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The aims of this study were to investigate glucosinolate variations in Chinese cabbage cultivars at different growth periods. Glucosinolates in two types of Chinese cabbage (Xiayangbai and Zaoshu-5) at different growth periods (seeds, germination, seedling, and rosette period) were investigated. Thirteen glucosinolates were identified and quantified using UHPLC-Q-TOF-MS. Concentrations of the glucosinolates were significantly different between Xiayangbai and Zaoshu-5. The seed period generated the highest concentration of glucosinolates, and aliphatic glucosinolate predominated in seeds, seedling, and leaves of the rosette as well as during germination. However, the dominant glucosinolate in the roots was an aromatic glucosinolate (gluconasturtiin). In addition, glucoerucin was only found in the roots of rosettes. There were positive significant correlations with each other among gluconapin, glucobrassicanapin, glucoraphanin, glucoalyssin, and 4-hydroxyglucobrassicin. Our results released the metabolism pathways of glucosinolates in Chinese cabbage, which provided scientific evidence to develop functional foods with higher glucosinolate.

In the fretting wear process, wear particles are referred to as the third-body flow in the contact region. During cyclic slip motions, a part of particles are ejected out of the contact region after a certain number of fretting cycles. The rest particles are attached to contact surfaces and consolidated to form a debris layer, which plays an important role in the fretting wear process. In the present work, a fretting wear model incorporating the evolution of the debris layer is proposed within the framework of finite element analysis to predict the wear profile under different fretting conditions. In order to describe the evolution of the debris layer, the dynamic volume fraction of ejected particles is related to the accumulation of trapped debris volume. Furthermore, the Ohno–Wang cyclic plasticity model is employed to describe the cyclic plastic deformation of Ti-6Al-4V alloy. The major contribution of the present work is to study the influence of the accumulative ratcheting deformation and debris layer on the wear profile. Different wear configurations are considered in the simulations to validate the predictive ability of the proposed wear model. The simulation results show that the proposed approach is able to provide a reasonable prediction of the wear profiles in different wear configurations.

Link Prediction, which aims to infer the missing or future connections between two nodes, is a key step in many complex network analysis areas such as social friend recommendation and protein function prediction. A majority of existing efforts are devoted to define the influence of neighbor nodes. However, even though recent studies show that node attributes have an added value to network structure for accurate link prediction, it still remains ignoring the real node influence. To address this problem, in this paper we investigate influential node identification technique to formulate a node ranking-based link prediction metric. The general idea of our approach is to exploit the ranking score as the contribution of a common neighbor. Such fundamental mechanism preserve both local structure and global information. Experimental results on real-world networks with two scenario demonstrate that our proposed metrics achieves better performance than existing state-of-the-art local and global similarity methods.

Sixty-one novel steroidal imidazolium salt derivatives were synthesized and evaluated in vitro against a panel of human tumor cell lines. The results showed that diosgenin‒imidazolium salt derivatives displayed much higher cytotoxic activities than cholesterol‒imidazolium salts and dehydroepiandrosterone‒imidazolium salts. The SARs results suggested that the existence of substituted 5,6-dimethyl-benzimidazoles or benzimidazole ring and substitution of the imidazolyl-3α-position with a 2-bromobenzyl or 2-naphthylmethyl group could be critical for promoting cytotoxic activity. Diosgenin‒imidazolium salt a30 was found to be the most potent compound with IC50 values of 0.44–0.79 μM against five human tumor cell lines. Compound a24 showed inhibitory activity selectively against SMMC-7721 cell lines with IC50 value of 0.21 μM and 54-fold more sensitive to DDP. Moreover, compound a30 inhibited cell proliferation through inducing the G0/G1 cell cycle arrest and apoptosis in SMMC-7721 cells.

Background: Most gastric cancer (GC) patients are diagnosed at an advanced stage, which indicates their poor prognosis. We aimed to investigate novel fecal microbial markers for clinical application in the screening and early diagnosis of gastric cancer (GC). Methods: This is an observational study from three cohorts. In discovery cohort, 16S rRNA gene analysis was performed in paired samples (gastric tissues, feces) from GC and CG patients to determine differential microbes. The relative abundances of the differential microbes were detected using qPCR in training cohort. The diagnostic efficacy of fecal marker Sa/Sc was validated in validation cohort. Findings: 575 gastric cancer (GC) patients, 468 chronic gastritis (CG) patients were enrolled from ten hospitals in China. Significant enrichments of Streptococcus anginosus (Sa) and Streptococcus constellatus (Sc) in both cancerous tissues (P < 0·05) and feces ( P < 0·0001) were observed in patients with intraepithelial neoplasia, early and advanced GC. Either the marker parallel test Sa ∪ Sc or single marker Sa/Sc demonstrated superior sensitivity (Sa: 75·6% vs. 72·1%, P

