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E Takeda

Publications and source records attributed to E Takeda.

At least 91 records · Page 5Linked to original sources
PubMed1995

Activation of ornithine decarboxylase in epithelial cells of rat intestine.

Intestinal ornithine decarboxylase (ODC) is strongly induced by dietary amino acid and protein feeding. However, the consequence of this induction is unknown. In this study, we analyzed the relationship between intestinal ODC activity and DNA synthesis in villus and crypt cells of rat intestine. Single amino acid diets and protein diets stimulated ODC activity in villus cells, but not in crypt cells. However a 20% casein diet induced ODC activity and increased the putrescine concentration in villus and crypt cells. Administration of alpha-difluoromethylornithine, a suicide inhibitor of ODC, prevented both an increase in putrescine level and DNA synthesis in the crypt cells. Observations suggested that the induction of ODC is necessary to initiate DNA synthesis in rat intestinal epithelium.

Animals↗
PubMed1995

Chromosome assignments of genes for human Na(+)-dependent phosphate co-transporters NaPi-3 and NPT-1.

Chromosome assignments for the genes encoding human renal high affinity Na/phosphate co-transporters NaPi-3 and NPT-1 were derived by analyzing somatic cell hybrid DNAs. Polymerase chain reaction (PCR), using primers specific for two human Na/Pi co-transporters demonstrated that the genes for NaPi-3 was assigned to human chromosome 5 while that for NPT-1 was assigned to human chromosome 6. Renal phosphate transporter genes may be candidates for causing hereditary hypophosphatemia with hypercalciuria in humans.

Base Sequence↗
PubMed1995

[HLA-DQB2 genotypes analyzed by PCR/SSCP method].

When the PCR products amplified by the primers prepared at the 11th HLA Workshop (DQBAMP-A, DQBAMP-B) were analyzed directly by the SSCP method, one or two pairs of characteristic bands were detected other than those attributed to DQB1, and a total of three kind of paired bands were detected. To confirm that these bands were allelic genes of DQB2, the corresponding bands were isolated by cloning, and their base sequences were determined. The base sequence of one of them was in agreement with that of DX beta, which has already been described, and the characteristic 3-base defect was noted by comparison with the base sequence of DQB1. The same 3-base defect was noted also in the other two kinds. One-base substitution was present in each of the three kinds of base sequence, and they were confirmed to be allelic genes of DQB2. In DQB1 typing by the PCR/SSCP method of Carrington et al., treatment with the restriction enzyme Alu 1 is needed to eliminate DQB2. However, the use of this enzyme was theoretically demonstrated to be inappropriate, because it degraded the DQB1*0401 gene.

Base Sequence↗
PubMed1994

Vitamin D-dependent rickets type II: regulation of human osteocalcin gene expression in cells with defective vitamin D receptors by 1,25-dihydroxyvitamin D-3, retinoic acid, and triiodothyronine.

The vitamin D receptor (VDR) is a nuclear transcription factor which binds to the vitamin D response element (VDRE) of the human osteocalcin gene and regulates its expression. Humans with VDR gene mutations, ever among those with the same point mutation in their VDR gene, demonstrate clinical heterogeneity. In addition, in some patients with these mutations, rickets has not recurred following cessation of therapy during follow-up ranging from 6 to 24 years. While important, it is likely that the VDR protein is not the sole factor in the development of rickets. To try to understand these clinical findings, the complex formed between the VDRE and one or more proteins in the nuclear extracts of cultured skin fibroblasts treated with 1,25-dihydroxyvitamin D-3 (1,25(OH)2D3), retinoic acid (RA), and/or triiodothyronine (T3) was investigated since such complexes are likely to precede the transcription of the VDR gene. Complex formation in the control cells with an intact VDR was increased by treatment with either 0.1 nM, 1 nM, 10 nM 1,25(OH)2D3, 100 nM RA, or 100 nM T3; however, combinations of these compounds did not produce an additive effect. In cells of affected patients, 1,25(OH)2D3, RA, or T3 increased complex formation, while no combination had an additive effect. These results indicate that 1,25(OH)2D3, RA, and T3 play a role in the regulation of bone remodeling through modulating the formation of protein complexes on the VDRE. Therefore, the clinical observations in patients with a VDR mutation might be explained at least in part by the overlapping control of osteocalcin expression by 1,25(OH)2D3, RA and T3.

Base Sequence↗
PubMed1994

Characterization of the rabbit intestinal fructose transporter (GLUT5).

