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The bioactive ingredients in Semen sinapis were rapidly screened by immobilized β2-adrenoceptor ( β2-AR) and target-directed molecular docking. The methods involved the attachment of β2-AR using any amino group in the receptor, the simultaneous separation and identification of the retention compounds by high-performance affinity chromatography; the binding mechanism of the interesting compound to the receptor was investigated by zonal elution and molecular docking. Sinapine in Semen sinapis was proved to be the bioactive compound that specifically binds to the immobilized receptor. The association constant of sinapine to β2-AR was determined to be 1.36 × 105 M−1 with a value of 1.27 × 10−6 M for the number of binding sites. Ionic bond was believed to be the driving force during the interaction between sinapine and β2-AR. It is possible to become a powerful alternative for rapid screening of bioactive compounds from a complex matrix such as traditional Chinese medicine and further investigation on the drug-receptor interaction. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Fluxes of carbon dioxide (CO2) and methane (CH4) from hydroelectric and water supply reservoirs are receiving increasing attention around the world with a number of research groups having undertaken measurements of these emissions across a range of lakes and reservoirs located in different climates and landscapes. The use of floating chambers (aka flux chambers) is the most common technique for direct measurement of these fluxes. However, the relative performance of different measurement systems, especially different chamber designs, is not well documented. We report the results of an international workshop held in June 2012 at Three Gorges Dam, China, to compare measurements performed by four groups with extensive chamber monitoring experience: the Chinese Academy of Science (China), CSIRO (Australia), SINTEF (Norway), Hydro-Québec/Environnement Illimité (Canada). A fifth group, Eawag (Switzerland), performed hydroacoustic surveys to detect ebullition in the water column. We recommend CH4 as a more suitable trace gas for comparing methodologies due to its relative stability in the surface layer of the water column, for example, it is not subject to significant diurnal changes due to photosynthesis and respiration. Measured fluxes agreed to within 20% between the four teams suggesting that the shape and dimensions of the floating chambers and the chamber gas flow rates (i.e., chamber residence time) did not have an appreciable systematic effect on the measured fluxes for the relatively low wind speeds prevalent at the reservoir. The CO2 and CH4 fluxes measured during the workshop agree well with previous measurements in Three Gorges Reservoir. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction The distribution of metabolites in the different root parts of Cortex Moutan (the root bark of Paeonia suffruticosa Andrews) is not well understood, therefore, scientific evidence is not available for quality assessment of Cortex Moutan. Objective To reveal metabolomic variations in Cortex Moutan in order to gain deeper insights to enable quality control. Methods Metabolomic variations in the different root parts of Cortex Moutan were characterised using high-performance liquid chromatography combined with mass spectrometry (HPLC-MS) and multivariate data analysis. The discriminating metabolites in different root parts were evaluated by the one-way analysis of variance and a fold change parameter. Results The metabolite profiles of Cortex Moutan were largely dominated by five primary and 41 secondary metabolites . Higher levels of malic acid, gallic acid and mudanoside-B were mainly observed in the second lateral roots, whereas dihydroxyacetophenone, benzoyloxypaeoniflorin, suffruticoside-A, kaempferol dihexoside, mudanpioside E and mudanpioside J accumulated in the first lateral and axial roots. The highest contents of paeonol, galloyloxypaeoniflorin and procyanidin B were detected in the axial roots. Accordingly, metabolite compositions of Cortex Moutan were found to vary among different root parts. Conclusion The axial roots have higher quality than the lateral roots in Cortex Moutan due to the accumulation of bioactive secondary metabolites associated with plant physiology. These findings provided important scientific evidence for grading Cortex Moutan on the general market. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The interaction between drugs and receptors is particularly important in revealing the drug acting mechanism and developing new leads. In this work, α-Adrenoceptor ( α-AR) from HEK293 cell line is purified and immobilized on the surface of macro-pore silica gel to prepare an high-performance affinity chromatography stationary phase for the pursuit of drug-receptor interactions by competition zonal elution. Naftopidil is found to have only one type of binding site to α-AR with an association constant of 1.45 × 10 M and a concentration of binding sites of 1.56 × 10 M, while terazosin hydrochloride proves to present two kinds of binding site on the receptor at which the association constants are determined to be 1.61 × 10 M and 2.06 × 10 M, and the corresponding concentrations of the binding sites are 1.56 × 10 M and 1.11 × 10 M, respectively. It is concluded that the stationary phase containing attached α-AR can be used to realize the binding of a drug to the receptor. [ABSTRACT FROM AUTHOR]

