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S Sato

Publications and source records attributed to S Sato.

At least 271 records · Page 15Linked to original sources
PubMed2001

Tetragonal SmBa2Cu3O7-x [x = 0.74(4)].

Crystals of the title compound, samarium barium copper oxide, were prepared by a modified top-seeded solution-growth method. The crystals thus prepared showed no superconductivity down to 4.2 K. A careful examination showed that the structure closely resembles that of tetragonal YBCO, and there is no atom mixing at the Ba or other sites, within experimental accuracy. A bond-valence-sum calculation at the Ba site also indicated the absence of Sm. Each site is fully occupied by a single atom, except for the oxygen site in the basal plane of the CuO(6) octahedron. The occupancy of this oxygen site is significantly reduced [0.13 (2)], as is commonly observed in the 123 system. The atomic displacement parameters of the atoms in the CuO(2) plane, as well as of the Sm atom, are very small, indicating that two equivalent CuO(2) planes tightly sandwich the Sm atom.

Journal Article↗
PubMed2001

Determining the temperature distribution of a model vessel wall under pulsed laser irradiation: an experimental attempt to measure fibrous cap thickness and detect temperature elevation in atherosclerotic lesions.

In order to measure the temperature of atherosclerotic plaques, we developed a method to determine the temperature distribution of vessel walls using a three-layer phantom agar model. Under pulsed-laser irradiation, the thickness of upper layer corresponding to fibrous cap overlying the middle layer corresponding to atherosclerotic lesion could be calculated. The temperature was calculated from measured temperature changes under pulsed-laser irradiation.

Aorta↗
PubMed2001

A rapid bioluminescent enzyme immunoassay (BLEIA) for the detection of Shiga toxin types 1 and 2.

In recent years, Escherichia coli O157: H7 has emerged as a global public health concern. Among the more important virulence characteristics of this strain is its ability to produce one or more Shiga toxins (Stx). Traditional culture-based methods for assay of enteric toxins in foods and clinical samples are relatively slow and results can be ambiguous. In this work, we established a toxin-detection system based on bioluminescent enzyme immunoassay (BLEIA) using a simple and inexpensive device. The system could detect both Shiga toxin types 1 and 2 individually within 150 min with a detection limit for each toxin at 5 pg/ml. In our study of previously characterized Shigatoxigenic and all non-Shigatoxigenic E. coli and other bacterial species, we found all Shigatoxigenic strains to be positive and non-Shigatoxigenic E. coli and other bacterial species to be negative. This assay was also used to detect Stxs in milk and supernatant fluids from minced chicken and beef. For clinical stool samples we noted a tendency for the system to give unexpectedly high background level. Our results suggest the feasibility of using BLEIA methodology for the simple, rapid and sensitive detection of toxins from culture supernatant, various foods and clinical samples.

Animals↗
PubMed2001

Autoantibody to heat shock protein Hsp40 in sera of lung cancer patients.

Heat shock protein Hsp40 is a stress protein with chaperone activity and has a cooperative function with Hsp70 in mammalian cells. We examined the possible expression of Hsp40 in lung tumor tissues using immunoblotting and immunohistochemistry, and established an enzyme-linked immunosorbent assay (ELISA) method to detect IgG antibody to Hsp40 in the serum using purified human Hsp40. Sera were obtained from 130 normal subjects and 50 patients with lung cancer. Lung tumor tissues and cells specifically overexpressed Hsp40, and no such expression was detected in normal lung tissues. Compared with normal sera, significantly higher levels of autoantibody to Hsp40 were present in patients with lung cancer. The present study is the first to demonstrate overexpression of Hsp40 in human tumor tissue and the associated presence of autoantibody to Hsp40 in the serum. These results suggest that overexpression of Hsp40 in tumor cells may be recognized as a self-antigen.

Adenocarcinoma↗
PubMed2001

Expression of 5alpha-reductases in human epithelial ovarian cancer: its correlation with androgen receptor status.

