Ion Chelating Agent Research Articles

Metal ion chelation enhances tissue plasminogen activator (tPA)-induced thrombolysis: an in vitro and in vivo study.

Stroke is the third leading cause of death in the United States and the leading cause of adult disability. Despite enormous research efforts including many clinical trials, tissue plasminogen activator (tPA) remains the only FDA-approved treatment for acute ischemic stroke. Unfortunately, only 1-3% of stroke patients in the US receive this therapy because of the narrow time window and severe side effects for using tPA. The most deadly and damaging side effect is the risk of intracranial bleeding or hemorrhage. For that reason, the dose of tPA and its overall administration are under tight control, which may compromise the effect of thrombolysis. Studies have been focused on improving the effectiveness of tPA for higher rate of reperfusion, and the safety for less adverse bleeding episode. We studied how metal ions (zinc & iron) affect tPA-induced thrombolysis in vitro and in vivo, and proposed a method to improve the rate of thrombolysis. The amount of hemoglobin in the blood clot lysis was measured by a spectrophotometer. The tPA-induced thrombolysis was measured in vivo in femoral artery. Our results showed that Zn2+, Fe3+ and Fe2+ inhibited tPA-induced thrombolysis, with Zn2+ and Fe2+ being the most effective. Metal ion chelating agent EDTA when it was co-applied with tPA significantly enhanced the tPA-induced thrombolysis. The chelation alone did not have noticeable thrombolytic effect. In in vivo study of tPA-induced thrombosis following femoral artery thrombosis, the co-application of tPA and EDTA achieved significant higher rate of reperfusion than that by tPA treatment alone, suggesting that ion chelation facilitates tPA-induced thrombolysis and potentially improves the safety of tPA application by reducing the necessary dose of tPA application. Our results suggest that the co-application of a chelator and tPA improves the efficacy and, potentially, safety of tPA application, by reducing the necessary dose of tPA for thrombolysis.

Synthesis and properties of hydrophobically associating polymer fracturing fluid

The double tailed hydrophobic monomer PMB-16 was synthesized by the reaction of phenylethylamine,1-bromohexadecane and methacryloyl chloride. The ternary hydrophobic association polymer (PADM) was synthesized by free radical copolymerization of PMB-16 with acrylamide (AM) and methacryloyloxyethyl trimethylammonium chloride (DMC). The optimum synthesis conditions were as follows, the mass ratio of m (AM):m (DMC):m (PMB-16) was 80:19.6:0.4, the total monomer concentration was 35.0 wt%, the amount of initiator (V50) was 0.1 wt% of the total mass of monomer, the reaction temperature was 55 °C, the reaction time was 6.0 h, the system pH was 7, and the amount of metal ion chelating agent (EDTA-4Na) was 0.01 wt% of the total mass of monomer. The results of performance evaluation showed that PADM aqueous solution had excellent temperature and salt resistance. Using zirconium acetylacetonate as crosslinking agent, the mass crosslinking ratio of PADM solution to zirconium acetylacetonate was 100:0.9, the crosslinking temperature was 60 °C, and the pH value was 6.0. The system presented good thickening, temperature resistance, shear stability and low residue content, so it was a low damage fracturing fluid.

Preparation of Gd-Au Dendrimer-Entrapped Gold Nanoparticles-Folic Acid Nanoparticles and Its Application in Computed Tomography/Magnetic Resonance Imaging Dual-Modality Diagnosis of Abdominal Tumors

ABSTRACTThe development of nanomaterials, especially the development of multi-modality imaging nanoprobe technology has become a reality for tumor imaging diagnosis. In this study, the gadolinium ion chelating agent (2,2′,2′′-(10-(2-(2, 5-dioxopyrrolidin-1-oxyl)-2 oxoethyl)-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7-tri)triacetic acid) (DOTA-NHS) and polyethylene glycol (PEG)-modified targeting ligand PEG-folic acid (FA) were grafted onto the PEG-modified fifth-generation polyamide-amine dendrimer (P5-NH2), which were undertaken as standards to wrap gold nanoparticles. Then, remaining amino group was acetylated to acquire Gd–Au DENPS-FA nanoparticles. Biocompatibility and cytotoxicity of nanoparticles were analyzed while characterizing them. The cases with unidentified tumors (mass diameter >4.5 cm) of abdominal or pelvic origin were selected and used for clinical study of computed tomography (CT)/magnetic resonance imaging (MRI) dual-modality abdominal tumors. In the test, average particle size of Gd-Au DENPs-FA nanoparticles was 4.2 nm, and they had good water solubility and stability in aqueous solution. When concentration of Au+ nanoparticles increased, the cell morphology remained normal, only a small number of round cells appeared, and the cell activity remained above 80%. GD-Au DENPs-FA nanoparticles had a good targeting specificity for KB cells with high folate receptor expression. During 6–24 hours of injection, the signal at the tumor site of the patient was enhanced markedly, namely the targeted gold nanoparticles were bound to the tumor tissue and the metabolic rate was slow. Based on this material, CT/MRI imaging could be performed in the patient’s body and further used for the early diagnosis of abdominal tumors.

