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A copper-catalyzed regiodivergent hydrosilylation of a wide range of simple allenes is reported. Linear and branched allylsilanes were formed by judicious choice of solvents. Furthermore, branched allylsilanes were obtained with high enantioselectivity (up to 97% enantiomeric excess) with the aid of a C2-symmetric bisphosphine ligand in the unprecedented asymmetric allene hydrosilylation.

A strategically distinct dehydroxylative alkylation reaction of α-hydroxy carboxylic acid derivatives with alkenes is developed. The reaction starts with the attack of a 4-dimethylaminopyridine (DMAP)-boryl radical to the carbonyl oxygen atom, followed by a spin-center shift (SCS) to trigger the C-O bond scission. The resulting α-carbonyl radicals couple with a wide range of alkenes to furnish various alkylated products. This strategy allows for the efficient conversion of a wide array of α-hydroxy amides and esters derived from several biomass molecules and natural products to value-added compounds. Experimental and computational studies verified the reaction mechanism.

Substantial advances in enantioconvergent C(sp3)-C(sp3) bond formation reactions have been made in recent years through the use of transition-metal-catalyzed cross-coupling reactions of racemic secondary alkyl electrophiles with organometallic reagents. Herein, we report a general process for the asymmetric construction of alkyl-alkyl bonds adjacent to heteroatoms, namely, a nickel-catalyzed enantioconvergent reductive hydroalkylation of olefins with α-heteroatom phosphorus or sulfur alkyl electrophiles. Including the use of readily available olefins, this reaction has considerable advantages, such as mild reaction conditions, a broad substrate scope, and good functional group compatibility, making it a desirable alternative to traditional electrophile-nucleophile cross-coupling reactions.

RHBDD1 overexpression is found in various malignancies, including non-small cell lung cancer (NSCLC), and it is correlated with NSCLC patients' poor overall survival. This study aims to explore the function of RHBDD1 in regulating the progression of NSCLC and its potential molecular basis. qPCR, immunohistochemistry, and/or western blotting were used to evaluate the expression of RHBDD1 in NSCLC tissues and cell lines. RHBDD1 knockdown and overexpression were performed, CCK-8 assay and cell clone formation were applied to study the function of RHBDD1 in cell proliferation in vitro. Flow cytometry and immunofluorescence tests were employed to determine the regulation of apoptosis, cell cycle, and endoplasmic reticulum stress by RHBDD1. As a result, RHBDD1 was found significantly upregulated in NSCLC tissues and cells and associated with pathological tumor staging. RHBDD1 knockdown inhibited the proliferation of NSCLC cells both in vitro and in vivo, promoted their apoptosis, caused cell cycle arrest at G0/G1 phase, characterized with reduced CDK2, suppressed TGF-α secretion, and inhibited the EGFR/Raf/MEK/ERK signaling pathway. In contrast, RHBDD1 overexpression showed the opposite effects. These effects of the manipulated expression of RHBDD1 on NSCLC were restored by EGFR or MEK inhibitor. Additionally, RHBDD1 knockdown and overexpression resulted in decreased and increased BIK cleavage, respectively, but the effects could be blocked by a proteasome inhibitor. In conclusion, our research shows that RHBDD1 promotes the progression of NSCLC through enhancement of proliferation and induction of apoptosis by regulating the EGFR/Raf/MEK/ERK signaling pathway and the level of BIK protein level.

In this work, a facile grinding method for preparation of supramolecular square nanoplates formed by β-cyclodextrin and gallium acetylacetonate was developed. The nanoplates exhibited a highly monodispersed distribution nature at room temperature, and were self-assembled to form supramolecular layer nanosheets at 353 K. Heating to higher temperatures such as 673 K led to the decomposition of the layer nanosheets into γ-Ga2O3 layer nanosheets. The γ-Ga2O3 nanosheets (thickness of about 15 nm) with a very high specific surface area (93.9 m2 g−1) show an improved solar-blind detection performance (e.g., light–dark ratio, 1.64 × 104) compared to devices based on 3D structured γ-Ga2O3. We believe that the grinding-heating-strategy provides a convenient and efficient route to synthesize high-quality supramolecular nanocrystals and inorganic nanomaterials.

In this work, a simple one-step hydrothermal method was developed to synthesize high-quality α-Fe2O3 nanoparticles with a snowflake-like microstructure. First, a series of binary supramolecular aggregates were prepared by a non-covalent combination between a polymer such as polyvinylpyrrolidone (PVP) and a complex such as potassium ferrocyanide (PF). Then, the aggregates were used as the precursors of the one-step hydrothermal reactions. The snowflake-like nanostructure has six-fold symmetry as a whole, and each petal is symmetric. This synthesis method has the characteristics of simplicity, rapidity, reliance, and high yield, and can be used for creating high-quality α-Fe2O3 nanoparticles. Moreover, our results show that the molar ratio of PVP to PF, reaction time and temperature play important roles in the generation of a complete snowflake structure from different angles. Also, the snowflake-like α-Fe2O3 nanostructure exhibits a much higher coercivity (2997 Oe) compared to those reported by others, suggesting a strong hysteresis behaviour, which promises potential applications in memory devices, and other fields. Further, the α-Fe2O3 nanosnowflakes show a much higher photocatalytic degradation activity for cationic organic dyes such as crystal violet, rhodamine 6G than for anionic dyes such as methyl orange. A possible photocatalytic mechanism was proposed for explaining the selectivity of the photocatalytic oxidation reaction of organic dyes. We believe that this study provides a direct link among coordination compounds of transition metals, their supramolecular aggregates with polymers, and controlled hydrothermal synthesis of high-quality inorganic metal oxide nanomaterials.

