101
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Inoue C, Hayashi A, Yoshizawa T, Sato A, Shoji S. [Effect of intravenous immunoglobulin therapy in a case of idiopathic recurrent brachial and lumbosacral plexopathy]. Rinsho Shinkeigaku 1999; 39:661-4. [PMID: 10502994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
We report a case of a 23-year-old woman with idiopathic brachial and lumbosacral plexopathy who presented a relapsing course of weakness and numbness following acute onset of pain in the right shoulder or pelvic girdle area. On her first admission, the patient recovered gradually with oral prednisolone. But after about 1 year, her symptoms worsened. In the second admission, oral prednisolone had no effect on her symptoms, so intravenous immunoglobulin (IVIG; 0.1 g/kg/day, 5 days) therapy was tried. The patient improved about 2 weeks after IVIG therapy. About 1 year later, her symptoms worsened and was administered again. In the third admission, IVIG therapy of which dose was the same as that in the previous admission had an effect on her symptoms. The dose of IVIG in our case was relatively low, compared with those in cases reported before (0.2-2 g/kg/day). This findings suggest that a relatively low-dose IVIG therapy is effective for idiopathic plexopathy.
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102
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Kato S, Takeyama K, Kitanaka S, Murayama A, Sekine K, Yoshizawa T. In vivo function of VDR in gene expression-VDR knock-out mice. J Steroid Biochem Mol Biol 1999; 69:247-51. [PMID: 10418998 DOI: 10.1016/s0960-0760(99)00042-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Vitamin D exerts many biological actions through nuclear vitamin D receptor (VDR)-mediated gene expression. The transactivation function of VDR is activated by binding 1alpha,25-dihydroxyvitamin D3[1alpha,25(OH)2D3], an active form of vitamin D. Conversion from 25(OH)D3 is finely regulated in kidney by 25(OH)D3 1alpha-hydroxylase[25(OH)D 1alpha-hydroxylase], keeping serum levels of 1alpha,25(OH)2D3 constant. Deficiency of vitamin D and mutations in the genes like VDR (type II genetic rickets) are known to cause rickets like lowered serum calcium, alopecia and impaired bone formation. However, the molecular basis of vitamin D VDR system in the vitamin D action in intact animals remained to be established. In addition, the 1alpha-hydroxylase gene from any species had not yet been cloned, irrespective of its biological significance and putative link to the type I genetic rickets. We generated VDR-deficient mice (VDR KO mice). VDR KO mice grew up normally until weaning, but after weaning they developed abnormality like the type II rickets patients. These results demonstrated indispensability of vitamin D-VDR system in mineral and bone metabolism only in post-weaning life. Using a newly developed cloning system, we cloned the cDNA encoding a novel P450 enzyme, mouse and human 1alpha-hydroxylase. The study in VDR KO mice demonstrated the function of liganded VDR in the negative feed-back regulation of 1alpha,25(OH)2D3 production. Finally, from the analysis of type I rickets patients, we found missense genetic mutations in 1alpha-hydroxylase, leading to the conclusion that this gene is responsible for the type I rickets.
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103
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Yoshizawa T, Fujita T, Mizusawa H, Shoji S. L-threo-3,4-dihydroxyphenylserine enhances the orthostatic responses of plasma renin activity and angiotensin II in multiple system atrophy. J Neurol 1999; 246:193-7. [PMID: 10323317 DOI: 10.1007/s004150050333] [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: 11/26/2022]
Abstract
We evaluated the effect of L-threo-3,4-dihydroxyphenylserine (L-threo-DOPS) on the response of blood pressure and vasoactive factors during head-up tilt in patients with multiple system atrophy (MSA). After the daily oral administration of 300 mg L-threo-DOPS for 2 weeks we observed a significant reduction in the decline of systolic blood pressure during 60 degrees head-up-tilt. In concordance with this result, we detected significant increases in postural changes in plasma renin activity and angiotensin II following L-threo-DOPS treatment. The enhanced responses of these vasoactive mediators by L-threo-DOPS during head-up tilt may contribute to the improvement in orthostatic hypotension in patients with MSA.
