401
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Yonemori K, Imamura T, Ishidou Y, Okano T, Matsunaga S, Yoshida H, Kato M, Sampath TK, Miyazono K, ten Dijke P, Sakou T. Bone morphogenetic protein receptors and activin receptors are highly expressed in ossified ligament tissues of patients with ossification of the posterior longitudinal ligament. THE AMERICAN JOURNAL OF PATHOLOGY 1997; 150:1335-47. [PMID: 9094990 PMCID: PMC1858169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Ossification of the posterior longitudinal ligament (OPLL) is a pathological ossification in the spinal ligament, with formation of ectopic bone mainly through endochondral ossification. Bone morphogenetic proteins (BMPs) and activins are multifunctional proteins that belong to the transforming growth factor-beta superfamily and that have been implicated in the formation of new bone and cartilage. BMPs and activins signal via type I and type II receptors for BMPs (BMPRs) and activins (ActRs), respectively. OP-1/BMP-7 binds to BMPR-II and ActR-II and forms complexes with BMPR-IA and -IB and ActR-I. We studied the expression of BMPR-IA, -IB, and -II, ActR-I, ActR-II, and OP-1/BMP-7 by immunohistochemistry in ossified ligament tissues of patients with OPLL and control ligament tissues from patients with cervical disc herniation. The expression of BMPRs and ActRs was elevated in OPLL compared with controls. Expressions of BMPR-IA, -IB, and -II were observed not only in chondrocytes at the fibrocartilage tissue around the calcified zone but also in fibroblast-like spindle cells at the nonossified ligament. ActR-I and -II were found co-localized in the hypertrophic chondrocytes near the calcified zone and in the ossified tissue. OP-1/BMP-7 was expressed in chondrocytes near the calcified zone. In the control cases, the BMPRs and ActRs were only weakly expressed in the fibrocartilage tissue at the site of ligament attachments to bone and OP-1/BMP-7 was not detected. Enhanced expression of BMPRs at the nonossified ligament in OPLL patients suggests that these cells have a greater potential to differentiate into osteogenic cells than ligament cells from non-OPLL patients. The high expression of BMPRs and ActRs in the ectopic ossified ligament suggests that BMPs and activin may be tightly involved in the pathological ossification process of OPLL.
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402
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Ito S, Kudo K, Imamura T, Jitsufuchi N, Kimura K. Detection of drugs and poisons in postmortem tissues--determination of paraquat in tissues of rabbits buried underground. NIHON HOIGAKU ZASSHI = THE JAPANESE JOURNAL OF LEGAL MEDICINE 1997; 51:83-8. [PMID: 9184018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The possibility of detecting paraquat in tissues of rabbits buried underground over a 2-year period was examined. Paraquat (1.2 g) was given orally to rabbits, which were sacrificed 1 h after administration. The animals were buried underground, and the skeletal muscles and the bones were collected 3 and 6 months after death, and 3, 6, 12, and 24 months after death, respectively. Paraquat was present in all bone marrow samples, showing a slight decrease in concentration until 12 months. Paraquat was also detected in all skeletal muscle samples, showing almost no change in concentration until 6 months. These results indicate that intoxication with paraquat as well as the degree of poisoning can both be determined from the skeletal muscles and bone marrow of cadavers which have been buried underground for a long period of time even in human cases.
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403
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Tokunaga H, Kudo K, Jitsufuchi N, Ohtsuka Y, Imamura T. Sensitive determination of sulpiride in human plasma by high-performance liquid chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1997; 691:203-7. [PMID: 9140776 DOI: 10.1016/s0378-4347(96)00428-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We developed a simple, sensitive and reliable method for the determination of sulpiride, a specific antipsychotic drug, in human plasma using high-performance liquid chromatography. A structurally related benzamide, tiapride, was used as the internal standard. A Sep-Pak C18 cartridge was used to extract a sample from 1 ml of plasma. The extract was dissolved in methylene chloride, and then back-extracted with 0.01 M hydrochloric acid. The aqueous layer was put on a octadecylsilica column with a mobile phase of 50% acetonitrile in 0.01 M phosphate buffer (pH 3.0). A fluorescence detector with excitation at 300 nm and emission at 365 nm was used for detection. The calibration curve was linear in the concentration range of 10-1500 ng/ml, and the lower limit of detection was 1 ng/ml. We used this method to examine plasma levels of sulpiride in 14 inpatients being treated with sulpiride for 6 months. The determined plasma levels were 70.1-1121.2 ng/ml, and the correlation between daily dose and plasma concentration was positive. This simple, reliable method is expected to be put to good use in forensic and hospital laboratories.
