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Biomedical subjects

S Satoh

Publications and source records attributed to S Satoh.

At least 685 records · Page 38Linked to original sources
PubMed1988

Vitamin K reversible hypoprothrombinemia in rats. II. Efficacy of vitamin K on latamoxef-induced coagulopathy in rats.

Feeding of a vitamin K-deficient diet caused the development of hypoprothrombinemic changes in rats such as prolongation of prothrombin time (PT) and activated partial thromboplastin time (APTT), decreases in plasma prothrombin and clotting factor VII levels, and an increase in the descarboxyprothrombin (PIVKA) level in both plasma and liver. Successive administrations of latamoxef (LMOX) to the vitamin K-deficient rats resulted in the further enhancement of these changes. After the development of hypoprothrombinemia with LMOX, a single subcutaneous injection of vitamin K1 normalized most of these abnormalities in blood coagulation parameters within 6 hr. When vitamin K was given at 200 micrograms/kg, PT, APTT and the plasma PIVKA level showed normal values for at least 8 days even when the animals were fed a vitamin K-deficient diet and treated with LMOX during the recovery period. The amount of vitamin K required to maintain most of the blood coagulation parameters in the normal range was about 3 micrograms/kg/day. The plasma level of vitamin K was higher than 0.3-0.5 ng/ml when the blood coagulation parameters were maintained in the normal range.

Animals↗
PubMed1988

Inhibitory effect of cilazaprilat on norepinephrine release induced by renal nerve stimulation in anesthetized dogs.

In pentobarbital-anesthetized dogs, the increase in the renal norepinephrine secretion rate elicited by renal nerve stimulation (1 Hz) during infusion of angiotensin I (15 ng/kg/min) was partially but significantly inhibited (by 21-37%) after dosing with cilazaprilat (0.1 mg/kg), an angiotensin converting enzyme inhibitor, accompanied by a decrease in the renal venous plasma norepinephrine concentration. These results may suggest that cilazaprilat exerts at least a part of its hypotensive effect through decreasing the facilitatory action of endogenous angiotensin II on adrenergic transmission.

Angiotensin I↗
PubMed1988

Load dependency of end-systolic pressure-volume relations in isolated, ejecting canine hearts.

If characteristic muscle properties such as myocardial viscosity and/or shortening deactivation influence left ventricular ejection in the whole heart, the slope of the left ventricular end-systolic pressure-volume relation should be a function of both the contractile state and the loading mode. Thus, the load dependence of the end-systolic pressure-volume relation was examined using isolated, perfused canine hearts ejecting saline into a hydraulic loading system. The instantaneous left ventricular volume was measured with a plethysmograph. Under constant coronary flow and heart rate, two regression lines for end-systolic pressure-volume relations in two sets of loading modes were obtained: (1) Preload (left ventricular end-diastolic pressure; 4-15 mmHg) changes under fixed afterload impedance (preload changes); (2) Afterload impedance (peripheral resistance; 1.9-9.6 x 10(3) dyn sec cm-5) changes under fixed left ventricular end-diastolic volume (afterload changes). The slope of the end-systolic pressure-volume relation with afterload changes was steeper than that with preload changes (6.3 +/- 0.7 vs 4.8 +/- 0.6 mmHg/ml, p less than 0.05). Accordingly, under constant coronary flow, the slope of the end-systolic pressure-volume relation depended on loading conditions within the physiological range of afterload impedance and preload. This finding supports our hypothesis and implies that the slope change is of limited value as a contractile index in the ejecting heart.

Animals↗
PubMed1988

Effects of androgen on 17 beta-estradiol production by cultured human granulosa cells.

In order to determine whether androgen acts solely as a substrate for aromatization or whether it also influences on the activity of aromatase enzyme, human granulosa cells were incubated in vitro with or without androgen. Although basal production of 17 beta-estradiol (E2) in cultured granulosa cells obtained from follicles about 26 hr after the initiation of the LH surge was restricted in small quantities, a marked increase in E2 production occurred in the presence of testosterone (T) (10(-6) M) as aromatizable substrate. The non-aromatizable androgen, 5 alpha-dihydrotestosterone (DHT) (10(-7) M, 10(-6) M), slightly enhanced E2 production and it did not inhibit T aromatization in these cells. By contrast, DHT did not increase E2 production in granulosa cells obtained from follicles 2-5 days before the LH surge. The results indicate that androgen can enhance the estrogen biosynthesis of granulosa cells obtained from follicles during the LH surge not only by acting as a substrate for aromatization but also by participating in some process of the estrogen synthesis. This effect of androgen was not clearly seen in granulosa cells obtained before the LH surge, suggesting that the response of granulosa cells to exogenous androgen varies with the stage of the cell differentiation.

