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Introduction Predicting the shape of the occluded middle cerebral artery (MCA) from the contralateral MCA might help catheterization in endovascular mechanical thrombectomy (EMT). Materials and Methods We analyzed magnetic resonance (MR) angiography in 100 consecutive patients who had MR imaging for diseases other than acute ischemic stroke. To assess the symmetricity of MCA, the shape of M1, length of M1, number of M2, number of early branches (EBs), and distance from the top of the internal carotid artery to EB were investigated. Results The shape of M1 was upward in 42%, horizontal in 47%, and downward in 11%. The M1 shape was the same on both sides in 64%, which exceeded the probability assumed to be left–right independent. The number of M2 trunks and EBs matched left and right in 86 and 55% of patients, respectively; however, these agreement rates were not higher than those with independent left and right sides. No left–right correlation was found between the M1 length and the distance from the internal carotid artery to EB. Conclusion Based on our data, the symmetry of MCA was observed only in the shape of the M1 segment. This finding could be beneficial for EMT targeting MCA embolisms. [ABSTRACT FROM AUTHOR]

A theoretical thermodynamic study was conducted to investigate the antioxidant activity and mechanism of 1,3,4-oxadiazol-2-ylthieno[2,3-d]pyrimidin-4-amine derivatives (OTP) using a Density Functional Theory (DFT) approach. The study assessed how solvent environments influence the antioxidant properties of these derivatives. With the increasing prevalence of diseases linked to oxidative stress, such as cancer and cardiovascular diseases, antioxidants are crucial in mitigating the damage caused by free radicals. Previous research has demonstrated the remarkable scavenging abilities of 1,3,4-oxadiazole derivatives, prompting this investigation into their potential using computational methods. DFT calculations were employed to analyze key parameters, including bond dissociation enthalpy (BDE), ionization potential (IP), proton dissociation enthalpy (PDE), and electron transfer enthalpy (ETE), to delineate the antioxidant mechanisms of these compounds. Our findings indicate that specific electron-donating groups such as amine on the phenyl rings significantly enhance the antioxidant activities of these derivatives. The study also integrates global and local reactivity descriptors, such as Fukui functions and HOMO-LUMO energies, to predict the stability and reactivity of these molecules, providing insights into their potential as effective synthetic antioxidants in pharmaceutical applications. [ABSTRACT FROM AUTHOR]

This study investigated emissive urea compounds with an anthryl moiety on one side and a substituent group (biphenyl, naphthyl, benzyl, or cyclohexyl) on the other side across from the urea group. This was performed to determine the contribution of π-conjugation on a substituent group to excited-state intermolecular proton-transfer (ESPT) reactions in the presence of acetate anions. Fluorescence lifetime measurements revealed that the rate constant of the ESPT reaction from the normal form to the tautomer form increased with the length of the π-conjugation. Considering that there were a few differences among the wavelengths of the fluorescence maxima for the anthracene–urea derivatives in the presence of acetate anions, we observed that the extension of π-conjugation promoted tautomer formation. This maintained the energy levels of the normal and tautomer forms in the excited state. Furthermore, an anthracene–urea derivative without π-conjugation did not undergo a reverse ESPT reaction, implying that π-conjugation is considerably involved in the reverse ESPT reaction from the tautomer form to the normal form. [ABSTRACT FROM AUTHOR]

[Display omitted] The cross-coupling reaction of chlorobenzene and phenylboronic acid, catalyzed by the [R 3 Si–IPr]Pd0 species (generated upon activation of {[R 3 Si–IPr]Pd(173-allyl)Cl} pre-catalyst complexes) in the presence of hydroxide ion as a base, was studied in details by the quantum chemical calculations. Each step of the whole process, including pre- catalyst activation, oxidative addition, transmetalation and reductive elimination, were computationally probed to locate reaction intermediates and transition states along the reaction coordinate. Accordingly, transmetalation was found to be a limiting step of the catalytic cycle (involving oxidative addition, transmetalation and reductive elimination), whereas pre-catalyst activation was revealed as a limiting step of the whole catalytic process. [ABSTRACT FROM AUTHOR]