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In this study, thin Cu 2 O films were first produced on a Cu foil by cathodic electro-deposition at different pH values. Then the Cu 2 O side of the Cu foil was closely attached to an Al 2 O 3 ceramic substrate and heated to 1075 °C under N 2 atmosphere. The effect of the pH value on the microstructure of the Cu 2 O film was investigated by scanning electron microscopy (SEM). The shape of the Cu 2 O grains changed from a 4-sided pyramid to a triangular prism to a 3-faced pyramid when increasing the pH value from 9 to 11 and 12, respectively. The X-ray diffraction (XRD) results showed that both CuAlO 2 and CuAl 2 O 4 were formed at the Cu/Al 2 O 3 interface after reacting for 4 h, in contrast to results reported in previous papers. When the bonding time was extended to 7 h, discontinuous interfacial reaction products were found on the cross-section of the Cu/Al 2 O 3 interface. The effect of the Cu 2 O morphology on the bonding strength of the Cu/Al 2 O 3 was discussed considering the results of the flexural strength tests, and the results indicated that a uniform and dense Cu 2 O morphology would be beneficial for improving the bonding strength during the metallization process. [ABSTRACT FROM AUTHOR]

Although TiO 2 nanoparticles (NPs) exposure has been demonstrated to cross blood–testis barrier and accumulate in the testis resulting in the reduction of sperm numbers, limited data with respect to the molecular mechanism of decreased spermatogenesis caused by TiO 2 NP exposure. In this research, testicular damage, sperm number and alterations in testis-specific gene expressions in male mice induced by intragastric administration with TiO 2 NPs for six months were investigated. It was found out that TiO 2 NPs could migrate to cells, deposit in the testis and epididymis and thus cause damages to relevant organs, which are, to be more specific, the reductions of total sperm concentrations and sperm motility and an enhancement in the number of abnormal sperms in the cauda epididymis. Furthermore, the individual expression regarding to the mRNAs and proteins of testis-specific genes, including Cdc2, Cyclin B1, Dmcl, TERT, Tesmin, TESP-1, XPD and XRCCI, were significantly declined, whereas Gsk3-β and PGAM4 expressions were greatly elevated in mouse testis due to the exposures, which in fact implied that the reduced spermatogenesis may be involved in the alternated testis-specific gene expressions in those exposed male mice. [ABSTRACT FROM AUTHOR]

Oxy-coal combustion produces a combustion environment that contains large amounts of CO 2 , H 2 O compared to conventional air combustion. Silica (SiO 2 ) is a major component of the mineral impurities in coal and the vaporization of silicon containing species controls the initial phase of formation of ultrafine particulate matter (ultrafine PM) via vaporization–condensation mechanism. To investigate the vaporization behavior of silica in wet recycle oxy-coal combustion conditions, synthetic chars with SiO 2 inclusions were burned at 1873 K in the O 2 /CO 2 /H 2 O environments with steam of up to 10 vol.%. Experiments were carried out with a high temperature drop tube furnace (HDTF) system and ultrafine PM was collected with a low pressure impactor (LPI). Meanwhile, modeling work was carried out for further investigation of the effect of H 2 O on the vaporization of silica. The improved model was developed based on a model built in conventional air combustion conditions and verified by the experiment. The results indicate that, under the wet recycle oxy-coal combustion conditions, H 2 O in combustion atmosphere significantly enhanced the vaporization of SiO 2 and considerably increased the yield of the ultrafine PM. The variation of char combustion characteristics such as burning temperature and gas properties surrounding the mineral inclusions caused by H 2 O seemed to be the primary cause. Especially, effect of H 2 inside the char particle cannot be ignored. [ABSTRACT FROM AUTHOR]

