Laminar organization of the main olfactory bulb of Podarcis hispanica: an electron microscopic and Golgi study

In this study, the lamination pattern of the main olfactory bulb (MOB) of P. hispanica has been described using EM and Golgi-impregnation techniques. Six layers could be distinguished from the external surface to the ventricles: olfactory nerve layer (ONL), glomerular layer (GL), external plexiform layer (EPL), mitral layer (ML), internal plexiform layer (IPL), and granular cell layer (GCL). In ONL unmyelinated axonic bundles from the olfactory mucosa are seen. The GL is defined by the presence of terminal ramifications of the mitral primary dendrites and by axonic terminals of the olfactory nerve. The EPL is a dendritic articulation layer between the mitral and granule cells, where a great density of dendrodendritic synaptic contacts has been found. The ML is defined by the large mitral cell somata, and the IPL by myelinated axonic bundles that run rostro-caudally. Finally, the GCL is characterized by the presence of granule cells. Using the Golgi-impregnation method, five different neuronal types have been described. In the glomerular layer, a small cell population is located; these neurons seem the periglomerular cells described in mammals. The second type corresponds to the mitral cell population and the morphological features of these cells resemble to those of mammals. The three remaining types constitute the granule cell population; this population is characterized by a great morphological heterogeneousness. However, these types have been differentiated according to their dendritic tree morphology and location of the cell body. A morphological gradient depending on the distance of cell body for each type to the ependymal layer, has been observed. In EM, four different types of neuronal cell bodies according to their location and ultrastructure have been defined. The laminar organization of the MOB of Podarcis is similar to that in all vertebrates. The results for the fine structure and dendritic tree morphology have revealed a high similarity between these reptiles and mammals.     

Spiral coils for arterial occlusion

Roentgen endovascular occlusion with spiral emboli was used in 240 patients with different diseases. The introduction of spiral emboli into the arteries of abdominal and retroperitoneal organs was fulfilled through usual angiographic catheters. Duration of the arterial occlusion was checked up in the following angiographic examinations and showed the devices described to be appropriate for a continuous arterial blockade. No complications resulting from the introduction of the spiral embolus were noted.     

Multiple regression analysis of twin data obtained from selected samples

The multiple regression analysis of twin data in which a cotwin's score is predicted from that of a proband (the member of a twin pair selected because of a deviant score) and the coefficient of relationship provides a powerful test of genetic etiology (DeFries and Fulker: Behav Genet 15:467-473, 1985). Moreover, when an augmented model containing an interaction term is fitted to the same data set, direct estimates of heritability (h2) and the proportion of variance owing to shared environmental influences (c2) are also obtained. In the present paper, the expected partial regression coefficients estimated from these models are derived, and the flexibility of the general approach is illustrated. An extended model is formulated for the analysis of data from combined samples of affected and control twin pairs that yields tests for differential h2 and c2 in the two groups as well as pooled estimates of these parameters. The application of these models is illustrated by an analysis of data from reading-disabled and control twin pairs. Because of the ease, flexibility, and utility of the multiple regression analysis of twin data, it is an appealing alternative to more traditional model-fitting approaches.     

Regulation of in vivo IgE biosynthesis in mice with complete Freund's adjuvant

Complete Freund's adjuvant (CFA) administered before sensitization dampened the normal and cyclophosphamide-enhanced response of high and moderate IgE responder phenotype mice (CAF1 and C57B1/6J, respectively). CFA-induced suppression of IgE biosynthesis was effective in reducing anaphylactic histamine release from approximately 2,900 ng histamine per milliliter to background levels (less than 100 ng/ml). CFA-induced ascites fluid was able to reduce the cyclophosphamide-enhanced IgE response of low-responder phenotype SJL mice from 1:320 to less than 1:5 as determined by passive cutaneous anaphylaxis. Muramyl dipeptide, a mycobacterial cell wall component capable of eliciting effects similar to those seen with CFA, was shown to induce suppression of IgE production if incorporated in incomplete Freund's adjuvant. Muramyl dipeptide administered in saline was ineffective, while incomplete Freund's adjuvant alone had some immunoregulatory properties. Ongoing IgE responses were less susceptible to regulation. CFA administered to sensitized C57B1/6J mice was ineffective in inducing IgE suppression when animals were challenged with antigen.     

Nuclear magnetic resonance proton imaging of bone pathology

Thirty-two patients with diversified pathology were examined with a supraconductive NMR imager using spin echo with different TR and TE to obtain T1 and T2 weighted images. They included 20 tumors (12 primary, eight metastasis), six osteomyelitis, three fractures, two osteonecrosis, and one diffuse metabolic (Gaucher) disease. In all cases except for the stress fractures, the bone pathology was clearly visualized in spite of the normal lack of signal from the compact cortical bone. Nuclear magnetic resonance (NMR) imaging proved to be at least as sensitive as radionuclide scintigraphy but much more accurate than all other imaging procedures including computed tomography (CT) and angiography to assess the extension of the lesions, especially in tumors extended to soft tissue. This is due both to easy acquisition of sagittal and coronal sections and to different patterns of pathologic modifications of T1 and T2 which are beginning to be defined. It is hoped that more experience in clinical use of these patterns will help to discriminate between tumor extension and soft-tissue edema. We conclude that while radionuclide scintigraphy will probably remain the most sensitive and easy to perform screening test for bone pathology, NMR imaging, among noninvasive diagnostic procedures, appears to be at least as specific as CT. In addition, where the extension of the lesions is concerned, NMR imaging is much more informative than CT. In pathology of the spine, the easy visualization of the spinal cord should decrease the need for myelography.