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K Irie

Publications and source records attributed to K Irie.

At least 127 records · Page 7Linked to original sources
PubMed1996

Genetic interaction of DED1 encoding a putative ATP-dependent RNA helicase with SRM1 encoding a mammalian RCC1 homolog in Saccharomyces cerevisiae.

The Saccharomyces cerevisiae temperature-sensitive mutants srm1-1, mtr1-2 and prp20-1 carry alleles of a gene encoding a homolog of mammalian RCC1. In order to identify a protein interacting with RCC1, a series of suppressors of the srm1-1 mutation were isolated as cold-sensitive mutants and one of the mutants, designated ded1-21, was found to be defective in the DED1 gene. The double mutant, srm1-1 ded1-21, could grow at 35 degrees C, but not at 37 degrees C. A revertant of srm1-1 ded1-21 that became able to grow at 37 degrees C acquired another mutation in the SRM1 gene, indicating the tight relationship between SRM1 and DED1. In all the rcc1- strains examined, the amount of mutated SRM1 proteins was reduced or not detectable at the nonpermissive temperature. While mutated SRM1 protein was stabilized in all of the rcc1- strains by the ded1-21 mutation, the ded1-21 mutation suppressed both srm1-1 and mtr1-2, but not the prp20-1 mutation, contrary to the previous finding that overproduction of the S. cerevisiae Ran homolog GSP1 suppresses prp20-1, but not srm1-1 or mtr1-2.

Cell Cycle Proteins↗
PubMed1996

Purification and identification of a major activator for p38 from osmotically shocked cells. Activation of mitogen-activated protein kinase kinase 6 by osmotic shock, tumor necrosis factor-alpha, and H2O2.

A stress-activated, serine/threonine kinase, p38 (also known as HOG1 or MPK2) belongs to a subgroup of mitogen-activated protein kinase (MAPK) superfamily molecules. An activity to activate p38 (p38 activator activity) as well as p38 activity itself were greatly stimulated by hyperosmolar media in mouse lymphoma L5178Y cells. The activator activity has been purified by sequential chromatography. A 36-kDa polypeptide that was coeluted with the activity in the final chromatography step was identified as MAPK kinase 6 (MAPKK6) by protein microsequencing analysis. Monoclonal and polyclonal antibodies raised against recombinant MAPKK6 recognized specifically the 36-kDa MAPKK6 protein but did not cross-react with MKK3 proteins. The use of these anti-MAPKK6 antibodies revealed that two major peaks of the p38 activator activity in the first chromatography step reside in the activated MAPKK6. Using a genetic screen in yeast, we isolated MKK3b, an alternatively spliced form of MKK3. Like MKK3 and MAPKK6, MKK3b was shown to be a specific activator for p38 and was activated by osmotic shock when expressed in COS7 cells. Immunoblotting analysis revealed that MAPKK6 is expressed highly in HeLa and KB cells and scarcely in PC12 cells, whereas MKK3 and MKK3b are expressed in all cells examined. Immunodepletion of MAPKK6 from the extracts obtained from L5178Y cells and KB cells exposed to hyperosmolar media depleted them of almost all of the p38 activator activity, indicating that MAPKK6 is a major activator for p38 in an osmosensing pathway in these cells. In addition, MAPKK6 was activated strongly by tumor necrosis factor-alpha, H2O2, and okadaic acid and moderately by cycloheximide in KB cells. Thus, there are at least three members of p38 activator, MKK3, MKK3b, and MAPKK6, and MAPKK6 may function as a major activator for p38 when expressed.

Amino Acid Sequence↗
PubMed1996

Tolerance to lipopolysaccharide-induced increase in vascular permeability in mouse skin.

