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Biomedical subjects

M Hatano

Publications and source records attributed to M Hatano.

At least 199 records · Page 11Linked to original sources
PubMed1988

Inability of translation of mRNA for HVJ (Sendai virus) M protein in a rat glioma cell line at nonpermissive temperatures.

The synthesis of M protein of HVJ (Sendai virus) in rat glioma (C6) cells, as has previously been reported, is selectively reduced at a nonpermissive temperature of 39 degrees C. In this phenomenon no difference was found in the viral RNA synthesis and the stability of the viral RNAs between the permissive and nonpermissive temperatures. Oligo dT-selected RNA from the infected cells at either temperature similarly directed M protein synthesis in cell-free translation reactions even if the reaction was performed at 39 degrees C. These results suggest that the restriction of M protein synthesis in C6 cells at the nonpermissive temperature might be due to the inability of translation apparatus to interact with the mRNA coding for M protein.

Animals↗
PubMed1988

Role of calcium ion in acth-induced steroidogenesis in humans.

In order to examine the role of calcium ion in ACTH-induced steroidogenesis in humans, we carried out infusion of a pharmacological dose of ACTH (4.2 micrograms/kg) and a physiological dose of ACTH (0.0084 microgram/kg) for 120 min, and infusion of dibutyryl cyclic AMP (DBcAMP) [0.33 mg/kg/min] for 20 min, in 22 normal subjects with or without verapamil treatment (360 mg/day, orally) for 5 days. The subjects were pretreated with 1.0 mg of dexamethasone and 5.0 mg of enalapril daily for 2 days before each infusion test to inhibit endogenous ACTH and angiotensin II. Following infusion of 0.0084 microgram/kg of ACTH, plasma levels of corticosterone (P less than 0.02) and cortisol (P less than 0.01) were significantly increased; with chronic verapamil treatment plasma levels of corticosterone (P less than 0.05) and cortisol (P less than 0.02) were significantly lower than those without verapamil. On the other hand, 4.2 micrograms/kg of ACTH for 120 min significantly increased the plasma levels of several steroid hormones, although there were no differences between the infusion with and without verapamil. Infusion of DBcAMP for 20 min significantly increased plasma levels of corticosterone (P less than 0.02) and cortisol (P less than 0.01), but verapamil did not affect the steroidogenic response to the DBcAMP infusion. The present results suggest that steroidogenesis induced by a physiological dose of ACTH differs from that after a pharmacological dose of ACTH or DBcAMP, and is mediated mainly by calcium ion as an intracellular messenger in man.

Adrenal Cortex Hormones↗
PubMed1988

Inhibitors of prostaglandin synthesis inhibit growth of human cytomegalovirus and reactivation of latent virus in a productively and latently infected human cell line.

Indomethacin and tetracaine, inhibitors of prostaglandin synthesis, inhibited production of infectious human cytomegalovirus (HCMV) in a human thyroid papillary carcinoma cell line (TPC-1) by 99.9% when added to cultures at the concentration of 2 x 10(-4) M during the first 24 hr after infection. Although immediate early virus proteins were synthesized at similar molar ratios in mock- and compound-treated cultures, induction of HCMV-specific DNA polymerase (one of the early virus proteins) was inhibited by treatment with these compounds, suggesting that the early stages of the virus growth cycle are most likely to be under the control of indomethacin or tetracaine action. We have previously developed an in vitro HCMV latency model system in TPC-1 cultures. This system was used to study the effect of these compounds on reactivation of the latent virus. When TPC-1 cultures preheated for 48 hr at 40.5 degrees were infected with HCMV and incubated at 40.5 degrees, the cultures could be maintained for 30 days without detection of infectious virus. The latent HCMV was reactivated within 10 days by reducing the incubation temperature from 40.5 to 37 degrees. However, when the latently infected cultures were treated with indomethacin or tetracaine immediately after being shifted to 37 degrees, reactivation of the latent virus was not observed.

Antigens, Viral↗
PubMed1988

Effects of low magnesium diet on the vascular prostaglandin and fatty acid metabolism in rats.

Deficiency of magnesium with cardiovascular effects is thought to be related to alterations in the biosynthesis of prostaglandins (PGs) in the vasculature. Measurements were made of the PGE2, 6-keto-PGF1 alpha and thromboxane B2 (TxB2) outflow from the perfused isolated mesenteric arterial bed and the fatty acid composition of the tissue in rats maintained for 14 weeks on a low magnesium (LMg) diet. The serum Mg levels were significantly decreased and the serum Ca levels were significantly increased in the LMg group as compared to the controls. The arachidonic acid concentration in the triacylglyceride fraction was significantly increased in the LMg group. Long chain polyunsaturates such as 22:4n6 and 22:6n3 were consistently increased in the LMg rats as compared to the controls in both the phospholipid and triglyceride fractions as previously reported in other tissues. The PGE2, 6-keto-PGF1 alpha and TxB2 outflows were significantly increased in the LMg group as compared to the controls. These findings suggest that the biosynthesis of eicosanoids, mainly PGI2, is stimulated in Mg deficiency, and this may provide protection against intracellular Mg depletion and Ca accumulation, so as to counteract to the constricted and hyperreactive state of the vasculature in such a condition.

