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T Oguchi

Publications and source records attributed to T Oguchi.

At least 127 records · Page 7Linked to original sources
PubMed1986

[The development of the seizure caused by amygdaloid kindling in hemispherectomized cats].

In our present experiment, we intend to compare the hemispherectomized cats with the intact ones on the time latency for the completion of the kindling effect as well as on the developmental pattern of the clinical seizure manifestation. Ten cats weighing from 2.0 to 2.5 kg aged one year were used. Among them, five cats were used for normal controls. Electrodes were implanted in the dorsal hippocampus, the lateral amygdala and the cortical surface (frontal and occipital) of the right hemisphere under the intraperitoneal pentobarbital administration. One or two week after implantation of the electrodes, the left cerebral hemisphere was totally ectomized in a block including the subcortical structures such as amygdala, hippocampus, thalamus and hypothalamus down to the colliculus superior. One month following the left hemispherectomy, the cats were electrically stimulated daily at the after-discharge threshold intensity in the right lateral amygdala. All the examined cats was further stimulated five more times after they had reached the final stage of seizure. The five kindled cats reached the final stage of generalized convulsive seizures in 6, 10, 8, 10 and 3 times respectively (7.4 +/- 3.0 times; mean +/- SD). The time latency for the completion of kindling effect of the operated cats was significantly shorter than that observed in the control animals (21.0 +/- 5.5 times; n = 5, p less than 0.01). The after-discharge threshold intensity was from 200 to 600 microA and the generalized seizure triggering threshold intensity was from 100 to 500 microA. The average of after discharge duration in the final stage of seizure was 71.5 +/- 1.82 sec.(ABSTRACT TRUNCATED AT 250 WORDS)

Amygdala↗
PubMed1984

The E. coli K-12 chromosome flanked by two IS10 sequences transposes.

Transposon are commonly found among prokaryotes and usually range up to 20 kilobases. In this study, we were interested to determine whether a larger DNA segment could transpose. We observed that the E. coli K-12 chromosome, 4,000 kilobases in size, when flanked by two IS10 sequences, could transpose to pACYC177 at a frequency of 10(-8) per cell per generation. We suggest that this transposition event occurs independently of the size and without duplication of the entire DNA sequence flanked by the IS10 elements.

Chromosomes, Bacterial↗
PubMed1984

Does Tn10 transpose via the cointegrate molecule?

It has been well established that Tn3 and its relatives transpose from one replicon to another by two successive reactions: formation of the cointegrate molecule and resolution from it. Whether or not the 9300 base pair tetracycline resistance transposon Tn10 transposes in the same manner as Tn3 was investigated by two methods. In the first method, lambda 55, a lambda phage carrying Tn10 was lysogenized in an Escherichia coli strain carrying a Tn10 insertion; the phage has a deletion in attP, hence it was lysogenized in a Tn10 sequence in the E. coli chromosome by reciprocal recombination. The chromosomal structure in these lysogens is equivalent to the Tn10-mediated cointegrate molecule of lambda and the E. coli chromosomal DNA. The stability of the cointegrate molecule was examined by measuring the rate of excision of lambda from the host chromosome, and was found to be stable, especially in a Rec- strain. Because of this stability, the cointegrate molecule should be accumulated if Tn10 transposes via the cointegrate molecule. Then, we examined the configuration of products made by transposition of Tn10 from lambda 55 to the E. coli chromosome. The cointegrate molecule was found in products of Tn10 transposition in a Rec+ strain at a frequency of 5% per Tn10 transposition, but this molecule could not be found in a Rec- strain. Since transposition of Tn10 was recA-independent, absence of the cointegrate molecule formed in a RecA- strain strongly suggested that the cointegrate molecule is not an obligatory intermediate of transposition of Tn10.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteriophage lambda↗
PubMed1981

Analysis of flagellar genes in Pseudomonas aeruginosa by use of Rfla plasmids and conjugations.

Over 300 flagellar mutants were isolated in Pseudomonas aeruginosa PAO. R-prime plasmids carrying segments of bacterial chromosome which can complement the mutant phenotypes were isolated by means of plasmid R68.45. Among the R-prime plasmids, pMT6 complemented 167 out of 307 mutants examined, and pMT19 complemented the remaining 140 mutants. We found no mutant which was complemented by both of these plasmids. Hence, the flagellar genes were divided into two clusters by these two plasmids, namely, region I on pMT19 and region II on pMT6. By FP5- and R68.45-mediated conjugation, these two regions were located on the P. aeruginosa PAO chromosome with an order of puuF--region I--region II--oru-325.

