Tau Derived Hexapeptide AcPHF6 Promotes Beta-Amyloid (Aβ) Fibrillogenesis.

We studied the interactions of a tau derived hexapeptide AcPHF6 with β-amyloid peptides Aβ40 and Aβ42 which reveals its unusual ability to promote Aβ fibrillogenesis. The results demonstrate that the N-acetylated and C-amidated AcPHF6 hexapeptide can cause significant acceleration in Aβ40 and Aβ42 fibril growth. Aggregation kinetic studies at pH 7.

Synthesis and characterization of asymmetrical gemini surfactants.

The effect of variation in the length of surfactant hydrocarbon tail groups was tested in a series of dissymmetric gemini surfactants (N-alkyl N,N,N,N-tetramethyl-N-(6-pyren-6yl)-hexyl)propane-1,3-diammonium dibromide designated as CCCBr, with m = hexyl pyrene, and n = 8, 12, 14, 16, and 18. The aggregation properties of these surfactants have been investigated by means of H NMR, fluorescence spectroscopy, surface tension and electrical conductivity measurements. The critical micelle concentration (CMC) was determined using surface tension and confirmed using the specific conductance method.