2476
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Yamamoto M. [Involvement in morphological changes of the articular cartilage of rat temporomandibular joint induced by experimental malocclusion]. FUKUOKA IGAKU ZASSHI = HUKUOKA ACTA MEDICA 1994; 85:78-90. [PMID: 8175104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The effect of malocclusion induced by increase in unilateral occlusal vertical dimension on the articular cartilage of rat mandibular condyle was histologically and immunohistologically examined. WKA rats (8 weeks) were divided into three group A: untreated (control) rats, group B: rats forced to mouth open just for 20 min, and group C: rats given malocclusion by putting the 1 mm diameter wire on the right upper molar continuously. After treatment, each rat was sacrificed periodically up to 9 weeks, and the morphological changes of condylar cartilage (articular, embryonic and transitional zones of cartilage layer) were histologically investigated. The thickness of articular cartilage in all groups was decreased in a time-dependent manner (up to 9 weeks after treatment). In group C rats, whose articular cartilage was thinnest in three groups, the reduced thickness of cartilage in the non-treated side (the left side) was same as that in the treated side which was presented with excessive molar contact. But, its occurrence in the treated side was seen 2 weeks earlier than that in the non-treated side. Even in group B rats which were only forced to open the mouth for 20 min without setting of permanent malocclusion, the thickness of condylar cartilage was decreased more than that of group A rats. When the condylar cartilages of all three groups were immunohistologically examined with anti-interleukin-1 (IL-1) antibody in order to investigate the pathophysiological involvement of IL-1, which is well-known catabolic factor to cartilage, some chondrocytes in articular cartilage were positively stained. The ratio of IL-1 positive cells increased time-dependently. IL-1-producing cells in group B and the non-treated side of group C reached to the maximal ratio at the same time when the condylar cartilage markedly decreased in thickness. However, the ratio of IL-1-positive chondrocytes in the treated side of group C was maximal four weeks after the decrease of cartilage thickness. In respect with the size of cells in cartilage, the occurrence of decreased thickness in condylar cartilage corresponded to that of the reduction of cellular size, especially in the embryonic zone of group C. These results described above suggest that malocclusion, unilateral immature occlusion, can induce the thinning of condylar cartilage which may result from the reducing size of articular chondrocytes (differentiated chondrocytes) and the accompanying decreased cartilage matrix. This change of cartilage may be caused by IL -1 that articular chondrocyte seemed to produce.(ABSTRACT TRUNCATED AT 400 WORDS)
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2477
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Igarashi K, Kataoka K, Itoh K, Hayashi N, Nishizawa M, Yamamoto M. Regulation of transcription by dimerization of erythroid factor NF-E2 p45 with small Maf proteins. Nature 1994; 367:568-72. [PMID: 8107826 DOI: 10.1038/367568a0] [Citation(s) in RCA: 372] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Transcription factor NF-E2 is crucial for regulating erythroid-specific gene expression. Cloning of the NF-E2 p45 protein has revealed that it contains a basic region-leucine zipper (b-zip) domain which associates with another unidentified protein (of relative molecular mass 18,000) to form functional NF-E2. We show here that products of the maf proto-oncogene family, MafF, MafG and MafK (the small Maf proteins) which possess a b-zip DNA-binding domain but lack a canonical transactivation domain, directly control the DNA-binding properties of p45 by heterodimeric association with p45. Whereas homodimers of the small Maf proteins act as negative regulators, heterodimers composed of Maf and p45 support active transcription in vivo. These results indicate that one (or all) of the small Maf proteins is the second constituent chain required for NF-E2 activity, and that negative as well as positive regulation can be achieved through an NF-E2 site, depending on the equilibrium concentrations of p45 and the Maf proteins inside erythroid cells.
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2478
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Takeshita S, Kawase H, Yamamoto M, Fujisawa T, Sekine I, Yoshioka S. Increased expression of human 63-kD heat shock protein gene in Kawasaki disease determined by quantitative reverse transcription-polymerase chain reaction. Pediatr Res 1994; 35:179-83. [PMID: 8165052 DOI: 10.1203/00006450-199402000-00010] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To investigate the possible role of heat shock protein (HSP) in the pathogenesis of Kawasaki disease (KD), we determined the expression of 63-kD HSP (P1 protein) gene in the leukocytes from the peripheral blood of 20 patients with KD, 20 patients with various other febrile diseases, and 10 healthy children using the quantitative reverse transcription-polymerase chain reaction technique. Although a low but constitutive expression of HSP was observed in the control patients and healthy children, the expression of HSP63 mRNA was significantly higher during the acute phase of KD. Because mycobacterial HSP65, a cognate of human HSP63, is a common immunogen in bacterial species, and because the major immunopathologic feature of KD is reportedly an abnormally activated immune system, it suggests that an increased level of HSP63 gene transcription may be associated with the pathogenesis of KD.
