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M Takashima

Publications and source records attributed to M Takashima.

At least 91 records · Page 5Linked to original sources
PubMed1996

[New method for automatic tracking of the endocardial boundary in clinical use].

This study attempted to detect the left ventricular endocardial boundary in six healthy men (volunteers) using a newly developed computerized two-dimensional echocardiography method. Automatic detection of the left ventricular endocardium was achieved by; sampling of pictures, noise reduction of the pictures, filtering, decision of the early loop, detection of the left ventricular endocardial boundary, smoothing the boundary, and correction of the boundary. This process requires only 2-3 sec. Areas of the short-axis cross-sections in systolic and diastolic phases of one cardiac cycle were obtained and the percent change rate of these areas on a cardiac cycle were calculated. These were compared with the results obtained by the manual method. The boundary of the left ventricular endocardium detected by the computerized method almost coincided with that found by the manual method. Areas and the change rates obtained were correlated with those by the manual method (areas: r = 0.86, % change rate of area: r = 0.94). This new method is suitable for clinical use.

Adult↗
PubMed1995

Gas-forming liver abscess following transcatheter hepatic arterial embolization for an iatrogenic intrahepatic pseudoaneurysm: report of a case.

We herein describe a case of gas-forming pyogenic liver abscess following transcatheter hepatic arterial embolization (THAE) for an iatrogenic intrahepatic pseudoaneurysm in a 74-year-old woman. Hemobilia developed 19 days after percutaneous transhepatic cholangio-drainage was performed for the purpose of percutaneous cholangioscopic lithotripsy for the treatment of post-gastrectomy choledocholithiasis. Celiac arteriography disclosed a saccular aneurysm in the right hepatic artery. The pseudoaneurysm was successfully occluded by THAE with gelatin powder and a stainless steel coil of the Gianturco type. Ten days after successful THAE, abdominal computed tomography revealed a gas-containing cavity, which suggested the presence of a gas-forming abscess, in the posterior hepatic segment, and percutaneous transhepatic abscess drainage was performed. Thus, impaired hepatic perfusion following effective THAE and coexisting cholangitis may play an important role in the development of a gas-forming pyogenic liver abscess.

Aged↗
PubMed1995

D-arabinitol versus mannan antigen and candidal protein antigen as a serum marker for Candida pyelonephritis.

To evaluate serum markers for the diagnosis of Candida pyelonephritis, levels of D-arabinitol, candidal mannan antigen and candidal protein antigen were measured using an enzymatic fluorometric assay, an enzyme immunoassay and a latex agglutination assay, respectively. The study group comprised 36 patients with candiduria (11 disseminated candidiasis, 9 Candida pyelonephritis and 16 colonization) and 27 without candiduria. The D-arabinitol/creatinine ratio was the only marker that differentiated between Candida pyelonephritis and colonization (p < 0.01). Using the cut-off values (1.4 mumol/mg of D-arabinitol/creatinine ratio, 0.28 of mannan/creatinine ratio (x 10(4)) and 1:4 of protein antigen titer) D-arabinitol/creatinine ratio showed the highest sensitivity in Candida pyelonephritis (77.8%) as compared to mannan/creatinine ratio (55.6%) and protein antigen titer (11.1%) although there were no differences in specificity, positive predictive value or negative predictive value. These results suggest that D-arabinitol/creatinine ratio is the most useful marker of Candida pyelonephritis.

Aged↗
PubMed1995

Influence of a cigarette smoke extract on the hormonal regulation of platelet-activating factor acetylhydrolase in rats.