The host–guest interaction between sulfobutylether‐β‐cyclodextrin (SBE‐β‐CD) and reserpine (RSP) is described using flow injection‐chemiluminescence (FI‐CL) and site‐directed molecular docking methods. It was found that RSP could inhibit the CL intensity produced by a luminol/SBE‐β‐CD system. The decrease in CL intensity was logarithmic over an RSP concentration range of 0.03 to 700.0 nM, giving a regression equation of ∆I = 107.1lgCRES + 186.1 with a detection limit of 10 pM (3σ). The CL assay was successfully applied in the determination of RSP in injection, saliva and urine samples with recoveries in the range 93.5–106.1%. Using the proposed CL model, the binding constant (KCD‐R) and the stoichiometric ratio of SBE‐β‐CD/RSP were calculated to be 7.4 × 106 M‐1 and 1 : 1, respectively. Using molecular docking, it was confirmed that luminol binds to the small cavity of SBE‐β‐CD with a nonpolar interaction, while RSP targeted the larger cavity of SBE‐β‐CD and formed a 1 : 1 complex with hydrogen bonds. The proposed new CL method has the potential to become a powerful tool for revealing the host–guest interaction between CDs and drugs, as well as monitoring drugs with high sensitivity. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Soil salinity level in shelterbelts under different emitter distance and different planting years was compared using 3 years of monitoring data from a typical oasis located in an extremely arid area in northwest China. The variation trend of salinity level during the whole growing season and in nonirrigation season was analysed. The results indicate that: (1) under narrow emitter distance (1.5 m), the soil layer with the highest salinity level was located deepest (50-85 cm). Under wide emitter distance (3 m), the soil layer with the highest salinity level was located shallower (45-80 cm); (2) drip irrigation effectively decreased the soil salinity level. With the increased in irrigating years, the salt-leaching effect was better. Most of the soil salts were brought downward to the soil layer below 30 cm, 50 cm and 70 cm, respectively, in shelterbelts that have been irrigating for 1 year, 2 years and 3 years; (3) soil salinity level presented an increasing trend during the growing season. The largest change of soil salinity level fore-and-aft the irrigation was found in 20-cm depth, followed by the 40-cm depth and then the 60-cm depth; (4) in nonirrigation season, salt was accumulating at the surface in shelterbelts. Among all the shelterbelts with different forest age, the salinity level on the surface was the highest in the 2-year-old shelterbelt. [ABSTRACT FROM AUTHOR]

A method based on reaction with a diazonium salt was developed to immobilise oriented His-tagged protein onto silica gel. The binding efficiency of the phenylamine-group-coated gel was determined to be 65 %, providing a binding capacity of His-tagged protein up to the gram level. Using His-tagged β-adrenoceptor (β-AR) as a probe, we developed a new mathematical model to elucidate the interactions between the receptor and five ligands (methoxyphenamine, terbutaline, salbutamol, tulobuterol and fenoterol). These drugs proved to only have one type of binding site on the immobilised β-AR, yielding higher association constants and numbers of binding sites than random attachment assays. The association constants determined by the new model positively correlated to the values from a radioligand binding method, with a regression equation of y = 1.75 x − 7.18 and a correlation coefficient of 0.9807. The oriented method resulted in a high binding capacity and quantitative immobilisation of the His-tagged protein. The proposed model can be used to determine the interactions between the ligands and the immobilised protein with the advantages of drug and time saving. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Highlights: [•] We constructed a novel model for revealing drug–protein interactions. [•] Validated application of the model is performed two proteins as probes. [•] The model is drug-saving and rapid comparing with batch affinity assays. [Copyright &y& Elsevier]

