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Biomedical subjects

Y Matsui

Publications and source records attributed to Y Matsui.

At least 55 records · Page 3Linked to original sources
PubMed2003

Prevention of pleural effusion following hepatectomy using argon beam coagulation.

BACKGROUND: Postoperative pleural effusion occurs frequently after hepatectomy. The value of the argon beam coagulator (ABC) for the prevention of pleural effusion after hepatectomy in patients with hepatocellular carcinoma was studied. METHODS: Sixty patients were divided randomly into two groups: an ABC group (n = 28), in which the cut surface of the hepatic ligaments and bare area of the retroperitoneum were cauterized using an ABC, and a control group (n = 32) in which the ABC was not applied. Patient characteristics, preoperative and postoperative liver function, and postoperative pleural effusion were compared between the two groups. RESULTS: There were no significant differences between the two groups with respect to histological findings, clinical stage, type of resection, operative data, and preoperative and postoperative laboratory data. One of 28 patients in the ABC group and nine of 32 patients in the control group had pleural effusion. The incidence was significantly lower in the ABC group than in the control group (P = 0.01). Pleurocentesis was needed in two of the ten patients and thoracic drainage in four patients. CONCLUSION: Application of an ABC to the cut surface of the hepatic ligaments and bare area of retroperitoneum after liver mobilization may prevent postoperative pleural effusion.

Adult↗
PubMed2003

Prediction of functional recovery after coronary bypass surgery using quantitative gated myocardial perfusion SPECT.

Previous studies have demonstrated that myocardial perfusion imaging using 99mTc-tetrofosmin at rest allows viability assessment similar to that obtained with 201Tl imaging and 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET). The simultaneous assessment of perfusion and regional function is now available by quantitative gated myocardial perfusion single-photon emission computed tomography (SPECT). This study was designed to evaluate the utility of quantitative values of wall motion and wall thickening, calculated by quantitative gated myocardial perfusion SPECT, for the prediction of functional recovery after coronary bypass grafting (CABG). Fifty-six patients with coronary artery disease scheduled for CABG were included prospectively. All patients underwent 99mTc-tetrofosmin gated SPECT imaging at rest preoperatively and 3 months after CABG. The myocardium was divided into nine segments and the average quantitative values of regional perfusion (percentage uptake) (%), wall motion (mm) and wall thickening (%) were determined automatically using quantitative gated SPECT (QGS) software. The wall motion score was defined visually using a four-point scale (0, normal; 3, akinesis), and segments with severe asynergy (score of 2 or 3) with patent grafts were assessed. Of 77 segments with severe asynergy, 56 segments showed improved wall motion and 21 segments did not improve after CABG. The area under the receiver operating characteristic curve of wall thickening for the prediction of functional recovery was significantly higher (0.92) than that of the percentage uptake (0.77, P<0.017) or wall motion (0.60, P<0.0001). When each analysis used the optimal threshold, the wall thickening analysis (>or=10%) had a sensitivity of 95% and a specificity of 81%. These values tended to be higher than those of the percentage uptake (sensitivity, 86%; specificity, 67%). The wall motion analysis (>or=1.5 mm) had a significantly lower sensitivity of 75% and specificity of 43% than the wall thickening analysis (P=0.0038 and P=0.011, respectively). The results indicate that wall thickening, calculated by QGS software, may be more useful than regional perfusion or wall motion analysis for the prediction of functional recovery after CABG. The areas of asynergy with relatively preserved wall thickening may have the potential for improved function despite severely decreased perfusion.

Aged↗
PubMed2003

Clinicopathologic evaluation after resection for ductal adenocarcinoma of the pancreas: a retrospective, single-institution experience.

INTRODUCTION: Between April 1992 and December 2000, 167 patients with pancreatic carcinoma were evaluated and treated in our department. One hundred eight patients (64.7%) with pancreatic carcinoma underwent pancreatectomy. Of these patients, 94 had histologically proven ductal adenocarcinoma. The overall postoperative mortality rate was 3.2% (3 patients), and the morbidity rate was 35.1% (33 patients). The estimated 1-, 2-, 3-, and 5-year survival rates were 43.6%, 28.7%, 21.8%, and 12.9%, respectively. There were only six long-term survivors who survived >5 years after surgery. METHODOLOGY AND AIMS: Institutional experience with 94 consecutive patients with ductal adenocarcinoma who underwent pancreatectomy was reviewed to clarify the influence of 29 prognostic factors (5 host, 17 tumor, and 7 treatment factors). Special reference was made to determine whether these significant factors have an effect on long-term survival. Univariate and multivariate models were used to analyze the effect of prognostic factors on survival. RESULTS: Univariate analysis indicated that blood loss, operative time, postoperative complications, histopathologic lymphatic and venous permeation, lymph node metastasis, conclusive stage, conclusive curability, resection margins, serosal invasion, size of tumor, retroperitoneal invasion, major arterial invasion, and mode of histologic infiltration were associated with significantly longer survival (p < 0.05). By Cox proportional hazards survival analysis, the most powerful predictors of outcome were venous permeation, lymph node metastasis, tumor diameter, and conclusive curability. The longest-term survivor had the most advanced stage (stage IV(b)) of disease and curability C. No long-term survivors had all of the good prognostic factors (according to multivariate analysis). CONCLUSIONS: The prognosis after surgical resection of pancreatic carcinoma mostly depends on tumor factors. In this study, it was difficult to identify the determinants of long-term survival in patients with resectable tumors.

