Platelet GPIIb supports initial pulmonary retention but inhibits subsequent proliferation of melanoma cells during hematogenic metastasis

Platelets modulate the process of cancer metastasis. However, current knowledge on the direct interaction of platelets and tumor cells is mostly based on findings obtained in vitro. We addressed the role of the platelet fibrinogen receptor glycoprotein IIb (integrin alpha IIb) for experimental melanoma metastasis in vivo. Highly metastatic B16-D5 melanoma cells were injected intravenously into GPIIb-deficient (GPIIb(-/-)) or wildtype (WT) mice. Acute accumulation of tumor cells in the pulmonary vasculature was assessed in real-time by confocal videofluorescence microscopy. Arrest of tumor cells was dramatically reduced in GPIIb(-/-) mice as compared to WT. Importantly, we found that mainly multicellular aggregates accumulated in the pulmonary circulation of WT, instead B16-D5 aggregates were significantly smaller in GPIIb(-/-) mice. While pulmonary arrest of melanoma was clearly dependent on GPIIb in this early phase of metastasis, we also addressed tumor progression 10 days after injection. Inversely, and unexpectedly, we found that melanoma metastasis was now increased in GPIIb(-/-) mice. In contrast, GPIIb did not regulate local melanoma proliferation in a subcutaneous tumor model. Our data suggest that the platelet fibrinogen receptor has a differential role in the modulation of hematogenic melanoma metastasis. While platelets clearly support early steps in pulmonary metastasis via GPIIb-dependent formation of platelet-tumor-aggregates, at a later stage its absence is associated with an accelerated development of melanoma metastases

Entwicklung eines Verfahrens zur in situ-Datenauswertung bei geoelektrischen Widerstandsmessungen fuer die mineralische Rohstoffsuche

Copy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Entwicklung eines Verfahrens zur in situ-Datenauswertung bei geoelektrischen Widerstandsmessungen fuer die mineralische Rohstoffsuche Abschlussbericht

TIB: FR 386 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Quasi-chemical viscosity model for fully liquid slag in the Al2O3-CaO-MgO-SiO2 system. Part II: evaluation of slag viscosities

A model is presented that enables viscosities to be predicted reliably over the whole range of compositions and temperatures in the AlO -CaO-MgO-SiO slag system above liquidus in the temperature range from 1543 K to 2643 K (1270°C to 2370°C). Experimental procedures and data from the studies reported in the literature have been collected and critically reviewed with particular attention to the viscometry methods and possible contamination of slag samples to select reliable data points for further model development. Relevant revised formalism to describe the complex viscosity trends including charge-compensation effect of the Ca and Mg cations on the formation of tetrahedrally coordinated Al was introduced. Parameters of the quasi-chemical viscosity model have been optimized to reproduce within experimental uncertainties most of the selected experimental data in the AlO -CaO-MgO-SiO system and all subsystems. This study is part of the overall development of the self-consistent viscosity model of the AlO-CaO-FeO-FeO- MgO-Na O-SiO multicomponent slag system

Review of experimental data and modeling of the viscosities of fully liquid slags in the Al2O3-CaO-'FeO'-SiO2 system

A general model based on the Urbain formalism has been developed, which enables the viscosities of liquid slags to be predicted for all compositions in the Al2O3-CaO-'FeO'-SiO2 system in equilibrium with metallic iron. Available experimental viscosity data have been analyzed and critically reviewed. The Urbain formalism has been modified to include compositional dependent model parameters. Experimental data in unaries, binaries, ternaries, and the quaternary system have been described by the model over the whole compositional and temperature ranges using one set of model parameters. This viscosity model can now be applied to various industrial slag systems