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M Takashima

Publications and source records attributed to M Takashima.

At least 19 recordsLinked to original sources
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

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↗
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↗
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↗
PubMed1992

Effects of sulpiride and oxypertine on the dopaminergic system in the rat striatum.

We have examined the effects of sulpiride, oxypertine and haloperidol on the behavioral and biochemical dopamine receptor function in the rat striatum. Although acute treatment with haloperidol or oxypertine induced catalepsy, tolerance to catalepsy developed following chronic treatment with haloperidol but not with oxypertine. Rats treated with acute or chronic sulpiride did not show signs of catalepsy. Intracerebroventricular administration of sulpiride, however, induced catalepsy and tolerance developed after chronic treatment. After chronic treatment with either of these three drugs, dopamine D2 receptors were up-regulated in the striatum. While acute administration of haloperidol, sulpiride or oxypertine increased the concentration of homovanillic acid in the striatum, the rate of increases was attenuated following chronic treatment with haloperidol or sulpiride, but not with oxypertine. While acute administration of sulpiride or oxypertine decreased dopamine, the decrease was attenuated following repeated administration of sulpiride but not of oxypertine. These results suggest that the unique pharmacological profile of oxypertine may be related to its therapeutic effect of activating apathetic patients, and that both sulpiride and oxypertine may cause tardive dyskinesia, as haloperidol does.

Animals↗
PubMed1992

Clinical significance of measurement of serum D-arabinitol levels in candiduria patients.

D-Arabinitol, a major candidal metabolite, is reported to be a useful parameter to diagnose disseminated candidiasis. Conventional determination of serum D-arabinitol levels using gas-liquid chromatography is complicated and time-consuming compared with the enzymatic fluorometric assay, newly available in kits. D-Arabinitol concentrations were determined by both enzymatic fluorometric assay kits and gas-liquid chromatography, and a significant correlation (r = 0.943, p less than 0.01) was found between the two methods in 25 sera from 15 patients with candiduria. D-Arabinitol/creatinine ratios were determined using the enzymatic fluorometric assay in 39 candiduria patients (21 febrile and 18 afebrile) and 22 patients without candiduria as the control. The ratios in the febrile patients were significantly greater than those in the afebrile and the nondocumented candidiasis groups. These results suggest that knowledge of the serum D-arabinitol concentration may help to promptly diagnose invasive candidiasis, particularly Candida pyelonephritis. In addition, enzymatic fluorometric assay kits are considered to be advantageous in that they require little time and are simple to use, as compared with gas-liquid chromatography.

Candidiasis↗
PubMed1992

1,25-Dihydroxyvitamin D3 attenuates the expression of experimental murine lupus of MRL/l mice.

The murine strain MRL/l spontaneously develops a systemic lupus erythematosus (SLE)-like syndrome. An increased number of T cells and polyclonal T helper cell activity has been described in these mice suggesting a potential role for 1,25-dihydroxyvitamin-D3 [1,25-D3], an antiproliferative hormone selecting the T-helper lymphocyte subset. One month old MRL/l mice were submitted or not to 1,25-D3 0.1 microgram for 4 weeks, then 0.15 microgram given i.p. every other day for 18 weeks while maintained on a low calcium chow. Dermatologic lesions, i.e. alopecia, necrosis of the ear and scab formation, were completely inhibited by 1,25-D3 therapy. By 20 weeks, all mice had developed proteinuria. However, the degree of proteinuria was somewhat reduced in treated mice as assessed by urine protein/creatine ratios (less than 4 vs greater than 4 in treated vs untreated mice respectively). Moreover, a trend for a reduction in serum titers for anti-ssDNA antibodies was observed at 18 weeks. The active vitamin D metabolite had no effect on the development of the generalized lymphoid hyperplasia. Hypercalcemia developed when 1,25-D3 was increased to 0.15 microgram (2.62 +/- 0.12 vs 1.97 +/- 0.07 mmol/l, treated vs untreated mice respectively). These results suggest a beneficial role of 1,25-D3 in the prevention or attenuation of some manifestations of murine SLE, a model sharing many immunologic features with human SLE.

Animals↗
PubMed1992

[ESWL treatment of urinary stones at an outpatient clinic].