Adenocarcinoma↗
PubMed2003

Tartrate resistant acid phosphatase (TRAP) positive cells in rheumatoid synovium may induce the destruction of articular cartilage.

OBJECTIVE: To examine the role of tartrate resistant acid phosphatase (TRAP) positive mononuclear and multinucleated cells in the destruction of articular cartilage in patients with rheumatoid arthritis (RA). METHODS: The presence of TRAP positive cells in the synovial tissue of patients with RA was examined by enzyme histochemistry and immunohistochemistry. Expression of mRNAs for matrix metalloproteinases (MMPs) was assessed by the reverse transcriptase-polymerase chain reaction (RT-PCR) and northern blot analysis. Production of MMPs by mononuclear and multinucleated TRAP positive cells was examined by immunocytochemistry, enzyme linked immunosorbent assay (ELISA) of conditioned medium, and immunohistochemistry of human RA synovial tissue. In addition, a cartilage degradation assay was performed by incubation of (35)S prelabelled cartilage discs with TRAP positive cells. RESULTS: TRAP positive mononuclear cells and multinucleated cells were found in proliferating synovial tissue adjacent to the bone-cartilage interface in patients with RA. Expression of MMP-2 (gelatinase A), MMP-9 (gelatinase B), MMP-12 (macrophage metalloelastase), and MMP-14 (MT1-MMP) mRNA was detected in TRAP positive mononuclear and multinucleated cells by both RT-PCR and northern blot analysis. Immunocytochemistry for these MMPs showed that MMP-2 and MMP-9 were produced by both TRAP positive mononuclear and multinucleated cells, whereas MMP-12 and MMP-14 were produced by TRAP positive multinucleated cells. MMP-2 and MMP-9 were detected in the conditioned medium of TRAP positive mononuclear cells. TRAP positive mononuclear cells also induced the release of (35)S from prelabelled cartilage discs. CONCLUSION: This study suggests that TRAP positive mononuclear and multinucleated cells located in the synovium at the cartilage-synovial interface produce MMP-2 and MMP-9, and may have an important role in articular cartilage destruction in patients with RA.

Acid Phosphatase↗
PubMed2003

[Surgical treatment to an old patient with right coronary artery aneurysm; report of a case].

The patient was 75-year-old woman. The patient was referred to our hospital for operation due to a developing right coronary artery aneurysm. The coronary artery angiography showed that the aneurysm was 3 cm in diameter which had not existed two years previously, and with a 75% distal stenosis. The operation was made during cardiac arrest. A sapheous vein graft was used to bypass to the distal artery first. Then the aneurysm was resected, and both proximal and distal arteries were ligated. The pacemaker was implanted on the third postoperative day for sick sinus syndrome, the patient got a better recovery. Surgical treatment should be recommended to coronary artery aneurysm, and sapheous vein was a good selection for bypass graft when the diameter of native artery was relatively large.

Aged↗
PubMed2002

Ferromagnetic domain structures and nanoclusters in Nd(1/2)Sr(1/2)MnO3.

Magnetic domain structures of Nd(1/2)Sr(1/2)MnO3 were investigated by means of low-temperature Lorentz electron microscopy. On cooling, magnetic domain walls started to appear at 250 K, and they were oriented straight along the [100] and [110] directions. With a further decrease in temperature, the volume of each magnetic domain increased with discontinuous domain-wall jumps. A characteristic granular image was observed at around 140 K, near the charge-ordering transition temperature. We consider that this originated from ferromagnetic nanoclusters that appeared in the antiferromagnetic matrix.

Journal Article↗
PubMed2002

Charge/orbital ordering structure of Pr(1-x)Ca(x)MnO(3)(x = 3/8) examined by low-temperature transmission electron microscopy.

