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Soil salinity, together with zinc (Zn) and manganese (Mn) deficiencies, adversely affects rice growth and yield. The comparative salinity stress mitigation response of rice to Zn or Mn remains largely unknown. Rice cultivars, viz. Basmati-515 and KSK-282, were grown in saline soil having electrical conductivity (EC) of 7.5 dS m−1 (as control) parallel to EC 7.5 dS m−1 + Zn 3.5 mg kg−1 and EC 7.5 dS m−1 + Mn 3.5 mg kg−1 treatments in a pot experiment. Application of Zn in saline soil decreased (p

This study focuses on the synthesis and characterization of Ag nanoparticle-decorated reduced graphene oxide (RGO) nanocomposites (Ag-RGO), which were obtained via a facile, green and efficient one-pot hydrothermal method. TEM results showed that the silver nanoparticles (20-50 nm) were uniformly attached onto RGO sheets with C/O ratio of 6.4 and 80% of sp2 carbon, obtained from XPS analysis. Compared with GO and RGO, the prepared Ag-RGO composites possessed significant antibacterial property; the minimum inhibitory concentration of Ag-RGO was just 31.25 μg/mL against Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli. Particularly, the Ag-RGO nanocomposites released more Ag+ in acidic condition, promoting the produce of reactive oxygen species, which are acknowledged as disruption to the membrane integrity of the bacteria. Moreover, the Ag-RGO nanocomposites effectively dispersed and eliminated the maturely formed biofilm, showing superior advantages in responding to public health threats posed by biofilm-related infections.

Background Due to biomass recalcitrance, including complexity of lignocellulosic matrix, crystallinity of cellulose, and inhibition of lignin, the bioconversion of lignocellulosic biomass is difficult and inefficient. The aim of this study is to investigate an effective and green pretreatment method for overcoming biomass recalcitrance of lignocellulose. Results An effective mechanical activation (MA) + metal salt (MAMS) technology was applied to pretreat sugarcane bagasse (SCB), a typical kind of lignocellulosic biomass, in a stirring ball mill. Chlorides and nitrates of Al and Fe showed better synergistic effect with MA, especially AlCl3, ascribing to the interaction between metal salt and oxygen-containing groups induced by MA. Comparative studies showed that MAMS pretreatment effectively changed the recalcitrant structural characteristics of lignocellulosic matrix and reduced the inhibitory action of lignin on enzymatic conversion of SCB. The increase in hydroxyl and carboxyl groups of lignin induced by MAMS pretreatment led to the increase of its hydrophilicity, which could weaken the binding force between cellulase and lignin and reduce the nonproductive binding of cellulase enzymes to lignin. Conclusions MAMS pretreatment significantly enhanced the enzymatic digestibility of polysaccharides substrate by overcoming biomass recalcitrance without the removal of lignin from enzymatic hydrolysis system. Electronic supplementary material The online version of this article (10.1186/s13068-019-1354-6) contains supplementary material, which is available to authorized users.

Exogenously administered B-type natriuretic peptide (BNP) has been shown to provide cardioprotection against various heart diseases. However, the underlying mechanisms remain elusive. This study explores whether BNP exerts its cardioprotection against hypoxia/reoxygenation (H/R) injury under high glucose/high fat (HG/HF) conditions in cardiac H9c2 cells and uncovers the underlying mechanisms. Our data revealed that BNP significantly increased the cell viability and decreased the release of lactate dehydrogenase (LDH) and creatine kinase (CK), with a maximal effect at the BNP concentration of 10−7 mol/L. In addition, by analyzing the activation of cleaved caspase-3 and by Annexin V-FITC/PI staining, we showed that BNP attenuated H/R-induced cell apoptosis in HG/HF conditions. Western blot analysis showed enhanced phosphorylation of protein kinase RNA (PKR)-like endoplastmic reticulum (ER) kinase (PERK) and eukaryotic initiation factor 2α (eIF2α)(one of the three main signaling pathways in endoplastmic reticulum (ER) stress), and increased expression of GRP78 and CHOP proteins (ER stress-related proteins) in H9c2 cells which underwent H/R in HG/HF conditions. Treatment with BNP or 8-Br-cGMP (an analog of cGMP) reversed this activation. However, this effect was significantly weakened by KT-5823, a selective cGMP-dependent protein kinase G (PKG) inhibitor. In addition, similar to BNP, treatment with a specific inhibitor of ER stress tauroursodeoxycholic acid (TUDCA) protected the cells against H/R injury exposed to HG/HF conditions. In conclusion, these findings demonstrated that BNP effectively protected cells against H/R injury under HG/HF conditions by inhibiting the ER stress via activation of the cGMP-PKG signaling pathway.