A total of 107 patients (age: mean 51.6, range 17-85, sex: male 71, female 36) with urinary stones in 112 renoureteral units were subjected to extracorporeal shockwave lithotripsy (ESWL) in situ using an EDAP LT-01 at an outpatient clinic between June 1990 and July 1991. All patients were given an analgesic suppository before ESWL. One ESWL session required 20-60 minutes with a repetition rate of 1.25 Hz, 2.5 Hz or 5 Hz. The effectiveness of the treatment was evaluated in 94 cases consisting of 50 renal units (R1 2, R2 46, R3 2) and 44 ureteral units (U1 16, U2 1, U3 27) three months after the final session according to the criteria reported by Sonoda. Of the 94 cases, 80 cases (85.1%) were stone free and 12 cases (12.8%) had residual fragments of less than 4 mm in diameter. Macroscopic hematuria was seen in all cases. Fever or colicky pain occurred in 3 cases. Outpatient ESWL using the EDAP LT-01 is considered to be safe and efficient for the initial treatment of urinary stones.

Adolescent↗
PubMed1992

[A trial of low-dose aspirin therapy in high-risk pregnancy].

Intra-uterine growth retardation, intra-uterine fetal death and pre-eclampsia have common abnormalities: A reduction of uteroplacental perfusion, lack of vasodilation of spiral arteries and subsequent thrombosis. These physiological processes have been explained by an imbalance between prostacyclin and thromboxane A2 production. Many studies have suggested that treatment with low-dose aspirin and steroids is effective in preventing pregnancy loss or pre-eclampsia, but the mechanism has not been established. We evaluated the effectiveness of these therapies in patients at risk for pregnancy loss with the aspect of intracellular ionized calcium mobilization. Low-dose aspirin directs the prostacyclin/thromboxane A2 balance to the dominance of prostacyclin and steroids suppress the activities of lupus anticoagulant or antiphospholipid antibodies. The intracellular ionized calcium concentration in platelets is decreased significantly after these therapies. Concerning the pathological examination of placenta, there were deposits of fibrin in only 2 out of 8 cases and there were no abnormal findings in the other 6 cases. These data show that the aggregation of platelets is suppressed in microvascular circulations. These therapies do not cause any adverse effect on the mother or fetus. It is concluded that low-dose aspirin therapy with steroids is useful for patients with a poor obstetrical history.

6-Ketoprostaglandin F1 alpha↗
PubMed1991

[Cation metabolism and the effects of circulating factors in pregnancy induced hypertension].

In order to clarify the pathophysiological significance of changes in intracellular ionized calcium and sodium levels in pregnancy induced hypertension (PIH), the intracellular ionized calcium concentration in platelets (p-[Ca2+]i) and the intracellular ionized sodium concentration in red blood cells (r-[Na+]i) were measured simultaneously in PIH women in the third trimester. p-[Ca2+]i in the first trimester showed a slightly greater increase than in the women of normal luteal phase. In the second trimester, p-[Ca2+]i decreased significantly compared to first trimester, and the third trimester and first trimester levels were the same. In women with mild and severe PIH, the levels in both groups were significantly increased compared with that in normal pregnant women. Thus mechanisms not associated with platelet activation were considered as the cause of the increase of p-[Ca2+]i of women with PIH. r-[Na+]i in mild and severe PIH were also significantly increased compared to normal pregnancy. No correlation between p-[Ca2+]i and r-[Na+]i and diastolic blood pressure was observed in normal pregnancy, but a positive correlation was observed in PIH. When the male platelets were incubated with serum from non-pregnant or normal pregnant women, p-[Ca2+]i did not show any significant changes. On the other hand, p-[Ca2+]i was significantly increased after the incubation with serum from PIH women. Moreover, p-[Ca2+]i was significantly increased after the incubation with 17 beta-estradiol, parathyroid hormone (PTH), or endothelin-1 (ET-1). These data suggest that the increase of p-[Ca2+]i and r-[Na+]i in PIH is important in the initiation and maintenance of hypertension by influencing peripheral vascular resistance, and also various factors in the serum of PIH women may contribute to the accumulation of intracellular ionized calcium in patients with PIH.

