- My name is Masaharu Takeda, Ph.D. I have studied biochemisty, molecular biology for a sea-snake-venom erabutoxin a... moreMy name is Masaharu Takeda, Ph.D. I have studied biochemisty, molecular biology for a sea-snake-venom erabutoxin and a mitochondrial F1F0-ATPase complex in the yeast Saccharomyces cerevisiae, after emeritus, 2012, I am interested in the genome and the biological information of the living cells.edit
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Nowadays, human senses of vision and hearing receive many stimulations. In particular, VDT work is commonly performed by people of all ages. Therefore, in order to regulate working hours we need to measure the fatigue due to VDT work. The... more
Nowadays, human senses of vision and hearing receive many stimulations. In particular, VDT work is commonly performed by people of all ages. Therefore, in order to regulate working hours we need to measure the fatigue due to VDT work. The current measuring system depends on the flicker value (CFF). This report describes a new measuring system which depends on the measurement of the fluctuation in the minimum audible pressure (MAP) while using the increase of threshold value as an index of fatigue, and the results of the related experiment. In Test 1, the test sound was set at the pure sound of 1,000 Hz. In Test 2, an ordinary hearing acuity inspection room was used, using the method of limit measurement and headphones (Telephonics, TDH39, MX41/AR). As a result, it was verified that the most suitable rate of increasing and decreasing audible pressure was by 2 dB or 1 dB. It was proved from these tests that the minimum audible pressure could be used satisfactorily as a practical index for absolute measurement of hearing sense fatigue.
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ABSTRACT
ABSTRACT
Mitochondria prepared from the yeast nuclear pet mutant N9-84 lack a detectable F1-ATPase activity. Genetic complementation of this mutant with a pool of yeast genomic DNA in the yeast Escherichia coli shuttle vector YEp13 restored its... more
Mitochondria prepared from the yeast nuclear pet mutant N9-84 lack a detectable F1-ATPase activity. Genetic complementation of this mutant with a pool of yeast genomic DNA in the yeast Escherichia coli shuttle vector YEp13 restored its growth on a nonfermentable carbon source. Mitochondria prepared from the transformed host contained an 8-fold higher than normal level of the F1 alpha-subunit and restored ATPase activity to 50% that of the wild-type strain. Deletion and nucleotide sequence analysis of the complementing DNA on the plasmid revealed a coding sequence designated ATP1 for a protein of 544 amino acids which exhibits 60 and 54% direct protein sequence homology with the proton-translocating ATPase alpha-subunits from tobacco chloroplast and E. coli, respectively. In vitro expression and mitochondrial import experiments using this ATP1 sequence showed that additional amino-terminal sequences not present in the comparable plant and bacterial subunits function as transient sequences for import.
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Research Interests: Kidney diseases, Vitamin A, Humans, Female, Male, and 5 moreAged, Middle Aged, Adult, Chronic Kidney Failure, and Renal Dialysis
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We present here the observation of the Talbot effect in digital holography (DH). A self-imaging phenomena is observed by reconstructing the amplitude of the object wavefield by using different distances and different illumination... more
We present here the observation of the Talbot effect in digital holography (DH). A self-imaging phenomena is observed by reconstructing the amplitude of the object wavefield by using different distances and different illumination wavelengths. The numerical reconstruction allows to determine the complex field amplitude at different wavelengths while maintaining constant the reconstruction distance. We investigate on the possibility to build
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The boron nitride (BN) coating was applied on Hi-Nicalon by chemical vapor deposition (CVD) from boron trichloride, ammonia and hydrogen gases mixture. The BN coating contained hexagonal BN and 10 at. % carbon. The 3-D woven BN coated... more
The boron nitride (BN) coating was applied on Hi-Nicalon by chemical vapor deposition (CVD) from boron trichloride, ammonia and hydrogen gases mixture. The BN coating contained hexagonal BN and 10 at. % carbon. The 3-D woven BN coated Hi-Nicalon fiber-reinforced SiC composite was fabricated by CVI+PIP combined process with different interphase thickness. Tensile strength of the composites at room temperature is 368 MPa for 0.35 μm BN and 390 MPa for 0.55 μm BN interphase thickness. 100-hour creep rupture stress of the composites at 900°C in air is 135 MPa, showing significant advantage of Hi-Nicalon fiber reinforced enhanced SiC composite (72 MPa).
