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Background: The optimization of myocardial CT perfusion (CTP) assessment remains inconsistent and uncertain. Our aim was to explore the superior analysis selection and incremental improvement of myocardial blood flow (MBF) assessment on CTP in diagnosing hemodynamically significant coronary artery disease (CAD)., Methods: Sixty patients (43 men and 17 women; 61.38 ± 8.01 years) were prospectively recruited and underwent stress dynamic myocardial CTP examinations. Absolute and relative MBF was used for ischemia evaluation with the invasive coronary angiography and fractional flow reserve were used as the reference standard. Areas under the receiver operating characteristic curves (AUCs) and cutoff values were calculated and compared., Results: There were 151 vessels in 60 patients finally enrolled for analysis. The sensitivity, specificity, PPV, NPV and diagnostic accuracy for the absolute MBF value and relative MBF ratio were 82.76%, 98.92%, 97.96%, 90.20%, and 92.72% and 74.14%, 93.56%, 87.76%, 85.29%, and 86.09%, respectively. The absolute MBF value was superior than the relative MBF ratio in detecting ischemia (AUC, 0.955 [95%CI: 0.919-0.990] vs.0.906 [95%CI:0.857-0.954])(P = 0.02). For territories with both sensitivity and specificity ≤90%, the diagnostic accuracy increased from 79.1% to 88.4% when the specific data were assessed using the absolute MBF value instead of the relative MBF ratio., Conclusions: The absolute MBF value from the endocardial myocardium on stress dynamic myocardial CTP showed superior diagnostic performance compared to the relative MBF ratio for the detection of myocardial ischemia in intermediate-to-high risk patients. The absolute MBF value provides an incremental benefit toward diagnostic performance for the relative MBF ratio evaluation., Competing Interests: Declaration of competing interest All the other authors have no conflict of interest to disclose., (Copyright © 2020 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Considering the excellent photochemical properties of ruthenium(II) complexes, two new ruthenium(II) complexes, RuL 1 -DNBS and RuL 2 -DNBS, have been developed as phosphorescence probes for detection of biothiols in 100:1 (v/v) Hepes buffer (20 mM, pH = 7.2)/CH 3 CN solution. The response rate was highly improved of these two probes toward biothiols because the steric interactions between 1H-imidazo [4, 5-f] [1,10] phenanthroline group and ortho-2, 4-dinitrobenzensulfonate resulted in a relatively rapid thiol-induced S N Ar substitution reaction. RuL 1 -DNBS and RuL 2 -DNBS were weakly phosphorescent owing to the effectual photoinduced electron transfer from ruthenium(II) luminophore to the sensing group, 2,4-dinitrobenzenesulfonyl. After reacting with biothiols, the 2,4-dinitrobenzenesulfonyl group of RuL 1 -DNBS and RuL 2 -DNBS were cleavaged and the RuL 1 and RuL 2 were obtained. Meanwhile, the phosphorescence were "turn-on". Both of these two probes can detect biothiols sensitively and selectively under physiological conditions with submicromolar detection limits. Furthermore, application of RuL 2 -DNBS for detecting of intracellular biothiols has been successfully performed in living Glioma cells., (Copyright © 2019. Published by Elsevier B.V.)

A series of novel 2-acyl-6-aryl substituted indolizine derivatives was synthesized by a novel tandem reaction between 4-acyl-pyrrole-2-carbaldehyde derivatives and ethyl 4-bromo-3-arylbut-2-enoate under mild conditions. The compounds were characterized using IR, (1)H NMR (13)C NMR and HRMS. The crystal structure of 7a was determined using single crystal X-ray crystallography. The absorption results showed that compounds 7a-e presented their absorption maxima at ca. 270 nm, while compounds 7f and 7g with a larger conjugation system exhibited red-shifted absorption character (ca. 280 nm). Fluorescence spectra revealed that these compounds exhibited blue fluorescence (434-456 nm) in dilute solutions and showed quantum yields of fluorescence between 0.02 and 0.39 in dichloromethane., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A series of novel 5-(3-aryl-1H-pyrazol-5-yl)-2-(3-butyl-1-chloroimidazo[1,5-a]- pyridin-7-yl)-1,3,4-oxadiazole derivatives has been synthesized from 3-butyl-1-chloroimidazo[1,5-a]pyridine-7-carboxylic acid and ethyl 3-aryl-1H-pyrazole-5-carboxylate. The compounds were characterized using IR, (1)H NMR, HRMS and UV-vis absorption. The fluorescence spectral characteristics of the compounds in dichloromethane were investigated. The results showed that absorption λmax and emission λmax was less correlated with substituent groups on N-1 position of pyrazole moiety and para position of benzene moiety. The calculated molecular orbital correlates well with their absorption., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A series of novel 5-aryl-3-benzimidazolyl-1-phenyl-pyrazoline derivatives were synthesized by the reaction of benzimidazolyl chalcone and phenylhydrazine in 41-72% yields. The compounds were characterized using IR, (1)H NMR and HRMS. Absorption and fluorescence spectra were measured in different organic solvent. An intense absorption maxima was noted at ca. 370 nm and emission maxima was noted at ca. 460 nm. The absorption spectra of the pyrazoline derivatives reveal that 5-aryl group attached to the pyrazoline ring hardly influenced the maximum absorption. The fluorescence spectra of these compounds indicated the emission wavelength was red shifted and the fluorescence intensity was decreased with the increase in solvent polarity., (Copyright © 2012 Elsevier B.V. All rights reserved.)