We investigated whether tolerance develops to the lipopolysaccharide-induced increase in vascular permeability of mouse skin on pretreatment with Salmonella typhimurium lipopolysaccharide. Lipopolysaccharide-induced plasma extravasation was assessed by determining Pontamine sky blue dye accumulation in the skin where lipopolysaccharide was injected s.c. 2 h previously. When mice were pretreated with lipopolysaccharide (0.15 mg/kg i.p.), the dye leakage induced by s.c. challenge with lipopolysaccharide (400 micrograms/site) was significantly, inhibited for 2-24 h after pretreatment, indicating the development of lipopolysaccharide tolerance. At 4 h after lipopolysaccharide (0.15 mg/kg i.p.), the dose-response curve of dye leakage against the challenge dose of lipopolysaccharide shifted about 2-fold to the higher dose. The dye leakage induced by lipopolysaccharide was inhibited by pretreatment with lipopolysaccharide in a dose-dependent manner (0.05-0.15 mg/kg i.p.). Lipopolysaccharide tolerance was not seen in adrenalectomized mice. When mice were pretreated with lipopolysaccharide and NG-nitro-L-arginine methyl ester (L-NAME), a nitric oxide (NO) synthase inhibitor, at the same time, the hyporesponsiveness to lipopolysaccharide challenge disappeared. However, L-NAME was ineffective to inhibit the development of lipopolysaccharide tolerance when administered 24 h after lipopolysaccharide pretreatment or just before the lipopolysaccharide challenge. Tumor necrosis factor-alpha and interleukin-1 alpha but not interleukin-6 induced a similar hyporesponsiveness to lipopolysaccharide. These results suggest that tolerance develops to the lipopolysaccharide-induced increase in vascular permeability in mouse skin after a single lipopolysaccharide administration and that endogenous glucocorticoids and NO are necessary for induction of lipopolysaccharide tolerance. Hyporesponsiveness induced by lipopolysaccharide pretreatment may be mediated by production of some cytokines such as tumor necrosis factor-alpha or interleukin-1 alpha.

Animals↗
PubMed1996

A novel kinase cascade mediated by mitogen-activated protein kinase kinase 6 and MKK3.

A cDNA encoding a novel member of the mitogen-activated protein kinase kinase (MAPKK) family, MAPKK6, was isolated and found to encode a protein of 334 amino acids, with a calculated molecular mass of 37 kDa that is 79% identical to MKK3. MAPKK6 was shown to phosphorylate and specifically activate the p38/MPK2 subgroup of the mitogen-activated protein kinase superfamily and could be demonstrated to be phosphorylated and activated in vitro by TAK1, a recently identified MAPKK kinase. MKK3 was also shown to be a good substrate for TAK1 in vitro. Furthermore, when co-expressed with TAK1 in cells in culture, both MAPKK6 and MKK3 were strongly activated. In addition, co-expression of TAK1 and p38/MPK2 in cells resulted in activation of p38/MPK2. These results indicate the existence of a novel kinase cascade consisting of TAK1, MAPKK6/MKK3, and p38/MPK2.

Amino Acid Sequence↗
PubMed1996

TAB1: an activator of the TAK1 MAPKKK in TGF-beta signal transduction.

Transforming growth factor-beta (TGF-beta) regulates many aspects of cellular function. A member of the mitogen-activated protein kinase kinase kinase (MAPKKK) family, TAK1, was previously identified as a mediator in the signaling pathway of TGF-beta superfamily members. The yeast two-hybrid system has now revealed two human proteins, termed TAB1 and TAB2 (for TAK1 binding protein), that interact with TAK1. TAB1 and TAK1 were co-immunoprecipitated from mammalian cells. Overproduction of TAB1 enhanced activity of the plasminogen activator inhibitor 1 gene promoter, which is regulated by TGF-beta, and increased the kinase activity of TAK1. TAB1 may function as an activator of the TAK1 MAPKKK in TGF-beta signal transduction.

Adaptor Proteins, Signal Transducing↗
PubMed1996

Role of nitric oxide and prostaglandins in lipopolysaccharide-induced increase in vascular permeability in mouse skin.

To examine the possible role of increased vascular permeability in the circulatory shock induced by endotoxin (lipopolysaccharide), we examined whether lipopolysaccharide elicits plasma extravasation in the skin of ddY strain mice. We also studied whether nitric oxide (NO) and prostaglandins may mediate the lipopolysaccharide-induced increase in vascular permeability. Subcutaneous injection of lipopolysaccharide (100-400 micrograms/site) induced a dose-related and delayed increase in vascular permeability at the injection site as determined by the leakage of pontamine sky blue. Concurrent administration of aminoguanidine (a putative inducible NO synthase inhibitor) (10 mg/kg, i.v.) inhibited the lipopolysaccharide (400 micrograms/site)-induced dye leakage by 71%. N(G)-Nitro-L-arginine methyl ester (an inhibitor for both constitutive and inducible NO synthase) (10 and 20 mg/kg, i.v.) inhibited the lipopolysaccharide-induced dye leakage by 36% and 54%, respectively, whereas the inactive enantiomer, N(G)-nitro-D-arginine methyl ester (10 mg/kg, i.v.), had no effect. Pretreatment with an intraperitoneal injection of dexamethasone (500 micrograms/kg) or indomethacin (a cyclooxygenase-1 and -2 inhibitor) (5 mg/kg) almost completely inhibited the response induced by lipopolysaccharide, by 96% and 84%, respectively. [N-(2-Cyclohexyloxy-4-nitrophenyl) methanesulphonamide (a cyclooxygenase-2-specific inhibitor) (0.01-1 mg/kg, i.p.) also induced a dose-related inhibition of dye leakage elicited by lipopolysaccharide: 38% and 80% suppression at the doses of 0.1 and 1 mg/kg, respectively. Cycloheximide (a protein biosynthesis inhibitor) (35 mg/kg, s.c.) suppressed the effect of lipopolysaccharide by 74%. These results suggest that the increase in vascular permeability induced by lipopolysaccharide is mediated by both NO and prostaglandins and that synthesis of inducible NO synthase and cyclooxygenase-2 may be involved in this effect of lipopolysaccharide.

