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Organic ligands are commonly believed to decrease the toxicity of metal ions, but there is few experimental evidence, especially for chromium (Cr(III)), which often coexists with organic compounds in industrial effluents. Here, the complexation of Cr(III) with acetate, lactate, l-tartrate, biphthalate and oxalate was tested under the conditions of a toxicity test, with high ion strength, by spectroscopic techniques. The stability constants of the complexes were found to follow the order Cr(III) oxalate > Cr(III) lactate > Cr(III) biphthalate > Cr(III) L-tartrate > Cr(III) acetate. Then, aquatic toxicity of Cr(III) to Photobacterium phosphoreum for a 15-min exposure period was tested in the absence and presence of organic ligands. Results unexpectedly show that the complexation of Cr(III) with acetic, lactate, l-tartrate and biphthalate resulted in enhanced toxicity to luminescent bacteria, whereas the coordination of Cr(III) with oxalate sharply alleviated the toxicity of individual oxalate and inorganic Cr(III), which was further confirmed by the scanning electron microscopy (SEM). Our findings show thus that organics do not always mitigate the toxicity of Cr(III) in acidic water.

Hyperhomocysteinemia (Hhcy) is an independent risk factor for Alzheimer’s disease (AD), and insulin-resistance is commonly seen in patients with Hhcy. Liraglutide (Lir), a glucagon-like peptide that increases the secretion and sensitivity of insulin, has a neurotrophic or neuroprotective effect. However, it is not known whether Lir ameliorates the AD-like pathology and memory deficit induced by Hhcy. By vena caudalis injection of homocysteine to produce the Hhcy model in rats, we found here that simultaneous administration of Lir for 2 weeks ameliorated the Hhcy-induced memory deficit, along with increased density of dendritic spines and up-regulation of synaptic proteins. Lir also attenuated the Hhcy-induced tau hyperphosphorylation and Aβ overproduction, and the molecular mechanisms involved the restoration of protein phosphatase-2A activity and inhibition of β- and γ-secretases. Phosphorylated insulin receptor substrate-1 also decreased after treatment with Lir. Our data reveal that Lir improves the Hhcy-induced AD-like spatial memory deficit and the mechanisms involve the modulation of insulin-resistance and the pathways generating abnormal tau and Aβ.

Florfenicol is widely used to control respiratory diseases and intestinal infections in food animals. However, there are increasing reports about florfenicol resistance of various clinical pathogens. floR is a key resistance gene that mediates resistance to florfenicol and could spread among different bacteria. Here, we investigated the prevalence of floR in 430 Pseudomonas aeruginosa isolates from human clinical samples and identified three types of floR genes (designated floR, floR-T1 and floR-T2) in these isolates, with floR-T1 the most prevalent (5.3%, 23/430). FloR-T2 was a novel floR variant identified in this study, and exhibited less identity with other FloR proteins than FloRv. Moreover, floR-T1 and floR-T2 identified in P. aeruginosa strain TL1285 were functionally active and located on multi-drug resistance region of a novel incomplete Tn4371-like integrative and conjugative elements (ICE) in the chromosome. The expression of the two floR variants could be induced by florfenicol or chloramphenicol. These results indicated that the two floR variants played an essential role in the host’s resistance to amphenicol and the spreading of these floR variants might be related with the Tn4371 family ICE.

Background: This work aimed to investigate the resistance mechanism to antimicrobial agents (especially florfenicol) exhibited by Providencia isolates obtained from various sources.Methods: The polymerase chain reaction (PCR) was performed to detect the distribution of the florfenicol resistance genes. Conjugation, S1-PFGE (S1 nuclease pulsed-field gel electrophoresis), sequencing and other molecular methods were employed to analyze the transferability and structure of the resistance gene-encoding plasmids. Results: It showed that the human pathogens exhibited a wider resistance spectrum, while the animal bacteria had higher MIC values for most antibiotics analyzed. Of the seven florfenicol resistance genes (floR, fexA, fexB, optrA, estDL136, cfr and pexA) screened, only floR was identified in both animal (5/10, 50%) and human bacteria (3/13, 23.1%), and none of them was detected in freshwater fish isolates (0/22). The floR-positive strains exhibited high MIC levels for florfenicol (≥ 64 mg/L). The whole genome sequencing of the multidrug-resistant Providencia rettgeri strain R39 demonstrated that it carried four plasmids, with two larger plasmids encoding 5 copies of the floR genes. The largest plasmid, pR39-33 (32,936 bp) with 4 floR genes, was composed of 4 copies of the second large plasmid pR39-8 which encoded 8 ORFs (open reading frames) including a floR and two mobilization genes (mobAC) in the form of tandem repeat. It indicated that the floR gene represented the primary mechanism underlying the florfenicol resistance of the Providencia isolates. Conclusions: This report is the first to describe an antibiotic-resistant plasmid composed of four copies of another plasmid sequence in the form of a tandem repeat.

Impaired wound healing often brings a set of problems in clinical practice. This study aimed to observe the wound healing potential of bovine bone collagen oligopeptides (BCOP) in mice. After an operation, mice in BCOP-treated groups were given intragastric administration of BCOP, while others were administered vehicle. Mice were sacrificed at different points. The wound healing condition and the tensile strength were observed, serum biochemical indexes and mRNA expression of level of related genes were measured. Compared with the normal control group, albumin (ALB), prealbumin (PA), transferrin (TRF), hydroxyproline (Hyp) levels and tension strength in the BCOP-treated groups increased significantly (p < 0.05). A pathological report showed that neutrophil granulocyte in the BCOP-treated groups decreased, while blood capillary and fibroblasts increased. The levels of serum inflammation indexes like interleukin (IL)-8, tumor necrosis factor (TNF)-α, chemokine (C-C motif) ligand 2 (CCL2) and C-reactive protein (CRP) significantly decreased in full-thickness incision model, whereas increased in full-thickness excision model (p < 0.05). Furthermore, IL-10, stromal cell-derived factor-1 alpha (SDF-1α) levels and the mRNA expression of vascular endothelial growth factor (VEGF) significantly increased in both models (p < 0.05). These results suggested that oral administration of BCOP could promote wound healing in mice.

The kinetics and mechanisms of the oxidation of Cr(III) in soil contaminated by unsaturated oils were investigated. Batch experiments were performed with unsaturated oils, namely, fish oil, hydrogenated lard oil, rapeseed oil, and caster oil. Impacts of environmental parameters, including temperature, soil pH, UV irradiation, oil content, and soil moisture content were examined. Results showed that oxidation of Cr(III) in oil-treated soils was accompanied by the formation of Cr(VI), which first increased and then decreased. Changes in the peroxide values of oils and the production of hexanal in the soil indicated that hydroperoxide was closely related to the formation of Cr(VI). tert-Butylhydroperoxide, as a model molecule of hydroperoxide, significantly enhanced the oxidation of Cr(III) in water. This result further showed that hydroperoxides were responsible for the oxidation of Cr(III). Native soil substances, such as organic matter, Fe(II), and microbes, and the decomposition products of hydroperoxides, such as aldehydes, could reduce Cr(VI). The change in Cr(VI) content in the soil resulted from the competition between the oxidation of Cr(III) and the reduction of Cr(VI). High temperature, high soil pH, UV irradiation, and low soil moisture content could facilitate the oxidation of Cr(III), which is of environmental significance.

