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S Okazaki

Publications and source records attributed to S Okazaki.

At least 91 records · Page 5Linked to original sources
PubMed1990

[Three-month oral subacute toxicity study of mofezolac (N-22) in rats].

A three-month oral subacute toxicity study of mofezolac (N-22), a non-steroidal anti-inflammatory agent, was performed using dose levels of 6, 20, 60 and 200 mg/kg in rats, and recovery was also assessed one month after withdrawal. 1. Toxic signs caused by N-22 administration, observed only in the 200 mg/kg group, were as follows: soiling around the mouth and/or nose, piloerection, anemia, diarrhea, emaciation and decreased spontaneous locomotor activity. Nine males and thirteen females in the 200 mg/kg group excreted bloody diarrhea and died of general exhaustion between weeks four and thirteen of study. 2. In the 200 mg/kg group, decrease in food consumption and suppression of body weight gain were noted in males from about week four and in females from about week six after initiation of administration, and increase in water consumption was noted in males from about week seven. 3. Urinary examination revealed a decline in urinary pH in males of the 20 mg/kg and above groups and elevation of urobilinogen levels in males of the 60 and 200 mg/kg groups. 4. Hematological examination showed decreases in erythrocyte count (RBC), hematocrit value (Ht) and hemoglobin concentration (Hb) and increase in reticulocyte rate in both sexes of the 200 mg/kg group and an increase in neutrophil rate in males of the 200 mg/kg group. 5. Biochemical examination demonstrated a decrease in chloride (Cl-) in males receiving the 20 mg/kg or above doses and a decrease in calcium (Ca++) in males of the 60 and 200 mg/kg groups. Moreover, there were decreases in cholinesterase (ChE) activity, total protein (TP) and albumin (Alb) values, as well as increases in blood urea nitrogen (BUN), uric acid (UA) and potassium (K+) in both sexes of the 200 mg/kg group, along with elevations in GOT and lactate dehydrogenase (LDH) activities in females of the 200 mg/kg group. 6. The absolute and/or relative organ weights for liver, kidneys, spleen and adrenals were increased in the 200 mg/kg group. 7. On pathological examination, perforating ulceration in the jejunum and ileum, turbid ascites, adhesion and inflammatory changes in capsules of the abdominal organs, splenomegaly, mesenteric lymph node hyperplasia and inflammatory changes in the thoracic cavity were observed in dead animals of the 200 mg/kg group. Similar pathological changes were observed in a few survival cases of the 200 mg/kg group. 8. After a one month recovery period, the above-mentioned changes had mostly recovered, indicating that they were reversible.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1990

Diffuse low-density areas in white matter on CT scans after intracarotid ACNU infusion--report of three cases.

Since 1984, we have treated 11 malignant glioma patients with intracarotid infusion of ACNU [1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)- 3-nitrosourea hydrochloride] in addition to surgical removal and irradiation. We experienced three patients, who showed clinical manifestation of leukoencephalopathy and computed tomographic (CT) findings of diffuse low-density areas in the white matter on the side of ACNU infusion. Two of the three patients showed an additional CT finding of ring enhancement in the temporo-occipital region. The histological diagnosis of the first case was radiation necrosis, while that of the others was recurrent tumor with coagulation necrosis in the surrounding brain. Our experience suggests that intracarotid ACNU infusion increases the hazard of radiation necrosis, and the optimum dose and effective mode of administration should be evaluated.

Brain↗
PubMed1989

[Subarachnoid anesthesia with hyperbaric bupivacaine].

The effect, duration and complications of subarachnoid anesthesia with hyperbaric bupivacaine solution, adjusted at a gravity of 1.044 and 1.033 by adding glucose, were compared with those of isobaric 0.5% bupivacaine anesthesia. Thirty patients undergoing surgical operations on lower abdomen or lower extremities were divided into three groups and given 2.0 to 4.0 ml of bupivacaine at L3-4 according to the body height. The upper margin of analgesic zone at 15min and 60min after the subarachnoid injection of bupivacaine was higher in the hyperbaric groups, but it receded thereafter and significant differences were found at 120min compared with the isobaric group. Hypotension occurred less frequently in the hyperbaric groups. The short duration of analgesia in the hyperbaric groups may be attributable to the lower concentrations of bupivacaine, 0.40 and 0.45%, but the low frequency of hypotension might be due to the younger mean ages of these two groups. No notable complications were found in any group. Bupivacaine solution of 0.5% with a higher gravity is desired in the market.

