Biomedical subjects

T Satoh

Publications and source records attributed to T Satoh.

At least 1,135 records · Page 63Linked to original sources

PubMed1985

Experimental studies on myocardial glucose metabolism of rats with 18F-2-fluoro-2-deoxy-D-glucose.

The myocardial uptake of 18F-FDG was investigated under various conditions, and compared with brain and tumor uptake as a function of blood glucose level. The uptake by the heart of normal feeding rats was rapid and remained essentially unchanged up to 2 h after 18F-FDG injection, approximately 3%-4% dose/g tissue. On the other hand, the myocardial uptake of fasted rats was significantly lower than that of control rats throughout the course of the study, and it was about 0.3%-0.4% dose/g tissue. Myocardial uptake of 18F-FDG was relatively constant at glucose levels under about 120 mg/100 ml and increased steeply at higher blood glucose levels. In contrast, brain uptake decreased linearly with increasing levels of blood glucose, revealing a strong negative correlation between brain uptake of 18F-FDG and blood glucose levels. The tumor uptake pattern remained relatively unchanged, irrespective of blood glucose levels. It was revealed that the glucose demands of brain, heart, and tumor were entirely different. After a glucose load, the myocardial uptake of fasted rats increased only slightly from 0.4% to 0.6% dose/g tissue, in spite of transitional hyperglycemia. In contrast, insulin caused myocardial uptake to increase extraordinarily, although it caused a decrease in blood glucose levels.

Animals↗

PubMed1985

A sensitive assay for chicken glutamyltransferase.

The optimal conditions required for measuring chicken glutamyltransferase were examined to obtain a sensitive quantitative assay method for the enzyme. This method has made possible the determination of the enzyme activity in various tissues.

Adenosine Diphosphate↗

PubMed1985

Experimental tongue carcinoma of rats induced by oral administration of 4-nitroquinoline 1-oxide (4NQO) in drinking water.

Oral administration of 0.001% 4NQO in drinking water resulted in a high incidence of tongue carcinoma in rats. In other major organs, tumor induction was rarely observed. The most frequent site of tongue carcinoma was the dorsum. No metastases were found. Changes observed included carcinoma in situ and invasive carcinoma. Carcinoma in situ showed erosion, leukoplakia, and a gross papillary appearance. Histologically, most carcinomas in situ showed full-thickness alteration of epithelium. Some carcinomas in situ in papillary lesions showed slightly less than full-thickness alteration of epithelium, exhibiting downward, well-differentiated growth. Invasive carcinomas were either endophytic or exophytic. Histologic grading of invasive carcinoma varied from highly to poorly differentiated. The method described offers a new experimental animal model of tongue carcinoma.

4-Nitroquinoline-1-oxide↗

PubMed1985

Effects of naloxone and chlordiazepoxide on lateral hypothalamic self-stimulation in rats.

Lateral hypothalamic self-stimulation behavior of rats in an operant chamber was investigated under the treatments of the first injection of naloxone (5 mg/kg) or saline followed by the second injection of chlordiazepoxide (4 mg/kg) or saline. Both inhibitory effect of naloxone and facilitatory effect of chlordiazepoxide on self-stimulation response were statistically significant, but the interaction between the two effects was not obtained. The results indicate that the facilitatory effect of chlordiazepoxide upon self-stimulation is independent of endogenous opioid system. Further, the obtained effect of naloxone was discussed in terms of interaction of the drug with aversive, rather than rewarding, component of self-stimulation.

Animals↗

PubMed1985

Cerebrospinal fluid dynamics in traumatic intracerebral pneumocephalus evaluated with computed tomographic cisternography.

Cerebrospinal fluid dynamics in a case of traumatic intracerebral pneumocephalus are evaluated with metrizamide computed tomographic cisternography. Accumulation of metrizamide into the air cyst through the ventricular system is due to transependymal penetration, which can be explained by the mechanism of the pressure gradient from the ventricle towards the air cyst.

Adolescent↗

PubMed1985

Two types of rostroventral medulla neurons projecting to the trigeminal spinal nucleus as differentiated by the response to antidromic activation and the histological location.

A population of neurons in the rostroventral medulla, which send their axons to the subnucleus oralis of the trigeminal spinal nucleus of rats, could be differentiated into two types on the basis of their location and the variability of antidromic latency during repetitive stimulation at 10 Hz. Type A neurons were mostly located in the raphe magnus and were activated antidromically with a relatively long latency, which gradually increased during repetitive stimulation. By contrast, type B neurons were located in the medial portion of the gigantocellular reticular nucleus, and responded with a relatively short, stable antidromic latency.

Animals↗

PubMed1985

Stimulus-response relation of tooth pulp units in rat trigeminal nucleus.

Electrical stimulation of the rat tooth pulp evokes a slow mass potential (SMP) in the trigeminal spinal nucleus. Single units in the SMP field were examined for their stimulus-response relation. The response profile of most single units differed from that of background SMPs in that the former tended to give a greater gradient or exponent when they were approximated by linear or power function, respectively. Most of single units with a short and stable latency could be described rather well by power function, while a majority of units with a longer and unstable latency had a relatively wide dynamic range to varied stimulus intensities and could be approximated more closely by linear function.

