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Biomedical subjects

R Matsui

Publications and source records attributed to R Matsui.

At least 37 records · Page 2Linked to original sources
PubMed1996

Yeast src homology region 3 domain-binding proteins involved in bud formation.

The yeast protein Bem1p, which bears two src homology region 3 (SH3) domains, is involved in cell polarization. A Rho-type GTPase, Rho3p, is involved in the maintenance of cell polarity for bud formation, and the rho3 defect is suppressed by a high dose of BEM1. Mutational analysis revealed that the second SH3 domain from the NH2 terminus (SH3-2) of Bem1p is important for the functions of Bem1p in bud formation and in the suppression of the rho3 defect. Boi2p, which bound to SH3-2 Bem1p, was identified using the two-hybrid system. Boi2p has a proline-rich sequence that is critical for displaying the Boi2p-Bem1p two-hybrid interaction, an SH3 domain in its NH2-terminal half, and a pleckstrin homology domain in its COOH-terminal half. A BOI2 homologue, BOI1, was identified as a gene whose overexpression inhibited cell growth. Cells overexpressing either BOI1 or BOI2 were arrested as large, round, and unbudded cells, indicating that the Boi proteins affect cell polarization. Genetic analysis revealed that BOI1 and BOI2 are functionally redundant and important for cell growth. delta boi1 delta boi2 cells became large round cells or lysed with buds, displaying defects in bud formation and in the maintenance of cell polarity. Analysis using several truncated versions of BOI2 revealed that the COOH-terminal half, which contains the pleckstrin homology domain is essential for the function of Boi2p in cell growth, while the NH2-terminal half is not, and the NH2-terminal half might be required for modulating the function of Bem1p. Overproduction of either Rho3p or the Rho3p-related GTPase Rho4p suppressed the boi defect. These results demonstrate that Rho3p GTPases and Boi proteins function in the maintenance of cell polarity for bud formation.

Adaptor Proteins, Signal Transducing↗
PubMed1996

[Two cases of breast cancer detected by 99mTc-tetrofosmin myocardial scintigraphy].

Breast cancer ranks the second position among the cancer of women in Japan. We report two cases of breast cancer detected by 99mTc-tetrofosmin. First case was 51 years old female with breast cancer (invasive papillotubular carcinoma) and dextrocardia. She received 99mTc-tetrofosmin myocardial scintigraphy to evaluate dextrocardia and suspicious coronary artery disease. A planar image of 99mTc-tetrofosmin myocardial scintigraphy showed myocardium at the right side, gall bladder at the left lower side and abnormal uptake on the left chest wall. Transaxial images of 99mTc-tetrofosmin myocardial SPECT showed myocardium at the right side and abnormal uptake on the left chest wall. Second case was 78 years old female with breast cancer (intracystic papillary carcinoma) and arrhythmia. 99mTc-tetrofosmin myocardial scintigraphy was performed to evaluate arrhythmia and suspicious coronary artery disease. A planar image of 99mTc-tetrofosmin myocardial scintigraphy shows hot nodule at the lateral side of the myocardium. Transaxial images of 99mTc-tetrofosmin myocardial SPECT showed abnormal uptake at the left lateral side on the chest wall. Both cases appeared illed foci as abnormal uptake with 99mTc-tetrofosmin scintigraphy, although histological diagnosis was different. We conclude that 99mTc-tetrofosmin scintigraphy is helpful for evaluating breast cancer.

Aged↗
PubMed1996

[Three-phase dynamic helical CT for hepatocellular carcinoma: optimal scanning protocol].