The influence of blueberry anthocyanins-enriched extracts (BAE) on cyclophosphamide (CTX)-induced lung damage was investigated. BAE (20 and 80 mg/kg/d) were orally dosed to rats 7 d both before and after CTX administration (100 mg/kg, intraperitoneal injection, single dose). The results showed CTX treatment induced obvious pathological pulmonary injury with raised injury score and lung/body weight ratio. In CTX group, the activity of lysosomal proteases, lung permeability and the number of neutrophil infiltrates all elevated. On the other hand, claudin-4 and zonula occluden-1 protein levels decreased. And also changes of oxidative stress and inflammatory cytokines parameters together with nuclear factor-κB activation were shown. Improvement of all above-mentioned physiological and biochemical parameters was exhibited in BAE groups, with a dose-dependent manner. In conclusion, BAE attenuate the CTX-induced lung toxicity, antioxidant and anti-inflammatory characteristics are involved in the protective mechanism of BAE. [ABSTRACT FROM AUTHOR]

This article reports the chemical deposition of silver shells on the surface of micro-carbon spheres. The structure, morphology and composition were characterized by scanning electron microscopy and X-ray diffraction. Carbon spheres were oxidized with concentrated nitric acid and sulfuric acid for the surface hydrophilic modifier. Subsequently Carbon spheres were coupled with KH-550 in order to grafting NH2 groups, which is important to the site-selective deposition of silver during sensitization and activation process. The dispersible Ag/C core-shell composite could be systematically controlled through adding appropriate PVP and adjusting modest pH value in the deposition process. The XRD and SEM results show that the silver particles can completely coat the carbon spheres and the particle size of the silver shell on the surface of carbon core is 24.8 nm. [ABSTRACT FROM AUTHOR]

Purpose Observe how specific small RNA interference (siRNA) aimed at TPX2 gene suppresses TPX2 gene expression in esophageal cancer EC9706 cells and the effect on esophageal cancer cell growth and invasion ability. Methods Transfect TPX2 siRNA into EC9706 cells via lipofectamin 2000. The experiments were divided into three groups, a negative control, a blank control and an siRNA interference group (24 h, 48 h, 72 h, 96 h). We examined RNA and protein level alteration of the TPX2 gene after TPX2 siRNA transfection by RT-PCR and Western blot analysis. Detection of how TPX2 siRNA influences EC9706 cell proliferation was done by MTT, cell apoptosis monitored through Tunel assay, in vitro invasion ability via Boyden chamber and cell cycle change by flow cytometry. Results After effective siRNA transfection, TPX2 mRNA and protein expression level in siRNA interference group were (0.31 ± 0.08, 0.39 ± 0.12),72 h after transfection, significantly lower than blank control group (1.00 ± 0.01) and negative control group (0.98 ± 0.11), ( F = 71.182, t 1 = 8.17, t 2 = 7.90, P < 0.05); MTT results demonstrated that cell growth and proliferation were inhibited and the inhibition rate was up to 35.4% ( P < 0.05) compared with the control group. TUNEL results indicated that cell apoptosis index in siRNA interference group was 18.28 ± 0.35, higher than that in blank control group (4.07 ± 0.26)and negative control group (4.13 ± 0.22), ( F = 244.5, t 1 = 60.61, t 2 = 53.32, P < 0.01). Boyden chamber results showed that the transmembrane cell number was 45.30 ± 8.08 in siRNA interference group, less than blank control group (121.90 ± 7.83), ( F = 122.46, t 1 = 11.81, t 2 = 10.47, P < 0.01); besides, in siRNA interference group cell invasion inhibition rate was 71.42 ± 9.12, higher than negative control group (5.65 ± 3.55), ( t = 14.256, P < 0.01). Flow cytometry results illustrated that more EC9706 cells went into apoptosis and cell cycle arrested in S phase. Similar results were obtained by in vivo transplantation, as TPX2 siRNA transfection significantly reduced tumor growth of the xenograft in nude mice. Conclusion siRNA could effectively inhibit the invasion and metastasis of EC9706 cells, promote the apoptosis of tumor cells and may become a new approach for treatment of esophageal carcinoma. [ABSTRACT FROM AUTHOR]

