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Biomedical subjects

M Segawa

Publications and source records attributed to M Segawa.

At least 181 records · Page 10Linked to original sources
PubMed1979

Self-mutilation and sleep stage in the Lesch-Nyhan syndrome.

Correlation of self-mutilation and sleep stage in the Lesch-Nyhan syndrome was studied by a polygraphic method. Five patients and three control boys were monitored with EEG, EOG, EMG, ECG and respiration throughout the night. The results were as follows: 1. The sleep-time of the patients was much disturbed during the night. 2. Decreased REM density was noticed with low DQ of the patients. 3. Self-mutilation during sleep-time was observed a lot in stages 1, 2, and REM in two cases. 4. No correlation was observed between body movement and self-mutilation in the Lesch-Nyhan syndrome. These data suggested functional disorders of the frontal lobe in the patients.

Adolescent↗
PubMed1978

Malignant melanoma of the gallbladder.

A rare case of primary malignant melanoma of the gallbladder was studied with the electron microscope. Two interesting patterns were observed: numerous melanophages were present in the tumor tissue and wrapped compound melanosomes were found in nonneoplastic mucosal epithelium. The infiltration of melanophages was considered to be a reaction to degenerated tumor cells. Concerning the mechanism of melanosome transport into the epithelial cells, a cooperative action between epithelial and melanoma cells seemed to be the most important factor.

Aged↗
PubMed1978

Induction of sister chromatid exchanges by transformation with simian virus 40.

The frequency of sister chromatid exchange (SCE) has been followed sequentially after the addition of SV40 to human diploid fibroblast cultures. The SCE frequency was nearly the same in uninfected controls and in infected cultures before they became tumor antigen positive. When cells exhibited tumor antigen, the SCE frequency increased over a wide range, and changes in chromosome number and structure were observed simultaneously. Cells with induced chromosome abnormalities without increased SCE's and the reverse present the possibility that the two phenomena have different viral mechanisms. This increase in SCE can be added to the previously demonstrated change in chromosome number and increase in chromosome breakage and rearrangement as indicators of genetic damage associated with viral transformation.

Antigens, Viral↗
PubMed1977

Screening for autosomal aberrations.

A method of screening for autosomal aberrations is important as an indication for chromosome analysis such as that used in sex-chromatin examination for sex chromosome aberrations. In our clinic, malformed patients with mental retardation and abnormal dermatoglyphic patterns are strong suspects for autosomal aberrations. Abnormal dermatoglyphic patterns are separated into two categories: (1) Absolutely abnormal--radial loop of 1st finger, radial loop of 4th finger, radial loop of 5th finger, arch over 6 fingers, arch tibial, loop tibial, and arch fibular; (2) Borderline abnormalities--high axial triradius (t' and t"), simian crease, interdigital loop, and single crease of 5th finger. Of 416 cases showing malformation, retardation, and abnormal dermatoglyphics, 308 had autosomal aberrations, while 108 had normal karyotypes. In the group with autosomal aberrations, 279 patients (90.6%) had absolutely abnormal dermatoglyphics. In the group with normal karyotypes only 8 patients (7.4%) had absolutely normal dermatoglyphics, while most had abnormal dermatoglyphics in the borderline category. These clinical manifestations: absolutely abnormal dermatoglyphics, mental retardation, and malformations are therefore very useful in screening for autosomal aberrations.

Abnormalities, Multiple↗
PubMed1976

Congenital muscular dystrophy as a disease of the central nervous system.

Profound abnormalities of the brain were noted in a 6-year-old Japanese boy with congenital muscular dystrophy (CMD). Pathological alterations included diffuse cerebral and cerebellar micropolygyria, with bilateral temporal agyria, and abnormal fusion of gray matter in the basal portions of both frontal hemispheres. Microscopically, the architecture of both cerebral and cerebellar cortices was severely distorted, with irregular arrangement of neurons and increased vascularization. Skeletal muscles showed dystrophic changes rather than neurogenic atrophy. Eight autopsy cases of CMD with similar pathologic findings have been reported in Japan, although the lesions in the brain are quantitatively different from case to case. The findings indicate that CMD is a dysplastic disease of the central nervous system, with dystrophic involvement of skeletal muscles.

Brain Diseases↗