [PMID: 11685650 DOI: 10.1007/s007740170004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2001] [Accepted: 06/04/2001] [Indexed: 10/27/2022]
Abstract
Bone marrow stromal cells have been considered to play an important role in osteoclast differentiation. However, the interaction of these cells in vivo has not been clearly demonstrated. To clarify this, we examined the distribution of alkaline phosphatase (ALPase) and tartrate-resistant acid phosphatase (TRAPase) activities as markers of osteoblastic and osteoclastic cells, respectively. Rat tibiae were fixed and embedded in Technovit 8100 or paraffin. ALPase and TRAPase activities were detected simultaneously on a plastic section by the azo-dye method. ALPase activity was detected on the plasma membranes of osteoblasts and some bone marrow fibroblastic stromal cells. These ALPase-positive cells were connected to each other by cytoplasmic processes, forming a cellular network in bone marrow. The ALPase activity of fibroblastic stromal cells tended to be stronger in those cells close to the bone surface than in the cells in the center of bone marrow. Reticular fibers in bone marrow were found to form a network. The ALPase-positive fibroblastic stromal cells may be reticular cells, because the localization of those cells was in accord with the localization of reticular fibers. The TRAPase-positive mononuclear cells and osteoclasts were mostly observed to be associated with the intensely ALPase-positive fibroblastic stromal cells. Immunoreactivity of osteoclast differentiation factor (ODF) was found in the fibroblastic stromal cells. These findings suggest that the network of ALPase-positive fibroblastic stromal cells in bone marrow serves as a guide for the migration of osteoclast precursor cells toward the bone surface, and may control the differentiation and activity of osteoclasts.
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108
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Nishino I, Amizuka N, Ozawa H. Histochemical examination of osteoblastic activity in op/op mice with or without injection of recombinant M-CSF. J Bone Miner Metab 2001; 19:267-76. [PMID: 11498728 DOI: 10.1007/s007740170010] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2001] [Accepted: 04/09/2001] [Indexed: 11/29/2022]
Abstract
Osteopetrotic (op/op) mice do not exhibit bone remodeling because of defective osteoclast formation caused by the depletion of macrophage colony-stimulating factor (M-CSF). In the present study, we investigated tibial bones of op/op mice with or without prior injections of M-CSF to determine whether osteoclast formation and subsequent bone resorption could activate osteoblasts, which is known as a "coupling" phenomenon. In op/op mice, no osteoclasts were present, but the metaphyseal osteoblasts adjacent to the growth plate cartilage seemed to be active, revealing an intense alkaline phosphatase (ALPase) immunoreactivity. Consequently, primary trabecular bones were extended continuously to the diaphysis, indicating that bone modeling is well achieved in op/op mice. In contrast with the metaphysis, most of the diaphyseal osteoblasts were flattened and showed weak ALPase activity, and, as a result, they seemed to be less active. Osteopontin (OPN) was localized slightly at the interface between bone and cartilage matrices of the primary trabeculae. In contrast, in op/op mice injected with M-CSF, tartrate-resistant acid phosphatase-positive osteoclasts appeared, resorbing trabecular bones of the diaphyseal region. The diaphyseal osteoblasts in the vicinity of the active osteoclasts were cuboidal and exhibited strong ALPase immunoreactivity. OPN was observed not only at the bone-cartilage interface, but also significantly on the resorption lacunae beneath the bone-resorbing osteoclasts. These observations indicate that the activation of diaphyseal osteoblasts appears to be coupled with osteoclast formation and subsequent osteoclastic bone resorption. Alternatively, the metaphyseal osteoblasts at the chondro-osseous junction seemed to be less affected by osteoclastic activity.