To assess the optimal scanning protocol for three-phase dynamic helical CT, 20 patients were examined according to the following 4 methods (5 cases each) : (1) 100 ml Iopamidol (300 mgI/ml), at a rate of 2 ml/sec ; (2) 120 ml,3 ml/sec, (3) 150 ml, 3 ml/sec ; (4) biphasic method, initial 100 ml, 3.3 ml/sec ; remaining 50 ml, 1.6 ml/sec. Assessment of the time-density curve of the aorta, and the liver parenchyma, indicated that protocol (4) was superior to the others. Using protocol (4), 32 patients (62 nodules) with hepatocellular carcinoma underwent three-phase scanning, consisting of early, late, and delayed phases. Out of 61 nodules, 43 nodules were detected as high density areas in the early phase, 7 nodules as low density areas only in the late phase, and 3 nodules as low density areas only in the delayed phase. Compared with MRI, three-phase dynamic helical CT demonstrated numerous nodules, especially those less than 10 mm in diameter, and, therefore, was useful for the detection of hepatocellular carcinoma.

Aged↗
PubMed1996

[Three-dimensional CT angiography of the portal vein using multiple threshold display].

To evaluate the usefulness of three-dimensional (3D) CT angiography of the portal vein obtained by using a multiple threshold display, 3D reconstructions were performed in 15 patients. The CT scanner employed was the Toshiba Xvigor. A volume of 150 ml of lopamidol 300 mg1/ml was administered at 3.3 ml/sec intravenously. Portal venous phase helical scanning was initiated 80 seconds after the start of the injection. Helical CT data were acquired using up to 25 continuous 1.0-sec rotations during a single breath-hold with an X-ray beam width of 7 mm and a couchtop movement speed of 7 mm/sec. Axial images were reconstructed at a section interval of 3 mm. Both the shaded surface display (SSD) and multiple threshold display (MTD) were generated by using Xtension with Sparc20. MTD was performed as follows. First, voxels, with higher CT values than that of liver parenchyma, were selected. Then, selected voxels were divided into eight parts, which were each assigned gradations of white to grey. The highest part of selected voxels, with higher CT values than that of the second branch of the portal vein, were set to white and a transparency of 0%. The other seven parts were each assigned transparencies of more than 0%. MTD images were compared with SSD in 15 cases by two radiologists. MTD images were superior to SSD images in quality, because MTD diminished surrounding artifacts due to liver parenchyma and enabled small vessels to be depicted clearly. Based on the above results, it was considered that MTD was a useful method for 3D CT angiography using enhanced helical CT.

Fatty Liver↗
PubMed1996

[A case of recurrent squamous cell carcinoma of cervix successfully treated with BOMP].

Combination chemotherapy consisting of bleomycin, vincristine, mitomycin C and cisplatin (BOMP) was applied to a case (57 years old) with recurrence of squamous cell carcinoma of the cervix. The patient with FIGO stage IIIb cervical carcinoma had been treated with radiotherapy seven years ago. She was affected by malignant pericardial effusion, and was treated with direct intrapericardial administration of cisplatin (20 mg). After instillation, ultrasonography and computed tomography showed the wall thickening of colon and marked ascites. Barium enema showed the circumferential narrowing and serrations of colon, and it was diagnosed to be carcinomatous peritonitis. She was treated with BOMP consisting of BLM (5 mg, i.m., days 1 - 5), VCR (1 mg, i.v., day 5'), MMC (8 mg, i.v., day 5), and CDDP (70 mg, d.i.v., day 5). After three courses of BOMP therapy, she achieved a complete response with few toxic effects and did not require special care. She has been free of disease for six months and her performance status is 0. This encouraging result warrants the use of this combination chemotherapy regimen in other patients with recurrent squamous cell carcinoma of the cervix.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

Evaluation of Tl-201 SPECT for monitoring the treatment of pulmonary and mediastinal tumors.

Tl-201 single photon emission computed tomography (SPECT) was performed in 88 patients with pulmonary or mediastinal tumors in order to evaluate its usefulness for the detection of disease and for the assessment of the effect of treatment. We also examined mediastinal and hilar lymph node metastasis from lung cancer. Tl-201 SPECT showed abnormal accumulation on delayed images in all lung cancer patients with tumor diameters more than 12 mm. In the 14 operated lung cancer patients, mediastinal and hilar lymph node metastases with diameters of more than 15 mm were imaged, but one with a diameter of 9 mm was missed. The retention index (RI) was 27.52 +/- 31.58 in malignant tumors and -13.67 +/- 8.15 in benign tumors (p < 0.05). The RI was significantly lower after treatment than before treatment. The interval until tumor recurrence or reactivation tended to be longer in patients who showed a significant decrease in the RI after therapy. These findings suggest the usefulness of the RI as an index of therapeutic efficacy.