The structural phase transition of Pr(1-x)Ca(x)MnO(3)(x = 3/8) was investigated by means of low-temperature transmission electron microscopy. Superlattice reflection spots with a modulation wave vector q(1) = (0,1/2,0) appeared below 230 K, indicating formation of the d(3x(2-r(2))/d(3y(2)-r(2)) type of charge/orbital ordering. Below 150 K, a new series of superlattice reflection spots with a modulation wave vector q(2) = (1/4,1/4,1/2) appeared, suggesting an additional ordering of excess 1/8 Mn(3+), necessary due to the deviation of x from 1/2, with the occupation of the d(3z(2-r(2)) type of e(g) orbital.

Journal Article↗
PubMed2002

Collagen polymorphisms of the intervertebral disc.

The mechanical function and the collagen phenotype of the disc are complex, each a hybrid of elements of ligament and cartilage. In detail, the collagen properties are unique. Collagens I and II provide the bulk of the tissue fabric interwoven in opposing radial concentration gradients. From analysis of isolated cross-linked peptides, some degree of commingling of these major fibrillar collagens occurs down to the molecular level. Collagens V, VI, IX, XI, XII and XIV all contribute to the matrix. Collagen IX is the short molecular form that lacks a non-collagenous (NC)4 domain, not the long form found in most hyaline cartilages. Protein sequence and reverse transcriptase-PCR analysis confirmed this was the result of expression from the alternative transcription start site, not proteolysis of the long form. In view of recent reports that common single nucleotide polymorphisms in COL9A2 and COL9A3 are linked to chronic sciatica associated with disc pathology, the specific interactions and role of collagen IX in disc tissue are important to define.

Animals↗
PubMed2002

Software techniques for EELS to realize about 0.3 eV energy resolution using 300 kV FEG-TEM.

In this short communication we describe some software techniques for electron energy-loss spectrum measurement. We prepared DigitalMicrograph (Gatan) scripts for multiple spectrum acquisitions, quasi-simultaneous acquisition of low-loss and core-loss spectra, energy drift correction, and other operations. Narrow zero-loss spread of 0.27 eV is demonstrated using a 300 kV field-emission transmission electron microscope (TEM) (Hitachi, HF-3000) and a post-column energy filter (Gatan, GIF2002). The core-loss spectrum is acquired with an energy resolution of 0.36 eV with high reproducibility. The present software techniques effectively achieve the intrinsic energy resolution of electron sources. Sample scripts are provided in the Appendix.

Journal Article↗
PubMed2002

Runoff characteristics of particulate pesticides in a river from paddy fields.

Runoff characteristics of particulate pesticides from paddy fields have been intensively observed in the Koise River in Japan. The 8 pesticides that are applied to paddy fields were analyzed in both particulate and dissolved forms. The concentrations and the detection frequencies of particulate pesticides were lower than those of dissolved pesticides. The particulate pesticide concentrations in the river water were evaluated based on the soil sorption coefficient, particulate organic carbon concentration, and dissolved pesticide concentrations. The particulate pesticide concentrations in the river were higher than evaluated concentrations because the paddy soil contained more pesticides than did suspended solids in the river water discharged during rain events, and because the desorption rates of pesticides were slow. In observations made during rains, the particulate pesticide concentrations increased with the increases in both the discharge rate and the concentrations of suspended solids. The particulate loading was slight compared with dissolved loading, but particulate pesticides may be influenced by enclosed areas such as a lake or estuary because under such conditions particulate matter settles vertically and the pesticide decomposition rate in sediment is slow compared with that in water.

Adsorption↗
PubMed2002

Predicting pesticide concentrations in river water with a hydrologically calibrated basin-scale runoff model.

Hydrological diffuse pollution models require calibration before they can be used to make accurate long-term predictions for a range of hydrological and meteorological conditions. As such, the applicability of the models to the dispersion of new pesticides is limited due to the lack of calibration data. In this study, the performance of a GIS-based basin-scale runoff model for predicting the concentrations of paddy-farming pesticides in river water was examined when calibrated using hydrological data alone, without optimization based on empirical pesticide concentration data. The prediction accuracy on a daily or hourly scale was somewhat unsatisfactory due to inevitable compromises concerning rice farming schedules. However, the month-averaged pesticide concentrations were satisfactorily accurate; more than 50% of predicted values were between half and twice the observed values, considering the deficiencies of the input data, particularly for pesticide usage, which may include up to 50% error.

Calibration↗
PubMed2002

[An evaluation of the potential ischemia of the forearm after harvesting of radial artery by near infrared spectroscopy].

We evaluated the potential ischemia of the forearm after harvesting of radial artery (RA) for coronary artery bypass grafting (CABG) by near infrared spectroscopy (NIRS). The subjects consist of two groups; patients group (group P) including 18 patients who received CABG with RA and control group (group C) including 9 healthy volunteers. Group P was divided into two groups; early post operative group (group E, n = 11) and mid-term post operative group (group M, n = 7). NIRS was used to measure the recovery time (RT) in the muscles of the forearm during occlusion test. There was a significant prolongation of the RT in group P than group C. There was no significant difference of the RT between group E and group M. In conclusion, harvesting of RA may cause ischemia of the forearm and it may continue for a long time.