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Ikehata H, Aiba S, Ozawa H, Ono T. Thermolysin improves mutation analysis in skin epidermis from ultraviolet light-irradiated Muta Mouse. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2001; 38:55-58. [PMID: 11473388 DOI: 10.1002/em.1050] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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110
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Ikegame M, Ishibashi O, Yoshizawa T, Shimomura J, Komori T, Ozawa H, Kawashima H. Tensile stress induces bone morphogenetic protein 4 in preosteoblastic and fibroblastic cells, which later differentiate into osteoblasts leading to osteogenesis in the mouse calvariae in organ culture. J Bone Miner Res 2001; 16:24-32. [PMID: 11149486 DOI: 10.1359/jbmr.2001.16.1.24] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Mechanical stress is an important factor controlling bone remodeling, which maintains proper bone morphology and functions. However, the mechanism by which mechanical stress is transduced into biological stimuli remains unclear. Therefore, the purpose of this study is to examine how gene expression changes with osteoblast differentiation and which cells differentiate into osteoblasts. Tensile stress was applied to the cranial suture of neonatal mouse calvaria in a culture by means of helical springs. The suture was extended gradually, displaying a marked increase in cell number including osteoblasts. A histochemical study showed that this osteoblast differentiation began in the neighborhood of the existing osteoblasts, which can be seen by 3 h. The site of osteoblast differentiation moved with time toward the center of the suture, which resulted in an extension of osteoid. Scattered areas of the extended osteoid were calcified by 48 h. Reverse-transcription polymerase chain reaction (RT-PCR) revealed that tensile stress increased bone morphogenetic protein 4 (BMP-4) gene expression by 6 h and it remained elevated thereafter. This was caused by the induction of the gene in preosteoblastic cells in the neighborhood of osteoblasts and adjacent spindle-shaped fibroblastic cells. These changes were evident as early as 3 h and continued moving toward the center of the suture. The expression of Cbfa1/Osf-2, an osteoblast-specific transcription factor, followed that of BMP-4 and those cells positive with these genes appeared to differentiate into osteoblasts. These results suggest that BMP-4 may play a pivotal role by acting as an autocrine and a paracrine factor for recruiting osteoblasts in tensile stress-induced osteogenesis.
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111
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Ikebe T, Ozawa H, Lida M, Shimamoto T, Handa K, Komachi Y. Long-term prognosis after stroke: a community-based study in Japan. J Epidemiol 2001; 11:8-15. [PMID: 11253911 DOI: 10.2188/jea.11.8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Stroke is the leading cause of severe disability in the elderly. Under the national insurance for care and assistance for the elderly starting in 2000, data must be obtained on the prognostic status of stroke patients in communities. We identified 322 incident strokes in six communities (total census population=71,610) during the two- or three-years survey period between 1987 and 1990, and we completed a follow-up of the respective prognoses of most of these patients at one, three, and five years after the onset (n=315 stroke patients) (98%). One year after stroke, 33% of the 315 strokes were dead, 13% were dependent, and 54% were independent. After three years, 44% were dead, 13% were dependent, and 43% were independent. After five years, 52% were dead, 9% were dependent, and 39% were independent. The long-term prognosis was poorer with increased age, and poorer for women than for men except in the case of men ages less than 55 years old at onset. Among patients who were dependents, the proportion of taken care at home was approximately 30% one year after onset, and 50% three to five years after onset. It is estimated that approximately 17 dependents from 127 incident strokes in a population of around 70,000 every year. Because the average survival time of dependents was about 4 years, the prevalence of dependents is estimated to be 68, indicating that the prevalence is about 10 persons per 10,000. Over the period of this study, and as compared with the reported proportions in community-based studies in the 1970's, the proportion of deaths declined and that of independents increased, probably due to reduced severity of stroke. However, the proportion of dependents did not change significantly over time. Thus, under the terms of the new national insurance, it is essential for family and communities to cooperate in taking care of dependent stroke patients.
