[Is it allowed to have a public open exhibition of human plastinated specimens in Japan?].

This survey was conducted to know what inhibits the public open exhibitions of human anatomical specimens. Questionnaires were handed to 1,035 visitors to the public open exhibition of plastinated specimens at the University of Tokyo between March 30 and April 4, 1995. Five hundred and twenty-two responses were analyzed. The survey revealed following responses of medial and non-medical visitors. 1) Over 90 percent of the visitors welcomed to the public open exhibition of human anatomical specimens. 2) Visitors concerned about the aim of the exhibition and hoped explanations of exhibited specimens. They thought it is necessary to pay attention to the privacy of the cadavers and their families. 3) The most impressive specimens to the visitors were whole body silicone specimens and a series of slices of a whole body for both medical and non-medical visitors. 4) Medical visitors evaluated specimens high for medical education to understand three dimensional structures. On the contrary, non-medical visitors are astonished to encounter the whole body specimens not the dissected ones, and found the identity and human beings in the specimens. 5) Some anatomists strongly stand against the public open exhibitions of anatomical specimens because the plastinated specimens are quite different from ordinary hormaline fixed specimens and they expect that non-medical people must get upset about the specimens.

Setting up and features of a database of images of plastinated materials.

A database of plastinated materials was set up and distributed with a CD-ROM on the Internet. A total of 197 specimens, prepared at the Medical Museum of the University of Tokyo between 1991 and 1995, were catalogued in the database on a personal computer with commercial and original software. The database was originally designed to catalogue anatomical specimens and drawings for curators and researchers, but it also services as a worldwide digital museum.

Architectural design, fiber-type composition, and innervation of the rat rectus abdominis muscle.

The rectus abdominis muscle is architecturally compartmentalized by tendinous intersections and is supplied by multiple thoracic nerves. In this study, the rectus abdominis of the rat has been qualitatively and quantitatively examined with regard to muscle dimensions, fiber organization, fiber-type composition, and innervation. The muscle exhibits architectural heterogeneity and different patterns of innervation among its thoracic, epigastric, and hypogastric parts. The epigastric part, adherent to the rectus sheath via tendinous intersections, represents relatively simple design. It is formed by serially arranged compartments with shorter fibers, compared with the other parts. These compartments are segmentally supplied by thoracic nerves. The hypogastric part is more complex, forms an interdigitation of muscular slips, and has segmental distribution of thoracic nerves in mediolateral direction. The thoracic part much differs from the other parts. It has smaller cross-sectional areas, compartments composed of abundant nonspanning fibers with intrafascicular termination, and non-segmental distribution of thoracic nerves. In addition to these craniocaudal specializations among the three parts, the muscle exhibits mediolateral differences in fiber-type composition. Slow-twitch oxidative fibers are more densely distributed in the medial half region than the lateral, whereas fast-twitch glycolytic fibers follow an inverse pattern. The mediolateral differences in fiber-type composition as well as the craniocaudal specializations in architectural design and innervation imply regionally differentiated recruitments of the muscle in various behaviors.

Lower axial skeleton of the musk shrew (Suncus murinus).

Macroscopic structure as well as pre- and postnatal development of the lumbar, sacral, and caudal vertebrae of the musk shrew (Suncus murinus, Insectivora) were observed. The lumbar vertebrae possess two pairs of unusual processes, hyperapophyses and hypapophyses. The hyperapophyses are located on the dorsal surface of the caudal articular processes of all the lumbar vertebrae, whereas the hypapophyses are found on the caudal part of the ventral surface of the bodies in the first few lumbar vertebrae. The former gives attachment to the Mm. rotatores lumborum and the latter to the Mm. psoas major and minor. The articular processes of the lumbar vertebrae are oriented more horizontally compared with those in other mammals. The sacrum is very narrow transversely due to poor development of the ventrolateral wing. The auricular surface includes cranial parts of the wing and of the fused vertebral arches as well as the cranial articular process of the first sacral vertebra. In the caudal vertebrae, chevron bones are H-shaped when viewed ventrally, and give attachment to tendons of the caudal muscles. This report describes the relationships between the structural peculiarities of the lower axial skeleton and the locomotive habits of the musk shrew.

Central distribution of the stapedius motoneurons in the rat--a study of topographical anatomy and HRP transport experiments.

