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The enhancement of the self-cleaning ability of photocatalytic membranes and their degradation efficiency over tetracycline (TC) still remains a challenge. In this study, an alternative silver vanadate quantum dots (AgVO

The cobalt oxide-vanadium oxide (Co3O4-V2O5) combined with reduced graphene oxide (rGO) having band gap of ∼ 3.3 eV appeared as a suitable photocatalyst for selective oxidation of 2-naphthol to BINOL. C2-symmetric BINOL was achieved with good yield using hydrogen peroxide as the oxidant under UV-light irradiation. The same catalyst was chirally modified with cinchonidine and a newly synthesized chiral Schiff base ligand having a sigma-hole center. The strong interaction of the chiral modifiers with the cobalt-vanadium oxide was truly evident from various spectroscopic studies and DFT calculations. The chirally modified mixed metal oxide transformed the oxidative C C coupling reaction with high enantioselectivity. High enantiomeric excess upto 92 % of R-BINOL was obtained in acetonitrile solvent and hydrogen peroxide as the oxidant. A significant achievement was the formation of S-BINOL in the case of the cinchonidine modified catalyst and R-BINOL with the Schiff base ligand anchored chiral catalyst. The UV-light induced catalytic reaction was found to involve hydroxyl radical as the active reactive species. The spin trapping ESR and fluorescence experiment provided relevant evidence for the formation of such species through photodecomposition of hydrogen peroxide on the catalyst surface. The chiral induction to the resultant product was found to induce through supramolecular interaction like O H…π, H…Br interaction. The presence of sigma hole center was believed to play significant role in naphtholate ion recognition during the catalytic cycle.

The abnormal levels of two biological molecules, dopamine (DA) and Uric acid (UA), in human body are symptoms of diseases such as Parkinson's disease and arrhythmia. A novel lanthanum vanadate and multi-walled carbon nanotubes (LaV-MWCNTs) composite modified glassy carbon electrode (GCE) was developed and utilized as an efficient electrochemical sensor for the simultaneous detection of DA and UA. LaV-MWCNTs composite was successfully fabricated by a facile ultrasonic self-assembly method and identified by means of a series of successive measurements including XPS, XRD, FT-IR and FE-SEM. The LaV-MWCNTs modified GCE shows the concentration linear ranges of DA and UA are 2-100 μΜ using DPV. The limits of detection (LODs; signal-to-noise ratio of 3, S/N = 3) of the LaV-MWCNTs modified GCE sensor for DA and UA were calculated to be 0.046 μM and 0.025 μM, respectively. The feasibility of using the LaV-MWCNTs modified GCE sensor to detect DA and UA in a typical biological fluid, fetal bovine serum, was also evaluated by the standard addition method.

Sporadic Alzheimer's disease (sAD) is the most common type of dementia and progressive neurodegenerative disease. To establish the sAD model, intracerebroventricular (ICV) streptozotocin (STZ) at a dose of 3 mg/kg was administered bilaterally in rats on a stereotaxic apparatus. Behavioral tests such as Morris water maze (MWM), novel object recognition (NOR) and open field test were performed to evaluate cognitive and locomotor functions. Two treatment doses (5 mg/kg and 10 mg/kg) of sodium orthovanadate (SOV) and rivastigmine (2 mg/kg) were given orally to ICV-STZ induced rats for 21 days. Cortical and hippocampal tissues were dissected. Estimation of oxidative stress, mitochondrial dysfunction as complex I, II, III, IV activity, cholinergic function as acetylcholinesterase activity, ELISA for phosphorylated tau protein and insulin degrading enzyme (IDE), neuroinflammation as NF-κB gene expression and insulin signaling functioning as Q-RT-PCR for IR, IRS-1, PI3K, AKT, GSK-3β gene expression were performed. Behavioral results with SOV and rivastigmine treatment revealed decreased escape latency and increased discrimination index in MWM and NOR respectively. Treatment results with SOV also demonstrated attenuation of oxidative imbalance, improved mitochondrial activity, and reversed IDE and tau pathology. SOV treatment upregulated gene expression of IR, IRS-1, PI3K, and AKT, and downregulated that of GSK-3β. SOV results were compared with standard drug rivastigmine. Conclusively, the memory enhancement by SOV was mediated through oxidative balance, mitochondrial enzyme complex activation, and improved insulin signaling regulation. However, the primary mechanism of SOV remained attenuation of tau pathology by the upregulation of IRS-1/PI3K/AKT/GSK-3β pathway and reversal of insulin resistance in terms of IDE. Hence, in sAD paradigm, SOV contributed to memory improvement evident with the findings of behavioral studies, which can further potentially have clinical significance in AD.

The degradation of pharmaceutical micropollutants is an intensifying environmental problem and synthesis of efficient photocatalysts for this purpose is one of the foremost challenges worldwide. Therefore, this study was conducted to develop novel plasmonic Ag/Ag2O/BiVO4 nanocomposite photocatalysts by simple precipitation and thermal decomposition methods, which could exhibit higher photocatalytic activity for mineralized pharmaceutical micropollutants. Among the different treatments, the best performance was observed for the Ag/Ag2O/BiVO4 nanocomposites (5 wt.%; 10 min's visible light irradiation) which exhibited 6.57 times higher photodegradation rate than the pure BiVO4. Further, the effects of different influencing factors on the photodegradation system of tetracycline hydrochloride (TC-HCl) were investigated and the feasibility for its practical application was explored through the specific light sources, water source and cycle experiments. The mechanistic study demonstrated that the photogenerated holes (h+), superoxide radicals (•O2-) and hydroxyl radicals (•OH) participated in TC-HCl removal process, which is different from the pure BiVO4 reaction system. Hence, the present work can provide a new approach for the formation of novel plasmonic photocatalysts with high photoactivity and can act as effective practical application for environmental remediation.

Dynamic tyrosine phosphorylation is fundamental to a myriad of cellular processes. However, the inherently low abundance of tyrosine phosphorylation in the proteome and the inefficient enrichment of phosphotyrosine(pTyr)-containing peptides has led to poor pTyr peptide identification and quantitation, critically hindering researchers' ability to elucidate signaling pathways regulated by tyrosine phosphorylation in systems where cellular material is limited. The most popular approaches to wide-scale characterization of the tyrosine phosphoproteome use pTyr enrichment with pan-specific, anti-pTyr antibodies from a large amount of starting material. Methods that decrease the amount of starting material and increase the characterization depth of the tyrosine phosphoproteome while maintaining quantitative accuracy and precision would enable the discovery of tyrosine phosphorylation networks in rarer cell populations. To achieve these goals, the BOOST (Broad-spectrum Optimization Of Selective Triggering) method leveraging the multiplexing capability of tandem mass tags (TMT) and the use of pervanadate (PV) boost channels (cells treated with the broad-spectrum tyrosine phosphatase inhibitor PV) selectively increased the relative abundance of pTyr-containing peptides. After PV boost channels facilitated selective fragmentation of pTyr-containing peptides, TMT reporter ions delivered accurate quantitation of each peptide for the experimental samples while the quantitation from PV boost channels was ignored. This method yielded up to 6.3-fold boost in pTyr quantification depth of statistically significant data derived from contrived ratios, compared with TMT without PV boost channels or intensity-based label-free (LF) quantitation while maintaining quantitative accuracy and precision, allowing quantitation of over 2300 unique pTyr peptides from only 1 mg of T cell receptor-stimulated Jurkat T cells. The BOOST strategy can potentially be applied in analyses of other post-translational modifications where treatments that broadly elevate the levels of those modifications across the proteome are available.

