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J Tanaka

Publications and source records attributed to J Tanaka.

At least 757 records · Page 42Linked to original sources
PubMed1985

Inputs from the A1 noradrenergic region to hypothalamic paraventricular neurons in the rat.

Electrical stimulation of the rat A1 noradrenergic region produced excitation (77%) of the activity of putative vasopressin (VP)-secreting neurons in the paraventricular nucleus (PVN) and produced excitation (4%), inhibition (26%) and excitation-inhibition (11%) of the activity of PVN neurons that were not antidromically identified by neurohypophysial stimulation. The excitatory response of putative VP-secreting neurons was blocked by microiontophoretically applied phentolamine, an alpha-adrenoceptor antagonist, but not by timolol, a beta-adrenoceptor antagonist. The inhibitory response of unidentified PVN neurons, on the other hand, was blocked by timolol, but not by phentolamine.

Adrenergic Fibers↗
PubMed1985

Changes in coenzyme Q level in mitochondria of cirrhotic rat liver.

In the cirrhotic rat liver induced by carbon tetrachloride and phenobarbitone, the concentrations of mitochondrial Coenzyme Q were measured in comparison with other respiratory components. The concentration of cytochrome a(+a3) and Coenzyme Q significantly increased in the cirrhotic liver, without any changes in the ratio of Coenzyme Q to cytochrome a(+a3). It is suggested that such increase of Coenzyme Q plays an important role as one of the adaptive responses to compensate for the prolonged metabolic overload on the mitochondrial respiratory assembly. Also, from the findings that the concentrations of cytochrome a(+a3) in the mitochondria of cirrhotic liver increase concomitant with the severity of cirrhosis, it is suggested that the rise of Coenzyme Q levels may be one of the indicators for the decreased functional reserve capacity in liver cirrhosis.

Animals↗
PubMed1985

Abortive infection with human cytomegalovirus induces an alteration of growth pattern: morphological changes with cytocidal effect in rabbit kidney epithelial cells. Brief report.

Rabbit kidney epithelial cells (RK13) exhibited a cytopathic effect (CPE) characterized by cell rounding after infection with human cytomegalovirus (HCMV). Although HCMV-specific immediate early and early antigens were detected by indirect immunofluorescence techniques, neither late antigens nor infectious progeny virus could be observed in virus-infected RK13 cells. HCMV-infected RK13 cells showed a prolonged doubling time and a decreased saturation density in cell growth compared to uninfected control cells. Moreover, colony forming ability (CFA) of virus-infected cells decreased by approximately 70 per cent compared to that of uninfected cells during the first 24 hours after infection. These results indicate that an abortive infection of RK13 cells with HCMV induces an alteration of growth pattern including morphological changes with cytocidal effect.

Animals↗
PubMed1985

Response of phasically firing paraventricular neurons to A1 noradrenergic region stimulation and its attenuation by adrenoceptor antagonists.

In urethane-anesthetized rats electrical stimulation of the A1 noradrenergic region in the ventrolateral medulla produced excitatory (27%), excitatory-inhibitory (24%), or inhibitory (34%) responses of spontaneous activity of phasically firing units in the paraventricular nucleus (PVN) of the hypothalamus. The latency of excitatory responses was significantly shorter in those followed by inhibition, suggesting the existence of two distinct excitatory pathways. The latency of inhibitory responses, however, was not different between primary and postexcitatory inhibitory responses. Effects of alpha- and beta-adrenoceptor antagonists on responses of phasically firing PVN units to stimulation of the A1 region were tested. The excitatory responses that were not followed by inhibition were significantly attenuated by intraperitoneal phenoxybenzamine, whereas the other responses were not affected. Both primary and postexcitatory inhibitory responses were significantly attenuated by intravenous propranolol, whereas neither type of excitatory response was affected. These results suggest that the medullary (A1 region) inputs to phasically firing PVN units are mediated by alpha-adrenergic (excitatory), beta-adrenergic (inhibitory), and nonaminergic (excitatory) pathways.

Adrenergic alpha-Antagonists↗
PubMed1985

The histidine permease gene (HIP1) of Saccharomyces cerevisiae.

The histidine-specific permease gene (HIP1) of Saccharomyces cerevisiae has been mapped, cloned, and sequenced. The HIP1 gene maps to the right arm of chromosome VII, approx. 11 cM distal to the ADE3 gene. The gene was isolated as an 8.6-kb BamHI-Sau3A fragment by complementation of the histidine-specific permease deficiency in recipient yeast cells. We sequenced a 2.4-kb subfragment of this BamHI-Sau3A fragment containing the HIP1 gene and identified a 1596-bp open reading frame (ORF). We confirmed the assignment of the 1596-bp ORF as the HIP1 coding sequence by sequencing a hip1 nonsense mutation. Analysis of the amino acid (aa) sequence of the HIP1 gene reveals several hydrophobic stretches, but shows no obvious N-terminal signal peptide. We have constructed a deletion of the HIP1 gene in vitro and replaced the wild-type copy of the gene with this deletion. The hip1 deletion mutant can grow when it is supplemented with 30 mM histidine, 50 times the amount required for the growth of HIP1 cells. Revertants of this deletion mutant able to grow on a normal level of histidine arise by mutation in unlinked genes. Both these observations suggest that there are additional, low-affinity pathways for histidine uptake.

