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T Ikeuchi

Publications and source records attributed to T Ikeuchi.

At least 235 records · Page 13Linked to original sources
PubMed1986

Characterization of nucleoside-diphosphate kinase-associated guanine nucleotide-binding proteins from HeLa S3 cells.

Nucleoside-diphosphate (NDP) kinase-associated [alpha-32P]GTP-incorporating proteins from HeLa S3 cells have been biochemically characterized. Two distinct NDP-kinases (F-I and F-II) had been partially purified from HeLa S3 cells by Sephacryl S-300 gel filtration and DEAE-cellulose column chromatography. The [alpha-32P]GTP-incorporating proteins (approx. Mr 20,000) could be separated from NDP-kinases (approx. Mr 80,000) by 5-25% glycerol density-gradient centrifugation analysis after treatment with 7 M urea in the presence of 1 mM EDTA. [alpha-32P]GTP incorporation into these two proteins (G1 and G2) from NDP-kinases required 5 mM Mg2+ and was highly inhibited by either GDP or GTP analogues, such as guanylyl imidodiphosphate and guanylyl methylenediphosphate. [3H]GDP, but no other nucleoside 5'-diphosphates, was also bound to these two proteins in the presence of Mg2+ (5 mM). Moreover, incubation of [alpha-32P]GTP with either G1 or G2 in the presence of Mg2+ (5 mM) resulted in the formation of [32P]GDP and Pi. The data presented here indicated that the guanine nucleotide-binding activity, the GTPase activity, and the molecular weight (approx. Mr 20,000) of NDP-kinase-associated proteins from HeLa S3 cells are similar to those reported for ras oncogene products (p21 proteins).

Calcium↗
PubMed1986

Rapid induction of nucleoside-diphosphate kinase in HeLa S3 cells by human-type interferons.

Nucleoside-diphosphate (NDP)-kinase can be considered to be induced by human-type interferons (HuIFNs) rapidly, since an enzyme increase was detected within 2 h of incubation of HeLa S3 cells with HuIFNs, while incubation with heterologous mouse IFNs had no such effect. The enzyme increase induced by HuIFNs reached a plateau at 6 h after treatment. Actinomycin D (0.5 microgram/ml) significantly blocked the enzyme increase induced by HuIFNs in the cells. A possible biological role of the enzyme in the IFN-induced biochemical events is discussed.

Adenosine Diphosphate↗
PubMed1986

Amino-terminal structure of spoOA protein and sequence homology with spoOF and spoOB proteins.

The previously reported nucleotide sequence of the spoOA coding region of Bacillus subtilis suggested that the protein is initiated with either of two possible initiation codons, ATG and GTG, 84 base pairs apart. To determine which codon is utilized as an initiator in B. subtilis, we constructed a fusion gene in which the promoter and NH2-terminal region of the spoOA gene was connected to the chloramphenicol acetyltransferase gene (cat gene). After introduction of the plasmid carrying the spoOA-cat fusion gene into B. subtilis cells, the fusion protein was purified by affinity chromatography. The sequence of NH2-terminal amino acids of the fusion protein was determined and the result established that the GTG codon is utilized as an initiator in B. subtilis. Comparison of the amino acid sequences revealed a marked homology between the spoOA (NH2-terminal half) and spoOF proteins. A less striking but significant homology was also found between the spoOA (COOH-terminal half) and spoOB proteins. This suggests the presence of a common functional domain structure for these proteins that are supposed to play key regulatory roles in sporulation.

Acetyltransferases↗
PubMed1986

[Clinical studies of efficacy of piperacillin against complicated urinary tract infections].

Clinical efficacy of piperacillin against 74 cases with complicated urinary tract infection was examined. Piperacillin was administered at the dose of 4 g (2 g twice daily) through intravenous drip infusion. The overall clinical value was rated in "excellent", in 9 cases, "moderate" in 34 cases and "poor" in 31 cases with a total efficacy of 58.1%. In the analysis of clinical values based on background, its efficacy was statistically significantly lower in the patients at a higher age, those with complication of diabetes mellitus, and those with indwelling catheter. In operated cases compared to non-operated cases, it was suggested to be more effective for improving the disturbances in urinary flow as a result of the removal of the underlying conditions by the operation. As to bacteriological efficacy, 64 out of 95 strains (67.4%) isolated were eradicated following its administration. Microbes which appeared after its dosing belonged to 9 classes of 18 strains, of which 5 strains (27.8%) of Serratia were identified. Side effects were 2.5% (3/119), no serious cases appeared. Changes in laboratory examination results were elevated GOT (2.5%), GPT (1.7%), and ALP (0.8%) values, all being transient hanges.