Recent studies suggest that the jejunal/kidney-type facilitative glucose transporter (GLUT5) functions as a high-affinity D-fructose transporter. However, its precise role in the small intestine is not clear. In an attempt to identify the fructose transporter in the small intestine, we measured fructose uptake in Xenopus oocytes expressing jejunal mRNA from five species (rat, mouse, rabbit, hamster and guinea-pig). Only jejunal mRNA from the rabbit significantly increased fructose uptake. We also cloned a rabbit GLUT5 cDNA from a jejunal library The predicted amino acid sequence of the 487-residue rabbit GLUT5 showed 72.3 and 67.1% identity with human and rat GLUT5 respectively. Northern-blot analysis revealed GLUT5 transcripts in rabbit duodenum, jejunum and, to a lesser extent, kidney. After separation of rabbit jejunal mRNA on a sucrose density gradient, the fractions that conferred D-fructose transport activity in oocytes also hybridized with rabbit GLUT5 cDNA. Hybrid depletion of jejunal mRNA with a GLUT5 antisense oligonucleotide markedly inhibited the mRNA-induced fructose uptake in oocytes. Immunoblot analysis indicated that GLUT5 (49 kDa) is located in the brush-border membrane of rabbit intestinal epithelial cells. Xenopus oocytes injected with rabbit GLUT5 cRNA exhibited fructose uptake activity with a Km of 11 mM for D-fructose. D-Fructose transport by GLUT5 was significantly inhibited by D-glucose and D-galactose. D-Fructose uptake in brush-border membrane vesicles shows a Km similar to that of GLUT5, but was not inhibited by D-glucose or D-galactose. Finally, cytochalasin B photolabelled a 49 kDa protein in rabbit brush-border-membrane preparations that was immunoprecipitated by antibodies to GLUT5. Our results suggest that GLUT5 functions as a fructose transporter in rabbit small intestine. However, biochemical properties of fructose transport in Xenopus oocytes injected with GLUT5 cRNA differed from those in rabbit jejunal vesicles.

Amino Acid Sequence↗
PubMed1994

Molecular analysis of abnormal pyruvate dehydrogenase in a patient with thiamine-responsive congenital lactic acidemia.

A patient who responded to thiamine therapy with reduction of lactate in the blood and cerebrospinal fluid and clinical improvement was studied. Cultured lymphoblastoid cells of this patient were found to show reduced activities of pyruvate dehydrogenase complex (PDHC) and pyruvate dehydrogenase, decreased affinity of PDHC for thiamine pyrophosphate, and defective activation of PDHC by pyruvate dehydrogenase phosphatase. PDHC deficiency in fibroblasts and biopsied muscle of this patient was also due to the decreased affinity of PDHC for thiamine pyrophosphate. A mutation in the E1 alpha subunit containing the thiamine binding site and serine phosphorylation site regulating the activation/inactivation of PDHC was characterized by the polymerase chain reaction and DNA sequencing. A single A-->G transition was identified at position 131, resulting in the substitution of Arg-44 for His-44. This mutation must be a de novo mutation because it was not found in either parent's genomic DNA. In this study, we have obtained the first evidence at the molecular level for a mutation of thiamine-responsive PDHC deficiency.

Acidosis, Lactic↗
PubMed1994

Detection of carboxyhemoglobin using Fourier transform infrared microspectroscopy.

We investigated the absorption of carboxyhemoglobin (COHb) using a Fourier transform infrared (FTIR) microscopy system. Weak absorption at 1969 cm-1 due to Fe<--CO and strong absorption due to N-H stretching vibration, > C = O stretching vibration and -NH bending vibration (1544 cm-1) were observed. The ratio of absorbance at 1969 cm-1/1544 cm-1 can be used as an index of CO saturation. Therefore, when formalin-fixed blood remains in blood vessels in formalin-fixed tissues, the amount of COHb can be calculated using this FTIR microscopy system.

Animals↗
PubMed1993

[Clinical experience with S-1108 on bacterial infection in the pediatric field].

The effects of S-1108, an orally active cephem antibiotic newly synthesized by Shionogi Res. Lab., on pediatric bacterial infections was studied. S-1108 was administered orally at a daily dose between 9.3 and 12.4 mg/kg in three divided doses (after each meal) for 5 to 11 days to patients with pharyngitis (2), tonsillitis (1), bronchitis (3), pneumonia (1), lymphadenitis (1), enteritis (1) and cystitis (1). The clinical efficacy rate was 100% with excellent responses in 3, good in 6 and undetermined in 1. Bacteriological effects observed indicated that one strain each of Streptococcus pneumoniae, Streptococcus pyogenes, Klebsiella pneumoniae and two strains of Haemophilus influenzae were eradicated by the treatment. No clinical side effects and laboratory test abnormalities were observed at all in this study. These results suggested that S-1108 would be a useful antibiotic for the treatment of bacterial infections in the pediatric field.

