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T Noda

Publications and source records attributed to T Noda.

At least 433 records · Page 24Linked to original sources
PubMed1984

Nigral inputs to the pedunculopontine region: intracellular analysis.

Intracellular recordings were made from neurons of the pedunculo-pontine region (PPR), the midbrain-pontine tegmentum around the brachium conjunctivum, in pentobarbital-anesthetized cats. Stimulation of the substantia nigra (SN) induced inhibitory postsynaptic potentials (IPSPs) in PPR neurons at a short latency (mean 2.17 ms, S.D. 0.66, n = 34) with a considerably long duration (mean 65.3 ms, S.D. 22.6). These neurons were distributed not only in the pedunculopontine tegmental nucleus (27 cells), but also in the cuneiform nucleus (5 cells) and the parabrachial nucleus (2 cells). Out of 34 cells, only two cells showed convergent synaptic inputs from SN and the cerebellar nuclei. Thus, it is concluded that PPR neurons receive mainly the inhibitory inputs from SN, one of the outputs of basal ganglia, and are infrequently influenced by the cerebellar outflow.

Animals↗
PubMed1984

Response properties and morphological identification of neurons in the cat motor cortex.

Intracellular recordings and morphological identification of neurons using intracellular HRP staining were performed in the cat motor cortex. By thalamic ventrolateral (VL) or cerebellar nucleus stimulation, pyramidal cells in layer III, fast pyramidal tract neurons (PTNs) and stellate cells in layers II and III were activated with short latency and fast rising EPSPs, while pyramidal cells in layer II and slow PTNs showed longer latency and slow rising EPSPs. This difference may be related to activation through the deep and superficial thalamocortical projections. Although pyramidal cells in layer VI did not respond orthodromically to VL or cerebellar stimulation, some of them proved to receive the recurrent action of PTNs because of the response to stimulation of the cerebral peduncle (CP). One aspinous stellate cell in layer III was activated by CP as well as VL stimulation. This cell was supposed to be an inhibitory interneuron responsible for both recurrent and VL-evoked inhibition.

Animals↗
PubMed1984

Characterization of fructose 1,6-bisphosphatase from bakers' yeast.

Active nonphosphorylated fructose bisphosphatase (EC 3.1.3.11) was purified from bakers' yeast. After chromatography on phosphocellulose, the enzyme appeared as a homogeneous protein as deduced from polyacrylamide gel electrophoresis, gel filtration, and isoelectric focusing. A Stokes radius of 44.5 A and molecular weight of 116,000 was calculated from gel filtration. Polyacrylamide gel electrophoresis of the purified enzyme in the presence of sodium dodecyl sulfate resulted in three protein bands of Mr = 57,000, 40,000, and 31,000. Only one band of Mr = 57,000 was observed, when the single band of the enzyme obtained after polyacrylamide gel electrophoresis in the absence of sodium dodecyl sulfate was eluted and then resubmitted to electrophoresis in the presence of sodium dodecyl sulfate. Amino acid analysis indicated 1030 residues/mol of enzyme including 12 cysteine moieties. The isoelectric point of the enzyme was estimated by gel electrofocusing to be around pH 5.5. The catalytic activity showed a maximum at pH 8.0; the specific activity at the standard pH of 7.0 was 46 units/mg of protein. Fructose 1,6-bisphosphatase b, the less active phosphorylated form of the enzyme, was purified from glucose inactivated yeast. This enzyme exhibited maximal activity at pH greater than or equal to 9.5; the specific activity measured at pH 7.0 was 25 units/mg of protein. The activity ratio, with 10 mM Mg2+ relative to 2 mM Mn2+, was 4.3 and 1.8 for fructose 1,6-bisphosphatase a and fructose 1,6-bisphosphatase b, respectively. Activity of fructose 1,6-bisphosphatase a was 50% inhibited by 0.2 microM fructose 2,6-bisphosphate or 50 microM AMP. Inhibition by fructose 2,6-bisphosphate as well as by AMP decreased with a more alkaline pH in a range between pH 6.5 and 9.0. The inhibition exerted by combinations of the two metabolites at pH 7.0 was synergistic.

Adenosine Monophosphate↗
PubMed1984

Electrophysiological and morphological studies on thalamic neurons receiving entopedunculo- and cerebello-thalamic projections in the cat.

Electrophysiological studies on the entopedunculo- and cerebello-thalamic projections were performed by intracellular recordings in the thalamic VA, VL and VM nuclei of cats under sodium pentobarbital anesthesia. Identification of the thalamic neurons were performed electrophysiologically by antidromic activation on stimulation of the precruciate cortex (areas 4 and 6) and the caudate nucleus, and morphologically by intracellular staining with HRP through recording microelectrodes. One hundred and sixty-three neurons were collected in the VA, VL and VM nuclei. In 79 neurons penetrated in the medial and ventral parts of the VA and VL nuclei, stimulation of the entopeduncular nucleus induced monosynaptic IPSPs (latency of 1.1-3.5 ms, mean 2.07 ms). Sixteen neurons were identified as thalamo-cortical relay neurons and 3 were activated only orthodromically by precruciate stimulation. Seventy-eight neurons located dorsolaterally to the entopeduncular-influenced neurons received only cerebellar EPSPs. Only 6 neurons showed convergence of entopeduncular and cerebellar inputs. They were scattered around the border between the entopeduncular and cerebellar projection areas. Sixteen neurons could be stained intracellularly by HRP injection. From the pattern of dendritic arborization, two types of neurons can be distinguished: neurons whose dendrites spread radially in all directions and neurons whose dendrites extend mainly along the long axis of the soma for a long distance in the frontal plane, respectively. The former are relay cells to the cerebral cortex or the caudate nucleus (i.e. projection neurons) and the latter appear to be interneurons in the thalamus.