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112
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Ding YY, Ozawa H, Yokoyama T, Nasu Y, Chancellor MB, Kumon H. Reliability of color Doppler ultrasound urodynamics in the evaluation of bladder outlet obstruction. Urology 2000; 56:967-71. [PMID: 11113742 DOI: 10.1016/s0090-4295(00)00804-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVES To analyze the intrarater and interrater reliability of a newly developed noninvasive urodynamic technique based on color Doppler ultrasound for the evaluation of bladder outlet obstruction. We previously demonstrated the feasibility of this new technique. METHODS Color Doppler ultrasound urodynamic evaluations were performed on 31 men with and without bladder outlet obstruction. An ultrasound image-directed Doppler system with a 3.75-MHz probe operated by a remote control robotic manipulator was used to obtain color scale data using the transperineal approach in men during voiding. We measured the flow velocities in the distal prostatic (V1) and membranous urethra (V2) and used them to obtain the velocity ratio (VR = V1/V2). Combining this information with simultaneous uroflowmetry, the functional cross-sectional area of the distal prostatic urethra (A1) was calculated. These parameters were independently reinterpreted by an inexperienced investigator using the color image data stored in a personal computer. The intrarater and interrater reliability for VR were assessed using a classification based on cutoff values previously shown to indicate the presence or absence of obstruction. RESULTS The retest correlation using Spearman's rho for VR in terms of intrarater and interrater reliability was 0.95 and 0.57, respectively; that for A1 was 0.97 and 0.64, respectively. Using a VR of less than 1.1 (to indicate the absence of obstruction) and a VR greater than 1.6 (to indicate the presence of obstruction) for classification, intrarater and interrater agreement occurred in 93.6% to 96.8% and 77.4% to 83. 9% of cases, respectively. CONCLUSIONS The color Doppler ultrasound urodynamic technique for noninvasive evaluation of bladder outlet obstruction can be performed with reasonable reliability.
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113
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Yamamoto M, Götz ME, Ozawa H, Luckhaus C, Saito T, Rösler M, Riederer P. Hippocampal level of neural specific adenylyl cyclase type I is decreased in Alzheimer's disease. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1535:60-8. [PMID: 11113632 DOI: 10.1016/s0925-4439(00)00083-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Previous studies reported disruption of adenylyl cyclase (AC)-cyclic AMP (cAMP) signal transduction in brain of Alzheimer's disease (AD). We also demonstrated that basal and stimulated AC activities in the presence of calcium and calmodulin (Ca(2+)/CaM) were significantly decreased in AD parietal cortex. In the present study, we examined the amounts of Ca(2+)/CaM-sensitive types I and VIII AC, and Ca(2+)/CaM-insensitive type VII AC in the postmortem hippocampi from AD patients and age-matched controls using immunoblotting. The specificities of the anti-type VII and VIII AC antibodies were confirmed by preabsorption with their specific blocking peptides. We observed a significant decrease in the level of type I AC and a tendency to decrease in the level of type VIII AC in AD hippocampus. On the other hand, the level of type VII AC showed no alteration between AD and controls. A body of evidence from the studies with invertebrates and vertebrates suggests that types I and VIII AC may play an essential role in learning and memory. Our finding thus firstly demonstrated that a specific disruption of the Ca(2+)/CaM-sensitive AC isoforms is likely involved in the pathophysiology in AD hippocampus.
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114
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Iwata H, Ozawa H, Kamei A, Sasaki M, Hanaoka S, Sugai K, Hashimoto T, Nonaka I. Siblings of Schwartz-Jampel syndrome with abnormal muscle computed tomographic findings. Brain Dev 2000; 22:494-7. [PMID: 11111063 DOI: 10.1016/s0387-7604(00)00184-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Schwartz-Jampel syndrome (SJS) is a disorder characterized by myotonia, joint contractures, skeletal abnormalities, facial dysmorphism and growth retardation. We present two boys of ages 4 and 8 years with SJS. Their clinical, electromyographic and histopathological findings were similar to those described, except for computed tomography (CT) images that revealed diffuse high attenuation in sternocleidomastoid muscles and low attenuation in the paraspinal, quadriceps, sartorius, soleus and gastrocnemius muscles. This is the first report describing abnormal muscle CT findings associated with SJS. Additional studies of muscle CT might help to improve understanding of the pathogenesis of SJS.
