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Biomedical subjects

M Kaku

Publications and source records attributed to M Kaku.

At least 235 records · Page 13Linked to original sources

[Physiologic significance of F wave in spastic paralysis in the diseases of the cerebral hemisphere].

In order to evaluate physiological significance of F-wave in the diagnosis of spasticity, 10 patients with intracranial mass lesion who did not show clinically lateralizing evidence especially in DTRs were examined and the data were compared with the results obtained from 10 other normal subjects. F-wave was recorded from thenar muscle with supramaximal stimulation to the median nerve at wrist. Latency and amplitude of F-wave failed to show any significant difference in patients compared with normal subjects both on affected sides, however, frequency of F-wave was found to be significantly higher on affected side except for 2 cases who had a mass lesion in occipital lobe in one case and the other was in the state of diaschisis due to recent hemorrhage in the parietal tumor. The site of lesion was carefully determined with CT scan and it was concluded that the F-wave could be detected quite in early stage of intracerebral mass lesion if the process had affected to internal capsule or cerebral peduncle under indirect mass effect such as cerebral edema. On the contrary, it was interesting to note that the mass with no affection to the premotor cortex likely showed higher frequency of F-wave on the ipsi-lateral side of lesion. As the conclusion, F-wave was found to have advantage in the diagnosis of spasticity in the early stage of illness and more accurate information on spasticity could be obtained compared with T or H-wave.

Brain Neoplasms↗

[Evaluation of blink reflexes in cerebellopontine angle tumors].

Blink reflexes were analysed in 28 cases with cerebello-pontine angle tumors (22 cases of acoustic neurinoma and 6 cases of meningioma). In patients with acoustic neurinoma, delay or absence of R1 was found in all but two cases (91%) and abnormality of R2 was in 11 (50%). Estimating the mean latency difference of R1 on both sides it was found useful for establishing early diagnosis of small acoustic neurinomas, which had no apparent clinical signs of facial or trigeminal nerve involvement. In patient with obsolete hemorrhage (5 cases) or large cyst (6 cases) within the acoustic neurinomas, which were proven at operation, abnormality of blink reflexes was more prominent than in patient with solid tumors (11 cases). In patients with meningioma, although all were huge tumors, abnormality of R1 was less conspicuous in comparison with acoustic neurinoma. Bilateral delay of R2 was found in 3 of 6 patients. In 13 patients who underwent spinal accessory-facial anastomosis for facial palsy after removal of the tumors, R1-like response were recorded in all but one on the affected side and R2-like response was recorded in only one patient. Observing alteration of blink reflexes in patients with cerebello-pontine angle tumor was useful for establishing early diagnosis and evaluating function of trigeminal nerve, facial nerve and brainstem.

Accessory Nerve↗

Separation of two forms of cytochrome P-450 with aryl hydrocarbon hydroxylase activity from intestinal mucosa microsomes of rabbits treated with 3-methylcholanthrene.

Two forms of cytochrome P-450, designated P-448a and P-448b, were purified from intestinal mucosa microsomes of rabbits treated with 3-methylcholanthrene. Both the cytochromes had absorption maxima at 448 nm in the carbon monoxide-reduced difference spectra. They exhibited comparable catalytic activities with benzo(a)pyrene, 7-ethoxycoumarin, and 7-ethoxyresorufin, when reconstituted with hepatic NADPH-cytochrome c reductase and phosphatidylserine. P-448a was apparently homogeneous on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and its monomeric molecular weight was estimated to be 58,000. The oxidized form had absorption maxima at 416, 512 and 571 nm, indicative of the low spin state. Thus P-448a appeared to be similar to one form of P-450, which was induced in rabbit liver by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). On the other hand, SDS-PAGE of P-448b gave a single major protein band with a monomeric molecular weight of 55,500, indicating that P-448b can be distinguished from P-448a.

Animals↗

Quantitative evaluation of plasma-opsonizing activity from the lag period of phagocytosis-connected oxygen consumption by leukocytes in whole blood.

The lag period preceding the burst of oxygen consumption by phagocytes was measured with an oxygen electrode after the addition of unopsonized zymosan in CO-treated and diluted whole blood. The duration of the lag period correlated with the phagocytic index (r = 0.98, p < 0.001). The phagocytic index was defined as the mean number of zymosan particles per phagocyte. The lag period was termed opsonizing time and used for evaluation of plasma opsonizing activity. The opsonizing time was found to be inversely related to the plasma concentration used (< 15%) and was independent of phagocyte concentration. Magnesium ions were required throughout the opsonizing time, but calcium ions were essential only during the initial phase, indicating that the alternative complement pathway plays a major role in the observed opsonizing time. The mean opsonizing times in blood from normal adults and newborn infants were 5.6 +/- 0.7 min (n = 7) and 9.1 +/- 0.7 (n = 4), respectively. The opsonizing time, expressed as its reciprocal value, correlated significantly with phagocytic index, CH50 activity, and immunochemically assayed C3, but not C4, concentration in plasma.

Adult↗

Superoxide assay-leukocyte adherence inhibition test and a soluble factor which stimulates the adherence of macrophages.

