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Naganuma T, Maekawa M, Murayama T, Nomura Y. Effects of S-nitroso-cysteine on proteins that regulate exocytosis in PC12 cells: inhibitory effects on translocation of synaptophysin and ADP-ribosylation of GTP-binding proteins. JAPANESE JOURNAL OF PHARMACOLOGY 2000; 84:391-8. [PMID: 11202610 DOI: 10.1254/jjp.84.391] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
S-Nitroso-cysteine (SNC) inhibits Ca2+-induced noradrenaline (NA) release from PC12 cells. Since SNC stimulated Ca2+ mobilization from intracellular Ca2+ pools and SNC-induced inhibition of NA release was not washed-out, SNC may modify exocytosis-related proteins that overcome Ca2+ mobilization. In the present study, we investigated the effects of SNC on exocytosis-related proteins in PC12 cells. Ionomycin stimulated NA release and increased the immunoreactivity of synaptophysin in the cytosol fraction. A 25-kDa synaptosome-associated protein (SNAP-25), which localizes to plasma membranes and vesicles, increased in the cytosol fraction after stimulation. The increases in these proteins by ionomycin were inhibited in PC12 cells treated with 0.6 mM SNC. Synaptobrevin and synapsin-1 in the cytosol fraction, and syntaxin and 43 kDa growth-associated protein in the membrane fraction were not affected by ionomycin or SNC. Incubation of each protein with SNC did not affect antibody immunoreactivity. [32P]ADP-ribosylation of GTP-binding proteins (Gi/Go) by pertussis toxin, but not Gs by cholera toxin, was inhibited in SNC-treated PC12 cells and by co-addition of SNC to the assay mixture. These findings suggest that 1) SNC inhibits translocation of vesicles containing synaptophysin and SNAP-25, and 2) SNC reacts with cysteine residues in Gi/Go, causing inhibition of ADP-ribosylation by pertussis toxin.
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Li J, Kondo A, Maekawa M, Kanamori M, Kanno T. Hypertriglyceridemia characterized by low-density lipoprotein phenotype and lipoprotein lipase gene mutation. Clin Chem Lab Med 2000; 38:1263-70. [PMID: 11205691 DOI: 10.1515/cclm.2000.199] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A high serum triglyceride (TG) concentration is associated with an increased serum concentration of small, dense low-density lipoprotein (LDL). To further characterize the hypertriglyceridemic condition, we examined sera from 240 subjects for small, dense LDL using non-denaturing polyacrylamide gradient gel electrophoresis. We focused on determining the frequency of the pattern B, which is characterized by a higher proportion of small, dense LDL, among hypertriglyceridemic individuals. The subjects were divided into four groups: a control group (TG < or = 1.65 mmol/l, high-density lipoprotein cholesterol (HDL-C) > or =1.17 mmol/l; n = 71), a high TG group (TG > 1.65 mmol/l, HDL-C > or = 1.17 mmol/l; n = 36), a group with high TG and low HDL-C (TG > 1.65 mmol/l, HDL-C < or = 0.91 mmol/l; n = 106), and a low HDL-C group (TG < or = 1.65 mmol/l, HDL-C < or = 0.91 mmol/l; n = 27). We found that pattern B occurs at a high frequency mainly in individuals with high TG and low HDL-C levels. We also observed an increased percentage of LDL within the 20.0 nm to 25.5 nm particle diameter range in this group. Analysis of the lipoprotein lipase gene in this group showed that some mutations seem to be associated with small, dense LDL, resulting in LDL pattern B.
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Ino I, Wu LP, Munakata M, Kuroda-Sowa T, Maekawa M, Suenaga Y, Sakai R. Bridged silver(I) complexes of the polycyclic aromatic compounds tetraphenylethylene and 1,1,4,4-tetraphenyl-1,3-butadiene. Inorg Chem 2000; 39:5430-6. [PMID: 11154557 DOI: 10.1021/ic000263u] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
For the purpose of investigating the coordination behavior of the sterically congested alkenes and exploring the possibility of cofacial complexation in the polycyclic aromatic system for formation of extended polymeric networks, tetraphenylethylene (tphe) and 1,1,4,4-tetraphenyl-1,3-butadiene (tphb) have been studied with regard to their complexation with a silver(I) ion. The crystal structures of [Ag(tphe)(ClO4)(p-xylene)], [Ag2(tphe)(ClO4)2], [Ag4(tphe)(CF3SO3)4], [Ag2(tphb)(ClO4)2], and [Ag2(tphb)(CF3SO3)2], together with the metal-free ligands tphe and tphb, have been determined by single-crystal X-ray diffraction. The pi-electron-rich cleft in organic components is found to offer a potential site for complexation, which can be utilized to generate an interesting array of organometallic compounds with one- and two-dimensional frameworks.
