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K Konishi

Publications and source records attributed to K Konishi.

At least 19 recordsLinked to original sources
PubMed1992

Microenvironment of tryptophan residues in beta-lactoglobulin derivative polypeptide-sodium dodecyl sulfate complexes.

The changes of microenvironment of tryptophan residues in beta-lactoglobulin A and its cyanogen bromide (CNBr) fragments with the binding of sodium dodecyl sulfate (SDS) were studied with measurements of the rates of N-bromosuccinimide (NBS) modification reactions by stopped-flow photometry. Two tryptophan residues of carboxyamidomethylated (RCM) beta-lactoglobulin A in the states of their complexes with SDS were clearly distinguishable by their differences in NBS modification rates. We confirmed by experiments with CNBr fragments containing trytophan residue. The modification rates of Trp 19 in RCM beta-lactoglobulin A-SDS complexes were about 10-fold smaller than those expected for tryptophan residues exposed entirely to the aqueous solvent. The Trp 61 was hardly changed. The change of rate constants for Trp 19 was virtually consistent with those observed when N-acetyl-L-trytophan ethylester was dissolved in SDS micelles. For various species of polypeptide-SDS complexes, all tryptophan residues were reactive to NBS and also, for some of them, the differences in NBS modification rates were observed between tryptophan residues on a common polypeptide chain. These results suggest micellar and heterogeneous bindings of SDS to polypeptides.

Cyanogen Bromide↗
PubMed1992

Rat gro/melanoma growth-stimulating activity. Assessment of the structure responsible for chemotactic activity by use of its fragments prepared by proteolysis and chemical synthesis.

Rat gro/melanoma growth-stimulating activity is a dimer composed of two identical subunits. Each subunit consists of 72 amino-acid residues and contains two disulfide bridges. In order to obtain information on the structure responsible for chemotactic activity, various fragments of gro were prepared and tested for their ability to induce chemotaxis. None of the fragments corresponding to residues 1-6, 1-21, 12-31, 36-50 or 52-72 was active as a chemoattractant. Reduced and carboxymethylated gro as well as the tryptic peptide consisting of three peptides, residues 9-21, 28-45 were and 49-61, linked by two disulfide bonds Cys-9-Cys-35 and Cys-11-Cys-51, were inactive. Also, these, peptides did not inhibit the chemotactic activity of gro. Rat gro lacking the N-terminal 6 residues had a reduced activity and the one lacking the C-terminal Lys was as active as intact gro. Therefore, an almost entire portion of the molecule including disulfide cross-links is required for chemotactic activity.

Amino Acid Sequence↗
PubMed1992

Isolation and characteristics of scallop sarcoplasmic reticulum with calcium transport activity.

Sarcoplasmic reticulum with calcium transport activity has been isolated from the cross-striated adductor muscle of the scallop, which lives in cold (< or = 20 degrees C) sea water, by using pH 7.0 buffer solution both to homogenize the tissue and to sediment the membrane fraction. The yield of the preparation was 60-100 mg protein from 100 g of the scallop muscle. Ca(2+)-activated ATPase protein of about 100 kDa accounted for 40-50% of the protein preparation. The maximum activities of ATP-dependent, oxalate-facilitated calcium accumulation and Ca(2+)-ATPase were observed at a pH of about 7.0 and temperature of 20-30 degrees C, and their values were about 2 mumol Ca2+/mg of protein/min and about 3 mumol ATP hydrolysis/mg of protein/min, respectively. At 0 degree C, 10-20% of these activities was maintained, while at 37 degrees C, the activities were irreversibly lost. The Ca(2+)-ATPase activity was half-maximally activated at about 0.3 microM [Ca2+]. The ATPase activity exhibited non-Michaelian behavior with respect to ATP, with two different Km values of approximately 10 microM and 0.1-0.3 mM. GTP, CTP, and ITP were also hydrolyzed by the preparation at a rate of 10-30% of that of ATP. The preparation was stored at -80 degrees C with retention of function for about a year.

Adenosine Triphosphate↗
PubMed1992

Increased glycated Cu,Zn-superoxide dismutase levels in erythrocytes of patients with insulin-dependent diabetis mellitus.

Our previous study indicated that erythrocyte Cu,Zn-superoxide dismutase (Cu,Zn-SOD) undergoes glycation and inactivation in vivo (1) and in vitro (2). The aim of the present study was to assess glycated Cu,Zn-SOD in patients with insulin-dependent diabetes mellitus. Glycated Cu,Zn-SOD, which binds to a boronic acid affinity column, was measured by the enzyme-linked immunosorbent assay. The percentage of the glycated form in 25 insulin-dependent diabetic children was 40.2 +/- 8.2%; this was significantly higher than that in the normal controls (P less than 0.01). The specific activity of the glycated form in the diabetic children was 163,000 +/- 33,000 IU/mg Cu,Zn-SOD protein, significantly lower than that in controls (P less than 0.01). These data indicate that glycated and less active Cu,Zn-SOD is increased in erythrocytes of patients with insulin-dependent diabetes mellitus.

