Preparation of thioglycerol-modified silica through thiol-epoxy click reaction and its application in HILIC for detection of oligosaccharide in beverages.

A novel preparation scheme of thioglycerol-modified silica through thiol-epoxy click reaction was proposed aiming at introducing additional quantities of hydroxyl groups into the structure. When applied as the stationary phase of hydrophilic interaction liquid chromatography (HILIC) for separation of oligosaccharide compounds, the material revealed higher polar separation capability than which synthesized through traditional thiol-ene click reaction. Hydrogen-bond interactions were speculated to be the predominant retention mechanism, while partitioning also participated in the retention of disaccharides and trisaccharides. The column also showed good stability and inter-batch reproducibility. Finally, the column was employed for determination of oligosaccharide compounds in commercial beverages, and good linearities, high accuracy, favorable precision, satisfactory reproducibility and resistance to matrix interference were achieved. In the detection of real samples, the determined content was consistent with the labeled content. This work provided an efficient and practicable method for quantity monitoring of commercial diet drinks in routine laboratory.

ABCB1 1199G>A Polymorphism Affects the Intracellular Accumulation of Antidepressants in LLC-PK1 Recombinant Cell Lines.

ATP-binding cassette, subfamily B, member 1 (ABCB1) transport, or P-glycoprotein (P-gp), is a transport protein that is involved in the absorption and the efflux of some antidepressants, such as selective serotonin reuptake inhibitors. The purpose of the current research was to assess the influence of the ABCB1 1199G>A polymorphism on P-gp-mediated efflux ability toward escitalopram, citalopram, paroxetine, fluoxetine, and sertraline. Two recombinant LLC-PK1 cell systems transfected with ABCB1 1199G and 1199A alleles were constructed. The effects of the 1199G>A polymorphism on P-gp efflux activity toward escitalopram, citalopram, paroxetine, fluoxetine, and sertraline were observed by cytotoxicity, intracellular accumulation, and kinetic tests. The LLC-PK1 cells overexpressing the ABCB1 carrying 1199A allele showed higher resistance to escitalopram (1.92-fold), citalopram (1.68-fold), paroxetine (2.41-fold), and sertraline (1.92-fold) than cells transfected with the 1199G allele (p < 0.01), whereas the two types of recombinant cells displayed a comparable sensitivity to fluoxetine (p > 0.05). The intracellular contents of escitalopram (2.86-fold), citalopram (2.59-fold), paroxetine (2.43-fold), and sertraline (2.36-fold) in cell lines transfected with the 1199A allele were lower than cells overexpressing the 1199G allele (p < 0.01). Moreover, the net efflux ratios of P-gp-mediated escitalopram (2.61-fold), citalopram (2.50-fold), paroxetine (3.17-fold), and sertraline (4.29-fold) in cells overexpressing the 1199A allele were significantly increased compared with cells carrying the 1199G allele (p < 0.01). Nevertheless, overexpression of the variant protein (1199A) had no impact on the transport of fluoxetine. ABCB1 encoded by the 1199A mutant allele transports more efficiently escitalopram, citalopram, paroxetine, and sertraline in comparison to the 1199G wild-type allele. This investigation suggests that the 1199A allele drastically increases the activity of P-gp to drive the transport of escitalopram, citalopram, paroxetine, and sertraline in a substrate-specific manner.

The similarity and variability of the iridoid glycoside profile and antioxidant capacity of aerial and underground parts of Lamiophlomis rotata according to UPLC-TOF-MS and multivariate analyses.

Lamiophlomis rotata (L. rotata) is a Tibetan medicinal herb used for centuries that contains iridoid glycosides (IGs), which are pharmacologically active ingredients and can be used for quality control. The IG profiles of the underground and aerial parts of the plant were determined by UPLC-TOF-MS to evaluate the similarity and variability of the different herbal parts listed in the Chinese Pharmacopoeia. Twenty-six IGs were detected in the total ion current (TIC) profile of L. rotata, and twenty-two of these were identified by comparing the retention times and mass spectra of the compounds to those of authentic standards. Among these compounds, five IGs with the same molecular formula (C17H26O11) were identified for the first time by mass spectrometry based on their different hydroxyl group-substituted positions. The aerial part has a similar chemical profile to that of the roots. The difference between the two parts was determined by multivariate statistical analysis of the UPLC-TOF-MS data of 24 specimens. Sesamoside was explored as the most characteristic marker to distinguish the two parts of L. rotata. To further estimate the distinction between the two parts, the content of total IGs and the antioxidant capacity were investigated in samples from different locations. The aerial parts showed a high content of total IGs and high antioxidant capacity, although not higher than those of the roots. The results also suggest the dosage should be increased when the aerial parts are used as crude medicinal materials instead of the underground parts.

