Publications by authors named "Wan-Wan Yang"

Aims: We conducted this study to investigate the impact of muscle loss on musculoskeletal health, fall and fracture risks, and activities of daily living (ADL) in elderly patients with osteoporosis.

Materials And Methods: This age- and sex-matched cross-sectional study analyzed data from a medical center involving patients aged ≥ 50 from 2020 to 2022. The included participants were formed into three groups: 100 with osteoporosis only, 100 with osteosarcopenia, and 50 control individuals without osteoporosis and sarcopenia.

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A simple and efficient base-mediated decarboxylative annulation of ynones with methyl 2-(2-bromophenyl)acetates has been developed. A broad range of benzoxepines were prepared with a broad substrate scope and high regioselectivity in moderate to excellent yields under transition-metal-free conditions. This method proceeds through a tandem [2 + 4] annulation, ring-opening decarboxylative reaction, and the intramolecular nucleophilic aromatic substitution reaction.

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A facile and efficient base-mediated divergent annulation of methyl 2-(cyanomethyl)benzoates and conjugated ynones has been described. A broad range of 1-naphthols and xanthones were formed in moderate to excellent yields. The notable features of this protocol include readily available precursors, broad substrate scope, complete regioselectivity, and substrate-controlled divergent synthesis.

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A simple and effective tandem reaction of diynones and allylic alcohols was developed to afford functionalized 3-allyl-4-pyrones in moderate to excellent yields. This protocol underwent a Michael addition─Claisen rearrangement─O-cyclization process, which exhibited broad substrate tolerance, high regioselectivity, and atom economy under a metal-free condition. Moreover, functional transformation of the products was also further studied.

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A simple and effective annulation of ynediones and (iso)quinoline -oxides was developed to afford various functionalized pyrrolo[2,1-]isoquinolines and pyrrolo[1,2-]quinolines in moderate to excellent yields. This protocol underwent a tandem [3 + 2] cycloaddition/ring-opening/-nucleophilic addition, which exhibited high regioselectivity, broad substrate tolerance, and atom economy under catalyst-, additive-free, and air conditions. Moreover, indolizine was also successfully prepared using pyridine -oxide.

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An effective annulation of ynones and (iso)quinoline N-oxides was developed to deliver various functionalized 3-((iso)quinolin-1-yl)-4H-chromen-4-ones and 13H-isoquinolino[2,1-a]quinolin-13-ones in moderate to excellent yields, respectively. This protocol exhibits high regioselectivity and broad substrate scope under transition-metal-free conditions. Moreover, the key reaction intermediate was successfully isolated and determined unambiguously by single crystal X-ray crystallography.

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An effective electrophilic annulation reaction of azacyclic ynones was reported, divergently affording various functionalized 3-iodo-2H-quinolizin-2-ones and 1,3-diiodo-2H-quinolizin-2-ones in moderate to excellent yields with different iodide reagents. This reaction shows high regioselectivity and broad substrate scope under metal-free, room temperature conditions in air. In addition, the products with highly active C-I bonds have an opportunity for further functionalization.

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An effective transition-metal-free strategy was developed for the preparation of chromones from o-bromoaryl ynones and benzaldehyde oxime through sequential C-O bond formation. This cyclization reaction could well tolerate a wide range of functional groups, and the corresponding chromones were given in moderate to excellent yields. Mechanistically, benzaldehyde oxime as a hydroxide source and 1,3-diketone derivatives as reaction intermediates were involved in this transformation.

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An effective base-controlled divergent annulation reaction of 2-bromophenylacetonitriles and ynones has been developed. Various functionalized 5-cyanobenzoxepines and benzofuro[2,3-]pyridines were obtained with a broad substrate scope and high regioselectivity in moderate to excellent yield. Of importance, an unexpected O-rearrangement reaction to access benzofuro[2,3-]pyridines was observed using 1,8-diazabicyclo[5.

