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Biomedical subjects

Y Oda

Publications and source records attributed to Y Oda.

At least 667 records · Page 37Linked to original sources
PubMed1982

Formation of functional synapses in the adult cat red nucleus from the cerebrum following cross-innervation of forelimb flexor and extensor nerves. II. Analysis of newly appeared synaptic potentials.

The effects of cross-innervation of peripheral flexor and extensor nerves on the time course and properties of red nucleus (RN) neurons were studied in adult cats. The time course of corticorubral unitary EPSPs was examined. In operated cats, RN neurons innervating upper spinal segments (C-cells) manifested corticorubral unitary EPSPs with shorter time-to-peak and larger amplitude than in normal cats. The mean amplitude of these EPSPs was 0.41 +/- 0.11 mV; the mean time-to-peak was 1.14 +/- 0.51 ms (n = 18). These values differ from normal cats (0.33 +/- 0.09 mV, and 2.68 +/- 0.61 ms, n = 22). RN neuron membrane properties were examined in cross-innervated cats. The main time constant was 5.2 +/- 0.7 ms (n = 10), the shorter equalizing time constant, 0.69 +/- 0.19 ms (n = 10), the input resistance, 2.5 +/- 0.8 M omega. These values were not significantly different from those of normal cats. The electrotonic length was 1.2 (n = 10), somewhat larger than in normal cats. The number of converging interpositorubral synapses, estimated in eight cells from cross-innervated cats, ranged from 37 to 57. This was not significantly different from normal cats, and indicated that there is no large-scale degeneration of interpositorubral synapses after cross-innervation. These results suggest that sprouting and formation of functional synapses occur after cross-innervation of peripheral flexor and extensor nerves.

Animals↗
PubMed1982

Efficacy of a blood substitute (Fluosol-DA, 20%) on cerebral ischemia.

Fluosol-DA, 20%, was intravenously infused in 28 patients suffering from cerebrovascular disease, and was found to be effective in 60% of the cases with vasospasm and in 80% of the cases with stenosis and/or occlusion of the artery. Administration of the solution increases r-CBF by 10.1 to 37.9% when measured by either intra-arterial injection or inhalation of 133Xe. However, an increase of arterial oxygen tension appears to have little effect on r-CBF after administration of the solution. The increase of r-CBF caused by Fluosol-DA, 20%, may be due not only to the lowering viscosity of the mixed blood but also to its direct effect on dilating cerebral vessels.

Adult↗
PubMed1982

Leukemic optic neuropathy.

7 cases of leukemic ophthalmopathy were clinicopathologically studies. The present findings were as follows: (1) ocular manifestations were exactly parallel with the involvement of the central nervous system, (2) visual disturbance seemed to be caused mainly by neoplastic infiltration into the parenchyma of the optic nerve, compression of nerve fibers due to neoplastic invasion in the septal tissues, and vascular disturbance, and (3) the mechanism of papilledema or disc swelling might be chiefly attributed to neoplastic infiltration into the optic nerve and/or the central nervous system.

Adolescent↗
PubMed1982

[Changes of blood pressure and regional blood flow in SART rats and drug actions on these changes (author's transl)].

In order to investigate the function of the circulatory system in SART rats, systolic blood pressure and regional arterial blood flow were examined. It was found in SART stressed rats that the blood pressure was about 10 mmHg lower than that of the non-stressed group on the 6th day of stressing and after stressing, and such low blood pressure was maintained for several days. SART rats showed a decrease in the average blood flow value in the common carotid artery, increases in the average and instantaneous maximum blood flow values in the superior mesenteric artery, and the instantaneous maximum blood flow value in the abdominal aorta had a tendency to increase, though little changes were observed in the renal and the femoral arteries. It was suggested by flow contours that there was hardening in the vessel walls of the common carotid artery and the abdominal aorta, and softening in the superior mesenteric artery. SART stress-induced hypotension was further decreased by a single dose of guanethidine, clonidine, or hydralazine, but not by neurotropin. Continuous preadministration of neurotropin prevented the SART stress-induced hypotension and changes in blood flow. From the above mentioned results, the sympathetic nerve may be thought to be decreased in tension, or be depressed, in the circulatory system of SART rats.