Structural modification and biological activities of carboxymethyl Pachymaran.

Polysaccharides are good chelating agents for metal ions, which are often used to synthesize polysaccharide metal ion complexes. With carboxymethyl pachymaran (CMP) as the substrate, carboxymethyl pachymaran iron (CMPF), carboxymethyl pachymaran selenium (CMPS), and carboxymethyl pachymaran zinc (CMPZ) were synthesized by response surface methodology, and their biological characteristics were studied. The results showed that the CMP was a β‐polysaccharide, and the degree of carboxymethylation was 0.6352. The polysaccharide metal ion complexes were characterized by physicochemical methods, scanning electron microscopy, Fourier transform infrared spectroscopy, circular dichroism spectroscopy, and nuclear magnetic resonance spectroscopy. All the polysaccharides and complexes possessed antioxidant activity in vitro with scavenging activities to ABTS, superoxide anions, and ferrous ions. CMPF, CMPS, and CMPZ caused significant inhibition of A2780 cell proliferation, promoted the production of reactive oxygen species, and induced apoptosis in a human ovarian cancer cell line (A2780 cells). These results suggest that the CMP complex may be an effective candidate drug for cancer treatment in the field of functional food and pharmacology.

Controllable preparation and performance of bio-based poly(lactic acid-iminodiacetic acid) as sustained-release Pb2+ chelating agent

SummaryThe bio-based lactic acid (LA) and the common metal ion chelating agent iminodiacetic acid (IDA) are used to design and prepare a polymeric sustained-release Pb2+ chelating agent by a brief one-step reaction. After the analysis on theoretical calculation for this reaction, poly(lactic acid-iminodiacetic acid) [P(LA-co-IDA)] with different monomer molar feed ratios is synthesized via direct melt polycondensation. P(LA-co-IDA) mainly has star-shaped structure, and some of them have two-core or three-core structure. Thus, a possible mechanism of the polymerization is proposed. The degradation rate of P(LA-co-IDA)s can reach 70% in 4 weeks. The change of IDA release rate is consistent with the trend of the degradation rate, and the good Pb2+ chelating performance is confirmed. P(LA-co-IDA) is expected to be developed as a lead poisoning treatment drug or Pb2+ adsorbent in the environment with long-lasting effect, and this research provides a new strategy for the development of such drugs.

Characteristics of Some Selected Methods of Rare Earth Elements Recovery from Coal Fly Ashes

The article covers the issues related to the characteristics, application, and some methods of rare earth elements (REEs) recovery from coal fly ashes. REEs are elements with growing demand and a very wide range of application, especially when it comes to modern technologies. The conducted analysis and price forecast proved the existing upward tendency, and this confirmed the need to search for new REE sources, among industrial waste (proecological effect). The development of the REE recovery technology would involve solving several problems related to REE speciation, optimization of factors controlling their extractivity and selection of the REE separation method from obtained extraction solutions with a very extreme pH and complicated composition. The paper presented advantages and disadvantages of usually used methods of REE separation from coal fly ashes, like physical and acid–base leaching. It was also presented alternative REE recovery techniques in the form of membrane and biological methods and based on ion liquids (ILs) or chelating agents. The directions of further modifications, which will allow the efficient REE recovery were presented. The aim of this article was to propose specific solutions based on the creation of appropriate multistage method of REE recovery. It will be a combination of magnetic and size separation, acid–base leaching (including roasting in justified cases), removal of matrix elements with ILs (Al, Si, and Fe), and finally REE membrane separation, allowing one to obtain the appropriate process efficiency.