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404
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Imamura T, Rudich Y, Talukdar RK, Fox RW, Ravishankara AR. Uptake of NO3 on Water Solutions: Rate Coefficients for Reactions of NO3 with Cloud Water Constituents. J Phys Chem A 1997. [DOI: 10.1021/jp962787e] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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405
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Jitsufuchi N, Kudo K, Tokunaga H, Imamura T. Selective determination of sultopride in human plasma using high-performance liquid chromatography with ultraviolet detection and particle beam mass spectrometry. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1997; 690:153-9. [PMID: 9106039 DOI: 10.1016/s0378-4347(96)00423-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We developed a sensitive and selective method for determining levels of sultopride, a neuroleptic drug of the substituted benzamide, in human plasma using high-performance liquid chromatography (HPLC) combined with UV detection and particle beam mass spectrometry (PBMS). Sultopride was extracted with tert.-butylmethyl ether using a salting-out technique. Tiapride served as an internal standard (I.S.). Sultopride and I.S. were separated by HPLC on a silica column with a mobile phase of acetonitrile-0.1 M ammonium acetate (94:6, v/v). The calibration curves were linear over the concentration range from 5 to 1000 ng/ml by HPLC with UV detection and from 10 to 1000 ng/ml with PBMS detection. The limit of quantitation was 5 ng/ml with UV detection and 10 ng/ml with PBMS detection. The absolute recovery was 92% and the within-day coefficients of variation were 2.9-7.1% at plasma concentrations from 50 to 500 ng/ml, determined by HPLC with UV detection. Using this method, we measured the plasma concentrations of sultopride with replicate analyses in four hospitalized patients and steady-state plasma levels were determined to be 161.6 +/- 30.8, 321.1 +/- 93.7, 726.5 +/- 143.1 and 1273.6 +/- 211.2 ng/ml, respectively.
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406
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Hirono N, Mori E, Ikejiri Y, Imamura T, Shimomura T, Hashimoto M, Yamashita H, Ikeda M. [Japanese version of the Neuropsychiatric Inventory--a scoring system for neuropsychiatric disturbance in dementia patients]. NO TO SHINKEI = BRAIN AND NERVE 1997; 49:266-71. [PMID: 9125732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND PURPOSE Neuropsychiatric disturbances are common and burdensome symptoms of dementias. Assessment and measurement of neuropsychiatric disturbances are indispensable to the management of patients with dementia and for clinical research. No standardized instruments have been developed for these purposes in Japan. The Neuropsychiatric Inventory (NPI), developed by Cummings et al., is a standardized, validated, and reliable tool to assess a wide range of neuropsychiatric derangements in patients with dementia, and has been used in clinical studies in North America. In this study, we prepared a Japanese version of the NPI and tested its reliability and usefulness in dementia patients. SUBJECTS AND METHODS The subjects were 174 patients with dementia, including Alzheimer's disease (140), frontotemporal dementia (12), vascular dementia (19), and normal pressure hydrocephalus (3), whose diagnosis was made on the basis of the results of extensive examinations including MRI and PET/SPECT of the brain and appropriate clinical diagnostic criteria for each disorder. The subjects consisted of 133 women and 41 men; their mean age was 72.6 +/- 7.7 years (S.D.; range: 49 to 88) years. An examiner (neurologist) used the NPI to interview a caregiver familiar with the patient's everyday behavior. In 24 randomly selected patients interview was repeated by another examiner (psychiatrist) one month later, and test-retest reliability was evaluated. The Clinical Dementia Rating (CDR), the Mini-Mental State Examination (MMSE), and the Alzheimer's Disease Assessment Scale (ADAS) were used to assess the severity of the dementia and cognitive impairment. RESULTS The MMSE scores ranged from 5 to 29 (mean +/- SD = 19.0 +/- 4.8) and the ADAS scores ranged from 7 to 63 (24.3 +/- 10.9). The CDR score was 0.5 in 17 patients, 1 in 95 patients, 2 in 52 patients, and 3 in 10 patient. Test-retest reliability of each score was acceptably high, and the correlation coefficient for each score obtained by repeated assessments in this study was similar to the coefficient in the original report. Apathy was the most common behavior in the ten abnormal behavioral domains, and euphoria was the least common. The prevalence of abnormal findings was also comparable to the results in the original report. The total NPI scores and many of the NPI subscale scores were significantly correlated with both the severity of dementia and cognitive impairment. CONCLUSIONS This Japanese version of NPI, whose reliability and competency are comparable to those of the original version, is a reliable and useful tool for measuring neuropsychiatric disturbances in dementia patients.