BackgroundWith the wide use of florfenicol to prevent and treat the bacterial infection of domestic animals, the emergence of the florfenicol resistance bacteria is increasingly serious. It is very important to elucidate the molecular mechanism of the bacteria’s resistance to florfenicol.MethodsThe minimum inhibitory concentration (MIC) levels were determined by the agar dilution method, and polymerase chain reaction was conducted to analyze the distribution of florfenicol resistance genes in 39 CoNS strains isolated from poultry and livestock animals and seafood. The whole genome sequence of one multidrug resistant strain,Staphylococcus lentusH29, was characterized, and comparative genomics analysis of the resistance gene-related sequences was also performed.ResultsAs a result, the isolates from the animals showed a higher resistance rate (23/28, 82.1%) and much higher MIC levels to florfenicol than those from seafood. Twenty-seven animal isolates carried 37 florfenicol resistance genes (including 26fexA, 6cfrand 5fexBgenes) with one carrying acfrgene, 16 each harboring afexAgene, 5 with both afexAgene and afexBgene and the other 5 with both afexAgene and acfrgene. On the other hand, all 11 isolates from seafood were sensitive to florfenicol, and only 3 carried afexAgene each. The whole genome sequence ofS. lentusH29 was composed of a chromosome and two plasmids (pH29-46, pH29-26) and harbored 11 resistance genes, including 6 genes [cfr, fexA, ant(6)-Ia,aacA-aphD, mecAandmph(C)] encoded on the chromosome, 4 genes [cfr, fexA, aacA-aphDandtcaA] on pH29-46 and 1 gene (fosD) on pH29-26. We found that theS. lentusH29 genome carried two identical copies of the gene arrays ofradC-tnpABC-hp-fexA(5671 bp) and IS256-cfr(2690 bp), of which one copy of the two gene arrays was encoded on plasmid pH29-46, while the other was encoded on the chromosome.ConclusionsThe current study revealed the wide distribution of florfenicol resistance genes (cfr, fexAandfexB) in animal bacteria, and to the best of our knowledge, this is the first report that oneS. lentusstrain carried two identical copies of florfenicol resistance-related gene arrays.

Yokenella regensburgei, a member of the family Enterobacteriaceae, is usually isolated from environmental samples and generally resistant to early generations of cephalosporins. To characterize the resistance mechanism of Y. regensburgei strain W13 isolated from the sewage of an animal farm, whole genome sequencing, comparative genomics analysis and molecular cloning were performed. The results showed that a novel chromosomally encoded class C β-lactamase gene with the ability to confer resistance to β-lactam antibiotics, designated bla YOC - 1, was identified in the genome of Y. regensburgei W13. Kinetic analysis revealed that the β-lactamase YOC-1 has a broad spectrum of substrates, including penicillins, cefazolin, cefoxitin and cefotaxime. The two functionally characterized β-lactamases with the highest amino acid identities to YOC-1 were CDA-1 (71.69%) and CMY-2 (70.65%). The genetic context of the bla YOC - 1 -ampR-encoding region was unique compared with the sequences in the NCBI nucleotide database. The plasmid pRYW13-125 of Y. regensburgei W13 harbored 11 resistance genes (bla OXA - 10, bla LAP - 2, dfrA14, tetA, tetR, cmlA5, floR, sul2, ant(3″)-IIa, arr-2 and qnrS1) within an ∼34 kb multidrug resistance region; these genes were all related to mobile genetic elements. The multidrug resistance region of pYRW13-125 shared the highest identities with those of two plasmids from clinical Klebsiella pneumoniae isolates, indicating the possibility of horizontal transfer of these resistance genes between bacteria of various origins.

Background The molecular alterations underlying the pathogenesis of depression have not been systematically defined. Increasing evidence suggests that hippocampus metabolism is strongly involved in the pathogenesis of chronic mild unpredictable stress (CUMS)-induced depression. The principal objective of this study was to reveal important information concerning the pathogenesis of depression through a comprehensive analysis of metabolites in the hippocampus in a CUMS rat model. Methods Metabolites related to metabolic changes in the hippocampus in the CUMS model were collected from a depression-specific database and published literature. Potential metabolite pathways were identified by the Omicsolution tool. Then, crosstalk analysis was carried out to investigate the relationship between different important pathways. In addition, MetaboAnalyst was used to analyze potential metabolites for drug-related metabolite enrichment analysis, which was used to study hippocampus metabolite-related drug pathways in a CUMS model. Then, a metabolite-protein interaction (MPI) network was constructed and analyzed to identify important metabolites and proteins. The functional modules were extracted using the CNM network decomposition algorithm. Finally, neurotransmitters in the hippocampus of rats with CUMS depression were detected to verify the important pathways. Results In the current study, 53 significantly enriched pathways related to the 107 identified metabolites were selected, and the top ranked enriched pathways included arginine and proline metabolism, neuroactive ligand-receptor interaction, phenylalanine metabolism, bile secretion, and glutathione metabolism. Pathway crosstalk analysis showed that the significantly enriched pathways were divided into two interrelated modules, which were mainly involved in metabolism, signal transduction, neurotransmitters, and the endocrine system. Enrichment analysis of drug-related metabolic KEGG pathways identified the antibiotic pathways as the most important pathways. In the MPI network, the hub metabolites were phosphate, arachidonic acid, oxoglutaric acid, l -glutamic acid, and glutathione, and the hub proteins were Got1, Got2, Tat, Ccbl1, Ccbl2, Il4i1. A total of 16 functional modules were extracted from the MPI network by using the CNM algorithm. Finally, metabolites related to serotonergic synapses, dopaminergic synapses, and glutamatergic synapses were found to be involved in the pathology of depression. Conclusion We found that neurotransmitter pathways (serotonergic synapses, dopaminergic synapses and glutamatergic synapses) in the hippocampus play a crucial role in the underlying molecular mechanism of depression, which provides useful clues for identifying the detailed depression-associated metabolic profiles.

Depression is one of the most prevalent and serious mental disorders with a worldwide significant health burden. Metabolic abnormalities and disorders in patients with depression have attracted great research attention. Thirty-six metabolic biomarkers of clinical plasma metabolomics were detected by platform technologies, including gas chromatography–mass spectrometry (GC–MS), liquid chromatography–mass spectrometry (LC–MS) and proton nuclear magnetic resonance (1H-NMR), combined with multivariate data analysis techniques in previous work. The principal objective of this study was to provide valuable information for the pathogenesis of depression by comprehensive analysis of 36 metabolic biomarkers in the plasma of depressed patients. The relationship between biomarkers and enzymes were collected from the HMDB database. Then the metabolic biomarkers-enzymes interactions (MEI) network was performed and analyzed to identify hub metabolic biomarkers and enzymes. In addition, the docking score-weighted multiple pharmacology index (DSWMP) was used to assess the important pathways of hub metabolic biomarkers involved. Finally, validated these pathways by published literature. The results show that stearic acid, phytosphingosine, glycine, glutamine and phospholipids were important metabolic biomarkers. Hydrolase, transferase and acyltransferase involve the largest number of metabolic biomarkers. Nine metabolite targets (TP53, IL1B, TNF, PTEN, HLA-DRB1, MTOR, HRAS, INS and PIK3CA) of potential drug proteins for treating depression are widely involved in the nervous system, immune system and endocrine system. Seven important pathways, such as PI3K-Akt signaling pathway and mTOR signaling pathway, are closely related to the pathology mechanisms of depression. The application of important biomarkers and pathways in clinical practice may help to improve the diagnosis of depression and the evaluation of antidepressant effect, which provides important clues for the study of metabolic characteristics of depression.

Traditionally, SiC components with complex shapes are very difficult or even impossible to fabricate. This paper aims to develop a new manufacturing process, combining selective laser sintering (SLS), cold isostatic pressing (CIP) and polymer infiltration pyrolysis (PIP), to manufacture complex silicon carbide parts and improve the mechanical properties of silicon carbide ceramic parts. The density and porosity of SiC/SiC composites were measured. Furthermore, the mechanical properties of the specimens with cold isostatic pressing and the specimens without cold isostatic pressing were compared. The bending strength of the specimens with cold isostatic pressing was 201 MPa, and the elastic modulus was 1.27 GPa. And, the bending strength of the specimens without cold isostatic pressing was 142 MPa, and the elastic modulus was 0.88 GPa. Increasing the density of SiC/SiC can enhance the mechanical properties of SiC/SiC composites.

