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T Kumazaki

Publications and source records attributed to T Kumazaki.

At least 199 records · Page 11Linked to original sources
PubMed1990

Primary structure of ascidian trypsin inhibitors in the hemolymph of a solitary ascidian, Halocynthia roretzi.

The amino acid sequences of trypsin inhibitors I and II from the hemolymph of a solitary ascidian, Halocynthia roretzi, were determined after reduction and S-pyridylethylation. The results indicated that inhibitor I consists of a single polypeptide chain with 55 amino acid residues and four intramolecular disulfide bridges, whereas inhibitor II is composed of two polypeptide chains corresponding to a form derived from inhibitor I by cleavage at the Lys16-Met17 bond. Lys16 may be the reactive-site residue of these inhibitors, because carboxypeptidase B treatment destroys most of the inhibitory activity of inhibitor II but not that of inhibitor I.

Amino Acid Sequence↗
PubMed1990

Disulfide bridge structure of ascidian trypsin inhibitor I: similarity to Kazal-type inhibitors.

The primary structures of ascidian trypsin inhibitors (iso-inhibitors I and II) were reported in the preceding paper (Kumazaki, T. et al. (1990) J. Biochem. 107, 409-413). Both of them have eight half-cystines in a molecule composed of 55 amino acid residues with a sequence showing no extensive homology to other known protease inhibitors. To locate the four disulfide bridges in the molecule, native inhibitor I was digested with thermolysin to yield cystine-containing peptides. The peptides were separated from each other by reversed-phase HPLC. A core peptide still containing six closely located half-cystines (e.g. -Cys-Arg-Cys and -Cys-Cys-) was further digested with Streptomyces griseus trypsin for cleavage of the Arg-Cys bond. On the other hand, the Cys-Cys bond was split by applying manual Edman degradation to the core peptide. Amino acid composition analyses of the resulting cystine peptides allowed us to define the whole disulfide bridge structure in the parent molecule. The topological relation between the disulfide loops and the reactive site suggested that the ascidian trypsin inhibitor may be classified as a member of the Kazal-type inhibitor family.

Acetylation↗
PubMed1990

[Hemangioma of the hypopharynx; a case report and value of MRI].

A case of 23-year-old female with histologically verified hemangioma of the hypopharynx was reported. MRI revealed slight hyper-intense mass on T1-weighted image while it was very high-signal intensity on T2-weighted image. The dynamic MRI showed peak contrast at 80 seconds after administration of Gd-DTPA. In the present paper the value of MRI for diagnosing hemangioma of the hypopharynx is discussed.

Adult↗
PubMed1989

Effect of adrenergic agents on urethral pressure and urethral compliance measurements in dog proximal urethra.

The effects of adrenergic drugs on urethral compliance and urethral closure pressure at the proximal urethra of dogs were investigated using a new probe. The probe, with a balloon at the tip, was equipped with two generating and two detecting electrodes. The probe was inserted into the proximal urethra, and saline was then infused at a constant rate into the balloon with an infusion pump. The pressure and cross-sectional area of the urethra were recorded and a correlation curve of these parameters was drawn. The regression (of the form y = ax + b) was determined from the curve. Urethral compliance and closure pressures were obtained from the values of "a" and "-b/a" respectively, and the maximum cross-sectional area was measured when no further distension of the urethra was obtained. Urethral compliance decreased after the administration of phenylephrine, but increased after the administration of prazosin and labetalol. The urethral closure pressure decreased after the administration of dopamine and haloperidol. There was no change in either urethral compliance or closure pressure after the administration of clonidine, yohimbine, isoproterenol, or propranolol. The results indicate that adrenergic drugs work on urethral compliance, and that the alpha-adrenergic receptor of the proximal urethra is of the alpha-1 type. The changes in the urethral pressure after dopamine administration seems to be a response mediated by dopamine receptors.

Animals↗
PubMed1989

A small nuclear RNA, U5, can transform cells in vitro.

