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Biomedical subjects

H Satoh

Publications and source records attributed to H Satoh.

At least 811 records · Page 45Linked to original sources
PubMed1986

On the mechanism by which changes in extracellular pH affect the electrical activity of the rabbit sino-atrial node.

1. The effect of altering the extracellular pH (pHo) on the electrical activity of the isolated rabbit sino-atrial (s.a.) node was studied using the two-micro-electrode voltage-clamp technique. 2. Alkalinization of the perfusate increased the maximum rate of rise and amplitude of the nodal action potential, and also the frequency of spontaneous beating of the s.a. node; acidification produced opposite effects. 3. A change in the extracellular pH from a value of 6.5 to 8.5 caused increases of the maximal conductance for both the slow inward current and the steady-state outward current systems without affecting the gating processes of the channels. 4. H+ could modify the electrical activity of s.a. nodal cells, not through altering the membrane surface potential but through the protonation of the ionic channels themselves. From the titration curves, the apparent pKa values for the slow inward current and the steady-state outward current were estimated to be 6.4 and 6.0, respectively.

Action Potentials↗
PubMed1986

Electrophysiological effects of procaine in rabbit sino-atrial node cells.

Effects of procaine (50-500 micrograms/ml) on membrane potential and currents were investigated using a two microelectrode-voltage clamp technique. Procaine reduced the action potential amplitude (APA), the maximum diastolic potential and the maximum rate of depolarization (Vmax) in a dose-dependent manner. At the same time, the action potential duration and the cycle length were prolonged. In voltage clamp experiments, procaine (50 micrograms/ml) did not affect the slow inward current (Isi), but reduced the time-dependent outward current (Ik). At concentrations higher than 100 micrograms/ml, procaine reduced both currents and the inward current activated by hyperpolarization in a dose-dependent manner. In 7 of 20 specimens, a low concentration of procaine (50 or 100 micrograms/ml) increased Isi which enhanced the Vmax and APA, but did not increase Ik. Procaine did not affect the steady-state inactivation of Isi (f infinity) and the activation of Ik (p infinity). The results suggest that the depressions of currents induced by procaine are due to a reduction in conductances of the current systems.

Action Potentials↗
PubMed1986

[Sorting of living and dead cells by flow cytometry--staining principle and basic experiment].

Simultaneous staining with fluorescein diacetate (FDA) and propidium iodide (PI) is described for use in the identification of living cells and dead cells. FDA passes through living cell membranes and is hydrolyzed by intracellular esterase to produce fluorescein. Fluorescein accumulates inside the cell and emits green. PI passes through dead cell membranes and intercalates with DNA to form a bright red fluorescent complex. Living cells and dead cells are easily identified on the cytograms by flow cytometry. In cases of normal uterine squamous epithelium, white blood cells are viable, while superficial type cells and intermediate type cells are dead.

Animals↗
PubMed1986

[Establishment and characterization of the cell line derived from low differentiated adenocarcinoma of the endometrium].

A new human carcinoma cell line (HEC-1), which was derived from low differentiated adenocarcinoma of the endometrium, has been established. Cells from tumor tissues grown in athymic mice were cultured in minimal essential medium supplemented with 20% fetal calf serum. Contaminated mouse fibroblasts were removed from the culture by the absorption of anti-mouse serum. Continuous cell growth (doubling time: 51.6 hrs) could be observed during 64 passages. The cultured cells appeared monolayer and the cellular arrangement was a pavement-like pattern. The morphology of cells was analogous to the one of adenocarcinoma cells. The modal number of chromosomes of the original tumor cells were 46. The t. dic (1; 16)(p21; q24) marker which had been identified as the clonal abnormality in the original tumor cells, was also observed consistently in cultured cells, though the loss of chromosome 19 was disappeared during the passage. This suggested that the rearrangements of the long arm of chromosome 1 played an important role for the endometrial carcinogenesis.

Adenocarcinoma↗
PubMed1986

[Histological and endocrinological studies on the oocyte factor in the cumulus oophorus formation].

