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H Maeda

Publications and source records attributed to H Maeda.

At least 127 records · Page 7Linked to original sources
PubMed2001

Hydrogen peroxide-induced deacetylation of acetyl resorufin as a novel indicator reaction for fluorometric detection of glucose using only glucose oxidase.

Hydrogen peroxide (H2O2)-induced deacetylation of non-fluorescent acetyl resorufin (1) to fluorescent resorufin (2) as a novel indicator reaction for fluorometric detection of glucose using only glucose oxidase (GOD) is described. When a 1:1:1 mixture of 1 (in CH3CN), glucose, and GOD (each in pH 7.4 phosphate buffer) was incubated at 25 degrees C under aerobic conditions, the resulting solution turned yellow to fluorescent pink due to 2. The formation of 2 was markedly retarded on incubation under anaerobic conditions. When a mixture of 1 and H2O2 was incubated under aerobic conditions, the formation of 2 was noted as in the case of the enzymatic reaction of 1. These results demonstrated that the observed color change is brought about through deacetylation of 1 to 2 induced by H2O2 generated in GOD-catalyzed oxidation of glucose. With regard to the fluorometric traces of the enzymatic reaction with 1 (0.2 mM), GOD (0.5 mg/ml), and glucose at 25 degrees C, fluorescence intensity exhibited a linear relationship against glucose concentration between 0.2 and 2.0 mm, with a correlation coefficient of 0.997. Neither ascorbic acid, uric acid, nor bilirubin significantly interfered with the transformation of 1 to 2 through GOD-catalyzed oxidation of glucose.

Ascorbic Acid↗
PubMed2001

Resazurin as an electron acceptor in glucose oxidase-catalyzed oxidation of glucose.

The behavior of resazurin (1) as an electron acceptor in glucose oxidase (GOD)-catalyzed oxidation of glucose under anaerobic conditions is described. When a mixture of 1, glucose, and GOD in phosphate buffer (pH 7.4, 0.1 M) was incubated at 25 degrees C, the resulting solution turned purple to fluorescent pink due to the deoxygenated product, resorufin (2). On incubation of 1 with GOD alone or with H2O2 under essentially the same conditions, no color change was seen, indicating that generation of 2 in the enzymatic reaction is brought about through reduction of 1 by the reduced form (GODred) of GOD, which was also supported by the voltammetric behavior of 1. However, it was found that the enzymatic transformation of 1 to 2 is of no practical use as an indicator reaction for glucose determination using only GOD due to a slow reaction of 1 with GODred. Based on a ping-pong type mechanism with a steady-state approximation, KM and kcat for 1 as an electron acceptor from GODred were estimated to be 15+/-1.3 microM and (5.0+/-0.5) x 10(-2) s(-1), respectively.

Electrons↗
PubMed2001

Identification of N-terminal autodigestion target site in subtilisin ALP I.

Autodigestion of subtilisin ALP I (ALP I), secreted from the alkalophilic Bacillus sp. NKS-21 and its predicted amino acid sequence having about 60% identity with other alkaline subtilisins, was examined under alkaline conditions. At the alkaline pH of 12, ALP I was rapidly degraded, and almost no breakdown products were detectable. However, by incubating ALP I at 5 degrees C for an extended time, a couple of specific peptides (26.7 kDa and 25.6 kDa) were accumulated. Each of them was purified and amino acid sequences of these fragments were found. Both peptides appeared to start at Gly-19 of the mature sequence of ALP I.

Amino Acid Sequence↗
PubMed2001

Analysis of structural components and molecular construction of soybean soluble polysaccharides by stepwise enzymatic degradation.

Soybean soluble polysaccharides (SSPS) extracted from soybean cotyledons have a pectin-like structure. The core polysaccharides after treatments with four kinds of hemicellulases and a pectinase contained approximately equal numbers of L-rhamnose and D-galacturonate residues, suggesting the presence of the rhamnogalacturonan (RG) I structure consisting of the diglycosyl repeating unit, -4)-alpha-D-GalpA-(1-->2)-alpha-L-Rhap-(1-. The lengths of RG chains were calculated as approximately 15, 28, and 100 diglycosyl repeats. The RG components linked to each other by intervention of galacturonan (GN) chains, constituting the backbone of SSPS. All arabinose residues, which constitute 21% of total SSPS sugars, were found to be in side chains from RG regions, and this was also true for galactose residues, which constitute 50% of total sugars. Of arabinose residues, 94% are present as alpha-1,3- or alpha-1,5-arabinans, and 89% of galactose residues were present as beta-1,4-galactans. Galactan chains are modified with arabinose, xylose, fucose, and glucose at the sites close to the RG regions.

