TY - CHAP A1 - Deger, H. A1 - Reusch, Wolfgang A1 - Luchner, K. T1 - Microscopic Observation of Crystal Growth and Phase Transitions N2 - No abstract available Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33001 ER - TY - JOUR A1 - Tiu, W. U. A1 - Davern, K. M. A1 - Garcia, E. G. A1 - Moll, Heidrun A1 - Mitchell, Graham F. T1 - Monoclonal antibodies reacting with Schistosoma japonicum eggs and their target epitopes N2 - Ten monoclonal antibodies (McAbs) raised to Schistosoma japonicum eggs could be assigned using several serological and immunochemical techniques to 3 groups. The McAbs, termed A, B and C-McAbs, apparently recognize carbohydrate epitopes that can be located on the same antigen molecule. The antibodies, generally of IgM isotype, are idiotypically related. They are distinct from another IgM McAb (Group D-McAb) the carbohydrate target epitope of which can also be associated with the epitopes of A. B and C-McAbs. The McAbs produce large vacuolated bleb reactions in the circumoval precipitin test (COPT) and target epitopes have different representations in various life cycle stages such as immature and mature eggs, male and female worms (including S. mansoni). Antigens affinity purified on columns containing A, B, C and D-McAbs stimulate proliferation of T cells from egg-sensitized mice and elicit DTH reactions in such mice. This raises the possibility that the target antigens of these carbohydrate-reactive monoclonal antibodies are immunopathologic and involved in egg-induced granuloma formation. KW - Schistosoma japonicum; Egg antigen; Carbohydrate epitope; Circumoval precipitin test; Immunoassay Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30916 ER - TY - JOUR A1 - Solbach, W. A1 - Bogdan, C. A1 - Moll, Heidrun A1 - Lohoff, M. A1 - Röllinghoff, M. T1 - Parasitäre Evasionsmechanismen: Beispiel Leishmanien T1 - Mechanisms of Parasite Evasion: Leishmania as an Example N2 - Leishmanien besitzen eine Vielzahl von Mechanismen, die humorale und zelluläre Immunabwehr effektiv zu unterlaufen. Diese hängen eng mit der Expression von hauptsächlich zwei Glykokonjugaten auf der Parasitenoberfläche zusammen, dem gp63 und dem Lipophosphoglykan. Die Parasiten sind einerseits schlechte Aktivatoren des alternativen Komplementweges und umgehen damit ihre eigene extrazelluläre Lyse. Oberflächengebundene Komplementfaktoren fördern andererseits die Aufnahme der Leishmanien durch Makrophagen. Solange diese nicht durch T-Zellen aktiviert sind, dienen sie den Parasiten als "Refugium". Dies gilt insbesondere, als Leishmanien in der Lage sind, 1. den "oxidative burst" zu hemmen; 2. toxische Sauerstoffmetaboliten zu entgiften; 3. abbauende lysosomale Enzyme zu hemmen und 4. das saure Milieu in den Lysosomen für ihren eigenen Metabolismus auszunutzen. Schließlich unterlaufen Leishmanien die zelluläre Immunabwehr des Wirts, indem sie die Aktivierung von T-Lymphozyten hemmen und die Expansion von T-Zell-Sub-populationen bewirken, die für ihr eigenes Überleben nützlich sind. N2 - Leishmania display a variety of mechanisms for effective evasion of the humoral and cellular immune responses of the host which are strongly associ-ated with the expression of two major surface glycoconjugates, gp63 and lipophosphoglycan. The parasites are poor activators of the alternative com-plement pathway thus avoiding their own extracellular lysis. Complement bound on the surface of promastigotes promotes the uptake of leishmania by macrophages which function as »safe targets« as long as they are not acti-vated by T lymphocytes. This is due to the fact that intracellular parasites are able to 1. decrease the oxidative burst; 2. scavenge toxic oxygen metabolites; 3. inhibit degradative lysosomal enzymes; 4. exploit the acidic milieu of lysosomes for their own metabolism. Finally, leishmania have been shown to evade the host's cellular immune response by down-regulating T cell-activat-ing processes and by initiating the expansion of T cell subpopulations which promote their own survival. KW - Leishmanien KW - Immunsystem KW - Evasionsmechanismen KW - Makrophagen KW - T-Zellen KW - leishmania KW - immune System KW - evasion mechanisms KW - macrophages KW - T cells Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30920 ER - TY - JOUR A1 - Borasio, Gian Domenico A1 - John, Jacob A1 - Wittinghofer, Alfred A1 - Barde, Yves-Alain A1 - Sendtner, Michael A1 - Heumann, Rolf T1 - ras p21 protein promotes survival and fiber outgrowth of cultured embryonic neurons N2 - Although evidence obtained with the PC12 cell line has suggested a role for the ras oncogene proteins in the signal transduction of nerve growth factor-mediated fiber outgrowth, little is known about the signal transduction mechanisms involved in the neuronal response to neurotrophic factors in nontransformed cells. We report here that the oncogene protein T24-ras, when introduced into the cytoplasm of freshly dissociated chick embryonic neurons, promotes the in vitro survival and neurite outgrowth of nerve growth factor-responsive dorsal rootganglion neurons, brain-derived neurotrophic factor-responsive nodose ganglion neurons, and ciliary neuronotrophic factor-responsive ciliary ganglion neurons. The proto-oncogene product c-Ha-ras also promotes neuronal survival, albeit less strongly. No effect could be observed with truncated counterparts of T24-ras and c-Ha-ras lacking the 23 C-terminal amino acids including the membrane-an-choring, palmityl-accepting cysteine. These results sug-gest a generalized involvement of ras or ras-like proteins in the intracellular signal transduction pathway for neurotrophic factors. Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32621 ER - TY - CHAP A1 - Hodgson, Barbara A1 - Reusch, Wolfgang A1 - Kjöllerström, Bengt A1 - Velarde, Manuel T1 - Non-Formal Education N2 - No abstract available Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30620 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Tollervey, David T1 - Cloning of Schizosaccharomyces pombe genes encoding the U1,U2,U3 and U4 snRNAs N2 - No abstract available Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29919 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Ribes, V. A1 - Tollervey, David T1 - Schizosaccharomyces pombe U4 small nuclear RNA closely resembles vertebrate U4 and is required for growth N2 - No abstract available Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29771 ER -