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407
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Kitagaki H, Mori E, Hirono N, Ikejiri Y, Ishii K, Imamura T, Ikeda M, Yamaji S, Yamashita H, Shimomura T, Nakagawa Y. Alteration of white matter MR signal intensity in frontotemporal dementia. AJNR Am J Neuroradiol 1997; 18:367-78. [PMID: 9111678 PMCID: PMC8338562] [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
PURPOSE To determine the diagnostic potential of MR imaging to show white matter involvement in frontotemporal dementia. METHODS We evaluated MR signal intensity in cerebral white matter by visually inspecting and by quantitatively measuring signal intensity on MR images in 22 patients with frontotemporal dementia. The findings were compared with those in 22 age- and sex-matched patients who had had Alzheimer disease for the same length of time and with 16 age- and sex-matched healthy control subjects. RESULTS Patients with frontotemporal dementia had a significant increase in white matter signal intensity in the frontal and/or temporal lobes on T2- and proton density-weighted images. Visual inspection of regular proton density-weighted images and measurements made on the T2- and proton density-weighted images were sensitive to changes in white matter signal. CONCLUSION Increased MR signal intensity in the frontotemporal white matter on T2- and proton density-weighted MR images is a useful diagnostic sign of frontotemporal dementia and distinguishes this condition from Alzheimer disease.
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408
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Imamura T, Tokunaga H, Ise H, Jitsufuchi N, Kudo K. Usefulness of elastica-van Gieson stain for the pathomorphological diagnosis of a cutaneous electric mark--a fatal electrocution case during arc welding. FUKUOKA IGAKU ZASSHI = HUKUOKA ACTA MEDICA 1997; 88:23-6. [PMID: 9071051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Identification of an electric mark on a body is required for a precise diagnosis of electrocution at the time of forensic autopsy. We applied Elastica-van Gieson (EVG) stain as a means of obtaining the pathomorphological diagnosis of a cutaneous electric mark in relation to a fatal electrocution case. Using EVG stain, the characteristic findings of electric marks, such as elongation of basal-cell nuclei and vacuolation of cells within the epidermis, were clearly observed, while in addition, disarrangement of elastic fibers in the connective tissues within the dermis was also demonstrated. EVG staining was considered to be useful in enabling pathomorphological observations of a cutaneous electric mark to be made.
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409
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Matsuda K, Yamaji S, Ishii K, Sasaki M, Sakamoto S, Kitagaki H, Imamura T, Mori E. Regional cerebral blood flow and oxygen metabolism in a patient with Korsakoff syndrome. Ann Nucl Med 1997; 11:33-5. [PMID: 9095320 DOI: 10.1007/bf03164755] [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: 02/04/2023]
Abstract
We report a functional neuroimaging study of a patient clinically diagnosed with Korsakoff syndrome. Positron emission tomography (PET) with the 15O inhalation method showed decreased regional cerebral blood flow (rCBF) and decreased regional cerebral metabolic ratio for oxygen (rCMRO2) in the bilateral fronto-temporal areas and in the left thalamus. These results suggest that dysfunction of the frontal-thalamic neural network plays a role in the disturbance of Korsakoff syndrome.
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410
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Nakao A, Röijer E, Imamura T, Souchelnytskyi S, Stenman G, Heldin CH, ten Dijke P. Identification of Smad2, a human Mad-related protein in the transforming growth factor beta signaling pathway. J Biol Chem 1997; 272:2896-900. [PMID: 9006934 DOI: 10.1074/jbc.272.5.2896] [Citation(s) in RCA: 132] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Transforming growth factor-beta (TGF-beta) superfamily members are multifunctional cytokines that exert their effects via heteromeric complexes of two distinct serine and threonine kinase receptors. Drosophila mothers against decapentaplegic and related genes in Caenorhabditis elegans, Xenopus, and mammals were shown to function downstream in the intracellular signaling pathways of TGF-beta superfamily members. Here we report the cloning of a Mad-related protein, termed Sma- and Mad-related protein 2 (Smad2). TGF-beta stimulated the phosphorylation and nuclear translocation of Smad2 in nontransfected Mv1Lu cells. In addition, we demonstrated that TGF-beta and activin mediated phosphorylation of Smad2 after its overexpression with appropriate type I and II receptors in COS cells. Smad2 and Smad1 were found to be broadly expressed in human tissues. Smad2 is closely linked to DPC4 on chromosome 18q21.1, a region often deleted in human cancers. Cells that lack Smad2 may escape from TGF-beta-mediated growth inhibition and promote cancer progression.