Molecular cloning, characterization and expression of the energy homeostasis-associated gene in piglet.

The energy homeostasis-associated (Enho) gene encodes a secreted protein, adropin, which regulates the expression of hepatic lipogenic genes and adipose tissue peroxisome proliferator-activated receptor γ, a major regulator of lipogenesis. In the present study, the porcine (Sus scrofa) homologue of the Enho gene, which was named pEnho, was amplified by reverse transcriptase polymerase chain reaction (RT-PCR) using oligonucleotide primers derived from in silico sequences. The gene sequence was submitted into the GenBank of NCBI, and the access number is GQ414763. The pEnho encodes a protein of 76 amino acids which shows 75% similarity to Homo sapiens adropin. The expression profile of pEnho in tissues (liver, muscle, anterior jejunum, posterior jejunum, and ileum) was determined by quantitative real-time RT-PCR. pEnho was localized on porcine chromosome 10 and no introns were found. In conclusion, pEnho was cloned and analysed with the aim of increasing knowledge about glucose and lipid metabolism in piglets and helping to promote the health and growth of piglets through adropin regulation.

Photoinduced intramolecular charge transfer and S2 fluorescence in thiophene-pi-conjugated donor-acceptor systems: experimental and TDDFT studies.

Experimental and theoretical methods were used to study newly synthesized thiophene-pi-conjugated donor-acceptor compounds, which were found to exhibit efficient intramolecular charge-transfer emission in polar solvents with relatively large Stokes shifts and strong solvatochromism. To gain insight into the solvatochromic behavior of these compounds, the dependence of the spectra on solvent polarity was studied on the basis of Lippert-Mataga models. We found that intramolecular charge transfer in these donor-acceptor systems is significantly dependent on the electron-withdrawing substituents at the thienyl 2-position. The dependence of the absorption and emission spectra of these compounds in methanol on the concentration of trifluoroacetic acid was used to confirm intramolecular charge-transfer emission. Moreover, the calculated absorption and emission energies, which are in accordance with the experimental values, suggested that fluorescence can be emitted from different geometric conformations. In addition, a novel S(2) fluorescence phenomenon for some of these compounds was also be observed. The fluorescence excitation spectra were used to confirm the S(2) fluorescence. We demonstrate that S(2) fluorescence can be explained by the calculated energy gap between the S(2) and S(1) states of these molecules. Furthermore, nonlinear optical behavior of the thiophene-pi-conjugated compound with diethylcyanomethylphosphonate substituents was predicted in theory.

mu-Oxo-bis{[(6-hydroxymethyl-2-pyridylmethyl)bis(2-pyridylmethyl)amine-kappa)N,N',N'',N''',O]iron(III)} tetrakis(perchlorate).

The novel mu-oxo-diiron complex [Fe2O(BPHPA)2](ClO4)4 [BPHPA is (6-hydroxymethyl-2-pyridylmethyl)bis(2-pyridylmethyl)amine, C19H20N4O], contains a binuclear centrosymmetric [Fe2O(BPHPA)2]4+ cation (the bridging O atom lies on an inversion centre) and four perchlorate anions. Each iron ion is coordinated by four N atoms [Fe-N = 2.117 (5)-2.196 (5) A] and one O atom [Fe-O = 2.052 (5) A] from a BPHPA ligand, and by one bridging oxo atom [Fe-O = 1.7896 (9) A], forming a distorted octahedron. There are hydrogen bonds between the hydroxy group and perchlorate O atoms [O-H...O = 2.654 (7) A].