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Abstract: Previously, we reported a missense mutation (C722G) in the M2-muscarinic acetylcholine receptor (CHRM2) gene associated with familial dilated cardiomyopathy. However, the exact molecular mechanisms by the related protein changes of CHRM2-C722G mutation induced are still unclear. CHRM2 and CHRM2-C722G lentiviral vector was infected to CHO cells. Proteomic analysis by label-free shotgun strategy and the STRING 9.0 software were performed. A total of 102 proteins with at least 2-fold change in the CHRM2-C722G group were identified, 42 proteins were up-regulated, whereas 57 were down-regulated. These altered proteins belong to three broad functional categories: (i) metabolic (e.g. Cytosolic acyl coenzyme A thioester hydrolase, Malate dehydrogenase); (ii) cytoskeletal (e.g. Actin-related protein, Myosin light polypeptide 6 and Alpha-actinin-1) and (iii) stress response (e.g. heat shock protein 70, Ras-related protein Rab-10). Interestingly, the marked differences in the expression of selected eight proteins (change >4.0-fold), were connected with many proteins related to apoptosis and immune/inflammatory response such as: FOS, BAX, MYC, TP53 and IL6. This novel study demonstrated for the first time a full-scale screening of the proteomics research by CHRM2-C722G mutation and profiled 102 changed proteins, of which, eight might be critical in cardiac dysfunction for future mapping. Significance: It was a full-scale screening of the proteomics research by CHRM2-C722G mutation. These proteins might serve as valuable biomarkers that could predict the presence of a precursor field. These proteins might serve to further explore the pathophysiological mechanisms in familial DCM patients with C176W mutation. [Copyright &y& Elsevier]

• We developed a novel iron-based metal organic framework (Fe-MOF) with excellent peroxidase-like activity. • The Fe-MOF was designed for detecting F− based on the strong interaction of F− toward Fe3+ and boronic groups of Fe-MOF. • A portable test kit based on the Fe-MOF was constructed for the visual determination of F− by using smartphone. Fluoride ion (F−) is an essential micronutrient in the human body, however, an abnormal large intake of F− can result in adverse effects, such as skeletal fluorosis or DNA damage. Therefore, it is of great significance to develop convenient assays for the visual detection of F− with high sensitivity. We rationally developed the nanosized iron-based metal organic frameworks (Fe-MOFs) by using 3,5-dicarboxybenzeneboronic acid as organic linkers and Fe3+ as metal ions through the solvothermal method, which can be applied for detecting F− with high sensitivity and selectivity owing to the specific recognition of boronic acid groups towards F− and the strong binding affinity between F− and Fe3+. The Fe-MOFs possess excellent peroxidase-like activity, which can be effectively inhibited by F−. Moreover, a portable test kit for the determination of F− was developed by embedding Fe-MOFs into hydrogel, and the visual measurement of F− was realized based on smartphone by identifying the color signal of the oxidation of 3,3',5,5'-tetramethylbenzidine dihydrochloride. The output signal (R/G) was linear with F− concentration in the range of 10.0–200.0 μM. The Fe-MOFs-based colorimetric strategy is easy-operation, low-cost and equipment-free, which has been further applied to detect F− in the real water samples. [ABSTRACT FROM AUTHOR]

Preparation of porous cement-based materials via freeze casting is a process with great potential. However, freeze-drying and steam curing complicate the preparation process and increase the preparation period. To simplify the process, heat-dry curing was used for replacing freeze-drying and steam curing during operation. The new preparation method combined freeze casting and heat-dry curing possesses characteristics of low-energy, simplicity, and time-saving. Compared with the traditional preparation method of porous cement-based materials, the novel preparation process can shorten preparation time by at least 16 % and retrench energy consumption by at least 18 %. As the improvement condition, temperature of heat-drying curing has great influence on the structure and performance of the samples. Therefore, it is of great significance to discuss the relationship between heat-dry temperatures and structural parameters by SEM, N 2 -adsorption/desorption, TG, and ATR-FTIR. Lamellar pores of membranes can be easier observed at low temperatures than that at 100 °C. The separation performance of oil-water is generally improved with the increase of temperature. Meanwhile, the molecular dynamics simulation was operated to illustrate the reaction mechanism of hydration with three temperatures. This study probably provides more theoretical basis for expanding the application of porous silicate cement membranes. [Display omitted] • Novel coupled method simplifies the fabricating process complexity of cement-based samples. • Influences of heat-dry curing temperatures on porous silicate cement membranes are discussed. • Silicate cement membranes own excellent permeation, oil-water separation and mechanical strengths. • Influences of heat-dry curing temperatures are illustrated by using molecular dynamics. [ABSTRACT FROM AUTHOR]