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115
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Yamada M, Yamada M, Yamazaki S, Takahashi K, Nishioka G, Kudo K, Ozawa H, Yamada S, Kiuchi Y, Kamijima K, Higuchi T, Momose K. Identification of a novel gene with RING-H2 finger motif induced after chronic antidepressant treatment in rat brain. Biochem Biophys Res Commun 2000; 278:150-7. [PMID: 11071867 DOI: 10.1006/bbrc.2000.3773] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previously, we have identified 200 cDNA fragments as antidepressant related genes/ESTs. In this study, using these cDNAs, we developed our original cDNA microarray for rapid secondary screening of candidate genes as the novel therapeutic targets. With this microarray, we found that the expression of a novel gene, ADRG34, was significantly increased in rat hippocampus which had been chronically treated with a selective serotonin reuptake inhibitor antidepressant, sertraline. RT-PCR analysis also demonstrated the induction of ADRG34 at mRNA levels in rat hippocampus and the frontal cortex. This cDNA encoded 685 amino acid residues containing a RING-H2 finger motif at the carboxy-terminal. Sequence analysis of ADRG34 with the EMBL/GenBank database showed significant homology to mouse and human kf-1 gene. Our data suggest that ADRG34, a possible rat homologue of kf-1, may be one of the common functional molecules induced after chronic antidepressant treatment.
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116
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Ozawa H, Noma S, Nonaka I. [Myositis and rhabdomyolysis with influenza infection]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 2000; 58:2276-81. [PMID: 11225317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Myositis and rhabdomyolysis with influenza are rare, but sometimes serious complications. Patients with myositis more commonly have influenza B infection than influenza A. On the other hand, rhabdomyolysis are more frequently recognized in patients with influenza A infection than those with influenza B. Upper respiratory symptoms usually precede myositis, while rhabdomyolysis occurs simultaneously or shortly after the respiratory symptoms. Creatine kinase levels are elevated in myositis mildly and in rhabdomyolysis markedly. Influenza myositis improve spontaneously within 6 weeks, but influenza rhabdomyolysis sometimes induce renal failure with fatal outcome. Although the true incidence of myositis and rhabdomyolysis in the influenza infection remains unknown, careful medical care is necessary when patients have muscle pain and weakness.
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117
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Tanaka M, Ejiri S, Kohno S, Ozawa H. Region-specific bone mass changes in rat mandibular condyle following ovariectomy. J Dent Res 2000; 79:1907-13. [PMID: 11145364 DOI: 10.1177/00220345000790111601] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The effects of estrogen deficiency on the mandible have been indicated; however, there have been only a few reports on the mandibular condyle. To clarify the region-specific changes of condyles following estrogen deficiency, we histomorphometrically studied the anterior and posterior regions of condyles in sham-operated (Sham) and ovariectomized (Ovx) female Fischer rats, since it has been reported that rat occlusal force loads mainly onto the anterior part of the condyle. The anterior and posterior regions of condyles showed significantly different bone dynamics. The bone volume in the anterior region of the Sham group increased to 79.9% with aging, but that of the posterior region remained at ca. 60%. In the Ovx group, the bone volume of the posterior region significantly declined to 42.7% until 60 days post-ovariectomy, although no changes occurred in the anterior region. As compared with the Sham counterparts, both regions of the Ovx group showed high bone turnover and revealed significantly low bone volume at 60 days (p < 0.01). Regional differences between anterior and posterior regions were more emphasized in the Ovx than in the Sham group. The osteoclast number and amount of eroded surface in the Ovx were higher in the posterior than in the anterior region, with significance at 30 and/or 60 days (p < 0.05). The mineralized surface at 14 days and the bone formation rate at 60 days in the Ovx posterior region were significantly lower than those in the Ovx anterior region (p < 0.05). Consequently, a net bone loss occurred in the posterior region of the mandibular condyle in ovariectomized rats, owing to region specificity and estrogen deficiency.
