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Yokoyama Y, Shigeto K, Gogol P, Miltat J, Thiaville A, Kawagoe T, Suzuki Y, Ono T, Shinjo T, Yuasa S, Ando K. Kerr Microscope Observation of Microfabricated NiFe Wires. ACTA ACUST UNITED AC 2000. [DOI: 10.3379/jmsjmag.24.555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Yuasa S, Li X, Hitomi H, Hashimoto M, Fujioka H, Kiyomoto H, Uchida K, Shoji T, Takahashi N, Miki S, Miyatake A, Mizushige K, Matsuo H. Sodium sensitivity and sympathetic nervous system in hypertension induced by long-term nitric oxide blockade in rats. Clin Exp Pharmacol Physiol 2000; 27:18-24. [PMID: 10696524 DOI: 10.1046/j.1440-1681.2000.03197.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. Pharmacological inhibition of nitric oxide (NO) synthesis is known to produce acute and chronic hypertension in many animal species, but the underlying mechanisms mediating the hypertension are not completely understood. In particular, the pathogenetic roles of sodium sensitivity and the sympathetic nervous system in this model of hypertension are controversial. The present study was designed to test the hypothesis that long-term administration of the NO synthesis inhibitor NG-nitro-L-arginine methyl ester (L-NAME) to male Sprague-Dawley rats would produce a sodium-sensitive hypertension and that the enhanced activity of the sympathetic nervous system in this type of hypertension contributes to the sodium sensitivity. 2. NG-Nitro-L-arginine methyl ester was added to drinking fluid for 8 weeks at a concentration of 16 mg/dL. Rats received tap water for the first 4 weeks of the study and were then divided into two groups and placed on either a normal or high sodium intake (ingestion of either tap water or 0.9% NaCl, respectively). Awake systolic blood pressure was measured by the tail-cuff method every week. Urinary excretion rates of the stable NO metabolites and catecholamines during NO synthesis inhibition were examined. 3. Long-term administration of L-NAME produced a marked and sustained elevation in arterial pressure without altering urine flow, or sodium excretion rate. NG-Nitro-L-arginine methyl ester-induced hypertension was accompanied by a decreased urinary excretion of the stable NO metabolites NO2- and NO3- and was aggravated when rats drank 0.9% NaCl in place of tap water. Urinary excretion of adrenaline and noradrenaline, but not dopamine, in L-NAME-treated rats increased significantly within the first week of the study compared with control rats. L-Arginine (2 g/dL in drinking fluid) completely reversed the elevation of arterial pressure as well as the decrease in urinary NO2- and NO3- excretion and the increased urinary excretion of catecholamines associated with L-NAME treatment by 3 weeks of concomitant administration. 4. These results suggest that long-term inhibition of NO synthesis produces a sodium-sensitive hypertension and that changes in sympathetic nerve activity may, at least in part, contribute to the sodium sensitivity in this type of hypertension.
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Ohara R, Yamakawa H, Nakayama M, Yuasa S, Ohara O. Cellular and subcellular localization of a newly identified member of the protein 4.1 family, brain 4.1, in the cerebellum of adult and postnatally developing rats. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1999; 117:127-38. [PMID: 10567730 DOI: 10.1016/s0165-3806(99)00110-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
For obtaining a deeper insight into the properties of a newly characterized member of the protein 4.1 family, brain 4.1, the cellular and subcellular localization was investigated in the cerebellar cortex of adult and postnatally developing rats. Fluorescent immunohistochemical observations showed that brain 4.1 localized predominantly to glomeruli in the granular layer and throughout the molecular layer in adult rat cerebellar cortex. Analysis of subcellular localization of brain 4.1 by immuno-electron microscopy further demonstrated that presynaptic terminals of mossy fibers and parallel fibers, cytoplasm of granule cells and cytoplasm and/or processes of glial cells contained brain 4.1 while postsynaptic regions of the dendrites of granule cells and Purkinje cells, axons and myelin sheaths did not. Thus, one of the major subcellular destination of brain 4.1 was presynaptic terminal in the cerebellum. This was further supported by the fact that the immunostaining pattern of brain 4.1 in the cerebellum changed in a similar way to that of a synaptic terminal marker, synaptophysin during the postnatal development. Immunoblot analysis also demonstrated that contents of brain 4.1 isoforms varied in parallel with the changes of the immunostaining pattern. Biochemical analysis confirmed the presence of brain 4.1 at synaptic terminals, but there was no obvious correlation between each isoform and its subcellular localization. These results suggested that brain 4.1 is involved in the formation and maintenance of synapse as a membrane skeletal component at presynaptic terminals in the cerebellum.
