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Chromium (Cr) isotopes represent a powerful tool for tracing the redox conditions during planetary magmatic evolution. However, so far, the systematic investigation of Cr isotope variation has been only performed on ocean island basalts (OIBs) in terrestrial magmatic rocks. Therefore, the Cr stable isotope compositions (expressed as δ53Cr relative to NIST SRM 979) of other magmatic rocks, formed under different oxygen fugacity, have remained unconstrained. In this paper, we present the first Cr stable isotopic data of mid-ocean ridge basalts (MORBs) from the Eastern Pacific Ocean ridge, the Indian ridge, and the Atlantic Ocean ridge. The oxygen fugacity of such basalts is different from that of the above-mentioned OIBs. The Rhyolite-MELTS model shows that the chemical composition variations in the studied basalts are induced by varying extents of fractional crystallization of olivine, clinopyroxene, plagioclase, and spinel. The δ53Cr values of the MORBs range from −0.27 ± 0.03‰ to −0.07 ± 0.02‰ (n = 28), and two distinct groups of basalts are identified based on the correlation between δ53Cr and MgO. On the one hand, the δ53Cr of group I basalts (−0.27 ± 0.03‰ to −0.14 ± 0.03‰; n = 24) are systematically lower than the established average value of the Bulk Silicate Earth (BSE) (δ53Cr = −0.12 ± 0.04‰; 2SD), which are positively correlated with their MgO and Cr concentrations, indicating that Cr isotopes are fractionated during magmatic differentiation. Moreover, Rayleigh fractionation modelling suggests that the crystallization of olivine, clinopyroxene, and spinel gives rise to the Cr depletion and thereby decreases δ53Cr values. On the other hand, group II basalts (−0.10 ± 0.03‰ to −0.07 ± 0.02‰; n = 4) exhibit higher δ53Cr values than group I with identical MgO and Cr concentrations. This is possibly associated with the crystallization of clinopyroxene under low pressure. The average Cr isotope composition (δ53Cr = −0.16 ± 0.02‰, n = 3) of the primitive basalts (MgO > 9%) represents that of the primary MORB melt, which is lighter than the average value of BSE. Using the non-modal melting equations, the δ53Cr of the MORB mantle source is estimated to be −0.12 ± 0.02‰ (2σ), which is consistent with that of BSE. Compared with the Cr isotopic data of OIBs from Fangataufa island, we find that the equilibrium fractionation factors (Δ53Cr crystal-melt = +0.04‰ to +0.13‰) of MORBs during fractional crystallization are larger than that of Fangataufa island lavas (Δ53Cr crystal-melt = 0.010 ± 0.005‰ for low-K suite, and 0.020 ± 0.010‰ for high-K suite; Bonnand et al., 2020a), indicating that the basalts from Fangataufa island have higher oxygen fugacity than those of MORBs analyzed in this study, which is strongly supported by their higher V/Sc ratios. [ABSTRACT FROM AUTHOR]