Animals↗
PubMed1996

A gene encoding a mitogen-activated protein kinase kinase kinase is induced simultaneously with genes for a mitogen-activated protein kinase and an S6 ribosomal protein kinase by touch, cold, and water stress in Arabidopsis thaliana.

We describe here the cloning and characterization of a cDNA encoding a protein kinase that has high sequence homology to members of the mitogen-activated protein kinase (MAPK) kinase kinase (MAPKKK or MEKK) family; this cDNA is named cATMEKKI (Arabidopsis thaliana MAP kinase or ERK kinase kinase 1). The catalytic domain of the putative ATMEKK1 protein shows approximately 40% identity with the amino acid sequences of the catalytic domains of MAPKKKs (such as Byr2 from Schizosaccharomyces pombe, Ste11 from Saccharomyces cerevisiae, Bck1 from S. cerevisiae, MEKK from mouse, and NPK1 from tobacco). In yeast cells that overexpress ATMEKK1, the protein kinase replaces Ste11 in responding to mating pheromone. In this study, the expression of three protein kinases was examined by Northern blot analyses: ATMEKK1 (structurally related to MAPKKK), ATMPK3 (structurally related to MAPK), and ATPK19 (structurally related to ribosomal S6 kinase). The mRNA levels of these three protein kinases increased markedly and simultaneously in response to touch, cold, and salinity stress. These results suggest that MAP kinase cascades, which are thought to respond to a variety of extracellular signals, are regulated not only at the posttranslational level but also at the transcriptional level in plants and that MAP kinase cascades in plants may function in transducing signals in the presence of environmental stress.

Amino Acid Sequence↗
PubMed1996

Transgenic rice established to express corn cystatin exhibits strong inhibitory activity against insect gut proteinases.

Corn cystatin (CC), a phytocystatin, shows a wide inhibitory spectrum against various cysteine proteinases. We produced transgenic rice plants by introducing CC cDNA under CaMV 35S promoter as a first step to obtain a rice plant with insecticidal activity. This attempt was based on the observation that many insect pests, especially Coleoptera, have cysteine proteinases, probably digestive enzymes, and also that oryzacystatin, an intrinsic rice cystatin, shows a narrow inhibition spectrum and is present in ordinary rice seeds in insufficient amounts to inhibit the cysteine proteinases of rice insect pests. The transgenic rice plants generated contained high levels of CC mRNA and CC protein in both seeds and leaves, the CC protein content of the seed reaching ca. 2% of the total heat soluble protein. We also recovered CC activity from seeds and found that the CC fraction efficiently inhibited both papain and cathepsin H, whereas the corresponding fraction from non-transformed rice seeds showed much lower or undetectable inhibitory activities against these cysteine proteinases. Furthermore, CC prepared from transgenic rice plants showed potent inhibitory activity against proteinases that occur in the gut of the insect pest, Sitophilus zeamais.

Animals↗
PubMed1996

A case of malignant fibrous histiocytoma of the ilium, evaluation by blood-pool scintigraphy.

A rare case of malignant fibrous histiocytoma (MFH) of the ilium was presented and blood-pool scintigraphic images and angiographic images were correlated. Hypervascular tumor and lacking of contrast material with arteriovenous shunts were shown by angiography. Intensive tracer accumulation was shown by blood-pool scintigraphy. After radiation therapy and transcatheter arterial embolization of the tumor, tracer accumulation was noticeable reduced. These findings suggested a vascular tumor such as angiosarcoma, but surgery revealed MFH of the bone. Blood-pool scintigraphy was useful in the evaluation of the vascular characteristics of the tumor.

