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Background: Unbalanced gut microbiota is considered to cause dysfunction of the gut barrier function. Lactobacillus johnsonii MG, isolated from mouse feces as gut associating lactobacilli, enhanced gut barrier function in Caco‐2 cells via interaction with JAM‐2 in tight junctions. In this study, the anti‐inflammatory effects of L. johnsonii MG were investigated in a colitis mouse model developed by treating mice with 3% dextran sulfate sodium (DSS) for 9 days. Results: MG treatment of colitis mice resulted in fast recovery of the body weight and showed significant improvement in the disease activity index and histopathological scores. The histomorphological score increased by DSS treatment was significantly improved in the MG‐treated group. In the intestine, the expression of Ocln, Zo1, Itga6, Lama3, and Jam2 genes, which are involved in tight junction functions, were significantly upregulated in MG‐treated colitis mice. In the microflora analysis, the abundance of Ruminococcaceae, Bacteroides, and Lachnospiraceae were reduced in DSS‐treated mice and recovered by MG treatment. Conclusion: We reported the potential of L. johnsonii MG in the regeneration of crypts and integrity of matrix proteins in the gut of mice with colitis through its association with tight junctions. The experimental results provide new insights into the probiotic effect of tight junction associating L. johnsonii MG. [ABSTRACT FROM AUTHOR]

• The microstructure analysis offers a novel window to test different formation models of net-textured Fe-Ti oxide ores. • Static recrystallization resulted in the straight or smoothly curved grain boundaries of Fe–Ti oxide grains. • The microstructural evidence suggests crystallization of Fe-Ti oxides from immiscible Fe-rich melt within crystal mush. The mafic–ultramafic layered intrusions in the Emeishan large igneous province (LIP) host significant amounts of Fe, Ti and V resources. The Fe-Ti oxide ore layers hosted in these layered intrusions are variable in thickness and it is enigmatic how the large amounts of Fe-Ti oxides are accumulated to form the Fe-Ti oxide ore layers. The Fe-Ti oxide ore layers are mainly composed of net-textured ores, however, the processes to form the net-textured ores have not yet been well constrained due to lack of diagnostic microstructural evidence of Fe-Ti oxides in the ores. Here we use the electron back-scattered diffraction (EBSD) technique to characterize the microstructures of Fe-Ti oxides in the net-textured ores of the Baima layered intrusion in the Emeishan LIP, e.g. , crystallographic orientation and neighbor-/random-pair misorientation, and to assess the formation model of net-textured ores. The net-textured ores are composed of silicate crystals (olivine, and minor plagioclase and clinopyroxene) isolated by interconnected matrix composed of Fe-Ti oxides (titanomagnetite and ilmenite) and minor sulfides. It is likely that the Fe-Ti oxides simultaneously crystallized from a common Fe–Ti–(P)-rich melt, but postdated olivine and other cumulus minerals. The compaction induced by the gravity of overlying cumulus minerals only caused weak intragrain deformation of Fe-Ti oxides so that the Fe-Ti oxides did not experience intense dynamic recrystallization. Instead, the relatively high temperature and water-rich condition facilitated the operation of static recrystallization, resulting in the straight or smoothly curved grain boundaries of Fe-Ti oxides. The neighbor-pair misorientation patterns of Fe-Ti oxides show the preference for low-angle misorientation, supporting the idea that adjacent crystallized Fe-Ti oxides were rotated to coincident orientation in a melt. This study provides new microstructural evidence for the presence of immiscible Fe-rich melt from which the Fe-Ti oxides crystallized to form the net-textured ores. [ABSTRACT FROM AUTHOR]

