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The Atlantic-Mediterranean exchange of water at Gibraltar represents a significant heat and freshwater sink for the North Atlantic and is a major control on the heat, salt and freshwater budgets of the Mediterranean Sea. Consequently, an understanding of the response of the exchange system to external changes is vital to a full comprehension of the hydrographic responses in both ocean basins. Here, we use a synthesis of empirical (oxygen isotope, planktonic foraminiferal assemblage) and modeling (analytical and general circulation) approaches to investigate the response of the Gibraltar Exchange system to Atlantic freshening during Heinrich Stadials (HSs). HSs display relatively flat W-E surface hydrographic gradients more comparable to the Late Holocene than the Last Glacial Maximum. This is significant, as it implies a similar state of surface circulation during these periods and a different state during the Last Glacial Maximum. During HS1, the gradient may have collapsed altogether, implying very strong water column stratification and a single thermal and delta O-18(water) condition in surface water extending from southern Portugal to the eastern Alboran Sea. Together, these observations imply that inflow of Atlantic water into the Mediterranean was significantly increased during HS periods compared to background glacial conditions. Modeling efforts confirm that this is a predictable consequence of freshening North Atlantic surface water with iceberg meltwater and indicate that the enhanced exchange condition would last until the cessation of anomalous freshwater supply into to the northern North Atlantic. The close coupling of dynamics at Gibraltar Exchange with the Atlantic freshwater system provides an explanation for observations of increased Mediterranean Outflow activity during HS periods and also during the last deglaciation. This coupling is also significant to global ocean dynamics, as it causes density enhancement of the Atlantic water column via the Gibraltar Exchange to be inversely related to North Atlantic surface salinity. Consequently, Mediterranean enhancement of the Atlantic Meridional Overturning Circulation will be greatest when the overturning itself is at its weakest, a potentially critical negative feedback to Atlantic buoyancy change during times of ice sheet collapse.

The surface water hydrography along the western Iberian margin, as part of the North Atlantic's eastern boundary upwelling system, consists of a complex, seasonally variable system of equatorward and poleward surface and subsurface currents and seasonal upwelling. Not much information exists to ascertain if the modern current and productivity patterns subsisted under glacial climate conditions, such as during marine isotope stage (MIS) 2, and how North Atlantic meltwater events, especially Heinrich events, affected them. To help answer these questions we are combining stable isotope records of surface to subsurface dwelling planktonic foraminifer species with sea surface temperature and export productivity data for four cores distributed along the western and southwestern Iberian margin (MD95-2040, MD95-2041, MD99-2336, and MD99-2339). The records reveals that with the exception of the Heinrich events and Greenland Stadial (GS) 4 hydrographic conditions along the western Iberian margin were not much different from the present. During the Last Glacial Maximum (LGM), subtropical surface and subsurface waters penetrated poleward to at least 40.6 degrees N (site MD95-2040). Export productivity was, in general, high on the western margin during the LGM and low in the central Gulf of Cadiz, in agreement with the modern situation. During the Heinrich events and GS 4, on the other hand, productivity was high in the Gulf of Cadiz and suppressed in the upwelling regions along the western margin where a strong halocline inhibited upwelling. Heinrich event 1 had the strongest impact on the hydrography and productivity off Iberia and was the only period when subarctic surface waters were recorded in the central Gulf of Cadiz. South of Lisbon (39 degrees N), the impact of the other Heinrich events was diminished, and not all of them led to a significant cooling in the surface waters. Thus, climatic impacts of Heinrich events highly varied with latitude and the prevailing hydrographic conditions in this region.

SummaryBlocking the cofactor function of human tissue factor may be beneficial in various coagulation-mediated diseases. The murine antibody D3 binds to the membrane proximal substrate interaction region of human tissue factor and blocks tissue factor function even in the presence of bound factor VIIa. The cloned murine D3 antibody was humanized and affinity matured by exchanging amino acids in the complementarity determining regions as well as in the antibody framework. The humanized antibody, D3H44, bound to tissue factor with a 100-fold increased affinity (KD 0.1 nM) as compared to the original murine and chimeric versions. Depending on the particular disease, different pharmacokinetic properties of the antibody may be required and, therefore, several antibody variants – F(ab), F(ab’)2, IgG2, IgG4 and IgG4b – were generated. In vitro, the humanized D3 antibodies displayed potent inhibition of plasma clotting and tissue factor: factor VIIa-mediated activation of factors IX and X (e. g. D3H44-F(ab’)2, IC50 (F.X) 47 pM). In addition, D3H44-F(ab’)2 completely prevented fibrin deposition in a human ex vivo thrombosis model under venous blood flow conditions (IC50 37 nM). The humanized D3 antibodies may be utilized for treatment of cardiovascular diseases which involve tissue factor activity, e. g. acute coronary syndrome and venous thrombosis.

Vom Strand des Ostseebades Timmendorferstrand in der Lubecker Bucht wurden 40 Sandproben mit Hilfe der Haarkodermethode nach Vanbreuseghem auf keratinverwertende Pilze, insbesondere auf pathogene Dermatophyten untersucht. Vergleichsweise wurden auch zehn Erdproben aus strandnahen Garten, sowie zehn Meerwasserproben mituntersucht. Eine Reihe von Sandproben war mykologisch vollig negativ, die andern enthielten lediglich Sporen von Trichophyton terrestre, einem keratin verwertenden, bislang als apathogen geltenden Bodensaprophyten, der bei fluchtiger Untersuchung mit Trichophyton mentagrophytes verwechselt werden kann. Drei Sandproben enthielten auserdem den Schimmelpilz Cephalosporium acremonium, der in seltenen Fallen als pathogen angesehen wurde. Andere Dermatophyten wurden im Sand nicht gefunden. Die Gartenerde war in samtlichen Fallen Trichophyton terrestrehaltig, acht der zehn Proben ergaben auserdem ein uppiges Wachstum von Keratinomyces ajelloi den Haarkodern entlang. Das Meerwasser erwies sich als mykologisch negativ. Da zahlreiche Perithecien von Trichophyton terrestre nachgewiesen wurden, wird fur die perfekte Form dieses Pilzes die Bezeichnung Ctenomyces terrestris, fur die imperfekte Form die Beibehaltung von Trichophyton terrestre angeregt.