Most patients with gastric cancer (GCa) are diagnosed at an advanced stage. We aimed to investigate novel fecal signatures for clinical application in early diagnosis of GCa.This was an observational study that included 1043 patients from 10 hospitals in China. In the discovery cohort, 16S ribosomal RNA gene analysis was performed in paired samples (tissues and feces) from patients with GCa and chronic gastritis (ChG) to determine differential abundant microbes. Their relative abundances were detected using quantitative real-time polymerase chain reaction to test them as bacterial candidates in the training cohort. Their diagnostic efficacy was validated in the validation cohort.Significant enrichments of Streptococcus anginosus (Sa) and Streptococcus constellatus (Sc) in GCa tumor tissues (P.05) and feces (P.0001) were observed in patients with intraepithelial neoplasia, early and advanced GCa. Either the signature parallel test Sa∪Sc or single signature Sa/Sc demonstrated superior sensitivity (Sa: 75.6% vs 72.1%, P.05; Sc: 84.4% vs 64.0%, P.001; and Sa∪Sc: 91.1% vs 81.4%, P.01) in detecting early GCa compared with advanced GCa (specificity: Sa: 84.0% vs 83.9%, Sc: 70.4% vs 82.3%, and Sa∪Sc: 64.0% vs 73.4%). Fecal signature Sa∪Sc outperformed Sa∪CEA/Sc∪CEA in the discrimination of advanced GCa (sensitivity: 81.4% vs 74.2% and 81.4% vs 72.3%, P.01; specificity: 73.4% vs 81.0 % and 73.4% vs 81.0%). The performance of Sa∪Sc in the diagnosis of both early and advanced GCa was verified in the validation cohort.Fecal Sa and Sc are noninvasive, accurate, and sensitive signatures for early warning in GCa. (ClinicalTrials.gov, Number: NCT04638959).

Background Data from preclinical and clinical studies support the evaluation of histamine 4 receptor antagonists in the treatment of asthma. Toreforant is a selective histamine 4 receptor antagonist that could be effective in patients with eosinophilic asthma. Objective To evaluate the efficacy and safety of toreforant in patients with eosinophilic, persistent asthma that was inadequately controlled despite current treatment. Methods In this phase 2a, multicenter, randomized, double-blinded, parallel-group, placebo-controlled, proof-of-concept study, 162 eligible patients were randomized (1:1) to placebo or 30 mg of toreforant once daily through week 24 and followed for 4 weeks. The primary end point was change from baseline in pre-bronchodilator percent-predicted forced expiratory volume in 1 second at week 16. Secondary end points included change from baseline at week 16 in postbronchodilator percent-predicted forced expiratory volume in 1 second, Asthma Control Questionnaire scores, weekly averages of Daytime and Nighttime Asthma Diary Symptom Scores, and weekly average of number of puffs in a day that rescue medication was used. Results There was no significant difference between groups in pre-bronchodilator percent-predicted forced expiratory volume in 1 second at week 16 (difference in least-square means −0.19%; 95% confidence interval −3.01 to 2.64; P = .90). Similarly, there were no significant differences between groups at week 16 in changes from baseline in the secondary end points (P ≥ .30). Toreforant was generally well tolerated. No deaths or serious adverse events were reported at any time point. Conclusion Toreforant, at the dose tested, failed to provide therapeutic benefit in this population of patients with uncontrolled, eosinophilic, persistent asthma. Trial Registration ClinicalTrials.gov, NCT01823016

The effects of NaCl addition on the gelling and water holding properties of egg white/yolk gels were studied via solubility, surface hydrophobicity, reduced sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Fourier transform infrared spectra (FTIR), textural analysis, low-field nuclear magnetic resonance (LF-NMR) and centrifugation. Results showed that more solubility and surface hydrophobicity increase of egg yolk dispersions were observed than that of egg white dispersions. SDS-PAGE results indicated that the different change trend of surface hydrophobicity between two egg proteins was closely related with the dissociation of egg yolk granule proteins. NaCl-induced protein heat denaturation will result in the decrease of ordered secondary structure (α-helix and β-sheet) by breaking hydrogen bond for both egg protein gels. A rapid decrease (p