A series of five decavanadates (V

Dicalcium silicate (C2S) is known to incorporate potentially hazardous metals (Cr and V) in a belite-rich cementitious system. The effect of the electrovalence nature of V and Cr on C2S polymorphs’ (α´, β, γ) stability under oxidizing and reducing conditions as well as their reactivity are systematically investigated via analyzing oxidation states, phase composition, bonding system, and microstructure as well as oxide composition quantitively. It is shown that C2S can incorporate Cr (VI) and V(V) consequently leading to stabilization of α´, β-C2S. Instead, Cr (II, III) and V < (V) tend not to substitute in C2S. Despite reactive polymorphs (α´, β-C2S) stability due to Cr (VI) and V(V) incorporation, the early age (48-72 h) C2S reactivity is drastically reduced due to Cr (VI) and V (V) incorporation. Moreover, one batch leaching test revealed that the V (V) leaching is inversely proportional to aqueous Ca2+ ion at pH > 12 while Cr leaching is sensitive to its oxidation state, and dissolution of C2S. Even though C2S can incorporate Cr (VI) and V (V) ions, the final leaching is governed by the immobilization potential of C-S-H gel, pH as well as types of calcium chromate and vanadate complexes.

Vanadium (V) is a transitional metal that poses health risks to exposed humans. Microorganisms play an important role in remediating V contamination by reducing more toxic and mobile vanadate (V(V)) to less toxic and mobile V(IV). In this study, DNA-stable isotope probing (SIP) coupled with metagenomic-binning was used to identify microorganisms responsible for V(V) reduction and determine potential metabolic mechanisms in cultures inoculated with a V-contaminated river sediment. Anaeromyxobacter and Geobacter spp. were identified as putative V(V)-reducing bacteria, while Methanosarcina spp. were identified as putative V(V)-reducing archaea. The bacteria may use the two nitrate reductases NarG and NapA for respiratory V(V) reduction, as has been demonstrated previously for other species. It is proposed that Methanosarcina spp. may reduce V(V) via anaerobic methane oxidation pathways (AOM-V) rather than via respiratory V(V) reduction performed by their bacterial counterparts, as indicated by the presence of genes associated with anaerobic methane oxidation coupled with metal reduction in the metagenome assembled genome (MAG) of Methanosarcina. Briefly, methane may be oxidized through the "reverse methanogenesis" pathway to produce electrons, which may be further captured by V(V) to promote V(V) reduction. More specially, V(V) reduction by members of Methanosarcina may be driven by electron transport (CoMS-SCoB heterodisulfide reductase (HdrDE), F

The gadolinium vanadate nanostructure decorated functionalized carbon nanofiber (GdVO

In this report, we propose a fast, reliable and convenient approach to determine the alkaline phosphatase (ALP) activity based on a label-free fluorescence strategy. Upon catalysis of ALP, dephosphorylated dsDNA hampers the λ exonuclease (λexo) cleavage, shows high affinity to SYBR Green I (SG I), resulting in a strong fluorescence emission peak at 520 nm. In the absence of ALP, the dsDNA with 5′-phosphoryl-termini could be employed as a substrate of λexo. After cleavage, a weak fluorescence emission peaks at 520 nm could be observed. The assay was both selective and sensitive, and the detection limit was found to be as low as 3 U/L. This method was utilized to evaluate Na3VO4 as ALP inhibitor. The method was successfully applied to the determination of the activity of ALP in spiked human serum samples.

Modified Fe3O4 magnetic nanoparticles (magnetic nanocarrier) technology have found the proper place in separation and purification techniques, such as protein and enzyme purification, mostly due to its easy and fast operational procedure by using an external permanent magnet. Herein, Fe3O4 magnetic nanoparticles were prepared, and surface modification was performed with vanadate and phosphate salts to yield four various model of magnetic nanocarriers. Affinity ligands which are used for immobilization on the nanocarriers leading to the development of appropriative nanocarriers for the affinity separation of alkaline phosphatase from the bovine milk. The findings showed that the use of sodium hexametaphosphate affinity ligand attached to the carrier with an 18-atom linker leads to better separation of alkaline phosphatase from the bovine milk with 14.1-fold purification efficiency. All results confirmed that our designed nanocarriers can purify alkaline phosphatase using a fast and low-cost approach.

Polyoxidometalates (POMs) exhibit a range of biological properties that can be exploited for a variety of therapeutic applications. However, their potential utility as antivirals has been largely overlooked in the ongoing efforts to identify safe, effective and robust therapeutic agents to combat COVID-19. We focus on decavanadate (V10), a paradigmatic member of the POM family, to highlight the utility of electrostatic forces as a means of disrupting molecular processes underlying the SARS-CoV-2 entry into the host cell. While the departure from the traditional lock-and-key approach to the rational drug design relies on less-specific and longer-range interactions, it may enhance the robustness of therapeutic agents by making them less sensitive to the viral mutations. Native mass spectrometry (MS) not only demonstrates the ability of V10 to associate with the receptor-binding domain of the SARS-CoV-2 spike protein, but also provides evidence that this association disrupts the protein binding to its host cell-surface receptor. Furthermore, V10 is also shown to be capable of binding to the polybasic furin cleavage site within the spike protein, which is likely to decrease the effectiveness of the proteolytic processing of the latter (a pre-requisite for the viral fusion with the host cell membrane). Although in vitro studies carried out with SARS-CoV-2 infected cells identify V10 cytotoxicity as a major factor limiting its utility as an antiviral agent, the collected data provide a compelling stimulus for continuing the search for effective, robust and safe therapeutics targeting the novel coronavirus among members of the POM family.

Depression is a psychiatric disorder characterized by low-esteem, anhedonia, social deficit, and lack of interest. Decreased brain-derived neurotrophic factor (BDNF) and impaired tropomyosin kinase B receptor (TrkB receptor) signaling are associated with depression. In our study, depressive-like behavior was induced in mice by chronic unpredictable mild stress (CUMS) model. Various behavioral tests like tail suspension test (TST), open field test (OFT), sucrose preference test (SPT); biochemical analyses for corticosterone, reduced glutathione (GSH), lipid peroxidation (LPO), superoxide dismutase (SOD), nitric oxide (NO) and enzyme-linked immunosorbent assay (ELISA) for BDNF were performed. Body weight was measured every week. CUMS induced depressive-like behavior was found to be associated with increased oxidative stress in the brain and serum corticisterone with subsequent reduction of BDNF. Sodium orthovanadate (SOV), a protein tyrosine phosphatase inhibitor already reported to elevate BDNF levels, was used as the test drug. Sodium orthovanadate (5 mg/kg, 10 mg/kg) and fluoxetine (FLX-10 mg/kg) was given to mice orally for 21days before 30 min of stress induction. The behavioral tests reflected depressive-like behavior in CUMS, which was attenuated by both SOV and fluoxetine. SOV at 10 mg/kg demonstrated significant results in the present study characterized by decreased malondialdehyde levels (MDA/LPO), NO levels, and increased GSH level and SOD activity in both the cortex and hippocampus. Besides, ELISA has revealed the significant elevation of BDNF levels in the treatment groups (SOV-5 mg/kg, 10 mg/kg and FLX-10 mg/kg) as compared to the disease group (CUMS). Therefore, the treatment with SOV appeared to reverse both oxidative and nitrosative stress. Decreased serum corticosterone levels observed with SOV (510 mg/kg), FLX-10 mg/kg, FLX (10 mg/kg) + SOV (5 mg/kg); and SOV-10 mg/kg per-se treatment and elevated BDNF level with SOV (510 mg/kg), FLX-10 mg/kg were associated with attenuation of depressive-like behavior. The findings of this preliminary study indicate that SOV has the potential to restore antidepressant-like effects or prevent stress-induced anhedonia and so further molecular mechanisms are warranted for clinical translation.

