Search results for "Function"
showing 10 items of 14432 documents
Efficient synthesis of new C-functionalized macrocyclic polyamines
2010
A powerful synthetic route for the preparation of new poly-azamacrocycles, valuable precursors of bifunctional chelating agents with applications in nuclear medicine, is reported. The desired functional group was introduced onto the macro-cycle backbone during the cyclization step, thus avoiding the tedious preparation of a C-functionalized synthon. The regioselective reaction of macrocycles bearing an aminomethyl pendant arm with aldehydes is also described.
Distinctive amino acid residue periodicities in terminal sequences of type III and type I secreted proteins from proteobacteria
2007
AbstractThe Fourier transform (FT) method was applied to specify the distribution of 14 predefined groups of amino acids (64 residues) at both termini of annotated type III and type I secreted proteins from proteobacteria. Type I proteins displayed a higher occurrence of significant periodicities at both C-and N-termini, indicating potent features to discriminate between secretion types, particularly by the use of variables selected from the full periodicity profiles at 19 orders of FT. The Fishers linear discriminant analysis, together with the stepwise selection of variables throughout equal pairs of combinations for all predefined groups of residues, revealed the C-terminal harmonics of …
Synthesis of highly functionalized β-aminocyclopentanecarboxylate stereoisomers by reductive ring opening reaction of isoxazolines
2012
A rapid and simple procedure was devised for the synthesis of multifunctionalized cyclic β-amino esters and γ-amino alcohols via the 1,3-dipolar cycloaddition of nitrile oxides to β-aminocyclopentenecarboxylates. The opening of the isoxazoline reductive ring to the corresponding highly functionalized 2-aminocyclopentanecarboxylates occurred stereoselectively with good yields.
Oligomeric State and Holding Activity of Hsp60
2023
Similar to its bacterial homolog GroEL, Hsp60 in oligomeric conformation is known to work as a folding machine, with the assistance of co-chaperonin Hsp10 and ATP. However, recent results have evidenced that Hsp60 can stabilize aggregation-prone molecules in the absence of Hsp10 and ATP by a different, “holding-like” mechanism. Here, we investigated the relationship between the oligomeric conformation of Hsp60 and its ability to inhibit fibrillization of the Ab40 peptide. The monomeric or tetradecameric form of the protein was isolated, and its effect on beta-amyloid aggregation was separately tested. The structural stability of the two forms of Hsp60 was also investigated using differentia…
FATIGUE, SLEEP, AND NOCTURNAL COMPLAINTS IN PATIENTS WITH AMYOTROPHIC LATERAL SCLEROSIS.
2012
Background and purpose: Fatigue is a common symptom in amyotrophic lateral sclerosis (ALS). Although sleep disturbances are a candidate factor that may interfere with fatigue in patients with ALS, the role of sleep-related abnormalities in determining fatigue in ALS is unknown. Objective: To evaluate the frequency and determinants of fatigue in a group of 91 consecutive patients with ALS, with special attention to the relationship between fatigue and sleep problems. Methods: Measures included the Fatigue Severity Scale (FSS), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), ALS Functional Rating Scale- Revised (ALSFRS-R), and Beck Depression Inventory (BDI). Results: T…
High frequency rTMS over the left parietal lobule increases non-word reading accuracy
2012
Increasing evidence in the literature supports the usefulness of Transcranial Magnetic Stimulation (TMS) in studying reading processes. Two brain regions are primarily involved in phonological decoding: the left superior temporal gyrus (STG), which is associated with the auditory representation of spoken words, and the left inferior parietal lobe (IPL), which operates in phonological computation. This study aimed to clarify the specific contribution of IPL and STG to reading aloud and to evaluate the possibility of modulating healthy participants' task performance using high frequency repetitive TMS (hf-rTMS). The main finding is that hf-rTMS over the left IPL improves non-word reading accu…
Mutual inductance for an explicitly finite number of turns
2011
Published version of an article published in Progress In Electromagnetics Research B, 28, 273-287. Also available from the publisher at http://www.jpier.org/pierb/pier.php?paper=10110103 Non coaxial mutual inductance calculations, based on a Bessel function formulation, are presented for coils modelled by an explicitly finite number of circular turns. The mutual inductance of two such turns can be expressed as an integral of a product of three Bessel functions and an exponential factor, and it is shown that the exponential factors can be analytically summed as a simple geometric progression, or other related sums. This allows the mutual inductance of two thin solenoids to be expressed as an…
Unveiling the Unexpected Reactivity of Electrophilic Diazoalkanes in [3+2] Cycloaddition Reactions within Molecular Electron Density Theory
2021
The [3+2] cycloaddition (32CA) reactions of strongly nucleophilic norbornadiene (NBD), with simplest diazoalkane (DAA) and three DAAs of increased electrophilicity, have been studied within the Molecular Electron Density Theory (MEDT) at the MPWB1K/6-311G (d,p) computational level. These pmr-type 32CA reactions follow an asynchronous one-step mechanism with activation enthalpies ranging from 17.7 to 27.9 kcal·
Unveiling the Different Reactivity of Bent and Linear Three-Atom-Components Participating in [3 + 2] Cycloaddition Reactions
2021
The reactivity of a series of pairs of bent and linear three-atom-component (B-TACs and L-TACs) participating in [3 + 2] cycloaddition (32CA) reactions towards ethylene and electrophilic dicyanoethylene (DCE) have been studied within the Molecular Electron Density Theory. While the pseudodiradical structure of B-TACs changes to that of pseudoradical or carbenoid L-TACs upon dehydrogenation, zwitterionic B-TACs remain unchanged. Conceptual Density Functional Theory (CDFT) indices characterize five of the nine TACs as strong nucleophiles participating in polar reactions towards electrophilic ethylenes. The activation energies of the 32CA reactions with electrophilic DCE range from 0.5 to 22.0…
Effect of dual blockade of renin-angiotensin system on TGF beta 1 and left ventricular structure and function in hypertensive patients
2007
The effects of 24 weeks losartan and ramipril treatment,both alone and in combination, on left ventricular mass (LVM), circulating transforming growth factor b1(TGFb1), procollagen type I (PIP) and III (PIIIP), havebeen evaluated in hypertensive (HT) patients. A total of 57 HT with stage 1 and 2 essential hypertension were included. After 4 weeks run in, a randomized double blind, three arms, double dummy, independent trial was used. All HT patients were randomly allocated to three treatment arms consisting of losartan (50 mg/daily),ramipril (5 mg/ daily) and combined (losartan 50 mg/daily plus ramipril 5 mg/daily) for 24 weeks. TGFb1, PIP and PIIIP, LVM, LVM/h 2.7 and other echocardiograph…