Ru-Mg promoted reductive cross-coupling of allyl bromides and alkenes to synthesize 1,7-octadienes with an all-carbon quaternary center.

A Ru-promoted reductive cross-coupling of allyl bromides and electron-deficient alkenes to provide terminal 1,7-octadienes with magnesium as a reductant is reported herein. This approach enables the facile construction of a series of complex terminal 1,7-octadienes with an all-carbon quaternary center under mild reaction conditions, and the synthetic utility of the current method has been demonstrated by a gram scale synthesis. Preliminary mechanism investigations suggested that a radical pathway might not be involved in this transformation.

Controlled Synthesis of α-CFH or α-CFCl Styrenes from the Same Precursors: Dehydrazinative Hydrogenation or Chlorination of 3,3-Difluoroallyl Hydrazines.

By carefully choosing the reaction conditions, we have developed the controllable FeCl- or CuCl-mediated dehydrazinative hydrogenation or chlorination of 3,3-difluoroallyl hydrazines to access α-CFH or α-CFCl styrenes. The current reaction provides for the first time a facile method for the direct and selective synthesis of α-CFH and α-CFCl styrenes starting from the same precursors, which is easy to scale up and displays a broad substrate scope and good functional group tolerance. Moreover, product derivatization experiments demonstrated that the resulting α-CFCl styrenes are practical and versatile building blocks for the diversified synthesis of fluorinated molecules.

Novel electrochemical sensing platform basing on di-functional stimuli-responsive imprinted polymers for simultaneous extraction and determination of metronidazole.

A novel magnetic-controlled electrochemical sensor has been fabricated by combined photo-responsive surface molecular imprinted polymers (P-SMIPs) and electrochemical sensor. In particular, the P-SMIPs were obtained by living radical polymerization of photo-responsive functional monomer onto the magnetic FeO modified multi-walled carbon nanotubes nanocomposites. The magnetic glassy carbon electrode was introduced to make the anchoring and removal of P-SMIPs onto the magnetic-controlled glassy carbon electrode easy to manipulate.

Self-cleaning electrochemical protein-imprinting biosensor with a dual-driven switchable affinity for sensing bovine serum albumin.

A facile, universal and highly efficient approach for producing a self-cleaning electrochemical protein-imprinting biosensor based on dual stimuli-responsive memory hydrogels via free-radical polymerisation is described. As confirmed by static contact angle and scanning electron microscopy results, the imprinted hydrogels exhibited reversible conformational changes after being simulated by an external electric field and temperature. By exploring the properties of imprinted hydrogels for sensing applications, the electrochemical protein-imprinting biosensor was originally fabricated on a glassy carbon electrode using the drop-casting method.

Comparative morphology of the internal elastic lamina of cerebral and peripheral arteries.

Background: Atherosclerosis progresses later and with fewer complicated plaques in cerebral arteries than in peripheral arteries. The internal elastic lamina has been proposed to be important for the migration of smooth muscle cells into the intima during intimal thickening and atherosclerosis.

Methods: A total of 280 segments were retrieved from 14 autopsy specimens.

gem-Difluoroallylation of Aryl Diazoesters via Catalyst-Free, Blue-Light-Mediated Formal Doyle-Kirmse Reaction.

A first example of low-energy blue-light-mediated formal Doyle-Kirmse reaction for gem-difluoroallylation of aryl diazoesters has been developed. A variety of highly functionalized gem-difluoroallyl containing esters bearing transformable sulfur and bromine groups were efficiently assembled with broad substrate scope under mild, catalyst-free, and additive-free conditions. The reaction represents a practical and environmentally friendly approach for C-CF bond formation based on rearrangement strategy, which will find potential applications among drug discovery and development.

Supramolecularly imprinted polymeric solid phase microextraction coatings for synergetic recognition nitrophenols and bisphenol A.

We herein firstly presented supramolecularly imprinted polymeric (SMIP) solid phase microextraction (SPME) coatings which showed synergetic recognition for nitrophenols and bisphenol A. A series of β-cyclodextrins (β-CD) with different substituents were successfully designed and synthesized. It was employed as supramolecular functional monomers for SMIPs.

