Biomedical subjects

T Koide

Publications and source records attributed to T Koide.

At least 55 records · Page 3Linked to original sources

PubMed2000

[Tocopherol Acetate Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of tocopherol acetate was examined for the preparation of the "Tocopherol Acetate Reference Standard (Control 001)". Analytical data obtained were: IR spectrum, same as that of the Tocopherol Acetate Reference Standard (Control 974); specific absorbance, E/cm% (284 nm) = 43.7; thin-layer chromatography, no impurities were detected until 50 micrograms of the loaded raw material; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 0.6%; assay by HPLC, 101.7%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 001).

Chromatography, High Pressure Liquid↗

PubMed2000

[Tocopherol Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of tocopherol was tested for the preparation of "Tocopherol Reference Standard (Control 991)". Analytical data obtained were: IR spectrum, same as the Tocopherol Reference Standard (Control 941); specific absorbance, E/cm% (292 nm) = 72.9; thin-layer chromatography, no impurities were detected until 50.0 micrograms; high-performance liquid chromatography (HPLC), trace amounts of five impurities were detected and the total amount was estimated to be less than 1.4%; assay by HPLC, 99.9%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Standard (Control 991).

Chromatography, High Pressure Liquid↗

PubMed2000

[Prednisolone Sodium Phosphate Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material for prednisolone sodium phosphate was examined for the preparation of the "Prednisolone Sodium Phosphate Reference Standard (Control 001)". The analytical data obtained were: pH, 7.9; optical rotation, [alpha]D20 = +98.0 degrees; UV spectrum, lambda max of 248 nm and specific absorbance in ethanol at 248 nm = 306.7; IR spectrum, same as that of the Prednisolone Sodium Phosphate Reference Standard (Control 892); thin-layer chromatography, five impurities were detected at 200 micrograms; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 3.7%; residual solvent, 0.0% (ethanol) and 0.0% (hexane); loss on drying, 2.7%. Based on the above results, the raw material was authorized as the Prednisolone Sodium Phosphate Reference Standard (Control 001) of the National Institute of Health Sciences.

Chromatography, High Pressure Liquid↗

PubMed2000

[Estradiol Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of tocopherol was tested for the preparation of "Estradiol Reference Standard (Control 991)". Analytical data obtained were: melting point, 178.5 degrees C: UV spectrum, lambda max of 281 nm and specific absorbance in ethanol at lambda max = 77.7; IR spectrum, same as that of the Estradiol Reference Standard (Control 964); optical rotation, [alpha]D20 = +79.5 degrees; thin-layer chromatography, one impurity was detected; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 0.6%; loss on drying, 3.3%; assay, 100.2% by UV spectrophotometry and 99.9% by HPLC. Based on the above results, the raw material was authorized as the Estradiol Reference Standard (Control 001) of the National Institute of Health Sciences.

Chromatography, High Pressure Liquid↗

PubMed1999

Substrate recognition of collagen-specific molecular chaperone HSP47. Structural requirements and binding regulation.

Prior to secretion, procollagen molecules are correctly folded to triple helices in the endoplasmic reticulum (ER). HSP47 specifically associates with procollagen in the ER during its folding and/or modification processes and is thought to function as a collagen-specific molecular chaperone (Nagata, K. (1996) Trends Biochem. Sci. 21, 23-26). However, structural requirements for substrate recognition and regulation of the binding have not yet been elucidated. Here, we show that a typical collagen model sequence, (Pro-Pro-Gly)(n), possesses sufficient structural information required for recognition by HSP47. A structure-activity relationship study using synthetic analogs of (Pro-Pro-Gly)(n) has revealed the requirements in both chain length and primary structure for the interaction. The substrate recognition of HSP47 has also been shown to be similar but distinct from that of prolyl 4-hydroxylase, an ER resident enzyme. Further, it has shown that the interaction of HSP47 with the substrate peptides is abolished by prolyl 4-hydroxylation of the second Pro residues in Pro-Pro-Gly triplets and that the fully prolyl 4-hydroxylated peptide, (Pro-Hyp-Gly)(n), does not interact with HSP47. We thus have proposed a model in which HSP47 dissociates from procollagen during the process of prolyl 4-hydroxylation in the ER.

