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Takano M, Iwadare J, Ohba H, Takamura H, Masuda Y, Matsuo K, Kanai T, Ieda H, Hattori Y, Kurata S, Koganezawa S, Hamano K, Tsuchiya S. Sclerosing therapy of internal hemorrhoids with a novel sclerosing agent. Comparison with ligation and excision. Int J Colorectal Dis 2006; 21:44-51. [PMID: 15843937 DOI: 10.1007/s00384-005-0771-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/15/2005] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND AIMS Patients with prolapsing internal hemorrhoids were treated with a novel sclerosing agent (OC-108), and the results were compared with surgery of ligation and excision. PATIENTS AND METHODS This study included 20 years or older patients with prolapsing internal hemorrhoids who visited ten medical institutions in Japan from October 2000 to October 2002. Investigation on surgery was also performed. RESULTS Comparing OC-108 and surgery in patients with third- and fourth-degree internal hemorrhoids according to the Goligher's classification, for which surgery has been generally indicated, at 28 days after treatment, the disappearance rate of prolapse was similar between OC-108 and surgery, 94% (75/80 patients) and 99% (84/85 patients), respectively. The 1-year recurrence rate was 16% (12/73 patients) in the OC-108 group, and this value was satisfactory because of its less invasive nature while it was more or less higher compared with 2% (2/81 patients) in the surgery group. The incidences of pain and bleeding were lower in the OC-108 group. CONCLUSIONS OC-108 is a useful alternative treatment for hemorrhoids.
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Nanba H, Ikenaka Y, Yamada Y, Yajima K, Takano M, Takahashi S. Production of thermotolerant N-carbamyl-D-amino acid amidohydrolase by recombinant Escherichia coli. J Biosci Bioeng 2005; 87:149-54. [PMID: 16232442 DOI: 10.1016/s1389-1723(99)89004-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/1998] [Accepted: 10/23/1998] [Indexed: 10/17/2022]
Abstract
A plasmid, pNT4553, was constructed for high level production of N-carbamyl-d-amino acid amidohydrolase (DCase), the thermostability of which has been improved by amino acid substitution. The DCase activity and the stability of the plasmid in the host cells were dependent on the Escherichia coli strains used. E. coli HB101 was the most suitable host strain among the 13 types of E. coli tested. E. coli HB101 exhibited the highest activity, i.e. 6.36 units/ml of culture broth in 2YT medium (1.6% tryptone, 1.0% yeast extract, and 0.5% NaCl, pH 7.0), and the plasmid was stably maintained by cultivation in 5 types of E. coli including HB101. Casamino acids, NZ-amine, peptone, and protein extract (a mixture of hydrolyzates of corn gluten, wheat gluten and soybean), were found to be suitable as natural nitrogen sources for both enzyme activity and growth. When cultivation was carried out in the presence of high concentrations of glycerol (6.5%) as the carbon source, and protein extract (3.0%) as the nitrogen source, in a small volume of the medium (20 ml of medium in a 500-ml shaking flask), in which the aeration level was estimated to be high, growth and activity reached OD550=63.8 (17.1 mg of dry cell weight/ml of culture broth) and 22.9 units/ml of culture broth, respectively. The economical hyperproduction of DCase using only inexpensive constituents for the medium was achieved.
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Takano M, Kita T, Kikuchi Y, Yaegashi N, Kuzuya K, Tsuda H, Suzuki M, Kigawa J, Takeuchi S, Sugiyama T. Clinical characteristics of clear cell adenocarcinoma of the ovary - Japan Clear Cell Carcinoma Study Group-. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.5123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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104
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Kudoh K, Kikuchi Y, Kita T, Takano M, Saito K, Fujii K, Sasaki N. The effect of single weekly paclitaxel in heavily pretreated ovarian cancer patients and its antiangiogenic effects. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.5115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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105
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Taogoshi T, Nomura A, Murakami T, Nagai J, Takano M. Transport of prostaglandin E1 across the blood-brain barrier in rats. J Pharm Pharmacol 2005; 57:61-6. [PMID: 15638994 DOI: 10.1211/0022357055173] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
The transport of prostaglandin E(1) (PGE(1)) across the blood-brain barrier (BBB) was characterized using an in-situ rat brain perfusion technique. The uptake of [(3)H]PGE(1) was not affected by shortchain monocarboxylic acids (butyric acid and valeric acid). On the other hand, uptake of [(3)H]PGE(1) was significantly inhibited by medium-chain monocarboxylic acids such as hexanoic acid, enanthic acid and octanoic acid. These medium-chain monocarboxylic acids showed a more potent inhibitory effect on [(3)H]PGE(1) uptake with increasing number of carbon atoms. In contrast, there was no decrease in [(3)H]PGE(1) transport by any dicarboxylic acids with 5-8 carbon atoms. Valproic acid decreased [(3)H]PGE(1) uptake, whereas p-aminohippuric acid, a substrate for the organic anion transporter family, did not inhibit [(3)H]PGE(1) transport. Bromocresol green, an inhibitor of prostaglandin transporter (PGT), strongly decreased [(3)H]PGE(1) transport across the BBB. In addition, digoxin and taurocholate, substrates for organic anion transporting polypeptide subtype 2 (Oatp2), significantly inhibited [(3)H]PGE(1) uptake. RT-PCR analysis revealed that PGT mRNA and Oatp2 mRNA are expressed in a capillary-rich fraction from rat brain. Thus, it is suggested that PGE(1) transport across the BBB is mediated by some specific transport systems, possibly by the members of the Oatp family.
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Shen KM, Ronning F, Lu DH, Baumberger F, Ingle NJC, Lee WS, Meevasana W, Kohsaka Y, Azuma M, Takano M, Takagi H, Shen ZX. Nodal quasiparticles and antinodal charge ordering in Ca2-xNaxCuO2Cl2. Science 2005; 307:901-4. [PMID: 15705845 DOI: 10.1126/science.1103627] [Citation(s) in RCA: 298] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Understanding the role of competing states in the cuprates is essential for developing a theory for high-temperature superconductivity. We report angle-resolved photoemission spectroscopy experiments which probe the 4a0 x 4a0 charge-ordered state discovered by scanning tunneling microscopy in the lightly doped cuprate superconductor Ca2-xNaxCuO2Cl2. Our measurements reveal a marked dichotomy between the real- and momentum-space probes, for which charge ordering is emphasized in the tunneling measurements and photoemission is most sensitive to excitations near the node of the d-wave superconducting gap. These results emphasize the importance of momentum anisotropy in determining the complex electronic properties of the cuprates and places strong constraints on theoretical models of the charge-ordered state.
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Takano M, Kakizawa T, Yama M, Takasaki Y, Akimoto Y. Clinical evaluation of postoperative sability of 2.0 mm locking plate/screw system for saggital splitting ramus osteotomy. Int J Oral Maxillofac Surg 2005. [DOI: 10.1016/s0901-5027(05)81276-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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108
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Shen KM, Ronning F, Lu DH, Lee WS, Ingle NJC, Meevasana W, Baumberger F, Damascelli A, Armitage NP, Miller LL, Kohsaka Y, Azuma M, Takano M, Takagi H, Shen ZX. Missing quasiparticles and the chemical potential puzzle in the doping evolution of the cuprate superconductors. PHYSICAL REVIEW LETTERS 2004; 93:267002. [PMID: 15698008 DOI: 10.1103/physrevlett.93.267002] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2004] [Indexed: 05/24/2023]
Abstract
The evolution of Ca2-xNaxCuO2Cl2 from Mott insulator to superconductor was studied using angle-resolved photoemission spectroscopy. By measuring both the excitations near the Fermi energy as well as nonbonding states, we tracked the doping dependence of the electronic structure and the chemical potential with unprecedented precision. Our work reveals failures in the standard weakly interacting quasiparticle scenario, including the broad line shapes of the insulator and the apparently paradoxical shift of the chemical potential within the Mott gap. To resolve this, we develop a model where the quasiparticle is vanishingly small at half filling and grows upon doping, allowing us to unify properties such as the dispersion and Fermi wave vector with the chemical potential.
