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Y Inouye

Publications and source records attributed to Y Inouye.

71 records · Page 4Linked to original sources
PubMed1986

Effects of streptonigrin derivatives and sakyomicin A on the respiration of isolated rat liver mitochondria.

Though all the streptonigrin derivatives with modifications in the carboxyl group on C2' were active as electron acceptors in the oxidation of NADH by Clostridium kluyveri diaphorase as well as streptonigrin, the glycine derivative did not show any marked effect on the KCN-insensitive oxidation of glutamate by rat liver mitochondria, suggesting a poor membrane transport of the glycine derivative. Sakyomicin A also induced the KCN-insensitive oxidation of glutamate by mitochondria, while a trace activity was observed by mitomycin C and the effect of doxorubicin was negligible. Like streptonigrin, the autoxidation of a reduced form (hydroquinone) of sakyomicin A to a quinone accompanied the generation of H2O2. However, exogenous NADH was oxidized by mitochondria in the presence of sakyomicin A but not streptonigrin.

Animals↗
PubMed1986

Role of the naphthoquinone moiety in the biological activities of sakyomicin A.

The naphthoquinone moiety was proven to be essential to the biological activities of sakyomicin A using various naphthoquinone derivatives. Among the naphthoquinones tested, juglone (5-hydroxy-1,4-naphthoquinone) which resembles the partial structure of sakyomicin A was the most active in cytotoxicity against murine lymphosarcoma L5178Y cells, electron acceptor function in the oxidation of NADH by Clostridium kluyveri diaphorase or rat liver mitochondria and inhibition against avian myeloblastosis virus reverse transcriptase. The significantly lower cytotoxicity of sakyomicin A as compared with juglone was attributable to its poor membrane transport. The inhibition of reverse transcriptase activity may result from the interaction between a sulfhydryl group in the active center of the enzyme and quinone groups of the naphthoquinones and sakyomicin A.

Animals↗
PubMed1986

Inhibition by sakyomicin A of avian myeloblastosis virus reverse transcriptase and proliferation of AIDS-associated virus (HTLV-III/LAV).

In the course of screening for inhibitors of reverse transcriptase, we have isolated an inhibitor from a strain of Nocardia and identified it as sakyomicin A. The antibiotic blocks avian myeloblastosis virus reverse transcriptase reaction: IC50 was ca. 30 micrograms/ml by the method employed. The drug affects proliferation of HTLV-III/LAV in HTLV-I-carrying MT-4 cells: ca. 60% inhibition was observed at an antibiotic concentration of 1.0 microgram/ml and ca. 20% inhibition at 0.1 microgram/ml, and there was no significant cytotoxicity.

Avian Leukosis Virus↗
PubMed1983

New Actinomyces and Streptococcus coaggregation groups among human oral isolates from the same site.

The coaggregation properties of recent human oral streptococcal and actinomyces isolates from the same site were determined and compared with the coaggregation properties of well-characterized stock strains of these two kinds of bacteria. Streptococcus sanguis, Actinomyces viscosus, Actinomyces naeslundii, and phenotypically similar strains of actinomyces were isolated from subgingival samples from periodontally healthy older individuals, from persons participating in an experimental gingivitis study, and from young persons with localized (juvenile) and generalized (severe) periodontitis. All 34 of the actinomyces isolates coaggregated with reagent strains of S. sanguis that represented the four streptococcal coaggregation groups. Most of these actinomyces exhibited coaggregations identical to those of actinomyces stock strains. However, five isolates of an Actinomyces WVa-963 serovar exhibited a coaggregation pattern different from any previously described, which was used to define coaggregation group F. All coaggregations with members of this group were lactose inhibitable. Only 57% (8 of 14) of the recent S. sanguis isolates coaggregated with actinomyces reagent strains. But when the nonreactive streptococcal isolates were tested for their ability to coaggregate with actinomyces from the same patient, a new, highly specific coaggregation pattern (group 6) for S. sanguis was discovered. Coaggregation of these streptococci was observed only with certain isolates of A. naeslundii (members of coaggregation group D) from the same site, and none of these coaggregations were inhibited by lactose. Subsequent testing revealed that streptococci of group 6 coaggregated with group D actinomyces from other sources but not with actinomyces of other coaggregation groups. Only two strains of S. sanguis failed to coaggregate with any strain of actinomyces tested. These results indicate that nearly all fresh isolates of these species obtained from both diseased and healthy sites exhibit specific, nonrandom patterns of coaggregation and suggest the widespread occurrence of in vivo cell-to-cell recognition between oral actinomyces and streptococci.

Actinomyces↗
PubMed1982

Anterior decompression for myelopathy resulting from ossification of the posterior longitudinal ligament.

In this series, 15 patients with ossification of the posterior longitudinal ligament underwent anterior decompression to relieve moderate or severe myelopathy, which in 11 included urinary disturbance. The operation consisted of partial resection of the vertebrae, release of the ossified plaque from the surrounding tissue and the insertion of an iliac bone graft. The extent of ossification was confirmed by computerised tomography before and after operation. The plaque was completely detached and moved forward in half of the patients, but only partially moved in the remainder. Symptoms improved considerably. Urinary disturbance disappeared in all patients, but sensory disturbance was left in most. Two patients had prolonged symptoms which were not relieved despite the complete release of the ossified defect.

Adult↗
PubMed1978

Conduction along the articular branch of the suprascapular nerve.

The maximum sensory conduction velocity was measured along the articular branch of the suprascapular nerve. The potential was evoked by stimulating in the perception area of the nerve above the glenohumeral joint and recorded by an electrode near the suprascapular nerve in the supraclavicular fossa. The maximum conduction velocity averaged 42 m/s, SD 4.6 m/s (20 normal subjects); it decreased slightly with age. When correcting for the error in distance arising from the measurement by obstetric calipers (20%), the maximum conduction velocity averaged 50 m/s. The peak-to-peak amplitude of the main component of the sensory potential was 0.8 muV, SD 0.5 muV. In one of seven patients with a pain syndrome in the shoulder secondary to a brachial plexus neuropathy the velocity and the amplitude of the sensory potential was diminished. In five other patients with pain in the region of the shoulder the conduction velocity was normal but the amplitude was diminished.

Adult↗
PubMedDate not supplied

Evanescent field excitation and measurement of dye fluorescence in a metallic probe near-field scanning optical microscope.

We introduce a method of dye fluorescence excitation and measurement that utilizes a near-field scanning optical microscope (NSOM). This NSOM uses an apertureless metallic probe, and an optical system that contains a high numerical aperture (NA) objective lens (NA= 1.4). When the area which satisfies NA < 1 is masked, the objective lens allows for the rejection of possible transmitted light (NA < 1) through the sample. In such conditions, the focused spot consists of only the evanescent field. We found that this NSOM system strongly reduces the background of the dye fluorescence and allows for the measurement of the fluorescence intensity below the diffraction limit of the excitation source.

Journal Article↗