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Background: Early detection of coronary atherosclerotic diseases (CAD) without regional wall motion abnormality (RWMA) is important for improving the outcome of cardiovascular events. Global myocardial work (GMW), including global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), and global myocardial work efficiency (GWE), offer comprehensive quantitative assessment of myocardial function in CAD. Hypothesis: We hypothesized that GMW could provide incremental value in detecting CAD without RWMA. Methods: One hundred and twenty‐four patients referred for coronary angiography (CAG) without resting RWMA were enrolled in this study. Global longitudinal strain (GLS), GWI, GCW, GWW, GWE were quantified. The severity of coronary lesions was evaluated by Gensini score (GS) based on CAG. We further divided CAG‐confirmed CAD patients into three subgroups according to the tertiles of GS: low 0 < GS ≤ 17, mid 17 < GS ≤ 38, and high GS > 38. Results: Compared with control, CAD patients showed decreased GLS, GWE, GWI, GCW but an increased GWW. Compared to low‐GS group, GWW was increased in the mid‐GS group. GLS, GWE, GWI and GCW were decreased in the high‐GS group while GWW was increased. Receiver operator characteristic curve analysis demonstrated that GWE was the most powerful predictor of high‐GS and was superior to GLS. GWE under 92.0% had the optimal sensitivity and specificity for identifying high‐GS. Conclusion: The proposed GWE, which outperformed the conventional GLS, could be considered as a potential predictive indicator to help to detect severe coronary disease in non‐RWMA CAD patients. [ABSTRACT FROM AUTHOR]

The aim of the present work was to examine the effect of polyethylene glycol (PEG)-coated superparamagnetic iron oxide (SPIO) nanoparticles carrying Pik3cb short hairpin RNA (shRNA) in the prevention of restenosis with the aid of ultrasound and a magnetic field. SPIO is a type of contrast agent used in medical imaging to enhance the visibility of specific tissues or organs. It consists of tiny iron oxide nanoparticles that can be targeted to specific areas of interest in the body. PEG-coated SPIO nanoparticles carrying Pik3cb shRNA (SPIO-shPik3cb) were prepared, and the particle size and zeta potential of PEG-coated SPIO nanoparticles with and without Pik3cb shRNA were examined. After a right common artery balloon-injured rat model was established, the rats were randomly divided into four groups, and the injured arteries were transfected with SPIO-shPik3cb, saline, SPIO-shcontrol and naked shRNA Pik3cb. During the treatment, each group was placed under a magnetic field and was transfected with the aid of ultrasound. Rats were sacrificed, and the tissue was harvested for analysis after 14 days. The results suggested that the mean particle size and zeta potential of SPIO-shPik3cbs were 151.45 ± 11 nm and 10 mV, respectively. SPIO-shPik3cb showed higher transfection efficiency and significantly inhibited the intimal thickening compared with naked Pik3cb shRNA in vascular smooth muscle cells (VSMCs) (* P  < 0.05). Moreover, SPIO-shPik3cb could also significantly downregulate the expression of pAkt protein compared with naked Pik3cb shRNA. According to the results, SPIO-shPik3cb can remarkably inhibit the intimal thickening under a combination of magnetic field exposure and ultrasound. [ABSTRACT FROM AUTHOR]

Magmatic sulphides largely control the behaviour of chalcophile elements in evolving magmas and also play critical roles in ore-forming processes at convergent plate margins. Magmas at the back-arc spreading centre of Mariana Trough are less affected by slab-derived fluids than Mariana arc basalts. However, whether the evolution of chalcophile elements in Mariana Trough magmas resembles or differs from those in arc magmas is poorly known. Based on the detailed petrological and geochemical studies, we present high-precision analyses of whole-rock chalcophile element (S, Cu, Ag, Re, Pd, Pt, Ru, Ir) contents for a suit of basaltic lavas (n = 15) from the central Mariana Trough. The occurrence of sulphides in high-Mg olivine crystals (Fo80) indicates that at least one episode of sulphide saturation occurred during early-stage magmatic evolution. The sulphur contents of most basalts were not significantly affected by degassing processes due to low oxidation state and high hydrostatic pressures. Instead, progressive fractionation of liquid sulphide with magmatic evolution is the dominant process, as reflected by sulphide petrography, the decrease in Cu, Ag, Pd, and Pt contents, and concomitant increase in Cu/Pd ratios (22,500–708,500), as well as nearly constant Cu/Ag (mean of 3137 ± 848, 1s) with decreasing MgO. We attribute early sulphide saturation of Mariana Trough basalts to their generation and evolution under relatively reducing conditions, with the limited effect of slab components. Combined with data from other island arc and back-arc lavas, we further show that the extent of adding slab-derived components, regardless of specific arc and back-arc tectonic settings, are determinants of the sulphide evolution and chalcophile element behaviour in magmatic systems above intra-oceanic subduction zones. Early magmatic sulphide saturation at central Mariana Trough would result in barren magmatic systems that are not suitable for the large-scale Cu-Au mineralization at the seafloor. [ABSTRACT FROM AUTHOR]

Zircon U-Pb ages, major element and trace element compositions, and Sr, Nd, and Pb isotopic compositions for late Mesozoic granites from the southern Jiaodong Peninsula (eastern China) were determined. Ages for the Wulianshan, Xiaozhushan, and Dazhushan plutons are 119.1-122.3, 114.2, and 108.9 Ma, respectively. Major and trace element characteristics show that these granitic rocks belong to alkaline, A-type granites formed in an extensional setting. Trace element compositions show strong, variable negative anomalies in Ba, K, P and Ti, and positive anomalies in Rb, Th, U, Pb, Ce, Zr, and Hf, which are typical characteristics of A-type granites. Variable Sr and Nd isotopic compositions, 87Sr/86Sr(i) = 0.70540-0.7071 and εNd(t) = −14.5 to −20.9. Whole-rock Pb isotopic compositions have the following ranges, (206Pb/204Pb)t = 15.707-16.561, (207Pb/204Pb)t = 15.376-16.462, and (208Pb/204Pb)t = 36.324 to 37.064. Isotopic modelling indicates an origin that lies between mantle tapped by Cenozoic basalts around the Tan-Lu megafault and lower continental crust (LCC), and which can be explained by mixing of 11-18% mantle and 82-89% LCC. Based on new and compiled data, we suggest that the southern Jiaodong Peninsula, as well as the Laoshan area, was in a regional extensional setting of an orogenic belt during 106-126 Ma. The granitic rocks may be the result of late Mesozoic lithospheric thinning and decratonization (i.e. late Mesozoic craton destruction event occurring throughout eastern China). [ABSTRACT FROM AUTHOR]

ADP-ribosylation factor 6 (Arf6), a member of the ADP-ribosylation factor family, is overexpressed in different types of cancer cell and promotes invasion, metastasis and drug resistance. However, the potential functions of Arf6 in gastric cancer (GC), and the molecular mechanism underlying these functions, remain to be fully elucidated. In the present study, the results demonstrated that in vitro knockdown of Arf6 decreased proliferation, colony formation, migration and invasion in SGC-7901 cells. Arf6 knockdown also markedly decreased the activity of the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway. Furthermore, knockdown of Arf6 was associated with elevated chemosensitivity of SGC-7901 cells to 5-fluorouracil through inactivation of the ERK1/2 signaling pathway. Taken together, these results suggest that Arf6 is involved in regulating proliferation, migration, invasion and drug resistance in GC, and may be a potential therapeutic target for the treatment of GC. [ABSTRACT FROM AUTHOR]