Background Florfenicol is a derivative of chloramphenicol that is used only for the treatment of animal diseases. A key resistance gene for florfenicol, floR, can spread among bacteria of the same and different species or genera through horizontal gene transfer. To analyze the potential transmission of resistance genes between animal and human pathogens, we investigated floR in Klebsiella pneumoniae isolates from patient samples. floR in human pathogens may originate from animal pathogens and would reflect the risk to human health of using antimicrobial agents in animals. Methods PCR was used to identify floR-positive strains. The floR genes were cloned, and the minimum inhibitory concentrations (MICs) were determined to assess the relative resistance levels of the genes and strains. Sequencing and comparative genomics methods were used to analyze floR gene-related sequence structure as well as the molecular mechanism of resistance dissemination. Results Of the strains evaluated, 20.42% (67/328) were resistant to florfenicol, and 86.96% (20/23) of the floR-positive strains demonstrated high resistance to florfenicol with MICs ≥512 μg/mL. Conjugation experiments showed that transferrable plasmids carried the floR gene in three isolates. Sequencing analysis of a plasmid approximately 125 kb in size (pKP18–125) indicated that the floR gene was flanked by multiple copies of mobile genetic elements. Comparative genomics analysis of a 9-kb transposon-like fragment of pKP18–125 showed that an approximately 2-kb sequence encoding lysR-floR-virD2 was conserved in the majority (79.01%, 83/105) of floR sequences collected from NCBI nucleotide database. Interestingly, the most similar sequence was a 7-kb fragment of plasmid pEC012 from an Escherichia coli strain isolated from a chicken. Conclusions Identified on a transferable plasmid in the human pathogen K. pneumoniae, the floR gene may be disseminated through horizontal gene transfer from animal pathogens. Studies on the molecular mechanism of resistance gene dissemination in different bacterial species of animal origin could provide useful information for preventing or controlling the spread of resistance between animal and human pathogens. Electronic supplementary material The online version of this article (10.1186/s13756-018-0415-0) contains supplementary material, which is available to authorized users.

Pyrolysis of heavy organic resources follows the radical mechanism. It involves the reactions between radicals generated from the cleavage of covalent bonds in a reactant and the reactions between the radicals and the reactant. The radicals are the reactive intermediates that govern the rate and product distribution of pyrolysis. This paper quantifies the reactive intermediate radicals generated in direct pyrolysis of two n -alkylbenzenes and the induced pyrolysis of the alkylbenzenes by the radicals, based on the data obtained in pyrolysis with and without tetralin that is able to donate hydrogen radicals. It is found that about 90% reactive intermediate radicals can be capped by the hydrogen radicals from tetralin. At 400–440 °C the contribution of induced pyrolysis is more than that of direct pyrolysis, about 1.9 times for n -propylbenzene and 3 times for n -pentylbenzene. The role of induced pyrolysis is larger at higher temperatures due to its higher activation energy than direct pyrolysis.

Intestinal injury and immune dysfunction are commonly encountered after irradiation therapy. While the curative abilities of ginseng root have been reported in prior studies, there is little known regarding its role in immunoregulation of intestinal repairability in cancer patients treated with irradiation. Our current study aims to closely examine the protective effects of ginseng-derived small molecule oligopeptides (Panax ginseng C. A. Mey.) (GOP) against irradiation-induced immune dysfunction and subsequent intestinal injury, using in vitro and in vivo models. Expectedly, irradiation treatment resulted in increased intestinal permeability along with mucosal injury in both Caco-2 cells and mice, probably due to disruption of the intestinal epithelial barrier, leading to high plasma lipopolysaccharide (LPS) and pro-inflammatory cytokines levels. However, when the cells were treated with GOP, this led to diminished concentration of plasma LPS and cytokines (IL-1 and TNF-α), suggesting its dampening effect on inflammatory and oxidative stress, and potential role in restoring normal baseline intestinal permeability. Moreover, the Caco-2 cells treated with GOP showed high trans-epithelial electrical resistance (TEER) and low FITC-dextran paracellular permeability when compared to the control group. This could be explained by the higher levels of tight junction proteins (ZO-1 and Occludin) expression along with reduced expression of the apoptosis-related proteins (Bax and Caspase-3) noticed in the GOP-treated cells, highlighting its role in preserving intestinal permeability, through prevention of their degradation while maintaining normal levels of expression. Further confirmatory in vivo data showed that GOP-treated mice exhibited high concentrations of lymphocytes (CD3+, CD4+, CD8+) in the intestine, to rescue the irradiation-induced damage and restore baseline intestinal integrity. Therefore, we propose that GOP can be used as an adjuvant therapy to attenuate irradiation-induced immune dysfunction and intestinal injury in cancer patients.

Bridged cycles are an important class of structural motif in various biologically active molecules. Rh(III)-catalyzed C–H activation of nitrones and azomethine imines in the context of dipolar addition with alkylidenecyclopropanes (ACPs) have been realized. By taking advantage of the ring strain in ACPs, the reaction with aryl nitrones delivered bridged [3.2.1] bicyclic isoxazolidines, and reaction with azomethine imines afforded bridged tricyclic pyrazolones under the same conditions, where both the nitrone and azomethine imine act as a dipolar directing group. All the reactions occurred under mild conditions with broad substrates scope, high efficiency, and >20:1 diastereoselectivity. The synthetic applications of this protocol have also been demonstrated.

The high hydrophilicity of cellulose nanocrystals (CNCs) greatly limits their application in the Pickering emulsion formulations. The work for the first time reports that a simple surface modification with octenyl succinic anhydride (OSA; food-grade) can remarkably improve the emulsification performance of CNCs, and facilitate the fabrication of the Pickering high-internal-phase-emulsions (HIPEs). The OSA modification occurred between the corresponding anhydride and the surface hydroxyl groups of CNCs, which remarkably increased their surface hydrophobicity. Stable and gel-like Pickering HIPEs with fine droplets could be easily fabricated using OSA-modified CNCs, even at very low particle concentrations in aqueous phase. The findings would be of crucial importance for greatly extending the applications of CNCs in emulsion formulations in the food and pharmaceutical fields.

Layered double hydroxide (LDH) films have been used to protect metal substrates because of their superior barrier performance and capability of capturing corrosive anions (such as Cl−) by exchange with interlayer anions. In this preliminary work, we determined that some photoactive LDHs (such as NiAl-LDH) can also provide cathodic protection to metals under light illumination, stemming from the light-generated electrons of semiconducting LDHs, if the energy level of the conduction band of LDHs is higher than the Fermi level of the metal. The current experimental results prove that the corrosion resistance of stainless steel is enhanced by the attached NiAl-LDH films in the dark and is further increased under light illumination due to photogenerated cathodic protection.

This work studies thermal reaction of a heavy oil at temperatures of 250–500 °C in sealed capillaries. The samples are extracted by chlorobenzene and toluene, and the insoluble matters are quantified in mass and in radical concentration. It is found that the chlorobenzene insolubles (CI) forms at temperatures of and higher than 440 °C while the toluene insolubles (TI) forms at temperatures higher than 350 °C. Both of these insoluble matters increase with time and temperature, and approach to similar asymptotic values. The CI formation can be fitted with a combination of the second-order and autocatalytic kinetics while the TI formation can be fitted with the second-order kinetics. Both CI and TI contain stable radicals measurable by electron spin resonance (ESR), and the radical concentration in CI is higher than that in TI. The kinetics of stable radical concentration in CI and TI are different from that in mass, except that of TI at a low temperature range (350–440 °C). The changes in ESR line width of CI and TI are also studied. The above data are also discussed in terms of hard coke (CI insoluble matters) and soft coke (the difference between TI and CI), and in activation energy.

