Four guanidine derivatives of N4,N9-diacylated spermine have been designed, synthesized, and characterized. These guanidine-containing cationic lipids bound siRNA and formed nanoparticles. Two cationic lipids with C18 unsaturated chains, N1,N12-diamidino-N4,N9-dioleoylspermine and N1,N12-diamidino-N4-linoleoyl-N9-oleoylspermine, were more efficient in terms of GFP expression reduction compared ...

A large series of publications 1-9 has proposed that cationic peptides from leukocytes kill bacteria primarily by causing a depolarization of their membranes leading to enhanced permeability. One group of cationic peptides from human neutrophils was even coined bacteri-cidal/permeability-increasing proteins. 3 Surprisingly, however, none of a large series of other publications that had proposed...

Activated DNA-directed DNA synthesis catalyzed by Rauscher leukemia virus (RLV) and other type C mammalian retroviral DNA polymerases is uniquely stimulated by biologically active polyamines. Cationic trypanocides may act as antagonists of polyamine function. As described here, several cationic trypanocides stimulate RLV polymerase-catalyzed DNA-directed DNA synthesis at concentrations signific...

The synthesis and evaluation of a new class of cationic iodinated contrast agents for the imaging of cartilage using computed tomography (CT) are described. In direct comparisons with anionic contrast agents, the cationic contrast agents afforded higher equilibrium concentrations in the articular cartilage of ex vivo rabbit femurs and thus greater imaging sensitivity. Variations in CT intensity...

The effect of polyelectrolytes; cationic and anionic charges and coagulants have been investigated for fresh activated sludge at different concentrations and pH values in a comparative fashion. The results from the experiments indicate that the cationic polyelectrolytes have a significant effluence on the sludge characteristic, degree of flocculation and water quality such as turbidity and SVI....

Aspartate aminotransferase (L-aspartate: 2-oxoglutarate aminotransferase, EC 2.6.1.1, glutamic-oxalacetic transaminase, GOT) comprises two isoenzymes. One is anionic and is associated principally with the soluble fraction of the cytoplasm, the other is cationic and is associated with the mitochondria [4]. A sensitive semi quantitative assay has been developed for cationic aspartate aminotransfe...

In this report, the synthesis of a novel class of cationic quaternary ammonium-surface-functionalized silicon nanocrystals (ncSi) using a novel and highly versatile terminal alkyl halide-surface-functionalized ncSi synthon is described. The distinctive features of these cationic ncSi include colloidal stability, pH-independent positive surface charge, and size-tunable photoluminescence (PL) in ...

Critical micelle concentrations (CMCs) of cationic surfactant (alkyltrimethylammonium bromides, CnTABr, where n = 10, 12, 14, 16 and 18), and a bile salt sodium cholate (NaC) were determined from surface tension, conductance and dye solubilization methods, while of their equimolar mixtures from surface tension and dye solubilization methods. The interaction parameter (beta) obtained from analys...