The aim of this study was to verify the influence of selected phosphate salts (sodium diphosphate and trisodium phosphate) on the gelling properties and water state of whole egg gel. As shown by the results, the gel and water holding properties of whole egg was effectively improved after the addition of sodium diphosphate and trisodium phosphate, possibly through affecting the solubility, surface hydrophobicity, z-average particle size and pH of liquid egg dispersions. The difference in the viscoelastic properties of whole egg gels brought by two phosphate salts was related to their obvious difference in calculated ionic strength and pH. As the addition level of phosphate salts increased, the protein secondary structure after gelation was changed remarkably, characterized by the decrease of α-helix content and the increase of β-sheet content. The gel β-sheet content was positively correlated with fracture strain and percentage of bound water and immobilized water, while the α-helix content was negatively correlated with fracture strength. The scanning electron microscope (SEM) results showed that the addition of phosphate salts would facilitate the formation of a fine high strength stranded structure. Moreover, the color characteristics of whole egg gels can be more effectively improved by sodium diphosphate in comparison with trisodium phosphate.

Globally consumed kimchi is manufactured through fermenting cruciferous vegetables containing indole glucosinolates (IG). But few reports describe the IG metabolism during the fermentation. Here, we show that indole-3-carbinol (I3C), a breakdown product of IG, is transformed during the kimchi fermentation into 3,3'-diindolylmethane (DIM) and 2-(indol-3-ylmethyl)-3,3'-diindolylmethane (LTr1). LTr1 was found to kill the acute myeloid leukemia (AML) cells with FMS-like tyrosine kinase 3 (FLT3) receptor mutations, by inhibiting the FLT3 phosphorylation and the expression of downstream proteins (STAT5, ERK, and AKT). In the immune-depleted mice xenografted with human MV4-11 cells, LTr1 was demonstrated to reduce the tumor growth and synergize with sorafenib, an anti-AML agent in clinic. The work updates the chemical and biological knowledge about kimchi, and in particular establishes LTr1 as an FLT3 inhibitor that is effective and synergistic with sorafenib in treating AML.

The efficiency of egg white protein microparticle (EWPM) and pectin sol (PS) addition in blocking flow behavior of light mayonnaise was investigated in this study. The texture properties, color, microstructure and thermal resistance were also measured for better understanding of synergistic effect of EWPM and PS on characteristics of light mayonnaise. At ratio of 2:4 (in weight ratio of PS and EWPM), the sample showed higher viscosity and hardness, attributed to the formation of larger protein aggregates induced by repulsion between protein and pectin molecule. The speculation was verified through the microstructure of mayonnaise samples observed by laser light confocal microscope. With the amount of EWPM increased, the yellow value of light mayonnaise increased, but thermal resistance decreased. For EWPM-rich samples, moderate heat treatment can strengthen the interaction between particles, inducing the increase of viscosity.

Egg white protein is a kind of protein resource with distinctive nutritional value and functional properties, while performing weak emulsifying stability under neutral and alkaline conditions, limiting application in food industry. This study, we investigated the effect of enzyme on characteristics of egg white protein (EWP) and synergistic efficiency of pectin addition on properties (thermal stability, salt resistance and antioxidant activity) of emulsions stabilized by original or hydrolyzed EWP. The EWP solutions were incubated at pH 7.0, under 50 °C for 2 h, with various amount of enzyme (0%, 0.5%, 1%, 2%, and 4%) added in. With enzyme concentration increased, more ovotransferrin and ovalbumin were hydrolyzed, and more hydrophobic amino acids exposed to polar environment, especially tyrosine. In addition, the DPPH and ABTS radical scavenging activity of EWP increased with enzyme concentration increased. Pectin addition can effectively improve the stabilization of the emulsion droplets, inducing smaller effective diameter and polydispersity index. In comparison, the emulsions stabilized by hydrolyzed EWP with 0.3% pectin behaved better thermal and salty stability, while with poorer antioxidant capacity attributed to weaker intermolecular interactions. The rheological measurement showed that the viscosity of hydrolyzed EWP stabilized emulsion was relatively lower and G′ was more dependent on frequency, indicating weaker cross-links among droplets. The results may provide theoretical guidance for application of enzymatic and polysaccharide blends in improving protein functionality.

