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M Takada

Publications and source records attributed to M Takada.

At least 523 records · Page 29Linked to original sources
PubMed1988

Dopaminergic nigrotectal projection in the rat.

After injecting a fluorescent tracer (Fluoro-gold) into the rat superior colliculus, retrogradely labeled neurons in the rostral, ventrolateral portions of the substantia nigra pars reticulata were also immunohistochemically labeled with tyrosine hydroxylase antisera. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) pretreatment of the medial forebrain bundle resulted in the disappearance of the nigral neurons double-labeled with the two markers. The existence of a dopaminergic nigrotectal projection susceptible to MPTP might provide a morphological substrate for abnormal saccadic eye movements in parkinsonism.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1988

Single thalamic dopaminergic neurons project to both the neocortex and spinal cord.

Cells in the rat subparafascicular thalamic nucleus (Spf) belonging to the diencephalic A11 cell group, were immunohistochemically stained with antibodies against tyrosine hydroxylase (TH) and dopamine itself. Employing a combination of retrograde fluorescent double-labeling and TH immunofluorescence techniques, we revealed the existence of dopaminergic Spf cells, giving rise to collateral projections to the neocortex and spinal cord.

Animals↗
PubMed1988

Two separate neuronal populations of the rat subthalamic nucleus project to the basal ganglia and pedunculopontine tegmental region.

Employing a retrograde fluorescent double labeling technique, we compared the localization of subthalamic nucleus (STN) cells projecting to the striatum and nucleus tegmenti pedunculopontinus pars compacta (TPC), with that of STN cells sending axon collaterals to both the globus pallidus and substantia nigra in the rat. The STN-striatal projections were mostly the third branches of massive STN-pallidal and STN-nigral collateral projection neurons, whereas only very rarely did the STN-TPC projections contribute to these collateral projections. The TPC projecting STN cells, giving rise to an independent output of the nucleus, were located mainly in its thin lateral strip region. The STN may integrate the somatic motor information from various cortical/subcortical brain areas (including the motor cortex, striatum, globus pallidus, thalamus and TPC), and disperse it predominantly to the pallidal complex, substantia nigra and striatum by way of axon collaterals, and to a lesser degree to the TPC through separate fibers. Thus, the STN might be in a strategic position to exert a prominent control over the basal ganglia-related somatic motor functions.

Amidines↗
PubMed1988

Effect of prolactin on transcutaneous Na transport in the Japanese newt, Cynops pyrrhogaster.

The effect of ovine prolactin (PRL) on the electric parameters related to active Na transport across the skin was investigated in the Japanese newt, Cynops pyrrhogaster. Spring newts living in a pond or stream for breeding and autumn newts migrating from water to land for hibernation were collected and used for the experiments. Autumn newt skin was found to have a higher transepithelial potential difference (TEP) and higher resistances to the active Na current (RNa) and to the shunt pathway (RS) than spring newt skin. Injection of PRL, 20 micrograms/g body wt, into autumn newts every other day for 2 weeks induced an increase in RNa, resulting in decreases in TEP and the short-circuit current (SCC), but barely changed the skin resistance (RM), the electromotive force of the active Na current (ENa), or RS. On the other hand, such injections of PRL into spring newts induced decreases in TEP and SCC, but had no effect on RM, ENa, RNa, or RS. Autumn newts appear to be more sensitive to PRL than spring newts. Insofar as autumn newts are concerned, it is concluded that the effect of PRL is probably due to blockade of the Na channel rather than inhibition of Na pump activity.

Animals↗
PubMed1988

Collateral projection from the substantia nigra to the striatum and superior colliculus in the rat.

Our retrograde fluorescent double labeling study demonstrated the existence of divergent collateral projections from the substantia nigra to the striatum and superior colliculus in the rat. These bifurcating projection neurons were located predominantly in the ventrolateral portions of the substantia nigra pars reticulata at its rostral level, where they formed a narrow band along the boundary between the substantia nigra and cerebral peduncle. Such specific projection cells were also seen in the substantia nigra pars lateralis. However, nigral neurons did not give off axonal branches to the striatum and ventromedial thalamic nucleus. The new nigral cell population proposed here might constitute a neuroanatomical substrate for abnormal saccadic eye movements clinically manifested by many parkinsonian patients.

Animals↗
PubMed1988

A case of disseminated trichosporonosis: a case report and immunohistochemical identification of fungal elements.