Aged↗
PubMed1996

Long-term evaluation of recombinant human bone morphogenetic protein-2 induced bone formation with a biologic and synthetic delivery system.

The efficacy of microspheres made of polylactic acid polyglycolic acid copolymer mixed with blood clot as a delivery system for recombinant human bone morphogenetic protein-2 (rhBMP-2) was evaluated and the long term behaviour of rhBMP-2 in rats was studied. Twenty micro grams of rhBMP-2 in 200 microliter carrier (blood coagulum and polylactic acid polyglycolic acid porous microspheres) were implanted subcutaneously over both sides of the chest muscles in 40 5-week-old male Long Evans rats. The control group were implanted with carrier alone. Specimens were retrieved after 3 days and weekly for 9 weeks. Outcome was measured by signs of bone formation on low power radiographs, and signs of bony growth on histological examination. There were no signs of foreign body or inflammatory reactions to the carrier in either group. In the experimental group signs of bone formation had started to appear by the end of the first week, and there was a gradual increase in both radio-opacity and size during the observation period. Histologically the bony growth was beginning to mature by 4 weeks and was fully mature by 7-9 weeks. In contrast there was no sign of cartilage or bone formation in the control group and the carrier had resorbed by 4-6 weeks. It is concluded that rhBMP-2 implanted in a carrier consisting of blood clot and porous microspheres made of polylactic acid polyglycolic acid induces rapid proliferation of mesenchymal cells that lead to formation of cartilage and bone by 7 days which had matured by 9 weeks. rhBMP-2 in this carrier may be useful clinically because of its capacity to induce early formation of bone.

Animals↗
PubMed1996

Transvenous embolization of traumatic carotid cavernous fistula with mechanical detachable coils.

An attempt at transarterial balloon embolization of a traumatic carotid cavernous fistula was made but the carotid artery rent was too small for this approach. The patient was then treated by antegrade embolization through a superior ophthalmic vein using mechanical detachable coils. Successful obliteration of the fistula was achieved with preservation of the carotid artery. Transvenous embolization is an alternative technique to treat patients with traumatic carotid cavernous fistulas, especially when a transarterial approach has failed.

Adult↗
PubMed1996

Cerebral vasospastic vessels: histologic changes after percutaneous transluminal angioplasty.

PURPOSE: To investigate histologic changes before and after percutaneous transluminal angioplasty (PTA) in experimental cerebral vasospasm in comparison with normal vessels. MATERIALS AND METHODS: In seven monkeys, vasospasm was induced in the subarachnoid space. After 7 days, PTA was performed. Microscopic studies were performed in vasospastic vessels. In two animals, vasospasm was induced but angioplasty was not performed. The controls were two animals without vasospasm who underwent only contralateral angioplasty. RESULTS: Angiography after vasospasm revealed marked narrowing but dilatation after PTA, without changes in distal spastic vessels. Specimens after PTA showed platelets that covered denuded endothelium, stretching, and focal dehiscence of internal elastic lamina and altered myocytes in media. Myocytes were deformed and arranged irregularly. These changes were not uniform. CONCLUSION: The prolonged effect of PTA may be caused by mechanical damage of myocytes and the nonuniformity of histologic changes in vascular walls.

Angioplasty, Balloon↗
PubMed1996

Effect of S-ethylisothiourea, a putative inhibitor of inducible nitric oxide synthase, on mouse skin vascular permeability.

By dye leakage in mouse skin, we evaluated the inhibition of proinflammatory stimuli-induced plasma extravasation by a putative inhibitor of inducible nitric oxide synthase, S-ethylisothiourea. A low dose of S-ethylisothiourea (5 micrograms/kg) mimicked aminoguanidine in inhibiting the plasma extravasation elicited by lipopolysaccharide but not by 5-hydroxytryptamine or platelet-activating factor. A higher dose of S-ethylisothiourea (10 micrograms/kg) inhibited the plasma extravasation induced by 5-hydroxytryptamine slightly; however, it increased the basal dye leakage. Thus, S-ethylisothiourea may be used as a relatively specific inhibitor for inducible nitric oxide synthase in vivo.

Animals↗
PubMed1996

Photocytotoxicity of water-soluble fullerene derivatives.

