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Biomedical subjects

Y Muramatsu

Publications and source records attributed to Y Muramatsu.

At least 73 records · Page 4Linked to original sources
PubMed1999

CT fluoroscopy-assisted needle puncture and ethanol injection for hepatocellular carcinoma: a preliminary study.

OBJECTIVE: We assessed the usefulness of real-time CT fluoroscopy for needle guidance and evaluated the clinical usefulness of a unified CT fluoroscopy and angiography system in the treatment of hepatocellular carcinoma. SUBJECTS AND METHODS: A single-session percutaneous ethanol injection was performed with CT fluoroscopy guidance and monitoring for 15 hepatocellular carcinomas with an average size of 2.5 cm (range, 0.7-4.7 cm) in 10 consecutive patients. Of these, seven lesions were not seen on sonography. To mark the lesion for puncture, we performed CT arteriography or arterial injection of iodized oil. A puncture guide was applied to 12 lesions. RESULTS: The average depth from the skin's surface to the lesion was 9.3 cm (range, 4.5-11.5 cm), and the puncture route was transthoracic in five lesions and transabdominal in 13. The overall success rate in puncturing the lesions was 94.4% (17/18 sessions). The average number of punctures was 3.3, and it significantly decreased after introduction of a puncture guide compared with freehand puncture (p < .01). The average amount of injected ethanol was 12.7 ml (range, 4-27 ml). The ratio of injected ethanol dose to calculated ethanol dose was 0.6. Local recurrence occurred in four (26.7%) of 15 lesions after an average of 5 months. CONCLUSION: Using CT fluoroscopy for guidance of the needle and for monitoring ethanol infusion in the target lesion, we have found single-session percutaneous ethanol injection to be possible for hepatocellular carcinomas smaller than 5 cm or not revealed by sonography. The puncture guidance equipment was helpful for accurate insertion of the needle into the lesion, allowing a minimum number of punctures and minimal radiation exposure.

Aged↗
PubMed1999

Short report: prevalence of antibodies against spotted fever, murine typhus, and Q fever rickettsiae in humans living in Zambia.

The causative agents of rickettsial diseases (Rickettsia conorii, R. typhi, and Coxiella burnetii) have been reported throughout the African continent. However, there have been no reports on epidemiologic surveys of these infections in Zambia. This study was designed to clarify the prevalence of three rickettsioses in 377 humans in Zambia. The seroprevalence of antibodies against R. conorii, R. typhi, and C. burnetii was 16.7%, 5.0%, and 8.2%, respectively. The rates of antibody positivity against R. conorii and C. burnetii were higher in the eastern (23.1% and 11.8%) and western (16.8% and 7.4%) areas of Zambia than in the northern (3.0% and 3.0%) area of this country. There was little difference among the three areas in the distribution of antibodies against R. typhi. Since cattle breeding is more extensive in the western and eastern areas than in the northern area, it is thought that cattle-breeding areas are foci of R. conorii and C. burnetii infections in Zambia.

Adolescent↗
PubMed1999

WF14861, a new cathepsins B and L inhibitor produced by Colletotrichum sp. II. Biological properties.

WF14861, 3-(N-(1-(N-(4-aminobutyl)-N-(3-aminopropyl)carbamoyl)-2-(4-hydroxyphenyl )ethyl)carbamoyl)oxirane-2-carboxylic acid, was obtained from the culture mycelium of Colletotrichum sp. as a novel cathepsins B and L inhibitor. WF14861 also showed inhibitory activities against bone derived crude protease and other cysteine proteases in vitro. The compound ameliorated the tissue damage and the bone destruction models of low-calcium-diet-fed mouse and adjuvant arthritis rat model.

Animals↗
PubMed1999

Determination of thorium in organs from thorotrast patients by inductively coupled plasma mass spectroscopy and x-ray fluorescence.

