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Experimental evidence suggests that carbohydrates and their corresponding receptors (endogenous lectins) decode biological information. Therefore, the expression of complex oligosaccharides--the potential ligand part of this recognition system--during chondrogenesis and osteogenesis was determined in the viscerocranium of fetal rats by mapping the staining patterns of exogenous lectins. Results were compared with the expression of bone- and/or cartilage-specific core proteins and the binding profiles of neoglycoconjugates. These synthetic tools make possible the localization of sugar-ligand-binding sites. The spatial and temporal distribution patterns of glycoconjugates were highly dynamic and demonstrated a clear correlation with characteristic morphological modifications. The glycobiological characterization of precartilage mesenchymal cells revealed distinct differences compared to prospective bone anlagen. Especially the binding of the exogenous lectin from Griffonia simplicifolia II, that selectively visualized prechondral aggregations, reveals that regulation of early chondral growth is at least phenomenologically correlated with a relatively atypical oligosaccharide composition terminating with N-acetylglucosamine.

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Alterations in the expression of glycoconjugate structures during cartilage development in the chondrocranium, nasal skeleton, Meckel's cartilage, limb buds, vertebral bodies and ribs were investigated comparatively in 13 to 21-d-old rat embryos. The binding patterns of 24 biotinylated lectins were analysed in serial sections and compared with results obtained using histochemical methods. Proteoglycan distribution, assessed by conventional staining procedures, was not associated with lectin binding sites. During early fetal development, hyaluronate concentrations were enhanced in areas of prospective chondrogenesis. With few exceptions, the lectins showed a general increase in intensity of binding to mesenchymal structures. Con A (Canavalia ensiformis), DSL (Datura stramonium), and WGA (Triticum vulgare) displayed a ubiquitous distribution of binding sites. After incubation with LCA (Lens culinaris), PSA (Pisum sativum), STL (Solanum tuberosum), and VAA (Viscum album), characteristic differences in binding intensity between focal areas of developing mesenchyme were seen. DBA (Dolichus biflorus), ECL (Erythrina cristagalli), GSL I (Griffonia simplicifolia), LTA (Lotus tetragonobolus), SJA (Saphora japonica), UEA I (Ulex europaeus) and VVL (Vicia villosa) consistently failed to bind. During chondrogenesis a general reduction of lectin staining was detected. In early stages of development GSL II (Griffonia simplicifolia) was a specific marker of the prechondral blastema in the viscerocranium. PNA (Arachis hypogaea) selectively labelled the prevertebral blastema. In contrast, condensing mesenchyme of limb buds and viscerocranium was not stained. Using RCA (Ricinus communis), it was possible to distinguish chondroblasts from mature cells. All chondrocytes were stained by PSA, PHA-E, PHA-L (Phaseolus vulgaris E and L), and WGA, whereas Con A, LCA, and GSL II detected distinct differences between cartilage with different localisations. Cartilage matrix was constantly negative. Applying GSL II it was possible to distinguish specific segments of the perichondrium. From our results we conclude that especially high mannose oligosaccharides are amplified during development. Terminal sialic acid molecules, branched intralaminar glucose and/or mannose, respectively, internal galactose-(beta 1,4)-N-acetylglucosamine sequences as well as galactose-(beta 1,3)-N-acetylgalactosamine sequences in a preterminal position are diffusely distributed in mesenchymal tissue. In contrast, no evidence for the presence of terminal GlcNAc(beta 1,4)GlcNAc sequences and terminal alpha-fucosyl residues in (1,2) or (1,3)-linkage was obtained. Chondrogenesis appears to be correlated with a general reduction in the extent of expression of oligosaccharide structures. No proof of terminal N-acetylgalactosamine and alpha-galactose moieties was found, whereas our staining results document the expression of terminal beta-galactose structures in restricted areas of the developing mesenchyme.(ABSTRACT TRUNCATED AT 400 WORDS)