Rh substituted-La2B2O7 (B = Zr or Ti) composite oxides were synthesized and applied in the dry reforming of methane (DRM) reaction. The characterizations of XRD, Raman, UV–vis diffuse reflectance, ...

Bone metastasis of colorectal cancer (CRC) cells leads to osteolysis. Aberrant activation of osteoclasts is responsible for bone resorption in tumor. In general, bone marrow-derived monocytes (BMMs) differentiate into osteoclasts, however, how CRC cells interact with BMMs and how to regulate the differentiation is elusive. We here report that CRC cells promote bone resorption in bone metastasis. Transcriptomic profiling revealed CCL3 up-regulated in MC-38 conditional medium treated BMMs. Further investigation demonstrated that CCL3 produced by BMMs facilitated cell infusion and thus promoted the osteoclastogenesis. In addition, CRC cells derived EGF stimulated the production of CCL3 in BMMs through activation of ERK/CREB pathway. Blockage of EGF or CCL3 can efficiently attenuate the osteolysis in bone metastasis of CRC.

Cancer is one of the biggest killers threat to human life and health and is still difficult to treat mainly due to the lack of targeted drug delivery stages and limitations associated with delivering drugs to targeted cancer tissues. The goal of this work was to develop a magnetic, pH-sensitive formulation for targeted delivery of chemotherapeutic agents to cancer cells. Then the functional drug delivery system (Fe

Brain natriuretic peptide (BNP) is an important biological marker and regulator of cardiac function. BNP resistance is characterized by high concentrations of less functionally effective BNP and common in heart failure (HF) patients. However, the roles and consequences of BNP resistance remain poorly understood. Investigate the effects of cardiac BNP resistance and identify potential metabolic biomarkers for screening and diagnosis. Thirty patients and thirty healthy subjects were enrolled in this study. Cardiac functions were evaluated by echocardiography. The plasma levels of cyclic guanosine monophosphate (cGMP) and BNP were measured by enzyme-linked immunosorbent assay (ELISA) and the cGMP/BNP ratio is calculated to determine cardiac natriuretic peptide resistance. Liquid chromatograph tandem mass spectrometry (LC-MS) based untargeted metabolomics analysis was applied to screen metabolic changes. The cGMP/BNP ratio was markedly lower in HF patients than controls. The cGMP/BNP ratio and ejection fraction (EF) were strongly correlated (R2 = 0.676, P < 0.05 ). Importantly, metabolic profiles were substantially different between HF patients and healthy controls. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis demonstrated that the differentially expressed metabolites are involved in signaling pathways that regulate cardiac functions. In HF patients, BNP resistance develops in association with a reduction in heart function and metabolic remodeling. It suggests possible functional roles of BNP resistance in the regulation of cardiac metabolism.

A novel structural composite (Fe-N/FeS@C) was synthesized via a self-doping strategy by the pyrolysis of a solid mixture of lignosulfonate and ferric nitrate pretreated by mechanical activation. The as-synthesized composite contained 7.5 wt% of single atomic iron moieties and 16.0 wt% of encapsulated FeS nanoparticles, with a high surface area of 1095.81 m2 g–1 and plentiful micropores and mesopores (0.4–10 nm). The Fe-N/FeS@C composite was confirmed to possess outstanding catalytic activity for sulfite activation in the degradation of methylene blue, with a high reaction rate constant (0.77 g g–1 min–1) and long cycling stability (83.1% of initial activity retention after 10 recycles). Moreover, the composite exhibited satisfactory activity recovery via a simple rinsing process with ethanol and HCl, and performed well in a wide pH range of 3–11. Density functional theory calculation results further demonstrated that the reaction energy of the rate-determining step, in which SO3•− was produced from SO32– on atomic Fe moieties, was lower than that of the formation of FeSO3+ by Fe3+ and SO32–. The excellent performance of Fe-N/FeS@C was mainly attributed to the combination of the high mass loading of active sites of atomic Fe moieties anchored into carbon matrix with encapsulated FeS nanoparticles. This study provides new insight into the development of environment-friendly, stable and atomic dispersion iron composite for sulfite activation to efficiently remove organic pollutants.