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Ino I, Zhong JC, Munakata M, Kuroda-Sowa T, Maekawa M, Suenaga Y, Kitamori Y. 2-D interwoven and 3-D 5-fold interpenetrating silver(I) complexes of 1-(isocyanidomethyl)-1H-benzotriazole and 1,3-bis(dicyanomethylidene)indan. Inorg Chem 2000; 39:4273-9. [PMID: 11196922 DOI: 10.1021/ic000459u] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper presents novel and distinctive organosilver polymers with intriguing structure motifs, constructed from iodoacetonitrile (L1), 1-(isocyanidomethyl)-1H-benzotriazole (L2), 1,3-bis(dicyanomethylidene)indan (L3), and silver(I) salts, respectively. Treatment of L1 with AgClO4 generated [Ag(L1)(ClO4)]n (1), whose X-ray determination revealed a 2-D wavy sheet structure with square grids. Reaction of L2 with AgPF6 gave rise to a novel 2-D wavy interwoven network, ([Ag(L2)(PO2F2)0.5])n (2). The complex [Ag2(L3)2]n (3) obtained by reaction of AgClO4 with L3 can be regarded as unprecedented 3-D 5-fold interpenetrating nets with columnar aromatic stacks and indicates semiconductive behavior. The IR, ESR spectroscopic results, conductivities, and structural features of the complexes are discussed, respectively. The present findings may provide insight into the coordination versatility of silver(I) and polynitrile ligands and an inspiration for the self-assembly of novel supramolecular networks with multifunctional ligands. Crystal data: 1, C2H2AgINClO4, orthorhombic, Pca2(1) (No. 29), a = 14.503(1) A, b = 5.104(2) A, c = 10.2019(9) A, Z = 4; 2, C8H6AgN4PF4O, orthorhombic, Pnna (No. 52), a = 12.2705(3) A, b = 21.150(1) A, c = 10.040(1) A, Z = 8; 3, C30H10Ag2N8, triclinic, P1 (No. 2), a = 14.920(2) A, b = 11.896(2) A, c = 7.400(4) A, alpha = 86.55(2) degrees, beta = 80.87(2) degrees, gamma = 74.47(1) degrees, Z = 2.
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Shiomi T, Guilleminault C, Sasanabe R, Oki Y, Hasegawa R, Otake K, Banno K, Usui K, Maekawa M, Kanayama H, Takahashi R, Kobayashi T. Primary pulmonary hypertension with central sleep apnea: sudden death after bilevel positive airway pressure therapy. JAPANESE CIRCULATION JOURNAL 2000; 64:723-6. [PMID: 10981861 DOI: 10.1253/jcj.64.723] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An obese 23-year-old man with sleep-disordered breathing and primary pulmonary hypertension (PPH) had been administered oral beraprost sodium, anticoagulant warfarin, and home oxygen therapy, at another hospital as treatment for the PPH, but he had not experienced any symptomatic improvement. The patient had a body mass index of 32.4kg/m2, and complained of fatigue, shortness of breath on exertion, excessive daytime sleepiness, and snoring. Arterial blood gas analysis showed a PaO2 and a PaCO2 of 70.9 and 31.2mmHg, respectively. A polysomnographic study revealed central sleep apnea with an apnea-hypopnea index (AHI) of 29.7episodes/h. The patient showed improvement of daytime sleepiness after starting nocturnal nasal bilevel positive airway pressure (BiPAP) therapy for the central sleep apnea, but his pulmonary hypertension, measured in the daytime, worsened. The patient died suddenly while walking to the bathroom in the morning 1 month after initiation of BiPAP therapy. It is necessary to consider the possibility of sudden death when nasal BiPAP therapy is given to a PPH patient with central sleep apnea.