Calcium signalling mediated the regulation of growth and polysaccharide accumulation by light quality in Dendrobium officinale protocorms

This study selected Dendrobium officinale protocorms as the experimental material and used different light-quality treatments and calcium signalling inhibitors to explore the mechanism of the biological response of calcium to light quality. The results indicate that a 1:3 red:blue (R:B) light ratio promotes the accumulation of biomass and polysaccharides in the protocorm. Nevertheless, this effect can be entirely counteracted by calmodulin (CaM) inhibitors and calcium ion-chelating agents. The possible mechanisms of this effect are as follows: (1) The Ca2+-CaM signal-regulated photosynthetic apparatus is improved by the R:B 1:3 light, increasing the CaM content and Ca2+-ATPase activity. Thus, R:B 1:3 light increases the development of the photosynthetic apparatus in the D. officinale protocorm, enhances its photosynthetic productivity, and promotes the activities of sucrose phosphatase; accordingly, biomass and sucrose accumulation increase. (2) R:B 1:3 light enhances Ca2+-CaM signalling and regulates glycometabolic processes to promote the activities of sucrose synthase, thus increasing fructose and glucose levels and providing sufficient synthetic precursors to promote polysaccharide production.

Synergistic effect of ion chelating agent and inorganic compound on pore structure, mechanical and self-healing performance of cement-based materials

Ion chelating agent can effectively improve the self-healing of concrete. In order to further enhance the self-healing ability of cement-based materials, ion chelating agent and inorganic compounds (sodium silicate and sodium bicarbonate) were used together in this paper. Pore size distribution, mechanical and self-healing performance of the mortars with ion chelating agent and inorganic compounds were investigated. The results showed that harmful pores (pore diameter above 0.1 μm) of the mortar was reduced and mechanical properties was increased by adding ion chelating agent and inorganic compounds, especially mortar mixed with 0.50% ion chelating agent and 0.25% sodium silicate had the least harmful pores and the highest compressive strength and flexural strength. Moreover, the self-healing properties of mortars were significantly improved by combination of ion chelating agent and inorganic compound. Especially for mortar mixed with 0.5% ion chelating agent and 0.5% sodium silicate, the relative water permeability coefficient decreased to 0 after curing for 28 d, and the cracks with width of 0.31 mm and 0.46 mm could be completely closed after curing for 3 d and 28 d respectively. SEM observation showed that the calcium carbonate, ettringite and calcium carbonate were covered by CSH gel in the cracks and interior of the mortar mixed with ion chelating agent and sodium silicate, which proved that the ion chelating agent and sodium silicate had synergistic effect on the self-healing properties of cement-based materials.

Synthesis of Novel 8‐cyclo‐1,5,3,7‐Diazadiphosphocine Derivatives Via [4 + 2] Cycloaddition

As part of our research program into pharmacologically valuable compounds and chelating agents for transition metal ions, novel 8‐cyclo‐1,5,3,7‐diazadiphosphocines (5–16) were successfully synthesized in good yields via [4 + 2] cycloaddition reaction between 8‐cyclo‐1,5,3,7‐diazadiphosphocines (4a‐c) with dienophiles (dimethyl acetylenedicarboxylate [DMAD], diethyl acetylenedicarboxylate [DEAD], diethyl diazene‐1,2‐dicarboxylate [DEDAD], and diisopropyl diazene‐1,2‐dicarboxylate [DIPDAD]). The core precursor scaffolds (4a‐c) were prepared via a one‐pot reaction between heteroaromatic amine analogs (1a‐c), paraformaldehyde and hypophosphorous acid in the presence of 6 M HCl. The biological activity of all synthesized 8‐cyclo‐1,5,3,7‐diazadiphosphocines (4a‐c, and 5–16) was evaluated against several cancer cell lines.

Recent Advances in Zinc Oxide Nanostructures with Antimicrobial Activities.

