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The rhizosphere microbiome plays an important role in plant growth and behavior during phytoremediation. This work aims to explore how hyperaccumulating plant performance (shoot biomass and Cd uptake) and rhizosphere bacterial community are driven by plant development under a Cd concentration gradient and their relationship during plant growth. A pot experiment was conducted using the Cd hyperaccumulator Sedum plumbizincicola grown in soil spiked with 0, 5 and 20 mg Cd kg−1 for 13 weeks. Plant performance (shoot biomass and Cd uptake) was determined and the rhizosphere bacterial community was examined by weekly Illumina sequencing. Biomarker genera were identified by the Random Forest model and the functions were predicted by PICRUSt2. The rhizospheres bacterial community tended to stabilize from the 6th or 7th week regardless of the soil Cd concentration, coinciding with the vigorous growth stage of the hyperaccumulator. Biomarker genera Paenibacillus and Streptacidiphilus enriched in the stable stage showed significant positive correlations with Cd uptake. In addition, some predicted gene abundances of enzymes related to plant growth promotion by the rhizosphere bacterial community were influenced to various degrees by plant development and soil Cd concentration. There exists a stable bacterial community in the rhizosphere of S. plumbizincicola during phytoremediation and biomarker taxa enriched at this stage were positively correlated with Cd uptake. Selecting microorganisms that match the developmental stages might further enhance phytoremediation. This provides some theoretical basis for modulating rhizosphere microbes at the appropriate time during phytoextraction to optimize the phytoremediation technique.

This work describes an eco-friendly approach for in situ immobilization of Cu nanoparticles on the surface of lignin modified Fe3O4 nanoparticles, without using any toxic reducing and capping agents. The structure, morphology, and physicochemical properties were characterized by various analytical techniques such as Fourier transformed infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), inductively coupled plasma (ICP) and vibrating sample magnetometer (VSM). The Fe3O4/Lignin/Cu NPs was proven to be highly efficient nanocatalyst for reduction of nitroarenes. The reaction was performed in water medium and excellent yields of the products were achieved. The nanocatalyst was easily magnetically recovered and recycled 8 times without any significant loss of catalytic activity. While studying the biological activity, cell viability of Fe3O4/Lignin/Cu NPs was very low against A549 lung cancer cells without any cytotoxicity on the normal cell line. The viability of lung cancer cell line reduced dose-dependently in the presence of Fe3O4/Lignin/Cu nanocomposite. The IC50 of Fe3O4/Lignin/Cu nanocomposite was32 µg/mL against A549 cell line.

Background Long non-coding RNA (lncRNA) distal-less homeobox 6 antisense 1 (DLX6-AS1) was reported to be dysregulated in lung cancer. However, detailed roles of DLX6-AS1 in the pathogenesis of non-small cell lung cancer (NSCLC) were largely unknown. Methods The expression of DLX6-AS1 was measured in NSCLC tissues and cells by quantitative real-time PCR (qRT-PCR). The abundance of proline rich 11 (PRR11) were detected by qRT-PCR and western blot, respectively. The effects of DLX6-AS1 and PRR11 on cell proliferation, migration, invasion and apoptosis were explored by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), transwell and flow cytometry analysis, respectively. Luciferase reporter assay, qRT-PCR and western blot were performed to confirm the interaction between miR-144 and DLX6-AS1 or PRR11. Tumor xenograft assay was performed to verify the role of DLX6-AS1 in NSCLC in vivo. Results DLX6-AS1 and PRR11 were elevated in NSCLC tissues and cells. DLX6-AS1 was positively correlated with PRR11 mRNA expression in NSCLC tissues. Knockdown of DLX6-AS1 and PRR11 significantly suppressed cell proliferation, migration and invasion and induced apoptosis in NSCLC cells, which was reversed by PRR11 overexpression. In addition, DLX6-AS1 and PRR11 were demonstrated to interact with microRNA-144 (miR-144) and DLX6-AS1 upregulated PRR11 expression by acting as a competing endogenous RNA (ceRNA) of miR-144 in NSCLC cells. Furthermore, DLX6-AS1 knockdown suppressed tumor growth in NSCLC in vivo by upregulating miR-144 and downregulating PRR11. Conclusion Knockdown of DLX6-AS1 inhibited cell proliferation, migration, invasion and promoted apoptosis by downregulating PRR11 expression and upregulating miR-144 in NSCLC.

