In this study, a novel Schiff base of melamine used as flame-retardant curing agent for epoxy resins, was synthesized via condensation reaction of 4-hydroxybenzaldehyde with melamine, followed by the addition of 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) to the resulting imine linkage. The structure of DOPO-containing melamine Schiff base (P-MSB) was characterized by Fourier transformed infrared spectroscopy, 1 H-nuclear magnetic resonance ( 1 H-NMR) and 31 P-NMR. The compound (P-MSB) was used as a reactive flame retardant in o-cresol formaldehyde novolac epoxy resin (CNE) to prepare flame-retardant epoxy resins for electronic application. The thermal and flame-retardant properties of the epoxy resins cured by various equivalent ratios phenol formaldehyde novolac (PN) and P-MSB were investigated by the nonisothermal differential scanning calorimetry, the thermogravimetric analysis, and limiting oxygen index test. The obtained results showed that the cured epoxy resins possessed high T g (165 C) and good thermal stability (T 5% , 321 C). Moreover, the P-MSB/CNE systems exhibited higher limiting oxygen index (35) and more char was maintained in P-MSB/CNE systems than that in PN/CNE system and the effective synergism of phosphorusnitrogen indicated their excellent flame retardancy.

Endothelial progenitor cells (EPCs) are an important component of stem-cell niches, which are able to promote the self-renewal and pluripotency of mesenchymal stem cells (MSCs). The biological functions of these two cell types is dependent on adhesion, and the adhesion between MSCs and EPCs is important due to their critical role in neovascularization and bone regeneration in tissue engineering. Intercellular adhesion molecule-1 (ICAM-1, also known as cluster of differentiation 54), is a member of the immunoglobulin supergene family, which functions in cell-cell and cell-matrix adhesive interactions. Compared with other adhesion molecules, ICAM-1 is expressed in hematopoietic and nonhematopoietic cells, and can mediate adhesive interactions. The present study aimed to investigate the importance of ICAM-1 in the adhesion of MSCs and EPCs, and demonstrated that adhesion between these cells could be regulated by interleukin (IL)-1β via the p38 mitogen-activated protein kinase pathway. In addition, the results confirmed that ICAM-1 served a critical role in regulation of adhesion between MSCs and EPCs. ELISA, cell immunofluorescence, western blot analysis and adhesion assay were used to confirm our theory from phenomenon to essence. The present study provided evidence to support and explain the adhesion between MSCs and EPCs. Furthermore, the present findings provide a theoretical basis for further stem-cell niche transplantation to increase understanding of the function of MSCs and the crosstalk between MSCs and EPCs in the stem-cell niche.

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Mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs) are attached to each other in the bone marrow (BM) cavity and in in vitro cultures, and this adhesion has important physiological significance. We demonstrated that cell proliferation could be promoted when MSCs were co-cultured with EPCs, which was beneficial to angiogenesis, tissue repair, and regeneration. The adhesion of MSCs and EPCs could promote the pluripotency of MSCs, particularly self-renewal and multi-differentiation to osteoblasts, chondrocytes, and adipocytes. This study focused on the mechanism of adhesion between EPCs and MSCs. The results showed that E-cadherin (E-cad) mediated the adhesion of MSCs and EPCs through the E-cad/beta-catenin signaling pathway. The E-cad of EPCs occupied a dominant position during this process, which activated and up-regulated the beta-catenin (β-catenin) of MSCs to improve cohesion and exert their biological function.

Human hydatid disease (cystic echinococcosis, CE) is a chronic parasitic infection caused by the larval stage of the cestode Echinococcus granulosus. As the disease mainly affects the liver, approximately 70% of all identified CE cases are detected in this organ. Optical molecular imaging (OMI), a noninvasive imaging technique, has never been used in vivo with the specific molecular markers of CE. Thus, we aimed to construct an in vivo fluorescent imaging mouse model of CE to locate and quantify the presence of the parasites within the liver noninvasively. Drug-treated protoscolices were monitored after marking by JC-1 dye in in vitro and in vivo studies. This work describes for the first time the successful construction of an in vivo model of E. granulosus in a small living experimental animal to achieve dynamic monitoring and observation of multiple time points of the infection course. Using this model, we quantified and analyzed labeled protoscolices based on the intensities of their red and green fluorescence. Interestingly, the ratio of red to green fluorescence intensity not only revealed the location of protoscolices but also determined the viability of the parasites in vivo and in vivo tests. The noninvasive imaging model proposed in this work will be further studied for long-term detection and observation and may potentially be widely utilized in susceptibility testing and therapeutic effect evaluation.

Human and animal alveolar echinococcosis (AE) are important helminth infections endemic in wide areas of the Northern hemisphere. Monitoring Echinococcus multilocularis viability and spread using real-time fluorescent imaging in vivo provides a fast method to evaluate the load of parasite. Here, we generated a kind of fluorescent protoscolices in vivo imaging model and utilized this model to assess the activity against E. multilocularis protoscolices of metformin (Met). Results indicated that JC-1 tagged E. multilocularis can be reliably and confidently used to monitor protoscolices in vitro and in vivo. The availability of this transient in vivo fluorescent imaging of E. multilocularis protoscolices constitutes an important step toward the long term bio-imaging research of the AE-infected mouse models. In addition, this will be of great interest for further research on infection strategies and development of drugs and vaccines against E. multilocularis and other cestodes.

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