This report continues or examination of the effect of genetically engineered charge modifications on the partitioning behavior of proteins in aqueous two-phase extration. The genetic modifications consisted of the fusion of charged peptide tails to beta-galactosidase and charge-change point mutations to T4 lysozyme. Our previous article examined the influence of these charge modifications on pa...

A dextran sulphate gel column removed anti-double-stranded DNA antibodies (antidsDNA) selectively, efficiently, and safely from the circulation of a patient with systemic lupus erythematosus (SLE). The mechanism of the removal is thought to be due to cross reactivity of anti-dsDNA with dextran sulphate, which has negatively charged units. Selective removal of antidsDNA is expected to contribute...

A tissue culture virus isolation procedure for rabies street strain virus on mouse neuroblastoma cells is described. Parameters for the optimum sensitivity of the procedure were determined to include a minimum 4-day incubation of virus in tissue culture and the use of diethylaminoethyl-dextran for increased cell susceptibility. The in vitro procedure performed well in a comparison with the fluo...

Coxiella burnetii, the agent of Q fever, is an obligate intracellular bacterium that multiples within vacuoles of phagolysosomal origin. Persistently infected cell lines were maintained in continuous culture for months. We studied the pH of the phagolysosomes by using two murine cell lines during early propagation of the bacteria and after establishment of persistent infection. Three strains of...

Natural killer cells assess target cell health via interactions at the immune synapse (IS) that facilitates signal integration and directed secretion. Here we test whether the IS also functions as a gasket. Quantitative fluorescence microscopy of nanometer-scale dextrans within synapses formed by various effector-target cell conjugates reveal that molecules are excluded in a size-dependent mann...

Dextran hydrolysis-mediated conversion of polyethylene glycol (PEG)-dextran (DEX) aqueous two-phase system droplets to a single phase was used to directly visualize Dextranase activity. DEX droplets were formed either by manual micropipetting or within a continuous PEG phase by computer controlled actuation of an orifice connecting rounded channels formed by backside diffused light lithography....

p R E L I M I N A R Y work at this laboratory indicated that lambs are born with a low plasma vitamin A level. Similar results have been reported by Pierce (1947) and Pope et al. (1949). In the preliminary study a correlation of 0.39 was found between plasma vitamin A level of lambs at birth and birth weight, of 0.38 between plasma vitamin A level of lambs at 10 days and average daily gain from...

Partial Feed simulating moving bed (SMB) has proved to be more efficient in binary separation performance (purity, recovery, productivity) because of its two additional degrees of freedom, namely feed length and feed time, as compared to classical SMB process. The binary separation of dextran T6 and fructose with linear isotherm is modeled with Aspen Chromatography simulator in a four zone SMB ...

Perfusion studies of the anterior segment of the eye frequently involve an exchange of the contents of the anterior chamber. We here determined how much fluid was necessary to pass through the upstream tubing and anterior chamber such that the contents of the anterior chamber were adequately exchanged. We used fluorescein dextran (500 kD) to assess the adequacy of exchange of enucleated porcine...

Comparison of the effects of plasma exchange using lipoprotein-deficient plasma with those of LDL apheresis using a dextran sulphate column was undertaken in two groups of Watanabe heritable hyperlipidemic rabbits pre-labelled with 3H-cholesterol. Total and HDL cholesterol were reduced more by plasma exchange but HDL cholesterol rebounded higher after LDL apheresis; rises in HDL cholesterol cor...