Androgen metabolism and possible actions are considered to play some roles in human epithelial ovarian neoplasms, but the details have not been well studied. We have examined the expression of 5alpha-reductase type 1 and type 2, which catalyze the conversion of testosterone to more active androgen, 5alpha-dehydrotestosterone, and androgen receptor (AR), using immunohistochemistry (104 cases) and reverse transcription-polymerase chain reaction (RT-PCR) (16 cases) as a first step toward understanding the metabolism and possible actions of androgens in human common epithelial ovarian carcinoma. 5alpha-Reductase type 1 was immunopositive in 75 / 104 cases (72.0%), and 5alpha-reductase type 2 in 52 / 104 cases (50.0%) (P < 0.001). There was no significant correlation between patterns of immunolocalization and clinicopathological parameters examined. Median labeling index (LI) for AR was 17.8% (range 0 - 84.4%) which was significantly higher in serous carcinoma than other histological types (P < 0.001). There was a significant positive correlation between 5alpha-reductase type 1 immunoreactivity and AR LI (P = 0.0027), but no significant correlation was detected in 5alpha-reductase type 2. Results of RT-PCR analysis were also consistent with those of immunohistochemistry. The relatively wide distribution of 5alpha-reductase type 1, and its correlation to AR status in human epithelial ovarian malignancies suggest that this isozyme plays important roles in androgen metabolism and actions in these tumors.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2001

[Identification of Vibrio vulnificus from patients with otitis media and septicemia by PCR method].

Sucrose-negative colonies were isolated on TCBS agar plate from otorrhea specimens from otitis media patient in the Adult Diseases Examination Center, Hirosaki Medical Association. The isolate was identified as Vibrio vulnificus by nested PCR method which amplify V. vulnificus-specific sequences directed against 23S rRNA genes. The PCR method was applied to identify 6 strains originally isolated from septicemia patients in Kurashiki Central Hospital and formerly identified as V. vulnificus by phenotypic characteristics. When examined by the API20E system, the above PCR confirmed-V. vulnificus isolates were correctly identified as V. vulnificus with % ID 99.8, though this gave 3 different profiles. Cytotoxin-hemolysin gene was detected in otorrhea strain as well as septicemia strains by PCR method. The above results suggest that PCR method targeted cytotoxin-hemolysin gene is suitable for rapid and accurate identification of the isolate, because the result is obtained in less than 4 h. To our knowledge this is the first report on the V. vulnificus infection in Aomori Prefecture and the isolation from otorrhea.

Bacteremia↗
PubMed2001

[A clinical study on patients detected Pasteurella multocida from sputum].

We reported ten cases, (four female and six male), whose sputum cultures positive for Pasteurella multocida from 1990 to 2000. In the past eleven years increasing numbers of cases have appeared in our hospital. The majority of the cases with P. multocida possessed some underlying pulmonary diseases (seven cases, 70%), inactive lung tuberculosis or bronchiectasis. There were compromised hosts such as high ages person, steroids dependent person and diabetes mellitus patients. P. multocida was almost susceptible to antibioticus (penicillin and cephalosporins), although some erythromycin resistant strains were identified. The cats' oral cavities in our two cases were cultured and P. multocida were isolated. In our survey the prevalence of this organism is as high as 85% in cats. Our data suggests that patients who are in the high infection risk category are easily infected to P. multocida.

Adolescent↗
PubMed2001

Hepatitis delta virus minimal substrates competent for editing by ADAR1 and ADAR2.

