Selective Host-Guest Co-crystallization of Pyridine-Functionalized Tetraphenylethylenes with Phthalic Acids and Multicolor Emission of the Co-crystals.

Tetraphenylethylene (TPE) and its derivatives are the most typical and most widely studied organic compounds showing aggregation-induced emission (AIE). Due to their propeller-like structures, V-like clefts exist between the aryl rings, which make them promising host compounds. However, such a possibility is seldom explored. Herein, it is reported that TPE derivatives bearing two or four pyridine rings at the para positions of the phenyl rings (TPE-Pys) can selectively include triangular (Δ-like) m-phthalic acid from a mixture of o-, m-, and p-phthalic acids due to their shape complementary to form host-guest co-crystals, which showed redder emission than the TPE-Pys themselves. The emission of co-crystals 1-5 could be reversibly switched between yellow and red by alternating exposure to HCl and ammonia vapor. The host-guest co-crystals not only exhibited great potential for selectively recognizing and separating m-phthalic acid and as multicolor emission materials, but are also suitable for use as secret ink due to their reversible color change on varying the host-guest interactions.

Molecular modeling and biological effects of peptidomimetic inhibitors of TACE activity.

We investigated the molecular basis of specificity for the interaction between tumor necrosis factor-alpha converting enzyme (TACE) and peptidomimetic inhibitors. Four novel peptidomimetic TACE inhibitors (8a-d) were designed and synthesized by introducing a substituted sulfur group and a hydrophobic group to a novel matrix metalloprotease (MMP) inhibitor. Inhibition was determined by in vitro lipopolysaccharide (LPS) cytotoxicity tests in HL-60 cell lines and by measuring the expression of mTNF-alpha using FCM techniques and immunohistochemistry in vivo. We simulated the interaction of the inhibitors with the 3D structure of the TACE active site in the Brookhaven Protein Database (PDB). The four inhibitors (8a-d) inhibited activity by 9.1%, 54.5%, 27.3%, and 54.5%, respectively. 8b and 8d showed significant in vitro inhibition in cytotoxicity tests, which corresponded to the molecular docking results. 8d also showed inhibitory activity in vivo. We explored the interface between enzyme and substrate by combining bioinformatics with experimental observations to further the development of specific TACE inhibitors to reduce inflammatory responses.

[The multiplex analysis of epigenetic markers and genetic markers by post-digestion mutagenically separated PCR].

OBJECTIVE: To establish a novel method for the multiplex analysis of the methylation and single nucleotide polymorphism (SNP). METHODS: The imprinted SNP rs220028 was chosen as a model. Genomic DNA, after being digested with methylation sensitive restriction enzyme, were typed by mutagenically separated PCR (MS-PCR). The polymorphism of restriction site was excluded by PCR-RFLP. RESULTS: By post-digestion MS-PCR, the methylated allele was detected selectively, the maternal origin of which was confirmed by pedigree analysis; A=0.5085, G=0.4915,PIC=0.3749. CONCLUSION: The multiplex analysis of methylation markers and SNP can be achieved by post-digestion MS-PCR. The imprinted SNP locus rs220028 is a potentially useful marker in screening Prader-Willi/Angelman syndrome.