Amino Acid Sequence↗

PubMed1999

Role of factor VIII C2 domain in factor VIII binding to factor Xa.

Factor VIII (FVIII) is activated by proteolytic cleavages with thrombin and factor Xa (FXa) in the intrinsic blood coagulation pathway. The anti-C2 monoclonal antibody ESH8, which recognizes residues 2248-2285 and does not inhibit FVIII binding to von Willebrand factor or phospholipid, inhibited FVIII activation by FXa in a clotting assay. Furthermore, analysis by SDS-polyacrylamide gel electrophoresis showed that ESH8 inhibited FXa cleavage in the presence or absence of phospholipid. The light chain (LCh) fragments (both 80 and 72 kDa) and the recombinant C2 domain dose-dependently bound to immobilized anhydro-FXa, a catalytically inactive derivative of FXa in which dehydroalanine replaces the active-site serine. The affinity (K(d)) values for the 80- and 72-kDa LCh fragments and the C2 domain were 55, 51, and 560 nM, respectively. The heavy chain of FVIII did not bind to anhydro-FXa. Similarly, competitive assays using overlapping synthetic peptides corresponding to ESH8 epitopes (residues 2248-2285) demonstrated that a peptide designated EP-2 (residues 2253-2270; TSMYVKEFLISSSQDGHQ) inhibited the binding of the C2 domain or the 72-kDa LCh to anhydro-FXa by more than 95 and 84%, respectively. Our results provide the first evidence for a direct role of the C2 domain in the association between FVIII and FXa.

Amino Acid Sequence↗

PubMed1999

Factor XII Tenri, a novel cross-reacting material negative factor XII deficiency, occurs through a proteasome-mediated degradation.

A homozygous cross-reacting material negative factor XII-deficient patient with 3% antigen and activity levels of factor XII was screened for the identification of a mutation at the genomic level. Low-ionic strength single-stranded conformation polymorphism (SSCP) analysis and sequence analysis showed that the proband's gene for factor XII had an A-->G substitution at nucleotide position 7832 in exon 3, resulting in a Tyr34 to Cys substitution in the NH2-terminal type II domain of factor XII. We designated this mutation as factor XII Tenri. Mutagenic polymerase chain reaction (PCR), followed by KpnI digestion, showed a homozygous mutation in the proband's gene and heterozygous mutations in his parents and sister. Immunoprecipitation and Western blot analyses of plasma samples from the factor XII Tenri family indicated that the proband had a trace amount of variant factor XII with an apparent molecular mass of 115 kD, which was converted to the normal 80-kD form after reduction, suggesting that factor XII Tenri was secreted as a disulfide-linked heterodimer with a approximately 35-kD protein, which we identified as alpha1-microglobulin by immunoblotting. Pulse-chase experiments using baby hamster kidney (BHK) cells showed that Tenri-type factor XII was extensively degraded intracellularly, but the addition of cystine resulted in increased secretion of the mutant. Using membrane-permeable inhibitors, we observed that the degradation occurred in the pre-Golgi, nonlysosomal compartment and a proteasome appeared to play a major role in this process. On the basis of these in vitro results, we speculate that the majority of the factor XII Tenri is degraded intracellularly through a quality control mechanism in the endoplasmic reticulum (ER), and a small amount of factor XII Tenri that formed a disulfide-linked heterodimer with alpha1-microglobulin is secreted into the blood stream.

Adult↗

PubMed1999

The genomic organization of type I keratin genes in mice.