A host-mediated RNA-editing event allows hepatitis delta virus (HDV) to express two essential proteins, the small delta antigen (HDAg-S) and the large delta antigen (HDAg-L), from a single open reading frame. One or several members of the ADAR (adenosine deaminases that act on RNA) family are thought to convert the adenosine to an inosine (I) within the HDAg-S amber codon in antigenomic RNA. As a consequence of replication, the UIG codon is converted to a UGG (tryptophan [W]) codon in the resulting HDAg-L message. Here, we used a novel reporter system to monitor the editing of the HDV amber/W site in the absence of replication. In cultured cells, we observed that both human ADAR1 (hADAR1) and hADAR2 were capable of editing the amber/W site with comparable efficiencies. We also defined the minimal HDV substrate required for hADAR1- and hADAR2-mediated editing. Only 24 nucleotides from the amber/W site were sufficient to enable efficient editing by hADAR1. Hence, the HDV amber/W site represents the smallest ADAR substrate yet identified. In contrast, the minimal substrate competent for hADAR2-mediated editing contained 66 nucleotides.

Adenosine Deaminase↗
PubMed2001

Impact of nephron-sparing surgery on quality of life in patients with localized renal cell carcinoma.

OBJECTIVES: The aim of the study is to evaluate the impact of nephron-sparing surgery on postoperative quality of life (QOL) in patients with localized renal cell carcinoma, compared with radical nephrectomy. METHODS: From 1986 to 1996, a total of 66 patients with localized small renal cell carcinoma <4 cm in diameter and a functioning contralateral renal unit underwent radical nephrectomy (n = 51) or nephron-sparing surgery (n = 15). Of these, 50 patients evaluated various dimensions of QOL using standardized self-rating questionnaires, EORTC QLQ-C30. RESULTS: There is no significant difference in 5-year overall survival between the nephron-sparing surgery group and the radical nephrectomy group. With regard to postoperative QOL, patients who underwent nephron-sparing surgery showed a significantly higher score on physical function than patients treated with radical nephrectomy (p<0.05). Nephron-sparing surgery was additionally superior to radical nephrectomy in terms of fatigue, sleep disturbance, pain and constipation. CONCLUSION: Selected patients with localized, small, unilateral renal cell carcinoma and a normal contralateral kidney will benefit from nephron-sparing surgery.

Adult↗
PubMed2001

Characterization of Ascaris-induced biphasic skin allergic reaction model in mice: possible roles of mast cells in early-phase and CD4-positive T cells in late-phase reactions.

We established an Ascaris-induced biphasic skin allergic reaction in mice. In the early-phase reaction (EPR), mast cell degranulation was observed, and tranilast inhibited ear edema. In mast-cell-deficient mice (WBB6F(1)-W/W(V) mice), ear edema in the EPR disappeared, whereas that in the late-phase reaction (LPR) remained. Eosinophils increased, and CD4-positive T cells tended to increase in the LPR. Anti-CD4 antibody, anti-IL-4 antibody and anti-IL-5 antibody all inhibited ear edema and had a tendency to inhibit eosinophil infiltration in the LPR. These data suggest that the EPR is induced by histamine released from mast cells, whereas the LPR is induced by IL-4 and IL-5 produced from CD4-positive T cells.

Animals↗
PubMed2001

Prospective study of depressive symptoms and risk of stroke among japanese.

BACKGROUND AND PURPOSE: We sought to examine the relationship between depressive symptoms and the incidence of stroke among Japanese men and women. METHODS: A 10.3-year prospective study on the relationship between depressive symptoms and the incidence of stroke was conducted with 901 men and women aged 40 to 78 years in a rural Japanese community. Depressive symptoms were measured at baseline with the use of the Zung Self-Rating Depression Scale (SDS). The incidence of stroke was ascertained under systematic surveillance. RESULTS: During the 10-year follow-up, 69 strokes (39 ischemic strokes, 10 intracerebral hemorrhages, 10 subarachnoid hemorrhages, and 10 unclassified strokes) occurred. Age- and sex-adjusted prevalence of mild depression (SDS scores >/=40) at baseline was 25% among subjects with incident stroke and 12% among subjects without stroke (P<0.01). Persons with SDS scores in the high tertile had twice the age- and sex-adjusted relative risk of total stroke as those with scores in the low tertile. The excess risk was confined to ischemic stroke. After we adjusted for body mass index, systolic blood pressure level, serum total cholesterol level, cigarette smoking, current treatment with antihypertensive medication, and history of diabetes mellitus, these relative risks remained statistically significant for total stroke (1.9; 95% CI, 1.1 to 3.5) and ischemic stroke (2.7; 95% CI, 1.2 to 6.0). CONCLUSIONS: Depressive symptoms predict the risk of stroke, specifically ischemic stroke among Japanese.

