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Biomedical subjects

S Fujimoto

Publications and source records attributed to S Fujimoto.

At least 1,027 records · Page 57Linked to original sources
PubMed1980

Calcium localization in the sympathetic ganglion of the bullfrog and effects of caffeine.

The localization of Ca2+ in the bullfrog sympathetic ganglion was studied using electron microscopy with Oschman and Wall's technique. When the ganglion was incubated and processed in an extremely high Ca2+ solution (20 mM) for electron microscopy, electron-dense deposits (EDD) were found at or in the plasma membranes, subsurface cisterns and mitochondria of the postganglionic neurons. These EDD were proved to contain calcium by X-ray microprobe analysis. On the other hand, they were not significant in the preganglionic terminals except those in the synaptic vesicles. Addition of caffeine (10 mM) to the incubation media and fixatives caused a drastic decrease in number of EDD of the subsynaptic membranes and the subsurface cisterns. Caffeine also reduced, but less markedly, the size and number of EDD in mitochondria. Caffeine (10 mM) prolonged the afterhyperpolarization of an action potential, reduced the amplitude of the ACh (nicotinic) potential and induced slow rhythmic hyperpolarizations in a 20 mM Ca2+ solution. These effects of caffeine which were presumably the result of an increase in the intracellular free Ca2+ were discussed in relation to the morphological data.

Acetylcholine↗
PubMed1980

Locus coeruleus-induced inhibition of dorsal cochlear nucleus neurons in comparison with lateral vestibular nucleus neurons.

The effects of conditioning stimulation of the locus coeruleus (LC) on the neuron activity of dorsal cochlear nucleus (DCN), which is rich in noradrenergic nerve terminals, were compared with those on the lateral vestibular nucleus (LVN), devoid of such terminals, to determine whether or not noradrenaline is responsible for the LC-induced inhibition. The conditioning stimuli applied to the LC had no effect on either the field potential or the spike generation of mono- and polysynaptic neurons in the LVN elicited by VIIIth cranial nerve stimulation. In contrast, the spike firing of the DCN neurons with VIIIth cranial nerve stimulation was significantly inhibited by LC conditioning stimulation. The inhibition of spike generation was mainly observed in the DCN neurons which fired spikes with a longer latency. The inhibition of DCN neurons by LC conditioning stimulation did not occur in the cats pretreated with reserpine; however, a rapid recovery of the inhibition was produced by intraventricular application of noradrenaline. These results are in good agreement with the histochemical findings and support our previous conclusion that noradrenaline acts as an inhibitory transmitter or modulator on the nuclei where noradrenergic nerve terminals derived from the LC are located. In addition, the vestibular input in the primary relay nucleus is apparently not regulated by noradrenaline originating in the LC.

Animals↗
PubMed1980

Intensified cancer themotherapy by induction of hepatic drug-metabolizing enzymes as a trial for the treatment for stomach cancer.

Studies of an intensified chemotherapy of FT-207, combined with MMC, have been under way since April 1977 in the First Department of Surgery of Chiba University Hospital and five closely related hospitals. These studies were performed on 114 patients with curative stomach cancer. The 114 patients received intravenously 0.4 mg/kg and 0.2 mg/kg of MMC on the operation day and the next day, respectively, and then intravenously 800 mg of FT-207 daily from the 10th postoperative day until discharge, followed by oral administration of FT-207, 600 mg, for more than 1 year after discharge. The 114 patients were divided into two groups. Half of the patients received 100 mg of phenobarbital and 30 mg/kg of glutathione for the purpose of induction of hepatic drug-metabolizing enzymes (induction group). Significantly higher levels of serum 5-FU released from FT-207 were observed in the patients of the induction group when compared to those of the control group. However, there was no statistically significant difference in survivals at both 12 and 24 months after operation between both groups.

Drug Therapy, Combination↗
PubMed1980

Clinical studies on the correlation between immunologic status and total gastrectomy combined with splenectomy.