The photocatalytic performance of a semiconducting catalytic system is strongly influenced by charge-carrier separation rate, charge transport properties, surface area, utilization of light energy, and interface bonding. Herein, a series of bismuth vanadate (BiVO4) samples were prepared via hydrothermal method by changing the volume ratios of ethelene glycol and ethanol as a solvent mixture for bismuth precursors. Further, the optimized BiVO4 sheets with hierarchical morphology were used to construct an interface with rod-like g-C3N4 materials, which was confirmed by HRSEM and HRTEM. Due to the formation of an effective interface bonding between BiVO4/g-C3N4, the photoinduced charge carrier's recombination rate was suppressed as confirmed by the PL analysis. The prepared BiVO4/g-C3N4 sample were used to assess the photodegradation efficiency of Rhodamine B (RhB) under direct sunlight irradiation and the photocatalysts degraded ~92.8% of RhB within 2 h. The TOC measurements revealed a 66.4% mineralization efficiency for RhB. In addition, the radical trapping experiments demonstrated that superoxide and hydroxyl radicals are the main reactive species for the degradation. Based on the experimental evidences, a plausible charge transfer mechanism has been proposed. The enhanced photocatalytic activity has been mainly attributed to the inhibition of the recombination rate, enhanced charge carrier transfer efficiency, and high rate of production of reactive species.

Previous studies have confirmed that protein tyrosine phosphatase 1B (PTP1B) can promote tumour progression in non-small cell lung cancer (NSCLC). Vanadyl alginate oligosaccharides (VAOS) is a new coordination compounds that possesses a good PTP1B inhibitory activity. However, the potent anticancer efficacy of VAOS in human NSCLC requires further study. In this study, VAOS exhibited effective inhibitory effects in NSCLC both in cultured cells and in a xenograft mouse model. VAOS was further identified to induce NSCLC cell apoptosis through activating protein kinase B (AKT) to elevate intracellular reactive oxygen species (ROS) levels by increasing in oxygen consumption and impairing the ROS-scavenging system. Neither silencing of PTP1B by siRNA nor transient overexpression of PTP1B had an effect on the AKT phosphorylation triggered by VAOS, indicating that PTP1B inhibition was not involved in VAOS-induced apoptosis. Through phosphorus colorimetric assay, we demonstrated that VAOS notably inhibited phosphatase and tensin homologue deleted on chromosome 10 (PTEN) dephosphorylation activity, another member of the protein tyrosine phosphatases (PTPases)-upstream factor of AKT. Interestingly, PTEN knockdown sensitized cells to VAOS, whereas ectopic expression of PTEN markedly rescued VAOS-mediated lethality. In vivo, VAOS treatment markedly reduced PTEN activity and tumour cell burden with low systemic toxicity. Thus, our data not only provided a new therapeutic drug candidate for NSCLC, but presented new understanding into the pharmacological research of VAOS.

A novel nitrogen doped carbon quantum dots (N-CQDs) mediated Ag3PO4/BiVO4 Z-scheme photocatalyst was synthesized through a solvothermal-precipitation method. The as-prepared photocatalysts were comprehensive characterized by X-ray diffraction, X-ray photo-electron spectroscopy, scanning electron microscopy, transmission electron micrograph, UV–vis diffuse reflection spectroscopy, vis photoluminescence and electron spin resonance analysis. The photocatalytic performances of as-prepared photocatalysts were used for degradation of tetracycline (TC) under visible-light illumination. Results exhibited the increased photocatalytic efficiency of BiVO4/N-CQDs/Ag3PO4-10 (Ag3PO4 with the mass ratio of BiVO4/N-CQDs/Ag3PO4 = 10%) to photodegrade TC is up to 88.9% in 30 min and 59.8% mineralization in 90 min. The degradation reaction coefficient (k) is about 6.00, 2.78 and 1.80 times higher than that of BiVO4, N-CQDs/BiVO4 and Ag3PO4/BiVO4, respectively. The excellent photocatalytic performance of the Z-scheme BiVO4/N-CQDs/Ag3PO4 was attributed to the construction of Z-scheme system, increased light harvesting capacity and improved molecular oxygen activation ability. Moreover, the photocatalytic activity of BiVO4/N-CQDs/Ag3PO4 remained 79.9% after five cycling runs, indicating the high stability and reusability of the as-prepared photocatalyst. Additionally, a possible photocatalytic mechanism of the novel Z-scheme BiVO4/N-CQDs/Ag3PO4 was proposed.

Creatine kinase, a key biomarker associated with many debilitating physiological conditions has seldom been detected in biological fluids using functionalized gold nanoparticles (GNPs). We have developed a method based on the aggregation of cysteamine (Cys) functionalized GNPs in presence of ATP for effective detection of creatine kinase (CK-MM). Positively charged Cys-GNPs (brick red color) aggregate in presence of negatively charged ATP (blue color) but the process is prevented when CK-MM is added to the solution. The analytical response to the concentration of CK-MM is linear (R2 = 0.9850). The proposed method is selective in sensing the CK-MM for a range of 5.617 × 103 ng/ml, 0.5617 ng/ml. The limit of detection was found to be 0.569 ng/ml in solution and 0.553 ng/ml in human serum with high selectivity.

Accumulation and polarization of anti-inflammatory M2 to proinflammatory M1 macrophage in the adipose tissue of obese diabetic mice is an important pathogenic signature. It worsens lipid induced inflammation and insulin resistance. Here we demonstrate that a small molecule, a peroxyvanadate compound i.e. DmpzH [VO(O2)2 (dmpz)] or dmp, could robustly decrease macrophage infiltration, accumulation and their polarization in high fat diet (HFD) induced obese diabetic mice. In searching the underlying mechanism it was revealed that SIRT1 level was strikingly low in the inflamed adipose tissue of HFD mice as compared to mice fed with standard diet (SD). Administration of dmp markedly increased SIRT1 level by inducing its gene expression with a consequent decrease in macrophage population. Elevation of SIRT1 coincided with the decrease of MCP1, Fetuin-A (FetA) and IFNγ. Since MCP1 and FetA drive macrophage to inflamed adipose tissue and IFNγ promotes M2 to M1 transformation, both recruitment and M1 induced inflammation were found to be significantly repressed by dmp. In addressing the question about how dmp induced excess SIRT1 could reduce MCP1, FetA and IFNγ levels, we found that it was due to the inactivation of NFκB because of its deacetylation by SIRT1. Since NFκB is the transcriptional regulator of these molecules, their expressions were significantly suppressed and that caused sharp decline in macrophage recruitment and their polarity to M1. This effected a marked fall in proinflammatory cytokine level which significantly improved insulin sensitivity. dmp is likely to be the first molecule that rescues inflammatory burden contributed by macrophage in obese diabetic mice adipose tissue which causes significant increase in insulin sensitivity therefore it may be a meaningful choice to treat type 2 diabetes.

MsbA, a homodimeric ABC exporter, translocates its native substrate lipid A as well as a range of smaller, amphiphilic substrates across the membrane. Magic angle sample spinning (MAS) NMR, in combination with dynamic nuclear polarization (DNP) for signal enhancement, has been used to probe two specific sites in transmembrane helices 4 and 6 of full length MsbA embedded in lipid bilayers. Significant chemical shift changes in both sites were observed in the vanadate-trapped state compared to apo state MsbA. The reduced spectral line width indicates a more confined conformational space upon trapping. In the presence of substrates Hoechst 33342 and daunorubicin, further chemical shift changes and line shape alterations mainly in TM6 in the vanadate trapped state were detected. These data illustrate the conformational response of MsbA towards the presence of drugs during the catalytic cycle. This article is part of a Special Issue entitled: Beyond the Structure-Function Horizon of Membrane Proteins edited by Ute Hellmich, Rupak Doshi and Benjamin McIlwain.

