Publications by authors named "K S Cheung Tung Shing"
As nitrogen analogues of iron-oxo species, high-valent iron-imido species have attracted great interest in the past decades. Fe-alkylimido species are generally considered to be key reaction intermediates in Fe(III)-catalyzed C(sp)─H bond aminations of alkyl azides but remain underexplored. Here, it is reported that iron-corrole (Cor) complexes can catalyze a wide range of intramolecular C─H amination reactions of alkyl azides to afford a variety of 5-, 6- and 7-membered N-heterocycles, including alkaloids and natural product derivatives, with up to 3880 turnover numbers (TONs) and excellent diastereoselectivity (>99:1 d.
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- * Traditional delivery methods for gene therapy face challenges due to the blood-brain barrier, but focused ultrasound (FUS) offers a non-invasive alternative to enhance gene delivery.
- * In studies with AAV9 vectors in both wild-type and HD mouse models, FUS successfully improved delivery efficacy, although there were concerns regarding decreased gene expression in older HD mice without increasing astrocytosis.
Article Synopsis
- A missense mutation in the Nucleus accumbens-associated 1 (NACC1) gene causes severe neurodevelopmental delays, as shown by the engineered mouse model with the same mutation.
- The model exhibited symptoms like delayed weight gain, seizures, altered brain activity, and specific behaviors, particularly in females.
- RNA sequencing from the mutant mice indicated substantial changes in gene expression related to synaptic functions and metabolism, suggesting potential targets for therapy in autism-related disorders.
Terminal Ru(v)-imido species are thought to be as reactive to group transfer reactions as their Ru(v)-oxo homologues, but are less studied. With the electron-rich corrole ligand, relatively stable and isolable Ru(v)-arylimido complexes [Ru(Bu-Cor)(NAr)] (H(Bu-Cor) = 5,15-diphenyl-10-(-butylphenyl)corrole, Ar = 2,4,6-MeCH (Mes), 2,6-(Pr)CH (Dipp), 2,4,6-(Pr)CH (Tipp), and 3,5-(CF)CH (BTF)) can be prepared from [Ru(Bu-Cor)] under strongly reducing conditions. This type of Ru(v)-monoarylimido corrole complex with = ½ was characterized by high-resolution ESI mass spectrometry, X-band EPR, resonance Raman spectroscopy, magnetic susceptibility, and elemental analysis, together with computational studies.
View Article and Find Full Text PDFExpansion of a triplet repeat tract in exon 1 of the HTT gene causes Huntington's disease (HD). The mutant HTT protein (mHTT) has numerous aberrant interactions with diverse, pleiomorphic effects. Lowering mHTT is a promising approach to treat HD, but it is unclear when lowering should be initiated, how much is necessary, and what duration should occur to achieve benefits.
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