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Masao Inoue

Publications and source records attributed to Masao Inoue.

12 recordsLinked to original sources
PubMed2026

Carbon monoxide-driven proton respiration enables facultative anaerobes to survive electron acceptor limitation.

Diverse microorganisms couple the oxidation of carbon monoxide gas (CO) to the reduction of protons, producing hydrogen gas (H2) using nickel-containing CO dehydrogenase/energy-converting hydrogenase (Ni-CODH/ECH). Although this process yields one of the lowest free-energy gains in biology, its physiological role at environmentally relevant CO levels remains unresolved. Here, we show that Ni-CODH/ECH functions as a survival-oriented energy conservation system that enables heterotrophic facultative anaerobes to survive electron acceptor limitation, rather than primarily supporting growth or CO detoxification. Analysis of 387 genomes of Anoxybacillaceae species revealed that Ni-CODH/ECH had a patchy distribution and, with one exception, was mutually exclusive with the oxygen-tolerant molybdenum-containing CODH, suggesting ecological specialization. Culture experiments using three isolates (Parageobacillus sp. G301, P. thermoglucosidasius NBRC 107763, and Thermolongibacillus altinsuensis B1-1) demonstrated that CO-dependent proton respiration is activated during stationary phase when exogenous electron acceptors are limiting, maintaining cell density under 25% CO, whereas no effect was observed in a Ni-CODH knockout (ΔcooCSF) strain. RNA-seq analysis of Parageobacillus sp. G301 under twelve conditions revealed that Ni-CODH/ECH genes are highly expressed (top 0.2%-1.9% of all genes) under electron acceptor-free conditions, independent of CO presence, under the predicted control of the redox-dependent transcriptional repressor Rex. ΔcooCSF cultures accumulated more CO than the wild-type (WT), suggesting trace CO scavenging by the WT. Together, our results redefine Ni-CODH/ECH as a redox-regulated auxiliary energy-conservation strategy that supports survival and maintenance in anaerobic energy-limited environments using two ubiquitous substrates. This work extends the carboxydovore paradigm of trace gas-based survival from aerobic to spatiotemporally variable anaerobic environments.

Carbon Monoxide↗
PubMed2006

Modified intrapleural cisplatin treatment for lung cancer with positive pleural lavage cytology or malignant effusion.

OBJECTIVES: We evaluate the efficacy and safety of the modified intrapleural cisplatin treatment for lung cancer patients with positive pleural lavage cytology or malignant effusion. METHODS: The treatment was performed for seven patients with malignant effusion and 18 patents with positive pleural lavage cytology. After pulmonary resection, the pleural cavity was filled with cisplatin with a normal saline solution for 30 min. Complications and survival of the patients were evaluated. RESULTS: The chest tube duration were significantly prolonged in the treatment (CDDP) group (5.7 +/- 3.6 vs. 2.8 +/- 2.6 days). We had one operative death that developed a bronchial fistula; however, the other complications were not severe. The mortality rate was 4% and the morbidity rate was 60%. We experienced two carcinomatous pleuritis in the CDDP group. The median survival time of the CDDP group was 47.0 +/- 11.1 months and the 3- and 5-year survival rate was 52.6% and 11.3%, respectively. CONCLUSIONS: We were able to perform this treatment for these advanced lung cancer patients, which had the preventive effect of carcinomatous pleuritis. This therapy shows the possibility of a treatment that might lead to an improvement in the prognosis of these patients, without causing severe complications.

Aged↗
PubMed2005

Transcription-independent suppression of DNA synthesis by p53 in sperm-irradiated mouse zygotes.

Cell cycle arrest in response to DNA damage is important for the maintenance of genomic integrity in higher eukaryotes. We have previously reported the novel p53-dependent S-phase checkpoint operating in mouse zygotes fertilized with irradiated sperm. In the present study, we analysed the detail of the p53 function required for this S-phase checkpoint in mouse zygotes. The results indicate that ATM kinase is likely to be indispensable for the p53-dependent S-phase checkpoint since the suppression was abrogated by inhibitors such as caffeine and wortmannin. However, ATM phosphorylation site mutant proteins were still capable of suppressing DNA synthesis when microinjected into sperm-irradiated zygotes lacking the functional p53, suggesting that the target of the phosphorylation is not p53. In addition, the suppression was not affected by alpha-amanitin, and p53 protein mutated at the transcriptional activation domain was also functional in the suppression of DNA synthesis. However, p53 proteins mutated at the DNA-binding domain were devoid of the suppressing activity. Taken together, the transcription-independent function of p53 associated with the DNA-binding domain is involved in the S-phase checkpoint in collaboration with yet another unidentified target protein(s).

Alleles↗
PubMed2005

Surgical treatment for lung cancer in octogenarians.

