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Inuzuka T, Hozumi I, Tamura A, Hiraiwa M, Tsuji S. Patterns of growth inhibitory factor (GIF) and glial fibrillary acidic protein relative level changes differ following left middle cerebral artery occlusion in rats. Brain Res 1996; 709:151-31. [PMID: 8869568 DOI: 10.1016/0006-8993(95)01444-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Growth inhibitory factor (GIF) has been identified as a new metallothionein-like protein, the level of which is decreased in the Alzheimer's disease brain. GIF and glial fibrillary acidic protein (GFAP) have been reported to be expressed in reactive astrocytes in the rat brain following stab wounds. Moreover, strong expression of GIF mRNA in reactive astrocytes after ventricular injection of kainic acid has been demonstrated. To clarify the biological functions of GIF and GFAP in repair of the CNS, we examined changes in their relative levels to sham control using a Western blotting technique in the rat left hemisphere following occlusion of the left middle cerebral artery, for 28 days after surgery. The GIF relative level declined to 56% of the sham-operated control value on day 7. Thereafter the GIF relative level increased and returned to the normal relative level by days 21-28. The GFAP relative level increased from day 3 and reached a maximum of 120% of the sham-operated control value on days 14-21. While GIF and GFAP were both detected in reactive astrocytes, an increase in the GFAP relative level occurred prior to an increase in GIF relative level following the ischemia. The patterns of changes in relative expression levels of GIF and GFAP were quite similar to those in our previous studies on effects of cerebral stab wounds in rats, although the changes were more rapid in the previous studies. GIF and GFAP appear to play different roles in the repair of the CNS. The present results also indicated that GIF could play an important role in CNS repair after cerebral ischemia and provide new insights into the mechanism of gliosis investigated mainly from the viewpoint of GFAP.
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Urakami H, Tamura A. [Symbiotic relationship between Orientia tsutsugamushi and vector mites]. Nihon Saikingaku Zasshi 1996; 51:497-511. [PMID: 8752375 DOI: 10.3412/jsb.51.497] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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328
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Tomitaka S, Sakamoto K, Tamura A, Kojima I, Fujita H. Dexamethasone suppression test by measuring spot urinary free cortisol in depression. Biol Psychiatry 1996; 39:220-2. [PMID: 8837985 DOI: 10.1016/0006-3223(95)00375-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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329
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Morimoto T, Ide T, Ihara Y, Tamura A, Kirino T. Transient ischemia depletes free ubiquitin in the gerbil hippocampal CA1 neurons. THE AMERICAN JOURNAL OF PATHOLOGY 1996; 148:249-57. [PMID: 8546212 PMCID: PMC1861594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We investigated ubiquitin immunoreactivity in the post-ischemic gerbil hippocampus using a panel of ubiquitin antibodies. Immunostaining for ubiquitin in the hippocampus was strongly dependent on the antibodies used. With rabbit polyclonal antibody U-5379, immunoreactivity disappeared from the hippocampus in the early reperfusion period and reappeared in the dentate granule cells and CA3 pyramidal cells but never in the CA1 pyramidal cells. In contrast, rat monoclonal antibody DF2 and mouse monoclonal antibody MAB1510 showed sustained immunoreactivity in the CA1 during the 48-hour reperfusion period. On the immunoblots of gerbil brain homogenates, three antibodies, U-5379, DF2 and MAB1510, exhibited similar specificities; all three labeled free ubiquitin most strongly. Immunoprecipitation disclosed that, under nondenaturing conditions, U-5379 bound exclusively free ubiquitin, whereas DF2 and MAB1510 had little affinity for free ubiquitin but appeared to have more affinity for conjugated ubiquitin. Immunoabsorption of these antibodies with free ubiquitin confirmed the above result. It is most likely that U-5379 recognized free ubiquitin in the tissue, whereas DF2 and MAB1510 recognized preferentially conjugated ubiquitin. Thus, transient ischemia depletes free ubiquitin but not conjugated ubiquitin in the CA1. This depletion may be caused by impaired conversion from conjugated to free ubiquitin and/or failure of de novo ubiquitin synthesis.