We isolated two new keratin cDNAs by screening a cDNA library constructed from poly(A)+ RNA of the dorsal and abdominal skin of C57BL/10J mice with a probe of human KRT14. Due to its high sequence homology to human keratin 17 cDNA, one full-length cDNA is most likely to be mouse keratin 17 (Krt1-17) cDNA. The other is the putative full-length cDNA of a novel type I keratin gene, designated Krt1-c29. These two keratin genes were mapped to the distal portion of Chromosome 11, where the mouse keratin gene complex-1 (Krt1) is localized. To elucidate the genomic organization of Krt1 in mice, we carried out genetic and physical analyses of Krt1. A large-scale linkage analysis using intersubspecific backcrosses suggested that there are two major clusters in Krt1, one containing Krt1-c29, Krt1-10, and Krt1-12 and the other containing Krt1-14, -15, -17, and -19. Truncation experiments with two yeast artificial chromosome clones containing the two clusters above have revealed that the gene order of Krt1 is centromere-Krt1-c29-Krt1-10-Krt1-12-Krt1-13-K rt1-15-Krt1-19-Krt1-14-K rt1-17-telomere. Finally, we analyzed sequence divergence between the genes belonging to the Krt1 complex. The results clearly indicated that genes are classified into two major groups with respect to phylogenetic relationship. Each group consists of the respective gene cluster demonstrated by genetic and physical analyses in this study, suggesting that the physical organization of the Krt1 complex reflects the evolutionary process of gene duplication of this complex.

Amino Acid Sequence↗

PubMed1999

Possible causes for the low prevalence of pediatric urolithiasis.

OBJECTIVES: To determine why the incidence of pediatric urolithiasis is less than that of adult urolithiasis, we investigated the difference in inhibition of calcium oxalate (CaOX) crystallization between pediatric and adult urinary macromolecules (UMMs). METHODS: Urinary parameters in relation to urolithiasis, the inhibition of CaOX crystallization of original urine and urine from which UMMs (greater than 3 kDa) had been removed, and the inhibition of CaOX crystal growth and aggregation of UMMs alone were measured. These inhibitory activities were compared between children and adults. RESULTS: In the original urine, the inhibition of CaOX crystallization was significantly stronger for children than for adults, but was the same in urine from which the UMMs had been removed. The inhibition of CaOX crystal growth by UMMs alone showed no significant differences between children and adults; their inhibition of CaOX crystal aggregation was significantly stronger for children than for adults. Much more glycosaminoglycan (GAG) was included in pediatric UMMs than in adult UMMs, although there was no difference in UMM concentration between urine from children and urine from adults. CONCLUSIONS: The lower incidence of CaOX lithiasis in children may be attributed, among other factors, to the stronger inhibition of CaOX crystal aggregation by pediatric UMMs, which in turn might be affected by the higher concentration of GAGs in children's urine.

Adolescent↗

PubMed1999

Retinoic acid induces down-regulation of Wnt-3a, apoptosis and diversion of tail bud cells to a neural fate in the mouse embryo.

The tail bud comprises the caudal extremity of the vertebrate embryo, containing a pool of pluripotent mesenchymal stem cells that gives rise to almost all the tissues of the sacro-caudal region. Treatment of pregnant mice with 100 mg/kg all-trans retinoic acid at 9.5 days post coitum induces severe truncation of the body axis, providing a model system for studying the mechanisms underlying development of caudal agenesis. In the present study, we find that retinoic acid treatment causes extensive apoptosis of tail bud cells 24 h after treatment. Once the apoptotic cells have been removed, the remaining mesenchymal cells differentiate into an extensive network of ectopic tubules, radially arranged around the notochord. These tubules express Pax-3 and Pax-6 in a regionally-restricted pattern that closely resembles expression in the definitive neural tube. Neurofilament-positive neurons subsequently grow out from the ectopic tubules. Thus, the tail bud cells remaining after retinoic acid-induced apoptosis appear to adopt a neural fate. Wnt-3a, a gene that has been shown to be essential for tail bud formation, is specifically down-regulated in the tail bud of retinoic acid-treated embryos, as early as 2 h after retinoic acid treatment and Wnt-3a transcripts become undetectable by 10 h. In contrast, Wnt-5a and RAR-gamma are still detectable in the tail bud at that time. Extensive cell death also occurs in the tail bud of embryos homozygous for the vestigial tail mutation, in which there is a marked reduction in Wnt-3a expression. These embryos go on to develop multiple neural tubes in their truncated caudal region. These results suggest that retinoic acid induces down-regulation of Wnt-3a which may play an important role in the pathogenesis of axial truncation, involving induction of widespread apoptosis, followed by an alteration of tail bud cell fate to form multiple ectopic neural tubes.