BACKGROUND Most studies on immunocastration currently focused on male animals. However, immunization of male animals does not completely inhibit sexual behavior and fertility. This study aimed to compare the immunocastration effect of KISS1 DNA vaccines encoding different lengths of kisspeptins in female rats for effective castration effects on both male and female rats. METHODS Fifteen female rats were randomly divided into three groups. The rats in T1 group or T2 group was orally given respectively KISS1-54 or KISS1-10 DNA vaccines with fused tPA signal peptide, and the control group (Group C) was orally administered with empty vector vaccine, at a dose of 5 × 109 CFU/rat at weeks 0, 3 and 6 of the study. Blood samples were collected by retroorbital bleeding before primary immunization and at weeks 3 and 9 after primary immunization. RESULTS Both KISS1-54 and KISS1-10 DNA vaccines induced the body's humoral immune response, and the anti-kisspeptin antibody titres in the T1 group were significantly higher than that in T2 and C groups (p

Indoleacetic acid (IAA) is a plant growth regulator that plays an important role in plant growth and development, and participates in the regulation of abiotic stress. To explore the effect of IAA on cadmium toxicity in Cinnamomum camphora, an indoor potted experiment was conducted with one-year-old C. camphora seedlings. The influence of IAA on cadmium accumulation, net photosynthetic rates, respiration, photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll and carotenoids), osmoregulatory substances (proline, soluble sugar and soluble protein) and the malondialdehyde content in C. camphora leaves treated with 30 mg kg−1 cadmium was analysed with or without the addition of 10 mg kg−1 IAA. Cadmium accumulation in the leaves of C. camphora with the addition of exogenous IAA was significantly higher than accumulation during cadmium stress without additional IAA (ca 69.10% after 60 days' incubation). During the culture period, the net photosynthetic rate in C. camphora leaves subjected to cadmium stress without the addition of IAA was up to 24.31% lower than that of control plants. The net photosynthetic rate in C. camphora leaves subjected to cadmium stress and addition of IAA was up to 30.31% higher than that of leaves subjected to cadmium stress without the addition of IAA. Chlorophyll a, total chlorophyll and carotenoid contents in the cadmium-stressed leaves without the addition of IAA were lower than those in the control treatment. The presence of IAA increased the chlorophyll a, total chlorophyll and carotenoid contents relative to the cadmium stress without the addition of IAA. The respiration rate and concentrations of proline, soluble sugar, soluble protein and malondialdehyde in C. camphora leaves subjected to cadmium stress without the addition of IAA were higher than those in the control. The addition of IAA reduced the respiration rate, and the concentrations of proline, soluble sugar, soluble protein and malondialdehyde in C. camphora leaves when compared with the cadmium stress without the addition of IAA. These results indicate that exogenous IAA improves photosynthetic performance and the growth environment of C. camphora by enhancing the net photosynthetic rate, increasing concentrations of osmoregulatory substances, removing reactive oxygen radicals and eliminating potential damage, thereby reducing the toxic effects of cadmium on C. camphora.

