TY - JOUR A1 - Dabauvalle, Marie-Christine A1 - Schulz, Barbara A1 - Scheer, Ulrich A1 - Peters, Reiner T1 - Inhibition of nuclear accumulation of karyophilic proteins in living cells by microinjection of the lectin wheat germ agglutinin N2 - No abstract available Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34288 ER - TY - JOUR A1 - Schulz, Erhard A1 - Joseph, Alain A1 - Baumhauer, Roland A1 - Schultze, Ekkerhard A1 - Sponholz, Barbara T1 - Upper Pleistocene and Holocene history of the Bilma region (Kawar, NE-Niger) T1 - Evolution de la region de Bilma (Kawar, NE-Niger) au Pleistocene superier et a l'Holocene N2 - A 42 m drilling was pertormed in the depresalon of Bilma, Xawar, NE-Niger. The sediment and pollen records show that after an initial deposition of dune sands there were repeated lake phases which terminated by desiccation and consolidation of spring mounds. The pollen record indicates a continuous presence of savanna vegetation. The record probably covers the period between the Upper Pleistocene and the Late Holocene. The climate was characterised by a monssonal summer rain regime giving effective rain fall of about 450-500 mm per year. Groundwater recharge was possible but estimates of the amount of water resources are difficult because of the karstic system of the escarpment and the nearly unknown hydrogeological situation. N2 - Dans la dépression de Bilma, Kawar, NE-Niger, un forage de 42 m a été réalisé. La séquence couvre la période entre le Pléistocene supérieur et l'Holocéne tardif. Apres une phase initiale de dépôts des sables dunaires, trois phases lacustres sont visibles, chaque fois terminées par une période de dessiccation et formation de dépôts de sources en buttes. Les invertigations polliniques montrent que, pendant toute la période, une végétation de savane était dominante. Le paléoclimat était caractérisé par un régime de mousson et des précipitations effectives d'environ 450-500 mm par an ainsi que des invasions de dépressions atlantiques. Une recharge de la nappe phréatique était possible, mais la connaissance insuffisante de l'hydrologéologie et du systeme karstique rend une estimation des ressources en eau tres difficile. KW - Pleistozän KW - Holozän KW - Bilma Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86828 ER - TY - JOUR A1 - Kleefeldt, Florian A1 - Upcin, Berin A1 - Bömmel, Heike A1 - Schulz, Christian A1 - Eckner, Georg A1 - Allmanritter, Jan A1 - Bauer, Jochen A1 - Braunger, Barbara A1 - Rueckschloss, Uwe A1 - Ergün, Süleyman T1 - Bone marrow-independent adventitial macrophage progenitor cells contribute to angiogenesis JF - Cell Death & Disease N2 - Pathological angiogenesis promotes tumor growth, metastasis, and atherosclerotic plaque rupture. Macrophages are key players in these processes. However, whether these macrophages differentiate from bone marrow-derived monocytes or from local vascular wall-resident stem and progenitor cells (VW-SCs) is an unresolved issue of angiogenesis. To answer this question, we analyzed vascular sprouting and alterations in aortic cell populations in mouse aortic ring assays (ARA). ARA culture leads to the generation of large numbers of macrophages, especially within the aortic adventitia. Using immunohistochemical fate-mapping and genetic in vivo-labeling approaches we show that 60% of these macrophages differentiate from bone marrow-independent Ly6c\(^{+}\)/Sca-1\(^{+}\) adventitial progenitor cells. Analysis of the NCX\(^{−/-}\) mouse model that genetically lacks embryonic circulation and yolk sac perfusion indicates that at least some of those progenitor cells arise yolk sac-independent. Macrophages represent the main source of VEGF in ARA that vice versa promotes the generation of additional macrophages thereby creating a pro-angiogenetic feedforward loop. Additionally, macrophage-derived VEGF activates CD34\(^{+}\) progenitor cells within the adventitial vasculogenic zone to differentiate into CD31\(^{+}\) endothelial cells. Consequently, depletion of macrophages and VEGFR2 antagonism drastically reduce vascular sprouting activity in ARA. In summary, we show that angiogenic activation induces differentiation of macrophages from bone marrow-derived as well as from bone marrow-independent VW-SCs. The latter ones are at least partially yolk sac-independent, too. Those VW-SC-derived macrophages critically contribute to angiogenesis, making them an attractive target to interfere with pathological angiogenesis in cancer and atherosclerosis as well as with regenerative angiogenesis in ischemic cardiovascular disorders. KW - macrophages KW - angiogenesis KW - bone marrow-derived monocytes Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-299724 VL - 13 IS - 3 ER -