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411
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Etoh T, Kato J, Washimine H, Imamura T, Kitamura K, Koiwaya Y, Kangawa K, Eto T. Plasma proadrenomedullin N-terminal 20 peptide (PAMP) in patients with congestive heart failure. Horm Metab Res 1997; 29:46-7. [PMID: 9049655 DOI: 10.1055/s-2007-978980] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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412
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Mori E, Hirono N, Yamashita H, Imamura T, Ikejiri Y, Ikeda M, Kitagaki H, Shimomura T, Yoneda Y. Premorbid brain size as a determinant of reserve capacity against intellectual decline in Alzheimer's disease. Am J Psychiatry 1997; 154:18-24. [PMID: 8988953 DOI: 10.1176/ajp.154.1.18] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Both the magnitude of brain atrophy and premorbid brain size determine the volume of the brain affected by Alzheimer's disease. To examine the possibility that premorbid brain volume is a determinant of cognitive reserve in patients with Alzheimer's disease, the relation between diffuse brain atrophy and cognitive decline and the impact of premorbid brain size on cognitive decline were studied in patients with Alzheimer's disease. METHOD By measuring whole brain volume and intracranial volume in 60 patients with probable Alzheimer's disease, mild to moderate in severity, with the use of high-resolution magnetic resonance imaging and image processing, the authors studied the impact of premorbid brain volume and magnitude of diffuse brain atrophy on cognitive functions. On the basis of the normative brain-calvarium relationship derived from data an 28 healthy adults and the total intracranial volume measure of each patient, the magnitude of brain atrophy and premorbid brain volume were estimated. RESULTS After control for the effects of age, sex, and education as confounding factors, it was found that the Alzheimer's disease patients' intelligence was correlated both positively with premorbid brain volume and negatively with magnitude of brain atrophy, while impairments in language and memory were correlated with magnitude of brain atrophy but not with premorbid brain volume. CONCLUSIONS These findings partially support the hypothesis that premorbid brain volume is a determinant of reserves against intellectual decline in Alzheimer's disease.
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413
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Travis J, Pike R, Imamura T, Potempa J. Porphyromonas gingivalis proteinases as virulence factors in the development of periodontitis. J Periodontal Res 1997; 32:120-5. [PMID: 9085221 DOI: 10.1111/j.1600-0765.1997.tb01392.x] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Porphyromonas gingivalis contains exceedingly high concentrations of cysteine proteinases with trypsin-like activity which have been implicated as virulence factors in adult-onset periodontitis. These enzymes, referred to as gingipains, cleave protein and peptide substrates after arginine (gingipain R) and lysine residues (gingipain K), and it has been found that neither is easily inhibited by host proteinase inhibitors. Examination of the properties of each proteinase clearly indicates a role(s) for both in the dysregulation of a number of normally tightly controlled pathways. The effects of such uncontrolled proteolysis are the development of edema (kallikrein/kinin pathway activation by gingipain R), neutrophil infiltration (complement pathway activation by gingipain R), and bleeding (degradation of fibrinogen by gingipain K). Since three of the major hallmarks of periodontitis involve increased crevicular flow, neutrophil accumulation at infected sites and bleeding on probing, it seems likely that both P. gingivalis-derived proteinases are important virulence factors in the development of periodontal disease.
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414
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Hisatomi A, Kubota A, Ohashi M, Umeda F, Nawata H, Imamura T, Nagata T. Elevated L-kynurenine level and its normalization by prednisolone in a patient with eosinophilia-myalgia syndrome. FUKUOKA IGAKU ZASSHI = HUKUOKA ACTA MEDICA 1997; 88:11-7. [PMID: 9037890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We report a L-tryptophan-induced case of eosinophilia-myalgia syndrome in a Japanese woman and describe the time course of changes in tryptophan metabolism observed during steroid therapy. She had taken 1.0 g of the implicated L-tryptophan daily. When admitted due to painful swelling of her extremities, eosinophil count was 22.3 x 10(9)/L. Before prednisolone treatment, her serum L-kynurenine level was 10.2 mumol/L, a level about three-fold higher than the normal value, while serum tryptophan level was abnormally low (23.1 mumol/L). On the 14th day of prednisolone treatment (40 mg daily), L-kynurenine was declined to 8.1 mumol/L and, concomitantly, L-tryptophan level increased to the normal range (51.0 mumol/L). Subsequently, on the 42nd day of therapy, serum L-kynurenine was normalized. In contrast, serum serotonin level was unchanged throughout the course of this therapy. Prednisolone dramatically reduced the elevated serum L-kynurenine with a reciprocal increase in serum L-tryptophan indicates that abnormal tryptophan metabolism, may play a role in the pathogenesis of eosinophilia myalgia syndrome, and that the observed effect of steroid treatment was due to suppression of elevated activity of indoleamine 2, 3-dioxygenase, a first rate-limiting enzyme of the kynurenine pathway.
