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Taniguchi Y, Nakamura H, Maeta H, Makihara K, Metsugi H, Ishiguro K, Ohgi S. [A new method of reconstruction for chest wall resection]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 2000; 53:396-401. [PMID: 10808290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Sixteen patients who involved in chest wall disease underwent major chest wall resection between April 1995 and January 1999. The underlying diseases were 6 recurrence of breast cancers, 4 direct invasion by primary lung cancer, 2 metastatic chest wall tumor, one direct invasion by metastatic lung tumor, one direct invasion by metastatic mediastinal tumor, one radio-induced-necrosis of the chest wall, and one chest wall infection. In 9 patients, the thoracic cage reconstruction was performed using double sheets of absorbable mesh (Dexon mesh), cross string sutures and autologous ribs grafts. None of the patients had major respiratory failure and chest wall unstability. No late complications including infections, pains, recurrence and others related to reconstruction materials have been observed.
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77
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Jin ZH, Miyoshi N, Ishiguro K, Umemura S, Kawabata K, Yumita N, Sakata I, Takaoka K, Udagawa T, Nakajima S, Tajiri H, Ueda K, Fukuda M, Kumakiri M. Combination effect of photodynamic and sonodynamic therapy on experimental skin squamous cell carcinoma in C3H/HeN mice. J Dermatol 2000; 27:294-306. [PMID: 10875195 DOI: 10.1111/j.1346-8138.2000.tb02171.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We studied a combination of photodynamic therapy (PDT) and sonodynamic therapy (SDT) for improving tumoricidal effects in a transplantable mouse squamous cell carcinoma (SCC) model. Two sensitizers were utilized: the pheophorbide-a derivative PH-1126, which is a newly developed photosensitizer, and the gallium porphyrin analogue ATX-70, a commonly used sonosensitizer. Mice were injected with either PH-1126 or ATX-70 i.p. at doses of 5 or 10 mg/kg.bw. At 24 (ATX-70) or 36 hr (PH-1126) (time of optimum drug concentration in the tumor) after injection, SCCs underwent laser light irradiation (88 J/cm2 of 575 nm for ATX-70; 44J/cm2 of 650 nm for PH-1126) (PDT), ultrasound irradiation (0.51 W/cm2 at 1.0 MHz for 10 minutes) (SDT), or a combination of the two treatments. The combination of PDT and SDT using either PH-1126 or ATX-70 as a sensitizer resulted in significantly improved inhibition of tumor growth (92-98%) (additive effect) as compared to either single treatment (27-77%). The combination using PH-1126 resulted in 25% of the treated mice being tumor free at 20 days after treatment. Moreover, the median survival period (from irradiation to death) of PDT + SDT-treated mice (> 120 days) was significantly greater than that in single treatment groups (77-95 days). Histological changes revealed that combination therapy could induce tumor necrosis 2-3 times as deep as in either of the single modalities. The combination of PDT and SDT could be very useful for treatment of non-superficial or nodular tumors.
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78
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Ishiguro K, Kojima K, Tsubota M, Seki M, Kurumaya H. [Malignant cardiac lymphoma]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 2000; 53:233-5. [PMID: 10714114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
A 65-year-old male was admitted to the hospital in shock. The transesophageal echocardiography showed cardiac tumor in the right atrium. The tumor was resected under cardiopulmonary bypass. It was diagnosed as malignant lymphoma of B-cell type by histological examination. After operation, his general condition became satisfactory. Then he received chemotherapy. Twenty days after operation, however, a mass appeared in the right side of chin. It was diagnosed as malignant lymphoma of the same cell type as in the heart. We searched his body with CT and Ga-scanning. No other lesions were found. After the chemotherapy (CHOP, 6 cycles), the mass disappeared. No recurrence was been observed for six months.