Ethnopharmacological relevance Abietic acid (AA), an antibacterial terpenoid, was initially isolated from rosin which has been used as a traditional Chinese medicine to treat psoriasis. In our previous works, we found that water-processed rosin (WPR) can alleviate imiquimod (IMQ)-induced psoriasis-like inflammation in mice. However, the efficacy of AA, the main component of WPR, against psoriasis remains unclear. Materials and methods In this study, we confirmed the anti-psoriasis efficacy of AA (40 mg/kg daily for 7 days) in IMQ-induced psoriasis-like inflammation BALB/c mouse model by the psoriasis area severity index (PASI), flow cytometry, ELISA, histopathological and immunohistochemical analysis. Furthermore, we detected the relative abundance of gut microbe using high-throughput 16S rRNA gene sequencing to validate whether AA modulate gut microbe. Result Oral administration of AA ameliorates IMQ-induced psoriasis-like skin inflammation through reducing PASI scores, regulating the balance of Th17/Treg cells in the mouse spleen, and downregulating the level of serum cytokines such as TNF-α, IL-17A, TGF-1β, and IL-23. 16S rRNA gene sequencing revealed that the relative abundance of gut bacteria related to inflammation, such as, Anaerotruncus and Christensenella at genus level were decreased, while Kurthia, Citrobacter, and Klebsiella at genus level were increased in AA group mice. Additionally, the correlation analysis illustrated that the key microbiota had a close relationship with the psoriasis-like inflammation related indexes. Conclusion AA might exert the anti-psoriasis effect via inhibiting Th17-related immune responses, hinting that it might be a candidate for treating psoriasis. Meanwhile, the alteration of intestinal microbiota by AA treatment is another possible explanation for the amelioration of imiquimod-induced psoriasis-like inflammation.

Car-following behavior is strongly related to the dynamic performance and safety of vehicles, and these behaviors must be studied more comprehensively. This study first quantitatively analyzes the relationship between time to collision and car-following behavior, and then proposes the concept of collision sensitivity coefficient. Based on the full velocity difference model, we introduce the collision sensitivity coefficient into the car-following model to explore its effect on vehicle dynamic performance and safety from a different perspective. The stability of traffic flow is investigated using linear stability theory and obtain the neutral stability condition of the proposed model. Numerical simulation results show that the proposed model can improve the stability of traffic flow and successfully suppress traffic jams. The computation results using various safety evaluation indicators reveal that the proposed model not only has better dynamic performance than the full velocity difference model but also can effectively improve the safety of vehicles. We conclude that collision sensitivity substantially affects car-following behavior.

This study investigated the potential of egg white protein (EWP) to be developed into a kind of Pickering stabilizer for oil-in-water emulsions. The EWP microparticles were formed by heating at 90 °C for 45 min, followed by homogenization under low pressure. The characteristics and microstructure of microparticles prepared under various pH (3.0, 3.8) and protein concentration (2–10%) were tested. Simultaneously, the properties of Pickering emulsions integrated by EWP microparticles, with fibrous or granular morphology, were investigated. At pH 3.0, the particles may transfer from fibrous structure to granular structure with protein concentration increased or salt addition. At pH 3.8, granular microparticles were formed under various protein concentration. The structure of EWP microparticles were mainly maintained by hydrophobic interactions and hydrogen bondings. The granular particles showed higher surface loading of protein and viscoelastic moduli in the integrated Pickering emulsions. These results have important implications for the formulation and production of emulsion based semi-solid products, using egg white protein as emulsifier and fat substitute.

Among different types of crashes, hit-and-run is driver’s failure to stop after a vehicle crash. There are many accidents where drivers could actually be at fault or totally innocent, and leaving the scene would turn an innocent driver into a criminal. The current paper aims to contribute to the literature by exploring the association of different variables pertaining to the condition of infrastructure, environment, driver, population of the area, and crash severity and type with hit-and-run crashes. The analysis is performed for two data sets: (i) crashes where the driver was distracted; and (ii) crashes where driver was not distracted. Hit-and-run crash data with corresponding factors are police-reported data for crashes within Cook County, Illinois, occurring between 2004 and 2012. A logistic regression model assessed 43 variables within 16 categories for statistically significant association with hit-and-run crashes, for drivers with and without distraction. For both driver distraction statuses, 17 variables were associated with a significant increased probability of a hit-and-run crash and 10 variables were associated with a significant decreased probability. Additionally, it was found that crashes on curve level and curve hillcrest road alignment types were associated with increased likelihood of a hit-and-run crash when the driver was distracted and decreased likelihood when the driver was not distracted. Variables related to hit-and-run crashes vary depending on driver’s distraction status. When comparing likelihood to flee the scene after a crash, non-distracted drivers are 27% less likely to do so compared to distracted drivers.

