A Novel Neurotrophic Drug for Cognitive Enhancement and Alzheimer's Disease

Currently, the major drug discovery paradigm for neurodegenerative diseases is based upon high affinity ligands for single disease-specific targets. For Alzheimer's disease (AD), the focus is the amyloid beta peptide (Aß) that mediates familial Alzheimer's disease pathology. However, given that age is the greatest risk factor for AD, we explored an alternative drug discovery scheme that is based upon efficacy in multiple cell culture models of age-associated pathologies rather than exclusively amyloid metabolism. Using this approach, we identified an exceptionally potent, orally active, neurotrophic molecule that facilitates memory in normal rodents, and prevents the loss of synaptic proteins and cognitive decline in a transgenic AD mouse model

Role of edge atoms in the hysteretic behaviour of 3D spin crossover nanoparticles revealed by an Ising-like model

We have applied a phenomenological two-level Ising-like model to study the case of 3D coordination polymers showing strongly cooperative but incomplete spin-transition behaviour. Our numerical results focus on nanoparticles of the cyanide-bridged 3D network Fe(pyrazine)[Pt(CN)4], considering several factors (i.e. temperature, pressure), the role of short- and long-range interactions and the system size. To be consistent with the experimental studies on a nanometric scale, we used a semiexact method (Monte Carlo entropic sampling) to solve a system that contains molecules on each surface in the high-spin state (edge atoms). A preliminary analysis of the short-range antiferromagnetic case has been carried out to illustrate the three-step transition case. The effects of system size, pressure and short-/long-range interactions for incomplete spin transitions, modelled by using a 3D Ising-like model, are discussed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Analysis of spin crossover nanochains using parabolic approximation in the framework of atom–phonon coupling model

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Analysis of the hysteretic behaviour of 3D spin crossover compounds by using an ising-like model

In this contribution, we use a recently developed Monte Carlo technique to investigate the impact of ferro-, antiferromagnetic interactions for different thermodynamic parameters in a three-dimensional Ising-like model. We present the role of temperature and pressure on the first-order phase-transition between a low-spin and a high-spin state and identify different response curves. The analysis of one- and two-step spin-crossover behaviour has been performed by using a self-consistent approach, because it is known that for a system with both short- and long-range interactions, the Hamiltonian does not have an exact solution. However, by constructing the distributions of the states with Monte Carlo entropic sampling and by taking into account the temperature degeneracy dependence between low-spin and high-spin states, we could solve the Hamiltonian. We provide herein a systematic comparison to our previous experimental works and as part of our continuous interest in spin crossover nanosystems, we present a size effect study. The effects of size, pressure and interactions on 3D spin crossover systems within the framework of an Ising-like model are discussed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Determinarea capacitătii antioxidante totale a unor vinuri roşii prin metode electrometrice şi spectrofotometrice

Phenolic compounds from various food matrices can be investigated with different analytical techniques such as spectrophotometric, cromatographic or electrochemic methods. Cupric Reducing Antioxidant Capacity method (CUPRAC) is a convenient assay for determining total antioxidant capacity in food substrates. In this work, electrochemical and spectrophotometrical approaches were used to estimate the total antioxidant capacity by means of an alternative of the CUPRAC assay, as the concentrations of the participating species ([Cu(Nc)2]2+ and [Cu(Nc)2]1+) can be evaluated by electrochemical and spectrophotometrical methods. The electrometric–CUPRAC methods have been applied to measure total antioxidant capacity of different local wines and validated against the spectrophotometric CUPRAC assay. The electrochemical methods proved to be easy, fast and with low detection limits. A good correlation for the total antioxidant capacity determined by CUPRAC spectrofotometric and electrometric method versus total phenol content (determined by Folin-Ciocalteu Method) was recorded, wich highlights that wines antioxidant activity results mainly from their phenolics content