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J Ito

Publications and source records attributed to J Ito.

At least 271 records · Page 15Linked to original sources
PubMed1987

Primary structure of the DNA terminal protein of bacteriophage PRD1.

The genome of a lipid-containing phage, PRD1, is replicated by a protein-priming mechanism. We have determined the nucleotide sequence of the PRD1 gene 8 which specifies the terminal protein, the protein primer for DNA synthesis. The coding region is 780 base pairs long and encodes for 259 amino acids (29,326 daltons). The predicted amino acid sequence of the PRD1 terminal protein reveals no substantial homology with that of any known terminal protein. However, hydropathy profiles of the PRD1, phi 29, and Nf terminal proteins are remarkably similar, suggesting a common evolutionary origin. A particular tyrosine residue is predicted to be covalently linked to the 5' end of the PRD1 DNA. The initiation codon ATG of gene 8 is preceded by the identifiable ribosome binding site, and putative promoter sequences. There are unique palindromic sequences between the ribosome binding site and "-10" region.

Amino Acid Sequence↗
PubMed1987

Nucleotide sequence of Bacillus phage Nf terminal protein gene.

The nucleotide sequence of Bacillus phage Nf gene E has been determined. Gene E codes for phage terminal protein which is the primer necessary for the initiation of DNA replication. The deduced amino acid sequence of Nf terminal protein is approximately 66% homologous with the terminal proteins of Bacillus phages PZA and luminal diameter 29, and shows similar hydropathy and secondary structure predictions. A serine which has been identified as the residue which covalently links the protein to the 5' end of the genome in luminal diameter 29, is conserved in all three phages. The hydropathic and secondary structural environment of this serine is similar in these phage terminal proteins and also similar to the linking serine of adenovirus terminal protein.

Amino Acid Sequence↗
PubMed1987

Modification of vestibular-induced pause neuron firing during anesthesia and light sleep.

Anatomic and electrophysiologic evidence suggests there is a vestibular input to eye movement-related pause neurons in the midline of the pontine reticular formation of the cat. The present investigation sought to explore the functional significance of this vestibular drive by examining pause neuron response to horizontal rotational stimulation as cats were anesthetized with halothane or went into natural light sleep. Anesthesia unmasks the vestibular input to pause neurons in that during anesthesia, pause neurons continue to fire but their firing rate is modulated by vestibular stimulation. The particular response patterns of pause neurons to anesthesia are not uniform. We suggest that the results observed could be explained if pause neurons received input from both vestibular nuclei, either directly or possibly via the prepositus hypoglossi.

Abducens Nerve↗
PubMed1987

Application of computed tomography for diagnosis of alveolar bony defects.

This study was performed to evaluate the usefulness of computed tomography (CT) in analyzing the three-dimensional structure of alveolar bony defects. The result showed that differences between CT film and actual readings from the cusp ridge to the bone crest were negligible, and the reading on CT film was underestimated approximately 1 mm at the distance from the cusp ridge to the bottom of the bony defect. By reading a series of CT films, one can easily evaluate the type of bony defects. Therefore, application of CT maybe useful for analyzing three-dimensional structure and diagnosis of the alveolar bony defects.

Adult↗
PubMed1987

Characterization of a deletion mutant of bacteriophage phi 29.

A spontaneous deletion mutant of bacteriophage phi 29 (phi 29 delta 1) has been characterized. This mutant has a 1112-bp deletion, which covers almost the entire sequence of genes 14 and 15, including an early promoter (B2). While lysis is very delayed, the phage DNA synthesis and internal phage development appear to be normal in the cells infected with this deletion mutant. These results indicate that the early functions are intact in phi 29 delta 1. Our results also suggest that genes 14 and 15 are dispensable for bacteriophage phi 29 growth and that the B2 promoter may also be dispensable for early functions in phi 29.

Bacteriophages↗
PubMed1987

Disappearance of a tumor shadow fed by the tentorial artery after embolization of the external carotid artery.

The tentorial artery is a branch of the meningohypophyseal trunk originating from the internal carotid artery; this artery sometimes becomes an enlarged feeding artery in patients with tentorial lesions, especially tentorial meningiomas. We experienced a case of a cerebellopontile angle meningioma whose angiogram revealed the disappearance of a feeding artery arising from the tentorial artery after embolization of the external carotid artery. We report this case and discuss the mechanism of this phenomenon.

Carotid Artery, External↗
PubMed1987

Functional dissociation of dual activities of glia maturation factor: inhibition of glial proliferation and preservation of differentiation by glial growth inhibitory factor.

Glial growth inhibitory factor (GGIF), derived from the culture medium of mouse neuroblastoma cell (NAs-1), lowered the DNA synthesis and cell multiplication of normal rat glioblasts induced by glia maturation factor (GMF). The inhibitory action of GGIF depended on the concentration of GMF in the culture medium, and was of an uncompetitive type on kinetic analysis. GGIF showed the inhibitory activity at a late stage of the G1 phase or early stage of the S phase. The factor, however, failed to inhibit the differentiation-promoting activity of GMF. The data strongly suggest that the dual activities of GMF, the promotion of glial proliferation and differentiation, may be elicited by mutually independent intracellular processes.

