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Imai M, Goepfert C, Kaczmarek E, Robson SC. CD39 modulates IL-1 release from activated endothelial cells. Biochem Biophys Res Commun 2000; 270:272-8. [PMID: 10733939 DOI: 10.1006/bbrc.2000.2410] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The activation of endothelial cells (EC) and monocyte-macrophages (Mφ) by lipopolysaccharide (LPS) is considered an important element of the vascular injury observed in endotoxemia. Interleukin-1 (IL-1) beta release from Mφ in response to LPS, appears to be mediated by the autocrine/paracrine release of ATP via P2X7 receptor activation. In EC, similar nucleotide-mediated signaling pathways may be influenced by high levels of expression of CD39, the vascular nucleoside triphosphate diphosphohydrolase (NTPDase; ENTPD I). To determine whether CD39 modulates ATP-mediated release of IL-1 from EC, we stimulated human EC with LPS and measured levels of ATP secretion and IL-1 release. LPS triggered ATP secretion from EC that was soon followed by IL-1alpha release. Overexpression of CD39 following infection with recombinant CD39 adenoviral vectors (AdCD39) abrogated the initial phase of ATP secretion and inhibited IL-1alpha release; comparable results were obtained with soluble NTPDase. These data demonstrate that CD39/NTPDase modulates IL-1alpha release from LPS stimulated human EC.
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152
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Furuya Y, Katayama T, Hara M, Yoshida Y, Imai M, Hagiwara T. Occurrence of scrub typhus (Tsutsugamushi) in Kanagawa Prefecture and types of Orientia tsutsugamushi involved. Jpn J Infect Dis 2000; 53:77-8. [PMID: 10871922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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153
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Usuku S, Noguchi Y, Sakamoto M, Sagara H, Sudo K, Kondo M, Imai M. [HIV-1 (human immunodeficiency virus type 1) mutant strain associated with zidovudine resistance detected from a Japanese patient with primary HIV-1 infection]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 2000; 74:360-4. [PMID: 10835842 DOI: 10.11150/kansenshogakuzasshi1970.74.360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Sequences of HIV-1 pol gene were determined by direct sequencing from a Japanese patient with primary HIV-1 infection. The patient did not receive antiretroviral therapies. However we observed a HIV-1 mutant strain associated with zidovudine (ZDV) resistance. The patient had both the codon 70 and the codon 215 amino acid substitutions in the RT region. Our data indicated that the patient was infected with a HIV-1 mutant strain associated with ZDV resistance and this is the first report in Japan.
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154
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Satoh J, Kutsuwada K, Ohki G, Imai M, Kobayashi M, Suzuki M. Cyclic AMP stimulates the gene expression of a non-selective cation channel, mNSC1, in pancreatic beta-cell line, MIN6. Mol Cell Endocrinol 2000; 160:165-71. [PMID: 10715550 DOI: 10.1016/s0303-7207(99)00214-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Mouse non-selective cation channel 1 (mNSC 1) cDNA from mouse pancreatic beta-cell line, MIN6, have recently been cloned. Since the number of non-selective cation channel in pancreatic duct cells has been reported to increase 9-fold in 5 h incubation with cAMP, the effect of cAMP on the gene expression of mNSC1 in MIN6 cells was examined. Dibutyryl cAMP (db-cAMP) was shown to increase the level of the mRNA by reverse transcription-polymerase chain reaction (RT-PCR). The copy number of the mRNA was increased 4-fold in 6 h incubation with db-cAMP by competitive PCR. Western blot analysis also indicated a 4-fold increase in the quantity of the newly synthesized protein in 9 h incubation with db-cAMP. Experiments with 5'-flanking region and with a transcriptional inhibitor suggested that db-cAMP affected transcription, and protected the mRNA from its degradation as well. It is concluded that the expression of mNSC1 is indeed increased by cAMP in the pancreatic beta-cells.
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155
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Tsuruoka S, Sugimoto K, Muto S, Nomiyama K, Fujimura A, Imai M. Acute effect of cadmium-metallothionein on glucose and amino acid transport across the apical membrane of the rabbit proximal tubule perfused in vitro. J Pharmacol Exp Ther 2000; 292:769-77. [PMID: 10640317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Acute as well as chronic exposure of cadmium (Cd) leads to proximal tubule injury. The exact cellular mechanism of this disorder and whether there is a contribution of cadmium-metallothionein (Cd-MT), a binding protein of Cd, remain unclear. We perfused isolated S2 segments of rabbit nephron, and the deflections of transmural voltage (DeltaV(t)) and apical membrane voltage (DeltaV(a)) on elimination of glucose or alanine from the perfusate were measured for the parameters of activity of Na(+)-glucose and Na(+)-amino acid cotransporters. The effects of Cd-MT or CdCl(2) to either bath or lumen for 10 min on these parameters were examined. We also measured the lumen-to-bath [(14)C]glucose flux. Addition of Cd-MT to lumen suppressed glucose- or alanine-dependent DeltaV(t) and DeltaV(a), as well as baseline V(t) and basolateral membrane voltage (V(b)), at approximately 10 min. [(14)C]glucose flux was inhibited by Cd-MT to lumen. The effects of Cd-MT to bath and CdCl(2) to either lumen or bath were 100-fold less potent than that of Cd-MT to lumen. Luminal Cd-MT immediately suppressed the glucose-dependent DeltaV(a), whereas the baseline V(a) and V(t) were unchanged. The early effect of luminal Cd-MT was simulated by addition of 10(-4) M phloretin. Addition of 10(-4) M ouabain to the bath simulated the later effect of Cd-MT. The protection of SH group by dithiothreitol prevented the early effect of Cd-MT, but not the later effect. We concluded that Cd-MT initially acts directly on Na(+)-glucose and Na(+)-amino acid cotransporters from the lumen by attacking SH group, followed by the later inhibition of Na(+)-K(+)-ATPase after entering the cell from the apical membrane.
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156
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Kamao M, Tsugawa N, Nakagawa K, Kawamoto Y, Fukui K, Takamatsu K, Kuwata G, Imai M, Okano T. Absorption of calcium, magnesium, phosphorus, iron and zinc in growing male rats fed diets containing either phytate-free soybean protein or soybean protein isolate or casein. J Nutr Sci Vitaminol (Tokyo) 2000; 46:34-41. [PMID: 10868351 DOI: 10.3177/jnsv.46.34] [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: 11/27/2022]
Abstract
The effect of dietary phytate-free soybean protein (PFS) on intestinal mineral absorption and retention was examined in growing male rats using a three-day mineral balance technique. The rats were fed diets containing PFS, soybean protein isolate (SPI) or casein at a 20% level for 5 wk. Total calcium (Ca), magnesium (Mg), phosphorus (P), iron (Fe) and zinc (Zn) contents in diets were adjusted to 0.35, 0.05, 0.7, 0.0035 and 0.003%, respectively, by supplementation of the diet with their salts. Mineral absorption and retention ratios in rats fed the PFS diet were significantly higher than those in rats fed either the SPI or casein diet. These results suggest that PFS may be a promising dietary protein source for improving the mineral bioavailability in humans.
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157
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Koziak K, Kaczmarek E, Kittel A, Sévigny J, Blusztajn JK, Schulte Am Esch J, Imai M, Guckelberger O, Goepfert C, Qawi I, Robson SC. Palmitoylation targets CD39/endothelial ATP diphosphohydrolase to caveolae. J Biol Chem 2000; 275:2057-62. [PMID: 10636909 DOI: 10.1074/jbc.275.3.2057] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ectonucleotidases influence purinergic receptor function by the hydrolysis of extracellular nucleotides. CD39 is an integral membrane protein that is a prototype member of the nucleoside 5'-triphosphate diphosphohydrolase family. The native CD39 protein has two intracytoplasmic and two transmembrane domains. There is a large extracellular domain that undergoes extensive glycosylation and can be post-translationally modified by limited proteolysis. We have identified a potential thioester linkage site for S-acylation within the N-terminal region of CD39 and demonstrate that this region undergoes palmitoylation in a constitutive manner. The covalent lipid modification of this region of the protein appears to be important both in plasma membrane association and in targeting CD39 to caveolae. These specialized plasmalemmal domains are enriched in G protein-coupled receptors and appear to integrate cellular activation events. We suggest that palmitoylation could modulate the function of CD39 in regulating cellular signal transduction pathways.
