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Y Takaki

Publications and source records attributed to Y Takaki.

At least 37 records · Page 2Linked to original sources
PubMed1999

Genetic analysis of the chromosome of alkaliphilic Bacillus halodurans C-125.

Seventeen Sse8387I linking clones isolated from the chromosome of Bacillus halodurans C-125 for the purpose of constructing a physical map were sequenced and analyzed by comparison with the BSORF database and the nonredundant protein databank. The orientations of Sse8387I or AscI linking clones serving to join adjacent fragments were determined by southern blot analysis using specific DNA probes. One-third of the open reading frames (ORFs) identified in the Sse8387I linking clones showed no significant similarity to any protein so far reported. The ORFs showing significant similarities to those of Bacillus subtilis were mapped in the chromosome of strain C-125, and the locations of the putative genes on the map were not well conserved between B. halodurans C-125 and B. subtilis.

Bacillus↗
PubMed1999

Second-line chemotherapy with weekly cisplatin and irinotecan in patients with refractory lung cancer.

Cisplatin and irinotecan are reported to act synergistically. The authors have conducted a phase II trial combining cisplatin and irinotecan in patients with refractory lung cancer to evaluate the activity and safety of the regimen. Twenty-one patients, who had not responded to prior platinum-based chemotherapy, were entered into the study. Both cisplatin (30 mg/m2) and irinotecan (60 mg/m2) were administrated on days 1, 8, and 15, and the regimen was repeated every 28 days. There were six partial responses, and the response rate was 29% (95% confidence interval, 11.3%-52.2%). The median survival time of all patients was 32 weeks, and 1-year and 2-year survival rates were 43% and 11%, respectively. Major toxicities were hematologic; leukopenia of grades 3 and 4 developed in 43% patients, anemia developed in 38%, and thrombocytopenia developed in 19%. One notable nonhematologic toxicity was diarrhea; which was grade 3 in 38%. The weekly chemotherapy combining cisplatin and irinotecan was active against lung cancer, which is refractory to platinum-based chemotherapy. However, skips of drug administration or dose reduction were necessary in 76% patients during two courses of planned administration, though the ratio of actual dose to scheduled dose was 81%. Dose modification would be necessary to yield better results by this weekly chemotherapy.

Adult↗
PubMed1999

Sequence analysis of a 32-kb region including the major ribosomal protein gene clusters from alkaliphilic Bacillus sp. strain C-125.

Forty-one open reading frames (ORFs) were identified in a 32-kb DNA fragment of alkaliphilic Bacillus sp. C-125. A similarity search using the BSORF database found 37 ORFs with significant sequence similarity to B. subtilis RNA polymerase subunits, elongation factor G, elongation factor Tu, and ribosomal proteins. Each ORF product showed more than 70% identity to those of B. subtilis. Gene organization in the region of str, S10, spc, and the alpha cluster was highly conserved among three strains, C-125, B. subtilis, and B. stearothermophilus.

Bacillus↗
PubMed1999

[Effect of PCBs on mouse lung tumorigenesis induced by 1-nitropyrene: a preliminary report].

We have analyzed the effect of polychlorinated biphenyls (PCB, Kanechlor-400) on 1-nitropyrene (1-NP) induced lung tumor. Male A/J mice (6 weeks old) were used for the experiment. A total of 2.5 mg/kg PCB was administered intraperitoneally (PCB group), a total of 0.38 mmol/kg 1-NP was administered intraperitoneally for 17 times (1-NP group), PCB was administered followed by i.p. injection of 1-NP (PCB + 1-NP group), and only vehicle was administered (control group). The lung lesions induced were examined 18 weeks after the final treatment with 1-NP or vehicle. In control group, no neoplastic lesion in the lung was induced. In PCB group, only one lesion with adenoma was induced. In 1-NP group, various kinds of lung neoplastic lesions including hyperplasia, adenoma and adenocarcinoma were induced. In PCB + 1-NP group, both the number and size of tumors induced were significantly more than those in 1-NP group. In addition, the number of adenocarcinoma formed was more in PCB + 1-NP group than in 1-NP group. Each lesion was microdissected to collect and analyze DNA of the targeted tissue. K-ras gene mutation was detected in part of adenoma lesions and all the carcinoma lesions. The mutation was found in either 1-NP or PCB + 1-NP group, but not in control and PCB group. The pattern of K-ras mutation was CAA to CGA in codon 61 or GGT to GAT in codon 12. There was no difference in the pattern of K-ras mutation despite of the pretreatment with PCB. Although the present data are from small sample size, it was suggested that PCB may promote (but not initiate) 1-NP induced lung tumorigenesis, and may not induce K-ras mutation directly in the experimental system.

Adenocarcinoma↗
PubMed1998

Cloning and expression of the gene encoding RNA polymerase alpha subunit from alkaliphilic Bacillus sp. strain C-125.

