Programmable mismatch-fueled high-efficiency DNA signal amplifier.

Herein, by introducing mismatches, a high-efficiency mismatch-fueled catalytic multiple-arm DNA junction assembly (M-CMDJA) with high-reactivity and a high-threshold is developed as a programmable DNA signal amplifier for rapid detection and ultrasensitive intracellular imaging of miRNA. Compared with traditional nucleic acid signal amplification (NASA) with a perfect complement, the M-CMDJA possesses larger kinetic and thermodynamic favorability owing to the more negative reaction standard free energy (Δ) as driving force, resulting in much higher efficiency and rates. Once traces of the input initiator react with the mismatched substrate DNA, it could be converted into amounts of output multiple-arm DNA junctions the M-CMDJA as the functional DNA conversion nanodevice.

Green synthesis, crystal structure, and antifungal activities of ()-4-arylidene-5-oxotetrahydrofuran.

A series of γ-lactone derivatives ()-4-arylidene-5-oxotetrahydrofuran derivatives were synthesized a tandem Passerini 3CC/S cyclization microwave-assisted one-pot method efficiently starting from Baylis Hillman acids, aryl glyoxals and isocyanides, and using ionic liquid as reaction medium. The products were characterized by hydrogen nuclear magnetic resonance spectroscopy (H-NMR), carbon nuclear magnetic resonance spectroscopy (C-NMR). Single crystal X-ray analysis of the compound RPDFB clearly confirmed its assigned chemical structures.

Green synthesis, structure optimization and biological evalution of Rhopaladins' analog 2-styryl-5-oxopyrrolidine-2- carboxamide RPDPRH on CaSki cells.

We have synthesized Rhopaladins' analog (2,4)-4-chlorobenzylidene-2-(4-chlorostyryl)--cyclohexyl-1-(4-fluorophenyl)-5-oxopyrrolidine-2-carboxamide (RPDPRH) via a highly facile, inexpensive and green approach and verified the structural superiority of compound RPDPRH through molecular docking. Moreover, we further detected the anti-proliferation, apoptosis and HPV E6/E7 effects of RPDPRH on CaSki cells. Finally, we confirmed that compared with the previous compound ()--(-butyl)-2-(4-chlorobenzoyl)-4-(4-fluorobenzylidene)-1-isopropyl-5-oxopyrrolidine-2-carboxamide (RPDPB), RPDPRH could better inhibit proliferation, induce apoptosis, and down-regulate HPV E6/E7 mRNA expression on Caski cells.

Research Progress on Structure and Anti-Gynecological Malignant Tumor of Shikonin.

Gynecological malignancy seriously threatens the physical and mental health of women. Shikonin is a naphthoquinone compound with a variety of biological activities. Studies have shown that shikonin can inhibit cell proliferation, promote cell apoptosis and induce cell necrosis.

Synthesis and Anticancer Activity of Rhopaladins' Analog RPDPD Against the HeLa Human Cervical Cancer Cell Line.

Heterocyclic compounds were widely used in many domains; pyrrolidone is a derivative of heterocycles that can be used to synthesize anticancer drugs. A new fluorine-containing rhopaladins' analog()-2-(4-bromobenzoyl)--(tert-butyl)-4-(4-fluoro benzylidene)-5-oxo-1-propylpyrrolidine-2-carboxamide (RPDPD for short) of 2-aroyl-4-arylidene-5-oxopyrrolidine derivative was synthesized by the one-pot synthesis method and evaluated for its anti-tumor activity CCK8 assay and annexin V/propidium iodide (PI) staining of HeLa cells. The results exhibited that compound RPDPD has inhibited the proliferation of HeLa in a dose-dependent manner with an IC of 24.

Design, Synthesis, and Apoptosis-Promoting Effect Evaluation of Rhopaladins' Analog 4-Arylidene-5-Oxopyrrolidine Derivatives.

Marine alkaloids have novel structures and antitumor activities. Therefore, we synthesized rhopaladins' analogs from marine alkaloids rhopaladins A-D and modified their structures to synthesize 4-benzylidene-5-pyrrolidone derivatives. Among the compounds, (2, 4)-4-(4-chlorobenzylidene)-2-(4-chlorostyryl)--cyclohexyl-1-(4-fluorophenyl)-5-oxopyrrolidine-2-carboxamide (RPDPRH) has high efficiency and less hepatotoxicity, with IC values of 4.

Programmable High-Speed and Hyper-Efficiency DNA Signal Magnifier.

Herein, a programmable dual-catalyst hairpin assembly (DCHA) for realizing the synchronous recycle of two catalysts is developed, displaying high reaction rate and outstanding conversion efficiency beyond traditional nucleic acid signal amplifications (NASA). Once catalyst I interacts with the catalyst II, the DCHA can be triggered to realize the simultaneous recycle of catalysts I and II to keep the highly concentrated intermediate product duplex I-II instead of the steadily decreased one in typical NASA, which can accomplish in about only 16 min and achieves the outstanding conversion efficiency up to 4.54 × 10 , easily conquering the main predicaments of NASA: time-consuming and low-efficiency.

Dual 3D DNA Nanomachine-Mediated Catalytic Hairpin Assembly for Ultrasensitive Detection of MicroRNA.

Herein, we designed a dual 3D DNA nanomachine (DDNM)-mediated catalytic hairpin assembly (DDNM-CHA) to construct an electrochemical biosensor for ultrasensitive detection of miRNA, which possesses quite a faster reaction rate and much higher amplification efficiency than those of traditional catalytic hairpin assembly (CHA). Impressively, since the DDNM skillfully increases the local concentration of reactants and decreases the steric hindrance of substrates simultaneously, the DDNM-CHA could be endowed with higher collision efficiency and more effective reaction compared with traditional CHA, resulting in a hyper conversion efficiency up to 2.78 × 10 only in 25 min.

Engineering a Rolling-Circle Strand Displacement Amplification Mediated Label-Free Ultrasensitive Electrochemical Biosensing Platform.

In this work, an original rolling-circle strand displacement amplification (RC-SDA) was developed by introducing a circle DNA with two recognition domains as a template instead of the limited liner DNA template in traditional strand displacement amplification (SDA), which displayed much shorter reaction time down to 30 min and quite higher conversion efficiency of more than 1.77 × 10 compared with those of traditional strand displacement amplification (SDA) and could be applied to construct a label-free biosensor for ultrasensitive detection of an HIV DNA fragment. Once the target HIV DNA fragment interacts with the template circle DNA, the RC-SDA could be activated to dramatically output amounts of mimic target DNA with the assistance of the Phi29 DNA polymerase and Nb.

Synthesis and antitumor activity of α,β-unsaturated carbonyl moiety- containing oleanolic acid derivatives targeting PI3K/AKT/mTOR signaling pathway.

Oleanolic acid (OA) and its semi-synthetic derivatives have been reported to have a wide range of biological activities. The introduction of electrophilic Michael acceptor group can increase the reactivity of OA to cellular targets and thus improve the anti-tumor activity. In this work, a series of novel α,β-unsaturated carbonyl derivatives of OA were designed and synthesized.

Improvements in the intraluminal thread technique to induce focal cerebral ischaemia in rabbits.

Although the intraluminal thread technique has been used to induce focal cerebral ischaemia in rabbits, its success rate is not high. We, therefore, attempted to improve the stability and reproducibility of this method by using thread tips of appropriate diameter as determined from the anatomical characteristics of the carotid and cerebral arteries of New Zealand white rabbits. Following intraarterial injection of casting material, we tested threads of four different tip diameters to determine the optimal thread tip that could occlude the middle cerebral artery (MCA).