Dual oxygenases (DUOX) 1 and 2, expressed in many animal tissues, participate in host defense at mucosal surfaces and may have important signaling roles through generation of reactive oxygen. Present work addresses their expression in cultured human epidermal keratinocytes and effects of cytokines and metal/metalloid compounds. Both DUOX1 and 2 were expressed at much higher levels after confluence than in the preconfluent state. Maximal DUOX1 mRNA levels were 50 fold those of DUOX2. DUOX1 and 2 were induced ≈3 fold by interleukin 4, but only DUOX1 was induced by interferon gamma (IFNγ). In human bronchial HBE1 cells, by contrast, interleukin 4 induced only DUOX 1, and IFNγ induced only DUOX2. A survey in the keratinocytes of metal/metalloid compounds showed that arsenite, antimonite, chromate, cadmium, copper, lead and vanadate suppressed DUOX1 levels but did not prevent interleukin 4 stimulation. Effects on DUOX2 were less dramatic, except that vanadate potentiated the stimulation by IFNγ up to 7 fold. The results indicate that epithelial cell types of different tissue origins can differ in their cytokine regulation and that epidermal cells can exhibit striking alterations in response due to certain metal/metalloid exposures.

Objective To determine the distribution of higher psychological risk features within movement-based subgroups for people with low back pain (LBP). Design Cross-sectional observational study. Setting Participants were recruited from physiotherapy clinics and community advertisements. Measures were collected at a university outpatient-based physiotherapy clinic. Participants People (N=102) seeking treatment for LBP. Interventions Participants were subgrouped according to 3 classification schemes: Mechanical Diagnosis and Treatment (MDT), Treatment-Based Classification (TBC), and O'Sullivan Classification (OSC). Main Outcome Measures Questionnaires were used to categorize low-, medium-, and high-risk features based on depression, anxiety, and stress (Depression, Anxiety, and Stress Scale–21 Items); fear avoidance (Fear-Avoidance Beliefs Questionnaire); catastrophizing and coping (Pain-Related Self-Symptoms Scale); and self-efficacy (Pain Self-Efficacy Questionnaire). Psychological risk profiles were compared between movement-based subgroups within each scheme. Results Scores across all questionnaires revealed that most patients had low psychological risk profiles, but there were instances of higher (range, 1%–25%) risk profiles within questionnaire components. The small proportion of individuals with higher psychological risk scores were distributed between subgroups across TBC, MDT, and OSC schemes. Conclusions Movement-based subgrouping alone cannot inform on individuals with higher psychological risk features.

Indigenous microbial consortia are closely associated with soil inherent components including nutrients and minerals. Although indigenous microbial consortia present great prospects for bioremediation of vanadate [V(V)] contaminated soil, influences of some key components, such as available phosphorus (AP), on V(V) biodetoxification are poorly understood. In this study, surface soils sampled from five representative vanadium smelter sites were employed as inocula without pretreatment. V(V) removal efficiency ranged from 81.7 ± 1.4% to 99.5 ± 0.2% in batch experiment, and the maximum V(V) removal rates were positively correlated with AP contents. Long-term V(V) removal was achieved under fluctuant hydrodynamic and hydrochemical conditions in column experiment. Geobacter and Bacillus, which were found in both original soils and bioreactors, catalytically reduced V(V) to insoluble tetravalent vanadium. Phosphate-solubilizing bacterium affiliated to Gemmatimonadaceae were also identified abundantly. Microbial functional characterization indicated the enrichment of phosphate ABC transporter, which could accelerate V(V) transfer into intercellular space for efficient reduction due to the structural similarity of V(V) and phosphate. This study reveals the critical role of AP in microbial V(V) decontamination and provides promising strategy for in situ bioremediation of V(V) polluted soil.

Conventional photothermal therapy (PTT) is insufficient to induce a strong and potent anti-tumor immune response. Herein, we present a vanadyl nanocomplex, which simultaneously serves as a photothermal agent (PTA) and an immunogenic cell death (ICD) inducer to enhance the anti-tumor immunity of PTT. The vanadyl nanocomplex (STVN) is constructed via facile one-step coordination assembly under ambient conditions. STVN not only has a strong and stable photothermal effect under near-infrared (NIR) irradiation, but also can cause severe endoplasmic reticulum (ER) stress by itself, leading to ICD and activating the systemic immune responses. In the absence of any adjuvants, NIR-irradiated STVN almost completely ablates primary tumors and simultaneously inhibits distant tumors in mice bearing bilateral melanoma. Meanwhile, the intratumorally injected STVN combined with NIR effectively suppressed melanoma lung metastasis as well as tumor recurrence, displaying that local STVN-mediated PTT could trigger a systemic anti-tumor immunity. Therefore, STVN, as a novel immunogenicity-enhanced PTA, affords a "one stone two birds" strategy for improved photothermia-induced cancer immunotherapy.

The monitoring of oxyanions in waters, presents significant challenges due to their relatively low concentrations, and a characteristically changeable/unstable/reactive geochemistry with high spatial and temporal turnover. This results in a very heterogeneous pattern of mobility and bioavailability, which is difficult to capture reliably and in a cost effective manner. The diffusive gradients in thin-films (DGT) technique is a popular analytical tool for testing water quality, primarily because it provides a time-integrated measurement. However, to date, the most widely used DGT configuration for oxyanion sampling, the slurry ferrihydrite binding layer (SF-DGT) has only been fully characterized for phosphate. Confirmatory testing of the functional range of ionic strengths, pH, deployment times and ionic competition effects, that the SF-DGT's operates within has not been carried out, but is addressed in this study for VV, AsV, SbV, and MoVI. In this study SF-DGT SbV measurements functioned over the largest range of conditions (ionic strength, 0.1–500 mM; pH 3.86–9.90), while ionic strengths above 100 and 500 mM were found to be problematic for AsV and MoVI, respectively. Low pH (below 4) caused inferences with VV, conversely AsV and MoVI determination faltered/deviated from predicted responses in pH conditions of ∼9. SF-DGT measurements adequately predicted up to weeklong averaged in situ metal oxyanion concentrations in a freshwater river. This study concludes that the SF-DGT configuration is highly suitable for pollution monitoring applications in freshwater systems for key oxyanion species.

Polysaccharides and vanadium compounds have been studied due to their antitumor potential. In this study, the cytotoxic effects of galactomannan preparations on HepG2 cells were investigated. Native galactomannan from S. amazonicum (SAGM) and its modified form (MSAGM) were complexed with oxovanadium resulting in SAGM:VO and MSAGM:VO, respectively. The complexation was confirmed by NMR, FTIR, and AAS. SAGM and MSAGM:VO (250μg/mL) after 72h decreased viability by 51% and 58%, respectively, while the inhibition of the HepG2 cell proliferation was of ∼27% and ∼46%, respectively. SAGM and MSAGM:VO (250μg/mL) significantly inhibited all states of respiration (basal: 85% and 63%; uncoupled: 90% and 70%; and leak: 30% and 58%) after 72h. ROS levels increased by ∼149% after the treatment with MSAGM:VO (250μg/mL) for 72h, while ΔΨm decreased by ∼50%. Our results indicate that galactomannan preparations from S. amazonicum, especially SAGM and the MSAGM:VO complex, could be considered as potential antitumor drugs for further investigations, once they have the ability to make HepG2 cells susceptible to death by affecting vital cellular processes such as respiration and ROS generation.