The rpoA gene, encoding the alpha subunit of RNA polymerase, was isolated from alkaliphilic Bacillus sp. strain C-125 by the PCR method. A 3-kb HindIII fragment containing the complete rpoA gene was cloned and sequenced. The alpha subunit gene was found to encode a protein consisting of 314 amino acid residues with a molecular mass of 34,805 Da. Compared with the amino acid sequences of other known eubacterial RNA polymerase alpha subunits, the gene has 84% identity to that of B. subtilis, while showing 48% and 47% identity to that of Streptomyces coelicolor and Escherichia coli, respectively. Six conserved regions, which are observed in the case of other eubacteria, were found in the RNA polymerase alpha subunit of this strain. Five of them are located in the N-terminal domain involved in assembly of the core enzyme, while one is located in the C-terminal domain, which interacts with several transcriptional factors and a specific DNA element. By means of recombinant plasmids, a hexahistidine-tagged derivative of the RNA polymerase alpha subunit of strain C-125 and two deletion derivatives (C- and N-terminal domains) of this protein were overexpressed in E. coli cells and purified to near homogeneity.

Amino Acid Sequence↗
PubMed1998

Characterization of alpha-maltotetraohydrolase produced by Pseudomonas sp. MS300 isolated from the deepest site of the mariana trench.

We have isolated a Pseudomonas-like amylase producer, the strain MS300, which displayed a large halo on starch medium, from the deepest site of the Mariana Trench. The strain MS300 produced two major and two minor alpha-maltotetraohydrolases (G4-amylase). The two major G4-amylases share the same molecular weight of 55,000 but had different pI values, 5.0 and 4.7, respectively. The optimum temperature for activity of both major G4-amylases is 40 degrees C, and the optimum pH is 6.8 for one and 8.9 for the other. MS300 produced more amylase under high hydrostatic pressure than under atmospheric pressure. Strain MS300 may be active in the deep sea at a depth of 10,897 m.

Amino Acid Sequence↗
PubMed1998

Sudden unexpected death from pulmonary thromboembolism--examination of antemortem chest X-ray.

An autopsy case of a woman who died suddenly from undiagnosed and untreated pulmonary thromboembolism (PTE) on her way home from the hospital is described in this report. She had complained of chest pain and dyspnea on exertion when she visited the hospital and a chest X-ray taken at that time showed remarkable manifestation of right heart failure and PTE, compared with former X-rays taken during previous visits to the hospital. In this report we present the findings of four chest X-rays of this patient, which had been taken both before and after the development of PTE.

Chest Pain↗
PubMed1997

A peptidyl-prolyl cis/trans-isomerase (cyclophilin G) in regulated secretory granules.

A 27-kDa protein (p27) in horseshoe crab hemocyte that cross-reacts with antiserum against a beta-glucan-sensitive protease zymogen was purified to homogeneity, and its cDNA was cloned. The 1.7-kilobase pair cDNA contains an open reading frame of 660 base pairs, encoding a 23-amino acid signal sequence followed by a mature protein of 197 residues. The sequence of p27 exhibits strong similarity to that of cyclophilin B, a peptidyl-prolyl cis/trans-isomerase. p27 exhibits isomerase activity with a kcat/Km of 0.18 microM-1 s-1 for a peptide substrate; this activity is inhibited by cyclosporin A but is not affected by FK506. Although the p27 precursor possesses an amino-terminal secretory hydrophobic signal sequence, unlike other cyclophilin B molecules, it lacks a conserved carboxyl-terminal endoplasmic reticulum retention signal and it contains a central 8-amino acid insertion. Although p27 is secreted into the culture media of transiently expressed COS cells, it is not detected in horseshoe crab hemolymph plasma but rather is localized to the hemocyte large granules, the regulated secretory granules that are exocytosed upon stimulation. These results indicate that p27 is a new peptidyl-prolyl cis/trans-isomerase in the regulated secretory granules, and is thus designated cyclophilin G. This first report of a cyclophilin homologue in the secretory granule of the horseshoe crab hemocyte suggests that such chaperon-like proteins may constitute a key quality control system for stored proteins in exocytotic granules.

Amino Acid Sequence↗
PubMed1997

[An old female case of vero-cytotoxin-producing Escherichia coli O-157: H7 infection].

It is well known that verocytotoxin-producing Escherichia coli O-157 : H7 infection can be severe in elderly persons. We report an 82-year-old female case of verocytotoxin-producing Escherichia coli O-157 : H7 infection. She was admitted to our hospital because of bloody diarrhea. The hemolytic-uremic syndrome (HUS) was not occurred, but systemic edema, ascites, pleural effusion and pulmonary edema with hypoxyemia gradually appeared. Treatment with human immunoglobulin in addition to fluid therapy, antibiotics, diuretics and human serum albumin resulted in dramatic improvement. Management of complications such as sepsis and electrolyte disturbance caused by this infection was considered to be important in elderly patients.

