Biomedical subjects

Y Tohno

Publications and source records attributed to Y Tohno.

77 records · Page 5Linked to original sources

PubMedDate not supplied

Age-dependent changes of mineral contents in men and women's calcanei.

To elucidate age-related change of mineral contents in human bones, the mineral content and density of human calcanei were determined by inductively coupled plasma atomic emission spectrometry and dual-energy X-ray absorptiometry. Calcanei were removed from 27 subjects (17 men and 10 women) who died in the age range from 40-98 yr old. Both the inductively coupled plasma emission spectrometry and dual-energy X-ray absorptiometry indicated that there were age-dependent decreases of the mineral contents and density in the men's calcaneus in the age range from 40-98 yr, but not in the women's calcaneus in the age range from 42-87 yr. It was also found that the calcanean masses of the men and women remained constant within the same age range until 98 yr.

Absorptiometry, Photon↗

PubMedDate not supplied

Age-dependent aluminum accumulation in the human aorta and cerebral artery.

The purpose of this study was to determine the extent of aluminum (Al) accumulation in the human aorta and cerebral arteries. The Al contents in the aortae and in the cerebral arteries from 23 human subjects was determined by inductively coupled plasma atomic emission spectrophotometry (ICP-AES). The subjects' age range was 45-99-yr-old; 15 of the subjects were males and 8 were females. Al was detected in twelve aortae and in six cerebral arteries, when the entire specimen was analyzed. Two specimens where Al was found in the cerebral arteries contained no Al in the aorta. No relationship to the subject's sex was found. When related to age, two groups were established. Group L (45-75 yr old) and group H (> 75 yr old), which exhibited aortal Al concentrations of 33.3 and 72.7%, respectively. When the aortic wall was dissected into the tunica intima, media, and adventitia, Al was found mainly in the tunica media. In the aorta, significant relationships were found between Al and phosphorus (P) levels (r = 0.801, p < 0.01) and between Al and calcium (Ca) (r = 0.661, p < 0.05). We have concluded that Al accumulation is age-dependent and that it occurs both in the aorta and in the cerebral artery. In the aorta, accumulation occurs mainly in the tunica media. Both P and Ca appear to enhance aortal Al accumulation.

Aged↗

PubMedDate not supplied

A high accumulation of minerals in human internal jugular vein.

To elucidate age-related changes of mineral contents in human veins, the relative contents (RCs) of elements in the human internal jugular veins, superior and inferior venae cavae, and femoral veins from 27 subjects ranging from 40 to 98 yr old were analyzed by inductively coupled plasma atomic emission spectrometry. The average RCs of calcium in the 27 specimens were the highest in the internal jugular vein, followed in descending order by the superior vena cava, femoral vein, and inferior vena cava. The RCs of calcium and phosphorus in the internal jugular veins started to increase after the age of 50 yr, became the highest in subjects in their 60s and thereafter decreased gradually. It is noted that such accumulations of minerals, similar to the internal jugular vein, were also found in the veins, such as the superior and inferior venae cavae, and femoral vein. Accumulation of minerals in the veins is different from that of arteries, which increase progressively by aging, but do not decrease.

Adult↗

PubMedDate not supplied

Tissue platinum after clinical treatment with cisplatin or carboplatin in tumor-bearing patients.

Tissue platinum (Pt) levels were measured in tumor-bearing patients treated with either cisplatin or carboplatin. Cisplatin was given by intra-arterial, intraperitoneal, and intravenous (iv) administrations. After death, vertebrae and intervertebral disks were removed from eight human subjects, and livers and kidneys were removed from the half of them. When cisplatin was administered intraperitoneally, Pt of the liver was higher than that of the kidney, and a high content of Pt was detected in the vertebra by comparing with the other administration methods. At the intra-arterial administration of cisplatin, Pt was mainly accumulated in the kidney. At the iv administration of cisplatin, a high level of Pt was found in the vertebra and intervertebral disk, especially at the highest value at 10.31 micrograms/g in the intervertebral disk of one case, whereas a low level of Pt was detected in the liver. On the contrary, it was found that the iv administration of carboplatin did not result in high accumulations of Pt in the liver, kidney, intervertebral disk, and vertebra. Therefore, Pt is accumulated in different organs, depending on the way cisplatin is administered, but Pt is accumulated least in them by the administration of carboplatin.

Adult↗

PubMedDate not supplied

Chromatin fiber loops protruded artificially from nuclei of rat ascites hepatoma cells.

To determine the size and location of supranucleosomal fibers, the isolated and swollen nuclei from rat ascites hepatoma cells were broken mechanically by a homogenizer, and the broken nuclei were observed with an electron microscope, with and without treatment with detergent Joy. The observation of the broken nuclei treated with 0.06% Joy demonstrated that most, but not all the protruded chromatin, had a loop structure. Protrusion of chromatin from nuclear fragments was estimated to be about 0.77 microns in length. The conformation of protruded chromatin mainly consisted of supranucleosomal fiber, and a little of nucleosomal fiber. Electron microscopy also indicated that an anchorage of chromatin was nuclear lamina. Therefore, chromatin loop size of supranucleosomal fiber (solenoid) was about 1.54 microns in length, corresponding to nucleosomal fiber of about 9.24 microns in length.

Animals↗