A detailed anatomical description of the stapedius muscle area in the rat was given and on this basis the central distribution of the neurons innervating the stapedius muscle was investigated by the horseradish peroxidase transport method. The stapedius muscle showed a circum-pennate structure with a para-centrally located tendon and was composed of about 500 muscle fibers. It contained no special sensory structures and was innervated by a single branch of the facial nerve consisting of myelinated axons. Horseradish peroxidase experiments provided the following findings. The stapedius muscle received few sensory components. The stapedius motoneurons resided in the brainstem ipsilaterally in a column-like region ventromedial to the facial motor nucleus. Some of them (up to 6%) were scattered rostrally as far as the level of the facial nerve exit. Almost all the stapedius motoneurons showed fusiform morphology with significantly smaller mean diameter and lesser size variation than the facial nucleus motoneurons. The number of the stapedius motoneurons per animal on one side amounted about 150 which was about the same as that of axons in the stapedius nerve. Their axons except for those of rostrally scattered ones shared the intramedullary route with axons of the facial nucleus motoneurons.

An introduction to Anatomical Image Digitizing System (AIDS).

We designed, constructed, and evaluated a prototype of a digital data management system for anatomical studies and education, named AIDS (Anatomical Image Digitizing System). By implementing the prototype systems, we intended to determine the technical and anatomical parameters required for such a system, and to attempt digital imaging analysis of morphology. We demonstrated that such systems can be used as a new morphological tool on a macroscopic level, particularly in mathematical image analysis, in comparative anatomy by organizing a database and by modifying images with graphic techniques, and in statistical discussions by manipulating large numbers of illustrations quickly. A 512 X 512 X 8 bit matrix is judged to be satisfactory for analyzing images mathematically and producing illustrations of bones, but higher quality tools are required to store anatomical figures with halftones in a good condition, and to prepare fine anatomical illustrations. Classifications of figures and formats of figure legends are necessary to standardize the storage of figures in the form of a database.

Acute hepatotoxicity induced by hepatotoxins in Suncus murinus.

A comparative study was conducted to contrast the hepatotoxicity of several chemicals in the musk shrew (Suncus murinus) versus other common laboratory species (mouse or rat), and the following results were obtained from serum enzymes (SGOT and SGPT) and histopathological findings of liver specimens. The sensitivity of Suncus liver to CCl4 was different from that of mouse liver. The sensitivity of Suncus liver to beta-D-galactosamine was weaker than that of rat liver. The sensitivity of Suncus liver to ethanol was stronger than that of mouse liver. After a single oral administration of ethanol (99.5% v/v, 0.1 ml/50 g body weight), the gallbladder of Suncus became enlarged and dark blue in color. A striking fatty degeneration was seen 24 h after a single ip administration of amethopterin at 50 mg/kg in Suncus liver.

Anatomy and histology of the musk shrew (Suncus murinus) prostate.

Gross anatomy and the light and electron microscopic characteristics of the musk shrew (Suncus murinus, Insectivora) prostate are described. The prostate is a pair of compound tubuloalveolar glands with one main excretory duct for each gland. Each gland is divided into ventral and dorsal lobes. The tubuloalveoli are larger in diameter and the secretory cells are lower in the ventral than in the dorsal lobes. Probable spontaneous release of secretory granules and accumulation of secretory material in secretory lumina are only observed in the ventral lobes. Secretory material is often crystallized in the secretory lumina. The epithelium of excretory ducts consists of mucous-type secretory cells and the boundary between this epithelium and the glandular epithelium is complex. The glandular epithelium consists of secretory and clear cells. This report illustrates that the structure of the prostate of musk shrew is unique among mammals.

The characterization of 2,3-alkanediol diacyl esters obtained from the Harderian glands of Mongolian gerbil (Meriones unguiculatus).

A major lipid class in the Harderian glands of the Mongolian gerbil was investigated. The IR and 1H-NMR spectra suggested that it was a wax-like compound. Fatty acids present were capric, lauric, myristic, palmitic, stearic, arachidic, and behenic acids in ratios of 3.0%, 16.3%, 16.5%, 29.5%, 5.1%, 16.4%, and 9.8%, respectively. Odd-numbered, branched chain and unsaturated fatty acids were not present in large amounts. The structure of the alcohol moiety was elucidated to be 2,3-alkanediol with carbon chain lengths from C12 to C22 by GC-MS of the TMS and isopropylidine derivatives. Lemieux-von Rudloff oxidation of these alcohols confirmed the 2,3-diol structure, giving fatty acids two carbon units shorter.

A histological study of the Harderian gland of Mongolian gerbils, Meriones meridianus.

The histological structure of the gerbil Harderian gland was investigated by means of light and transmission electron microscopy. The single excretory duct of the gland is directly continuous with endpieces at the hilus and opens nasally and ventrally to the third eyelid. The excretory duct is accompanied by many acini of small serous glands around it. The gland is composed of tubuloalveoli (tubular alveoli) with wide lumina and is not divided into lobules. There is no branched duct system within the gland. The tubuloalveoli themselves convey the secretory materials to the hilus where the excretory duct begins. The alveolar epithelium is composed of only one type of glandular cell as well as myoepithelial cells. The glandular cells contain many clear secretory vacuoles containing lipids and well-developed tubular smooth endoplasmic reticulum. The secretory vacuoles are surrounded by a unit membrane and are secreted by exocytosis. The interstices of the gland contain two types of autonomic nerve varicosities and a number of melanocytes. The surface of the gland is covered with the endothelium of the orbital venous sinus.