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ABSTRACT
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The 36K protein attached at the 5' end of the linear DNA plasmid pGKL2 from the yeast Kluyveromyces lactis was first purified and characterized. The terminal protein was purified from cells (1 kg wet weight) by ammonium sulphate... more
The 36K protein attached at the 5' end of the linear DNA plasmid pGKL2 from the yeast Kluyveromyces lactis was first purified and characterized. The terminal protein was purified from cells (1 kg wet weight) by ammonium sulphate precipitation and two rounds of centrifugation to equilibrium in CsCl gradients. The pGKL2 was present only in the post-microsomal supernatant. Approximately 10 mg of the purified pGKL2 was recovered and digested with DNase I. The terminal protein (final ca. 0 center dot 8 mg) was homogeneous by electrophoresis and we determined the N-terminal amino acid sequence up to ten residues, showing that it existed in the cryptic N-terminal domain of pGKL2-ORF2 (DNA polymerase) sequence.
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Chromosome fragmentation, ATP1 disruption, and Southern blot analyses of total DNAs and prime clones of chromosome II showed that three identical ATP1s are present, directing from the telomere to the centromere on the 35-55 kb far from... more
Chromosome fragmentation, ATP1 disruption, and Southern blot analyses of total DNAs and prime clones of chromosome II showed that three identical ATP1s are present, directing from the telomere to the centromere on the 35-55 kb far from the left telomere sequence of chromosome II. That is, the coding and 5'-, 3'-non-coding regions of ATP1 are repeated 3 times at approximately 7 kb intervals. These three ATP1s are expressed, and one and two ATP1s-disrupted strains, respectively, showed ca.70 and 40% decreases in their ATPase activities and alpha subunit contents, compared to those of the wild type, DC-5 or W303-1A strain, but could grow on glycerol.
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1. Addition of glucose induced an inactivation of mitochondrial enzymes in the yeast Saccharomyces cerevisiae containing normal mitochondrial particles. 2. The glucose-induced inactivation of mitochondrial enzymes was inhibited by the... more
1. Addition of glucose induced an inactivation of mitochondrial enzymes in the yeast Saccharomyces cerevisiae containing normal mitochondrial particles. 2. The glucose-induced inactivation of mitochondrial enzymes was inhibited by the presence of cycloheximide. 3. Pepstatin also inhibited the inactivation, but phenylmethanesulphonyl fluoride accelerated the inactivation. 4. The specific activities of fructose 1,6-bisphosphatase and cytoplasmic malate dehydrogenase were decreased on the exposure to glucose, as well as those of the mitochondrial enzymes. However, the glucose-induced inactivation of cytoplasmic enzymes was not inhibited by the presence of pepstatin. 5. The specific activities of hexokinase and phosphofructokinase, which are cytoplasmic enzymes were increased by the addition of glucose, and this effect was not affected by pepstatin. 6. Addition of glucose resulted in an increase in the synthesis of proteins of the mitochondria and the cytosol, and simultaneously in degr...
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The yeast nuclear gene ATP2 encodes a F1-ATPase beta-subunit protein of 509 amino acids with a predicted mass of 54,575 daltons. In contrast to the ATPase beta-subunit proteins determined previously from Escherichia coli and various plant... more
The yeast nuclear gene ATP2 encodes a F1-ATPase beta-subunit protein of 509 amino acids with a predicted mass of 54,575 daltons. In contrast to the ATPase beta-subunit proteins determined previously from Escherichia coli and various plant sources, the yeast mitochondrial precursor peptide contains a unique cysteine residue within its immediate amino terminus. Expression of an in-frame deletion in ATP2 between residues 28 and 34 to eliminate this single cysteine residue located near the processing site of the matrix protease does not prevent the in vivo delivery of the subunit to mitochondria or its assembly into a functional ATPase complex. Thus, the import F1 beta-subunit into mitochondria does not require a covalent modification of the type utilized for the secretion of the major lipoprotein from E. coli. In addition, analysis of the level of the major F1-ATPase subunits in mitochondria prepared from an atp2- disruption mutant demonstrates that the in vivo import of these catalyti...