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Effective transition-metal-free formal [4+2] benzannulation for the preparation of 1-cyano-3-acylnaphthalenes from 2-(2-alkynylphenyl)acetonitriles and alkynones through sequential C-C bond coupling has been developed. This protocol is characterized by mild conditions, excellent functional group tolerance, complete regioselectivity, and atom economy. The plausible mechanism, gram-scale synthesis, and further transformations of the product were studied.

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Objective: Cisplatin is a chemotherapeutic drug known to induce hearing loss. Although corticosteroids may help to mitigate the ototoxic side effects of cisplatin, there are complications associated with their systemic and prolonged use. The goal of this study is to test the efficacy of extended-release fluticasone propionate intracochlear implant particles to protect against cisplatin-induced hearing loss.

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An effective and facile transition-metal-free method has been developed for the synthesis of β-ketophosphine oxides from alkynylphosphine oxides with benzaldehyde oxime as a hydroxide surrogate. The current methodology provides simple access to various β-ketophosphine oxides in moderate to excellent yields with a broad substrate scope.

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Objective: Investigate a new polymer-based drug coating suitability for safe intracochlear delivery and ability to maintain long-term physiologically active levels of the corticosteroid fluticasone propionate.

Study Design: In vitro dissolution study to evaluate release profiles of polymer-coated drug particles and in vivo studies using a guinea pig model to measure perilymph drug concentrations at specific time points after implantation with polymer-coated drug particles and evaluate their effect on hearing function.

Methods: Polymer-coated fluticasone propionate (FP) particles were surgically implanted in guinea pigs through the round window membrane into the cochlear scala tympani.

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Our study aims to investigate the effects of the inhalation of subanesthestic doses of sevoflurane combined with oxygen on sepsis. Male Sprague-Dawley rats or Male ICR/Km mice underwent caecal ligation and puncture (CLP) or intraperitoneal injection of lipopolysccharide (LPS) to induce sepsis, while sham rats were used as control. Then, rats were treated with the inhalation of sevoflurane in oxygen; and air or 100% oxygen was used as control.

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Background: Sepsis is a major cause of mortality in Intensive Care Units. Anesthetic dose isoflurane and 100% oxygen were proved to be beneficial in sepsis; however, their application in septic patients is limited because long-term hyperoxia may induce oxygen toxicity and anesthetic dose isoflurane has potential adverse consequences. This study was scheduled to find the optimal combination of isoflurane and oxygen in protecting experimental sepsis and its mechanisms.

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The importance of drug delivery has increased over the past decades, and significant advances have been made in the development of novel technologies. This review focuses on the use of different polymer drug delivery systems and their advancement toward clinical applications.

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A microscopy-based endospore viability assay (micro-EVA) capable of enumerating germinable Clostridium endospores (GCEs) in less than 30 min has been validated and employed to determine GCE concentrations in Greenland ices and Atacama Desert soils. Inoculation onto agarose doped with Tb(3+) and d-alanine triggers Clostridium spore germination and the concomitant release of ∼10(8) molecules of dipicolinic acid (DPA) per endospore, which, under pulsed UV excitation, enables enumeration of resultant green Tb(3+)-DPA luminescent spots as GCEs with time-gated luminescence microscopy. The intensity time courses of the luminescent spots were characteristic of stage I Clostridium spore germination dynamics.

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A rapid Endospore Viability Assay (EVA), previously developed for Bacillus spores, was modified for enumeration of germinable Clostridium sporogenes spores. The EVA is based on the detection of dipicolinic acid (DPA), which is released during stage I germination and quantified by terbium (III) ion Tb-DPA luminescence. Germination of C.

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Homoserine lactone (HSL) is a ubiquitous product of metabolism. It is generated by all known biota during the editing of certain mischarged aminoacyl-tRNA reactions, and is also released as a product of quorum signal degradation by bacterial species expressing acyl-HSL acylases. Little is known about its environmental fate over long or short periods of time.

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