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Maekawa M, Shiomi T. [Sleep apnea syndrome (SAS) and ischemic heart disease (IHD)]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 2000; 58:1702-6. [PMID: 10944939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Several epidemiological studies have suggested that sleep-disordered breathing is a risk factor for cardiovascular disease, particularly hypertension, stroke and IHD. The relative risk for IHD among obstructive SAS(OSAS) patients is 1.2 to 6.9 higher compared with the general population. The prevalence of SAS with an apnea-hypopnea index(AHI) of 10 and over was 35 to 40% in IHD, while 23.8% of SAS patients had IHD. These evidence suggests that IHD is an important prognostic factor in SAS patients. Characteristic pathophysiological conditions such as sleep apnea-induced hypoxemia and sympathetic activation may play an important role in the genesis of nocturnal angina pectoris. Most patients with OSAS are obese, and the complication of non-insulin dependent diabetes mellitus is quite a few. Insulin resistance is also attracting great attention as a cause of the cardiovascular complication of SAS.
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82
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Maekawa M, Hara K. [A case of hemophagocytosis syndrome with excessive Fe and ferritin concentration in serum and with a good prognosis]. RINSHO BYORI. THE JAPANESE JOURNAL OF CLINICAL PATHOLOGY 2000; 48:730-3. [PMID: 11064596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Investigation in the present case began with a high serum Fe concentration. The routine method for determining serum Fe concentration in our hospital is direct photoscopic assay. When we assayed serum Fe concentration by a deproteinization method, it showed a higher value. We also measured serum ferritin concentration, and suspected that high ferritin interfered with serum Fe concentration. We checked the dose-dependent effect of ferritin on serum Fe determination. The present case, a 64-year-old female, showed a reduction of Plt count, and an elevation of LDH, CRP and so on, meeting most of the criteria for hemophagocytosis syndrome. Bone marrow smears revealed phagocytosis of blood cells. The present case had been followed for rheumatoid arthritis and medicated with oral iron pills. In her liver and spleen, high amounts of Fe had accumulated, and excessive Fe was being released into the blood by any trigger, such as infection, stress, cytokine activation, and/or HPS.
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Hasegawa R, Shiomi T, Sasanabe R, Otake K, Banno K, Oki Y, Maekawa M, Kobayashi T, Ito A, Taniguchi A, Ozeki K. Sleep apnea syndrome in patients with pulmonary thromboembolism. Psychiatry Clin Neurosci 2000; 54:342-3. [PMID: 11186105 DOI: 10.1046/j.1440-1819.2000.00706.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Seven patients (one man and six women) with a diagnosis of pulmonary thromboembolism (PTE) were examined by polysomnography in order to clarify the relationship between sleep-related breathing disorders and PTE. In the chronic stage of PTE, sleep apnea syndrome (SAS) was recognized in two patients (a man and a woman) among the subjects. Four of the five patients without SAS showed nocturnal hypoxemia. The female predominance was different from ordinary SAS without the disease background of PTE even though PTE is accompanied by hypoxemia and pulmonary hypertension like SAS. A pathophysiological relationship between PTE and SAS was not found in this study.
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Ino I, Wu LP, Munakata M, Maekawa M, Suenaga Y, Kuroda-Sowa T, Kitamori Y. Structural studies of silver(I) coordination polymers with aryl iodide derived ligands. Inorg Chem 2000; 39:2146-51. [PMID: 12526526 DOI: 10.1021/ic991261g] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This paper reports novel silver polymers, built with iodine--silver interactions, with interesting structural motifs. Four silver(I) coordination polymers of the aryl iodide derived ligands, triiodobenzoic acid (HL1), tris(4-iodophenyl)amine (L2), and 5,7-diiodo-8-hydroxyquinoline (HL3), have been synthesized and characterized by X-ray crystallography. Treatment of Ag(CH3COO) with HL1 yielded [Ag(L1)] (1), whose structural analysis revealed 2D layers of ladders connected through weak Ag...I interaction. Reactions of AgClO4 and L2 in benzene and nitrobenzene afforded, respectively, two different products, [Ag(L2)(H2O)]ClO4.C6H6(2) and [Ag(L2)(ClO4)](3). While the structure of 2 could be described as a 2D layer of square and octagons perpendicular to [100], complex 3 is formed by 2D layers of the same topology of 2 (8(2).4), alternating as ABAB. In contrast, complex 4, [Ag2(H2L3)(CF3SO3)3], obtained by reaction of Ag(CF3SO3) and HL3, was found to consist of a 2D layer based on columnar arrays AgH2L3-Ag(triflate). The solid-state FT-IR and 109Ag NMR spectra of theses complexes are discussed on the basis of their crystal structures.
