Photoluminescence Anisotropy in Eutectic Crystals of Polynuclear Lanthanide Complexes and Silver Clusters.

Anisotropy is an intrinsic property of crystalline materials. However, the photoluminescence anisotropy in eutectic crystals of organometallic complexes has remained unexplored. Herein, the eutectic of polynuclear lanthanide complexes and Ag clusters was prepared, and the crystal shows significant photoluminescence anisotropy. The polarization anisotropy of emission δ and degree of excitation polarization P are 2.62 and 0.53, respectively. The rare excitation polarization properties have been proved to be related to the regular arrangement of electric transition dipole moments of luminescent molecules in the crystal. Our design provides a reference for developing new photoluminescence anisotropy materials and expanding their applications.

Integrating network pharmacology and experimental evidence to decipher the cardioprotective mechanism of Yiqihuoxue decoction in rats after myocardial infarction.

ETHNOPHARMACOLOGICAL RELEVANCE: "Qi deficiency and blood stasis" syndrome is one of the most common syndromes treated with Traditional Chinese Medicine among ischemic heart disease (IHD) patients in clinic. As a Chinese herbal formula with the function of tonifying Qi and activating blood, Yiqihuoxue Decoction (YQHX) has been frequently proven to be effective in the clinical treatment of IHD. AIM OF THE STUDY: The cardioprotective mechanisms of YQHX in treating ischemic heart disease were investigated, with emphasis on the key targets and pathways. MATERIALS AND METHODS: In the present study, the potential targets of compounds identified in YQHX were predicted using PharmMapper, Symmap, and STITCH databases, and a "herb-compound-target" network was constructed using Cytoscape. Subsequently, the GO and KEGG functional enrichment analyses were analyzed using the DAVID database. Furthermore, a protein-protein interaction network was constructed using STRING to obtain the key target information. Besides, we used a myocardial ischemia rat model to investigate the cardioprotective effects of YQHX. Transmission electron microscopy and Western blotting were used to observe apoptotic bodies and confirm protein expressions of key candidate targets, respectively. RESULTS: Network pharmacology showed that a total of 141 potential targets were obtained from these databases. The functional analysis results revealed that the targets of YQHX were largely associated with apoptosis, and the PI3K-AKT and MAPK pathways might represent key functional pathways. The hub genes of network include ALB, TP53, AKT1, TNF, VEGFA, EGFR, MAPK1, CASP3, JUN, FN1, MMP9, and MAPK8. In vivo, YQHX significantly improved cardiac function and suppressed apoptosis in ischemic rat myocardium. Furthermore, YQHX could significantly upregulate Nrf2 and HO-1 expression, and inhibit JNK phosphorylation. CONCLUSIONS: Based on network pharmacology and experimental evidence, this study proves that the cardioprotective effects and mechanisms of YQHX depend on multi-component, multi-target, and multi-pathway. In particular, YQHX exerts anti-apoptotic effects potentially by regulating the Nrf2/HO-1 and JNK-MAPK pathways.

Eu2+/Eu3+-Based Smart Duplicate Responsive Stimuli and Time-gated Nanohybrid for Optical Recording and Encryption.

With the rapid development of information science, it is urgent that memory devices possessing high security, density, and desirable storage ability should be developed. In this work, a smart duplicate response of stimuli has been developed and a time-gate nanohybrid based on variable valence Eu2+/Eu3+ coencapsulated has been fabricated and acts as active material in the multilevel and multidimensional memory devices. The luminescence lifetime of Eu3+ in this nanohybrid gave a stimuli response due to which the energy level of the coordinated ligand could be modulated. Furthermore, by a simple sintering procedure, Eu3+ was partially in situ reduced to Eu2+ with a short lifetime in the system. And the in situ reduction ensured both Eu3+ and Eu2+ ions' uniform distribution in the nanohybrid and simultaneous response upon light excitation of variable valence Eu ions. Interestingly, Eu3+ revealed a prolonged lifetime because of the presence of an energy-transfer effect of Eu2+ → Eu3+. Such a nanohybrid had abundant luminescent properties, including the short lifetime of Eu2+, the energy transfer from the Eu2+ to Eu3+ ions, and the stimuli response of the Eu3+ lifetimes when exposed to acidic or basic vapor, thus giving birth to interesting recording and encryption performance in spatial-temporal dimensions. We believe that this research will point out a new direction for the future development of multilevel and multidimensional optical recording and encryption materials.

Induction of MMP­1 and ­3 by cyclical mechanical stretch is mediated by IL­6 in cultured fibroblasts of keratoconus.

In order to understand the effect of mechanical stretch on corneal extracellular matrix remodeling, human keratoconus fibroblasts (HKCFBs) were subjected to cyclic stretch in vitro and the expression of matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMPs), and inflammatory cytokines were evaluated. HKCFBs were seeded into a flexible membrane base and subjected to a cyclic stretch regimen of 10% equibiaxial stretch at a stretching frequency of 1 Hz for 6 h using a Flexcell tension unit. An antibody directed against interleukin­6 (IL­6 Ab) was used to investigate the roles of IL­6 on mechanical stretch mediated regulation of MMP in HKCFBs. Culture supernatants were assayed using an enzyme­linked immunosorbent assay for MMP­1 and ­3, TIMP­1 and ­2, and IL­6. Total RNA from the cells was extracted, and quantitative polymerase chain reaction was used to determine mRNA for MMP­1 and ­3, TIMP­1 and ­2, and IL­6. In stretched cells, levels of MMP­1 and ­3 demonstrated an increase compared with unstretched cells, but levels of TIMP­1, and ­2 revealed a decrease. Mechanical stretch significantly increased the mRNA expression and protein synthesis of IL­6 compared with unstretched cells. IL­6 induced MMP­1 and ­3 expression, whereas no significant effects were observed in levels of TIMP­1 and ­2 compared with the untreated control groups. Additionally, the IL­6 Ab markedly inhibited the stretch­induced increase in MMP­1 and ­3 in culture supernatants in a dose­dependent manner. No significant differences in TIMP­1 and ­2 protein levels were detected between stretched cells treated with IL­6 Ab and stretched cells without IL­6 Ab treatment. These results indicate that cyclical mechanical stretch augments IL­6 production and MMP expression, and reduces levels of TIMP in HKCFBs. Thus, it is suggested that IL­6 mediates the stretch­induced MMP expression.