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Yuasa T, Tamura A, Ogata T, Akatsuka T, Kamada H. Assessment and comparison of algorithms for in vivo ESR-CT imaging of bioradicals with L-band microwaves. FRONTIERS OF MEDICAL AND BIOLOGICAL ENGINEERING : THE INTERNATIONAL JOURNAL OF THE JAPAN SOCIETY OF MEDICAL ELECTRONICS AND BIOLOGICAL ENGINEERING 1996; 7:311-330. [PMID: 8956971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In ESR-CT imaging, it is much more difficult to obtain satisfactory images than in imaging with other modalities, since two inverse problems, i.e. deconvolution of observed data and reconstruction from projections, must be solved. In this work, suitable algorithms for ESR-CT are examined using simulations and experiments. The algorithms were applied to actual data from a rat's head and a satisfactory reconstructed image was obtained from the viewpoint of morphological imaging. Several properties of the algorithms are discussed: (1) which combination of deconvolution and reconstruction method is favorable, (2) whether or not a raw differential signal should be integrated before deconvolution and reconstruction procedures, and (3) how SIRT, which offers good performance in ESR-CT, depends on an initial value and a noise type.
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Tamura A, Ohnishi K, Ishikawa O, Miyachi Y. Flow cytometric DNA content analysis on squamous cell carcinomas according to the preceding lesions. Br J Dermatol 1996; 134:40-3. [PMID: 8745884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
DNA-ploidy in primary cutaneous squamous cell carcinomas which had developed from different preceding clinical lesions was examined by flow cytometry using paraffin-embedded blocks. DNA-aneuploidy was detected in none of 15 squamous cell carcinomas arising from a burn scar. On the other hand, 12 of 26 squamous cell carcinomas arising from sun-damaged skin in the elderly, and two of four arising from chronic radiodermatitis, showed aneuploid patterns. A significantly higher incidence of DNA-aneuploidy was observed in squamous cell carcinomas arising from sun-damaged skin than those from a burn scar (P < 0.01); the mean diameter size of the former was significantly smaller than that of the latter (P < 0.0001). The mean age of patients with aneuploid tumours (74.2 +/- 9.2: years +/- standard deviation (SD)) was significantly higher than that with diploid tumours (64.1 +/- 13.8) (P < 0.01).
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Tamura A, Matsushita M, Naito A, Kojima S, Miura KI, Akasaka K. Dynamics of the three methionyl side chains of Streptomyces subtilisin inhibitor. Deuterium NMR studies in solution and in the solid state. Protein Sci 1996; 5:127-39. [PMID: 8771205 PMCID: PMC2143239 DOI: 10.1002/pro.5560050116] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Streptomyces subtilisin inhibitor (SSI) contains three methionine residues in a subunit: two (at positions 73 and 70) in the crucial enzyme-recognition sites P1 and P4, respectively, and one (Met 103) in the hydrophobic core. The motions of the side chains of these three Met residues and the changes in mobility on binding with subtilisin were studied by deuterium NMR spectroscopy in solution and in crystalline and powder solids. For this purpose, the wild-type SSI was deuterium-labeled at the methyl groups of all three Met residues, and three artificial mutant proteins were labeled at only one specific Met methyl group each. In solution, for methionines 73 and 70, the effective correlation times were only 0.8-1.0 x 10(-10)s indicating that the two side chains on the surface fluctuate almost freely. On formation of a complex with subtilisin, however, these high mobilities were quenched, giving a correlation time of 1.1 x 10(-8)s for the side chains of methionines 70 and 73. The correlation time of Met 103, located in the hydrophobic core, was at least 1.0 x 10(-8)s in free SSI, showing that its side chain motion is highly restricted. The nature of the internal motions of the three Met side chains was examined in more detail by deuterium NMR spectroscopy of powder and crystalline samples. The spectral patterns of the powder samples depended critically on hydration: immediately after lyophilization, the side-chain motions of the three Met residues were nearly quenched. With gradual hydration to 0.20 gram of water per gram protein-water, the orientational fluctuation of the methyl axes of methionines 70 and 73 was selectively enhanced in both amplitude and frequency (to about 1 MHz) and, at nearly saturating