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Ishikawa H, Takano M, Matsumoto N, Sawada H, Ide C, Mimura O, Dezawa M. Effect of GDNF gene transfer into axotomized retinal ganglion cells using in vivo electroporation with a contact lens-type electrode. Gene Ther 2004; 12:289-98. [PMID: 15616607 DOI: 10.1038/sj.gt.3302277] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We developed an in vivo electroporation method to introduce foreign genes into retinal ganglion cells (RGCs). After the intravitreous injection of the plasmid gene (20 mug), five electric pulses (6 V/cm, 100 ms duration) were each delivered twice with 5 min interval to the rat eye using a contact lens-type electrode (cathodal) attached to the cornea and a needle electrode (anodal) inserted to the middle of the forehead. The efficiency of the genetic introduction into RGCs and tissue damage to the eyeball was evaluated using a green fluorescent protein (GFP) gene, TUNEL and histological observation. DiI retrograde labeling revealed that 24.4 +/- 4.7% of all RGCs were electrointroduced with the GFP gene. TUNEL and histological analysis showed a few tissue damages in the cornea, lens and retina. To confirm whether this method can actually rescue damaged RGCs, glial cell line-derived neurotrophic factor (GDNF) was electrointroduced into RGCs after optic nerve transection. After the electrointroduction, a significant increase in the number of surviving RGCs was observed 2 and 4 weeks after the optic nerve transection, and the decrease of caspase 3 and 9 was detected by RT-PCR. These results suggest that this method may be useful for the delivery of genes into RGCs with simplicity and minimal tissue damage.
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110
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Khodel VA, Clark JW, Takano M, Zverev MV. Phase transitions in nucleonic matter and neutron-star cooling. PHYSICAL REVIEW LETTERS 2004; 93:151101. [PMID: 15524862 DOI: 10.1103/physrevlett.93.151101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2004] [Indexed: 05/24/2023]
Abstract
A new scenario for neutron-star cooling is suggested by the correspondence between pion condensation, induced by critical spin-isospin fluctuations, and the metal-insulator phase transition in a 2D electron gas. Above the threshold density for pion condensation, the neutron single-particle spectrum acquires an insulating gap that quenches neutron contributions to neutrino production. In the liquid phase just below the transition, the fluctuations play dual roles by (i) creating a multisheeted neutron Fermi surface that extends to low momenta and activates the normally forbidden direct Urca cooling mechanism, and (ii) amplifying the nodeless P-wave neutron superfluid gap while suppressing S-wave pairing. Lighter stars without a pion-condensed core undergo slow cooling, whereas enhanced cooling occurs in heavier stars via direct Urca emission from a thin shell of the interior.
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Kohsaka Y, Iwaya K, Satow S, Hanaguri T, Azuma M, Takano M, Takagi H. Imaging nanoscale electronic inhomogeneity in the lightly doped Mott insulator Ca(2-x)NaxCuO2Cl2. PHYSICAL REVIEW LETTERS 2004; 93:097004. [PMID: 15447131 DOI: 10.1103/physrevlett.93.097004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2003] [Indexed: 05/24/2023]
Abstract
The spatial variation of electronic states was imaged in the lightly doped Mott insulator Ca(2-x)NaxCuO2Cl2 using scanning tunneling microscopy or spectroscopy. We observed nanoscale domains with a high local density of states within an insulating background. The observed domains have a characteristic length scale of 2 nm (approximately 4-5a, a: lattice constant) with preferred orientations along the tetragonal [100] direction. We argue that such spatially inhomogeneous electronic states are inherent to slightly doped Mott insulators and play an important role for the insulator to metal transition.
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112
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Hanaguri T, Lupien C, Kohsaka Y, Lee DH, Azuma M, Takano M, Takagi H, Davis JC. A ‘checkerboard’ electronic crystal state in lightly hole-doped Ca2-xNaxCuO2Cl2. Nature 2004; 430:1001-5. [PMID: 15329714 DOI: 10.1038/nature02861] [Citation(s) in RCA: 587] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2004] [Accepted: 07/13/2004] [Indexed: 11/09/2022]
Abstract
The phase diagram of hole-doped copper oxides shows four different electronic phases existing at zero temperature. Familiar among these are the Mott insulator, high-transition-temperature superconductor and metallic phases. A fourth phase, of unknown identity, occurs at light doping along the zero-temperature bound of the 'pseudogap' regime. This regime is rich in peculiar electronic phenomena, prompting numerous proposals that it contains some form of hidden electronic order. Here we present low-temperature electronic structure imaging studies of a lightly hole-doped copper oxide: Ca2-xNaxCuO2Cl2. Tunnelling spectroscopy (at energies |E| > 100 meV) reveals electron extraction probabilities greatly exceeding those for injection, as anticipated for a doped Mott insulator. However, for |E| < 100 meV, the spectrum exhibits a V-shaped energy gap centred on E = 0. States within this gap undergo intense spatial modulations, with the spatial correlations of a four CuO2-unit-cell square 'checkerboard', independent of energy. Intricate atomic-scale electronic structure variations also exist within the checkerboard. These data are consistent with an unanticipated crystalline electronic state, possibly the hidden electronic order, existing in the zero-temperature pseudogap regime of Ca2-xNaxCuO2Cl2.
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Ohwada M, Machida S, Fujiwara H, Konno R, Takano M, Kita T, Kikuchi Y, Komiyama S, Mikami M, Suzuki M. Phase II study of combination chemotherapy using irinotecan and nedaplatin for patients with primary advanced or recurrent cervical cancer. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.5088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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114
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Yajima Y, Noma H, Furuya Y, Nomura T, Yamauchi T, Kasahara K, Hatada K, Takano M. Quantification of telomerase activity of regions unstained with iodine solution that surround oral squamous cell carcinoma. Oral Oncol 2004; 40:314-20. [PMID: 14747063 DOI: 10.1016/j.oraloncology.2003.08.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The aim of this study was to analyze the iodine-unstained region expanding around oral squamous cell carcinoma (SCC) by quantification of telomerase activity. The epithelial dysplasia often observed around SCC is considered to cause local recurrence or a second primary cancer. However these areas are hard to distinguish from normal mucosa. To clear the border of the expanding epithelial dysplasia around SCC, we stained with 3% iodine solution, and then decided the surgical margin. We measured quantification of telomerase activity in tumor, in epithelial dysplasia, and also in normal epithelium. Thirty-three primary cases of oral SCC which have iodine-unstained region around lesions were investigated. Fluorescense-based TRAP was applied to obtain quantification of telomerase activity. We obtained the following results: histological examination confirmed that every patient's unstained region consisted of various degrees of epithelial dysplasia. The quantified telomerase activities for squamous cell carcinoma, epithelial dysplasia and normal epithelium were 53.9, 39.6 and 2.7 U/microgP, respectively, and there was a significant difference between carcinoma and normal areas, and between dysplasia and normal epithelium. Therefore, these findings suggest that the areas of epithelial dysplasia unstained by iodine consist of cells that are nearly cancerous and excessively proliferative, and that epithelial dysplasia around SCC should be resected together with the tumor. Vital staining with iodine is useful for identifying epithelial dysplasia around SCC.
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115
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Ohtake H, Shimohata T, Terajima K, Kimura T, Jo R, Kaseda R, Iizuka O, Takano M, Akaiwa Y, Goto H, Kobayashi H, Sugai T, Muratake T, Hosoki T, Shioiri T, Okamoto K, Onodera O, Tanaka K, Someya T, Nakada T, Tsuji S. Adult-onset leukoencephalopathy with vanishing white matter with a missense mutation inEIF2B5. Neurology 2004; 62:1601-3. [PMID: 15136690 DOI: 10.1212/01.wnl.0000123117.11264.0e] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We report of a woman aged 52 years born to consanguineous parents and seeking treatment for progressive dementia and delusion. Neurologic examination revealed dementia and emotional instability, indifference, and confabulation. There was also mild spasticity of the bilateral lower limbs. MRI revealed diffuse white matter hyperintensity on T2-weighted images accompanied by hypointense areas on fluid-attenuated inversion recovery images. A homozygous missense mutation was identified in EIF2B5.
