Bulletin de l'Association des anatomistes最新文献

Purified mitochondria from rat brain were incubated in vitro which microtubule-associated proteins (MAPs) that are known to bind specifically on sites present on the outer membrane. The bound molecules were detected by immunoelectron microscopy and the linear distribution of the label along mitochondrial profiles was analyzed by statistical methods. The results demonstrate that gold-conjugated antibodies are distributed in a non-random fashion on the surface of mitochondria, suggesting regional concentrations of MAPs-binding sites. This finding argue for the existence of specialized domains on mitochondria that are involved in the association of the organelles to microtubules in situ.

The administration of 2250 IU of retinyl palmitate in young chick blastoderm at 4-5 HH stage brings 28% of surviving embryos and 84.5% malformed. The most frequent induced anomalies affect neural tube and/or neural crest which are the most sensible structures to vitamin A teratogenic action. The teratogenic mechanism would be produced by direct effect upon neuroblast and neural crest cells, and thus, this would cause the usual association of neural tube closure defects with facial malformations.

Bone grafts are becoming increasingly common in orthopaedics, neurosurgery and periodontology. Twenty one New Zealand rabbits were used in the present study comparing several materials usable as bone substitutes. A 4.5 mm hole was drilled in the inner femoral condyles. Holes were filled with either an autograft (from the opposite condyle), an hydroxylapatite (Bioapatite), or a highly purified bovine xenograft (T650 Lubboc). Animals were sacrificed at 1, 3 and 6 months post implantation and a quantitative analysis of newly-formed bone volume (BNF/IV) and remaining biomaterials (BMAT/IV) was done. In addition, some holes were left unfilled and served as controls. At 6 months, there was no tendency for spontaneous repair in the control animals. The autografted animals have repaired their trabecular mass and architecture within the first month. Hydroxylapatite appeared unresorbed at six months and only thin and scanty new trabeculae were observed. The xenograft induced woven bone trabeculae formation on the first month. This was associated with resorption of the material by two multinucleated cell populations. At six months, the epiphyseal architecture was restored and the biomaterial has disappeared in most cases. Xenografts appear a promising alternative to autografts and allografts, whose infectious risks and ethical problems should always be borne in mind.

Muscle biopsies were taken at the oesophageal opening and in the costal part of the diaphragm from 15 foetuses (aged between 11 and 40 weeks) and from four children aged 1 week, 5 months, 3 and 16 years. Subjects with multiple congenital abnormalities or neuromuscular diseases were not included in this study. Enzyme histochemistry (myosin ATPases) and immunohistochemistry using antibodies directed against vimentin, desmin, titin and different isoforms of the myosin heavy chains (MHCs) were carried out on serial frozen sections. The diameters of the different types of fibres were measured using a Leitz ASM 68K and the corresponding results were expressed either as mean values or as histograms. In both of the regions of the diaphragm which were examined (oesophageal opening and costal portion). The skeletal muscle fibres are formed from two successive generations in a manner very similar to that which we have previously described for the limb muscles. The chronology of the various events involved in the maturation of the diaphragm does however present certain distinctive features since the adult MHCs are expressed well before 30 weeks even though paradoxically large amounts of fetal MHC were still present at birth. These findings suggest the existence of a special regulatory mechanism in the diaphragm resulting either from its innervation by the phrenic nerve or from its specific functional constraints.

UV light fluorescent tracers (True Blue and Fast Blue) are placed in contact with sensitive receptors after dermabrasion. The abraded surfaces are limited to two hemidorsal areas and two hemi plantar areas on the animals' foot. A five days survival is allowed to enable the axonal retrograde transport of the tracers, then the animals are sacrificed and perfused with an intracardiac injection of 10% formaldehyde in phosphate buffer at 7.4 pH. The lumbar spinal ganglions are immediately dissected out, examined as a whole with a Leitz Dialux fluorescence microscope, then frozen and cut with a cryotome. The results of this analysis show that: i-only ipsilateral dorsal root ganglions are labeled by blue dye. ii-the number of fluorescent cells varies between 20 to 60 per ganglion. iii-a map of the distribution of the dermatomes on the rat hind foot can be deducted from the study of the labelled ganglions. They spread from L2 to L5 from the cranial to the caudal part, and from the medial to the lateral side of the rat foot, on both dorsal and plantar areas.

Cornea is only innervated by free nerve endings. A corneal scarification exposes free nerve endings which are able to transport True Blue and Fast Blue dyes by retrograde axonal transport. These tracers label the perikaryon. A few days later, the rats are sacrificed and perfused with an intra cardiac 10% formaldehyde perfusion in a phosphate buffer. The analysis of ipsilateral semi lunar (trigeminal) ganglion with a Leitz Dialux fluorescence Microscope shows fluorescent blue cells. The organization of these cells in the volume of the ganglion has been determined by selective labelling of each corneotopic zone in the supero-internal quarter of the rat trigeminal ganglion. Data from the literature about the somatotopic organisation of the other parts of the rat face are in agreement with these results.

The frondiformis ligament is a part of the retinaculum extensorum of the instep. Actuated by the tendons of the extensor digitorum longus, it takes a direct effect on the talus and the calcaneum, induces the valgus of the tarsus and contributes to the stability of the ankle and the foot.

Computed tomography using transversal scanning, may be usefull in the determination of liver volume. The aim of this study is to evaluate this technique in living subjects and to determine a relationship between liver volume and morphological body surface area and other morphological criteria. In a series of 25 patients, liver volume was computed from the body surface area, using a mathematical function. This method allow a quick and accurate determination of the liver volume which could be used in liver transplantation for a better matching between donor liver and recipient.