Hit-and-run crashes are accidents where drivers of striking vehicles fail to stop after crashes. Without helping victims or reporting accidents to associated authorities could increase the likelihood of serious injuries and even fatalities. In order to reduce hit-and-run crashes, it is important to understand factors contributing to decisions of fleeing crash scenes. In current study, various factors which could affect occurrences of hit-and-run crashes were thoroughly investigated against six different improper driving behaviors. Logistic regression models were established to facilitate the analysis. Police-reported crash data within Cook County, Illinois, USA between 2004 and 2012 were used in this study. The results showed that variables contributing to hit-and-run crashes varied for different improper driving behaviors. Among six established models, “following too closely” and “distraction by phone” models had most statistically significant variables. This study also concluded that following variables would increase the likelihood of hit-and-run crashes in at least one model: multiple vehicle crash, weekend, population of 2,500 – 5,000, population of 5,000 – 10,000, national highway system, traffic signal, yield sign, shoulder, darkness, and less than three lanes. The results of current study could offer important insights for reducing hit-and-run crashes in both planning and operational levels.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide. Endoplasmic reticulum stress (ERS) is generally activated in HCC and is important for the sensitivity of HCC to anticancer drugs. ERS-dependent autophagy is a crucial mechanism affecting the sensitivity of HCC to anticancer drugs, but the mechanism by which ERS regulates autophagy is not well understood. Zinc finger protein 263 (ZNF263) is a transcription factor member of the zinc finger family. However, its functional role in HCC remains to be studied. In the current study, we investigated the role of ZNF263 in regulating ERS-induced chemoresistance in HCC and its possible mechanism. We found that ZNF263 was the most significant ERS-specific super-enhancer bounding transcriptional factor and was up-regulated in HCC patients and cell lines. Further, ZNF263 expression correlated with ERS, clinical stage and shorter survival in HCC patients. ZNF263 knockdown by RNA interference results in decreased proliferation, apoptosis resistance, and chemoresistance. Further study showed that ZNF263 increased chemoresistance by activating ERS-related autophagy. In conclusion, our study highlights ZNF263 as a functional ERS-related tumor activator and indicates it as a potential target for HCC therapy.

Aims Placental tissues from patients with preeclampsia (PE) and in the lipopolysaccharide (LPS)-induced PE-like model were used to investigate the implication of placental inflammation and apoptosis in PE. Whether the beneficial effects of nicotine are related to inhibition of placental inflammation and apoptosis in the PE-like model were investigated. Main methods Placental apoptosis was detected in PE patients and the PE-like rat model by TUNEL staining. Changes in the number of CD68+ macrophages in placental tissues from PE patients were detected by immunofluorescent staining. The mRNA expression of the pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin (IL-1β), MCP-1, and proteins involved in extrinsic or intrinsic apoptosis signaling in the PE-like model was determined by qRT-PCR; immunofluorescent staining was used to detect the expression of TNF-α receptor (TNFR1), MCP-1 and apoptosis-related proteins. Key findings Placental apoptosis was increased in both PE patients and the PE-like model, more macrophages infiltrated into placenta in PE patients. A significant upregulation in mRNA expression of TNF-α, IL-1β, MCP-1, and caspase 3, caspase 8, caspase 9 was found in the PE-like rats compared to the control animals, the immunoreactivity of placental MCP-1, TNFR1, and apoptosis-related proteins (caspase 3, caspase 8, caspase 9, Bax) was also enhanced; nicotine treatment significantly reversed those changes. Significance Our data suggests that the protective effects of nicotine are associated with inhibiting placenta inflammation and apoptosis, and nicotine might be a potentially therapeutic candidate for preventing preeclampsia.

Development of suitable solid membrane electrolyte for all-solid-state lithium ion battery is of great importance to address the safety issue arisen from the current lithium ion battery technology. Herein, we report the synthesis and properties of a poly(ethylene oxide)-based, crosslinked solid membrane electrolyte with nanocages of polyhedral oligomeric silsesquioxane through UV-induced crosslinking technique. Benefiting from the crosslinked structure, the synthesized membrane electrolyte exhibits an improved mechanical strength and electrochemical stability compared to the sample without crosslinked structure. The optimized membrane electrolyte has the ionic conductivity of 3.83 × 10−4 Scm−1 at 60 °C with an electrochemical window of 5.3 V. The thus-assembled battery using lithium plate as anode and lithium iron phosphate as cathode delivers an initial discharge capacity of 150 mAhg−1 at 60 °C, higher than that of battery assembled from membrane electrolyte without crosslinked structure. Although the battery is more stable than that assembled from membrane electrolyte without crosslinked structure, the initial discharge capacity decreases to 139 mAhg−1 after 42 charging-discharging cycles. Nevertheless, the results presented here demonstrate that the UV-induced crosslinking strategy can be an effective approach for the practical synthesis of solid-state membrane electrolyte.