We evaluated the effects of estrogen, progestin, and cigarette smoke extract (CSE) on plasma platelet-activating factor (PAF) acetylhydrolase (AH; PAF-AH) activity in rats. The effects on rat tissues of an i.v. injection of PAF were studied as part of our investigation of the mechanisms involved in thrombotic episodes. Plasma PAF-AH activity in adult female rats (14 wk of age) treated with 17 alpha-ethynylestradiol (100 micrograms/kg, 5 days) was decreased by 70%. Medroxyprogesterone (50 mg/kg, 5 days) increased PAF-AH activity by 50%. CSE (0.5 cigarette/kg, 5 days) did not alter PAF-AH activity during the treatment. However, a combination of CSE and 17 alpha-ethynylestradiol decreased plasma PAF-AH activity by 90%. The decrease in PAF-AH activity was age-dependent. The effect of medroxyprogesterone on plasma PAF-AH activity was not influenced by CSE. When PAF (5-40 nmol/kg) was injected i.v. into untreated adult female rats, 9 of 16 animals died after a 20-nmol/kg dose of PAF. Macroscopic findings included hemorrhage, hyperemia, and congestion in the lungs and heart, and necrosis-like changes in the gastrointestinal tract. Microscopically, thrombi were observed in the lungs and heart. When PAF was administered to adult female rats pretreated with sex steroid hormones, the mortality of rats with low plasma PAF-AH activity caused by 17 alpha-ethynylestradiol was increased but that of rats with high PAF-AH activity caused by medroxyprogesterone was decreased. Thus, PAF and PAF-AH may play important roles in the thrombotic episodes known to occur in female smokers who use oral contraceptives.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed1995

Adenosquamous carcinoma of the gall-bladder with gastric foveolar-type epithelium.

An 80 year old Japanese man had adenosquamous carcinoma of the gall-bladder characterized by an adenocarcinoma (AC) in the gall-bladder lumen and a squamous cell carcinoma (SCC) in the invaded region of the liver. In the AC, the tumor cells consisted of atypical columnar epithelium with pseudostratification, mimicking gastric foveolar epithelium, while atypical signet-ring cells were scattered within the SCC. There was an abrupt transition between the AC and SCC areas. The tumor cells in the AC area were intensely positive for galactose oxidase-Schiff staining, and paradoxical concanavalin A staining revealed these tumor cells to have Class II mucins. Immunohistochemically, the tumor cells in foveolar-type adenocarcinoma were diffusely positive for cathepsin D. Flow cytometrical analysis of DNA content showed the AC area to be diploid and the SCC area to be aneuploid. The S-phase fraction of the SCC area (46.9%) was larger than that of the AC area (19.5%). The positive rate of immunostaining for proliferating cell nuclear antigen in the SCC area (mean 50.627%) was larger than that of the AC area (mean 3.048%, P < 0.01). These results suggest that the AC area of this tumor, histochemically and immunohistochemically, showed gastric foveolar-type characteristics, the SCC component was squamous cell metaplasia of the pre-existing AC, and that the SCC area had a greater proliferating capacity than the AC area.

Aged↗
PubMed1995

Enhanced magnetic resonance imaging in monitoring of conservative treatment of cervical pregnancy.

We report on case of cervical pregnancy successfully treated by two 5-day courses of etoposide, embryocide with the injection of KCl, the injection of methotrexate into the placenta, and cervical curettage. We evaluated the effects of these treatments by measuring urinary human chorionic gonadotropin (hCG) titers and serial hCG beta-carboxy-terminal peptide (CTP) levels. Moreover, we used ultrasonography and magnetic resonance imaging (MRI) enhanced by gadolinium-diethylenetriamine-pentaacetic acid (Gd-DTPA) to diagnose and to evaluate the blood supply to the trophoblast. The beneficial outcomes suggest that Gd-DTPA-enhanced MRI is useful in detecting the blood supply to the trophoblast, in order to avoid the massive bleeding that results from conservation treatments. This is the first report of the usefulness of Gd-DTPA-enhanced MRI for the successful conservative treatment of cervical pregnancy.

Adult↗
PubMed1994

Microbial mutagenicity and in vitro chromosome aberration induction by FK973, a new antitumor agent.