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Takahashi M, Tomizawa K, Ishiguro K. Distribution of tau protein kinase I/glycogen synthase kinase-3beta, phosphatases 2A and 2B, and phosphorylated tau in the developing rat brain. Brain Res 2000; 857:193-206. [PMID: 10700568 DOI: 10.1016/s0006-8993(99)02424-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
When trying to elucidate the role played by tau protein kinase I/glycogen synthase kinase-3beta (TPKI/GSK-3beta) in tau phosphorylation, it is important to consider the balance that exists between the various kinases and phosphatases that are involved in vivo. We studied developmental changes in the expressions of TPKI/GSK-3beta and phosphatases 2A and 2B in rat brains using immunoblot analysis. The expression of the kinase peaked postnatally at days 8-11 and returned then to low level after 5 weeks. Phosphatase 2A showed a similar pattern, increasing postnatally until day 14 and decreasing thereafter. On the other hand, phosphatase 2B was undetectable at the juvenile stage, but later its presence increased rapidly to peak at 5 weeks after birth, after which it was maintained at high levels throughout the adult stage. Immunohistochemical studies using the PAP method revealed details of the distribution of TPKI/GSK-3beta. At postnatal days 3-21 both gray and white matter were immunoreactive. Later, after 5 weeks, the immunoreactivity became more restricted to the gray matter. The staining of tau phosphorylated at Ser 199, Ser 396, and Ser 413 followed mostly the pattern of the kinase distribution throughout all stages of development. These data, therefore, confirm that TPKI/GSK-3beta is expressed primarily in neurons and especially in neurites until postnatal day 21, whereafter the distribution is concentrated mostly in the cell soma and the proximal neurite region.
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80
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Ishiguro K, Kadomatsu K, Kojima T, Muramatsu H, Tsuzuki S, Nakamura E, Kusugami K, Saito H, Muramatsu T. Syndecan-4 deficiency impairs focal adhesion formation only under restricted conditions. J Biol Chem 2000; 275:5249-52. [PMID: 10681494 DOI: 10.1074/jbc.275.8.5249] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Two domains of fibronectin deliver two different but cooperative signals required for focal adhesion formation. The signal from the cell-binding domain is mediated by integrins, whereas the signal from the heparin-binding domain is recognized by heparan sulfate proteoglycans, of which syndecan-4 has been hypothesized to be involved in focal adhesion formation. We generated mice deficient in syndecan-4 to study its role directly. Even in fibroblasts from syndecan-4-deficient mice, focal adhesions were formed, and actin fibers terminated normally at focal adhesions when they were cultured on coverslips coated with fibronectin or with a mixture of its cell-binding and heparin-binding fragments. However, when the cells were cultured on the cell-binding fragment and the heparin-binding fragment was added to the medium, focal adhesion formation was impaired in the syndecan-4 null fibroblasts as compared with that in wild-type cells. Therefore, syndecan-4 is essential for promoting focal adhesion formation only when the signal of the heparin-binding domain of fibronectin is delivered as a soluble form, most probably from the apical surface. When the signal is delivered as a substratum-bound form, other molecule(s) also participate(s) in the signal reception.
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81
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Hamanaka H, Katoh-Fukui Y, Suzuki K, Kobayashi M, Suzuki R, Motegi Y, Nakahara Y, Takeshita A, Kawai M, Ishiguro K, Yokoyama M, Fujita SC. Altered cholesterol metabolism in human apolipoprotein E4 knock-in mice. Hum Mol Genet 2000; 9:353-61. [PMID: 10655544 DOI: 10.1093/hmg/9.3.353] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Thevarepsilon4 allele of apolipoprotein E (apoE) is associated with an increased risk of developing Alzheimer's disease (AD). To accurately determine the isoform-specific effects of human apoE on brain functions under physiological and pathological situations, we created mice expressing human apoE4 isoform in place of mouse apoE by utilizing the gene-targeting technique on the embryonic stem cells (knock-in). The homozygousvarepsilon4 (4/4) mice correctly expressed human apoE4 in the serum and the brain. The human apoE in the brain was found primarily in the astrocytes as was the mouse apoE in the wild-type (+/+) mice. In the 4/4 mice, the serum cholesterol level was 2.5-fold that of the +/+ littermate controls on a regular diet. This marked elevation was accounted for by an accumulation of very low and low density lipo-proteins. In the brains of the 4/4 mice, however, the amounts of total cholesterol and phospholipids were significantly decreased compared with the +/+ littermates. These findings indicate that cholesterol and lipid metabolism is markedly altered in the 4/4 mice. Our human apoE4 knock-in mice will be useful in clarifying the role of apoE in the etiologies of AD and cardiovascular diseases in relation to cholesterol and lipid metabolism.
