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K Takeshima

Publications and source records attributed to K Takeshima.

At least 37 records · Page 2Linked to original sources
PubMed1997

[Structure of recombinant human serum albumin from Pichia pastoris].

The structure of recombinant human serum albumin derived from Pichia pastoris (rHSA) was analyzed in detail. Complete amino acid analysis was performed by the phenyl isothiocyanate precolumn labeling method. The amino terminal sequence was determined by the Edman degradation. The carboxyl terminal amino acid was determined by digestion with carboxypeptidase, and the carboxyl terminal peptide fragment was analyzed by electrospray mass spectrometry. The peptide fragments of rHSA digested with Lysylendopeptidase, Endoproteinase Glu-C, or Endoproteinase Asp-N were analyzed by electrospray mass spectrometry. The complete amino acid composition, the terminal sequences and the complete amino acid sequence of rHSA agreed with the primary structure deduced from its cDNA. The elution pattern of reduced and carboxymethylated rHSA digested with Lysylendopeptidase and the elution pattern of intact rHSA digested with pepsin were respectively similar to those of plasma-derived human serum albumin (pHSA). The pattern of CD spectrum of rHSA was identical in both shape and magnitude to that of pHSA. 1H-NMR spectra of rHSA and pHSA in deuterium oxide showed the same signal patterns in the observed region (delta 10.5-0.5 ppm). Cross peaks assigned to the alpha proton-beta proton of Asp-1 (delta 4.2/2.8 ppm) and the delta proton-epsilon proton of lysine residues (delta 2.8-3.2/1.4-2.0) showed the same cross peak patterns and chemical shifts in two-dimensional phase sensitive double-quantum filtered 1H-1H correlation spectra of rHSA and pHSA.

Amino Acid Sequence↗
PubMed1996

Activation of two Cynops genes, fork head and sonic hedgehog, in animal cap explants.

We have isolated cDNAs of sonic hedgehog (shh) and fork head from Cynops (Japanese newt) embryo. Their expression was investigated in relation to mesoderm induction by activin and basic fibroblast growth factor (bFGF). Different from these homologs in Xenopus, they are activated not only by activin but also by bFGF in animal cap explants, showing a difference of animal pole cells in responsiveness to bFGF between Cynops and Xenopus. We also investigated the involvement of fork head in shh activation. The expression of shh was activated in animal caps which overexpressed either of two Xenopus fork head homologs, pintallavis/XFD-1 or XFKH-1/XFD-1', indicating that fork head up-regulates the transcription of shh in Cynops embryo.

Activins↗
PubMed1996

[Ligand binding properties and esterase-like activity of recombinant human serum albumin].

The ligand binding properties and esterase-like activity of recombinant human serum albumin (rHSA) expressed by Pichia pastoris were compared with those of plasma derived human albumin (pHSA). The binding of long fatty acid ions was determined by the equilibrium partition method using radiolabeled palmitate. The association constants and the number of binding sites of diazepam, salicylate and warfarin were determined by specific and nonspecific binding models. The high affinity binding of bilirubin was kinetically determined from the oxidation rate of free bililubin in the binding mixture. The binding parameters of these five ligands obtained with rHSA were within the same range observed with pHSA preparations. The kinetic parameters for hydrolytic activity of rHSA toward p-nitrophenyl acetate was also similar to pHSA. These results indicate that rHSA and pHSA have the same functional property.

Bilirubin↗
PubMed1994

[Pharmaceutical dosage form design of copoly (lactic/glycolic acid) microspheres. Mechanism of in vitro release of gentamicin].

The sustained release mechanism of gentamicin (GM) from lactic acid/glycolic acid copolymer (PLGA) microspheres was investigated. The terminal free carboxyl group of polymer was proved to be necessary for GM to be highly incorporated into microspheres by comparing interactions with GM and two types of polymers; free (ionized and non ionized) and the terminal esterified carboxyl group of polymer. The weight-average molecular weights (Mws) of component PLGAs of microspheres with an ionizable carboxyl group used here were approximately 4900 and 10000. The release pattern of GM was tested in phosphate buffered saline. The release rate of GM was dependent on the initial Mw and surface form. The GM release continued for 20 and 30 d from PLGA 4900- and PLGA10000-microspheres, respectively. The changes of total weight of microspheres tended to decrease with time, and the molecular weight distribution of PLGA gradually shifted to lower distribution, indicating a decrease in Mw. The changes and the shifts were dependent on the initial Mws of PLGAs but independent of their surface form. The half-times of wight loss of PLGA 4900- and PLGA10000-microspheres were about 10 and 20 d, respectively. From these results, the release profile of GM from PLGA microspheres was explained by the following three steps, i.e., 1) the release from the surface, 2) the relatively slow release caused by the obstruction of channels followed by the degradation of PLGA, 3) the release accompanied by the erosion of microspheres.

Biotransformation↗
PubMed1994

[A case-control study of risk factors for cerebral hemorrhage in Hirara-City, Okinawa Prefecture].