Animals↗

PubMed1985

Urinary tract infection in oliguric patients with chronic renal failure.

We studied 182 patients with chronic renal failure by urinalysis and urine cultures. Of the patients 27 per cent had significant bacteriuria (more than 10(5) per ml.), 38 per cent had significant pyuria (more than 10 white blood cells per high power field), 19 per cent had urinary tract infection and 7 per cent had symptomatic urinary tract infection. All 12 patients with symptomatic urinary tract infection had significant bacteriuria and 11 had significant pyuria, while 1 had 5 to 10 white blood cells per high power field. Incidences of urinary tract infection differed depending on the primary renal disease (12, 13, 41 and 67 per cent for chronic glomerulonephritis, diabetic nephropathy, polycystic kidney and chronic pyelonephritis, respectively). Among the patients with chronic glomerulonephritis no significant differences were seen in frequencies of bacteriuria and urinary tract infection between male and female patients or between those who did and did not undergo hemodialysis. Also, no significant correlation was seen between bacteriuria and daily urine output but pyuria was significantly more frequent in oliguric patients or those on hemodialysis.

Anuria↗

PubMed1985

Sex difference in subunit composition of hepatic glutathione S-transferase in rats.

The activities of hepatic cytosolic glutathione S-transferases (GSTs) towards 1,2-dichloro-4-nitrobenzene in male rats were higher than those in females, however, the enzyme activities towards 1-chloro-2,4-dinitrobenzene were not significantly different between the two sexes. SDS-PAGE analysis of GSTs purified from male and female rat hepatic cytosols by affinity column chromatography showed that there was a significant difference in the subunit composition between the two sexes. With regard to the several isozymes of GSTs in male and female rats, isozymes with basic and neutral/acidic isoelectric points were separated into seven molecular species by chromatofocusing. These sex differences in the quantitative proportions of GST isozymes were also confirmed by immunotitration using anti-GST-BL and -AC antibodies. On the other hand, glutathione peroxidase (GSH-Px) activities in rat hepatic cytosol towards hydrogen peroxide and cumene hydroperoxide were markedly higher in females than in males. Of the two types of GSH-Px, selenoenzyme (Se-GSH-Px) and the Se-independent enzyme (non-Se-GSH-Px), the former was found to be mainly responsible for the sex difference in the enzyme activities. Moreover, the GSH-Px activity of GSTs, non-Se-GSH-Px, was also higher in females than that in males. Since GST isozymes of the BL type are known to possess GSH-Px activity towards cumene hydroperoxide, the increased activities of non-Se-GSH-Px in the female hepatic cytosol seemed to be mainly due to the increased transferase activities of the isozymes, GST-L2 and -BL.

Animals↗

PubMed1985

Clinical appearance of orofacial infections of odontogenic origin in relation to microbiological findings.

Fifty-eight patients with acute orofacial infections of odontogenic origin were classified into two groups with respect to the severity of infection. A total of 174 anaerobic and 22 aerobic bacterial strains were isolated. Anaerobic gram-negative rods were isolated more frequently from the patients with severe infections than from the patients with infections judged as mild (P less than 0.05). The occurrence of Fusobacterium nucleatum especially appeared to be associated with the severity of the infections (P less than 0.05). Penicillin resistance among the anaerobes was rarely found, while resistance to erythromycin was a common finding. All aerobic and anaerobic bacteria were susceptible to clindamycin, and all obligate anaerobic bacteria were susceptible to nitroimidazoles.

Adult↗

PubMed1985

Fisher's syndrome following trigeminal herpes zoster.

A case of Fisher's syndrome associated with trigeminal herpes zoster is reported for the first time. Retrograde propagation of the virus to the brainstem through the trigeminal root was thought to be the most probable pathogenic mechanism. We provide additional evidence suggesting that the focus of Fisher's syndrome is in the brainstem.

Adult↗

PubMed1985

Significance of gonad and renal prostaglandin E2 in the antihypertensive effect of pindolol in spontaneously hypertensive rats.

The effect of gonadectomy on the antihypertensive action of pindolol in male spontaneously hypertensive rats (SHR) was investigated. And we also examined the relationship between the antihypertensive effect of this drug and the renal prostaglandin E2 (PGE2) level. In gonadectomized SHR, the reduction of blood pressure was not observed by the oral administration of pindolol, although the drug exhibited a marked antihypertensive activity in sham operated SHR. Urinary PGE2 in sham operated SHR was increased following the administration of pindolol, but not in gonadectomized SHR. Similar results were obtained in the experiments using Wistar rats. The PG synthesis inhibition induced by indomethacin suppressed the antihypertensive action of pindolol. Results in the present study suggest that renal PGs, particularly PGE2, are involved in the antihypertensive mechanism of pindolol, and that male gonad takes part in the regulation of the stimulation of the renal PGE2 producing system induced by pindolol.

Animals↗

PubMed1985