P-Glycoprotein (P-gp), an ATP-binding cassette transporter, plays an important role in multidrug resistance (MDR). α-Asarone and β-asarone, bioactive cis- trans isomers found in Acorus tatarinowii Schott, were tested for their potential ability to modulate the expression and function of P-gp in Caco-2 cells. MTT assays revealed that both α-asarone and β-asarone significantly enhanced the vincristine-induced cytotoxicity to cells. β-Asarone was the most potent. Flow cytometry showed that α- and β-asarone increased Rhodamine 123 (Rh123) uptake and inhibited Rh123 efflux in Caco-2 cells in a concentration-dependent manner. Furthermore, P-gp expression and P-gp mRNA in cells were decreased by exposure to α- and β-asarone. In addition, β-asarone increased the inhibition of P-gp activity in cells more than α-asarone. Thus, α- and β-asarone effectively reversed MDR by inhibiting P-gp function and expression. [ABSTRACT FROM AUTHOR]

A new oriented method using a diazonium salt reaction was developed for linking β2-adrenoceptor (β2-AR) on the surface of macroporous silica gel. Stationary phase containing the immobilised receptor was used to investigate the interaction between β2-AR and ephedrine plus pseudoephedrine by zonal elution. The isotherms of the two drugs best fit the Langmuir model. Only one type of binding site was found for ephedrine and pseudoephedrine targeting β2-AR. At 37 °C, the association constants during the binding were (5.94±0.05)×103/M for ephedrine and (3.80±0.02) ×103/M for pseudoephedrine, with the binding sites of (8.92±0.06) ×10−4 M. Thermodynamic studies showed that the binding of the two compounds to β2-AR was a spontaneous reaction with exothermal processes. The ΔGθ, ΔHθ and ΔSθ for the interaction between ephedrine and β2-AR were −(22.33±0.04) kJ/mol, −(6.51±0.69) kJ/mol and 50.94±0.31 J/mol·K, respectively. For the binding of pseudoephedrine to the receptor, these values were −(21.17±0.02) kJ/mol, −(7.48±0.56) kJ/mol and 44.13±0.01 J/mol·K. Electrostatic interaction proved to be the driving force during the binding of the two drugs to β2-AR. The proposed immobilised method will have great potential for attaching protein to solid substrates and realizing the interactions between proteins and drugs. [ABSTRACT FROM AUTHOR]

Self-competitive displacement is used to examine changes in the association constant and the binding site for berberine binding to immobilized β2-adrenoceptor (β2-AR) at different temperatures and using a varying mobile phase. The compound was confirmed to have a single kind of binding site to β2-AR under all the tested conditions. At 298.15 K, the association constant and the binding site are (2.12 ± 0.02) × 104 M−1and (1.56 ± 0.02) × 102 M. Thermodynamic investigation indicates that the binding of berberine to β2-AR has a positive change in energy due to enthalpy and negative response to entropy changes. Accordingly, this interaction is thought to be an endothermal process with entropy increase. The binding of berberine to the receptor was found to be more sensitive to ionic strength than pH. The placing of 1-propanol up to 5.0% in the mobile phases generates an 18% decrease in retention for berberine. These results indicate that the immobilized receptor would probably be an alternative for exploring the binding mechanism of ligand and receptor. [ABSTRACT FROM AUTHOR]

Because of the shortage of water source in the extreme arid area, generally, there are several years of no irrigation on mature shelterbelts. In this study, the shelterbelt soil in different texture were compared based on distribution analysis of the soil moisture and salt levels of shelterbelts under large-scale drip irrigation in Kalamiji Oasis in the lower reaches of Tarim River, Northwest China. The following conclusions were drawn. (1) In Kalamiji Oasis, the groundwater level declined at a rate of 0.5 m/a as a result of popularization of drip irrigation technology. (2) There was a larger heterogeneity in distribution for soil moisture in the sandy/loamy shelterbelt than in the clay shelterbelt. (3) Under non-irrigation conditions, sandy/loamy shelterbelt has lower soil moisture and salinity, and clay shelterbelt has higher soil moisture and salinity. (4) The shelterbelt with the shallowest groundwater depth had highest soil moisture level, and the shelterbelt with the deepest groundwater level had the lowest soil moisture content. (5) In sandy and loamy shelterbelts, the shelterbelts with the shallowest groundwater depths had the lower salinity levels and the shelterbelts with the deepest groundwater depths had the highest salinity levels. (6) In clay shelterbelts, the shelterbelts with the shallowest groundwater depths had the highest salinity levels, and the shelterbelts with the deepest groundwater depths had the lowest salinity levels. Additionally, it is essential to implement irrigation at least once a year. [ABSTRACT FROM AUTHOR]