Animals↗
PubMed1982

[Detection and clinical significance of immune complexes in the sera of brain tumor patients].

Levels of circulating immune complexes (IC) in the sera of 87 patients with brain tumor were measured by Raji cell radioimmunoassay and Clq binding assay. The control samples were obtained from 40 healthy blood donors and 40 cerebrovascular patients. The patients with glial tumor had a high incidence of elevated level of IC than patients with non-glial benign tumor, elevated level of IC than patients with non-glial benign tumor, cerebrovascular disease and normal controls. There was a significant association between these Clq binding activity and Raji cell binding activity in the sera of glial tumor patients. As regards the sensitivity, high IC levels are more frequent among Raji cell assay than Clq binding assay. The level of IC was found to be higher in patients with recurrent glial tumor than in those with primary tumors. However, the level of IC in the sera from patients with glial tumor did not always decrease during remission after successful treatment. Our data indicate that the measurement of IC may prove useful in the management of patients with brain tumor, in particular, to detect recurrence or progression of tumor growth.

Antigen-Antibody Complex↗
PubMed1982

[Clinical management of acute lymphocytic leukemia in adults. 1. Treatment of acute lymphocytic leukemia with VP (vincristine, prednisolone)--DVMP (daunorubicin, vincristine 6-mercaptopurine, prednisolone) regimen].

Eighteen patients with acute lymphocytic leukemia (ALL) were treated with VP (vincristine, prednisolone) followed by DVMP (daunorubicin + vincristine + 6-mercaptopurine + prednisolone) regimen (VP-DVMP regimen). Patients were all previously untreated. Complete remission (CR) was obtained in 11 of 18 patients (61.1%,) by VP alone and 4 patients, by VP-DVMP. The time required for CR varied from 14 to 60 days with a median of 28 days. The duration of CR and survivals in responders were from 1.2 to 42.3 + months with a median of 24.0 months. The hematological toxicities in VP-DVMP regimen were lower than those in NVP (neocarzinostatin + vincristine + prednisolone) and NVMP (neocarzinostatin + vincristine + 6-mercaptopurine + prednisolone) regimens.

Adolescent↗
PubMed1982

[Comparative evaluation of a combination of daunorubicin and cytosine arabinoside and that of aclarubicin and cytosine arabinoside in remission induction in acute non-lymphocytic leukemia].

A comparative trial of a combination of daunorubicin and cytosine arabinoside (Regimen A) and a combination of aclarubicin and cytosine arabinoside (Regimen B) was performed. Sixteen patients with acute non-lymphocytic leukemia, previously untreated, were entered into this study. Five of 8 patients (62.5%) obtained a complete remission (CR) in Regimen A and B, respectively. The days required for achieving a CR varied from 37 to 46 days in Regimen A and from 22 to 56 days in Regimen B. The total doses of daunorubicin and cytosine arabinoside were from 100 to 240 mg and from 640 to 1,120 mg in Regimen A, respectively. Those of aclarubicin were from 180 to 300 mg and from 660 to 1,000 mg in cytosine arabinoside in Regimen B. In a comparative study on hematological changes, toxic effects on peripheral white blood cell, platelet and nucleated cell counts in bone marrow tended to appear later in Regimen B compared to those in Regimen A. Side effects on digestive system such as nausea and vomiting and vascular pain were more frequently recognized in patients treated with Regimen B, although they were managed by symptomatic treatment. The results indicated the usefullness of aclarubicin in combination chemotherapy for the treatment of acute non-lymphocytic leukemia.

Aclarubicin↗
PubMed1982

[Nocardia brain abscess: a case report (author's transl)].