Animals↗
PubMed1988

Effect of elastase on blood pressure and urinary excretions of prostaglandins and catecholamines in the spontaneously hypertensive rat (SHR).

The effects of elastase on blood pressure (B.P.) and the urinary excretions of prostaglandins (PGs) and catecholamines in the spontaneously hypertensive rat (SHR) were investigated. Male SHRs (n = 20), castrated at 4 weeks of age, were divided into 2 groups. Elastase was then dissolved in saline (5 mg/ml) and injected subcutaneously (10 mg/kg of body weight) into the SHRs of one of the 2 groups (n = 10) at 5 to 13 weeks of age, and the same dose of saline only was injected subcutaneously into the SHRs of the other group (n = 10) as a control during the same period. B.P. was measured by the tail-cuff method every 2 weeks. Urine sampling and measurement of body weight (B.Wt.) were also performed every 2 weeks. The B.P. in the elastase-administered group (184.1 +/- 3.3 mmHg) was found to be significantly lower (p less than 0.02) than that of the control group (198.0. +/- 4.3) at 9 weeks of age. A significant difference (p less than 0.01) in B.P. between the control group (204.0 +/- 4.5) and the elastase-administered group (187.3 +/- 2.7) was also observed at 13 weeks of age. The urinary excretion of 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) in the control group (5.1 +/- 0.4 ng/day/100 g B.Wt.) at 11 weeks of age was significantly lower (p less than 0.05) than that of the elastase-administered group (10.4 +/- 1.3).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Influence of spironolactone on urinary prostaglandin E2 and kinin excretion in rats.

Spironolactone was administered to spontaneously hypertensive rats (SHRs) in order to examine the urinary excretions of prostaglandin E2 (PGE2) and kinin. Thirteen SHRs were divided into 2 groups: 0.1 ml of sesame oil was administered to one group (the spironolactone-lactone-untreated group, n = 6) and 20 mg of spironolactone in 0.1 ml of sesame oil was administered to the other group (the spironolactone-treated group, n = 7) by the subcutaneous route for 10 days in succession. Determinations were then made of the body weight, blood pressure, urine volume, and excretion levels of Na, K, kinin and PGE2 in the 24-hour urine. After the animals had been killed by decapitation, blood samples were drawn for determination of the plasma renin activity (PRA). The results obtained indicated decreased blood pressure and increased urinary Na excretion in the spironolactone-treated group. On the other hand, the PGE2 excretion level in the 24-hour urine decreased markedly immediately after administration of spironolactone (p less than 0.05) and was maintained at lower levels up to the end of the experiment. However, the 24-hour urinary kinin levels showed similar changes in both the spironolactone-treated group and the untreated group with no significant difference between them. These findings suggest that spironolactone has a suppressive effect on urinary PGE2 excretion, the activity of which is not mediated by kinin production in the kidneys but is the result of a direct action of spironolactone itself.

Animals↗
PubMed1988

Diminished sympathetic excitation of locus coeruleus noradrenergic neurons in the conscious mature spontaneously hypertensive rat.

We undertook a study to determine whether the activation of the nucleus locus coeruleus might be responsible for the sympathetic hyperactivity in the spontaneously hypertensive rat (SHR). Conscious mature SHR showed increased arterial pressure and plasma catecholamines with electrical stimulation of the locus coeruleus. However, SHR showed smaller increases in arterial pressure and plasma noradrenaline than Wistar-Kyoto rats (WKY). The spontaneous unit discharge in locus coeruleus neurons responded reciprocally to peripherally induced changes in arterial pressure and blood volume. However, the unit discharge in the SHR locus coeruleus is less responsive than that in WKY. Therefore, the locus coeruleus in mature SHR does not seem to be involved in the hyperactivity of the sympathetic nervous system. However, this may not be the case in young SHR.

Animals↗
PubMed1988

Minimal-change nephrotic syndrome associated with subcutaneous eosinophilic lymphoid granuloma (Kimura's disease).

A 29-year-old Japanese male with a 19-year history of subcutaneous eosinophilic lymphoid granuloma (Kimura's disease) was referred to the Nephrology Service of the Nihon University Hospital for evaluation of edema and massive proteinuria. The renal biopsy disclosed minimal glomerular lesions. In this paper a case of nephrotic syndrome associated with eosinophilic lymphoid granuloma is reported.

Adult↗
PubMed1988

Decreased T-colony formation by lymphocytes from patients with focal glomerular sclerosis.

