Japanese serow, Horn, Hydroxyapatite, Trace elements, Mineral deposition Summary: The Japanese serow (Capricornis crispus) is protected as a special natural monument in Japan. The ring count of the soft X-ray photographs of Japanese serow horn was found to be a useful criteria to determine the ages exactly. The mineralization process in Japanese serow horn was examined microscopic, ICP and X-ray diffraction methods. The incremental lines appeared as light and dark layers in the section stained for fuchsin and methylen blue. Mineral depositions were observed among the keratin fibers, no matrix vesicle in the electron dense regions. X-ray diffraction pattern of crystalline inorganic components in Japanese serow horn was determfined as β-tricalcium phosphate (TCP), hydroxyapatite (HA) and unknown phase. ICP measurement was also carried out. The horn contained trace elements of K besides Na, Ca, Fe and P. The Ca/P molar was found to be 2.9. The ratio was much higher than the theoretical value of HA. Presumably, keratin was the seed which might be related to mineralization and higher Ca activity was detected in the initial phase of epitaxial growth. Analytical results of the measurement of trace elements in Japanese serow horn by using ICP method seemed to be correlated with the evaluation of environmental conditions. The present study indicated that the mineralization of Japanese serow horn directly related with deposition Ca-deficient HA among the keratin fibers.

View full abstract

Two anomalous cases of the right subclavian artery were found in Japanese cadavers. In both cases, the right subclavian artery arose from the posterior wall of the aortic arch as its last branch, and ran rightwards between the esophagus and the vertebral column. The cases described belong to type G of the Adachi-Williams-Nakagawa-Takemura classification of aortic arch branching patterns.

View full abstract

Embryonic quail ovaries were examined with a scanning electron microscope. The same as in many bird species, the quail ovary degenerated on the right side, and normal development occurred only on the left side. The surface of the developing left ovary had a rough appearance. The epithelial cell surface was extremely swollen with many globular protrusions, and the cell borders were lined by ridge-like protrusions. On the other hand, the degenerating right ovarian surface was rather smooth in appearance. Each cell surface had a few short microvilli. Several stomata were found near the border between the ovary and mesonephros in the posterior region of the right ovary. The size and number of stomata were variable, but tended to increase in the later stages. These findings were compared with those in the chick ovary, and a discussion is included.

View full abstract

The aim of the present study is to evaluate the size and number of axons in the human spinal cord nerve fibers according to the aging process, and, after conducting morphometry of histology preparations at different ages, to show some of the effects of aging on those fibers. We examined thirty-eight human spinal cords which had been taken from cadaver specimens (25 males and 13 females) aged from 41 to 97 years. The spinal segments were embedded in celloidin and sections were stained with Luxol fast blue-periodic acid-Schiff-hematoxylin (LPH). Highly enlarged images with a square eyepiece grid and oil-immersion lens were used to count the myelinated axons and to measure the axon transverse area in a unit area of the posterior funiculus at C6 level, with the help of a microscope equipped with a drawing tube, an electronic optical planimeter and a computer. Significant age-related linear decreases were found for all parameters. Our report may provide new information concerning the aging process of the human spinal cord. It revealed that a decrease in size and number of axons were one of the important changes occurring with the aging process in the human spinal posterior funiculus.

View full abstract

The internal configuration of rat incisor odontoblasts was studied mainly by scanning electron microscopy (SEM) using the AODO method (low concentration aldehyde prefixation, osmium tetroxide postfixation, dimethyl sulfoxide (DMSO) freeze-fracture, osmium tetroxide maceration). The present SEM findings were compared with the results obtained by conventional transmission electron microscopy (TEM) of epon-embedded specimens. The following results were obtained: 1) Functioning odontoblasts were characterized by a concentric, laminar rough endoplasmic reticulum (rER) with many long mitochondria interposed.2) A network of tubular smooth endoplasmic reticulum (sER) was observed in the odontoblast process and distal portion of both functioning and resting odontoblasts.3) The tubulo-vesicular elements which have been found to present a modified Golgi-GERL organelle with secretory and absorptive functions were demonstrated in both the functioning and resting odontoblasts. Structurally they consist of the sER network and strings of granules and vesicles.4) Various types of cytoplasmic bodies, e. g., lysosomes, cytosomes and multivesicular bodies, related to the sER were also noted in both functioning and resting odontoblasts.5) Microapocrine secretion of membranous vesicles of varous sizes into the predentin and along the lateral branchings of odontobalst processes in the circumpulpal dentin was observed during the matrix apposition stage of the odontoblasts. The present morphological study revealed the threedimensional configuration of the intra- and extra-cellular structures related to dentinogenesis by odontoblasts.

View full abstract

Immunoreactivity to prolactin in the nervous system of the plerocercoid of Ligula intestinalis was demonstrated by immunocytochemical method. Numerous PRL immunoreactive perikarya with long varicose fibres were observed in the peripheral nervous system in the worm, mainly in the transversal muscle layer and medullary parenchyma of the midbody. A few fibres were found in the main nerve cords of the central nervous system. PRL positive neurons sent their processes to associate with the main nerve cords. The immunostaining terminals appeared in the subtegument region in the lateral border of the plerocercoid. The result indicates that PRL immunoreactivity is well-developed in the plerocercoid of the cestode. The significance of the localization of prolactin in the worm is discussed.

View full abstract