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Honda Y, Kubo K, Anderson S, Araki S, Bane K, Brachmann A, Frisch J, Fukuda M, Hasegawa K, Hayano H, Hendrickson L, Higashi Y, Higo T, Hirano K, Hirose T, Iida K, Imai T, Inoue Y, Karataev P, Kuriki M, Kuroda R, Kuroda S, Luo X, McCormick D, Matsuda M, Muto T, Nakajima K, Naito T, Nelson J, Nomura M, Ohashi A, Omori T, Okugi T, Ross M, Sakai H, Sakai I, Sasao N, Smith S, Suzuki T, Takano M, Taniguchi T, Terunuma N, Turner J, Toge N, Urakawa J, Vogel V, Woodley M, Wolski A, Yamazaki I, Yamazaki Y, Yocky G, Young A, Zimmermann F. Achievement of ultralow emittance beam in the accelerator test facility damping ring. PHYSICAL REVIEW LETTERS 2004; 92:054802. [PMID: 14995314 DOI: 10.1103/physrevlett.92.054802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2003] [Indexed: 05/24/2023]
Abstract
For high luminosity in electron-positron linear colliders, it is essential to generate low vertical emittance beams. We report on the smallest vertical emittance achieved in single-bunch-mode operation of the Accelerator Test Facility, which satisfies the requirement of the x-band linear collider. The emittances were measured with a laser-wire beam-profile monitor installed in the damping ring. The bunch length and the momentum spread of the beam were also recorded under the same conditions. The smallest vertical rms emittance measured at low intensity is 4 pm at a beam energy of 1.3 GeV, which corresponds to the normalized emittance of 1.0x1.0(-8) m. It increases by a factor of 1.5 for a bunch intensity of 10(10) electrons. The measured data agreed to the calculation of intrabeam scattering within much better than a factor of 2.
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Gotoh T, Hayashi N, Takeda S, Itoyama S, Takano M, Kikuchi Y. Synchronous mucinous adenocarcinoma of the endometrium and mucinous cystadenoma of bilateral ovaries presenting during fertility therapy. Int J Gynecol Cancer 2004. [DOI: 10.1136/ijgc-00009577-200401000-00025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
We describe a very rare case of synchronous mucinous tumor of the endometrium and ovaries presenting during ovulation induction. A 31-year-old woman received ovulation induction for 5-year primary infertility. Ultrasonography revealed mucus retention in the uterine cavity and bilateral multicystic ovaries during ovulation induction. Atypical hyperplasia was diagnosed by endometrial curettage. Repeated procedures including ovarian cystectomy, endometrial curettage and in vitro fertilization combined with progestine therapy resulted in no pregnancy but rapid recurrences. She finally underwent simple hysterectomy and bilateral salpingo-oophorectomy. Microscopic examination revealed mucinous cystadenoma in the both ovaries and well differentiated mucinous adenocarcinoma of the endometrium.
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Gotoh T, Hayashi N, Takeda S, Itoyama S, Takano M, Kikuchi Y. Synchronous mucinous adenocarcinoma of the endometrium and mucinous cystadenoma of bilateral ovaries presenting during fertility therapy. Int J Gynecol Cancer 2004; 14:169-71. [PMID: 14764048 DOI: 10.1111/j.1048-891x.2004.014168.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
We describe a very rare case of synchronous mucinous tumor of the endometrium and ovaries presenting during ovulation induction. A 31-year-old woman received ovulation induction for 5-year primary infertility. Ultrasonography revealed mucus retention in the uterine cavity and bilateral multicystic ovaries during ovulation induction. Atypical hyperplasia was diagnosed by endometrial curettage. Repeated procedures including ovarian cystectomy, endometrial curettage and in vitro fertilization combined with progestine therapy resulted in no pregnancy but rapid recurrences. She finally underwent simple hysterectomy and bilateral salpingo-oophorectomy. Microscopic examination revealed mucinous cystadenoma in the both ovaries and well differentiated mucinous adenocarcinoma of the endometrium.
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Akao T, Azuma Y, Usuda M, Nishihata Y, Mizuki J, Hamada N, Hayashi N, Terashima T, Takano M. Charge-ordered state in single-crystalline CaFeO3 thin film studied by x-ray anomalous diffraction. PHYSICAL REVIEW LETTERS 2003; 91:156405. [PMID: 14611484 DOI: 10.1103/physrevlett.91.156405] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2002] [Indexed: 05/24/2023]
Abstract
X-ray anomalous diffraction, together with a band-structure calculation, was employed to obtain a quantitative understanding of the charge-ordering state in a single-crystalline CaFeO3 thin film. The experimental result shows a characteristic energy dispersion of the nearly inhibited reflection at 150 K, implying Fe atoms split into two distinct states. The energy dispersion is in good agreement with the calculated spectrum based on the LDA+U scheme. The calculation also reveals an electronic structure of the system where holes in the oxygen orbital surround one of the distinct Fe atoms, in spite of the total electron number in both Fe atoms remaining unchanged.
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Tanaka M, Kusumi T, Oshitani N, Nishigami T, Iwao Y, Hatada Y, Sugita A, Yao T, Takano M, Iizuka B, Mukai M, Maeda K, Fukuda S, Morita T, Hara M, Saito H, Kudo H. Validity of simple mucosal biopsy criteria combined with endoscopy predicting patients with ulcerative colitis ultimately requiring surgery: a multicenter study. Scand J Gastroenterol 2003; 38:594-8. [PMID: 12825866 DOI: 10.1080/00365520310000564] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Recent mucosal biopsy criteria combined with endoscopy effectively differentiate patients with ulcerative colitis ultimately requiring surgery (UC-S) from those receiving medication alone (UC-M). However, the criteria were inconvenient in practical use because of the need for complicated calculations, and the validity has not been verified in other institutes where the indications for surgery may differ. The aims of this multicenter study were to propose simple criteria in which calculation can be performed by mental arithmetic and to measure their validity. METHODS Based on the above original criteria, we constructed simple criteria in which coefficients and constant were simplified to integral numbers. The criteria consisted of the diagnostic categories, highest-risk, high-risk, unpredictable, low-risk, and lowest-risk of surgery. The validity of these proposed criteria was evaluated in 121 patients with UC-S and 186 with UC-M from 11 institutes. RESULTS The categories of high-risk and low-risk had sensitivities exceeding 86.0% and specificities exceeding 95.2%, and the validities were maintained at high levels in most individual institutes. There was little difference in validity between the proposed and original criteria when testing using the same patients. CONCLUSIONS Despite simplified coefficients and constant, the proposed criteria reliably predicted the eventual clinical outcome of patients with ulcerative colitis and would be helpful in determining the necessity of surgery.
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Igarashi S, Tanaka K, Takano M, Iwai H, Oka K, Yasuhara M, Hirano N, Kawanishi H, Yamada H, Nagata K. 4P-1037 Combination treatment of the microsomal triglyceride transfer protein inhbiitr, T-1026 and bezafibrate lowered plasma lipid levels without liver fat accumulation in hyperlipidemic rats. ATHEROSCLEROSIS SUPP 2003. [DOI: 10.1016/s1567-5688(03)91294-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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123
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Kubo K, Akemoto M, Anderson S, Aoki T, Araki S, Bane KLF, Blum P, Corlett J, Dobashi K, Emma P, Frisch J, Fukuda M, Guo Z, Hasegawa K, Hayano H, Higo T, Higurashi A, Honda Y, Iimura T, Imai T, Jobe K, Kamada S, Karataev P, Kashiwagi S, Kim E, Kobuki T, Kotseroglou T, Kurihara Y, Kuriki M, Kuroda R, Kuroda S, Lee T, Luo X, McCormick DJ, McKee B, Mimashi T, Minty M, Muto T, Naito T, Naumenko G, Nelson J, Nguyen MN, Oide K, Okugi T, Omori T, Oshima T, Pei G, Potylitsyn A, Qin Q, Raubenheimer T, Ross M, Sakai H, Sakai I, Schmidt F, Slaton T, Smith H, Smith S, Smith T, Suzuki T, Takano M, Takeda S, Terunuma N, Toge N, Turner J, Urakawa J, Vogel V, Woodley M, Yocky J, Young A, Zimmermann F. Extremely low vertical-emittance beam in the accelerator test facility at KEK. PHYSICAL REVIEW LETTERS 2002; 88:194801. [PMID: 12005637 DOI: 10.1103/physrevlett.88.194801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2001] [Indexed: 05/23/2023]
Abstract
Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of the Accelerator Test Facility at KEK. We established a tuning method of the damping ring which achieves a small vertical dispersion and small x-y orbit coupling. The vertical emittance was less than 1% of the horizontal emittance. At the zero-intensity limit, the vertical normalized emittance was less than 2.8 x 10(-8) rad m at beam energy 1.3 GeV. At high intensity, strong effects of intrabeam scattering were observed, which had been expected in view of the extremely high particle density due to the small transverse emittance.