Concentrations of thorium were determined by inductively coupled plasma mass spectroscopy in various organs collected from Japanese Thorotrast autopsy subjects to provide information on dosimetry for Thorotrast patients. Duplicate analyses were performed for 98 samples, and data for thorium in 27 different organs were obtained. The highest thorium level was found in spleen (mean: 16,000 microgram/g wet weight), followed by liver (2100 microgram/g wet weight) and bone marrow (600 microgram/g wet weight). The other concentrations decreased in the following order: lymph node, gallbladder, testis, lung, small intestine, adrenal gland, pancreas, dura, esophagus, muscle, thyroid, large intestine, stomach, fat, kidney, urinary bladder, main artery, prostate, diaphragm, trachea, heart, cerebellum, cerebrum and intervertebral disk. The last four organs showed markedly low concentrations of 2-7 microgram/g wet weight. Compared to the background thorium levels reported in the literature for human organs, the values for the organs from Thorotrast patients (even in the organs with the lowest concentrations) were at least several thousand times higher, suggesting the importance of also considering organs with minor deposition in dosimetry. Distributions of thorium in some selected organs were studied by microbeam X-ray fluorescence. The thorium conglomerates could be identified, and images of microdistributions of thorium in the organ slices were obtained.

Humans↗
PubMed1998

Localization of Ca(2+)-binding S100 proteins in epithelial tumours of the skin.

The Ca(2+)-binding proteins S100A1, S100A2, S100A4, S100A6 and S100B were evaluated immunohistochemically in normal skin and skin appendage tumours. Epidermal basal cells, epithelial cells of sebaceous glands, hair follicle sheet epithelia and eccrine duct reacted strongly with an antiserum against human S100A2 but were nonreactive or weakly reactive to S100A1, S100A4, S100A6 and S100B. Varying types of skin appendage tumours and most peripheral cells in tumour nests of basal cell carcinoma and squamous cell carcinoma showed positive S100A2 immunoreactivity in neoplastic cells corresponding to basal cells but were nonreactive or faintly reactive for other S100 proteins. Langerhan's cells and melanocytes were labelled by S100B. Basophilic cells of calcifying epithelioma were occasionally stained with S100A2 antiserum. Eccrine poroma did not react with any S100 antiserum. Mixed tumours of the skin containing neoplastic myoepithelial cells stained strongly for S100A2 and S100B but only faintly for S100A1, S100A4, S100A6. This is the first report on selective evaluation of different S100 proteins in normal skin. These antibodies are valuable tools for better characterization of skin appendage tumours.

Animals↗
PubMed1998

Microinvasive breast carcinoma with extensive involvement of level III axillary lymph nodes: a case report.

A 44-year-old woman presented with a right huge axillary mass. Both mammography and ultrasonography revealed a primary cancer of 2.8 cm maximum diameter in the right breast and metastases in the axillary lymph nodes, both being confirmed by aspiration cytology as ductal carcinoma. Right standard radical mastectomy with level III axillary lymph node dissection was carried out. Pathologically, the tumor was diagnosed as ductal carcinoma in situ with microinvasion (DCISM), histologic grade 3. The area of stromal invasion measured 1 mm at its widest point. Sixteen of the 17 resected axillary lymph nodes contained metastases, including six level III lymph nodes. Immunohistochemical studies of the tumor revealed overexpression of p53 protein, but not that of c-erbB-2 protein. The frequency of lymph node metastases from DCISM is reported to be very low. Therefore, the present case with extensive involvement of level III lymph nodes was unusual.

Adult↗
PubMed1998

A case of giant peritoneal loose bodies mimicking calcified leiomyoma originating from the rectum.

Two giant peritoneal loose bodies were found in the pelvis in a 79-year-old man. These bodies were demonstrated by computed tomography and magnetic resonance imaging to be well circumscribed masses and to have marked calcification in their central portion. Preoperatively, these bodies had been diagnosed as a calcified leiomyoma originating from the rectum; however, surgery revealed these lesions to be detached appendices epiploica. Histological examination showed that these peritoneal loose bodies consisted of thin layers of eosinophilic substance and had no cellular component. Small peritoneal loose bodies are occasionally found during laparotomy, but such large ones measuring 6 cm are very rare. In our case, accurate diagnosis could not be obtained preoperatively, because these loose bodies mimicked calcified leiomyoma of the rectum.

Aged↗
PubMed1998

Difficult tracheal intubation in patients with retinoblastoma caused by 13q deficiency.

