Silicon intake to vertebral columns of mice after dietary supply.

Vertebral columns were dissected and analyzed after birth with oral administration of silicon for 4 wk and for 8 wk. The silicon level was lower (20 microg/g) at the beginning. It remains unchanged after 4 wk and then increases twice as much as that for those mice bred for 8 wk than those bred for 4 wk. This increase depends remarkably on the mass ratio of Si/Ca (M/M). The ratio increases to three times higher than that of the control at the beginning of the experiments (5 wk after birth). Although the S and P contents appeared to be lower, these increased when Si was administered in combination with phosphopeptide. Other elements, such as Ca, Mg, Fe, and Zn, appeared to be unchanged as the weeks proceeded. These findings seem to support a proposal that silicon is necessary for the growth of backbones in mice.

Age-dependent increases of calcium and phosphorus in human epiglottal cartilage.

To elucidate compositional changes of the elastic cartilage with aging, the authors investigated age-related changes of elements in the epiglottal cartilages by inductively coupled plasma-atomic emission spectrometry. After the ordinary dissection by medical students at Chiang Mai University was finished, the epiglottises were resected from the subjects. The epiglottal cartilages were isolated and the element contents were determined. The subjects consisted of 11 men and 14 women, ranging in age from 39 to 92 yr old. It was found that although the extent of accumulation of calcium and phosphorus was slight, calcium and phosphorus increased progressively in the epiglottal cartilages with aging. In contrast, sulfur, magnesium, zinc, iron, and sodium did not change significantly in them. Regarding the relationships among elements, it was found that there were significant correlations among calcium, phosphorus, magnesium, and sodium in the epiglottal cartilages, with one exception between calcium and sodium contents. In comparison between men and women, no significant differences were found in the predominant elements such as calcium, sulfur, and phosphorus in the epiglottal cartilages.

Increases of calcium and magnesium and decrease of iron in human posterior longitudinal ligaments of the cervical spine with aging.

To elucidate compositional changes of ligaments with aging, the authors investigated age-related changes of elements in the posterior longitudinal ligaments (PLLs) by inductively coupled plasma-atomic emission spectrometry. After the ordinary dissection, PLLs were resected from the subjects ranging in age from 65 to 95 yr. The PLLs of the cervical spine were resected between the fourth and fifth cervical vertebrae, the PLLs of the thoracic spine between the fifth and seventh thoracic vertebrae, and the PLLs of the lumbar spine between the second and third lumbar vertebrae. Calcium and magnesium increased progressively with aging in the PLLs of the cervical spine, but they did not increase with aging in the PLLs of the thoracic and lumbar spine. In contrast, iron decreased gradually with aging in the PLLs of the cervical spine. Regarding the relationships among elements, significant correlations were found among the contents of calcium, phosphorus, magnesium, and sodium in the PLLs of the cervical spine.

Age-related changes of elements and relationships among elements in the common bile and pancreatic ducts.

To elucidate compositional changes of the common bile and main pancreatic ducts with aging, the authors investigated age-related changes of element contents in the common bile and pancreatic ducts by inductively coupled plasma-atomic emission spectrometry. After ordinary dissection by medical students was finished, the common bile ducts and main pancreatic ducts (pancreatic ducts) were resected and the element contents were determined. The Mg content increased significantly only in the pancreatic duct with aging, but the other element contents did not change significantly in both the common bile and pancreatic ducts with aging. Regarding the relationships among the elements, significant direct correlations were found among the contents of Ca, P, S, and Mg in the common bile ducts, with some exceptions between P and either S or Mg contents. In the pancreatic ducts, significant direct correlations were found between S and Mg contents and between P and Na contents. The relationships in the elements between the common bile and pancreatic ducts were examined. It was found that there were significant direct correlations in the Ca, Mg, and Fe contents between the common bile and pancreatic ducts; that is, as Ca, Mg, and Fe increased in the common bile duct, they increased simultaneously in the pancreatic duct.

Age-related changes of elements with their relationships in human cranial and spinal nerves.

To elucidate compositional changes of peripheral nerves with aging, the authors investigated age-related changes of elements and their relationships in the optic, trigeminal, vagus, median, radial, ulnar, femoral, sciatic, tibial, and common peroneal nerves by inductively coupled plasma-atomic emission spectrometry. The subjects consisted of 10 men and 12 women, ranging in age from 65 to 91 yr. It was found that although accumulations of Ca and P occurred only in the trigeminal nerve at old age, it hardly occurred in the optic, vagus, median, radial, ulnar, femoral, sciatic, tibial, and common peroneal nerves at old age. The average contents of Ca and P were three and two times higher in the trigeminal nerve than in the other nine kinds of nerve, respectively. Likewise, the average content of Mg was a little higher in the trigeminal nerve compared with the other nerves. With regard to the relationships among elements, significant direct correlations were found among the contents of Ca, P, S, and Mg in most, but not all, 10 kinds of nerve. In the trigeminal nerve, a significant inverse correlation was found between the contents of S and the other elements, such as Ca, P, and Mg. Regarding the relationships between the contents of S and other elements, the nerves, except for the trigeminal nerve, differed from those found in the arteries previously reported.

Silicon compatible with the height of human vertebral column.

In the study on human vertebral composites, silicon was found to be related to the height of the vertebral column. The element ratio of silicon to calcium in the lumbar vertebra was twice that of the lowest one in the cervical vertebra. The element ratio gradually increased from approx 0.5 at the cervical vertebra to approx 1.0 at the lumbar one. Silicon is preserved catastropically much more in the lower height of the backbone in contrast with the calcium amount, and the ratio to sulfur appears to be unchanged. This suggests that silicon is compatible with the biokinetics of the vertebral bone structure of calcium.

A special comment on trace metals in the viscera of turbo marmoratus, a toxic snail, on Ryukyu Island.

Trace metals in the viscera of Turbo marmoratus, a huge conical spire, in the coral reef of Ryukyu Island were analyzed. The highest amount of Zn and Fe was detectable in the midgut gland known to be polluted by saxitoxin. This intestine maintained a considerable amount of Si (higher than Ca) which fluctuated in parallel with the taurine amount. These data suggest that the viscera of the alimentary tract accumulate some metals, especially Zn and Fe.

Differences in calcium accumulation between human plantar and palmar aponeuroses.

To elucidate the characteristics of calcium accumulation of human plantar and palmar aponeuroses, the authors determined the calcium content of human plantar and palmar aponeuroses by atomic absorption flame emission spectrophotometry. The subjects consisted of 9 men and 14 women, ranging in age from 61 to 93 yr. In the plantar aponeurosis, the calcium content was significantly higher in the anterior and posterior parts than in the middle part. It is known that pressure distribution under the sole of a foot is higher in the anterior and posterior parts than in the middle part. The present study suggests that the accumulation of calcium in the plantar aponeurosis is related with the pressure distribution under the sole of a foot. The calcium content increased progressively with aging in the anterior part of the plantar aponeurosis, but not in the middle and posterior parts. Regarding the palmar aponeurosis, the calcium content was significantly higher in the anterior and posterior parts in comparison with the middle part. It was found that the calcium content increased progressively with aging in the posterior part of the palmar aponeurosis, whereas it did not increase significantly with aging in the anterior and middle parts. Regarding the relationship between the calcium content of the aponeuroses and the bone mineral density, a significant correlation was found between the calcium content in the anterior part of the palmar aponeurosis and the bone mineral density of the scaphoid bone.