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Hata N, Takano M, Kunimi T, Kishida H, Takano T. Lack of antagonism between nicorandil and sulfonylurea in stable angina pectoris. INTERNATIONAL JOURNAL OF CLINICAL PHARMACOLOGY RESEARCH 2002; 21:59-63. [PMID: 11708575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The aim of this study was to clarify whether or not nicorandil (a potassium channel opener) caused adverse reactions in patients with angina pectoris who also had diabetes mellitus treated with sulfonylurea (a potassium channel inhibitor). Nineteen diabetic patients with angina pectoris were enrolled, eight were treated with glibenclamide (group A) and 11 were not (group B). Treadmill exercise testing and frequency of anginal attacks were used to evaluate the severity of angina pectoris. Blood sugar and hemoglobin A1c were measured for evaluation of diabetes mellitus control. Exercise tolerance, frequency of anginal attacks and diabetes mellitus control were not perturbed by treatment in either group. In conclusion, there were no antagonistic reactions from the combination of nicorandil with sulfonylurea in angina pectoris complicated by diabetes mellitus.
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Murakami T, Yumoto R, Nagai J, Takano M. Factors affecting the expression and function of P-glycoprotein in rats: drug treatments and diseased states. DIE PHARMAZIE 2002; 57:102-7. [PMID: 11878184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The expression and function of P-glycoprotein (P-gp), an ATP-dependent efflux pump, were examined in rats pretreated with dexamethasone (DEX), an inducer of P-gp, and in rats with glycerol-induced acute renal failure (ARF) and with CCl4-induced acute hepatic failure (AHF). DEX pretreatment increased the P-gp level and its functional activity in the intestine. In contrast, in ARF and AHF rats, the in vivo P-gp function was systemically suppressed, even though the level of P-gp remained unchanged or rather increased. In Caco-2 cells, the plasma collected from diseased rats exhibited a greater inhibitory effect on P-gp function than did plasma from control rats. A higher-plasma level of corticosterone, an endogenous P-gp substrate/inhibitor, was observed in the disease rats. These findings indicate that the actual in vivo function of P-gp cannot be predicted merely from the expression level of P-gp, and suggest that some endogenous P-gp-related compounds such as corticosterone participate in the regulation of in vivo P-gp function in diseased states.
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Kawakami T, Nasu S, Sasaki T, Kuzushita K, Morimoto S, Endo S, Yamada T, Kawasaki S, Takano M. Pressure-induced transition from a charge-disproportionated antiferromagnetic state to a charge-uniform ferromagnetic state in Sr(2/3)La(1/3)FeO3. PHYSICAL REVIEW LETTERS 2002; 88:037602. [PMID: 11801087 DOI: 10.1103/physrevlett.88.037602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2001] [Indexed: 05/23/2023]
Abstract
The perovskite oxide Sr(2/3)La(1/3)FeO3 has been found to switch its electronic ground state drastically at 23 GPa through measurements of 57Fe Mössbauer spectroscopy and powder x-ray diffraction up to 56 GPa. In the low-pressure region a first-order transition from a charge-uniform paramagnetic metallic phase to a charge-disproportionated (3Fe(11/3+)-->2Fe(3+)+Fe5+) antiferromagnetic insulating phase occurs at 207 K at 0.1 MPa and 165 K at 21 GPa, typically. Above 25 GPa, however, a charge-uniform ferromagnetic (and most probably metallic) phase persists below 300 K. This switching occurs at a lattice volume of V(23 GPa)/V(0)(0.1 MPa) = 0.89.
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Utsuki S, Kurata A, Miyasaka Y, Takano M, Ootaka H, Fujii K. Multiple arteriovenous malformations with hemorrhage. Acta Neurochir (Wien) 2002; 144:97-101. [PMID: 11807652 DOI: 10.1007/s701-002-8279-0] [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: 11/25/2022]
Abstract
BACKGROUND A rare case of a left temporal arteriovenous malformation (AVM) with bleeding 10 days after removal of another hemorrhagic AVM in the frontal lobe is reported. METHOD A 47-year-old man had an attack of headache and vomiting and was admitted to our hospital. On admission, a CT scan showed subcortical hemorrhage in the left frontal lobe. Left carotid angiography revealed four AVMs and a vertebro-basilar angiogram demonstrated a vascular malformation. FINDINGS First, a hemorrhagic AVM was removed with a hematoma. Following the operation, left carotid angiograms continued to show, AVMs, particularly a temporal AVM with increased blood flow, and after 10 days this hemorrhaged. This was surgically resected and the remaining small AVMs were treated by stereotactic radiosurgery. INTERPRETATION The patient had a high risk of hemorrhage. Adding hemodynamic stress to this situation, hemorrhage would have been expected to occur at an early time after the initial intervention for hemorrhagic AVM. Considering the risk of hemorrhage, other AVMs should undergo surgery as soon as possible after resection of hemorrhagic AVM.
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Koide T, Miyauchi H, Okamoto J, Shidara T, Sekine T, Saitoh T, Fujimori A, Fukutani H, Takano M, Takeda Y. Close correlation between the magnetic moments, lattice distortions, and hybridization in LaMnO3 and La(1-x)Sr(x)MnO3+delta: doping-dependent magnetic circular X-ray dichroism study. PHYSICAL REVIEW LETTERS 2001; 87:246404. [PMID: 11736523 DOI: 10.1103/physrevlett.87.246404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Indexed: 05/23/2023]
Abstract
The first observation of a magnetic circular x-ray dichroism (MCXD) at the Mn L2,3 core edges in antiferromagnetic LaMnO3 shows canted spin and orbital ( m(orb)) moments arising from lattice distortions. An L2,3-edge MCXD in ferromagnetic metals and insulators, La1-xSr(x)MnO3+delta, reveals that m(orb) of Mn strongly depends on x in the metallic regime but remains unchanged with the metal-to-insulator transition (x approximately 0.16). An O K-edge MCXD, which shows m(orb) of O caused by 2p-3d hybridization, is much larger in the ferromagnetic metal than insulator phases, sharply contrasting with m(orb) of Mn. Our findings indicate a close magnetism-lattice-hybridization coupling.
