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High northern latitudes are climatic sensitive areas, and are also regions to which polycyclic aromatic hydrocarbons (PAHs) easily transport and accumulate with potential risk to natural ecosystems. However, the effect of PAHs on northern woody plant growth and defense under climate change is very little studied. Here, we conducted a unique experiment in greenhouses to investigate sex-related responses of the dioecious Populus tremula to pyrene (50 mg kg −1 ) and residue of pyrene in soils under ambient and elevated temperature (+1.8 °C on average) and CO 2 (740 ppm). Pyrene decreased stem biomass and leaf area by 9% and 6%, respectively under ambient conditions, and the reduction of leaf area was more severe under elevated temperature (38%), elevated CO 2 (37%), and combined T + CO 2 (42%). Other growth parameters were unchanged by pyrene. Pyrene did not affect the concentration of leaf total phenolics under ambient conditions, but increased it by 16%, 1%, and 20% compared to controls under elevated temperature, elevated CO 2 , and T + CO 2 , respectively. Pyrene had only minor sex-specific effects on plant growth and phenolics. The concentration of residual pyrene in pyrene-spiked soils was higher under elevated CO 2 than under ambient, elevated temperature, and combined T + CO 2 . The results suggest that both sexes of P. tremula have the capacity to regulate growth and metabolism to adjust to the stress of the tested pyrene contamination under elevated temperature and CO 2 , but potential risk of pyrene to plants still exists in the future changing climate. [ABSTRACT FROM AUTHOR]

The combined effects of climate change and chemical contaminants on plant performance are still not well understood. Especially, whether different sexes of dioecious plants respond differently to combined stresses is unknown. In order to study the sex-related responses of European aspen to soil nTiO 2 contamination (0, 50, 300 mg kg –1 ) under elevated temperature (+1.6 °C) and CO 2 (730 ppm), we conducted a study in greenhouses. Ti accumulated in roots exposed to nTiO 2 (1.1–3.3 and 2.7–21.1 mg kg –1 in 50 and 300 mg kg –1 treatments, respectively). Elevated CO 2 had no effects on Ti uptake, while elevated temperature increased it in the 300 mg kg –1 treatment. Males grew taller than females under ambient conditions, but females had greater height and biomass increment under elevated temperature. In all climate treatments, nTiO 2 increased leaf phenolics in females by 12–19% and 15–26% at 50 and 300 mg kg –1 , respectively. Leaf phenolics decreased under elevated temperature, but increased under elevated CO 2 in both sexes. Results suggest that females have better chemical defense against nTiO 2 than males under future climate conditions. In the longer run, this may cause changes in the competitive abilities of both sexes, which again may affect sex ratios and genetic variation in nature. [ABSTRACT FROM AUTHOR]

Modification of calcium carbonate particles with surfactant significantly improves the properties of polyvinyl chloride (PVC). Hydrophobic spherical CaCO 3 particles were prepared in the presence of dodecyl dihydrogen phosphate (DDP) by a carbonation method. In the process, DDP was used as an organic substrate to induce the nucleation and growth of calcium carbonate. The operating parameters such as temperature and the dosage of the organic substrate were varied to study their influences on the active ratio and contact angle of calcium carbonate particles. The surface property of CaCO 3 particles was changed from hydrophilic to hydrophobic when the dosage of DDP to CaCO 3 changed from 0 to 2%. The contact angle of modified CaCO 3 particles was 119.51°. Moreover, X-ray diffraction (XRD), FT-IR spectrums and thermogravimetry analysis (TGA) were employed to characterize the obtained products. The schematic illustration for interaction between the organic substrate and inorganic mineral in aqueous medium was showed in the end. The synthesized CaCO 3 was applied to polyvinyl chloride (PVC) to improve its mechanical properties. The properties of PVC/CaCO 3 composites have been tested such as tensile strength, impact strength, Young's modulus and SEM. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanoparticles (nTiO 2 ) have the potential to adsorb co-existing contaminants in aqueous environment to form nanoparticle-contaminant complexes. Adsorption by nTiO 2 might impact the fate of contaminants in water. Bioaccumulation experiments were conducted to compare the accumulation of polybrominated diphenyl ethers (PBDEs) in marine bivalve ( Scapharca subcrenata ) exposed to PBDEs in the presence and absence of nTiO 2 . PBDEs can be taken up by S. subcrenata through aqueous exposure. nTiO 2 acts as a carrier and can enhance the ingestion of PBDEs, but the bioaccumulation of PBDEs was not facilitated significantly in the presence of nTiO 2 . Similar accumulation kinetics pattern was found after exposing to PBDEs in the presence and absence of nTiO 2 . Further analysis showed that no significant difference between the congener profiles of PBDEs in the presence and absence of nTiO 2 , suggesting that nTiO 2 would not influence the biotransformation of PBDEs in clams. [ABSTRACT FROM AUTHOR]