Development of membrane electrolyte with reasonable proton conductivity at elevated temperature without external humidification is essential for practical applications of elevated temperature proton exchange membrane fuel cells. Herein, a novel polymer electrolyte composite membrane using imidazole as anhydrous proton carriers for elevated temperature fuel cells is investigated. The imidazole moieties are immobilized inside the Nafion/poly(tetrafluoroethylene) (PTFE) composite membrane through in situ formation of imidazole functionalized silica nanoparticles in Nafion dispersion. The thus-formed membrane exhibits strong Coulombic interaction between negatively charged sulfonic acid groups of Nafion and protonated imidazole moieties, leading to an anhydrous proton conductivity of 0.018 S cm −1 at 180 °C. With the introduction of PTFE matrix, the mechanical strength of the membrane is greatly improved. The peak power density of a single cell assembled from the hybrid membrane is observed to be 130 mW cm −2 under 350 mA cm −2 at 110 °C without external humidification and it remains stable for 20 h continuous operation. The obtained results demonstrate that the developed composite membranes could be utilized as promising membrane electrolytes for elevated temperature fuel cells.

We developed the first one-pot synthesis of structurally diverse pyrrolo[3,4-c]quinoline-1-one derivatives via a three-component cascade reaction of enaminones, amines, and isatin under acidic condition. This reaction proceeds through an unusual hydride transfer from in situ formed dimethylamine to a carbocation intermediate to generate the 3-methylene group. This method is straightforward, high-yield, easy to operate, and shows a broad substrate scope, thus potentially useful for diversity-oriented synthesis.

We report the first oxidative condensation between N,N-dimethylenaminones with amines to form 1,4-dihydropyridines in moderate to good yields, promoted by oxone and trifluoroacetic acid in PEG-400. This reaction features an unusual oxidation of in situ formed dimethylamine to efficiently provide the 4-methylene of 1,4-dihydropyridines, and a highly environment-friendly reaction condition.

A novel TiO 2 /diatomite composite (TD) was prepared and then characterized by scanning electron microscope (SEM) and Fourier Transform Infrared (FTIR). The results of SEM showed that after modification, the porous surface of diatomite was covered with TiO 2 . Both diatomite and TD had clear disc-shaped structures with average grain diameters of around 25 μm. Then TD and pure TiO 2 were applied in the purification of phosvitin phosphopeptides (PPPs) from the digest of egg yolk protein, and a comparative study of adsorption properties of PPPs on TD and TiO 2 was performed. In the study of adsorption kinetics, the adsorption equilibrium of PPPs on TD and TiO 2 fitted well with the Langmuir model, and the time needed to reach adsorption equilibrium were both around 10 min. The maximum dynamic adsorption capacity of TD (8.15 mg/g) was higher than that of TiO 2 (4.96 mg/g). The results of repeated use showed that TD and TiO 2 were very stable after being subjected to ten repeated adsorption–elution cycles, and TD could easily be separated from aqueous solution by filtration. On the other hand, the present synthetic technology of TD was very simple, cost-effective, organic solvent-free and available for large-scale preparation. Thus, this separation method not only brings great advantages in the purification of PPPs from egg yolk protein but also provides a promising purification material for the enrichment of phosphopeptides in proteomic researches.

An electrochemical indirect competitive immunoassay protocol as a promising cytosensing strategy was developed to detect integrin β1 expression on human breast cancer MCF-7 cells and adriamycin-resistant human breast cancer MCF-7 (MCF-7/ADR) cells and quantify the cell number. Integrin α5β1 was adsorbed on the gold-nanoparticle modified glassy carbon electrode to bind integrin β1 monoclonal antibody (anti-CD29 mAb). A sandwich structure was then formed using nanocomposites which consisted of horseradish peroxidase (HRP) labeled anti-antibody and gold nanoparticles. HRP bound on the electrode surface could cause an amperometric response of the hydroquinone-H(2)O(2) system. The assembly of the sandwich structure was inhibited by tumor cells to give decreased enzyme-catalytic signals due to the capture of anti-CD29 mAb by integrin β1 on cell membranes. Under optimal conditions the relative current change (S) was proportional to the cell concentration from 1.6 × 10(3) to 2.0 × 10(6) cells mL(-1) with a detection limit of 700 cells mL(-1). Integrin β1 expression in MCF-7/ADR cells was found to be significantly higher than that in MCF-7 cells, indicating the increased adhesion ability of MCF-7/ADR cells.