Escherichia coli (E. coli) commonly reside in human intestine and most E. coli strains are harmless, but some serotypes cause serious food poisoning. This study identified and molecularly characterized blaSHV genes from 490 E. coli strains with multi-drug resistance in a hospital population. PCR and molecular cloning and southern blot were performed to assess functions and localizations of this resistant E. coli gene and the pulsed-field gel electrophoresis (PFGE) was utilized to demonstrate the clonal relatedness of the positive E. coli strains. The data showed that 4 of these 490 E. coli strains (4/499, 0.8%) carried blaSHV genes that included EC D2485 (blaSHV-5), EC D2487 (blaSHV-5), EC D2684 (blaSHV-11) and EC D2616 (blaSHV-195, a novel blaSHV). Analysis of blaSHV open-reading frame showed that blaSHV-5 had a high hydrolysis activity to the broad-spectrum penicillin (ampicillin or piperacillin), ceftazidime, ceftriaxone, cefotaxime and aztreonam. blaSHV-195 and blaSHV-11 had similar resistant characteristics with high hydrolysis activities to ampicillin and piperacillin, but low activities to cephalosporins. Moreover, the two blaSHV-5 genes were located on a transferable plasmid (23kb), whereas the other two blaSHV variants (blaSHV-11 and blaSHV-195) seemed to be located in the chromosomal material. Both EC D2485 and EC D2487 clones isolated in 2010 had the same DNA finger printing profile and they might be the siblings of clonal dissemination. The data from the current study suggest that the novel blaSHV and clonal dissemination may be developed, although blaSHV genes were infrequently identified in this hospital population. The results of the work demonstrate the necessity for molecular surveillance in tracking blaSHV-producing strains in large teaching hospital settings and emphasize the need for epidemiological monitoring.

A low-cost and water resistant biomass adhesive, collagen hydrolysate–silane coupling agent hybrids (CSH), was prepared by using collagen hydrolysate (CH) extracted from leather waste as the starting material, and silane coupling agent (SCA) as the crosslinking agent. The as-prepared adhesive was fully characterized by Fourier transform infrared spectroscopy (FTIR), 29Si CP-MAS NMR spectroscopy, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), ANS assay and ninhydrin assay. The as-prepared CSH exhibited pretty good adhesive strength and water resistance. Moreover, the water resistance of CSH can be conveniently tuned by changing the type and dosage of the silane coupling agent. When used as a wood adhesive, the dry adhesive strength of CSH was as high as 1.57 MPa, and the corresponding wet adhesive strength reached 0.95 MPa. Our experimental results suggest that the collagen hydrolysate extracted from leather waste has a great potential to be used as a low-cost and highly effective adhesive in the wood composite industry.

A porous amino resin melamine–formaldehyde (MF) with a high content of hydroxymethyl groups was prepared via the polycondensation of an excess of formaldehyde with melamine. Polyethylene imine (PEI) was then grafted onto the porous amino resin via a Mannich reaction between the active hydroxymethyl groups on the MF resin and the amino group on PEI to synthesize a solid amine adsorbent (MF-g-PEI). A large amount of hydroxymethyl groups were generated on the synthesized amino resin due to the excess formaldehyde used in the polycondensation reaction, which will provide abundant active sites to firmly combine with PEI and thus, enhance the stability of the MF-g-PEI adsorbent. The BET surface area and the pore volume of MF-g-PEI prepared using the optimal conditions were 460 m2 g−1 and 0.76 cm3 g−1, respectively. The CO2 adsorption capacity of MF-g-PEI, with a PEI loading of 11.35% can reach 1.32 mmol g−1 at 10 °C, while its amine utilization efficiency can reach up to 48.9%. The adsorbents also exhibited significantly improved adsorption kinetics and regeneration performance. This work provides a novel method that can achieve a promising solid amine adsorbent by directly grafting PEI onto porous material in the absence of an intermediate.

Protein N-glycosylation is ubiquitous in the brain and is closely related to cognition and memory. Alzheimer's disease (AD) is a multifactorial disorder that lacks a clear pathogenesis and treatment. Aberrant N-glycosylation has been suggested to be involved in AD pathology. However, the systematic variations in protein N-glycosylation and their roles in AD have not been thoroughly investigated due to technical challenges. Here, we applied multilayered N-glycoproteomics to quantify the global protein expression levels, N-glycosylation sites, N-glycans, and site-specific N-glycopeptides in AD (APP/PS1 transgenic) and wild-type mouse brains. The N-glycoproteomic landscape exhibited highly complex site-specific heterogeneity in AD mouse brains. The generally dysregulated N-glycosylation in AD, which involved proteins such as glutamate receptors as well as fucosylated and oligomannose glycans, were explored by quantitative analyses. Furthermore, functional studies revealed the crucial effects of N-glycosylation on proteins and neurons. Our work provides a systematic multilayered N-glycoproteomic strategy for AD and can be applied to diverse biological systems.

The genusCitrobacteris an opportunistic pathogen causing infections in animals, and the published data for its resistance to florfenicol are scarce. In this study, we investigated the antimicrobial susceptibility and molecular characteristics of florfenicol resistance genes amongCitrobacterisolates from animal and relevant environmental samples and conducted a comparative analysis of a multidrug-resistantCitrobacter freundiistrain isolated from a rabbit. Among 20Citrobacterstrains isolated from animal samples, resistance was most commonly observed to ampicillin (100%), tetracycline (75%), streptomycin (65%), florfenicol (60%), chloramphenicol (60%), and aztreonam (50%), while all the strains found in environmental samples were resistant to few antibiotics. The florfenicol resistance genefloRwas detected in 12 isolates (48%, 12/25) from animal samples, and all of thefloR-positive isolates were resistant to florfenicol with minimum inhibitory concentration (MIC) values ≥256 μg/mL. Sequencing and comparative analysis of the plasmids from a multidrug-resistantC. freundiiisolate named R47 showed that thefloR-containing region in the plasmid pR47-54 was a truncated transposon-like structure and could be found on both plasmids and chromosomes of bacteria of either animal or human origin. Furthermore, a range of antimicrobial and metal resistance genes associated with mobile genetic elements could be identified in pR47-54 and the other plasmid pR47-309 ofC. freundiiR47. These results provide in-depth views into the phenotypic and molecular characteristics ofCitrobacterisolates recovered from animal and relevant environmental samples, as well as highlight the role horizontal gene transfer plays in the dissemination of plasmid-encoded resistance genes.

For further applications of Alpiniae oxyphyllae fructus in modern clinical medicine, Alpiniae oxyphyllae fructus polysaccharide (AOFP) was studied in the present work. The extraction conditions of AOFP were optimized by the response surface method with a Box-Behnken design. The maximum extraction rate of AOFP was 3.18%. An anion-exchange DEAE-52 cellulose column and a Sephadex G-100 gel column were used to isolate the AOFP, and three polysaccharides (AOFP1, AOFP2, AOFP3) were obtained. All three polysaccharides possessed immunoregulatory activity, but the effects of AOFP1 were greater than the other two polysaccharides. AOFP1 significantly stimulated Th1- and Th2-type immune responses and specific immune responses. Meanwhile, the characterization of AOFP1 was studied. AOFP1 was composed of arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid at a molar ratio of 16.46:12.7:4.9:17.11:4.35:6.52:6 with an average molecular weight of 43.4 kDa. These results suggest that AOFP1 can be developed as a natural immunomodulatory drug.