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82
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Nakagawa T, Imanaka T, Morita M, Ishiguro K, Yurimoto H, Yamashita A, Kato N, Sakai Y. Peroxisomal membrane protein Pmp47 is essential in the metabolism of middle-chain fatty acid in yeast peroxisomes and Is associated with peroxisome proliferation. J Biol Chem 2000; 275:3455-61. [PMID: 10652339 DOI: 10.1074/jbc.275.5.3455] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pmp47 of the methylotrophic yeast Candida boidinii belongs to a mitochondrial family of solute transporters and is localized in peroxisomal membranes. Its human homolog, Pmp34, is also known. In this study, we characterized the role of Pmp47 in fatty acid metabolism and peroxisome proliferation using the PMP47-deleted strain of C. boidinii (strain pmp47Delta). The wild-type strain grew well on a middle-chain fatty acid, laureate, as the single carbon source, and mild peroxisome proliferation was observed during its growth. The pmp47Delta strain could not grow on laureate but could grow on long-chain fatty acids including palmitate, myristate, and oleate. The levels of laureate oxidation activity in intact cells and in semi-permeabilized cells of strain pmp47Delta were lower than the respective level in the wild-type strain, although the level of laureate oxidation activity in the cell lysate and the level of lauroyl-CoA oxidation in semi-permeabilized cells of strain pmp47Delta were indistinguishable from the respective level in the wild-type strain. When lauroyl-CoA was provided in the cytosol of strain pmp47Delta through expression of Saccharomyces cerevisiae Faa2p (lauroyl-CoA synthetase) in which its peroxisome targeting signal was deleted, the growth of strain pmp47Delta on laureate was recovered to the level of growth of the wild-type strain. Laureate is converted to its CoA form in peroxisomes by the action of lauroyl-CoA synthetase. These results suggested that Pmp47 is involved in the transport of a small molecule (possibly ATP) required in the conversion of laureate to its CoA form in peroxisomes and that the absence of Pmp47 causes impairment of laureate metabolism, which results in the inability of pmp47Delta cells to grow on laureate. In addition, Pmp47 may be involved in peroxisome proliferation, because the pmp47Delta strain contained a reduced number of peroxisomes, as judged from the fluorescence analysis of cells expressing green fluorescent protein tagged with the peroxisome targeting signal 1 (GFP-AKL).
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Abstract
The 35% EtOH extract of aerial parts of Impatiens balsamina L. has been investigated for activity against testosterone 5alpha-reductase. Activity-guided fractionation led to the identification of the bisnaphthquione derivative named impatienol (1), 3-hydroxy-2-¿[3-hydroxy-1,4-dioxo (2-naphthyl)] ethyl¿ naphthalene-1, 4-dione, which exhibited significant testosterone 5alpha-reductase inhibitory activity. This 5alpha-reductase inhibitory compound has been previously synthesized, but this is the first report of its isolation from a natural source.