Hepatitis B virus X protein (HBx), encoded by the hepatitis B virus (HBV) genome, plays a pivotal in mediating pathogenicity in liver diseases. However, the underlying mechanisms are still needed to be elucidated. Receptor-interacting protein 1 (RIP1) has been identified as a serine/threonine kinase with various biological functions in cell fate, proliferation, and death. In the current study, we found that overexpression of HBx in LO2 human normal hepatocytes increased the expression of RIP1. Importantly, our results indicate that blockage of RIP1 using its specific antagonist necrostatin-1 (Nec-1) ameliorated HBx-induced oxidative stress by mitigating the production of ROS and Nox-4 expression. Also, the presence of Nec-1 improved HBx-induced mitochondrial dysfunction by increasing MMP. Importantly, we found that Nec-1 could inhibit the production of pro-inflammatory cytokines IL-6, IL-8, and CXCL2 as well as the secretion of HMGB1. Mechanistically, we found that Nec-1 treatment suppressed the activation of the JNK/AP-1 and NF-κB signalling pathways. Our findings implicated a novel biological function of RIP1 in HBx-induced cytotoxicity and inflammation in human normal hepatocytes. Antagonism of RIP1 might be a potential therapeutic approach for the treatment of HBV-associated liver diseases.

Gravity-driven membrane (GDM) filtration is promising for decentralized drinking water treatments. To improve the permeability and permeate quality of GDM process, three GDM systems (in-line coagulation system, pre-coagulation system, and system without coagulation as control) were operated in parallel at 65 mbar for 63 days to evaluate the effects of coagulation on flux development, permeate quality, composition and structure of the biofouling layer. The optimal dose of coagulant (polyaluminium chloride) was determined as 4 mg/L. The stable flux increased by 140% and 210% in the in-line coagulation and pre-coagulation systems compared to that of the control system, respectively. Dissolved organic compounds were removed by 31.9% and 29.4% in the in-line coagulation and pre-coagulation systems, while the control system showed a poor removal efficiency (5%). The effective removal of organics from raw water by coagulation resulted in less substrates available in the biofouling layers, thus affecting the production of extracellular polymeric substances (EPS) by limiting the biological processes. The EPS content in the biofouling layer of pre-coagulation system was the lowest, consistent with the highest flux. And such nutrient-poor biofouling layers modified the microbial community, changing the dominant bacteria from Firmicutes to Actinobacteria, thereby affecting the flux. Loose and heterogeneous biofouling layers with numerous holes and cracks were observed under coagulation conditions, which was conducive to the passage of water. All systems exhibited excellent ammonia removal efficiency (96%), but coagulation extended the start-up time for nitrification from 3 days to 5 days. Overall, these results demonstrate that coagulation can improve the GDM filtration performance, and the pre-coagulation system is globally optimal.

The Phytotoxicity of and mechanism underlying selenite-mediated tolerance to Cd stress in Typha angustifolia were studied hydroponically with respect to metal uptake and translocation, photosynthesis-related parameters, contents of proline and O2•ˉ, products of lipid peroxidation, cell viability, enzymatic and non-enzymatic antioxidants, glyoxalases and phytochelatins. T. angustifolia were exposed to 25, 50 and 100 μM of Cd alone and in conjunction with 5 mg L−1 of selenite in full-strength Hoagland's nutrient solution for 30 days. Results showed that Cd contents in T. angustifolia leaves and roots increased in a dose-dependent manner and were higher in roots, but those of BAC, BCF and TF changed in a contrary pattern. Addition of selenite to Cd-containing treatments further reduced Cd levels in T. angustifolia leaves and roots, as well as BAC, BCF and TF. A diphasic effect was found in T. angustifolia for the contents of total chlorophyll, GSH, PC and GSSG, as well as activities of CAT, POD, SOD and GR, in response to Cd stress alone and in conjunction with selenite supplementation, but the same effect was not observed for Pn, Cond, Tr, Ci, Fv/Fm and ϕPSII. In contrast, exogenous selenite supplementation enhanced the contents of total chlorophyll and the non-enzymatic antioxidants, as well as activities of enzymatic antioxidants, while the values of photosynthetic fluorescence parameters were rescued. Selenite addition decreased Cd-induced cell death. Proline contents and Gly I activities in T. angustifolia leaves kept increasing in a dose-dependent manner of Cd concentrations in the growth media and selenite addition further enhanced both parameters. Addition of selenite could quench Cd-mediated generation of MDA, O2•ˉ and MG in T. angustifolia leaves and reduce Cd-induced Gly II activity. A U-shaped GSH/GSSG ratio in T. angustifolia leaves suggests a possible trade-off between PC synthesis and GR activity since both share the same substrate GSH. Therefore, confined BAC, BCF and TF were a mechanism that confers T. angustifolia tolerance to Cd stress, and that exogenous selenite supplementation could depress Cd-induced stress in T. angustifolia by rescuing the photosynthetic fluorescence, enhancing non-enzymatic and enzymatic antioxidants that scavenge O2•ˉ and MG, and potentiating PC synthesis that chelates Cd.