Arabinose↗
PubMed2001

Operable non-small cell lung cancer diagnosed by transpleural techniques : do they affect relapse and prognosis?

STUDY OBJECTIVE: We assessed whether transpleural methods for diagnosing peripheral lung cancer, such as needle aspiration or tumor excision, affect relapse and prognosis, because these techniques have potential to spread malignant cells from the tumor. DESIGN: A retrospective study. SETTING: National referral hospital. PATIENTS: We reviewed 239 patients who underwent surgery between 1990 and 1998 and for whom non-small cell lung cancer (NSCLC) of < 3 cm in maximum diameter was completely resected. The duration of postoperative follow-up ranged from 12 to 105 months, with a median period of 45 months. INTERVENTIONS: We defined the transbronchial method as using a bronchoscope, and the transpleural method as using needle aspiration cytology or tumor excision. Dichotomous variables included gender, histologic type of squamous cell carcinoma or other type of carcinoma, pathologic stage, and whether the diagnostic method was the transbronchial type only (first-line method) or the transpleural type (second-line method). RESULTS: NSCLC was diagnosed in 45 patients by the transpleural technique and in 194 patients by the transbronchial technique. There were no significant statistical differences in age of patients, gender, histologic type, pathologic stage, and tumor size. There were 42 relapses, 7 in the transpleural technique group and 35 in the transbronchial technique group (p = 0.90). Of the 7 patients in the transpleural group, there were 4 distant metastasis and 3 local relapses; of the 35 patients in the transbronchial group, there were 20 distant metastasis and 15 local relapses (p = 0.99). Pleural carcinomatosis occurred in none of the 45 patients in the transpleural group and in 1 case (0.5%) in the 194 patients in the transbronchial group (p = 0.99). Patients in the transpleural group had a statistically better 5-year survival rate than patients in the transbronchial group (79.4% vs 60.3%, p = 0.04). This is also confirmed as an independent prognostic factor in a multivariate analysis. CONCLUSIONS: Transpleural methods seem to be an advisable way to diagnose operable lung cancer that is difficult to diagnose using bronchoscopy, because these methods did not affect relapse and prognosis in the patients in our study.

Adult↗
PubMed2001

Elevated level of soluble HLA class I antigens in serum and bronchoalveolar lavage fluid in patients with sarcoidosis.

OBJECTIVE: Soluble HLA class I antigens (sHLAs) in human serum have been reported to be associated with allografts and autoimmune disease and could modify immunological reactions induced by membrane type HLAs. To investigate the clinical significance of sHLAs in sarcoidosis, we assessed concentrations of sHLAs in both serum and bronchoalveolar lavage fluid (BALF) and also examined their production by peripheral blood mononuclear cells (PBMCs) and BALF cells. METHODS: Concentrations of sHLAs were determined by enzyme-linked immunosorbent assay, using a monoclonal antibody against HLA class I (W6/32) and an enzyme-labeled polyclonal antibody to human beta2-microglobulin. PBMCs and BALF cells were cultured in the presence or absence of either LPS or PHA. PATIENTS: Serum levels of sHLAs were assessed in 96 patients with sarcoidosis and in 32 healthy control subjects. sHLAs concentrations in BALF were also investigated in 17 active sarcoidosis patients and in 13 control subjects. RESULTS: sHLAs levels in both serum and BALF were higher in sarcoidosis cases than in control subjects (p<0.05, in both). In the patients, values were significantly higher in active than in inactive stages (p<0.001) and significantly correlated with angiotensin-converting enzyme (ACE) levels. Both PBMCs and BALF cells produced enhanced amounts of sHLAs in patients with active sarcoidosis compared with those in control subjects. CONCLUSION: These results demonstrated that the level of sHLAs in serum is a useful index of disease activity of sarcoidosis, partly reflecting production by PBMCs and BALF cells.

Adult↗
PubMed2001

[A clinical study of resected bronchopulmonary carcinoids].

19 surgically treated cases with bronchopulmonary carcinoid in our hospital were studied clinically, and we discussed the criteria of limited operation for typical carcinoid. 11 cases had typical carcinoid and 8 had atypical. All patients of typical type were alive with no recurrence. No lymph node metastasis was revealed in all cases of typical type. On the contrary, in cases of atypical type, 1 had n 2 disease and 1 had distant metastasis. The five survival rates of patients with typical carcinoid was 100%, and significantly better than that of patients with atypical, 27%. Therefore, patients with typical carcinoid can be cured by limited operation, but radical operation should be indicated for atypical carcinoid.