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415
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Kage S, Takekawa K, Kurosaki K, Imamura T, Kudo K. The usefulness of thiosulfate as an indicator of hydrogen sulfide poisoning: three cases. Int J Legal Med 1997; 110:220-2. [PMID: 9274948 DOI: 10.1007/s004140050071] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We examined the usefulness of thiosulfate as an indicator of hydrogen sulfide poisoning by analysing sulfide and thiosulfate in three cases. In the first (non-fatal) case sulfide and thiosulfate were not detected in the blood samples from any of the four workers involved in the accident. In the urine samples, only thiosulfate was detected in three out of the four workers at a concentration of 0.12-0.43 micromol/ml, which was 4-14 times higher than the level in a healthy person. In the second (fatal) case sulfide and thiosulfate were detected in the blood sample at concentrations of 0.007 micromol/ml for sulfide, and 0.025 micromol/ml for thiosulfate. The thiosulfate concentration was at least 8 times higher than the level in a healthy person. In the third (fatal) case sulfide and thiosulfate were detected in the blood sample at concentrations of 0.95 micromol/ml for sulfide, and 0.12 micromol/ml for thiosulfate. Based on the above results, we concluded that thiosulfate in urine is the only indicator to prove hydrogen sulfide poisoning in non-fatal cases, while the analysis of sulfide in fatal cases should be accompanied by the measurement of thiosulfate in blood.
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416
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Takata Y, Imamura T, Haruta T, Sasaoka T, Morioka H, Ishihara H, Sawa T, Usui I, Ishiki M, Kobayashi M. The dominant negative effect of a kinase-defective insulin receptor on insulin-like growth factor-I-stimulated signaling in Rat-1 fibroblasts. Metabolism 1996; 45:1474-82. [PMID: 8969279 DOI: 10.1016/s0026-0495(96)90175-4] [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: 02/03/2023]
Abstract
To study the interaction between insulin receptor (IR) and insulin-like growth factor-I (IGF-I) receptor (IGF-IR) tyrosine kinases, we examined IGF-I action in Rat-1 cells expressing a naturally occurring tyrosine kinase-deficient mutant IR (Asp 1048 IR). IGF-I normally stimulated receptor autophosphorylation, IRS-I phosphorylation, and glycogen synthesis in cells expressing Asp 1048 IR. However, the Asp 1048 IR inhibited IGF-I-stimulated thymidine uptake by 45% to 52% and amino acid uptake (aminoisobutyric acid [AIB]) by 58% in Asp 1048 IR cells. Furthermore, IGF-I-stimulated tyrosine kinase activity toward synthetic polymers, Shc phosphorylation, and mitogen-activated protein (MAP) kinase activity was inhibited. The inhibition of mitogenesis and AIB uptake was restored with the amelioration of the impaired tyrosine kinase activity and Shc phosphorylation by the introduction of abundant wild-type IGF-IR in Asp 1048 IR cells. These results suggest that the Asp 1048 IR causes a dominant negative effect on IGF-IR in transmitting signals to Shc and MAP kinase activation, which leads to decreased IGF-I-stimulated DNA synthesis, and that the kinase-defective insulin receptor does not affect IGF-I-stimulated IRS-I phosphorylation, which leads to the normal IGF-I-stimulated glycogen synthesis.
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417
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Hayashiba Y, Kimura K, Kashimura S, Nagata T, Imamura T. Identification of vegetable species in gastric contents using HPLC. Int J Legal Med 1996; 108:206-9. [PMID: 8652426 DOI: 10.1007/bf01369793] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Identification of 16 vegetables, focusing on the influence of digestion in the stomach, was carried out on the basis of the types of flavonoids detected on chromatograms using HPLC. Among the 12 vegetables for which flavonoids were detected, the chromatographic patterns of the flavonoids in digested vegetables were the same as those of the corresponding raw vegetables, making it possible to identify the species of vegetables even after digestion. In our analysis, 5 mg of a freeze-dried sample was found be an adequate quantity to enable the detection of flavonoids. Brief practical cases are also described.