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104
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Takeda S, Yoshizawa T, Nagai Y, Yamato H, Fukumoto S, Sekine K, Kato S, Matsumoto T, Fujita T. Stimulation of osteoclast formation by 1,25-dihydroxyvitamin D requires its binding to vitamin D receptor (VDR) in osteoblastic cells: studies using VDR knockout mice. Endocrinology 1999; 140:1005-8. [PMID: 9927335 DOI: 10.1210/endo.140.2.6673] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Previous studies have shown that 1,25-dihydroxyvitamin D [1,25(OH)2D] plays important roles in the formation of osteoclasts through its actions on osteoblastic cells. We have generated mice lacking vitamin D receptor (VDR) by gene targeting (VDR-/-). These mice had tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts, and exhibited similar levels of parameters for bone resorption to those in wild type mice. The present studies were undertaken to clarify whether effects of 1,25(OH)2D on osteoclast formation require VDR in osteoblasts, and to examine mechanisms of the formation of osteoclasts without VDR-mediated actions using VDR-/- mice. When wild-type calvarial osteoblasts and spleen cells were co-cultured with 1,25(OH)2D, TRAP-positive osteoclasts were formed regardless of the genotypes of spleen cells. In contrast, when osteoblasts from VDR-/- mice were co-cultured, no osteoclasts could be formed even with wild-type spleen cells. Parathyroid hormone and interleukin-1alpha stimulated osteoclast formation by co-cultures from VDR-/- mice, and the generated osteoclasts showed resorbing activity. These results demonstrate that VDR-mediated actions of 1,25(OH)2D in osteoblasts are essential for osteoclast formation by 1,25(OH)2D, and that functionally intact osteoclasts can be formed without 1,25(OH)2D actions under stimulations by other agents. It is suggested that osteoclastic bone resorption can be maintained without 1,25(OH)2D actions by other stimulatory agents.
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105
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Sekine K, Ohuchi H, Fujiwara M, Yamasaki M, Yoshizawa T, Sato T, Yagishita N, Matsui D, Koga Y, Itoh N, Kato S. Fgf10 is essential for limb and lung formation. Nat Genet 1999; 21:138-41. [PMID: 9916808 DOI: 10.1038/5096] [Citation(s) in RCA: 903] [Impact Index Per Article: 36.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The interactions between fibroblast growth factors (FGF) and their receptors have important roles in mediating mesenchymal-epithelial cell interactions during embryogenesis. In particular, Fgf10 is predicted to function as a regulator of brain, lung and limb development on the basis of its spatiotemporal expression pattern in the developing embryo. To define the role of Fgf10, we generated Fgf10-deficient mice. Fgf10-/- mice died at birth due to the lack of lung development. Trachea was formed, but subsequent pulmonary branching morphogenesis was disrupted. In addition, mutant mice had complete truncation of the fore- and hindlimbs. In Fgf10-/- embryos, limb bud formation was initiated but outgrowth of the limb buds did not occur; however, formation of the clavicles was not affected. Analysis of the expression of marker genes in the mutant limb buds indicated that the apical ectodermal ridge (AER) and the zone of polarizing activity (ZPA) did not form. Thus, we show here that Fgf10 serves as an essential regulator of lung and limb formation.
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106
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Yoshizawa T, Matsuzawa M. Collisions of high-Rydberg atoms in circular states with He. ACTA ACUST UNITED AC 1999. [DOI: 10.1088/0022-3700/17/14/006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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107
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Watanabe S, Wang XE, Hirose M, Osada T, Yoshizawa T, Tanaka H, Itatsu T, Nakajima M, Yamamoto J, Miwa H, Miyazaki A, Awaya A, Sato N. A neurotrophic pyrimidine compound, MS-818, enhances EGF-induced restoration of gastric epithelial wounds in vitro. J Clin Gastroenterol 1999; 27 Suppl 1:S105-9. [PMID: 9872506 DOI: 10.1097/00004836-199800001-00017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
MS-818 is a novel synthetic pyrimidine compound that stimulates nerve regeneration and promotes synthesis of various growth factors and differentiation of astrocytes. Effects of MS-818 on gastric epithelial cells were assessed using a wound repair model with primary cultured gastric epithelial cells from rabbits. A round wound with a constant cell-free area was created and the process of restoration was monitored by measuring wound size every 12 h. Cell proliferation was monitored by sequential staining with BrdU. As previously reported, EGF (10 ng/ml) accelerated wound repair by promoting cell migration and proliferation. Although MS-818 alone had no effects, MS-818 (10-100 microM) enhanced EGF-induced acceleration of gastric epithelial restoration, including cell migration and proliferation. Although the detailed mechanism of action of this agent is still unclear, MS-818 might have favorable effects on in vivo gastric mucosal repair.