Low-molecular-weight RNA exhibiting transforming potential was identified in chemically induced lymphoma cells by the transformation of mink lung cells after transfection. The RNA was sequenced by the direct chemical method and was shown to be a small nuclear RNA, U5. The transforming potential of the RNA was further studied in quantitative transformation assays using 3Y1, a rat fibroblastic cell line. Transformed foci appeared with a latency of 3 to 4 weeks after transfection. U5-transformed 3Y1 cells frequently carried an amplified c-myc oncogene. In addition, U5 induced chromosome aberrations in transfected cells, indicating that the RNA acts as a clastogen. Transforming and clastogenic potentials were specifically inactivated when U5 was incubated with RNase H in the presence of a complementary oligonucleotide. We discuss a possible mechanism of U5-induced cell transformation.

Animals↗
PubMed1989

[A case of multiple peripheral hepatic artery aneurysms after chemoembolization].

A case of 57-year-old man with multiple peripheral hepatic artery aneurysms is reported. The patient was admitted with liver dysfunction and detected hepatoma in the right lobe. Chemoembolization was performed for the treatment of hepatoma. After 35 days, reangiography revealed multiple peripheral hepatic artery aneurysms in the region of chemoembolization. The etiology of aneurysms were presumably drug induced arteritis.

Aneurysm↗
PubMed1989

[Rupture of right gastric artery aneurysm--a case report and the usefulness of TAE].

A case of a 39-year-old male with ruptured right gastric artery aneurysm was reported. An emergency angiography was carried out followed by transarterial embolization. The TAE was of great value for the control of massive bleeding and for getting out of the urgent surgical operation. In the present report the clinical value of TAE as well as frequency and some diagnostic imagings on this disease was discussed.

Adult↗
PubMed1989

[Transurethral microwave coagulation of bladder cancer in elderly patients].

Since April 1985, 72 patients with bladder cancer have been treated by transurethral microwave coagulation (TUMC). In this procedure, tumors were irradiated with microwave energy of 100 watts for 2-16 minutes. A total of 20 patients were 70 years old or older, including 5 who were more than 80 years old. These 20 patients have been followed for 6 to 32 months with a median follow-up of 14.7 months. After TUMC, tumors completely disappeared endoscopically and histologically in all patients. Four patients had heterotopic recurrences. In all patients, serious complications were not seen during and after TUMC. Our clinical experience revealed that TUMC was the useful therapeutic method for bladder cancer in elderly or poor-risk patients. In this paper, we describe the technique of TUMC and preliminary clinical results.

Aged↗
PubMed1988

Anhydroelastase: enhanced affinity toward product-type ligands revealed by affinity chromatography.

Anhydroelastase was effectively isolated by a single operation of affinity chromatography from a complex mixture produced by phenylmethylsulfonylation and alkaline treatment of porcine pancreatic elastase. The adsorbent used for the chromatography was 6-aminohexanoyl-trialanine, which corresponds to a product of elastase action, immobilized on Sepharose 4B. Successful resolution by the operation indicated that this immobilized ligand possesses the highest affinity for anhydroelastase among various proteins including regenerated elastase in the mixture. Comparative affinity chromatography on immobilized anhydroelastase and on immobilized native elastase further confirmed the stronger interaction of anhydroelastase with the product-type peptides. Immobilized anhydroelastase was also found to be useful in the purification and search for naturally occurring proteinase inhibitors.

Animals↗
PubMed1988

Immobilized anhydrochymotrypsin as a biospecific affinity adsorbent for the peptides produced by chymotryptic hydrolysis.

Anhydrochymotrypsin immobilized on Sepharose specifically adsorbed various peptides containing L-tryptophan, L-tyrosine, or L-phenylalanine residues at their carboxy-termini. These peptides correspond to the specific products of chymotryptic cleavage of polypeptides. A mixture of the chymotryptic peptides once adsorbed on the column could be effectively separated by eluting them with a pH gradient. This adsorbent, on the other hand, showed no substantial affinity toward the substrate-type peptides that contain the aromatic amino acid(s) within the peptide chain, or toward the C-terminal leucine peptides. By taking advantage of this unique property of anhydrochymotrypsin-Sepharose in combination with reversed-phase high-performance liquid chromatography, we have succeeded in separating the C-terminal peptides from chymotryptic digests of reduced and S-carboxymethylated bovine insulin and from tryptic digests from reduced and S-carboxymethylated Streptomyces subtilisin inhibitor.