The present study focused on investigating the catalytic mechanism of metal salts (sodium hypophosphite, sodium bisulfate and ammonium ferric sulfate) for esterification of bagasse cellulose carried out by mechanical activation-assisted solid phase reaction in a stirring ball mill. FTIR analysis of the products confirmed that these metal salts could catalyze the esterification of cellulose. XRD, SEM, FTIR, and 31P-NMR analyses of different samples indicated a synergistic effect between metal salt and ball milling, and the presence of metal salts enhanced the destruction on crystal structure of cellulose by mechanical force. The catalytic mechanism of three metal salts was difference: sodium bisulfate and ammonium ferric sulfate belonged to the catalytic mechanism of protonic acid and Lewis acid, respectively, while the catalytic mechanism of sodium hypophosphite was considered as that it could react with maleic acid to form active intermediates under ball milling.

In order to learn about the esterification mechanism of lignin by mechanical activation-assisted solid-phase synthesis (MASPS) technology, lignin model compounds, p-hydroxy benzaldehyde (H), vanillin and vanillyl alcohol (G), and syringaldehyde (S), were used in the reaction with acetic anhydride, with 4-dimethyl amino pyridine (DMAP), sodium acetate, and sulfuric acid as catalysts. FTIR, NMR, and UV/vis analyses of the products showed that all of the catalysts could enhance the esterification. Both the phenolic hydroxyl and aliphatic hydroxyl participated in the esterification and the reactivity of the basic structural units of lignin had a descending order of H, G, and S. Oxidations could happen in the presence of unsaturated groups such as aldehyde in the lignin model compounds. The catalytic mechanism of the three kinds of catalyst was different, and the catalytic activity had a descending order of DMAP, sodium acetate, and sulfuric acid. The reactivity of phenolic hydroxyl was higher than that of aliphatic hydroxyl with DAMP as the catalyst, but the reactivity of aliphatic hydroxyl was higher than that of phenolic hydroxyl with sodium acetate or sulfuric acid as the catalyst. With sulfuric acid as the catalyst, some side reactions took place and resulted in the ring cleavage or cross-linking of the benzene ring. Consistency verification indicated that the use of lignin model compounds for studying the esterification mechanism of lignin was reasonable and feasible.

The purpose of the present study was to explore aging-associated cardiac dysfunction and the possible mechanism by which swimming exercise modulates cardiac dysfunction in aged mice. Aged mice were divided into two groups: i) Aged mice; and ii) aged mice subjected to swimming exercises. Another cohort of 4-month-old male mice served as the control group. Cardiac structure and function in mice were analyzed using hematoxylin and eosin staining, and echocardiography. The levels of oxidative stress were determined by measuring the levels of superoxide dismutase, malondialdehyde and reactive oxygen species (ROS). Levels of the endoplasmic reticulum (ER) stress-related protein PKR-like ER kinase, glucose-regulated protein 78 and C/EBP homologous protein were determined to evaluate the level of ER stress. The aged group exhibited an abnormal cardiac structure and decreased cardiac function, both of which were ameliorated by swimming exercise. The hearts of the aged mice exhibited pronounced oxidative and ER stress, which were ameliorated by exercise, and was accompanied by the reactivation of myocardial cGMP and suppression of cGMP-specific phosphodiesterase type 5 (PDE5). The inhibition of PDE5 attenuated age-induced cardiac dysfunction, blocked ROS production and suppressed ER stress. An ER stress inducer abolished the beneficial effects of the swimming exercise on cardiac function and increased ROS production. The present study suggested that exercise restored cardiac function in mice with age-induced cardiac dysfunction by inhibiting oxidative stress and ER stress, and increasing cGMP-protein kinase G signaling.