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Koizumi M, Yamamoto Y, Ito Y, Takano M, Enami T, Kamata E, Hasegawa R. Comparative study of toxicity of 4-nitrophenol and 2,4-dinitrophenol in newborn and young rats. J Toxicol Sci 2001; 26:299-311. [PMID: 11871126 DOI: 10.2131/jts.26.299] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The toxicities of 4-nitrophenol and 2,4-dinitrophenol in newborn and young rats was examined and the susceptibility of newborn rats was analyzed in terms of presumed unequivocally toxic and no observed adverse effect levels (NOAELs). In the 18-day repeated dose newborn rat study, 4-nitrophenol was orally given from Day 4 to Day 21 after birth but did not induce any toxicity up to 160 mg/kg in the main study, although it induced death in one of six males at 160 mg/kg, and three of six males and one of six females at 230 mg/kg in a prior dose-finding study. In the 28-day repeated dose oral toxicity study starting at 6 weeks of age, 4-nitrophenol caused the death of most males and females at 1,000 mg/kg but was not toxic at 400 mg/kg except for male rat-specific renal toxicity. As unequivocally toxic levels were considered to be 230 mg/kg/day in newborn rats and 600 to 800 mg/kg/day in young rats, and NOAELs were 110 mg/kg/day in newborn rats and 400 mg/kg/day in young rats, the susceptibility of the newborn to 4-nitrophenol appears to be 2.5 to 4 times higher than that of young animals. In the newborn rat study of 2,4-dinitrophenol, animals died at 30 mg/kg in the dose-finding study and significant lowering of body and organ weights was observed at 20 mg/kg in the main study. In the 28-day young rat study, clear toxic signs followed by death occurred at 80 mg/kg but there was no definitive toxicity at 20 mg/kg. As unequivocally toxic levels and NOAELs were considered to be 30 and 10 mg/kg/day in newborn rats and 80 and 20 mg/kg/day in young rats, respectively, the toxicity of 2,4-dinitrophenol in newborns again seems to be 2 to 3 times stronger than in young rats. Abnormalities of external development and reflex ontogeny in the newborn were not observed with either chemical. Based on these results, it can be concluded that the toxic response in newborn rats is at most 4 times higher than that in young rats, at least in the cases of 4-nitrophenol and 2,4-dinitrophenol.
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Dezawa M, Takahashi I, Esaki M, Takano M, Sawada H. Sciatic nerve regeneration in rats induced by transplantation of in vitro differentiated bone-marrow stromal cells. Eur J Neurosci 2001; 14:1771-6. [PMID: 11860471 DOI: 10.1046/j.0953-816x.2001.01814.x] [Citation(s) in RCA: 422] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Bone marrow stromal cells (MSCs) are multipotent stem cells that have the potential to differentiate into bone, cartilage, fat and muscle. We now demonstrate that MSCs can be induced to differentiate into cells with Schwann cell characteristics, capable of eliciting peripheral nervous system regeneration in adult rats. MSCs treated with beta-mercaptoethanol followed by retinoic acid and cultured in the presence of forskolin, basic-FGF, PDGF and heregulin, changed morphologically into cells resembling primary cultured Schwann cells and expressing p75, S-100, GFAP and O4. The MSCs were genetically engineered by transduction with retrovirus encoding green fluorescent protein (GFP), and then differentiated by treatment with factors described above. They were transplanted into the cut ends of sciatic nerves, which then responded with vigorous nerve fibre regeneration within 3 weeks of the operation. Myelination of regenerated fibers by GFP-expressing MSCs was recognized using confocal and immunoelectron microscopy. The results suggest that MSCs are able to differentiate into myelinating cells, capable of supporting nerve fibre re-growth, and they can therefore be applied to induce nerve regeneration.
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Takano M, Kudo K, Goto T, Yamamoto K, Kita T, Kikuchi Y. Analyses by comparative genomic hybridization of genes relating with cisplatin-resistance in ovarian cancer. Hum Cell 2001; 14:267-71. [PMID: 11925927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Cisplatin has played a key-role in the management of ovarian cancer patients. Since the mechanisms of cisplatin-resistance have been reported to be multifactorial, it is quite difficult to predict effectiveness of cisplatin-based chemotherapy. In the present study, we have screened abnormal chromosomal regions in cisplatin-resistant and paclitaxel-resistant human ovarian cancer cell lines using comparative genomic hybridization (CGH). Increased copy number at 6q21-25 and decreased copy number at 7q21-36 and 10q12-15 were observed in the cisplatin-resistant cell line. Increased copy number at 7q11.2-21 was observed in paclitaxel-resistant cell lines. Messenger RNA of MDR1 located on chromosomal region of 7q11.2-21 was overexpressed in the paclitaxel-resistant cell lines and recognized as a potential mechanism of acquired paclitaxel-resistance. In CGH analyses of 28 primary epithelial ovarian cancer patients, gains of 1q21-22 (p = 0.0183) and 13q12-14 (p = 0.0407) were observed in significantly high abundance in the cisplatin-resistant tumor group, compared with the cisplatin-sensitive tumor group. These genetic alterations were suggested to be potential indicators for drug resistance.
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Ishii TM, Takano M, Ohmori H. Determinants of activation kinetics in mammalian hyperpolarization-activated cation channels. J Physiol 2001; 537:93-100. [PMID: 11711564 PMCID: PMC2278938 DOI: 10.1111/j.1469-7793.2001.0093k.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
1. The structural basis for the different activation kinetics of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels was investigated with the whole-cell patch clamp technique by using HCN1, HCN4, chimeric channels and mutants in a mammalian expression system (COS-7). 2. The activation time constant of HCN4 was about 40-fold longer than that of HCN1 when compared at -100 mV. 3. In chimeras between HCN1 and HCN4, the region of the S1 transmembrane domain and the exoplasmic S1-S2 linker markedly affected the activation kinetics. The cytoplasmic region between S6 and the cyclic nucleotide-binding domain (CNBD) also significantly affected the activation kinetics. 4. The S1 domain and S1-S2 linker of HCN1 differ from those of HCN4 at eight amino acid residues, and each single point mutation of them changed the activation kinetics less than 2-fold. However, the effects of those mutations were additive and the substitution of the whole S1 and S1-S2 region of HCN1 by that of HCN4 resulted in a 10- to 20-fold slowing. 5. The results indicate that S1 and S1-S2, and S6-CNBD are the crucial components for the activation gating of HCN channels.
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Dezawa M, Takano M, Negishi H, Mo X, Oshitari T, Sawada H. Gene transfer into retinal ganglion cells by in vivo electroporation: a new approach. Micron 2001; 33:1-6. [PMID: 11473808 DOI: 10.1016/s0968-4328(01)00002-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We developed a new in vivo electroporation method to deliver genes into retinal ganglion cells (RGCs). Efficiency and degree of tissue damage were evaluated using green fluorescent protein (GFP) gene and TUNEL. Soon after the intravitreous injection of the GFP gene, electroporation (five electric pulses of 99 ms duration each and 12V/cm delivered twice 5 min apart) was carried out on the adult rat eyeball with the aid of tweezer-type disc electrodes attached to corneal (cathode) and scleral (anode) surfaces. GFP expression, exhibiting a maximum on day 7, was detectable for up to 21 days. DiI retrograde labeling of RGCs showed that 41.5% of the total ganglion cells in the electroinjected area were GFP-positive. Therefore, this new method may be a useful tool for the delivery of genes into RGCs.
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Imamura H, Matsumoto S, Hayase M, Oda Y, Kikuchi H, Takano M. [A case of Hirayama's disease successfully treated by anterior cervical decompression and fusion]. NO TO SHINKEI = BRAIN AND NERVE 2001; 53:1033-8. [PMID: 11761912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The authors report the case of a 16-year-old boy with Hirayama's disease(juvenile muscular atrophy of unilateral upper extremity). The present history began about 6 months previously, when he noticed slowly progressive weakness with atrophy of the left hand and forearm. Neurological examination on admission revealed diffuse distribution of muscular atrophy including the left hypothenar, thenar, forearm, and triceps muscles. However, EMG studies identified neurogenic changes in both upper extremities. There was no long tract sign of objective sensory impairment. Plain spinal radiograms showed abnormal kyphosis of the cervical vertebrae. Cervical MR images in the neutral position demonstrated focal atrophy of the cervical cord at the C 5-6 vertebral levels. When the neck was flexed, the cervical cord was displaced anteriorly and was compressed over the posterior surface of the C 5-6 vertebral bodies. He was diagnosed to have Hirayama's disease(cervical flexion myelopathy). Via an anterior approach, he underwent a C 5 vertebrectomy followed by fixation of C 4-6 vertebral bodies using iliac bone and plate system. He recovered from surgery without any complications and has been well for the past 6 months with remarkable improvement of muscle strength. Application of cervical collar for 3 to 4 years has been generally advocated for the treatment of Hirayama's disease because progression of signs and symptoms is usually expected to cease within several years. However, some patients were reported not to response to conservative treatment for more than 5 years after their onsets. To these patients surgery seems to be beneficial, because it can give rise to permanent stable fixation with much shorter period of external cervical immobilization compared with cervical collar therapy, in which long-term application is frequently unbearable in many patients. In conclusion, the present case emphasizes the importance of surgical treatment in Hirayama's disease not only to improve neurological deficits but regain better quality of life.
