Palladium-catalyzed three-component radical-polar crossover carboamination of 1,3-dienes or allenes with diazo esters and amines.

Herein, we report a visible-light-mediated palladium-catalyzed three-component radical-polar crossover carboamination of 1,3-dienes or allenes with diazo esters and amines, affording unsaturated γ- and ε-amino acid derivatives with diverse structures. In this methodology, the diazo compound readily transforms into a hybrid α-ester alkylpalladium radical with the release of dinitrogen. The radical intermediate selectively adds to the double bond of a 1,3-diene or allene, followed by the allylpalladium radical-polar crossover path and selective allylic substitution with the amine substrate, thereby leading to a single unsaturated γ- or ε-amino acid derivative.

Injectable extracellular matrix-mimetic hydrogel based on electrospun Janus fibers.

To date, the reported injectable hydrogels have failed to mimic the fibrous architecture of the extracellular matrix (ECM), limiting their biological effects on cell growth and phenotype. Additionally, they lack the micro-sized pores present within the ECM, which is unfavorable for the facile transport of nutrients and waste. Herein, an injectable ECM-mimetic hydrogel (IEMH) was fabricated by shortening and dispersing Janus fibers capable of self-curling at body temperature into pH 7.

Stimuli-responsive rotaxane-branched dendronized polymers with tunable thermal and rheological properties.

Aiming at the creation of polymers with attractive dynamic properties, herein, rotaxane-branched dendronized polymers (DPs) with rotaxane-branched dendrons attached onto the polymer chains are proposed. Starting from macromonomers with both rotaxane-branched dendrons and polymerization site, targeted rotaxane-branched DPs are successfully synthesized through ring-opening metathesis polymerization (ROMP). Interestingly, due to the existence of multiple switchable [2]rotaxane branches within the attached dendrons, anion-induced reversible thickness modulation of the resultant rotaxane-branched DPs is achieved, which further lead to tunable thermal and rheological properties, making them attractive platform for the construction of smart polymeric materials.

Potential therapeutic target of EGF on bile duct ligation model and biliary atresia children.

Background: The pathogenesis of liver fibrosis in biliary atresia (BA) is unclear. Epidermal growth factor (EGF) plays a vital role in liver fibrosis. This study aims to investigate the expression of EGF and the mechanisms of its pro-fibrotic effects in BA.

Photoredox-Catalyzed Carbonyl Alkylative Amination with Diazo Compounds: A Three-Component Reaction for the Construction of γ-Amino Acid Derivatives.

A photoredox-catalyzed reaction of secondary amines, aldehydes, diazo compounds, and Hantzsch ester is reported, affording biologically active γ-amino acid derivatives in high yields. This one-pot process tolerates a broad range of functional groups and various drug molecules and biologically active compounds. Remarkably, a gram-scale reaction and diverse transformations of γ-amino acid derivatives were successfully performed, and the utility of the products is demonstrated in the synthesis of therapeutic agent pregabalin.

Sweat-Resistant Silk Fibroin-Based Double Network Hydrogel Adhesives.

The adhesion between flexible epidermal sensors and human skin is essential for maintaining the stable functionality of the sensors. However, it is still challenging for epidermal electronic devices to achieve durable adhesion to the surface of the skin, especially under sweaty or humid conditions. Here, we report a silk fibroin-polyacrylamide (SF-PAAm) double network (DN) hydrogel adhesive with excellent biocompatibility, strong and durable adhesion on wet surfaces, and tunable adhesive properties.

MiRNA-4537 functions as a tumor suppressor in gastric cancer and increases the radiosensitivity of gastric cancer cells.

Radiotherapy is a common method to treat gastric cancer (GC). However, the clinical outcomes of GC radiotherapy face challenges, and the mechanisms of GC radioresistance remain unclear. Our study aimed to investigate the role and mechanism of miR-4537 in the radiation sensitivity of GC cells.

The favorable prognosis of cystic biliary atresia may be related to early surgery and mild liver pathological changes.

Objective: The objectives of this study is to compare the prognostic differences between cystic biliary atresia (CBA) and non-CBA, analyze the clinical and liver pathological differences between the two groups, and explore the possible factors that affect the native liver survival of infants with CBA after Kasai portoenterostomy (KPE).

Methods: From 2013 to 2020, 131 infants with BA were admitted to Tianjin Children's Hospital. A total of 108 infants with BA were included after excluding those who did not undergo surgery after diagnosis (n = 23), including 12 cases of CBA and 96 cases of non-CBA.