ATP-Binding Cassette Transporters↗
PubMed1985

Neoadjuvant chemotherapy in maxillary sinus carcinoma with cisplatinum and peplomycin intraarterial infusion.

The purpose of this paper is to present our preliminary assessment of a new multimodal treatment including neoadjuvant chemotherapy with cisplatinum and peplomycin for maxillary sinus carcinoma. Fifteen patients with squamous cell carcinoma of the maxillary sinus carcinoma seen at Keio University Hospital, with Stage III and IV disease, were enrolled in this trial between January 1982 and January 1985. Regimen of chemotherapy was as follows: day 1, 50 mg/m2 of cisplatinum, intraarterial infusion over 2 hr, days 2-6, peplomycin at a dose of 5 mg/day, intraarterial infusion over 5 hr. Routinely, radiotherapy of 40 Gy by Linac was given to the primary site, concomitantly combined with 5-fluorouracil intraarterial injections only during the first 10 days, 2 weeks after the end of initial chemotherapy. Additional treatment was performed according to the extent of residual tumor. Response to initial chemotherapy revealed that complete response was achieved in 7 and partial response in 6 out of 15 patients with a response rate of 87%. Nine patients required no surgical intervention while 6 underwent a surgical resection. Median follow-up in this group of patients is 20 months. Thirty-month survival rate calculated by Kaplan-Meier's method was 83%. Chemotherapy toxicity was mild in most cases. This pilot study does not provide conclusive survival information, but the results obtained are encouraging.

Aged↗
PubMed1985

Clinical trials on UFT in the treatment of head and neck cancer.

A new anticancer agent, UFT which is a mixture of 1-(2-tetrahydrofuryl)-5-fluorouracil and uracil in a molar ratio of 1:4 was administered orally at a dose of 600 mg/day every day. Forty-three patients were evaluable. Eight patients achieved a complete response and eight achieved a partial response with an overall response rate of 37.2%. In terms of response by histology, a response rate was 32.4% (11/34) in cases of squamous cell carcinoma and 75% (3/4) in cases of adenocarcinoma. A response rate by primary site was 57.1% in the nose and paranasal sinuses, 50.0% in the oropharynx and 30.0% in the oral cavity. A response rate was 36.1% in patients with prior treatment and 42.9% in patients with no prior treatment, but there was no statistical significance. Eight of 43 patients developed toxic effects. Most of them were mild such as anorexia, nausea, and stomatitis, but in one case of maxillary sinus carcinoma, severe bone marrow suppression was observed. UFT is a considerably effective and useful drug in the treatment of head and neck cancer. It is possible to increase cure rate by examining various usages of UFT.

Adult↗
PubMed1985

Developmental changes of neuron-specific enolase in human brain: an immunohistochemical study.

Developmental changes of neurons containing neuron-specific enolase (NSE) in human brain were studied in various areas of the central nervous system by immunohistochemistry with the peroxidase-antiperoxidase (PAP) method. In the brain stem, Purkinje cells, dentate nucleus, globus pallidus and thalamus, the number of NSE-positive neurons increased from an early period in gestation. However, in the pontine nucleus and putamen, it gradually increased along with decreasing cellularity later in gestation and in the infantile period. In the cerebral cortex, NSE-positive neurons developed as late as in the putamen and their cellularity increased earlier in the 5th layer than in the 3rd layer. Developmental changes of NSE-positive neurons parallel phylogenesis. The appearance of NSE-positive neurons can be a marker of neuronal maturation.

Adolescent↗
PubMed1985

Influence of microinjection of insulin into ventromedial hypothalamus on acetate metabolism in liver slices of rabbit.

Insulin was injected directly into the ventromedial hypothalamic nuclei (VMH) of rabbits, and changes in hepatic acetate metabolism were studied. The injection of 50 microU insulin into the VMH of intact rabbits decreased the rates of 14C transfer from 14C-1-acetate into glucose and cholesterol ester in liver slices. But after insulin injection into the parietal cortex of intact rabbits and into the VMH of rabbits with VMH lesions, hepatic acetate metabolism did not differ from that of the control rabbits, which received saline injection into the same brain regions. These observations support the hypothesis that the VMH are parts of an insulin-sensitive brain regulator system in the hepatic acetate metabolism.

Acetates↗
PubMed1985

Influence of lesions in the limbic-hypothalamic system on metabolic responses of pyruvate to daily repeated heat exposures in rabbits.