Administration, Oral↗
PubMed1993

Overcoming of vincristine resistance in HL-60 human promyelocytic leukemia cell line by dipyridamole.

Dipyridamole enhanced the anti-cancer activity of VCR toward both wild type HL-60 and VCR-resistant subline, HL-60/R, which had a 15 fold greater resistance to VCR as compared with the wild type cell line. The resistance to VCR of HL-60/R cells was associated with a marked decrease in the intracellular VCR accumulation. After incubation with VCR for 24 hrs, 0.61 and 0.24 pmol VCR per one million cells were accumulated in the wild and the resistant cells, respectively. Dipyridamole dose-dependently increased the intracellular VCR accumulation in the wild type cells and also it restored the intracellular VCR accumulation in the VCR-resistant cells. Addition of 10 microM dipyridamole to the culture medium enhanced the intracellular accumulation of VCR during 24 hr incubation by 2.6 fold and 6.0 fold in HL-60 and HL-60/R cells, respectively. The VCR-resistance in HL-60/R cells was able to be overcome by the addition of 2.5 microM dipyridamole to the culture medium. This concentration of dipyridamole could be obtained by the intravenous administration without severe adverse effects. These results indicate that dipyridamole should be effective in the treatment of patients with hematologic malignancy resistant to VCR.

Dipyridamole↗
PubMed1993

[Vitamin D dependency and vitamin D resistance].

Vitamin D dependency is classified into two clinical disorders which are caused by genetic defect of vitamin D metabolism. Vitamin D dependent rickets type I and type II are the deficiency of 25-hydroxyvitamin D-1 alpha-hydroxylase and the defect of receptor for 1 alpha,25-dihydroxyvitamin D, respectively. In contrast, vitamin D resistance shows hypophosphatemia derived from disorder(s) of phosphate transport system in renal brush border membrane. There are three clinical entities such as hereditary hypophosphatemic rickets with hypercalciuria, familial hypophosphatemic rickets and oncogenic hypophosphatemic osteomalacia. However, the real pathogenesis of these disorders have not well been understood at present.

Humans↗
PubMed1993

Mechanism of the discrepant effect of a combination of methotrexate plus dipyridamole on human hematologic cell lines.

Mechanisms of the discrepant effect of methotrexate and dipyridamole on human hematologic cultured cell lines were investigated by analyzing intracellular methotrexate levels and thymidine incorporation through the salvage pathway, since the combination of methotrexate and dipyridamole has different effects according to cell type: additive effects on ML-1 and THP-1 (myelo-monocytoid cells); reduced effects on MOLT-3, SKW-3, P32/ish and BL-TH (lymphoid cells). Dipyridamole reduced the toxicity of methotrexate by diminishing intracellular methotrexate levels in MOLT-3 and BL-TH (lymphoid cells), in which the reduction of intracellular methotrexate affected more than just the blocking of the salvage pathway required for growth by dipyridamole. On the other hand, dipyridamole enhanced the toxicity of the combination by blocking the salvage pathway in an ML-1 (myelo-monocytoid cell) and in a methotrexate-resistant subline of BL-TH/MTX (lymphoid cell), in which the salvage pathways were considered activated. Dipyridamole could prove to be a useful drug for reversing the drug resistance caused by the activation of the salvage pathway.

Adult↗
PubMed1992

Decrease of pyruvate dehydrogenase phosphatase activity in patients with congenital lactic acidemia.

We developed an assay method for pyruvate dehydrogenase phosphatase activity using [1-14C]pyruvate and measured pyruvate dehydrogenase phosphatase activity in cultured skin fibroblasts from three patients with congenital lactic acidemia due to a defect in activation of the pyruvate dehydrogenase complex. The enzyme activity of their fibroblasts was significantly reduced to 50.7%, 64.6% and 63.1% of that of control fibroblasts. These observations suggest that the defect in activation of the pyruvate dehydrogenase complex in these patients might be due to a reduction in pyruvate dehydrogenase phosphatase activity.

Acidosis, Lactic↗
PubMed1992

Mutation of E1 alpha gene in a female patient with pyruvate dehydrogenase deficiency due to rapid degradation of E1 protein.

