Post translational changes to α-synuclein control iron and dopamine trafficking : a concept for neuron vulnerability in Parkinson's disease

Parkinson's disease is a multifactorial neurodegenerative disorder, the aetiology of which remains elusive. The primary clinical feature of progressively impaired motor control is caused by a loss of midbrain substantia nigra dopamine neurons that have a high α-synuclein (α-syn) and iron content. α-Syn is a neuronal protein that is highly modified post-translationally and central to the Lewy body neuropathology of the disease. This review provides an overview of findings on the role post translational modifications to α-syn have in membrane binding and intracellular vesicle trafficking. Furthermore, we propose a concept in which acetylation and phosphorylation of α-syn modulate endocytic import of iron and vesicle transport of dopamine during normal physiology. Disregulated phosphorylation and oxidation of α-syn mediate iron and dopamine dependent oxidative stress through impaired cellular location and increase propensity for α-syn aggregation. The proposition highlights a connection between α-syn, iron and dopamine, three pathological components associated with disease progression in sporadic Parkinson's disease

Structural Preferences and Vibrational Analysis of 2-Hydroxy-2-methyl-1-phenylpropan-1-one: A Computational and Infrared Spectroscopic Research

The Fourier transform infrared (FTIR) spectrum of 2-hydroxy-2-methyl-1-phenylpropan-1-one has been measured in the region 4000–700 . The most stable conformation of title molecule was found after a careful potential energy surfaces study. The molecular geometry, vibrational frequencies, and infrared intensities have been calculated by using ab initio HF and density functional theory calculation B3LYP with 6-311+ basis set. Scaled frequencies and potential energy distribution were calculated for band assignment. We found an excellent agreement between the experimental and the simulated spectra. Energy gap between HOMO and LUMO explains the eventual charge transfer interactions taking place within the molecule

Accuracy and Applicability of the New Exchange Correlation Functionals for Reproduction of the Infrared Spectra of Butyl Acrylate and Butyl Methacrylate Molecules

The butyl acrylate and butyl methacrylate were optimized by seven functionals. All the structures found are local minima and belong to the Cs symmetry. The calculated frequencies are scaled and ranked according to their square errors. The scaling factors of the B972 and B98 functionals fail to reproduce the infrared spectra. The calculated and scaled frequencies with G96LYP, OLYP, and HCTH functionals give acceptable correlations with the experimental spectra. The scaling factors for O3LYP/6-31G(f,p) and O3LYP/6-311+G(df,p) levels of theory reproduce very well the infrared spectrum of butyl acrylate, and the scaled frequencies at VSXC functional with Pople’s double zeta basis sets show the best accuracy in the case of butyl methacrylate

Drug likeness scoring and quantitative structure anaplastic lymphoma kinase (ALK) inhibitors activities relationships of pyrazolone derivatives

Series of twenty-four compounds was the field for applying multi-parameter optimization (MPO) methods and qualitative approximations of structural activity relationships in order to determine the role of various physico-chemical and quantum descriptors used in QSAR modeling as independent variables. Anaplastic lymphoma kinase (ALK) inhibitory activity was considered as a component in this study. In order to illustrate the quantitative relationships between the molecular descriptors and the activity of pyrazolone derivatives, we have applied a multiple linear regression (MLR) procedure. By adopting cross-validation with the leave-one-out method, we could estimate the predictability of models. Our results suggest a QSAR model based on the following descriptors: S, V, LogP, POL, Ref, HOMO, LUMO, E, , HBA, PSA and NRB, for the inhibitory activities against ALK. Results show high correlation between experimental and predicted activity values, indicating the validation and the good quality of the QSAR model. Copyright © 2018 American Scientific Publishers All rights reserved

Structural investigation, drug likeness scoring and structure activity/property relationships applied on 1,2,3-thiadiazole derivatives, with kinase inhibitors activity

All calculations and the equilibrium geometries of 1,2,3-thiadiazole have been performed using ab initio/HF, MP2 and DFT methods with different basis sets. The molecular electrostatic potential surface (MESP) that reveals centers of reactivity of the molecule and substitution effects of the molecular system have been studied using the HSAB principle (Hard Soft Acid and Base). Also, the multi-parameter optimization (MPO) methods and structure activity/property relationship studies were carried out on twenty-one molecules of 1,2,3-thiadiazole derivatives which are potent VEGFR-2/KDR kinase inhibitors. In the present work results such as net charges, bond lengths, dipole moments, QSAR properties, Lipinski’s parameters, Lipophilic Efficiency (LipE), have been calculated and discussed. (Figure Presented). © 2017, Editura Academiei Romane. All rights reserved

Passivation of TiO2 by ultra thin Al oxide

The passivation of sol gel TiO2 by ultra thin layers of alumina has been investigated using transient and spectral photovoltage techniques. The ultra thin layers of alumina were prepared by the Ion Layer Gas Reaction ILGAR technique and modified by thermal treatments in air, vacuum or Ar H2S atmosphere. The samples where characterized by Elastic Recoil Detection Analysis ERDA , x ray photoelectron spectroscopy, and contact potential difference technique. Without an alumina surface layer, electronic states in the forbidden gap of TiO2 are formed during thermal treatment in vacuum and Ar H2S atmosphere as well. The trap density is strongly reduced at the TiO2 alumina interface. The formation of electronic defects is prevented by a closed ultra thin layer of alumina which stabilizes the chemical potential of oxygen at the TiO2 surfac