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Biomedical subjects

M Osaka

Publications and source records attributed to M Osaka.

70 records · Page 4Linked to original sources
PubMed1980

Human intelligence and power spectral analysis of visual evoked potentials.

The relationship between intelligence and power spectra of visual evoked potential was investigated using 8 normal and 8 mentally retarded children as subjects. The results showed the power spectrum of mentally retarded has a peak at 4 to 6 Hz, whereas that of normal has two apparent peaks at 4 and 12 Hz. It appears the peak at 12 Hz reflects the difference of intelligence.

Adolescent↗
PubMed1979

Spectral analysis of EEG during mental activity (author's transl).

With the use of power spectral analysis, the occipital and frontal EEGs in normal young subjects were examined during mental activity under closed-eye and open-eye conditions. Under the closed-eye condition, the peak of power spectral density in the alpha band was suppressed during mental activity, as compared with the finding obtained without mental loading. Moreover, the peak frequency of the alpha band shifted to higher frequencies under the mental loading condition in all of the subjects. Under the open-eye condition, alpha waves were prominently suppressed and no peak of power spectral density in the alpha band could be detected. However, during mental activity the peak of power spectral density could be detected in the delta wave band of both occipital and frontal EEGs.

Adolescent↗
PubMed1975

On the possible role of intestinal hormones as the diarrhoeagenic messenger in cholera.

Cholera enterotoxin introduced into the duodenum of young rabbits causes severe degranulation of the enterochromaffin (EC) cells as revealed by electron microscopy. In the mucosal epithelium fixed mainly 1 hr after toxin administration, many of the basal granules of the EC cells are swollen up and open to the basal and lateral cell surface. The EC cells of the rabbit, as it is the rule for intestinal endocrine cells in mammals, are open to the lumen with an apical process covered by microvilli. A hypothesis is proposed that cholera toxin stimulates this apical receptor of the EC cells and that the aminic (serotonin) and polypeptide (motilin?) products of the cells released by the stimulus may mediate the diarrhoeagenic action of cholera enterotoxin.

Animals↗
PubMed1975

Fine structure of the basal-granulated cells in human fetal duodenum.

Fine structure of the duodenal mucosa in ten human fetuses 4 to 7 months old was studied by light and electron microscopy using Epon-embedded specimens. Cells containing membrane-bound granules were found both in the connective tissue and in the epithelia and identified to be basal-granulated cells, since they essentially corresponded in their cytoplasmic fine structures to the named cells in the adult. However, their relation to nerves and epithelial elements revealed some primitive features. In the 4 month fetus, the basal-granulated cells were seen in the lamina propria forming clusters which were often in contact with the basal part of the epithelium. In the 5 month fetus, occurrence of clustered basal-granulated cells in the connective tissue was among other epithelial cells, gaining an apical process which reached the lumen. The basal-granulated cells in the lamina propria were frequently surrounded by a Schwann-like cell. Profiles of unmyelinated nerve fibers were ample in the space between the Schwann-like cell and the basal-granulated cell. An phi-shaped invagination of the basal plasma membrane encompassing granular material was often found in the D type basal-granulated cells in the 7 month fetus. This suggests that the secretion of at least some of the basal-granulated cells starts in the prenatal period by emiocytosis.

Cytoplasmic Granules↗
PubMedDate not supplied

Gut-endocrinomas (carcinoids and related endocrine variants) of the breast: an analysis of 310 reported cases.

The purpose of this study was to analyze the present status of gut-endocrinomas (carcinoids and related endocrine variants) of the breast, an extremely rare site for primary growth of such neoplasms, and to provide precise and reliable information concerning these neoplasms on varying clinicopathological aspects for investigators engaged in relevant research fields. A total of 310 cases presented in this analysis consisted of 196 carcinoids, 102 typical and 94 atypical, and 114 related endocrine variants; in the last group, the expression of "breast carcinoma with (neuro-) endocrine differentiation" was often used without referring to the term "carcinoid." A statistical evaluation was performed on most occasions based on a comparison among three groups of typical carcinoids, atypical carcinoids and related endocrine variants, or between the former two series of carcinoids and the third series of endocrine carcinomas. Statistically significant differences between the groups of carcinoids and endocrine carcinomas were recognized in terms of average age, tumor size categories of < or = 20 mm and 21-50 mm, rates of metastases, and positive neuron-specific enolase (NSE) immunohistochemistry. Contrary to our expectations no statistically significant difference between these two groups was evident in terms of overall average tumor size, Grimelius argyrophilia for endocrine nature, or postoperative 5-year survival rates in curative resection cases. It seems important to establish more precise diagnostic criteria for "endocrine carcinomas" from the viewpoint of a certain possibility that some of these neoplasms may belong to the atypical carcinoid group.

Aged↗