The mechanism of cumulus oophorus formation with the follicular growth has been little observed. In order to make clear about it, the possible existence of a granulosa cell growth factor (GGF) in the oocyte was investigated by using the Mitotic Index (MI) (%0) of granulosa cells (GC) in human antral follicles. In each follicle, GC were divided into two groups, cumulus and mural GC, on the basis of the distance from the oocyte. The MI of cumulus GC was 8.2 +/- 0.5 (M +/- SE), constantly high in value with no relation to the follicular diameter, and two fold higher than that of mural GC, 4.7 +/- 0.4 (p less than 0.001). In general, Estradiol (E2) is well known as a granulosa cell growth factor. Hence, we investigated whether oocyte had E2 to know how E2 participates in the cumulus oophorus formation, by using the enzyme histochemical study. E2 content of the oocytes measured by Multi-Micro-Spectrophotometer in preantral and small antral follicles in which GC actively proliferate were 13.6 +/- 0.8% and 10.2 +/- 0.7% respectively, and higher than that of in large antral follicle, 7.6 +/- 1.0%. To examine the origin of E2 in oocytes, oocytes, GC and follicular fluid were measured using porcine ovaries. E2/protein of oocytes was 34.1 +/- 6.4 (pg/mg. prot) and that of GC was 10.2 +/- 2.8. It means that the origin of E2 may be from the oocyte itself. These results suggest, E2 in oocytes is estimated to be one of the oocyte factor to stimulate the granulosa cell proliferation and E2 plays a crucial role in the cumulus oophorus formation.

Adult↗
PubMed1986

[Pharmacokinetic and clinical studies on cefuzonam in the pediatric field].

A multi-center open study was conducted to investigate cefuzonam (L-105, CZON), a newly developed cephalosporin from pharmacokinetic, bacteriological and clinical aspects, in the pediatric field with the participation of 17 institutions and their related facilities. The results are summarized as follows. Serum concentrations and urinary excretion. The pharmacokinetics in pediatric patients was investigated with a dose of 20 mg/kg, via one shot intravenous injection or intravenous drip infusion over 1 hour. The results were nearly the same as those in adult patients. Mean serum concentrations 5 minutes after one shot intravenous injections were: 52.8 micrograms/ml with the dosage of 10 mg/kg, 135 micrograms/ml with 20 mg/kg, and 317 micrograms/ml with 40 mg/kg, and T1/2 beta's for the 3 dosages were 1.07 hours, 0.91 hour, and 1.01 hours, respectively. With 1-hour intravenous drip infusion, mean serum concentrations at the end of infusion were: 22.4 micrograms/ml with 10 mg/kg, 46.3 micrograms/ml with 20 mg/kg, 72.5 micrograms/ml with 40 mg/kg, and 69.2 micrograms/ml with 50 mg/kg, and T1/2 beta's for these dosages were 1.31 hours, 1.45 hours, 0.84 hour, and 0.66 hour, respectively. In 6 hours after administration of CZON, urinary excretion rates were 43.5-51.4% for one shot intravenous injections of 10-40 mg/kg, and 42.7-58.6% for 10-50 mg/kg drip infusions. Concentrations in cerebrospinal fluid Penetrations into cerebrospinal fluids in patients with purulent meningitis achieved levels of 2.80-6.40 micrograms/ml with the administration of CZON at 100 mg/kg in acute cases of within 6 days after onset. When the administration of the drug was done at the earlier stage, the greater penetration occurred. However, rates of penetration were 3.10% to 5.03% within 4 days after a drug administration, thus, the penetration was not thought to be as good as other beta-lactam agents which achieve higher penetration rates. Clinical results Of 407 cases treated with CZON, 18 cases were excluded from the statistical analysis. The remaining 389 cases plus 8 cases each of which had 2 complicated diseases, with a total of 397, were statistically analyzed for the clinical effectiveness of this drug against various infections. The efficacy was evaluated as "good" or "excellent" in 248 out of 266 cases from which pathogens were isolated, for an efficacy rate of 93.2%. The efficacy rate was 88.5% for 131 cases for which pathogens were unidentified, thus no statistically significant difference was noted between the 2 groups.(ABSTRACT TRUNCATED AT 400 WORDS)

Ceftizoxime↗
PubMed1985

Gastric mucosal protection by spizofurone.

The protective effect of spizofurone (AG-629) on the rat gastric mucosa was studied in the presence of various stimuli. Spizofurone given orally markedly inhibited gastric lesions induced by ethanol (ED50 = 6.5 mg/kg). Spizofurone inhibited ethanol-induced gastric lesions even when administered intraperitoneally (i.p.), but the onset of action after oral administration was shorter. Spizofurone given orally or i.p. in a dose range of 25-200 mg/kg inhibited indomethacin-induced gastric antral ulcers in re-fed rats. Furthermore, spizofurone potentiated the inhibitory effect of prostaglandin E2 on indomethacin-induced gastric antral ulcers. Spizofurone given i.p. prevented a decrease in potential difference and the formation of gastric lesions induced by intragastric instillation of 30 mM aspirin in 0.1 N HCl. Spizofurone given i.p. inhibited the increase in net fluxes of H+ and Na+ caused by intragastric instillation of 15% ethanol in 0.1 N HCl. These findings indicate that spizofurone, like prostaglandin E2, exerts gastric mucosal protection and even potentiates the anti-ulcer effect of prostaglandin E2. The gastric mucosal protection by spizofurone is ascribed in part to preservation of the mucosal barrier.