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84
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Shoji M, Kawarabayashi T, Matsubara E, Ikeda M, Ishiguro K, Harigaya Y, Okamoto K. Distribution of amyloid beta protein precursor in the Alzheimer's disease brain. Psychiatry Clin Neurosci 2000; 54:45-54. [PMID: 15558879 DOI: 10.1046/j.1440-1819.2000.00636.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In order to clarify the distribution and pathological changes of the amyloid beta protein precursor (betaAPP), 10 Alzheimer's disease (AD) brains and seven normal control brains were examined by immunocytochemistry and in situ hybridization histochemistry. All betaAPP isoforms were distributed evenly in neuronal cell bodies and their axons and dendrites. The betaAPP-positive neuronal processes showed mesh-like networks. In AD brains, betaAPP-positive neurons and mesh-like networks were generally decreased in spite of some intensely labeled neurons. All betaAPP isoforms accumulated in neuronal processes, dystrophic neurites and senile plaques. In situ hybridization histochemistry confirmed that all isoforms of betaAPP were expressed in neurons in control brains. In AD brains, the betaAPP mRNA signal was generally decreased besides some intense signal neurons corresponding to immunostaining findings. Few astrocytes expressed betaAPP. Thus, uniform expression and distribution of betaAPP were disturbed in AD brains showing uneven decreases or increases of neuronal betaAPP expression in individual neurons and betaAPP accumulation in neurons, neuronal processes and abnormal structures including dystrophic neurites, senile plaques and neurofibrillary tangles.
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85
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Nakamura H, Taniguchi Y, Makihara K, Metsugi H, Maeta H, Ishiguro K, Ohgi S. [Video-assisted thoracic surgery (VATS) for metastatic lung tumor: comparison with thoracotomy]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 2000; 53:34-8. [PMID: 10639791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Effectiveness and present problems of video-assisted thoracic surgery (VATS) for metastatic lung tumor were investigated by comparing 14 cases (16 operations) of VATS with 16 cases (19 operations) of conventional thoracotomy during the same period. VATS was favorably selected in the solitary metastasis. The cases who had small tumor diameter less than 3 cm and shorter distance from viseral pluera to the tumor surface than tumor diameter were advantageous for only thoracoscopic procedure to do the safe and sure resection. Regarding to the tumor number, we detected another tumor intraoperatively in 2 of 16 cases (12.5%) of VATS and 6 of 19 cases (31.6%) of thoracotomy. Multiple metastases had the tendency to have the differences of the tumor number between preoperation and intraoperation. Prognosis is very good until now, but the recurrence rate was high (64.5%) and one case had the recurrence at the surgical margin. VATS for metastatic tumor is very effective, but it is important not to hesitate to do the mini-thoracotomy and convert to conventional thoracotomy for safe and sure resection.
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86
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Nakamura H, Makihara K, Taniguchi Y, Ishiguro K, Ohgi S. Thoracoscopic surgery for intralobar pulmonary sequestration. Ann Thorac Cardiovasc Surg 1999; 5:405-7. [PMID: 10637393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
A 47-year-old male with intralobar pulmonary sequestration successfully treated by thoracoscopic surgery was reported. Preoperative selective angiography revealed two aberrant arteries originating from the left infraphrenic artery. Under thoracoscopy, adhesive tissues around the sequestered lung were dissected, aberrant arteries were divided and the sequestered lung was resected. We considered that preoperative detailed analysis of the aberrant artery was very important to safely perform thoracoscopic procedures for pulmonary sequestration.
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Yanagisawa M, Planel E, Ishiguro K, Fujita SC. Starvation induces tau hyperphosphorylation in mouse brain: implications for Alzheimer's disease. FEBS Lett 1999; 461:329-33. [PMID: 10567721 DOI: 10.1016/s0014-5793(99)01480-5] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hyperphosphorylated tau is the major component of paired helical filaments in neurofibrillary tangles found in Alzheimer's disease brains, and tau hyperphosphorylation is thought to be a critical event in the pathogenesis of this disease. The objective of this study was to reproduce tau hyperphosphorylation in an animal model by inducing hypoglycemia. Food deprivation of mice for 1 to 3 days progressively enhanced tau hyperphosphorylation in the hippocampus, to a lesser extent in the cerebral cortex, but the effect was least in the cerebellum, in correspondence with the regional selectivity of tauopathy in Alzheimer's disease. This hyperphosphorylation was reversible by refeeding for 1 day. We discuss possible mechanisms of this phenomenon, and propose the starved mouse as a simple model to study in vivo tau phosphorylation and dephosphorylation which are altered in Alzheimer's disease.