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Kubota T, Horie M, Takano M, Yoshida H, Takenaka K, Watanabe E, Tsuchiya T, Otani H, Sasayama S. Evidence for a single nucleotide polymorphism in the KCNQ1 potassium channel that underlies susceptibility to life-threatening arrhythmias. J Cardiovasc Electrophysiol 2001; 12:1223-9. [PMID: 11761407 DOI: 10.1046/j.1540-8167.2001.01223.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Congenital long QT syndrome (LQTS) is a genetically heterogeneous arrhythmogenic disorder caused by mutations in at least five different genes encoding cardiac ion channels. It was suggested recently that common polymorphisms of LQTS-associated genes might modify arrhythmia susceptibility in potential gene carriers. METHODS AND RESULTS We examined the known LQTS genes in 95 patients with definitive or suspected LQTS. Exon-specific polymerase chain reaction single-strand conformation polymorphism and direct sequence analyses identified six patients who carried only a single nucleotide polymorphism in KCNQ1 that is found in approximately 11% of the Japanese population. This 1727G>A substitution that changes the sense of its coding sequence from glycine to serine at position 643 (G643S) was mostly associated with a milder phenotype, often precipitated by hypokalemia and bradyarrhythmias. When heterologously examined by voltage-clamp experiments, the in vitro cellular phenotype caused by the single nucleotide polymorphism revealed that G643S-KCNQ1 forms functional homomultimeric channels, producing a significantly smaller current than that of the wild-type (WT) channels. Coexpression of WT-KCNQ1 and G643S-KCNQ1 with KCNE1 resulted in approximately 30% reduction in the slow delayed rectifier K+ current I(Ks) without much alteration in the kinetic properties except its deactivation process, suggesting that the G643S substitution had a weaker dominant-negative effect on the heteromultimeric channel complexes. CONCLUSION We demonstrate that a common polymorphism in the KCNQ1 potassium channel could be a molecular basis for mild I(Ks) dysfunction that, in the presence of appropriate precipitating factors, might predispose potential gene carriers to life-threatening arrhythmias in a specific population.
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Takano M, Aoki K. [A case of untreated systemic lupus erythematosus presenting with listerial meningitis]. Rinsho Shinkeigaku 2001; 41:588-91. [PMID: 11968742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
A fourty-year-old woman suffered from meningitis and sepsis of Listeria monocytogenes, after presenting with several early symptoms from systemic lupus erythematosus (SLE). Listeriosis often causes central nervous system infection with relatively high mortality rate. This infection commonly affects patients with predisposing factor, such as immunosuppression. According to the previous reports, all of the previous reports, all of listeriosis with SLE received immunosuppressive therapy. To the best of our knowledge, no case of listeriosis has ever been reported in SLE patients without medication to SLE, although most of the previously reported cases of listeriosis with collagen disease accompanied SLE. We presume that suppression of T cell-mediated immunity, which is characteristic of SLE, plays a role as a predisposing factor in listerial infection.
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Gotoh T, Kikuchi Y, Takano M, Kita T, Ogata S, Aida S. Epithelioid leiomyosarcoma of the uterine cervix. Gynecol Oncol 2001; 82:400-5. [PMID: 11531304 DOI: 10.1006/gyno.2001.6288] [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
BACKGROUND Leiomyosarcomas with an epithelioid appearance arising in the uterine cervix are extremely rare neoplasms. We present a case of triple uterine cancer containing cervical epithelioid leiomyosarcoma. CASE A 72-year-old Japanese woman, gravida 1, para 1, 55 years in menopause, visited her local doctor due to atypical bleeding and the endometrial smear was suspect for malignancy. She was referred to our hospital. Endometrial curettage revealed endometrioid adenocarcinoma, G1, with a fragment of sarcomatous tumor. A total hysterectomy with bilateral salpingo-oophorectomy was performed. The histological findings revealed triple uterine cancer consisting of endometrial adenocarcinoma, cervical epithelioid leiomyosarcoma, and cervical squamous cell carcinoma. CONCLUSION This extremely rare case of triple uterine cancer containing cervical epithelioid leiomyosarcoma is the first report, to the best of our knowledge.
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Nagai J, Tanaka H, Nakanishi N, Murakami T, Takano M. Role of megalin in renal handling of aminoglycosides. Am J Physiol Renal Physiol 2001; 281:F337-44. [PMID: 11457726 DOI: 10.1152/ajprenal.2001.281.2.f337] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The role of megalin in tissue distribution of aminoglycosides was examined in normal rats and maleate-treated rats that shed megalin from the renal brush-border membrane. In normal rats, amikacin administered intravenously accumulated most abundantly in the renal cortex, followed by the renal medulla. No amikacin was detected in other tissues. Tissue distributions of amikacin were well correlated with megalin levels in each tissue. Bolus administration of gentamicin increased urinary excretion of megalin ligands (vitamin D binding protein and calcium), suggesting the competition between gentamicin and these megalin ligands in renal tubules. Ligand blotting showed that binding of (45)Ca(2+) to megalin was inhibited by aminoglycosides. Both megalin levels and amikacin accumulation in renal cortex were decreased by maleate injection. Then, amikacin accumulation recovered proportionate to megalin levels. These findings suggest that megalin is involved in the renal cortical accumulation of aminoglycosides in vivo. In addition, the interaction between aminoglycosides and calcium in the kidney may be due to the competition among these compounds to bind to megalin.
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Takano M, Mizuno K, Okamatsu K, Yokoyama S, Ohba T, Sakai S. Mechanical and structural characteristics of vulnerable plaques: analysis by coronary angioscopy and intravascular ultrasound. J Am Coll Cardiol 2001; 38:99-104. [PMID: 11451303 DOI: 10.1016/s0735-1097(01)01315-8] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES Mechanical and structural characteristics of vulnerable plaques were evaluated using coronary angioscopy and intravascular ultrasound. BACKGROUND Mechanical stress and composition of plaques play an important role in plaque disruption. METHODS Thirty-eight lesions in 38 patients were examined pre-interventionally. The plaques were classified as either yellow or white using coronary angioscopy. Intravascular ultrasound imaging was performed simultaneously with electrocardiographic and intracoronary pressure recordings to calculate distensibility index and stiffness beta. Moreover, the type of remodeling was classified. RESULTS We identified 27 patients with yellow plaques and 11 patients with white plaques. Patients with yellow plaques presented acute coronary syndromes more frequently than stable angina (85% vs. 36%, p < 0.01). The distensibility index in yellow plaques was significantly greater than it was in white plaques (2.7 +/- 0.8 mm Hg(-1) vs. 0.7 +/- 0.8 mm Hg(-1), p < 0.0001), while stiffness beta for white plaques was significantly greater than it was for yellow plaques (34.9 +/- 16.3 vs. 8.7 +/- 2.7, p < 0.0001). Compensatory enlargement occurred more frequently with yellow plaques than with white plaques (56% vs. 9%, p < 0.01), while paradoxical shrinkage occurred more frequently with white plaques than it did with yellow plaques (64% vs. 4%, p < 0.001). CONCLUSIONS Yellow plaques with an increased distensibility and a compensatory enlargement may be mechanically and structurally weak. As a result, mechanical "fatigue," caused by repetitive stretching, may lead to plaque disruption. Plaques with a high distensibility and a compensatory enlargement may be vulnerable.