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418
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Rydén M, Imamura T, Jörnvall H, Belluardo N, Neveu I, Trupp M, Okadome T, ten Dijke P, Ibáñez CF. A novel type I receptor serine-threonine kinase predominantly expressed in the adult central nervous system. J Biol Chem 1996; 271:30603-9. [PMID: 8940033 DOI: 10.1074/jbc.271.48.30603] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Receptor serine-threonine kinases (RSTK) mediate inhibitory as well as stimulatory signals for growth and differentiation by binding to members of the transforming growth factor-beta (TGF-beta) superfamily. Over 12 different RSTKs have been isolated so far, displaying wide expression in peripheral tissues and in the nervous system. Here we report the isolation and characterization of a novel type I RSTK termed activin receptor-like kinase-7 (ALK-7) that, unlike other members of this receptor family, is predominantly expressed in the adult central nervous system. The ALK-7 gene encodes a 55-kDa cell-surface protein that exhibits up to 78% amino acid sequence identity in the kinase domain to previously isolated type I receptors for TGF-beta and activin. In the extracellular domain, however, ALK-7 is more divergent, displaying comparable similarities with all members of the ALK subfamily. RNase protection and in situ hybridization studies demonstrated a highly specific mRNA distribution restricted to neurons in several regions of the adult rat central nervous system, including cerebellum, hippocampus, and nuclei of the brainstem. Receptor reconstitution and cross-linking experiments indicated that ALK-7 can form complexes with type II RSTKs for TGF-beta and activin in a ligand-dependent manner, although direct binding of ALK-7 to ligand in these complexes could not be demonstrated. The specific expression pattern of ALK-7, restricted to the postnatal central nervous system, indicates that this receptor may play an important role in the maturation and maintenance of several neuronal subpopulations.
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419
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Toyoda K, Imamura T, Saku Y, Oita J, Ibayashi S, Minematsu K, Yamaguchi T, Fujishima M. Medial medullary infarction: analyses of eleven patients. Neurology 1996; 47:1141-7. [PMID: 8909419 DOI: 10.1212/wnl.47.5.1141] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Of 2,130 consecutive patients admitted to two hospitals with acute brain infarction, we examined 11 patients (0.52%) with medial medullary infarction. The infarcts documented by MRI were unilateral in 9 patients and bilateral in 2 patients, and located in the anteromedial arterial territory of the upper or middle part of the medulla. Atherosclerosis of the vertebral arteries was the predominant vascular pathology. The vertebral artery was occluded at its terminal portion in 7 patients. Nine patients had hypertension, and 8 of these had additional risk factors. Male gender (10 patients) and smoking habits (7 patients) were more prevalent compared with patients with pontine infarction. One patient had a medial medullary infarction attributed to dissection of the vertebral arteries following blunt head injury. Limb weakness was the major symptom in all patients, and gaze-evoked nystagmus was also frequent (6 patients). Tongue weakness ipsilateral to the infarct, the classic sign of medial medullary syndrome, was evident in only 3 patients. The outcome was usually excellent.
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420
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Imamura T, Di Virgilio S, Bagarozzi DA, Matheson N, Travis J. Induction of histamine release from non-immunized guinea pigs: a possible involvement of lectin-like factor(s) in pollinosis. Int Arch Allergy Immunol 1996; 111:161-5. [PMID: 8859225 DOI: 10.1159/000237362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
To investigate nonimmune pathogenic functions of pollens, vascular permeability enhancement (VPE) activity of pollen extracts was examined using guinea pigs nonimmunized against pollens. Ryegrass, ragweed, mesquite and almond, but not common cattail and sumac, induced VPE which was inhibited primarily by an anti-histamine drug. Ryegrass pollen VPE activity was extracted more at pH 7.3 than at pH 6.5 or 8.0 and the maximal activity was extracted in 30 min. Interestingly, more than 60% of the maximal activity was extracted in 5 min. The maximal VPE activity had a dose-dependency similar to histamine (3 x 10(-5) M) but lasted longer than the histamine activity. The VPE activity was inhibited by oligomannose-glycosylated ovalbumin or avidin, as well as the oligosaccharides but not by the deglycosylated proteins. These results indicate that some pollens contain lectin-like, histamine-releasing factor(s), which may be involved in part in pollinosis, by inducing mast cell degranulation through a nonimmune mechanism and resulting in allergy-like symptoms.