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Abstract
A blood pressure monitoring system was developed for studying antagonist effects against platelet activating factor (PAF), a chemical mediator of anaphylactic hypotension. Using this system, we were able to determine the inhibitory effects of a 35% ethanol extract (IB) from the petals of Impatiens balsamina L. against PAF-induced hypotension and the active principal compounds from IB. One mechanism of the antianaphylactic effects of IB was characterized as PAF-antagonist effects.
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Abstract
By bioassay-guided fractionation using mushroom tyrosinase, p-coumaric acid was characterized as the principal tyrosinase inhibitor from the fresh leaves of Panax ginseng (Araliaceae). It inhibited the oxidation of L-tyrosine more strongly than that of L-3, 4-dihydroxyphenylalanine (L-DOPA) by this enzyme. On the basis of this finding, various related phenylpropanoid analogues were also tested in order to gain new insights into their structural criteria.
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90
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Ishiguro K, Ohno H, Arai H, Yamaguchi H, Urakami K, Park JM, Sato K, Kohno H, Imahori K. Phosphorylated tau in human cerebrospinal fluid is a diagnostic marker for Alzheimer's disease. Neurosci Lett 1999; 270:91-4. [PMID: 10462105 DOI: 10.1016/s0304-3940(99)00476-0] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Microtubule-associated protein tau in cerebrospinal fluid (CSF) has been proposed as a diagnostic marker for Alzheimer's disease (AD), but there is overlap between AD patients and non-AD controls. To improve the diagnostic accuracy, we measured phosphorylated tau in CSF, because phosphorylated tau accumulates as pathological paired helical filaments in neurons of the AD brain. Immunoblot showed that CSF contained a 32 kDa N-terminal fragment of tau that was partially phosphorylated on Ser199, Thr231 and Ser235. A sandwich enzyme immunoassay revealed that phosphorylated CSF-tau levels were significantly higher in AD patients than those in non-AD controls. Discrimination between the two groups was clearer in phosphorylated CSF-tau than in total CSF-tau. The data indicate that elevated phosphorylated CSF-tau level is a more specific diagnostic marker for AD.
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91
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Ishiguro K, Kojima T, Taguchi O, Saito H, Muramatsu T, Kadomatsu K. Syndecan-4 expression is associated with follicular atresia in mouse ovary. Histochem Cell Biol 1999; 112:25-33. [PMID: 10461809 DOI: 10.1007/s004180050388] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Ovarian granulosa cells synthesize heparan sulfate proteoglycans (HSPGs), that have anticoagulant properties. Moreover, HSPGs greatly increase in the granulosa cells during follicular atresia. However, the species of ovarian HSPGs have not yet been identified. Syndecan-4 (ryudocan, amphiglycan) is a membrane-spanning HSPG and a member of the syndecan family. Herein, we demonstrate that syndecan-4 is expressed in the granulosa cells of type 4-5b follicles and, most intensely, in those of the atretic follicles in the mouse ovary, as revealed by in situ hybridization. There is no relationship between syndecan-4 expression and age or sexual cycle stage. Compared with syndecan-4 expression, syndecan-1 and -3 are expressed more abundantly in postovulatory follicles and the corpora lutea, but less in the type 4-5b follicles and much less in the atretic follicles. Immunohistochemistry also demonstrates syndecan-4 expression in atretic follicles with apoptosis. The present study has revealed the distinct modes of expression of the syndecan family members, and the association of syndecan-4 expression and apoptosis in ovarian atretic follicles.