Adult↗
PubMed2001

[Management of medical practice at home].

We present here how medical practice is managed at the patients home. Medical care at home is conducted in conjunction with a variety of professionals who provide health care in the community. The use of computers allows us to easily download information, and transfer it from the clinic to community services. Fluid replacement, total parenteral nutrition, palliative treatment of pain in cancer patients, management of urethral catheters, and other skills that are carried out at home would be stated.

Home Care Services, Hospital-Based↗
PubMed2001

[A case report of pulmonary blastoma--biphasic pulmonary blastoma].

We report a biphasic pulmonary blastoma in a 77-year-old man. In a routine chest radiographic examination, in the left upper lung field, a massive shadow that had been entirely absent one year before was detected. The preoperative imaging films showed a 10 x 8 cm, well-circumscribed solid tumor in the upper lobe of the left lung. A preoperative clinical diagnosis of primary lung cancer was considered. The intraoperative findings were that the tumor had invaded the visceral pleura with adhesion to the parietal pleura. Left upper lobectomy with lymph node sampling was performed, and since invasion of the pulmonary artery wall was confirmed, complete removal of tumor was not possible. The postoperative diagnosis was biphasic pulmonary blastoma. The patient was treated with radiotherapy up to a limit of 50 Gy, covering the area around of the left hilum. At the latest follow-up, 1 year postoperatively, the patient was clinically and radiologically free of the disease.

Aged↗
PubMed2001

[Radiographic examination of skeletalized remains of an abandoned infant: a case report with special reference to odontological findings].

A homeless couple confessed that they had buried their baby, who died at the age of three months, in the graveyard two years earlier. The recovered infantile remains had been already completely skeletonized and dismembered. However, the maxilla and mandibula of the average matured infants, the age of the body was estimated to be 1 to 2.5 months old on the basis of the degree of calcification of deciduous teeth.

Age Determination by Teeth↗
PubMed2001

[The Endotoxin 100 Reference Standard of the National Institute of Health Sciences (the Japanese Pharmacopoeia Endotoxin 100 Reference Standard) (Control 0101)].

To establish the second lot (Control 0101) of the Endotoxin 100 Reference Standard of the National Institute of Health Sciences (the Japanese Pharmacopoeia Endotoxin 100 Reference Standard), a candidate standard (CS) was prepared and then evaluated. The potency of the CS was assayed against USP Endotoxin Reference Standard (Lot G-1) and defined as containing approximately 100 endotoxin units (EU) per vial by a collaborative study in which 5 laboratories participated. Based on the results, the CS was authorized to be the second lot of the Endotoxin 100 Reference Standard containing 100 EU of endotoxin per vial.

Endotoxins↗
PubMed2000

Gender differences of exploratory eye movements: a life span study.

Exploratory eye movements of normal subjects (39 male and 39 female) were recorded using an eye-mark recorder. Four parameters mean gazing time, total number of gazing points, mean scanning length, and total scanning length) were analyzed. Subjects were divided into three life spans as prepuberty (boys and girls), adult, and postpuberty. The mean gazing time of adult women was significantly longer than that of age-matched adult men, but not between men and women in prepuberty or postpuberty (postmenopausal older women and age-matched older men). The total number of gazing points of women was significantly smaller than that of men, but not significantly different between men and women in both prepuberty and postpuberty. Both the mean scanning length and total scanning length of adult women were shorter than those of age matched adult men, but no significant differences were found between men and women in both prepuberty and postpuberty. Furthermore, the mean gazing time of adult women was longer than that of men in prepuberty and postpuberty. The total scanning length of adult men was longer than that of women in both prepuberty and postpuberty. These findings suggest that gender differences of exploratory eye movements are observed only during the adult phase, which indicates that visual information processing may be regulated by gonadal hormones in humans.

Adult↗
PubMed2000

Effects of protonation on the thermodynamic properties of alkyl dimethylamine oxides.

The effects of protonation on alkyldimethyl amine oxide micelles are reviewed, mainly with regard to dodecyl and tetradecyl homologs. The topics discussed are hydrogen ion titration properties, critical micelle concentration (CMC), area per surfactant and micelle aggregation number. A hydrogen bond hypothesis is proposed to interpret the several characteristic results associated with protonation: between two cationic species as well as between the non-ionic-cationic pair. The dipole-dipole interaction of the non-ionic micelle is discussed in relation to both: (a) the unusually high CMC values of the non-ionic micelles compared with other non-ionic surfactants with the same hydrocarbon chain; and (b) the reversal of the stability of the non-ionic and the cationic micelles at high ionic strengths. Two different approaches of the salting out effect on the ionic micelles are compared, the Chan-Mukerjee approach and ours, in relation to the non-linear Corrin-Harkins relation. The obtained salting out constants of the surfactants carrying a dodecyl chain decreased as the head group becomes more polar. Infrared and 13C-NMR spectra data are examined from the point of the specific interaction claimed by the hydrogen bond model. Mixed surfactant systems including amine oxides and the solid state phase behavior of amine oxides are both briefly reviewed.