While the mortality rate of cerebral hemorrhage of Okinawa Prefecture is the lowest in Japan, the presence of a high incidence rate for cerebral hemorrhage has been pointed out in Hirara-city, Okinawa Prefecture. In order to develop an effective counter-measure, a case-control study of risk factors for cerebral hemorrhage was performed. Cases were 62 residents in Hirara city aged 40-69 years who had experienced cerebral hemorrhage between April 1987 through March 1992. From the 62 cases interviewed, responses were obtained from 49 cases. Controls were 147 residents without a history of stroke who were matched to cases individually by sex and age (control/case ratio = 3). From the 49 cases, 28 cases who had participated in residential mass health examinations before experiencing the cerebral hemorrhage, were matched individually sex and age with different randomly selected controls (control/case ratio = 10). From conditional logistic regression analysis of the interview survey data, history of hypertension, interruption of hypertension therapy, family history of stroke, long working hours, overwork and difficulty of taking a day-off each week were strongly related to increased risk of cerebral hemorrhage. Smoking, preference for salty taste and habitual drinking, also, elevated risk slightly. From analysis of the residential mass health examination data, high blood pressure was found to be strongly associated with cerebral hemorrhage, while serum cholesterol was inversely related.

Adult↗
PubMed1993

Diagnosis of right ventricular infarction by overlap images of simultaneous dual emission computed tomography using technetium-99m pyrophosphate and thallium-201.

The validity of dual energy single-photon emission computed tomography (SPECT) with technetium-99m pyrophosphate (Tc-99m PPi) and thallium-201 for the diagnosis of right ventricular (RV) infarction, and the clinical features of RV infarction, were investigated in 190 patients with acute myocardial infarction. Diagnosis of RV infarction was performed by Tc-99m PPi accumulation in the RV myocardium on thallium-201 and Tc-99m PPi over-lay images at the dual SPECT with simultaneous imaging taken 2 to 9 days after the onset of myocardial infarction. Thirty RV infarctions were found among the 190 patients with left ventricular infarction (15.8%): 29 (97%) in association with the inferior and 1 (3%) with the lateral infarction. Tc-99m PPi accumulation was mostly observed in the posterior wall of the right ventricle. A total occlusion or a severe stenosis of the right coronary artery was demonstrated angiographically in 92% of the patients with RV infarction. The prevalence of RV infarctions was significantly lower in patients who achieved successful early reperfusion than in those who did not (26.7 vs 68.4%, respectively, p < 0.01). However, a successful early reperfusion therapy could not significantly decrease the rate of RV involvement in patients without significant collateral flow (p < 0.01). Thus, dual isotope SPECT with Tc-99m PPi and thallium-201 can be used as a reliable method for the diagnosis of RV infarction.

Aged↗
PubMed1992

[Effect of morphological properties on drug release from biodegradable microspheres].

The morphological properties of poly(beta-hydroxybutyric acid) (PHB) or poly(L-lactic acid) microspheres loading flomoxef sodium (FMOX) were investigated with regard to FMOX release. The release profiles of FMOX from the microspheres could be divided into two types, a sustained release type and a burst one. Two representative PHB microspheres, the release profiles of which were quite different from those of FMOX, were compared in detail from a morphological point of view. The shapes of their surfaces and sections were observed by using scanning electron microscopy (SEM), and FMOX distribution was analyzed by using electron probe microanalysis. The crystallinity of polymers was further measured by powder X-ray diffratometry. There was little difference in the FMOX distribution and their microscopic properties such as sphere size, specific surface area, shape of surface and section. In contrast, water penetration into the inside of the microspheres was found to be clearly different by use of cryogenic SEM. A significant difference was also observed in the crystallinity of polymers forming the microspheres. The release of FMOX from the microspheres was affected by the crystallinity of polymers forming the microspheres, and burst phenomena occurred in case the polymer was highly crystallized. It was speculated that the crystallization of polymer induced micro voids in the microspheres which functioned as channels for water penetration.

Biodegradation, Environmental↗
PubMed1989

[An integrated control system for radioisotope facilities].

The authors developed an integrated system for managing the safe use of radioisotope laboratory facilities, users' access to controlled areas, and the control of air-conditioners. This system consisted of a personal computer, an access controller, an eye retinal verifier, magnetic card readers, hand foot cloth monitors, video tape recorders and a fire alarm system. The access controller was set as the central unit to operate the whole system including 13 gates and air-conditioners. Under this program, only registered persons were permitted to enter the laboratories; the exact records on access were easily obtained; and electricity and fuel expenses were largely reduced. We expect that the system would facilitate the safe use of radioisotopes and the utilization of laboratory facilities.

Facility Design and Construction↗
PubMed1988

Monitoring of 131I in milk and rain water in Japan following the reactor accident at Chernobyl and estimates of human thyroidal dose equivalents.