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92
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Ishiguro K, Yamamoto R, Oku H. Patulosides A and B, novel xanthone glycosides from cell suspension cultures of Hypericum patulum. JOURNAL OF NATURAL PRODUCTS 1999; 62:906-908. [PMID: 10395517 DOI: 10.1021/np980519x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two new xanthone glycosides, patuloside A (3-beta-D-glucopyranosyloxy-1,5,6-trihydroxy-9H-xanthene-9-one, 1) and patuloside B [3-(2-O-alpha-L-rhamnopyranosyl-beta-D-glucopyranosyl)oxy-1,5, 6-trihydroxy-9H-xanthene-9-one, 2], have been isolated from cell suspension cultures of Hypericum patulum. Their structures were elucidated by spectral techniques.
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93
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Tomidokoro Y, Ishiguro K, Igeta Y, Matsubara E, Kanai M, Shizuka M, Kawarabayashi T, Harigaya Y, Kawakatsu S, Ii K, Ikeda M, St George-Hyslop PH, Hirai S, Okamoto K, Shoji M. Carboxyl-terminal fragments of presenilin-1 are closely related to cytoskeletal abnormalities in Alzheimer's brains. Biochem Biophys Res Commun 1999; 256:512-8. [PMID: 10080929 DOI: 10.1006/bbrc.1998.0119] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To clarify the role of presenilin-1 (PS-1) in the pathology of Alzheimer's disease (AD), we tested four antisera to PS-1. The specific antisera to the N-terminus (HSN-2) and C-terminus (HS-C) of PS-1 detected a 44/40kD holoprotein, a 25kD N-terminal fragment (NTF) and a 16kD C-terminal fragment (CTF) of PS-1 in COS-7 cells. The 25kD NTF and 16kD CTF were observed in human brains, and their amounts were not significantly different between the control and AD brains. The antibody HS-C labeled extensive neurofibrillary tangles, dystrophic neurites and curly fibers in the AD brains. In the paired helical filament (PHF) fraction containing A68 protein from AD brains, a smear pattern of CTFs was revealed. Antisera (HS-L292 and HS-L300) to cleavage sites of PS-1 also revealed immunoreactive neurofibrillary tangles in the AD brain sections and the smear pattern of CTFs of A68 protein fraction. The CTFs of PS-1 accumulate with PHF tau, suggesting a close relationship between PS-1 and cytoskeletal abnormalities in AD brains.
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94
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Ishiguro K, Sartorelli AC. Coinduction of embryonic and adult-type globin mRNAs by sodium butyrate and trichostatin A in two murine interleukin-3-dependent bone marrow-derived cell lines. Blood 1998; 92:4383-93. [PMID: 9834245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Using an RNase protection assay, globin mRNA species expressed in clones derived from Ba/F3 and B6SUtA cells transfected with the erythropoietin receptor (EpoR) and selected with erythropoietin (Epo) were compared with globin mRNA species induced in corresponding parental cells by sodium butyrate (SB) and trichostatin A (TSA). betaMajor/betaminor- and -1/-2-globin mRNAs were the major species, with trace amounts of epsilon-globin mRNA, formed in Epo-stimulated EpoR+ Ba/F3 clones, whereas SB and TSA allowed expression of all species of globin mRNAs, ie, epsilon, betah1, betamajor/betaminor, zeta, and -1/-2, in parental Ba/F3 cells. In contrast, epsilon- and -1/-2-globin mRNAs were the major species present in Epo-stimulated EpoR+ B6SUtA clones, whereas SB and TSA activated epsilon-, betah1-, betaS/betaT-, and -1/-2-globin genes in parental B6SUtA cells; zeta-globin mRNA was not detected in SB- and TSA-treated B6SUtA cells. Because TSA is a specific inhibitor of histone deacetylase, the mimicry of action exhibited by SB and TSA suggests that the effects of SB are mediated through its ability to inhibit histone deacetylase and that histone deacetylase is an integral part of the repression of globin genes in these interleukin-3-dependent cells. Efficient coinduction of embryonic and adult types of globin mRNA in bone marrow cell lines derived from adult mice indicates that adult hematopoietic precursors possess an embryonic nature. These cell lines are useful models to study the mechanism(s) of developmental globin gene switching.