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158
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Hayashi T, Kondo M, Shimazaki M, Ueda M, Imai M. [Studies on centrifuge-concentration method of pooled samples for HIV screening test by RT-PCR]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 2000; 74:82-3. [PMID: 10695299 DOI: 10.11150/kansenshogakuzasshi1970.74.82] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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159
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Iijima H, Iida T, Imai M, Gohdo T, Tsukahara S. Optical coherence tomography of orange-red subretinal lesions in eyes with idiopathic polypoidal choroidal vasculopathy. Am J Ophthalmol 2000; 129:21-6. [PMID: 10653408 DOI: 10.1016/s0002-9394(99)00253-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE To study the cross-section images of orange-red lesions in eyes with idiopathic polypoidal choroidal vasculopathy and compare their protrusions quantitatively with those of serous retinal pigment epithelium detachment. METHODS Optical coherent tomography images scanning remarkable orange-red lesions in eyes with idiopathic polypoidal choroidal vasculopathy and serous retinal pigment epithelium detachment in age-related macular degeneration or central serous chorioretinopathy were prospectively recorded. The correlation between the base diameter and the height of the lesions was analyzed. RESULTS Optical coherence tomography images show prominent anterior protrusion of the orange-red lesions. The ratio of the height to the base diameter of the orange-red lesions in eyes with idiopathic polypoidal choroidal vasculopathy is 0.32+/-0.05, and it is significantly larger than lesions in eyes with serous retinal pigment epithelium detachment (0.18+/-0.05, P< .001). CONCLUSION The orange-red lesions in eyes with idiopathic polypoidal choroidal vasculopathy have a more sharply peaked shape than serous retinal pigment epithelium detachment as a subretinal structure, suggesting polypoidal vascular lesions in eyes with idiopathic polypoidal choroidal vasculopathy are situated beneath the Bruch membrane and covered anteriorly with both the retinal pigment epithelium and the Bruch membrane.
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160
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Mitamura K, Yamazaki M, Kimura K, Sugaya N, Nirasawa M, Takahashi K, Shimizu H, Hirai Y, Watanabe S, Imai M. [Evaluation of the rapid detection test for influenza A and B viruses using neuraminidase activity]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 2000; 74:12-6. [PMID: 10695289 DOI: 10.11150/kansenshogakuzasshi1970.74.12] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The ZstatFlu test (ZymeTx, USA) is a rapid detection kit for influenza A and B viruses. This test is based upon the reaction between viral neuraminidase from influenza viruses and a chromogenic substrate. The clinical performance of the ZstatFlu test was determined by comparison with viral isolation in cell culture. A total of 176 respiratory specimens from 172 pediatric patients with influenza like illnesses during the 1998/99 season were tested. Influenza viruses were recovered from 97 specimens (type A: 6, type B: 91) in cell culture. ZstatFlu demonstrated 67.4% sensitivity (29/43) and 62.7% specificity (37/59) for throat swabs. Of the 22 ZstatFlu-positive, culture-negative throat swabs tested by RT-PCR, 18 were positive by RT-PCR. ZstatFlu showed 48.1% sensitivity (26/54) and 90.0% specificity (18/20) for nasopharyngeal aspirates. Of the two ZstatFlu-positive, culture-negative nasopharyngeal aspirates tested by HI titer of paired sera, one showed a 4-fold increase of HI titer. Nasopharyngeal aspirates therefore showed lower sensitivity than throat swabs at this test, different from EIA test kits such as Directigen FluA or FLU OIA. Overall, only 5 specimens were false positive by the ZstatFlu test. Therefore, this test demonstrated high specificity and positive predictive value. In conclusion, the ZstatFlu test is useful for the rapid detection of influenza A and B viruses to identify patients who need antiviral treatment.
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161
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Ohta R, Imai M, Fukuoka Y, Miwa T, Okada N, Okada H. Characterization of mouse DAF on transfectant cells using monoclonal antibodies which recognize different epitopes. Microbiol Immunol 1999; 43:1045-56. [PMID: 10609614 DOI: 10.1111/j.1348-0421.1999.tb01234.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Several membrane proteins prevent host cells from homologous complement attack. In humans, one such protein, decay-accelerating factor (DAF), exists as two isoforms, a GPI anchored form and a secreted form, which are generated by alternative splicing. DAF in mouse is also expressed as two isoforms, a GPI anchored form (GPI-DAF) and a transmembrane form (TM-DAF), which are produced from two separate genes. In this study, we transfected cDNA of mouse GPI-DAF or TM-DAF into Chinese hamster ovary (CHO) cells. Both isoforms of DAF on CHO cells were shown to regulate mouse complement C3 deposition mediated by the classical and alternative pathways and the inhibitory activity of both isoforms was species restricted. The two mouse DAF isoforms were effective against rat complement but not against human and guinea pig complement. Furthermore, we produced hamster mAbs to mouse DAF using GPI-DAF transfectant cells and established seven unique mAbs (RIKO-1-7). Western blotting analysis using RIKO-3, which reacts with both GPI-DAF and TM-DAF, and RIKO-4, which is an anti-GPI-DAF specific mAb, indicated that GPI-DAF was expressed on erythrocytes, spleen and testis, and that TM-DAF was expressed only in testis.
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162
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Watanabe S, Shimizu H, Kawakami C, Imai M. [Evaluation of an optical immunoassay test for rapid detection of influenza A and B viral antigen]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 1999; 73:1199-204. [PMID: 10655680 DOI: 10.11150/kansenshogakuzasshi1970.73.1199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
An optical immunoassay test, FLU OIA (BIOSTAR, USA), was evaluated for the diagnosis of influenza viral infection. The reactivity of the FLU OIA test was evaluated using 42 influenza strains (25 human influenza A, 12 human influenza B, 2 swine influenza A and 3 avian influenza A strains). The FLU OIA test showed positive results for all influenza strains. There was no evidence that cross-reactivity occurred with non-influenza viruses. The detection limit of the FLU OIA test was found to be 3.0-6.5 x 10(4) pfu/assay for human influenza A and B strains. The sensitivity and specificity of the FLU OIA test compared to isolation in cell culture was 89.7% and 76.0% for testing of 54 nasopharyngeal aspirate specimens. The FLU OIA test is rapid and easy for the detection of influenza A and B viral antigen and provide a valuable tool for the rapid diagnosis of influenza viral infection.
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163
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Hisamatsu K, Ueeda M, Ando M, Koike K, Matsuo N, Matsu-ura K, Ueda H, Hirohata M, Imai M. Peripheral arterial coil embolization for hepatic arteriovenous malformation in Osler-Weber-Rendu disease; useful for controlling high output heart failure, but harmful to the liver. Intern Med 1999; 38:962-8. [PMID: 10628935 DOI: 10.2169/internalmedicine.38.962] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 55-year-old Japanese housewife, who had Osler-Weber-Rendu disease, was admitted to our hospital because of frequent epistaxis and worsening exertional dyspnea. The computed tomography and hepatic arteriography revealed large hepatic arteriovenous malformation, which was considered to be the leading cause of her high output heart failure. Two series of hepatic arterial coil embolization procedures were performed to reduce hepatic shunt flow. They temporarily improved her cardiac condition, but gradually induced progressive hepatic failure due to intrahepatic cholangitis. Hepatic dysfunction restricted her quality of life and lead to a fatal clinical course one year after the second coil embolization.