hydration (0.60 gram of water per gram protein-water), became extremely high in amplitude and frequency (> 10 MHz). In contrast, the polycrystalline wild-type SSI spectrum showed fine structures, reflecting characteristic motions of the Met side chains. The polycrystalline spectrum could be reproduced reasonably well by the same motion models and parameters used to simulate the powder spectrum at the final level of hydration, suggesting that the side-chain motions are similar in the fully hydrated powder and in crystals. Spin-lattice relaxation measurements gave evidence that, even in crystals, the methyl axes of all three Met residues undergo rapid motions with correlation times between 10(-8) and 10(-10)s, comparable to the correlation times in solution. Finally, in the hydrated stoichiometric complex of SSI with subtilisin BPN' in the solid state, large-amplitude motions are absent, but the side chains of methionines 70 and/or 73 are likely to have small-amplitude motions.
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Tamura A, Kataoka H, Nagase K, Mikuriya Y, Nasu M. Clinical significance of inferior ST elevation during acute anterior myocardial infarction. Heart 1995; 74:611-4. [PMID: 8541164 PMCID: PMC484115 DOI: 10.1136/hrt.74.6.611] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
OBJECTIVES To clarify the genesis and clinical significance of inferior ST elevation during acute anterior myocardial infarction. PATIENTS AND DESIGN A total of 106 patients with first acute anterior myocardial infarction (< or = 6 h) were divided into two groups according to the presence (group A, n = 12) or absence (group B, n = 94) of ST elevation of > or = 1 mm in at least two of the inferior leads on the admission electrocardiogram. RESULTS On admission electrocardiograms, group A had a smaller summed ST deviation in the lateral limb leads than group B. On emergency coronary arteriograms, the incidence of a wrapped left anterior descending artery was higher in group A than in group B (100% v 27%, P < 0.01). The incidence of occlusion of a left anterior descending artery distal to its first diagonal branch was higher in group A than in group B (100% v 46%, P < 0.01). Peak serum creatine kinase activity and in-hospital mortality tended to be lower in group A than in group B. Group A had better left ventricular ejection fraction and regional wall motion in the anterobasal and anterolateral regions in the chronic phase than group B. In contrast, regional wall motion in the diaphragmatic region was reduced to a greater extent in group A than in group B. CONCLUSIONS Inferior ST elevation during acute anterior myocardial infarction appears only in the presence of a combination of a lesser degree of transmural ischaemic myocardium in the anterobasal and anterolateral wall together with transmural ischaemic myocardium in the inferior wall; in all cases there was occlusion of a wrapped left anterior descending artery distal to its first diagonal branch. Patients with such an ST elevation appear to have a better in-hospital prognosis than those without it.
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Tamura S, Nelson H, Tamura A, Nelson N. Short external loops as potential substrate binding site of gamma-aminobutyric acid transporters. J Biol Chem 1995; 270:28712-5. [PMID: 7499392 DOI: 10.1074/jbc.270.48.28712] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
While the gamma-aminobutyric acid (GABA) transporter GAT1 exclusively transports GABA, GAT2, -3, and -4 also transport beta-alanine. Cross-mutations in the external loops IV, V, and VI among the various GABA transporters were performed by site-directed mutagenesis. The affinity of GABA transport as well as inhibitor sensitivity of the modified transporters was analyzed. Kinetic analysis revealed that a cross-mutation in which loop IV of GAT1 was modified to resemble GAT4 resulted in increased affinity to GABA from Km = 8.7 to 2.0 microM without changing the Vmax. A cross-mutation in loop VI, which swapped the amino acid sequence of GAT2 for GAT1, decreased the affinity to GABA (Km, 35 microM). These results suggest that loops IV and VI contribute to the binding affinity of GABA transporters. A substitution of three amino acids in loop V of GAT1 by the corresponding sequence of GAT3 resulted in beta-alanine sensitivity of its GABA uptake activity. These three amino acids in loop V seem to participate in the beta-alanine binding domain of GAT3. It is suggested that those three external loops (IV, V, and VI) form a pocket in which the substrate binds to the GABA transporters.
