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The carbides evolution affected by heating will have great effect on the mechanical property of welded components. The paper focused on the microstructure characterization and carbides evolution under different thermal cycle in narrow-gap tungsten inert gas welding (NG-TIG) on Alloy 617B. The carbides were characterized to be M 23 C 6 by TEM in 617B base metal (BM), which distribute along the grain boundaries and within the grains in roughly similar size and characteristics. However, many kinds of multi-carbides and various characteristics were found in heat affected zone (HAZ) with different distance to fusion line, which contributed to different heating peak temperatures ( T p ). As the T p reaches the solvus temperature of M 23 C 6 carbides, M 23 C 6 carbides show partial dissolution and M 6 C will form at the interface γ/M 23 C 6 due to the segregation of element Mo. Upon the eutectic temperature, the surviving M 23 C 6 carbides react with the surrounding γ matrix and then it leads to the formation of liquid film. Some phases with lamellar structure composed of M 6 C and M 23 C 6 multi-carbides and islands of γ-austenite will occur as the temperature decreases. In addition, a large number of fine granular Cr-rich second phases like texturing morphology, scattered around each new kind of multi-carbide after the post weld heat treatment (PWHT). Basing on the analysis result, it can be seen that the evolution behavior of carbides is determined by the thermal input during NG-TIG welding process. No adverse effects, such as liquation cracking, have been brought into the welded joint due to the low thermal input, proving that NG-TIG is a suitable welding method to join Alloy 617B. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ginsenoside Rc could reduce cartilage damage in RA rat model. • Ginsenoside Rc could inhibit pro-inflammatory cytokines release and production in joint of RA rat. • Ginsenoside Rc could downregulate the NF-κB signaling pathway. Ginsenoside Rc (GRc), an active component isolated from ginseng, has been reported to have anti-inflammatory properties. However, the potential mechanism of its effect on rheumatoid arthritis (RA) is not reported. The present study established the RA model by injection of complete Freund's adjuvant in the hind paw. GRc was administrated by gavage daily. The results showed that GRc ameliorated the swelling rate of both hind paws and reduced the arthritis score in rats. Meanwhile, GRc inhibited cartilage damage and inflammatory cell infiltration in the joint tissue. Furthermore, GRc significantly decreased the concentration of pro-inflammatory cytokines in the joint tissue of rats. Additionally, GRc downregulated the NF-κB signaling pathway. In conclusion, these findings show that GRc remarkably reduced cartilage damage and inflammatory response in the RA rat model by inhibiting of NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: Juglone is a natural compound which has been isolated from Juglans mandshurica Maxim. Recent studies have shown that juglone had various pharmacological effects such as anti-viral, anti-bacterial and anti-cancer. However, its anti-cancer activity on human prostate cancer LNCaP cell has not been examined. Thus, the current study was designed to elucidate the molecular mechanism of apoptosis induced by juglone in androgen-sensitive prostate cancer LNCaP cells. MTT assay was performed to examine the anti-proliferative effect of juglone. Occurrence of apoptosis was detected by Hoechst 33342 staining and flow cytometry in LNCaP cells treated with juglone for 24h. The result shown that juglone inhibited the growth of LNCaP cells in a dose-dependent manner. Morphological changes of apoptotic body formation after juglone treatment were observed by Hoechst 33342 staining. This apoptotic induction was associated with loss of mitochondrial membrane potential, and caspase-3, -9 activation. Moreover, we found that juglone significantly inhibited the expression levels of androgen receptor (AR) and prostate-specific antigen (PSA) in a dose-dependent manner, as well as abrogated up-regulation of AR and PSA genes with and/or without dihydrotestosterone (DHT). Take together, our results demonstrated that juglone might induce the apoptosis in LNCaP cell via down-regulation of AR expression. Therefore, our results indicated that juglone may be a potential candidate of drug for androgen-sensitive prostate cancer. [Copyright &y& Elsevier]