Aged↗
PubMed1997

Beclomethasone dipropionate administration via cecostomy in ulcerative colitis.

Beclomethasone dipropionate was administered via a cecostomy to four patients with active ulcerative colitis that was refractory to conventional glucocorticosteroid therapy. From a tube cecostomy, beclomethasone dipropionate solution was administered continuously throughout the day. Clinical manifestations, laboratory examinations, and endoscopic and/or radiographic findings markedly improved within 1-2 wk. A serial decrease in the index of disease activity was observed from the time administration began (mean score, 226.0) to 2 wk later (137.4 points). An excellent clinical response was recognized without any significant side effects, and the urgent need for total colectomy was avoided in all four patients.

Adult↗
PubMed1996

Quantitative renography with the organ volume method and interporative background subtraction technique.

When quantification of renal activity is performed by planar imaging, many correction factors must be considered. To obtain quantitative renal images and renogram, we have examined our proposed method by using the organ volume for scatter, attenuation, and background activity, and the interporative background subtraction (IBS) technique in phantom and clinical studies. A renal phantom study was performed by varying the renal depth from 3 to 11 cm and the kidney-to-background activity concentration ratio from 5 to 80. Planar images were properly corrected for scatter, attenuation and background activity by our method and the corrected images were compared with the images obtained by the conventional method for the estimation of true renal activity. Clinical Tc-99m DTPA dynamic data for both a good and a poor renal function were also corrected by our method and volume-corrected renograms were obtained. For the phantom study, depth-independent images were obtained and these images gave a good estimation of the true count rate. In the clinical study, the conventional renogram was especially modified to allow for oversubtraction of background counts in the early phase (0-4 min). In conclusion, our proposed correction method can assess renal function qualitatively and quantitatively in both static and dynamic planar renal imaging.

Evaluation Studies as Topic↗
PubMed1996

Chronic Prototheca meningitis.

A case of chronic meningitis caused by the achloric alga Prototheca wickerhamii is described, which has persisted for more than 6 years despite treatment with various antifungal agents. For the last year no treatment has been given, but the patient has no complaints.

Adult↗
PubMed1996

[A case of report of traumatic aortic regurgitation accompanying cerebral embolism].

Aortic regurgitation due to nonpenetrating trauma of the chest is an extremely rare disease and only 12 cases have been reported in this country. We report a case we treated and present additional of retrospective discussions. The patient was a 59-year-old man who lost consciousness due to a heavy blow to the chest during work. He was diagnosed as having acute aortic regurgitation. A close examination on the 3rd day after the injury revealed cerebral embolism and heart failure could not be controlled by physical treatment. Surgery was performed on the 5th day after the injury. The aorta was incised under cardiopulmonary bypass to examine aortic valves. Commissures between the RCC and the NCC and between the NCC and the LCC had been torn from the aortic wall and injured and thrombus adhesion was observed in a part of the NCC. After repairing the aortic wall, the valve was replaced by SJM valve. Postoperative course is satisfactory.

Aortic Valve↗
PubMed1995

Purified horseshoe crab factor G. Reconstitution and characterization of the (1-->3)-beta-D-glucan-sensitive serine protease cascade.

Horseshoe crab hemocyte lysate responds to (1-->3)-beta-D-glucans, initiating an enzymatic cascade, which culuminates in clot formation. We have purified to homogeneity the serine protease zymogen factor G, which is directly activated by (1-->3)-beta-D-glucans and which initiates the hemolymph clotting cascade. Factor G is a heterodimeric protein composed of two noncovalently associated subunits alpha (72 kDa) and beta (37 kDa). In the presence of (1-->3)-beta-D-glucans such as curdlan and paramylon, factor G is autocatalytically activated to an active serine protease named factor G. This activation is accompanied by limited proteolysis of both subunits: the 72-kDa subunit alpha is cleaved to 55-kDa and 17-kDa fragments, and the 37-kDa subunit beta is shortened to 34 kDa. Longer incubations with (1-->3)-beta-D-glucans result in cleavage of the 55-kDa fragment to 46 kDa and the 34-kDa fragment to 32 kDa, with concomitant loss of amidase activity. Reconstitution experiments using purified proteins participating in the hemolymph clotting cascade demonstrate that factor G is capable of activating proclotting enzyme directly, resulting in the conversion of coagulogen to coagulin gel. Thus, purified factor G is shown to be the primary initiator of the (1-->3)-beta-D-glucan-sensitive coagulation pathway in the horseshoe crab hemocyte lysate.