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Tamura A, Kataoka H, Mikuriya Y, Nasu M. Inferior ST segment depression as a useful marker for identifying proximal left anterior descending artery occlusion during acute anterior myocardial infarction. Eur Heart J 1995; 16:1795-9. [PMID: 8682009 DOI: 10.1093/oxfordjournals.eurheartj.a060830] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
To determine whether or not ST segment deviation on admission electrocardiograms can identify patients with anterior acute myocardial infarction due to proximal left anterior descending artery occlusion, the magnitude and location of ST segment elevation or depression were compared between patients with proximal left anterior descending artery occlusion (group A, n = 47) and those with distal left anterior descending artery occlusion (group B, n = 59). ST segment depression in each of the inferior leads was significantly greater in group A than in group B. The incidence of ST segment depression > or = 1 mm in each of the inferior leads (II; 81% vs 27%, III; 85% vs 54%, aVF; 87% vs 47%, P < 0.01) was significantly higher in group A than in group B. In addition, the incidence of ST segment depression > or = 1 mm in all of the inferior leads was significantly greater in group A than in group B (77% vs 22%, P < 0.01). In group A, maximal ST segment elevation was more frequent in lead V2 alone (43% vs 14%, P < 0.01). Group A had greater ST segment elevation in lead aVL than group B, and the incidence of ST segment elevation > or = 1 mm in lead aVL was significantly higher in group A than in group B (66% vs 47%, P < 0.05). ST segment depression > or = 1 mm in all of the inferior leads was most valuable for identifying group A patients (77% sensitivity and 78% specificity). In contrast, the maximal ST segment elevation in lead V2 alone or ST segment elevation > or = 1 mm in lead aVL had a low diagnostic value (43% sensitivity and 86% specificity, 66% sensitivity and 53% specificity, respectively). In conclusion, this study indicates that analysis of ST segment deviation in the inferior leads is useful for identifying patients with acute anterior myocardial infarction due to proximal left anterior descending occlusion.
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Yamada H, Hori H, Tanaka T, Fujita S, Fukuta-Ohi H, Hojo S, Tamura A, Shimizu T, Matsumura K. Secretion of laminin alpha 2 chain in cerebrospinal fluid. FEBS Lett 1995; 376:37-40. [PMID: 8521961 DOI: 10.1016/0014-5793(95)01240-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The absence of laminin alpha 2 chain causes muscle cell degeneration and peripheral dysmyelination in congenital muscular dystrophy patients and dy mice, suggesting its role in the maintenance of sarcolemmal architecture and peripheral myelinogenesis. Here we demonstrate the secretion of laminin alpha 2 chain in cerebrospinal fluid (CSF). Laminin alpha 2 chain was detected as a minor component of the total CSF proteins or glycoproteins. Laminin alpha 2 chain was localized in the cytoplasm of epithelial cells of choroid plexus, suggesting active secretion. Our results suggest that immunochemical analysis of CSF laminin alpha 2 chain could be useful as an aid for the diagnosis of congenital muscular dystrophy.