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Kiyomoto H, Hitomi H, Hosotani Y, Hashimoto M, Uchida K, Kurokouchi K, Nagai M, Takahashi N, Fukunaga M, Mizushige K, Matsuo H, Yuasa S. The effect of combination therapy with interferon and cryofiltration on mesangial proliferative glomerulonephritis originating from mixed cryoglobulinemia in chronic hepatitis C virus infection. THERAPEUTIC APHERESIS : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR APHERESIS AND THE JAPANESE SOCIETY FOR APHERESIS 1999; 3:329-33. [PMID: 10608730 DOI: 10.1046/j.1526-0968.1999.00196.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cryofiltration, which has developed from double filtration plasmapheresis (DFPP) with a cooling unit, is an on-line technique to remove cryoglobulin. We report on a patient who suffered from progressive edema and renal insufficiency caused by cryoglobulinemic membranoproliferative glomerulonephritis (MPGN), probably due to chronic hepatitis C virus (HCV) infection. To remove cryoglobulins and terminate the HCV infection, we utilized combination therapy with cryofiltration and interferon-alpha injection with corticosteroids. Interferon-alpha was capable of decreasing proteinuria but not diminishing cryoglobulin. Additional cryofiltration could remove cryoglobulin to an undetectable level. This combination therapy was partially successful to reduce proteinuria and prevent the progressive deterioration of renal function. The major adverse effects of this therapy were bleeding and myelosuppression. We conclude that this combination therapy may be effective and should be considered as treatment for cryoglobulinemic MPGN.
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Toyama Y, Maekawa M, Kadomatsu K, Miyauchi T, Muramatsu T, Yuasa S. Histological characterization of defective spermatogenesis in mice lacking the basigin gene. Anat Histol Embryol 1999; 28:205-13. [PMID: 10458027 DOI: 10.1046/j.1439-0264.1999.00194.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Basigin is a transmembrane protein belonging to the immunoglobulin superfamily. In the light of the fact that knockout mice lacking the basigin gene (Bsg) are azoospermic, the phenotype in the male reproductive system was extensively examined in this study. Spermatogenesis in Bsg (-/-) mice was found to be disrupted, and arrested at the metaphase of the first meiotic division. A few germ cells differentiated into young spermatids, but they were exfoliated. The lumens of the male reproductive system were filled with round degenerated cells. Using the TUNEL method and electron microscopy, some of the degenerated cells in the testis and epididymal head were shown to be apoptotic. Crystalloids of fine tubules and unusual ectoplasmic specializations were also observed in the Sertoli cells of Bsg (-/-) mice. These specializations displayed unusual 'circular' structures. Furthermore, unusual ectoplasmic specializations covering the spermatocytes rather than the mature spermatids were found. These structures were formed as a result of the lack of mature spermatids in the Bsg (-/-) testis. Results from analyses of azoospermia in the Bsg (-/-) mice suggest that basigin, through the interactions between germ cells and Sertoli cells, is an essential factor in the growth and/or survival of spermatids.
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Furumoto TA, Miura N, Akasaka T, Mizutani-Koseki Y, Sudo H, Fukuda K, Maekawa M, Yuasa S, Fu Y, Moriya H, Taniguchi M, Imai K, Dahl E, Balling R, Pavlova M, Gossler A, Koseki H. Notochord-dependent expression of MFH1 and PAX1 cooperates to maintain the proliferation of sclerotome cells during the vertebral column development. Dev Biol 1999; 210:15-29. [PMID: 10364424 DOI: 10.1006/dbio.1999.9261] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
During axial skeleton development, the notochord is essential for the induction of the sclerotome and for the subsequent differentiation of cartilage forming the vertebral bodies and intervertebral discs. These functions are mainly mediated by the diffusible signaling molecule Sonic hedgehog. The products of the paired-box-containing Pax1 and the mesenchyme forkhead-1 (Mfh1) genes are expressed in the developing sclerotome and are essential for the normal development of the vertebral column. Here, we demonstrate that Mfh1 like Pax1 expression is dependent on Sonic hedgehog signals from the notochord, and Mfh1 and Pax1 act synergistically to generate the vertebral column. In Mfh1/Pax1 double mutants, dorsomedial structures of the vertebrae are missing, resulting in extreme spina bifida accompanied by subcutaneous myelomeningocoele, and the vertebral bodies and intervertebral discs are missing. The morphological defects in Mfh1/Pax1 double mutants strongly correlate with the reduction of the mitotic rate of sclerotome cells. Thus, both the Mfh1 and the Pax1 gene products cooperate to mediate Sonic hedgehog-dependent proliferation of sclerotome cells.
