The response of strain 2 guinea pigs to limiting doses of bovine serum albumin is under dominant genetic control linked with the poly-L-lysine gene. Inbred strains 2 and 13 guinea pigs make similar antibody responses to 10 mug bovine serum albumin, whereas strain 2 but not strain 13 animals produce significant amounts of antibodies in response to 0.1 mug. The relationship between the presence o...

Microencapsulation with hydrocolloids as a modern technique has been used to prolong the survival of probiotics during exposure to harsh conditions. In this study, alginate-Hylon starch microcapsules with genipin cross-linked chitosan and poly-L-lysine coatings were developed to encapsulate four strains of probiotic bacteria, including Lactobacillus casei (ATCC 39392), Bifidobacterium bifidum (...

Microencapsulation with hydrocolloids as a modern technique has been used to prolong the survival of probiotics during exposure to harsh conditions. In this study, alginate-Hylon starch microcapsules with genipin cross-linked chitosan and poly-L-lysine coatings were developed to encapsulate four strains of probiotic bacteria, including Lactobacillus casei (ATCC 39392), Bifidobacterium bifidum (...

Positively charged macromolecules cause a variety of pathological events through their electrostatic interaction with anionic sites present on the membrane of target cells. In the present study we have investigated the effect of hyaluronic acid, a negatively charged molecule, on rat paw oedema induced by poly-L-lysine as well as on histamine release from rat mast cells and nitric oxide formatio...

This paper reports on a novel application of an amphoteric water-soluble polyamidoamine named AGMA1 bearing 4-butylguanidine pendants. AGMA1 is an amphoteric, prevailingly cationic polyelectrolyte with isoelectric point of about 10. At pH 7.4 it is zwitterionic with an average of 0.55 excess positive charges per unit, notwithstanding it is highly biocompatible. In this work, it was found that A...

We report on the design and characterization of a class of biomolecular interfaces based on derivatized poly(l-lysine)-grafted poly(ethylene glycol) copolymers adsorbed on negatively charged surfaces. As a model system, we synthesized biotin-derivatized poly(l-lysine)-grafted poly(ethylene glycol) copolymers, PLL-g-[(PEGm)((1-x)) (PEG-biotin)(x)], where x varies from 0 to 1. Monolayers were pro...

Temperature- and pH-responsive dispersions of carbon nanotubes in water have been obtained by using di- and tri-block copolypeptides, in which the temperature responsive behaviour is provided by a poly(N-isopropylacrylamide) block, while the pH responsiveness is provided by two different polypeptides with an ampholytic behaviour, poly(L-glutamic acid) and poly(L-lysine). The molecular architect...

Detergent-permeabilized EGFR-T17 fibroblasts, which overexpress the human epidermal growth factor (EGF) receptor, phosphorylate both poly-L-(glutamic acid, tyrosine) and exogenous calmodulin in an EGF-stimulated manner. Phosphorylation of calmodulin requires the presence of cationic polypeptides, such as poly-L-(lysine) or histones, which exert a biphasic effect toward calmodulin phosphorylatio...