Due to inappropriate use, florfenicol resistance is becoming increasingly serious among animal respiratory tract and gut bacteria. To detect the florfenicol resistance mechanism among Enterobacteriaceae bacteria, 292 isolates from animal feces were examined. The agar dilution method was conducted to determine the minimum inhibitory concentration (MIC) for florfenicol, and polymerase chain reaction (PCR) was performed to detect florfenicol resistance genes. To further explore the molecular mechanism of florfenicol resistance, the whole-genome Leclercia adecarboxylata R25 was sequenced. Of the strains tested, 61.6% (180/292) were resistant to florfenicol, 64.4% (188/292) were positive for floR, and 1.0% (3/292) for cfr. The whole-genome sequence analysis of L. adecarboxylata R25 revealed that the floR gene is carried by a transposon and located on a plasmid (pLA-64). Seven other resistance genes are also encoded on pLA-64, all of which were found to be related to mobile genetic elements. The sequences sharing the greatest similarities to pLA-64 are the plasmids p02085-tetA of Citrobacter freundii and p234 and p388, both from Enterobacter cloacae. The resistance gene-related mobile genetic elements also share homologous sequences from different species or genera of bacteria. These findings indicate that floR mainly contributes to the high rate of florfenicol resistance among Enterobacteriaceae. The resistance gene-related mobile genetic elements encoded by pLA-64 may be transferred among bacteria of different species or genera, resulting in resistance dissemination.

We report that the coupling of methane dehydroaromatization (MDA) and methanol methylation over a Mo/HZSM-5 catalyst can realize the direct conversion of methane to benzene, toluene, and xylene (BTX) with long-time steady state (60 h), higher activity (26.4%), and selectivity of BTX (>90%) at atmospheric pressure and 973 K. Based on characterization, it was confirmed that the formed benzene can be effectively methylated by methanol, leading to high activity and stability, which proves that the coke from polycondensation of the formed benzene results in rapid deactivation of MDA.

High lead solders have long been used for the assembly of underhood automotive thick-film hybrid modules. With the move to lead-free solders in the electronics industry, there is an increasing interest in alternatives to high lead solders in these applications. A AgBiX solder paste has been evaluated for SiC die and resistor attach for 200 °C applications in vehicles. Die attached to thick-film Ag metallized substrates showed no degradation in shear strength after 2000-h aging at 20 °C, while die attached to PdAg thick-film metallization exhibited a decrease in shear strength of $\sim 30$ %. After 2000-h aging at 200 °C, chip resistors showed a decrease in shear force at fracture of $\sim 44$ % and 60% for assembly on thick-film Ag and thick-film PdAg, respectively.

Ethnopharmacological relevance Zicao is the dried root of Lithospermum erythrorhizon Sieb, et Zucc, Arnebia euchroma (Royle) Johnst, or Arnebia guttata Bunge and commonly used to treat viral infection, inflammation, arthritis and cancer in China.Shikonin (SKN) is a major active chemical component isolated from zicao. Previous research showed that SKN has anti-inflammatory, immunomodulatory and analgesic effects, and inhibits the development of arthritis and the condition of collagen arthritis (CIA) mice; nevertheless, its role in the angiogenesis of rheumatoid arthritis (RA) has not been elucidated. Aim of the study The purpose of this study was to investigate the antiangiogenic activity of SKN in CIA rats and various angiogenesis models. Material and methods The anti-arthritic effect of SKN on CIA rats was tested by arthritis score, arthritis incidence, radiological observation and histopathology evaluation of inflamed joints. Vessel density evaluated with CD31 immunohistochemistry/immunofluorescence in joint synovial membrane tissues of CIA rats, chick chorioallantoic membrane assay, rat aortic ring assay, and the migration, invasion, adhesion and tube formation of human umbilical vein endothelial (HUVEC) cells induced by tumor necrosis factor (TNF)-α were used to measured the antiangiogenenic activity of SKN. Moreover, the effect of SKN on the expression of angiogenic mediators, such as vascular endothelial growth factor (VEGF), VEGFR2, TNF-α, interleukin (IL)-1β, platelet derived growth factor (PDGF) and transforming growth factor (TGF)-β in sera and joint synovia of rats, and in TNF-α-induced MH7A/HUVEC cells were measured by immunohistochemistry, enzyme linked immunosorbent assay, Western blot and/or real-time polymerase chain reaction (PCR). Through the analysis of protein and mRNA levels of phosphoinositide 3-kinase (PI3K), Akt and PTEN, and the autophosphorylation of ERK1/2, JNK and p38 in joint synovia of rats and in TNF-α-induced HUVEC cells, the molecular mechanism of its inhibition was elucidated by using Western blot and/or real-time PCR. Results SKN significantly reduced the arthritis score and arthritis incidence, and inhibited inflammation, pannus formation, cartilage and bone destruction of inflamed joints in CIA rats. Partially, SKN remarkably decreased the immature blood vessels in synovial membrane tissues of inflamed joints from CIA rats. It also suppressed in vivo angiogenesis in chick embryo and VEGF165-induced microvessel sprout formation ex vivo. Meanwhile, SKN inhibited TNF-α-induced migration, invasion, adhesion and tube formation of HUVEC cells. Moreover, SKN significantly decreased the expression of angiogenic activators including VEGF, VEGFR2, TNF-α, IL-1β, PDGF and TGF-β in synovia of CIA rats and/or in MH7A/HUVEC cells. More interestingly, SKN downregulated PI3K and Akt, and simultaneously upregulated PTEN both at protein and mRNA levels in synovia tissues and/or in TNF-α-induced HUVEC cells. It also suppressed the phosphorylation and gene level of TNF-α-induced signaling molecules, as ERK1/2, JNK, and p38 in synovium and/or in TNF-α-induced HUVEC cells. Conclusion These findings indicate for the first time that SKN has the anti-angiogenic effect in RA in vivo, ex vivo and in vitro by interrupting the PI3K/AKT and MAPKs signaling pathways.

We report that oil-in-water (o/w) high internal phase emulsions (HIPEs) can be ultra-efficiently stabilized by globular proteins in the presence of appropriate concentrations of polyols. Using bovine serum albumin (BSA) and trehalose as the model globular protein and polyol, stable HIPE gels at 0.8 oil volume fraction can be easily prepared at a protein concentration in the aqueous phase as low as 0.005 wt% in the presence of 40 wt% trehalose. Higher concentrations of polyols facilitated the formation of finer HIPEs with a stronger gel network associated with a higher extent of droplet bridging. The HIPE gels exhibited excellent coalescence stability against long-term storage or upon extensive heating. The ultra-efficient stabilization of BSA in the presence of trehalose arises from two contributions: facilitated formation of bridged emulsions and interfacial stabilization of trehalose aggregates. The soft particulate nature of BSA in the presence of trehalose was due to the formation of a core-shell nanostructure with trehalose molecules surrounding the protein core. The findings provide a novel and facile strategy to transform globular proteins into outstanding soft particles for stabilizing HIPEs, as well as guiding the development of novel biocompatible and even food-grade HIPEs with promising applications in the food, cosmetics and pharmaceutical fields.

The small size and low DNA amount of bacterial cells have hindered establishing phenome-genome links in a precisely indexed, one-cell-per-reaction manner. Here, Raman-Activated Gravity-driven single-cell Encapsulation and Sequencing (RAGE-Seq) is presented, where individual cells are phenotypically screened via single-cell Raman spectra (SCRS) in an aquatic, vitality-preserving environment, then the cell with targeted SCRS is precisely packaged in a picoliter microdroplet and readily exported in a precisely indexed, "one-cell-one-tube" manner. Such integration of microdroplet encapsulation to Raman-activated sorting ensures high-coverage one-cell genome sequencing or cultivation that is directly linked to metabolic phenotype. For clinical Escherichia coli isolates, genome assemblies derived from precisely one cell via RAGE-Seq consistently reach >95% coverage. Moreover, directly from a urine sample of urogenital tract infection, metabolic-activity-based antimicrobial susceptibility phenotypes and genome sequence of 99.5% coverage are obtained simultaneously from precisely one cell. This single-cell global mutation map corroborates resistance phenotype and genotype, and unveils epidemiological features with high specificity and sensitivity. The ability to profile and correlate bacterial metabolic phenome and high-quality genome sequences at one-cell resolution suggests broad application of RAGE-Seq.