Animals↗

PubMed1999

The inhibitory properties and primary structure of a novel serine proteinase inhibitor from the fruiting body of the basidiomycete, Lentinus edodes.

A novel proteinase inhibitor, Lentinus proteinase inhibitor, has been purified from the fruiting bodies of the edible mushroom, Lentinus edodes, by buffer extraction and affinity chromatography on immobilized anhydrotrypsin. The protein simultaneously inhibits bovine beta-trypsin and alpha-chymotrypsin at independent sites, with apparent dissociation constants of 3.5 x 10(-10) M and 4 x 10(-8) M, respectively. The purified protein is eluted as two well-separated peaks on reversed-phase HPLC, one of which is inhibitory-active and the other inactive, and they are interconvertible under folding/unfolding conditions. Among the mammalian and microbial serine proteinases examined, including human enzymes of blood coagulation and fibrinolysis, activated factor XI was inhibited by the Lentinus proteinase inhibitor. Chemical modification studies suggest involvement of one or more arginine residues in the inhibition of trypsin. The complete primary structure composed of 142 amino acids with an acetylated N-terminus was determined by protein analysis. The theoretical molecular mass (15999.2) from the sequence is close to the experimental value of 15999.61 +/- 0.61 determined by mass spectrometry. Although there are no apparently homologous proteinase inhibitors in the protein database, there is a rather striking similarity to the propeptide segment of a microbial serine proteinase, as well as to the N-terminal region of the mature enzyme.

Amino Acid Sequence↗

PubMed1999

Proteoglycan core protein in human urine and its possible role on calcium oxalate urolithiasis.

BACKGROUND: There are only a few papers reporting on the role of proteoglycan core protein in calcium oxalate stone formation. The present study was carried out to investigate the role of core protein of proteoglycan in human urine on calcium oxalate (CaOx) crystallization. METHODS: Proteoglycans were collected from whole human urine. The covalently bound glycosaminoglycans (GAG) of proteoglycans were then digested by GAG lyase. The inhibitory activity on CaOx crystal growth in vitro was measured before and after enzyme digestion of proteoglycans. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the core protein of proteoglycans and the analysis of amino acid sequence were performed. RESULTS: The core protein showed significant inhibitory activity on CaOx crystal growth, which scarcely changed when compared with that of proteoglycans before enzyme digestion. The SDS-PAGE revealed that the core protein was a single unit with a molecular weight of 26 kDa and amino acid sequencing demonstrated high homology to interalpha-trypsin inhibitor (ITI) light chain (bikunin) with Kunitz inhibitor domain as a core protein. CONCLUSIONS: The results suggested that human urine contains proteoglycans and a major part of them is ITI light chain (bikunin). The Kunitz inhibitor domain, a core protein of bikunin, has significant inhibitory activity on CaOx crystallization without GAG bound covalently to the core protein.

Adult↗

PubMed1999

Biologic and binding activities of IFN-alpha subtypes in ACHN human renal cell carcinoma cells and Daudi Burkitt's lymphoma cells.