New water-soluble fullerene carboxylic acids (1 and 2) derived from C60 and C70 fullerenes, respectively, were examined for photocytotoxicity toward Raji cells (B lymphocyte). These compounds did not show any photocytotoxic effect even at 50 microM, while pheophorbide a showed significant photocytotoxicity at 0.5 microM. Therefore, fullerene derivatives derived from C60 and C70 would not be practical agents for photodynamic therapy.

B-Lymphocytes↗
PubMed1996

Incidence of methicillin-resistant Staphylococcus aureus (MRSA) isolation in a skilled nursing home: a third report on the risk factors for the occurrence of MRSA infection in the elderly.

A case control study was carried out in order to evaluate the various factors which may influence the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) infections in a skilled nursing home. From April 1991 to March 1994, bacterial cultures were performed in 55 out of 102 residents in a nursing home based on various clinical aspects. We divided 102 residents into following three groups; (1) the MRSA group (n = 10), residents whose materials for bacterial culture were positive for MRSA, (2) the non-MRSA group (n = 45), residents whose specimens were negative for MRSA but positive for other bacteria, (3) the control group (n = 47), residents who did not have to undergo a bacterial culture because they were free from moderate and severe infectious diseases. Compared with the control group, the activities of daily living score and the serum albumin level were significantly lower in the MRSA group and the non-MRSA group at the beginning of the study. In contrast, the number of antibiotics used prior to the bacterial culture and the proportion of hospitalization within 6 months prior to the bacterial culture were significantly larger in the MRSA group than in either the non-MRSA group, or the control group. These results thus suggest that a low activities of daily living score, the use of many kinds of antibiotics and a recent previous hospitalization may be risk factors of MRSA infection in a nursing home environment.

Aged↗
PubMed1996

[Clinicopathological study on primary lung cancer--immunohistochemical expression of p53 suppressor gene and bcl-2 oncogene in relation to prognosis].

Two hundred and eleven surgically resected primary lung tumors were studied immunohistochemically. According to histologic type, they were 129 adenocarcinomas, 56 squamous cell carcinomas, 4 small cell carcinomas, 8 large cell carcinomas, 8 adenosquamous cell carcinomas, 5 so-called carcinosarcomas and 2 other tumors. Immunohistochemical expression of p53 and bcl-2 was studied in relation to the disease-free survival. Among the 211 patients with lung cancer, 109 were positive for p53 expression, and there was no significant relationship between p53 expression and sex, or clinicopathological stage and size of the tumor, although the patients with squamous cell carcinoma had a significantly higher frequency of p53 expression than those with adenocarcinomas. The frequency of p53 expression was significantly higher in the patients with poorly differentiated adenocarcinomas than in those with other histologic types. Seventy four of the 211 patients were positive for bcl-2 expression and bcl-2 expression was higher in the stage I patients and patients with small lung tumors 2cm or less in diameter than in the other patients. The patients with adenocarcinoma had a higher frequency of expression than those with squamous cell carcinoma but no difference was found in the histological differentiation of the tumor. The 5-year survival of patients positive for p53 expression was poorer than that of those with negative expression and the survival rate was higher in the patients positive for bcl-2 expression than in those with negative expression. These findings suggested that the expression of p53 and bcl-2 is a useful marker of follow-up and prognosis, but will require more data concerning the mechanism of carcinogenesis. Seven cases of primary lung cancer were examined for genetic abnormality of the p53 gene. cDNA was synthesized from total RNA of primary tissues of lung cancer using oligo (dT) primer and reverse transcriptase and polymerase chain reaction (RT-PCR), and PCR-single strand conformation polymorphism (SSCP) analysis were performed. Five patients gave a positive result upon PCR-SSCP analysis of the p53 gene. To confirm the results of PCR-SSCP analysis, their nucleotide sequences were further analyzed and four of them had point mutations at different codons (154, 176, 207, 236) and one had deletion of one nucleotide (245) in exon 5 and 8. Fifteen percent of 26 patients with small peripheral lung adenocarcinomas less than 2cm in diameter were already advanced in stage and various factors such as vascular invasion, pleural involvement and degree of scar grade were higher than in patients with clinicopathological stage I. In advanced cases, the frequencies of p53 expression was higher than in stage I cases. Concerning the relationship of the degree of scar grade to PDGF-B expression, we demonstrated the production of PDGF-B protein immunohistochemically and the expression of PDGF-B-mRNA by In situ hybridization in the adenocarcinoma cells and macrophages of the lung tumors. However, no significant correlation was observed between the degree of PDGF-B expression and collagen production in the fibrotic focus.

Adenocarcinoma↗