Four gramineous energy plants, Miscanthus sacchariflorus, M. floridulus, Phragmites australis, and Arundo donax were grown on copper tailings in the field for four years. Their phytoremediation potential was examined in terms of their effects on the fractions of heavy metals and soil enzyme activities. Results showed that plantation of these four gramineous plants has improved the proportion of organic material (OM)-binding fraction of heavy metals in copper tailings as a whole, and reduced the proportion of exchangeable and residual fractions. In particular, M. sacchariflorus growth improved significantly the proportion of the OM-binding fractions of Cu (1.73 times), Cd (1.71 times), Zn (1.18 times), and Pb (3.14 times) (P < 0.05) and reduced markedly the residual fractions of Cu (64.45%), Cd (82.38%), Zn (61.43%), and Pb (73.41%) (P < 0.05). Except for A. donax, the growth of other three energy plants improved the activity of phosphatase, urease and dehydrogenase in copper tailings to some extent. In particular, the activity of soil phosphatase and urease in planted tailings differed significantly from that of control (P < 0.05). The effect of M. sacchariflorus growth on soil enzyme was the highest, followed by P. australis, M. floridulus, and A. donax. The content of each heavy metal fraction in soil was correlated with soil enzyme activities, especially the content of OM-binding fraction, which correlated significantly with the activities of phosphatase, urease and dehydrogenase in soil. According to the effects of four gramineous plants growth on activity of soil enzymes and fractions of heavy metals, M. sacchariflorus had the optimal effects for phytoremediation. Therefore, M. sacchariflorus was a candidate plant with great potential for the revegetation of heavy metal tailings.

Background: Radiotherapy is a standard treatment for a significant fraction of cancer patients. Nonetheless, to this day radiation resistance is a key impediment in gastric cancer (GC) treatment. Moreover, GC is characterized by its substantial neo-angiogenesis, driven by high levels of vascular endothelial growth factor (VEGF) correlated with the presence of stomach cancer. The aim of our study was to address if VEGFR inhibitors treatments impact the negative effect of radiotherapy regiments of gastric cancer. Materials and methods: Isolation of exosomes released by SGC-7901 and BGC-823 lines after irradiation at 0 Gy or 6 Gy was performed by differential ultra-centrifugation. Incubation of Human Umbilical Vein Endothelial Cells (HUVEC) was carried out with different concentrations of exosomes from non- or irradiated GC cells to address their proliferation and survival fraction (SF) by MTS. 6 Gy irradiated cells exosomes at concentration of 20 µg/ml were compared to EC incubated with the same exosome concentration from non-irradiated human GC cells over 72-hour time course. Wound-healing and Transwell assays were performed in a migration buffer consisting of exosomes released by non- or irradiated SGC-7901 and BGC-823 cells over 24-hour time course. HUVEC cells stained with DAPI that have passed through a gluten gel were counted in order to monitor their invasion capacity. Employing IC50, 60 µg/ml was determined as the optimal Apatinib (YN968D1) concentration for the half-life of HUVEC, and incubated with exosomes from irradiated GC cells. The aforementioned assays were performed in the background of the same conditions in order to analyse the effect of Apatinib on HUVEC progression. Results: We show that proliferation, motility and invasive capacity of HUVEC are enhanced upon incubation with exosomes released by irradiated GC cell lines. Importantly, the latter is counteracted by the VEGFR-2 inhibitor Apatinib which hinders ECs progression. Conclusion / Significance: Combining radiotherapy and VEGFR inhibitors treatment can provide potentially a substantial impact in decreasing cancer death rates by averting the negative effect of radiotherapy regiments and provide better standard for cancer patients.