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164
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Imai M, Sudo K, Hayashi T, Kondo M. [Kinetic analysis of anti-HIV titer in early stage of HIV infection--a new testing strategy to differentiate early HIV infection individuals from false positive cases]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 1999; 73:1183-6. [PMID: 10655677 DOI: 10.11150/kansenshogakuzasshi1970.73.1183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We analyzed the anti-HIV antibody titer by particle agglutination (PA) on 11 HIV seroconversion panels. PA titer increased very rapidly and the titer went up to 1,000 or more within 18.2 days after seroconversion. The results suggest that one to two weeks of duration will be enough to differentiate persons at the early stage of HIV infection from individuals with HIV screening test initially reactive but false positive. In Japan, HIV prevalence is very low and the majority of the HIV screening test-positive (reactive) cases turned out to be false positive. This HIV testing strategy (one to two weeks interval bleeding) will be very practical and useful to differentiate early stage of HIV infection cases from the majority of false positive cases.
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165
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Imai M, Iijima H, Gotoh T, Tsukahara S. Optical coherence tomography of successfully repaired idiopathic macular holes. Am J Ophthalmol 1999; 128:621-7. [PMID: 10577532 DOI: 10.1016/s0002-9394(99)00200-7] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PURPOSE To present the cross-sectional retinal imaging results of optical coherence tomography in eyes with successfully repaired idiopathic macular hole and their relevance to visual recovery. METHODS We studied 33 eyes with successful repair of an idiopathic macular hole through vitrectomy and fluid-gas exchange from 32 patients (11 men and 21 women) with ages ranging from 48 to 78 years, with a median age of 66 years. Preoperative conditions in eyes with primary surgery disclosed nine eyes with stage 2, 14 eyes with stage 3, and four eyes with stage 4 macular hole. An additional six eyes underwent a second surgery because the previous surgery was unsuccessful. Measurement of best-corrected visual acuity, slit-lamp biomicroscopy with fundus contact lens, fundus photographs, and optical coherence tomographic examination were performed between 6 and 9 months after surgery in 29 eyes and between 15 and 36 months after surgery in four eyes. RESULTS Optical coherence tomographic images of the repaired macular holes were categorized into three patterns. U-type (normal foveal contour; 13 eyes) showed mildly to moderately backscattering layers with a smooth circular surface covering retinal pigment epithelium and choriocapillaris layers. In eyes with V-type (steep foveal contour; 13 eyes), the retinal pigment epithelium and choriocapillaris layers were covered with moderately backscattering layers with a notch. W-type (foveal defect of neurosensory retina; seven eyes) showed abruptly or gradually terminating sensory retinal layers to expose the surface of the retinal pigment epithelium and choriocapillaris layers. Postoperative acuity was well correlated with these patterns of optical coherence tomographic images. CONCLUSION Assessment of successfully repaired idiopathic macular holes with optical coherence tomographic images provides a useful correlation with postoperative visual recovery.
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166
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Imai M, Takigami K, Guckelberger O, Enjyoji K, Smith RN, Lin Y, Csizmadia E, Sévigny J, Rosenberg RD, Bach FH, Robson SC. Modulation of nucleoside [correction of nucleotide] triphosphate diphosphohydrolase-1 (NTPDase-1)cd39 in xenograft rejection. Mol Med 1999; 5:743-52. [PMID: 10656876 PMCID: PMC2230486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
BACKGROUND There is increasing evidence showing that extracellular nucleosides [corrected] may be important mediators of vascular inflammation. Nucleoside [corrected] triphosphate diphosphohydrolase-1 (NTPDase-1, identical to CD39), the major vascular endothelial ectonucleotidase, is responsible for the hydrolysis of both extracellular ATP and ADP in the blood plasma to AMP. Studies were therefore conducted to evaluate the role of vascular NTPDase-1/cd39 in modulating platelet activation and vascular injury in cardiac xenografts. MATERIALS AND METHODS Cardiac xenografts from both wild-type and cd39 knockout mice (C57BL/6 x 129 Svj) were transplanted into Lewis rats. Alterations in cd39 mRNA transcripts and NTPDase activity expression were evaluated in wild-type grafts in untreated rats and then following complement depletion and immunosuppression. Rejection responses were studied with both mutant and wild-type grafts in the following models: presensitization with or without complement depletion, complement depletion alone, and with chronic immunosuppression to induce long-term graft survival. RESULTS NTPDase biochemical activity in wild-type xenografts rapidly decreased after transplantation but soon rebounded with graft survival. Elevated levels of cd39 mRNA with associated increases in NTPDase activity were observed in all long-term surviving wild-type grafts. Hyperacute xenograft rejection times were comparable in wild-type and mutant grafts but cd39-deficient grafts were subject to more rapid rejection and exhibited pronounced vascular injury in complement-depleted, presensitized rats. The cd39-deficient grafts in immunosuppressed recipients were subject to increased intravascular platelet sequestration and fibrin deposition; this resulted in focal myocardial infarction in long-term surviving mutant xenografts. CONCLUSIONS Augmentation of NTPDase-1 activity may be an important adaptive response for graft survival. Our results suggest that NTPDase-1/cd39 influences pathways of vascular injury in cardiac xenografts.
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MESH Headings
- Adenosine Triphosphatases
- Animals
- Antigens, CD/analysis
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Apyrase/analysis
- Apyrase/genetics
- Apyrase/metabolism
- Blotting, Western
- Gene Expression Regulation, Enzymologic
- Graft Rejection/enzymology
- Graft Survival
- Heart Transplantation
- Immunohistochemistry
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred Strains
- Mice, Knockout
- Mice, Mutant Strains
- P-Selectin/analysis
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred Lew
- Transplantation, Heterologous
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167
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Miyoshi T, Ooki G, Murata M, Hayakawa H, Tomita K, Imai M, Suzuki M. Expression of an mNSC1 in mammalian cells. Biochem Biophys Res Commun 1999; 265:13-7. [PMID: 10548483 DOI: 10.1006/bbrc.1999.1622] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have cloned a cDNA inducing a cation-permeable current (mNSC1) from pancreatic beta-cells, which shows niflumate-sensitive current in Xenopus oocytes. To elucidate the expression in mammalian cells, mNSC1 was expressed in CHO cells. The reversal potential by mNSC1 was shifted toward positive which was significantly reversed by flufenamic acid. Single-channel analysis showed a characteristic of a Ca-activated nonselective cation channel. Therefore, we may conclude that mNSC1 expresses a fenamates-sensitive cation channel, inducing membrane depolarization in a mammalian cell.
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168
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Takahashi M, Taniguchi J, Muto S, Tsuruoka S, Imai M. Effect of protamine on ion selectivity of superficial and juxtamedullary proximal straight tubules. Nephron Clin Pract 1999; 83:154-9. [PMID: 10516495 DOI: 10.1159/000045493] [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: 11/19/2022] Open
Abstract
Protamine is known to inhibit cation selectivity of the paracellular shunt pathway in several leaky nephron segments. Ion permeability of the superficial (SF) proximal straight tubules (PST) is selective to Cl(-), whereas that of the juxtamedullary (JM) PST is selective to Na(+). Protamine was used to estimate the contribution of the paracellular shunt pathway to ion selectivity in these segments. PSTs were isolated from the kidneys of Japanese white rabbit and microperfused in vitro. The ratio of Na(+) to Cl(-) permeability (P(Na)/P(Cl)) was estimated from the diffusion potential (dV(T)) generated by NaCl gradients. When 300 microg/ml protamine was added to the lumen, P(Na)/P(Cl) was decreased from 0.33 to 0.26 in SF-PST and from 1.80 to 1.29 in JM-PST, respectively, as the results of inhibition of cation selectivity. Addition of 30 U/ml heparin to the lumen, which neutralizes protamine, returned the ratios toward the control levels. Protamine exhibited similar effect on P(Na)/P(Cl) in the presence or the absence of ouabain in the bath, indicating that the observed voltage deflections were independent of the transcellular active transport process. Although P(Na)/P(Cl) was different between SF- and JM-PST, protamine inhibits Na(+) permeability in both segments. Preferential Cl(-) permeability in the SF-PST may be intrinsic to the paracellular route of this segment. The mechanism of this anion selectivity remains to be established.