This work was conducted to study the effect of soil pH (4.0, 6.0, and 8.0) on the transport, fractionation, and oxidation of trivalent chromium [Cr(III)]. Variation in pH altered soil chemical and mineralogical properties such as zeta potential, cation exchange capacity and redox potential of natural soil. Breakthrough curves and batch sorption experiments coupled with fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses demonstrated that the easy mobility of Cr(III) in pH 4.0 soil was dominated by the limited coordination effect. The high retention of Cr(III) in pH 8.0 soil was mainly ascribed to the hydrolysis. Incubation experiments indicated that the proportions of Cr in exchangeable fraction decreased with increasing of soil pH and incubation time, and kinetics analysis revealed that the time dependent transformation was controlled by mass transfer and chemical processes (e.g., hydrolysis, ion association). The XPS confirmed the oxidation of Cr(III) in pH 8.0 soil during the incubation period. Furthermore, the content of toxic hexavalent chromium [Cr(VI)] was positively associated with time and initial concentration of Cr(III) released. These results revealed the hazardousness of Cr(III) in soil contaminated simultaneously by inorganic acid and alkali.

To characterize the florfenicol resistance gene and analyze the structure of the resistance gene-related sequence of an Raoultella planticola strain S25 isolated from a duck fecal sample from a farm in South China. Molecular cloning was performed to clone the resistance genes such as mdfA, floR and so on, and the minimum inhibitory concentrations (MICs) were quantified to determine the resistance levels generated by the cloned genes and the related strains. Sequencing and comparative genomics methods were used to analyze the structure of the resistance gene-related sequence. The result showed that the genome of R. planticola S25 consists of a 5.47 Mb chromosome encoding 4962 predicted coding sequence (CDS) and a 68,566 bp plasmid, pS25-68, encoding 84 ORFs. The plasmid sharing the greatest sequence identity with the floR-carrying plasmid pS25-68 is plasmid1 in Klebsiella pneumoniae strain blaNDM-1, which was isolated from a patient in Canada. The mdfA1 gene encoded on the chromosome generated resistance to florfenicol in addition to chloramphenicol. Comparative genomic analysis of the floR-related transposon-like fragment of pS25-68 showed that an approximately 3 kb sequence encoding IS91-virD2-floR-lysR was conserved and presented in the majority of the sequences (84.5 %, 169/200) collected from the database. The results of this work demonstrated that horizontal transfer of the florfenicol resistance gene floR occurred widely between the bacteria of different species and with different origins and that additional florfenicol resistance genes may be present in the bacterial population.

Soy proteins have attracted fast increasing interests to be used in food emulsion formulations, due to their good emulsifying properties. Soy β-conglycinin (SC) and glycinin are the two major storage globulins in soy proteins, with the former generally recognized to exhibit much better emulsifying properties than the latter. The current work reported that the treatment of SC with ethanol at concentrations ([E]) of 20–80% (v/v) remarkably improved its emulsification performance and interfacial stabilization, in a [E]-dependent way. The influence of the ethanol treatment on the physicochemical and structural properties of SC was characterized. As expected, the treatment led to an [E]-dependent aggregation of SC, and formation of larger particles with more compact structure. Next, the emulsifying and interfacial properties of these ethanol-treated SC samples were evaluated in terms of emulsification performance and interfacial stabilization, at two oil volume fractions of 0.2 and 0.8. In both cases, the ethanol-treated SC showed greatly improved emulsification performance and interfacial stabilization. The improvements were largely due to the facilitated formation of bridged emulsions, via the strengthened Pickering stabilization by ethanol-induced aggregation. Even at a low concentration of 0.5 wt%, the ethanol-treated SC could still produce a kind of fine emulsions (produced by microfluidization), or high internal phase emulsions with a self-supporting gel network (that could resist the disruption of 6 M urea). The results demonstrated that the ethanol pretreatment can be applied as an effective modification to remarkably improve the emulsifying properties of SC, through the strengthening of its Pickering stabilization.

The pathophysiological mechanism of depression is complex and its etiology remains unclear. Metabolomics can be used to monitor multiple metabolic pathways simultaneously, thereby investigating the mechanisms of depression onset and its regulation. Therefore, we studied the metabolic profile of urine samples from a rat model of depression for identifying potential metabolic biomarkers associated with depression. The depression model of rats was induced by 14-d simulated microgravity (SMG) treatment. Principal component analysis and orthogonal partial least squares discriminate analysis were performed to classify and identify the differences of endogenous metabolites in urine between the normal and depressed rats. Multivariate statistical analysis revealed distinct separation between the urinary metabolic profiles of SMG-treated and control rats. Citric acid, oxalosuccinic acid, creatine, proline, cyclic AMP, L-dihydroxyphenylalanine (DOPA), phenylacetylglycine, 5-hydroxyindole acetaldehyde, succinylcholine, deoxyuridine, 3-hydroxyhippuric acid, glutamine, and 5-hydroxytryptophan levels were significantly reduced, whereas indole-3-acetaldehyde, xanthurenic acid, taurine, kynurenic acid, hippuric acid, 5-hydroxyindoleacetic acid, 2-phenylethanol glucuronide, 2-isopropyl-3-oxosuccinate, and adrenaline levels were elevated significantly in model group. These biochemical changes were related to tryptophan, arginine, proline, and phenylalanine metabolism, and perturbations in energy metabolism. These details of depression will be helpful to the clinical diagnosis of depression caused by space and gravity.

The antimicrobial resistance crisis makes it critically important for laboratories to closely monitor trends and mechanisms of emerging antimicrobial resistance in clinical isolates. Bacteroides fragilis is an anaerobic pathogen that causes several serious infections and is increasingly resistant to antimicrobial agents. However, data from China regarding antimicrobial resistance in B. fragilis are limited. In this work, the mechanism underlying carbapenem resistance in 44 B. fragilis isolates collected from a Chinese hospital was investigated. Antimicrobial susceptibility testing for 13 antimicrobial agents was performed by the agar dilution method, and the contribution of efflux pumps to carbapenem resistance was analysed. Genetic relatedness of the isolates was determined by PFGE. Outer membrane porins were analysed in isolates with reduced carbapenem susceptibility. Potential carbapenemase-encoding genes were identified, and the location and environment of the cfiA gene was analysed. Among the 44 isolates, 18.2%, 29.5%, 22.7%, 100%, 100%, 29.5%, 15.9%, 81.8%, 88.6% and 47.7% were resistant to imipenem, meropenem, ertapenem, penicillin, ampicillin, amoxicillin/clavulanic acid, piperacillin/tazobactam, clindamycin, tetracycline and moxifloxacin, respectively. None of the isolates were resistant to metronidazole, cefoxitin or chloramphenicol. A chromosomally located gene (cfiA) encoding a metallo-β-lactamase was identified in 16 isolates (36.4%). A conserved insertion sequence of IS1187 or IS613 was upstream of cfiA in eight isolates with high-level carbapenem resistance. The insertion sequences were associated with increased carbapenem resistance in B. fragilis by upregulating the expression of cfiA as shown by RT-qPCR. This is the first study to describe a mechanism of carbapenem resistance in B. fragilis in mainland China.