Highlights: [•] Phoxim exposure resulted in decrease of the cocooning rate of B. mori. [•] TiO2 NPs could increase the cocooning rate of B. mori under phoxim toxicity. [•] Phoxim exposure damaged silk gland and decreased Fib-L, Ser2, Ser3, and P25 expressions. [•] TiO2 NPs could relieve silk gland damage and increase Fib-L, Ser2, Ser3, and P25 expressions. [Copyright &y& Elsevier]

Highlights: [•] Recovery property of the device parameters under step-stress is investigated. [•] The maximum output current can recover almost completely after stress. [•] Recovery property can be explained by the trapping and de-trapping procedures. [•] The de-trapping activation energy was evaluated to be 0.30eV. [•] No pits or cracks under the gate contact were found after stress. [Copyright &y& Elsevier]

Highlights: [•] The sodium aluminosilicate plays an important role in PM2.5 reduction by kaolin. [•] The capability of kaolin to reduce PM2.5 depends on the sodium occurrence in coals. [•] The effect of kaolin on PM2.5 reduction becomes weaker during O2/CO2 combustion. [•] Particle collision may be taken into consideration for PM2.5 reduction. [Copyright &y& Elsevier]

Highlights: [•] Exposure to lanthanides impaired renal function in mice. [•] Exposure to lanthanides induced cell necrosis in kidney. [•] Exposure to lanthanides promoted ROS accumulation in kidney. [•] Exposure to lanthanides caused the reduction of antioxidant capacity in kidney. [•] The order of kidney damages was Ce exposure>Nd exposure>La exposure. [Copyright &y& Elsevier]

Highlights: [•] Exposure to TiO2 NPs could cross blood–testis barrier and be accumulated in testis. [•] Exposure to TiO2 NPs caused testis and sperm lesions in male mice. [•] Exposure to TiO2 NP decreased sperm numbers and sperm motility in male mice. [•] Exposure to TiO2 NP resulted in imbalance of sex hormones in male mice. [•] Exposure to TiO2 NP caused alteration of 142 genes expression of known function in testis. [ABSTRACT FROM AUTHOR]

Abstract: Numerous studies have demonstrated that the brain is one of the target organs in acute or chronic titanium dioxide (TiO2) nanoparticles (NPs) toxicity, and oxidative stress plays an important role in this process. However, whether brain oxidative injury responds to TiO2 NPs by activating the P38-nuclear factor-E2-related factor-2 (Nrf-2) pathway is not fully understood. The present study aimed to examine activation of the P38-Nrf-2 signaling pathway associated with oxidative stress in the mouse brain induced by intranasal administration of TiO2 NPs for 90 consecutive days. Our findings indicate that TiO2 NPs caused overproliferation of spongiocytes and hemorrhage in the mouse brain. Furthermore, TiO2 NPs significantly activated p38, c-Jun N-terminal kinase, nuclear factor kappa B, Nrf-2 and heme oxygenase-1 expression in the brain, which in turn, led to increased production of reactive oxygen species, as well as lipid, protein and DNA peroxidation. These findings suggest that TiO2 NPs-induced oxidative damage in the mouse brain may occur via the p38-Nrf-2 signaling pathway. Therefore, application of TiO2 NPs in the environment should be performed with caution. [Copyright &y& Elsevier]

