Visible-Light-Promoted Selenylative Spirocyclization of Indolyl-ynones toward the Formation of 3-Selenospiroindolenine Anticancer Agents.

A metal-free and efficient visible-light-induced spirocyclization of indolyl-ynones with diselenides at room temperature under air atmosphere to prepare 3-selenospiroindolenines in moderate to good yields has been developed. The resulting products were tested for in vitro anticancer activity by MTT assay, and compounds 3 c and 3 e showed potent cancer cell-growth inhibition activities.

A star-shaped molecularly imprinted polymer derived from polyhedral oligomeric silsesquioxanes with improved site accessibility and capacity for enantiomeric separation via capillary electrochromatography.

A star-shaped molecularly imprinted coating was prepared starting from octavinyl-modified polyhedral oligomeric silsesquioxanes (Ov-POSS). It possesses a relatively open structure and has good site accessibility and a larger capacity even at lower cross-linking. The imprinted coating was prepared from S-amlodipine (S-AML) as the template and analyte, Ov-POSS as the cross-linker, and methacrylic acid as the functional monomer. The preparation and chromatographic parameters were optimized, including ratio of template to functional monomer, apparent cross-linking degree, pH value, ACN content and salt concentration in the mobile phase. The best resolution in enantiomer separation by means of capillary electrochromatography reaches a value of 33. A good recognition ability (α = 2.60) was obtained and the column efficiency for S-AML was 54,000 plates m-1. The use of Ov-POSS as a cross-linker significantly improves the column capacity and thus the detection sensitivity. The results show that Ov-POSS is an effective cross-linker for the preparation of imprinted polymers with good accessibility and large capacity. Graphical abstract Schematic presentation of the preparation of star-shaped imprinted polymer using octavinyl-modified polyhedral oligomeric silsesquioxanes (Ov-POSS) and by using methacrylic acid (MAA) as functional monomer. The best enantiometric resolution (33) for amlodipine (AML) can be achieved in capillary chromatography (CEC).

Improving affinity of boronate capillary monolithic column for microextraction of glycoproteins with hydrophilic macromonomer.

A novel boronate affinity monolithic capillary was prepared by in-situ polymerization and successfully applied to microextraction (PMME) of glycoproteins. Using functional monomer 3-(acrylamido)phenylboronic acid (AAPBA) and hydrophilic macromonomer oligo (ethylene glycol) methyl ether methacrylate (OEG), crosslinking monomer ethylene glycol dimethacrylate (EDMA) and binary porogens of n-propanol and 1,4-butanediol, poly(AAPBA-co-OEG-co-EDMA) monolith was made with uniform structure and good column permeability. Systematic optimization of preparation conditions were performed, including AAPBA content, the molar ratio of AAPBA to OEG, crosslinking monomer content, n-propanol content in binary porogens. The optimized OEG boronic monolithic column was characterized with infrared absorption spectroscopy, field emission scanning electron microscopy and N2 adsorption experiment. In this study, extraction performance was tested by PMME of horseradish peroxidase (HRP) and ovalbumin (OVA). Compared with the corresponding OEG-free boronate monolith, the recovery of HRP and OVA was significantly improved to 97.51% and 93.97% (RSDs < 5.0%), respectively, which increased by 30.0%. Moreover, the newly developed monolith was further applied for extraction of HRP and OVA from the egg white samples with the recovery of 96.10% and 92.24% (RSDs < 7.5%), respectively. The results suggested that the introduction of hydrophilic macromonomer into boronic material is an effective method to improve the affinity of boronate affinity chromatography to glycoproteins.

A polymer monolith incorporating stellate mesoporous silica nanospheres for use in capillary electrochromatography and solid phase microextraction of polycyclic aromatic hydrocarbons and organic small molecules.