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Yamasaki S, Kusachi S, Moritani H, Kondo J, Hirohata S, Tamura A, Tsuji T. Reperfusion hastens appearance and extent of distribution of type I collagen in infarct zone: immunohistochemical study in rat experimental infarction. Cardiovasc Res 1995. [DOI: 10.1016/s0008-6363(95)00116-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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338
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Tamura A, Kitagawa M, Komatsu H, Takano R, Wakimoto J, Homma J, Nagase A, Nemoto E, Yanai N. Does an Epstein-Barr viral infection influence the pathogenesis of a primary pulmonary B-cell lymphoma? Lung 1995; 173:385-7. [PMID: 8531501 DOI: 10.1007/bf00172145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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339
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Abstract
Two patients with a scleroderma-like disorder induced by epoxy resins were reported from the Department of Dermatology, Gunma University School of Medicine, Japan in 1980. Here, we describe the clinical and laboratory characteristics of these patients after 17 years' follow-up from 1976 to 1993. Their systemic manifestations and indurated sclerotic skin changes disappeared within 5 years. No internal organ involvement has developed during the period of follow-up. On routine laboratory tests, no abnormalities have been found in the peripheral blood or in the blood chemistry or serology. Histological examination revealed atrophy of the dermis and restoration of the normal pattern of fine collagen bundles, when compared with the previous skin biopsy specimens. This scleroderma-like disorder induced by epoxy resins is considered to be different from systemic sclerosis: it has an acute onset and a fairly good prognosis, and does not show involvement of the internal organs.
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Yamasaki S, Kusachi S, Moritani H, Kondo J, Hirohata S, Tamura A, Tsuji T. Reperfusion hastens appearance and extent of distribution of type I collagen in infarct zone: immunohistochemical study in rat experimental infarction. Cardiovasc Res 1995; 30:763-8. [PMID: 8595624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND The effects of reperfusion on time-dependent alteration of type I collagen have not been examined. OBJECTIVES We compared the sequential changes in the appearance and distribution of type I collagen in reperfused infarct rat hearts to those in non-reperfused hearts. METHODS Using an experimental rat model of infarction, we performed immunohistochemical staining with a polyclonal antibody to type I collagen by the avidin-biotin-peroxidase method. Reperfusion was established after 2-h coronary ligation that produced complete necrosis of myocytes. RESULTS In reperfused hearts, type I collagen appeared in the peripheral zone of the infarct at day 2, which was 1 day earlier than in non-reperfused hearts. The extent of distribution of type I collagen in reperfused hearts was comparable to that observed approximately 1 day later in non-reperfused hearts. CONCLUSION Reperfusion can accelerate collagen matrix formation compared with that in non-reperfused hearts after acute myocardial infarction.
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Tamura A. Standard 12-lead electrocardiographic diagnosis for identifying the culprit artery in inferior wall acute myocardial infarction showing ST segment elevation in the inferior leads. Eur Heart J 1995; 16:1453. [PMID: 8881829 DOI: 10.1093/oxfordjournals.eurheartj.a060758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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342
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Shiomi M, Ito T, Tsukada T, Yata T, Watanabe Y, Tsujita Y, Fukami M, Fukushige J, Hosokawa T, Tamura A. Reduction of serum cholesterol levels alters lesional composition of atherosclerotic plaques. Effect of pravastatin sodium on atherosclerosis in mature WHHL rabbits. Arterioscler Thromb Vasc Biol 1995; 15:1938-44. [PMID: 7583574 DOI: 10.1161/01.atv.15.11.1938] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We examined whether serum cholesterol reduction alters the lesional composition of atherosclerotic plaques. To reduce serum cholesterol levels, we gave pravastatin sodium, a 3-hydroxy-3-methylglutaryl Coenzyme A reductase inhibitor, to mature Watanabe heritable hyperlipidemic rabbits, an LDL receptor-deficient animal model, for 48 weeks. Atherosclerotic lesions were immunohistochemically and conventionally stained and each lesional component area was measured by a color image analyzer. Compared with those of a placebo group, serum LDL cholesterol levels were reduced by 22% (P<.05). Data for atherosclerosis indicated a significant decrease in percent of surface lesion area (26% reduction) and in intimal thickening (30% reduction) in the abdominal aorta, as well as in coronary stenosis (29% reduction). Data for lesional composition indicated a significant decrease in the percent area of macrophage plus extracellular lipid deposits in aortic lesions (32% reduction) and coronary lesions (45% reduction). A significant increase was observed in the percent area of collagen in aortic lesions and in the percent area of smooth muscle cells in coronary lesions. The plaques seemed to become stable lesions as a result of pravastatin treatment. In conclusion, a long-term reduction of serum LDL cholesterol reduced lipid-related lesional components, in addition to suppressing the progression of established atherosclerosis.