• PES is first time used to modify the li electrode which shows excellent lithium affinity. • PES film with polar functional groups (O = S = O) can realize the redistribution of the lithium ion flow and a uniform nano-columnar lithium layer can be obtained even in the high current density of 5 mA cm−2. • (3) the PES film prolongs the half-cell life three times than control group with higher coulombic efficiency. The dendrite problem and low Coulombic efficiency of lithium anode have hindered its commercial application for long time. In this paper, the Polyethersulfone (PES) film is spin-coated to construct a composite lithium anode. With the polar functional groups of PES, the lithiophilicity of the anode is greatly improved. Non-conductive uniform structure with polar functional groups (O = S = O) constructed on the lithium metal anode can realize the redistribution of the lithium ion flow and reduce the probability of dendrite formation in the "hot spot" area. A uniform nano-columnar lithium layer can be obtained even in the high current density of 5 mA cm−2. Electrochemical interface studies have illustrated that PES film can increase the migration speed of lithium ion among the electrodes, increase the reduction reaction rate of lithium ion. Finite element simulation calculations show that the PES film can effectively reduce the concentration of lithium ion near the dendrite tip. In addition, with the Cu-PES structure modified by 3.3 mg mL−1 PES, the average Coulombic efficiency of half-cell reaches 90%, and the cell can run for 220 cycles stably which is three times than control group in 0.5 mA cm−2. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Although numerous studies have described the accumulation of titanium dioxide nanoparticles (TiO2 NPs) in the liver, kidneys, lung, spleen, and brain, and the corresponding damage, it is unclear whether or not TiO2 NPs can be translocated to the ovary and cause ovarian injury, thus impairing fertility. In the current study, ovarian injury and gene-expressed characteristics in female mice induced by intragastric administration of TiO2 NPs (10mg/kg) for 90 consecutive days were investigated. Our findings indicated that TiO2 NPs can accumulate in the ovary and result in ovarian damage, cause an imbalance of mineral element distribution and sex hormones, decrease fertility or the pregnancy rate and oxidative stress in mice. Microarray analysis showed that in ovaries from mice treated with TiO2 NPs compared to controls, 223 genes of known function were up-regulated, while 65 ovarian genes were down-regulated. The increased expression of Cyp17a1 following TiO2 NPs treatment suggested that the increase in estradiol biosynthesis may be a consequence of increased TiO2 NPs. In addition, the elevated expression of Akr1c18 implied that progesterone metabolism was accelerated, thus causing a decrease in the progesterone concentration. Taken together, the apparent regulation of key ovarian genes supports the hypothesis that TiO2 NPs directly affects ovarian function. [Copyright &y& Elsevier]

Abstract: Exposure to titanium dioxide nanoparticles (TiO2 NPs) has been demonstrated to result in pulmonary inflammation in animals; however, very little is known about the molecular mechanisms of pulmonary injury due to TiO2 NPs exposure. The aim of this study was to evaluate the oxidative stress and molecular mechanism associated with pulmonary inflammation in chronic lung toxicity caused by the intratracheal instillation of TiO2 NPs for 90 consecutive days in mice. Our findings suggest that TiO2 NPs are significantly accumulated in the lung, leading to an obvious increase in lung indices, inflammation and bleeding in the lung. Exposure to TiO2 NPs significantly increased the accumulation of reactive oxygen species and the level of lipid peroxidation, and decreased antioxidant capacity in the lung. Furthermore, TiO2 NPs exposure activated nuclear factor-κB, increased the levels of tumor necrosis factor-α, cyclooxygenase-2, heme oxygenase-1, interleukin-2, interleukin-4, interleukin-6, interleukin-8, interleukin-10, interleukin-18, interleukin-1β, and CYP1A1 expression. However, TiO2 NPs exposure decreased NF-κB-inhibiting factor and heat shock protein 70 expression. Our results suggest that the generation of pulmonary inflammation caused by TiO2 NPs in mice is closely related to oxidative stress and the expression of inflammatory cytokines. [Copyright &y& Elsevier]