Trichosporon beigelii was isolated from blood cultures of a 69-year-old Japanese male who had been treated for chronic myeloid leukaemia with cytotoxic agents and broad spectrum antibiotics. He died of sepsis 4 days after a positive blood culture was obtained. A postmortem examination revealed abundant budding yeasts and hyphae in sections of lung, liver, bone marrow and other organs. All the fungal elements in the sections were identified as Trichosporon species by their histological features and by immunohistochemical findings using rabbit antiserum raised against the strain isolated from the patient.

Aged↗
PubMed1988

Sustained release of indomethacin from chitosan granules in beagle dogs.

The potential of chitosan granules as an oral sustained-release dosage form of indomethacin has been compared with conventional capsules in beagle dogs. When a commercial capsule was administered orally, the plasma concentrations reached the maximum level in 30 min. The granules did not give a sharp peak to the plasma concentration, but produced a sustained plateau of the drug. This may be due to the slow rate of release and a longer residence time in the stomach. Thus, in terms of reducing the peak in plasma concentration and maintenance of drug concentration in plasma, the chitosan granules were superior to conventional capsules.

Animals↗
PubMed1988

External control of drug release: controlled release of insulin from a hydrophilic polymer implant by ultrasound irradiation in diabetic rats.

The development of a polymeric system capable of delivering insulin in-vivo at increased rates on demand by an external ultrasound irradiation is reported. Implants composed of EVA1 copolymer and insulin were placed subcutaneously in diabetic rats. When the diabetic rats receiving implants containing insulin were exposed to an ultrasound irradiation, a sharp drop in the blood glucose levels was observed after the irradiation, indicating a rapid rate of release of insulin in the implanted site.

Animals↗
PubMed1988

[Phase II studies of a single agent and a cis-platinum-based two-drug combination in patients with non-small cell lung cancer].

Phase II studies of single agent and CDDP-based two drug combination were performed in 189 patients with inoperable non-small cell lung cancer. Six drug regimens were performed: CDDP alone, VDS alone, Epi-ADM alone, CDDP + VDS, CDDP + CPA, CDDP + ADM. The response rates were 15.4% (6/39) with CDDP alone, 8.0% (2/25) with VDS alone, 6.1% (2/33) with Epi-ADM alone, 26.7% (8/30) with CDDP + VDS, 14.3% (4/28) with CDDP + CPA, 17.6% (6/34) with CDDP + ADM and one CR was performed with CDDP + ADM. In patients with no prior chemotherapy, the response rates were 20.0% (6/30), 11.8% (2/17), 12.5% (2/16), 26.7% (8/30), 16.0% (4/25) and 25.0% (3/12), respectively. The median survival times were 25, 27, 23, 33, 25, and 45 weeks, respectively. The efficacy of CDDP in non-small cell lung cancer patients was re-confirmed, and that of CDDP + VDS, CDDP + ADM was suggested. No death due to toxicity occurred and toxicity was generally tolerable.

Aged↗
PubMed1988

[Chemotherapy of small cell lung cancer].

The recent results of chemotherapy for SCLC were reviewed in this paper. The combination chemotherapy with some highly active drugs can be summarized as follows: response rate 74-94% in limited disease (LD) and 63-90% in extensive disease (ED), complete response 39-57% in LD and 20-48% in ED, median survival 10-21 months in LD and 7-12 months in ED. To overcome drug resistance in the treatment of SCLC, non-cross resistant alternating chemotherapy has been explored. In our institute, a randomized study of continuous vs alternating regimen for SCLC was carried out from August 1982 to March 1985. This resulted in the acknowledged superiority of the alternating regimen in CR rate and the overall response rate, but no differences in survival. A current study comparing the standard chemotherapy with cyclophosphamide, adriamycin and vincristine (CAV) to alternating CAV with etoposide (E) and cisplatin (P) has suggested an advantage for alternating chemotherapy, with a statistically superior response rate and survival. The high-dose (HD) chemotherapy for SCLC is also a new strategy to improve the current treatment results. We are now studying the efficacy of HD-E (1.0-1.5 g/m2) with or without P (80-120 mg/m2) for relapsed SCLC. The result suggested that HD-E and P is an effective treatment modality as a salvage therapy. The search for new active drugs is another important way to improve the treatment results. Since 1986, a phase II study of Carboplatin has been performed in Japan. The ongoing data suggest that Carboplatin is a highly active agent against SCLC. Finally, further research will be necessary to investigate novel modalities in order to achieve a breakthrough in the current status.

Antineoplastic Combined Chemotherapy Protocols↗