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Saito T, Ishiguro K, Onuki R, Nagai Y, Kishimoto T, Hisanaga S. Okadaic acid-stimulated degradation of p35, an activator of CDK5, by proteasome in cultured neurons. Biochem Biophys Res Commun 1998; 252:775-8. [PMID: 9837783 DOI: 10.1006/bbrc.1998.9739] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Degradation of p35, a neuron-specific activator of CDK5, was studied in rat cortical neurons in primary culture. Treatment of cultured neurons with cyclohexamide induced the rapid disappearance of p35 accompanied by parallel inactivation of the kinase activity of CDK5. The disappearance of p35 was blocked with proteasome inhibitors benzyloxycarbonyl-leucyl-leucyl-leucinal and lactacystin, indicating the involvement of proteasome. The degradation of p35 was induced with okadaic acid in the presence of ATP in neuron extracts. The degradation of p35 by proteasome in cultured neurons was stimulated by okadaic acid in the absence of cyclohexamide. These results indicate that p35 is degraded by proteasome in a phosphorylation-dependent manner in neurons.
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96
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Lao LM, Kumakiri M, Mima H, Kuwahara H, Ishida H, Ishiguro K, Fujita T, Ueda K. The ultrastructural characteristics of eccrine sweat glands in a Fabry disease patient with hypohidrosis. J Dermatol Sci 1998; 18:109-17. [PMID: 9833977 DOI: 10.1016/s0923-1811(98)00032-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
As an investigation of the pathogenetic mechanism of diminished sweating in Fabry disease, an electron microscopy ultrastructural study was conducted on specimens of eccrine sweat glands from a typical patient with Fabry disease who had hypohidrosis, a low skin moisture content, and diminished thermoregulation ability. Numerous characteristic cytoplasmic inclusions were observed in the eccrine sweat glands, the lamellar pattern of which was considerably variable in various types of gland cells. Large vacuolar inclusions predominated in clear cells of secretory coil; lesser vacuoles were also seen in the coiled duct, and the basal cells of the straight duct toward the coiled duct displayed mulberry-like figures. There were some clear cells showing cell damage and necrosis in the secretory coil. Lamellated inclusions were noted in the unmyelinated axons innervating the eccrine sweat glands. The small blood vessels around the eccrine glands were narrowed by swollen endothelial cells with heavy inclusions. These intracytoplasmic deposits may be responsible for the decreased sweating ability in Fabry disease. The factors related to hypohidrosis are also discussed.
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97
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Lin TS, Ishiguro K, Sartorelli AC. Role of gp55 in restoring the sensitivity of Friend murine erythroleukemia cells to erythropoietin by exposure to dimethyl sulfoxide. Oncol Res 1998; 10:175-84. [PMID: 9778688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Although Friend murine erythroleukemia (MEL) cells express the erythropoietin receptor (EpoR), they are insensitive to erythropoietin (Epo). The nonresponsiveness to Epo presumably results from gp55, the product of the env gene encoded by the Friend spleen focus-forming virus (F-SFFV), acting as a pseudoligand and constitutively activating the receptor. Dimethyl sulfoxide (DMSO) induced the differentiation of MEL cells and partially restored responsiveness to Epo, with both increased proliferation and further hemoglobin synthesis. Treatment of MEL cells with DMSO caused a decrease in the cellular content of gp55 as measured by Western analysis and an increase in the level of the EpoR as measured by [125I]Epo binding. These changes were produced at least in part at the transcriptional level, because DMSO treatment caused a decrease and an increase in the levels of the mRNAs for gp55 and EpoR, respectively. To ascertain the role of gp55 in the restoration of the sensitivity of MEL cells to Epo by exposure to DMSO, expression vectors containing gp55 DNA in the sense and antisense orientations were transfected into MEL cells to increase or decrease, respectively, the amount of cellular gp55. An increase in the level of gp55 interfered with the ability of DMSO to restore sensitivity to Epo, whereas a decrease in the level of gp55 increased the Epo-sensitizing effects of DMSO. [125I]Epo was chemically cross-linked to a component with a calculated molecular weight of 65 kDa. DMSO treatment caused an increase in the level of [125I]Epo cross-linking. The protein cross-linked to Epo was immunoprecipitated with anti-EpoR serum but not with anti-gp55 serum, suggesting that Epo was cross-linked to its receptor. The finding of a decrease in the cellular content of gp55, an increase in the level of the EpoR, and an increase in the formation of the Epo/EpoR complex is consistent with the acquisition of sensitivity to Epo by MEL cells following treatment with DMSO.