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108
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Ishiguro T, Uno Y, Takahara M, Abe C, Yoshizawa T, Yoshizawa A. [Drug consultation for patients who present with symptoms like dementia]. Gan To Kagaku Ryoho 1998; 25 Suppl 4:565-8. [PMID: 9884641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
It is a lowering of compliance in taking drugs of patients who present with symptoms like dementia that being impairment in a therapy for disease. We started drug consultation to that one at home care, because of improvement of non-compliance in taking drugs. Improvement of consciousness in taking drugs for patients and consciousness in necessity of taking drugs for their family that be brought about by our drug consultation could be made progress of compliance in taking drugs.
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109
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Yoshizawa A, Ajisaka R, Yoshizawa T. [Transition in home care service in our hospital]. Gan To Kagaku Ryoho 1998; 25 Suppl 4:535-8. [PMID: 9884635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Progress of medical team ability, including analgesic treatment and nursing care, and a building closer connections with welfare services including visiting nurse station, is necessary for home medical care for the terminal cancer patient.
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110
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Masumoto H, Yoshizawa T, Sorimachi H, Nishino T, Ishiura S, Suzuki K. Overexpression, purification, and characterization of human m-calpain and its active site mutant, m-C105S-calpain, using a baculovirus expression system. J Biochem 1998; 124:957-61. [PMID: 9792919 DOI: 10.1093/oxfordjournals.jbchem.a022213] [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: 11/13/2022] Open
Abstract
Recombinant human m-calpain was produced in a soluble form at a level of 20 mg/liter of Sf-9 cell culture by the coexpression of recombinant human m-calpain large (m80K) and small (30K) subunits using a baculovirus expression system. The expressed m-calpain was purified by sequential column chromatographies on DEAE-Toyopearl, gel-filtration, and Mono Q by the same method used to purify native m-calpain. The recombinant m-calpain had a specific activity of 691 U/mg and a Ka value (Ca2+ requirement for 50% caseinolysis activity) of 0.4 mM, which are essentially identical to those of native rabbit m-calpain. A mutant m-calpain large subunit, m-C105S-80K, where the active-site cysteine-105 is converted to serine by site-directed mutagenesis, was coexpressed with 30K in Sf-9 cells, purified, and characterized. m-C105S-calpain does not degrade casein nor an artificial tetra-peptide substrate, succinyl-Leu-Leu-Val-Tyr-MCA. Further, it shows no autolytic activity with Ca2+. This is the first report of the large-scale production of a fully active m-calpain species in the baculovirus system.
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111
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Islam Z, Nagase M, Ota A, Ueda S, Yoshizawa T, Sakato N. Structure-function relationship of T-2 toxin and its metabolites in inducing thymic apoptosis in vivo in mice. Biosci Biotechnol Biochem 1998; 62:1492-7. [PMID: 9757554 DOI: 10.1271/bbb.62.1492] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recently we found that a single administration of T-2 toxin (T-2), a trichothecene mycotoxin, into mice induced DNA fragmentation, a biochemical hallmark of apoptosis, in the thymus. In this study, we investigated the effective chemical structure(s) of T-2-derived metabolites capable of inducing thymic apoptosis in vivo in mice. Metabolic conversion of T-2 to 3'-hydroxy-T-2 toxin (3'-OH-T-2) did not diminish the apoptosis-inducing activity, since essentially the same level of fragmented DNA was detected in the thymus taken from mice injected with either T-2 or 3'-OH-T-2. In contrast, hydrolysis of T-2 and 3'-OH-T-2 at the carbon-4 (C-4) position to HT-2 toxin (HT-2) and 3'-hydroxy-HT-2 toxin (3'-OH-HT-2), respectively, greatly decreased the level of DNA fragmentation. Similarly, hydrolysis of T-2 at the carbon-8 (C-8) position to neosolaniol strongly diminished its ability to induce DNA fragmentation. T-2 tetraol, having no ester groups, was unable to induce apoptosis. Based on the data presented in this study, we concluded that both the acetyl group at the C-4 position and the isovaleryl or 3'-hydroxyisovaleryl group at the C-8 position of the T-2 molecule are important for inducing cell death through apoptosis in the thymus.
