Navigating α-Synuclein Aggregation Inhibition: Methods,Mechanisms, and Molecular Targets

Parkinson's disease is a yet incurable, age-related neurodegenerative disorder characterized by the aggregation of small neuronal protein α-synuclein into amyloid fibrils. Inhibition of this process is a prospective strategy for developing a disease-modifying treatment. We overview here small molecule, peptide, and protein inhibitors of α-synuclein fibrillization reported to date. Special attention was paid to the specificity of inhibitors and critical analysis of their action mechanisms. Namely, the importance of oxidation of polyphenols and cross-linking of α-synuclein into inhibitory dimers was highlighted. We also compared strategies of targeting monomeric, oligomeric, and fibrillar α-synuclein species, thoroughly discussed the strong and weak sides of different approaches to testing the inhibitors.     

On the flexibility of cyclochain polymers

Conformational parameters for a wide variety of aromatic cyclochain polymers have been computed assuming free rotation about virtual bonds. The flexibility with free rotation is shown to be determined by the geometry of the repeat unit and can vary over a wide range (15–1500 Å). Experimental values of the Kuhn segment length A are calculated from literature data on the hydrodynamic behavior of polymeric macromolecules of this class in solution. For most polymers A_fr for free rotation is equal to the experimental A_exp, and hindered rotation is mainly due to bulky substituents. © 1993 John Wiley & Sons, Inc.     

Influence of aluminum on the lipid composition of pond snails present in media with different acidities

It has been established that the toxic action of aluminum on the hydrobiontLymnaea stagnalis L. increases in an acid medium. The dual action of acidification and a toxicant lowers the survival rate. The lipid and phospholipid compositions of pond snails of control and experimental groups at various concentrations of toxicant and various pH values of the water have been investigated.Institute of Water Problems, Northern Karelian Scientific Center of the Russian Academy of Sciences, Petrozavodsk. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 784–789, November-December, 1995. Original article submitted December 13, 1994.     

Oxidation of metallic copper with complexones in organic media

Direct oxidation of copper in organic media with complexones (sterically hindered o-quinones; acetylacetone and pyridine as stabilizing ligands) was studied. From the complexes obtained, the initial components can be regenerated.     

Synthesis of poly(arylene ether ketones) with terminal phenolic groups

Poly(arylene ether ketones) with preset molecular weights (reduced viscosity from 0. 2 to 0.82 dL g^–1) containing terminal phenolic groups were synthesized by the reactions of 4,4-difluorobenzophenone with bisphenol A or phenolphthalein in the presence of K₂CO₃ in N,N-dimethylacetamide. The influence of an excess of bisphenols on the molecular weights of the polymers obtained was studied. The structures of the polymers were confirmed by ¹H NMR spectroscopy. The molecular weight distributions of the polymers were determined.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1958–1961, September, 2004.     

Equilibrium structures and flows of polar and nonpolar liquids in different carbon nanotubes

Molecular dynamics (MD) simulations of equilibrium structures and flows of polar water and nonpolar methane confined by single-walled carbon nanotubes (SWCNTs) with circular and square cross sections and bounding walls with regular graphene structure and random (amorphous) distribution of carbon atoms have been performed. The results of these simulations show that equilibrium structures of both confined liquids depend strongly on the shape of the cross section of SWCNTs, whereas the structure of their bounding walls has a minor influence on these structures. On contrary, the external pressure driven water and methane flows through above mentioned SWCNTs depend significantly on both the shape of their cross sections and the structure of their bounding walls.