Adult↗
PubMed1992

Histopathological factors related to diastolic function in myocardial hypertrophy.

To clarify the histopathologic influence on diastolic function in the hypertrophied heart, we compared the echocardiographic and histopathologic findings in 9 controls, 10 patients with hypertrophic cardiomyopathy (HCM), and 8 hypertensive patients with asymmetric septal hypertrophy (HT-ASH). M-mode echocardiography was used to determine the left ventricular diastolic function. Mean diameter of myocytes, percentage of fibrosis and disarrangement were quantitatively calculated from right ventricular endomyocardial biopsy specimens. In both HT-ASH and HCM, the isovolumic relaxation time was significantly longer and the rapid filling volume tended to be smaller than in the controls. Histopathologically, the mean diameter of myocytes and percentage of myocardial interstitial fibrosis did not differ significantly between HT-ASH and HCM. However, quantitative disarrangement of myocytes in HCM was significantly greater than that in HT-ASH. Multiple regression analysis showed that the percentage of fibrosis was the most significant factor related to diastolic left ventricular dysfunction in HT-ASH, while disarrangement of myocytes was the most significant in HCM. We conclude that diastolic dysfunction in HT-ASH can be attributed to the percentage of fibrosis, and to disarrangement of myocytes in HCM.

Adult↗
PubMed1992

[Treatment of infantile spasms with long-term low dose ACTH].

We investigated the effect of long-term, low-dose ACTH in 13 patients (10 boys and 3 girls) with infantile spasms who were treated with low-dose ACTH (mean: 0.0081 mg/kg/day). Two patients (one boy and one girl) received this therapy twice because of relapse of tonic spasms. ACTH was injected intramuscularly every morning for 30 days, after which dosage was tapered. The mean observation period was 53.9 months. Complete cessation of seizures was attained in 13 of 15 treatment trials. In one trial, complete cessation was not attained but the number of attacks decreased to less than one-third of that before treatment. In only one trial was treatment not effective. EEG showed good response to this treatment. The side-effects of this therapy were hypertension in 6 patients, hypokalemia in 7, and emotional outburst in 7. Emotional outburst appeared during the early phase of therapy, while the other two side-effects appeared in the later phase and disappeared when ACTH-tapering was begun. Brain shrinkage observed on CT scan was mild in all trials. Five patients have had no relapse. The total dose of ACTH was significantly larger in the group with good outcome than in the group with poor outcome.

Adrenocorticotropic Hormone↗
PubMed1992

[A study of chest X-ray classification of farmer's lung--correlation between X-ray pattern and background factors].

Patients with farmer's lung were classified into five groups according to their chest X-ray pattern, and the background of each group was studied with respect to stage, severity, and prognosis. Type I group, which has fine nodular shadows on chest X-ray, showed a significantly high percentage of lymphocytes in BAL cells (p less than 0.01). Type V group, which has irregular patchy shadows on chest X-ray, showed increased peripheral WBC counts, increased CRP score, and decreased PaO2 compared to the other groups. Type II, III, and IV groups, which are characterized by combined X-ray patterns such as nodular shadows, ring-like shadows, and irregular pulmonary markings, had no specific background features according to our study. Our results suggest that type I and type V groups are likely to represent acute phase and severe phase, respectively. We could not identify any significant factors indicative of chronic disease in terms of restrictive and diffusion impairment of pulmonary function tests and pathologic findings obtained by TBLB. The chest X-ray classification we proposed is useful for the diagnosis of the acute and severe stages of farmer's lung.

Adult↗
PubMed1992

[Cytokine gene expression in interstitial lung diseases].

We studied the role of macrophages in the process of pulmonary fibrosis, focusing on gene expressions of cytokines. TGF-alpha is a factor which stimulates fibroblasts or endothelial cells to proliferate, by combining to receptors of EGF competitively with EGF in vitro. Total RNA was extracted from alveolar macrophages recovered by bronchoalveolar lavage from patients with idiopathic pulmonary fibrosis or normal healthy volunteers, and the expression of TGF-alpha mRNA was evaluated by Northern analysis. There was no detectable TGF-alpha mRNA in alveolar macrophages from normal healthy volunteers; however, in patients with idiopathic pulmonary fibrosis, a considerable level of mRNA of TGF-alpha could be detected. Using an experimental rat model of alveolitis induced by bleomycin, the expression of TNF-alpha mRNA in alveolar macrophages recovered by BAL was evaluated by Northern analysis. Alveolar macrophages from bleomycin-treated rats expressed a significant level of TNF-alpha mRNA. Both TGF-alpha and TNF-alpha have proliferative activity on fibroblasts, and may have an important role in the process of fibrosis of the lung.