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112
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Saeki Y, Atogami F, Hiraishi M, Furuta N, Yoshizawa T. Impairment of autonomic function induced by posture change in postmenopausal women. J Womens Health (Larchmt) 1998; 7:575-82. [PMID: 9650158 DOI: 10.1089/jwh.1998.7.575] [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: 11/12/2022] Open
Abstract
This study was designed to determine if there is a difference in autonomic regulation induced by posture change between postmenopausal and young women. To evaluate autonomic nervous system function, spectral analysis of heart rate variability (HRV) was done in postmenopausal women (n = 13, 46-59 years of age), age-matched men (n = 8, 45-55 years of age), and young women (n = 10, 20-37 years of age) for 3-min periods of controlled frequency breathing (15 breaths/min) in supine followed by sitting positions. In the supine position, the R-R interval variation in older persons decreased significantly compared with that during the follicular phase in young women. Furthermore, the high-frequency (HF) components of HRV, which reflect only parasympathetic activity, were lower in older subjects than in young women. Following a change of position from supine to sitting, the HF component did not change significantly in the postmenopausal women or the men, but the low/high frequency (LF/HF) component ratio, which reflects the balance of autonomic nerve activities, increased significantly in the men. These results suggest that cardiac parasympathetic tone may be reduced in older persons in comparison with young women. Furthermore, arterial baroreflex control of parasympathetic nerve activity caused by posture changes is impaired in the postmenopausal women and aged-matched men. The baroreflex control of the sympathetic component is maintained in the men but not in the postmenopausal women. These differences might result in part from changes in the level of female hormones.
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113
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Ali N, Yamashita A, Yoshizawa T. Natural co-occurrence of aflatoxins and Fusarium mycotoxins (fumonisins, deoxynivalenol, nivalenol and zearalenone) in corn from Indonesia. FOOD ADDITIVES AND CONTAMINANTS 1998; 15:377-84. [PMID: 9764205 DOI: 10.1080/02652039809374655] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Sixteen corn samples collected from Indonesia were analysed for aflatoxins (AF), fumonisins (FM), trichothecenes and zearalenone (ZEA) using high-performance liquid chromatography and gas chromatography-mass spectrometry. AF were detected in 11 (69%) samples at a mean level of 119 ng/g (maximum 487 ng/g) and FM in all of the samples at a mean level of 895 ng/g (maximum 2970 ng/g). Deoxynivalenol (DON), nivalenol (NIV) and ZEA were each detected in two (12%) samples; 21 and 32 ng/g, 49 and 169 ng/g, and 11 and 12 ng/g, respectively. All of the AF-contaminated samples were co-contaminated with FM. Mycological study showed all of the AF-contaminated samples were infected with A. flavus/A. parasiticus, and the FM-contaminated samples were either infected with F. moniliforme (50%), F. proliferatum (12%), F. nygamai (6%) or F. decemcellulare (38%). Supportive mycological studies showed that Fusarium species isolated from Indonesian corn were capable of producing a mean level of 10,000 micrograms/g FM. Based on these results, the correlation between FM-producers and AF-producers on kernel infection and contamination of these mycotoxins in corn was discussed. This is the first report on the natural co-occurrence of AF and various Fusarium mycotoxins, including DON and NIV in corn from Indonesia, and also the first report on the natural occurrence of DON in corn from hot areas of Southeast Asia.
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114
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Islam Z, Nagase M, Yoshizawa T, Yamauchi K, Sakato N. T-2 toxin induces thymic apoptosis in vivo in mice. Toxicol Appl Pharmacol 1998; 148:205-14. [PMID: 9473527 DOI: 10.1006/taap.1997.8338] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A single intraperitoneal injection of T-2 toxin (0.35, 1.75, or 3.5 mg/kg body wt) induced time- and dose-dependent thymic atrophy in young female BALB/c mice. T-2 toxin (1.75 mg/kg) induced maximal atrophy by day 3 with complete recovery by day 7. Flow cytometric analysis showed that the CD4(+)CD8(+) double positive thymocyte population decreased markedly. Histopathological examination of the thymus indicated that the pattern of cell death in the thymocytes had a characteristic apoptotic morphology with cell shrinkage and nuclear condensation. The in vivo effects of T-2 toxin included the induction of DNA fragmentation of approximately 200 base pairs in ladder form and cell death in thymocytes. Furthermore, flow cytometric analysis of PI-stained thymocytes from animals dosed with T-2 toxin revealed the formation of apoptotic cells. Of nine kinds of trichothecene mycotoxins tested, T-2 toxin appeared to be the most potent agent to induce apoptosis in the thymus. We sought insight into the mechanism of T-2 toxin-induced apoptosis in vivo. Administration of the protein synthesis inhibitor, CHX (15 mg/kg ip), 5 min after T-2 toxin (1.75 mg/kg ip) inhibited the induction of apoptosis in thymocytes, suggesting that the de novo protein synthesis was necessary. By using adrenalectomized mice and anti-TNF-alpha antibody-injected mice, it was shown that neither endogenous glucocorticoid nor TNF-alpha appeared to be involved in the apoptotic process. Taken together, these findings suggest that T-2 toxin-induced thymic atrophy is associated with cell death through a mechanism of apoptosis.