A 42 years old woman was noticed to have an abnormal shadow in the left lower field of lung at the time of periodical chest radiographic examination in July 1979. She didn't show any signs or symptoms of inflammation such as fever, increased rate of blood sedimentation, leukocytosis and so on by that time. Four weeks prior to admission she started to complain of mild but continuous headache and then developed anorexia, dysarthria and weakness in the right half of the face. She was admitted to the Kyoto University Hospital on September 14, 1979. On admission, slight bilateral papilledema, right hemiparesis and total dysphasia were present. She was afebrile and no abnormal finding in serological examination was shown. A heterogenously enhanced mass was demonstrated by CT scan in the left posterior frontal lobe, which was surrounded by severe cerebral edema. A provisional diagnosis of metastatic tumor from the lung was made. At the time of craniotomy, an abscess cavity was found and aspirated. Then the radical extracapsular ablation and external decompression was carried out. Histologically many Nocardia species were identified in the abscess cavity. The patient was treated by administration of a mixture of trimethoprine and sulfamethixazole (Bakter), and minocycline. Subsequently the developed Corynebacterial epidural empyema which was successfully evacuated two months after the first operation. She had been placed on Baktar for ten months since the second operation. She presented no sign of recurrence in six months after the cessation of drugs.

Adult↗
PubMed1982

[Treatment of brain tumors with anticancer pellet--experimental and clinical study (author's transl)].

Eighty three patients suffering from brain tumors have been treated by anticancer pellets containing 5-FU, urokinase, mitomycin and BUdR in dimethylsiloxan (Silastic) for three years. Constant and prolonged release of the chemicals from the anticancer pellet had already been proved in vitro. The amount of daily release were 1-3/1,000 of original volume. Tissue concentration of 5-FU was measured by bioassay system using staphylococcus 209 P strain with plate dilution method. In spite of the rapid disappearance of serum 5-FU, the local high accumulation of 5-FU was demonstrated in vivo. In rat neurogenic tumor, 1.104 microgram/g was detected on 60 days after the application of anticancer pellet containing 500 mg of 5-FU. The growth of tumor was also suppressed. The clinical study consists of 83 patients, 30 of glioblastoma, 19 of metastatic brain tumor, 13 of astrocytoma, 7 of oligodendroglioma, 4 of ependymoblastoma, 4 of malignant lymphoma and 6 of others. The median survival time of gliblastoma was prolonged to 71.5 weeks by the implantation of anticancer pellet from 40 weeks of control group. However, the median survival time of astrocytoma and metastatic brain tumor were 24 and 6 months, respectively, which have no significant difference from control groups. In the patients of metastatic brain tumor, the regrowth of metastatic foci in the brain was completely suppressed. However, most of them were succumbed from the original tumors. The concentration of 5-FU in several human tissue was measured in ten patients with different time intervals after the implantation of the anticancer pellet. Although they have different histologic patterns, the concentrations of 5-FU in human brain tumors were ranged from 0.05 to 0.67 microgram/g by 14 months after the implantation of the anticancer pellet. The adjacent cystic fluids also contain from 0.62 to 4.9 microgram/ml of 5-FU for two years. These results mean that they are keeping higher level of 5-FU than the tumoricidal level of 5-FU (0.056 microgram/g) for more than two years. On the other hand, no respective accumulation was demonstrated in other tissues. None of the patients showed any adverse reactions except a continuous slight fever up to 38 degrees C.

Adult↗
PubMed1982

[Intracerebral picibanil injection in the rat neurogenic tumor--its histopathological changes].

