Stromal cell-derived factor 1 (SDF-1) is a critical regulator of endothelial progenitor cells (EPCs) mediated physiological and pathologic angiogenesis. It was considered to act via its unique receptor CXCR4 for a long time. CXCR7 is a second, recently identified receptor for SDF-1, and its role in human EPCs is unclear. In present study, CXCR7 was found to be scarcely expressed on the surface of human EPCs derived from cord blood, but considerable intracellular CXCR7 was detected, which differs from that on EPCs derived from rat bone marrow. CXCR7 failed to support SDF-1 induced human EPCs migration, proliferation, or nitric oxide (NO) production, but mediated human EPCs survival exclusively. Besides that, CXCR7 mediated EPCs tube formation along with CXCR4. Blocking CXCR7 with its antagonist CCX733 impaired SDF-1/CXCR4 induced EPCs adhesion to active HUVECs and trans-endothelial migration. Those results suggested that CXCR7 plays an important role in human cord blood derived EPCs in response to SDF-1.

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TGF-β1, SNAI1 and MMP-9 are implicated in tumor invasion and metastasis. The purpose of this study was to examine TGF-β1, SNAI1 and MMP-9 expression in papillary thyroid carcinoma (PTC), and to assess association of TGF-β1, SNAI1 and MMP-9 expression with several clinicopathological indicators of PTC. TGF-β1, SNAI1 and MMP-9 protein expression in 83 PTCs and their matched normal thyroid specimens were analyzed using immunohistochemistry. The mRNA expression levels of TGF-β1, SNAI1 and MMP-9 in 12 fresh PTC specimens with lymph node metastasis (LNM), 12 fresh PTC specimens without LNM and their matched normal thyroid specimens were assessed by real-time RT-PCR. The results showed that the mRNA and protein expression levels of TGF-β1, SNAI1 and MMP-9 were significantly higher in PTCs than in their matched normal thyroid tissues. There were not significant differences in TGF-β1, SNAI1 and MMP-9 protein expression relative to age, gender, tumor size and TNM stage, except for MMP-9 whose protein expression correlated with tumor size. However, high mRNA and protein expression levels of TGF-β1, SNAI1 and MMP-9 were significantly correlated with LNM. Furthermore, TGF-β1, SNAI1 and MMP-9 protein expression were significantly correlated with one another. Concomitant expression of any two or all of the three molecules had stronger correlation with LNM than did each alone. Collectively, the present results indicate that immunohistochemical and real-time RT-PCR evaluation of TGF-β1, SNAI1 and MMP-9 expression in PTC may be useful to predict the risk of LNM in PTC patients.

Flexible and wearable sensor based on nanocomposite hydrogels has been proposed for monitoring the human large-scale, small-scale movements and several physiological signals. The nanocomposite hydrogel, prepared from graphene oxide (GO), polyvinyl alcohol (PVA) and polydopamine (PDA), exhibits excellent mechanical and electrical properties with tensile stress of 146.5 KPa, fracture strain of 2580%, fracture energy of 2390.86 KJ m−3, and the conductivity of 5 mS cm−1. In addition, it possesses other merits including good self-healing with the electrical self-healing efficiency of 98% of its original resistance within 10 s, and strong self-adhesion onto a variety of surfaces of materials. This self-adhesive, self-healing, graphene-based conductive hydrogel can further assembled as wearable sensors to accurate and real-time detect the signals of human large-scale motions (including bending and stretching fingers joints, wrists joints, elbows joints, neck joints and knees joints) and small-scale motions (including swallowing, breathing and pulsing) through fracturing and recombination of reduced graphene oxide (rGO) electrical pathways in porous structures of hydrogel networks. Furthermore, the hydrogel can also be used as self-adhesive surface electrodes to detect human electrophysiological (ECG) signals. Therefore, the hydrogel-based wearable sensor is expected to be used for long-term and continuous monitoring human body motion and detecting physiological parameters.

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