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115
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Fujimori H, Matsumura A, Yamamoto T, Shibata Y, Yoshizawa T, Nakagawa K, Yoshii Y, Nose T, Sakata I, Nakajima S. Tumor specific contrast enhancement study of Mn-metalloporphyrin (ATN-10)--comparison of rat brain tumor model, cytotoxic and vasogenic edema models. ACTA NEUROCHIRURGICA. SUPPLEMENT 1998; 70:167-9. [PMID: 9416311 DOI: 10.1007/978-3-7091-6837-0_51] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
ATN-10, Mn-metalloporphyrin, has been developed as a tumor selective contrast agent for magnetic resonance (MR) imaging. To investigate the tumor specificity of ATN-10, we produced three experimental in vivo models; rat bran tumor (9L glioma) model, vasogenic (cold injury) and cytotoxic brain edema (24-hour MCA occlusion) models. The time course of contrast enhancement was compared after intravenous injection of ATN-10 or Gd-DTPA, measuring the signal intensity of the region of interest. After ATN-10 administration, the 9L glioma model showed early (5 min) and delayed (24 hr-) peak enhancement whereas the cold injury model showed only early enhancement and the 24-hour MCA occlusion model did not show significant enhancement. After Gd-DTPA administration, all three models showed similar pattern of only early enhancement. As a contrast agent for MR imaging, ATN-10 showed different behavior than Gd-DTPA in demonstrating the blood-brain barrier disruption and moreover ATN-10 showed selective enhancement in experimental brain tumors.
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116
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Le D, Das S, Wang YF, Yoshizawa T, Sasaki YF, Takasu M, Nemes A, Mendelsohn M, Dikkes P, Lipton SA, Nakanishi N. Enhanced neuronal death from focal ischemia in AMPA-receptor transgenic mice. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1997; 52:235-41. [PMID: 9495544 DOI: 10.1016/s0169-328x(97)00261-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Excitatory amino acid (EAA) receptors play an important role in neuronal cell death in acute cerebral ischemia. Blocking the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) subtype of EAA receptor has been shown to reduce cell death in global cerebral ischemia. However their role in focal stroke, although suggestive, has remained more contentious. To clarify this issue, we generated transgenic mice overexpressing the AMPA receptor (AMPAR) subunit GluR2-flip which would increase AMPAR-mediated currents. Excitatory neurons in these transgenic mice are thus predicted to be more susceptible than wild-type neurons to EAA (glutamate)-induced excitotoxic damage. Consistent with this prediction, cultured neurons from transgenic mice had a lower LD50 for exposure to glutamate (10(-3)-10(-5) M for 5 min) compared to wild-type neurons. Moreover, transgenic mice subjected to permanent focal ischemia of the middle cerebral artery (MCA) using the intralumenal filament model sustained larger infarctions compared to wild-type controls. Hence we have developed a genetic mouse model that demonstrates the crucial role of AMPAR containing GluR2-flip in the pathogenesis of focal hypoxic-ischemic neuronal cell death. This model will be a valuable tool in elucidating molecular mechanisms of glutamate excitotoxicity and evaluating the efficacy of glutamate receptor antagonists in attenuating post-ischemic neuronal cell death.