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169
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Imai M, Kaczmarek E, Koziak K, Sévigny J, Goepfert C, Guckelberger O, Csizmadia E, Schulte Am Esch J, Robson SC. Suppression of ATP diphosphohydrolase/CD39 in human vascular endothelial cells. Biochemistry 1999; 38:13473-9. [PMID: 10521254 DOI: 10.1021/bi990543p] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Vascular ATP diphosphohydrolase/CD39 is an endothelial cell membrane protein with both ecto-ATPase and ecto-ADPase activities. Suppression of constitutive CD39 expression may result in elevated concentrations of ATP and ADP at the vascular interface that could predispose to thrombosis and inflammation. To study the effects of suppression of CD39 synthesis, stable 25-base antisense chimeric oligonucleotides targeting sequences at the 5' region of CD39 were designed. Transfection of these stable oligomers into cultured human endothelial cells resulted in dramatic decreases in levels of CD39 mRNA transcripts. Following transfection with antisense oligonucleotides, total ADPase activity fell from 26.0 +/- 3.1 in control cultures to 9.5 +/- 3.4 nmol of P(i) min(-1) (mg of protein)(-1) (p < 0.005); suppression of CD39 protein expression was also observed by Western blotting. Decreases in ATP diphosphohydrolase activity were associated with increases in concentrations of extracellular purine nucleotides released following stimulation of endothelial cells. Rates of initial hydrolysis of extracellular ATP released from purinergic agonist-stimulated endothelial cells decreased from 17.9 +/- 5.0 to 4.8 +/- 0.5 pmol min(-1) per 10(6) cells (p < 0.005) in antisense transfected cells. Therefore, CD39 regulates extracellular ATP concentrations and may be an important modulator of purinergic receptor activity in vascular endothelial cells.
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Yamazaki M, Kimura K, Watanabe S, Komiyama O, Mishiku Y, Yamamoto K, Sugaya N, Hashimoto Y, Hagiwara N, Maezawa T, Imai M. [Use of a rapid detection assay for influenza virus, on nasal aspirate specimens]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 1999; 73:1064-8. [PMID: 10565123 DOI: 10.11150/kansenshogakuzasshi1970.73.1064] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We investigated the usefulness of a rapid antigen detection kit using optical immunoassay for influenza virus (FLU OIA, BioStar, USA). Nasal aspirates were taken from 92 influenza suspected outpatients between March to April of 1999. Compared with virus isolation and PCR, the sensitivity of FLU OIA was 88.5% and 81.6%, and the specificity was 65.2% and 72.2%. All isolated viruses were influenza type B virus. It was difficult to differentiate the weak-positive and negative cases, leading to the rather low specificity, although the assay procedure was easy and quick. FLU OIA may be a useful rapid diagnosis kit for influenza in pediatric outpatient clinics and wards, because it can detect both influenza type A and type B viruses.
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Shimizu H, Kawakami C, Watanabe S, Hirai Y, Imai M. [Evaluation of rapid detection kit using neuraminidase activity of influenza virus]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 1999; 73:1084-5. [PMID: 10565128 DOI: 10.11150/kansenshogakuzasshi1970.73.1084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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172
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Ishibashi K, Imai M. Identification of four new members of the rat prolactin/growth hormone gene family. Biochem Biophys Res Commun 1999; 262:575-8. [PMID: 10471365 DOI: 10.1006/bbrc.1999.1260] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The rodent prolactin (PRL)/growth hormone (GH) gene family currently consists of at least 14 distinct genes that are expressed mainly in pituitary, uterus, and/or placenta. We report here the identification of novel four members from rat with significant homology to PRL. The encoding proteins are not homologs of other known members of this hormone family. The four new cDNAs were assigned to PRL family based on sequence homology and were referred to as PRL-like protein-I (PLP-I), PLP-J, PLP-K, and PLP-L, following the current naming order of rodent PLP family, where PLP-H is the most recent gene. They encode amino acids with 211-228 amino acids, and 34-38% identity with PRL. All have one or two N-linked glycosylation sites. Among the examined rat tissues by Northern blot analysis, only PLP-I was expressed in testis. Our results indicate that the rodent PRL/GH gene family is large with at least 18 distinct genes.
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Ishikura S, Ogino T, Ono M, Arai T, Sugito M, Shimizu W, Kawashima M, Imai M, Ito Y, Ikeda H. Preliminary results of pelvic autonomic nerve-preserving surgery combined with intraoperative and postoperative radiation therapy for patients with low rectal cancer. Jpn J Clin Oncol 1999; 29:429-33. [PMID: 10563196 DOI: 10.1093/jjco/29.9.429] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND In Japan, lateral lymphadenectomy was widely performed for patients with stage II-III rectal tumors because it was thought to contribute to good local control, but the pelvic autonomic nerves were thus sacrificed. Although autonomic nerve-sparing surgery with lateral lymph node dissection has been tried from around 1987, the type of nerve sparing varied and the indications were not established. To examine the possibility of expanding the indications for total pelvic autonomic nerve preservation for patients with low rectal cancer, we conducted a pilot study. METHODS Between 1993 and 1997, a total of 50 patients with low rectal cancer underwent pelvic autonomic nerve preservation with lateral lymphadenectomy of both sides and intraoperative radiation therapy followed by postoperative radiation therapy. RESULTS The median follow-up period for surviving patients was 41 months. The 3-year local control rates for all patients, with stage I-II and stage III tumors were 88% (95% confidence interval, 78-97%), 97% (90-100%) and 73% (52-94%), respectively. The site of local recurrences was not near or within the preserved plexus. CONCLUSIONS The preliminary results showed good local control rate for patients with stage I-II tumors. For patients with stage III tumors, the local control rate was unsatisfactory, but nerve sparing was not the cause of local recurrence. Further investigation of function-preserving surgery without decreasing curability is needed.
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Ishihara S, Nohara R, Makita S, Imai M, Kubo S, Hashimoto T. Immune function and psychological factors in patients with coronary heart disease (I). JAPANESE CIRCULATION JOURNAL 1999; 63:704-9. [PMID: 10496486 DOI: 10.1253/jcj.63.704] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
As part of studies on the effects, especially the preventive effects, of exercise and psychological factors on cardiovascular diseases, the association between psychological tendencies and immune response was evaluated in patients with coronary heart disease who were receiving exercise therapy. The Pearson's product-moment correlation coefficients between natural killer (NK) cell activity and various psychological scales were obtained. For the Moudsley Personality Inventory, NK cell activity had a significant positive correlation with the extraversion scale and a significant negative correlation with the neuroticism scale. NK cell activity also had a significant positive correlation with the playful humor scale and a significantly negative correlation with the Self-rating Depression Scale. The positive correlation of NK cell activity with the extraversion scale and the humor scale and its negative correlation with the neuroticism scale suggest an association between a positive-feeling tendency and high NK cell activity. The negative correlations of NK activity with the depression scale and neuroticism scale indicate that decreased or excessive expression of feelings inhibits NK cell activity. Thus, high NK activity appears to be associated with optimal expression of feelings.
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175
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Hamano S, Tanaka M, Imai M, Nara T, Maekawa K. [Topography and number of cortical tubers in tuberous sclerosis: comparison between patients with and without West syndrome]. NO TO HATTATSU = BRAIN AND DEVELOPMENT 1999; 31:402-7. [PMID: 10487064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
To reveal the role of cortical tubers in the pathophysiology of West syndrome associated with tuberous sclerosis, we studied their numbers and topography, focusing on the differences between patients with infantile spasms and without infantile spasms. We reviewed the clinical date on the seizure types, seizure evolution and developmental status of 13 patients: 8 patients with infantile spasms (the West syndrome group) and 5 patients without infantile spasms (the non-West syndrome group). The number, size and location of the cortical tubers were evaluated on 5 mm-thick T2-weighted MR images. The average number of cortical tubers of the West syndrome group was 11.4 per patient, being larger than that of the non-West syndrome group (7.8). The West syndrome group included two patients with only one tuber. The average number of the cortical tubers in the occipital lobes of the West syndrome group was 2.4, which was larger than that of the non-West syndrome group (0.8). From these results, a large number of cortical tubers, which suggest involvement of larger cerebral cortical regions, increase the possibility of the West syndrome in patients with tuberous sclerosis. On the other hand, some patients with only one or few cortical tubers developed West syndrome, which may suggest the presence of a region critical on the development of West syndrome. Our results also suggest that lesions in the occipital lobes might be more significant than those in other lobes. However, the results of this study are diverse, to some extent, which may have resulted from variable epileptogenicity of the cortical tubers. It is necessary to conduct further study, including a greater number of patients, to reveal topographic pathophysiology in West syndrome.