The genotoxic activity of a new antitumor agent, FK973, was compared with that of mitomycin C (MMC) in eukaryotic and prokaryotic cells. In chromosome aberration tests using Chinese hamster fibroblast Don cells, FK973 induced a dose-related increase of aberrant cells after 6 h-pulse treatments, and the minimum effective concentrations with and without S9 were 0.625 and 0.0625 micrograms/ml, respectively. The compound increased revertant colonies in Salmonella typhimurium TA102 at the dose range of 10-5000 micrograms/plate with S9. Without S9, FK973 induced a small increase at the dose range of 500-5000 micrograms/plate in two of three independent experiments, but the number of revertant colonies was less than double that of the vehicle control. The compound did not induce any revertant colonies in colonies in S. typhimurium TA100, TA98, TA1535 or TA1537 with or without S9. MMC was confirmed to increase both chromosome aberrations in Don cells and revertant colonies in TA102. The minimum clastogenic and mutagenic concentrations without S9 were 0.0156 microgram/ml and 0.005 microgram/plate, respectively. The results indicate that FK973 needs metabolic activation to induce reverse mutation in prokaryotic cells, but caused chromosome aberrations in mammalian cells without added S9.

Animals↗
PubMed1994

Mutagenicity tests of polyoxyethylene hydrogenated castor oil 60 (HCO-60).

The genotoxicity of polyoxyethylene hydrogenated castor oil 60 (HCO-60) was examined in reverse mutation test in bacteria, chromosome aberration test in vitro and micronucleus test in mice. The in vitro tests were done with and without metabolic activation using rat liver microsomal fraction. HCO-60 did induce neither reverse mutation in Salmonella typhimurium TA100, TA98, TA1535, and TA1537 and in Escherichia coli WP2uvrA, nor chromosome aberrations in Chinese hamster V79 cells. In addition, no increase in micronucleated polychromatic erythrocytes was elicited in the bone marrow of BDF1 male and female mice. It is concluded that HCO-60 was not genotoxic in these in vitro and in vivo assays.

Animals↗
PubMed1994

[Effects of estrogen and progestin on platelet-activating factor acetylhydrolase].

Platelet-activating factor (PAF) is one of the potent proinflammatory agents and is associated with a number of human diseases, including asthma, endotoxin shock and cardiovascular diseases. Additionally, plasma PAF acetylhydrolase (PAF-AH) activity to inactivate PAF is regulated by hormones. In this study, we elucidated the effects of estrogen and progestin on plasma PAF-AH and also the effects of PAF on rat tissues to investigate the mechanisms involved in the thrombotic episode. Plasma PAF-AH activity in female adult rats treated with 17 alpha-ethynylestradiol (50 micrograms/kg, 5 days) was decreased by 50%. However, medroxyprogesterone (50 mg/kg, 5 days) increased the enzyme activity by 50%. When PAF (5 to 60 nmol/kg) was injected intravenously into non-treated female adult rats, 80% of the animals died at 20 nmol/kg of PAF. Macroscopic findings showed hemorrhage, hyperemia and congestion in the lungs and heart, and necrosis-like change in the gastrointestines. Microscopically, thrombus was observed in the lungs and heart. When PAF was administered to female adult rats pretreated with sex steroid hormones, the mortality of the rats with low plasma PAF-AH activity caused by estrogen was increased, but decreased in the animals with high enzyme activity caused by progestin. These findings suggest that the imbalance between PAF and plasma PAF-AH is one of the mechanisms involved in the thrombotic episode, and estrogen and progestin are related to the event by regulating the plasma PAF-AH activity.

Animals↗
PubMed1993

Down-regulation of ubiquitin gene expression during differentiation of human leukemia cells.