• Ti 3 C 2 T x -ZnFe 2 O 4 was synthesized successfully with the ultrasonic dispersion method. • The response of 10 wt% Ti 3 C 2 T x -ZnFe 2 O 4 to 100 ppm acetone higher than pure ZnFe 2 O 4. • The optimum operating temperature of 10 wt% Ti 3 C 2 T x -ZnFe 2 O 4 was only 25 °C. In this work, a series of Ti 3 C 2 T x -ZnFe 2 O 4 composites were prepared by ultrasonic dispersion method. X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, etc., were used to characterize the obtained samples. Furthermore, the acetone sensing properties of Ti 3 C 2 T x -ZnFe 2 O 4 composites were investigated. According to the result, the 10 wt% Ti 3 C 2 T x -ZnFe 2 O 4 composite had a higher response (R a /R g = 28.7) to 100 ppm acetone than pure ZnFe 2 O 4 (R a /R g = 1.2) at room temperature. Meanwhile, the gas sensing selectivity towards acetone was improved. [ABSTRACT FROM AUTHOR]

[Display omitted] • CGss in massive ores contain high PGE relative to BMS. • Irarsite grains enclosed within the CGss were formed by exsolution. • Pd-bearing PGMs were developed due to hydrothermal alteration. The Ban Phuc Ni-Cu-(PGE) sulfide deposit in northern Vietnam contains no or few platinum-group minerals (PGM) in massive sulfide ores, and most PGM grains occur in altered disseminated sulfide ores, including sperrylite (PtAs 2), irarsite-orarsite-hollingworthite [IrAsS, OsAsS, (Rh,Ir)AsS], and froodite-sobolevskite-sudburyite [PdBi 2 , PdBi, Pd(SbBi) and PdSb]. Discrete PGM grains are enclosed within serpentines and base metal sulfides (BMS) of the disseminated ores. In contrast, small amounts (0.004 vol%) of cobaltite-gersdorffite solid solution (CGss) in massive sulfide ores commonly contain high PGE concentrations relative to the BMS. Textural relationships reveal that the CGss grains crystallize earlier than the host BMS in massive sulfide ores. The CGss grains are found to contain all six PGE and act as the major hosts for the PGE in the massive sulfide ores. The fast Fourier transform (FFT) patterns of high resolution TEM images show that the irarsite (IrAsS) enclosed within the CGss shares the same zone axis of ( 2 ¯ 1 2 ¯ ), which results from the exsolution of irarsite from the CGss. On the other hand, the CGss grains without visible PGM show an even distribution of PGE in the crystal and respective FFT patterns of CGss crystals. This is an example of a growing number of cases that massive sulfide ores have been found to contain PGE in As-bearing minerals, either PGM including sperrylite and members of the irarsite-orarsite-hollingworthite solid solution series or CGss. These results argue that PGE in the sulfide melt may enter the CGss at high temperature before the crystallization of monosulfide solution, rather than soluble in BMS, even if the sulfide melt was not As-saturated. [ABSTRACT FROM AUTHOR]