Anesthetic management of retinoblastoma patients is unremarkable in most cases. Patients are most often babies and laryngoscopic procedures for intubation are usually easy. However, we recently experienced two cases with retinoblastoma with whom tracheal intubation was accomplished with difficulty. We report the two cases with a review of all 5-year records of retinoblastoma (rbl) in our institution. The cases we experienced recently were all patients with rbl with deletion of the long arm of thirteenth chromosome (13q-). In the 5-year review, the incidence of the difficult intubation was significantly higher (P < 0.05) in rbl with 13q- (4/11) than in rbl without 13q- (0/147). In our experience macroglossia was noted for the difficulty in the intubation. We assume that some patients with rbl will be cases of difficult intubation even to cannot ventilate-cannot intubate level when the results of their chromosomal analysis show a deletion on the thirteenth chromosome.

Anesthesia↗
PubMed1998

Detection of Coxiella burnetii from dust in a barn housing dairy cattle.

We attempted to detect Coxiella burnetii in dust samples collected from a barn housing dairy cattle by the polymerase chain reaction (PCR) method. Ten dust samples (five from ventilation fans and five from crossbeams) were collected from two areas in a barn on a farm near Sapporo, Hokkaido. C. burnetii was detected in 5 of the 10 dust samples. It was believed that aerial contamination by C. burnetii occurred in the barn.

Air Microbiology↗
PubMed1998

11Beta-hydroxysteroid dehydrogenase type 2 in human lung: possible regulator of mineralocorticoid action.

11Beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) catalyzes the conversion of cortisol to biologically inactive cortisone and is thought to confer specificity on mineralocorticoid receptors (MR). Cortisol is a prerequisite for surfactant synthesis and fetal lung maturation. Recently, expression of 11betaHSD2 was demonstrated in human fetal lung, but its localization and possible biological roles remain unknown. Therefore, in this study, we examined immunohistochemical localization of 11betaHSD2, MR, and glucocorticoid receptor (GR) in nonpathological human lungs from fetus to adult (8 weeks gestation to 55 yr of age; n = 40) retrieved from pathology files. Both 11betaHSD2 and MR immunoreactivities were detected in airway epithelia, from bronchiole to trachea and in fetal and neonatal ciliated collecting duct cells of tracheal and bronchial glands, but were undetectable in alveoli. On the other hand, GR was detected in all cell types. These results indicate that 11betaHSD2 colocalizes with MR in human airway epithelia and suggest that 11betaHSD2 play an important role in pulmonary mineralocorticoid activity such as sodium and fluid transport.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed1998

A case of aldosterone-producing adenoma with severe postoperative hyperkalemia.

It is known that some patients with primary aldosteronism show postoperative hyperkalemia, which is due to inability of the adrenal gland to secrete sufficient amounts of aldosterone. However, hyperkalemia is generally neither severe nor prolonged, in which replacement therapy with mineralocorticoid is seldom necessary. We report a case of a 46-year-old woman with an aldosterone-producing adenoma associated with severe postoperative hyperkalemia. After unilateral adrenalectomy, the patient showed episodes of severe hyperkalemia for four months, which required not only cation-exchange resin, but also mineralocorticoid replacement. Plasma aldosterone concentration (PAC) was low, although PAC was increased after rapid ACTH test. Histological examination indicated the presence of adrenocortical tumor and paradoxical hyperplasia of zona glomerulosa in the adjacent adrenal. Immunohistochemistry demonstrated that the enzymes involved in aldosterone synthesis, such as cholesterol side chain cleavage (P-450scc), 3beta-hydroxysteroid dehydrogenase (3beta-HSD), and 21-hydroxylase (P-450c21), or the enzyme involved in glucocorticoid synthesis, 11beta-hydroxylase (P-450c11beta), were expressed in the tumor, but they were completely absent in zona glomerulosa of the adjacent adrenal. These findings were consistent with the patterns of primary aldosteronism. Serum potassium level was gradually decreased with concomitant increase in PAC. These results suggest that severe postoperative hyperkalemia of the present case was attributable to severe suppression of aldosterone synthesis in the adjacent and contralateral adrenal, which resulted in slow recovery of aldosterone secretion. It is plausible that aldosterone synthesis of adjacent and contralateral adrenal glands is severely impaired in some cases with primary aldosteronism, as glucocorticoid synthesis in Cushing syndrome.

Adenoma↗
PubMed1998

WA8242A1, A2 and B, novel secretory phospholipase A2 inhibitors produced by Streptomyces violaceusniger. II. Biological properties.