This paper is based on long-term monitoring data for soil water, salt content, and groundwater characteristics taken from shelterbelts where there has been no irrigation for at least 5 years. This study investigated the distribution characteristics of soil water and salt content in soils with different textures. The relationships between soil moisture, soil salinity, and groundwater level were analyzed using 3 years of monitoring data from a typical oasis located in an extremely arid area in northwest China. The results showed that (1) the variation trend in soil moisture with soil depth in the shelterbelts varied depending on soil texture. The soil moisture was lower in sandy and loamy shelterbelts and higher in clay shelterbelts. (2) Salinity was higher (about 3.0 mS cm) in clay shelterbelts and lower (about 0.8 mS cm) in sandy shelterbelts. (3) There was a negative correlation between soil moisture in the shelterbelts and groundwater level. Soil moisture decreased gradually as the depth of groundwater table declined. (4) There was a positive correlation between soil salinity in the shelterbelts and the depth of groundwater table. Salinity increased gradually as groundwater levels declined. [ABSTRACT FROM AUTHOR]

Abstract: Fertilization (CK, N, P, K, NP, NK, PK, NPK) and watering (CK, rain, snow) were applied to a desert grassland of northwest Xinjiang, China. Results showed that: (1) After nutrient and water additions for one year, the plant community structure changed, the individual number of Graminoids increased significantly, while the individual number of Cruciferaes decreased sharply. The total species number was 16 before the treatment and 10 after the treatment, reduced by 37.5%. (2) The vegetation coverage above ground and the plant density increased significantly under the additions of NP and NPK (p < 0.05), while the other nutrient additions had no significant effects on the vegetation coverage and density. Neither additional snow addition nor rain had significant effects. (3) Compared with the control (CK), the additions of N, P and PK increased the diversity indexes (D &H′) and Evenness (J); the additions of K, NP, NK and NPK decreased the diversity indexes (D &H′) and evenness (J). However, neither of the treatments has significant effect on the diversity indexes and Evenness based on the ANOVA (p < 0.05). (4) Snow significantly decreased the plant species richness (p < 0.05). However, neither the rain nor the nutrient addition has significant effect on the species richness. (5) The inter-annual variation trend of the diversity indexes (D &H′) and Evenness (J) showed an increasing trend during 2009–2012. [Copyright &y& Elsevier]

For studying the effect of methanol gasoline on the corrosion and mechanical properties of rubber parts in vehicles, an immersion test of several currently used rubber parts in methanol gasoline is conducted to observe the variation relationship between the deformation and acting force of rubber parts and to analyze the cause of change of rubber parts after immersion. The results show that the black precipitate of solution, in which rubber parts are immersed, contains carbon black; the rubber tube made of NBR + CR or FKM + braided layer + ECO are rather significantly subjected to the effects of methanol concentration of methanol gasoline, leading to marked deterioration in mechanical performance; multi-layered PA12 is also greatly subjected to the effects of methanol but is not sensitive to the proportion of methanol added; while methanol has no apparent effects on the oil seals for intake and exhaust valves. [ABSTRACT FROM AUTHOR]

Abstract: we have obtained a high quality surface-enhanced Raman scattering (SERS) spectrum of m-hydroxybenzoic acid (MHBA) on the surfaces of silver nano-particles. In theoretical calculation, models of MHBA adsorbed on the surfaces of silver nano-particles were established and each of them corresponds to an experimental configuration. The Raman vibrational wavenumbers of these models using DFT-B3PW91 with lanl2dz were calculated; and it was compared with experimental spectrum. Analyzing the comparison of the results of theoretical calculation and experimental spectrum, we found out the actual configuration of MHBA on the surfaces of silver nano-particles. In our paper, we also prove that the simplified models are probably reasonable to describe some surface enhanced Raman experiments. [Copyright &y& Elsevier]