Prognosis of Biliary Atresia Associated With Cytomegalovirus: A Meta-Analysis.

The etiology of biliary atresia is unclear, but viral infection has been implicated. The aim of the current meta-analysis was to investigate relationships between cytomegalovirus (CMV) and the prognosis of biliary atresia. PubMed, Embase, the Cochrane Library, the China National Knowledge Infrastructure database, and Wanfang Data electronic databases were searched for eligible studies.

Radical-Mediated Strategies for the Functionalization of Alkenes with Diazo Compounds.

One of the most common reactions of diazo compounds with alkenes is cyclopropanation, which occurs through metal carbene or free carbene intermediates. Alternative functionalization of alkenes with diazo compounds is limited, and a methodology for the addition of the elements of Z-CHR (with Z = H or heteroatom, and CHR originates from N═CR) across a carbon-carbon double bond has not been reported. Here we report a novel reaction of diazo compounds utilizing a radical-mediated addition strategy to achieve difunctionalization of diverse alkenes.

Lasso Proteins: Modular Design, Cellular Synthesis, and Topological Transformation.

Entangled proteins have attracted significant research interest. Herein, we report the first rationally designed lasso proteins, or protein [1]rotaxanes, by using a p53dim-entwined dimer for intramolecular entanglement and a SpyTag-SpyCatcher reaction for side-chain ring closure. The lasso structures were confirmed by proteolytic digestion, mutation, NMR spectrometry, and controlled ligation.

A gold(i)-catalysed chemoselective three-component reaction between phenols, α-diazocarbonyl compounds and allenamides.

Gold(i) catalysts are considered to be efficient in promoting sp C-H bond insertion at the para position of unprotected phenols because of the exceptionally chemical reactivity of gold-stabilized carbophilic carbocations. Herein, we present a gold(i)-catalysed three-component reaction between phenols, diazocarbonyl compounds and allenamides, affording the corresponding three-component reaction products with excellent geometric selectivity (E : Z > 20 : 1) in moderate to high yields (up to 90%) under mild conditions. Additionally, a gram-scale transformation and diverse transformations of the resulting product show the high synthetic utility of the present three-component protocol.

A gold(i)-catalysed three-component reaction via trapping oxonium ylides with allenamides.

A gold(i)-catalysed three-component reaction between alcohols (and water), α-aryl-α-diazoesters and allenamides has been developed, affording three-component products, tert-allylic ethers (and alcohols), in moderate to excellent yields with excellent geometric selectivity (E : Z > 20 : 1). In addition, this transformation proceeds smoothly with high functional group tolerance and a broad substrate scope under exceptionally mild reaction conditions. Remarkably, a gram-scale reaction is also successfully performed, and the corresponding three-component product can readily react with easily obtained reagents, furnishing diverse products in satisfactory yields.

Transition Kinetics of Self-Assembled Supramolecular Dodecagonal Quasicrystal and Frank-Kasper σ Phases in AB Dendron-Like Giant Molecules.

A series of noncrystalline AB dendron-like giant molecules DPOSS-MPOSS ( = 2-6, DPOSS: hydrophilic polyhedral oligomeric silsesquioxane (POSS) cage; MPOSS: hydrophobic POSS cage) were synthesized. These samples present a thermodynamically stable phase formation sequence from the hexagonal cylinder phase (plane group of 6), to the Frank-Kasper (F-K) A15 phase (space group of 3̅), and further to the F-K σ phase (space group of 4/), with increasing the number of MPOSS in a single molecule (, from 2 to 6). Moreover, for DPOSS-MPOSS and DPOSS-MPOSS, an intriguing dodecagonal quasicrystal (DQC) structure has been identified and revealed as a kinetic favorable metastable phase at lower temperatures, while the thermodynamically stable phase is the σ phase.

Asymmetric Multicomponent Reactions for Efficient Construction of Homopropargyl Amine Carboxylic Esters.

Developing an efficient and highly enantioselective protocol to access homopropargyl amines is of high interest to the synthetic community and also remains a formidable challenge for organic chemists. Here, we present integrated Rh(OAc)- and BINOL-derived chiral phosphoric acid cooperatively catalyzed three-component reactions of alkynyldiazoacetates, imines with various nucleophiles including alcohols, indoles, and N,N-disubstituted anilines, affording the corresponding homopropargyl amines containing two vicinal chiral centers in satisfactory yields with high to excellent diastereo- and enantioselectivities.