The objective of this study was to establish the effects of cold expansion, chamfering, bolt clamping, and their combinations on the fatigue life of an aluminum–lithium alloy single plate. Fatigue tests were conducted to quantify the anti-fatigue effects of the different techniques. A scanning electron microscope was used to perform fracture analyses of the used specimens, and the residual stresses were measured using an X-ray diffraction device. In addition, three-dimensional finite element models of the specimens were established and used to characterize their stress states, and the Smith–Watson–Topper method was used to predict the fatigue lives of the specimens. The fatigue test results showed that all the considered processes improved the fatigue life of the pristine specimen. The most effective was a combination of 3.2% cold expansion, 1-mm chamfering, and bolt clamping using a 6.4-N m torque, which improved the fatigue life of the pristine specimen by a factor of 15.5. The finite element method results also revealed that this combination decreased the maximum stress and confirmed its superiority in relation to the other fatigue-life enhancement techniques in terms of the anti-fatigue effect. The Smith–Watson–Topper method underestimated the specimen fatigue life, but the accuracy satisfied engineering requirements.

Cold expansion and interference fitting both can improve the fatigue life of 7075-T6 aluminum alloy single plates. To study the combination effect of the two techniques on fatigue life improvement, a numerical analysis method was employed to simulate the specimens with different cold expansion and interference fit degrees. Finite element methods were conducted to capture the residual stress, and the Smith-Watson-Topper (SWT) method was used to predict the fatigue life. The simulation results revealed that, compared with single technique enhanced specimens, the combined enhanced specimens of 4% cold expansion and 2% interference fit increase the fatigue life by 12–38%.

This paper focuses on the phytoaccumulation and translocation of copper (Cu) in rape grown in the Cu-polluted paddy soil. Pot experiments were conducted in greenhouse conditions to examine the Cu availability and uptake by rape in a paddy soil. The soil was spiked with different concentrations of Cu (0, 100, 300, 500 and 1,000 mg kg−1 soil, added as CuSO4) to simulate soil Cu contamination. After 8 months of growth, plant shoots, stems, pod shells and rapeseeds were harvested for analysis. The concentrations of Cu in the roots and aerial parts of the rape and available Cu in soils were then extracted and determined. Chemical fractions of Cu in the paddy soil of rape were also investigated by sequential extraction techniques. The findings showed that Cu in the clean paddy soil was mainly distributed in residual fractions. However, the most drastic increase was observed in Fe–Mn oxides-bound fractions and organic-bound fractions with increasing soil Cu concentrations. Exchangeable fractions played a more important role than other fractions in controlling the mobility and phytoavailability of Cu. Rape growth was stimulated by low concentrations of Cu, but inhibited by high concentrations. Compares to the aerial parts, the roots were more sensitive to Cu toxicity. The correlation analysis showed that Cu in exchangeable fractions made the greatest contribution on the accumulation of Cu in rapes. The factor analysis results showed that the exchangeable fractions in roots can be indicator of Cu availability. Meanwhile, the bio-concentration factors and the translocation factors of Cu in rape were determined and the results showed that Cu had lower accumulation in the edible parts of the rape.