Abstract: A receptor affinity chromatographic selection method was developed for screening the bioactive compounds binding to β 2-adrenoceptor (β 2-AR) in Coptidis rhizome. The bioactive compounds were analyzed by molecular recognition with a β 2-AR affinity column. The retention compounds eluted from the β 2-AR column were separated online with reverse-phase high-performance liquid chromatography by column switching technology, and identified by a coupled ion-trap mass spectrometer. Four compounds were screened as the bioactive compounds of Coptidis rhizome and identified as 2,9,10-trimethoxy-3-hydroxyl-protoberberine (jateorhizine), 2,3-methylenedioxy-9-methoxy-protoberberine, 2,3,9,10-tetramethoxy-protoberberine (palmatine) and 2,3-methylenedioxy-9,10-dimethoxy-protoberberine (berberine). The association constants of jatrorrhizine, palmatine and berberine to the β 2-AR were determined by the zonal elution method with standards. Berberine and palmatine had only one type of binding site on the immobilized β 2-AR. Their association constants were (2.28±0.11)×104/M and (3.00±0.10)×104/M, respectively. Jatrorrhizine had at least two type of binding sites on the immobilized β 2-AR, and the corresponding association constants were (2.20±0.09)×10−4/M and (6.78±0.001)×105/M. [Copyright &y& Elsevier]

Abstract: Investigation of the interaction between drugs and receptors is very important in revealing the biologic basis and mechanism of the drug, and designing new bioactive compounds. The β 2-adrenoceptor (β 2-AR) was purified from rabbit lung tissues and immobilized on the surface of macro-pore silica gel through covalent bonds to prepare the stationary phase. Binding isotherms of terbutaline and salbutamol were determined by frontal analysis and the perturbation method, respectively. On the basis of the model of binding isotherm assumed, zonal elution was used to investigate the binding interaction of the receptor with terbutaline and salbutamol. The two drugs had one type of common binding site on immobilized β 2-AR. Salbutamol had at least one other major binding region. The association constant for terbutaline was (9.76±0.67)×104/M, and the concentration of the binding sites was (9.37±1.32)×10−6 M. Under identical conditions, association constants for salbutamol at the two types of binding site were (1.11±0.08)×104/M and (1.34±0.13)×103/M, and the concentration of the binding sites was (5.46±0.35)×10−6 M. Entropy increase was the main driving force for terbutaline and salbutamol to bind with β 2-AR. The associating reaction of terbutaline and β 2-AR was an exothermal process primarily from electrostatic interactions; hydrophobic force was the major factor contributing to the process for salbutamol. [Copyright &y& Elsevier]

Abstract: We studied the dependence of the Raman spectra on the concentration of PHBA aqueous solution under UV laser excitation. Through analyzing the spectra, we conclude that the interaction between PHBA ions and H2O molecules is weak. To further explore the problem, we studied the interaction between PHBA ions and H2O molecules by virtue of theoretical calculations, DFT-B3PW91/6-31+g* was employed. We draw a coincident conclusion with the experiments and dug out the reasonable interaction model that reflects the actual interaction configuration between PHBA ions and H2O molecules. We supply a new thinking for studying interactions between solute molecules and solvent molecules, which also can be applied to interactions between solute molecules and other solute molecules in solutions. [Copyright &y& Elsevier]

Objective. Our previous study found that it could significantly increase the expression of IL32 after stimulating the human umbilical cord mesenchymal stem cells (S-HuMSCs). However, its role on the osteogenesis and cranial bone regeneration is still largely unknown. Here, we investigated the possible mechanism of this effect. Material and Methods. A series of experiments, including single-cell sequencing, flow cytometry, quantitative real-time polymerase chain reaction, and western blotting, were carried out to evaluate the characteristic and adipogenic–osteogenic differentiation potential of IL-32 overexpression HuMSCs (IL-32highHuMSCs) through mediating the P38 signaling pathway. Moreover, a rat skull bone defect model was established and treated by directly injecting the IL-32highHuMSCs to conduct its role on the cranial bone regeneration. Results. In total, it found that compared to HuMSCs, IL32 was significantly increased and promoted the osteogenic differentiation (lower expressions of PPARγ, Adiponectin, and C/EBPα, and increased expressions of RUNX2, ALP, BMP2, OPN, SP7, OCN, and DLX5) in the S-HuMSCs (P < 0.05). Meanwhile, the enhanced osteogenic differentiation of HuMSCs was recovered by IL-32 overexpression (IL-32highHuMSCs) through activating the P38 signaling pathway, like as the S-HuMSCs (P < 0.05). However, the osteogenic differentiation potential of IL-32highHuMSCs was significantly reversed by the P38 signaling pathway inhibitor SB203580 (P < 0.05). Additionally, the HuMSCs, S-HuMSCs, and IL-32highHuMSCs all presented adipogenic–osteogenic differentiation potential, with higher levels of CD73, CD90, and CD105, and lower CD14, CD34, and CD45 (P > 0.05). Furthermore, these findings were confirmed by the rat skull bone defect model, in which the cranial bone regeneration was more pronounced in the IL-32highHuMSCs treated group compared to those in the HuMSCs group, with higher expressions of RUNX2, ALP, BMP2, and DLX5 (P < 0.05). Conclusion. We have confirmed that S-HuMSCs can enhance the osteogenesis and cranial bone regeneration through promoting IL-32-mediated P38 signaling pathway, which is proved that IL-32 may be a therapeutic target, or a biomarker for the treatment of cranial bone injuries. [ABSTRACT FROM AUTHOR]