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2479
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Ohira A, Honda O, Gauntt CD, Yamamoto M, Hori K, Masutani H, Yodoi J, Honda Y. Oxidative stress induces adult T cell leukemia derived factor/thioredoxin in the rat retina. J Transl Med 1994; 70:279-85. [PMID: 8139268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Adult T cell leukemia derived factor (ADF), originally defined as an interleukin-2 receptor inducer, is a human thioredoxin homolog. ADF/thioredoxin has several biologic functions, such as defense against cellular damage, activity to scavenge oxidative stress by hydrogen peroxide radicals and cytokine-like properties. We hypothesized that under certain conditions, ischemia followed by reperfusion and/or light exposure, ADF may be induced in the retina. EXPERIMENTAL DESIGN To test this hypothesis, we prepared experimental animal models in which oxidative stress could be applied to the retina. In the present study, we examined ADF expression in the rat retina using temporary ischemia and reperfusion, and photodynamic retinal vascular thrombosis by immunohistochemical and Western blotting methods. RESULTS ADF expression was strongly induced in the retinal pigment epithelial cells after 2 hours of ischemia followed by 2, 24, or 48 hours of reperfusion. ADF was also expressed in retinal pigment epithelial cells as early as 3 hours after light exposure followed by rose bengal injection, and this expression increased with time. Western blotting data showed that ADF expression increased in the retinal pigment epithelial cells in the experimental group, as compared with the control group. These results indicate that ADF is actively induced in retinal pigment epithelial cells upon oxidative stress. CONCLUSIONS ADF induction in retinal pigment epithelial cells may be involved in the defense mechanism against cellular damage caused by active oxygen species generated during oxygen stress to the retina.
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2480
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Imai Y, Yamamoto M. The fission yeast mating pheromone P-factor: its molecular structure, gene structure, and ability to induce gene expression and G1 arrest in the mating partner. Genes Dev 1994; 8:328-38. [PMID: 8314086 DOI: 10.1101/gad.8.3.328] [Citation(s) in RCA: 112] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Schizosaccharomyces pombe h+ cells secrete a diffusable mating pheromone called P-factor. Here we show that the map2 gene, a defect of which confers h(+)-specific sterility, encodes the precursor of P-factor. We purified P-factor from cells overexpressing map2 and determined its amino acid sequence. P-factor is a peptide of 23 residues, with the sequence Thr-Tyr-Ala-Asp-Phe-Leu-Arg-Ala-Tyr-Gln-Ser- Trp-Asn-Thr-Phe-Val-Asn-Pro-Asp-Arg-Pro-Asn-Leu. A synthetic peptide of this sequence gave the same specific activity and chromatographic profile as the purified P-factor, suggesting that P-factor is unmodified. h- cells starved for nutrition showed a morphological response to P-factor. Transcription of the sxa2 gene, which encodes a protease thought to degrade P-factor, was activated in these cells. The cry1 null mutant, which lacks adenylyl cyclase and has little intracellular cAMP, was susceptible to P-factor even in the presence of nutrients. Combination of the cyr1 and sxa2 mutations enhanced this susceptibility. P-factor induced not only responses toward mating but also arrest of the cell cycle at the G1 phase in h- cyr1 sxa2 cells. This proves that the S. pombe mating pheromone has the ability to arrest cell cycle progression, which has previously been obscured by the usual requirement for mating of nutritional starvation and subsequent growth arrest.