Adsorption↗
PubMed1988

Effect of water-soluble iodinated contrast media on pressure-flow relationship of red cell suspension.

The effect of radiological contrast media on blood flow through a vascular network was investigated, taking physical and physiological conditions such as osmolality into account. The perfusion of the bullfrog's hind limbs was performed, with a slight modification of the vertical tube method. The effect of contrast media on red cell deformability was studied by perfusion with erythrocyte suspensions in glutaraldehyde-fixed hind limbs. The echinocytic shape change induced by metrizamide and hypertonic iothalamate solutions caused a marked increase in resistance to flow. When the perfusion with erythrocyte suspension was performed using intact hind limbs, the pressure-flow relationship was influenced by contrast media effects on both red cell deformability and the vascular bed. Ioxaglate had less rheologic effect on the pressure-flow relationship than metrizamide or iothalamate. It could be concluded that contrast media should be isotonic, of low viscosity and chemotoxicity, and that ioxaglate was preferable to metrizamide and iothalamate at equal iodine content.

Animals↗
PubMed1988

Nucleotide sequence of the tail tube structural gene of bacteriophage T4.

The nucleotide sequence of gene 19 of bacteriophage T4, the structural gene of the tail tube protein, was determined by both the dideoxy and the Maxam-Gilbert methods. The predicted Mr of tube protein gene product 19 is 18,842. The N-terminal amino acid of the tube protein was determined by Edman degradation, and the C-terminal sequence was confirmed by isolation of the C-terminal tryptic peptide. In the noncoding region between genes 18 and 19, there are two late-T4-promoter consensus sequences, 51 bases apart. The implication of the two late promoter sequences was examined by an S1 nuclease protection experiment. Both serve as weak promoters, but the bulk of the transcripts arise from further upstream of the two promoters.

Amino Acid Sequence↗
PubMed1988

Combination therapy with microwave coagulation and intracavitary irradiation for bladder cancer. Technique and preliminary clinical results.

Twenty-five patients with transitional cell carcinoma of the bladder have been treated with combined therapy consisting of microwave regional coagulation and intracavitary irradiation. A remote-controlled after-loading system was utilized for the radiation therapy. The follow-up period ranged from 6 to 19 months with an average of 11.4 months. Tumor stages were Tis (n = 2), Ta or T1 (n = 17), T2 (n = 2), T3 (n = 3) and T4 (n = 1), and grades were G1 (n = 10), G2 (n = 11) and G3 (n = 4). In 23 patients (92%), there was no endoscopic or histologic evidence of tumor after the initial treatment. Heterotopic recurrences were found after 2 or 3 months in 3 patients who received microwave regional coagulation or intracavitary regional irradiation. Additional intracavitary whole bladder mucosal irradiation was performed for 10 patients with multiple tumors and frequent recurrent tumors. Nine patients had no recurrence (average follow-up 11 months). Our preliminary findings indicate that combination therapy of microwave coagulation and intracavitary irradiation is a useful treatment for bladder cancer.

Brachytherapy↗
PubMed1988

Microwave coagulation therapy for urinary bladder tumors.

A new device has been developed for microwave coagulation of urinary bladder tumors. Twenty-one patients with urinary bladder tumors were treated by irradiation with microwave energy of 2,450 MHz. Results were obtained as follows: (1) microwave coagulation was performed in 21 patients with transitional cell carcinoma of the urinary bladder. Excluding 4 patients who subsequently received radical cystectomy, 17 patients showed a complete response, although 2 patients subsequently developed recurrences in different parts of the bladder within the following several months. Histological examination of the excised specimen revealed complete eradication of the tumor in 2 patients. In the remaining 2 patients with high-stage tumor (T4), viable tumor cells were noted in the urethra or vaginal wall. (2) Although neither technical difficulties nor severe complications were encountered, transient urinary frequency and calcification of the bladder wall were noted. The results of this study indicate that microwave coagulation may be used in the treatment of both superficial and invasive tumors.

Aged↗