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118
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Hoshi K, Ejiri S, Ozawa H. Ultrastructural, cytochemical, and biophysical aspects of mechanisms of bone matrix calcification. KAIBOGAKU ZASSHI. JOURNAL OF ANATOMY 2000; 75:457-65. [PMID: 11155693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
Primary calcification in embryonic ossification occurs as follows: crystallization within matrix vesicles, formation of calcified nodules, and finally the establishment of expansive calcified matrix. However, the participation of the matrix vesicles in other types of bone calcification, such as bone formation during bone remodeling in adults has not been examined sufficiently. We introduce our recent observations on the presence of matrix vesicles in aged bones. In addition, although it is well known that the extracellular fluid supersaturates the calcification crystal, hydroxyapatite, the specific mechanisms by which bone matrix calcify remain unclear. In order to further approach the mechanisms of bone matrix calcification, we also review ultrastructural and localizational alterations of the matrix organics according to the progression of calcification, and an evaluation of mineral micro-environment in the calcifying sites by energy-filter transmission electron microscopy.
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119
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Saito I, Folsom AR, Aono H, Ozawa H, Ikebe T, Yamashita T. Comparison of fatal coronary heart disease occurrence based on population surveys in Japan and the USA. Int J Epidemiol 2000; 29:837-44. [PMID: 11034966 DOI: 10.1093/ije/29.5.837] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Although vital statistics have indicated large Japanese-American differences in mortality rates for coronary heart disease (CHD), the magnitude of difference has not been documented well using comparable validation of cause of death. METHODS Population-based fatal CHD data were compared between the Oita Cardiac Death Survey, Japan and the Atherosclerosis Risk in Communities (ARIC) Study, USA. Both studies (population: Oita City 198 093; the ARIC comunities 286 820) identified possible fatal CHD events (International Classification of Diseases, Ninth Revision [ICD-9]: 410-414, 250, 401-402, 427-429, 440, and 798-799) among residents aged 35-74 years during 1992-1993. Comparable criteria for classifying cause of death were applied. Sex-specific, age-adjusted mortality rates of CHD were calculated by place of death. RESULTS In all, 330 deaths in Oita and 1398 in the ARIC communities had eligible ICD-9 death certificate codes; CHD codes (ICD-9 410-414) comprised 30.6% of investigated deaths in Oita and 58.6% in ARIC. For men, the non-validated rate ratio for CHD deaths (ARIC:Oita City) was 5.9 (95% CI : 4.2-8.5), which fell to 4.7 (95% CI : 3.5-6.4) with validation and inclusion of sudden deaths within one hour of onset as fatal CHD. For women, the overall non-validated rate ratio was 4.6 (95% CI : 2.8-7.6), which fell to 3.9 (95% CI : 2.4-6.3) with validation and but there was little further change when the sudden deaths were added. CONCLUSIONS Our results suggest that differences in fatal CHD rates between Japanese and Americans were not as large as suggested by vital statistics when events were validated and sudden deaths were included.
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Yang Y, Ozawa H, Yuri K, Kawata M. Postnatal development of NADPH-diaphorase activity in the rat: the role of nitric oxide in the ontogeny of arginine vasopression and oxytocin. Endocr J 2000; 47:601-13. [PMID: 11200942 DOI: 10.1507/endocrj.47.601] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
To clarify the role of nitric oxide (NO) in the ontogeny of arginine vasopressin (AVP) and oxytocin (OXT) neurons in the hypothalamo-neurohypophysial system (HNS), we observed the coexpression pattern of NADPH-diaphorase (NADPH-d) activity and AVP- or OXT-immunoreactivity (IR) in the rat hypothalamus and posterior pituitary during the postnatal period. The enzymatic activity of NADPH-d was observed in the supraoptic nucleus (SON), paraventricular nucleus (PVN), median eminence (ME) and posterior pituitary throughout the postnatal development. AVP-containing neurons were clearly observed from postnatal day 1 in both the SON and PVN, while OXT-containing neurons were recognized from postnatal day 14. The coexistence of NADPH-d and AVP or OXT was detected in the SON from postnatal day 14. At postnatal day 21, the coexpression pattern was approximately the same as that of the SON and PVN in adult rats. Our findings indicated that the expression of NADPH-d and OXT was observed from almost the same postnatal period in both the SON and PVN. In addition, the pattern of increased numbers of NADPH-d positive fibers was similar to that of OXT-immunoreactive fibers in both the inner layer of the ME and the posterior pituitary. A good correlation was thus obtained between OXT expression and NADPH-d activity in the HNS during postnatal development. The present study suggests that NO is more closely involved in the expression and regulation of secretion of OXT than AVP.