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Enjyoji K, Sévigny J, Lin Y, Frenette PS, Christie PD, Esch JS, Imai M, Edelberg JM, Rayburn H, Lech M, Beeler DL, Csizmadia E, Wagner DD, Robson SC, Rosenberg RD. Targeted disruption of cd39/ATP diphosphohydrolase results in disordered hemostasis and thromboregulation. Nat Med 1999; 5:1010-7. [PMID: 10470077 DOI: 10.1038/12447] [Citation(s) in RCA: 430] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
CD39, or vascular adenosine triphosphate diphosphohydrolase, has been considered an important inhibitor of platelet activation. Unexpectedly, cd39-deficient mice had prolonged bleeding times with minimally perturbed coagulation parameters. Platelet interactions with injured mesenteric vasculature were considerably reduced in vivo and purified mutant platelets failed to aggregate to standard agonists in vitro. This platelet hypofunction was reversible and associated with purinergic type P2Y1 receptor desensitization. In keeping with deficient vascular protective mechanisms, fibrin deposition was found at multiple organ sites in cd39-deficient mice and in transplanted cardiac grafts. Our data indicate a dual role for adenosine triphosphate diphosphohydrolase in modulating hemostasis and thrombotic reactions.
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Ichikawa S, Ohya H, Kihara M, Sankary TM, Kihara M, Imai M, Kondo M. [The survey of HIV infection among clients of foreign female prostitutes in Tokyo Metropolitan]. [NIHON KOSHU EISEI ZASSHI] JAPANESE JOURNAL OF PUBLIC HEALTH 1999; 46:638-43. [PMID: 10496032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
OBJECTIVES It is important to elucidate the risks to foreign female prostitutes of HIV infection from their clients. We determined the prevalence of HIV among clients of foreign female prostitutes using anonymous testing of condom semen samples. METHODS A total of 250 client condom semen samples were collected with client age and nationality by 15 Latin American and 37 Thai female prostitutes in Tokyo from March to May 1995. We screened by ELISA (GENELAVIA MIXT, Pasteur Sanofi Diagnostics) for antibody to HIV 1 and 2, and then confirmed by Western Blot (LAV Blot 1, LAV Blot 2, Sanofi Diagnostics Pasteur) and distinguished by Immuno Blot PEPTI-LAV 1, 2, (Sanofi Diagnostics Pasteur). RESULTS The nationality of customers was reported as Japanese (74.8%), Iranian (7.6%), Pakistan (5.6%), Indian (2.8%), Taiwanese (2.0%), and Chinese (1.2%) with other nationalities less than 1.0%. Estimated age categories of the clients were < 20 (1.2%), 20-29 (41.2%), 30-39 (36.4%), 40-49 (12.4%), > or = 50 (6.4%) and undetermined (2.4%). Of the 250 samples collected, only 219 were sufficient for testing. Two samples (0.90%, 95% CI = 0.4-2.2%) were HIV 1 positive, both from Japanese clients (1.2% of Japanese clients, 95% CI = 0.5-2.9%). These data suggested that the prevalence of HIV in clients of female prostitutes was relatively high, and can be considered a risk group in Japan. The sentinel surveillance by anonymous of client condom semen samples is a very useful method to quantify HIV prevalence in this risk group.
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Tsuruoka S, Sugimoto KI, Ueda K, Suzuki M, Imai M, Fujimura A. Removal of digoxin and doxorubicin by multidrug resistance protein-overexpressed cell culture in hollow fiber. Kidney Int 1999; 56:154-63. [PMID: 10411688 DOI: 10.1046/j.1523-1755.1999.00516.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Drug removal by hemoperfusion is not effective because of its lower capacity and nonspecificity. We invented a new hybrid type of hemodialysis system. METHODS An immortalized proximal tubular cell line (PCTL) overexpressing human multidrug resistance protein-1 (MDR-1) was cultured either on polus filter membranes or on hollow fiber modules. The modules were incubated in an incubator conditioned with 95% O2/5% CO2 that was kept at 37 degrees C. At 10 days on culture, the drug-transporting capacity of these systems was examined. RESULTS MDR was successfully expressed in the PCTL as evaluated by Western blot. Basolateral to apical transport of 3H-digoxin, a substrate of MDR, was examined by using the cells cultured on a microporous membrane. PCTL-MDR showed a 10-fold increase in MDR protein and a 12-fold increase of 3H-digoxin transport through a cell layer on a microporous membrane. The increase of the transport was abolished by the addition of 5 microM verapamil, an inhibitor of MDR, to the apical side. When digoxin or doxorubicin was infused in the capillary side of the hollow fiber modules after 10 days on culture, the largest portion of the drugs was transported to the pericapillary side (P < 0.001). This transport was also abolished by an addition of verapamil to the pericapillary side. Transport of para-aminohippurate was not different between two cells, and inulin was not transported in this system. CONCLUSION The hybrid hollow fiber system can selectively remove a significant amount of drugs that have an affinity to MDR from the medium, and perfuse them to the capillary side in vitro.
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Imai M, Nakaya K, Kato T. Elasticity effects on domain coarsening of the lamellar-gyroid transition observed in a nonionic surfactant system. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1999; 60:734-9. [PMID: 11969815 DOI: 10.1103/physreve.60.734] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/1998] [Revised: 02/03/1999] [Indexed: 04/18/2023]
Abstract
The coarsening process of the gyroid phase of a nonionic surfactant system is investigated by time resolved small angle neutron scattering (SANS) and small angle neutron Laue diffraction techniques. The time evolution of SANS patterns shows anomalous coarsening of the gyroid domains. The observed Laue spot from a gyroid domain becomes elongated along the radial direction with the elapse of time and at a certain time the elongated spot is split into two spots. The results can be interpreted as follows. During the coarsening process, mismatch of the lattice orientation at the domain boundary brings strong stress to the gyroid domain, resulting in the distortion of the domain. The stored stress in the domain finally brings splitting of the gyroid domain. The elastic and fragile nature of the gyroid domains composed of the "soft matter" is responsible for the anomalous coarsening.
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Hayashi T, Watanabe S, Kondo M, Saito T, Imai M. [Evaluation of a new screening assay kit for the combined detection of HIV p24 antigen and antibody--comparison of the performance of the new kit and HIV antibody assay kits]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 1999; 73:681-8. [PMID: 10481404 DOI: 10.11150/kansenshogakuzasshi1970.73.681] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
DUO is an automated HIV infection screening test kit based on the combined detection of p24 Ag and anti-HIV-1 and anti-HIV-2 IgG in human sera or plasma using the ELFA technique (Enzyme-Linked Fluorescent Assay). The performance of DUO was compared with that of HIV-1/HIV-2 3rd generation EIA plus and particle agglutination (PA) test. A total of 141 seropositive sera, 3 seroconversion panels, 300 seronegative sera and 387 potentially cross-reactive serum samples were tested. One hundred and forty one seropositive sera in Japan and Cameroon were all positive with DUO. Three seroconversion panels (panel Q, Z, AE) were tested to evaluate sensitivity. In Panel Q, infecution was detected seven days earlier with DUO than with the 3rd generation EIA plus and PA. In Panel AE, infection was detected four days earlier with DUO than with the single antibody assays. Three hundred seronegative sera from Kanagawa prefectural public health centers were all negative with DUO as well as PA test. Three hundred and eighty seven potentially cross-reacting samples were tested to challenge the specificity of the assay. These included samples from pregnant women and hepatitis patients. In four of the 204 samples from pregnant women, false-positive results were observed with DUO. In three of the 183 samples from hepatitis patients, false-positive results were also obtained with DUO. All samples of 7 DUO positive results were negative with western blot test. Five of them were negative with RT-PCR and 2 of them were not tested because there were not enough samples. Thirty cross-reacting (false-positive) samples by PA test from blood donors were tested by DUO, and all of these were negative by DUO.