In Latin America Chagas disease is an endemic illness caused by the parasite Trypanosoma cruzi (T. cruzi), killing more people than any other parasitic disease. Current chemotherapies are old and inadequate, thus the development of efficient ones is urgently needed. Vanadium-based complexes have been shown to be a promising approach both against parasitic diseases and cancer and this study aims to achieve significant advances in the pursue of effective compounds. Heteroleptic vanadium complexes of Schiff bases and polypyridine compounds were prepared and their stability in solution evaluated by EPR (Electronic Paramagnetic Resonance) and NMR spectroscopy. Their in vitro activities were evaluated against T. cruzi and a set of cells lines representative of human cancer conditions, namely ovarian, breast and prostate cancer. In T. cruzi, most of the complexes depicted IC50 values in the low μM range, induced changes of mitochondrial membrane potential and apoptosis. In cancer cells, complexes showed good to moderate activity and in metastatic cells (prostate PC3), some complexes inhibited the migratory ability, this suggesting that they display antimetastatic potential. Interestingly, complex 5 seemed to have a dual effect being the most cytotoxic complex on all cancer cells and also the most active anti-T-cruzi compound of the series. Globally the complexes showed promising anticancer and anti T. cruzi activities and also displayed some characteristics indicating they are worth to be further explored as antimetastatic drugs.

T cell receptor (TCR) recognition of a peptide antigen in the context of MHC molecules initiates positive and negative cascades that regulate T cell activation, proliferation and differentiation, and culminate in the acquisition of effector T cell functions. These processes are a prerequisite for the induction of specific T cell-mediated adaptive immune responses. A key event in the activation of TCR-coupled signaling pathways is the phosphorylation of tyrosine residues within the cytoplasmic tails of the CD3 subunits, predominantly CD3ζ. These transiently formed phosphotyrosyl epitopes serve as docking sites for SH2-domain containing effector molecules, predominantly the ZAP70 protein tyrosine kinase, which is critical for signal propagation. We found that CrkI and CrkII adaptor proteins also interact with CD3ζ in TCR activated-, but not in resting-, T cells. Crk binding to CD3ζ was independent of ZAP70 and also occurred in ZAP70-deficient T cells. Binding was mediated by Crk-SH2 domain interaction with phosphotyrosine-containing motifs on CD3ζ, via a direct physical interaction, as demonstrated by Far-Western blot. CrkII binding to CD3ζ could also be demonstrated in a heterologous system, where coexpression of a catalytically active Lck was used to phosphorylate the CD3ζ chain. TCR activation-induced Crk binding to CD3ζ resulted in increased and prolonged phosphorylation of CD3ζ, as well as ZAP70 and LAT, suggesting a positive role for CrkI/II binding to CD3ζ in regulation of TCR-coupled signaling pathways. Furthermore, Crk-dependent increased phosphorylation of CD3ζ coincided with inhibition of TCR downmodulation, supporting a positive role for Crk adaptor proteins in TCR-mediated signal amplification.

In this present investigation, we introduced a novel electrochemical sensor for the detection of tryptophan (TRP) based on green pompoms flower-like cerium vanadate (CeVO4). The flower-like CeVO4 microstructure was prepared by the simple hydrothermal treatment with the assistance of urea for the first time. The as-prepared flower-like CeVO4 microstructure was characterized by various analytical and spectroscopic techniques such as X-ray diffraction, Raman spectroscopy fourier transform infrared spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy studies. The electrochemical properties are evaluated by the cyclic voltammetry (CV) and differential pulse voltammetry (DPV). As an electrochemical sensor, the green pompoms flower-like CeVO4 modified glassy carbon electrode (GCE) displayed an excellent electrocatalytic activity for the detection of TRP. The obtained electrochemical results revealed that the oxidation of TRP, exhibited a lower potential and higher anodic peak current when compared to unmodified GCE. These results were suggested that the flower-like CeVO4/GCE have a good electrocatalytic activity towards the TRP oxidation. The flower-like CeVO4 sensor exhibited the wide linear concentration range and low detection limit of 0.1-94µM and 0.024µM respectively. Finally, the proposed sensor was successfully applied to the determination of TRP in real sample analysis such as food and biological samples with satisfied recoveries.

A number of oxidovanadium(IV) complexes have been reported to display anticancer activity. A theranostic approach, based on the simultaneous observation of both the effect of oxidovanadium(IV) complexes on cell viability and the disclosure of their intracellular fate, is possible by using oxidovanadium(IV) complexes functionalized with fluorescent ligands. In the present study we accomplished the characterization of six oxidovanadium(IV) complexes in conditions close to those employed for in vitro administration. In particular, we investigated the light harvesting properties of such complexes in the presence of a dimethylsulphoxide/aqueous buffer mixture, and we found that one complex exhibits a quantum yield suitable for confocal microscopy investigations. EPR investigations in the same conditions provide information about the presence of ligands' substitution processes. Finally, the electrochemical properties of all complexes were determined by cyclic voltammetry. The overall results show that these complexes exhibit an average stability in solution; EPR data confirm that DMSO enter the first coordination sphere of oxidovanadium(IV) and suggest the occurrence of partial ligand substitution in the dimethylsulphoxide/aqueous buffer mixture.

The toxicity of vanadium in soils depends on its sorption to soil components. Here we studied the vanadate(V) sorption properties of 26 mineral soils. The data were used to optimise parameters for a Freundlich equation with a pH term. Vanadium K-edge XANES spectroscopy for three selected soils confirmed that the added vanadate(V) had accumulated mostly as adsorbed vanadate(V) on Fe and Al hydrous oxides, with only minor contributions from organically complexed vanadium(IV). Data on pH-dependent V solubility for seven soils showed that on average 0.36 H+ accompanied each V during adsorption and desorption. The resulting model provided reasonable fits to the V sorption data, with r2 > 0.99 for 20 of 26 soils. The observed KdS value, i.e. the ratio of total to dissolved V, was strongly dependent on V addition and soil; it varied between 3 and 4 orders of magnitude. The model was used to calculate the Freundlich sorption strength (FSS), i.e. the amount of V sorbed at [V] = 2.5 mg L−1, in the concentration range of observed plant toxicities. A close relationship between FSS and oxalate-extractable Fe and Al was found (r2 = 0.85) when one acidic soil was removed from the regression. The FSS varied between 27 and 8718 mg V kg−1, showing that the current environmental guidelines can be both under- and overprotective for vanadium. QC 20170609

Two mixed-valence octadecavanadates, (NH 4) 2(Me 4N) 5[V IV 12V V 6O 42I]·Me 4NI·5H 2O (V 18I) and [{K 6(OH 2) 12V IV 11V V 7O 41(PO 4)·4H 2O} n] (V 18P), were synthesized and characterized by single-crystal X-ray diffraction analysis and FTIR, Raman, 51V NMR, EPR and UV/Vis/NIR spectroscopies. The chemoprotective activity of V 18I and V 18P towards the alkylating agent diethyl sulfate was assessed in E. coli cultures. The complex V 18I was nontoxic in concentrations up to 5.0 mmol L −1, while V 18P presented moderate toxicity in the concentration range 0.10 - 10 mmol L −1. Conversely, a ca. 35% enhancement in culture growth as compared to cells treated only with diethyl sulfate was observed upon addition of V 18I (0.10 to 2.5 mmol L −1), while the combination of diethyl sulfate with V 18P increased the cytotoxicity presented by diethyl sulfate alone. 51V NMR and EPR speciation studies showed that V 18I is stable in solution, while V 18P suffers partial breakage to give low nuclearity oxidometalates of vanadium(V) and (IV). According to the results, the chemoprotective effect depends strongly on the direct reactivity of the polyoxidovanadates (POV) towards the alkylating agent. The reaction of diethyl sulfate with V 18I apparently produces a new, rearranged POV instead of poorly-reactive breakage products, while V 18P shows the formation and subsequent consumption of low-nuclearity species. The correlation of this chemistry with that of other mixed-valence polyoxidovanadates, [H 6V IV 2V V 12O 38PO 4] 5- (V 14) and [V IV 8V V 7O 36Cl] 6- (V 15), suggests a relationship between stability in solution and chemoprotective performance.