Series of mono-dispersed bovine serum albumin (BSA)‐conjugated PbS/Ag 2 S core/shell nano-composites with different Pb/Ag ratios had been successfully synthesized by an ion-exchange method under the gentle conditions using BSA-conjugated PbS nano-crystals as precursors, which were prepared by a biomimetic method. Fourier transform infrared spectra analysis and transmission electron microscopy (TEM) observation demonstrated that BSA was a key factor to control the morphology and size of final products. Additionally, the real-time TEM observation, X-ray powder diffraction and atomic absorption spectroscopy analysis were applied to monitor the synthesis process. The results indicated that the shell thickness and ratio of Pb to Ag could be controlled by adjusting the ion-exchange time. Both metabolic and morphological methods revealed that the proliferation of rat pheochromocytoma (PC 12) cells could be inhibited by BSA-conjugated PbS/Ag 2 S core/shell nano-composites, and the antineoplastic activity was Pb/Ag ratio-dependent. It might be explained by a Trojan horse-type mechanism. Summarily, the present study would be helpful to find a new core/shell nano-composite with higher and controllable antineoplastic activity due to the synergistic reaction of different metal ions.

Conducting polymer nanocomposites have attracted a wide attention in material chemistry and analytical chemistry. In this work, poly(methylene blue) doped silica nanocomposites (PMB@SiO2(nano)) on glassy carbon electrode (GCE) were synthesized based on a two-step electropolymerization. Compared with poly(methylene blue) film, PMB@SiO2(nano) had more advantages in facilitating electron transfer between glucose oxidase (GOx) and the electrode surface. GOx immobilized on PMB@SiO2(nano) underwent a direct and reversible electrochemical reaction involving two-electron and two-proton exchange. A reagentless glucose biosensor using the nanocomposite modified electrode was developed. The calibration curve was linear over a glucose concentration range of 0.01–1.11 mM with a correlation coefficient of 0.998 and a detection limit (3σ) of 3 μM. The apparent Michalis–Menten constant, Km, for the enzymatic reaction was 0.50 mM. The developed biosensor presented good accuracy, repeatability, reproducibility and stability as well as an excellent ability to resist interference from ascorbic acid and uric acid species. The investigation indicates that PMB@SiO2(nano) has a good potential for application in construction of the third-generation enzyme biosensor as a conducting matrix material.

The quartz crystal microbalance (QCM) dynamic measurements indicate that ginsenoside Rh(2) (G-Rh(2)) could inhibit the proliferation of adriamycin-resistant human breast cancer MCF-7 cells (MCF-7/ADR) in a concentration-dependent way. The combined treatment of G-Rh(2) with adriamycin (ADR) at non-effect dosage resulted in the higher inhibition efficiencies and the increased cell-death velocity, suggesting excellent ability of G-Rh(2) for reversal of multidrug resistance in MCF-7/ADR cells. The cytotoxic effect of the ADR-G-Rh(2) combination was evaluated with the modified Burgi formula (Jin equation) based on the QCM responses. It presented apparent synergism, indicating the potential ability of G-Rh(2) in tumor therapy. Fluorescent microscopic inspection and methyl thiazolyl tetrazolium (MTT) assay were also carried out and exhibited the comparable results to QCM analysis. The present work may lay an experimental foundation for the application of ginsenosides in cancer therapy, especial in multidrug resistance research.

Membrane proteins account for about 30% of the genomes sequenced to date and play important roles in a variety of cellular functions. However, determining the three-dimensional structures of membrane proteins continues to pose a major challenge for structural biologists due to difficulties in recombinant expression and purification. We describe here a high throughput pipeline for Escherichia coli based membrane protein expression and purification. A ligation-independent cloning (LIC)-based vector encoding a C-terminal green fluorescence protein (GFP) tag was used for cloning in a high throughput mode. The GFP tag facilitated expression screening in E. coli through both cell culture fluorescence measurements and in-gel fluorescence imaging. Positive candidates from the GFP screening were subsequently sub-cloned into a LIC-based, GFP free vector for further expression and purification. The expressed, C-terminal His-tagged membrane proteins were purified via membrane enrichment and Ni-affinity chromatography. Thermofluor technique was applied to screen optimal buffers and detergents for the purified membrane proteins. This pipeline has been successfully tested for membrane proteins from E. coli and can be potentially expanded to other prokaryotes.