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Takahashi N, Shoji T, Matsubara K, Hitomi H, Hashimoto M, Kiyomoto H, Uchida K, Miki S, Hirohata M, Ishizu T, Akiyama K, Mizushige K, Matsuo H, Yuasa S. Effect of histamine H2-receptor antagonist on the phosphorus-binding abilities of calcium carbonate and calcium lactate in hemodialysis patients. J Am Soc Nephrol 1999; 10:1090-4. [PMID: 10232696 DOI: 10.1681/asn.v1051090] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The effect of histamine H2-receptor antagonist (famotidine) on the phosphorus-binding abilities of calcium carbonate and calcium lactate were examined in 13 chronic hemodialysis patients. In seven patients receiving calcium carbonate, famotidine (20 mg/d) was given because of gastroduodenal disorders, and calcium carbonate was replaced with calcium lactate as a phosphorus binder after 4 wk of treatment with famotidine. With the 4-wk administration of famotidine accompanied by calcium carbonate, the serum phosphorus level increased from 6.3+/-0.9 to 7.1+/-0.5 mg/dl (P<0.05). However, with the substitution of calcium lactate, the serum phosphorus level decreased significantly when compared to that before substitution (6.3+/-0.2 and 6.0+/-0.9 mg/dl after 4 and 8 wk of substitution, respectively), despite continued administration of famotidine. Serum calcium, creatinine, alkaline phosphatase, high sensitive parathyroid hormone, blood urea nitrogen, arterial blood pH, and bicarbonate were not significantly altered during the trial period. In six control patients treated with calcium carbonate alone, there were no statistical changes in serum calcium and phosphorus levels after substitution of calcium lactate for calcium carbonate. These results suggest that famotidine significantly affects the phosphorus-binding ability of calcium carbonate, but not that of calcium lactate. A careful observation of changes in the serum phosphorus level should be required in hemodialysis patients receiving calcium carbonate and histamine H2-receptor antagonists. Calcium lactate may be useful as a phosphorus binder in such hemodialysis patients.
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Ichimura H, Sakashita N, Iida T, Chisaka T, Yasuda H, Kita M, Yuasa S, Imanishi J. Differentiation of a cell line of human cervical argyrophil small cell carcinoma to macrophage lineage cells. Jpn J Cancer Res 1999; 90:523-9. [PMID: 10391092 PMCID: PMC5926105 DOI: 10.1111/j.1349-7006.1999.tb00779.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
To investigate the origin of argyrophil small cell carcinoma (ASCC) of the uterine cervix, we examined the influence of dibutyryl cyclic adenosine 3',5'-monophosphate (dB-cAMP), a known differentiation inducer, on the characteristics of an ASCC cell line, TC-YIK, which has been shown to be a useful in vitro experimental model of ASCC. In TC-YIK cells after treatment with dB-cAMP, two specific antigenic markers of macrophages, CD14 and human leukocyte antigen-DR, were detected by flow cytometric analysis. In addition, interferon-gamma mRNA was detected by reverse transcription-polymerase chain reaction and interferon-gamma protein was detected by ELISA. More than 90% of the cells stained positive for alpha-naphthyl butyrate esterase, 1% of the cells showed phagocytotic activity against Micrococcus lysodeikticus, and 22% of the cells had M. lysodeikticus adsorbed on their surface. Furthermore, granulocyte-macrophage colony stimulating factor accelerated the proliferation of TC-YIK cells. These results indicate that dB-cAMP promotes differentiation of ASCC cells to macrophages. In contrast, less than 10% of the cells showed stellate morphology, suggesting differentiation to neuronal cells after treatment with dB-cAMP, as reported previously. Thus, TC-YIK cells have been shown to differentiate both into macrophage lineage cells and neuronal cells, suggesting that ASCC originates from undifferentiated stem cells.
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Komine Y, Tanaka NK, Yano R, Takai S, Yuasa S, Shiroishi T, Tsuchiya K, Yamamori T. A novel type of non-coding RNA expressed in the rat brain. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1999; 66:1-13. [PMID: 10095072 DOI: 10.1016/s0169-328x(98)00343-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We have characterized a novel type of non-coding RNA which consists of tandem repeats of similar sequences, approximately 0.9 kb in size. This RNA, termed Bsr (brain specific repetitive) RNA, is encoded at a single locus (6 q31-->q32) in the rat genome, where 100 to 150 copies of the 0.9 kb sequences are repeated in tandem. Bsr RNA is preferentially expressed in the rat central nervous system (CNS), especially in phylogenetically old structures, such as the pareo- and archicortex, amygdala, thalamus and hypothalamus. In the developing brains, Bsr RNA is expressed in the subsets of differentiating cells but not in proliferating cells. Despite the finding that Bsr RNA appears to be conserved only among the Rattus species, the specific expression pattern of Bsr RNA suggests that it might have some role in the rat CNS.