Animals↗
PubMed1984

Activated macrophages are responsible for the tumor-inhibitory effect in mice receiving intravenous injection of OK-432.

Mouse spleen cells, either pretreated in vitro with 100 U/ml of OK-432-induced IFN gamma for 18 h or obtained from mice 24 or 48 h after i.v. injection of OK-432(100 micrograms/mouse), were examined for their anti-tumor effect by Winn's neutralization assay against Meth-A tumor cells in BALB/c mice. Spleen cells treated in vitro or obtained in vivo 24 h after i.v. injection clearly neutralized the growth of admixed Meth-A cells. Two booster injections of 200 U of IFN gamma near the tumor site accelerated this neutralizating effect. In order to determine the effector subpopulation, inhibitory spleen cells were treated with either anti-Thy-1 monoclonal antibody plus complement, anti-asialo GM1 serum plus complement or with adherence on plastic plates followed by Sephadex G-10 column treatment. The effector cell activity in Winn assay was lost only after the removal of macrophages through plastic plate adherence and Sephadex G-10 column treatment, but not after anti-Thy-1 or anti-asialo GM1 treatment, with either in vitro- or in vivo-treated spleen-cell populations. The growth of Meth-A cells was inhibited not only by these activated macrophages in Winn's assay, but also by adoptive transfer of OK-432-induced cytotoxic macrophages intralesionally 4 days after the implantation of 1 X 10(6) Meth-A cells. Our evidence suggests that the systemic action of OK-432 can be explained by the effect of induced IFNgamma, through the activation of macrophages.

Animals↗
PubMed1984

Angioarchitectural study of esophageal varices. With special reference to variceal rupture.

Pathomorphological and angioarchitectural characteristics of esophageal varices, mainly of ruptured varices, were studied in autopsy cases. Contrast medium was injected into the esophageal vein in 25 among 75 cases with varices, and in 4 cases without varices as a control. Out of the 75 cases with varices, rupture was confirmed in 8 cases. Ruptured points were recognized at the oral end of the longitudinal veins (these veins were called "sudare-like veins" in this study) in the lamina propria at the lower end of the esophagus in all of the 8 cases. This ruptured area was called the "critical area". By morphometric examination, dilatation of these sudare-like veins was the most obvious in severe varices, and these veins were observed to penetrate the muscularis mucosae to connect to the submucosal veins at the critical area. This area seemed to be of the greatest significance in the pathogenesis of spontaneous variceal rupture.

Endoscopy↗
PubMed1984

Studies of circulating parathyroid hormone in man by a homologous amino-terminal specific radioimmunoassay.

A homologous radioimmunoassay specific for amino-terminal portion of human parathyroid hormone(PTH) was developed in order to study the clearance of biologically active species of the hormone in the circulation in man. Characterization of the assay system with synthetic analogues of human PTH (1-34) indicated that the carboxyl-terminal region of human PTH(1-34) is an important recognition site. Plasma amino-terminal PTH levels were less than 0.3 ng/ml in all of 35 normal subjects. The levels were elevated above 0.3 ng/ml in 15 of 24 patients with primary hyperparathyroidism. In 5 patients in whom the levels were determined before and after parathyroidectomy, the elevated levels were all normalized within 60 minutes after the removal of adenomata. The disappearance of exogenous human PTH(1-34) was studied after intravenous administration in 17 patients with hypoparathyroidism. A graphical analysis of the data disclosed two major components of the disappearance curve with estimated half-disappearance time of 3 and 28 minutes respectively, suggesting that multiple mechanisms are involved in the clearance of the peptide from the circulation. These results demonstrate usefulness of homologous radioimmunoassay for human PTH(1-34) in diagnosis and management of hyperparathyroidism, as well as in studying the clearance of amino-terminal portion of PTH which is known to represent biological activity.

Humans↗
PubMed1984

Studies on macrocyclic lactone antibiotics. VII. Structure of a phytotoxin "rhizoxin" produced by Rhizopus chinensis.

A new 16-membered macrolide designated as rhizoxin was isolated as a toxin produced by Rhizopus chinensis, the causal agent of rice seedling blight . The skeletal structure was determined by detailed NMR spectroscopic investigation of this compound and of its derivatives. Rhizoxin induced at a concentration of 10 ng/ml abnormal swelling of rice seedling roots, which is one of the characteristic symptoms of this disease. This compound also exhibited potent antifungal activity but little effect against bacteria.

Anthraquinones↗
PubMed1984

[Effect of elcatonin on experimental osteoporosis induced by ovariectomy and low calcium diet in beagles].

Effect of elcatonin, a synthesized analogue of eel calcitonin, on experimental osteoporosis in beagles induced by ovariectomy and a low calcium diet was studied. Twelve female beagles, 15-18 months old, were divided equally into 3 groups. The first group of beagles were ovariectomized and then fed a low calcium diet, Ca: 0.08%, (ovariectomy plus low Ca diet group); the second group was subjected to the same procedure and diet plus daily injection of elcatonin, 1.0 u/kg, i.m., (elcatonin group); and the third group was fed a standard diet, Ca: 1.36%, (control group) for 6 months. The undecalcified bone sections from the iliac crest were analyzed using histomorphometric methods following in vivo double labeling with Calcein. In the ovariectomy plus low Ca diet group, there were a decrease in trabecular bone volume and an increase in both resorption and formation surface of the trabeculae compared with the control group. These changes of trabecular bone volume and resorption surface were significantly prevented by daily injection of elcatonin. The increase of formation surface of trabeculae and mineral appositional rate was noted in the elcatonin group in comparison with the ovariectomy plus low Ca diet group. These results suggested that elcatonin could prevent bone loss caused by deficiency of sex hormone and dietary calcium.

Alkaline Phosphatase↗