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Okada M, Nakanishi H, Tamura A, Urae A, Mine K, Yamamoto K, Fujiwara M. Long-term spatial cognitive impairment after middle cerebral artery occlusion in rats: no involvement of the hippocampus. J Cereb Blood Flow Metab 1995; 15:1012-21. [PMID: 7593333 DOI: 10.1038/jcbfm.1995.127] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The behavioral and neurochemical changes in the chronic phase of permanent occlusion of the right middle cerebral artery (MCA) in rats were investigated. One month after MCA occlusion, 23 rats were unable to solve a radial eight-arm maze task during an entire 1-month period, whereas seven rats were able to solve this task. Three months after occlusion, 19 MCA-occluded rats failed to solve the task successfully again for at least 1 month (the cognitively impaired rats), whereas 11 MCA-occluded rats were able to solve it (the cognitively unimpaired rats). The rats that underwent behavioral testing were examined for any changes in the acetylcholine (ACh) levels in the hippocampus using HPLC with electrochemical detection or the formation of long-term potentiation (LTP) in the population spike of the hippocampal CA1 field. The immunohistochemical distribution of either the microtubule-associated protein 2 (MAP2) or glial fibrillary acidic protein (GFAP) in the hippocampus of the cognitively impaired rats was also studied. In the cognitively impaired rats, neither the suppression of the induction of LTP, nor the degradation of MAP2, nor the increase in the GFAP immunoreactivity was observed in the hippocampus. The levels of ACh in the hippocampus did not change significantly among the cognitively impaired, unimpaired, and the sham-operated rats. These results suggest that MCA occlusion is capable of producing long-term spatial cognitive disturbance in rats without any evidence of neurobiological damage in the hippocampus.
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Tomitaka S, Hashimoto K, Narita N, Minabe Y, Tamura A. Amantadine induces c-fos in rat striatum: reversal with dopamine D1 and NMDA receptor antagonists. Eur J Pharmacol 1995; 285:207-11. [PMID: 8566141 DOI: 10.1016/0014-2999(95)00504-e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Amantadine (1-aminoadamantane) induced Fos expression in the central, dorsal-medial and ventral-medial part of the striatum. The distribution pattern of Fos induced by amantadine was more similar to those seen with dopaminomimetics than with N-methyl-D-aspartate (NMDA) receptor antagonists. Pretreatment with the dopamine D1 receptor antagonist, SCH23390, and the NMDA receptor antagonist, MK-801, blocked amantadine induction of Fos in the striatum. However, amantadine induction of Fos in the striatum was unaffected by the dopamine D2 receptor antagonist, sulpiride. These results suggest that amantadine induction of Fos in the rat striatum is related to dopamine D1 and NMDA receptors.