Adenocarcinoma↗
PubMed1995

Tc-99m sestamibi uptake by malignant lymphoma and slow washout.

Tc-99m sestamibi has been used to detect primary brain tumors, lung tumors, and breast cancers. The authors report a patient who had superior vena cava (SVC) syndrome and underwent Tc-99m sestamibi and Tl-201 SPECT to differentiate the tumor from thrombus in the mediastinum because of an abnormal mass lesion on a contrast enhanced CT scan. An abnormal area of increased Tc-99m sestamibi uptake in the supra azygos area was demonstrated on early and delayed SPECT imaging. The washout of tumor uptake was slow. The removed tumor was confirmed to be malignant lymphoma.

Aged↗
PubMed1995

Effect of indomethacin on lung development in postnatal rats: possible role of prostaglandin in alveolar formation.

We administered 1.3 mg ip of indomethacin, a prostaglandin synthetase inhibitor, per 100 g body wt to male rat pups daily on postnatal days 4-13 and examined their lungs on day 14. Indomethacin administration produced abnormal lung structure with diminished alveolar air, increased alveolar duct air, increased mean linear intercept (gas-exchanging wall distance), diminished gas-exchanging surface area and surface-to-volume ratio, increased septal wall thickness, diminished the number of alveolar crests, and increased the number of lamellar bodies in alveolar type II cells. However, this procedure did not alter quantitative lung growth (normal lung weights, volumes, and DNA and protein contents). Tissue prostaglandin content was decreased. The total amount of lung collagen or elastin was unchanged, but when collagen was analyzed into soluble and insoluble components, soluble collagen was increased. Supplementation with 1.0 g of prostaglandin E2 per 100 g body wt to animals treated with indomethacin reduced the abnormalities in pulmonary architecture. We conclude that indomethacin affects lung structure in growing rats and that it is an unusual model in that lung growth is normal, but lung development is abnormal. We also suggest that prostaglandins may play a significant role in alveolar formation in postnatal lung development in rats.

Animals↗
PubMed1995

[In vitro uptake and release of 201Tl and 99mTc-MIBI in HeLa cell].

201Tl is useful in the diagnosis of tumor malignancy determined by the grade of washout rate to the normal tissue especially in lung tumors and thyroid tumors. 99mTc-MIBI, a tracer of myocardial blood flow is also a tumor tracer. We determined whether the growth of the tumor cell is related to the uptake and release of the these tracers in cultured cells (HeLa cell). Cultured HeLa cells were incubated for 1 hr with 10 kBq of either tracer for the kinetic study of cellular uptake and additionally incubated for 90 min with cold medium for the kinetic study of cellular release. These cells cultured with various concentrations of actinomycin D (ACD) were used to examine the correlation between cellular growth and kinetics of these tracers. The uptake in the cell reached a plateau at about 60 min and the uptake at 60 min correlated with the number of the cells and was identified for specific accumulation in the cell. The uptake of 201Tl and 99mTc-MIBI at 60 min was 5.17% and 1.32% respectively of the given dose. The release for 90 min showed almost the same tendency for these tracers. The cellular release of 201Tl with the addition of ACD was increased in association with the concentration of ACD. On the other hand, the cellular release of 99mTc-MIBI showed no change by the addition of ACD. In conclusion, 201Tl showed slower washout in high growth cells than in low growth cells, and could act as an indicator of tumor malignancy by assessment of its washout by the tumor.

Culture Media↗
PubMed1995

[Evaluation of AMI-25 enhanced MR imaging and enhanced helical CT for liver tumors].