Nine interferon-alpha subtypes, IFN-alpha1, IFN-alpha2, IFN-alpha5, IFN-alpha7, IFN-alpha8, IFN-alpha10, IFN-alpha14, IFN-alpha17, and IFN-alpha21, were separated from purified human lymphoblastoid IFN. We tested their inhibitory effects on cell growth and replication of Semliki Forest virus (SFV) and vesicular stomatitis virus (VSV) and their induction of 2',5'-oligoadenylate synthetase (2', 5'-OAS) in ACHN renal cell carcinoma cells. In terms of all three activities, the nine subtypes had similar relative activities, with IFN-alpha10 the most active and IFN-alpha1 the least. Their relative effects on cell growth were similar in two other human cell lines, SK-LU-1 lung cancer cells and KU-2 renal cell carcinoma cells, whereas cells of the Daudi Burkitt lymphoma line behaved quite differently, being highly sensitive to all the nine subtypes. The relative effects with ACHN cells correlated well with their relative binding affinities. However, each of the subtypes bound to both ACHN and Daudi cells to almost the same extent. This suggests that their profound inhibitory effects on the growth of Daudi cells are amplified at some stage in the signal transduction pathway or in the expression of genes that results from binding to the IFN-alpha receptor.

2',5'-Oligoadenylate Synthetase↗

PubMed1999

Tumor cell growth suppression by tannic acid.

Tannic acid was cultured together with tumor cells that had originated from human malignant tumors (HCT-15 & AGS). Significant suppression of tumor growth was observed. The 50% suppression was observed at the concentration between 50 micrograms/ml and 12.5 micrograms/ml. When tannic acid was injected into HCT-15 cells by electroporation at 1180 mu p and 200 ohm, the suppression rate was 34.3% at the concentration of 50 micrograms/ml in HBS solution. The suppression rate of cells only in contact with tannic acid solution for one hour under the same conditions as used for electroporation, was 26.1%. Histographic findings suggested that tannic acid almost completely blocked the S phase of the cell cycle.

Adenocarcinoma↗

PubMed1999

Tannic acid raises survival rate of mice bearing syngeneic tumors.

Tannic acid which was found earlier to have growth suppressive activity against cultured tumor cells, was given to Balb/c mice p.o. The mice had been inoculated with syngeneic tumor cells (Meth/A) i.p. When tannic acid was suspended in drinking water and given daily at doses of approximately 875 mg/kg/day and 1750 mg/kg/day, the respective survival rates were 59% and 48%, with that of the control mice being 29%. To study the cytotoxicity of tannic acid, we administered the tannic acid to mice at 875 and 1750 mg/kg/day for 35 days. The weight gain for each dose was lower than that of the control, although the difference was not significant. When tannic acid was given at 8750 mg/kg/day, the weight gain was significantly lower than the control. A histologic study did not show any pathological findings in the kidney, liver, or lungs in the mice given tannic acid at the above doses.

Administration, Oral↗

PubMed1999

Effect of gold on tumor-associated antigens.

A gold compound, which is an anti-rheumatoid agent, was clinically applied to patients showing a high level of tumor-associated antigens. Two patients showed no clear evidence of recurrence except for a high level of tumor-associated antigens. The gold compound was injected i.m. every week at the dose of 25 mg/body for 10 times to a patient showing a high CEA level that had arisen eight years after cervical dissection for a tongue carcinoma. It was also administered every other week for 30 times at the dose of 25 mg/body to a patient showing high CA19-9 and SLX levels five years after palliative left pulmonary resection followed by radiation therapy for left pulmonary carcinoma. The CEA level dropped to the normal limit after 10 injection and remained at that level after cessation of the gold treatment. SLX and CA19-9 levels of the second patient showed lower than initial values, although SLX did not fall to the normal range after the 30 injections. No side effects such as lowering of white blood cell count, BUN elevation, or kidney dysfunction were seen.