Iodine-131 in milk and in rain water in Nagoya, Japan, (a location 8,000 km from Chernobyl) was monitored between May and July 1986. The 131I concentration in rain water ranged from 43.1 Bq L-1 on 4 May to 15 mBq L-1 on 12 July, and that in milk ranged from 21.8 Bq L-1 on 19 May to 11 mBq L-1 on 14 July. Iodine-131 concentrations in milk were estimated to be 4 to 6 times greater than those in rain water during the first few weeks after the accident. Both concentrations decreased with approximately the same effective half-life of 5.9 +/- 0.3 d for rain water and 5.0 +/- 0.2 d for milk. The 131I concentration in milk sold in markets varied from dairy to dairy and ranged from 0.07 to 0.2 times that in fresh milk. The maximum thyroidal dose equivalents estimated for an adult man and for a baby were far lower than the population annual dose equivalent to the thyroid from natural radiation.

Accidents↗
PubMed1987

[Data processing system of personnel exposure with personal computer].

This paper describes a software package that manages personnel exposure data with a personal computer. The exposure data is automatically transferred to the computer through a floppy disk supplied by film badge service companies. The computer processes data of about 4000 persons who belong to the 11 facilities and prints out the reports on the distribution of personal exposure level. This system made it possible for the radiation protection division to rapidly investigate the actual situation of occupational exposure with less laborious works.

Air Pollution, Radioactive↗
PubMed1984

[Leakage of gaseous 125I during radioiodination using Na125I].

Gaseous 125I was present at 48 +/- 33 and 122 +/- 15 kBq in Na125I vials (74 MBq) purchased from Amersham and New England Nuclear, respectively. Gaseous 125I leaked to the amount of 37 +/- 22 and 130 +/- 67 kBq during radioiodination by the chloramine-T and the enzymatic methods using 18.5 MBq Na125I, respectively. Radioactive wastes from radioiodination using 18.5 MBq Na125I evolved about 5.5 kBq of gaseous 125I in first day of storage.

Air Pollutants↗
PubMed1983

Modification of ribosomal proteins in sea urchin eggs following fertilization.

Analysis of the ribosomal proteins in sea urchin eggs by two-dimensional polyacrylamide gel electrophoresis revealed postfertilization changes in the proteins of both the small and the large subunits. Five egg-ribosomal proteins (S7, S16, S19, L19, L31) appeared to undergo rapid changes to the corresponding embryo-specific proteins. These changes were completed within 30 min after fertilization, and identical electrophoretic patterns were observed among the different developmental stages of embryos. One of the five proteins, S7, showed an increase in the phosphorylated form. The remainder showed qualitative shifts to the corresponding embryo-specific proteins; however, peptide map analyses revealed the existence of common structural units between the corresponding proteins. These modifications were observed in the three species of sea urchin studied (Pseudocentrotus depressus, Hemicentrotus pulcherrimus and Anthocidaris crassispina), except in the case of one protein (L31). Purification of ribosomes by different procedures based on high-salt treatment gave the same results with respect to the egg-specific and embryo-specific proteins.

Animals↗
PubMed1982

Partial purification and comparison of some properties of L-serine sulfhydro-lyase of Saccharomyces cerevisiae.

In order to ascertain the role of L-serine sulfhydro-lyase (L-serine hydro-lyase (adding homocysteine) EC 4.2.1.22) which also catalyzes sulfhydrylation of O-acetyl-L-serine (Yamagata, S. (1981) J. Bacteriol. 147, 688-690), the enzyme was partially purified from a wild-type strain and three cysteine auxotrophs of Saccharomyces cerevisiae, and the molecular and enzymatic properties of these preparations were compared. The results showed no significant difference in properties investigated, indicating that cysteine synthesis is exclusively performed in this organism through sulfhydrylation of O-acetyl-L-serine, catalyzed not by serine sulfhydro-lyase but by O-acetylserine . O-acetylhomoserine sulfhydro-lyase (Yamagata, S., Takeshima, K. and Naiki, N. (1974) J. Biochem. 75, 1221-1229). Insensitivity of the former enzyme to L-methionine also supported this conclusion.

Carbon-Oxygen Lyases↗
PubMed1982

Ribosomal proteins of sea urchin eggs. II. Taxonomical differences.

Ribosomal proteins from unfertilized eggs of three sea urchin species. Pseudocentrotus depressus, Hemicentrotus pulcherrimus, and Anthocidaris crassispina, were analyzed. Species-specific differences were observed in the profiles of large subunit proteins on two-dimensional slab gels, though the number of ribosomal proteins and the molecular weights of their counterparts were the same. The small subunit proteins revealed similarities in the electrophoretic profiles and in the phosphorylation patterns among these three species.

Animals↗
PubMed1982

Ribosomal proteins of sea urchin eggs. I. Characterization of cytoplasmic ribosomal proteins.

Ribosomal proteins from the eggs of sea urchin, Pseudocentrotus depressus, were analyzed by two-dimensional polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate (SDS)-PAGE. Thirty different proteins including three acidic proteins were detected in the small subunit. The large subunit was found to contain at least 43 different proteins, 42 basic and one acidic. The ribosomal proteins from the small subunit have molecular weights ranging from 11,900 to 51,700 (average molecular weight: 25,600). The molecular weights of the large subunit proteins range from 12,700 to 76,300 (average molecular weight: 28,700).

Female↗