Sulfur is one of the key volatiles in Earth's chemical cycles that is transferred into the mantle at subduction zones by slab-dehydrated fluids and is returned to the crust via arc-related magmatism. Therefore, sulfur plays an important role in mantle oxidation, porphyry ore deposit formation and is also linked to the transport of chalcophile elements between mantle and crust. Here, we analyzed Zn isotopes and S concentrations in combination with 87Sr/86Sr (i) ratios and trace element compositions in eclogites from Southwestern Tianshan and Northern Qilian to decipher the sulfur cycling in subduction channel. The protoliths of these eclogites are the mid-ocean ridge basalts (MORB)−/ ocean island basalt (OIB)-type mantle. However, most samples have lighter δ66Zn (0.10‰ to 0.30‰) and higher sulfur contents compared to these typical mantle values. Given the limited fractionation of Zn isotopes during metamorphic dehydration, these relationships suggest that the eclogites have been modified by S-enriched fluids with low δ66Zn values. Negative correlations between δ66Zn and S contents resp. Zn contents are also observed in these samples. We suggest that two distinct fluids have modified these eclogites: a mica-derived fluid 1 which resulted in high concentrations in large ion lithophile element (LILE; e.g., Ba, Cs, and K) and low δ66Zn values that range from 0.22 ‰, i.e., slightly below mantle values down to 0.13 ‰, and an epidote-derived fluid 2 that produced eclogites with high 87Sr/86Sr (i) , elevated Pb contents and δ66Zn values that are distinctly below typical mantle values (0.28 ± 0.05‰). Model calculation reveals that such fluids are mainly composed of Zn-HS/Cl complexes, which is further verified by presence of chalcopyrite in the eclogites. Thus, we conclude that reduced sulfide/Cl–rich, slab sediment–derived fluids existed in the subduction channel that formed the eclogites of Southwest Tianshan and Northern Qilian. A significant flux of sulfate to the oxidize sub-arc mantle wedge is not indicated. • Zinc isotope compositions of eclogites from northern Qilian and SE Tianshan are investigated. • The δ66Zn values of most eclogites are lower than those of mi-ocean ridge basalts. • These eclogites have been modified by two types of sediments-derived fluids. • The low δ66Zn values of eclogites indicate modification by S-rich reduced fluid. [ABSTRACT FROM AUTHOR]

Abstract The natural course of otitis media in children is acute and self-limiting. Nevertheless, about 10–20% children could experience recurrent or persistent otitis media. Thus, finding effective candidate to prevent acute otitis media is urgently required. In our study, mouse acute otitis media model was constructed by lipopolysaccharide (LPS) injection into the middle ear of mice via the tympanic membrane. Apigetrin (APT) is a flavonoid isolated from various herbal medicines, possessing anti-inflammatory and anti-oxidative bioactivities. However, if APT could attenuate acute otitis media in LPS-induced animal models, little is to be known. Hematoxylin and eosin (H&E) staining suggested that APT treatment reduced LPS-induced higher mucosa thickness. LPS-triggered inflammatory response was also inhibited by APT, as evidenced by the down-regulated neutrophils and macrophages. Additionally, the reduced inflammatory factors, including interleukin-1β (IL-lβ), tumor necrosis factor α (TNF-α), IL-6 and vascular endothelial growth factor (VEGF) were observed in APT-treated mice with acute otitis media. The process was associated with the inhibition of toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) pathway, which was proved by the blockage of TLR4, MyD88, p-IKKα, p-IκBα, and p-NF-κB using western blot analysis. Moreover, the production of reactive oxygen species (ROS) caused by LPS was also reduced by APT through promoting anti-oxidants, involving superoxide dismutase (SOD) activity, heme oxygenase-1 (HO-1), NADP(H) quinone oxidoreductase 1 (NQO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) expressions. In contrast, high levels of MDA and kelch-like ECH-associated protein 1 (Keap 1) in LPS-treated mice were down-regulated by APT, which might be associated with the inactivation of NF-κB. In vitro, APT exhibited anti-inflammatory and anti-oxidant effects with little cytotoxicity in LPS-stimulated cells. Together, the data above indicated that APT could ameliorate acute otitis media through inhibiting inflammation and oxidative stress. [ABSTRACT FROM AUTHOR]