This article reviews the recent developments in the synthesis, antibacterial activity, and visible-light photocatalytic bacterial inactivation of nano-zinc oxide. Polycrystalline wurtzite ZnO nanostructures with a hexagonal lattice having different shapes can be synthesized by means of vapor-, liquid-, and solid-phase processing techniques. Among these, ZnO hierarchical nanostructures prepared from the liquid phase route are commonly used for antimicrobial activity. In particular, plant extract-mediated biosynthesis is a single step process for preparing nano-ZnO without using surfactants and toxic chemicals. The phytochemical molecules of natural plant extracts are attractive agents for reducing and stabilizing zinc ions of zinc salt precursors to form green ZnO nanostructures. The peel extracts of certain citrus fruits like grapefruits, lemons and oranges, acting as excellent chelating agents for zinc ions. Furthermore, phytochemicals of the plant extracts capped on ZnO nanomaterials are very effective for killing various bacterial strains, leading to low minimum inhibitory concentration (MIC) values. Bioactive phytocompounds from green ZnO also inhibit hemolysis of Staphylococcus aureus infected red blood cells and inflammatory activity of mammalian immune system. In general, three mechanisms have been adopted to explain bactericidal activity of ZnO nanomaterials, including direct contact killing, reactive oxygen species (ROS) production, and released zinc ion inactivation. These toxic effects lead to the destruction of bacterial membrane, denaturation of enzyme, inhibition of cellular respiration and deoxyribonucleic acid replication, causing leakage of the cytoplasmic content and eventual cell death. Meanwhile, antimicrobial activity of doped and modified ZnO nanomaterials under visible light can be attributed to photogeneration of ROS on their surfaces. Thus particular attention is paid to the design and synthesis of visible light-activated ZnO photocatalysts with antibacterial properties

On-demand degradable embolic microspheres for immediate restoration of blood flow during image-guided embolization procedures

Degradable embolic agents that provide transient arterial occlusion during embolization procedures have been of interest for many years. Ideally, embolic agents are visible with standard imaging modalities and offer on-demand degradability, permitting physicians to achieve desired arterial occlusion tailored to patient and procedure indication. Subsequent arterial recanalization potentially enhances the overall safety and efficacy of embolization procedures. Here, we report on-demand degradable and MRI-visible microspheres for embolotherapy. Embolic microspheres composed of calcium alginate and USPIO nanoclusters were synthesized with an air spray atomization and coagulation reservoir equipped with a vacuum suction. An optimized distance between spray nozzle and reservoir allowed uniform size and narrow size distribution of microspheres. The fabricated alginate embolic microspheres crosslinked with Ca2+ demonstrated highly responsive on-demand degradation properties in vitro and in vivo. Finally, the feasibility of using the microspheres for clinical embolization and recanalization procedures was evaluated with interventional radiologists in rabbits. Digital subtraction angiography (DSA) guided embolization of hepatic arteries with these embolic microspheres was successfully performed and the occlusion of artery was confirmed with DSA images and contrast enhanced MRI. T2 MRI visibility of the microspheres allowed to monitor the distribution of intra-arterial (IA) infused embolic microspheres. Subsequent on-demand image-guided recanalization procedures were also successfully performed with rapid degradation of microspheres upon intra-arterial infusion of an ion chelating agent. These instant degradable embolic microspheres will permit effective on-demand embolization/recanalization procedures offering great promise to overcome limitations of currently available permanent and biodegradable embolic agents.

Magnetic Multiwall Carbon Nanotube Decorated with Novel Functionalities: Synthesis and Application as Adsorbents for Lead Removal from Aqueous Medium

Water pollution is one of the major challenges facing modern society because of industrial development and urban growth. This study is directed towards assessing the use of multiwall carbon nanotube, after derivatization and magnetization, as a new and renewable absorbent, to remove toxic metal ions from waste streams. The adsorbents were prepared by, first oxidation of multiwall carbon nanotube, then derivatizing the oxidized product with hydroxyl amine, hydrazine and amino acid. The adsorbents were characterized by various techniques. The adsorption efficiency of the multiwall carbon nanotube adsorbents toward Pb(II) was investigated. The effect of adsorbent’s dose, temperature, pH, and time on the adsorption efficiency were studied and the adsorption parameters that gave the highest efficiency were determined. The derivatives have unique coordination sites that included amine, hydroxyl, and carboxyl groups, which are excellent chelating agents for metal ions. The thermodynamic and kinetic results analysis results indicated spontaneous adsorption of Pb(II) by the multiwall carbon nanotube adsorbents at room temperature. The adsorption process followed pseudo-second-order and Langmuir isotherm model. The adsorbents were regenerated using 0.1 N HCl.

Impact of additive application on the establishment of fast and stable aerobic granulation.