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MESH Headings
- Alternative Splicing
- Animals
- Brain/metabolism
- Brain/pathology
- Cell Death
- Cerebral Cortex/metabolism
- Cerebral Cortex/pathology
- Crosses, Genetic
- Disease Susceptibility
- Female
- Genetic Variation
- Heterozygote
- Ischemic Attack, Transient/pathology
- Ischemic Attack, Transient/physiopathology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, Transgenic
- Neocortex/metabolism
- Neocortex/pathology
- Neurons/pathology
- Neurons/physiology
- Polymerase Chain Reaction
- Receptors, AMPA/biosynthesis
- Receptors, AMPA/genetics
- Receptors, AMPA/physiology
- Transcription, Genetic
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117
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Ishiguro T, Takahara M, Uno Y, Abe C, Yoshizawa A, Yoshizawa T, Ajisaka R. [Drug consultation and at home care--the present situation and the point at issue in our hospital]. Gan To Kagaku Ryoho 1997; 24 Suppl 4:551-4. [PMID: 9429565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We began drug consultation in our hospital and at home care about one year ago, because of progress in the quality of medical care. As the method for drug consultation, we tried to educate patients using our own pamphlets. It was assumed that the education was important not only for the patients but also for their family. Again, it was assumed that the usefulness of a conference with doctors, nurses, MSW and us made for better compliance in taking drugs, assured early detection of side effects and better management of the disease. With home care, it is supposed that the drug consultation will be carried out by clinical pharmacists will make for progress in the quality of medical care.
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118
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Yoshizawa A, Ishiguro T, Yoshizawa T, Idegawa C, Ajisaka R. [Transition in nutritional management and the home care service system in our hospital]. Gan To Kagaku Ryoho 1997; 24 Suppl 4:547-50. [PMID: 9429564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
During the past two years, Kaname-cho Hospital has been diligent in meeting the health care needs of its patients through its home care service. In nutritional management, considering the activity of daily living (ADL) and the burden of the family, gastrostomy and intravenous hyperalimentation (IVH) have been increased. Although we started with services provided by physicians, nurses, and medical social workers (MSW), recently clinical pharmacists and dieticians have entered our home care services. Due to the strong support of our staff, it is now possible for Kaname-cho Hospital to provide a very fine, efficient home care service.
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119
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Yoshizawa T, Yamakawa-Kobayashi K, Hamaguchi H, Shoji S. Alpha1-antichymotrypsin polymorphism in Japanese cases of Alzheimer's disease. J Neurol Sci 1997; 152:136-9. [PMID: 9415533 DOI: 10.1016/s0022-510x(97)00162-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We examined the possible involvement of alpha1-antichymotrypsin (ACT) polymorphism in the risk for Alzheimer's disease (AD) in a Japanese population. No differences between AD and control subjects have been shown in the genotype distributions and allele frequencies of ACT. No modification of the risk for AD was observed, either alone or in combination with the apolipoprotein epsilon4 (ApoE-4) allele. Our results from a Japanese population failed to confirm the previous data in which the ACT polymorphism was shown to affect the ApoE-4-associated risk for AD.
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120
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Imai H, Terakita A, Tachibanaki S, Imamoto Y, Yoshizawa T, Shichida Y. Photochemical and biochemical properties of chicken blue-sensitive cone visual pigment. Biochemistry 1997; 36:12773-9. [PMID: 9335534 DOI: 10.1021/bi970809x] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Through low-temperature spectroscopy and G-protein (transducin) activating experiments, we have investigated molecular properties of chicken blue, the cone visual pigment present in chicken blue-sensitive cones, and compared them with those of the other cone visual pigments, chicken green and chicken red (iodopsin), and rod visual pigment rhodopsin. Irradiation of chicken blue at -196 degrees C results in formation of a batho intermediate which then converts to BL, lumi, meta I, meta II, and meta III intermediates with the transition temperatures of -160, -110, -40, -20, and -10 degrees C. Batho intermediate exhibits an unique absorption spectrum having vibrational fine structure, suggesting that the chromophore of batho intermediate is in a C6-C7 conformation more restricted than those of chicken blue and its isopigment. As reflected by the difference in maxima of the original pigments, the absorption maxima of batho, BL, and lumi intermediates of chicken blue are located at wavelengths considerably shorter than those of the respective intermediates of chicken green, red and rhodopsin, but the maxima of meta I, meta II, and meta III are similar to those of the other visual pigments. These facts indicate that during the lumi-to-meta I transition, retinal chromophore changes its original position relative to the amino acid residues which regulate the maxima of original pigments through electrostatic interactions. Using time-resolved low-temperature spectroscopy, the decay rates of meta II and meta III intermediates of chicken blue are estimated to be similar to those of chicken red and green, but considerably faster than those of rhodopsin. Efficiency in activating transducin by the irradiated chicken blue is greatly diminished as the time before its addition to the reaction mixture containing transducin and GTP increases, while that by irradiated rhodopsin is not. The time profile is almost identical with those observed in chicken red and green. Thus, the faster decay of enzymatically active state is common in cone visual pigments, independent of their spectral sensitivity.