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85
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Bito H, Furuyashiki T, Ishihara H, Shibasaki Y, Ohashi K, Mizuno K, Maekawa M, Ishizaki T, Narumiya S. A critical role for a Rho-associated kinase, p160ROCK, in determining axon outgrowth in mammalian CNS neurons. Neuron 2000; 26:431-41. [PMID: 10839361 DOI: 10.1016/s0896-6273(00)81175-7] [Citation(s) in RCA: 251] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We tested the contribution of the small GTPase Rho and its downstream target p160ROCK during the early stages of axon formation in cultured cerebellar granule neurons. p160ROCK inhibition, presumably by reducing the stability of the cortical actin network, triggered immediate outgrowth of membrane ruffles and filopodia, followed by the generation of initial growth cone-ike membrane domains from which axonal processes arose. Furthermore, a potentiation in both the size and the motility of growth cones was evident, though the overall axon elongation rate remained stable. Conversely, overexpression of dominant active forms of Rho or ROCK was suggested to prevent initiation of axon outgrowth. Taken together, our data indicate a novel role for the Rho/ROCK pathway as a gate critical for the initiation of axon outgrowth and the control of growth cone dynamics.
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86
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Ishizaki T, Uehata M, Tamechika I, Keel J, Nonomura K, Maekawa M, Narumiya S. Pharmacological properties of Y-27632, a specific inhibitor of rho-associated kinases. Mol Pharmacol 2000; 57:976-83. [PMID: 10779382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Y-27632 [(+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl)cyclohexanecarboxamide++ + dihydrochloride] is widely used as a specific inhibitor of the Rho-associated coiled-coil forming protein serine/threonine kinase (ROCK) family of protein kinases. This study examined the inhibition mechanism and profile of actions of Y-27632 and a related compound, Y-30141 [(+)-(R)-trans- 4-(1-aminoethyl)-N-(1H-pyrrolo[2, 3-b]pyridin-4-yl)cyclohexan-ecarboxamide dihydrochloride]. Y-27632 and Y-30141 inhibited the kinase activity of both ROCK-I and ROCK-II in vitro, and this inhibition was reversed by ATP in a competitive manner. This suggests that these compounds inhibit the kinases by binding to the catalytic site. Their affinities for ROCK kinases as determined by K(i) values were at least 20 to 30 times higher than those for two other Rho effector kinases, citron kinase and protein kinase PKN. [(3)H]Y-30141 was taken up by cells in a temperature- and time-dependent and saturable manner, and this uptake was competed with unlabeled Y-27632. No concentrated accumulation was found, suggesting that the uptake is a carrier-mediated facilitated diffusion. Y-27632 abolished stress fibers in Swiss 3T3 cells at 10 microM, but the G(1)-S phase transition of the cell cycle and cytokinesis were little affected at this concentration. Y-30141 was 10 times more potent than Y-27632 in inhibiting the kinase activity and stress fiber formation, and it caused significant delay in the G(1)-S transition and inhibition of cytokinesis at 10 microM.