Aged↗
PubMed2002

The effect of flow pattern on kinetic characteristic of the biomass fixed inside porous medium.

The characteristics of the biomass fixed inside porous medium (sponge cube) have been investigated to see whether it can be recognized as biofilm. The acrylic cube is used as control medium. Three types of flow pattern of bulk water are used in the test to examine is effect on substrate transportation. From the kinetic test, it is found that the biomass fixed inside the sponge cube has biofilm characteristics. For conditions where the diffusion phenomenon is dominant, two layers whose yield constant are different to each other are confirmed from stoichiometric study. When the sponge cube is in the counter flow, it was found that the whole biomass fixed inside the medium works at the same time. It is considered that a certain amount of water is flowing through the medium when the sponge cube is exposed to counter flow. When the water is totally flowing through the sponge cube during the kinetic test by using type-3 reactor, a Michaelis-Menten type equation can represent the results of the kinetic test.

Biomass↗
PubMed2002

Early closure of growth plate causes poor growth of long bones in collagen-induced arthritis rats.

Abnormalities of the epiphyseal growth plate that occur in collagen-induced arthritis (CIA) were studied. CIA was induced in 6-week-old Lewis rats by immunization with type II collagen. Radiographic examination revealed the early closure of the epiphyseal growth plate with growth retardation of the femur and tibia. Histological evaluation confirmed the early closure of the epiphyseal growth plate accompanied by decreased intensity of safranin-O staining indicating decreased amounts of proteoglycans in the extracellular matrix (ECM) of the cartilage. Immunohistochemical methods showed that the number of chondrocytes expressing matrix metalloproteinase (MMP)-3 and/or vascular endothelial growth factor (VEGF) increased in the growth plates of CIA rats. This study confirmed that disturbances of long bone growth with early closure of the epiphyseal growth plates occur in CIA. There appeared to be overexpression of MMP-3, which may be involved with proteoglycan degradation. Additionally, VEGF, which is associated with cartilage ossification and angiogenesis, might also play a role in this event. Further clarification of the mechanism of the growth disturbance in CIA may yield clinical benefits, especially in prevention of the premature closure of growth plate that is seen in juvenile rheumatoid arthritis and other diseases.

Journal Article↗
PubMed2001

Homologous phases built by boron clusters and their vibrational properties.

We have found a series of new rare earth boron-rich solids in REBC(N) (RE: Y, Ho, Er, Tm, and Lu), systems and their structures are solved from single crystal and/or powder X-ray diffraction data. Structure analysis results show that they are homologous with B(4)C and also show trigonal symmetry. As the two basic structural units, boron icosahedra and octahedra in the new phases form in layers and stack in different sequences which form different phases. With increasing number of icosahedral layers stacking between two neighboring octahedral layers, the c-axis of the unit cell is increased and the other two edges of the unit cell are only changed slightly. Three monophases of the series have been synthesized both in powders and as single crystals. The vibrational modes of the homologous phases are analyzed from the Raman spectra and compared with that of B(4)C.

Journal Article↗
PubMed2001

Novel modular domain PB1 recognizes PC motif to mediate functional protein-protein interactions.

Modular domains mediating specific protein-protein interactions play central roles in the formation of complex regulatory networks to execute various cellular activities. Here we identify a novel domain PB1 in the budding yeast protein Bem1p, which functions in polarity establishment, and mammalian p67(phox), which activates the microbicidal phagocyte NADPH oxidase. Each of these specifically recognizes an evolutionarily conserved PC motif to interact directly with Cdc24p (an essential protein for cell polarization) and p40(phox) (a component of the signaling complex for the oxidase), respectively. Swapping the PB1 domain of Bem1p with that of p67(phox), which abolishes its interaction with Cdc24p, confers on cells temperature- sensitive growth and a bilateral mating defect. These phenotypes are suppressed by a mutant Cdc24p harboring the PC motif-containing region of p40(phox), which restores the interaction with the altered Bem1p. This domain-swapping experiment demonstrates that Bem1p function requires interaction with Cdc24p, in which the PB1 domain and the PC motif participate as responsible modules.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Hexagonal Frank--Kasper phases interpreted as modulated crystals.

The structures of the hexagonal Frank--Kasper phases F and K, which have been described in terms of the aggregation of clusters, are interpreted as modulated crystal structures. They are basically composed of two close-packed layers with ordered atomic vacancies rotated by 90 degrees to each other about their normal.

Journal Article↗