[Display omitted] • The platinum group minerals in Hongge layered intrusion are systematically investigated for the first time. • The PGM can crystallize directly from silicate melt or from Pd-bearing Bi (Te, Sb) melts in S-undersaturated mafic magmas. • TABS play a crucial role in PGE mineralization, either by direct crystallization as sperrylite or precipitation as Pd-bearing Bi (Te, Sb) melts. Platinum-group elements (PGEs) are typically hosted in the base metal sulfides (BMS) and platinum-group minerals (PGMs) of magmatic Ni-Cu-(PGE) sulfide deposits. The PGM may crystallize directly from sulfide melt, via exsolution from the BMS on sub-solidus cooling or recrystallization from them during metamorphism and hydrothermal overprints. Nevertheless, the distribution and origin of the major species of PGMs in S-poor mafic-ultramafic rocks, e.g. , many layered intrusions hosting Fe-Ti-V-Cr oxide deposits, remain unclear. The origin of PGMs in these rocks can be determined by their paragenesis and crystallographic orientations. Here, we systematically investigate the major species of PGMs in the Hongge layered intrusion (SW China), and examine the distribution of PGMs and the orientation relationships between PGMs and host minerals using the FIB-HRTEM techniques. A total of 52 grains of PGMs are identified from the olivine clinopyroxenite of the lower zone and Fe-Ti oxide-bearing olivine clinopyoxenite in the middle zone of the intrusion. They mainly include Pt-arsenide and Pd(Bi,Te,Sb) compounds. Pt-arsenide mainly occurs as discrete euhedral sperrylite (PtAs 2). The TEM analyses reveal that sperrylite and adjacent pyrrhotite have no specific crystallographic orientation relationships and form incoherent grain boundaries at their contact, indicating that the euhedral sperrylite likely crystallized directly from silicate melt and attached to the BMS and other coexisting minerals, rather than exsolved from precursor PGE-bearing BMS. The Pd(Bi,Te,Sb) compounds present as anhedral grains of froodite (PdBi 2), sobolevskite [Pd(Bi,Te)], merenskyite (PdTe 2), and stibiopalladinite (Pd 5 Sb 2). These grains are either enclosed within, attached to, or interstitial to the BMS, Fe-Ti oxides and silicates, suggesting that they were unlikely exsolved solely from PGE-bearing BMS. The HRTEM images reveal that the anhedral Pd(Bi,Te,Sb) compounds can be monocrystals or polycrystal. Monocrystal Pd(Bi,Te,Sb) compounds were not subjected to post-crystallization modification, and polycrystal Pd(Bi,Te,Sb) compounds are composed of numerous randomly distributed crystals. Given the anhedral grain shape, it is likely that the Pd(Bi,Te,Sb) compounds can crystallize to form different types of Pd-bearing PGMs from early precipitated Pd-bearing Bi(Te,Sb) melts. This study shows that the presence of Te, As, Bi, Sb and Sn (TABS) can play a crucial role in scavenging PGEs from S-undersaturated mafic magmas. Being long neglected, discrete PGMs, rather than PGE-bearing BMS, are likely the major endowment of PGEs in the Hongge layered intrusion. [ABSTRACT FROM AUTHOR]

Spinel oxides with specific morphology are importantly multifunctional materials for various applications. Here we report various morphological spinel oxides with one and two-modal pore size structures. The surface microstructure, phase composition, specific surface areas and electrocatalytic OER/ORR activities are examined. The results reveal that the bicomponent (NiCo 2 O 4 and Co 3 O 4) spinel exhibits a bimodal pore size distribution, high specific surface area, good OER activity (an overpotential of 313 mV at 10 mA cm−2 Geo) and low Tafel slope of 73.1 mV dec−1. The Co 3 O 4 component presents a perforated sheet morphology similar to an ancient window configuration with regular hole patterns, which benefits for mass transfer and O 2 bubble detachment. By comparison, the single-component NiCo 2 O 4 spinel having the morphology of more open self-assembled nanoneedle spheres or nanorod clusters, similar to the configuration of fish gill filaments, shows better ORR activities. The morphology, similar to the fish gills, can readily capture dissolved oxygen molecules from the film electrolyte at the three-phase interface and improve ORR performance. In addition, calcination temperatures also significantly affect pore structure, surface areas, and electrocatalytic activities. Finally, small Lab size Zn-air cells are assembled using thin flexible air electrodes with the self-assembled nanoneedle NiCo 2 O 4 catalysts. Electrochemical charging-discharging performance and cycling durability are evaluated. [Display omitted] • NiCo 2 O 4 spinel of various morphologies is prepared by template-free hydrothermal or coprecipitation and then calcination. • A bimodal pore size distribution in combination of a perforated sheet morphology benefits for enhancing OER activity. • Self-assembled nanoneedles or nanorods, similar to the configuration of gill filaments, exhibit better ORR performance. • Flexible Zn-air cells are assembled and electrochemical performance is evaluated. [ABSTRACT FROM AUTHOR]