Ozone pollution control has become the focus of air pollution control at this stage and even during the 14th Five Year Plan period, so it is more and more important to measure ozone concentration precisely. In this paper, based on the measurement principle of ozone concentration by ultraviolet photometry, the ozone has characteristic absorption of ultraviolet light at 254 nm wavelength, according to Lambert-Biel's law, ozone concentration can be obtained by detecting the change of UV intensity. At the same time a new design of double optical cells and dual detectors is proposed, there is no fluctuation with one source, fast response time under alternating sampling, and the built-in ozone generator is used to achieve multi-point calibration, The test was made according the standard “HJ654-2013”, the test results are far better than the requirements in the standard.

Cellulose succinate, which was used for efficient adsorption of heavy metals, was directly prepared by mechanical activation (MA)-assisted solid-phase synthesis in a stirring ball mill with bagasse pulp and succinic acid as materials without the use of organic co-reagents and solvents. FTIR, XRD, SEM, and specific surface area analysis were used to characterize the structural characteristics of cellulose succinate. Furthermore, the effects of different degrees of esterification of modified cellulose on the adsorption of Cd2+ and Pb2+ were investigated. A surface charge characteristic was used to prove the effect of pH on the adsorption ability of cellulose succinate. It was found that the adsorption kinetics of Cd2+ and Pb2+ onto cellulose succinate fitted well with the pseudo-second-order model. The adsorption of Cd2+ and Pb2+ onto cellulose succinate was well described by the monolayer adsorption of the Langmuir isotherm model rather than the multilayer adsorption of the Freundlich isotherm model. The E values for the adsorption of Cd2+ and Pb2+ by cellulose succinate calculated by the Dubinin–Radushkevich equation were all in the range of 8–16 kJ mol−1, suggesting that the adsorption process mainly proceeded by ion exchange. The MA-assisted solid-phase synthesis method can produce efficient and environmental-friendly adsorbents.

A series of solid ternary lanthanide complexes with the general formula Ln(BA)3(PIP) (Ln = La–Lu, except Pm) were prepared with hydrated lanthanide chloride, benzoic acid (BA), and 2-phenylimidazo[4,5-f]1,10-phenanthroline (PIP). These obtained complexes were characterized by means of elemental analysis, EDTA volumetric analysis, IR spectroscopy, X-ray powder diffraction, and mass spectroscopy. The thermal decomposition mechanism of all complexes in the solid state was explored using TG–DTG techniques under dynamic flow of air atmosphere. Moreover, the constant-volume combustion energies, ∆c U, of the complexes were determined by a precise rotating-bomb calorimeter (RBC-type II) at 298.15 K. Their standard molar enthalpies of combustion, $$ \Delta _{\text{c}} H_{\text{m}}^{\uptheta} $$ , and standard molar enthalpies of formation, $$ \Delta_{\text{f}} H_{\text{m}}^{\uptheta} $$ , were calculated.

An approach for re-folding denatured proteins during proteome research by protein folding liquid chromatography (PFLC) is presented. Standard protein, α-chymotrypsin (α-Chy), was selected as a model protein and hydrophobic interaction chromatography was performed as a typical PFLC; the three different α-Chy states – urea-denatured (U state), its folded intermediates (M state) and nature state (N state) – were studied during protein folding. Based on the test by matrix-assisted laser desorption/ionization time of flight mass spectrometry and bioactivity, only one stable M state of the α-Chy was identified and then it was prepared for further investigation. The specific bioactivity of the refolded α-Chy was found to be higher than that of commercial α-Chy as the urea concentration in the sample solution ranged from 1.0 to 3.0 m; the highest specific bioactivity at urea concentration was 1.0 m, indicating the possibility for re-folding some proteins that have partially or completely lost their bioactivity, as a dilute urea solution was employed for dissolving the sample. The experiment showed that the peak height of its M state increased with increasing urea concentration, and correspondingly decreased in the amount of the refolded α-Chy. When the urea concentration reached 6.0 m, the unfolded α-Chy could not be refolded at all. Copyright © 2012 John Wiley & Sons, Ltd.