In this work, we designed tetragonal nanogravel structured dysprosium vanadate Dy(VO4) nanoparticles unified with oxidized carbon nanofiber (f-CNF) denoted as Dy(VO4)/f-CNF nanocomposite for the low potential determination of antiprotozoal drug metronidazole (MEZ). The physicochemical properties of novel Dy(VO4)/f-CNF nanocomposite were analyzed through microscopic and spectroscopic techniques and obtained results express nanocomposite formed with desired surface morphology, crystalline phase, atomic vibrational modes, and preferred elemental compositions. The electrocatalytic activity of Dy(VO4)/f-CNF nanocomposite was examined with a disposable screen-printed electrode (SPCE) via cyclic voltammetry (CV) and linear sweep voltammetry technique (LSV) with a conventional three-electrode system. Dy(VO4)/f-CNF/SPCE delivers a higher active surface area recommends superior electrocatalytic activity which is favorable for the MEZ sensor. Electrocatalytic reduction of MEZ occurred with lower reduction potential (−0.55 V) with dynamic linear range (1.5–1036.9 µM), lower detection limit (6 nm), LOQ (0.022 µM), and higher sensitivity (1.12 μA μM−1 cm2). The anti-interference studies retain its actual current without any shift in cathodic potential. Besides, the practical feasibility outcomes with higher cathodic current with the higher recovery rate and RSD in human blood sample, urine sample, and lake water as a real samples. Thus, Dy(VO4)/f-CNF nanocomposite modified SPCE considers being a potential candidate for the MEZ sensor.

Background Non-small-cell lung cancer (NSCLC) is the most frequent type of lung cancer and more than 90 % of mortality is due to metastasis-related deaths. Flavonoids are considered nutraceuticals due to the variety of pharmacological properties. In this paper, we studied the effects of baicalin, silibinin, apigenin, luteolin, and its oxidovanadium(IV) cation complexes on the viability, adhesion to fibronectin, invasion, and migration on human lung cancer cell line A549. In addition, in order to complete the study of the interaction of VOflavonoids and bovine serum albumin (BSA), the binding ability of silibinin and VOsil to the protein was evaluated. Method To establish the non-cytotoxic concentration range of the tested compounds, the cancer cell viability was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Cell migration and invasion assays were performed using Boyden chambers and adhesion assay using MTT method. The interaction of compounds with BSA were investigated in physiological buffer (pH = 7.4) by fluorescence spectroscopy. Results All complexes inhibited the metastatic cascade steps to a greater extent than their respective ligands. Likewise, based on binding constant values (Kb) for BSA-silibinin and BSA-VOsil, we can suggest that both compounds can interact with the protein. Conclusion Although all the complexes suppressed cell adhesion, invasion and migration, VOlut can be considered as a good candidate to continue the trials because it presented encouraging results as a potential antitumor and antimetastatic agent, and can be transported by BSA.

Mackinawite (FeS), a widely-distributed natural reducing mineral, can donate electron for various (bio)processes. However, little is known about mackinawite-driven chemoautotrophic bioreduction of toxic vanadate [V(V)] in aquifer. This study demonstrates that V(V) is successfully bioreduced by mackinawite under anaerobic condition via 150-d operation of constructed aquifer. Complete V(V) removal was achieved at the initial concentration of 10 mg/L and flow rate of 0.125 mL/min. Fluctuant hydrochemistry and hydrodynamics affected V(V) removal performance. Biotic activity was identified as the major contribution to V(V) transformation (76.4 ± 1.01%). Chemoautotrophic genera (e.g., Thiobacillus) could oxidize FeS coupled to direct V(V) reduction independently. Heterotrophic V(V) reducers (e.g., Pseudomonas and Spirochaeta) could also achieve V(V) detoxification by utilizing metabolic intermediates synthesized by autotrophic Fe(II) oxidizers (e.g., Thiobacillus) and S(-II) oxidizing genera (e.g., Sulfuricurvum). Gene abundance and enzymatic activity tests confirmed that nitrate reductase gene napA functioned crucially in chemoautotrophic V(V) reduction by Fe(II) and S(-II) donating electron. V(V) was reduced to insoluble V(IV) while elements in mackinawite were oxidized to Fe(III) and SO42−. This study reveals the coupling of iron, sulfur and vanadium in biogeochemical cycling, and offers a promising strategy for remediation of V(V)-polluted aquifer.

51 V NMR spectroscopy was used for detection and identification of cell-associated vanadate (V 5+ ) species after exposure of Phycomyces blakesleeanus mycelium, in exponential phase of growth, to sodium orthovanadate. Complete disappearance of monomer and dimer signals and decreased intensity of the tetramer signal were observed about 40 min after treatment. Simultaneously, a signal at −532 ppm, with increasing intensity, was detected in spectra. The time-dependent rise in this signal was connected to a decrease in the extracellular monomer signal, indicating its transport into the cell. The signal at −532 ppm did not belong to any known simple oxido-vanadate species, nor to a complex with any of the components of experimental medium. This signal was the only one present in spectrum of the mycelium washed 35 min after treatment, and the only one observed in mycelium cultivated on vanadate-contained medium. Therefore, its appearance can be attributed to intracellular complexation, and may represent an important detoxification mechanism of the cell exposed to a physiologically relevant concentration of vanadate. Experiments ( 51 V NMR and polarography) performed with Cd-pretreated mycelium (inhibitor of an enzyme responsible for V 5+ reduction) and ferricyanide-preincubated mycelium excluded the possibility of V 5+ tetramer's entry into the cell.

The yeast Ste20 (sterile) protein kinase, which is a serine/threonine kinase, responds to the stimulation of the G proteincoupled receptor (GPCR) pheromone receptor. Ste20 protein kinase serves as the critical component that links signaling from the GPCR/G proteins to the mitogen-activated protein kinase (MAPK) cascade in yeast. The yeast Ste20p functions as a MAP kinase kinase kinase kinase (MAP4K) in the pheromone response. Ste20-like kinases are structurally conserved from yeast to mammals. The mechanism by which MAP4K links GPCR to the MAPK pathway is less clearly defined in vertebrates. In addition to MAP4K, the tyrosine kinase cascade bridges G proteins and the MAPK pathway in vertebrate cells. Mammalian Ste20 Kinase 3 (MST3) has been categorized into the Ste20 family and has been reported to function in the regulation of cell polarity and migration. However, whether MST3 tyrosine phosphorylation regulates diverse signaling pathways is unknown. In this study, the tyrosine phosphatase inhibitor pervanadate was found to induce MST3 tyrosine phosphorylation in intact cells, and the activity of tyrosine-phosphorylated MST3 was measured. This tyrosine-directed phosphorylation was independent of MST3 activity. Parameters including protein conformation, Triton concentration and ionic concentration influenced the sensitivity of MST3 activity. Taken together, our data suggests that the serine/threonine kinase MST3 undergoes tyrosinedirected phosphorylation. The tyrosine-phosphorylated MST3 may create a docking site for the structurally conserved SH2/SH3 (Src Homology 2 and 3) domains within the Src oncoprotein. The unusual tyrosinephosphorylated MST3 may recruit MST3 to various signaling components.

The purpose of this study was evaluate, for the first time, the impact of incorporation of nanostructured silver vanadate (β-AgVO3) in antibiofilm and mechanical properties of dental acrylic resins (poly(methyl methacrylate), PMMA).The β-AgVO3 was synthesized and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and microanalysis (SEM/EDS). Resins specimens were prepared with 0-10% wt.% β-AgVO3 and characterized by SEM, XRD and optical microscopy. The antibiofim activity of the samples against Candida albicans and Streptococcus mutans was investigated by XTT reduction test, colony-forming units (CFUs), and confocal laser scanning microscopy (CLSM). The flexural strength, hardness, and surface roughness of the samples containing β-AgVO3 were compared with the pure PMMA matrix.The incorporation of 10% β-AgVO3 significantly reduced the metabolic activity of C. albicans and S. mutans (p0.05). There was a reduction in microbial load (CFU/mL) of microorganisms for the different concentrations used (p0.05), which was confirmed by confocal microscopy. The addition of β-AgVO3 did not change the mechanical properties of hardness and surface roughness of the resins (p0.05). However, flexural strength decreased with the addition of amounts greater than 1% (p0.05).β-AgVO3 additions in dental acrylic resin may have an impact on inhibition of biofilm of main microorganisms associated with dental prostheses. However, the viability of clinical use should be evaluated in function of changed promoted in some mechanical properties.