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2481
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Tanaka S, Fujihara A, Yamamoto M, Asano M, Ida H, Ohmi Y, Kitazaki T, Kikuchi Y, Yoshida S, Okamiya H. [Anti-tumor activity of zinostatin stimalamer (YM 881) examined by human hepatoma cells in vitro and VX2 liver tumor in vivo]. Gan To Kagaku Ryoho 1994; 21:219-26. [PMID: 8311492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Anti-tumor activities of zinostatin stimalamer (YM 881) were examined using human hepatoma cell lines (SK-Hep1 and HuH 2) and VX2 liver tumor-bearing rabbits. YM881 inhibited the growth of human hepatoma cells in a dose-dependent manner. The IC50 values of YM881 against SK-Hep 1 and HuH 2 cells were 6.7 and 27 mM, respectively. In VX2 tumor-bearing rabbits, administration of YM 881 suspended in iodinated fatty acid ethylesters of poppyseed oil (YM 881/Lipiodol suspension, 0.2 mg/0.2 ml/body) into the hepatic artery showed significant (p < 0.01, vs sham-operated and Lipiodol-treated groups) inhibitory effects on the growth and pathological changes 1 and 2 weeks after administration. On the other hand, Lipiodol (0.2 ml/body) showed a tendency to inhibit the growth of VX2 tumor (p < 0.1, vs sham-operated group) 1 week after administration, but it showed only moderate effects on the VX2 tumor growth 2 weeks after administration. Minimal necrosis was observed 1 and 2 weeks after administration of Lipiodol, and these pathological findings were similar to those in the sham-operated group. From the present study, it is suggested that YM 881/Lipiodol suspension showed the anti-tumor activity against VX2 tumor-bearing rabbits, presumably due to the inhibition of the growth of hepatoma cell by YM 881 per se. On the other hand, Lipiodol is considered to augment the anti-tumor activity by maintaining high YM881 concentrations in tumor tissue.
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2482
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Kajita K, Ishizuka T, Yamamoto M, Nagashima T, Taniguchi O, Mune T, Murayama M, Kitagawa S, Yasuda K. ACTH and phorbol ester stimulated redistribution of protein kinase C in human cortisol-producing adrenal adenoma. Endocr J 1994; 41:107-13. [PMID: 7951545 DOI: 10.1507/endocrj.41.107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We studied the steroidogenetic action and concomitant subcellular redistribution of protein kinase C (PKC) in cortisol hypersecreting adrenal adenoma cells obtained from two patients with Cushing's syndrome. Isolated adenoma cells were treated with 10(-9) M and 10(-6) M 12-O-tetradecanoyl phorbol-13-acetate (TPA) or 10(-6) M ACTH. Treatment of the isolated adenoma cells with TPA resulted in cortisol secretion equivalent to that with ACTH-treatment. Immunoblot analysis of PKC during treatment with ACTH or TPA showed that PKC beta translocated from cytosol to membrane. A small amount of PKC alpha, but not membrane-associated PKC alpha, was detectable in the cytosolic fraction. It appeared that TPA-induced cortisol secretion mimicked ACTH-induced cortisol secretion, and that PKC beta translocated from cytosol to membrane on stimulation by both ACTH and TPA. We suggested that ACTH-induced cortisol secretion in human cortisol hypersecreting adrenal adenoma is mediated by PKC beta activation.
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2483
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Rikitake Y, Morita S, Kuroda S, Ido Y, Aoyama N, Sakamoto C, Yokono K, Kasuga M, Oohashi O, Yamamoto M. [A case report of glucagonoma recurred to the lymph nodes seven years after resection of the primary tumor]. NIHON SHOKAKIBYO GAKKAI ZASSHI = THE JAPANESE JOURNAL OF GASTRO-ENTEROLOGY 1994; 91:227-31. [PMID: 8114333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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2484
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Satake I, Tari K, Nakagomi K, Ozawa K, Kojima S, Yamamoto M, Nishimura H, Kishi K. Extragonadal germ cell tumor of retroperitoneal origin: report of two cases. Jpn J Clin Oncol 1994; 24:46-50. [PMID: 8126921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Two cases of primary extragonadal germ cell tumor of retroperitoneal origin are reported. One was a 26-year-old man complaining of back pain. He had a large retroperitoneal tumor with lung, liver and supraclavicular lymph node metastases. He was referred to us after being treated for malignant lymphoma. The serum AFP, beta-subunit of human chorionic gonadotropin (hCG-beta), CEA and CA-19-9 were elevated. The retroperitoneal disease was treated surgically and with radiotherapy. The pathological diagnosis was that of embryonal carcinoma and teratoma. The lung, liver and supraclavicular lymph node metastases disappeared completely after two courses of cisplatin-based chemotherapy. While further chemotherapy was postponed due to myelosuppression, the disease relapsed and was resistant to subsequent therapy. The patient died twelve months after he first saw us. The second case was that of a 36-year-old man complaining of edematous legs and external genitalia. He had an extensive retroperitoneal tumor with multiple pulmonary metastases. The serum AFP level was high. Suspected of having an extragonadal germ cell tumor, he was referred to us promptly. Cisplatin-based chemotherapy coupled with resection of residual retroperitoneal and pulmonary disease resulted in complete remission. The pathological diagnosis was that of possible embryonal carcinoma. Further chemotherapy was given as scheduled, using granulocyte colony-stimulating factor. The patient has been in complete remission for two years. The chemotherapeutic regimen and surgical policy in the treatment of the two patients were essentially same. Early diagnosis, adequate initial therapy and the use of granulocyte colony-stimulating factor may be relevant to the favorable prognosis in the latter case.