Journal Article↗
PubMed2000

Observation of inner electron ionization from radial rydberg wave packets in two-electron atoms

We have observed multiphoton ionization of the 5s core electron from a 5snd radial Rydberg wave packet of Sr atoms using a short optical pulse. When the outer nd electron is at its outer turning point the inner 5s electron is removed from the atom, and the outer electron is left in a Sr+ Rydberg state, but when the outer electron is at the inner turning point this does not occur. Analysis of the final Sr+ Rydberg states shows that the two electrons interact as the inner electron leaves, so that the outer electron is not simply projected onto the Sr+ Rydberg states.

Journal Article↗
PubMed2000

In vitro selection of hematoporphyrin binding DNA aptamers.

DNA aptamers that bind to hematoporphyrin IX (HPIX) were isolated using an in vitro selection technique. Most aptamers obtained after the 7th and 10th rounds contained guanine-rich sequences. Binding assay using fluorescence polarization technique and structural analysis by CD spectra revealed that the parallel guanine-quartet structure of the aptamer participates in the recognition of HPIX.

Base Sequence↗
PubMed2000

Rapid detection of candidate metastatic foci in the orthotopic inoculation model of androgen-sensitive prostate cancer cells introduced with green fluorescent protein.

BACKGROUND: An in vivo spontaneous metastatic model using androgen-sensitive prostate cancer cells is needed to the better understanding of prostate cancer progression. Orthotopically inoculated LNCaP cells to SCID mice manifests metastases, but it takes no less than 12 weeks to detect them by conventional methods. METHODS: The green fluorescent protein (GFP) gene was introduced into LNCaP cells by conventional lipofection technique. Biological characteristics of a subline (LNCaP-GFP) that expressed GFP at high level were compared to those of the parental cells. LNCaP-GFP cells were orthotopically inoculated to the SCID mouse, and metastases to distant organs were chronologically examined under fluorescence microscopy. RESULTS: There was no difference in growth rates and androgen-responsiveness in vitro between LNCaP-GFP and LNCaP cells. LNCaP-GFP cells inoculated to SCID mice produced prostate specific antigen. Histopathological examination at 12 weeks after inoculation of LNCaP-GFP revealed that metastases were identified as the inoculation of LNCaP cells. Colonies consisting of a few LNCaP-GFP cells, however, were detected in the lung under fluorescence microscopy as early as 4 weeks after inoculation. CONCLUSIONS: Orthotopic inoculation of LNCaP-GFP to SCID mice may provide a useful tool to investigate the molecular mechanism of progression, in particular the early stage of metastasis, of androgen-sensitive prostate cancer cells.

Androgens↗
PubMed2000

Altered regulation of cell cycle machinery involved in interleukin-1-induced G(1) and G(2) phase growth arrest of A375S2 human melanoma cells.

Interleukin-1 (IL-1) inhibits the growth of A375S2 human melanoma cells by arresting them at G(1) and G(2) phases of the cell cycle. The arrests are preceded by a rapid decrease in kinase activities of cyclin E-Cdk2 and cyclin B1-Cdc2, which are critical for G(1)-S and G(2)-M progression, respectively. IL-1 quickly enhances the protein expression of the CDK inhibitor p21(cip1). The induced p21 binds preferentially to cyclin E-Cdk2, and the increase in p21 binding parallels the decrease in cyclin E-Cdk2 activity. Thus, p21 is likely to be responsible for the inhibition of cyclin E-Cdk2 activity and G(1) arrest. Coinciding with the decrease in cyclin B1-Cdc2 activity, there is an increase in tyrosine phosphorylation of Cdc2, suggesting that an increase in the inactive Tyr-15-phosphorylated form of Cdc2 is involved in the decrease in cyclin B1-Cdc2 activity and G(2) arrest. Furthermore, we found that IL-1 causes rapid dephosphorylation of p107, but not of pRb or p130, while the total protein levels of p130 are increased. Thus, IL-1 may exert its growth-arresting effects via p107 and p130 pathways rather than through pRb.

Cell Division↗