Cells, Cultured↗
PubMed1988

[Studies on aldosterone RIA kit using the two antibody method].

Two antibody method of aldosterone RIA kit was investigated. This kit was measured directly without extracting the aldosterone. On fundamental studies, stability of standard curve, reproductivity, recovery test and dilution test were obtained good results. On clinical studies, the diurnal variation of serum aldosterone concentration in normal child and adult was correlated well to that of concentration of cortisol and ACTH. The concentration of three hormones was the highest in the early morning and it was the lowest in midnight.

Adrenocorticotropic Hormone↗
PubMed1988

Effects of arotinolol on hemodynamics and adrenergically induced renin release and renal vasoconstriction.

Effects of 5-[2-[(3-tert-butylamino-2-hydroxypropylthio)-4-thiazolyl]-2- thiophenecarboxamide hydrochloride (arotinolol, S-596) on hemodynamic and adrenergically induced renin release and renal vasoconstriction were investigated in pentobarbital anesthetized dogs. Arotinolol (1 mg/kg i.v.) decreased systemic blood pressure (SBP), heart rate (HR) and renin secretion rate without change in renal blood flow. Degree of hypotension induced by arotinolol and basal plasma renin activity prior to the injection of the drug showed significant correlation. Arotinolol (20 micrograms/min) produced significant suppression of renal nerve stimulation (RNS)-induced renin release and attenuated an increase in renal vascular resistance during RNS at 3 Hz. The same extent of inhibition in the renin secretion response to RNS was also obtained during the infusion of dl-propranolol (100 micrograms/min). The renal vasoconstriction induced by RNS and norepinephrine (NE) was inhibited dose-dependently during the infusion of arotinolol (10, 30 and 100 micrograms/min), phentolamine (3, 10 and 30 micrograms/min) or prazosin (1, 3 and 10 micrograms/min). Arotinolol and prazosin exerted a greater inhibitory effect on RNS- than NE-induced vasoconstriction, and the opposite was true of phentolamine. Arotinolol dose-dependently decreased SBP and HR in a dose range of 0.01 to 3.0 mg/kg. The greater reduction in HR was observed with arotinolol at a lower dose range (0.01 to 0.1 mg/kg) than with propranolol. Arotinolol produced larger reduction of SBP, and less increase in carotid, vertebral, renal and external iliac vascular resistances than propranolol. These results suggest that arotinolol posesses a- and beta-adrenoceptor blocking properties, which effectively contribute to the suppression of the adrenergically induced renin release and renal vasoconstriction, and to the hypotensive effect.

Adrenergic beta-Antagonists↗
PubMed1988

Nonimmunologic hydrops fetalis resulting from intrauterine human parvovirus B-19 infection: report of two cases.

Two cases of nonimmunologic hydrops fetalis associated with intrauterine human parvovirus B-19 infection are reported. In these cases, hydrops fetalis was diagnosed with ultrasound at 21 and 22 weeks' gestation after 10 or more days of maternal flu-like symptoms. The outcome was stillbirth in one case and neonatal death in the other. In both cases, intrauterine infection by human parvovirus B-19 was confirmed based on two findings: maternal serum positive for human parvovirus B-19 immunoglobulin M (IgM) antibody, and human parvovirus B-19 DNA detected in the fetal organs using Southern blotting and hybridization with a 32P-labeled probe. Laboratory tests on cord blood demonstrated a red blood cell count of 163 x 10(4)/microL, and nucleated red cells numbering 1267 per 50 white cells in the live-birth case. Histologic examinations of fetal tissues demonstrated leukoerythroblastic reaction in the liver and spleen, granular hemosiderin deposition in hepatocytes and Kupffer cells, and bilirubin deposition in the intercellular space in the liver. This evidence indicates that, in some fetuses with intrauterine human parvovirus B-19 infection, hydropic changes may be induced by the sudden decrease in oxygen-carrying capacity of the blood due to severe anemia caused by the infection.

Adult↗
PubMed1988

Inhibition by opioid agonists and enhancement by antagonists of the release of catecholamines from the dog adrenal gland in response to splanchnic nerve stimulation: evidence for the functional role of opioid receptors.