Copper-Catalyzed Dehydrogenative Formal [4 + 2] and [3 + 2] Cycloadditions of Methylnaphthalenes and Electron-Deficient Alkenes.

Higher π-extended naphthalene, contained in methylnaphthalenes, which could capture alkyl radicals via SOMO-LUMO interactions, enabled the development of Cu-catalyzed formal [4 + 2] and [3 + 2] cycloadditions between methylnaphthalenes and electron-deficient alkenes. Under copper catalysis, a series of electron-deficient alkenes and methylnaphthalenes with different substituents were successfully incorporated with di-tert-butyl peroxide (TBP) as an oxidant and radical initiator, providing a wide range of cycloadducts.

Silver-catalyzed nucleophilic substitution of aminals with ethyl diazoacetate: a new pathway to β-amino-α-diazoesters.

A novel silver-catalyzed nucleophilic substitution of aminals with ethyl diazoacetate producing β-amino-α-diazoesters has been developed. A series of aminals with different amino moieties and substituents were successfully incorporated in this reaction, which delivered a wide range of β-amino-α-diazocarbonyl compounds in the presence of a lower catalyst loading in 2 hours.

The Diagnostic Value of Gastrin-17 Detection in Atrophic Gastritis: A Meta-Analysis.

A meta-analysis was performed to assess the diagnostic value of gastrin-17 (G-17) for the early detection of chronic atrophic gastritis (CAG).An extensive literature search was performed, with the aim of selecting publications that reported the accuracy of G-17 in predicting CAG, in the following databases: PubMed, Science Direct, Web of Science, Chinese Biological Medicine, Chinese National Knowledge Infrastructure, Wanfang, and VIP. To assess the diagnostic value of G-17, the following statistics were estimated and described: sensitivity, specificity, diagnostic odds ratios (DOR), summary receiver operating characteristic curves, area under the curve (AUC), and 95% confidence intervals (CIs).

Palladium-Catalyzed Formal Insertion of Carbenoids into Aminals via C-N Bond Activation.

A new strategy for selective insertion of metal carbenes into C-N bond has been developed via Pd-catalyzed C-N bond activation. A series of aminals and α-diazoesters with different substituents were successfully incorporated even in 0.1 mol % of catalyst under mild conditions, affording a wide range of α,β-diamino acid esters with quarternary carbon-centers.

[Levels of polychlorinated biphenyls in Tibetan and Yi adolescents' hair from Liangshan Prefecture, Sichuan Province].

Adolescents' (11-19 years old) hair samples (n =39) collected from Liangshan prefecture, Sichuan Province were analyzed for 12 dioxin-like polychlorinated biphenyl(DL-PCBs) congeners by gas chromatography-mass spectrometry(GC-MS). The levels and distribution characteristics of DL-PCBs in Tibetan and Yi Adolescents' hair were studied, meanwhile, the relationships between the levels of DL-PCBs and the nationalities, eating habits and genders were addressed. The results indicated that the average concentration of PCBs was (102.

Generation, transmission and infectiosity of chicken MDV aerosols under experimental conditions.

To further investigate the airborne infection mechanism of Marek's disease virus (MDV), a MDV aerosol infection model was established, and the generation, transmission and infectiosity of MDV aerosols were monitored in this study. Two positive/negative pressure isolators, in which SPF chickens were raised, were connected with a closed conduit. Two repetitive trials, Trial 1 (T1) and Trial 2 (T2) were carried out for objective assessment.

Rh-catalyzed oxidative C-H activation/annulation: converting anilines to indoles using molecular oxygen as the sole oxidant.

A practical and efficient Rh(III)-catalyzed aerobic C-H activation has been developed for the facile synthesis of a broad range of indoles from simple anilines and alkynes. The protocol could be conducted under mild conditions and used environmentally friendly oxygen as the sole clear oxidant.