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The neurological complications following cardiovascular surgery can significantly affect the prognosis of patients. As a convenient and non⁃invasive intraoperative neurological monitoring method, transcranial Doppler ultrasonography (TCD) can provide real⁃time assessment of cerebral hemodynamics and microemboli signals, guide the development of neuroprotective strategies, and reduce the brain injury events. This review systematically summarizes the basic methods and technical performance of TCD monitoring, its clinical application in cardiovascular surgery, as well as the main limitations and future trends of this technology, in order to improve perioperative safety.

Catalytic enantioselection usually depends on differences in steric interactions between prochiral substrates and a chiral catalyst. We have discovered a carbene Si-H insertion in which the enantioselectivity depends primarily on the electronic characteristics of the carbene substrate, and the log(er) values are linearly related to Hammett parameters. A new class of chiral tetraphosphate dirhodium catalysts was developed; it shows excellent activity and enantioselectivity for the insertion of diarylcarbenes into the Si-H bond of silanes. Computational and mechanistic studies show how the electronic differences between the two aryls of the carbene lead to differences in energies of the diastereomeric transition states. This study provides a new strategy for asymmetric catalysis exploiting the electronic properties of the substrates.

A method for the synthesis of natural lignan lactones was developed by utilizing chiral dirhodium(II) carboxamidate catalysts. The synthetic process is characterized by C-H insertion which was initiated by the overlap of the carbon p-orbital and sigma-orbital of the metal carbene and the reacting C-H bond. The formation of beta-substituted-gamma-butyrolactones was initiated by the reaction of chiral Rh2(MPPIM)4 catalysts to fully aliphatic systems.

A method for the synthesis of natural lignan lactones was developed by utilizing chiral dirhodium(II) carboxamidate catalysts. The synthetic process is characterized by C-H insertion which was initiated by the overlap of the carbon p-orbital and sigma-orbital of the metal carbene and the reacting C-H bond. The formation of beta-substituted-gamma-butyrolactones was initiated by the reaction of chiral Rh2(MPPIM)4 catalysts to fully aliphatic systems.

This study was designed to determine whether plasma CXCL12 levels in postmenopausal osteoporosis (PMOP) patients are related to disease severity. A total of 91 PMOP females were recruited, and 88 postmenopausal non-osteoporotic (PMNOP) women and 90 healthy females were incorporated as controls. Dual-energy X-ray absorptiometry was utilised to explore bone-mineral density (BMD). The Genant semi-quantitative grading scale was used for vertebral fractures, and plasma CXCL12/SDF-1 levels were investigated by ELISA. Plasma TNF-α and C-telopeptide cross-linked collagen type 1 (CTX-1) were also tested. The Oswestry Disability Index (ODI) and a visual analogue scale (VAS) were completed in order to assess clinical severity. Plasma CXCL12 levels were considerably elevated in PMOP females compared to PMNOP women and healthy controls. Plasma CXCL12 concentrations were positively correlated with the Genant grading system. We observed significant and negative correlations of plasma CXCL12 levels with lumbar spine, femoral neck and total hip BMD. Moreover, plasma CXCL12 concentrations were positively correlated to VAS and ODI, as well as plasma TNF-α and CTX-1 levels. In conclusion, elevated plasma CXCL12 levels are correlated with disease severity in PMOP females. [ABSTRACT FROM AUTHOR]

A new, efficient carbon-hydrogen insertion methodology is used for the highly enantio- and regioselective syntheses of natural dibenzylbutyrolactone lignans from 3-aryl-1-propyl diazoacetates using chiral oxoimidazolidine carboxylate-ligated dirhodium(II) catalysts. The dirhodium catalysts are prepared from m-1-(3-phenylpropanoyl)-2-oxoimidazolidine-4(S)-carboxylate and its 4(R) enantiomer. The openness in the area around the rhodium catalyst, Rh2(4-R-MPPIM)4 allows insertion of the C-H bond.