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Akira Inoue

Publications and source records attributed to Akira Inoue.

51 records · Page 3Linked to original sources
PubMed2003

Organic solvent tolerance of halophilic archaea.

Organic solvent tolerance was tested in type strains of type species of the sixteen genera of Halobacteriaceae, the halophilic archaea. Most of the strains were observed to grow in the presence of hexylether (log Pow=5.1), but none grew in the presence of n-octane (log Pow=4.9) except Halogeometricum borinquense JCM 10706T and Halorubrum saccharovorum JCM 8865T. On the other hand, two strains, Haloarcula spp. OHF-1 and 2 isolated from a French solar salt were found to show stronger tolerance even to isooctane (log Pow=4.8). Growth of some strains was retarded by the presence of n-decane but reached to the same cell densities at late stationary phase. Final cell densities of some strains were greatly repressed by the presence of the solvent.

Alkanes↗
PubMed2003

Comparison of enzyme activities in plasma and leukocytes in dairy and beef cattle.

Concentrations of plasma glucose, immunoreactive insulin (IRI) and free fatty acid (FFA) and activities of enzymes related to energy metabolism and lactate dehydrogenase (LDH) isoenzyme pattern in plasma and leukocytes were investigated in lactating Holstein cows (dairy cattle) and fattening Japanese Black Wagyu x Holstein steers (beef cattle). IRI concentrations and LDH and malate dehydrogenase (MDH) activities in the plasma of beef cattle were significantly higher than those in dairy cattle. The cytosolic ratio of MDH/LDH activity in the leukocytes of beef cattle was significantly higher than that of dairy cattle. These findings might be associated with the different energy metabolism between dairy and beef cattle.

Animals↗
PubMed2002

Characterization of the motor activity of mammalian myosin VIIA.

Myosin VIIA was cloned from rat kidney, and the construct (M7IQ5) containing the motor domain, IQ domain, and the coiled-coil domain as well as the full-length myosin VIIA (M7full) was expressed. The M7IQ5 contained five calmodulins. Based upon native gel electrophoresis and gel filtration, it was found that M7IQ5 was single-headed, whereas M7full was two-headed, suggesting that the tail domain contributes to form the two-headed structure. M7IQ5 had Mg(2+)-ATPase activity that was markedly activated by actin with K(actin) of 33 microm and V(max) of 0.53 s(-1) head(-1). Myosin VIIA required an extremely high ATP concentration for ATPase activity, ATP-induced dissociation from actin, and in vitro actin-translocating activity. ADP markedly inhibited the actin-activated ATPase activity. ADP also significantly inhibited the ATP-induced dissociation of myosin VIIA from actin. Consistently, ADP decreased K(actin) of the actin-activated ATPase. ADP decreased the actin gliding velocity, although ADP did not stop the actin gliding even at high concentration. These results suggest that myosin VIIA has slow ATP binding or low affinity for ATP and relatively high affinity for ADP. The directionality of myosin VIIA was determined by using the polarity-marked dual fluorescence-labeled actin filaments. It was found that myosin VIIA is a plus-directed motor.

Actins↗
PubMed2002

DOC-2/DAB2 is the binding partner of myosin VI.

Myosin VI is a molecular motor that moves processively along actin filaments and is believed to play a role in cargo movement in cells. Here we found that DOC-2/DAB2, a signaling molecule inhibiting the Ras cascade, binds to myosin VI at the globular tail domain. DOC-2/DAB2 binds stoichiometrically to myosin VI with one molecule per one myosin VI heavy chain. The C-terminal 122 amino acid residues of DOC-2/DAB2, containing the Grb2 binding site, is identified to be critical for the binding to myosin VI. Actin gliding assay revealed that the binding of DOC-2/DAB2 to myosin VI can support the actin filament gliding by myosin VI, suggesting that it can function as a myosin VI anchoring molecule. The C-terminal domain but not the N-terminal domain of DOC-2/DAB2 functions as a myosin VI anchoring site. The present findings suggest that myosin VI plays a role in transporting DOC-2/DAB2, a Ras cascade signaling molecule, thus involved in Ras signaling pathways.

Actin Cytoskeleton↗
PubMed2002

Phase I trial of weekly docetaxel in elderly patients with non-small cell lung cancer.

Recent experience with weekly administration of docetaxel has demonstrated less myelotoxicity and suggested that this regimen holds promise for elderly patients at the high risk of myelosuppression. However, in this phase I trial of weekly docetaxel conducted only in elderly patients (70 years old or more) with non-small cell lung cancer (NSCLC), the toxicity profile was markedly different from that in previous reports. The dose-limiting toxicities were neutropenia, diarrhea and infection, all of which were observed at a dose of 30 mg/m(2)/week and the maximum-tolerated dose by protocol definition was 30 mg/m(2)/week. Although other hematological and non-hematological toxicities observed in this treatment were generally moderate and were well tolerated by elderly patients with NSCLC, the risk of myelosuppression still requires careful attention.

Age Factors↗
PubMed2002

Primary structure of myosin heavy chain from fast skeletal muscle of Chum salmon Oncorhynchus keta.

