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Cardiac remodeling is an important mechanism of heart failure, which frequently results from leukocyte infiltration. Vascular cellular adhesion molecule-1 (VCAM-1) plays a critical role in leukocyte adhesion and transmigration. However, the importance of VCAM-1 in the development of angiotensin II (Ang II)-induced cardiac remodeling remains unclear. Wild-type (WT) mice were infused with Ang II (1,000 ng/kg/min) for 14 days and simultaneously treated with VCAM-1 neutralizing antibody (0.1 or 0.2 mg) or IgG control. Systolic blood pressure (SBP) and cardiac function were detected by a tail-cuff and echocardiography. Cardiac remodeling was evaluated by histological staining. Adhesion and migration of bone marrow macrophages (BMMs) were evaluated in vitro. Our results indicated that VCAM-1 levels were increased in the serum of patients with heart failure (HF) and the hearts of Ang II-infused mice. Furthermore, Ang II-caused hypertension, cardiac dysfunction, hypertrophy, fibrosis, infiltration of VLA-4+ BMMs and oxidative stress were dose-dependently attenuated in mice administered VCAM-1 neutralizing antibody. In addition, blocking VCAM-1 markedly alleviated Ang II-induced BMMs adhesion and migration, therefore inhibited cardiomyocyte hypertrophy and fibroblast activation. In conclusion, the data reveal that blocking VCAM-1 ameliorates hypertensive cardiac remodeling by impeding VLA-4+ macrophage infiltration. Selective blockage of VCAM-1 may be a novel therapeutic strategy for hypertensive cardiac diseases.

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Abstract. According to the complex process and lots of equipment, there are risks in gas compressor station. At present, research on integrity management of gas compressor station is insufficient. In this paper, the basic principle of Risk Based Inspection (RBI) and the RBI methodology are studied; the process of RBI in the gas compressor station is developed. The corrosion loop and logistics loop of the gas compressor station are determined through the study of corrosion mechanism and process of the gas compressor station. The probability of failure is calculated by using the modified coefficient, and the consequence of failure is calculated by the quantitative method. In particular, we addressed the application of a RBI methodology in a gas compressor station. The risk ranking is helpful to find the best preventive plan for inspection in the case study. Keywords. RBI; Risk Analysis; Gas compressor station; IntroductionThe gas compressor station is the pressurizing part of the pipeline, once the explosion damage is great, and the shock waves generated great, huge shock waves also endanger the people and things surrounding. The integrity management in the gas compressor station is to identify and evaluate the risk of the gas compressor station by using scientific methods. It is a kind of advanced risk prevention and risk management method. Effective measures are taken to eliminate or reduce the impact of risk so that the risk can be controlled in the acceptable range. Finally, accidents are reduced to guarantee safety operation of the gas compressor station in an economic and reasonable way. RBI is an effective way to solve pressure vessel and pipeline integrity problems in the gas compressor station. By Risk analysis of pressure vessels or pipes, the failure mechanism and testing technology of the pressure vessel or pipeline can be determined. Further, inspection plan and spare parts plan can be optimized. Besides, the scientific decision can be provided to support for prolonging the service life and shortening the maintenance period [1]. The RBI technology originated in the nuclear power industry, in the 1970s. In 1985, the American society of mechanical engineering (ASME) set up a research group of risk analysis. From 1991 to 1999, the ASME have published the RBI guidance documents in different industries [2]. Because of the Det norske veritas (DNV) has the ability in risk management and the experience in performing integrity around the world for a long time [3], American Petroleum Institute (API) seeks cooperation with DNV in the Early 1990s. They have successfully transplanted the RBI technology to the integrity management of petrochemical equipment, and have promulgated the RBI technology in the field of two landmark