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Cobalt chromium (CoCr) alloy is widely used in orthopedic implants but its functional longevity is susceptible to inflammation related complications. Reduction of the development of chronic inflammation on the biomaterial surface would enhance direct bone-implant bonding and improve implant survival and long-term results. The BMP-7 peptide was derived from the knuckle epitope of bone morphogenic protein-7 (BMP-7) and was conjugated via a cysteine amino acid at the N-terminus. Mouse RAW 264.7 monocytes/macrophages were seeded on the CoCr substrates and inflammation was induced via lipopolysaccharide (LPS) challenge. The effects of BMP-7 peptide on inflammation were evaluated by measuring the expression of inflammatory markers like toll-like receptor-4 (TLR-4), tumor necrosis factor-α (TNF-α), and monocyte chemotactic protein-1 (MCP-1). ELISA and qPCR assays were used to study the inflammatory signals. BMP-7 signaling pathway activation was shown by the presence of phosphorylation of Smad1/5/8. Utilizing the reactivity of polydopamine films to immobilize BMP-7 peptide onto metal substrates may provide a promising approach for applications in situations where reduction of inflammation around implants would be beneficial in improving surgical outcome, bone healing, and implant integration. Biotechnol. Bioeng. 2013; 110: 969-979. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Restenosis is a pivotal factor that restricts the efficacy of coronary artery bypass grafting. Inhibition of vascular smooth muscle cells (VSMCs) proliferation can improve intimal hyperplasia and lumen stenosis. Irisin, a polypeptide secreted by muscle cells, has been demonstrated to have a protective role in various cardiovascular diseases. However, the effect and mechanism of irisin on VSMCs proliferation and phenotype switching remain unclear. Cell proliferation ability was assessed using the methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay and 5-ethynyl-2'-deoxyuridine (EdU) incorporation. Cell cycle analysis was performed using flow cytometry, while expression levels of contractile and synthesis-related proteins were determined through RT-qPCR and Western blot. The VSMCs were infected with an adenovirus carrying GFP-LC3, and the proportion of cells showing positive expression was assessed. Additionally, the formation of autophagic lysosomes in cells was observed through transmission electron microscopy. In this study, we have demonstrated the inhibitory effects of irisin on the proliferation and phenotypic transition of platelet-derived growth factor-BB (PDGF-BB)-induced VSMCs. More importantly, we have discovered that irisin can activate the AMP-activated protein kinase/mammalian target of rapamycin (AMPK/mTOR) signaling pathway to mediate autophagy in PDGF-BB-induced VSMCs. The inhibitory effect of irisin on PDGF-BB-induced VSMCs proliferation was significantly attenuated by the AMPK inhibitor, Compound C. Conversely the mTOR inhibitor, rapamycin further enhanced the inhibitory effect of irisin on PDGF-BB induced VSMCs proliferation. In conclusion, our findings suggest that irisin effectively suppresses the aberrant proliferation of VSMCs following PDGF-BB stimulation by modulating autophagy levels through the AMPK/mTOR signaling pathway.

Introduction: Endovascular therapy (EVT) for intracranial arterial aneurysms is depicted with several complications. Very recently, delayed non-ischemic cerebral enhanced (NICE) lesions have been identified as a rare complication associated with EVT. This complication always stands a higher chance of being missed in asymptomatic patients. We report a case of multiple NICE lesions in a known chronic hepatitis B infection and chronic gastritis patient with left internal carotid aneurysm (ICA) treated with detachable coils., Case Presentation: A 52 years old female with left ICA was treated with detachable coils via the endovascular route. Three weeks after the operation, she presented with numbness of her right limbs which was persistent and waked her up from sleep each night. She admitted skin allergies after wearing metals except for gold and silver since childhood. MRI revealed multiple abnormal lesions in the left temporal lobe, hippocampus, insula, and parietal lobe and some perifocal edema which were consistent with the diagnosis of delayed NICE lesions., Conclusion: It is very important to report the occurrences of these lesions in literature because of their allergic origin. We advocate that allergy to metals especially those used in coating endovascular equipment should be evaluated before every EVT for intracranial aneurysms., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)