Impaired wound healing is a major clinical problem in patients with diabetes and is the leading cause of lower limb amputation. This study is aimed to observe the effects of small molecule oligopeptides isolated from sea cucumber (SCCOPs) on the wound healing process in diabetic mice. Ninety db/db male mice were divided into five groups, including the model control group, whey protein group (0.50 g/kg) and three SCCOPs dose groups (0.25 g/kg, 0.50 g/kg and 1.00 g/kg). Additionally, 18 db/m male mice were used as normal control group. After full-thickness incisions on the dorsum, mice in SCCOPs-treated groups were intragastrically administered SCCOPs, while others were administered vehicle or whey protein. Mice were sacrificed on days 4, 7 and 14. The wound healing condition, inflammatory response, angiogenesis, collagen deposition, oxidative stress and nutritional status were evaluated. A pathological report showed increased vascularisation, collagen deposition and epithelialisation in SCCOPs-treated groups. SCCOPs-treated mice showed decreased C-reactive protein (CRP), interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, chemokine (C-C motif) ligand 2 (CCL2) and reactive oxygen species (ROS) contents, and increased IL-10, stromal cell-derived factor-1 alpha (SDF-1α), nitric oxide (NO), albumin (ALB), prealbumin (PA) and transferrin (TRF) levels and vascular endothelial growth factor (VEGF) expression. All parameters were significant (p < 0.05) in comparison to model control group. These results suggest that treatment with SCCOPs can promote significant wound healing in diabetic mice.

Ring-opening copolymerization of aziridine in situ into substrates to introduce polyethyleneimine (PEI) not only required strict experimental conditions but employed the highly toxic monomer aziridine. In this paper, an effective and safe new procedure is developed for hyperbranched structure synthesis by stepwise growth using N-(2-chloroethyl)-benzaldimine as a monomer. Hyperbranched solid amine fibers for CO2 capture were prepared through co-irradiation grafting copolymerization of polypropylene fibers with glycidyl methacrylate, followed by amination with ethylenediamine, Hoffman alkylation with N-(2-chloroethyl)-benzaldimine and then hydrolysis to remove benzaldehyde groups. It was shown that the adsorption performance of the hyperbranched solid amine fibers G2.0 and G3.0 has been greatly improved compared with first generation G1.0 fibers, and the adsorption capacities of G2.0 and G3.0 were 5.35 mmol g−1 and 5.53 mmol g−1 at 30 °C, respectively. The amine utilization of G2.0 fibers could reach 84.1%. These results demonstrate that the branched structure can promote the adsorption capacity and efficiency greatly due to its low mass transfer resistance of CO2, which is more favorable than a linear amination reagent.

A new strategy for simultaneous detection of carcinoembryonic antigen and alpha-fetoprotein is introduced. In this work, an ionic liquid–reduced graphene oxide composite was combined with two different redox probes, thionine and ferricyanide, respectively, through electrostatic adsorption. The resulting nanocomposites were then attached to gold nanoparticles in order to supply a large, accessible surface for the immobilization of anti-carcinoembryonic antigen and anti-alpha-fetoprotein as immunosensing probes. A chitosan–AuNP modified glassy carbon electrode was used as a substrate to immobilize capture antibodies. As such, a sandwich-type electrochemical immunosensor for the simultaneous detection of carcinoembryonic antigen and alpha-fetoprotein was successfully developed. The electric potentials and voltammetric peaks measured using square wave voltammetry reflected the identity and concentrations of the corresponding antigen. Under optimized conditions, the immunosensor exhibited good sensitivity and selectivity with linear ranges of 0.05–100 ng mL−1, and detection limits for carcinoembryonic antigen and alpha-fetoprotein of 0.02 ng mL−1 and 0.01 ng mL−1 (S/N = 3), respectively. The reliability of the proposed immunosensor has been proven by the detection of carcinoembryonic antigen and alpha-fetoprotein in clinical serum samples and the results were in good agreement with a standard enzyme-linked immunosorbent assay.

Rh(III)-catalyzed synthesis of nitro-functionalized indenes has been realized via C-H activation of arylnitrones and annulation with nitroolefins. The reaction proceeded in moderate to high yields with good functional group tolerance under ambient atmosphere.

In this work, a sandwich-format electrochemical immunosensor has been fabricated in the aim of simultaneous detection of carcinoembryonic antigen (CEA) and alpha-fetoprotein (AFP) using metal ions tagged immunocolloidal gold nanocomposites as signal tags. The capture anti-CEA and anti-AFP were immobilized onto the chitosan-Au nanoparticles (CHIT-AuNPs) membrane modified glassy carbon electrode through glutaraldehyde (GA). The metal ion labels could be detected directly through differential pulse voltammetry (DPV) without metal pre-concentration, and the distinct voltammetric peaks had a close relationship with each sandwich-type immunoreaction. Under the optimized conditions, the multiplexed immunoassay exhibited good sensitivity and selectivity for the simultaneous determination of CEA and AFP with linear ranges of 0.01-50 ng mL(-1). The detection limits for CEA and AFP are 4.6 pg mL(-1) and 3.1 pg mL(-1), respectively. The method was successfully applied for the determination of AFP and CEA levels in clinical serum samples, and the results were in good agreement with standard enzyme linked immunosorbent assay (ELISA). This approach gives a promising simple and sensitive immunoassay strategy for clinical applications.

We report lyotropic smectic liquid crystalline phase behavior of silica nanorods dispersed in binary mixtures of dimethyl sulfoxide (DMSO) and water (H2O). The phase behavior is affected by nanorod size polydispersity and DMSO concentration in the binary solvent. The isotropic to biphasic transition is strongly affected by the relative amount of DMSO in the solvent, but the solvent has little effect on the biphasic to liquid crystal transition above 40/60 DMSO/H2O by volume. At less than 40% DMSO, increasing silica nanorod concentration initially results in the formation of liquid crystalline domains, but further increasing silica concentration results in crystal solvate formation. The morphology of the liquid crystalline phase is strongly affected by the size polydispersity, with lower polydispersity leading to a more uniform structure. As in other lyotropic nanocylinder systems, the microstructure of continuous solid films produced from the dispersions was affected by both the initial microstructure and the applied shear.

Most chemotherapeutical drugs kill cancer cells chiefly by inducing DNA damage, which unfortunately also causes undesirable injuries to normal tissues, mainly due to p53 activation. We report a novel strategy of normal tissue protection that involves p53/NF-κB coordinated metabolic regulation. Pretreatment of untransformed cells with low doses of arsenic induced concerted p53 suppression and NF-κB activation, which elicited a marked induction of glycolysis. Significantly, this metabolic shift provided cells effective protection against cytotoxic chemotherapy, coupling the metabolic pathway to cellular resistance. Using both in vitro and in vivo models, we demonstrated an absolute requirement of functional p53 in arsenic-mediated protection. Consistently, a brief arsenic pretreatment selectively protected only normal tissues, but not tumors, from toxicity of chemotherapy. An indispensable role of glycolysis in protecting normal tissues was demonstrated by using an inhibitor of glycolysis, 2-deoxyglucose, which almost totally abolished low-dose arsenic-mediated protection. Together, our work demonstrates that low-dose arsenic renders normal cells and tissues resistant to chemotherapy-induced toxicity by inducting glycolysis.

Anatase nano-TiO2 film was prepared by sol-gel method and graphene oxide nanosheets synthesized by Hummers method were deposited on this TiO2 thin film. Another nano-TiO2 film was then deposited on the graphene film forming sandwich-like to avoid graphene layer peeled off. Scanning electron microscope shows that TiO2 particles layer with a diameter of about 20 nm were densely and uniformly deposited on both surfaces of the graphene layer to form a sandwich-like composite structure. The composite films exhibit excellent photocatalytic degradation to methyl orange and remains chemically stable in the whole process without anything exfoliation.