Animals↗
PubMed1987

Bacteriophage PRD1 DNA polymerase: evolution of DNA polymerases.

A small lipid-containing bacteriophage PRD1 specifies its own DNA polymerase that utilizes terminal protein as a primer for DNA synthesis. The PRD1 DNA polymerase gene has been sequenced, and its amino acid sequence has been deduced. This protein-primed DNA polymerase consists of 553 amino acid residues with a calculated molecular weight of 63,300. Thus, it appears to be the smallest DNA polymerase ever isolated from prokaryotic cells. Comparison of the PRD1 DNA polymerase sequence with other DNA polymerase sequences that have been published yielded segmental but significant homologies. These results strongly suggest that many prokaryotic and eukaryotic DNA polymerase genes, regardless of size, have evolved from a common ancestral gene. The results further indicate that those DNA polymerases that use either an RNA or protein primer are related. We propose to classify DNA polymerases on the basis of their evolutionary relatedness.

Amino Acid Sequence↗
PubMed1987

Cloning and purification of a unique lysozyme produced by Bacillus phage phi 29.

A DNA fragment of the bacteriophage phi 29 chromosome, encoding the entire sequence of phi 29 gene 15, has been cloned into the Escherichia coli expression vector pPLc245 under the control of the phage lambda major leftward promoter, PL. Upon heat induction, a protein with an apparent molecular mass of 26 kDa was overproduced. The molecular mass of this protein corresponds to the 28 kDa predicted for the product of gene 15 from its nucleotide sequence. The overproduced protein has been purified to near homogeneity and confirmed to be the product of gene 15 by amino acid sequence analysis of its N terminus. The purified product of gene 15 has a lysozyme activity similar to other phage-type lysozymes: products of phage T4 gene e and of phage P22 gene 19. However, to our knowledge phi 29 lysozyme is structurally unique among the phage-type lysozymes.

Amino Acid Sequence↗
PubMed1987

Analysis of somatosensory evoked potentials in peroneal nerve palsy.

The peroneal nerve SEPs over the CZ' of the scalp were studied in patients with peroneal nerve palsy. The initial positive peak latencies of P27 (to popliteal fossa stimulation), P30 (to fibular neck stimulation) and P37 (to dorsum of the foot stimulation) were measured. The latency difference P30-P27 was prolonged in all patients with the fibular head lesions. In patients with the superficial peroneal nerve lesions at the foreleg, P37-P27 was prolonged whereas P30-P27 was normal. Clinical application of peroneal nerve SEPs was useful in deciding the site of the lesion causing the peroneal nerve palsy.

Adult↗
PubMed1987

The genome of lipid-containing bacteriophage PRD1, which infects gram-negative bacteria, contains long, inverted terminal repeats.

The bacteriophage PRD1 is a lipid-bearing phage that infects a wide variety of gram-negative bacteria, including Escherichia coli and Salmonella typhimurium when they contain the appropriate plasmid. It contains a linear duplex DNA molecule that is covalently bound by its 5' ends to a terminal protein. We report here that the PRD1 genome contains a 111-base-pair terminal inverted repeat which does not bear homology to that of any known linear duplex DNAs with terminal proteins. We further report that its 3' termini are susceptible to enzymatic digestion by exonuclease III.

Bacteriophages↗
PubMed1987

A case of acute interstitial nephritis induced by flurbiprofen.

Recently, acute interstitial nephritis (AIN) presenting nephrotic syndrome and renal failure induced by nonsteroidal anti-inflammatory drug (NSAID) has been recognized with increasing frequency. We described here a 43-year-old woman who developed this type of nephropathy after taking NSAID for rheumatoid arthritis. Flurbiprofen (Froben) was assumed to be a causal drug based on a clinical course and a positive result of lymphocyte transformation test. Withdrawal of flurbiprofen therapy led no sufficient improvement, and high-dose steroid therapy done 15 months after the onset resulted in only a minor improvement. So far as we know, this was the second case of AIN associated with flurbiprofen and the youngest in NSAID-induced AIN with irreversible chronic renal insufficiency.

Acute Disease↗
PubMed1987

Effect of spergualin in autoimmune disease mice.

We investigated the effect of spergualin (SGL) upon the development of spontaneous systemic lupus erythematosus-like lesions in male MRL/MpJ-lpr/lpr mice. SGL was administered ip at doses of 2.5, 5 and 10 mg/kg to two groups of mice. One group received SGL prophylactically from 7 to 21 weeks of age. The other group received SGL curatively from 13 to 27 weeks of age. The occurrence of lupus lesions was characterized by enlarged lymphoid organs, high anti-DNA titer and blood urea nitrogen, and severe glomerular nephritis. In both groups these characteristics were significantly suppressed by SGL in a dose-dependent manner. This inhibitory activity was greatest at a dose of 10 mg/kg. These findings suggest that SGL has prophylactic and curative effects against lupus lesions in autoimmune disease in mice.

Animals↗