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2485
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Sato S, Ina Y, Takada K, Sato T, Ito S, Sahashi K, Yamamoto M, Morishita M. [Levels of soluble CD4 and soluble CD8 in patients with sarcoidosis]. NIHON KYOBU SHIKKAN GAKKAI ZASSHI 1994; 32:117-24. [PMID: 8164397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Levels of soluble CD4 (sCD4) and soluble CD8 (sCD8) in serum and bronchoalveolar lavage fluid (BALF) were determined in 36 patients with sarcoidosis and 20 healthy controls by an ELISA method. In addition, the possible sources of sCD4 and sCD8 were examined in detail. The sCD4 levels in serum did not differ significantly between sarcoidosis patients and controls. The sCD8 levels in the sera of sarcoidosis patients with a high serum angiotensin-converting enzyme (ACE) level were significantly higher than those of patients with a normal serum ACE level (413 +/- 148 U/ml vs. 297 +/- 76 U/ml, p < 0.01). The high ACE group also had significantly increased serum sCD8 levels as compared to controls (323 +/- 111 U/ml, p < 0.05). In the sarcoidosis patients, the mean serum sCD8 level was 308 +/- 46 U/ml in stage 0, 339 +/- 107 U/ml in stage I, 557 +/- 141 U/ml in stage II, and 474 +/- 211 U/ml in stage III. The stage II group had a significantly higher sCD8 level than either the stage 0 or I groups (p < 0.05). In the sarcoidosis patients, the sCD8 level correlated significantly with the level of either ACE or soluble Interleukin-2 receptor in serum (p < 0.05). The sCD4 level in BALF was significantly higher in sarcoidosis patients than in controls (4.10 +/- 1.90 U/ml vs. 2.39 +/- 0.12 U/ml, p < 0.01), while the sCD8 level in BALF tended to be higher in sarcoidosis patients than in controls (4.31 +/- 4.39 U/ml vs. 2.02 +/- 1.52 U/ml).(ABSTRACT TRUNCATED AT 250 WORDS)
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2486
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Baba H, Maehara Y, Takeuchi H, Inutsuka S, Yamamoto M, Endo K, Sugimachi K. Synergism of cytotoxicity between cis-diaminedichloro-platinum-(ii) and cis-diamine(1,1-cyclobutanedicarboxylate)-platinum-(ii). Int J Oncol 1994; 4:329-333. [PMID: 21566928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
In an attempts to increase the antitumor effect and to reduce normal tissue toxicity, the combined cytotoxic effect of cis-Diamminedichloroplatinum (II) (CDDP) and cis-diammine(1,1-cyclobutane dicarboxylate) platinum (II) (CBDCA) was investigated using HeLa and colon 26 cell lines and the combination index (CI). Cytotoxicity of the combination of CDDP and CBDCA on 27 surgically resected specimens of human gastric and colorectal adenocarcinomas was also evaluated using the in vitro succinate dehydrogenase inhibition (SDI) test. The CI values varied with the dose ratio examined (1:1-1:6) of CDDP and CBDCA, with findings that CI<1, synergy, was obtained at fraction affected (Fa)>0.75 for HeLa cells and at Fa<0.9 for colon 26 cells in cases of a dose ratio of 1:1 to 1:2. Of all 27 clinical human adenocarcinomas, the succinate dehydrogenase (SD) activity was significantly lower in cancer cells concomitantly exposed to both CDDP and CBDCA than in those exposed to either drug alone. These positive effects of a combination of two platinum analogues on human malignant tissues have heretofore not been reported, which would warrant the clinical application of this combination for human malignant tumors.
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2487
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Kimura K, Wakatsuki T, Yamamoto M. A variant mRNA species encoding a truncated form of Fas antigen in the rat liver. Biochem Biophys Res Commun 1994; 198:666-74. [PMID: 7507668 DOI: 10.1006/bbrc.1994.1097] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A variant form of the Fas antigen cDNA was isolated from the rat liver. The cDNA contains an insertion sequence of 25 nucleotide residues and codes for a protein consisting of 65 amino acids representing a signal peptide and an N-terminal portion of the extracytoplasmic domain of Fas antigen. The expression of a variant mRNA species is less abundant in the liver compared with that of an ordinary mRNA species. The variant mRNA, though its function is unknown, is plausibly produced by an alternative splicing.