To evaluate the diagnostic capability of superparamagnetic iron oxide enhanced MRI and enhanced helical CT, 17 patients with histologically or clinically diagnosed hepatocellular carcinoma or metastatic liver tumor and a total of 208 nodules were studied. The pulse sequences used were SE 500/20 (T1WI), SE 2000/20 (PDWI) and SE 2000/70 (T2WI). Contrast medium was administrated intravenously for more than 30 minutes at a dose of 10 mumoles Fe/kg. Enhanced MR images were obtained 30-90 minutes after the injection of contrast medium. With helical CT, 133 nodules were detected. With unenhanced MRI, 62 were detected on T1WI, 60 on PDWI and 77 on T2WI. On the other hand, with enhanced MRI, 165 were detected on T1WI, 190 on PDWI and 186 on T2WI. Enhanced MRI revealed the most nodules among these images (P < 0.05), and was especially effective in detecting small nodules less than 10 mm in diameter (P < 0.05). In conclusion, it was considered that superparamagnetic iron oxide enhanced MRI was useful for the detection of hepatic nodules and that the most adequate pulse sequence was PDWI.

Aged↗
PubMed1995

[Clinical usefulness of dipyridamole loading 99mTc-tetrofosmin myocardial scintigraphy].

This study performed to establish the most suitable method in one-day protocol and to evaluate clinical usefulness of 99mTc-tetrofosmin myocardial scintigraphy after dipyridamole infusion. Image quality and liver overlapping of the myocardial SPECT were evaluated in 107 patients with old myocardial infarction (42 cases), angina pectoris (53 cases) and others (12 cases). Left ventricular wall motion and coronary artery stenosis were compared to myocardial uptake score in 55 patients who received cardiac catheterization. The suitable image quality was acquired in early SPECT images using 259 MBq of 99mTc-tetrofosmin. The overlapping between inferior wall and liver uptake was able to minimize over 45 minutes interval from injection of 99mTc-tetrofosmin to data acquisition. The segments of normal wall motion had no perfusion defect of the myocardial SPECT in all cases (100% (148/148)). The segments of abnormal wall motion had decreased myocardial uptake of the myocardial SPECT (77% (24/31)). The agreement between coronary artery stenosis and decreased myocardial uptake was 96% (24/25) in right coronary artery, 87% (26/30) in left anterior descending coronary artery and 83% (19/23) in left circumflex coronary artery. These data suggests that image quality of dipyridamole loading 99mTc-tetrofosmin myocardial scintigraphy. Myocardial perfusion in the 99mTc-tetrofosmin myocardial scintigraphy is good correlation to both left ventricular wall motion and coronary artery stenosis.

Adult↗
PubMed1995

[Comparative examinations of serum pepsinogen I, II and gastric area using computed radiography in the atrophic gastritis].

The relationship between serum PG I, PG II levels and extent of atrophic gastritis was examined. On 64 patients (male: 32, female: 32, 51.9 years old on average) with established diagnosis of either atrophic gastritis or normal. In the X-ray gastric examination, Fuji Computed Radiography (FCR) was used to obtain clear-cut images of the gastric area. Concerning the serum PG I level, patients in the group with atrophic gastritis showed lower levels than those of the people in the group with no atrophic change, but the variation was wide, and no definite tendency was seen in the relationship between the atrophic change and the serum PG I levels. Concerning the serum PG II level, as the atrophic change progresses, the serum PG II level tended to increase gradually. A significant reduction in the PG I/II ratio was seen in the group with atrophic changes (p < 0.01) in comparison with the group with no atrophic changes, and the PG I/II value tended to decrease. In conclusion, as a relationship between the atrophic change and the serum PG levels had a wide variation, we considered to be difficult by to measure the serum PG level to understand the presence and extent of the atrophic gastritis.

Disease Progression↗
PubMed1995

[Three-dimensional helical CT angiography of the abdomen].