In the original proposal of Wayne et al. (Int J Syst Bacteriol 37:463–464, 1987), two measures of genetic relatedness were proposed to set the boundary for prokaryotic species. The first was the change in the melting temperature (ΔTm) of heteroduplex DNA and the second was the extent of DNA–DNA hybridization (DDH). While this approach was justified given the experimental error inherent in these methods, genomic sequencing has the potential to measure both parameters with great precision. The average nucleotide identity (ANIb), a surrogate for the ΔTm, and the calculated DDH (cDDH) were determined from the complete genomes of representatives of 17 genera of prokaryotes. When the ANIb was >75 %, the ratio (100-cDDH)/(100-ANIb) was 3.69 ± 0.93 (± SD) and varied from about 2.35 to 4.59 between genera. The differences among genera was highly significant (p

The effects of copper accumulation and resistance in two biotypes of Cynodon dactylon were studied. Results showed that at a low concentration of copper (

Miscanthus sacchariflorus (Maxim.) Benth. is a metallophyte suitable for the phytoremediation of mine wastes. The tolerance and accumulation of M. sacchariflorus to cadmium was studied by pot experiments. The results showed that O2·- generation rate, plasma membrane permeability and MDA content of M. sacchariflorus leaves increased with increasing Cd concentrations in soil, but significant effect was only observed when Cd concentrations were ≥50 mg·kg(-1). SOD and POD activities increased initially but decreased later on, whereas CAT activity only increased significantly at higher Cd concentrations, 50-100 mg·kg(-1). The content of photosynthetic pigment and growth of M. sacchariflorus were both not significantly affected when Cd concentration was ≤25 mg·kg(-1). In contrast, both parameters were significantly affected when Cd concentration was ≥50 mg·kg(-1). M. sacchariflorus could accumulate much Cd, but most of the Cd assimilated was retained in the belowground part, suggesting that M. sacchariflorus has poor ability to translocate Cd to the aboveground part. Our results suggested that although M. sacchariflorus was not a hyper-accumulator, it has a strong capacity to tolerate and stabilize the Cd. Therefore, M. sacchariflorus has a certain potential in the phytostabilization of Cd-contaminated soils.

Prokaryotic genomes are diverse in terms of their nucleotide and oligonucleotide composition as well as presence of various sequence features that can affect physical properties of the DNA molecule. We present a survey of local sequence patterns which have a potential to promote non-canonical DNA conformations (i.e. different from standard B-DNA double helix) and interpret the results in terms of relationships with organisms' habitats, phylogenetic classifications, and other characteristics. Our present work differs from earlier similar surveys not only by investigating a wider range of sequence patterns in a large number of genomes but also by using a more realistic null model to assess significant deviations. Our results show that simple sequence repeats and Z-DNA-promoting patterns are generally suppressed in prokaryotic genomes, whereas palindromes and inverted repeats are over-represented. Representation of patterns that promote Z-DNA and intrinsic DNA curvature increases with increasing optimal growth temperature (OGT), and decreases with increasing oxygen requirement. Additionally, representations of close direct repeats, palindromes and inverted repeats exhibit clear negative trends with increasing OGT. The observed relationships with environmental characteristics, particularly OGT, suggest possible evolutionary scenarios of structural adaptation of DNA to particular environmental niches.

This paper studied the transformation of copper fractions in rhizosphere and non-rhizosphere soils of Festuca arundinacea and Trifolium repens in deserted land of copper tailings. The results showed that the proportion of organic-bound or exchangeable contents to the total contents of copper in rhizosphere increased by 9.81 and 10.42%, while the contents of carbonate-bound or Fe–Mn oxides-bound decreased by 2.96 and 1.82%, respectively. The growth and absorption of F. arundinacea and T. repens accelerated the transformation of copper fractions in rhizosphere soils. The effect of root system of T. repens was prominently greater than that of F. arundinacea.

The modified point-ion model has been successfully used to calculated multilayer relaxation on metal surfaces. This model uses a single parameter (alpha) to simulate the unhomogeneous electron density distribution in a semi-infinite metal although its value should fit experimental data for a given material. This model was only used to calculate the semi-infinite metal before, however, it could be applicable for calculating the structure of the thin film consisting of very few atomic layers. As far as our knowledge goes, neither theoretical nor experimental data has been reported in this respect. In this paper, we use this model to calculate preliminarily the thin film structure of some fcc and bcc surfaces.