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2488
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Yatsunami K, Ohtsu H, Tsuchikawa M, Higuchi T, Ishibashi K, Shida A, Shima Y, Nakagawa S, Yamauchi K, Yamamoto M. Structure of the L-histidine decarboxylase gene. J Biol Chem 1994; 269:1554-9. [PMID: 8288622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Two species of L-histidine decarboxylase (HDC) mRNA were found in the KU-812-F basophilic cell line, but only the 2.4-kilobase (kb) one encodes the functional HDC (Mamune-Sato, R., Yamauchi, K., Tanno, Y., Ohkawara, Y., Ohtsu, H., Katayose, D., Maeyama, K., Watanabe, T., Shibahara, S., and Takishima, T. (1992) Eur. J. Biochem. 209, 533-539). The 3.4-kb one encodes a truncated HDC protein and is also found in human leukemia-derived cell lines HEL and KCL-22. To clarify the mechanisms that regulate transcription of the HDC gene and generate the two species of mRNA, we have isolated genomic DNA clones coding for the HDC from human genomic libraries. Structural analysis of the isolated clones revealed that the human HDC gene is composed of 12 exons spanning approximately 24 kb. Genomic DNA blot analysis suggested that HDC is encoded by a single copy gene. The structural analysis also demonstrated that the heterogeneity of the HDC mRNA is caused by an insertion of the seventh intron sequence and alternative use of the splicing acceptor site at the 12th exon. The transcription start site of the HDC gene and the nucleotide sequences of the promoter and first exon regions were determined. We found a TATA-like sequence, a GC box, four CACC boxes, four GATA consensus sequences, and six leader-binding protein-1 binding motifs in the promoter region of the HDC gene.
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2489
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Akiyama K, Yamamoto M, Haida M, Ohsuga H, Shinohara N, Shinohara Y. Morphological changes of cultured neuronal and endothelial cells by human albumin. ACTA NEUROCHIRURGICA. SUPPLEMENTUM 1994; 60:38-40. [PMID: 7976596 DOI: 10.1007/978-3-7091-9334-1_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The role of plasma proteins in the mechanisms of brain tissue damage in ischemic events remains to be clarified. The purpose of this study was to investigate whether the presence of albumin in the extracellular fluid could induce damage to endothelial and neuronal cells. Neuronal cells from rat fetal brain (15 days) were cultured by using RPMI-1640 containing 10% Serum-Plus and endothelial cells from umbilical vein were also cultured in 96-well plates. The studies were made by using neuronal cells after 4 days of culture (N group) and endothelial cells after 4 days of culture (E4 group) and at confluence (EC group). After discarding the culture fluid, 200 microliters of 5-25% human albumin was added to each well. Microscopic observations were made up to 20 minutes, and then immunostaining was done with anti-human albumin antibody. The swelling of neurons was observed immediately after application of albumin solution, and the cells became circular after 10 minutes. In the E4 group, similar morphological changes were observed, but no such changes were seen in the EC group. Immunostaining revealed the presence of albumin in the intracellular space in both the N and E4 groups, but not the EC group. Our results suggest that albumin in extravasated fluid can induce damage to neuronal cells and endothelial cells in the non-confluent state.
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2490
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Wakatsuki T, Ohira Y, Yasui W, Nakamura K, Asakura T, Ohno H, Yamamoto M. Responses of contractile properties in rat soleus to high-energy phosphates and/or unloading. THE JAPANESE JOURNAL OF PHYSIOLOGY 1994; 44:193-204. [PMID: 7967221 DOI: 10.2170/jjphysiol.44.193] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Responses of contractile properties of soleus to unloading and/or changes in high-energy phosphate contents were studied in rats. Reduction of high-energy phosphates, especially phosphocreatine, in ankle extensors was induced by feeding beta-guanidinopropionic acid (beta-GPA). The major finding in the study was that the fatigability and speed-related contractile properties responded to unloading and creatine supplementation in a similar manner. The high-energy phosphate contents tended to be elevated after 10-d supplementation of creatine and hindlimb suspension. The shift toward slow-type, mainly due to an increased one-half relaxation time, was seen in rats fed beta-GPA. Such a shift was reversed by feeding creatine or by hindlimb suspension; however, the suspension-induced shift of contractile properties toward fast-type was not prevented completely by beta-GPA feeding. Although the muscle fatigue resistance did not change by beta-GPA feeding alone, the decrease in fatigue resistance following suspension and creatine supply was less in the beta-GPA group. It is suggested that the levels of high-energy phosphates and tension production play important roles in the regulation of contractile properties of the soleus muscle.