Abstract: An essential aspect of tooth tissue engineering is the identification of suitable scaffolding materials to support cell growth and tissue regeneration. Treated dentin matrix (TDM) from a rat has recently been shown to be a suitable scaffold for rat dentin regeneration. However, due to species-specific differences, it remains unclear whether a similar fabrication method can be extended to human TDM and human dentin regeneration. Therefore, this present study explored the biological response to a human TDM (hTDM) created using a modified dentin treatment method. Various biological characteristics, including cell proliferation, cell migration, cell viability, and cytotoxity were investigated. To assess the inductive capacity of hTDM, dental follicle cells (DFCs) were combined with hTDM and were implanted in vivo for 8 weeks in a mouse model. The resulting grafts were studied histologically. The results showed hTDM released dentinogenic factors, indicating that hTDM could play a sustained role in odontogenesis. DFC attachment, growth, viability, and cytotoxicity on the surface of hTDM showed a notable improvement over those on calcium phosphate controls. Most importantly, in vivo hTDM induced and supported regeneration of complete dentin tissues, which expressed dentin markers DSP and DMP-1. As cells in and around the regenerated dentin were positive for human mitochondria, implanted DFCs and hTDM were responsible for the regenerated dentin tissues. In conclusion, hTDM is indicated as an ideal biomaterial for human dentin regeneration. [Copyright &y& Elsevier]

The biotransformation of arsenic mediated by microorganisms plays an important role in the arsenic biogeochemical cycle. However, the fate and biotransformation of arsenic in different soil fauna gut microbiota are largely unknown. Herein the effects of arsenic contamination on five types of soil fauna were compared by examining variations in arsenic bioaccumulation, gut microbiota, and arsenic biotransformation genes (ABGs). Significant difference was observed in the arsenic bioaccumulation across several fauna body tissues, and Metaphire californica had the highest arsenic bioaccumulation, with a value of 107 ± 1.41 mg kg−1. Arsenic exposure significantly altered overall patterns of ABGs; however, dominant genes involved in arsenic redox and other genes involved in arsenic methylation and demethylation were not significantly changed across animals. Except for M. californica , the abundance of ABGs in other animal guts firstly increased and then decreased with increasing arsenic concentrations. In addition, exposure of soil fauna to arsenic led to shifts in the unique gut-associated bacterial community, but the magnitude of these changes varied significantly across ecological groups of soil fauna. A good correlation between the gut bacterial communities and ABG profiles was observed, suggesting that gut microbiota plays important roles in the biotransformation of arsenic. Overall, these results provide a universal profiling of a microbial community capable of arsenic biotransformation in different fauna guts. Considering the global distribution of soil fauna in the terrestrial ecosystem, this finding broadens our understanding of the hidden role of soil fauna in the arsenic bioaccumulation and biogeochemical cycle. [Display omitted] • Arsenic bioaccumulation exhibited significant differences among different soil fauna. • Both bacterial communities and arsenic biotransformation genes shifted in different fauna guts. • Streptomycetaceae , Chthoniobacter, Bradyrhizobiaceae, Enterobacteriaceae as indicator species for arsenic were observed. [ABSTRACT FROM AUTHOR]

Lithium dendrite growth has long been regarded as the main obstacle for the practical usage of lithium metal battery. In this paper, we heat-treat the copper collector at a low temperature to prepare a Cu x O (x = 1–2)/Cu composite electrode. The samples heat-treated at 250 °C are mainly composed of Cu 2 O confirmed by X-ray photoelectron spectroscopy (XPS) analysis, which has the best wettability with propylene carbonate (PC)-based electrolyte. The as-prepared Li–Cu cell (composite electrode) can run more than 150 cycles. However, boric acid additive can prolong the cycle number of Li–Cu cell to more than 300 cycles at a current density of 0.5 mA cm−2 with a Coulombic efficiency larger than 85%. Scanning electron microscopy (SEM) image shows that the Cu 2 O/Cu composite electrode with boric acid additive in the electrolyte can inhibit the formation of lithium dendrite on the surface of the electrode, and a uniform and dense nano-columnar lithium layer can be obtained even at 5 mA cm−2. The synergistic effect is attributed to the improved interfacial properties for Cu 2 O/Cu composite collectors when boric acid (BA) is used as additives. Image 1 • A simple method was used to prepare the composite collector of Cu 2 O. • The collaboration of Cu 2 O with boric acid can inhibit lithium dendrite in 5 mA cm−2. • The synergistic effect prolongs the half-cell life with higher coulombic efficiency. [ABSTRACT FROM AUTHOR]