Adult↗
PubMed1987

Dose of urokinase for intracoronary thrombolysis in patients with acute myocardial infarction.

Intracoronary thrombolysis is a logical therapeutic method and one of the challenging new treatments of acute myocardial infarction. However, a wide dose range of urokinase has been reported, and the optimal dose has not yet been established. In this study the fibrinolytic activity in patients with recanalized coronary arteries was compared with that in those with nonrecanalized arteries. The mean doses of urokinase in the recanalized and non-recanalized groups were 910,700 +/- 161,730 international units (IU) and 1,008,000 +/- 151,800 IU, respectively. The fibrinolytic activity was measured with alpha 2-plasmin inhibitor, alpha 2-macroglobulin, fibrinogen, plasminogen, and fibrin degradation products. No significant difference was observed in the fibrinolytic activity between the recanalized and nonrecanalized groups. Because the fibrinolytic activity in the two groups was thought to be activated sufficiently and to a similar degree, it appears that 1,000,000 IU of urokinase is adequate for intracoronary thrombolysis and larger doses cannot be expected to result in a higher rate of recanalization.

Cardiac Catheterization↗
PubMed1986

[Study on the toxicity of SF-1008C (II): Subacute toxicity study in rats].

The toxicity of an elemental diet (SF-1008C) for hepatic failure and recovery after administration were investigated in Sprague-Dawley rats. The rats were orally administered the drug in doses of 10, 20 and 30 g/kg/day for five weeks, after which, recovery was studied for five weeks. The results were summarized as below: In the 30 g/kg/day group, decreases in food and water consumption were observed, while the body weight gain and the rate of body weight gain were high compared to the treated control group. In addition, urinary pH and serum total protein were lower, and serum glucose and calcium levels were higher than in the treated control group, but these results were not considered to be due to the drug's toxicity. In the 20 and 10 g/kg/day groups, a slight decrease in food consumption was observed, though the rate of body weight gain was higher than in the treated control group. Slight decreases in urinary pH and serum total protein were observed, but were not considered to be due to the toxic effect of the drug. From the above results, it was concluded that the maximal non-effect dose of SF-1008C in oral administration was 30 g/kg/day, which was the maximally applicable dose in rats.

Administration, Oral↗
PubMed1985

[Study on toxicity of halopredone acetate. (I) Acute toxicity study in mice and rats].

Since halopredone acetate (THS-201), a synthetic corticosteroid, is expected to be used clinically for intra-articular injections because of its long-lasting activity in the synovial bursa, its acute toxicity was compared with that of triamsinolone acetonide (TA) and methylprednisolone acetate (MPA). The test animals were Jcl: ICR mice and Jcl: Wistar rats, and drugs were administered orally, intraperitoneally and subcutaneously. The LD50 values of THS-201 both in mice and rats were estimated more than 5000 mg/kg at each route, and these are for above larger than those of TA or MPA. Moreover, in oral and subcutaneous administration of THS-201, no severe toxic signs were observed either in mice or in rats. In intraperitoneal injection, a few of mice and rats died after showing several clinical signs and suppression of body weight gain, and their autopsy revealed atrophy of thymus, spleen and adrenal, induction of infection and hemorrhage in digestive tract. On the other hand, the mice and rats administered TA or MPA revealed the severe toxic signs such as loss of hair gloss, marked emaciation, decrease in spontaneous movement, anemia, bloated face, decrease or suppression of body weight gain, atrophy of thymus, spleen and adrenal, severe induction of infection and lesions in digestive tracts. Accordingly, it is concluded that the acute toxicity of THS-201 in mice and rats was lower than that of TA or MPA.

Administration, Oral↗
PubMed1985

[Study on toxicity of halopredone acetate. (II). Subacute toxicity study in rats].

Halopredone acetate (THS-201), a synthetic corticosteroid, is expected to be used clinically for intra-articular injection because of its long-lasting activity in the synovial bursa. Subacute toxicity study was carried out on THS-201 by using Jcl: Wistar rats. THS-201 was subcutaneously administered to the rat in doses of 0.1, 0.5, 2.5 and 12.5 mg/kg/day, with the periods for administration and recovery being 3 and 2 months, respectively. Methylprednisolone acetate (MPA) was used for the positive control in dose of 0.5 mg/kg/day. In the group of THS-201 12.5 mg/kg, the below findings were observed: thinning of lumbar hair, swelling of injection site, suppression in body weight gain and decrease of food consumption. The lesions to lymphatic system were indicated by the examinations of peripheral blood, autopsy and histopathology. Slight changes in erythrocytic and biochemical values were seen, and foreign body granuloma was observed in injected subcutis. These findings, exception for lesion of injection site, were almost recovered after the 2 month-recovery period. In the group of THS-201 2.5 mg/kg, some of the changes were noted slightly. In the groups of THS-201 0.5 and 0.1 mg/kg, any toxic changes attributable to THS-201 were not observed. On the other hand, in the group of MPA 0.5 mg/kg, similar findings noted in THS-201 12.5 mg/kg group were observed, but these changes were recovered almost completely at the end of the 2 month-recovery period. It was concluded that the non-toxic dose and the defined toxic dose of THS-201 in this study were 0.5 and 2.5 mg/kg/day, respectively.