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2491
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Yamamoto M, Kanzaki J, Ogawa K, Inoue Y, Ikeda S. Hearing recovery and vestibular symptoms in patients with sudden deafness and profound hearing loss. ACTA OTO-LARYNGOLOGICA. SUPPLEMENTUM 1994; 514:41-4. [PMID: 8073883 DOI: 10.3109/00016489409127556] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Audiometric data from 76 patients with unilateral sudden deafness and hearing loss of 80 dB or more were studied to statistically assess the relationship between vestibular findings (vertigo and/or dizziness, nystagmus, canal paresis) and hearing recovery in various frequency ranges. Hearing recovery in patients with vertigo and/or dizziness (V(+)) was much poorer than in patients without such findings (V(-)). Concerning hearing recovery in the high frequency range, a significant statistical difference was evident between the V(+) and V(-) group. There were no statistically significant differences in hearing recovery between patients with spontaneous nystagmus or canal paresis and those without.
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2492
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Nakamura Y, Kobayashi M, Nagai M, Iwata H, Nose T, Yamamoto M, Omura T, Motegi K, Kurosawa Y, Hossaka K. A case-control study of ulcerative colitis in Japan. J Clin Gastroenterol 1994; 18:72-9. [PMID: 8113591 DOI: 10.1097/00004836-199401000-00017] [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: 01/28/2023]
Abstract
To determine whether risk factors of ulcerative colitis among Japanese are the same as those observed in other countries, we conducted a case-control study in Japan in 1988-90. Patients selected for the study were receiving financial aid for treatment of the disease; an equal number of population-based controls matched by age and sex were selected. Smoking decreased the risk of the disease (odds ratio = 0.30; 95% confidence interval, 0.16-0.56), and stopping smoking increased the risk (odds ratio compared with those who had never smoked = 1.44; 95% confidence interval, 0.73-2.85). In those who drank alcoholic beverages > or = 5 days a week, disease development was less likely than in others (odds ratio = 0.49; 95% confidence interval, 0.30-0.81). In addition, difficulties in human relations at work, a family history of asthma, a medical history of surgical procedures, and personality traits such as nervousness, anxiety, and obsessive behavior were also considered risk factors. Although some findings are similar to those in former studies, a few findings are different: surgical procedures, occupational status, and a family history of the disease. To clarify whether the differences are consistent will require other case-control studies.
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2493
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Yamamoto M, Nishimura M, Kobayashi S, Akiyama Y, Miyamoto K, Kawakami Y. Role of endogenous adenosine in hypoxic ventilatory response in humans: a study with dipyridamole. J Appl Physiol (1985) 1994; 76:196-203. [PMID: 8175505 DOI: 10.1152/jappl.1994.76.1.196] [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: 01/29/2023] Open
Abstract
To examine the role of endogenous adenosine in hypoxic ventilatory response, we measured, in nine normal young adults, ventilatory responses to isocapnic progressive hypoxia and subsequent sustained hypoxia [arterial O2 saturation (SaO2); 80%, 20 min] with and without pretreatment with dipyridamole in a double-blind crossover fashion. Dipyridamole, an adenosine uptake blocker, was expected to enhance the effect of endogenous adenosine. Pretreatment with dipyridamole (0.5 mg/kg) significantly augmented the slope of the ventilatory response to isocapnic progressive hypoxia from 0.35 +/- 0.13 (SE) to 0.70 +/- 0.25 l.min-1.%fall of SaO2(-1) (P < 0.01), although there were no significant changes in resting ventilation. On the other hand, minute ventilation, when expressed as a percentage of peak ventilation, declined to 68.4 +/- 4.3% with dipyridamole at the 9-11th min of sustained hypoxia, which was significantly lower than the 90.2 +/- 8.3% with a placebo (P < 0.05), and finally reached 56.1 +/- 7.2% with dipyridamole and 78.7 +/- 9.2% with the placebo (P < 0.1) at the 18-20th min of sustained hypoxia. In an attempt to more specifically examine the role of adenosine, aminophylline (5 mg/kg), an adenosine receptor antagonist, was injected before pretreatment with dipyridamole in four subjects. Aminophylline infusion abolished or at least attenuated the effect of dipyridamole in all four subjects. These data suggest that endogenous adenosine has a modulatory role in hypoxic ventilatory response in adult humans.