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Hoshino S, Imai M, Kobayashi T, Uchida N, Katada T. The eukaryotic polypeptide chain releasing factor (eRF3/GSPT) carrying the translation termination signal to the 3'-Poly(A) tail of mRNA. Direct association of erf3/GSPT with polyadenylate-binding protein. J Biol Chem 1999; 274:16677-80. [PMID: 10358005 DOI: 10.1074/jbc.274.24.16677] [Citation(s) in RCA: 209] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The mammalian GTP-binding protein GSPT, whose carboxyl-terminal sequence is homologous to the eukaryotic elongation factor EF1alpha, binds to the polypeptide chain releasing factor eRF1 to function as eRF3 in the translation termination. The amino-terminal domain of GSPT was, however, not required for the binding. Search for other GSPT-binding proteins in yeast two-hybrid screening system resulted in the identification of a cDNA encoding polyadenylate-binding protein (PABP), whose amino terminus is associating with the poly(A) tail of mRNAs presumably for their stabilization. The interaction appeared to be mediated through the carboxyl-terminal domain of PABP and the amino-terminal region of GSPT. Interestingly, multimerization of PABP with poly(A), which is ascribed to the action of its carboxyl-terminal domain, was completely inhibited by the interaction with the amino-terminal domain of GSPT. These results indicate that GSPT/eRF3 may play important roles not only in the termination of protein synthesis but also in the regulation of mRNA stability. Thus, the present study is the first report showing that GSPT/eRF3 carries the translation termination signal to 3'-poly(A) tail ubiquitously present in eukaryotic mRNAs.
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Isoyama K, Imai M, Yamada K. Rebound cerebrospinal fluid pleocytosis with elevated cytokine levels during recombinant human granulocyte colony-stimulating factor therapy for purulent meningitis. Pediatr Int 1999; 41:304-6. [PMID: 10365583 DOI: 10.1046/j.1442-200x.1999.01057.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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184
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Tanaka M, Hamano S, Imai M, Nara T. [Lissencephaly type I: electroencephalographic findings and neuroradiological classification]. NO TO HATTATSU = BRAIN AND DEVELOPMENT 1999; 31:269-75. [PMID: 10355268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Lissencephaly type I is a diffuse type of migration disorder that contains agyria and/or pachygyria on the brain surface. We experienced 5 cases of this disease and evaluated their electroencephalographic findings and seizure types based on the neuroradiological classification of lissencephaly. Ages at seizure onset ranged from 2 months to 4 months (mean 3.2 months). The patients with complete agyria had generalized tonic seizures, and those with pachygyria partial seizures or tonic spasms. The characteristic findings of complete agyria in electroencephalogram were high-voltage alfa activity. The amount of high-voltage slow waves increased with the ratio of pachygyria on the brain surface. The appearance of multifocal spikes and sharp waves suggested irregular arrangement of pachygyria on the brain surface.
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Hayashi Y, Imai M, Yanagiguchi K, Viloria IL, Ikeda T. Hydroxyapatite applied as direct pulp capping medicine substitutes for osteodentin. J Endod 1999; 25:225-9. [PMID: 10425944 DOI: 10.1016/s0099-2399(99)80147-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Tissue changes in rat incisors after direct pulp capping with hydroxyapatite (OH-AP) have been investigated using light and electron microscopy. Immediately after direct pulp capping, necrotic cells and cell debris were scattered only in the superficial zone of an exposed site. At day 1, both neutrophils having many vacuoles and macrophages phagocytizing numerous OH-AP granules appeared in the lower part of the OH-AP layer. At day 3, the cells surrounding the basal part of the OH-AP layer had large nuclei and well-developed rough-surfaced endoplasmic reticulum. At day 5, the newly formed mineralized tissue consisting of needle-like crystals was observed directly adjacent to the deepest zone of the OH-AP layer. However, fibroblast-like cells phagocytosing applied OH-AP granules were seen even at this period. These findings suggest that the applied OH-AP could directly substitute for osteodentin.
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186
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Hirakawa H, Iijima H, Gohdo T, Imai M, Tsukahara S. Progression of defects in the central 10-degree visual field of patients with retinitis pigmentosa and choroideremia. Am J Ophthalmol 1999; 127:436-42. [PMID: 10218696 DOI: 10.1016/s0002-9394(98)00408-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PURPOSE To determine the progression of defects in the central 10-degree visual field in patients with retinitis pigmentosa and choroideremia by means of univariate linear regression with respect to the mean deviation. METHODS In a retrospective study, results of automated static perimetry in the central 10-degree visual field were reviewed for patients with retinitis pigmentosa and choroideremia. Univariate linear regression of mean deviation was undertaken for each eye that had field data from at least five tests in addition to the prior static perimetric experience during a period of 3.5 years or more. Data from 30 eyes of 16 patients fulfilled eligibility requirements; the mean number of fields was 5.8 (range, five to 10) and the mean follow-up period was 64 months (range, 42 to 97 months). Eyes were classified as progressive if the regression coefficient was negative and significantly different from zero, with a P value of less than .05. RESULTS Among 14 patients in whom both eyes were eligible for univariate linear regression analysis, a statistically significant progression was demonstrated in both eyes in four patients, only in one eye in five patients, and in neither eye in five patients. One of two patients, in whom only one eye was eligible for the study, showed significant progression in the eye. Overall, 14 (47%) of 30 eyes showed statistically significant progression with respect to the mean deviation. No eye showed significant improvement. CONCLUSIONS Automated static perimetry of the central 10-degree visual field measured approximately once or twice a year demonstrated the progressive nature of the disease with the use of univariate linear regression of mean deviation in 47% of eyes with retinitis pigmentosa and choroideremia during the follow-up period of 3.5 years or more. These results may be useful in understanding the clinical course of the diseases and counseling patients.
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187
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Iijima H, Iida T, Murayama K, Imai M, Gohdo T. Plasminogen activator inhibitor 1 in central serous chorioretinopathy. Am J Ophthalmol 1999; 127:477-8. [PMID: 10218712 DOI: 10.1016/s0002-9394(98)00378-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To describe the plasma level of plasminogen activator inhibitor 1, the major antifibrinolytic agent, in eyes with central serous chorioretinopathy, in which choroidal thrombosis is suspected as the underlying condition based on the findings of choroidal hyperpermeability in indocyanine green angiograms. METHODS Plasminogen activator inhibitor 1 concentrations in the plasma of 17 patients with central serous chorioretinopathy were measured by enzyme-linked immunosorbent assay and compared with those in 12 age-matched normal volunteers. RESULTS The plasma levels of plasminogen activator inhibitor 1 in patients with central serous chorioretinopathy (range, 25 to 439 ng/ml; median, 87 ng/ml) were significantly increased compared with those in normal volunteers (range, 7 to 84 ng/ml; median, 36 ng/ml) (P = .0013, Mann-Whitney U test). CONCLUSION Increased plasminogen activator inhibitor 1 concentrations in patients with central serous chorioretinopathy support the hypothesis that the choroidal hyperpermeability disclosed by indocyanine green angiography is caused from impaired fibrinolysis and the resulting thrombotic occlusion in the choroidal veins.