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ABSTRACT The ATP2 gene of Saccharomyces cerevisiae codes for the cytoplasmically synthesized beta-subunit protein of the mitochondrial F1-ATPase. To define the amino acid sequence determinants necessary for the in vivo targeting and... more
ABSTRACT The ATP2 gene of Saccharomyces cerevisiae codes for the cytoplasmically synthesized beta-subunit protein of the mitochondrial F1-ATPase. To define the amino acid sequence determinants necessary for the in vivo targeting and import of this protein into mitochondria, we have constructed gene fusions between the ATP2 gene and either the Escherichia coli lacZ gene or the S. cerevisiae SUC2 gene (which codes for invertase). The ATP2-lacZ and ATP2-SUC2 gene fusions code for hybrid proteins that are efficiently targeted to yeast mitochondria in vivo. The mitochondrially associated hybrid proteins fractionate with the inner mitochondrial membrane and are resistant to proteinase digestion in the isolated organelle. Results obtained with the gene fusions and with targeting-defective ATP2 deletion mutants provide evidence that the amino-terminal 27 amino acids of the beta-subunit protein precursor are sufficient to direct both specific sorting of this protein to yeast mitochondria and its import into the organelle. Also, we have observed that certain of the mitochondrially associated Atp2-LacZ and Atp2-Suc2 hybrid proteins confer a novel respiration-defective phenotype to yeast cells.
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The 36K protein attached at the 5' end of the linear DNA plasmid pGKL2 from the yeast Kluyveromyces lactis was first purified and characterized. The terminal protein was purified from cells (1 kg wet weight) by ammonium sulphate... more
The 36K protein attached at the 5' end of the linear DNA plasmid pGKL2 from the yeast Kluyveromyces lactis was first purified and characterized. The terminal protein was purified from cells (1 kg wet weight) by ammonium sulphate precipitation and two rounds of centrifugation to equilibrium in CsCl gradients. The pGKL2 was present only in the post-microsomal supernatant. Approximately 10 mg of the purified pGKL2 was recovered and digested with DNase I. The terminal protein (final ca. 0 center dot 8 mg) was homogeneous by electrophoresis and we determined the N-terminal amino acid sequence up to ten residues, showing that it existed in the cryptic N-terminal domain of pGKL2-ORF2 (DNA polymerase) sequence.
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The A TP2 gene of Saccharomyces cerevis- iae codes for the cytoplasmically synthesized 13-sub- unit protein of the mitochondrial F1-ATPase. To de- fine the amino acid sequence determinants necessary for the in vivo targeting and import of... more
The A TP2 gene of Saccharomyces cerevis- iae codes for the cytoplasmically synthesized 13-sub- unit protein of the mitochondrial F1-ATPase. To de- fine the amino acid sequence determinants necessary for the in vivo targeting and import of this protein into mitochondria, we have constructed gene fusions between the A TP2 gene and either the Escherichia coli lacZ gene or the
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ABSTRACT Southern blot analysis showed that ATP1 and ATP2 map on chromosomes II and X, respectively. Physical mapping of ATP1 and ATP2 by chromosome fragmentation showed that ATP1 is at the left end of chromosome II and ATP2 is at the... more
ABSTRACT Southern blot analysis showed that ATP1 and ATP2 map on chromosomes II and X, respectively. Physical mapping of ATP1 and ATP2 by chromosome fragmentation showed that ATP1 is at the left end of chromosome II and ATP2 is at the right end of chromosome X. Both are located close to telomere sequences of each chromosome; ATP1 and ATP2 being approximately 30 kb and 85 kb from the respective telomeres.