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2494
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Nagai M, Yamamoto M, Numata T. Current assessment and proposed improvement to emergency medical information systems in Japan. MEDICAL INFORMATICS = MEDECINE ET INFORMATIQUE 1994; 19:21-36. [PMID: 7934302 DOI: 10.3109/14639239409044718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Most prefectural governments in Japan have been implementing, or planning to implement, emergency medical information systems that take advantage of advanced information-related technologies such as computers and communication systems, in order to improve their emergency medical care systems. We studied the emergency medical information systems to analyse their present status, clarify their purpose, and present the ideal system, in view of community health care requirements. Here the results of the research are examined, and there is a discussion of what is needed to improve the system in the future. The emergency medical information system in Aichi prefecture is taken as an example, to closely survey its present situation and analyse the evaluation of the system by the residents who are the major beneficiaries of the system.
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2495
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Haida M, Shinohara Y, Yamamoto M, Nagayama T, Kurita D. The effect of BAY K-8644 on cytotoxic edema induced by total ischemia of rat brain. ACTA NEUROCHIRURGICA. SUPPLEMENTUM 1994; 60:293-295. [PMID: 7526624 DOI: 10.1007/978-3-7091-9334-1_78] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The calcium channel activator BAY K-8644, a dihydropyridine (DHP) derivative, has been shown to possess neurochemical and behavioral activities, but its effect on ischemic brain damage has remained unknown. This report describes the effect of the drug on the progression of cytotoxic edema induced by total ischemia of the brain, evaluated by measuring the time constant, k, of elongation of the 1H-NMR relaxation time (T2) after brain biopsy. Twenty-six male Wistar rats were divided into four groups, (a) control (saline) group (n = 10), (b) BAY K-8644 vehicle group (n = 4), (c) BAY K-8644 0.03 mg/kg group (n = 6) and (d) BAY K-8644 0.3 mg/kg group (n = 6). The k value of group (d), 18.2 +/- 5.8 min (mean +/- SD), was significantly higher compared with those of groups (a) 10.3 +/- 1.6, (b) 11.8 +/- 1.5 and (c) 9.8 +/- 3.3 min (p < 0.01 by ANOVA). These results indicate that BAY K-8644 delayed the progression of cytotoxic edema induced by total ischemia of the rat brain.
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2496
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Ito S, Ina Y, Hashiba H, Takada K, Sato T, Sato S, Sahashi K, Yamamoto M, Miyachi A, Morishita M. [Clinical study of anti-phospholipid antibody in patients with sarcoidosis]. NIHON KYOBU SHIKKAN GAKKAI ZASSHI 1994; 32:3-8. [PMID: 8114370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Serum antibodies against five types of phospholipids were measured by enzyme-linked immunosorbent assay (ELISA) in 55 patients with sarcoidosis. In 21 cases (38%), either IgG antibodies or IgM antibodies were detected. These antibodies were thought to mainly be infective type. This positive rate was significantly higher than that (7%) of the control group (70 cases) (p < 0.01). As to the immunoglobulin classes, 5 cases had IgG antibodies only, 11 cases had IgM antibodies only, and 5 cases had both IgG and IgM antibodies. No correlation was observed between the occurrence of anti-phospholipid antibodies (APL-Ab) and disease activity of sarcoidosis. Significant correlations were found between the occurrence of APL-Ab and skin lesions, many extrathoracic organ lesions and the persistence of abnormal chest X-ray findings for over 2 years and 5 years. From these data, it is suggested that the presence of APL-Ab is associated with prolonged disease activity of sarcoidosis.
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2497
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Yasuda M, Sakai K, Oribe M, Yoshioka K, Takahashi H, Ohtsuka E, Wada T, Shiokawa S, Yamamoto M, Ichibangase Y. Efficacy of additive DMARD therapy in patients with rheumatoid arthritis. Double blind controlled trial using bucillamine and placebo with maintenance doses of gold sodium thiomalate. J Rheumatol Suppl 1994; 21:44-50. [PMID: 8151586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE To examine the efficacy of the addition of small doses of additional disease modifying antirheumatic drugs (DMARD) to ongoing DMARD treatment [additive DMARD therapy (ADT)]. METHODS A 3-month prospective, double blind, randomized, placebo controlled study was performed using either 100 mg/day of bucillamine (Buc) or an inactive placebo (P1). Two groups of 12 patients each who had experienced an insufficient benefit from gold sodium thiomalate (GSTM) alone were enrolled in the study. RESULTS The addition of Buc proved more beneficial than P1 regarding improvement in disease activity (p = 0.0032) and drug usefulness (p = 0.0025). A significant within group improvement was observed in joint swelling count, the Lansbury activity index, erythrocyte sedimentation rate and C-reactive protein. However, the difference in the clinical variables between the 2 groups was minimal. CONCLUSION The usefulness of ADT was suggested by this trial; however, further confirmation by additional studies is still needed.