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Okuma Y, Murayama T, Tha KK, Yamada C, Hosokawa M, Ishikawa A, Watanabe R, Maekawa M, Nomura Y. Learning deficiency and alterations in acetylcholine receptors and protein kinase C in the brain of senescence-accelerated mouse (SAM)-P10. Mech Ageing Dev 2000; 114:191-9. [PMID: 10802123 DOI: 10.1016/s0047-6374(00)00103-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The senescence-accelerated mouse (SAM) is known to be a murine model for accelerated aging. A novel inbred SAMP10 has shown age-related brain atrophy and learning deficiency. In the present study, we investigated the changes in learning ability and in ligand binding with muscarinic acetylcholine (mACh) receptors, alpha adrenoceptors and protein kinase C in SAMP10. In Morris's water maze task, in a control strain of SAMR1 at 9 months, the escape latency and path length decreased with increasing trial days, in contrast, escape latency and path length did not decrease in SAMP10. These results indicate that SAMP10 exhibits learning deficiency. The ligand binding activity of mACh receptors decreased in the hippocampus of SAMP10 and the protein kinase C level in the hippocampus of SAMP10 was lower than that of SAMR1. On the other hand, there was no significant difference between SAMR1 and SAMP10 regarding ligand binding activity of alpha(1) and alpha(2) adrenoceptors. Thus, a reduction of mACh receptors and protein kinase C in the brain seems to underlie dysfunction of learning and memory in SAMP10.
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Maekawa M, Satoh S, Murayama T, Nomura Y. Involvement of Hg2+-sensitive sulfhydryl groups in regulating noradrenaline release induced by S-nitrosocysteine in rat brain slices. Biochem Pharmacol 2000; 59:839-45. [PMID: 10718342 DOI: 10.1016/s0006-2952(99)00397-4] [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: 11/30/2022]
Abstract
Nitric oxide has been shown to regulate neurotransmitter release. Previously, we reported that S-nitrosothiols such as S-nitrosocysteine (SNC) stimulate noradrenaline (NA) release in rat hippocampus in vivo and in vitro. To examine the role of sulfhydryl groups in SNC-induced NA release, the effects of metal ions such as Hg2+ and N-ethylmaleimide (NEM, a sulfhydryl alkylating agent) on [3H]NA release from labeled rat brain slices (hippocampus and cerebral cortex) were studied and compared with the effects of SNC. The addition of 200 microM HgCl2, but not Pb2+, Zn2+, or Cd2+, stimulated [3H]NA release from both types of slices in the presence of extracellular CaCl2. p-Chloromercuribenzoic acid (p-CMBA) also stimulated [3H]NA release. NEM stimulated [3H]NA release from both types of slices in the presence and absence of extracellular CaCl2. The effect of 200 microM NEM was enhanced, but the effect of 200 microM SNC was inhibited by co-addition of 200 microM p-CMBA in the absence of extracellular CaCl2. The concentration-response curve of SNC shifted to the right after co-addition of 200 microM p-CMBA or 100 microM HgCl2, although the effect of 200 microM NEM was additive to the effect of SNC. These findings demonstrate that SNC acts as a sulfhydryl agent on proteins that regulate NA release, and that SNC may share the same sulfhydryl groups with Hg compounds. The effect of T-588 ¿(R)-(-)-(benzo[b]thiophen-5-yl)-2-[2-(N,N-diethylamino)ethoxy]eth anol hydrochloride¿, a novel cognitive enhancer and a stimulator of NA release, was compared with the effects of sulfhydryl reagents.
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89
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Beauchemin KA, Rode LM, Maekawa M, Morgavi DP, Kampen R. Evaluation of a nonstarch polysaccharidase feed enzyme in dairy cow diets. J Dairy Sci 2000; 83:543-53. [PMID: 10750113 DOI: 10.3168/jds.s0022-0302(00)74914-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The objective of this study was to evaluate a commercial feed enzyme product (Natugrain 33-L; BASF Corporation, Ludwigshafen, Germany) used mainly in poultry diets for use in ruminant diets. The product contained mainly beta-glucanase, xylanase, and endocellulase activities. The study was conducted as a double 3 x 3 Latin square design with six lactating dairy cows (84 +/- 12 DIM) to measure intake, chewing activities, total tract digestion, and milk production. An additional three cows fitted with ruminal cannulae were used to measure dietary effects on ruminal fermentation and in sacco digestion characteristics. Cows received a diet consisting of 45% forage containing 0, 1.22, or 3.67 L of enzyme product/tonne of total mixed ration (DM basis). Using a low or high concentration of enzyme supplementation increased feed intake, but total tract digestibility only increased with the low concentration of enzyme. As a result, intake of digestible nutrients was increased to a greater extent for cows fed the low concentration than for cows fed the high concentration. Because the cows used in this experiment were in positive energy balance, increased intake of digestible energy due to enzyme supplementation did not increase milk yield or milk component yield. Further research is necessary to determine the mechanism by which adding a fibrolytic enzyme mixture enhanced intake, but only increased feed digestion when used at a low level.
