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Hydrogen sulfide (H2S), a novel gaseous signaling molecule, is a vital physiological signal in mammals. H2S protects the cardiovascular system via modulation of vasodilation, vascular remodeling, and inhibition of vascular calcification, and also has anti-atherosclerosis properties. Autophagy is a lysosomal-mediated intracellular degradation mechanism for excessive or abnormal proteins and lipids. The contribution of autophagy to normal and disease-state cell physiology is extremely complicated. Autophagy acts as a double-edged sword in the cardiovascular system. It can defend against damage to cells caused by environmental changes and it can also induce active cell death under certain conditions. In recent years, accumulating evidence indicates that H2S can up- or downregulate autophagy in many pathological processes, thereby switching from a harmful to a beneficial role. In this review, we summarize progress on understanding the mechanism by which H2S regulates autophagy in cardiovascular disease. We also discuss a H2S switch phenomenon that regulates autophagy and provides protection in cardiovascular diseases.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Previous studies have shown that inflammatory chemokines are involved in the physiological functions of cytoskeletal reorganization, cell migration, adhesion and immune responses. However, in the past decade, there have been studies showing that inflammatory chemokines play a key role in CVD. Importantly, CXC motif chemokine ligand 2 (CXCL2) has been shown to be involved in the pathogenesis of cardiovascular disease. CXCL2 exerts its effects on the cardiovascular system by mediating inflammatory responses, but the specific signaling pathways by which CXCL2 exerts its effects in CVD remain unknown and need to be further investigated. This review aims to investigate the expression changes of CXCL2 in acute myocardial infarction (AMI), atherosclerosis (AS), obesity, diabetes and ischemic stroke (IS) and its potential key role in cardiovascular disease in order to provide new ideas for the prevention and treatment of cardiovascular diseases.

Autophagy is conserved in nature from lower eukaryotes to mammals and is an important self-cannibalizing, degradative process that contributes to the elimination of superfluous materials. Cardiac hypertrophy is primarily characterized by excess protein synthesis, increased cardiomyocyte size, and thickened ventricular walls and is a major risk factor that promotes arrhythmia and heart failure. In recent years, cardiomyocyte autophagy has been considered to play a role in controlling the hypertrophic response. However, the beneficial or aggravating role of cardiomyocyte autophagy in cardiac hypertrophy remains controversial. The exact mechanism of cardiomyocyte autophagy in cardiac hypertrophy requires further study. In this review, we summarize the controversies associated with autophagy in cardiac hypertrophy and provide insights into the role of autophagy in the development of cardiac hypertrophy. We conclude that future studies should emphasize the relationship between autophagy and the different stages of cardiac hypertrophy, as well as the autophagic flux and selective autophagy. Autophagy will be a potential therapeutic target for cardiac hypertrophy.

Cardiovascular disease is a growing major global public health problem. Oxidative stress is regarded as one of the key regulators of pathological physiology, which eventually leads to cardiovascular disease. However, mechanisms by which FGF-2 rescues cells from oxidative stress damage in cardiovascular disease is not fully elucidated. Herein this study was designed to investigate the protective effects of FGF-2 in H2O2-induced apoptosis of H9c2 cardiomyocytes, as well as the possible signaling pathway involved. Apoptosis of H9c2 cardiomyocytes was induced by H2O2 and assessed using methyl thiazolyl tetrazolium assay, Hoechst, and TUNEL staining. Cells were pretreated with PI3K/Akt inhibitor LY294002 to investigate the possible PI3K/Akt pathways involved in the protection of FGF-2. The levels of p-Akt, p-FoxO3a, and Bim were detected by immunoblotting. Stimulation with H2O2 decreased the phosphorylation of Akt and FoxO3a, and induced nuclear localization of FoxO3a and apoptosis of H9c2 cells. These effects of H2O2 were abrogated by pretreatment with FGF-2. Furthermore, the protective effects of FGF-2 were abolished by PI3K/Akt inhibitor LY294002. In conclusion, our data suggest that FGF-2 protects against H2O2-induced apoptosis of H9c2 cardiomyocytes via activation of the PI3K/Akt/FoxO3a pathway.