Lung cancer is the most common cause of cancer-associated mortality globally. Long non-coding RNAs (lncRNAs) are transcripts with a length of >200 nucleotides, which are not translated into proteins. Growing evidence has indicated that certain lncRNAs are associated with various biological processes in cancer. However, the functions of KCNK15 and WISP2 antisense RNA 1 (KCNK15-AS1) in lung cancer carcinogenesis and progression have remained elusive. The present study indicated that KCNK15-AS1 was overexpressed in lung adenocarcinoma tissues compared with paracancerous normal tissues, and the high expression of KCNK15-AS1 was significantly associated with poor prognosis compared with the patients with low expression (P

In this work, a simple one-step hydrothermal method was developed to synthesize high-quality α-Fe

Whether dissecting the inferior pulmonary ligaments (IPLs) during superior video-assisted thoracoscopic (VATS) lobectomy for early stage lung cancer remains controversial. This study aimed to evaluate the influence of dissecting the IPLs during VATS superior lobectomy on bronchial distortion and recovery of pulmonary function.This was a retrospective study of 72 patients with non-small cell lung cancer who underwent VATS superior lobectomy from March 2012-August 2013 at the First People's Hospital of Yunnan Province. Patients were grouped according to IPLs preservation (group P) or dissection (group D). The preoperative and postoperative pulmonary function and the postoperative complications were analyzed. The changes in bronchi angles and pulmonary capacity were measured using computed tomography.There were no significant differences in the complication rate and volume of chest drainage between the two groups. The changes in bronchus angle in group P were significantly smaller than those in group D after left lung operation (P = 0.046 at 3 mo; P = 0.038 at 6 mo); in the right lung, the changes were not significant between the two groups (P = 0.057 at 3 mo; P = 0.541 at 6 mo). The forced expiratory volume of 2% and forced expiratory volume in 1 s (FEV1%) were significantly better in group P than those in group D at 3 and 6 mo (P0.05). The pulmonary capacity in group P was significantly larger than that in group D at 6 mo (P = 0.002).Preservation of IPLs during VATS lobectomy might have an impact on the bronchus angle, lung function, and lung volume.

The introduction of a 4-mercaptan substituent was recently reported to be effective to improve the reactivity of C-terminal prolyl thioesters in native chemical ligation (NCL). To elucidate the origin of the high reactivity of 4-mercaptoprolyl thioesters, a theoretical study was performed on the transthioesterification of NCL herein with the aid of density functional theory (DFT) methods. The calculation results support a transthioesterification mechanism involving two stages. The first stage is the intramolecular transthioesterification of 4-mercaptoprolyl thioesters to form a bicyclic thiolactone intermediate and the second stage is the intermolecular transthioesterification of the thiolactone intermediate with N-terminal cysteine. The two stages proceed both via nucleophilic attack of the thiolate and proton-donor-assisted thiolate release. The thiolate release in the first stage is the rate-determining step of the whole transthioesterification of 4-mercaptoprolyl thioesters. Based on the mechanistic details, further analysis was conducted to gain a deeper insight with natural bond orbital (NBO) analysis, non-covalent interaction plots (NCIplots), distortion analysis, etc. The n → π* interaction between the N-carbonyl oxygen and thioester carbonyl was found to be detrimental to the first stage while a previously unnoticed n → π* interaction between the amide nitrogen and the thiolactone carbonyl slightly benefits the second stage. The entropy effect was the main driving force for the first stage because this stage is an intramolecular one-to-two process overall. On the other hand, the release of the ring stain precluded in the bicyclic thiolactone intermediate is mainly responsible for the high reactivity of the thiolactone in the second stage compared with other prolyl thioesters. Meanwhile, the intramolecular hydrogen bond between the thiolactone carbonyl oxygen and the protonated amine of N-terminal cysteine also contributes to the transthioesterification.

In this work, we successfully synthesized ZnGa2O4 microflowers self-assembled by hexagonal single-crystalline nanopetals in a water/ethanol solution through a novel solvothermal route. The self-assembled ZnGa2O4 microflower crystal exhibits improved solar-blind deep ultraviolet detection performance such as short response time, large light to dark current ratio, high photocurrent stability, and good wavelength selectivity under zero bias voltage, with the aid of the formation of heterojunctions with polyvinyl butyral. Our result is not only the best for self-powered solar-blind photodetect devices to date, but also the first report describing the effect of polymer concentrations on photoresponses.