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Both vascular adventitial fibroblasts (VAFs) and urotensin II (UII) play important roles in vascular remodeling diseases, but the mechanism of UII in VAFs is still unclear. UII inhibited miR-124 expression through up-regulating circ0004372 expression, thereby promoting SERTAD4 expression. UII significantly promoted the generation of ROS, MDA and 4-HNE, reduced the activities of SOD, GST and GR, increased Fe2+ concentration and inhibited GPX4 expression through circ0004372/miR-124/SERTAD4. Both UII and ferroptosis inducer Erastin significantly promoted the expression of α-SMA, Collagen I and TGF-β1 in VAFs, but circ0004372 siRNA, miR-124 mimics, SERTAD4 siRNA or Ferrostatin-1 significantly inhibited the effect of UII and Erastin on cell activation. When co-transfected with circ0004372 siRNA and miR-124 inhibitors or miR-124 mimics and SERTAD4 overexpression vector, UII still significantly increased the expression of α-SMA, Collagen I and TGF-β1. After transfection with circ0004372 overexpression vector, miR-124 inhibitors or SERTAD4 overexpression vector and then treating with UII and Ferrostatin-1, the expression of α-SMA, Collagen I and TGF-β1 was still significant; when the circ0004372 overexpression vector and miR-124 mimics or miR-124 inhibitors and SERTAD4 siRNA were co-transfected and then UII and Ferrostatin-1 were added, the expression of α-SMA, Collagen I and TGF-β1 was not significantly increased. Therefore, these results indicate that UII promotes the activation of VAFs through the circ0004372/miR-124/SERTAD4/ferroptosis pathway. [ABSTRACT FROM AUTHOR]

In this paper, a compact microstrip antenna with radiation pattern reconfigurable characteristic employing MEMS switches is proposed and investigated. This novel antenna mainly includes four parts: a circular-shaped patch, six MEMS switches, six fan-shaped coupling cells and six fan-shaped radiation cells. Through controlling the states of MEMS switches, radiation pattern selectivity of the proposed antenna can be achieved. When switching operation states of the antenna from state 1 to state 12 sequentially, the main radiation beam direction in azimuth planes could rotate 30° from 0° to 330° with each switch. Meanwhile, the radiation beam directions in elevation plane and the operation frequencies of the proposed antenna for different operation states are stable at about 35° and 4 GHz, respectively. With the consideration of MEMS switches actual size, the antenna structure and dimensions were optimized and adjusted. The simulated and measured results were analyzed and compared, indicating this compact antenna can be widely used for multifunctional applications and modern wireless communication systems. [ABSTRACT FROM AUTHOR]

Chimaphilin, 2,7-dimethyl-1,4-naphthoquinone, is extracted from pyrola [Passiflora incarnata Fisch.]. In this study, the anticancer activity and underlying mechanisms of chimaphilin toward human breast cancer MCF-7 cells are firstly investigated. Chimaphilin could inhibit the viability of MCF-7 cells in a concentration-dependent manner, and the IC50 value was 43.30 µM for 24 h. Chimaphilin markedly induced apoptosis through the investigation of characteristic apoptotic morphological changes, nuclear DNA fragmentation, annexin V-FITC/propidium iodide (PI) double staining. Flow cytometry assay revealed that chimaphilin triggered a significant generation of ROS and disruption of mitochondrial membrane potential. Additionally, western blotting assay showed that chimaphilin suppressed Bcl-2 level and enhanced Bad level, then activated caspase-9 and caspase-3, and further activated the poly ADP-ribose polymerase (PARP), finally induced cell apoptosis involving the mitochondrial pathway. Furthermore, free radical scavengers N-acetyl-L-cysteine (NAC) pretreatment test testified that chimaphilin could increase the generation of ROS, then induce cell apoptosis. In general, the present results demonstrated that chimaphilin induced apoptosis in human breast cancer MCF-7 cells via a ROS-mediated mitochondrial pathway. [ABSTRACT FROM AUTHOR]