The tensile strength, elognation and microstructure of alloy are respectively tested and observed after annealing treatment. The results show that the working rate the larger, the initial recrystallization temperature the lesser. The proper middle annealing process of Cu-Ag alloy with 80% deformation is 405°C×5h.

The tensile strength, elongation and microstructure of alloy are respectively tested and observed after annealing treatment. The results show that the working rate the larger, the initial recrystallization temperature the lesser. The proper middle annealing process of HSn88-1 alloy with 80% deformation is 460°C×5h.

A new IAQ improved ventilation system-reversible ventilation system was designed. This system's working principle was introduced. For analyzing the superiority of reversible ventilation system, the conceptions of effective fresh air ratio and minimum effective fresh air ratio were described. The formula of effective fresh air ratio was deduced. The formula can be used to analyze the different air outputs of reversible ventilation system and conventional general ventilation system, in rooms with the same degree of fresh air. It can be taken as the guide for design and actual applications of reversible ventilation system.

Novel two-stage solution heat treatments were applied to Cu-Cr-Zr alloy to improve its properties. The influences of these treatments on the microstructures and properties of the alloy were investigated by TEM, SEM, tensile testing and electrical conductivity test. The investigation showed that with the proposed solution treatments, it was possible to obtain better properties than the properties obtained by conventional single-stage solution treatment. For example, in the case of an alloy of Cu-0.4wt.%Cr-0.1wt.%Zr, it was found that a two-stage solution treatment system (8 h at 920 °C followed by 1 h at 1010 °C) produced better combination property than the conventional single-stage solution system (1 h at 950 °C) applied by other researchers. The first stage solution treatment is crucial to the dissolution of CuZr precipitates, dissolved CuZr phase completely, at the same time precipitated Cr phase. Subsequently, excess Cr precipitates all dissolved at the second stage solution treatment. As a result, a pure matrix is obtained after such two-stage solution heat treatments.

Cu-20Ni-5Sn alloy has not only high content of Ni melted point 1453°C, but also low melting point elements of Sn melted at 231.9°C, therefore, the grain structure of alloy as-cast is in perfect dendrite that lends to form segregation and inverse segregation of Sn, so that the hot rolling (cogging) processing is restricted. The influence of casting methods, cooling rate and heat treatment on the microstructures and properties of as-cast Cu-20Ni-5Sn alloy were investigated. The results show that, compared to the ingot casted in iron mold and graphite mold, the microstructure of Cu-20Ni-5Sn ingot prepared by horizontal continuous casting is the finest and the Sn segregation level is in lowest. The microstructure of the ingot casted in graphite mold is in the most perfected dendritic and with the highest segregation of Sn, the microstructure of ingot in iron molding is in the middle. The ingots must be homogenized before cold-processing. Homogenization treatment can eliminate Sn segregation and dissolve the non-equilibrium phase of ingots.

An investigation on behavior of the early stage of aging and its influence on theperformance of C17200 alloys is conducted in this paper. It is indicated that spinodal decomposition occured when the specimen is aged at 320 °C ,leading to the formation of G.P zones. A phase transformation from metastable precipitates to stable phase occurred with the increasing aging time, the sequence of which is believed as G..P→γ′′→γ′→γ. Spinodal decomposition and ordering of the matrix are found together in C17200 alloy.

The microstructural features and heat treatment response of Cu-2.1Ni-0.5Si-0.2Zr-0.05Cr (wt.%) alloy have been investigated. The alloy was aged at 400°C、450°C and 500°C after a cold deformation of 70% reduction. The variation in hardness and electrical conductivity of the alloy was measured as a function of aging time. The results indicated the highest peak hardness value of approximately 205HV for the alloy aged at 400°C for 4h after the solution treatment and cold deformation. The alloy has two main phases, one is Ni2Si phase, and the other is Cr2Zr phase. The strengthening mechanisms of the alloy include spinodal decomposition strengthening, ordering strengthening and precipitation strengthening.

O-Alkylation of oximes with N-vinylpyrrolidin-2-one or N-methyl-N-vinylacetamide was efficiently initiated by a catalytic amount of cerium (IV) ammonium nitrate (CAN), giving the corresponding oxime ether derivatives in good yield. (C) 2010 Long Min Wu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.