Preparation of porous cement-based materials via freeze casting is a process with great potential. However, freeze-drying and steam curing complicate the preparation process and increase the preparation period. To simplify the process, heat-dry curing was used for replacing freeze-drying and steam curing during operation. The new preparation method combined freeze casting and heat-dry curing possesses characteristics of low-energy, simplicity, and time-saving. Compared with the traditional preparation method of porous cement-based materials, the novel preparation process can shorten preparation time by at least 16 % and retrench energy consumption by at least 18 %. As the improvement condition, temperature of heat-drying curing has great influence on the structure and performance of the samples. Therefore, it is of great significance to discuss the relationship between heat-dry temperatures and structural parameters by SEM, N 2 -adsorption/desorption, TG, and ATR-FTIR. Lamellar pores of membranes can be easier observed at low temperatures than that at 100 °C. The separation performance of oil-water is generally improved with the increase of temperature. Meanwhile, the molecular dynamics simulation was operated to illustrate the reaction mechanism of hydration with three temperatures. This study probably provides more theoretical basis for expanding the application of porous silicate cement membranes. [Display omitted] • Novel coupled method simplifies the fabricating process complexity of cement-based samples. • Influences of heat-dry curing temperatures on porous silicate cement membranes are discussed. • Silicate cement membranes own excellent permeation, oil-water separation and mechanical strengths. • Influences of heat-dry curing temperatures are illustrated by using molecular dynamics. [ABSTRACT FROM AUTHOR]

Abstract: Two rhodamine-based NO probes were designed and synthesized. Both RB-TP and RB-Py can detect NO by spectroscopic and ‘naked-eye’ methods in HEPES buffer assisted by Cu2+. The detection limits for NO were 5 nM and 20 nM, respectively. Other biologically relevant reactive species, such as , H2O2, 1O2, and ClO− did not give any obvious interferences. RB-TP and RB-Py have been also applied to detect the intracellular NO by fluorescence imaging method. [Copyright &y& Elsevier]

One-stage degradation process was observed for a poly(methyl methacrylate) (PMMA) sample. The fractional conversion αmax at the maximum reaction rate is thus applied to determine reaction order of the thermal degradation. It is found that the PMMA degraded in the first order kinetics with weight loss. This is consistent with the fact that PMMA thermally degrades into its monomer. Activation energy was calculated. Compensation effect of the Arrhenius parameters is also found. [Copyright &y& Elsevier]

Abstract: The geometrical structures and electronic properties of six fullerene isomers of C100 were studied at the HF/6-31G⁎ and B3LYP/6-31G⁎ levels, respectively. The results of the fully optimized calculations show that three C100 isomers 449:D2, 425:C1 and 442:C2 are near isoenergetic isomers. The energies and properties of C100 hexaanions were calculated. The C100 6− (450:D5) isomer is predicted to be the most stable isomer at the B3LYP/6-31G⁎ level, and the C100 6− (449:D2) isomer is 44.1kcal/mol higher in energy. The heterofullerenes C96X4 (X=N, P, B, Si) formed from the initial C100 (449:D2) have also been investigated at the B3LYP/6-31G⁎ level. The HOMO–LUMO gaps and aromaticities show that the replacement of fullerene carbon atoms with four heteroatoms can enhance the electronic stabilization of C100 (449:D2). [Copyright &y& Elsevier]

Abstract: The structural and electronic properties of hydrogenated armchair and zigzag SWCNTs with carbon ad-dimer (CD) defect were investigated by means of the B3LYP hybrid density functional method using 6-31G∗ basis set. It is found that the chemisorptions of two hydrogen atoms inside and outside the CD defective SWCNTs are exothermic processes. Exohedral nanotube adsorption is energetically more favorable than endohedral adsorption. These results are in agreement with hydrogen on pristine nanotubes. The positional preference for the chemisorption of two hydrogen atoms is the same for the CD defective armchair and zigzag nanotubes. However, the reaction energy of two hydrogen atoms on the exterior sidewalls of CD defective SWCNTs is almost independent of the tube diameter. This is different from the results reported on pristine nanotubes. The calculated energy gaps indicate that the hydrogen-chemisorbed CD defective armchair tubes are always wide energy gap structures, while the hydrogen-chemisorbed CD defective zigzag tubes have significantly lower gaps. The HOMO–LUMO gap and reaction energy for the chemisorption of more hydrogen atoms on the exterior sidewalls of CD defective armchair SWCNTs were also explored. [ABSTRACT FROM AUTHOR]