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90
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Ohashi K, Nagata K, Maekawa M, Ishizaki T, Narumiya S, Mizuno K. Rho-associated kinase ROCK activates LIM-kinase 1 by phosphorylation at threonine 508 within the activation loop. J Biol Chem 2000; 275:3577-82. [PMID: 10652353 DOI: 10.1074/jbc.275.5.3577] [Citation(s) in RCA: 393] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
LIM-kinase 1 (LIMK1) phosphorylates cofilin, an actin-depolymerizing factor, and regulates actin cytoskeletal reorganization. LIMK1 is activated by the small GTPase Rho and its downstream protein kinase ROCK. We now report the site of phosphorylation of LIMK1 by ROCK. In vitro kinase reaction revealed that the active forms of ROCK phosphorylated LIMK1 on the threonine residue and markedly increased its cofilin-phosphorylating activity. A LIMK1 mutant (T508A) with replacement of Thr-508 within the activation loop of the kinase domain by alanine was neither phosphorylated nor activated by ROCK. Replacement of Thr-508 by serine changed the ROCK-catalyzed phosphorylation residue from threonine to serine. A LIMK1 mutant with replacement of Thr-508 by two glutamates increased the kinase activity about 2-fold but was not further activated by ROCK. In addition, wild-type LIMK1, but not its T508A mutant, was activated by co-expression with ROCK in cultured cells. These results suggest that ROCK activates LIMK1 in vitro and in vivo by phosphorylation at Thr-508. Together with the recent finding that PAK1, a downstream effector of Rac, also activates LIMK1 by phosphorylation at Thr-508, these results suggest that activation of LIMK1 is one of the common targets for Rho and Rac to reorganize the actin cytoskeleton.
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91
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Maekawa M, Sugano K. [Genetic diagnosis for cancer--tumorigenesis and genetic alterations]. RINSHO BYORI. THE JAPANESE JOURNAL OF CLINICAL PATHOLOGY 2000; 48:143-8. [PMID: 10804817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
During malignant transformation, cancer cells acquire multiple genetic alterations that override the normal mechanisms controlling cellular proliferation. In brief, cancer is a disease of genetic abnormalities caused by hereditary and/or environmental factors. Genetic diagnosis for cancer can be divided into four categories: 1) pre-symptomatic diagnosis, 2) existence diagnosis, 3) property diagnosis-prognosis diagnosis and 4) genetic test for gene therapy. 1) For hereditary cancer families, pre-symptomatic diagnosis is available. Individuals with multiple cancers can be diagnosed by microsatellite instability(MSI) test using resected cancer tissues and by genotyping of mismatch repair enzymes. If the genotype abnormality is detected, the propositus can obtain early diagnosis and prevention of cancer, and genetic services of their siblings. 2) Using PCR technology, occult tumor cells can be detected from blood and other biological body fluids, as targets of chimeric transcripts and tissue-specific expressions. 3) Molecular properties of cancer cells are investigated for grading malignancy and therapeutic sensitivities. Using the molecular properties, prognosis of the patient can be estimated. 4) Following the genetic test results, the specific and superior gene therapy can be applied individually. Post-therapeutic monitoring is also available only by genetic test. After the genome project, the significance of single nucleotide polymorphisms(SNPs) related with cancer will be established, then tailor-made therapy and/or prevention will be applicable to individuals. The ultimate goal of genetic diagnosis would be the final priority to the phenotypic diagnosis.
