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The Novozym 435(R) catalyzed esterification and hydrolysis reactions of 4-methyloctanoic acid (ethyl ester) were investigated. In both the hydrolysis and esterification reactions, the increase of ethanol concentration led to an increase in enantiomeric ratio (E). For hydrolysis of the ethyl ester, the E-value increased from 5.5 [0% (v/v) EtOH] up to 12 [20% (v/v) EtOH]. In case of esterification, the E-value was already 16 [14% (v/v) EtOH] and rose to 57 [73% (v/v) EtOH]. When combining these results of esterification and hydrolysis, an enantiomeric ratio of 350 can be estimated for the sequential kinetic resolution of 4-methyloctanoic acid. In this way, enantiopure 4-methyloctanoic acid could be obtained after two consecutive reaction steps.

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The role of the hyaluronate receptor, CD44, is well known in adult mammal astrocytes where it modulates neuron-glia interactions. However, no data exist regarding its expression in other vertebrates during their development. In order to detect the expression of CD44 in the chicken and its possible involvement in glial precursor migratory patterns during spinal cord development, a monoclonal antibody (MoAb) against the mammalian standard isoform, CD44-H, was used in immunohistochemical and immunoblot assays. With these methods, CD44 hyaluronate receptors were found on mature astrocyte membranes of adult chicken spinal cord. Astrocytes were identified using a MoAb against GFAP. During development, small clusters of CD44 labelled cells were seen lining the central canal starting from embryonic stage E10. These labelled cells were dispersed in the dorsal, lateral and ventral funiculi of the spinal cord in the subsequent stages. After stage E15, the CD44 labelled cells were identified as astrocytes because of their GFAP immunoreactivity. We conclude that CD44 receptors on immature astrocyte precursors should be considered as early astrocyte markers which have a possible role during cell migratory dispersal.

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The neurofilament (NF) polypeptides of the fish giant Mauthner cell axons (MAs) and their degree of phosphorylation were investigated in the adult by means of immunoblot and immunohistochemical staining. Fasciculus longitudinalis medialis (FLM) axons of much smaller caliber, among which MAs run in the ventral spinal cord, were also analyzed in two teleost fish belonging to continuously growing species. To detect NF polypeptide subunits, commercially available monoclonal antibodies against mammalian NF-L (68 kDa), NF-M (160 kDa), phosphorylated (P) and non-phosphorylated (nP) NF-H (200 kDa) epitopes were used. These antibodies labelled bands of the identical molecular weight in fish cervical spinal cord total protein immunoblots. A peculiar NF composition of the MAs was observed, following immunohistochemical staining i.e. a low NF-M expression and a codistribution of P and (nP)-NF-H epitopes. Moreover, on the basis of immunoperoxidase staining in ultrathin longitudinal MA sections, we suggest that P NF-H are arranged in bundles, whilst (nP)-NF-H are likely to be free in the axoplasm. By contrast, FLM axons were found reactive with antibodies only against P NF-H. These results confirm that in carp and trout, NF have epitopes cross-reacting with monoclonal antibodies directed against the mammalian NF subunits. Furthermore, as regards the co-distribution of phosphorylated and non-phosphorylated NF-H epitopes in the M-cell axons, these might be considered as not yet completely mature axons taking into account that carp and trout belong to continuously growing species.

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The mouse monoclonal antibody anti-Leu-M1 (CD15) recognizes the carbohydrate determinant lacto-N-fucopentaose III, an oligosaccharide believed to be involved in cell-cell interactions. Anti-Leu-M1 is used in surgical pathology as an aid in the diagnosis of Hodgkin's disease. Additionally, adenocarcinomas derived from various organs stained positively with anti-Leu-M1 at the light microscopic level. Since mesotheliomas do not display positive reactivity to this antibody, Leu-M1 is clinically useful as part of a panel of antibodies in distinguishing adenocarcinomas from mesotheliomas. Previous work was carried out using post-embedding protein A-gold immunocytochemistry on thin sections embedded in Lowicryl K4M from a patient with Hodgkin's disease of the nodular sclerosing type; intense and precise labeling by gold particles was revealed in cytoplasmic granules, which were often clustered in a perinuclear location, in the Golgi apparatus, and focally along the plasma membrane of Reed-Sternberg cells. Moreover, polymorphonuclear leukocytes demonstrated similar labelling along the plasma membrane and over cytoplasmic granules. To define precisely the intracellular localization of Leu-M1 in human adenocarcinomas, we have performed post-embedding immunoelectron microscopy with the protein A-gold technique on sections embedded in Lowicryl K4M from neoplasms of the lung, stomach, colon, and breast. The pattern of labeling by gold particles indicative of Leu-M1 binding varied in adenocarcinomas of the different organs.

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