The study of protein-drug interaction plays a crucial role in understanding drug mechanisms, identifying new drug targets and biomarkers, and facilitating drug development and disease treatment. In recent years, significant progress has been made in various protein-drug interaction research methods due to the rapid development and in-depth application of mass spectrometry, nuclear magnetic resonance, Raman spectroscopy, and other technologies. The progress has enhanced the sensitivity, precision, accuracy, and applicability of analytical methods, enabling the establishment of drug-protein interaction networks. This review discusses various emerging research methods, such as native mass spectrometry, infrared spectroscopy, nuclear magnetic resonance and spectrum, biosensor technologies employing surface enhanced Raman, electrochemistry, and magneto resistive signals, as well as affinity magnetic levitation and affinity chromatography. The article also delves into the principles, applications, advantages, and limitations of these technologies. • Up-to-date overview of emerging methods for protein-drug interactions. • Overview of the principles and applications of interaction methods based on different detection technologies. • Examination of advantages and disadvantages of each interaction method. • Future development direction for protein-drug interaction research. [ABSTRACT FROM AUTHOR]

Immobilized proteins hold promise as the basic units that have enabled a broad range of analytical applications within chemical measurement science. As yet, the co-immobilization of diverse proteins at precise ratio and whether they give rise to improved analytical performance remain challengeable. Herein, we utilized a circularly permuted HaloTag (cpHaloTag) to achieve the co-immobilization of two proteins at precise ratio, which was applied in developing a chromatographic method with improved specificity for pursuing dual-target compounds. The methodology involved the fusion 3A and 2C at N- and C-terminuses of cpHaloTag, the immobilization of the fusion protein onto silica gel through bioorthogonal reaction, the morphological and functional characterization, the application in finding dual-target compounds. Expression of the fusion protein in E. coli system showed a yield of milligram level with the presence of 3A and 2C domains. Immobilization of the protein was achieved in 10 min with a reaction efficiency more than 88.5 %. Immobilized 3A-cpHalo-2C exhibited higher specificity and better retentions of canonical compounds of the two enzymes in comparison with the column containing immobilized 3A or 2C alone. In real sample application, screening analysis found that hyperoside, cymaroside, and baicalin were dual-target compounds in concert with 3A and 2C in Shuanghuanglian extract. Taking 3A and 2C as probe, we proposed a simple method for direct co-immobilization of diverse proteins from cell lysates and demonstrated an affinity chromatographic-based dual-target compound screening platform. The implications of these methodology are possible to insight the de novo design of multi-target surface for fabricating new bioanalytical methods with improved performance. [Display omitted] • Proposed a strategy for co-immobilizing of 3A and 2C proteins at precise ratio. • Co-immobilized fusion protein by cpHaloTag improved chromatographic specificity. • Highly selective screening of dual-target compounds in natural products. [ABSTRACT FROM AUTHOR]