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Kubo N, Takano M, Nishiguchi M, Kadowaki K. Mitochondrial sequence migrated downstream to a nuclear V-ATPase B gene is transcribed but non-functional. Gene 2001; 271:193-201. [PMID: 11418240 DOI: 10.1016/s0378-1119(01)00537-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A promiscuous nuclear sequence containing a mitochondrial DNA fragment was isolated from rice. Nucleotide sequence analysis reveals that the cDNA clone #21 carries a mitochondrial sequence homologous to the 3' portion of the rps19 gene followed by the 5' portion of the rps3 gene. The mitochondrial sequence is present in an antisense orientation. Sequence comparison of the #21 cDNA with the original mitochondrial sequence shows 99% similarity, suggesting a recent transfer event. Moreover, evidence for a lack of an RNA editing event and retaining of the group II intron sequence strongly suggests that the sequence was transferred from mitochondrion to the nucleus via DNA rather than RNA as an intermediate. The upstream region to the mitochondria-derived sequence shows homology to part of the vacuolar H(+)-ATPase B subunit (V-ATPase B) gene. Isolation of a functional V-ATPase B cDNA and its comparison with the #21 cDNA reveal a number of nucleotide substitutions resulting in many translational stop codons in the #21 cDNA. This indicates that the #21 cDNA sequence is not functional. Analysis of genomic sequences shows the presence of five intron sequences in the #21 cDNA, whereas the functional V-ATPase B gene has 14 introns. Of these, three exons and their internal two introns are homologous to each other, suggesting a duplication event of V-ATPase B genomic DNA. The results of this investigation strongly suggest that the mitochondrial sequence was integrated in an antisense orientation into the pre-existing V-ATPase B pseudogene that can be transcribed and spliced. This represents a case of unsuccessful gene transfer from mitochondrion to the nucleus.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Cell Nucleus/enzymology
- Cell Nucleus/genetics
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Mitochondrial/genetics
- DNA, Plant/chemistry
- DNA, Plant/genetics
- Exons
- Genes, Plant/genetics
- Introns
- Molecular Sequence Data
- Oryza/genetics
- Protein Subunits
- Proton-Translocating ATPases/genetics
- Proton-Translocating ATPases/metabolism
- Pseudogenes
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
- Transcription, Genetic
- Vacuolar Proton-Translocating ATPases
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Huang ZH, Murakami T, Okochi A, Yumoyo R, Nagai J, Takano M. Expression and function of P-glycoprotein in rats with carbon tetrachloride-induced acute hepatic failure. J Pharm Pharmacol 2001; 53:873-81. [PMID: 11428664 DOI: 10.1211/0022357011776036] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Acute hepatic failure was induced experimentally in rats by intraperitoneal injection of 2.5 mL kg(-1) carbon tetrachloride (CCl4), and the effects on the expression and function of P-glycoprotein in the liver, kidney and brain were evaluated. The CCl4 injection significantly increased the indicators of hepatic function (glutamate oxaloacetate transaminase, glutamate pyruvate transaminase), but not of renal function (blood urea nitrogen, glomerular filtration rate). In rats with acute hepatic failure, the hepatic P-glycoprotein concentration increased 1.5-fold and the ATP concentration decreased to approximately 40% that in control rats. In contrast, P-glycoprotein concentrations in the kidney and brain and ATP concentrations in the kidney remained unchanged. The in-vivo P-glycoprotein function in these tissues was suppressed as evaluated by biliary and renal secretory clearances and brain distribution of rhodamine 123, a P-glycoprotein substrate. These findings suggest that factors other than P-glycoprotein concentration are involved in the systemic suppression of P-glycoprotein function in diseased rats. In Caco-2 cells, plasma collected from CCl4-treated rats exhibited a greater inhibitory effect on P-glycoprotein-mediated transport of rhodamine 123 than that from control rats, suggesting the accumulation of an endogenous P-glycoprotein substrate/inhibitor in the plasma of diseased rats. In fact, the plasma concentration of corticosterone, an endogenous P-glycoprotein substrate, increased 2-fold in CCl4-treated rats compared with control rats. It was demonstrated that P-glycoprotein function is systemically suppressed in rats with CCl4-induced acute hepatic failure, not only in the target organ (liver), but also in other organs (kidney and brain), although the P-glycoprotein concentration remained unchanged in the kidney and brain, and increased in the liver. In the systemic suppression of the P-glycoprotein function in the diseased state, the alteration of plasma concentrations or components of endogenous P-glycoprotein-related compounds, such as corticosterone, would likely be involved.
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Takano M, Ohno S. [Orbital myositis]. RYOIKIBETSU SHOKOGUN SHIRIZU 2001:609-11. [PMID: 11212819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Hatada K, Noma H, Katakura A, Yama M, Takano M, Ide Y, Takaki T, Yajima Y, Shibahara T, Kakizawa T, Tonogi M, Yamane G. Clinicostatistical study of ameloblastoma treatment. THE BULLETIN OF TOKYO DENTAL COLLEGE 2001; 42:87-95. [PMID: 11588819 DOI: 10.2209/tdcpublication.42.87] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The purpose of this study was to investigate the treatment of 190 cases of ameloblastoma in our department from 1966 to 1994. The statistical results with regard to age, sex and region agreed with those of other investigators. Thirty-five of 43 (81.4%) cases underwent enucleation in 1960s, but the sixteen of 27 (59.3%) cases underwent partial resection of mandible in 1990s. The defect of mandible was reconstructed with iliac bone grafting since 1968, grafts with a mixture of iliac blocked bone and PCBM (particulate cancellous bone and marrow) have been used since 1975. Grafting of the inferior alveolar nerve with the great auricular nerve to the defect has been performed in our department since 1977. Recently, technique involving pull-through of the inferior alveolar nerve bundle has been used in our department. When the reconstruction method for the mandible and nerve has been established, it becomes possible to operate radically and positively. Recurrence occurred in 17 cases after the primary enucleation. It is thought that the primary treatment of ameloblastoma must be as radical as possible. It appears to be necessary to observe progress and perform follow-up in cases of ameloblastoma for more than ten years, because there was one recurrence at 9 years and 4 months after the first operation. In fact, three quarters of our cases were lost to follow-up. Such losses can problems in confirming recurrence and responding rapidly.
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Ishizaka A, Hasegawa N, Nakamura K, Takagi Y, Takano M, Yamaguchi K, Kubo A. Usefulness of pulmonary vascular leakiness assessment in interstitial pneumonitis. Chest 2001; 119:1455-60. [PMID: 11348953 DOI: 10.1378/chest.119.5.1455] [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: 02/05/2023] Open
Abstract
STUDY OBJECTIVE Pulmonary vascular leakiness of (67)Ga-circulating transferrin in interstitial pneumonitis (IP) was estimated by our previously described method, and its ability to evaluate disease activity was compared with conventional (67)Ga scintigraphy. DESIGN Using 30-min dynamic scanning data after IV injection of (67)Ga citrate, the exponential equilibration coefficient of (67)Ga between the intravascular and pulmonary interstitial compartments was calculated and defined as the leak index (LI). Pulmonary (67)Ga uptake was assessed by gallium index, determined by conventional static images taken 48 h after (67)Ga citrate injection. SETTING Hospitalized patients. PARTICIPANTS The study population consisted of 17 control patients and 20 patients with IP. RESULTS The mean LI in patients with IP was significantly higher than in the control group (p < 0.0001), whereas no significant increase in gallium index was noted between the IP group and the control group. No significant correlation was found between gallium index and LI among all study participants. Mean LI in patients with active IP was significantly higher than in patients with stable IP (p = 0.0024). CONCLUSIONS An increase in pulmonary vascular leakiness was found in patients with IP. LI may be useful to assess the disease activity.