Adult↗
PubMed1985

Nucleotide sequences of the sporulation gene spo0A and its mutant genes of Bacillus subtilis.

We have determined the nucleotide sequence of a 2375-base-pair DNA fragment, which contained the sporulation gene spo0A cloned from Bacillus subtilis. The sequence had only one long open reading frame consisting of 239 codons, which was found to correspond to the spo0A gene by comparing the nucleotide sequence of the wild-type gene with those of the mutant alleles. The calculated molecular weight of the product of the wild-type spo0A gene was 26,500. We found also a new mutation, sgi, which maps within the spo0A gene. This mutation relieves the growth inhibition of the host cells caused by a multicopy plasmid carrying the spo0A gene. The mutations spo0A12, spo0C9V, and sgi-1 were found to be an amber mutation at the 62nd codon, a missense at the 229th codon, and a frame-shift at the 223rd codon of the spo0A gene, respectively.

Bacillus subtilis↗
PubMed1985

In vitro and in vivo activities of DN-9550, a new broad-spectrum cephalosporin.

DN-9550 [(6R, 7R)-7-[(Z)-2-(2-aminothiazol-4-yl)-2-(1H-imidazol-4-yl) methoxyiminoacetamido]-3-[(1-pyridinio)methyl]-8-oxo-5-thia -1-azabicyclo methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate hydrochloride] is a new semisynthetic cephalosporin with a broad spectrum of antibacterial activity against gram-positive and gram-negative bacteria. The activity of DN-9550 against most species of the family Enterobacteriaceae was roughly comparable to that of ceftazidime, slightly lower than that of cefotaxime, and far exceeded that of cefoperazone. Against Citrobacter freundii, Enterobacter cloacae, and Serratia marcescens, DN-9550 was more active than ceftazidime and cefotaxime. DN-9550 and ceftazidime were significantly more active than cefotaxime against Pseudomonas aeruginosa, but DN-9550 and cefotaxime were clearly more active than ceftazidime against staphylococci and streptococci. Haemophilus influenzae and Neisseria gonorrhoeae were also highly susceptible to DN-9550, but Bacteroides fragilis was generally not susceptible to the compound. DN-9550 was stable to various types of beta-lactamases and had high affinities for penicillin-binding protein 3 of both Escherichia coli and P. aeruginosa. When DN-9550 was administered subcutaneously to mice experimentally infected with Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumoniae, Serratia marcescens, or Pseudomonas aeruginosa, its efficacy well reflected its in vitro potency.

Animals↗
PubMed1985

Genetic analysis of spo0A and spo0C mutants of Bacillus subtilis with a phi 105 prophage merodiploid system.

An 8.0-kilobase chromosomal fragment of Bacillus subtilis which contained an intact spo0A gene was recloned onto temperate phage phi 105 from the rho 11dspo0A+-1 transducing phage. A specialized transducing phage, phi 105-dspo0A+-1, was constructed and used to transduce the spo0A12 mutant strain 1S9. A Spo+ transductant which was a single lysogen of the phi 105dspo0A+-1 transducing phage was isolated. From competent cells of this Spo+ transductant was isolated a Spo- (Spo0A) strain which was immune to phi 105. It was used to prepare a lysate of the phi 105dspo0A12 phage. Transduction of the spo0C9V recE4 strain with the phi 105dspo0A12 and phi 105dspo0A+-1 phages was carried out. The phi 105dspo0A+-1 phage gave rise to a large number of heat-resistant cells, but the phi 105dspo0A12 phage formed no heat-resistant cells. These results indicate that the spo0A12 and spo0C9V mutant genes do not complement each other in the ability to sporulate and that the spo0C9V mutation is located within the spo0A gene. Although the spo0C9V strain was completely asporogenous, the spo0C9V/spo0C9V diploid strain produced heat-resistant cells at a frequency of ca. 10(-3) in the sporulation medium. This result indicates that two copies of the spo0C9V mutant gene partially restore the ability of these cells to sporulate.

Alleles↗
PubMed1985

[An experience in the treatment of severe surgical infectious diseases with combination of antibiotics and human gammaglobulin (SM-4300)].