Ubiquitin, which is ligated covalently to target proteins for their acquisition of a variety of functions, is encoded by multiple unique genes in human cells: two distinct poly-ubiquitin genes with tandemly repeated sequences of 3 or 9 moieties and two mono-ubiquitin genes fused with small and large ribosomal proteins. We found that all classes of ubiquitin genes as well as the two genes encoding the ribosomal proteins S17 and L31 were expressed at abnormally high levels in various hematopoietic malignant tumor cells. In contrast, in vitro terminal differentiation of various immature leukemic cell lines, such as HL-60 promyelocytic leukemia cells and K562 erythroleukemia cells into monocytic, granulocytic and erythroid cells, induced by various agents was found to cause rapid and marked down-regulation of ubiquitin expression, irrespective of the cell type, direction of differentiation or type of signal. These findings suggest that the expressions of the multiple ubiquitin genes, coordinated with those of the ribosomal protein genes, are in a dynamic state during growth and differentiation of leukemia cells.

Cell Differentiation↗
PubMed1993

The expanding realm of ballistosporous yeasts.

The recent progress in the systematics of ballistosporous yeasts is discussed. The extensive isolation studies carried out in the last decade resulted in a marked increase in the number of ballistosporous yeast species which now number nearly fifty. The increased number of species has expanded the complexity of taxonomic properties in the following ways: expansion of the range of mol% G+C of nuclear DNA to 39-68.5, thus overlapping that of all basidiomycetous yeasts; increased complexity of conidiogenesis with the finding of the genera Ballistosporomyces and Kockovaella. Based on partial sequencing of 18S ribosomal RNA (positions 1451-1618 in Saccharomyces cerevisiae), it is suggested that mode of conidiogenesis has little value for defining genera. Consequently, ballistosporous yeasts merely represent the "ballistosporous stage" of various taxa which cover the whole evolutionary spectrum of basidiomycetous yeasts. The importance of continuing isolation of ballistosporous yeasts is stressed, which together with molecular studies, will aid further progress in the systematics of basidiomycetous yeasts.

Base Composition↗
PubMed1993

Diagnostic value of determination of serum mannan concentrations in patients with candiduria.

The diagnostic value of determination of serum mannan levels was studied in 41 patients with candiduria and 20 control patients without candiduria. The patients with candiduria comprised 18 asymptomatic afebrile patients (group 1) and 23 febrile patients with suspected Candida pyelonephritis (group 2). Mannan antigenemia (> or equal to 0.5 ng/ml) was detected in 14 patients in group 2, this rate being significantly higher than the rate of four patients in group 1 (p < 0.05) and none in the control group (p < 0.01). Serum mannan levels decreased gradually and became undetectable in six patients in whom therapy with an anticandidal agent was effective. Determination of serum mannan levels may be a useful parameter in diagnosing Candida pyelonephritis and deciding on effective treatment.

Antigens, Fungal↗
PubMed1993

Periodic mother deprivation during the light period reversed the phase of serotonin N-acetyltransferase activity rhythm of the pineal gland in rat pups.

It has been reported that nursing mother rats can postnatally entrain the circadian rhythms of blinded rat pups, such as locomotor, drinking, and corticosterone rhythms. To gain more insight in the mechanism of the postnatal entrainment of such pups' circadian rhythms, we examined the serotonin N-acetyltransferase (NAT) activity rhythm in blinded rat pups subjected to periodic mother deprivation (PMD) in which mothers were periodically deprived of their pups during either half of a day. We found that only PMD during the light period shifted the phase of NAT activity rhythm in the pups. To cause a reversal of the NAT activity rhythm, it was necessary to repeat PMD for more than 6 days. PMD for 6 h each day also shifted the phase of the blinded rat pups, but it did not reverse the NAT rhythm, even when it was repeated for 10 days. In 9-h deprivation for 10 days, however, deprivation during the first 9 h of the light period reversed the phase, although the latter 9 h failed to cause reversal of the phase. On the other hand, restricted feeding of the mother took more than 11 days to reverse the phase and a foster mother in the cross-fostering experiment failed to affect the phase of pup's rhythm, when the rhythm was determined on the 11th postnatal day. These facts indicate that PMD during the light period is a potent entrainer of the pups' circadian NAT rhythms and provide a useful method of exploring the underlying mechanism of the entrainment of the pups' rhythm by the mother.