Objective Invasion and metastasis of papillary thyroid carcinoma (PTC) significantly affects prognosis and quality of life of patients. Herein, we explored the binding relationship of long noncoding RNA PVT1 as ceRNA to microRNA-30a (miR-30a), and their effect on the development of PTC through regulating insulin like growth factor 1 receptor (IGF1R). Methods PTC and adjacent normal tissues were collected, where the qRT-PCR and western blot assay were employed to evaluate the expression levels of PVT1, miR-30a and IGF1R. The correlation between PVT1 expression and clinicopathological characteristics of PTC patients was observed. PTC cell lines with the most/least significant difference from normal thyroid cells were selected and treated with siRNA PVT1 or overexpression PVT1 plasmids, miR-30a mimics or miR-30a inhibitors. Nucleus and cytoplasm segmentation was used to identify subcellular fractionation of PVT1. The binding relationship of PVT1 to miR-30a and the targeting relationship of miR-30a to IGF1R were confirmed by using bioinformatic prediction program, dual-luciferase reporter gene assay and RNA-pull down. Cell viability, cell cycle and apoptosis, invasion and migration capacities were assessed by MTT, flow cytometry, Transwell assay and scratch test, respectively. Western blot assay was employed to examine protein expression of IGF1R, apoptosis-related factors (caspase-3, cleaved capase-3) and epithelial-mesenchymal transition (EMT)-related factors (E-cadherin, Vimentin). Results In the PTC tissues and cells, PVT1 and IGF1R were highly expressed and miR-30a was poorly expressed. PVT1 exerted its effects on PTC mainly in the cytoplasm. The PVT1 expression was correlated with TNM staging, LNM and tumor infiltration of PTC. The competitive binding of PVT1 to miR-30a enhanced expression of IGF1R. In the in vitro experiments, BCPAP and TPC-1 cells were selected. When subjected to siRNA PVT1 or miR-30a mimics, BCPAP and TPC-1 cells exhibited inhibited proliferation, cell cycle progression, invasion, migration, EMT (increased E-cadherin and reduced Vimentin) and promoted apoptosis (reduced caspase-3 and increased cleaved capase-3), and moreover, the expression of IGF1R was reduced. Conclusion This study provides evidence that long noncoding RNA PVT1 enhances the expression of IGF1R through competitive binding to miR-30a, whereby PVT1 facilitates the development of PTC. [ABSTRACT FROM AUTHOR]

The aim of this retrospective study was to explore the reproductive outcomes of IVF treatment in women with primary ovarian insufficiency (POI) showing intermittent follicular development. A total of 44 POI women with normal karyotype and absent autoimmunity, attending the centre for fertility treatment at Nanfang Hospital, Guangzhou from March 2009 to March 2011, were identified as suitable for inclusion in this study. Out of 44 women, 20 (20/44; 45.5%) had growing follicles and 13 underwent 27 oocyte retrievals. The empty follicle rate per oocyte retrieval was 70.4% (19/27); eight oocytes were recovered: one (12.5%) germinal vesicle (GV), two (25.0%) metaphase I (MI), one (12.5%) metaphase II (MII), and four (50.0%) atretic. One MI oocyte matured in vitro and two women had embryo transfer. Only the woman with the MI oocyte matured in vitro conceived, giving birth to a healthy baby at term. These results suggest that intermittent follicular development is common in women with POI but most of the developed follicles are empty or contain atretic oocytes. The pregnancy rate remains very low for IVF treatment. [ABSTRACT FROM AUTHOR]

Abstract: Oil recovery can be greatly enhanced with the ASP (Alkali/Surfactant/Polymer) flooding technology by increasing sweeping efficiency and displacing efficiency. But the emulsification of the residual chemical in the recovered oil from ASP flooding makes it very difficult to separate water from oil. To make the oil–water separation of ASP products more efficient to meet the discharge standards, some improvements need to be made on regular oil–water separators. Based on the physical properties of ASP products in Daqing Oilfield, novel packing and newly designed Crude oil–water separator are studied in this paper. Orthogonal test is used to optimize the design of the novel separator, including the structure and material of coalescent packing, as well as the operating conditions. Experiment results suggest that the separation efficiency of the new type separator is higher than 98%. Both the outlet oil phase and the water phase have met the corresponding standards. Oil concentration in the discharge water is reduced to 600 mg L−1 and average drop size is about 6 μm. It can be easily concluded that the new type separator has a better performance on the oil–water separation of ASP products. At the end of this paper, the drop size distribution (DSD) in the outlet water is analyzed to provide data for the wastewater treatment process following the crude oil–water separation. [Copyright &y& Elsevier]