Aerobic granular sludge (AGS) is a microbial biofilm self-aggregation, which is effective for nutrient and pollutant removal, through the development of dense microbial layers bound together with extracellular polymeric substances (EPSs). However, long start-up times and granule disintegration are still challenges ahead. An array of external additives, including ion chelating agents, sludge-based enhancers, and magnetic influence have been tested to overcome these barriers. The application of such additives may promote enhanced EPS production, neutralization of charges on the bacterial surface, acts as a core-induced agent, or as a bridge to connect EPSs and cell surfaces. Although additives may improve the granule formation without reducing treatment efficiencies, there are still environmental concerns due to the fate and toxicity of discharged excess sludge. This mini-review identifies an array of external additives and their mechanisms to improve granulation properties, and proposes discussion about the technical and economic viability of these additives. KEY POINTS: • Additives reduce granulation time and repair granule disintegration. • Biopolymer-based additives fulfill technical and environmental requirements. • Sludge-based additives are cheap and in line with the resource recovery concept. • The need for environmental-friendly additives for aerobic granular sludge process. • External additives affect granular biomass size distribution.

Purification and characterization of fat body lipase from the greater wax moth, Galleria mellonella (Lepidoptera: Pyralidae)

BackgroundInsect lipid mobilization and transport are currently under research, especially lipases and lipophorin because of their roles in the production of energy and lipid transport at a flying activity. The present study has been conducted to purify intracellular fat body lipase for the first time, from the last larval instar of Galleria mellonella.ResultsPurification methods by combination of ammonium sulfate [(NH4)2SO4] precipitation and gel filtration using Sephadex G-100 demonstrated that the amount of protein and the specific activity of fat body lipase were 0.008633 ± 0.000551 mg/ml and 1.5754 ± 0.1042 μmol/min/mg protein, respectively, with a 98.9 fold purity and recovery of 50.81%. Hence, the sephadex G-100 step was more effective in the purification process. SDS-PAGE and zymogram revealed that fat body lipase showed two monomers with molecular weights of 178.8 and 62.6 kDa. Furthermore, biochemical characterization of fat body lipase was carried out through testing its activities against several factors, such as different temperatures, pH ranges, metal ions, and inhibitors ending by determination of their kinetic parameters with the use of p-nitrophenyl butyrate (PNPB) as a substrate. The highest activities of enzyme were determined at the temperature ranges of 35–37 °C and 37–40 °C and pH ranges of 7–9 and 7–10. The partially purified enzyme showed significant stimulation by Ca2+, K+, and Na+ metal ions indicating that fat body lipase is metalloproteinase. Lipase activity was strongly inhibited by some inhibitors; phenylmethylsulfonyl fluoride (PMSF), ethylene-diaminetetractic acid (EDTA), and ethylene glycoltetraacetic acid (EGTA) providing evidence of the presence of serine residue and activation of enzymes by metal ions. Kinetic parameters were 0.316 Umg− 1 Vmax and 301.95 mM Km.ConclusionConsidering the purification of fat body lipase from larvae and the usage of some inhibitors especially ion chelating agents, it is suggested to develop a successful control of Galleria mellonella in near future by using lipase inhibitors.

Identification, recombinant protein production, and functional analysis of a M60-like metallopeptidase, secreted by the liver fluke Opisthorchis viverrini

The carcinogenic liver fluke Opisthorchis viverrini (O. viverrini) is endemic in Thailand and neighboring countries including Laos PDR, Vietnam and Cambodia. Infections with O. viverrini lead to hepatobiliary abnormalities including bile duct cancer–cholangiocarcinoma (CCA). Despite decades of extensive studies, the underlying mechanisms of how this parasite survives in the bile duct and causes disease are still unclear. Therefore, this study aims to identify and characterize the most abundant protein secreted by the parasite. Proteomics and bioinformatics analysis revealed that the most abundant secretory protein is a metallopeptidase, named Ov-M60-like-1. This protein contains an N-terminal carbohydrate-binding domain and a C-terminal M60-like domain with a zinc metallopeptidase HEXXH motif. Further analysis by mass spectrometry revealed that Ov-M60-like-1 is N-glycosylated. Recombinant Ov-M60-like-1 (rOv-M60-like-1) expressed in Escherichia coli (E. coli) was able to digest bovine submaxillary mucin (BSM). The mucinase activity was inhibited by the ion chelating agent EDTA, confirming its metallopeptidase identity. The enzyme was active at temperatures ranging 25–37 °C in a broad pH range (pH 2–10). The identification of Ov-M60-like-1 mucinase as the major secretory protein of O. viverrini worms warrants further research into the role of this glycoprotein in the pathology induced by this carcinogenic worm.