The T-colony-forming capacity was examined in 13 normal subjects and 8 patients with biopsy-proven focal glomerular sclerosis (FGS). Fifteen patients with chronic mesangial proliferative glomerulonephritis (CGN) without renal insufficiency were studied as a disease control. The two main assays used were the counting of T colonies formed by the patients' lymphocytes, and the measurement of T-colony-forming activity in conditioned medium from cultures of patients' lymphocytes. The levels of T-colony-forming cells (TCFC) and T-colony-stimulating factor (TCSF) were decreased in patients with FGS compared with those in normal controls and lower in FGS patients with the nephrotic syndrome (NS) than in those without NS. In contrast, these parameters in CGN patients with or without NS did not differ from normal subjects. TCSF activity for TCFC in both normal individuals and FGS patients was removed from media conditioned by phytohemagglutinin (PHA)-stimulated peripheral blood lymphocytes (PHA-LCM) with interleukin-2 (IL-2) receptor bearing cultured T cells. These in vitro findings suggest that IL-2 is the essential factor contained in PHA-LCM. Thus, depressed TCFC in FGS patients with NS may result in part from impaired generation of TCSF by lymphocytes.

Absorption↗
PubMed1988

Effects of OKY-046, a selective thromboxane A2 synthetase inhibitor, on ventricular arrhythmias and prostaglandins during coronary artery ligation and reperfusion in anesthetized dogs.

Effects of OKY-046, a selective thromboxane synthetase inhibitor, on ischemia-induced ventricular arrhythmias were investigated in anesthetized dogs. OKY-046 (30 mg/kg, intravenously) decreased ventricular arrhythmias significantly both during 30 min of coronary artery ligation and subsequent reperfusion, which corresponded with a significant reduction of thromboxane concentration, suggesting that thromboxane released during ligation is an important factor in the development of ventricular arrhythmias. Inhibition of thromboxane synthesis with OKY-046 might be useful for the prevention of ischemia-induced ventricular arrhythmias.

Acrylates↗
PubMed1988

Effect of prolonged ACTH stimulation on adrenal renin and aldosterone.

Changes in adrenal renin, which have been regarded as mediator of aldosterone secretion in the adrenal gland, following prolonged ACTH treatment were investigated in male Wistar rats. After 2 days of daily sc injection of ACTH (Cortrosyn-Zinc, 50 micrograms/day), parallel increases in adrenal renin and aldosterone, and plasma aldosterone (PA) were induced. The plasma renin activity (PRA) was slightly but not significantly decreased. Prolonged treatment with ACTH for 8 days increased the adrenal renin, causing a marked reduction in the adrenal aldosterone concentration. The degree of decrease in the PRA was again not significant and similar to that after 2 days of ACTH treatment. Contrary to previout reports which have indicated participation of adrenal renin in the regulation of aldosterone secretion in the adrenal gland, the present results showed reciprocal changes in adrenal renin and aldosterone after prolonged treatment with ACTH. The present findings suggest a complicated relation between adrenal renin and aldosterone secretion in the adrenal gland.

Adrenal Glands↗
PubMed1988

Influence of cefotaxime on renal function during the treatment of infections.

A study was conducted of the effects of cefotaxime, a third generation cephalosporin antibiotic, on the function of the kidney, using several indices of renal function including urinary concentrations of the renal enzyme N-acetyl-beta-D-glucosaminidase (NAG). In 6 patients with respiratory infections and normal renal function (group I), the urinary concentrations of NAG before and after the administration of cefotaxime 2 to 4g daily were 5.7 +/- 0.6 U/L and 5.5 +/- 0.9 U/L, respectively (NS). Similarly, 9 patients with chronic renal failure who were not undergoing haemodialysis showed pre- and post-treatment urinary NAG concentrations of 8.7 +/- 4.0 U/L and 6.6 +/- 1.7 U/L, respectively (NS), while the corresponding values in 12 renally impaired patients undergoing haemodialysis (group III) were 8.1 +/- 3.5 U/L and 8.9 +/- 3.8 U/L, respectively (NS). With regard to other parameters of renal function (serum creatinine, BUN, beta 2M, and creatinine clearance), no statistically significant differences were found between the values obtained before and after therapy with cefotaxime. Therefore, it was concluded that the influence of cefotaxime on renal function is slight, and that this antibiotic can be safely used to treat patients with infections in the presence of renal dysfunction.

Acetylglucosaminidase↗
PubMed1988

[The immunohistochemical localization of CA 15-3 in human breasts and their tumors].

The tissue distribution of CA 15-3, a breast carcinoma associated antigenic determinant, has been investigated by an avidin-biotin immunoperoxidase technique in the human breasts and in their tumors. In cases of scirrhous carcinoma, positive stainings for CA 15-3 were observed in almost all carcinoma cells. In cases of solid-tubular carcinomas and papillotubular carcinomas, the reaction was various and there was no correlation between the distribution of CA 15-3 and the clinical stage. Apical staining was recognized in both solid-tubular and papillotubular carcinomas, in benign breast tumors, and in normal breast tissues. CA 15-3 appears to be related to the degree of differentiation of the breast tissue.

Adenocarcinoma↗