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Biomedical subjects

J Okada

Publications and source records attributed to J Okada.

At least 217 records · Page 12Linked to original sources
PubMed1981

Cardiac and non-cardiac preganglionic neurones of the thoracic vagus nerve: an HRP study in the cat.

Using the HRP method, we studied cardiac and non-cardiac preganglionic neurones of the thoracic vagus nerve in the cat. The inferior cardiac branches of the right thoracic vagus nerve were differentiated from the neighboring non-cardiac branches by positive cardiac slowing following electrical stimulation. A small amount of crystalline HRP was placed at the central cut end of the cardiac or non-cardiac branches. After a survival period of 2 days, the medulla oblongata, the stellate ganglion (SG), the superior cervical (SCG) and the nodose ganglion (NG) were serially sectioned and processed for histochemical demonstration of HRP. In the medulla oblongata, HRP-labeled cells were mainly located in 2 regions: (1) within and around the ambiguous complex (site A); (2) within the dorsal vagus nucleus (site X). After applying HRP to the cardiac branches, 968 HRP-labeled cells were observed in 7 animals bilaterally with the ipsilateral dominance (94%); 81% of them were found in site A. After applying HRP to the non-cardiac branches, 447 HRP-labeled cells were seen in 2 animals bilaterally with the ipsilateral dominance (92%); 79% of them were found in site X. Many HRP-labeled cells were found in the SG and NG, indicating that the cardiac branches are composed of sensory afferent and sympathetic efferent fibres as well as cardiac vagus efferent fibres.

Animals↗
PubMed1980

Evaluation of brain tumour laser surgery.

A surgical carbon dioxide laser unit (laser) has been used since 1977 in twenty-five cases of various brain tumours, including ten meningiomas (four sphenoid ridge, two parasagittal, two falx, one olfactory, one posterior fossa), eleven gliomas (seven glioblastoma, four astrocytoma), two metastatic brain tumours, one haemangioblastoma, and one arteriovenous malformation (AVM). The criteria for laser use, as based on evaluation and location of meningioma, were: grade 1, convenient but adjuvant; grade 2, also necessary; grade 3, indispensable. The laser is obligatory in sphenoid ridge meningioma in order to peel the tumour away from the internal carotid artery, middle cerebral artery, cavernous sinus ect. The grade of necessity for laser use is therefore either 2 or 3. In convexity or parasagittal meningioma, on the other hand, the necessity grade is either 1 or 2. In the glioma group hemorrhage in seven cases of glioblastoma was easily laser-controled, and the tumours were wasted away in a short time through vaporization, with minimum mechanical effect on adjacent tissue. The laser is therrefore very useful in cases of glioma, especially glioblastoma, considering the shortened operating time, decreased blood loss, and extended area of tumour resection. Laser surgery is proposed as being most appropriate, mainly for its vaporizing and coagulating functions, in cases of brain tumour involving the elderly and poor risk cases.

Adult↗
PubMed1980

[Three cases of traumatic intracerebral hematoma with ventricular hemorrhage (author's transl)].

Three heavy drinkers, the patients fell down stairs while inebriated and were hit on their heads. Utilizing CT, we found that the hematomas in all three cases were accompanied by ventricular hemorrhage which, in two of the cases, were similar to hypertensive intracerebral hematoma in the basal ganglia. None of the three had a history of hypertension. We are of the opinion that the vulnerability of cerebral arteries, especially in the basal ganglia, of such heavy drinkers added to the traumatic force and led to the pathogenic bleeding. We were unable to find a correlation between the intracerebral hematoma and the site of the hit. It is assumed that immediate removal of the hematoma in cases of intracerebral hematoma with ventricular bleeding can result in the survival of the patient.

Adult↗
PubMed1980

[Evaluation of laser surgery against brain tumor (author's transl)].

UNLABELLED: A surgical carbon dioxide laser unit (Laser) has been used in 26 cases of various brain tumors, including 10 meningioma (4 sphenoid ridge, 3 parasagittal, 1 falx, 1 olfactory, 1 posterior fossa); 12 glioma (7 glioblastoma, 5 astrocytoma); two metastatic brain tumors; 1 hemangioblastoma, and 1 AVM. Criteria for Laser use based on evaluation and location of meningioma were: grade 1, convenient but adjuvant; grade 2, also necessary; grade 3, indispensable. Most meningioma in convexity and parasagittal were grade 1-2, with those in the sphenoid ridge grade 2-3. In the glioma group, hemorrhage in 3 cases of glioblastoma was easily Laser-controlled, and the tumors wasted away in a short time with vaporization. There was minimal mechanical effect on the adjacent tissue. CONCLUSION: In neurosurgery, Laser is obligatory in sphenoid ridge meningioma to dissect the internal carotid artery, middle cerebral artery, cavernous sinus, sphenoid ridge, etc. It is very useful in glioma, especially glioblastoma, considering shortened surgical duration, decreased blood loss and extended tumor resection. Laser surgery is proposed as most appropriate for brain tumors in elderly and poor risk cases mainly for its vaporizing function.

Adult↗