In this work, hot gas filters composed of polyimide nanofiber membrane sandwiched between carbon woven fabrics are fabricated to capture fine particles of PM 2.5 level. Polyimide (PI) nanofibers with an average diameter of 190 nm are electrospun on supporting carbon fabrics as filtration layers. The filtration performance tests show that the maximum filtration efficiency reaches 99.99% for PM 2.5, while the maximum pressure drop is only 251.86 Pa after continuously testing for 25 min under a constant flow rate of 20 L/min. As the areal density of the PI nanofiber membrane increases, the filtration efficiency increases first and then levels off when the areal density reaches 11.64 g/m 2 . In regeneration performance test with back air flush at a pressure of 500 KPa, the composite filter maintains a filtration efficiency of 99.99% and a pressure drop of about 410 Pa. After heat treatment at 260 and 300 °C, the composite filter shows a relatively high filtration efficiency while the tensile strength of the carbon fabric does not change significantly. [ABSTRACT FROM AUTHOR]

Manufacturing stable and thin air electrodes for flexible Zn-air batteries becomes increasingly important and remains challenge. Here, we report low-cost mechanical calendering to fabricate thin gas-diffusion layers (GDL), catalytic layers (CL) and then heat pressing together. Finally, cylindrical and other sizes of flexible air electrodes are produced without the use of commercially expensive carbon cloth or carbon papers. By assembling the flexible air cathodes with anode Zn-In-Bi alloy powders or Zn foils, alkaline gel electrolytes and membranes, two kinds of Zn-air cells are assembled for performance evaluation. Results reveal that the LR6 Zn-air cells show a capacity of 5300–5400 mAh and an energy density of 340 Wh·kg−1 at 100 mA, having a double discharge capacity compared to the same size alkaline ZnMnO 2 cells. Under a high drain rate of 1000 mA, the capacity and utilization of the Zn alloy powder remain 2750 mAh and 372 mAh·g−1, respectively. The flexible pouch Zn-air cells exhibit excellent charge-discharge performance under conditions of each cycle with 10 min at 2 mA cm−2. The discharge voltage is maintained in the range of 1.25–1.30 V within 120 cycles while the charge voltage is 2.00–2.05 V. These results demonstrate that the thin air cathodes can satisfy the high bending requirements for cylindrical LR6 size cells and flexible pouch Zn-air cells, as well as have high mechanical stability and electrochemical performance. Electrochemical impedance spectroscopies of the air cathodes and Zn-air cells are also examined. [Display omitted] • Thin flexible air cathodes are prepared via calendaring and heat pressing without including commercial carbon cloth/papers. • The air cathodes show good ORR activities with nano NiCo 2 O 4 catalysts having close four-electron-transfer mechanism. • LR6 Zn-air cells exhibit excellent discharge profiles with a capacity of 5300-5400 mAh and energy density of 340 Wh kg-1. • Pouch Zn-air cells with flexible air cathodes show good charging-discharging performance at 2 mA cm-2. [ABSTRACT FROM AUTHOR]

Rationale: While morphine has important therapeutic value it is also one of the most widely abused drugs in the world. As a newly discovered style of cell death, ferroptosis is involved in the occurrence and development of many diseases, however, the current understanding of the relationship between ferroptosis and morphine is still limited. Objective: To clarify the role of opioid receptors in morphine-induced ferroptosis and to investigate the role of NRF2 in morphine-induced ferroptosis. Methods: We first used different doses of morphine (0, 0.5, 1, and 1.5 mM) to investigate morphine-induced ferroptosis in SH-SY5Y cells, and we choose 1.5 mM morphine for subsequent experiments. We next inhibited opioid receptors and NRF2 separately and examined their influence on morphine-induced ferroptosis. Finally, we tested morphine-induced insufficient autophagy. Results: Morphine triggered ferroptosis in a dose-dependent manner, which could be significantly rescued by the ferroptosis-specific inhibitor DFO. Moreover, GPX4 rather than xCT antiporter might be involved in morphine-induced ferroptosis. We also found naloxone could inhibit morphine-induced ferroptosis. Interestingly, our results demonstrated that NRF2 could promote rather than defend morphine-induced ferroptosis; this may be due to the increased p62-related insufficient autophagy. Conclusion: Morphine-induced ferroptosis is regulated by the opioid receptor and GPX4 rather than the xCT antiporter. NRF2-mediated ferroptosis in morphine-exposed cells may stem from increased p62-related insufficient autophagy. [ABSTRACT FROM AUTHOR]