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345
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Tamura A, Watanabe T, Mikuriya Y, Nasu M. Serum lipoprotein(a) concentrations are related to coronary disease progression without new myocardial infarction. Heart 1995; 74:365-9. [PMID: 7488447 PMCID: PMC484039 DOI: 10.1136/hrt.74.4.365] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
OBJECTIVE To examine the association between serum lipoprotein(a) and angiographically assessed coronary artery disease progression without new myocardial infarction. PATIENTS AND DESIGN 85 patients with coronary artery disease who underwent serial angiography with an interval of at least two years were studied. Progression of coronary artery disease was defined as an increase in diameter stenosis of 15% or more. Vessels on which angioplasty had been performed were excluded from the analysis. The patients were classified into two groups: a progression group without new myocardial infarction (n = 48) and non-progression group (n = 37). Risk factors including lipoprotein(a) were evaluated to see how they were related to progression without myocardial infarction. RESULTS There were no differences between the two groups in the following factors: age, gender, the time interval between the angiographic studies, the distribution of the analysed coronary arteries, and history of well established coronary risk factors. Univariate analysis showed that serum lipoprotein(a) (P = 0.0002), cigarette smoking between the studies (P = 0.002), serum high density lipoprotein (P = 0.003), and serum low density lipoprotein (P = 0.01) were related to progression without myocardial infarction. Multivariate analysis selected two independent factors for progression without myocardial infarction: serum lipoprotein(a) (P = 0.003) and serum high density lipoprotein (P = 0.03). CONCLUSIONS Serum lipoprotein(a) concentrations are closely related to the progression of coronary artery disease without new myocardial infarction. Lipoprotein(a) lowering treatment may be needed to prevent disease progression in patients with coronary artery disease and high serum lipoprotein(a).
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Tamura A, Mikuriya Y, Kataoka H, Nagase K, Nasu M. Emergent coronary angiographic findings of patients with ST depression in the inferior or lateral leads, or both, during anterior wall acute myocardial infarction. Am J Cardiol 1995; 76:516-7. [PMID: 7653456 DOI: 10.1016/s0002-9149(99)80142-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In conclusion, the present study indicates that there are several distinctive differences in emergent coronary angiographic findings according to the presence or absence of ST depression in the inferior or lateral leads, or both, and location of the leads showing ST depression on admission electrocardiograms in patients with anterior AMI. The coronary angiographic features of patients with this ECG finding greatly support a poor prognosis. In patients with anterior AMI, analysis of ST depression on an admission electrocardiogram should be routinely performed because it is useful in predicting coronary anatomy, the extent of infarction, and its prognosis.
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Takada S, Tamura A, Hiraoka K, Ogino M, Mori H, Imamura T. [A case of remission of recurrent carcinosarcoma of the uterus with massive ascites by carboplatin]. Gan To Kagaku Ryoho 1995; 22:1253-6. [PMID: 7661577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A case of remission of recurrent carcinosarcoma of the uterus with massive ascites by chemotherapy using carboplatin (CBDCA) is reported. A 75-year-old female was diagnosed with cancer of the uterine body. She underwent abdominal total hysterectomy with bilateral salpingo-oophorectomy, which revealed carcinosarcoma of the uterus penetrating the myometrium and reaching the serosa of the uterus. Eight weeks after, she developed abdominal distension, obstruction of bilateral ureters and bleeding tumor measuring 5 cm in diameter at the vaginal cuff ending. Acute retention of bloody ascites of more than 2500 ml was demonstrated. Abdominal centesis, aspiration of ascites and intraperitoneal administration of 600 mg of CBDCA were performed. Two weeks after single use of CBDCA, the ascites completely disappeared and there was recovery from anuria. The remission has lasted more than 4 months, which has suggested the efficacy of CBDCA for uterine carcinosarcoma.
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Kubota M, Tomukai N, Kitahara S, Nakagomi T, Tamura A, Hisaki H, Shimasaki H, Ueta N. [Sphingolipid changes in rat cerebral cortex during focal ischemia--how does ceramide accumulate in an ischemic condition?]. NO TO SHINKEI = BRAIN AND NERVE 1995; 47:756-61. [PMID: 7546920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Levels of ceramide, sphingomyelin, cerebroside and gangliosides were determined in rat cerebral cortex during focal ischemia produced by middle cerebral artery occlusion. Ceramide began to increase at 6 hours of ischemia and increased to 4.5 folds at 96 hours. Amino-linked fatty acids in increased ceramide were composed solely of non-hydroxy fatty acids, and stearic acid was the most prominent. Sphingomyelin, whose amino-linked fatty acids were mostly stearic acid, decreased in a time-dependent manner and became about a half of controls at 96 hours. Hydroxy fatty acid linked cerebroside decreased at and after 6 hours of ischemia, whereas significant decrease of non-hydroxy fatty acid linked cerebroside occurred only at 96 hours of ischemia. There were no measurable changes in the levels of gangliosides. The results suggested that ceramide was produced in the cerebral cortex by the breakdown of sphingomyelin during ischemia.
