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H Takakura

Publications and source records attributed to H Takakura.

At least 55 records · Page 3Linked to original sources
PubMed1992

NH2-terminal acetylation of ribosomal proteins of Saccharomyces cerevisiae.

Using a mutant of Saccharomyces cerevisiae defective in the NAT1 gene, that encodes one of the NH2-terminal acetyltransferases, we have identified 14 ribosomal proteins whose electrophoretic mobility at pH 5.0 suggests they carry an additional charge, presumably due to the lack of NH2-terminal acetylation. At least 30 other ribosomal proteins from the mutant are electrophoretically normal. Attempted NH2-terminal analysis of most of the presumed acetylated proteins from wild type cells indicated that all were blocked. NH2-terminal analysis of the same proteins from the nat1 mutant strain yielded unique sequences. Each one carries an NH2-terminal serine. We conclude that these are normally acetylated due to the presence of the NAT1 gene product. It seems surprising that cells whose ribosomes have been altered to this degree grow rather well and synthesize the same spectrum of proteins as do wild type cells (Mullen, J. R., Kayne, P. S., Moerschell, R. P., Tsunasawa, S. Gribskov, M., Sherman, F., and Sternglanz, R. (1989) EMBO J. 8, 2067-2075). Finally, this analysis has provided the first sequence information available for several of the acetylated ribosomal proteins and for one non-acetylated ribosomal protein, which is clearly the product of the MFT1 gene (Garrett, J. M., Singh, K. K., Vonder Haar, R. A., and Emr. S. D. (1991) Mol. Gen. Gen. 225, 483-491).

Acetylation↗
PubMed1992

Deblocking and subsequent microsequence analysis of N alpha-blocked proteins electroblotted onto PVDF membrane.

A method was developed for direct microsequencing of N alpha-acetylated proteins electroblotted onto polyvinylidene difluoride membranes from polyacrylamide gels. N alpha-Acetylated proteins (greater than 32 pmol), including horse heart cytochrome c, five mutants of yeast cytochrome c, and bovine erythrocyte superoxide dismutase, were separated by SDS-PAGE and electroblotted onto polyvinylidene difluoride membranes. The portions of the membrane carrying the bands were cut out and treated with 0.5% polyvinylpyrrolidone in acetic acid solution at 37 degrees C for 30 min. The protein was digested on the membrane with 5-10 micrograms of trypsin at 37 degrees C for 24 h. During tryptic digestion, the resultant peptides were released from the membrane and the N-terminal peptide was efficiently deblocked with 50 mU of acylamino acid-releasing enzyme at 37 degrees C for 12 h. Picomole levels of the deblocked proteins could be sequenced directly by use of a gas-phase protein sequencer.

Acetylation↗
PubMed1991

PMSG profiles in superovulated and anti-PMSG antiserum treated mice and heifers with enzymeimmunoassay.

A sandwich enzymeimmunoassay (EIA) for pregnant mare serum gonadotropin (PMSG) using a microtiter plate was developed. Sensitivity of the assay to PMSG was 15.6 mIU/ml (0.2 ng/well). The PMSG levels in serum were measured with the EIA in superovulated and anti-PMSG rabbit antiserum treated mice and heifers. In mice, the PMSG blood level was measurable in the serum 4-6 days after intraperitoneal injection of 5-30 IU of PMSG. The administration of anti-PMSG antiserum at the same dose level as PMSG caused a rapid decrease in the PMSG blood level, declining to undetectable levels within 17 hours. In heifers, the PMSG level was measurable at 10-11 days after the injection of 2500 or 3000 IU of PMSG. When antiserum was injected 48 hours after the PMSG injection, the clearance rate of PMSG was affected by the route of the administration. The administration of 3000 units of anti-PMSG antiserum intravenously caused a rapid decline and the disappearance of circulating PMSG within 17 hours. When 3000 units of anti-PMSG antiserum was injected intra-muscularly, the PMSG blood level also decreased and became unmeasurable 24 hours after administration; however, it was still detectable for up to 17 hours. These results indicate that the administration of anti-PMSG antiserum at the proper timing and dosage could lead to successful superovulation through the improvement of hormonal conditions.

