Jason B. Lloyd

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During recent years N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers have been developed as targetable drug carriers. These soluble synthetic polymers are internalized by cells by pinocytosis and they can be tailor-made to include peptidyl side-chains degradable intracellularly by specific lysosomal enzymes. Thus they provide the opportunity fo achieve(More)
A method is described for the in vitro culture of 17.5-day rat visceral yolk sac. Tissue survival was good as judged by light and electron microscopy. The rate of pinocytic uptake of 125I-labeled polyvinylpyrrolidone by the tissue was constant both within and between experiments. Within the concentration range 0.15-24 mug/ml, the 125I-labeled(More)
N-(2-Hydroxypropyl)methacrylamide copolymers bearing oligopeptide side-chains terminating in p-nitroaniline (NAp) were incubated with rat liver lysosomal enzymes in the presence of the thiol glutathione, and the rate of p-nitroaniline release was measured. Twelve of the 16 side-chains investigated were hydrolysed to release p-nitroaniline and in all but one(More)
Pinocytic uptake of 125I-labeled bovine serum albumin by 17.5-day rat visceral yolk sac cultured in vitro has been examined. Uptake was followed by intracellular digestion and, after an initial period, the content of radioactivity in the tissue itself remained constant during the incubation. Radiolabel was returned to the culture medium predominantly as(More)
DBA2 mice were inoculated i.p. with 10(5)L1210 cells. Animals subsequently treated with daunomycin (single i.p. dose, 0.25-5.0 mg kg-1) all died. The maximum increase in mean survival time observed was approximately 135%. Animals treated with N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers conjugated to daunomycin (DNM) showed a significant increase in(More)
1. Previous studies have indicated that the permeability of polyethyleneglycol across the human intestine is anomalously high in comparison with the permeability of sugars with similar molecular mass. In consequence it has been proposed that two or more distinct mechanisms must exist for the translocation of these classes of molecule or, alternatively, that(More)
SUMMARY Conceptuses from 9-5-day pregnant rats have been cultured for 48 h in heat-inactivated homologous serum. Embryonic development was normal. The protein contents of embryos and visceral yolk sacs after different periods of culture were recorded. When m I-labelled polyvinylpyrrolidone or [ 3 H]dextran were added to the culture serum, radioactivity was(More)
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