Face to the limited repair capability of cartilage, we intended to find out signaling responsible for its matrix synthesis. Since spontaneous calcium response likes a label of cell status, here it was mapped in fresh and 24 hr cultured in situ chondrocytes under oxygen tensions of 20%, 5%, and 1% as well as mimic hypoxia conditions. The calcium source was traced using ethylene glycol‐bis (β‐aminoethyl ether)‐N,N,N′,N′‐tetraacetic acid (EGTA) and thapsigargin (TG) to treat cartilage. Their relative matrix of type II collagen (COLL‐II) and glycosaminoglycan (GAG) were quantified after cultured for 3 and 7 days. We disclosed the specific fingerprint of calcium response and matrix deposition along the histological zones under various oxygen tensions, from which the effects of hyperoxia, normoxia, and hypoxia conditions on as well as the optimal oxygen tensions for maintenance of various zones of cartilage or chondrocytes were derived and obtained. Our results revealed that cytoplasm calcium was conducive to synthesize COLL‐II but detrimental to synthesize GAG. These results provide correlation in addition to details of intracellular calcium response and matrix deposition in in situ cartilage along its histological zones under physiological oxygen tensions. [ABSTRACT FROM AUTHOR]

Background. Realgar was usually selected as a substitute for arsenic trioxide to treat acute promyelocytic leukemia due to its higher effect without high cardiotoxicity. In traditional Chinese medicine (TCM), realgar is usually processed by the water-grinding method clinically, but the mechanism of realgar processing detoxification is still unclear. However, it is necessary to take safety and efficacy into account while evaluating a drug. Methods. Sixty male Wistar rats were divided into control group, realgar products-treated groups, and corresponding subgroups. Biochemistry analysis and histopathological examination were performed in the study, and plasma samples were collected from all the rats for metabolomics analysis. Results. No significant toxicity was observed in rats treated with 0.64 g/kg/day grinding realgar (G-r) and water-grinding realgar (WG-r). When the dose increased to 1.92 g/kg/day, the liver weight coefficients of the rats treated with G-r (HG-r: 3.65 ± 0.26%) and WG-r (HWG-r: 3.67 ± 0.14%) increased significantly and severe hepatic injury occurred in comparison to the control group (Group C: 3.00 ± 0.21%). After one week's withdrawal, the liver injury caused by the high dose of WG-r significantly recovered, while the liver damage caused by G-r was more difficult to recover. In metabolomics analysis, 14 metabolites were identified as the potential biomarkers in realgar-treated rats. These metabolites indicated that there were perturbations of the primary bile acid biosynthesis, arachidonic acid metabolism, linoleic acid metabolism, and glycerophospholipid metabolism in the realgar-treated groups. Conclusions. These results illustrate that, as a TCM processing method, water grinding had the effect of reducing toxicity, and the metabolomics method may be a valuable tool for studying the toxicity induced by TCM and the mechanism of TCM processing. [ABSTRACT FROM AUTHOR]

We have previously demonstrated that the rate of fluid shear stress (ΔSS) can manipulate the fate of mesenchymal stem cells (MSCs) to osteogenic or chondrogenic cells. However, whether ΔSS is comparable to other two means of induction medium and substrate stiffness that have been proven to be potent in differentiation control is unknown. In this study, we subjected MSCs to 1–7 days of osteogenic or chondrogenic chemical induction, or 1–4 days of 37 or 86 kPa of substrate stiffness induction, followed by 20 min of Fast ΔSS (0–0′) or Slow ΔSS (0–2′), which is a laminar FSS that linearly increased from 0 to 10 dyn/cm 2 in 0 (Fast) or 2 min (Slow) and maintained at 10 dyn/cm 2 for a total of 20 min. We found that 20 min of ΔSS could compete with 5 days' chemical and 2 days' substrate stiffness inductions. Our study confirmed that ΔSS is a powerful tool to control the differentiation of MSCs, which stressed the possible application in MSCs linage specification. [ABSTRACT FROM AUTHOR]