[Display omitted] • GPS attenuated inflammation via JAK2/STAT1/NLRP3 inflammasome signalling pathway in IBD model. Panax ginseng polysaccharides (GPS) are isolated from Panax ginseng C. A. Meyer, which has many pharmacological activities. However, although the protective effect of GPS on inflammatory bowel disease (IBD) has been characterized, its mechanism has not yet been fully elucidated. In the present study, we clarified it effect on IBD in mice and studied the mechanism of reducing inflammation. IBD model was established in mice by administrating dextran sulfate sodium (DSS) in drinking water for 7 days. Our results showed that GPS treatment significantly relieved disease activity index, colon length shortening and pathological changes in colonic tissue. Furthermore, GPS treatment significantly reduced oxidative stress and inflammatory cytokines in the colonic tissue via inhibiting JAK2/STAT1/NLRP3 inflammasome signalling pathway. In conclusion, these results demonstrated that GPS could attenuate inflammatory response via inhibiting JAK2/STAT1/NLPR3 inflammasome signalling pathway. Hence, GPS may be a potential natural medicine to inhibit JAK2/STAT1/NLRP3 inflammasome signalling pathway and reduce inflammation in IBD. [ABSTRACT FROM AUTHOR]

• TMFP can protect diabetic cardiomyopathy in diabetic rat. • TMFP attenuated oxidative stress by increasing Nrf2 and HO-1 gene expression. • TMFP inhibited inflammation by decreasing cytokines. • TMFP alleviated apoptosis by mitochondrial pathway. The leaves of Murraya paniculata (L.) Jack were used as spices in China for many years. Flavonoids are the main components of it. However, no study has determined whether the total flavonoids of Murraya paniculata (L.) Jack (TFMP) has preventive effects on diabetic cardiomyopathy (DCM).The present study investigated the effect of TFMP on DCM. STZ was administered along with a high-fat diet to induce diabetes in rats. Parallel experiments were performed using H9c2 cells exposed to high glucose. Diabetic rats showed serious histological changes and increased levels of cardiac function markers. The markers of ROS, inflammation and apoptosis were also increased significantly, but the antioxidant defenses were decreased. Treatment with TFMP alleviated histological alteration in the myocardium. TFMP suppressed oxidative stress, inflammation and apoptosis. Our results demonstrate that the protective of TFMP on DCM is associated with increasing Nrf2 and HO-1 gene expression and inhibiting oxidative stress, inflammation and apoptosis. [ABSTRACT FROM AUTHOR]

Abstract The microstructure evolution was characterized in detail for nickel-based weld metal with multi-layers manufactured by narrow gap arc welding technology after thermal exposure at 750 °C up to 12,000 h. The coarsening kinetics of precipitations and its intrinsic correlation with mechanical properties were investigated and revealed. As exposure time lasted, the hardness of weld metal increased. The toughness decreased dramatically and the ripening rate of γ´ phases dropped with a slow rate of 0.0047 nm/h, finally kept stable rate when exposure time exceeded 8000 h. The coarsening rate constant of 3.86 × 10−29 m3/s for γ′ phases indicated lower coarsening kinetics and higher ripening resistance, which contributed to the good thermal stability for the weld metal. A mass of needle-like M 6 C carbides was found among interdendritic regions and on the grain boundaries, which became coarser with increasing exposure time due to the segregation of element Mo. Another finding was that spherical γ′ phases grew at the expense of the smaller ones and achieved stabilization at long-term exposure time. As the main factor for reducing toughness, the growth of needle-like shape M 6 C could be inhibited by the γ′ phases around them via preventing Mo and Cr as M 6 C-forming elements diffusing, giving rise to the stable toughness. Highlights • The Mo segregation promotes the precipitation and coarsening of needle-like M 6 C during thermal exposure at 750 °C. • Spherical γ′ phases coarsen with a low coarsening rate constant of 3.86 × 10−29 m3/s following the Ostwald ripening theory. • The precipitation of γ′ phases at the face sites of M 6 C help to give rise to a stable acicular shape of the latter. • Evolution behavior of M 6 C and γ′ phases causes the toughness to dramatically decrease and then stabilize from 8000 h. [ABSTRACT FROM AUTHOR]