A modified method for the leukocyte adherence inhibition test is described. Peritoneal cells from immune guinea pigs or peripheral mononuclear cells from cancer patients were incubated with immunizing antigen or tumor extract in a 4-mm-wide glass microcell for spectrophotometer analysis. Instead of visual cell counting, the cells adherent to the bottom of the microcell were stimulated with cytochalasin E and wheat germ agglutinin, and the amount of the superoxide (O2.-) generated from the adherent macrophages or monocytes was assayed. Antigen-specific adherence inhibition of peritoneal cells of the immunized guinea pigs was detected 2 weeks after immunization. In contrast, cell adherence was stimulated after 3 weeks. It was shown that a soluble factor was responsible for the adherence stimulation and that nonadherent cells were necessary for its production. Peripheral mononuclear cells of 70% of the tumor-bearing lung cancer patients reacted to the lung tumor extract (9 adherence inhibitions and 7 adherence stimulations per 23 patients). Twenty-five % (3 of 12) of tumor-free patients showed positive reactions, all with adherence stimulation. Of the 12 healthy donors, 3 cases of pneumonia, one case of angiosarcoma of the left flank, one case of hemangiopericytoma of the mediastinum, and 8 cases of breast cancer, non reacted with the lung tumor extract, and only one of 7 lung tuberculosis patients showed positive adherence stimulation.

Animals↗

Establishment of a carcinoembryonic antigen-producing cell line from human pancreatic carcinoma.

A human pancreatic carcinoma cell line of islet cell origin (QGP-1) has been established and maintained for over two years. The parent tumor and the cultured cell line produce carcinoembryonic antigen (CEA), and there is no evidence of hormone secretion from the tumor cells. The epithelioid cells, which had migrated from rounded, irregular cell aggregates, grow as a confluent monolayer with piling up of cells in some areas, and have a population doubling time of 3.5 days. The modal chromosome number was 50. Exponentially growing cultures produce 76.3 ng of CEA/10(6) cells after 7 days. CEA production was confirmed by immuno-peroxidase staining.

Carcinoembryonic Antigen↗

[Intracranial high density epidermoid--classification of CT scan findings and chemical analysis of the cystic content (author's transl)].

The author described an epidermoid which revealed homogenous high density in CT scan without contrast enhancement. Sixteen reported cases of intracranial epidermoid with CT scan including our 4 cases were classified in three types; Type I; classical pearly tumor of low density with no contrast enhancement. Type II; low density mass with marginal high density ring by contrast enhancement. Type III; homogenous high density mass with no contrast enhancement. The reason of high density in CT scan was considered mainly due to the peculiar cystic content, which was brown in color and gelatinous. Chemical analysis of the cystic content disclosed various heavy metals and high protein content, however, it was indicated that the high protein concentration was solely attributable to the high density EMI number.

Brain Chemistry↗

[Traumatic aneurysm of the frontopolar artery developing after evacuation of the subdural effusion in a 6-month-old girl (author's transl)].

A 6-month-old girl developed bilateal subdural effusion after head injury. She gradually improved after the partial stripping of the membrane of the subdural effusion although postoperative tappings of the subdural fluid were necessary. Thirty nine days after the injury, she suddenly suffered from a massive intraventricular hemorrhage. A cerebral angiography showed an aneurysm arising from the proximal part of the right frontopolar artery, which had not been revealed in the previous angiograms. It was obscure whether the congenital anomaly of the arterial wall had been existed or not, but this aneurysm might be mentioned as a traumatic aneurysm and definitely developed after the treatment for the traumatic sequence. The mechanism of this aneurysmal formation was supposed that the arterial wall was initially injured by the abnormal traumatic movement of the brain underneath the falx cerebri, and teared arterial wall was further injured by the fluctuating movements of the brain caused by repeated tappings of the effused fluid. Relation of delayed posttraumatic apoplexy and ruptured posttraumatic aneurysms was also discussed, and analysis of the reported cases of the traumatic aneurysm, as well as aneurysm in the infant, was made.

Cerebral Hemorrhage↗

[Studies on cyclic 3', 5'-AMP system in human brain and its clinical application in Neurosurgical practice (author's transl)].

Literatures showed that cyclic AMP of cultured neoplastic cells of any kind was very low in concentration and also the effect of cyclic AMP and its derivatives on the malignant cells, especially on the malignant glioma, was already reported in vivo or in vitro from several neurosurgical units. The intrinsic content of cyclic AMP of the human cerebrum and the human brain tumors was first reported by authors in 1971. In this presentation the authors intended to confirm that the lower concentration of the cyclic AMP the more histologically malignant cerebral neoplasm, as well as in the cerebrospinal fluid, was observed. Concentration of cyclic AMP in the subcortical white matter, glioma, meningioma and medullobalstoma was much lower than in the gray matter tissue, however, it was not clear that the difference of the cyclic AMP concentration be possibly related to the malignancy of the human brain tumor. Furthermore, the cyclic AMP content of the cerebrospinal fluid of the patients with various brain tumor was not clearly different. The activity of adenyl cyclase was reported the highest in the synaptosome-containing fraction of the rat brain homogenate and this fact was significantly consistent with the finding that the highest concentration of the cyclic AMP was found in the human grey matter tissue. With the human brain gray matter authors determined successfully the activity of the human cerebral phosphodiesterase, which was probably localized in the post-synaptic membrane and was 158 nmole/mg protein/min. Its apparent Km was 0.9 x 10(-4) M. The results reported above have suggested the important participation of the cyclic AMP to cerebral synaptic transmission of nerve impulses, which was studied by light and electron-microscopic autoradiography utilizing the pulse labeling method with 3H-adenine. According to our study the majority of the adenyl cyclase of the human cerebrum was located synaptic structure and the finding obtained was quite compatible, as the first morphological study, with previously reported biochemical analyses. It was indicated that the cyclic AMP in the human brain was concerned to the cerebral synaptic transmission of nerve impulses and this should be very interesting and important to the clinical application for recovering cerebral function of neurosurgical patients.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