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92
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Maekawa M, Ono S, Narita H, Murayama T, Nomura Y. Stimulation of noradrenaline release by T-588, a cognitive enhancer, in PC12 cells. JAPANESE JOURNAL OF PHARMACOLOGY 2000; 82:59-66. [PMID: 10874590 DOI: 10.1254/jjp.82.59] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Previously, we reported that (R)-(-)-1-(benzo[b]thiophen-5-yl)-2-[2-(N,N- diethylamino)ethoxy] ethanol hydrochloride (T-588), a novel putative cognitive enhancer, stimulated noradrenaline (NA) release from rat cerebral cortical slices. In this study, we investigated the effects of T-588 compared to other secretagogues on NA release from PC12 cells. Addition of as little as 10 microM T-588 stimulated [3H]NA release in a dose-dependent and an extracellular Ca(2+)-independent manner from PC12 cells. Ten micromolar ionomycin-, 300 microM adenosine-5'-O-(gamma-thiotriphosphate)- and 10 microM forskolin-induced extracellular Ca(2+)-dependent [3H]-NA release was further enhanced by 30 microM T-588. Cytosolic synaptophysin and 25-kDa synaptosome-associated protein immunoreactivity was increased by addition of T-588 in a dose-dependent manner. Interestingly, increases in synaptic vesicle-related proteins triggered by T-588 had a 4-min lag time and were completely dependent on extracellular CaCl2. These findings suggest that T-588 stimulates NA release from PC12 cells in a Ca(2+)-independent manner. T-588 also induced the translocation of synaptic vesicles in a Ca(2+)-dependent manner.
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Dai J, Bian GQ, Zhou MY, Maekawa M, Munakata M. Dichloro(3,4,5,6-tetramethylthio-1,3-benzodithiazole-2-thione- S5, S6)copper(II). Acta Crystallogr C 1999. [DOI: 10.1107/s0108270199098364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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94
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Maekawa M. [Genetic analysis--detection methods of genetic mutation]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1999; 57 Suppl:656-60. [PMID: 10778214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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95
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Sawabe S, Hara K, Maekawa M. [High creatine kinase MB concentration and activity in patients with rhabdomyosarcoma]. RINSHO BYORI. THE JAPANESE JOURNAL OF CLINICAL PATHOLOGY 1999; 47:1079-82. [PMID: 10590688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
A 14-year-old boy with rhabdomyosarcoma (RMS) of the left palm showed increased concentration and activity of creatine kinase (CK; EC 2.7.3.2) MB in his serum. CK isoenzyme analysis revealed no extra band. Other laboratory data including high lactate dehydrogenase (LD) isoenzyme 2, CK isoenzyme BB and MB, neuron specific enolase (NSE), and clinical findings did not support the diagnosis of myocardial infarction. The high activity and concentration of CK-MB in serum is possibly originated from the tumor. We could follow his time-course and analyze laboratory data of him and other 6 patients with RMS. We concluded that CK-MB, both concentration and activity, was the more sensitive marker of disease states of RMS than NSE and LD to follow up the patients with RMS.
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96
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Maekawa M, Nemoto S, Awaya S, Teramoto A. [Moyamoya disease with intraventricular hemorrhage due to rupture of lateral posterior choroidal artery aneurysm: case report]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 1999; 27:1047-51. [PMID: 10565052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Intracranial aneurysms associated with moyamoya disease are often reviewed. Aneurysms not around the circle of Willis but on the collateral vessels are rare. A 71-year-old woman presented with sudden onset of severe headache and vomiting. CT scan showed an intraventricular hemorrhage from bilateral lateral ventricle to fourth ventricle. Cerebral angiography showed the occlusion of the terminal portion of the bilateral internal carotid artery with moyamoya vessels and three aneurysms at the distal portion of the left lateral posterior choroidal artery. Clinical symptoms improved day by day, but 17 days later, due to rebleeding of the aneurysms the patient fell into coma. The day after rebleeding, endovascular embolization was performed using liquid particle, and the left lateral posterior choroidal artery and the aneurysm were occluded. Brain infarction with massive brain edema of the left cerebral hemisphere resulted in the patient's death. The management of the aneurysms in the basal ganglia and on the collateral vessels associated with moyamoya disease is controversial. We suggest positive intervention during the acute stage for the peripheral artery aneurysms taking endovascular embolization into consideration to prevent rupture or rebleeding.
