Untersuchungen zur Pollen- und Sporenflora des Bitterfelder Bernsteins - Erste Ergebnisse

Vorgestellt werden erste Ergebnisse palynologischer Untersuchungen an Bitterfelder Bernstein. Anhand von mindestens 18 Pollen- und Sporentypen „Höherer Pflanzen“ wird eine Rekonstruktion der Umweltbedingungen im Bernsteinwald vorgenommen. Erstmals konnte Nyssa (Tupelobaum) für den Bitterfelder Bernsteinwald nachgewiesen werden. Unter Berücksichtigung der stratigraphischen Reichweite einzelner Pollen- und Sporentypen wird versucht, das Bildungsalter der Bernsteine abzuleiten. Vermutlich datieren sie in das Bartonium bis Priabonium (SPP 17 bis SPP 18, ca. 41,3-33,9 Ma).First results of palynological investigations on Bitterfeld amber are presented. A reconstruction of the environmental conditions in the amber forest is carried out on the basis of at least 18 types of pollen and spores of "Higher plants". For the first time, Nyssa (Tupelo) could be detected as a species of Bitterfeld amber forest. Taking into account the stratigraphic range of individual pollen and spore types, an attempt is made to derive the age at which amber was formed. Bitterfeld amber presumably date from Bartonian to Priabonian (SPP 17 to SPP 18, ca. 41,3-33,9 Ma)

Vitamin D improves endothelial dysfunction and restores myeloid angiogenic cell function via reduced CXCL-10 expression in systemic lupus erythematosus.

Patients with systemic lupus erythematosus (SLE) have accelerated cardiovascular disease and dysfunctional endothelial repair mechanisms. Myeloid angiogenic cells (MACs), derived from circulating monocytes, augment vascular repair by paracrine secretion of pro-angiogenic factors. We observed that SLE MACs are dysfunctional and secrete pro-inflammatory cytokines. We also found that the vitamin D receptor was transiently expressed during MAC differentiation and that in vitro, calcitriol increased differentiation of monocytes into MACs in both SLE and in a model using the prototypic SLE cytokine, interferon-alpha. The active form of vitamin D (calcitriol) restored the SLE MAC phenotype towards that of healthy subjects with reduced IL-6 secretion, and normalised surface marker expression. Calcitriol also augmented the angiogenic capacity of MACs via the down-regulation of CXCL-10. In SLE patients treated with cholecalciferol for 12 weeks, the improvement in endothelial function correlated with increase in serum 25(OH)D concentrations independently of disease activity. We also show that MACs were able to positively modulate eNOS expression in human endothelial cells in vitro, an effect further enhanced by calcitriol treatment of SLE MACs. The results demonstrate that vitamin D can positively modify endothelial repair mechanisms and thus endothelial function in a population with significant cardiovascular risk

Table 1 : AMS-14C data used for the reconstruction of the Wismar Bay shoreline displacement curve

The Baltic coast of Mecklenburg-Vorpommern is located in the transition Zone between the region of Fennoscandian Uplift and the Central European Depression. In relation to the eustatic sea-level rise, the northeast coast shows a slower inundation, while for the southwestern area a faster transgression is indicated, which can be attributed to crustal movements. To determine the spatial and temporal differences since the onset of the Littorina Transgression, three relative sea-level curves have been established along a transect parallel to the gradient of upliftlsubsidence. The Wismar Bay area is one endpoint of the transect demonstrating today 10 Abb., 2 Tab. a relative sea-level rise of 1.4 mm/a. To determine the relative sea-level curve for the Wismar Bay, two sites were investigated on Rustwerder Spit (Poel) and Redentin. They provided reliable depth-age data, while the stratigraphy was additionally supported by lithological/geochemical, pollen, diatom and macrofossil data. Additional evidence was provided by archaeological submarine surveys and excavations. Comparing the new relative sea-level curve with a curve from the Vorpommern coast, it can be shown that for the period from 4000 cal BC until present, the differences between the two curves are caused by a constant neotectonic movement, while for the older periods an increasing isostatic component must be taken into account