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Amizuka N, Ozawa H, Sasaki T. The biological action of parathyroid hormone-related peptide (PTHrP) and fibroblast growth factor receptor 3 (FGFR3) on bone and cartilage. KAIBOGAKU ZASSHI. JOURNAL OF ANATOMY 2000; 75:415-25. [PMID: 11155687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Parathyroid hormone (PTH)-related peptide (PTHrP) was determined to be a factor inducing malignancy-associated hypercalcemia by activating a common receptor (PTH/PTHrP receptor) with PTH. PTHrP gene "knock out" mice showed a form of dyschondroplasia due to reduced proliferation of chondrocytes. In addition, heterogenous populations of variously-differentiated chondrocytes were present in the hypertrophic zone of the mutant epiphyseal plate. Although the homozygotes die within several hours after birth, the adult mice, heterozygous for PTHrP gene deletion, showed a delayed skeletal abnormality at 3 month old, with a reduced amount of PTHrP transcript, therefore, PTHrP appears to modulate cell proliferation and differentiation at both fetal and adult stages. The co-localization of PTHrP and its receptor in osteoblastic cells and chondrocytes suggested a paracrine/autocine mode of action manner of these molecules. Recently, fibroblast growth factor receptor 3 (FGFR3) deficient mice demonstrated skeletal defects including kyphosis, scoliosis, crooked tails and curvature and overgrowth of long bones and vertebrae, which are caused by an increase in proliferation. Therefore, it seems that PTHrP and FGFR3 serve as positive and negative regulators on the chondrocyte proliferation, respectively. In this paper, we review our recent studies on the histological abnormality of long bone seen in PTHrP gene deficient- and FGFR3 gene deficient-mice.
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Xie CX, Ozawa H, Yang YM, Kawata M. Immunohistochemical study of nucleoporin p62 in the hippocampus and hypothalamus of the rat brain. Neuroreport 2000; 11:2965-7. [PMID: 11006975 DOI: 10.1097/00001756-200009110-00027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We immunohistochemically studied the distribution of nucleoporin p62 in the hippocampus and hypothalamus of rat brain. Previous reports have shown the presence of p62-immunoreactivity (ir) in the nuclear rim in the non-neuronal cells, but the present study showed that of p62-ir within the nucleus in addition to the nuclear rim in the neuronal cells of the hippocampus and hypothalamic nuclei; in these areas the glucocorticoid receptor (GR) undergoes nucleocytoplasmic translocation determined by ligand. We analyzed the expression of p62-ir after adrenalectomy (ADX). ADX changed the localization of GR-ir from the nucleus to the cytoplasm, but did not change the localization or immunoreactivity of p62, suggesting that nucleoporin p62 is stable regardless of intracellular signal transduction between the cytoplasm and the nucleus.
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Ozawa H, Chancellor MB, Ding YY, Nasu Y, Yokoyama T, Kumon H. Noninvasive urodynamic evaluation of bladder outlet obstruction using Doppler ultrasonography. Urology 2000; 56:408-12. [PMID: 10962304 DOI: 10.1016/s0090-4295(00)00684-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Previously we had developed a new method of noninvasive urodynamics using color Doppler ultrasound. Using this technique, we attempted to identify parameters that would diagnose bladder outlet obstruction (BOO). METHODS Twenty-two men who underwent pressure-flow urodynamic studies were included. Color scale transperineal ultrasound and uroflowmetry data were analyzed by custom-made software. The maximum flow velocities in the entire prostatic urethra (V(0)), in the distal prostatic urethra just proximal to the external urethral sphincter (V(1)), and in the membranous urethra (V(2)) were obtained. Corresponding functional cross-sectional areas of the urethra at these three sites (A(0), A(1), and A(2)) were calculated as Qmax/V. The velocity ratio (VR), which was equal to V(1)/V(2), was also calculated as a parameter. All these parameters obtained by the velocity-flow urodynamics were compared with the Abrams-Griffiths number (AG). RESULTS From the x-y plots obtained, VR correlated best with AG, with Spearman's rho of 0. 728. A(0) and A(1) had rho values of -0.461 and -0.708 against AG, respectively. All men with VR exceeding 1.6 had obstruction, whereas those with VR less than 1.1 did not. CONCLUSIONS The VR was found to be the best parameter for diagnosing BOO. When prostatic urethral obstruction was present, the velocity in the prostatic urethra would be high but the velocity slows down to 62.5% or greater immediately below the sphincter. We believe that noninvasive pressure-flow-like urodynamic evaluation based on Doppler ultrasound has clear potential for diagnosing BOO.