The nucleotide sequence of the cDNA encoding myosin heavy chain of chum salmon Oncorhynchus keta fast skeletal muscle was determined. The sequence consists of 5,994 bp, including 5,814 bp of translated region deducing an amino acid sequence of 1,937 residues. The deduced sequence showed 79% homology to that of rabbit fast skeletal myosin and 84-87% homology to those of fast skeletal myosins from walleye pollack, white croaker and carp. The putative binding-sites for ATP, actin and regulatory light-chains in the subfragment-1 region of the salmon myosin showed high homology with the fish myosins (78-100% homology). However, the Loop-1 and Loop-2 showed considerably low homology (31-60%). On the other hand, the deduced sequences of subfragment-2 (533 residues) and light meromyosin (564 residues) showed 88-93% homology to the corresponding regions of the fish myosins. It becomes obvious that several specific residues of the rabbit LMM are substituted to Gly in the salmon LMM as well as the other fish LMMs. This may be involved in the structural instability of the fish myosin tail region.

Animals↗
PubMed2002

Slug, a highly conserved zinc finger transcriptional repressor, protects hematopoietic progenitor cells from radiation-induced apoptosis in vivo.

We show here that a zinc finger transcriptional repressor, Slug, which is aberrantly upregulated by the E2A-HLF oncoprotein in pro-B cell acute leukemia, functions as an antiapoptotic factor in normal hematopoietic progenitor cells. Slug(-/-) mice were much more radiosensitive than wild-type mice, dying earlier and showing accentuated decreases in peripheral blood cell counts, as well as abundant microhemorrhages and widely disseminated bacterial microabscesses throughout the body. Slug expression was detected in diverse subsets of hematopoietic progenitors, but not in more differentiated B and T lymphoid cells, and there was a significant increase in apoptotic (TUNEL-positive) bone marrow progenitor cells in irradiated Slug(-/-) mice compared to wild-type controls. These results implicate Slug in a novel survival pathway that protects hematopoietic progenitors from apoptosis after DNA damage.

Animals↗
PubMed2002

Myosin IXb is a single-headed minus-end-directed processive motor.

Myosin is an actin-based molecular motor that constitutes a diverse superfamily. In contrast to conventional myosin, which binds to actin for only a short time during cross-bridge cycling, recent studies have demonstrated that class V myosin moves along actin filaments for a long distance without dissociating. This would make it suitable for supporting cargo movement in cells. Because myosin V has a two-headed structure with an expanded neck domain, it has been postulated to 'walk' along the 36-nm helical repeat of the actin filament, with one head attached to the actin and leading the other head to the neighbouring helical pitch. Here, we report that myosin IXb, a single-headed myosin, moves processively on actin filaments. Furthermore, we found that myosin IXb is a minus-end-directed motor. In addition to class VI myosin, this is the first myosin superfamily member identified that moves in the reverse direction. The processive movement of the single-headed myosin IXb cannot be explained by a 'hand-over-hand' mechanism. This suggests that an alternative mechanism must be operating for the processive movement of single-headed myosin IXb.

Actins↗
PubMed2002

Molecular phylogenetic analyses of reverse-transcribed bacterial rRNA obtained from deep-sea cold seep sediments.

A depth profile of naturally occurring bacterial community structures associated with the deep-sea cold seep push-core sediment in the Japan Trench at a depth of 5343 m were evaluated using molecular phylogenetic analyses of RNA reverse transcription-PCR (RT-PCR) amplified 16S crDNA fragments. A total of 137 clones of bacterial crDNA (complimentary rDNA) phylotypes (phylogenetic types) obtained at three different depths (2-4, 8-10 and 14-16 cm) were identified in partial crDNA sequencings. crDNA phylotypes from the cold seep sediment were dominantly composed of delta- and epsilon-Proteobacteria (36% and 42% respectively). Phylotype analysis of crDNA clone libraries and terminal restriction fragment length polymorphism (T-RFLP) analysis revealed that the majority of bacterial components shifted from delta- Proteobacteria to epsilon-Proteobacteria with increasing depth. Among the delta-proteobacterial crDNA clones, the sequences related to the genus Desulfosarcina were dominant. Almost all sequences of crDNA belonging to epsilon-Proteobacteria were affiliated with the same cluster (epsilon-CSG: epsilon-proteobacterial cold seep group), and were closely related with rDNA sequences from deep-sea hydrothermal vent environments.

Base Sequence↗
PubMed2002

Phase I/II study of 3-week cycle cisplatin-gemcitabine in advanced non-small cell lung cancer.

