(E)-Ethyl 2-cyano-3-(3,4-dihydr­oxy-5-nitro­phen­yl)acrylate

The title compound, C12H10N2O6, was synthesized via a Knoevenagel condensation and crystallized from ethanol. In the crystal, strong classical inter­molecular O—H⋯O hydrogen bonds and weak C—H⋯N contacts link the mol­ecules into ribbons extending along [010]. Intra­molecular O—H⋯O and C—H⋯N contacts support the planar conformation of the mol­ecules (mean deivation 0.0270 Å)

Cryptochrome Magnetoreception Mechanism Indicates a New Kind of Magnetometer

Cryptochrome, a blue-light photoreceptor which has high sequence homology to DNA photolyase, is supposed to be the most conceivable magnetoreceptor in avian’s magnetoreception. Its light-response mechanism is proposed to result from photoreduction of a protein-bound flavin chromophore through intramolecular electron transfer. We review the cryptochrome magentoreception focusing on the radical pair mechanism, structure of cryptochromes, theoretical and behavioral evidences and the electron transfer models inner cryptochrome protein. Finally, we analysis the superiority of avian’s magnetosensitivity and point out that the animal’s genius radical pair mechanism may be simulated to develop a new chemical magnetic detection mechanism, or even a new kind of magnetometer, which is different from current magnetic detection technology. Keywords: cryptochrome; radical pair mechanism; signaling pathway; electron transfe

Inhibition of proliferation, migration and invasion of human non-small cell lung cancer cell line A549 by phlomisoside F from Phlomis younghusbandii Mukerjee

Purpose: To determine the effect of phlomisoside F (PMF) on the proliferation,  migration and invasion of human non-small cell lung cancer cell line A549 and explore the possible mechanisms.Methods: The anti-proliferative effect of PMF on A549 cells was determined by CCK-8. Subsequently, migration and invasion were evaluated by Transwell and Transwell with matrigel assays, respectively. Furthermore, cell cycle and apoptosis were assessed by flow cytometry, while the mechanisms of action were determined by Western blotting.Results: PMF exhibited significant anti-proliferative effect on A549 cells in  concentration-dependent and time-dependent manners, with half maximal inhibitory concentration (IC50) of 54.51 μM. Treatment with PMF (10, 20 and 40 μM) for 48 h resulted in significantly decreased migration and invasion in A549 cells. In addition, PMF at concentrations of 25, 50 and 75 μM induced cell cycle arrest in  G0/G1phase and enhanced cell apoptosis in A549 cells. Furthermore, caspase-3, caspase-9 and Bax protein expressions were up-regulated while Bacl-2 and COX-2 protein expressions were significantly downregulated at 10, 20 and 40 μM concentrations of PMF.Conclusion: PMF suppresses A549 cell growth, migration and invasion. The  mechanism may be related to the induction of mitochondria-mediated apoptosis pathway via regulation of caspase-3, caspase-9, Bcl-2 and Bax expressions, and inhibition of PGE2 synthesis by reducing COX-2 expression.Keywords: Phlomisoside F, Lung cancer, Cell mobility, Apoptosis, PGE2, COX-2 expression, Caspase, Cell cycle arres

1,1′-[o-Phenyl­enebis(nitrilo­methyl­idyne)]di-2-naphthol ethanol hemisolvate

The asymmetric unit of the title compound, C28H20N2O2·0.5C2H5OH, contains two independent mol­ecules of 1,1′-[o-phenyl­enebis(nitrilo­methyl­idyne)]di-2-naphthol, denoted A and B, and one ethanol solvent mol­ecule. The hydr­oxy groups are involved in intra­molecular O—H⋯N hydrogen bonds influencing the mol­ecular conformations, which are slightly different in mol­ecules A and B, where the two bicyclic systems form dihedral angles of 51.93 (9) and 58.52 (9)°, respectively. In the crystal structure, a number of short inter­molecular C⋯C contacts with distances of less than 3.5 Å suggest the existence of π–π inter­actions, which contribute to the stability of the crystal packing

Transcriptome-based Discovery of AP2/ERF Transcription Factors Related to Terpene Trilactones Synthesis in Ginkgo biloba

Ginkgo biloba is a unique tree in China with medicinally and phylogenetically important characteristics. Terpene trilactones (TTL) is a key active pharmaceutical ingredient in Ginkgo, so the content of TTL in Ginkgo has become one of the important indices for evaluating quality of the medicinal materials. By transcriptome sequencing on samples treated by chlormequat, ultraviolet (UV) and drought, totally 59820 contigs and 37564 unigenes were obtained. Furthermore, 18234 unigenes were annotated through COG, KEGG and GO analysis. There were 78 AP2/ERF transcription factors, 23 factors of up-regulation and 66 factors of down-regulation that were related with synthetic pathway of TTL in Ginkgo. Phylogenetic tree clustering analysis indicated that there were 42 AP2s could be clustered into ERF, DREB and RVA subfamilies. EMSA analysis demonstrated that GbERF13, GbERF25 and GbERF27 could bind with regulatory elements, such as E-box, in the upstream of GbMECPs promoter. Expression analysis showed that the expression level of GbERF25 was the highest in root, and GbERF25 and GbERF27 were expressed in relatively high transcription levels in leaf and other tissues. The results of qRT-PCR indicated that CCC treatment could significantly improve expression levels of ERF25 and ERF27, and UV and drought could induce transcription levels of ERF13 and ERF25, respectively. The results implied that ERF25 and ERF27 might involve in the induction and regulation of CCC treatment on synthesis of bilobalide in G. biloba. ERF13 might participate in the regulation of bilobalide synthesis induced by UV, and EFR25 might involve in the regulation of the synthesis induced by drought. During annual cycle of expression, the transcription levels of ERF13, ERF25 and ERF27 had significantly positive correlation with diterpene level with correlation coefficient 0.975. It implied that these transcription factors mainly acted on the MEP pathway that regulated synthesis of bilobalide. The aim of the research was to indicate the mechanism of environment or cultivation measure regulating target gene of TTL metabolic pathway by AP2/ERF, and establish metabolic network of AP2/ERF regulating TTL synthesis

Modulating Linker Composition of Haptens Resulted in Improved Immunoassay for Histamine.

Histamine (HA) is an important food contaminant generated during food fermentation or spoilage. However, an immunoassay for direct (derivatization free) determination of HA has rarely been reported due to its small size to induce the desired antibodies by its current hapten-protein conjugates. In this work, despite violating the classical hapten design criteria which recommend introducing a linear aliphatic (phenyl free) linker into the immunizing hapten, a novel haptens, HA-245 designed and synthesized with a phenyl-contained linker, exhibited significantly enhanced immunological properties. Thus, a quality-improved monoclonal antibody (Mab) against HA was elicited by its hapten-carrier conjugates. Then, as the linear aliphatic linker contained haptens, Hapten B was used as linker-heterologous coating haptens to eliminate the recognition of linker antibodies. Indirect competitive ELISA (ic-ELISA) was developed with a 50% inhibition concentration (IC50) of 0.21 mg/L and a limit of detection (LOD) of 0.06 mg/L in buffer solution. The average recoveries of HA from spiked food samples for this ic-ELISA ranged from 84.1% and 108.5%, and the analysis results agreed well with those of referenced LC-MS/MS. This investigation not only realized derivatization-free immunoassay for HA, but also provided a valuable guidance for hapten design and development of immunoassay for small molecules