[Platelet Adhesion Assay (PADA), a new quantitative test for assessment of platelet function and therapeutic drug monitoring of GPIIb/IIIa and ADP receptor antagonists]. / PADA, der neue Plättchenadhäsionstest: Quantitative Messung der Plättchenfunktion und therapeutisches Monitoring von Glykoprotein-IIb/IIIa- und ADP-Rezeptorantagonisten.

Platelet ADhesion Assay (PADA) is a POCT capable method for quantitative determination of platelet adhesiveness. Using special polymer particles and test conditions adjusted to the physiologic conditions, the current functional state of blood platelets is determined directly from a whole blood sample. Within a short time, using little technical equipment and small sample volume, a therapeutic drug monitoring of GP IIb/IIIa and ADP receptor antagonists is possible, too. Whereas in healthy volunteers dose/effect curves of GP IIb/IIIa antagonists vary only slightly, in thrombopilic patients there are big variations. Differences in efficacy up to drug resistance may occur also in use of the ADP receptor antagonist clopidogrel. A therapeutic drug monitoring of GP IIb/IIIa- and ADP receptor antagonist therapy is essential and becomes feasible using PADA, also as long-term drug monitoring of ADP receptor antagonists and detection of drug resistance. Additionally, an individual ex vivo dose estimation for GP IIb/IIIa antagonists is possible. PADA allows diagnostics of pathological platelet function in thrombophilic patients as well as long-term therapeutic drug monitoring due to its simple handling.

Riboflavin, overproduced during sporulation of Ashbya gossypii, protects its hyaline spores against ultraviolet light.

Riboflavin (vitamin B2), essential in tiny amounts as a precursor for oxidoreductase coenzymes, is a yellow pigment. Although it causes cytotoxicity via photoinduced damage of macromolecules, several microorganisms are striking overproducers. A question, unanswered for decades, is whether riboflavin overproducers can benefit from this property. Here, we report an ultraviolet (UV) protective effect of riboflavin. The spores of Ashbya gossypii, a riboflavin-overproducing fungus, are more sensitive to UV than those of Aspergillus nidulans. The addition of riboflavin to suspensions improves the UV resistance of both spore types. Interestingly, we show that regulation of sporulation and riboflavin overproduction in A. gossypii are linked. In batch culture, both were elevated when growth ceased. At constant growth rates, obtained in a chemostat culture, neither was elevated. Supplementation of cultures by cAMP, a known stress signal, negatively affected sporulation as well as riboflavin overproduction, establishing a second, independent argument for the linkage.