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J Ito

Publications and source records attributed to J Ito.

At least 289 records · Page 16Linked to original sources
PubMed1987

[Experimental study on the control of cisplatin-induced emesis in dogs].

In order to search for methods of controlling cisplatin-induced emesis, a series of experiments were performed with dogs. Cisplatin was administered i.v. to dogs at three-day intervals, and the number of emetic episodes and latency period to the first episode following injection were examined. The dose of cisplatin was 0.3mg/kg at the first injection, and thereafter square root 2-fold higher doses than the preceding ones were injected up to a maximum of 2.4 mg/kg. Emesis was observed from 0.42 g/kg. The number of emetic episodes increased with escalation of the dose up to 0.85 mg/kg, but decreased at higher doses. On the other hand, the latency period shortened with increase of the dose up to the highest one. From these results, the latency period is concluded to be a reliable parameter for evaluating the emetic activity of cisplatin and the efficacy of anti-emetics. The anti-emetic effect of vagotomy, ethyl amino-benzoate or metoclopramide was then examined. When 1 mg/kg of cisplatin was administered i.v., mean values of latency period and the number of episodes in dogs of a control group were 200 minutes and 20 times, respectively. In vagotomized dogs, no emesis was observed. When ethyl amino-benzoate was administered p.o. at doses of 12, 24 and 48 mg/kg 30 minutes before and 90 minutes after cisplatin injection, the number of episodes decreased to between 8 and 4.3 times, but the latency period was not prolonged. When s.c. injections of 1 mg/kg metoclopramide were combined with cisplatin in a similar manner to ethyl amino-benzoate, the latency period was prolonged up to 343 minutes, and the number of episodes decreased to 2.7 times. These results suggest that the peripheral autonomic nervous system is involved in the mechanism of emesis induction by cisplatin. Finally, the anti-emetic effect of metoclopramide was examined using the following administration schedules of cisplatin: a single i.v. injection of 3.75 mg/kg and daily i.v. injections of 1.25 mg/kg for three days. Metoclopramide showed a superior anti-emetic effect in the latter schedule, when the dose of 2 mg/kg was given i.v. 30 minutes before and 90 and 210 minutes after the cisplatin injection.

Analysis of Variance↗
PubMed1987

The Turner syndrome: cognitive deficits, affective discrimination, and behavior problems.

Individuals with sex chromosomal anomalies are known to be at increased risk for learning problems and in some cases social or behavioral problems. Girls with an absent or structurally abnormal second sex chromosome (the Turner syndrome) have been found to have cognitive problem solving deficits and immature, inadequate social relationships. The present study attempted to link cognitive and social problems by assessing the girls' ability to process affective cues. 17 girls with karyotypes consistent with a diagnosis of Turner syndrome were compared to a group of 16 short-stature girls of comparable age, verbal intelligence scores, height, and family socioeconomic status on the Affective Discrimination Task, which required interpretation of affective intention from facial expression. The results revealed that the Turner syndrome girls were less accurate at inferring facial affect than the short-stature controls. Analyses revealed that the Turner syndrome girls performed more poorly on spatial, attentional, and short-term memory cognitive tasks and had more psychosocial problems than the short-stature controls. Ability to discriminate facial affect may be another area of cognitive weakness for girls with the Turner syndrome and may underlie the psychosocial problems found in this sample.

Adolescent↗
PubMed1986

Nucleotide sequence of Bacillus phage phi 29 genes 14 and 15: homology of gene 15 with other phage lysozymes.

The nucleotide sequence of Bacillus phage phi 29 genes 14 (g14) and 15 (g15) have been determined and shown to encode proteins with molecular weights of 15,014 and 28,022, respectively. The g14 open reading frame (ORF) was confirmed by sequencing a sus14(1241) mutant. Gene product 15 (gp15) has considerable homology with Salmonella phage P22 lysozyme and lesser homology with Escherichia coli phage T4 lysozyme. Putative translation signals are identified. In addition, the role of a previously described promoter, B2, is discussed.

Amino Acid Sequence↗
PubMed1986

Beta-receptor involvement in locus coeruleus-induced inhibition of spinal trigeminal nucleus neurons: microiontophoretic and HRP studies.

Microiontophoretic and HRP studies were performed on cats anesthetized with alpha-chloralose to determine whether or not the locus coeruleus (LC)- and noradrenaline (NA)-induced inhibition of relay neurons in the subnucleus oralis of the spinal trigeminal nucleus (STN) is mediated by beta-adrenergic receptors. The inhibition of orthodromic spike generation upon intracranial trigeminal nerve stimulation by LC conditioning stimulation and microiontophoretically applied NA (100-200 nA) was antagonized during microiontophoretic application of sotalol, a beta-adrenergic antagonist, but not affected by phentolamine, an alpha-adrenergic antagonist. When HRP at doses of 300-500 nA was applied for 5-15 min to the immediate vicinity of the STN relay or interneuron, which was electrophysiologically identified by stimulating the ipsilateral trigeminal nerve and contralateral medial lemniscus, the injection site was localized to an area 0.3 mm in diameter and HRP-reactive cells were found in the ipsilateral LC, dorsal raphe nucleus and periaqueductal gray ventral to the aqueduct. These results strongly suggest that NA released from the nerve terminals of LC cells inhibits transmission in the STN relay neuron via beta-adrenergic receptors.

Animals↗
PubMed1986

Autocrine regulation of glial proliferation and differentiation: the induction of cytodifferentiation of postmitotic normal glioblast by growth-promoting factor from astrocytoma cell.

A growth-promoting factor (GPF) from astrocytoma cells (GA-1) cultured in serum-free medium (N2) exerted on normal glioblasts proliferative and differentiation-promoting effects, which have been observed in glia maturation factor (GMF) stimulation. The serum-free conditioned media of GA-1 provoked DNA synthesis of glioblasts, and subsequently elicited a morphological differentiation characterized by the extrusion of processes as well as biochemical changes including an increased cellular level of glia fibrillary acidic protein (GFA protein), S-100 protein, and alpha-enolase. The transforming growth factor activity was also found in the media. Partially purified GPF had a molecular weight range of 7100-10,000 Mr and acidic isoelectric point (pH 4.6), and showed a susceptibility to heat treatment and denaturation at low and high pHs. The present results and the findings accumulated from our previous studies on gliotrophic growth factors provide a general concept of the growth and differentiation regulations of normal or neoplastic glial cells by growth factors through autocrine systems.

Animals↗
PubMed1986

Fat in the dural sinus.

Fat density in the dural sinus on computed tomography (CT) is described in eight cases. Of the eight cases, five had fat deposit in the torcular Herophili, and three in the superior sagittal sinus. This finding was incidentally found by CT and there was no common underlying disease in these cases. It is suggested that this finding represents normal adipose tissue in the dural sinus.

Adipose Tissue↗
PubMed1986

Direct projection of type II vestibular neurons to eye movement-related pause neurons in the cat pontine reticular formation.

Brain stem pause neurons play an important role in the regulation of rapid eye movements. However, the input sources that drive pause neurons are uncertain. In the present study, horizontal canal type II neurons in the medial vestibular nucleus were antidromically activated by electrical stimulation of the pause neuron region. Systematic microstimulation tracks within that region showed an antidromic activation pattern of low-threshold sites separated by high-threshold sites consistent with axonal branching of type II neurons in the pause neuron region. Spike-triggered averaging of single spontaneously firing type II vestibular neuronal discharges in the pause neuron region resulted in short-latency, positive field responses. These results supported the conclusion that horizontal canal type II neurons of the medial vestibular nucleus project to and inhibit pause neurons monosynaptically.

Animals↗