Chromosome Mapping↗
PubMed1979

Comparison of efficacy of amoxapine and imipramine in a multi-clinic double-blind study using the WHO schedule for a standard assessment of patients with depressive disorders.

A multi-clinic double-blind controlled study on amoxapine in comparison with imipramine, using the WHO Schedule for a Standard Assessment of Patients with Depressive Disorders, was performed and the data were analyzed with 111 patients. The assessment of severity of illness and overall improvement indicated clearly the superiority of the antidepressive effect of amoxapine to that of imipramine. The onset of antidepressive effect of amoxapine was clearly more rapid than that of imipramine, and in more than half of the patients in the amoxapine group the improvement was seen within four days following the drug administration. Amoxapine was superior to imipramine in terms of safety and usefulness. The side-effects due to amoxapine appeared less frequently and were less serious than with imipramine. The difference between amoxapine and imipramine was especially remarkable for hypotensive effect. The antidepressive effect of amoxaphine was superior to that of imipramine for almost all symptoms and signs. Amoxapine displayed an especially remarkable effect on psychomotor retardation, depressive feeling, anxiety and tension, somatic complaints and sleep disturbance.

Amoxapine↗
PubMed1979

Separation of mouse T cell subsets by a fluorescent activated cell sorter using fluorescence-labeled peanut agglutinin.

Nylon non-adherent spleen T cells obtained from concanavalin A-injected mice were labeled with fluorescein-labeled peanut agglutinin and separated into peanut agglutinin-positive (PNA+) cells and peanut agglutinin-negative (PNA-) cells by a fluorescent activated cell sorter. PNA+ cells were found to exert marked suppressive effect on primary anti-sheep red blood cells antibody response, but PNA- cells did not affect the antibody response. From these results and from the sugar-binding specificity of PNA, suppressor T cells are supposed to possess abundant galactosyl residues exposed on the cell surface, which are not masked by sialyl residues.

Animals↗
PubMed1976

Action of enpiprazole on emotional behavior induced by hypothalamic stimulation in rats and cats.

Action of enpiprazole on emotional behavior elicited by hypothalamic stimulation in rats and cats was investigated and comparisons were made with effects of diazepam. Two behavioral patterns were elicited by stimulation of the postero-medial part of the hypothalamus in rats: a food-carrying response beginning with exploratory movement and an analogue of fear. Enpiprazole frequently changed the food-carrying response into food-taking response and occasionally analogues of fear into food-carrying and /or food-taking responses. Thresholds for these behaviors were also elevated. Diazepam showed the same effects on the thresholds as enpiprazole, having but little effect on the behavioral patterns. In cats, enpiprazole evelvated the thresholds for affective-defensive responses induced by hypothalamic stimulation in 6 of 8 cases, but lowered them in 2 cases. This suggests that enpiprazple has a 'biphasic effect' in the central nervous system. By contrast,diazepam consistently elevated thresholds. Comparing the action of enpiprazole with that of diazepam it can be presumed that the former is a different type of anxiolytic drug than the latter.

Animals↗
PubMed1975

Temporary expression of flagellar phase-1 in phase-2 clones of diphasic Salmonella.

Diphasic Salmonella strains, Salmonella typhimurium TM2, S. abony SW803 and their derivatives differing in flagellar shape and antigen type, were found to produce copolymer segments of phase-1 and phase-2 flagellins among flagella in phase 2, except for a strain which is non-flagellate in phase 1. The copolymer segments were not detected in phase-1 clones of any of the strains. The wave-forms of the copolymers are homologous with those of the copolymer filaments obtained by in vitro reconstitution of the corresponding phase-1 and phase-2 flagellins. Thus, in the mutant producing normal flagella in phase 1 and straight ones in phase 2, copolymer segments with curly or small waves appear among the straight filaments. Formation of the copolymers was attributed to temporary derepression of the structural gene for phase-1, flagellin, HI, in phase 2. Copolymerization occurred in a fraction of the phase-2 cell population at late exponential and early stationary phase in nutrient broth cultures. When a phase-2 cell was temporarily derepressed, the copolymers formed almost simultaneously in every growing flagellar filament of the cell. Their formation continued for a short period until the supply of phase-1 flagellin was exhausted after re-establishment of repression. This period was estimated to be 7-7 min on average, fluctuating between 4 and 13 min in a cell population of a straight flagellar mutant whose generation time was 55 min in late exponential phase.

Bacterial Proteins↗