Green Synthesis, Characterization, DPPH and Ferrous Ion-chelating (FIC) Activity of Tetrakis-Schiff’s Bases of Terephthalaldehyde

Background: The role of small molecules as antioxidants to prevent the oxidation of other molecules and inhibit them from radical formation is the area of much interest to cure disease especially cancer. Moreover, the antioxidants play important role as stabilizers to prevent oxidation of fuels and lubricants. </P><P> Methods: In the present study, fifteen tetrakis-Schiff’s bases derivatives (1-15) were synthesized and screened for their antioxidant activities. Compounds 1-15 were synthesized by continuous stirring of reaction mixture of 1,4-bis (hydrazonomethyl)benzene (1 mmol) with various substituted aromatic aldehydes (2 mmol) in distilled water using acetic acid as catalyst at room temperature for 2-10 min. </P><P> Results: Our present study showed that all compounds are better ferrous ion-chelating agents except compound 1,4-bis((E)-((E)-(3,4-dimethoxybenzylidene)hydrazono)methyl)benzene (6) (IC50 = 329.26 ± 4.75 µM) which has slightly low activity than the standard EDTA (IC50 = 318.40 ± 5.53 μM). In addition, DPPH radical scavenging activity of eleven compounds showed higher activity than the standard. However, remaining four compounds showed comparable radical scavenging activity to the standard DPPH (IC50 = 257.77 ± 4.60 µM). </P><P> Conclusion: The series of fifteen Schiff’s bases (1-15) were synthesized and evaluated as antioxidants. From both assays, it has been demonstrated that most of the tetrakis-Schiff’s bases have potential to serve as leads for the development of antioxidant agents for future research.

Enhancing tumor chemotherapy and overcoming drug resistance through autophagy-mediated intracellular dissolution of zinc oxide nanoparticles.

Autophagy may represent a common cellular response to nanomaterials. In the present study, it was demonstrated that zinc oxide nanoparticle (ZON)-elicited autophagy contributes to tumor cell killing by accelerating the intracellular dissolution of ZONs and reactive oxygen species (ROS) generation. In particular, ZONs could promote Atg5-regulated autophagy flux without the impairment of autophagosome-lysosome fusion, which is responsible for ZON-elicited cell death in cancer cells. On the other hand, a further study revealed that a significant free zinc ion release in lysosomal acid compartments and sequential ROS generation in cells treated with ZONs were also associated with tumor cytotoxicity. Intriguingly, the colocalization between FITC-labeled ZONs and autophagic vacuoles indicates that the intracellular fate of ZONs is associated with autophagy. Moreover, the chemical or genetic inhibition of autophagy significantly reduced the level of intracellular zinc ion release and ROS generation separately, demonstrating that ZON-induced autophagy contributed toward cancer cell death by accelerating zinc ion release and sequentially increasing intracellular ROS generation. The modulation of autophagy holds great promise for improving the efficacy of tumor chemotherapy. Herein, ZONs were verified to enhance chemotherapy in both normal and drug-resistant cancer cells via synergistic autophagy elicitation. Further, this elicitation resulted in tremendous zinc ion release and ROS generation, which accounted for enhancing the tumor chemotherapy and overcoming drug resistance. No obvious changes in the expression level of P-gp proteins or the amount of doxorubicin uptake induced by ZONs in MCF-7/ADR cells also indicated that the increased zinc ion release and ROS generation via synergistic autophagy induction were responsible for overcoming the drug resistance. Finally, in vivo experiments involving animal models of 4T1 tumor cells revealed that the antitumor therapeutic effect of a combinatory administration obviously outperformed those of ZONs or free doxorubicin treatment alone at the same dose, which could be attenuated by the autophagy inhibitor wortmannin or ion-chelating agent EDTA. Taken together, our results reveal the mechanism wherein the autophagy induction by ZONs potentiates cancer cell death and a novel biological application for ZONs in adjunct chemotherapy in which autophagy reinforces zinc ion release and ROS generation.

Low Field Magnetic Stimulation Ameliorates Schizophrenia-Like Behavior and Up-Regulates Neuregulin-1 Expression in a Mouse Model of Cuprizone-Induced Demyelination.