Subdivision of mouse vibrissae on an embryological basis, with descriptions of variations in the number and arrangement of sinus hairs and cortical barrels in BALB/c (nu/+; nude, nu/nu) and hairless (hr/hr) strains.

Development of vibrissae was studied in dd/y mouse embryos by scanning electron microscopy. Arrangement of vibrissae and cortical barrels were also studied by light microscopy in adult dd/y, BALB/c(nu/+), nude (BALB/c, nu/nu) and hairless (hr/hr) mice to find genetic or epigenetic variations. Rudiments of vibrissae first appear on Day 12 of pregnancy as longitudinal ridges on the developing muzzle, and each hair rudiment is represented by a dome on the ridges. The dorsal two rows (A and B; Woolsey and Van der Loos, '70) of mystacial vibrissae are on the lateral nasal prominence, while the ventral three (C, D and E) are on the maxillary prominence. Smaller hairs of mystacial vibrissae appear at the labial part of the maxillary prominenceon Day 13. The rudiments of rhinal hairs also appear at this stage on the part of the muzzle derived from the medial nasal prominence. Thus the so-called mystacial vibrissae should be subdivided into three (or 4, including the rhinal) groups on an embryological basis. They are the lateral nasal, the maxillary and the labial. A supernumerary sinus hair and a corresponding barrel was observed between D and C rows uni-or bilaterally in one third of individuals of BALB/c, nude and hairless mice. It is suggested that supernumerary hairs tend to occur between the groups of hairs as defined above. In nude and hairless mice small barrels representing labial hairs are diminished in number. The number of hair follicles, however, is normal.

Arrangement and structure of sinus hair muscles in the big-clawed shrew, Sorex unguiculatus.

The arrangement and structure of sinus hair muscles in the snout of the shrew, Sorex unguiculatus, were studied by electron microscopy and serial section light microscopy. Both striated and smooth muscles are directly associated with sinus hair follicles. The striated muscle fibers originate from the base of a follicle and insert onto the superficial portion of adjoining caudally positioned follicles. Some fibers insert into the corium instead of inserting into a follicle. The fibers show a fine structure typical of red fibers. Smooth muscle cells form a network with elastic fibers beneath the corium. Some cells are directly attached to the capsule of the sinus, thus forming a type of M. arrector pili. Striated muscle febers that appear to end in the corium are connected with the smooth muscle network through the elastic fibers which appear to function as the tendon of these two types of muscle cell.

Structure of the sinus hair follicle in the big-clawed shrew, Sorex unguiculatus.

The structural features of sinus hair follicles in Sorex unguiculatus were studied by macroscopic dissection, serial section light microscopy and electron microscopy. The shrew has about 540 sinus hairs regularly arranged on the snout. The maxillary nerves innervating them are extremely thick, while the optic nerves are very thin. Thus the follicle must be one of the most important sense organs in this animal. In the follicle the ring sinus is well-development and the trabeculae of the cavernous sinus are reduced in number and thickness. The ring bulge is not a unified structure but a pair of bodies which consist of head, stalk and attachment plaque. It is characterized by the presence of numerous thick collagen fibrils (400 nm) and appears to be mechanically rigid. Lanceolate nerve terminals, free endings, Merkel cells with nerve terminals and unmyelinated fibers are observed, but encapsulated endings are lacking in and aound the follicles. Straight lanceolate terminals on the posterior side of the follicle are thick and three-sided in cross section, while those on the anterior side are thin and two-sided. Free endings are located on the anterior side of the follicle. These and other findings are discussed on the basis of the assumption that the Sorex sinus hair follicle is more specialized as a vibrating system than in other mammals.

Population and structure of nerve cells in mouse submandibular ganglion.

The anatomy of the mouse submandibular ganglion, and population and fine structure of nerve cells were studied by light and electron microscopy. The submandibular ganglion is a plexus containing up to forty ganglia along the main and the smaller excretory ducts of the submandibular gland. Measurements of the volume of nerve cell bodies display a pattern of distribution with two main peaks, suggesting the presence of large and small types of the intraganglionic neuron. The large neurons mainly have axo-dendritic synapses in which the postsynaptic element is a small spine-like process, while axo-somatic synapses are more common in the small neurons. In some small neurons nuclear chromatin is unusually conspicuous, and accumulations of vesicles of fairly uniform size occur within the cell body. Decentralized ganglia contain almost no synapses showing the absence of definite interneurons.