PURPOSE: We conducted this study in order to determine how we should perform the surgical treatment for clinical stage I non-small cell lung cancer (NSCLC) in octogenarians. METHODS: Thirty-three octogenarians with clinical stage I NSCLC participated in this study. They were retrospectively divided into two groups: one group of 11 patients who underwent a lymph node dissection (ND group), and one group of 22 patients who did not undergo this procedure (ND0 group). We analyzed the surgical invasiveness, morbidity, mortality, and survival in both groups. RESULTS: The morbidity rate in the ND group (45%) was higher than that in the ND0 group (23%); however, the difference was no statistically significant (P = 0.1805). There was no significant difference in the overall survival rates of the two groups (P = 0.1647), and the median survival time of the ND0 group (76 months) was slightly longer than that of the ND group (26 months). There was no significant difference in local recurrence rate between the two groups (9.1% vs 4.5%, P = 0.6059). CONCLUSION: We thus conclude that a limited operation without lymph node dissection might be the best surgical treatment for carefully selected octogenarians with clinical stage I NSCLC.

Aged, 80 and over↗
PubMed2005

Pulmonary tractotomy for a patient with traumatic penetrating lung injury: report of a case.

We report a case of traumatic hemopneumothorax caused by penetrating lung injury in a 26-year-old man. The patient underwent emergency thoractomy, which revealed hemorrhage in the lingular segment of the left lung. We found the bleeding point and controlled the hemorrhage using pulmonary tractotomy by inserting a linear stapler into the stab wound in the pulmonary parenchyma. The original technique of pulmonary tractotomy was performed for complete through-and-through injury by dividing the bridge of lung tissue between the aortic clamps. We were able to apply this procedure safely to stop bleeding from a stab wound that did not go through the lung. Thus, pulmonary tractotomy is an effective damage-control operation for the lung with obvious advantages over major lung resection.

Adult↗
PubMed2004

Inhaled nitric oxide attenuates apoptosis in ischemia-reperfusion injury of the rabbit lung.

BACKGROUND: Lung ischemia-reperfusion injury occurs after lung transplantation and various clinical procedures. Recently, apoptosis was reported to be induced after ischemia-reperfusion. We investigated the effects of inhaled nitric oxide (NO) on lung ischemia-reperfusion and apoptosis after ischemia-reperfusion. METHODS: As a control group, the left pulmonary hilum of Japanese white rabbits (n = 10) was occluded for 120 minutes and reperfused for 120 minutes. In the inhaled NO group (n = 10), 20 parts per million nitric oxide was inhaled during reperfusion. The sham-operated group was ligated at the right hilum and perfused by the left lung only for 120 minutes. The mean pulmonary arterial pressures and Pao2 were measured during reperfusion. The wet-to-dry weight ratio of the left lower lobe of the lung was calculated. The number of apoptotic cells was estimated using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) technique. The TUNEL staining for a time course study was done using 15 control animals that were killed by exsanguination at 15, 30, and 60 minutes after reperfusion. RESULTS: After 120 minutes of reperfusion, the mean pulmonary arterial pressures in the control group and in the inhaled NO group were 23.0 +/- 3.2 mm Hg and 13.6 +/- 2.4 mm Hg, respectively (p < 0.01). At the same time point, the Pao2 in the control group and in the inhaled NO group were 46.1 +/- 15.9 mm Hg and 88.1 +/- 14.7 mm Hg, respectively (p < 0.01). The wet-to-dry weight ratios in the control group and in the inhaled NO group were 0.856 +/- 0.024 and 0.808 +/- 0.006, respectively (p < 0.01). Apoptotic cells appeared in the early phase of reperfusion (after 15 minutes' reperfusion). The number of apoptotic cells was significantly lower in the inhaled group than in the control group after 120 minutes' reperfusion (1.76% versus 2.87%, p < 0.01). CONCLUSIONS: Our results suggest that the inhaled NO prevents lung ischemia-reperfusion injury and attenuates apoptosis after reperfusion in the rabbit lung.

Administration, Inhalation↗
PubMed2003

Preoperative irradiation combined with chemotherapy impairs healing of bronchial anastomosis during the early postoperative period in rats.

The effect of preoperative irradiation and antineoplastic agents on healing at the site of bronchial anastomosis was investigated using rats. The bursting pressure in irradiation group and combined irradiation and chemotherapy group was significantly lower than in control and chemotherapy group at day 5 after operation. There was no significant difference in bursting pressure in all groups at day 7. The histologic finding of the anastomosis with H & E stain showed that submucosal connective tissue had not regenerated, and defects were seen in the submucosal tissue in irradiation and combined therapy group at day 3 and day 5. But, the connective tissue had matured in irradiation group at day 7 compared with control group. In conclusion, this study demonstrated that the healing of bronchial anastomosis was markedly delayed in early postoperative days in the rats receiving irradiation and combined therapy.

Anastomosis, Surgical↗
PubMed2002

2,3,7,8-Tetrachlorodibenzo-p-dioxin is a possible activator of human cytomegalovirus replication in a human fibroblast cell line.