Cell Division↗
PubMed1992

[A case of gastric cancer with multiple liver metastases effectively treated with PMUE (CDDP, MMC, UFT, etoposide) hepatic arterial chemotherapy].

A 62-year-old male patient with progressive gastric cancer and multiple liver metastases (H3, P0, ss gamma, n4) underwent total gastrectomy (R1). After 2 years and 2 months, he was re-hospitalized with epigastric tumor caused by re-manifestation of liver metastasis as well as inappetence. Since a large focus of liver metastasis and intraportal tumor embolism was identified, a continuous intraarterial infusion tube utilizing Infuse-A-Port was inserted in the hepatic artery. After conducting 2 cycles of PMUE intra-arterial chemotherapy, the tumor size was reduced by 84% (PR); and CEA, which had been high upon rehospitalization, recovered to the normal level. After discharge, the patient has been receiving 5-FU arterial infusion as an outpatient and undergoing UFT oral chemotherapy. The efficacy has continued and he has been well for 3 years since operation. Often operations for gastric cancer accompanied with multiple liver metastasis meet with little success, and almost no case of prolonged survival has been reported. In this case, the effectiveness of PMUE arterial infusion chemotherapy was clear, the patient has been well for 3 years since operation, and is an interesting example with seemingly good prospects for long-survival.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

[A case of myocardial infarction in a young man with systemic lupus erythematosus].

Apparently the incidence of coronary artery disease in systemic lupus erythematosus (SLE) has been increasing. However, most of the cases had been treated with corticosteroids, and had atherosclerotic lesions in the coronary arterial tree. A 21-year-old man with latent and untreated SLE had an attack of acute myocardial infarction. Coronary arteriography showed eccentric stenotic lesion at the proximal segment of the right coronary artery. One week later, in the 2nd coronary arteriography, this stenotic lesion was not able to be recognized. We supposed that the coronary artery occlusion was due to thrombus formation, and was not related to atherosclerosis, arteritis and embolus. He had no coronary risk factors. Laboratory data showed lymphocytopenia, proteinuria, positive antinuclear antibody, and positive LE cell, and the case was diagnosed as SLE. Subsequent investigations showed the presence of antibodies to cardiolipin. It was suggested that anticardiolipin antibody and other thrombogenic factors were the causes of the coronary occlusive thrombosis in this patient with SLE.

Adult↗
PubMed1992

Histological alterations in renal specimens as indicators of prognosis of IgA nephropathy.

A retrospective clinicopathological study of 66 patients with IgA nephropathy was undertaken to determine the prognostic significance of various renal histopathological alterations and clinical parameters. At the latest follow-up, after a period of 60 to 72 months following biopsy, 18 patients had serum creatinine concentration above 1.8 mg/dl. When the entire patients were evaluated as a whole, the extents of interstitial broadening and glomerular sclerosis were correlated significantly with the final status of renal function: proteinuria of more than 1.0 g per day and mildly impaired renal function at the time of biopsy were also associated with unfavourable outcome. However, when the patients with initially normal renal function, i.e. serum creatinine level below 1.2 mg/dl, were evaluated separately, the initial amount of proteinuria, but none of the other parameters, had a prognostic significance in the subsequent course of renal function. These findings suggest that proteinuria of more than 1.0 g per day as an early event often indicates the progression of IgA nephropathy, and lead to a postulation that renal histopathological changes become more significant prognostic indicators in the relatively advanced stage of the disease.

Adult↗
PubMed1991

Primary structure of the alpha-subunit of vacuolar-type Na(+)-ATPase in Enterococcus hirae. Amplification of a 1000-bp fragment by polymerase chain reaction.

A 1000-bp fragment of Enterococcus hirae genomic DNA was amplified by the polymerase chain reaction method, using the oligonucleotide primers designed from amino acid sequences of both amino-terminal and a tryptic fragment of the Na(+)-ATPase alpha-subunit in this organism. DNA sequencing of this product revealed that the amino acid sequence of Na(+)-ATPase alpha-subunit is highly homologous to the corresponding sequences of large (alpha) subunits of vacuolar (archaebacterial) type H(+)-ATPases, supporting our proposal [Kakinuma, Y. and Igarashi, K. (1990) FEBS Lett. 271, 97-101] that the Na(+)-ATPase of this organism belongs to the vacuolar-type ATPase.