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2498
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Yotsumoto F, Manabe T, Kyogoku T, Hirano T, Ohshio G, Yamamoto M, Imamura T, Yoshitomi S. Platelet-activating factor involvement in the aggravation of acute pancreatitis in rabbits. Digestion 1994; 55:260-7. [PMID: 7520402 DOI: 10.1159/000201158] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Platelet activating factor (PAF) was administered to anesthetized rabbits with cerulein-induced acute pancreatitis to investigate the role of PAF in the development of acute pancreatitis. In acute edematous pancreatitis, induced with cerulein 20 micrograms/kg/h i.v. for 5 h, blood flow in the gastroduodenal and superior mesenteric arteries (GDAF and SMAF) had decreased significantly by 30 min and the serum amylase and lipase levels were significantly increased in the early phase. In the cerulein+PAF group, in which PAF was injected 100 ng/kg/min i.v. for 20 min simultaneously with cerulein, GDAF and SMAF declined significantly to 52 +/- 4 and 47 +/- 3% (p < 0.05), serum amylase and lipase levels rose significantly to 1,110 +/- 150 and 1,370 +/- 190% (p < 0.01) at 300 min, much higher than in the cerulein group. Furthermore, scattered hemorrhages and more marked inflammatory cell infiltration were observed histologically. These findings suggest that PAF has an additive role in the aggravation of acute pancreatitis.
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2499
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Gotoh O, Yamamoto M, Tamura A, Sano K. Effect of YM737, a new glutathione analogue, on ischemic brain edema. ACTA NEUROCHIRURGICA. SUPPLEMENTUM 1994; 60:318-20. [PMID: 7976578 DOI: 10.1007/978-3-7091-9334-1_85] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We investigated the effect of YM737, a monoester of glutathione (GSH), on brain edema and GSH content after occlusion of a middle cerebral artery (MCA) in the rat. The drug possesses stronger radical scavenging activity than GSH itself, and is more effectively transported into cells. Hemispheric water, sodium, and potassium contents were determined at 2.5 and 24 hours after MCA occlusion. The animals received either YM737 or GSH immediately after occlusion. Cerebral GSH content was measured by HPLC after 2.5 hours of ischemia. The increases in water and sodium contents at 2.5 and 24 hours after MCA occlusion were significantly suppressed by YM737. GSH content decreased by 53% in the caudate, and by 22% in the cortex after ischemia. YM737 significantly ameliorated the GSH decrease in the caudate, while administration of GSH showed little effects on the ischemia-induced changes in water, sodium, and GSH contents. The result suggests the role of free radicals in the pathogenesis of ischemic brain edema.
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2500
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Tanabe K, Osada N, Noda K, Yamamoto M, Omiya K, Itoh H, Kamegai M, Murayama M, Sugai J. [Changes in hemodynamics and catecholamines during single-level exercise at the anaerobic threshold and 120% of the anaerobic threshold in normal subjects]. J Cardiol 1994; 24:61-9. [PMID: 8158532] [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: 01/29/2023]
Abstract
Exercise training usually involves the sustained performance of exercise at a prescribed intensity. The effects of exercise performed at the anaerobic threshold (AT) have been widely studied. The effects of single-level exercise on catecholamines and cardiac function were assessed at the AT, and at 120% of the AT in eight healthy Japanese men (mean age 21.9 +/- 1.8 years). 1) Symptom-limited exercise testing utilized the ramp protocol with a bicycle ergometer (20 watts/min) for measuring AT and peak oxygen uptake (peak VO2). 2) Exercise testing was repeated on another day, following the same protocol, with blood sampled to measure norepinephrine (NE) and epinephrine (E) in the resting control state and at the AT and peak exercise. 3) Single-level exercise testing at the AT and at 120% of AT utilized the bicycle ergometer on yet another day. Blood for measurement of NE and E was drawn at 3 and 7 min after achieving a steady-state condition. In addition, the cardiac index (CI) and stroke index (SI) were measured by the CO2 rebreathing method. (1) Mean AT and peak VO2 were 18.3 +/- 1.3 and 40.2 +/- 3.0 ml/min/g, respectively. (2) NE and E measured during ramp exercise testing increased rapidly when the intensity of exercise exceeded the AT. NE measured after 3 and 7 min at the AT during single-level exercise equalled 94.7% and 94.5% of the NE value measured at the AT of ramp exercise, respectively. NE measured after 3 and 7 min at 120% of the AT during single-level exercise was 124.7% and 144.7% at the AT of ramp exercise, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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