Citations

Experimental rhinovirus infection in volunteers has provided important new knowledge on the pathogenesis and treatment of rhinovirus colds. However, the clinical parameters of this illness have not been well defined. In the current study, data on 151 young adult subjects in 14 previous studies were used to determine representative values for nasal mucus weights and total and nasal symptom scores for the rhinovirus challenge model. The mean ± SD total mucus weight for 5 days was 22.6 g ± 22.2 and the mean total symptom score was 16.4 ± 12.7. By univariate analysis, the 5-day total mucus weight correlated with the 5-day score for rhinorrhea, nasal obstruction, and total symptoms, but by multivariate analysis the correlation was primarily with rhinorrhea. Similar findings were seen using daily mean values. The information obtained from this analysis will be useful in planning and interpreting the results of future experiments using the rhinovirus model.

Abstract Von Willebrand pigs have all the manifestations of the severe human disease. The role of Willebrand antigen (VIII R:AG) and ristocetin cofactor (VIII: RWF) was assessed in these pigs by (1) transfusion and (2) ’in vitro' bleeding time assay. The skin bleeding time became normal when the level of transfused Willebrand factor (VIII R: AG/RWF) was raised in the plasma above 30 U/dl. After single or repeated transfusions, skin capillary endothelium and platelets were still distinguished from normal by VIII R:AG deficiency. When incisions in excised porcine skin (’in vitro' bleeding time) were perfused with blood and plasma fractions, haemostasis occurred when plasmatic Willebrand factor exceeded 30 U/dl whether the skin or platelets came from normal or from von Willebrand pigs. The platelet plug occluding the skin incision contained VIII R:AG by immunofluorescence. Willebrand factor appears to coat surfaces and to serve as a platelet attachment protein. These bleeder pigs are resistant to atherosclerosis. If platelets are involved in early atheroscolerotic lesions, the role of Willebrand factor in platelet - blood vessel interaction may be important.