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Sasaoka T, Ishiki M, Sawa T, Ishihara H, Takata Y, Imamura T, Usui I, Olefsky JM, Kobayashi M. Comparison of the insulin and insulin-like growth factor 1 mitogenic intracellular signaling pathways. Endocrinology 1996; 137:4427-34. [PMID: 8828504 DOI: 10.1210/endo.137.10.8828504] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We compared the intracellular insulin-like growth factor-1 (IGF-1) and insulin signaling pathways in Rat1 fibroblasts expressing the equivalent number of insulin receptors and endogenous IGF-1 receptors. Insulin and IGF-1 stimulated tyrosine phosphorylation of IRS-1 and Shc in a similar dose- and time-dependent manner. The time course of Shc phosphorylation by both IGF-1 and insulin was slower than that of IRS-1. Both phosphorylated IRS-1 and Shc associated with Grb2.Sos complexes, leading to p21ras activation. To compare the functional importance of p21ras for IGF-1-and insulin-induced DNA synthesis, single cell microinjection studies were performed. BrdU incorporation into newly synthesized DNA was measured by immunofluorescence microscopy to assess the functional importance of p21ras. Both IGF-1 and insulin stimulated BrdU incorporation, but the effect of IGF-1 was greater. Microinjection of anti-p21ras antibody completely inhibited both IGF-1-and insulin-induced DNA synthesis, indicating the central role of p21ras in signaling by both hormones. Signal transduction from these receptors to Grb2.Sos complexes can occur through IRS-1 and/or Shc. To assess these two possible pathways, we performed Western blots for Grb2 in anti-Shc and anti-IRS-1 immunoprecipitates and found that 5-fold more Grb2 was associated with Shc than with IRS-1 after either IGF-1 or insulin stimulation. Microinjection of anti-Shc antibody inhibited IGF-1 and insulin stimulation of DNA synthesis by 78% and 74%, respectively. By microinjecting Shc subdomains of GST fusion proteins, we found that Shc N-terminus, but not the Shc SH2, was the functionally important domain through which Shc interacts with IGF-1 and insulin receptors. Insulin stimulation caused hyperphosphorylation and decreased electrophoretic mobility of Sos, and a similar effect was seen with IGF-1, although the time course was delayed compared with insulin. Finally, IGF-1 activated mitogen-activated proten kinase activity more effectively than insulin. These data indicate that Shc, rather than IRS-1, appears to be the predominant functional link to Grb2.Sos complexes from the IGF-1 receptor, as it is from the insulin receptor. Although IGF-1 and insulin stimulate cell cycle progression with similar coupling mechanisms from the receptor to Shc, to Grb2.Sos, to p21ras, the delayed IGF-1 induced mobility shift of Sos could lead to, at least in part, more efficient coupling to mitogen-activated protein kinase. These findings might explain the greater mitogenic activity of IGF-1 compared with insulin.
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422
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Takanami I, Imamura T, Hashizume T, Kikuchi K, Yamamoto Y, Yamamoto T, Kodaira S. Immunohistochemical detection of basic fibroblast growth factor as a prognostic indicator in pulmonary adenocarcinoma. Jpn J Clin Oncol 1996; 26:293-7. [PMID: 8895667 DOI: 10.1093/oxfordjournals.jjco.a023235] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The expression of basic fibroblast growth factor (bFGF) was studied immunohistochemically in tissue specimens from 157 patients with pulmonary adenocarcinoma. Tumor cells that expressed bFGF were found in 89 patients (74%). The expression of bFGF was correlated with T and M in the TNM classification, disease stage and curability. The 5-year survival rate was 24% in bFGF-positive patients but 66% in bFGF-negative patients, the difference being significant (P<0.01). The 5-year survival rate of patients with stage I disease was 73% in those who were bFGF-positive but 88% in those who were bFGF-negative, the difference being significant (P<0.05). Multivariate analysis showed that the expression of bFGF was significantly related to prognosis. These findings suggest that bFGF plays an important role in tumor progression and that its expression may be a useful prognostic indicator for pulmonary adenocarcinoma.