The aim of the present study is to examine how opioid agonists and antagonists modify the splanchnic nerve stimulation (SNS)-induced release of catecholamines from the dog adrenal gland in vivo, in an attempt to elucidate whether opioid receptors play a functional role in controlling catecholamine release. Output of epinephrine (EPI) and norepinephrine (NE) was determined from adrenal venous blood by using high-performance liquid chromatography with electrochemical detection. SNS (0.3, 1 and 3 Hz) produced increases in both EPI and NE output in a frequency-dependent manner. Leu-enkephalin (10-100 micrograms/kg i.v.) and morphine (10-100 micrograms/kg i.v.) attenuated the increase in EPI and NE output induced by 1 or 3 Hz of SNS without affecting the basal catecholamine output. A 25 to 40% reduction of the SNS-induced increase in catecholamine output was observed after the treatment with 100 micrograms/kg of leu-enkephalin or morphine. The increase in EPI and NE output induced by 1 and 3 Hz of SNS was enhanced markedly by naloxone (10-1000 micrograms/kg i.v.) and by naltrexone (10-1000 micrograms/kg i.v.). The SNS-induced increase in catecholamine output doubled after treatment with 100 and 1000 micrograms/kg of naloxone or naltrexone. Basal catecholamine output and the increase in output induced by 1 Hz of SNS were unaffected by naloxone or naltrexone. These results suggest that endogenously released opioid peptides inhibit the release of catecholamines by activating opioid receptors in the adrenal gland of the dog.

Adrenal Glands↗
PubMed1988

[Laboratory and clinical studies on cefotetan in respiratory tract infections].

Seventy five patients with respiratory infections, including 40 cases of acute pneumonia, 33 cases of secondary infection after chronic pulmonary diseases and 2 cases of pulmonary abscess, were treated with cefotetan (CTT, Yamatetan) by drip infusion in order to evaluate its clinical efficacy. The overall rate of effectiveness was 83.8%. CTT was examined comparatively with other beta-lactam antibiotics for antibacterial activity on clinically isolated strains of 3 major respiratory pathogens including Haemophilus influenzae, Branhamella catarrhalis and Streptococcus pneumoniae. Minimum inhibitory concentrations (MIC's) of CTT on H. influenzae were less than 3.13 micrograms/ml regardless of the production of beta-lactamase by these organisms. As to B. catarrhalis, CTT also exerted an antibacterial activity enough to control the proliferation of all the strains at a level of 1.56 micrograms/ml. Against S. pneumoniae, on the other hand, CTT exhibited the lowest activity of all the drugs tested but still showed MIC's of 3.13 micrograms/ml or less. Drip infusion of CTT at a dose of 2 g brought about an average maximum blood concentration of 342 +/- 25.7 micrograms/ml and an average half-life in blood of 2.48 +/- 0.41 hours Maximum sputum concentration of the drug, however, was variable among the cases tested, ranging from 0.40 to 1.80 micrograms/ml. Side effects of the drug were observed in 5 cases or 6.7%. Four of them had some allergic symptoms; i.e., pyrexia and eruption. One patient was especially diagnosed as possible drug-induced interstitial pneumonia during the treatment with the drug. The diagnosis was confirmed by transbronchial lung biopsy and lymphocyte blastogenesis by CTT in vitro. As to abnormal laboratory findings, blood transaminases were elevated during drug administration in 13 cases or 17.3%, but were reduced back to the normal level after the withdrawal of the drug.

Adult↗
PubMed1988

[Epidermoid cyst of the testis: a report of 2 cases].

We report two cases of intratesticular epidermoid cyst, one of which had ossification in the cyst. Two cases were treated by orchiectomy with high ligation of the cord under the diagnosis of testicular malignant tumor. Ultrasonographic examination revealed a well-defined solid mass with echogenic rim. The internal echo of the cysts were relatively homogeneous and almost similar to the surrounding normal testicular parenchyma in the echo level.

Adult↗
PubMed1988

[Immunohistochemical study of developing rat embryo--localization of vimentin, GFAP, neurofilament protein within rat embryo central nervous system].