An inorganic-organic hybrid monolith incorporated with stellated mesoporous silica nanoparticles (SMSNs) was prepared. Using binary solvents, deep eutectic solvents and room temperature ionic liquids, an SMSN-incorporated poly(butyl methacrylate-co-ethylene glycol dimethacrylate) monolith demonstrated uniform structure with good column permeability. A systematic investigation of preparation parameter was performed, including SMSN content, crosslinking monomer content, and the component of binary solvent. The optimized monoliths were characterized by field emission scanning electron microscopy, transmission electron microscopy, area scanning energy dispersive spectrometry, and nitrogen adsorption. Column performance was tested by separating four groups of analytes (alkylbenzenes, anilines, naphthalenes and phenols) by capillary electrochromatography (CEC). Baseline separation of all analytes was obtained with column efficiencies of up to 266,000 plates m-1. The performance of the resulting monolith was further investigated in detail by separating mixtures of polycyclic aromatic hydrocarbons (PAHs), nonsteroidal antiinflammatory drugs (NSAIDs), and hydroxybenzoic acid isomers. Compared with the corresponding SMSN-free monolith, the CEC performance was improved by about six times. Successful extraction of PAHs and quinolones (QNs) were also performed using this capillary. Improved extraction efficiency (20.2%) for complex samples, lake water, was also found when the material was applied to solid phase microextraction of fluoranthene. Graphical abstract A poly(butyl methacrylate-co-ethylene glycol dimethacrylate) monolith incorporated with stellated mesoporous silica nanoparticles was prepared. It demonstrated column efficiency up to 266,000 plates m-1 in capillary electrochromatography and ability as solid phase microextraction for organic small molecules with good column permeability.

[Homoharringtonine combined arsenic trioxide induced apoptosis in human multiple myeloma cell line RPMI 8226: an experimental research].

OBJECTIVE: To clarify the effects and mechanisms of homoharringtonine (HHT) monomer therapy or combination therapy with arsenic trioxide (ATO) on human multiple myeloma (MM) cell line RPMI 8226 in in vitro researches. METHODS: Effects of HHT, ATO, and HHT combined ATO on the growth of MM cell line RPMI 8226 were detected using MTT assay. The morphological changes of cell apoptosis were detected by Hoechst staining. The early apoptosis rate was detected using flow cytometry. Expressions of Caspase-3, Caspase-9, poly-ADP-ribose polymerase (PARP), Bcl-2, Mcl-1, Bcl-xl, and AKT protein were detected by Western blot. RESULTS: HHT and ATO inhibited the proliferation of RPM1 8226 cell line in a time- and dose-dependent manner (P < 0.05). Synergistic effects was shown in the combination group (Cl < 1). HHT and ATO induced the apoptosis of RPMI 8226 in a dose-dependent manner with typical morphological changes of apoptosis and higher early stage apoptosis rate. The enhancement in apoptotic induction was seen when two agents were combined. HHT activated expressions of Caspase-3 and PARP in a dose dependent manner at 24 h. HHT at 40 ng/mL and ATO at 8.5 micromol/L could significantly activate expressions of Caspase-3 and Caspase-9, and down-regulate expressions of anti-apoptotic proteins Bcl-xl and Mcl-1. In addition, the combination therapy of HHT at 40 ng/mL and ATO at 8.5 micromol/L inhibited phosphorylation of AKT in a time-dependent manner. CONCLUSION: HTT, ATO, and combination therapy of HHT and ATO induced the apoptosis of RPMI 8226 cell line possibly through activating Caspase pathways, regulating expressions of Bcl-2 families, and inhibiting phosphorylation of AKT.

[Effects of nitrogen form and its supply position on maize seedling growth under partial root-zone water stress].

A split root system consisting of two compartments was installed to study the effects of nitrogen form and its supply position on the growth of maize seedlings under partial root-zone water stress. Polyethylene glycol (PEG 6000) was added to the nutrient solution in one compartment to simulate partial root-zone water stress, while nitrogen was set as three forms (nitrate nitrogen, ammonium nitrogen, and their 1 : 1 mixture) and supplied to just one compartment (water-stressed or non-water-stressed compartment). Photosynthetic and other physiological indices were examined. Comparing with the nitrogen supplied to water-stressed compartment, the nitrogen supplied to non-water-stressed compartment improved the photosynthetic rate (P(n)), maximum net photosynthetic rate (P(max)), light saturation point (LSP), CO2 saturation point (CSP), chlorophyll content, root activity, nitrogen uptake, and biomass accumulation, but reduced the photorespiration rate (R(p)), CO2 compensation point (CCP), abscisic acid (ABA) concentration in xylem sap, and nitrogen- and water use efficiency of the plants. Supplying nitrate nitrogen or its mixture with ammonium nitrogen improved the P(n), P(max), LSP, CSP, nitrogen uptake, and biomass accumulation, but reduced the CCP, R(p), ABA concentration in xylem sap, and nitrogen- and water use efficiency of the plants, compared with supplying ammonium nitrogen. All the results showed that supplying same nitrogen forms to non-water-stressed compartment was more beneficial to the plant growth but disadvantageous to the plant nitrogen- and water use, compared with supplying the nitrogen forms to water-stressed compartment, and supplying nitrate nitrogen or its mixture with ammonium nitrogen promoted the plant growth but reduced the plant nitrogen- and water use, compared with supplying ammonium nitrogen.