A mutation of an insertion of 4 bp in the gene for the alpha subunit of pyruvate dehydrogenase (E1 alpha) was found in a female with pyruvate dehydrogenase deficiency due to the rapid degradation of alpha and beta subunit proteins of pyruvate dehydrogenase. This mutation caused a frameshift that altered the amino acid sequence and created a premature stop codon. This 4-bp insertion has been found in an unrelated female patient with E1 alpha deficiency. It is rare that the same mutation is found in unrelated patients with this rare inborn error of metabolism. Furthermore, short deletions or duplications in the E1 alpha gene of patients with E1 alpha deficiency have been found only in exons 10 and 11. These exons may be hot spots for the mutations by the recombinational processes. This patient was heterozygous for the normal and a mutant allele. However, in most of the cultured skin fibroblasts from this patient, the mutant allele was expressed. These observations suggest that the X chromosome containing the normal allele was predominantly inactivated so that she developed lactic acidaemia and neurological abnormalities despite being heterozygous. The mutant alpha subunit protein failed to form a stable structure of pyruvate dehydrogenase, so that both alpha and beta subunit proteins were degraded rapidly.

Alleles↗
PubMed1992

A female patient with Lesch-Nyhan syndrome.

The authors report the second case of a female with typical Lesch-Nyhan syndrome. She exhibited athetoid movement, self-multilation, mental retardation and spasticity. Laboratory investigations revealed hyperuricaemia, hyperuricosuria and decreased erythrocyte hypoxanthine guanine phosphoribosyl transferase activity. She has normal female external genitalia and karyotype. Her parents are non-consanguineous and there is no family member with gout, nephropathy or any psychoneurological disorder. To prevent self-stimulation, it was necessary to fix the patient's upper extremities to the backrest of her wheelchair. The authors also describe an apparatus that limits elbow flexion.

Child↗
PubMed1992

Suspected distinct activation pathways of human lymphocytes induced by antilymphocyte globulin and anti-CD3 monoclonal antibody result in different secretion of hematopoietic colony-stimulating activities.

We evaluated the activation sequence of peripheral blood lymphocytes from healthy donors using different mitogens, including antilymphocyte globulin (ALG), anti-CD3 monoclonal antibody (OKT3), and phytohemagglutinin (PHA). Blood mononuclear cells stimulated by ALG, OKT3 and PHA incorporated 3H-thymidine in the same way. When enriched T cells were tested in the presence of interleukin-1 alpha (0 to 100 U/ml, incorporation of 3H-thymidine was greater in those cells stimulated by ALG than by PHA. OKT3 did not activate enriched T cells. Thymidine incorporation was reduced to less than 50% of maximum concentrations by the addition of 10(-7) mol/1,25-dihydroxyvitamin D3 (vit D3) in PHA- or OKT3-activated cells. However, the inhibitory effect of vit D3 was not apparent in ALG-activated cells. Production of granulocyte-macrophage colony-stimulating factor and interleukin-3 by lymphocytes upon activation was consistently higher when cells were treated with ALG or PHA than with OKT3. Taken together, the data indicate that there appear to be distinct functional mechanisms between ALG- and OKT3-induced lymphocyte activation that lead to characteristic immunohematologic events.

Antibodies, Monoclonal↗
PubMed1992

[Clinical study on cefprozil fine granules].

Cefprozil (CFPZ, BMY-28100), a new non-ester cephem, was administered to 15 pediatric patients with infectious diseases. The patients included 6 boys and 9 girls from 10 months to 11 years old and they were given oral doses of 18.5-41.7 mg/kg/day for 3 to 8 days. Clinical efficacies were excellent in 3 cases and good in 12 cases, hence the total efficacy rate was 100%. Eosinophilia occurred in 1 case as side effect of the drug, but no other side effects were not found during or after the treatment.

Administration, Oral↗
PubMed1992

[A case of periodic ataxia].

We report a sporadic case of periodic ataxia characterized by recurrent attacks of vertigo and ataxia. A 62-year-old male was known to have nystagmus at the age of 18. He has had recurrent episodes of vertigo and ataxia since the age of 48. During an attack remarkable downbeat nystagmus, limb ataxia predominant in the lower extremities and ataxic gait were present. MRI demonstrated an atrophy of the anterosuperior region of the cerebellar vermis. Vertical nystagmus, dysesthesia of gloves and stocking type and deep sensory disorder persisted during interictal intervals. There is no finding which supports this case to be vascular disorder, congenital anomaly, tumor, infection or demyelinating disease. We thought this case to be periodic ataxia and to belong to vestibulocerebellar ataxia reported by Farmer and his colleagues.

Cerebellar Ataxia↗