C-type lectins play important roles in innate immunity of invertebrates. In the present study, we report a novel C-type lectin, named FcLec4, from the Chinese white shrimp Fenneropenaeus chinensis. FcLec4 contains a single carbohydrate recognition domain (CRD) with a putative signal peptide. Phylogenetic analysis indicated that FcLec4 was distant from most reported C-type lectins from shrimps. The expression of FcLec4 increased at both mRNA and protein level after stimulation of Vibrio anguillarum. Recombinant FcLec4 could agglutinate both Gram-positive and -negative bacteria in the presence of calcium. The recombinant protein could bind to peptidoglycan and selectively bind to microorganisms. Interestingly, the tight binding of recombinant FcLec4 to V. anguillarum might facilitate the subsequent clearance of the bacteria in vivo. To the best of our knowledge, this might be the first report that a C-type lectin was found to be directly involved in the anti-V. anguillarum response in shrimps.

Lectins are regarded as potential immune recognition proteins. In this study, a novel C-type lectin (Fc-Lec2) was cloned from the hepatopancreas of Chinese shrimp, Fenneropenaeus chinensis. The cDNA of Fc-Lec2 is 1219 bp with an open reading frame (ORF) of 1002 bp that encodes a protein of 333 amino acids. Fc-Lec2 contains a signal peptide and two different carbohydrate recognition domains (CRDs) arranged in tandem. The first CRD contains a QPD (Gln-Pro-Asp) motif that has a predicted binding specificity for galactose and the second CRD contains a EPN (Glu-Pro-Asn) motif for mannose. Fc-Lec2 was constitutively expressed in the hepatopancreas of normal shrimp, and its expression was up-regulated in the hepatopancreas of shrimp challenged with bacteria or viruses. Recombinant mature Fc-Lec2 and its two individual CRDs (CRD1 and 2) did not have hemagglutinating activity against animal red blood cells, but agglutinated some gram-positive and gram-negative bacteria in a calcium-dependent manner. The three recombinant proteins also bound to bacteria in the absence of calcium. Fc-Lec2 seems to have broader specificity and higher affinity for bacteria and polysaccharides (peptidoglycan, lipoteichoic acid and lipopolysaccharide) than each of the two individual CRDs. These data suggest that the two CRDs have synergistic effect, and the intact lectin may be more effective in response to bacterial infection, the Fc-Lec2 performs its pattern recognition function by binding to polysaccharides of pathogen cells.

Conductive and electroactive polymers have the potential to enhance engineered cardiac tissue function. In this study, an interpenetrating network of the electrically-conductive polymer polypyrrole (PPy) was grown within a matrix of flexible polycaprolactone (PCL) and evaluated as a platform for directing the formation of functional cardiac cell sheets. PCL films were either treated with sodium hydroxide to render them more hydrophilic and enhance cell adhesion or rendered electroactive with PPy grown via chemical polymerization yielding PPy–PCL that had a resistivity of 1.0 ± 0.4 kΩ cm, which is similar to native cardiac tissue. Both PCL and PPy–PCL films supported cardiomyocyte attachment; increasing the duration of PCL pre-treatment with NaOH resulted in higher numbers of adherent cardiomyocytes per unit area, generating cell densities which were more similar to those on PPy–PCL films (1568 ± 126 cells mm −2 , 2880 ± 439 cells mm −2 , 3623 ± 456 cells mm −2 for PCL with 0, 24, 48 h of NaOH pretreatment, respectively; 2434 ± 166 cells mm −2 for PPy–PCL). When cardiomyocytes were cultured on the electrically-conductive PPy–PCL, more cells were observed to have peripheral localization of the gap junction protein connexin-43 (Cx43) as compared to cells on NaOH-treated PCL (60.3 ± 4.3% vs. 46.6 ± 5.7%). Cx43 gene expression remained unchanged between materials. Importantly, the velocity of calcium wave propagation was faster and calcium transient duration was shorter for cardiomyocyte monolayers on PPy–PCL (1612 ± 143 μm/s, 910 ± 63 ms) relative to cells on PCL (1129 ± 247 μm/s, 1130 ± 20 ms). In summary, PPy–PCL has demonstrated suitability as an electrically-conductive substrate for culture of cardiomyocytes , yielding enhanced functional properties; results encourage further development of conductive substrates for use in differentiation of stem cell-derived cardiomyocytes and cardiac tissue engineering applications. Statement of Significance Current conductive materials for use in cardiac regeneration are limited by cytotoxicity or cost in implementation. In this manuscript, we demonstrate for the first time the application of a biocompatible, conductive polypyrrole–polycaprolactone film as a platform for culturing cardiomyocytes for cardiac regeneration. This study shows that the novel conductive film is capable of enhancing cell–cell communication through the formation of connexin-43, leading to higher velocities for calcium wave propagation and reduced calcium transient durations among cultured cardiomyocyte monolayers. Furthermore, it was demonstrated that chemical modification of polycaprolactone through alkaline-mediated hydrolysis increased overall cardiomyocyte adhesion. The results of this study provide insight into how cardiomyocytes interact with conductive substrates and will inform future research efforts to enhance the functional properties of cardiomyocytes, which is critical for their use in pharmaceutical testing and cell therapy.

A new sensitive electrochemical sensor for the detection of copper ions based on the copper ion assisted etching of Au@Ag nanoparticles was developed in this work. Since copper ions could greatly catalyze the etching process of the silver shell of Au@Ag nanoparticles in the presence of thiosulfate solutions, leading to an obvious decrease of the linear sweep voltammetry (LSV) signals of silver, the concentration of the copper ions, therefore, can be measured. Under the optimized conditions, the electrochemical sensor exhibited excellent sensitivity and selectivity for Cu(2+), with wide linear ranges of 1 nM to 100 μM, and the detection limit of 0.3 nM. In addition, this method was successfully applied for the analysis of Cu(2+) in river water and exhibited good analytical performance.

An adsorbent for CO2 capture was prepared by the grafting of acrylonitrile (AN) onto viscose fibers (VFs); this was followed by amination with triethylene tetramine (TETA). The effects of the reaction conditions, such as the concentrations of the monomer, initiator, and nitric acid, on the grafting degree and grafting efficiency were studied. The adsorption performance of the adsorbent for CO2 was evaluated by fixed-bed adsorption. The highest dynamic adsorption capacity of the adsorbent for CO2 was 4.35 mmol/g when the amine content of the adsorbent VF–AN–TETA reached 13.21 mmol/g. Compared with the polypropylene (PP)-fiber-based adsorbent (PP–AN–TETA), VF–AN–TETA with hydroxyl groups on the fibers facilitated the diffusion of CO2 and water and led to a higher CO2 adsorption capacity than that of PP–AN–TETA. The VF–AN–TETA adsorbent also showed good regeneration performance: its CO2 adsorption capacity could still retain almost the same capacity as the fresh adsorbent after 10 adsorption–desorption cycles. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 132, 42840.

A low-cost solid amine adsorbent for CO2 capture was prepared by using sugarcane bagasse (SB), a dominant agro-industrial residue in the sugar and alcohol industry as raw materials. In this preparation process, acrylamide was grafted on SB, and the grafted fiber was then aminated with different type of amine reagents to introduce primary and secondary amine groups onto the surface of SB fibers. The graft and amination conditions were optimized. The prepared solid amine adsorbent showed remarkable CO2 adsorption capacity and the adsorption capacity of the solid amine adsorbent could reach 5.01 mmol CO2/g at room temperature. The comparison of adsorption capacities of amine fibers aminated with various amination agents demonstrated that fibers aminated with triethylenetetramine would obtain higher adsorption capacities and higher amine efficiency. These adsorbents also showed good regeneration performance, the regenerated adsorbent could maintain almost the same adsorption capacity for CO2 after 10 recycles.