Abstract: Based on the recently isolated and characterized nanotube-like D 5 h C90 fullerene, the nonclassical hept-C100 fullerene created by inserting symmetrically five C2 around the circumference of D 5 h C90 and its derivatives C100 X 10 (X =H, F, Cl, and Br) have been reported here. The geometrical structures and electronic properties of them are studied using density functional theory (DFT) at the B3LYP/6-31G∗ level of theory. The reaction energies, HOMO–LUMO gaps, and aromaticities all show that the nonclassical fullerene derivatives C100H10, C100F10, C100Cl10, and C100Br10 are molecules with high stability; the stable behavior resembles the well-known C50 X 10 (X =H, F, Cl, and Br). It is quite possible that they can be synthesized experimentally. [Copyright &y& Elsevier]

Abstract: Ab initio and density functional theory (DFT) methods at the HF/6-31G*, B3LYP/6-31G*, MP2/6-31G*, and MP2/TZVP levels of theory were applied to the investigation of the relative stability of six fullerene isomers of C32. Full geometry optimization of the systems was carried out and electrostatic potential distributions were calculated. The effect of electron correlation on the electrostatic potential distribution of C32 isomers was analyzed. [Copyright &y& Elsevier]

Abstract: Pre-column derivatization allowed stacking amino acid enantiomers on C18 reversed-phase micro extraction columns, thus facilitating sample loading in capillary HPLC/tandem mass spectrometry. Two tagging reagents, i.e. 7-fluoro-4-nitrobenzoxadiazole (NBD-F) and 1-fluoro-2,4-dinitrobenzene (DNB-F) were evaluated. Both of them reacted readily with amino acids at an elevated temperature, resulting in derivatives that were effectively stacked and suitable for a sensitive MS/MS detection as well. Separation of the tagged enantiomers on a teicoplanin chiral stationary phase (CSP) with mobile phases compatible with MS detection was investigated. NBD-amino acid enantiomers (12 pairs) tested were all base-line resolved. However, the efforts to separate DNB-F tagged amino acid enantiomers on this CSP were not successful. Separation conditions including pH, organic modifiers, and column dimension were studied. All the NBD-amino acids studied could be sensitively detected by MS/MS detection set in the negative ion mode, but only a few including NBD-Asp, BND-Glu, NBD-Ser, and NBD-Thr were detected in the positive ion mode. Thus, the selectivity for enantiomeric determination of excitatory amino acids (e.g. Asp and Glu) was further improved by choosing MS/MS detection in the positive ion mode. [Copyright &y& Elsevier]

Enantiomers of clenbuterol were directly separated by a new high performance chromatographic method on Chirex 3005 column. Several parameters such as mobile phase composition, column temperature and flow rate were studied. Baseline enantioseparation was achieved, using the optimized mobile phase of n-hexane–1,2-dicholoethane–methanol (54:38:8, v/v/v) at 17 °C and 1.0 ml/min, with the separation factor (α) 1.43 and the resolution factor (RS) 1.81. The mechanism of separation was also discussed. Standard linear calibration cures were established for the R- and S-enantiomers, over the range of 26.1–1045.8 and 5.7–229.6 nmol/ml, with the correlation coefficient of 0.9999 for both. The limits of detection were 0.47 and 1.04 nmol/ml for R- and S-enantiomers, respectively. Recovery and precision of the method were also evaluated, which had been successfully used to monitor and identify quantitatively the profile of the clenbuterol enantiomers in human serum. [Copyright &y& Elsevier]

In this article, a novel fluorescent probe (NRBE) for detecting H 2 O 2 was developed using benzyl boronic ester as the H 2 O 2 -recognized group and Nile red as the matrix. The probe has several advantages, such as good selectivity, high sensitivity (LOD = 75 nM), good water solubility and emission in the near-infrared region (ex/em:585/670 nm). With the NRBE probe, the endogenous H 2 O 2 in human hepatocellular carcinoma cells BEL-7402, was detected, and the H 2 O 2 generated during the ischemia-reperfusion of the cells was imaged. These results show that NRBE can be applied for real-time detection of H 2 O 2 in biological systems. Unlabelled Image • A novel Nile red-based fluorescent probe NRBE was designed and synthesized for H 2 O 2 detection. • The probe has good selectivity, high sensitivity, good water solubility and emission in the near-infrared region. • The probe can be applied for real-time detection of H 2 O 2 in biological systems. [ABSTRACT FROM AUTHOR]