The identification of intermediate filaments within immature cells is valuable as a means to investigate neuronal and glial differentiation. The purpose of this study is to investigate the time of appearance of neuron and glia within rat embryo by identifying cell-specific intermediate filaments. Pregnant rat were daily sacrificed from day 9-20 of pregnancy. Rat embryos were fixed with 100% ethanol and then we have made the paraffin section. We have stained the specimens for vimentin in accordance with ABC method and for GFAP in accordance with PAP method. We have performed Bodian stain. The neural plate of day 9 rat embryo is composed with vimentin positive immature cells which are disposed with pseudostratified arrangement. In midbrain of day 13 rat embryo, immature cells and their fibers are vimentin positive which are spanning from ventricular surface to marginal layer. NFP is detectable in immature cells and fibers of marginal layer. But GFAP positive cells and fibers are not identified in the same region. In anterior column of day 18 rat embryo, GFAP positive fibers are detectable. Summarizing of these results, we can display first: immature cells composing of neural plate are vimentin positive at day 9, second: NFP positive fibers and cells appear at day 13, third: NFP positive cells are vimentin positive, too, forth: GFAP positive fibers appear at day 18 and they are vimentin positive, too.

Animals↗
PubMed1988

[MRI findings of cervical cord injury. A case report of long-term follow-up].

A 63 year-old male, who sustained anterior cervical cord injury in a fall on his back during skiing, was consecutively examined by MRI from acute, up to the chronic stage. Right after the fall (2.5 hours later) the injured cord showed high intensity in T2 weighted images. This high intensity area stayed the same up to the chronic stage (6 months later). T1 weighted SE images showed no parenchymal change in the acute stage, but 3 months later a low intensity area appeared in the damaged cord. Thereafter, the injured cord exhibited localized low intensity on T1 weighted images, and high intensity on T2 weighted images, at subsequent MRI examinations. During the course of the examinations no significant neurological recovery was observed. Referring to the findings of our experimental cord injury studies, the high intensity in the T2 weighted images of the acute stage represents hemorrhagic necrotic tissue with edema, while those of the chronic stage suggest myelomalacia, and surrounding gliotic tissue. The low intensity in the T1 weighted images of the chronic stage reflects also this myelomalacia itself. We conclude that MRI of cervical cord injury is a useful diagnostic tool, not only delineating the level of the cord injury, but also aiding in the prognosis.

Follow-Up Studies↗
PubMed1988

A new perimetric color vision analyzer.

A new apparatus was developed for mapping the extrafoveal color vision, the perimetric color vision analyzer. A yellow test object with varying degrees of saturation is presented on a cathode ray tube color display in a random sequence at one of 10 points around the fixation spot. The background is a mosaic pattern consisting of gray spots of the same size and shape as the test object, with various luminances. Background patterns with or without a test object are presented alternately. The subject is instructed to press a key when he detects a yellow object in the background pattern. The luminance of the test object is in the same range as the background gray spots. Since the luminance of background spots is changed synchronously at random when the test object appears, the subject can detect the test object only by the difference in color saturation. The results show the color contrast sensitivity at every designated point in the central visual field. The clinical application of the perimetric color vision analyzer revealed extrafoveal color defects which could not be evaluated with conventional color vision tests. It also showed that in some chorioretinal and optic nerve disorders the topographic pattern of color contrast sensitivity disagrees with that of luminance contrast sensitivity measured with automated static perimetry.

Adult↗
PubMed1988

Radiosensitivity of late recurrences following radiotherapy of murine fibrosarcomas.

Radiosensitivity of late recurrent tumors which emerged after radiotherapy was investigated. Tumors observed were fibrosarcomas. Recurrences emerged in the irradiated area approximately 200 days after a 50% tumor control dose of radiation of 60Co gamma rays or mixed irradiation with fast neutrons and gamma rays. The recurrent and radiation-induced tumors were differentiated by karyotype analysis. Once transplanted into fresh mice, the recurrent tumors grew more slowly than the original tumor. Tumorigenicity of the late recurrences was lower than that of the original tumor. Radiosensitivity of the late recurrences, which was examined using methods to assess control, tumor growth delay, and colony forming assays, was significantly higher than that of the original tumor. D0 values of hypoxic tumor cells were significantly smaller in two of the three recurrences compared to the original tumor. Oxic cells, when irradiated in vitro, also showed smaller D0 values for the recurrent tumors than the original tumor. Hypoxic cell fractions were between 0 and 14% in the late recurrences and 10% in the original tumor. These results are consistent with the hypothesis that radiotherapy causes mutation of tumor cells which results in increased radiosensitivity of surviving tumor cells.

Animals↗