Aged↗

PubMed1999

Cellular and functional characterization of three recombinant antithrombin mutants that caused pleiotropic effect-type deficiency.

Inherited antithrombin deficiency is associated with a predisposition for familial venous thromboembolic disease. Pleiotropic effect-type mutants of antithrombin that have an amino acid replacement in a distal hinge region including strands 1C, 4B, and 5B of the polypeptide chain are known to exhibit impaired interactions with both thrombin and heparin, coupled with a secretion defect. To examine the mechanism of pleiotropic effect-type antithrombin deficiency, we expressed three mutants, Oslo (Ala404-->Thr), Kyoto (Arg406-->Met), and Utah (Pro407-->Leu), in baby hamster kidney (BHK) cells, and compared their secretion rates, affinities for heparin and abilities to form thrombin-antithrombin (TAT) complexes with those of wild-type (Wt) antithrombin. Pulse-chase experiments showed that the Oslo- and Kyoto-mutants were secreted at rates similar to Wt antithrombin. In contrast, the Utah-mutant underwent partial intracellular degradation. The intracellular degradation of the Utah-mutant was not inhibited by lysosomotropic inhibitors, but by proteasome inhibitors such as carbobenzoxy-L-leucyl-L-leucyl-L-leucinal (LLL) and lactacystin, indicating that a part of the Utah-mutant was degraded by proteasome through quality control in the endoplasmic reticulum (ER). Crossed immunoelectrophoresis in the presence of heparin showed that only the Oslo-mutant lacks heparin-binding ability. Incubation with thrombin showed that the Kyoto- and Utah-mutants, but not the Oslo-mutant, formed a weak but detectable TAT complex. Furthermore, heparin enhanced the TAT complex formation by the Kyoto- and Utah-mutants, suggesting heparin cofactor activities of these mutants. These results show that each of the Oslo-, Kyoto-, and Utah-mutants exhibits different properties as to secretion, intracellular degradation and functional activity, although they are grouped as pleiotropic effect-type mutants.

Amino Acid Sequence↗

PubMed1999

Structural characterization of the gene for human histidine-rich glycoprotein, reinvestigation of the 5'-terminal region of cDNA and a search for the liver specific promoter in the gene.

Genomic DNA libraries were screened for the human histidine-rich glycoprotein (HRG) gene and a sequence of 15,499 nucleotides was determined. The gene is composed of 7 exons and 6 introns, and all the exon-intron boundaries match the consensus GT/AG sequence for donor and acceptor splice sites. Each of cystatin-like domains I and II of HRG is encoded by three exons, exons I to III and exons IV to VI, respectively, like those of other members of the cystatin superfamily. The entire C-terminal half of the molecule is encoded by the largest exon, VII. The first 103 nucleotides of the cDNA sequence reported for human HRG [Koide, T., Foster, D., Yoshitake, S. , and Davie, E.W. (1986) Biochemistry 25, 2220-2225] could not be found in the determined gene sequence. A homology search of this sequence against a database showed the complete matching to a part of the yeast mitochondrial DNA encoding 21S ribosomal RNA. Rapid amplification of cDNA 5' ends (5'-RACE) analysis revealed that the cDNA has multiple 5'-ends and that a possible starting point is nucleotide 104 of the reported cDNA sequence. These results suggest that the first 103 nucleotides of the cDNA sequence reported for human HRG originated from yeast mitochondrial DNA and were incidentally incorporated into the HRG cDNA in the process of the construction of a cDNA library. Various fragments obtained on restriction endonuclease digestion of the 5'-noncoding region of the HRG gene were ligated to the chloramphenicol acetyltransferase (CAT) gene and then transfected into HepG2 and 293 cells to analyze the promoter activity. The sequence between -262 and -21 from the putative translation initiation site supported the expression of CAT in HepG2 cells but not in 293 cells, suggesting that this segment promotes the liver-specific transcription of the human HRG gene.

5' Untranslated Regions↗