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Suzuki-Toyota F, Ishibashi K, Yuasa S. Immunohistochemical localization of a water channel, aquaporin 7 (AQP7), in the rat testis. Cell Tissue Res 1999; 295:279-85. [PMID: 9931374 DOI: 10.1007/s004410051234] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cell volume reduction is one of the most distinct morphological changes during spermiogenesis and may be largely attributable to water efflux from the cell. A strong candidate for a water efflux route, aquaporin 7 (AQP7), which is a water channel, was studied immunohistochemically in the rat testis. Immunoreactivity was restricted within the elongated spermatids, testicular spermatozoa, and residual bodies remaining in the seminiferous epithelium. Weak but distinct immunoreactivity was first observed in the cytoplasmic mass of the spermatid at step 8 of spermiogenesis. The Golgi-like apparatus became steadily immunoreactive at step 10. The plasma membrane covering the cytoplasmic mass showed strong immunoreactivity after step 16. At this step, the middle piece of the tail also showed immunoreactivity at the portion protruding into the lumen. The whole head and distal tail, where the elongated spermatid had only a limited amount of cytoplasm, showed no immunoreactivity throughout spermiogenesis. After spermiation, the immunoreactivity of AQP7 remained at the middle piece and in the cytoplasmic droplet in the testicular spermatozoon. The present observations suggest that AQP7 contributes to the volume reduction of spermatids, since this water channel protein is localized on the plasma membrane covering the condensing cytoplasmic mass of the elongated spermatid, and since the seminiferous tubule fluid is hypertonic.
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Maekawa M, Suzuki-Toyota F, Toyama Y, Kadomatsu K, Hagihara M, Kuno N, Muramatsu T, Dohmae K, Yuasa S. Stage-specific localization of basigin, a member of the immunoglobulin superfamily, during mouse spermatogenesis. ARCHIVES OF HISTOLOGY AND CYTOLOGY 1998; 61:405-15. [PMID: 9990424 DOI: 10.1679/aohc.61.405] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Ablation of the transmembrane glycoprotein basigin leads to azoospermic mice, indicating that this gene is essential for spermatogenesis. To examine the functions of basigin in the testis, the precise localization of basigin during spermatogenesis was examined immunohistochemically. In the adult mouse testis, basigin immunoreactivity appeared on the cell surface of leptotene spermatocytes and gradually increased in intensity during the meiotic prophase. Cytoplasmic staining, as well as cell surface staining, was detected in spermatids. The most conspicuous reactivity was found in the spermatids at steps 9-11 and in the flagella of spermatids. Immuno-electron microscopic analysis demonstrated that basigin was localized not only on the plasma membranes of spermatocytes and spermatids, but also on the plasma membrane of the Sertoli cell processes which contact the spermatocytes and spermatids. Basigin immunoreactivity was also detected during postnatal development in spermatocytes and spermatids but not in spermatogonia. Experimental cryptorchid testes which contain only spermatogonia and Sertoli cells in the seminiferous epithelium showed no basigin immunoreactivity. Seven days after surgical reversal of the cryptorchid testis, spermatocytes reappeared in the tubules, along with basigin immunoreactivity. Furthermore, in sterile mutant mice, in which neither spermatocytes nor spermatids were generated, no basigin immunoreactivity was detected in the seminiferous tubules. These findings indicate that expression of basigin is concomitant with appearance of spermatocytes in the seminiferous tubule, and suggest that basigin is involved in the interaction between Sertoli cells and germ cells at specific stages of spermatogenesis.
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Furukawa T, Kubota T, Murata H, Tanino H, Yuasa S, Morita K, Ueno J, Kozakai K, Yano T. Antitumor spectra of anthracyclines against gastric cancer tissues obtained from surgical specimens with reference to P-glycoprotein expression. J Surg Oncol 1998; 69:173-7. [PMID: 9846505 DOI: 10.1002/(sici)1096-9098(199811)69:3<173::aid-jso10>3.0.co;2-h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND AND OBJECTIVES Although the mechanism of P-glycoprotein (Pgp)-related resistance of doxorubicin is known, it has not been clarified for other anthracycline derivatives. We have examined the chemosensitivity of gastric cancer tissues to three anthracyclines in relation to Pgp expression. METHODS Sixty-six surgical specimens obtained from patients with gastric cancer were subjected to histoculture drug response assay using doxorubicin (DXR), epirubicin (EPI), and 4'-O-tetrahydropyranyldoxorubicin (pirarubicin; THP). The cutoff concentrations used were 15 microg/ml for DXR and EPI and 17 microg/ml for THP. RESULTS A 50% or more inhibition index (I.I.) was regarded as sensitive, at which the correlation rates were 95.8% (23/24) and 74.2% (49/66) for DXR-EPI and DXR-THP, respectively. Twenty-six specimens were immunohistochemically stained with monoclonal antibody to Pgp, with a positive rate of 53.8% (14/26). In Pgp-positive specimens, all cases were resistant to DXR and 28.6% (4/14) of cases were sensitive to THP, while the antitumor activity of EPI was essentially identical to that of DXR. CONCLUSIONS The expression of Pgp might affect resistance to DXR and EPI, although THP may partially impair this resistance, suggesting the clinical usefulness of THP in treatment of DXR-refractory gastric carcinoma.