Animals↗
PubMed1990

Properties of a hemolysin related to the thermostable direct hemolysin produced by a Kanagawa phenomenon negative, clinical isolate of Vibrio parahaemolyticus.

A hemolytic toxin (Vp-TRH) produced by a Kanagawa phenomenon negative, clinical isolate of Vibrio parahaemolyticus was further characterized. The purified Vp-TRH showed various biological activities, such as fluid accumulation in rabbit ileal loops, increase of rabbit skin vascular permeability, and cardiotoxicity on cultured myocardial cells, all of which are essentially similar to the activities found with thermostable direct hemolysin (Vp-TDH), a pathogenic toxin produced by Kanagawa phenomenon positive V. parahaemolyticus. Immunological similarities of Vp-TRH not only to Vp-TDH but also to hemolytic toxins produced by Vibrio hollisae and Vibrio cholerae non-O1, both of which are also enteropathogens closely related to V. parahaemolyticus, were demonstrated. The amino acid composition and sequence of N-terminal amino acids of Vp-TRH were determined. These results suggest that Vp-TRH has biological and immunological characters similar to Vp-TDH, although they are distinct molecules.

Amino Acid Sequence↗
PubMed1990

[Clinical significance of serum cardiac myosin light chain I in patients with muscular dystrophy].

We examined serum cardiac myosin light chain I (LCI), serum creatine kinase (CK) levels and left ventricular function in patients with muscular dystrophy and secondary cardiac involvement. LCI levels were determined by a two-site immunoradiometric assay method in 25 patients with muscular dystrophy and 10 normal subjects. This study included 15 patients with Duchenne muscular dystrophy (DMD), 8 patients with Fukuyama type congenital muscular dystrophy (FCMD) and 2 sisters with non-Fukuyama type congenital muscular dystrophy (nFCMD). We measured the value of left ventricular fractional shortening (FS) using echocardiography. All patients with DMD and FCMD showed moderate or severe skeletal muscle weakness. The mean values of LCI were significantly higher in patients with DMD (11.0 +/- 8.3 ng/ml, p less than 0.01) and in patients with FCMD (1.6 +/- 1.4 ng/ml, p less than 0.05) than in normal subjects (0.3 +/- 0.2 ng/ml). In patients with DMD, LCI level correlated closely with CK level (r = 0.81, p less than 0.01) but not with FS (r = 0.35, n.s.). In patients with FCMD, LCI level correlated significantly with CK level (r = 0.75, p less than 0.05) but not with FS (r = 0.44, n.s.). Close correlation between LCI and CK levels was thought to result from the cross reaction between cardiac LCI and myosin light chains of skeletal muscle in the assay method we used. Two siblings with nFCMD showed mild skeletal muscle weakness. A 22-year-old sister with mild left ventricular dysfunction (FS = 0.41) showed high level of CK (4794/U/L) and mild elevation of LCI (7.3 ngml).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Doppler echocardiographic measurement of flow velocity in cases with a Björk-Shiley aortic prosthesis and diagnosis of prosthetic valve dysfunction].

