An ingenious electrochemical system based on naphthalenediimide derivatives for ultrasensitive immunosensing of alpha-fetoprotein.

It is crucial to develop highly efficient electrochemistry systems for sensitive detection of tumour markers. In this work, naphthalenediimide derivatives with electrochemical application potential were successfully synthesized and characterized. Electrochemistry and calculation of density functional theory (DFT) showed that 2,7-bis(4-(dimethylamino)phenyl)benzo[lmn] [3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone (NDI-1) was an ideal candidate for electrochemical probe construction.

Carboxyl hybrid monolithic column in-tube solid-phase microextraction coupled with UPLC-QTRAP MS/MS for the determination of amphetamine-type stimulants.

A carboxyl functionalized organic-inorganic hybrid monolithic column (TMOS-co-CES) was applied as in-tube solid-phase microextraction (SPME) sorbent combining with ultra-performance liquid chromatography-triple quadrupole/linear ion trap mass spectrometer for separation and analyzation of seven typical amphetamine-type stimulants (ATSs), including amphetamine (AM), methamphetamine (MAM), cathinone, methcathinone, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine and 3,4-methylenedioxyethylamphetamine. The application potential of TMOS-co-CES material to ATSs was preliminarily confirmed by computational simulation by using cathinone as a representative. The influences of various SPME parameters and analytical performance were investigated systematically.

Aptamer based hybrid monolithic pipette tips supported by melamine sponge for enrichment of proteins.

Background: The convenient preparation and application of functionalized organic-inorganic hybrid monolithic materials have obtained substantial interest in the pretreatment of complex samples by solid-phase extraction (SPE). Compared to the in-tube solid-phase microextraction in fused-silica capillaries, micro SPE in plastic pipette tips have fascinating merits for the easily operated enrichment of trace target analytes from biological samples. However, the poor compatibility of organic-inorganic hybrid monoliths with plastics leads to the rare appearance of commercial hybrid monolithic pipette tips (HMPTs).

Quantitative determination of amphetamine-type stimulants in sewage and urine by hybrid monolithic column solid-phase microextraction coupled with UPLC-QTRAP MS/MS.

A needle-solid-phase microextraction (SPME) method based on hybrid monolithic column (HMC) was proposed for simultaneous separation and extraction of seven amphetamine-type stimulants (ATSs) (amphetamine, methamphetamine, cathinone, methcathinone, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, and 3,4-methylenedioxyethylamphetamine), combining with ultra-performance liquid chromatography-triple quadrupole/linear ion trap mass spectrometer (UPLC-QTRAP MS/MS). Thiol functionalized HMC (T-HMC) showed high extraction efficiency and excellent elution results towards target analytes, among three kinds of single/bi-functionalized HMCs. Various parameters of SPME operation and analytical performance were investigated systematically.

[Biological characteristics of heat shock transcription factors and their roles in abiotic stress adaptation of higher plant].

Heat shock transcription factors (HSFs) are involved in the regulation of plant growth and development. Furthermore, HSFs regulate the expression of a series of genes related to various abiotic stress adaptations. HSFs usually form homotrimers to activate their transcriptional activity and function.

Universal gold nanoparticle modified hybrid monolithic substrate developed for facile in-column post-functionalization.

Organic-inorganic hybrid monolithic columns, due to the comprehensive advantages, have been applied as promising solid-phase separation matrices for pretreatment of complex samples in biomedical and environmental analyses, however, a tremendous time and efforts are cost to optimize the preparation methods of hybrid monolithic columns with different functional groups for various target analytes. Herein, we proposed a strategy to develop basic hybrid monolithic column materials for flexible and facile post-functionalization. Three kinds of single-functionalized (amine, thiol, and carboxyl) and two kinds of bi-functionalized (amine and thiol, and amine and carboxyl) hybrid monolithic columns were immobilized with gold nanoparticles (GNPs) as intermediary bridge to construct the universal substrates.

Carboxyl-functionalized hybrid monolithic column prepared by "thiol-ene" click reaction for noninvasive speciation analysis of chromium with inductively coupled plasma-mass spectrometry.

A novel carboxyl-functionalized hybrid monolithic column was developed based on "thiol-ene" click reaction via "one-pot" by choosing mercaptosuccinic acid, γ-methyl methacrylate trimethoxysilane and tetramethoxysilane as reaction monomers. The design of the hybrid monolithic column was assisted by the comparison in computational simulation with existing carboxyl-functionalized materials. The characterization by scanning electron microscopy, energy dispersive X-ray spectroscopy, N adsorption-desorption measurement, Fourier-transform infrared spectroscopy and elemental analysis showed that the carboxyl-functionalized material has the advantages of good permeability and high mechanical strength.

MicroRNA-1269 promotes cell proliferation via the AKT signaling pathway by targeting RASSF9 in human gastric cancer.

Background: MicroRNAs (miRNAs) play key roles in tumorigenesis and progression of gastric cancer (GC). miR-1269 has been reported to be upregulated in several cancers and plays a crucial role in carcinogenesis and cancer progression. However, the biological function of miR-1269 in human GC and its mechanism remain unclear and need to be further elucidated.