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98
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Ishiguro K. [Involvement of tau protein kinase in amyloid-beta-induced neurodegeneration]. RINSHO BYORI. THE JAPANESE JOURNAL OF CLINICAL PATHOLOGY 1998; 46:1003-7. [PMID: 9816911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Abstract
Histopathological features of Alzheimer's disease (AD) include extracellular deposits of amyloid beta (A beta) fibrils in the cores of senile plaques, intracellular neurofibrillary tangles (NFT) which are composed of paired helical filaments (PHF), and neuronal cell loss. The main component of PHF is highly phosphorylated tau protein. We identified a protein kinase converting normal tau into a PHF-like state. The kinase is tau protein kinase (TPK) I/glycogen synthase kinase (GSK)-3 beta. Using a neuronal cell culture system as an AD model, it was recognized that TPK I/GSK-3 beta plays a central role in AD pathology. We hypothesize that A beta-induced neuronal cell death occurs by the following mechanism. A beta inactivates PI3-kinase and activates TPK I/GSK-3 beta, which in turn phosphorylates and inactivates both tau and pyruvate dehydrogenase (PDH). After the ability of tau to promote microtubule assembly is diminished by phosphorylation, soluble tau molecules aggregate into PHF by an unknown mechanism. Destabilization of microtubule arrays causes inhibition of axonal transport and accumulation of amyloid precursor protein (APP). Phosphorylation of PDH inhibits the reaction converting pyruvate to acetyl-CoA, resulting in inhibition of energy metabolism and a decrease in acetylcholine, both of which are also characteristics of AD. These changes may lead to neuronal cell death.
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99
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Wada Y, Ishiguro K, Itoh TJ, Uchida T, Hotani H, Saito T, Kishimoto T, Hisanaga S. Microtubule-stimulated phosphorylation of tau at Ser202 and Thr205 by cdk5 decreases its microtubule nucleation activity. J Biochem 1998; 124:738-46. [PMID: 9756618 DOI: 10.1093/oxfordjournals.jbchem.a022174] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Phosphorylation of tau, a heat-stable neuron-specific microtubule-associated protein, by cdk5 was stimulated in the presence of microtubules (MTs). This stimulation was due to an increased phosphorylation rate and there was no increase in total amount of phosphorylation. Two-dimensional phosphopeptide map analysis showed that MTs stimulated phosphorylation of a specific peptide. Using Western blotting with antibodies that the recognized phosphorylation-dependent epitopes within tau, the phosphorylation sites stimulated by the presence of MTs were found to be Ser202 and Thr205 (numbered according to the human tau isoform containing 441 residues). MT-dependent phosphorylation at Thr205 was observed in situ in rat cerebrum primary cultured neurons. Stimulated phosphorylation at Ser202 and Thr205 decreased the MT-nucleation activity of tau, which is in contrast to MT-independent phosphorylation at Ser235 and Ser404.
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100
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Ishiguro K, Ohira Y, Oku H. Antipruritic dinaphthofuran-7,12-dione derivatives from the pericarp of Impatiens balsamina. JOURNAL OF NATURAL PRODUCTS 1998; 61:1126-1129. [PMID: 9748380 DOI: 10.1021/np9704718] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Dinaphthofuran-7,12-dione derivatives named balsaminones A (1) and B (2) were isolated from the pericarp of Impatiens balsamina L. together with the known compound 2-methoxy-1,4-naphthoquinone (3). Their structures were elucidated by spectral techniques. These compounds have significant antipruritic activity.
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