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349
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Tamura A, Komatsu H, Yanai N, Homma J, Nagase A, Nemoto E, Hirai T, Hashizume T, Kawata K, Ishikawa S. Primary pulmonary lymphoma: relationship between clinical features and pathologic findings in 24 cases. The Japan National Chest Hospital Study Group for Lung Cancer. Jpn J Clin Oncol 1995; 25:140-52. [PMID: 7666590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
To elucidate the relationship between the clinical features and pathologic findings of primary pulmonary lymphoma, we reviewed 24 patients with this disease. The pulmonary lymphomas were divided into four groups: (1) B-cell lymphoma composed of small to medium-sized lymphoid cells (19 cases); (2) B-cell lymphoma composed of large lymphoid cells (three cases); (3) T-cell lymphoma (one case); (4) malignant lymphoma of lymphomatoid granulomatosis (LYG) type (one case). Radiographs of the first group revealed a predominance of infiltration associated with ill-defined tumor margins upon gross pathology, corresponding histologically to lymphangitic spread. Air bronchogram and pleural tail or abutment were additional radiographic features. Characteristics of the second group were a nodule or mass evident on radiographs and well-circumscribed tumor margins upon gross pathology. Lack of air bronchogram was an another radiographic feature in this group. Seventeen patients in these two groups underwent complete resection of the tumors and survived without recurrence, whereas four received chemotherapy after biopsy and survived with disease. These results indicate that primary pulmonary B-cell lymphoma is a low-grade malignancy and that complete resection is the only therapy which leads to cure. In a single patient with T-cell lymphoma, the radiographic and pathologic features of the tumor were indistinguishable from those in the first group, but the patient had an unfavorable prognosis. We consider that, from a prognostic viewpoint, it is important to determine the T- or B-immunophenotype of the tumor cells for diagnosis of primary pulmonary lymphoma. The only patient in this series with pulmonary lymphoma of LYG type showed distinctive clinicopathologic findings. We consider that this uncommon disease should be separated from other types of primary pulmonary lymphoma.
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350
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Kawai K, Aoki M, Nakayama H, Kobayashi K, Sano K, Tamura A. Posterior pituitary hematoma in a case of posttraumatic diabetes insipidus. Case report. J Neurosurg 1995; 83:368-71. [PMID: 7616288 DOI: 10.3171/jns.1995.83.2.0368] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A 28-year-old man presented with diabetes insipidus (DI) 10 days after basilar skull fracture without brain injury. Magnetic resonance (MR) imaging revealed a hematoma in the posterior lobe of the pituitary gland but no lesions in the hypothalamus or pituitary stalk. The patient's DI continued for 2 months at which time transsphenoidal surgery was performed to decompress the cystic hematoma with persistent mass effect. The DI attenuated shortly after the surgery and the patient became completely free from DI 5 months later. Although hemorrhage into the posterior lobe is one of the frequent pathological changes in fatal head-injury victims and secondary DI in these cases has usually been thought to be acute and transient, the true incidence and natural course of the posterior pituitary hemorrhage and subsequent DI in nonfatal head-injury patients are totally unknown. In this article, the authors present the first demonstration on MR imaging of a posterior pituitary hematoma in a patient with head injury. The authors propose that serial MR imaging is an important diagnostic tool in patients with posttraumatic DI because some of them may harbor pituitary hematoma and because decompression surgery may prevent transition to permanent DI, especially in cases when the mass effect is persistent due to a cystic change in the hematoma.
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