Penicillin-free-Picibanil was injected into the brain of Wistar/Fibiger strain rat to investigate the histological changes. Its effect on the growth of rat schwannoma inoculated in the brain was also examined histologically. Picibanil caused the most prominent but focal lymphoreticular cell reaction around the injected site in the brain 24 to 48 hours after injection. The cells infiltrating from the blood vessels were neutrophils, monocytes, lymphocyte-like cells, histiocyte-like cells and unidentified cells. This lympho-reticular cell reaction gradually subsided in the next 4 to 5 days. Neutrophils and monocytes (macrophages)stayed till the later phase. Two weeks later, the lesion was minimal with only mild glial changes. Picibanil was however, considered to exert at the site of injection neurotoxic and glia-toxic activity at a concentration of 0.1 KE/10 microliters. The rat schwannoma (T1) cells, when inoculated without any treatment, showed vivid growth in the brain and no lympho-reticular cell reaction was observed. When the T1 tumor cells, suspended in the Picibanil solution, were inoculated into the brain, no lymph-reticular cell reaction was observed 7 and 14 days after inoculation. However, when the rat was pretreated with Picibanil into the brain 7 days before inoculation, only a mild lymphoreticular cell reaction was observed around the T1 cells till 7 days after inoculation. Accordingly, Picibanil was considered to induce nonspecific immunological in the rat brain even around the glioma.

Animals↗
PubMed1982

[Clinical evaluation of artificial blood substitute (fluosol-DA 20%) in patients of cerebral ischemia].

The efficacy of perfluorochemicals (Fluosol-DA 20%) as an erythrocyte substitute and the changes of regional cerebral blood flow (r-CBF) following the administration of Fluosol-DA were studied. Seventy-three patients suffering from cerebral ischemic diseases were treated by 10 m/kg of Fluosol-DA. Intravenous infusions were performed 126 times. Clinical efficacy could be estimated by neurological signs, r-CBF and EEG findings in 53 patients who were in acute or subacute stage of diseases. These patients were classified into three groups; 1) Vasospasm group consists of 21 patients and 43 times of infusion, 2) Stenosis or occlusion group consists of 21 patients and 29 times of infusion, and 3) Others. Improvement occurred in 65.1% and 65.5% of vasospasm, and occlusion group, respectively. No aggravated case was noted. One out of 126 infusions showed an exanthema. Changes of r-CBF was measured in 20 cases on 32 hemispheres by either inhalation or intra-arterial infection of 133Xenon. r-CBF was increased 25.0% after the administration of Fluosol-DA when measured by intraarterial injection of 133Xenon. The increase of 16.9% in r-CBF was found in 11 cases by the inhalation method. These values were well correlated with that of animal study using monkeys measured by hydrogen clearance method. From the comparison of the effect of Fluosol-DA and Hespander on r-CBF, the mechanism of increased r-CBF by Fluosol-DA 20%, which contains 2.9% of hydroxyethyl-starch, was considered to be not solely due to the lowering of blood viscosities but also due to the dilating effect on cerebral vessels.

Adolescent↗
PubMed1981

Simple and complex spike activities of Purkinje cells during locomotion in the cerebellar vermal zones of decerebrate cats.

In walking cats decerebrated at the premammillary level, single neurone activity of Purkinje cells (P-cells) with long corticofugal axons was recorded in the cerebellar vermis. The P-cells (N = 145) were identified as they showed spontaneous simple and complex spikes and also antidromic activation from Deiters' nucleus. These P-cells were classified into 6 groups according to the receptive fields of the climbing fibre responses (CFRs) which were evoked by electrical stimulation in each limb at the radial and sciatic nerve bundles. One group designated as forelimb units received the CFRs from both forelimbs and from neither hindlimb. According to previous studies, this group of P-cells is thought to make inhibitory connections with Deiters neurones projecting to the ipsilateral cervicothoracic spinal cord. For the forelimb units, two types of discharge patterns for simple spikes were found in relation to limb movements during locomotion. Type I cells showed one peak in their firing rate in the late swing (E1) or early stance (E2) phase of the ipsilateral forelimb. Type II cells showed two peaks and two valleys during one step cycle: one peak was in the E1 phase, the other in the late stance (E3) or early swing (F) phase; each of the two valleys followed the peak. Complex spikes of the forelimb units occurred more frequently in the E1 phase than during the other phases. The increased activity of simple and complex spikes of the forelimb units in the E2 phase is suggested to have a functional significance in preparing the appropriate floor reaction forces that appear upon touchdown on the ipsilateral forelimb.

Animals↗