MTA-SZTE Research Group on Artificial Intelligence
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Synthesis of a fac -Tricarbonylrhenium(I) Complex with Pyrithione, Its Physicochemical Characterization, and Assessment of Biological Effects
Get PDFResearch on rhenium complexes containing fac-tricarbonyl fragments has been on the rise in recent decades. Some complexes of this type exhibit advantageous properties that can be utilized in diagnostic and therapeutic applications. Herein, we report on the synthesis, structural characterization, solution speciation, and biological activity with mode of action studies of a new fac-tricarbonylrhenium(I) complex with pyrithione ligand fac-[Re(CO)3(pyrithionato)(benzonitrile)] (4). In an attempt to prepare a stable rhenium(I) complex with a pyrithionato ligand, several synthesis procedures were investigated and various products were discovered. In solution, the monodentate benzonitrile ligand can be replaced by a coordinating solvent molecule; however, the carbonyl ligands and pyrithione remain bound to the rhenium center. Complex 4 exhibited strong cytotoxic and antibacterial activity and effectively inhibited the growth of the HSV-2 virus. Additionally, complex 4 was also able to inhibit the cathepsin B enzyme (both its endo- and exopeptidase activities). In silico experiments confirmed that complex 4 can interact with cathepsin B near its active site, which may contribute to reduced enzymatic activity
Electrophysiology and Morphology of Human Cortical Supragranular Pyramidal Cells in a Wide Age Range
Get PDFThe basic excitatory neurons of the cerebral cortex, the pyramidal cells, are the most important signal integrators for the local circuit. They have quite characteristic morphological and electrophysiological properties that are known to be largely constant with age in the young and adult cortex. However, the brain undergoes several dynamic changes throughout life, such as in the phases of early development and cognitive decline in the aging brain. We set out to search for intrinsic cellular changes in supragranular pyramidal cells across a broad age range: from birth to 85 years of age and we found differences in several biophysical properties between defined age groups. During the first year of life, subthreshold and suprathreshold electrophysiological properties changed in a way that shows that pyramidal cells become less excitable with maturation, but also become temporarily more precise. According to our findings, the morphological features of the three-dimensional reconstructions from different life stages showed consistent morphological properties and systematic dendritic spine analysis of an infantile and an old pyramidal cell showed clear significant differences in the distribution of spine shapes. Overall, the changes that occur during development and aging may have lasting effects on the properties of pyramidal cells in the cerebral cortex. Understanding these changes is important to unravel the complex mechanisms underlying brain development, cognition and age-related neurodegenerative diseases
A New Scale for Assessing Benzodiazepine Use Motives Among Community and Clinical Samples: The Development and Validation of the MBUQ- 48
Get PDFThe risk for non-medical use and dependence on benzodiazepines (BZDs) is high. However, there is no available validated psychometric instrument that assesses the motives for BZD use. Therefore, the aim of the present study was to develop a scale identifying the motives for BZD use, examine the factor structure, and corroborate the construct validity of the scale. Items for the scale were generated from previous data collection and from the empirical literature. Consequently, 82 motives were tested among a large community ( N = 1424) and a clinical sample ( N = 113). Medical and non-medical BZD use, other substance use, and several psychological constructs were assessed in both samples. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), as well as bivariate correlations and regression analyses, were performed. The EFA model included 48 items with four factors: “personal and interpersonal benefits”, “substance use regulation”, “coping”, and “sleep facilitation”. The four-factor CFA model demonstrated adequate levels of model fit. Members of the clinical sample had significantly higher rates of all four motives. The construct validity of the Motives for Benzodiazepine Use Questionnaire (MBUQ-48) was supported by positive correlations between the motivational factors and psychological constructs, different outcomes of BZD use, and other substance use. Coping motives had positive association with various outcomes of BZD use. Based on the results, the MBUQ-48 is a reliable and valid scale for assessing motives for BZD use. Exploring the motivations underlying BZD use can help clinicians in the recognition of the risk of BZD use disorder and in increasing the efficacy of therapeutic processes
Exact quantum dynamics of methanol: Full-dimensional ab initio potential energy surface of spectroscopic quality and variational vibrational states
No full textThe methanol molecule is a sensitive probe of astrochemistry, astrophysics, and fundamental physics. The first-principles elucidation and prediction of its rotational–torsional–vibrational motions are enabled in this work by the computation of a full-dimensional, ab initio potential energy surface (PES) and numerically exact quantum dynamics. An active-learning approach is used to sample explicitly correlated coupled-cluster electronic energies, and the datapoints are fitted with permutationally invariant polynomials to obtain a spectroscopic-quality PES representation. Variational vibrational energies and corresponding tunneling splittings are computed up to the first overtone of the C–O stretching mode by direct numerical solution of the vibrational Schrödinger equation with optimal internal coordinates and efficient basis and grid truncation techniques. As a result, the computed vibrational band origins finally agree with experiment within 5 cm−1, allowing for the exploration of the large-amplitude quantum mechanical motion and tunneling splittings coupled with the small-amplitude vibrational dynamics. These developments open the route toward simulating rovibrational spectra used to probe methanol in outer space and in precision science laboratories, as well as for probing interactions with external magnetic fields