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188
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Suzuki M, Sato J, Kutsuwada K, Ooki G, Imai M. Cloning of a stretch-inhibitable nonselective cation channel. J Biol Chem 1999; 274:6330-5. [PMID: 10037722 DOI: 10.1074/jbc.274.10.6330] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A homologue of the capsaicin receptor-nonselective cation channel was cloned from the rat kidney to investigate a mechanosensitive channel. We found this channel to be inactivated by membrane stretch and have designated it stretch-inactivated channel (SIC). SIC encodes a 563-amino acid protein with putative six transmembrane segments. The cDNA was expressed in mammalian cells, and electophysiological studies were performed. SIC-induced large cation currents were found to be regulated by cell volume, with currents being stimulated by cell shrinkage and inhibited by cell swelling. Single channel analysis showed a conductance of 250 pS with cation permeability (PCl/PNa < 0.1), and the channel possessed some of the characteristics of a stretch-inactivated channel in that it was permeable to calcium, sensitive to membrane stretch, and blocked by Gd3+. Therefore, we cloned one of the mechanosensitive cation channels of mammals, which is considered to regulate Ca2+ influx in response to mechanical stress on the cell membrane.
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Imai M, Tsuruoka S, Yoshitomi K, Taniguchi J, Suzuki M, Muto S. Morphological and functional heterogeneity of the thick ascending limb of Henle's loop. Clin Exp Nephrol 1999. [DOI: 10.1007/s101570050002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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190
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Iijima H, Imai M, Gohdo T, Tsukahara S. Optical coherence tomography of idiopathic polypoidal choroidal vasculopathy. Am J Ophthalmol 1999; 127:301-5. [PMID: 10088740 DOI: 10.1016/s0002-9394(98)00411-5] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE To document and study the cross-sectional structures of polypoidal elements using optical coherence tomography in eyes with idiopathic polypoidal choroidal vasculopathy. METHODS Optical coherence tomography images of two eyes with idiopathic polypoidal choroidal vasculopathy were correlated with slit-lamp biomicroscopic findings, fundus photographs, fluorescein angiograms, and indocyanine green angiograms. RESULTS Cross-sectional optical coherence tomographic images of retinochoroidal structures showed prominent anterior protrusion of the orange subretinal mass corresponding to the polypoidal structure in the indocyanine green angiogram. Hemorrhagic detachment of the retinal pigment epithelium was contiguous with the cone-shaped nodule beneath the retinal pigment epithelium in one eye, and an apparent discontinuity was observed in the highly reflective layer that delineates the polypoidal structure. CONCLUSIONS Some of the polypoidal structures in eyes with idiopathic polypoidal choroidal vasculopathy are anteriorly protruding lesions in the inner choroid that may cause serosanguineous detachment of the retinal pigment epithelium through damage of the overlying Bruch membrane, retinal pigment epithelium, and the adhesion between them. Cross-sectional optical coherence tomographic images may increase understanding of the pathophysiology of idiopathic polypoidal choroidal vasculopathy.
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Schulte am Esch J, Sévigny J, Kaczmarek E, Siegel JB, Imai M, Koziak K, Beaudoin AR, Robson SC. Structural elements and limited proteolysis of CD39 influence ATP diphosphohydrolase activity. Biochemistry 1999; 38:2248-58. [PMID: 10029517 DOI: 10.1021/bi982426k] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
CD39, the mammalian ATP diphosphohydrolase (ATPDase), is thought to contain two transmembrane domains and five "apyrase conserved regions" (ACR) within a large extracellular region. To study the structure of this ectoenzyme, human CD39 was modified by directed mutations within these ACRs or by sequential deletions at both termini. ATPDase activity was well preserved with FLAG tagging, followed by the removal of either of the demonstrated C- or N-transmembrane regions. However, deletions within ACR-1 (aa 54-61) or -4 (aa 212-220), as well as truncation mutants that included ACR-1, -4, or -5 (aa 447-454), resulted in substantive loss of biochemical activity. Intact ACR-1, -4, and -5 within CD39 are therefore required for maintenance of biochemical activity. Native and mutant forms of CD39 lacking TMR were observed to undergo multimerization, associated with the formation of intermolecular disulfide bonds. Limited tryptic cleavage of intact CD39 resulted in two noncovalently membrane-associated fragments (56 and 27 kDa) that substantially augmented ATPDase activity. Glycosylation variation accounted for minor heterogeneity in native and mutant forms of CD39 but did not influence ATPDase function. Enzymatic activity of ATPDase may be influenced by certain posttranslational modifications that are relevant to vascular inflammation.
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192
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Imai M, Takada A, Okazaki K, Kida H. Antigenic and genetic analyses of H5 influenza viruses isolated from ducks in Asia. THE JAPANESE JOURNAL OF VETERINARY RESEARCH 1999; 46:171-7. [PMID: 10414025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The hemagglutinin (HA) of six H5 influenza virus strains isolated from ducks in Japan and China in 1976 to 1996 were analyzed antigenically and genetically. Antigenic analysis using a panel of monoclonal antibodies revealed that the HA of H5 influenza viruses isolated from ducks are antigenically closely related to each other. Phylogenetic analysis indicates that the isolates from ducks in Hokkaido were derived from an ancestor common with the highly pathogenic isolates from chickens and humans in Hong Kong in 1997.
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193
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Kutsuwada K, Satoh J, Ohki G, Muto S, Imai M, Arakawa M, Suzuki M. Cloning and characterization of 5'-flanking region of mouse non-selective cation channel 1. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1444:92-100. [PMID: 9931454 DOI: 10.1016/s0167-4781(98)00269-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have previously cloned mouse non-selective cation channel 1 (mNSC1) cDNA inducing cation current, from a mouse insulin secreting beta-cell line, MIN6. The current has characteristics of the Ca2+-activated non-selective (CAN) cation channel, and the mRNA is localized in the brain, heart, and lung. To understand the molecular mechanisms of the transcriptional regulation, we have cloned and characterized the 5'-flanking region of mNSC1. By the PCR method, we obtained 987 bp of mouse genomic fragment. The computer program-based analysis revealed that it contained several consensus motifs; insulin responsive element (IRE), AP-2, PEA3, and GC box-like region. But there were neither typical TATA box nor CAAT box. Primer extension analysis and RNase protection assay were performed to identify the transcription start site. Transient transfection analyses using a series of 5'-end deletion and reporter gene constructs with CHO and LA-4 cells demonstrated some relatively active regions. The significantly active border correlated with IRE consensus with CHO cells. This observation may support that CAN current is activated by insulin.
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Akamatsu K, Imai M, Yamasaki Y, Nishikawa M, Takakura Y, Hashida M. Disposition characteristics of glycosylated poly(amino acids) as liver cell-specific drug carrier. J Drug Target 1999; 6:229-39. [PMID: 9888309 DOI: 10.3109/10611869808997897] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Potentials of glycosylated poly(amino acids) as carriers of drugs and/or polynucleotides to the liver were studied in mice in detail. Poly-L-glutamic acid (PLGA) and poly-L-lysine (PLL) were selected as carrier backbones and modified with 2-imino-2-methoxyethyl 1-thiogalactoside or mannoside to obtain galactosylated and mannosylated derivatives. After intravenous injection in mice at a dose of 1 mg/kg, Gal-PLGA and Man-PLGA were selectively taken up by the liver parenchymal cells (PC) and liver nonparenchymal cells (NPC), respectively. Moreover, the uptake of Gal-PLGA and Man-PLGA by the liver were significantly inhibited by the presence of Gal-BSA and Man-BSA, respectively. On the other hand, PLL was targeted to the liver without glycosylation. However, Gal-PLL and Man-PLL showed higher accumulation in the liver than unmodified PLL. Although Gal-PLL and Man-PLL showed different distribution between PC and NPC from that of PLL, the effect of the modifications was less pronounced than the cases of PLGA derivatives. In addition, these glycosylated poly(amino acids) investigated, regardless of the type of amino acid or the sugar grafted, were rapidly degraded to be eluted in the low molecular weight fractions in a gel filtration chromatography. These results suggest that glycosylated PLGAs can be useful carriers of low molecular drugs to the liver cells through conjugation, while glycosylated PLLs could be targetable carriers to the cells after the reduction of their cationic charge by complex formation with polynucleotides.