Characterized as by X-ray diffraction, scanning electron microscopy and UV-vis diffuse reflectance spectra techniques, BiVO4 photocatalyst was hydrothermally synthesized. The photocatalytic degradation mechanisms of ibuprofen (IBP) were evaluated in aqueous media via BiVO4. Results demonstrated that the prepared photocatalyst corresponded to phase-pure monoclinic scheelite BiVO4. The synthesized BiVO4 showed superior photocatalytic properties under the irradiation of visible-light. The photocatalytic degradation rate of IBP decreased with an increase in the initial IBP concentration. The degradation process followed first-order kinetics model. At an IBP concentration of 10 mg L(-1), while a BiVO4 concentration of 5.0 g L(-1) with pH value of 4.5, the rate of IBP degradation was obtained as 90% after 25 min. The photocatalytic degradation of IBP was primarily accomplished via the generation of superoxide radical (O2(•-)) and hydroxyl radicals ((•)OH). During the process of degradation, part of the (•)OH was converted from the O2(•-). The direct oxidation of holes (h(+)) made a minimal contribution to the degradation of IBP.

Lanthanide-doped GdVO4 nanorods that exhibit upconversion emission under 982 nm excitation have been prepared by a facile room-temperature chemical co-precipitation method followed by a subsequent annealing at temperatures of 600 degrees C, 800 degrees C and 1000 degrees C. Multicolor upconversion emission, including white, was achieved by tuning the concentrations of dopant lanthanide ions (Ho3+, Er3+, Tm3+ and Yb3+) in GdVO4. It is found that four GdVO4 samples emit light with the white chromaticity coordinates of (0.326, 0.339), (0.346, 0.343), (0.323, 0327) and (0.342, 0.340) respectively, under a single-wavelength NIR excitation. These coordinates are very close to the standard equal energy white light coordinates (0333, 0.333) according to the 1931 CIE diagram. By varying dopant lanthanide concentrations in nanorods it is possible to produce upconversion emission with colors between red (0.504, 0369), green (0.282, 0.577) and blue (0.142, 0.125) coordinates. (C) 2015 Elsevier Ltd. All rights reserved.

We studied the hepatic and renal impact of sodium metavanadate (SMV) exposure in African giant rats (AGR). Twelve male AGR were used and divided into two groups. The control group received sterile water while the SMV-exposed group received 3 mg/kg SMV intraperitoneally for 14 days. SMV exposed AGR groups showed significantly decreased activities of serum AST, ALT, ALP and creatinine concentration but increased blood urea nitrogen (BUN), albumin and globulin concentrations. Kidney ultrastructure examination revealed atrophy of the glomerular tuft, loss of podocytes, distortions of the endothelium and glomerular basement membrane. The liver sinusoids fenestration phenotypes were abnormal. Hepatocytes exhibited hypertrophy with uneven, crenated and dentate nuclei. SMV exposure induced activation of monocytes, as well as Kupffer and fibrous cells. Alterations in glomerular podocytes and cell-cell and cell matrix contact and inflammatory liver fibrosis are key events in progressive glomerular failure and hepatic damage due to SMV intoxication.

Neuronal apoptosis caused by amyloid-beta (Aβ) overproduction is one of the most important pathological features in Alzheimer's disease (AD). Endoplasmic reticulum (ER) stress induced by Aβ overload plays a critical role in this process. Bis(ethylmaltolato)oxidovanadium (IV) (BEOV), a vanadium compound which had been regarded as peroxisome proliferator-activated receptor γ (PPARγ) agonist, was reported to exert an antagonistic effect on ER stress. In this study, we tested whether BEOV could ameliorate the Aβ-induced neuronal apoptosis by inhibiting ER stress. It was observed that BEOV treatment ameliorated both tunicamycin-induced and/or Aβ-induced ER stress and neurotoxicity in a dose-dependent manner through downgrading ER stress-associated and apoptosis-associated proteins in primary hippocampal neurons. Consistent with in vitro results, BEOV also reduced ER stress and inhibited neuronal apoptosis in hippocampi and cortexes of transgenic AD model mice. Moreover, by adopting GW9662 and salubrinal, the inhibitor of PPARγ and hyperphosphorylated eukaryotic translation initiation factor 2α, respectively, we further confirmed that BEOV alleviated Aβ-induced ER stress and neuronal apoptosis in primary hippocampal neurons by activating PPARγ. Taken together, these results provided scientific evidences to support the concept that BEOV ameliorates Aβ-induced ER stress and neuronal apoptosis through activating PPARγ.

Over the last decade, copper and vanadium complexes have shown promising properties for the treatment of several types of cancer. In particular, Casiopeinas®, a group of copper-based complexes, has received specific attention, and their mechanism of action has been extensively studied since their structure is simple and their synthesis may be affordable. Similarly, vanadium-containing compounds in the form of complexes and simple polyoxovanadates have also been studied as antitumor agents. Here, potential prodrugs that would release the two metals, V and Cu, in usable form to act in conjunction against cancer cells are reported. The new series of Casiopeinas-like compounds are bridged by a cyclotetravanadate ion with the generic formula [Cu(N,N')(AA)]2•(V4O12), where (N,N') represent 1,10-phenanthroline and 2,2'-bipyridine, and (AA) are aminoacidate ions (Lysine and Ornithine). The compounds were characterized by elemental analysis, single-crystal X-ray diffraction and Visible, FTIR, and Raman spectroscopies, as well as 51V NMR, EPR, and Thermogravimetric Analysis. Additionally, theoretical calculations based on the Density Functional Theory (DFT) were carried out to model the compounds. Optimized structures, theoretical IR, and Raman spectra were also obtained, as well as docking analysis to test DNA interactions with the casiopeina-like complexes. The compounds may act as prodrugs by providing acting molecules that have showed potential pharmacological properties for the treatment of several types of cancer.

Lutetium vanadate (LuVO4) is a promising material for electrochemical application owing to its good conductivity and electrocatalytic activity. Herein, we demonstrate a facile technique for the synthesis of a LuVO4/ graphene sheet (GRS) nanocomposite where LuVO4 is encapsulated with an ultrathin GRS to form a hierarchical structure (LuVO4/GRS). The resulting hierarchical LuVO4/GRS architecture was characterized by several analytical and spectroscopic techniques. The resultant electrocatalyst shows superior electrochemical sensing for nitrofurantoin (NFT) with a low detection limit (0.001 μM), wide linear range (0.008–256.0 μM) and excellent sensitivity (1.709 μA μM−1 cm-2). It has been demonstrated that the enhanced electrocatalytic performance of LuVO4/GRS nanocomposite is due to their excellent electrical conductivity, suitable surface area, high redox reaction and large number of electron transport. In addition, the LuVO4/GRS nanocomposite exhibited excellent response towards NFT detection with adequate reproducibility, good repeatability, long-term stability and excellent selectivity over its structural analogs and common interferents. Furthermore, the practical applicability of the proposed electrochemical sensor was successfully applied for determination of NFT in environmental samples with satisfactory results. The LuVO4/GRS nanocomposite presented here can serve as a favorable candidate for developing electrochemical sensor and plays an important role in widespread fields.