Monomers of (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG), (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin 3-O-(3-O-methyl) gallate (EGCG3''Me) and (-)-3-O-methyl epicatechin gallate (ECG3'Me) (purity, >97%) were successfully prepared from extract of green tea by two-time separation with Toyopearl HW-40S column chromatography eluted by 80% ethanol. In addition, monomers of (-)-catechin (C), (-)-gallocatechin (GC), (-)-gallocatechin gallate (GCG), and (-)-catechin gallate (CG) (purity, >98%) were prepared from EC, EGC, EGCG, and ECG by heat-epimerization and semi-preparative HPLC chromatography. With the prepared catechin standards, an effective and simultaneous HPLC method for the analysis of gallic acid, tea catechins, and purine alkaloids in tea was developed in the present study. Using an ODS-100Z C(18) reversed-phase column, fourteen compounds were rapidly separated within 15min by a linear gradient elution of formic acid solution (pH 2.5) and methanol. A 2.5-7-fold reduction in HPLC analysis time was obtained from existing analytical methods (40-105min) for gallic acid, tea catechins including O-methylated catechins and epimers of epicatechins, as well as purine alkaloids. Detection limits were generally on the order of 0.1-1.0ng for most components at the applied wavelength of 280nm. Method replication generally resulted in intraday and interday peak area variation of

Block diagonalization (BD) is an efficient precoding technique that eliminates inter-user interference in downlink multiple-input multiple-output (MIMO) systems. User selection strategies applied to multiuser MIMO systems with BD are investigated in this article. To enhance the capacity of multiuser MIMO systems, an equivalent capacity maximum (ECM) user selection strategy is proposed with low computational complexity. Considering both the factors of channel correlations and channel conditions, the proposed strategy can select a group of users to serve for maximizing the total throughput. Simulation results indicate that, for various channel conditions, proposed ECM strategy gains a better performance compared with traditional user selection strategies, and achieves a near optimal throughput as the exhaustive search.

Highly photo-catalytically active ZnO photocatalyst was prepared by sol–gel method with the assistance of cetyltrimethylammonium bromide (CTAB). The surface parameters, structure, morphology and the photoinduced charge separation rate of the photocatalyst prepared (ZnO–CTAB) were characterized by Brunauer–Emmett–Teller (BET) method, X-ray diffraction (XRD), scanning electron microscopy (SEM) and surface photovoltage spectroscopy (SPS), respectively. The results reveal that CTAB alters the surface parameters and the morphology, and enhances the photoinduced charge separation rate of ZnO. The photocatalytic activity of ZnO–CTAB for decolorization of methyl orange (MO) solution was evaluated. The results show that the photocatalytic activity of ZnO–CTAB is three times of that of the reference ZnO and the possible reason was discussed.

The dynamic response of ionospheric plasmas is modeled for current sources induced by a pulsed tether. A new method was developed which combines analytic and numerical techniques to study the dynamic response of a 2-D magnetoplasma to a time-dependent current source imposed across the magnetic field. The set of cold electron/ion plasma equations and Maxwell's equations are first solved analytically in ( k ,ω) space. Inverse Laplace and 2-D complex Fast Fourier Transform (FFT) techniques are subsequently used to numerically transform the radiation fields and plasma currents from ( k ,ω) space to ( r ,t ) space. These results show that ionospheric plasmas respond to current sources induced by a pulsed tether through the excitation of whistler waves and formation of an expanding local current loop, induced by field-aligned plasma currents. The current loop consists of two antiparallel field-aligned current channels concentrated at the ends of the imposed tether current and a cross-field current region connecting these channels. The latter currents are driven by an electron Hall drift.

Carbon aerogels were synthesized by the solution-sol-gel polymerization of resorcinol(R) and formaldehyde(F) with silica colloidal nanoparticles as additives in a basic aqueous solution followed by supercritical drying,pyrolysis and HF etching.The R/F molar ratio was maintained at 0.5 and the concentration of R+F in solution was varied.The evolution of porosity from hydrogels to carbon aerogels was investigated by nitrogen adsorption.The effect of R+F concentration and size of the silica colloidal nanoparticles on porosity and mesopore ratios were investigated under the same concentration of silica colloidal nanoparticles at 15 g/100 mL.Results indicated that the volume shrinkage of carbon precursors during supercritical drying and pyrolysis can be reduced by the presence of silica colloidal nanoparticles.The mesopore ratio increased with increasing R+F concentration and porosity decreased with increasing size of the silica colloidal nanoparticles.When the R+F concentration was 20 g/100 mL,the densities of the carbon aerogels were 0.22 and 0.26 g/cm3 with mesopore ratios of 96 and 98% for 7 and 12 nm silica colloidal nanoparticles respectively.