BACKGROUND: The combination of cisplatin and gemcitabine is one of the most active chemotherapy regimens against non-small cell lung cancer. However, the optimum schedule for this combination has not been determined. This study was performed to determine the maximum tolerated dose of gemcitabine combined with cisplatin in a 3-week cycle regimen and to observe safety and efficacy for Japanese patients with advanced non-small cell lung cancer. METHODS: 80 mg/m(2) of cisplatin on day 1 and escalated doses of gemcitabine on days 1 and 8 were administered every 3 weeks to patients with previously untreated, advanced non-small cell lung cancer. The initial dose of gemcitabine was 1000 mg/m(2) and was escalated in 250 mg/m(2) increments. RESULTS: Twenty-four patients were enrolled between March and December 2000. In total, 64 courses were given. The main toxicities were neutropenia, thrombocytopenia and hepatotoxicity. The maximum tolerated dose was determined to be 1500 mg/m(2) of gemcitabine combined with 80 mg/m(2 )of cisplatin. Nine of 24 patients (37.5%) achieved a partial response. CONCLUSION: This study demonstrates that the combination of cisplatin and gemcitabine repeated every three weeks is tolerable for Japanese patients with advanced non-small cell lung cancer. We determined 1250 mg/m(2) of gemcitabine combined with 80 mg/m(2 )of cisplatin to be the recommended dose.

Adult↗
PubMed2002

Methanothermococcus okinawensis sp. nov., a thermophilic, methane-producing archaeon isolated from a Western Pacific deep-sea hydrothermal vent system.

A novel thermophilic, methane-producing archaeon was isolated from a deep-sea hydrothermal vent chimney at the Iheya Ridge, in the Okinawa Trough, Japan. The cells were highly motile, irregular cocci, with a polar bundle of flagella. Growth was observed between 40 and 75 degrees C (optimum 60-65 degrees C; 30 min doubling time) and between pH 4.5 and 8.5 (optimum pH 6.7). The isolate was a strictly anaerobic autotroph capable of using hydrogen and carbon dioxide as sole sources of energy and carbon. Formate can serve as an alternative energy source. The G+C content of the genomic DNA was 33.5 mol%. Phylogenetic analysis based on 16S rDNA sequences and DNA-DNA hybridization analysis indicated that the isolate was closely related to members of the genera Methanococcus and Methanothermococcus. This isolate, however, could be differentiated from the previously described species of these genera on the basis of its physiological and molecular properties. The name Methanothermococcus okinawensis sp. nov is proposed, with the type strain IH1T (=JCM 11175T=DSM 14208T).

DNA, Ribosomal↗
PubMed2002

Inhibition of proteasome activity is involved in cobalt-induced apoptosis of human alveolar macrophages.

Inhalation of particulate cobalt has been known to induce interstitial lung disease. There is growing evidence that apoptosis plays a crucial role in physiological and pathological settings and that the ubiquitin-proteasome system is involved in the regulation of apoptosis. Cadmium, the same transitional heavy metal as cobalt, has been reported to accumulate ubiquitinated proteins in neuronal cells. On the basis of these findings, we hypothesized that cobalt would induce apoptosis in the lung by disturbance of the ubiquitin-proteasome pathway. To evaluate this, we exposed U-937 cells and human alveolar macrophages (AMs) to cobalt chloride (CoCl(2)) and examined their apoptosis by DNA fragmentation assay, 4',6-diamidino-2'-phenylindol dihydrochloride staining, and Western blot analysis. CoCl(2) induced apoptosis and accumulated ubiquitinated proteins. Exposure to CoCl(2) inhibited proteasome activity in U-937 cells. Cobalt-induced apoptosis was mediated via mitochondrial pathway because CoCl(2) released cytochrome c from mitochondria. These results suggest that cobalt-induced apoptosis of AMs may be one of the mechanisms for cobalt-induced lung injury and that the accumulation of ubiquitinated proteins might be involved in this apoptotic process.

Antimutagenic Agents↗
PubMed2002

[A case of chronic thromboembolic pulmonary hypertension based on essential thrombocythemia].

We report a case of chronic thromboembolic pulmonary hypertension based on essential thrombocythemia. A 72-year-old woman was admitted to our hospital with dyspnea. The hematologic workup revealed a platelet count of 99.2 x 10(4)/microliter. Chest radiographic examination revealed cardiomegaly with bilateral pulmonary artery enlargement. A perfusion lung scan suggested and pulmonary angiography confirmed--multiple pulmonary embolism. Pulmonary artery pressure was 90/30 (51) mmHg. Thrombolytic therapy was performed successfully, and a diagnosis of essential thrombocythemia was made on the basis of the criteria proposed by the Polycythemia Vera Study Group. The therapy of essential thrombocythemia including ranimustine was effective, and one year later, the essential thrombocythemia and chronic respiratory failure had improved. To our knowledge, this case of chronic thromboembolic pulmonary hypertension based on essential thrombocythemia is a very rare one.

Aged↗
PubMedDate not supplied

Acute Korsakoff syndrome following mammillothalamic tract infarction.

There are limited case reports of structural lesions causing Korsakoff syndrome. This report describes acute Korsakoff syndrome following localized, bilateral infarction of the mammillothalamic tracts (MTTs). Axial T2-weighted imaging revealed the lesions at the lateral wall level of the third ventricle and diffusion-weighted imaging confirmed that the left lesion was new and the right old. Korsakoff syndrome persisted 6 months after the onset. This case suggests that bilateral MTT dysfunction can lead to Korsakoff syndrome.

Acute Disease↗