Correction: Finite cohesion due to chain entanglement in polymer melts.

Correction for 'Finite cohesion due to chain entanglement in polymer melts' by Shiwang Cheng et al., Soft Matter, 2016, 12, 3340-3351.

Relationship between Tissue Distributions of Modified Wuzi Yanzong Prescription () in Rats and Meridian Tropism Theory.

Objective: To investigate the relationship between tissue distributions of modified Wuzi Yanzong prescription (, MWP) in rats and meridian tropism theory.

Methods: A high-performance liquid chromatography with Fourier transform-mass spectrometry (HPLC-FT) method was used to identify the metabolites of MWP in different tissues of rats after continued oral administration of MWP for 7 days. The relationship between MWP and meridian tropism theory was studied according to the tissue distributions of the metabolites of MWP in rats and the relevant literature.

Finite cohesion due to chain entanglement in polymer melts.

Three different types of experiments, quiescent stress relaxation, delayed rate-switching during stress relaxation, and elastic recovery after step strain, are carried out in this work to elucidate the existence of a finite cohesion barrier against free chain retraction in entangled polymers. Our experiments show that there is little hastened stress relaxation from step-wise shear up to γ = 0.7 and step-wise extension up to the stretching ratio λ = 1.

[Study of effect of Humifuse Euphorbia Herb on alleviating insulin resistance in type 2 diabetic model KK-Ay mice].

[To explore the effect of Humifuse Euphorbia Herb ( HEH) on alleviating insulin resistance in type 2 diabetic KK-Ay mice. Totally 40 KK-Ay mice fed with high-fat diet were divided into four groups: the metformin group, the model group, the HEH low-dose group and the HEH high-dose group, and orally administrated with metformin hydrochloride (250 mg x kg(-1)), distilled water, humifuse euphorbia herb 1 g x kg(-1) and 2 g x kg(-1). Besides, C57BL/6J mice with ordinary feed were taken as the normal control group and orally administrated with equal distilled water.

Design, synthesis and biological activity of aromatic diketone derivatives as HIV-1 integrase inhibitors.

A series of aromatic diketone derivatives were designed and synthesized as potential HIV-1 integrase (IN) inhibitors and evaluated to determine their ability to inhibit the strand transfer process of HIV-1 integrase. The results indicate that (Z)-1-(3-acetyl-2-hydroxy-4,6-dimethoxyphenyl)-3-hydroxy-3-(substituted)phenylprop-2-en-1-one (5a-5d) can moderately inhibit HIV-1 integrase. The cyclization and condensation products (6a-6c and 7e-7f) of compounds 5a-5d show poor inhibitory activity against HIV-1 integrase.

Strain hardening in startup shear of long-chain branched polymer solutions.

We show for the first time that entangled polymeric liquids containing long-chain branching can exhibit strain hardening upon startup shear. As the significant long-chain branching impedes chain disentanglement, Gaussian coils between entanglements can deform to reach the finite extensibility limit where the intrachain retraction force exceeds the value expected from the usual conformational entropy loss evaluated based on Gaussian chain statistics. The phenomenon is expected to lead to further theoretical understanding.

Splenic marginal zone lymphoma: a population-based study on the 2001-2008 incidence and survival in the United States.

The epidemiology of splenic marginal zone lymphoma (SMZL) in the United States has not been addressed. Eight years of data (2001-2008) from 17 registries of the Surveillance, Epidemiology and End Results (SEER) program were used for this study. Of the 116,411 cases of non-Hodgkin lymphoma (NHL) in the registries, 763 (0.

Schisandrin B exerts anti-neuroinflammatory activity by inhibiting the Toll-like receptor 4-dependent MyD88/IKK/NF-κB signaling pathway in lipopolysaccharide-induced microglia.

Microglial-mediated neuroinflammation is now considered to be central to the pathogenesis of various neurodegenerative processes, including Alzheimer's disease and Parkinson's disease. Therefore, rational modulation of microglia function to obtain neuroprotective effects is important for the development of safe and effective anti-inflammatory and neuroprotective agents. Here, we investigated the anti-inflammatory and neuroprotective effects, and potential molecular mechanism of action of Schisandrin B (Sch B); which is isolated from the Schizandra fruit (Schisandra chinesnesis).