Adult↗
PubMed2001

Temperature measurement for energy-efficient ablation by thermal radiation with a microsecond time constant from the corneal surface during ArF excimer laser ablation.

Measurement of the temperature of the corneal surface during photorefractive keratectomy (PRK) is thought to be useful for monitoring the corneal ablation process, since the photothermal process has been proposed as the major mechanism of ArF excimer laser ablation. For temperature measurement, we measured thermal radiation from the corneal surface during ArF excimer laser ablation using a mercury-cadmium-telluride detector with a 1-micros time constant. To investigate the effects of temperature on ablation depth, the ablation depth of the cornea was measured by microscopy. When corneal ablation was initiated at the fluence of 65 mJ/cm2, the corneal surface temperature rose to 60-70 degrees C. The energy required for a unit-depth ablation (degrees C/microm) was lowest at 120 micro C. Monitoring of transient temperature during PRK provides important information on energy-efficient ablation, which may enable rapid and safe corneal incisions.

Animals↗
PubMed2001

Nanosized Ni/SiO2 catalyst prepared by homogeneous precipitation in wet silica gel.

A Ni/SiO2 catalyst was prepared by homogeneous precipitation of nickel hydroxide in a sol-gel-derived wet silica gel. The preparation process consists of two successive steps: gelation of silica in the presence of nickel nitrate and urea at 50 degrees C, followed by aging at higher temperature, typically at 80 degrees C, to decompose the urea. The decomposition of urea increases the pH of the solution in the wet gel, leading to the concurrence of structural rearrangement of silica gel and deposition of nickel species. As a result, the structure of the silica changes from a ramified polymeric network into particle aggregates that entrap the nickel cations in the particles. The resulting Ni/SiO2 contains large mesopores that have high thermal stability up to 1000 degrees C and highly dispersed Ni metal particles with typical crystallite size of 4 nm even at high Ni content at 20 wt%.

Catalysis↗
PubMed2001

Pulmonary arterial aneurysm with CATCH 22 syndrome--a case report.

An adult case of CATCH 22 syndrome with a pulmonary arterial aneurysm is presented. The chest radiograph showed a large massive lesion, which should be differentiated from lung cancer, mediastinal tumor, or aortic aneurysm. CATCH 22 syndrome is a developmental malformation caused by hemizygous deletion of 22q11 chromosome, which usually presents with cardiac malformation including tetralogy of Fallot, truncus arteriosus, patent arterial duct, and ventricular septal defect. Most patients with this syndrome usually die early in life.

Adult↗
PubMed2001

Intra-ischemic hypothermia attenuates intercellular adhesion molecule-1 (ICAM-1) and migration of neutrophil.

Adhesion of neutrophil to the endothelium and subsequent transmigration has been reported to contribute to progression of focal ischemia. Hypothermia has been known to attenuate ischemic insult through various mechanisms of action. The authors evaluated the effect of hypothermia on expression of intercellular adhesion molecule-1 (ICAM-1) protein and on transmigration of neutrophil with immunohistochemical method. Transient focal ischemia model in rats was employed, and animals received 2 h of either normothermic or hypothermic ischemia. To confirm the effectiveness of hypothermia on neuroprotection, cortical infarct area was compared between the two groups. Our results demonstrated that hypothermia reduced both the number of microvessels expressing ICAM-1 and that of neutrophils migrating into ischemic tissue. Comparison of cortical infarct area showed persistent protective effect. This study indicates that reduction of ICAM-1 expression and subsequent reduction of migrating neutrophil in hypothermia can contribute to attenuation of ischemic damage.

Animals↗