Expression of low-affinity Fc gamma receptor by a human metastatic melanoma line.

The class IIa of low-affinity receptors for the Fc region of IgG, Fc gamma RIIa, are expressed on immune cells. The cross-linking of Fc gamma RIIa by complexed IgG triggers activation of protein tyrosine kinase and internalization of immune complexes. In this report, we demonstrate the expression of Fc gamma RIIa by a human melanoma cell line (VIO) derived from a metastasis of a patient with regressive melanoma. The analysis of Fc gamma RIIa functions was performed in VIO cells and Fc gamma RlIa- or Fc gamma RIlb-transfected human melanoma cells (A375). The Fc gamma RIIa cross-linking induced protein tyrosine phosphorylation, including Fc gamma RIIa phosphorylation, and led to its internalization in a clathrin-independent way in human melanoma cells. Moreover, we showed that a part of internalized Fc gamma RIIa migrates in late endosomes, lysosomes and class II-containing compartments. These results suggest that melanoma cells can express functional Fc gamma RII, which might play a role in tumor-host relationships.

The role of morphological structure in the processing of compounds: the interface between linguistics and psycholinguistics.

This study presents a cross-linguistic investigation of lexical access and subjects' sensitivity to the internal morphological structure of compounds in two highly inflected languages, Greek and Polish. The following questions were addressed: Are individual constituents activated during on-line word recognition? To what extent does internal morphological structure play a role during lexical access? Is there an interaction between headedness and constituent-priming given that the inflection that the second constituent carries determines the gender, number, and case of the compound? Our results show activation of individual constituents of compounds during priming, a strong word effect, and a positional advantage for first constituents in spite of the presence of second constituent heads.

Surveillance and control of aflatoxins B1, B2, G1, G2, and M1 in foodstuffs in the Republic of Cyprus: 1992-1996.

Aflatoxins (AFs) B1, B2, G1, and G2 in locally produced and imported foodstuffs (nuts, cereals, oily seeds, pulses, etc.) were monitored and controlled systematically and effectively from 1992-1996. Samples (peanuts, pistachios, etc.) with total AFs above the Cyprus maximum level (ML) of 10 micrograms/kg fluctuated between 0.7 and 6.9%. The results indicate the effectiveness of monitoring, as well as the need for constant surveillance and control, especially at critical control points (sites of import, primary storage, etc.), to prevent unfit products from entering the Cyprus market. The control included sampling, retainment, analysis, and destruction of foodstuff lots with AF levels above MLs. The highest incidence of aflatoxin contamination was observed in peanut butter (56.7%) and the highest level of AF B1 was found in peanuts (700 micrograms/kg). Levels of AF M1 in raw and pasteurized milk analyzed in 1993, 1995, and 1996 were within both the Cyprus ML (0.5 microgram/L) and the lower ML (0.05 microgram/L) of some European countries. Only 12% of samples had detectable levels of AF M1. Analyses were performed by immunochemical methods. When recoveries were lower than 80%, the AF levels were corrected for recovery.