WA8242A1, A2 and B, novel inhibitors of secretory phospholipase A2 (PLA2), were obtained from Streptomyces violaceusniger No. 8242. WA8242B inhibited secretory group I and II PLA2s in a dose-dependent manner. The mode of inhibition of group II PLA2 by WA8242B was in competitive fashion. WA8242B inhibited group II PLA2-induced Prostaglandin I2 (PGI2) production by human umbilical vein endothelial cells. Furthermore, WA8242B was effective in mouse zymosan writhing model.

2-Aminoadipic Acid↗
PubMed1998

Decrease of nuclear protein phosphatase 1 activity and induction of mitotic arrest and apoptosis by a marine microalgal polysaccharide in human myeloid leukemia U937 cells.

An extracellular polysaccharide, which we designate GA3P, produced from a marine microalga dinoflagellate Gymnodinium sp. A3, has been previously reported to induce apoptosis in lymphoid and myeloid cell lines. We found that the GA3P accumulates cells into the mitotic phase of the cell cycle and decreases nuclear protein phosphatase 1 (PP1) activity in a dose-dependent manner in myeloid leukemia U937 cells. Dose-dependent patterns in the decrease of nuclear PP1 activity and in the accumulation of cells into mitotic phase or apoptotic status by the GA3P were concordant with each other, indicating that the decrease of nuclear PP1 activity at least mediates some of the etiological steps in development of mitotic arrest and apoptosis induced by the GA3P. In addition, the GA3P repressed the expression of protein levels of the PP1 catalytic subunit isoform PP1 gamma 1 gamma 1. We thus suggest that the decrease of nuclear PP1 activity is due to down-regulation of the protein levels of the PP1 gamma 1.

Animals↗
PubMed1998

Increased polyploidy, delayed mitosis and reduced protein phosphatase-1 activity associated with excess copper in the Long Evans Cinnamon rat.

Until now, it is not known whether copper hepatotoxicity impairs mitosis. Enlarged hepatocytes with huge nuclei considered as polyploids are frequently observed in the Long Evans Cinnamon (LEC) rat which exhibits an abnormal accumulation of hepatic copper due to a defect in the gene homologous to human Wilson's disease gene responsible for intracellular copper delivery. This defect may lead to a abnormal mitotic progression in increased polyploidization and is associated with excessive hepatic copper. This study was designed to examine whether excess copper impairs mitotic progression and results in increased polyploidization using a model of LEC rat liver. Polyploidy was analyzed by flow cytometry. The rate of mitotic progression was investigated using the fraction of mitotic hepatocytes or a mitosis-specific phosphoprotein retained in regeneration. Nuclear protein phosphatase-1 (PP-1) activity essential to mitotic progression was measured. The effect of excess copper on incidence of polyploidy, the rate of mitotic progression and nuclear PP-1 activity was investigated using age- or copper overload-dependent changes in them in LEC rat, or genetic profile-dependent changes of them in backcrosses. LEC rat liver showed an increase of polyploidy, a delay of mitotic progression, and a reduction of nuclear PP-1 activity. These abnormal features concurred with increase of copper concentration accompanied by changes of age in LEC rats from 2 to 4 months of age, induced by dietary copper overload in LEC rat, or caused by single genetic defect in backcrosses. Excess copper impairs mitotic progression, resulting in increased polyploidization. Nuclear PP-1 activity is likely to be at least one of targets of copper hepatotoxicity leading to impairment of mitotic progression.

Age Factors↗
PubMed1998

Fetal copper uptake and a homolog (Atp7b) of the Wilson's disease gene in rats.

LEC rats are defective at the p-type copper transport ATPase gene (Atp7b) and exhibit excessive hepatic copper accumulation. However, copper concentration in fetal liver of LEC rats is lower than that of F344 normal rats. In this study, we made fetal backcrosses between LEC and F344 normal rats. At 19 days of gestation, hepatic copper concentrations of (LECXF344)F1XLEC and LECX(LECXF344)F1 fetuses were equivalent to those of F344 and LEC fetuses, respectively, irrespective of their Atp7b genotype. Furthermore, Atp7b expression was identified in the uterus and the maternal portion of placenta, but not in the fetal portion of placenta, in pregnant F344 rats. From these results, we speculate that the Atp7b product might contribute to a copper transport system from mother to fetus in the maternal portion, but not in the fetal portion of placenta.

Adenosine Triphosphatases↗