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Kobayashi N, Dezawa M, Nagata H, Yuasa S, Konno A. Immunohistochemical study of E-cadherin and ZO-1 in allergic nasal epithelium of the guinea pig. Int Arch Allergy Immunol 1998; 116:196-205. [PMID: 9693267 DOI: 10.1159/000023945] [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: 11/19/2022] Open
Abstract
Nasal epithelial damage during allergic inflammation was studied by observing the distribution of cell adhesion molecule E-cadherin and tight junction (zonula occludens) cell-cell contact associated protein ZO-1. The guinea pig model of nasal allergy, sensitized with intraperitoneally administered ovalbumin (OA) and subsequently challenged with OA intranasally, was used. In control epithelium, E-cadherin immunoreactivity was detected continuously along neighboring epithelial cell borders. ZO-1 spot-like immunoreactivity was detected in the apicolateral portion of epithelial cells corresponding to the tight junction (TJ) position, but no changes in immunoreactivity were found between control and challenged epithelia. In the challenged epithelium of sensitized animals, marked infiltration of eosinophils and structural changes, such as widening of the intercellular spaces and detachment of adjacent epithelial cells, were observed concurrently. In addition, spots negative for E-cadherin immunoreactivity were noted in the epithelium, associated with the extracellular deposition of eosinophil granule proteins. Immunoelectron microscopy revealed a decrease or disappearance of E-cadherin immunoreactivity, which took place not only in regions where intercellular spaces were wide and adjacent epithelial cells were detached, but also at the point of contact between infiltrating eosinophils and epithelial cells. Approximately 87% of eosinophils observed in the challenged epithelium were associated with such loss of E-cadherin immunoreactivity. These results suggest that the intimate epithelial cell contact mediated by E-cadherin is loosened as a consequence of eosinophil infiltration, which may trigger the initial step of subsequent epithelial destruction in allergic states.
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Yamada K, Mori A, Seki M, Kimura J, Yuasa S, Matsuura Y, Miyamura T. Critical point mutations for hepatitis C virus NS3 proteinase. Virology 1998; 246:104-12. [PMID: 9656998 DOI: 10.1006/viro.1998.9184] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The hepatitis C virus NS3 proteinase plays an essential role in processing of HCV nonstructural precursor polyprotein. To detect its processing activity, we developed a simple trans-cleavage assay. Two recombinant plasmids expressing the NS3 proteinase region and a chimeric substrate polyprotein containing the NS5A/5B cleavage site between maltose binding protein and protein A were co-introduced into Escherichia coli cells. The proteinase processed the substrate at the single site during their polyprotein expression. Deletion analysis indicated that the functionally minimal domain of the NS3 proteinase was composed of 146 amino acids, 1059 to 1204. We isolated several cDNA clones encoding the functional domain of the NS3 proteinase from the sera of patients chronically infected with HCV and determined their proteinase activity by this trans-cleavage assay. Both active and inactive clones existed in the same patients. Comparative sequence analyses of these clones suggested that certain point mutations seemed to be related to the loss of proteolytic activity. This was confirmed by back mutation experiments. Among the critical mutations, Pro-1168 to Thr and Arg-1135 to Gly were intriguing. These amino acids, which are situated near the oxyanion hole, seem to be essential for maintaining the conformation of the active center of the NS3 proteinase.
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Yuasa S, Takahashi N, Shoji T, Uchida K, Kiyomoto H, Hashimoto M, Fujioka H, Fujita Y, Hitomi H, Matsuo H. A simple and early prognostic index for acute renal failure patients requiring renal replacement therapy. Artif Organs 1998; 22:273-8. [PMID: 9555958 DOI: 10.1046/j.1525-1594.1998.06025.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent advances in technology have not substantially changed the high mortality rate associated with acute renal failure (ARF). To obtain a simple, valid prognostic index, we retrospectively evaluated the relative importance of demographic data, causes (acute insults) of renal failure, and comorbid clinical conditions for the outcome in 102 ARF patients who received renal replacement therapy with an overall mortality rate of 65% (66 of 102). There were no significant differences between survivors and nonsurvivors in age and gender. Mortality according to acute insults was similar to that of the whole population studied. Of the 10 clinical conditions at the time of the first renal replacement therapy, mechanical ventilation (p = 0.0002), cardiac failure (p = 0.0006), hepatic failure (p = 0.003), central nervous system dysfunction (p = 0.005), and oliguria (p = 0.04) were found to be significantly related to mortality by univariate analysis. Furthermore, multivariate analysis demonstrated that only mechanical ventilation, cardiac failure, and hepatic failure were significant risk factors. Survival was directly related to the number of significant variables in univariate analysis: zero, 89% (8 of 9); one, 62% (21 of 34); two, 19% (5 of 27); three, 10% (2 of 20); four, 0% (0 of 8); five, 0% (0 of 4). This simple and early prognostic index, derived from the assessment of clinical conditions which were easily determined at the patient's bedside, could be useful for outcome prediction in ARF patients requiring renal replacement therapy.