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Saeki Y, Atogami F, Takahashi K, Yoshizawa T. Reflex control of autonomic function induced by posture change during the menstrual cycle. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1997; 66:69-74. [PMID: 9334995 DOI: 10.1016/s0165-1838(97)00067-2] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This study was designed to determine whether autonomic regulation induced by posture changes varies during the menstrual cycle. Heart rate variability (HRV) was analyzed in women with normal menstrual cycles (n = 10, age range 20-37 years) during 3 min periods of controlled frequency breathing (15 breaths/min) in supine followed by sitting positions. In a supine or sitting position, high frequency (HF) components of HRV, which reflects only parasympathetic activity, were significantly high in the follicular phase compared with those in the menstrual phase, suggesting that parasympathetic nerve activity increases in this phase. Following the change of position to sitting from supine, the HF component decreased significantly in the menstrual, ovulatory and luteal phases, but not the follicular or premenstrual phase. After changing the position to sitting, the low to high frequency component ratio, which reflects the balance of autonomic nerve activities, was increased significantly in the menstrual, luteal and premenstrual phases, indicating that sympathetic nerve activities in these phases became predominant by the sitting position. These results suggest that parasympathetic nerve activity is predominant in the follicular phase, resulting in an impairment of baroreflex caused by posture changes. Moreover, baroreflex control of the sympathetic component, not the parasympathetic component, increases in the premenstrual phase, while the reflex response of the sympathetic component is less in the ovulatory phase compared with the menstrual or luteal phase. We concluded that baroreflex regulation of autonomic functions induced by changing positions is modified during the menstrual cycle. A difference of a balance of ovarian hormones may be responsible for these changes of autonomic functions during the menstrual cycle.
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Yamamoto Y, Yoshizawa T, Kamio S, Aoki O, Kawamata Y, Masushige S, Kato S. Interactions of transthyretin (TTR) and retinol-binding protein (RBP) in the uptake of retinol by primary rat hepatocytes. Exp Cell Res 1997; 234:373-8. [PMID: 9260907 DOI: 10.1006/excr.1997.3642] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The mechanism by which cells take up retinol from retinol-binding protein (RBP) and the role of the RBP-transthyretin (TTR) complex remain unclear. Here we report on retinol uptake through the RBP-TTR complex by primary cultured rat hepatocytes (parenchymal cells, PC) and nonparenchymal cells (NPC) following incubation with [3H]retinol-RBP or the [3H]retinol-RBP-TTR complex under several conditions. The cellular accumulation of retinol was time and temperature dependent in both PC and NPC. Analysis by HPLC showed that the incorporated [3H]retinol in NPC was mainly converted to retinyl ester, although in PC it remained mainly as unesterified retinol. However, the amount of retinol taken up from the RBP-TTR complex was nearly twofold greater than that from RBP alone. The uptake of [3H]retinol from protein-bound retinol was inhibited by an excess of either retinol-RBP or retinol-RBP-TTR complex. Moreover, retinol uptake through the RBP-TTR complex was inhibited by an excess of free TTR. From these results we postulate that TTR may take part as a positive regulator in the delivery of RBP-bound retinol from plasma, possibly by a membrane receptor, and that retinol uptake takes place preferentially from the RBP-TTR complex into both PC and NPC. The uptake of [3H]retinol (2 microM) by PC was saturated, whereas uptake by NPC was not. These results indicate that the physiological importance of TTR in retinol delivery may be especially important to vitamin A-storing stellate (Ito) cells in the NPC fraction.