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The staining patterns of 24 biotinylated lectins were analyzed in serial sections of the mandible of 13- to 21-day-old rat embryos by means of the avidin-biotin-peroxidase method. A ubiquitous distribution of binding sites was demonstrated after incubation with Con A (Canavalia ensiformis), DSL (Datura stramonium; except bone matrix), and WGA (Triticum vulgare). ECL (Erythrina cristagalli), GSL I (Griffonia simplicifolia), SJA (Saphora japonica), VVL (Vicia villosa), DBA (Dolichus biflorus), UEA I (Ulex europeus), and LTA (Lotus tetragonobolus) were constantly negative. In early stages of development, GSL II (Griffonia simplicifolia II) was a selective marker of prechondral blastema. In contrast, PNA (Arachis hypogaea) did not stain condensing mesenchyme. During chondrogenesis of Meckels's cartilage a general decrease of lectin binding was observed. Mature cartilage matrix was constantly negative. Chondrocytes were marked by the lectins PSA (Pisum sativum), WGA, PHA-E, and PHA-L (Phaseolus vulgaris E and L). A strong GSL II binding was restricted to the mesial-superior region of the perichondrium. In later stages, several lectins revealed significant differences between preskeletal ("central") areas and the remaining ("peripheral") mesenchyme. A clear binding reaction was noted in central regions by applying LEA (Lycopersicon esculentum) and STL (Solanum tuberosum), while the peripheral tissue was only faintly stained. Developing bone was specifically marked by succinylated WGA (sWGA). The lectins LCA (Lens culinaris) and RCA (Ricinus communis) bound to fibers and extracellular matrix of the connective tissue. Jacalin (Artocarpus integrifolia) and SBA (Glycine max) binding sites were found in macrophages. Affinity of VAA (Viscum album) increased parallel with maturation of endothelial cells. Specific lectin-binding patterns revealed no correlation with the distribution of glycosaminoglycans. The results demonstrate a general reduction of oligosaccharide structures during development of Meckel's cartilage. From our observations we conclude that intralaminar glucose and/or mannose sequences as well as terminal sialic acid molecules are ubiquitously distributed, while terminal alpha-fucose was constantly negative. Lectin-binding patterns of macrophages may reflect the presence of specifically linked terminal galactose. Our findings indicate that oligosaccharides terminating in N-acetylglucosamine are bone-specific. The significance of the restricted staining of the perichondrium by GSL II remains to be elucidated.

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The distribution of endogenous lectins, visualized by labelled neoglycoproteins, and of defined oligosaccharide structures, reactive with plant lectins, during fetal development of the fingers was analyzed in sections of human 3- to 8-month-old fetal specimens. Chondrogenesis as well as ossification were correlated with characteristic modulations in the expression of both glycoligand-binding molecules and characteristic carbohydrate structures. Occurrence of xylose-specific receptors was judged to be an early sign of cartilage development. Similarly, alpha-mannosyl residues that had been attached to labelled carrier proteins were strongly bound by the extracellular matrix already during early stages of finger maturation. Staining intensity for heparin gradually increased during chondrogenesis, whereas affinity for mannose showed a stage-related decline. Binding of mannose-6-phosphate was confined to hypertrophied cartilage of primary ossification centers. Accessible binding sites for terminal N-acetylneuraminic acid and N-acetylgalactosamine moieties were detected only in osteoid. In addition to monitoring the sugar-binding capacity, presence and developmental regulation of distinct carbohydrate structures were also assessed. PSA and SBA enabled the demonstration of an abrupt loss of staining affinity in the zone of maturing hypertrophic cartilage. Succinylated WGA proved to be an apparently useful marker of evolving bone tissue. GSL-II binding was restricted to chondroclasts and osteoclasts. The findings of this investigation are consistent with the supposed role of glycoconjugate-lectin interactions in cartilage and bone development.

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The distribution of complex carbohydrate structures during the embryonic development of the rat palate was analysed by examining lectin-binding patterns in serial paraffin and cryostat sections. With few exceptions, the binding patterns showed a general increase in lectin receptors in the more developed stages of palatogenesis. High mannose oligosaccharides were especially amplified during development. Terminal fucose molecules were not expressed. In contrast, terminal sialic acid molecules were ubiquitously distributed in epithelial and mesenchymal tissues. Non-sialylated terminal N-acetylglucosamine was specifically restricted to evolving bone matrix. Before palatal fusion, quantitative but not qualitative differences were detected between oral, nasal, and medial-edge epithelial surfaces. The only exception was LCA, which specifically marked epithelial cells at the tip of palatal shelves. A very selective affinity for Jacalin was demonstrated in the oral epithelium of the palate after day 16, suggesting the presence of sialylated terminal galactose-(beta-1,3)-N-acetylgalactosamine. PNA specifically marked the basal lamina of the oral side of palatal processes. The binding patterns of DBA, GSL IA, SBA, and VVA indicated that the epithelium of the tongue is characterized by terminal alpha- and beta-galactose residues, whereas palatine cells possess only molecules with beta-anomery. During palatogenesis, glycosaminoglycans patterns were significantly modified. Our data suggest that alteration of complex carbohydrate structures may play a central role in modulating cell-cell and cell-matrix interactions. The significance of these findings, however, remains to be elucidated.

