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Biomedical subjects

N Moriyasu

Publications and source records attributed to N Moriyasu.

At least 19 recordsLinked to original sources
PubMed1982

[Epiplexus cell (Kolmer cell) and its reaction against foreign bodies].

In 1921, Kolmer reported the free cell which is characteristically anchoring to the surface of the choroid plexus by its pseudopodal cytoplasmic processes, and later named "Kolmer cell". Phagocytic function of this cell was reported by Ariëns-Kappers in 1953, and he called this cell to "epiplexus cell". In this paper, the epiplexus cell of adult dog was studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), and its ultrastructure, reactions and changes against foreign bodies are described. Furthermore, obstructed ventricular catheter by choroid plexus in clinical ventricular shunt operation was observed by SEM. The structure and nature of the epiplexus cell resembles that of macrophages in other tissue. When small foreign bodies such as ink particles or red blood cells were injected into the ventricle, the reaction of the epiplexus cells was observed as an increase in their number and phagocytosis. And against the large foreign bodies, such as small strips of silicon rubber tube, a remarkable increase of the epiplexus cells were seen. These proliferated cells had many long cytoplasmic processes and laid in piles. In these above-mentioned results, we considered that the proliferative and phagocytic reaction of the epiplexus cell represents one of the causes of ventricle catheter obstruction.

Animals↗
PubMed1981

Evidence for involvement of the frontal cortex in pain-related cerebral events in cats: increase in local cerebral blood flow by noxious stimuli.

Noxious stimuli were shown to induce a remarkable increase in local cerebral blood flow restricted to the forepart of the cerebral hemispheres bilaterally anterior to the posterior sigmoid gyrus in cats. This increase in local cerebral blood flow was averted by lesions in the bilateral ventromedial thalamus and attenuated by pretreatment with an intraventricular injection of 6-hydroxydopamine.

Animals↗
PubMed1981

[Infusion test in the normal pressure hydrocephalus (author's transl)].

Continuous monitoring of the intracranial pressure and ventricular infusion test were carried out in 13 cases in which normal pressure hydrocephalus (NPH) was suspected. The infusion test was performed by intraventricular bolus injection of 8 ml of saline. The result was collated with the effect of shunting operation, which was judged by means of the improvement in the clinical symptoms and the amplitude of contingent negative variation. The excellent effect of shunting operation was obtained in the patients who showed the T of more than 200 sec, the compliance of less than 1.0 ml/mmHg, the conductance to outflow of less than 0.8 ml/mmHg/min and CSF outflow resistance of more than 15 mmHg/ml/min. In 3 cases out of the 5 effective cases, A or B wave was seen. However, appreciable variation of the values was shown among the cases so that it was concluded that the all-round-consideration must be done to select the case for the shunting operation with the findings in RI-cisternography, pneumoencephalography, computerized tomography and so on. This fact might indicate the existence of the complicated pathophysiology in NPH resulted from not only the impairment of cerebrospinal fluid circulation but also the disturbance of cerebral blood flow, changes in plasticity of the brain and so on.

Adult↗
PubMed1980

Changes in local cerebral blood flow and neuronal activity during sensory stimulation in normal and sympathectomized cats.

Activities of neurons of the thalamic relay nucleus and cortical somatosensory area which are capable of producing excitatory potentials in response to stimulation of the sciatic nerve were recorded, and local cerebral blood flow was measured simultaneously using a double microelectrode under local anesthesia in both non-pretreated cats and cats undergoing chemical denervation of the vasoadrenergic nerves by intraventricular injection of 6-hydroxydopamine (6-OHDA), in order to unmask the neural control on the cerebral vessels during increase of local metabolic rate. The results obtained may be summarized as follows. (1) A positive correlation was found between an increase in firing rate of a single neuron in the thalamic relay nucleus and somatosensory area and an increase in local cerebral blood flow following stimulation of the sciatic nerve. A distinct spatial and quantitative correlation was thus observed between neural activity and cerebral blood flow. (2) In 6-OHDA-pretreated cats, an increase in neuronal firing rate was observed following stimulation of the sciatic nerve, as it was in non-pretreated cats, but the concurrent response of local cerebral blood flow was seriously impaired. All these findings indicate that the increase in local cerebral blood flow occurring in association with increased neural activity does not result solely from increased local metabolism and a consequent increase in CO2 production, but requires for its occurrence that certain basic conditions be satisfied and maintained by the vasoadrenergic innervation.

Adrenergic Fibers↗
PubMed1980

Assessment of brainstem damage by the auditory brainstem response in acute severe head injury.

In 64 cases suffering from severe head injury (Glasgow coma scale: less than seven- the auditory brainstem responses (FARs) recorded at the vertex, which are thought to be volumet conducted far-field potentials reflecting the sequential electrical activities of the auditory afferen) system in the brainstem, were recorded in the neurosurgical intensive care room immediately after admission. The alterations in the responses were compared with the types of primary injury, neurological signs., CT findings and outcome following treatment. Based on the results obtained, it is concluded that the FAR is a useful indicator for predicting the effects of treatment on brainstem damage in patients with severe head injury, and that it provides more reliable information about the function of the brainstem than the neurological signs or CT findings. Moreover, it also offers a diagnostic method for primary brainstem injury. Three cases or primary brainstem injury without lesions in the supratentorial region were diagnosed by means of combined CT and FAR recording.

Adult↗
PubMed1980

Sacral epidermoid cyst communicating with the spinal CSF canal.

A 6-year-old girl was found to show a presacral epidermoid cyst which had a communication with the spinal canal. The patient was admitted as a case of meningitis, but squamous cells and cholesterin crystals were observed in the cerebrospinal fluid (CSF), and the CSF cholesterol level was very high. Diagnosis was established by myelography, and a cyst measuring 4.5 x 6.0 x 4.0 cm wide was totally excised surgically. A comparative discussion of this case and other reported cases of dermoid and epidermoid cysts in the central nervous system is given.

Child↗