To evaluate the quality of three-dimensional (3D) images of the abdominal vasculature acquired using enhanced helical CT, 3D reconstructions were performed for 43 examinations (38 patients). Twenty-one of 43 examinations were also reconstructed by Maximum Intensity Projection (MIP). The CT scanner employed was the Toshiba Xforce. Helical CT data were acquired using up to 20 continuous 1.5-sec rotations with an X-ray beam width of 5 mm and a couchtop movement speed of 5 to 10 mm/1.5 sec. Axial images were reconstructed at a section interval of 2 mm. Optimal protocol on enhanced helical CT was as follows: Iopamidol 300 mg I/ml was administered intravenously using a biphasic technique (3-4 ml/sec for the initial 100 ml, followed by 0.7-1.5 ml for the remaining 50 ml), and delay times of the early and late phases were 25-35 and 90 sec, respectively. Aortic branches were clearly demonstrated on early phase, while portal branches were well defined on late phase. In the visualization of abdominal vessels, 3D images were nearly equal to MIP images. However, for anteroposterior images, MIP images were superior to 3D images in quality, because 3D images had some longitudinal direction artifacts. Three-dimensional images were considered to be useful for correctly evaluating overlapping abdominal vasculatures. From the above results, 3D and MIP images of the abdominal vasculature obtained using enhanced helical CT were considered to compensate for each other.

Abdomen↗
PubMed1994

Evaluation of the ventilation-perfusion ratio in lung diseases by simultaneous anterior and posterior image acquisition.

Ventilation and perfusion images were acquired during tidal breathing using 81mKr gas and 99mTc-MAA. Anterior and posterior functional images of V/Q and Q/V were simultaneously acquired in 34 subjects with various lung diseases and 6 healthy controls. Superimposed anterior and posterior images were constructed and histograms of the frequency distribution for ventilation, perfusion, and the V/Q ratio were displayed for both lungs as well as for the left and right lungs individually. Blood gas analysis and general lung function tests were also performed on the day before scintigraphy. A correlation between marked uneven distribution of V/Q and A-aDO2 was found. When the proportion of counts at V/Q < 0.67 and/or V/Q > 1.50 in the V/Q counts histogram was compared with A-aDO2, there was a significant positive correlation for anterior images (r = 0.684, p < 0.05), posterior images (r = 0.654, p < 0.05) and superimposed images (r = 0.696, p < 0.05). Superimposed images therefore showed the highest correlation. There was no correlation between the results of lung function testing and A-aDO2. Coronal SPECT images were also obtained in 15 patients and compared with the superimposed anterior and posterior planar images. There was a good correlation (r = 0.888, p < 0.001) between both the imaging methods regarding the marked uneven distribution of V/Q. Simultaneous anterior and posterior planar image acquisition reduces the examining time, is simple, and is noninvasive. The present results also suggest that it is useful for quantitative evaluation of the ventilation-perfusion ratio.

Adolescent↗
PubMed1994

Type I collagen formation in rat type II alveolar cells immortalised by viral gene products.

BACKGROUND: Alveolar type II (T2) cells synthesise matrix proteins such as type IV collagen and fibronectin. In contrast, a fetal rat T2 cell line has been shown to synthesise type I and III collagen as well as type IV collagen. To study regulation of collagen production in T2 cells, neonatal T2 cells immortalised by adenoviral 12SE1A gene transfer were used. It was previously reported that this immortalised cell line (E1A-T2) retains epithelial features such as tight junctions and cytokeratins but also expresses mesenchymal features such as vimentin. METHODS: Collagen production was examined in E1A-T2 and primary neonatal T2 cells using polyacrylamide gel electrophoresis. Electron microscopy was used to examine collagen deposition in E1A-T2 cell culture. To define the mechanism by which alpha 1(I) type I collagen gene expression was activated in E1A-T2 cells, a deletional analysis of alpha 1(I) promoter constructs linked to the bacterial chloramphenicol acetyltransferase gene was performed. RESULTS: E1A-T2 cells produced large amounts of type I collagen with a predominance of alpha 1(I) homotrimers; alpha 2(I) peptides were detected only in the cell layer. In contrast, primary neonatal rat T2 cell cultures produced a trace amount of type I collagen. Production of alpha 1(I) peptide chains (per microgram DNA) in E1A-T2 cell cultures was 30 times higher than that observed in primary neonatal T2 cell cultures. Electron microscopy showed deposition of type I collagen fibrils in the extracellular matrix of E1A-T2 cell cultures. Transfection studies suggested at least two cis-acting elements which mediate increased alpha 1(I) gene expression in E1A-T2 cells. CONCLUSIONS: These studies indicate that the E1A-T2 cell line may be useful for studying type I collagen gene regulation in alveolar T2 cells. These findings also raise the possibility that viral activation of type I collagen genes in alveolar epithelium may be involved in certain forms of pulmonary fibrosis.