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Morii K, Kishi F, Morishita H, Okushin H, Yuasa S, Sato S, Nakashima A, Nabeyama A. [A case of hepatectomy for biloma after transcatheter arterial chemoembolization]. NIHON SHOKAKIBYO GAKKAI ZASSHI = THE JAPANESE JOURNAL OF GASTRO-ENTEROLOGY 1998; 95:337-41. [PMID: 9591411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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92
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Kubota T, Furukawa T, Tanino H, Oura S, Murata H, Yuasa S, Morita K, Ueno J, Kozakai R, Yano T. Pirarubicin might partly circumvent the P-glycoprotein-mediated drug resistance of human breast cancer tissues. Anticancer Res 1998; 18:967-72. [PMID: 9615748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Anthracyclines are the first line antitumor agents against breast cancer, and P-glycoprotein (Pgp) is thought to be the main resistance mechanism against these agents. We have evaluated the chemosensitivity of fresh surgical specimens of breast cancer and compared them with their Pgp-expression. MATERIALS AND METHODS The in vitro chemosensitivity of 65 surgical specimens obtained from 63 patients with advanced breast cancer was assessed by the histoculture drug response assay (HDRA) using doxorubicin (DXR), pirarubicin [(2"R)-4'-tetrahydropyranyladriamycin: THP], and epirubicin (EPIR). Breast cancer tissues were plated onto collagen gel matrix and incubated with 15 micrograms of DXR or EPIR, or 17 micrograms of THP per ml for 7 days with MTT assessed at the endpoint. The efficacy of the agents was evaluated by the inhibition index (I.I.) of the optical density detected by ELISA reader. RESULTS When 60% or more I.I. was regarded as in vitro sensitive at each cut-off concentration of the drugs, the overall efficacy rates were 60.7%, 48.6%, and 78.6% for DXR, EPIR, and THP, respectively. Fifty-one surgical specimens were evaluated for the immunohistochemical analysis of Pgp and the correlation between the sensitivity to anthracyclines and the expression of Pgp was compared. Pgp was expressed in 23.5% (12/51) specimens and the efficacy of anthracyclines was reduced in Pgp-positive breast cancer tissues, although this reduction was low in THP with a statistically significant difference when comparing with DXR and EPIR. CONCLUSION The present results suggest that THP might partly circumvent the mdr1/PgP-mediated drug resistance mechanism in human breast cancer tissue and would have some different antitumor spectra on breast cancer comparing with DXR and EPIR.
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Igakura T, Kadomatsu K, Kaname T, Muramatsu H, Fan QW, Miyauchi T, Toyama Y, Kuno N, Yuasa S, Takahashi M, Senda T, Taguchi O, Yamamura K, Arimura K, Muramatsu T. A null mutation in basigin, an immunoglobulin superfamily member, indicates its important roles in peri-implantation development and spermatogenesis. Dev Biol 1998; 194:152-65. [PMID: 9501026 DOI: 10.1006/dbio.1997.8819] [Citation(s) in RCA: 210] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Basigin is a highly glycosylated transmembrane protein with two immunoglobulin-like domains. We generated mutant mice lacking the basigin gene (Bsg) by gene targeting. Bsg (-/-) embryos developed normally during preimplantation stages. However, the majority of Bsg (-/-) embryos died around the time of implantation. At this time, basigin mRNA was strongly expressed in the trophectoderm, embryo proper, and uterine endometrium of Bsg (+/+) mice. These results suggest that basigin is involved in intercellular recognition during implantation. Embryos which survived the critical period yielded Bsg (-/-) mutant mice. Half of the mutant mice died before 1 month after birth, due to interstitial pneumonia. The surviving adult mutant mice were small and sterile. Spermatogenesis was arrested in the mutant mice. Most of the spermatocytes in the Bsg (-/-) mouse were arrested and degenerated at the metaphase of the first meiosis, and only a small number differentiated to step 1 spermatids. In the female mutants, the ovaries and genital tract were morphologically normal, and the defect was probably in the capability of implantation of the uterus. In conclusion, basigin is an important cell-surface molecule involved in early embryogenesis and reproduction.
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94
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Fan QW, Yuasa S, Kuno N, Senda T, Kobayashi M, Muramatsu T, Kadomatsu K. Expression of basigin, a member of the immunoglobulin superfamily, in the mouse central nervous system. Neurosci Res 1998; 30:53-63. [PMID: 9572580 DOI: 10.1016/s0168-0102(97)00119-3] [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: 02/07/2023]
Abstract
Basigin (Bsg) is a transmembrane glycoprotein belonging to the immunoglobulin superfamily. Chicken Bsg (HT7/neurothelin/ 5A11) is expressed in neuroblasts, but disappears from neurons after a specific stage of cytodifferentiation, and becomes restrictedly expressed in the capillary endothelium in the adult brain. We show herein by means of in situ hybridization that Bsg mRNA was expressed in neuroblasts in 13.5 day old mouse embryos. In the adult mouse, Bsg was differentially expressed in subregions of the brain. Strong Bsg expression was detected in the limbic system, including the olfactory system, hippocampal formation, septal area, amygdala, thalamic anterior nuclei, hypothalamus, mesencephalic tegmentum, entorhinal cortex, and cingulate gyrus. Bsg was also intensely expressed in the retinal neuronal layers, the Vth layer of the cerebral neocortex, Purkinje cells of the cerebellum, several nuclei of the brain stem, and the gray matter of the spinal cord. Although in situ hybridization showed a weak signal in the brain capillary endothelium, protein expression of Bsg was strong enough to be detected by immunohistochemistry. Northern blot analysis confirmed the strong expression of Bsg in the central nervous system. Taking into account that Bsg knockout mice exhibit abnormalities in behavior, but a normal blood-brain barrier function, the present findings suggest that Bsg functions actively in neuronal interactions in the central nervous system.