The human immunoglobulin (SM-4300), which was developed by Travenol Laboratories, Inc. U.S.A., was used with antibiotics on 12 cases of severe surgical infectious disease. The method of administration and the evaluation of clinical effect of gammaglobulin (SM-4300) were made based upon the criteria of the SM-4300 study group. The clinical evaluation of the effect was classified in 5 grades; excellent, good, fair, poor and unknown. Three types of administration dose schedules were employed. Severe surgical infections were 3 cases of postoperative pneumonia, 3 cases of sepsis with pneumonia, 3 cases of peritonitis, 1 case of cholangitis, 1 case of sepsis with perinephritis and 1 case of subphrenic abscess. Bacterial and immunological examination were also performed before and after the administration of SM-4300. Evaluable cases were 10 cases out of 12 cases. Clinical effects of the administration of SM-4300 were evaluated as excellent in 1 case, good in 3, fair in 2 and poor in 4.

Adult↗
PubMed1985

[Rare cases of pheochromocytoma. A report of two cases].

Two rare cases of pheochromocytoma were reported. Case 1 was 39-year-old housewife who was referred for history of high fever with left hypochondralgia twice in the previous 15 months before coming to our department. The patient had neither elevation of blood pressure nor that of central and peripheral venous catecholamine concentration. A left suprarenal mass was found in CT, which was suggested to be a cyst due to the numerical value between 23-24. Further ultrasonographic study indicated a solid tumor. Left adrenalectomy was done. Histologically, some of the viable atypical adrenal cells were found in the capsulating tissue contained the necrotic material which was almost occupying the entire mass. Case 2 was a 64-year-old female with hypertension who was admitted for further examination. On the hospital course, the blood pressure returned to normal without medication. Circulating blood volume was extremely reduced (below 1/2 of normal), the replacement of which raised the blood pressure to cause hypertension. An angiographic study indicated only a right adrenal mass, whereas left adrenal venous catecholamine concentration was significantly higher than that of the right side. After confirming right adrenal with no other disorders by CT scan, right adrenalectomy was carried out. Intraoperative correction of hypertension has been sustained and cardiovascular symptoms have disappeared.

Adrenal Gland Neoplasms↗
PubMed1984

Identification of the sporulation gene spoOA product of Bacillus subtilis.

A 2.4-kilobase fragment of the Bacillus subtilis chromosome containing the wild-type spoOA gene derived from the phi 105dspoOA+-Bc-1 transducing phage was cloned onto plasmid pBR322 in Escherichia coli. A recombinant plasmid harboring the mutant spoOA12 allele on the 2.4-kilobase insert was also constructed from the phi 105dspoOA12-1 phage DNA and pBR322. Protein products synthesized in response to plasmid DNA in a DNA-directed cell-free system derived from E. coli were analyzed by sodium dodecyl sulfate-polyacryl-amide gel electrophoresis. A protein of approximately 27,500 daltons synthesized with the recombinant plasmid DNA harboring the wild-type spoOA gene as template was not formed with the recombinant plasmid DNA harboring the spoOA12 allele. Since the spoOA12 mutation is a nonsense mutation, we conclude that the 27.5-kilodalton protein is the product of the spoOA gene.

Alleles↗
PubMed1984

Effect of dehydroepiandrosterone sulfate on collagenase production in rabbit uterine cervix culture.

Rabbit uterine cervical explants were found to produce a typical collagenase, latent form, in tissue culture, 4-Aminophenylmercuric acetate and trypsin were potent activators of the enzyme. The enzyme was purified simply in one step of CM-52 cellulose ion-exchange chromatography, and then further characterized. Addition of dehydroepiandrosterone sulfate (DHAS) to culture medium significantly stimulated collagenase production, but DHAS did not directly activate the enzyme. In addition, dehydroepiandrosterone and 17 beta-estradiol, the main metabolites of DHAS in vivo, depressed enzyme production. Our previous result, that increases in cytoplasmic DHAS-binding protein in rabbit uterine cervices parallel the progress of pregnancy, and these results suggest that DHAS might have direct actions toward cervical ripening.

Animals↗
PubMed1984

Inhibitory effect of ethidium bromide on mitotic chromosome condensation and its application to high-resolution chromosome banding.

Ethidium bromide (EB) is known to intercalate between stacked base pairs without specific base-pair preference. Its use in cultured human lymphocytes and Burkitt's lymphoma cells resulted in the accumulation of cells in prophase and prometaphase stages. Inhibition of mitotic chromosome condensation as a possible mechanism involved in this phenomenon is discussed. A simple method for obtaining high-resolution banding patterns on elongated chromosomes was devised as follows: Human lymphocytes cultured for 3 days with phytohemagglutinin were exposed to EB (5-10 micrograms/ml) and Colcemid (0.02 micrograms/ml) simultaneously for 2 h and then routinely harvested for chromosome preparation. High-resolution G-bands were obtained by Giemsa staining following mild trypsin treatment.

Burkitt Lymphoma↗