Blood Platelets↗
PubMed1991

N-methyl-D-aspartate, quisqualate and kainate receptors are all involved in transmission of photic stimulation in the suprachiasmatic nucleus in rats.

In order to clarify the neuronal transmission mechanism of photic stimulation in the suprachiasmatic nucleus (SCN), the effects of agonists and antagonists for excitatory amino acid receptors on N-acetyltransferase (NAT) activity in the pineal gland were observed following the microinjection of drugs into both sides of the nuclei. N-Methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate, and kainate (which are selective agonists for three different subtypes, i.e. NMDA, quisqualate and kainate receptors, respectively) significantly decreased NAT activity similarly to the suppressive effect of light. Moreover, compared with a control group, all the groups pretreated with a selective competitive antagonist for NMDA receptor (D-2-amino-5-phosphonovalerate or 3-((+-)-2-carboxypiperazine-4-yl)-propyl-1-phosphonate), or a selective non-competitive antagonist for non-NMDA receptors (Joro spider toxin-3 or 1-naphthylacetyl spermine) partially blocked the suppressive effect of photic stimulation on NAT activity. These results suggest that NMDA, quisqualate and kainate receptors are all involved in mediating photic stimulation in the SCN.

Acetyltransferases↗
PubMed1991

N-methyl-D-aspartate receptor participates in neuronal transmission of photic information through the retinohypothalamic tract.

In order to assess the hypothesis that excitatory amino acids (EAA) are involved in the transmission of light information from retina to suprachiasmatic nucleus (SCN) and pineal via the retinohypothalamic tract (RHT), we have determined whether injections of EAA agonist into SCN could mimic the suppressive effects of light pulse on pineal melatonin production, and whether pretreatment with antagonists could block effects of light pulse in the intact rat. Injection of the EAA agonist N-methyl-D-aspartate (NMDA: 1.0 mM; 0.5 microliter) into the SCN suppressed plasma melatonin level and pineal N-acetyltransferase activity. The pretreatment with D-aminophosphonovalerate (D-APV: 2.5 or 10 mM; 2.0 microliters) or N-[1-(2-thienyl)-cyclohexyl]-piperidine (10 mM; 2.0 microliters) which are NMDA type receptor antagonists blocked the suppressive effect of the light pulse (3.0 Ix for 2 min), while the pretreatment with neither vehicle nor L-APV (optic isomer APV: 10 mM; 2.0 microliters) could block the effect of light. Alpha-D-glutamyl-amino-methylsulfonate (10 mM; 2.0 microliters or 25 mM; 2.0 microliters), which is a relative antagonist for non-NMDA type receptor, had no effect, either. These results suggest that EAA is involved in the transmission of light information through RHT and that in rat SCN EAA operates at the NMDA type receptor on the SCN.

2-Amino-5-phosphonovalerate↗
PubMed1991

[Candida urinary tract infection with special reference to ascending pyelonephritis].

The pathogenesis of Candida urinary tract infection (UTI) has been investigated clinically and experimentally with special reference to ascending pyelonephritis in rats. Among the Candida species, Candida albicans was most frequently isolated from clinical specimens including urine in two medical centers, one in Japan and the other in the United States. The isolates of C. albicans serotype B showed a significantly lower susceptibility to 5-fluorocytosine compared to those of serotype A (p less than 0.01). The distribution pattern of the serum antibody titers against C. albicans in 20 candiduria patients (C. albicans 19 and Candida tropicalis 1) was similar to that in 23 bacterial complicated UTI patients. All patients with candiduria had underlying diseases of the urinary tract, such as neurogenic bladder, bladder cancer or benign prostatic hyperplasia: indwelling urinary catheters were present in 15 patients and all had received antimicrobial agents before the study. Ascending Candida pyelonephritis has been investigated in female rats which were transurethrally inoculated into the bladder with C. albicans ATCC 10259 strain. The incidence of Candida pyelonephritis was approximately 80% in rats treated with cyclophosphamide and more than 70% in rats with partial ureteral obstruction. There was a significant relationship between renal and urinary Candida cell populations (p less than 0.01). Furthermore, a significant relationship was revealed between renal Candida cell populations and histological grades of pyelonephritis (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