White matter and myelin sheath integrity are disrupted in schizophrenia, and non-invasive magnetic brain stimulation targeting these tracts is a promising new therapeutic approach. In particular, deep-brain reachable low field magnetic stimulation (DMS) could alleviate cognitive impairment and depressive-like behaviors in animal models. In this study, we sought to assess the effects of DMS on myelin sheath damage and schizophrenia-like behaviors in the cuprizone-induced demyelination mouse model. Mice were fed cuprizone (copper ion chelating agent, 0.2% w/w mixed with food) for 6 weeks to induce demyelination. During these 6 weeks, mice were stimulated with either sham, low-frequency (LFS, delta frequency) DMS or high-frequency (HFS, gamma Hz) DMS for 20 min each day. Behavioral tests were conducted 24 h after the final DMS session. The myelin sheath was examined by immunohistochemistry and the expression of neuregulin-1 (NRG1)/ErbB4 in the prefrontal cortex was measured with Western blotting. Six weeks of HFS significantly alleviated schizophrenia-like behaviors in cuprizone mice, including improved nesting, social interaction and sensorimotor gating, while LFS improved sensorimotor gating only. HFS and LFS both repaired the myelin sheath and increased the expression of neuregulin-1 and its receptor ErbB4, in the prefrontal cortex of demyelinated mice. Our findings show that DMS is a potential effective neuromodulation technique for the treatment of schizophrenia. One possible mechanism underlying these therapeutic effects could involve the up-regulation of NRG1/ErbB4 signaling in the prefrontal cortex.

Effect of ion chelating agent on self-healing performance of Cement-based materials

Ion chelating agent, a novel crystalline additive, is used to improve the self-healing performance of cement-based materials on freeze-thaw damage and surface crack for prolonging service life of the construction. The pore size distribution, internal structure and compressive strength of mortar with ion chelating agent before and after freeze-thaw as well as self-healing were investigated by nuclear magnetic resonance, scanning electron microscope and mechanical property test. The width of surface crack of the mortar during self-healing was measured. The results show that the microstructure and mechanical properties of mortars are improved by ion chelating agent. After 28 days of curing, harmful pores (larger than 0.1 μm) proportion of mortar with 0.5 wt% ion chelating agent of the cement (C2) declines by 42.3%, compressive strength increases by 26.8%, and much needle-like crystals exists in pores comparing with the control mortar (C0). After 100 freeze-thaw cycles, the compressive strength loss, mass loss and harmful pores proportion of C2 reduce by 38.0%, 29.2% and 28.7% relative to C0. After curing in water for 28 days, the compressive strength recovery ratio of C2 is 51.8%, and lots of needle-like crystals are formed in pores and micro-cracks. Energy dispersive spectrometer analysis indicates that the main components of these needle-like crystals are calcium carbonate, CSH and ettringite. Besides, the surface crack of 0.32 mm width for C2 is self-healed and X-ray diffraction analysis shows that the self-healed product in the crack is calcium carbonate.

Synthesis of fluorescent BSA templated silver nanomaterials and it’s application of detection of Zn2+ and Co2+

In this paper, BSA (bovine serum albumin) was used as stabilizer and protectant to synthesize high fluorescent silver nanoparticles (BSA-AgNPs) in ice bath. A method for the detection of metal ions was developed by using silver nanoparticles as fluorescent probes. The experimental results show that the BSA-AgNPs has unique selectivity for cobalt ions and zinc ions. When the cobalt ion exists in the system, the BSA-AgNPs is destroyed and the fluorescence quenching is caused, and the correlation coefficient is R = 0.970 35 when the concentration of cobalt ion is 100 μmol/L–600 μmol/L, and the correlation coefficient is R = 0.970 35. When the zinc ion exists in the system, the interaction of Zn2+ and BSA leads to the rise of the BSA-AgNPs fluorescein, and the Zn2+ concentration is in the 100 μmol/L–600 μmol/L. BSA-AgNPs shows a good linear relationship. The correlation coefficient is 0.985 90. EDTA can be used as a metal ion chelating agent. The rapid complexation of Co2+ with EDTA blocked the interaction between Co2+ and BSA, and the fluorescence of BSA-AgNPs could be restored. Based on this, the label free detection of zinc ions and cobalt ions was completed. Therefore, the prepared high fluorescence BSA-AgNPs sensor has a good application prospect in ion detection.