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Biomedical subjects

S Murayama

Publications and source records attributed to S Murayama.

At least 217 records · Page 12Linked to original sources
PubMed1987

Neurofibrillary tangles in human upper cervical ganglia. Morphological study with immunohistochemistry and electron microscopy.

Neurofibrillary tangles (NFTs) are one of the main pathological hallmarks of Alzheimer's disease or senile dementia, and are seen in the cerebral cortex and some other nuclei in the central nervous system (CNS). No NFTs have been reported in the human peripheral nervous system, although NFTs were recognized in the dorsal root ganglion of the aged rodents. We report here the presence of NFTs in the upper cervical ganglia (UCGs), but not in the stellate nor in the celiac ganglia, of an elderly patient, who was not demented and had only minimal senile changes in the CNS. Immunohistochemically the antibodies to microtubule-associated protein 2, paired helical filaments and ubiquitin stained positively the NFTs in the UCGs. On electron microscopic examination a periodical twisted pattern of the filaments was identified; these findings suggest that the NFTs of the UCGs have just the same properties as those of the cerebral cortex. This is the first report of the demonstration of NFTs in the peripheral ganglia and might contribute to the study of mechanism of NFT production.

Aged↗
PubMed1987

Action of botulinum neurotoxin on acetylcholine release from rat brain synaptosomes: putative internalization of the toxin into synaptosomes.

The action of botulinum neurotoxin type C1 on the release of acetylcholine from rat brain synaptosomes was studied by using anti-toxin heavy chain Fab and anti-toxin light chain Fab. The toxin was bound to synaptosomes at 0 degrees C for 10 min, in which [14C]acetylcholine had been accumulated previously. The toxin-binding synaptosomes were pre-incubated at 37 degrees C, and the release of acetylcholine was determined after the synaptosomes had been incubated in 25 mM KCl-incubation medium for 20 min at 37 degrees C. Inhibition of [14C]acetylcholine release from the synaptosomes was observed with increasing pre-incubation time and toxin concentration, and the maximum inhibition was seen after pre-incubation for at least 15 min, which was called the "lag time." The toxin-binding synaptosomes were reacted with anti-toxin heavy chain and anti-toxin light chain Fabs at 0 degrees C for 1.5 min before pre-incubation of the synaptosomes at 37 degrees C. Both Fabs reversed the acetylcholine release inhibition by the toxin. However, when the Fabs were added during the pre-incubation time at 37 degrees C, they showed less restoration with increasing pre-incubation time. The restoration was completely abolished if the Fabs were added to the synaptosomes after the first half of the "lag time." On the other hand, when 125I-labeled toxin-binding synaptosomes were reacted with the Fabs at 0 degrees C for 1.5 min before pre-incubation of the synaptosomes at 37 degrees C, anti-heavy chain Fab removed 125I-toxin from the synaptosomes, but anti-light chain Fab did not. However, if the Fabs were added to toxin-binding synaptosomes during the pre-incubation time at 37 degrees C, the Fabs could not remove 125I-toxin from the synaptosomes, and the synaptosomes retained more labeled toxin with increasing pre-incubation time. These results suggest that there are three distinct steps in the inhibition of acetylcholine release from synaptosomes by botulinum neurotoxin. The first is binding, which is reversible, temperature-independent, and mediated by the heavy chain of the toxin. The second is temperature-dependent internalization, that takes place in the first half of the "lag time," in which both the chains are internalized into synaptosomes. The third is the development of toxicity, which requires the latter half of the "lag time."

Acetylcholine↗
PubMed1987

[Basic evaluation of highly sensitive thyroid stimulating hormone immunoradiometric assay kits].

Usefulness of three kinds of TSH kits by immunoradiometric assay (IRMA) was evaluated. They were able to measure low levels (less than 0.1 microIU/ml) in serum thyroid stimulating hormone (TSH) with incubation of short time (4 hours). In particular, RIABEAD II kit had a highly specific affinity for TSH and the normal range (+/- 2 S.D.) using it showed from 0.20 to 3.50 microIU/ml in 150 normal subjects. In patients with hyperthyroidism and in patients with hypothyroidism, the values of TSH were lower and higher than those of normal subjects, respectively. Another kits showed similar results. These results indicate that these TSH-IRMA kits are useful to evaluate serum TSH levels exactly.

Evaluation Studies as Topic↗
PubMed1986

[Imaging diagnosis of hepatobiliary system and pancreas--computed tomography, ultrasound and angiography].

CT, US and angiography have become the most important examinations in the diagnosis of hepatobiliary and pancreatic diseases. Therefore updated and precise knowledge of these modalities are mandatory not only for the diagnosis but also for the interventional radiology in this field. General review on the advantages and limitations of these medical images are described.

Angiography↗