Amyloid-β (Aβ) self-assembly into cross-β amyloidfibrils is implicated in a causative role in Alzheimer’s disease pathology.Uncertainties persist regarding the mechanisms of amyloid self assembly and the role of metastable prefibrillar aggregates. Aβ fibrilsfeature a sheet-turn-sheet motif in the constituent β-strands; as such, turn nucleation has been proposed as a rate-limiting step in the se...

Long chain cis-prenyltransferase in rat liver microsomes was studied using various allylic isoprenoid substrates. Microsomes could utilize trans-geranyl pyrophosphate, but not cis-geranyl pyrophosphate for polyprenyl pyrophosphate synthesis. Both trans, trans-farnesyl pyrophosphate and trans,cis-farnesyl pyrophosphate were used as substrates with Km values of 24 and 5 microM, respectively. tran...

ultrafiltration (uf) was used for decolorization of an industrial iranian date syrup. experimental results were obtained by using two different concentrations of the date syrup (40 and 50 °brix) and two different membrane pore sizes (15-20 and 30-50 kda molecular weight cut-off values) under different trans-membrane pressures (tmp: 40, 70, 110 and 150 psi). the membrane with a pore size of 15-2...