Cyanobacteria after outbreak and being randomly distributed produced microcystins,polycyclic aromatic hydrocarbons,harmful gases and other toxic substances.In this paper,the process of cyanobacteria decaying was simulated in laboratory,and the changes of organic elements,chloroform extracts A,saturated hydrocarbons and aromatic hydrocarbon during decaying of cyanobacteria had been surveyed.On this basis,we discussed the countermeasure of aromatic hydrocarbons and other toxic substances produced from the accumulation cyanobacteria.Results showed that after 1-month aerobic and 1-month anaerobic decaying,the contents of total aromatics and polycyclic aromatic hydrocarbons in cyanobacteria were decreased to the lowest.Besides,the anaerobic treatment increased the content of total aromatics slightly.The longer the action time of aerobic,the higher content of saturated hydrocarbons,and to the highest in cyanobacteria after 3-month aerobic decaying.N-alkanes will occur relatively strong C-C bond cleavage process,mainly generated small molecules gaseous hydrocarbons.Therefore,we argued that the cyanobacteria,which after 1-month aerobic and 1-month anaerobic decaying,was more suitable for organic fertilizer resource utilization in a pool,then the gas collected for combustion;the cyanobacteria after 3-month aerobic decaying was more suitable for bio-energy.Accordingly,we proposed that monitoring the humification process and to control the formation of harmful ingredients relying on the fluorescence intensity of phycobiliprotein and chlorophyll.

The effects of Hydrilla verticillata on water and sediment in eutrophic lake were investigated by a microcosm experiment. The experiment was conducted with lake water, sediment and H. verticillata collected from Yuehu Lake in Wuhan, China, in 1m x 1m x 1 in outdoor aquaria. The apical shoots of this species were planted at 4 densities (0, 50, 100 and 150 shoots/m(2)). Dissolved oxygen (DO), pH, total nitrogen (TN), ammonia (NH4+) and total phosphorus (TP) in water column were measured at the 1st, 8th, 21st, 38th and 55th day after initiation of the experiment, respectively, Eh, pH, TN and TP of sediment were measured as well. At the end of the duration, the plants were harvested and the dry biomasses were measured. The experimental results showed that the dry biomasses were 52.9, 31.9 and 24.8 times higher at harvest than that at the initiation of the experiment respectively. DO in water column of the treatments with plants was 2.6 times higher than that of the control, pH values also significantly increased up to 9.85 in the density of 150/m(2) at the 38th day. However, the 3 planting densities did not show significant difference in these two parameters. The concentrations of TN and NH4+ in water column with plants deceased by 90.2% and 70.0% compared with the control respectively, whereas, the differences among the treatments were not significant. TP in water column decreased with planting densities by 38.9%-57.1%, and the differences among treatments were distinct. As a function of radial oxygen releases from root, the Eh values of sediment increased by 58.6-109.4mV with the planting density compared with the control. Whereas, the pH in the 3 treatments decreased sharply during the first 20 days, then increased up to 7.20-7.34, but still lower than that of the control, which could be explained by the releases of root exudates. In addition, the growth of H. verticillata can effectively reduce the TN and TP in the sediment. It is concluded that the existence of H. verticillata can remove nutrition and improve the quality of water column and sediment. However, plant density is a factor need to be considered in revegetation of degraded lakes, because excessive density may inhibit the growth of plants. So harvesting at appropriate time is a necessary measure to enhance the effect of the submerged macrophyte.

The objective of this study was to optimize and characterize a novel polymeric mixed micelle composed of Pluronic P123 and F127 loaded with paclitaxel (PTX). A Doehlert matrix design was utilized to investigate the effect of four variables, namely P123 mass fraction, amount of water, feeding of PTX and hydration temperature on the responses including drug-loading coefficient (DL %), encapsulation ratio (ER %) and the percentage of PTX precipitated from the drug-loaded mixed micelles after 48 h at 37 (PTX precipitated %) for improvement of drug solubilization efficiency and micelle stability. PTX-loaded P123/F127 mixed micelles were prepared by thin-film hydration method. The optimized formulation showed a particle size of about 25 nm with ER %90%, and a sustained release behavior compared to Taxol. Micelle formation was confirmed by NMR spectroscopy. The mixed micelles had a low CMC of 0.0059% in water. In addition, micelle stability studies implied that introduction of Pluronic F127 (33 wt%) into P123 micelle system significantly increased the stability of PTX-loaded micelles. More importantly, in vitro cytotoxicity was assessed using human lung adenocarcinoma cell lines SPC-A1 and A-549 and was compared to Taxol and the free drug. The cell viability assay against A-549 cells exhibited the 50% inhibition concentration (IC50) of PTX-loaded P123/F127 mixed micelles (0.1 microg/ml) was much lower than those of Taxol injection (0.4 microg/ml) and the free PTX (1.7 microg/ml). Therefore, PTX-loaded P123/F127 mixed micelles may be considered as an effective anticancer drug delivery system for cancer chemotherapy.