Animals↗
PubMed1985

Evaluation of treatment for gastric cancer with liver metastasis.

In 161 cases of gastric cancer with liver metastasis but without peritoneal dissemination, evaluations were executed to find effective treatment. The most favorable results with best prognosis were obtained in the group receiving gastrectomy + hepatectomy + chemotherapy, followed by gastrectomy + chemotherapy, and gastrectomy alone. The most unfavorable outcome was in nonresected cases. Chief chemotherapy to be used after gastrectomy was FML (5-fluorouracil (5-FU) + mitomycin C [MMC] + lentinan) continuous intra-arterial infusion. Hepatectomy was found to be effective as an active measure for tumor reduction in cases of liver metastasis so far as the metastatic lesions are only a few scattered ones in both lobes.

Adult↗
PubMed1985

Spizofurone (AG-629) increases gastric mucosal blood flow in dogs: a possible mechanism of its anti-ulcer effect.

The effect of spizofurone (AG-629), a new anti-ulcer agent, on gastric mucosal blood flow was investigated in anesthetized dogs and the effects were compared with those of prostaglandin E2. Intravenous administration of spizofurone in doses of 15 and 30 mg/kg caused a dose-related increase in gastric mucosal blood flow. Spizofurone (1-10 mg/ml) given intragastrically for 15 min produced a sustained increase in gastric mucosal blood flow in a concentration-dependent manner; with 3 mg/ml there was about a 50% increase in gastric mucosal blood flow at the peak and a 2 h duration of action. The mode of action of spizofurone was similar to that of prostaglandin E2. The reduction in the gastric mucosal blood flow as induced by indomethacin was markedly improved by spizofurone. The topical action of spizofurone was confirmed in an in situ experiment using a stomach flap fixed to a lucite chamber. These results indicate that spizofurone increases gastric mucosal blood flow after systemic and topical administration, and this increase in gastric mucosal blood flow would account for the anti-ulcer effects of this drug.

Aminopyrine↗
PubMed1985

Effects of calcium antagonists and calmodulin inhibitors on angiotensin II-induced prostaglandin productions in the isolated dog renal arteries.

Angiotensin II markedly potentiated both PGE2 and PGI2 productions in the isolated dog renal arteries. This angiotensin II-induced response was significantly reduced by the treatments of EGTA and calcium antagonists such as verapamil, nifedipine and 8-(N,N'-diethylamino)-octyl-3,4,5,-trimethoxybenzoate (TMB-8). Calmodulin inhibitors, trifluoperazine and W-7 also inhibited the angiotensin II-induced PG productions while an inactive analogue of W-7, W-5 did not have any effect. The results suggest that angiotensin II may enhance the intracellular Ca2+ level through the influx of extracellular Ca2+ and then, calmodulin activated with Ca2+ will stimulate both PGE2 and PGI2 productions via its activation of phospholipase A2 in the dog renal arteries.

6-Ketoprostaglandin F1 alpha↗
PubMed1985

A case report of a patient with retinoblastoma and chromosome 13q deletion: assignment of a new gene (gene for LCP1) on human chromosome 13.

Retinoblastoma (Rb) occurs in hereditary, non-hereditary, and chromosomal deletion forms and the locus for the Rb gene (Rb-1) is closely linked to the locus for esterase D (ESD) assigned to the chromosome 13q14.11. We describe a patient who was predicted to have Rb from the genetic analysis of the chromosome and ESD phenotype. Furthermore, the gene for lymphocyte cytosol polypeptide with molecular weight of 64,000 (LCP1: McKusick catalogue No. 15343, 1983) was assigned to chromosome 13 by deletion mapping. A 3-month-old female had many characteristics of chromosome 13q-syndrome, including dolichocephaly, epicanthus, ptosis, depressed nasal bridge, micrognathia, short webbed neck, and short fifth fingers with clinodactyly and single crease. The karyotype of the patient was 46,XX,del(13) (q14.1-q32), though both the parents had normal karyotypes. As expected, the phenotype of ESD derived from one of the parents, the father in this case, was not detected in peripheral blood lymphocytes by two-dimensional gel electrophoresis (two-DE), indicating that ESD from the father was deleted in the abnormal chromosome 13. The possibility of paternity was calculated to be 0.996 based on the data using 22 genetic markers. Bilateral retinoblastomas could be diagnosed by ophthalmologic examinations before the manifestation of any clinical signs of the tumor and immediately intensive care was taken. In addition, the phenotype of LCP1 derived from the father was not expressed in the lymphocyte proteins from the patient. These data indicate that the gene for LCP1 (LCP1) is located in the region q14.1-q32 of chromosome 13 and may be a useful genetic marker for preclinical diagnosis of Rb.

Blood Proteins↗