• The specific DNA aptamer of PPARγ was obtained by an on-column SELEX method. • PPARγ was immobilized by a bivalent affinity binding-inspired method. • Enhanced conformation selectivity and ligand-binding activity was found for PPARγ. Functional protein immobilization forms the basis for bio-detections. A series of one-point, site-specific immobilization methods have been developed, however, it still remains as a challenge how to avoid the proteins to move in all directions as well as conveniently regenerate the bio-devices. Herein, we have developed a bivalent affinity binding-inspired method for PPARγ immobilization using DNA aptamer and nickel-nitrilotriacetic acid (Ni2+-NTA) chelation. The specific DNA aptamer (Apt 2) was selected by an on-column systematic evolution of ligands by exponential enrichment (SELEX) method with affinity of (1.57 ± 0.15) × 105 M−1, determined by isothermal titration calorimetry (ITC). Apt 2 and nickel-nitrilotriacetic acid (Ni2+-NTA) were modified on macroporous silica gels via L-α-allylglycine as a linker. They respectively interacted with PPARγ and 6×His tag via bivalent affinity binding for the receptor immobilization. After comprehensive surface characterization, PPARγ was proved to be successful immobilized. Chromatographic studies revealed that the immobilized PPARγ has conformation selectivity, which discriminated agonist and antagonist of the receptor. Ligand-binding parameters (affinity and rate constant) of four agonists (rosiglitazone, pioglitazone, troglitazone, and magnolol) with PPARγ were determined. Troglitazone showed the lowest dissociation rate constant. The binding affinities (3.28 × 107, 1.91 × 106, 2.25 × 107, and 2.43 × 107 M−1) were highly consistent with the data obtained using purified receptor in solution (2.16 × 107, 4.52 × 106, 1.20 × 107, and 1.56 × 107 M−1), offering reliable bio-detection method for PPARγ and its ligands. Due to the biocompatibility of nuclear receptor with DNA, it is conceivable that the bivalent affinity-based method will be a general method for the immobilization of other nuclear receptors, which may provide selective conformation and improved ligand-binding activity for the receptors. [ABSTRACT FROM AUTHOR]

• Proposed a strategy for single-step purification and immobilization of GPCRs. • Immobilized GPCR by silica-binding peptide improved chromatographic performance. • Develop a surface-based binding assay with enhanced accuracy for determination. Protein functionalized surface has the potential to develop new assays for determining the drug-like properties of potential compounds and discovering specific partners of G protein-coupled receptors (GPCRs). However, a universal method for purifying and immobilizing functional GPCRs has remained elusive. To this end, we developed a general and rapid way to purify and immobilize β 2 -adrenergic receptor (β 2 AR) by silicon-specific peptide. We screened CotB1p as a tag from six silica-binding peptides (minTBP-1, CotB1p, SB 7 , Car 9 , and Si 4–1) by examining their affinity to macroporous silica gel. We investigated the adsorption and desorption of CotB1p-tagged β 2 -adrenoceptor (β 2 AR-CotB1p) under diverse conditions to propose a protocol for receptor purification and immobilization. Under optimized conditions, β 2 AR immobilization were achieved by directly immersing cell lysates harboring the receptor with silica gel, and the elution of the receptor without demonstratable contaminants was realized by including l-arginine/L-lysine in the elutes. This allows purification of the receptor from Escherichia coli (E.coli) lysates with a purity of 95 %. The immobilized receptor was utilized as a stationary phase to reveal the tag impact on ligand-binding outputs by comparing the CotB1p-strategy with a typical covalent method. The K A s of salbutamol, chlorprenaline, tulobuterol, and terbutaline on β 2 AR-CotB1p column were 1.26 × 106, 6.59 × 106, 7.90 × 106, and 8.97 × 105 M−1 respectively, which were two orders of magnitude higher than those on the Halo-β 2 AR column. The whole immobilization was accomplished within 30 min without the requirement of any special treatment, resulting in enhanced accuracy for determining receptor-ligand binding parameters. Taken together, CotB1p-mediated strategy is simple, rapid, and universal for purification or immobilization of unstable biomolecules like GPCRs for analytical and biological applications. [ABSTRACT FROM AUTHOR]