Alkaline phosphatase (ALP) is an important biomarker for diagnosis, and the abnormal level of serum ALP is closely related to a variety of diseases. In present work, a ratiometric fluorescence probe based on hybrid nanoparticles CDs@YVO4: Dy3+ nanoparticle is introduced for alkaline phosphatase (ALP) activity determination. The CDs@YVO4: Dy3+ probe is constructed by the carbon dots (CDs) and YVO4: Dy3+ through a simple mixing method, in which the blue emission of CDs at 405 nm acts as the calibrated signal, the green emission of YVO4: Dy3+ at 574 nm decreased with the increasing targets ALP, and used as the output signal. In addition, the Cu2+ and pyrophosphate (PPi) were also employed in this strategy to utilize the excellent fluorescnece quenching efficiency of Cu2+ to the Dy3+ ions emission of CDs@YVO4: Dy3+, as well as the strong affinity of PPi for Cu2+. In the presence of analyts ALP, ALP catalyzes the hydrolysis of PPi, causing the release of Cu2+, resulting in the Dy3+ ions emission quenched, while the CDs emission at 405 nm retained unchanged, based on this, we designed the off-on-off ratiometric fluorescence platform for ALP sensing. The experiment result shows that the ratio of F574/F405 is linear to the concentration of ALP in arange of 0.05∼3000 U/L with a detection limit of 0.04 U/L, which is comparable or better than those reported fluorescence probe, especially the calibrated signal introduction of CDs can eliminate the background interference, improve the accuracy of proposed probe greatly. Furthermore, the discrimination of ALP enzyme inhibitor with the IC50 of 26 μM, and ALP concentration in real human serum sample has also demonstrated the applicability of CDs@YVO4: Dy3+ fluorescence sensor well.

Vanadate contaminant in groundwater receives increasing attentions, but little is known on its biogeochemical transformation with gaseous electron donors. This study investigated bio-reduction of vanadate coupled with anaerobic methane oxidation and its relationship with nitrate reduction. Results showed 95.8 ± 3.1% of 1 mM vanadate was removed within 7 days using methane as the sole electron donor. Tetravalent vanadium compounds were the main reduction products, which precipitated naturally in groundwater environment. The introduction of nitrate inhibited vanadate reduction, though both were reduced in parallel. Accumulations of volatile fatty acids (VFAs) were observed from methane oxidation. Preliminary microbial community structure and metabolite analyses indicated that vanadate was likely reduced via Methylomonas coupled with methane oxidation or through synergistic relationships between methane oxidizing bacteria and heterotrophic vanadate reducers with VFAs served as the intermediates.

We aimed to study the effect of vanadium(V) exposure on cell viability, nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) and to elucidate if these effects can be reverted by co-exposure to V and manganese (Mn). HepG2 cells were incubated with various concentrations of bis(maltolato)oxovanadium(IV) or MnCl2 for 32 h for viability study. The higher concentrations (59 μM V, 54 nM Mn and 59 μM V+54 nM Mn) were used to study DNA damage and uptake of V and Mn. Comet assay was used for the study of nDNA damage; mtDNA damage was studied by determining deletions and number of copies of the ND1/ND4 mtDNA region. Cellular content of V and Mn was determined using ICPMS. Cellular exposure to 59 μM V decreased viability (14%) and damaged nDNA and mtDNA. This effect was partially prevented by the co-exposure to V + Mn. Exposure to V increased the cellular content of V and Mn (812.3% and 153.5%, respectively). Exposure to Mn decreased the content of V and Mn (62% and 56%, respectively). Exposure to V + Mn increased V (261%) and decreased Mn (56%) content. The positive effects on cell viability and DNA damage when incubated with V + Mn could be due to the Mn-mediated inhibition of V uptake.

Protein tyrosine phosphatase of regenerating liver (PRL) is a group of phosphatases that has not been broadly studied in protozoan parasites. In humans, PRLs are involved in metastatic cancer, the promotion of cell migration and invasion. PTPs have been increasingly recognized as important effectors of host-pathogen interactions. We characterized the only putative protein tyrosine phosphatase PRL (PTP EhPRL) in the eukaryotic human intestinal parasite Entamoeba histolytica. Here, we reported that the EhPRL protein possessed the classical HCX5R catalytic motif of PTPs and the CAAX box characteristic of the PRL family and exhibited 31-32% homology with the three human PRL isoforms. In amebae, the protein was expressed at low but detectable levels. The recombinant protein (rEhPRL) had enzymatic activity with the 3-o-methyl fluorescein phosphate (OMFP) substrate; this enzymatic activity was inhibited by the PTP inhibitor o-vanadate. Using immunofluorescence we showed that native EhPRL was localized to the cytoplasm and plasma membrane. When the trophozoites interacted with collagen, EhPRL relocalized over time to vesicle-like structures. Interaction with fibronectin increased the presence of the enzyme in the cytoplasm. Using RT-PCR, we demonstrated that EhPRL mRNA expression was upregulated when the trophozoites interacted with collagen but not with fibronectin. Trophozoites recovered from amoebic liver abscesses showed higher EhPRL mRNA expression levels than normal trophozoites. These results strongly suggest that EhPRL may play an important role in the biology and adaptive response of the parasite to the host environment during amoebic liver abscess development, thereby participating in the pathogenic mechanism.

Background Estrogen deficiency and increase in protein tyrosine phosphatase (PTPase) activity may be a key mechanism in postmenopausal dyslipidemia–induced vascular dysfunction and dementia. Thus, the present study has been designed to investigate the effect of biochanin A (BCA, a phytoestrogen) and sodium orthovanadate (SOV), an inhibitor of PTPase in dyslipidemia-induced vascular dementia in ovariectomized rats. Methods Female Wistar rats were ovariectomized and fed on high fat diet for 4 weeks to produce dyslipidemia. Dyslipidemia was assessed by estimation of serum lipid levels including total cholesterol, triglyceride, HDL, and LDL levels. Dementia was assessed in terms of increase in brain acetylcholinesterase (AChE) activity and attenuation of learning ability (escape latency time) and memory retention (time spent in target quadrant) using Morris water maze. Vascular dysfunction was assessed in terms of attenuation of acetylcholine-induced endothelium-dependent relaxation (isolated carotid ring preparation), mRNA expression of endothelial nitric oxide synthase, and increase in serum thiobarbituric acid reactive species, superoxide anion level. Neurodegeneration was assessed in hippocampus by hematoxylin and eosin staining. BCA (2.5 and 5 mg/kg) and SOV (5 and 10 mg/kg) were administered alone and in low-dose combination to ovariectomized dyslipidemic rats. Results BCA (2.5 and 5 mg/kg), SOV (5 and 10 mg/kg), and donepezil (1 mg/kg) significantly improves vascular function, and learning and memory ability and decreases the neuronal cell death, oxidative stress, and AChE in ovariectomized dyslipidemic rats. Conclusions Thus, it may be concluded that BCA and SOV attenuate vascular dysfunction and dementia in dyslipidemic ovariectomized rats.

Vanadium has been emerged as a promising agent owing to its ability to prevent several types of cancer. This study was aimed to investigate the protective role of an organovanadium complex, viz., oxovanadium(IV)-L-cysteine methyl ester (VC-IV) against cyclophosphamide (CP)-induced hepatotoxicity and genotoxicity in mice. Oral administration of VC-IV quite effectively ameliorated CP-induced histopathological lesions and reduced levels of alanine transaminase, aspartate transaminase and alkaline phosphatase. In addition, VC-IV significantly attenuated CP-induced oxidative stress in the liver as evident from levels of reactive oxygen species, nitric oxide and lipid peroxidation. Restoration of glutathione level and activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase) were also observed upon VC-IV administration. Moreover, VC-IV significantly mitigated CP-induced chromosomal aberrations, micronuclei formation, DNA fragmentation and apoptosis in bone marrow cells and DNA damage in lymphocytes. The present study showed that VC-IV could provide adequate protection against CP-induced hepatotoxicity and genotoxicity in vivo.