• Primary liver malignancy accounts to be one of the most noxious disease menacing global populations. • vicenin-2 effectively inhibited both constitutive and stimulated STAT3 phopshorylation and inhibited the activation of JAK. • vicenin-2 persuasively indued apoptosis in tumour cells thereby renders anticarcinogenic effect on hepatocarcinoma cells. We analyzed the potency of vicenin-2, flavanoid present in medicinal herbs such Ocimum sanctum and Moringa oleifera on inhibiting the STAT3 gene expression and its subsequent regulatory genes. We assessed the effect of vicenin-2 against the STAT-3 activation both in the normal and induced stage with IL-6 and EGF. To prove vicenin-2 as a ideal inhibitor of vicenin-2, the STAT3 regulated proteins, protein kinases and phosphatases were also analyzed. The anticancer effect of vicenin-2 was assessed with three different hepatocellular carcinoma cell lines and their effect of induction of apoptosis was assessed with immunoblotting analysis. To confirm the anticancer effect of vicenin-2, the xenografted hepatocellular mice model was treated with vicenin-2 and analyzed for tumor size reduction and apoptotic induction. Vicenin-2 significantly inhibited the STAT3 protein expression even in the presence of IL-6 and EGF induction. Vicenin-2 pretreated cells shown increased phosphorylation of STAT3 protein when treated with pervandate and SHP1-siRNA respectively. Vicenin-2 treatment decreased the expression of STAT3 regulated protein JAK1, JAK2, AKT and also increased the apoptotic proteins procaspase3, PARP. It significantly decreased the levels of antiapoptotic proteins Bcl2, Bclxl, Mcl1, survivig, cell regulatory protein cyclinD1 and angiogenic protein VEGF. In vivo results prove that vicenin-2 potentially inhibits the growth of tumour and induces apoptosis in xenografted hepatocellular mice model. Overall our in vitro and in vivo findings authentically prove that vicenin-2 is a novel STAT-3 inhibitor which imparts anticarcinogenic effect by inhibiting the STAT-3 signaling pathway. [ABSTRACT FROM AUTHOR]

Future climatic changes may alter the balance between the sexes of dioecious species due to differential effects on resource allocation to growth and defense. Our purpose was to study the impacts of elevated temperature and CO 2 concentration on the relative changes in growth and phenolics accumulation in stem bark of the dioecious Populus tremula , a keystone species for boreal forest biodiversity and one that is browsed by many mammalian herbivores. In a greenhouse experiment, four female and four male genotypes of P. tremula were grown under single and combined treatments of elevated temperature (1.5 °C on average) and CO 2 concentration (720 ppm) for one growing season. Elevated temperature increased the height, diameter, leaf and stem biomass, and in addition decreased the concentration of phenolics including salicylates, flavonoids, phenolic acids, salireposide and lignan. Elevated CO 2 concentration, on the other hand, reduced the height growth (other growth parameters were unchanged) and increased the concentration of phenolics, especially salicylates and phenolic acids. In the combined treatment, P. tremula tended to grow more, but elevated temperature counteracted the effect of elevated CO 2 concentration on phenolics accumulation. Although statistically not significant, males tended to have greater growth and a lower level of phenolics than females. The smaller sexual differences were also not strongly affected by climatic factors. Under future elevated temperature and CO 2 concentration, both sexes of P. tremula will probably grow more and possibly accumulate lower levels of phenolics, but intersexual differences in growth and phenolics accumulation may be more pronounced after sexual maturation. [ABSTRACT FROM AUTHOR]

The APOBEC proteins play significant roles in the innate and adaptive immune system, probably due to their deaminase activities. Because APOBEC1 (A1) and APOBEC3 (A3) are absent in the chicken genome, we were interested in determining whether chicken APOBEC4 (A4) possessed more complex functions than its mammalian homologs. In this study, chicken A4 (chA4) mRNA was identified and cloned for the first time. Based on bioinformatics analyses, the conserved zinc-coordinating motif (HXE ... PC(X) 2–6 C) was identified on the surface of chA4 and contained highly conserved His97, Glu99, Pro130, Cys131 and Cys138 active sites. The highest expression levels of constitutive chA4 were detected in primary lymphocytes and bursa of Fabricius. Newcastle Disease (ND) is one of the most serious infectious diseases in birds, causing major economic losses to the poultry industry. In vitro , Newcastle Disease Virus (NDV) early infection induced significant increases in chA4 expression in the chicken B cell line, DT40, the macrophage cell line, HD11 and the CD4+ T cell line, MSB-1, but not the fibroblast cell line, DF-1. In vivo , the expression levels of chA4 were up-regulated in several tissues from NDV-infected chickens, especially the thymus, testicles, duodenum and kidney. The high level expression of exogenous chA4 displayed inhibitory effects on NDV and reduced viral RNA in infected cells. Taken together, these data demonstrate that chA4 is involved in the chicken immune system and may play important roles in host anti-viral responses. • First time isolation and identification of chicken APOBEC4. • chA4 contains typical APOBEC motifs and probably has catalytic activity. • The highest expression levels of constitutive chA4 were detected in primary lymphocytes and bursa of Fabricius. • NDV infection induces significant increases in chA4 expression in immune cells and in the tissues of infected chickens. • chA4 expression induces inhibitory effects on NDV. [ABSTRACT FROM AUTHOR]

This paper reports a facile synthesis of bimetallic Au x Pt y nanozyme using C-rich oligonucleotide as the nucleation template, with high peroxidase-like activity and thiophilicity associated with the ratio of x : y . The efficient Au 2 Pt 1 nanozyme possesses highly peroxidase mimicking activity with the K m value of 0.088 mM toward 3,3′,5,5′-tetramethylbenzidine and 196 mM toward hydrogen peroxide. It is the first report to explore colorimetric assays for biothiols with high sensitivity and selectivity against non-thiol-containing amino acids, on the basis of thiol-induced inhibition of peroxidase-like activities of metal nanoparticles. By using Au 2 Pt 1 nanozyme, the limit of detection (LOD) is 3.5 nM for cysteine and 1.6 nM for homocysteine. This DNA-stabilized bimetallic Au x Pt y nanozyme shows a promising application in quantitative detection of biothiols in biological fluids. [ABSTRACT FROM AUTHOR]