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423
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Ohshio G, Tanaka T, Imamura T, Okada N, Yoshitomi S, Suwa H, Hosotani R, Imamura M. Exocrine pancreatic function in the early period after pancreatoduodenectomy and effects of preoperative pancreatic duct obstruction. Dig Dis Sci 1996; 41:1947-52. [PMID: 8888705 DOI: 10.1007/bf02093594] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Exocrine pancreatic function in the early period after pancreatoduodenectomy was investigated. The effects of preoperative pancreatic duct obstruction on exocrine pancreatic function were also investigated. The volume of pancreatic juice and its amylase activity were investigated in 39 patients who underwent pancreatoduodenectomy (including pylorus-preserving pancreatoduodenectomy). The N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BT-PABA) test was performed on 23 of 39 patients about 40 days after pancreatoduodenectomy. The exocrine pancreatic function was inhibited three to eight days after pancreatoduodenectomy (amylase activity: 23,700 +/- 4300 IU/day), and recovered on days 9-15 (48,000 +/- 8400 IU/day) in patients with a normal main pancreatic duct. In patients with pancreatic duct obstruction, the exocrine pancreatic function was almost eliminated (amylase activity: 440 +/- 260 IU/day) and BT-PABA test results were low (45 +/- 17%). In patients with narrowed pancreatic duct, amylase secretion was significantly inhibited even in patients with a normal number of acinar cells. There was a good positive correlation (Spearman's rank correlation coefficient, rs = 0.715, P < 0.01) between amylase secretion and BT-PABA test. Amylase secretion more than 10,000 IU/day is essential for a normal BT-PABA test and normal digestive function. The inhibited digestive function in patients with pancreatic duct obstruction may be due to the decreased number of acinar cells and the inhibition of exocrine pancreatic function.
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424
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Okada N, Kubota A, Imamura T, Suwa H, Kawaguchi Y, Ohshio G, Seino Y, Imamura M. Evaluation of cholecystokinin, gastrin, CCK-A receptor, and CCK-B/gastrin receptor gene expressions in gastric cancer. Cancer Lett 1996; 106:257-62. [PMID: 8844981 DOI: 10.1016/0304-3835(96)04325-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The brain-gut hormones, cholecystokinin (CCK) and gastrin, regulate the growth of gastrointestinal mucosa and tumor cells. In this study, reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate messenger RNA expression for CCK, gastrin, CCK-A receptor, and CCK-B/gastrin receptor in surgical specimens of gastric cancers and in normal antrum and body mucosa of the stomach. The CCK mRNA expression was detectable in 4/14 (29%) samples of gastric cancer and in 3/12 (25%) samples of antral mucosa. However, the gastrin mRNA expression was not detectable in any gastric cancer samples, although it was detectable in all the samples of antral mucosa. The CCK-A receptor mRNA expression was detectable in 5/14 (36%) samples of gastric cancer and in 7/12 (58%) body mucosa. Three cases out of 14 (21%) of gastric cancer expressed both CCK gene and CCK-A receptor gene. The CCK-B receptor mRNA expression was detectable in only 1/14 (7%) samples of gastric cancer, although it was detectable in 10/12 (83%) body mucosa of the stomach. These findings may suggest a greater role for CCK and CCK-A receptor than for gastrin and CCK-B receptor in gastric cancers.
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425
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Ozawa K, Uruno T, Miyakawa K, Seo M, Imamura T. Expression of the fibroblast growth factor family and their receptor family genes during mouse brain development. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1996; 41:279-88. [PMID: 8883961 DOI: 10.1016/0169-328x(96)00108-8] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The fibroblast growth factor (FGF) family is composed of nine members and four genes encode protein tyrosine kinase receptors for them. To gain insight into the involvement of FGFs and their receptors in the development of nervous system, their expression in brains of perinatal and adult mice was examined by semi-quantitative reverse transcription-linked polymerase chain reactions and in situ hybridization. Although all the genes, with the exception of FGF-4, were found to be expressed, FGF-3, FGF-6, FGF-7 and FGF-8 genes demonstrated higher expression in the late embryonic stages than in postnatal stages, suggesting that these members are involved in the late stages of brain development. In contrast, expression of FGF-1 and FGF-5 increased after birth. Interestingly, FGF-6 expression in perinatal mice was restricted to the central nervous system and skeltal muscles, with intense signals in the developing cerebrum in embryos but in cerebellum in 5-day-old neonates. Furthermore, FGF-receptor (FGFR)-4, a cognate receptor for FGF-6, demonstrated similar spatiotemporal expression, suggesting that FGF-6 and FGFR-4 plays significant roles in the maturation of nervous system as a ligand-receptor system. The results indicate that individual member of the fibroblast growth factor and their receptor family are expressed either sequentially or simultaneously in brain development, strongly suggesting their involvement in the regulation of a variety of developmental processes of brain, i.e., proliferation and migration of neuronal progenitor cells, neuron and glia differentiation, neurite extensions, and synapse formations.
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