Adenosine Triphosphatases↗
PubMed1991

Reversible inactivation of recombinant rat liver guanidinoacetate methyltransferase by glutathione disulfide.

Recombinant rat liver guanidinoacetate methyltransferase is inactivated by glutathione disulfide (GSSG) following pseudo-first-order kinetics. A second-order rate constant of 20.8 M-1 min-1 is obtained at pH 7.5 and 30 degrees C. The inactivation is fully reversed by glutathione (GSH) in a pseudo-first-order fashion with a second-order rate constant of 11.1 M-1 min-1. The rate of inactivation is not affected by S-adenosylmethionine or guanidinoacetate, but complete protection against inactivation is observed in the presence of sinefungin plus guanidinoacetate. At equilibrium in the buffers containing various concentrations of GSH and GSSG, the enzyme shows activities that are dependent on the ratio but not on the total concentration of GSH and GSSG. A hyperbolic relationship is obtained between enzyme activity and [GSH]/[GSSG] ratio. The inactivation by GSSG is associated with the disappearance of approximately 1 mol of sulfhydryl group per mole of enzyme. These results indicate that inactivation of guanidinoacetate methyltransferase by GSSG is the consequence of the formation of a mixed disulfide between a protein thiol and glutathione. The equilibrium constant for the redox reaction, E-SH + GSSG in equilibrium with E-SSG + GSH, obtained from the equilibrium data (1.69) is in good agreement with the value determined as the ratio of second-order rate constants for reactivation and inactivation (1.87). The cysteine residue engaged in the mixed disulfide with glutathione is identified as Cys-15 by peptide analysis after consecutive treatment of the GSSG-inactivated enzyme with N-ethylmaleimide, 2-mercaptoethanol, and [14C]iodoacetate. The GSSG-inactivated enzyme binds S-adenosyl-methionine but not guanidinoacetate in the presence and absence of sinefungin. Native guanidinoacetate methyltransferase binds guanidinoacetate in the presence of sinefungin. The low overall redox equilibrium constant of 1.7-1.9 found for the reaction between guanidinoacetate methyltransferase and GSSG suggests that the activity of the enzyme is not amenable to modulation by the change in intracellular [GSH]/[GSSG] ratio.

Adenosine↗
PubMed1991

Preparation and characterization of the water-soluble heme-binding domain of cytochrome c1 from the Rhodobacter sphaeroides bc1 complex.

The ubiquinol:cytochrome c2 oxidoreductase (bc1 complex) of Rhodobacter sphaeroides consists of four subunits. One of these subunits, cytochrome c1, is the site of interaction with cytochrome c2, a periplasmic protein. In addition, the sequences of the fbcC gene and of the cytochrome c1 subunit that it encodes suggest that the protein should be located on the periplasmic side of the cytoplasmic membrane and that it is anchored to the membrane by a single membrane-spanning alpha-helix located at the carboxyl-terminal end of the polypeptide. Site-directed mutagenesis of the fbcC gene was used to alter the codon for Gln228 to a stop codon. This results in the production of a truncated version of the cytochrome c1 subunit that lacks the membrane anchor at the carboxyl terminus. The bc1 complex fails to assemble properly as a result of this mutation, but the Rb. sphaeroides cells expressing the altered gene contain a water-soluble form of cytochrome c1 in the periplasm. The water-soluble cytochrome c1 was purified and characterized. The amino-terminal sequence is identical with that of the membrane-bound subunit, indicating the signal sequence is properly processed. High pressure liquid chromatography gel filtration chromatography indicates it is monomeric (28 kDa). The heme content and electrochemical properties are similar to those of the intact subunit within the complex. Flash-induced electron transfer kinetics measured using whole cells demonstrated that the water-soluble cytochrome c1 is competent as a reductant for cytochrome c2 within the periplasmic space. These data show that the isolated water-soluble cytochrome c1 retains many of the properties of the membrane-bound subunit of the bc1 complex and, therefore, will be useful for further structural and functional characterization.

Amino Acid Sequence↗
PubMed1991

Molecular cloning of human epidermal transglutaminase cDNA from keratinocytes in culture.

We have isolated a cDNA encoding human epidermal transglutaminase, a key enzyme of terminal differentiation of keratinocytes. A cDNA library from cultured human keratinocytes was screened by a PCR-amplified partial cDNA fragment of the enzyme with oligonucleotide primers based on the homology of the transglutaminase family. The cDNA is 2734 bp coding a protein of 817 amino acids. The several regions including the active site cysteine residue are highly conserved among the transglutaminase family. However, the charged N-terminal domain is unique to the epidermal transglutaminse, suggesting that the region is involved in the function of the enzyme in keratinocytes.

Amino Acid Sequence↗