The effects of lesions of the limbic-hypothalamic structures on the pyruvate metabolic responses to daily repeated heat exposures in the liver of rabbits have been investigated. The experimental results were as follows: 1. The pyruvate metabolic responses to the 1st heat exposure (heat exposure on the 1st day) were altered by lesions of periventricular arcuate nucleus (ARC), ventromedial hypothalamus (VMH), stria terminalis (ST) and dorsal fornix (FX). 2. The pyruvate metabolic responses to heat exposure were completely abolished by the ten times repetition of daily heat exposures in rabbits with lesions of ARC, VMH and ST, as same as in each sham-operated group. 3. In rabbits with FX lesions, the pyruvate metabolic responses to heat exposure remained even after the ten times repetition of daily heat exposures. 4. From these results, it might be suggested that ARC, VMH, amygdala (AMYG)-ST system and dorsal hippocampus (HPC)-FX system played a certain role in the mechanisms of pyruvate metabolic responses to the 1st heat exposure, but only the HPC-FX system participated in the process of pyruvate metabolic adaptation to daily repeated heat exposures.

Animals↗
PubMed1985

Reduced citrovorum factor rescue for high-dose methotrexate therapy in childhood malignancies.

Clinical toxicities and pharmacokinetics of methotrexate (MTX), associated with reduced citrovorum factor (CF) neutralization, were studied on 279 infusions in 25 children with various malignancies. MTX, at 1000-8400 mg/m2, was infused during six to 24 hours with multiple schedules of reduced CF rescue. Plasma MTX levels ranged from 7.0 X 10(-5) to 7.0 X 10(-4) M during MTX infusion. The levels declined rapidly with a two-phase elimination pattern (t1/2 = 1.2-2.5 hours, t1/2 = 18-32 hours). The folate level in the plasma ranged from 5 X 10(-7) M to 1.4 X 10(-6) M when CF was administered every six hours or every three hours, respectively. Limited bone marrow suppression was seen in only seven percent of infusions, with moderate elevation of GOT and GPT in 20% of infusions, and stomatitis in only 2.6% of infusions, despite reduction in the total dose of CF from 225 mg to 105 mg and despite delaying CF initiation from nine hours to thirty-six hours after the start of MTX infusion.

Adolescent↗
PubMed1985

[Multidisciplinary treatment of head and neck cancer].

A new multidisciplinary treatment for head and neck cancer was shown by focusing on the maxillary and oropharyngeal carcinoma. Neo-adjuvant chemotherapy which consists of cisplatin and peplomycin was incorporated into it. In terms of maxillary carcinoma, 2 courses of chemotherapy were given with an interval of 2 weeks, followed by radiotherapy (40 Gy) combined with intraarterial chemotherapy (5-FU). When no cancer cells were detected at the completion of this therapy, adjuvant chemoimmunotherapy was given. When an apparent tumor was still revealed by CT, radical surgery was performed. When cancer cells were detected only by histological examination, additional radiotherapy up to 60 Gy was given by Linac. The results obtained were analysed in 14 cases. We also presented another type of multidisciplinary treatment in oropharyngeal carcinoma.

Aged↗
PubMed1985

[Preoperative chemotherapy for head and neck cancer].

The authors have studied preoperative chemotherapy for head and neck cancer since 1963, focusing on intra-arterial chemotherapy. The results obtained revealed that preoperative chemotherapy played an important role in the improvement of 5-year survival in maxillary sinus carcinoma and tongue carcinoma. However, functional and cosmetic damage after radical surgery has newly energed as problems to be resolved. The appearance of cisplatin has raised an important the level of effectiveness of cancer chemotherapy in recent years. Since the combination of cisplatin and bleomycin analogs revealed a remarkable synergistic effect in experimental chemotherapy, it has been used clinically as preoperative or preradiation chemotherapy for advanced Stage III and IV head and neck cancer. Under the above-mentioned circumstances, treatment for head and neck cancer has undergone various changes over the past twenty years. At present it is no exaggeration to say that the period in which dependence was placed on only surgery and/or radiation is over. The authors would like to emphasize that preoperative chemotherapy should be carried out as a part of multidisciplinary approach under a new concept of neo-adjuvant chemotherapy which includes not only preoperative chemotherapy but also preradiation chemotherapy. The role of preoperative chemotherapy, its current status and future prospects are discussed in this paper, looking back on the history of chemotherapy for head and neck cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1985

[Phase II study of UFT for head and neck cancer].

A Phase II study of UFT for head and neck cancer was conducted in 10 institutions. UFT is a mixture of Futraful and uracil. Eighty-four patients entered this trial, of which 60 were evaluable. UFT was administered orally at a daily dose of 600 mg/day. Eight patients achieved complete response and 10 achieved partial response with an over-all response rate of 30.0 %. Evaluating response according to by histology, the response rate was 30.9% for cases of squamous cell carcinoma. Complete response was observed in one case of undifferentiated carcinoma. Response rate according to primary site was 33 to 40% for the nose & paranasal sinuses, mesopharynx, hypopharynx and larynx. The response rate was 28.9% for the group of patients treated previously, and 33.3% for the group previously untreated. The mean time for 50% or more regression of the tumor was 4.3 weeks. Toxic effects appeared in 40.3% of 67 evaluable cases as anorexia, nausea, vomiting, stomatitis, diarrhea etc. In one case of maxillary carcinoma, severe bone marrow suppression was observed. We concluded that UFT therapy was markedly effective for head and neck cancer.

Adult↗