Animals↗
PubMed1993

Phosphate metabolism during muscular contraction in starved frogs (Rana catesbeiana).

1. The muscle tension and the state of high-energy phosphate metabolism during contraction of the sartorius muscle in frogs (Rana catesbeiana) starved for 1-5 months was studied by in vivo 31P-NMR spectrometry. 2. Muscle tension began to decrease after 2-month starvation compared with the control group and decreased to about one-third of the control value after a 5-month starvation. 3. Muscle contraction induced by electrical stimulation or the use of anaerobic perfusion fluid did not decrease the concentration of creatine phosphate (PCr) or beta-ATP, and only negligibly changed the PCr/Pi ratio from starvation. 4. These results suggest a decrease in creatine kinase activity in the muscle of starved frogs.

Animals↗
PubMed1993

[A case of infected renal cyst: the usefulness of magnetic resonance imaging for preoperative diagnosis].

A 22-year-old woman was admitted to our hospital with complaints of fever and left flank and back pain. Laboratory examinations showed leukocytosis and high C-reactive protein level. On the upper pole of the left kidney, two renal cysts were disclosed by ultrasonography and computerized tomography. A simple renal cyst and an infected renal cyst could be distinguished by magnetic resonance images (MRI), because the infected renal cyst was less intense than the simple renal cyst on T2 weighted MRI. Percutaneous puncture and drainage of the cyst were performed under the guidance of ultrasonography. Bacterial culture of the infected cyst fluid was positive for E. coli. Two months after treatment, computerized tomography showed no evidence of recurrence of the infected renal cyst.

Adult↗
PubMed1993

Long-term corneal endothelial changes after intraocular lens implantation. Anterior vs posterior chamber lenses.

The use of semiflexible anterior chamber intraocular lenses, widespread during the early 1980's, has been abandoned due to the many complications associated with their use. Patients who received these lenses currently represent the majority of patients with pseudophakic bullous keratopathy. We studied the morphologic characteristics of the corneal endothelium in 20 patients who had undergone extracapsular cataract extraction followed by anterior chamber or posterior chamber intraocular lens implantation. Specular microscopy and computer-assisted morphometry were performed preoperatively, 3 months postoperatively, and once a year thereafter. The follow-up period for each subject was 5 years or longer. The endothelial cell density of the central cornea in the anterior chamber lens group decreased from 304 to 196 (x 10 cells/mm2), and in the posterior chamber lens group decreased from 315 to 269 (x 10 cells/mm2). Four patients in the anterior chamber lens group developed pseudophakic bullous keratopathy 6 or 7 years after surgery. Severe endothelial cell loss and morphologic change were seen in patients who received anterior chamber lenses.

Aged↗
PubMed1992

Modulation of cerebral acetylcholine metabolism by the dorsal diencephalic conduction system in the rat.

We investigated the effects of interruption of the impulse flow in the habenulopeduncular pathways by local infusion of tetrodotoxin on the acetylcholine and choline content in selected dopamine rich regions in the forebrain and midbrain in rats. The tetrodotoxin infusion caused a marked increase in acetylcholine content in the medial frontal cortex, striatum and ventral tegmental area+interpenduncular nucleus, but not in the limbic area or the substantia nigra, whereas choline content was reduced only in both the striatum and ventral tegmental area+interpeduncular nucleus. There was an increase in 3,4-dihydroxyphenylacetic acid content in the striatum after the manipulation. These findings suggest that the dorsal diencephalic conduction system may be involved in the integration of the activity of cholinergic neurons in the forebrain and midbrain regions and striatal dopanine neurons may play a role in the modulation of cholinergic neurons.

Acetylcholine↗