We examined the effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on human cytomegalovirus (CMV) replication in the human embryonic fibroblast cell line, MRC-5. Treatment of cells with 0.0001pg/ml TCDD augmented the cytopathic effects of CMV-infected MRC-5 cells. Moreover, TCDD increased the replication of intracellular CMV without affecting the proliferation of host cells, with a concomitant increase in CMV UL54 DNA levels. However, TCDD demonstrated no virocidal effect on cell-free CMV. Furthermore, CMV-infected MRC-5 cells expressed transcripts of the aryl hydrocarbon receptor (AhR) and AhR nuclear translocator. These results suggest that TCDD may contribute to the development of opportunistic diseases by reactivation of latently infected CMV and that TCDD regulates CMV replication through the dependence on AhR.

Cell Line↗
PubMed2002

p53-dependent S-phase damage checkpoint and pronuclear cross talk in mouse zygotes with X-irradiated sperm.

One difficulty in analyzing the damage response is that the effect of damage itself and that of cellular response are hard to distinguish in irradiated cells. In mouse zygotes, damage can be introduced by irradiated sperm, while damage response can be studied in the unirradiated maternal pronucleus. We have analyzed the p53-dependent damage responses in irradiated-sperm mouse zygotes and found that a p53-responsive reporter was efficiently activated in the female pronucleus. [(3)H]thymidine labeling experiments indicated that irradiated-sperm zygotes were devoid of G(1)/S arrest, but pronuclear DNA synthesis was suppressed equally in male and female pronuclei. p53(-/-) zygotes lacked this suppression, which was corrected by microinjection of glutathione S-transferase-p53 fusion protein. In contrast, p21(-/-) zygotes exhibited the same level of suppression upon fertilization by irradiated sperm. About a half of the 6-Gy-irradiated-sperm zygotes managed to synthesize a full DNA content by prolonging S phase, while the other half failed to do so. Regardless of the DNA content, all the zygotes cleaved to become two-cell-stage embryos. These results revealed the presence of p53-dependent pronuclear cross talk and a novel function of p53 in the S-phase DNA damage checkpoint of mouse zygotes.

Animals↗
PubMed2002

The novel surveillance mechanism of the Trp53-dependent s-phase checkpoint ensures chromosome damage repair and preimplantation-stage development of mouse embryos fertilized with x-irradiated sperm.

Cell cycle checkpoints and apoptosis function as surveillance mechanisms in somatic tissues. However, some of these mechanisms are lacking or are restricted during the preimplantation stage. Previously, we reported the presence of a novel Trp53-dependent S-phase checkpoint that suppresses pronuclear DNA synthesis in mouse zygotes fertilized with X-irradiated sperm (sperm-irradiated zygotes) (Shimura et al., Mol. Cell. Biol. 22, 2220-2228, 2002). Here we studied the role of the Trp53-dependent S-phase checkpoint in the early stage of development of sperm-irradiated zygotes. In the Trp53(+/+) genetic background, all of the sperm-irradiated zygotes cleaved successfully to the two-cell stage despite the fact that half of them carried a sub-2N amount of DNA. These zygotes progressed normally to the eight-cell stage and then implanted, but the subsequent fetal development was suppressed in a dose-dependent manner. In contrast, sperm-irradiated Trp53(-/-) embryos lacking an S-phase checkpoint exhibited an abnormal segregation of chromosomes at the first cleavage, even though they carried an apparently normal 2N amount of DNA. They were morphologically abnormal with numerous micronuclei, and they degenerated before reaching the eight-cell stage. As a consequence, no implants were observed for sperm-irradiated Trp53(-/-) embryos. These results suggest that the Trp53-dependent S-phase checkpoint is a surveillance mechanism involved in the repair of chromosome damage and ensures the preimplantation-stage development of sperm-irradiated embryos.

Animals↗
PubMedDate not supplied

Graft copolymerization of methyl methacrylate onto mercaptochitin and some properties of the resulting hybrid materials.

The graft copolymerization of methyl methacrylate onto mercaptochitin and some properties of the resulting graft copolymers have been studied. Methyl methacrylate was efficiently graft copolymerized onto mercaptochitin in dimethyl sulfoxide, and the grafting percentage reached 1300% under appropriate conditions. Although the side-chain ester groups were resistant to aqueous alkali, hydrolysis could be achieved with a mixture of aqueous sodium hydroxide and dimethyl sulfoxide. Subsequent treatment with acetic anhydride in methanol transformed the sodium carboxylate groups into carboxyl groups. Although the graft copolymers exhibited an improved affinity for organic solvents, those having sodium carboxylate or carboxyl units were characterized by a much more enhanced solubility and were soluble in common solvents. The hygroscopic nature of chitin decreased with an increase in the grafting extent but increased significantly upon hydrolysis of the ester groups. The enzymatic degradability of the graft copolymers, as evaluated with lysozyme, was also dependent on the grafting extent and much higher than that of the original chitin. DSC measurements revealed the presence of a glass transition phenomenon, which could be ascribed to the poly(methyl methacrylate) side chain.

Animals↗