115 patients with a Björk-Shiley aortic valve prosthesis were studied by means of the ultrasonic Doppler method. The maximum flow velocity at the prosthetic valve was measured by the continuous wave Doppler method, and the velocity at the left ventricular outflow tract was measured by the pulsed wave Doppler method. In addition, flow velocity measured by Doppler method was compared to the valve opening angle obtained by cinefluoroscopy. 1) The maximum velocities at the prosthetic valve in the patients with normally functioning prosthesis were 3.1 +/- 0.4, 2.7 +/- 0.5, 2.2 +/- 0.4, 1.9 +/- 0.3, 1.7 +/- 0.3 m/sec for valve sizes of 21, 23, 25, 27, and 29 mm, respectively. Statistical differences were recognized between the valve size groups. In a case with a thrombosed valve, the maximum velocity was faster than in cases with normally functioning valves and it reached 4.5 m/sec. 2) Flow velocities at the left ventricular outflow tract in patients with normally functioning valves were 0.86 +/- 0.15, 0.86 +/- 0.16, 0.79 +/- 0.14, 0.82 +/- 0.16, 0.75 +/- 0.18 m/sec for valve sizes of 21, 23, 25, 27, 29 mm, respectively. No statistical difference was recognized. In the patients with perivalvular leakage, velocity was faster than in the patients with normally functioning valves. But, in the case with thrombosed valve, it remained within the normal range. 3) No significant correlation was observed between flow velocities and valve opening angles in the cases with normally functioning valves. But, in the cases with malfunctioning valves, flow velocities were faster than normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

[Direct current therapy with chemotherapy for the local control of lung cancer].

Direct current therapy (DC therapy), consisting of the application of electric current directly to the lesion, with chemotherapy using BLM was performed in 4 advanced inoperable lung cancer patients in whom chemotherapy and radiotherapy were not effective or could not be performed. Fluoroscopically two electrodes were inserted percutaneously into the tumor under local anesthesia. The distance between the two electrodes was about 3-4 cm. About 10 volts of direct current for 1 hour (totally over 40 coulombs) was passed between them using a DC treatment processor model 85 (Inter Nova Co., Ltd.), and simultaneously 15-30 mg of BLM was administered intravenously according to the general condition of the patient. The histologic type was adenocarcinoma in 3 cases and there was 1 large cell carcinoma. This treatment was performed once in 3 cases and twice in another. A reduction of tumor size was recognized in 3 cases (2 adenocarcinomas and 1 large cell carcinoma). In another adenocarcinoma case it was not measurable in size because of infiltrative shadow but histologically tumor destruction was recognized within a short period after DC therapy. The complications were mainly slight fever and light pain during the procedure. There was one small amount of hemoptysis and one pneumothorax but it was not necessary to perform special treatment for these complications. DC therapy with chemotherapy is based on our basic experimental experience that some anticancer agents accumulate around the electrodes in lung tissue when direct current is passed. In addition, current itself has cytocidal effects in some cases. Our clinical experience suggested the usefulness of this therapy to treat lung cancer lesions locally.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1989

A mutant hemolysin with lower biological activity produced by a mutant Vibrio parahaemolyticus.

A mutant toxin (m-TDH) of thermostable direct hemolysin (Vp-TDH) of Vibrio parahaemolyticus was isolated from the culture of a strain of this organism mutagenized with N-methyl-N'-nitro-N-nitrosoguanidine. Although the m-TDH had a molecular structure similar to the native Vp-TDH, the m-TDH retained only about 7% residual hemolytic activity of the native toxin. Furthermore, other biological activities of m-TDH, such as lethality in mice and enterotoxicity in rabbit ileal loops, were also weakened. The m-TDH was immunologically indistinguishable from the native Vp-TDH. These results suggest that the m-TDH is only slightly different in structure from the native Vp-TDH. Also, the mutagenized site in m-TDH, which is not immunogenic, seems to be involved in expressing not only hemolytic activity but also lethal and enterotoxic activity.

Amino Acids↗
PubMed1989

[2-dimensional and Doppler echocardiographic follow-up on degenerative changes in Ionescu-Shiley pericardial xenograft].