The copper(II) complex of 6-benzylaminopurine (6-BAP) has been prepared with dihydrated cupric chloride and 6-benzylaminopurine. Infrared spectrum and thermal stabilities of the solid complex have been discussed. The constant-volume combustion energy, ΔcU, has been determined as −12566.92±6.44 kJ mol−1 by a precise rotating-bomb calorimeter at 298.15 K. From the results and other auxiliary quantities, the standard molar enthalpy of combustion, ΔcHmθ, and the standard molar of formation of the complex, ΔfHmθ, were calculated as −12558.24±6.44 and −842.50±6.47 kJ mol−1, respectively.

Fourteen rare earth complexes with salicylic acid RE(HSal)3·nH2O (HSal = C7H5O3; RE = La–Sm, n = 2; RE = Eu–Lu, n = 1) were synthesized and characterized by elemental analysis, and their thermal decomposition mechanism were studied with TG–DTG technology. The constant-volume combustion energies of complexes, ΔcU, were determined by a precise rotating-bomb calorimeter at 298.15 K. Their standard molar enthalpies of combustion, Δ c H m ∘ , and standard molar enthalpies of formation, Δ f H m ° , were calculated.

We have identified a new β chain hemoglobin (Hb) variant in a Chinese individual. Sequencing of the β-globin gene revealed a mutation in exon 2 at nucleotide 271, which results in the replacement of a glutamic acid by glutamine at codon 90 [β90(F6)Glu → Gln; GAG > CAG; HBB: c.271G > C] that we have named Hb Henan.

For the first time, methyl violet (MV) was used to determine nucleic acids with a resonance light scattering (RLS) technique. The interactions of MV with nucleic acids give strong signals of RLS at 327.0, 490.0 and 651.0 nm. Based on this reaction, a new quantitative determination method for nucleic acids in aqueous solutions has been developed. At pH 7.51 and ionic strength 0.005 mol kg−1, with 4.0×10−5 mol l−1 of MV, linear relationships were found between the enhanced intensity of RLS at 651.0 nm and the concentration of nucleic acids in the range 0–3.0 μlg ml−1 for herring sperm DNA (hsDNA) and calf thymus DNA (ctDNA), 0–4.0 μlg ml−1for yeast RNA (yRNA). The limits of detection were 404.5 ng ml−1 for herring sperm DNA, 764.0 ng ml−1 for calf thymus DNA and 414.9 ng ml−1 for yeast RNA. The assay is proved to be convenient, rapid, inexpensive and simple.

Characteristics of leaf essential oil extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS) from wild and domestication Chimonanthus praecox from Wanyuan City of Sichuan, China, were investigated. Their leaves had twenty-two common essential oil components containing the mains bornyl acetate, caryophyllene oxide and (-)-spathulenol. Their oils were characterized by sesquiterpenes and monoterpenes, especially, the oxygenated. However, the wild plants possessed higher essential oil content and more abundant chemical components than the domestication variety “Suxinmei”. The wild plants possessed sixty-four special components such as o-cymene, eucalyptol, γ-terpinene, linalool, etc, and most of them have enjoyable flavor and curative effect. But, “Suxinmei” was only with the three special components α-muurolene, γ-elemene and γ-himachalene, and without aromatic compounds. These results suggested that partial genetic materials controlling some especial nature products might have been changed or lost in the processes of evolution and domestication from wild to cultivar. It is of importance to powerfully protect and rationally utilize wild C. praecox germplasm resources. Key words: Chimonanthus praecox, germplasm resources, leaf, hydrodistillation, GC-MS, essential oil, yield, chemical component.