Speciation analysis of chromium by carboxylic group functionalized mesoporous silica with inductively coupled plasma mass spectrometry.

Carboxyl-group functionalized mesoporous silica (CFMS) prepared by one-pot co-condensation method was employed for the solid phase extraction (SPE) of chromium species for the first time. A new approach of SPE coupled to inductively coupled plasma mass spectrometry (ICP-MS) was thus established for the speciation of chromium in environmental water samples. The influences of pH, volume of sample, extraction time, amount of adsorbent, elution conditions, co-existing ions and adsorption capacity were investigated on adsorption or elution of chromium species.

MicroRNA-770 affects proliferation and cell cycle transition by directly targeting CDK8 in glioma.

Background: MicroRNAs play crucial roles in tumorigenesis and tumor progression. miR-770 has been reported to be downregulated in several cancers and affects cancer cell proliferation, apoptosis, metastasis and drug resistance. However, the role and underlying molecular mechanism of miR-770 in human glioma remain unknown and need to be further elucidated.

Preparation and analytical application of novel thiol-functionalized solid extraction matrices: From mesoporous silica to hybrid monolithic capillary column.

A comprehensively comparative study of thiol-functionalized mesoporous silica and organic-inorganic hybrid monolithic column was reported, aiming at the separation and enrichment of inorganic arsenic. Thiol-functionalized mesoporous silica was synthesized based on the one-step co-condensation method. At the same time, a novel thiol-functionalized organic-inorganic hybrid monolithic column was synthesized using an unconventional ternary weak basic solvent system via one-step sol-gel process.

Design and Synthesis of Chiral oxa-Spirocyclic Ligands for Ir-Catalyzed Direct Asymmetric Reduction of Bringmann's Lactones with Molecular H.

We herein present a facile and column-free synthetic route toward a structurally unique oxa-spirocyclic diphenol, termed as O-SPINOL. Features of the synthesis include the construction of the all-carbon quaternary center at an early stage, a key double intramolecular SAr step to introduce the spirocycles and the feasibility of operating on >100 g scale. Both enantiomers of O-SPINOL can be easily accessed through optical resolution with l-proline by control of the solvent.

Preparation of an aptamer based organic-inorganic hybrid monolithic column with gold nanoparticles as an intermediary for the enrichment of proteins.

A novel strategy for the preparation of an aptamer based organic-inorganic hybrid affinity monolithic column was developed successfully using gold nanoparticles (GNPs) as an intermediary for a sandwich structure to realize the functional modification of the surface of the monolithic matrix. This monolithic matrix was facilely pre-synthesized via one-step co-condensation. Due to the high surface-to-volume ratio of GNPs and the large specific surface area of the hybrid matrix, the average coverage density of aptamers on the hybrid monolith reached 342 pmol μL(-1).

MicroRNA-25 Negatively Regulates Cerebral Ischemia/Reperfusion Injury-Induced Cell Apoptosis Through Fas/FasL Pathway.

MicroRNA-25 (miR-25) has been reported to be a major miRNA marker in neural cells and is strongly expressed in ischemic brain tissues. However, the precise mechanism and effect of miR-25 in cerebral ischemia/reperfusion (I/R) injury needs further investigations. In the present study, the oxygen-glucose deprivation (OGD) model was constructed in human SH-SY5Y and IMR-32 cells to mimic I/R injury and to evaluate the role of miR-25 in regulating OGD/reperfusion (OGDR)-induced cell apoptosis.

Silencing of polo-like kinase 2 increases cell proliferation and decreases apoptosis in SGC-7901 gastric cancer cells.

Polo‑like kinase 2 (PLK2) is a serine/threonine protein kinase, which has vital roles during mitosis and the centrosome cycle. In acute myeloblastic leukemia and hepatocarcinogenesis, PLK2 acts as a tumor suppressor; however, the function of PLK2 in gastric cancer remains to be elucidated. In the present study, PLK2 was overexpressed in gastric cancer tissues and three types of gastric cancer cells, SGC‑7901, MKN‑45 and BGC‑823.

Proteomic Profiling of Invasive Ductal Carcinoma (IDC) using Magnetic Beads-based Serum Fractionation and MALDI-TOF MS.

Aim: To reveal the serum proteomic profiling of intraductal carcinoma (IDC) patients in China, establish a serum proteome fractionation technique for choosing magnetic beads for proteomic analysis in breast cancer research; and identify differentially expressed peptides (m/z; P < 0.0001) as potential biomarkers of early IDCs.

Methods: We used two different kinds of magnetic beads (magnetic bead-based weak cation exchange chromatography (MB-WCX) and immobilized metal ion affinity chromatography (MB-IMAC-Cu)) to analyze 32 patients with early stage (stages I-II) IDC and 32 healthy control serum samples for proteomic profiling by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis.

miR-638 suppresses cell proliferation in gastric cancer by targeting Sp2.

Background: MicroRNAs play important roles in the development and progression of various cancers. Recent studies have shown that miR-638 was downregulated in several tumors; however, its role in gastric cancer (GC) has not been investigated in detail.

Aims: The purpose of this study was to determine the role of miR-638 and to elucidate its regulatory mechanism in GC.