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Yoshizawa T, Handa Y, Uematsu Y, Takeda S, Sekine K, Yoshihara Y, Kawakami T, Arioka K, Sato H, Uchiyama Y, Masushige S, Fukamizu A, Matsumoto T, Kato S. Mice lacking the vitamin D receptor exhibit impaired bone formation, uterine hypoplasia and growth retardation after weaning. Nat Genet 1997; 16:391-6. [PMID: 9241280 DOI: 10.1038/ng0897-391] [Citation(s) in RCA: 757] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
1 alpha,25-Dihydroxyvitamin D3[1 alpha,25(OH)2D3], an active form of vitamin D, has roles in many biological phenomena such as calcium homeostasis and bone formation, which are thought to be mediated by the 1 alpha,25(OH)2D3 receptor (VDR), a member of the nuclear hormone receptor superfamily. However, the molecular basis for the actions of 1 alpha,25(OH)2D3 in bone formation, its role during development and VDR genetic polymorphisms for predicting bone mineral density are uncertain. To investigate the functional role of VDR, we generated mice deficient in VDR by gene targeting. We report here that in VDR null mutant mice, no defects in development and growth were observed before weaning, irrespective of reduced expression of vitamin D target genes. After weaning, however, mutants failed to thrive, with appearance of alopoecia, hypocalcaemia and infertility, and bone formation was severely impaired as a typical feature of vitamin D-dependent rickets type II (refs 8, 9). Unlike humans with this disease, most of the null mutant mice died within 15 weeks after birth, and uterine hypoplasia with impaired folliculogenesis was found in female reproductive organs. These defects, such as alopoecia and uterine hypoplasia, were not observed in vitamin D-deficient animals. The findings establish a critical role for VDR in growth, bone formation and female reproduction in the post-weaning stage.
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Yoshizawa T, Anno I, Matsumura A, Enomoto T, Yamada H, Muraki S, Itai Y, Nose T. [Functional MRI employing diazepam; a proposal of neuropharmacological fMRI]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1997; 55:1712-8. [PMID: 9233014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Employing the active benzodiazepine receptor (BZR) ligands, we have used BOLD fMRI to elucidate the effects of these drugs on brain function. The sequential MRI was performed with a 1.5T clinical scanner (Philips GYROSCAN) using a FLASH sequence with the following parameters: TR/TE, 100/45 msec; flip angle, 25 degrees; matrix size, 128*128; 2 averages; for 64 image acquisitions in 32 min. First, 2 mg of diazepam was administrated intravenously at the beginning of the 5th, 15th, 25th, and 35th acquisitions. Then, flumazenil was administrated at the beginning of the 45th (0.2 mg) and 55th (0.3 mg) acquisitions in order to reverse the effect of diazepam. Data processing was made employing Akaike Information Criterion to detect if there were intensity changes after the medication among the trends of intensity changes. Diazepam administration decreased the intensity for a while and flumazenil increased one. In the case of the left frontal glioma with focal epileptogenicity, intensity changes were detected around the tumor. Since the neuronal function consists of the trans-neuronal communications employing neurotransmitters, the result on the modulation of this passage depends on the neuronal function related to the transmitter: gamma-amino butyric acid (GABA) in this instance for the effects of these medications to epilepsy. The change in the local blood flow is the result of the local neuronal activity. Therefore, we speculate that this neuropharmacological functional MR image may reflect the neuronal function related to the GABAegic neurotransmitter system. In addition to elucidating basic neurotransmitter function mechanisms, we believe this technique may have clinical utility in the pre-surgical evaluation of patients with intractable seizure disorders. In this respect, this paper presents a new spectrum of fMRI that is capable to study a part of neurotransmitter function employing the BZR ligands, reversing the effect of the agonist with the competitive antagonist, for the first experience, to propose the neuropharmacological functional MR images to have clinical utility in patients with intractable epilepsy in the interictal state.
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Miyamoto F, Saeki M, Yoshizawa T. Improved protocol for an oxygen electrode method for determining hydrogen peroxide in foods. J AOAC Int 1997; 80:681-7. [PMID: 9170662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
An oxygen electrode method for determining residual hydrogen peroxide in foods has been further improved. Pretreatment, which includes extraction and neutralization, is done in a hydrogen peroxide extraction apparatus with nitrogen gas bubbling. The hydrogen peroxide concentration of the sample is corrected by subtracting the sample blank value, obtained for the sample through catalase treatment. Bubbling with nitrogen gas effectively minimized the sample blank value, making this method suitable for accurate determination of trace amounts of hydrogen peroxide in foods. Recoveries of hydrogen peroxide added at 1-10 micrograms/g were 77.8-107.1% by the present method. These recoveries are similar to or higher than those by the Japanese standard method and by another modified oxygen electrode method. Concentrations of naturally occurring hydrogen peroxide in solid foods were < 0.87 microgram/g by the present method, lower than those by either the standard method or another modified oxygen electrode method.
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