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MESH Headings
- Animals
- Antigens, CD
- Antigens, Neoplasm
- Antigens, Surface/analysis
- Antigens, Surface/biosynthesis
- Avian Proteins
- Basigin
- Blood Proteins
- Brain/embryology
- Brain/growth & development
- Brain/metabolism
- Capillaries/embryology
- Capillaries/metabolism
- Cerebrovascular Circulation
- Chickens
- Embryo, Mammalian
- Embryo, Nonmammalian
- Gene Expression Regulation, Developmental
- In Situ Hybridization
- Membrane Glycoproteins/analysis
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/deficiency
- Mice
- Mice, Knockout
- Neurons/metabolism
- Organ Specificity
- RNA, Messenger/biosynthesis
- Spinal Cord/embryology
- Spinal Cord/growth & development
- Spinal Cord/metabolism
- Stem Cells/metabolism
- Transcription, Genetic
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95
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Kajino K, Kamiya N, Yuasa S, Takahara T, Sakurai J, Yamamura KI, Hino O. Evaluation of anti-hepatitis B virus (HBV) drugs using the HBV transgenic mouse: application of the semiquantitative polymerase chain reaction (PCR) for serum HBV DNA to monitor the drug efficacy. Biochem Biophys Res Commun 1997; 241:43-8. [PMID: 9405231 DOI: 10.1006/bbrc.1997.7766] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
For evaluation of anti-hepatitis B virus (HBV) drugs, we have employed the HBV transgenic mouse in which virion-like particles can be assayed in the serum. Bispivaloyloxymethyl-9-(2-phosphonylmethoxyethyl)-adenine [bis (POM) PMEA] 100 mg/kg/day, 2',3'-dideoxy-3'-thiacytidine [(+-)-BCH189] 200 mg/kg/day and a placebo were orally administered to mice twice a day for 14 days. Anti-viral effects were monitored by checking the levels of serum HBV DNA by the semiquantitative polymerase chain reaction, HBsAg and HBeAg by enzyme immunoassay, and replicative intermediates in the liver by Southern blotting. As expected, decrease from the 10(0.5) to 10(3) copies of HBV DNA per microl of sera detected before the treatment to the undetectable level was evident for all five animals treated with bis(POM) PMEA 100 mg/kg/day. However (+-)-BCH189 200 mg/kg/day, which is known to act as the inhibitor of reverse transcriptase for HBV or HIV in vivo and in vitro, did not suppress HBV DNA levels in the transgenic mouse. Thus, we were able to detect the effects of anti-HBV drugs semi-quantitatively, and confirm differences in drug efficacy.
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96
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Yuasa S, Kishi F, Morii K, Morishita H, Okushin H. [Clinical study of the application of the concepts of systemic inflammatory response syndrome (SIRS) in liver cirrhosis with or without hepatocellular carcinoma with upper gastrointestinal hemorrhage--a retrospective study]. NIHON SHOKAKIBYO GAKKAI ZASSHI = THE JAPANESE JOURNAL OF GASTRO-ENTEROLOGY 1997; 94:643-8. [PMID: 9391325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The retrospective study was aimed at assessing the usefulness of the application of the criteria of SIRS for identifying a subset of patients with higher mortality in 22 cases (21 patients) of liver cirrhosis with upper gastrointestinal hemorrhage (GIH) and 16 cases (14 patients) of liver cirrhosis with hepatocellular carcinoma with upper GIH. The following results were obtained; (1) The incidence of SIRS on upper GIH was 66%. (2) The mortality rate in patients with SIRS on GIH was significantly higher than in patients with non-SIRS on GIH in 60 days after GIH was significantly higher than in patients with non-SIRS on GIH in 60 days after GIH (50% vs. 8%; p < 0.01). (3) The rate of patients who met four criteria of SIRS on GIH or during admission and of patients whose durations of SIRS was over 5 days was significantly higher in the died patients with SIRS on GIH than in the survived patients with SIRS on GIH (67% vs. 0%; p < 0.01, 67% vs. 0%; p < 0.01, respectively). These results suggested that the application of the criteria of SIRS was useful for identifying a subset of patients with higher mortality in chronic liver disease with GIH.