In this paper, evolution of Laves phase in weld metal (WM) during long-term creep exposure was investigated for modified 9Cr-1.5Mo-1Co steel welded joint (WJ) by microstructure characterization and theoretical calculation based on a series of creep tests at 620 °C. It was found that some rod-like Mo-rich Laves phase precipitated adjacent to M 23 C 6 carbides on grain boundary and other isolated polygonal Laves phase particles formed in grains after long-term creep exposure. Number and size of Laves phase increased simultaneously at early stage of precipitation. The volume fraction nearly approached to equilibrium fraction while coarsening was still ongoing after 2500 h. Johnson-Mehl-Avrami and Ostwald ripening model indicated that precipitation of Laves phase was controlled by grain boundary diffusion with a decreasing rate. EDS results showed Laves phase in WM had the highest Mo content in the whole WJ. The pinning effects on grain boundaries by Laves phase became weaker during creep exposure due to its coarsening. More high angle boundaries and sub-structure in WM from EBSD results provided more potential sites for Laves phase nucleating. With Laves phase particles growth on grain boundaries in WM, solid solution elements like Mo in matrix were severely depleted, resulting in loss of solute strengthening effect and precipitation strengthening effect, thus leading to the rupture in WM. Unlabelled Image • Evolution mechanism of Laves phase was investigated. • Laves phase nucleated on grain boundaries with a decreasing rate. • Precipitation of Laves phase was controlled by grain boundary diffusion. • More HABs and sub-structure provided more nucleation sites in WM. • Severest Mo consumption and pinning effect loss accounted for long-term rupture. [ABSTRACT FROM AUTHOR]

Abstract: Acanthopanax senticosides B is a monomer of Acanthopanax senticosus saponins. Previous reports showed that Acanthopanax senticosus saponins exhibit antioxidant action and cardiac protection. However, whether Acanthopanax senticosides B has cardiac protection remains unknown. In this study, we investigated the effect of Acanthopanax senticosides B on oxidative damage induced by hydrogen peroxide (H2O2) of cardiomyocytes. As revealed from the results, when the cardiomyocytes were exposed to H2O2 for designed time and concentration, the percentage of survival cells was down significantly, the activity of lactate dehydrogenase (LDH) and the content of cellular malondialdehyde (MDA) were increased markedly. These results indicated that the cells were subjected to oxidative damage. Treatment with Acanthopanax senticosides B prior to H2O2 (100μM) exposure can increase cell viability significantly, lessen H2O2-induced cardiomyocyte morphological change, and inhibit augmentation of LDH activity in culture media and cellular MDA content markedly. Our results demonstrated that Acanthopanax senticosides B (400μg/ml and 200μg/ml) can protect cells against oxidative injury of H2O2 (100μM). Furthermore, the activities of superoxide dismutase (SOD), glutathione peroxidase, catalase and the content of reduced glutathione (GSH) of cardiomyocytes were also raised by Acanthopanax senticosides B. Taken together, the study implicated that Acanthopanax senticosides B protects cardiomyocytes against oxidative-stress injury induced by H2O2 through reduction of lipid peroxidation and enhancement of the activity of antioxidant defense. [Copyright &y& Elsevier]

Ginseng quinquefolium (L.), Astragalus membranaceus , and Sophora flavescens Aiton are popular folk medicines in many Asian countries and regions. These three traditional Chinese herbs and their extracts have been reported to considerably enhance the immune function. G. quinquefolium (L.) is considered the king of herbs in China. Traditionally, G. quinquefolium (L.) is believed to replenish vitality, which is considered as immune enhancement in modern Chinese pharmacy. One of the main uses of Astragalus is immunity enhancement; S. flavescens and oxymatrine obtained from its extract have been used to treat leukopenia. Considering the pharmacological properties of Ginseng , Astragalus , and oxymatrine, we evaluated the immunopotentiation effects of their combination, Ginseng–Astragalus –oxymatrine (GAO), in the present study. This study aimed to expand the clinical application of GAO and to preliminarily explore its mechanism of action by determining whether GAO injection can enhance immunity in vivo and in vitro. Overall, 17 major chemical components in GAO were analysed using HPLC and LC-MS. The immunity-enhancing effect of GAO was studied in the cyclophosphamide (CTX)-induced immunosuppressive mouse model and RAW 264.7 cells. Quantitative analysis showed that the potential active components of GAO include at least ginsenosides, astragaloside IV, and oxymatrine. GAO could significantly improve the nonspecific immunity including the indices of the thymus and spleen, number of peripheral blood leukocytes, levels of TNF-α and IL-6, phagocytic function of macrophages, and cytotoxic activity of natural killer (NK) cells. Additionally, GAO enhanced the humoural immunity, characterised by the antibody production ability of B cells, and cellular immunity, characterised by the activity of T cells, in immunosuppressed mouse. Moreover, GAO could enhance the phagocytic and adhesion functions of RAW 264.7 cells, which may be related to the activation of reactive oxygen species and NF-κB signalling pathway. GAO could dramatically ameliorate CTX-induced immunosuppression in mouse and stimulate the immune activity in RAW 264.7 cells possibly by activating the NF-κB signalling pathway. [Display omitted] [ABSTRACT FROM AUTHOR]