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Little is known about the role of the M cells of human nasopharyngeal lymphoid tissue in the sampling of viruses that cause respiratory infections. To clarify whether M cells could function as a gateway for influenza virus into human... more
Little is known about the role of the M cells of human nasopharyngeal lymphoid tissue in the sampling of viruses that cause respiratory infections. To clarify whether M cells could function as a gateway for influenza virus into human nasopharyngeal lymphoid tissue, excised adenoid tissue was incubated in media containing influenza A virus for 30, 60, and 90 min, respectively. Transmission electron microscopic observation revealed that many influenza viruses adhered to M cell surfaces and were taken up into the cytoplasmic vesicles of M cells after 30 min incubation; the viruses had been transported into enfolded lymphoid cells after 60 min incubation. By staining M cells with Sambucus nigra lectin, which specifically recognizes the NeuAcalpha2,6 Gal linkage of sialoprotein, it was also found that abundant receptors for the human influenza virus are present on the M cell surface. Our findings indicated that M cells of human nasopharyngeal tonsils function as a major port for influenza A virus entry and that the virus could be efficiently transferred to enfolded macrophages and lymphoid cells by M cells. The transport of influenza viruses to lymphoid cells by M cells may promote antigen delivery to the immune system, and these findings may be important for systemic delivery of those influenza viruses that have the capacity to productively infect cells outside of the respiratory tract.
Research Interests: Electron Microscopy, Macrophages, Adolescent, Influenza virus, Sampling, and 15 moreHumans, Child, Virus, Female, Male, Clinical Sciences, Immune system, Respiratory Tract Infections, influenza A virus, Transmission Electron Microscope, Lymphocytes, Cell Surface Markers, Cytoplasm, Lymphoid Tissue, and Child preschool
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ABSTRACT
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ABSTRACT
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The dispersion term in the intermolecular potential calculated from the Rayleigh-Schrödinger perturbation theory exhibits the similar angle dependence as assumed by Maier-Saupe for the model system of MBBA.
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The patient, an 18-yr-old male (admission ht 153 cm, wt 30 kg), had been suffering from growth arrest and intermittent abdominal pain since he was 13 yr old, which was left untreated. Examinations on admission disclosed almost normal... more
The patient, an 18-yr-old male (admission ht 153 cm, wt 30 kg), had been suffering from growth arrest and intermittent abdominal pain since he was 13 yr old, which was left untreated. Examinations on admission disclosed almost normal pituitary function, while levels of testosterone and somatomedin C were low. Roentgenological examination revealed extensive skip-stenotic lesions and longitudinal ulcers in the ileum, diagnostic of Crohn's disease. Therapy involving high-caloric parenteral and enteral alimentation resulted in a marked increase in both ht and wt, and improvement in roentgenological and colonoscopical findings. The interrelation between Crohn's disease and malnutrition with reference to some reports in the literature is discussed.
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Research Interests: Information Systems, Genetics, Genomics, Cell line, Humans, and 19 moreMice, Animals, Polymerase Chain Reaction, Genetic Map, Y chromosome, Molecular cloning, Genome Organization, Hybrid Solar Cells, Chickens, Amino Acid Profile, Base Sequence, Chemokines, Structure activity Relationship, Recombinant Proteins, Nucleotides, Somatic Cells, Retinoic Acid Receptor, DNA sequence, and Molecular Sequence Data
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A case of depressed early gastric cancer with nodular gastritis is described. A 47-year-old Japanese man was referred to our hospital and admitted for surgical treatment of gastric cancer. Barium upper gastrointestinal study and endoscopy... more
A case of depressed early gastric cancer with nodular gastritis is described. A 47-year-old Japanese man was referred to our hospital and admitted for surgical treatment of gastric cancer. Barium upper gastrointestinal study and endoscopy examination showed a 4.5 × 3.0 cm ...