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Imai M, Tanaka M, Hamano S, Nara T, Maekawa K. [Childhood multiple sclerosis and allied demyelinative diseases]. NO TO HATTATSU = BRAIN AND DEVELOPMENT 1999; 31:44-7. [PMID: 10025134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
We report five cases of multiple sclerosis (MS) and three cases of allied demyelinative diseases starting during childhood. Three of the MS patients presented with atypical initial symptoms, such as acute encephalitis or myelitis, making an early clinical diagnosis difficult. Ophthalmologic symptoms were noted in four of MS children, and in two with allied demyelinative diseases. Therefore, if a child shows ophthalmologic symptoms (i.e. optic neuritis, ophthalmoplegia), brain magnetic resonance imaging (MRI) should be conducted for the differential diagnosis of MS and other demyelinative diseases. Cerebrospinal fluid analysis is not useful for the initial diagnosis of MS, because pleocytosis and increase of oligoclonal IgG band in cerebrospinal fluid are seen in both MS and other demyelinative disorders. However, neuron specific enolase (NSE) is slightly higher in the latter than in the former. T2-weighted MRI of multiple sclerosis showed multiple high intensity areas in the white matter of the cerebrum and cerebellum, capsula interna, and crus cerebri etc. Most of these lesions were clinically silent, being characteristic of MS. In two MS cases, however, initial MRI revealed no abnormal findings. Thus, the diagnosis of MS can not be made by initial MRI only.
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196
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Yatoh S, Kawakami Y, Imai M, Kozawa T, Segawa T, Suzuki H, Yamashita K, Okuda Y. Effect of a topically applied neutralizing antibody against vascular endothelial growth factor on corneal allograft rejection of rat. Transplantation 1998; 66:1519-24. [PMID: 9869094 DOI: 10.1097/00007890-199812150-00016] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Studies in corneal transplant rejection remain important because acute immunologic rejection continues to be the leading cause of human corneal transplant failure. As the permeability of vessels and the neovascularization induce cells infiltration into the graft, we considered the possibility that vascular endothelial growth factor (VEGF), a potent permeability-increasing factor and angiogenesis-mediating factor, could participate in the immune response. METHODS As the established corneal transplant model for rejection, the corneal transplant between Lewis and Fisher rats has been reported. First, we evaluated VEGF production in the graft by immunohistochemical method in the animal model. Next, we tried to neutralize the effect of VEGF by topical administration of anti-VEGF antibody. We administered anti-VEGF antibody as eye drops for 10 days just after the transplantation of the established animal corneal transplant model. RESULTS VEGF was strongly produced from the infiltrative cells into the graft. Anti-VEGF antibody significantly suppressed the acute rejection compared with saline or rabbit IgG. CONCLUSIONS The inhibition of VEGF by topically applied neutralizing antibody is a new potential therapeutic strategy for the treatment of corneal transplantation.
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Kozawa T, Sone H, Okuda Y, Kawakami Y, Sekine Y, Imai M, Hommura S, Inatomi M, Yaguchi S, Matsuo K, Segawa T, Suzuki H, Yamashita K. [Vascular endothelial growth factor levels in the aqueous and serum in diabetic retinopathy with or without neovascular glaucoma]. NIPPON GANKA GAKKAI ZASSHI 1998; 102:731-8. [PMID: 9852717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We determined the levels of vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) in the aqueous and serum in non-insulin dependent diabetic patients with proliferative retinopathy (n = 12) and neovascular glaucoma (n = 11). The aqueous levels of PEGF/VPF were significantly higher in both groups than in 10 diabetics without such complications. The levels were very high in patients with neovascular glaucoma, suggesting that VEGF/VPF is involved in the pathogenesis and progression of diabetic neovascular glaucoma. The serum levels were not significantly related to the presence or the stage of retinopathy. The findings suggest the possibility of treatment of neovascular glaucoma using anti- VRGF/VFP preparations.
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Iijima H, Gohdo T, Imai M, Tsukahara S. Thrombin-antithrombin III complex in acute retinal vein occlusion. Am J Ophthalmol 1998; 126:677-82. [PMID: 9822231 DOI: 10.1016/s0002-9394(98)00226-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
PURPOSE To determine whether quantitative differences in systemic hypercoagulable state could be identified among patients with retinal vein occlusion at various sites of occlusion. METHODS The value of thrombin-antithrombin III complex was determined in 57 patients with retinal vein occlusion within 1 month after the subjective onset of retinal vein occlusion and in 15 age-matched normal controls. RESULTS Levels of log thrombin-antithrombin III complex were significantly higher in the patients with proximal retinal vein occlusion in which the occlusion site is at the optic disc (mean +/- SD, 0.493 +/- 0.389) than in those with distal retinal vein occlusion in which the occlusion site is away from the optic disc (0.312 +/- 0.150, P = .025) and in the normal controls (0.294 +/- 0.151, P = .020). There was no significant difference between the distal retinal vein occlusion and the normal controls (P = .720). More patients with proximal retinal vein occlusion showed elevated thrombin-antithrombin III complex values more than 3.9 ng/ml than those with distal retinal vein occlusion (8/29 vs 1/28, P = .025). Of nine patients showing an initial value of thrombin-antithrombin III complex of more than 3.9 ng/ml, repeated measurements were obtained in eight patients, who showed reduced value of thrombin-antithrombin III complex in the normal range in several months. CONCLUSIONS A systemic hypercoagulable state, which could be demonstrated with the elevation of thrombin-antithrombin III complex value, may contribute more to the development of retinal vein occlusion with thrombus at or near the trunk of the central retinal vein than those with thrombus at branch veins away from the optic disc in the retina.
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Fujiwara N, Nagamine T, Imai M, Tanaka T, Shibasaki H. Role of the primary auditory cortex in auditory selective attention studied by whole-head neuromagnetometer. BRAIN RESEARCH. COGNITIVE BRAIN RESEARCH 1998; 7:99-109. [PMID: 9774711 DOI: 10.1016/s0926-6410(98)00014-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In order to identify the human cortical areas involved in the auditory attention, neuromagnetic fields were recorded from 12 healthy adults with a 122-channel whole-head magnetometer while the subjects performed the auditory selective attention task. Randomized sequence of 900 Hz (P=0.9) and 950 Hz (P=0.1) tones was presented to each ear with random interstimulus intervals across ears ranging from 300 to 500 ms. Subjects were asked to pay attention to the designated ear (attended ear) and to count the number of the 950 Hz tones presented to the attended ear. Twelve sessions were performed for each subject, among which the attended ear was changed alternately in a counterbalanced order among subjects. In seven out of twelve subjects, averaged neuromagnetic fields in response to frequent tones presented to the attended ear showed attention-related deflection over the bilateral temporal areas starting at around 100 ms after the stimulus presentation. Although the dipole moment for N100m in the attended condition showed significant increase compared to that in the non-attended condition, locations of the two equivalent current dipoles in the auditory cortex were not significantly different from each other. Moreover, a simulation study supported the enhancement of N100m rather than participation of additional dipoles in the auditory selective attention task. These results suggest that the primary auditory cortex plays a main role in the auditory selective attention starting as early as 100 ms after the stimulus presentation.
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Kurihara M, Kumagai K, Noda Y, Watanabe M, Imai M. Prognosis in severe motor and intellectual disabilities syndrome complicated by epilepsy. Brain Dev 1998; 20:519-23. [PMID: 9840672 DOI: 10.1016/s0387-7604(98)00038-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We investigated the prognosis of epilepsy in 54 patients with severe motor and intellectual disabilities syndrome (SMIDS). The prevalence of epilepsy was 75.7% in our institution for SMIDS. We assessed activities of daily living (ADL) of them at the onset of epilepsy and at present, according to the scores in locomotion, language, toileting, dressing and feeding. Among them, patients with uncontrolled epilepsy constituted 40.3%. ADL scores worsened in the uncontrolled group, while they improved in other cases. Early seizure control is very important in SMIDS for improving patients' quality of life.
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