• An innovative ZIF-derived 2D leaf-like bimetallic (Co, Zn) doped porous carbon nanocomposite (BPCN) has been fabricated successfully via simple aqueous synthesis followed by subsequent heat treatment at 650 °C under N 2 atmosphere. • The 2D leaf-like BPCNs possess improved interfacial polarization and impedance matching. • The leaf-like BPCN composites exhibit broadband microwave absorption properties. Two-dimensional (2D) carbon matrix nanocomposites are promising for efficient microwave absorption on account of the large specific surface area, the small size effect of nanoparticles and the multiple attenuation mechanisms to electromagnetic waves. Herein, we prepared innovative two-dimensional leaf-like bimetallic (Co, Zn) doped porous carbon nanocomposites (BPCNs) via a simple aqueous-phase self-assembly process and subsequent heat treatment. An in-depth study of the relative metal content on the leaf-like morphology, porous structure and microwave absorption properties has been carried out in detail. The research results show that the BPCNs possess large surface areas and abundant mesoporous, and metallic nanoparticles can be well dispersed in the carbon skeleton after high-temperature calcination. Moreover, the BPCNs exhibited excellent microwave absorption properties with the maximum effective absorption bandwidth (EAB) of 5.7 GHz at the thickness of 2.5 mm when Co relative content increased to 40% (BPCN-0.4), and the minimum reflection loss (RL) can reach to −45.2 dB. The broad EAB and strong RL value can be attributed to the small size effect of Co and Zn nanoparticles, the improved interfacial polarization and the optimized impedance matching. Considering that, the 2D leaf-like BPCNs can be an innovative candidate as lightweight and efficient microwave absorber. [ABSTRACT FROM AUTHOR]

• Danhong injection (DHI) treatment enhanced angiogenesis after myocardial infarction (MI). • DHI upregulated miR-126 expression in hypoxic endothelial cells and post-infarct hearts. • DHI enhanced the post-infarct angiogenesis after MI by activating the miR-126/ERK/VEGF pathway. Danhong injection (DHI) is a Chinese drug used for relieving cardiovascular diseases. This study aimed to identify the effect and mechanism of action of DHI on post-infarct angiogenesis, especially the epigenetic regulation of angiogenesis. A myocardial infarction (MI) mouse model was induced by ligating the left anterior descending coronary artery. A 4-week daily treatment with or without DHI via intraperitoneal injection was started immediately following MI. The changes in cardiac function, pathology, and angiogenesis following MI were measured by echocardiography and immunostaining. Matrigel tube formation and scratch wound assays were used to evaluate the effect of DHI on the proliferation and migration of hypoxic human umbilical vein endothelial cells (HUVECs). The expression of miR-126, Spred-1, and angiogenesis-related mRNAs was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The expression of related proteins and the phosphorylated levels of extracellular signal–regulated kinase (ERK) and protein kinase B were detected by Western blot analysis. The loss-of-function study was performed using antagomir-126. The DHI-treated mice had significantly reduced infarct area, improved ejection fraction, and increased capillary density 4 weeks after MI. Also, DHI promoted the proliferation and migration of hypoxic HUVECs. The qRT-PCR and Western blot analysis revealed that DHI intervention upregulated miR-126, suppressed Spred-1 expression, and activated the ERK pathway, but not the Akt pathway. The loss-of-function study showed the blockade of the pro-angiogenic effect of DHI by antagomir-126 involving the ERK/vascular endothelial growth factor (VEGF) pathway. DHI enhanced post-infarct angiogenesis after MI by activating the miR-126/ERK/VEGF pathway. [ABSTRACT FROM AUTHOR]