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Teramoto N, Yunoki T, Takano M, Yonemitsu Y, Masaki I, Sueishi K, Brading AF, Ito Y. Dual action of ZD6169, a novel K(+) channel opener, on ATP-sensitive K(+) channels in pig urethral myocytes. Br J Pharmacol 2001; 133:154-64. [PMID: 11325805 PMCID: PMC1572759 DOI: 10.1038/sj.bjp.0704042] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. The effects of ZD6169, a novel K(+) channel opener, on both membrane and unitary currents in pig urethra were investigated using patch-clamp techniques. Its effect was also examined on currents in inside-out patches of COS7 cells expressing carboxy terminus truncated inwardly rectifying K(+) channel (Kir6.2) subunits (Kir6.2C36) which form ATP-sensitive K(+) channels (K(ATP) channels). 2. In current-clamp mode, ZD6169 (< or = 10 microM) induced a concentration-dependent membrane hyperpolarization. Higher concentrations (> or = 30 microM) caused a transient membrane hyperpolarization, followed by a gradual membrane depolarization. On removal of ZD6169, an after hyperpolarization was observed. 3. In conventional voltage-clamp configuration, at -50 mV in symmetrical 140 mM K(+) conditions, ZD6169 (100 microM) caused a transient inward current which gradually decayed. Removal of ZD6169 evoked a much larger amplitude K(+) current with a similar time course. 4. ZD6169 produced an inward glibenclamide-sensitive K(+) current, demonstrating a bell-shaped concentration-response relationship. 5. In cell-attached configuration in symmetrical 140 mM K(+) conditions, ZD6169 (< or = 30 microM) activated an K(ATP) channel which was reversibly suppressed by application of glibenclamide. In contrast, ZD6169 (100 microM) inhibited the activity of the levcromakalim-induced K(ATP) channels. 6. ZD6169 (100 microM) had no significant effect on the channel activity of Kir6.2C36 in inside-out configuration, although cibenzoline greatly suppressed the channel activity. 7. These results demonstrate that ZD6169 possesses a dual effect on the activity of the K(ATP) channel; activating at low concentration and inhibiting at higher concentration.
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Briggs WR, Beck CF, Cashmore AR, Christie JM, Hughes J, Jarillo JA, Kagawa T, Kanegae H, Liscum E, Nagatani A, Okada K, Salomon M, Rüdiger W, Sakai T, Takano M, Wada M, Watson JC. The phototropin family of photoreceptors. THE PLANT CELL 2001; 13:993-7. [PMID: 11424903 PMCID: PMC1464709 DOI: 10.1105/tpc.13.5.993] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
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Hara T, Yoshino N, Takayama N, Minamitani M, Naganawa S, Ohkubo H, Takizawa M, Izumi Y, Kantake M, Suzuki S, Takano M, Kita T, Totani R, Nagai Y, Honda M, Nakasone T. Presence of multiple HIV type 1 subtypes among mothers and children in Japan. AIDS Res Hum Retroviruses 2001; 17:569-75. [PMID: 11350671 DOI: 10.1089/08892220151126706] [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: 11/12/2022] Open
Abstract
We collected blood samples from 70 HIV-1-infected pregnant women and 76 babies born to HIV-1-infected women in Japan, from 1989 to 1999. To analyze the genetic diversity of HIV-1 among mothers and children, we sequenced the C2-V3 regions of HIV-1 gp120. Phylogenetic tree analysis of these regions revealed that multiple HIV-1 subtypes, A, B, D, E, and G, were circulating among mothers and children in Japan. Thus, the genetic heterogeneity of HIV-1 among mothers and children in Japan is steadily increasing, although the number of cases remains small. Perhaps the longest term survivor, an 11-year-old child with a vertical HIV-1 subtype G infection in Japan, is one of our subjects.
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Sasaki Y, Nagai J, Kitahara Y, Takai N, Murakami T, Takano M. Expression of chloride channel, ClC-5, and its role in receptor-mediated endocytosis of albumin in OK cells. Biochem Biophys Res Commun 2001; 282:212-8. [PMID: 11263994 DOI: 10.1006/bbrc.2001.4557] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
By using Western blot and RT-PCR analyses, the expression of ClC-5, a member of the ClC family of voltage-gated chloride channels, and its mRNA was detected in OK cells. The effect of chloride channel inhibitors on receptor-mediated endocytosis of albumin was examined in OK cells and compared to that of vacuolar H(+)-ATPase inhibitors. Accumulation of fluorescein-isothiocyanate (FITC)-albumin, a receptor-mediated endocytosis marker, was inhibited by 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), a chloride channel inhibitor, in a concentration-dependent fashion. In contrast, uptake of FITC-inulin, a fluid-phase endocytosis marker, was not affected by NPPB. Other chloride channel inhibitors, 4,4'-diisothiocyanatostilbene-2-2'-disulfonic acid and diphenylamine-2-carboxylic acid, also inhibited FITC-albumin uptake. NPPB, as well as a vacuolar H(+)-ATPase inhibitor bafilomycin A(1), caused a decrease in the affinity and in the maximal velocity of FITC-albumin uptake. These results suggest that chloride channel, most likely ClC-5, plays an important role in the receptor-mediated endocytosis of albumin in OK cells.
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Takano M, Kanegae H, Shinomura T, Miyao A, Hirochika H, Furuya M. Isolation and characterization of rice phytochrome A mutants. THE PLANT CELL 2001; 13:521-34. [PMID: 11251094 PMCID: PMC135516 DOI: 10.1105/tpc.13.3.521] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2000] [Accepted: 01/23/2001] [Indexed: 05/18/2023]
Abstract
To elucidate phytochrome A (phyA) function in rice, we screened a large population of retrotransposon (Tos17) insertional mutants by polymerase chain reaction and isolated three independent phyA mutant lines. Sequencing of the Tos17 insertion sites confirmed that the Tos17s interrupted exons of PHYA genes in these mutant lines. Moreover, the phyA polypeptides were not immunochemically detectable in these phyA mutants. The seedlings of phyA mutants grown in continuous far-red light showed essentially the same phenotype as dark-grown seedlings, indicating the insensitivity of phyA mutants to far-red light. The etiolated seedlings of phyA mutants also were insensitive to a pulse of far-red light or very low fluence red light. In contrast, phyA mutants were morphologically indistinguishable from wild type under continuous red light. Therefore, rice phyA controls photomorphogenesis in two distinct modes of photoperception--far-red light-dependent high irradiance response and very low fluence response--and such function seems to be unique and restricted to the deetiolation process. Interestingly, continuous far-red light induced the expression of CAB and RBCS genes in rice phyA seedlings, suggesting the existence of a photoreceptor(s) other than phyA that can perceive continuous far-red light in the etiolated seedlings.
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Takano M, Oshida T, Yasojima A, Yamada M, Okagaki C, Sugai M, Suginaka H, Matsushita T. Modification of autolysis by synthetic peptides derived from the presumptive binding domain of Staphylococcus aureus autolysin. Microbiol Immunol 2001; 44:463-72. [PMID: 10941929 DOI: 10.1111/j.1348-0421.2000.tb02521.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The autolytic cell wall hydrolase of Staphylococcus aureus, Atl, contains three highly cationic repeats in the central region of the amino acid sequence, and the repeats are presumed to have the role of binding the enzyme to some components on the cell surface. To explain the possible function of the repeats, we synthesized a number of 10- to 30-mer oligopeptides based on the Atl amino acid sequence (Thr432-Lys610) containing repeat 1, and examined their effects on the autolysis of S. aureus cells. When the peptides were added to a cell suspension of S. aureus under low ionic strength conditions, five peptides, A10, A11, A14, A16 and B9, showed immediate increases in optical density (OD) of the cell suspension accompanied by decreases in viable cell counts. After the immediate increases, the ODs for A10 and A14 changed little in the first 2 hr. In contrast, the ODs for A11 and A16 decreased rapidly. When peptide A10 was added to suspensions of heat-killed whole cells, crude cell walls and a crude peptidoglycan preparation, their ODs were increased approximately 2-fold. In contrast, the OD was not increased when the peptide was added to a suspension of pure peptidoglycan from which anionic polymers had been removed. Light microscopic and transmission electron microscopic study showed that A10 and A14 inhibited autolysis and that A11 and A16 induced autolysis earlier than the control. These results suggest strongly that the peptides adsorb to and precipitate on the anionic cell surface polymers such as teichoic acid and lipoteichoic acid via ionic interaction. The effects of peptides on the autolysis may be the results of the modification of S. aureus autolysin activities. These peptides, especially the 10-mer peptide B9 (PGTKLYTVPW) that represents the C-terminal half of A10 and N-terminal half of A11, may be important segments for Atl to bind to the cell surface.
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