Animals↗
PubMed1985

[Study on toxicity of halopredone acetate. (III). Chronic toxicity study in rats].

Chronic toxicity study of halopredone acetate (THS-201), a synthetic corticosteroid, was carried out using Jcl: Wistar rats. THS-201 was subcutaneously administered to the rat in doses of 0.02, 0.1, 0.5 and 2.5 mg/kg/day, with the periods for administration and recovery being 12 and 2 months, respectively. In the group of THS-201 2.5 mg/kg, the below findings were observed: thinning of lumbar hair, suppression in body weight gain, decrease of food consumption in both sexes and decrease of water consumption in male. The lesions to lymphatic system were indicated by the examinations of hemogram, organ weight and histopathology. A few changes in urinary and biochemical values were seen, and foreign body granuloma was observed in the injected subcutis. After 2 month-recovery period, above-mentioned findings almost disappeared. In the group of THS-201 0.5 mg/kg, some of the changes were noted slightly and disappeared after the recovery period. In the groups of THS-201 0.1 and 0.02 mg/kg, any toxic changes attributable to THS-201 were not observed. It was concluded that the non-toxic dose and the defined toxic dose of THS-201 in this study were 0.1 and 0.5 mg/kg/day, respectively.

Animals↗
PubMed1984

Hormonal disturbances of fluid-electrolyte metabolism under altitude exposure in man.

Early alterations in fluid, electrolytes, and their regulating hormones were investigated in men exposed to 6,000 m simulated altitude (2 h-ascent, 2 h-sojourn, 2 h-return). Hematocrit and serum protein rose with elevated serum osmolality and reduced urine flow upon arrival at 6,000 m, suggesting decreased plasma volume probably due to hypotonic fluid shift to intracellular spaces. Serum K declined reflecting respiratory alkalosis. The exposure raised plasma antidiuretic hormone (ADH), plasma renin activity (PRA), serum cortisol and aldosterone. Increases both in ADH and aldosterone showed close correlations with that in cortisol, suggesting that ADH may be elevated by hypoxic stress in addition to elevated serum osmolality and decreased plasma volume, and that increased secretion of adrenocorticotropin may be the main cause of increased aldosterone, though PRA involvement cannot be excluded. These rises in ADH and aldosterone may act to retain body water, and the latter may exaggerate alkalosis; thus, these hormonal changes may be related to acute mountain sickness.

Adult↗
PubMed1984

[Pituitary oncocytoma].

Since the first reports of pituitary oncocytoma by Kovacs and Horvath, and Landolt and Oswald increasing numbers of cases have been reported with the advent of electron microscopy. It has been posturated that more cases were not precisely diagnosed because of lack of electron microscopic study. We reported two cases of pituitary oncocytoma and discussed clinicopathological aspects. Case 1 A 66-year-old woman had a 6 year history of visual impairment. Neurological examination revealed loss of vision on the left and decreased visual acuity (0.3) with temporal hemianopsia on the right. The endocrinological study revealed moderate panhypopituitarism. Plain skull X-ray, computed tomography and cerebral angiography showed the findings of a pituitary tumor with suprasellar extension. Subfrontal removal of the tumor followed by irradiation was performed. Case 2 A 50-year-old man was well until 8 years previously, when he experienced loss of libido. Three years before entry, the left sided exophthalmos and ptosis were noted. Neurological examination showed a severe visual impairment with a bitemporal field defect, bilateral optic atrophy and disturbance of eye movements on the left. Endocrinological study revealed panhypopituitarism. Radiological studies showed a pituitary tumor with a suprasellar extension and an invasion into the left orbital cavity. Transcranial and then transsphenoidal partial removal of the tumor were done followed by irradiation. Histological examination of the tumors revealed a poorly granurated adenoma with very weak affinity to acid dyes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