Animals↗
PubMed1994

[Assessment of myocardial contraction and relaxation with 99mTc-tetrofosmin multi-gated myocardial SPECT].

Myocardial relaxation at the diastolic phase was not evaluated by multi-gated myocardial SPECT, although myocardial contraction at the systolic phase was studied by percent wall thickening and Bull's eye methods. We make out a myocardial volume curve and report to evaluate the myocardial relaxation using multi-gated myocardial SPECT. The study population consisted of 3 normal human subjects (3 male, 32-37 years old), 10 idiopathic cardiomyopathy, 10 coronary artery disease and 1 hypertensive heart disease combined with aortic regurgitation. All cases were injected 555 MBq of 99mTc-tetrofosmin (Amersham Healthcare Corporation) intravenously at rest. A triple detector gamma-camera (GCA-9300A, Toshiba Medical, Japan) and a data processing computer (GMS-5500A, Toshiba Medical, Japan) were used in this study. A cardiac cycle (R-R interval) was divided by 16 frames (50-80 msec per 1 frame). Eight myocardial volume curves were calculated at the anterior wall, apex and inferior wall of the vertical long axis view and were calculated at the septal wall, apex and lateral wall of the horizontal long axis view, respectively. The patterns of the myocardial volume curves were classified into 5 patterns (Normal pattern (N), Delayed Contraction pattern (DC), Delayed Relaxation pattern (DR), Mixed pattern (M) and Normal pattern with Decreased amplitude (ND)). Myocardial uptake was evaluated visually of grading into severe hypertrophy (5), hypertrophy (4), normal (3), mild hypoperfusion (2), hypoperfusion (1) and perfusion defect (0). We compared patterns of the myocardial volume curves to myocardial uptake in the same segments. It was possible to detect myocardial edge of the total 16 frames with 50-60% threshold in the normal volunteer and in patients with hypertrophic cardiomyopathy and to make a myocardial volume curve. The region of the severe myocardial perfusion defect could be detected with 20% threshold in patients with old myocardial infarction. In comparison with myocardial volume curves and myocardial uptake, 74.6% in the N pattern had a normal uptake (3), 66.7% in the ND pattern had a normal uptake (3), 61.5% in the DC pattern had a hypoperfusion segment (0, 1 or fill-in to normal uptake), 44.4% in the DR pattern had a hypertrophic segment (4, 5 or fill-in to increased uptake). The pattern of myocardial volume curve indicates myocardial contractility and relaxation in each myocardial segment.

Adult↗
PubMed1994

[A comparison among 123I-IMP SPECT, EEG and MRI in patients with temporal lobe epilepsy].

N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) single photon emission computed tomography (SPECT), electroencephalography (EEG), and magnetic resonance imaging (MRI) were performed in 19 patients with temporal lobe epilepsy during interictal stage. MRI demonstrated abnormal signal in mesial temporal lobe (hippocampus) in 10 of 19 patients and 123I-IMP SPECT showed a hypoperfusion area in 15 of 19 patients. When compared with EEG and MRI data, disagreement of the affected area was observed in 3 cases. In comparison of EEG and 123I-IMP SPECT data, disagreement of the affected area was observed in 6 cases. Although there were no disagreement in comparison of MRI and 123I-IMP SPECT. We made a reprojection data parallel to the hippocampus in 123I-IMP SPECT. These data demonstrated obviously a hypoperfusion area around the hippocampus. In cases within one month from seizure attack, wide hypoperfusion area was showed on 123I-IMP SPECT in comparison of abnormal signal area on MRI. It could be considered that a reprojection data parallel to the hippocampus was useful to know extent of hypoperfusion area in temporal lobe epilepsy.

Adult↗