Amino Acid Sequence↗
PubMed1995

Generation mechanism and purification of an inactive form convertible in vivo to the active form of quinoprotein alcohol dehydrogenase in Gluconobacter suboxydans.

Alcohol dehydrogenase (ADH) of acetic acid bacteria is a membrane-bound quinohemoprotein-cytochrome c complex involved in vinegar production. In Gluconobacter suboxydans grown under acidic growth conditions, it was found that ADH content in the membranes was largely increased but the activity was not much changed, suggesting that such a condition produces an inactive form of ADH (inactive ADH). A similar phenomenon could be also observed in Acetobacter aceti, another genus of acetic acid bacteria. Furthermore, aeration conditions were also shown to affect ADH production; the ADH level was increased and was present as an active form under low-aeration conditions, while the ADH level was decreased and was present mainly as an inactive form under high-aeration conditions. Inactive ADH was solubilized from the membranes of G. suboxydans grown in acidic and high-aeration conditions and was purified separately from the normal, active form of ADH (active ADH). In spite of having 10 times less enzyme activity than active ADH, inactive ADH could not be distinguished from active ADH with respect to their subunit compositions, molecular sizes, and prosthetic groups. Inactive ADH, however, had a relatively loose conformation with a partially oxidized state, while active ADH had a tight conformation with a completely reduced state, suggesting that inactive ADH may lack a right subunit's interaction and that one of the heme c components may be inactivated. Reactivation from such an inactive ADH occurred either by shifting of the pH of the culture medium up during the cultivation or by incubation of the resting cells at the neutral pH region in the presence of an energy source such as D-sorbitol. Such an activation of ADH was repressed by the addition of a proton uncoupler and could not occur in the spheroplasts. Thus, the results suggest that inactive ADH could be generated abundantly under acidic growth conditions and converted to the active form at a neutral culture pH. The data also suggest that some periplasmic component may be involved in the conversion of inactive ADH into the active form by consuming some forms of energy.

Acetobacteraceae↗
PubMed1995

[Changes in intraoperative and postoperative colloid oncotic pressure after open heart surgery especially in relation to non-blood priming or blood priming].

In order to evaluate the colloid oncotic pressure (COP) is useful index of hemodynamics and respiratory recovery after open heart surgery, cardiac index (CI), pulmonary capillary wedge pressure (PCWP), (A-a) Do2 and COP were measured in 34 patients during 48 hours after the cardiopulmonary bypass (CPB). The patients were divided into non-blood priming group: 11 patients and blood priming group (23 patients). In addition, blood priming group divided into two groups, one with dopamine (more than 15 micrograms/kg/min), epinephrine or intraaortic balloon pumping (severe blood subgroup, n = 6) and the other without these treatments after open heart surgery (slight blood subgroup n = 17). The COP levels in the non-blood priming group were significantly higher than those in the blood priming group from aortic cross-clamp to 10 minutes after aortic declamping (p < 0.01). From 1 to 48 hours after CPB, COP in the non-blood priming group and slight blood subgroups was significantly higher than severe blood subgroups (p < 0.05). CI and COP-PCWP levels were significantly higher in the non-blood priming group and slight blood subgroups than those in the severe blood group (p < 0.05). It is concluded that COP is useful index of hemodynamics and respiratory recovery after open heart surgery and our priming system without blood is effective in order to eliminate the blood transfusion.

Aged↗
PubMed1994

[Development of a perceived social support scale: for a Japanese population].

Social support is increasingly attracting interest in as a factor in epidemiological research of disease risks. However, at present, few methods for measuring social support that can be credited as having reliability and validity exist in Japan. Therefore a perceived social support scale was developed in relation to a population study of a town in Fukuoka prefecture. A method for measuring functional support from several external sources was designed consisting of a self-administered test provided with only two available response options--yes & no. Pretests were conducted twice in order to evaluate content validity and adjust the number of determinants and resulted in spouse, family members, and friends being selected to be primary sources of support. A factor analysis was applied to select 10 conditions with high internal consistency for each of the sources. Responses were scored 0 or 1, for 'no' or 'yes,' respectively. Subsequently each set of 10 variables was summed into an index ranking social support conditions for each of the three sources. The three highest ranking indicators from each of the respective sources were then integrated into a single comprehensive total social support score of the individuals. The inquiry method was applied on 277 adults, aged from 40 to 69 years, in the town. Intercorrelation between the indicators of support derived from the three sources was low and coefficients of reliability ranged from 0.892 to 0.978. The score of each set of the 10 variables were incorporated into a principal components analysis in order to determine factorial validity. All of the first factor loadings of the items measuring support from both spouse and family were greater than 0.7 and high eigenvalues were obtained. Therefore the methods applied to spouse and family were considered adequate to measure a given construct. The items measuring support from friends were divided into two factors, emotional support and tangible support.

Adult↗