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The aim of this study was to monitor accelographically the impact of atracurium (A) and/or vecuronium (V) on intubation anaesthesia in infants and/or children for elective surgery or minor short-term surgery. An intra-individual evaluation is valid even though a very practical but less established monitoring method is used. Infants receiving a "priming"-dose of V 0.01 mg kg-1 BW or A 0.05 mg kg-1 BW followed 3 minutes later by a main dose of V 0.04 mg kg-1 BW or A 0.2 mg kg-1 BW were found to be in good or even very good intubation condition. These minimal doses afforded very short relaxation times, which are next in line to succinylcholin. A combination of V and A in the "priming"-technique did not lead to better conditions of any clinical relevance. Medium range non-depolarising muscle blockers, as they are available to the pediatric anesthetist nowadays, seem to compare favourable with the use of succinylcholin, which is to be considered an obsolete drug due to its various side effects.

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Efflux of choline from the rat cerebral cortex in vivo was investigated using the cup technique. After removal of the dura mater, the cup was placed on the cortex. Transmission and scanning electron microscopy revealed that the cortex was separated from the cup solution (100-300 microliter) by basal lamina, pia mater, arachnoid (with discrete defects) and remainders of the subdural neurothelium. Two kinds of experiments were carried out to determine: efflux of unlabelled choline into the cup solution; and translocation of radioactivity from the plasma into the cup solution (via blood-brain barrier and leptomeningeal layers) during i.v. infusion of [3H]choline or [14C]inulin. The former process was highly temperature-sensitive in contrast to the latter. Penicillin-G-sodium, which is known to damage the blood-brain barrier, was added to the cup solution, enhanced efflux of unlabelled choline, and caused a 5-fold increase in the rates of translocation of radioactivity during infusion of either labelled choline or inulin. In contrast, physostigmine (3 X 10(-4) M, added to cup solution) failed to enhance 3H-translocation, but markedly facilitated the efflux of unlabelled choline; this effect was highly temperature-sensitive and was blocked by atropine. It is concluded that activation of muscarinic receptors enhanced the choline efflux from cortical tissue. This effect was caused by cellular mobilization of choline presumably through an action on the metabolism of phosphatidylcholine. The effect was not due to alterations in the translocation of choline from the plasma to the cup solution, i.e. through permeability changes in the blood-brain barrier and in the leptomeningeal 'barrier'.(ABSTRACT TRUNCATED AT 250 WORDS)

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The aim of this study was to investigate the frequency of the different possibilities of the origin of the right gastric artery. The most frequent origin of the A. gastrica dextra was the A. hepatica propria (ca. 53%). Often the artery arised from the region where the A. hepatica communis divides into its branches (ca. 20%) or from the left hepatic branch (ca. 15%). In some cases (ca. 8%) it occurred as a branch of the A. gastroduodenalis and only in ca. 4% it arised from the A. hepatica communis. The findings concerning the frequency of the origin from the A. hepatica propria and from the A. hepatica communis are in accordance with the results obtained by some other authors. The observations concerning the frequency of the origin from some other arterial vessels (gastroduodenal artery, left and right hepatic branches and some other little branches) vary widely in the literature. As an incidental finding the observation of a truncus gastrolienalis and a truncus hepato- mesentericus has been made. Thereby the A. hepatica communis showed a flexuous course around the portal vein. In this connection the definition of the term "truncus hepato- mesentericus " is discussed.

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In 2 cats nerves of the spinal pia mater were studied by means of electron microscopy. These nerves possessed no perineurium. However, it has been observed that flat cells of the surrounding connective tissue can form an incomplete covering for small nerve bundles. In addition the perivascular nervous plexus of subarachnoid arteries of the brain stem, which were examined in 1 animal, also showed no perineural sheath. These results are discussed with those reported in the literature dealing with the perineurium of other peripheral nerves. The observations concerning the distribution and the composition of leptomeningeal nerves are in accordance with those obtained by light microscopic investigations.