The influence of splenectomy on the immunologic status of stomach cancer patients was studied. Eight gastric cancer patients having undergone total gastrectomy combined with splenectomy were evaluated immunologically. Peripheral lymphocyte counts were depressed and continued to be so in splenectomized patients. PHA-induced lymphocyte blastogenesis decreased rapidly after total gastrectomy with splenectomy and thereafter increased gradually. PHA skin test seemed to take almost the same time course. These recoveries to the normal range were observed 4 weeks after operation. In 10 other patients who had undergone total gastrectomy with splenectomy for gastric cancer and had been recurrence-free for more than 6 months, peripheral lymphocyte and T lymphocyte counts significantly increased compared with 7 cases having undergone total gastrectomy only, though no difference was seen in both PHA skin test and PHA-induced lymphocyte blastogenesis between the 2 groups.

Adult↗
PubMed1980

G-cell population and serum gastrin response to cimetidine-OXO test meal in relation to histopathological alterations in resected stomachs from patients with peptic ulcer disease.

The relationship between histopathological alterations and G-cell population in the stomach was studied in l4 resected stomachs from patients with chronic peptic ulcer disease (6 with duodenal ulcer and 8 with gastric ulcer). G-cells were identified by indirect immunoperoxidase method. When atrophy was graded three steps (0, 1, 2), the average grade of DU and GU was 0.23 and 0.89, respectively. There was a significant correlation (r=0.871, p less than 0.005) between atropic grade and G-cell population in each stomach. The mean occupation rate with intestinal metaplasia was 0.9% in DU and 35.8% in GU. There was no correlation between total pyloric area and G-cell population, however residual pyloric area excluding intestinal metaplasia correlated significantly with G-cell population (r=0.557, p less than 0.05). There was a significant difference in the mean G-cell population which were 26.5 millions in DU and 8.9 millions in GU. The mean integrated gastrin response to Cimetidine-OXO test meal were 559+/-236 pg/ml in DU and 216+/-124 pg/ml in GU, and there was significant correlation (r=0.889, p less than 0.005) between G-cell population and integrated gastrin response. The average age of both groups, however, was 27.7 in DU and 52.8 in GU, so that these differences of G-cell population and functional G-cell mass in both groups might originate in the histopathological alterations accompanying with the aging.

Adolescent↗
PubMed1980

The effect of prostaglandin E2 microinjected into the rat hypothalamus on urinary excretion of water and sodium.

1 Effects of prostaglandin E2 (PGE2) microinjected into the supraoptic (SON) and the ventromedial nuclei of the hypothalamus (VMH) on urine outflow were studied in rats anaesthetized with ethanol. 2 PGE2 injected into the SON caused antidiuresis and increased the excretion rate of Na+. These effects of PGE2 were prevented by pretreatment with phentolamine but not propranolol, suggesting that they are mediated by alpha-adrenoceptors in the SON. 3 PGE2 injected into the VMH caused diuresis and increased the excretion rate of Na+. These effects were prevented by pretreatment with propranolol but not phentolamine, suggesting that they are mediated through beta-adrenoceptors in the VMH.

Animals↗
PubMed1980

[The recent status of vibration hazards among workers at the state forests in Hokkaido (author's transl)].

In order to make clear the recent status of vibration hazards among workers belonging to the national forestry bureau in northern Hokkaido, a special health examination was carried out on 417 chain saw operators and 443 bush cutter operators. The results obtained are as follows: 1. Seven point seven percent of chain saw operators and 5.6% of bush cutter operators were diagnosed as suffering from vibration hazards. Distribution of the cases in chain saw operators was 50% in grade I, 31.2% in grade II and 18.8% in grade III, while in bush cutter operators it was 20% in grade I, 60.0% in grade II and 20.0% in grade III. 2. Six new patients were found in this special health examination. 3. Twenty-two of 76 authorized patients, who had been treated with periodical therapy and prohibited from the operation of vibratory tools until this special health examination, were diagnosed as having recovered their health because of the existance of no symptoms concerning vibration hazards. 4. Pains on pressure of the muscles were complained of at the upper arm, forearm, chest and at the back in 12.4% of chain saw and bush cutter operators. Deformities of the elbow, hand and finger joints were recognized in 12.6% of the workers, and ulnar nerve paralysis was recognized in 1.0% of them. 5. Occupational hearing loss and lumbago were diagnosed in 20.2% and 14.7% of the chain saw and bush cutter workers, respectively.

Adult↗