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Watanabe J, Amizuka N, Noda T, Ozawa H. Cytochemical and ultrastructural examination of apoptotic odontoclasts induced by bisphosphonate administration. Cell Tissue Res 2000; 301:375-87. [PMID: 10994783 DOI: 10.1007/s004410000242] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Since odontoclasts share similar characteristics with osteoclasts, this study has examined whether odontoclasts exhibit cytological alteration after treatment with bisphosphonate, which induces apoptosis of osteoclasts. After the administration of bisphosphonate to 6-day-old rabbits, many odontoclasts detached from the dentine surface of the deciduous teeth, resulting in the reduction of tartrate-resistant acid phosphatase (TRAP-ase) and immunoreactivity for cathepsin K. Transmission electron microscopy revealed a number of odontoclasts showing poorly developed or a lack of ruffled borders, a Golgi apparatus markedly reduced in size, and numerous cytoplasmic vesicles. The bisphosphonate-treated odontoclasts displayed fragmented DNA in the pyknotic nuclei evidenced by terminal deoxynucleotidyl-transferase-mediated dUTP-biotin nick-end labeling, indicating that bisphosphonate can induce apoptosis of the odontoclasts. Ultrastructural observations of the apoptotic odontoclasts revealed condensed heterochromatin at the margin of the nuclear envelope, assembled arrays of rough endoplasmic reticulum, and many vacuoles and vesicles. Some apoptotic odontoclasts showed ladder-like structures between the adjacent nuclear envelopes, enlargement of the nuclear envelopes, and the formation of a ribosome-like granular structure in the nuclei. Thus, odontoclasts are able to undergo apoptosis after bisphosphonate treatment; this results in cytological alterations, including reduced resorption activity and the inhibition of protein synthesis/transport as indicated by the diminished TRAPase and cathepsin K and the poorly developed Golgi apparatus, respectively. Nuclear alteration as evidenced by the appearance of ladder-like and ribosome-like structures was characteristic of apoptotic odontoclasts.
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Ozawa H, Noma S, Yoshida Y, Sekine H, Hashimoto T. Acute disseminated encephalomyelitis associated with poliomyelitis vaccine. Pediatr Neurol 2000; 23:177-9. [PMID: 11020647 DOI: 10.1016/s0887-8994(00)00167-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A 6-year-old female patient with acute disseminated encephalomyelitis associated with poliomyelitis vaccine virus is reported. She had a history of high fever, headache, and gait disturbance. Neurologic examination confirmed spastic triparesis, urinary incontinence, diminution of tactile sensation, and vision deterioration. Hemography, serum laboratory findings, and urinalysis were normal. The cerebrospinal fluid was clear, with normal pressure, 9 leukocytes/mm(3), and 27 mg/dL protein, but the myelin basic protein was elevated to 10.7 ng/mL. T(2)-weighted magnetic resonance imaging disclosed multifocal high-intensity lesions of the spinal cord. The serum polio virus type 2 antibody titer was raised in the acute phase, and polio vaccine virus type 2 was detected in viral cultures of the cerebrospinal fluid and pharynx swab and had undergone an A-G neurovirulence mutation at nucleotide 481. Finally, she had human leukocyte antigen (HLA)-Cw3 and HLA-DR2, to which multiple sclerosis is related in Japan. Thus the cause of ADEM may have been related to her HLA type.
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