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After intracisternal injection of heparinised autologous blood in cats, spinal nerve exits (SNE) of the subarachnoid space (SAS) were examined by scanning and transmission electron microscopy. Phagocytes, erythrocytes and erythrophages (= macrophages which had phagocytosed red blood cells) were found at SNE. Some lining cells of the SAS had retracted from the adjacent cells and had rounded up. Cells which formed an integral part of the subarachnoid lining cells also had phagocytosed erythrocytes. Debris of an exhausted erythrophage was phagocytosed by other macrophages. Finally the observation has been made that erythrophages are capable of leaving the SAS actively by migrating through the layer of lining cells, thus getting into the leptomeningeal connective tissue space.

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Pleocytosis in cerebrospinal fluid and infiltration of the leptomeningeal tissue have been studied after injection of ferritin into the subarachnoid space (SAS) of cats. The most important source of granulocytes in the leptomeninges are the relatively large veins of the pia mater, which have very thin walls. Passing between the lining cells of the pia mater the granulocytes leave the connective tissue space of the pia mater and reach the SAS. Leukodiapedesis has also been observed in veins crossing the SAS. During this process, gaps between the lining cells of the perivascular leptomeningeal sheath may develop. There are two possible ways for the granulocytes to pass from the vascular pia mater to the avascular arachnoidea: either they migrate actively on the surface of the leptomeningeal trabeculae or they reach the arachnoidea passively by the circulation of the cerebrospinal fluid. Leukodiapedesis in the vessels of the dura mater occurs relatively seldom and would not be able to cause the occasionally massive infiltration of the arachnoidea.

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We investigated the topography between small arteries and the proximal Vena saphena magna after observations and extractions of specimens made during variectomies. Moreover we studied this region by anatomical preparation. During an operation a small artery with transvenous course had been observed. The obtained specimen were examined histologically. The developmental mechanism of such an unusual course of an artery is discussed.

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The ventral attachement of the ligamentum vocale of eleven larynges (new-born and adults has been studied in sagittal, frontal and horizontal sections. 1. Supplementary to the known structure of the ventral attachement of the ligamentum vocale we have noticed collagen fibers which ascend in the inner angle of the thyroid cartilage and which partly cross to the other side. Sometimes a few fibers which are running downward have been observed. This structure of the attachement must be more firm than the known structure. 2. Moreover it has been observed that a lot of the angles of the crossing collagen fibers in the cartilage of the lamina mediana (near the attachement of the ligamentum vocale) are right-angled, whereas the angles of the fibers which lie in the laminae laterales in their majority are acute-angled. This phenomenon also is interpreted as a structure which makes the lamina mediana firmer. The fact, that this structure is not so evident in the specimens of the new-born as in those of the adults indicates that there are postnatal changes in the structure of the lamina mediana.

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The granula meningica of man (medium and advanced age) were investigated by means of light microscopy and scanning electron microscopy. We established the following: 1. The endothel of the sinus durae matris of man only seldom shows the blind tubes of endothel which were described by Andres (1967)1 after investigations made in cats and dogs. 2. a) There are no tube systems lined with mesothelial cells in the tissue of the granula meningica. Usually the cellcords and cellclusters are solid. Only in exceptional cases do they have a cavity. b) There are wide spaces between the collagen fibrebundles. These spaces are filled with a thinly liquid amorphous ground substance. We observed many free cells there (especially macrophages). 3. The construction of the connective tissue of the granula meningea lead us to conclude, that they are capable of changing their volume and shape considerably. The possible functional consequences of these results were discussed.

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1. After fixation with formalin or gluteraldehyd and OSO4 the cavum leptomeningeum of pig and cow has been investigated. The obtained specimen were dried in critical-point-method. 2. The results were quite congruente to the literature when we magnified the specimen with slight magnification. The trabeculas and membranes go to the Arachnoidea in a diverging way. Moreover we have found the following phenomena: 3. The mesothelium of the cavum leptomeningeum possesses microvilli and pored gaps. 4. The fragility of the mesothelium and the danger of producing artefacts in preparation has been observed.

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