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97
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Suenaga Y, Kuroda-Sowa T, Maekawa M, Munakata M. A linear-chain silver(I) coordination polymer with tetrakis(isopropylthio)-p-benzoquinone. Acta Crystallogr C 1999. [DOI: 10.1107/s0108270199005624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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98
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Maekawa M, Sugano K, Kashiwabara H, Ushiama M, Fujita S, Yoshimori M, Kakizoe T. DNA methylation analysis using bisulfite treatment and PCR-single-strand conformation polymorphism in colorectal cancer showing microsatellite instability. Biochem Biophys Res Commun 1999; 262:671-6. [PMID: 10471384 DOI: 10.1006/bbrc.1999.1230] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The combination of bisulfite treatment and PCR-single-strand DNA conformation polymorphism (SSCP) analysis is proposed for quantitative methylation assay. We applied this procedure to the methylation analysis of the hMLH1 promoter region in colorectal cancer. An analysis of mixtures of known amounts of methylated and unmethylated DNA revealed a linear relation. Using a calibration curve, proportions of methylated DNA were calculated. The hMLH1 promoter region was highly methylated in about 80% of microsatellite instability (MSI) (+) colorectal cancers, but in none of the MSI(-) colorectal cancers. A significant correlation existed between hypermethylation of the hMLH1 promoter and MSI, as in previous reports. In conclusion, bisulfite-PCR-SSCP (BiPS) analysis could be applied to the rapid identification of methylation status in multiple samples, quantification of methylation differences, and detection of methylation heterogeneity in amplified DNA fragments.
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99
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Maekawa M, Ishizaki T, Boku S, Watanabe N, Fujita A, Iwamatsu A, Obinata T, Ohashi K, Mizuno K, Narumiya S. Signaling from Rho to the actin cytoskeleton through protein kinases ROCK and LIM-kinase. Science 1999; 285:895-8. [PMID: 10436159 DOI: 10.1126/science.285.5429.895] [Citation(s) in RCA: 1210] [Impact Index Per Article: 48.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The actin cytoskeleton undergoes extensive remodeling during cell morphogenesis and motility. The small guanosine triphosphatase Rho regulates such remodeling, but the underlying mechanisms of this regulation remain unclear. Cofilin exhibits actin-depolymerizing activity that is inhibited as a result of its phosphorylation by LIM-kinase. Cofilin was phosphorylated in N1E-115 neuroblastoma cells during lysophosphatidic acid-induced, Rho-mediated neurite retraction. This phosphorylation was sensitive to Y-27632, a specific inhibitor of the Rho-associated kinase ROCK. ROCK, which is a downstream effector of Rho, did not phosphorylate cofilin directly but phosphorylated LIM-kinase, which in turn was activated to phosphorylate cofilin. Overexpression of LIM-kinase in HeLa cells induced the formation of actin stress fibers in a Y-27632-sensitive manner. These results indicate that phosphorylation of LIM-kinase by ROCK and consequently increased phosphorylation of cofilin by LIM-kinase contribute to Rho-induced reorganization of the actin cytoskeleton.
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100
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Maekawa M, Awaya S, Teramoto A. [Cerebral blood flow (CBF) before and after cranioplasty performed during the chronic stage after decompressive craniectomy evaluated by xenon-enhanced computerized tomography (Xe-CT) CBF scanning]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 1999; 27:717-22. [PMID: 10457935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Patients who undergo decompressive craniectomy for the purpose of prevention of cerebral herniation sometimes improve neurologically or increase activity of daily life after cranioplasty during the chronic stage. We studied the effect which cranioplasty at the chronic stage had on intracranial environment by means of xenon-enhanced computerized tomography (Xe-CT) CBF scanning. Eight patients underwent decompressive craniectomy at the acute stage and cranioplasty at the chronic stage was reviewed. Xe-CT CBF scanning was performed before and after cranioplasty. On the slice of the basal ganglia. CBF of the symptomatic hemisphere increased in five patients and CBF of the other hemisphere increased in three patients after cranioplasty. On the slice 20 mm above the basal ganglia, CBF of the symptomatic hemisphere increased in five patients and CBF of the other hemisphere increased in four patients after cranioplasty. Cranioplasty after decompressive craniectomy may increase CBF of not only the symptomatic hemisphere but also the other hemisphere.
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