Using Ionescu-Shiley pericardial xenograft (ISPX), mitral and tricuspid valve replacement was performed on 64 cases during a period of time 1980-1984. On 48 of these 64 cases, ISPX was followed up and observed for its secular change using 2-dimensional echocardiography and ultrasonic Doppler method. The results revealed the following: 1) For ISPX at the mitral position, incidence of obvious cuspal hypertrophy or calcification was 5, 31, and 46% for 3, 5, and 6 years, respectively. 2) Including up to fine changes such as only a slight increase of echo brightness, rate of change detection was as high as 15, 28, 52, and 61% for 2, 3, 5, and 6 years, respectively. 3) Maximum velocity at the left ventricular inflow tract was 1.2-1.5 m/s and remained unchanged so long as ISPX has normally been functioning. Once regurgitation occurred, the flow velocity become greater, and those cases in which it reached 2 m/s needed re-placement. 4) Obvious cuspal hypertrophy showed a tendency to occurring mainly at those cusps which were situated anterior (on the side of outflow tract of left ventricle) regardless of the inserting direction of the prosthetic valve. 5) Five ISPXs at the tricuspid position showed no abnormality. Of 64 cases, 6 (9.4%) showed valvular dysfunction, and even those cases which showed no such dysfunction proved to be subjected to cuspal degeneration at a high rate. For prosthetic valve replacement by ISPX, both frequent examinations by means of echocardiography and Doppler method and careful observation of the course are necessary.

Adult↗
PubMed1988

Clinical, biochemical and ultrastructural study on the pathogenesis of hyperornithinemia-hyperammonemia-homocitrullinuria syndrome.

A 10-year-old boy with the hyperornithinemia, hyperammonemia and homocitrullinuria (HHH) syndrome is described. With dietary restriction of protein intake and supplementary administration of L-ornithine and L-arginine, the high concentration of ammonia decreased and the clinical signs of truncal ataxia and lethargy improved. A deficiency of ornithine transport into liver mitochondria was demonstrated biochemically, and glycogen granules and smooth surface endoplasmic reticulum were increased, but mitochondria showed normal construction ultrastructurally. Cranial computed tomography (CT) showed diffuse white matter low density and cerebellar vermis atrophy. The impairment of ornithine transport and energy production in the central nervous system may be related to the cranial CT findings and neurological signs.

Amino Acid Metabolism, Inborn Errors↗
PubMed1986

The syndrome of the absence of a septum pellucidum with porencephaly.

Two cases of a complex brain malformation including the absence of a septum pellucidum and bilateral porencephaly were reported and compared with Aicardi's cases. The two cases have congenital hemiplegia or double hemiplegia and mental retardation, and one of them has optic atrophy. CT scans revealed the absence of a septum pellucidum and a specific position and shape of the clefts. The syndrome of the absence of a septum pellucidum and porencephaly may represent a specific type of true porencephaly, and the cause must occur before 16 weeks of gestation.

Adolescent↗
PubMed1985

CT and histological findings of diffuse lipomatosis with a hemangioendothelioma: a case report.

A 3 1/2-year-old boy with multiple soft tissue tumors and weakness of the right lower extremity is presented. Swelling of the right lower extremity was noted at 3 weeks, and soft masses at the hip at one year and in the inguinal region at 2 1/2 years of age. Right lower extremity weakness was noted about one year and non-progressive. CT scanning demonstrated characteristic subcutaneous lipomatosis with muscle involvement and a pelvic mass with positive enhancement that infiltrated into the spinal canal. Histological examination revealed diffuse lipomatosis involving muscles in the right hip mass and a lipoma with a hemangioendothelioma in the right inguinal mass. Diffuse lipomatosis combined with a lipoma and a hemangioendothelioma suggests a hamartomatous origin.

Buttocks↗
PubMed1985

A rare case of Aicardi syndrome with severe brain malformation and hepatoblastoma.

A 2-month-old Japanese girl exhibited tonic seizure, agenesis of the corpus callosum, lacunar chorioretinopathy, vertebral anomalies, electroencephalographic abnormalities and a malignant tumor. Autopsy revealed a hepatoblastoma and severe brain malformations consisting of callosal agenesis, arhinencephaly, marked polymicrogyria and optic nerve anomalies. It was thought that the pathogenic factor in this case may exert its effect during the fourth or fifth week of intrauterine life, and then may continue until the beginning of neuronal migration (about 3 months). This is the first reported case of Aicardi syndrome associated with hepatoblastoma, and may provide a link between teratogenicity and oncogenicity.

Abnormalities, Multiple↗