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97
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Li X, Yuasa S, Hitomi H, Hashimoto M, Fujioka H, Kiyomoto H, Uchida K, Shoji T, Takahashi N, Matsuo H. [Mechanism mediating hypertension induced by chronic inhibition of nitric oxide synthesis]. NIHON JINZO GAKKAI SHI 1997; 39:718-27. [PMID: 9396239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Although the inhibition of nitric oxide (NO) synthesis is known to induce systemic hypertension, the underlying mechanisms mediating this type of hypertension are incompletely understood. In the present study we investigated the influence of sodium intake on the pressor effect of long-term administration of the NO synthesis inhibitor, NG-nitro-L-arginine methyl ester (L-NAME, 16 mg/dl in drinking fluid for 8 weeks), in conscious Sprague-Dawley rats. Urinary excretion rates of catecholamine during NO synthesis inhibition were also examined. Long-term administration of L-NAME produced a sustained elevation in tail-cuff pressure without altering urine flow, or sodium excretion rate. L-NAME-induced hypertension was accompanied by a decreased urinary excretion of the stable NO metabolites, NO2- and NO3-, and was aggravated when rats drank 0.9% saline in place of tap water. Thus, inhibition of NO synthesis resulted in a rightward shift of the pressure natriuresis relationship and a significant decrease in the slope of this relationship. Urinary excretion of epinephrine and norepinephrine, but not that of dopamine, in L-NAME-treated rats significantly increased within the first week of the study when compared with those observed in control rats. A natriuretic index of the sympathetic nervous system, the ratio of dopamine to norepinephrine excretion, was significantly less in L-NAME-treated rats than in control rats. After 8-week treatment with L-NAME, renal morphologic evaluation revealed significant narrowing and obliteration of the arterioles. L-arginine (2 g/dl in drinking fluid) completely reversed the elevation of blood pressure as well as the decrease in urinary NO2- and NO3- excretion and the increased urinary excretion of catecholamines associated with L-NAME treatment after 3 weeks of concomitant administration. These results suggest that the inhibition of chronic NO synthesis produces sodium-sensitive hypertension and that changes in sympathetic nerve activity may, at least in part, contribute to the sodium sensitivity in this type of hypertension.
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98
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Yuasa S, Fukuhara T, Isoyama M, Tanaka M, Shimada A. Resolution of DL-amino acids on a native cellulose column and a plausible mechanism for their resolution. Biomed Chromatogr 1997; 11:276-9. [PMID: 9376708 DOI: 10.1002/(sici)1099-0801(199709)11:5<276::aid-bmc696>3.0.co;2-g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have studied the resolution of DL-amino acids on a native cellulose column. All the DL-amino acids related to protein and their 16 DNP-DL-amino acids were separated. The resolution capability depends mainly upon the bulkiness of the side group attached to the alpha-carbon, but also on structural and functional interaction of amino acid with cellulose. We propose a plausible resolution mechanism that is thought to be governed by a so-called key and lock relation between an amino acid and cellulose. Then, the affinity of each enantiomer for cellulose was calculated based on the resolution factor, which was known to be some 10(-2) -10(-3) eV.
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99
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Taniguchi M, Yuasa S, Fujisawa H, Naruse I, Saga S, Mishina M, Yagi T. Disruption of semaphorin III/D gene causes severe abnormality in peripheral nerve projection. Neuron 1997; 19:519-30. [PMID: 9331345 DOI: 10.1016/s0896-6273(00)80368-2] [Citation(s) in RCA: 455] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The molecules of the collapsin/semaphorin gene family have been thought to play an essential role in axon guidance during development. Semaphorin III/D is a member of this family, has been shown to repel dorsal root ganglion (DRG) axons in vitro, and has been implicated in the patterning of sensory afferents in the spinal cord. Although semaphorin III/D mRNA is expressed in a wide variety of neural and nonneural tissues in vivo, the role played by semaphorin III/D in regions other than the spinal cord is not known. Here, we show that mice homozygous for a targeted mutation in semaphorin III/D show severe abnormality in peripheral nerve projection. This abnormality is seen in the trigeminal, facial, vagus, accessory, and glossopharyngeal nerves but not in the oculomotor nerve. These results suggest that semaphorin III/D functions as a selective repellent in vivo.
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100
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Yuasa S. [Preoperative autologous transfusion--its methods and clinical usefulness]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1997; 55:2399-405. [PMID: 9301307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In spite of continuing development in transfusion medicine, homologous transfusion accompanies risks and problems, such as viral infection, alloimmunization, transfusion associated GVHD and immunosuppressive reactions. To avoid these risks of homologous transfusion, autologous blood transfusion has been introduced as the safest blood transfusion. Here, methods of predeposit autologous blood transfusion and its clinical usefulness are described. There are two methods for predeposit autologous transfusion; Liquid preservation and frozen preservation. The merit of the former is easy and economical, but 3 units (1200 ml) will be maximum volume to collect in 3 weeks before surgery. While frozen preservation, patient can predeposit the necessary amount of blood without affecting their preoperative condition, as we can set the intervals of blood collections more than 3 weeks, and blood can be stored up to 10 years. However this method requires equipment and cost more.
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