• Stationary phase was prepared through enzymatic DNA-protein conjugation strategy;. • CysLTR1 was immobilized in a site-specific, one-step, and covalent fashion;. • Ligand-binding activity and lead screening were achieved by immobilized CysLTR1. Immobilization of functional protein, especially G protein-coupled receptors (GPCRs), is particularly significant in various fields such as the development of assays for diagnosis, lead compound screening, as well as drug-protein interaction analysis. However, there are still some challenges with the immobilized proteins such as undefined loads, orientations, and the loss of activity. Herein, we introduced a DNA conjugation strategy into the immobilization of Cysteinyl leukotriene receptor 1(CysLTR1) which enables exquisite molecular control and higher activity of the receptor. We used the bacterial relaxases VirD2 as an immobilized tag fused at the C terminus of CysLTR1. Tyrosine residue(Y29) at the core binding site of the VirD2 tag can react with the single-strand piece of DNA(T-DNA) in the form of a covalent bond. Inspired by this strategy, we developed a new immobilization method by mixing the T-DNA-modified silica gel with the cell lysate containing the expressed VirD2-tagged CysLTR1 for 1 hour. We found that the successful formation of DNA-protein conjugate enables the immobilization of CysLTR1 fast, site-specific, and with minimal loss of activity. The feasibility of the immobilized CysLTR1 was evaluated in drug-protein binding interaction by frontal analysis and adsorption energy distribution analysis. The binding of pranlukast, zafirlukast, and MK571 to the immobilized CysLTR1 was realized, and the association constants presented good agreement between the two methods. Rosmarinic acid was retained in the immobilized CysLTR1 column, and the in-vitro test revealed that the compound binds to the receptor in one type of binding site mode. Despite these results, we concluded that the DNA-protein conjugate strategy will probably open up the possibilities for capturing other functional proteins in covalent and site-specific modes from the complex matrices and the immobilized receptor preserves the potential in fishing out lead compounds from natural products. [ABSTRACT FROM AUTHOR]

The quality control process for sintered ore is cumbersome and time- and money-consuming. When the assay results come out and the ratios are found to be faulty, the ratios cannot be changed in time, which will produce sintered ore of substandard quality, resulting in a waste of resources and environmental pollution. For the problem of lagging sinter detection results, Long Short-Term Memory and Genetic Algorithm-Recurrent Neural Networks prediction algorithms were used for comparative analysis, and the article used GA-RNN quality prediction model for prediction. Through correlation analysis, the chemical composition of the sintered raw material was determined as the input parameter and the physical and metallurgical properties of the sintered ore were determined as the output parameters, thus successfully establishing a GA-RNN-based sinter quality prediction model. Based on 150 sets of original data, 105 sets of data were selected as the training sample set and 45 sets of data were selected as the test sample set. The results obtained were compared to the real value with an average prediction error of 1.24% for the drum index, 0.92% for the low-temperature reduction chalking index (RDI), 0.95% for the reduction index (RI), 0.40% for the load softening temperature T10%, and 0.43% for the load softening temperature T40%, with all within the running time thresholds. The study of this model enables the prediction of the quality of sintered ore prior to sintering, thus improving the yield of sintered ore, increasing corporate efficiency, saving energy, and reducing environmental pollution. [ABSTRACT FROM AUTHOR]

• Heptapeptide of β 2 -AR recognizes ephedrine and pseudoephedrine epimers in solution. • Immobilized peptide separates the epimers in herbal extract and blood samples. • An enhanced hydrogen bonding was found in heptapeptide-pseudoephedrine complex. Epimer separation is crucial in the field of analytical chemistry, separation science, and the pharmaceutical industry. No reported methods could separate simultaneously epimers or even isomers and remove other unwanted, co-existing, interfering substances from complex systems like herbal extracts. Herein, we prepared a heptapeptide-modified stationary phase for the separation of 1R,2S -(-)-ephedrine [(-)-Ephe] and 1S,2S -(+)-pseudoephedrine [(+)-Pse] epimers from Ephedra sinica Stapf extract and blood samples. The heptapeptide stationary phase was comprehensively characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The separation efficiency of the heptapeptide column was compared with an affinity column packed with full-length β 2 -AR functionalized silica gel (β 2 -AR column). The binding affinity of the heptapeptide with (+)-Pse was 3-fold greater than that with (-)-Ephe. Their binding mechanisms were extensively characterized by chromatographic analysis, ultraviolet spectra, circular dichroism analysis, isothermal titration calorimetry, and molecule docking. An enhanced hydrogen bonding was clearly observed in the heptapeptide-(+)-Pse complex. Such results demonstrated that the heptapeptide can recognize (+)-Pse and (-)-Ephe epimers in a complex system. This work, we believe, was the first report to simultaneously separate epimers and remove non-specific interfering substances from complex samples. The method was potentially applicable to more challenging sample separation, such as chiral separation from complex systems. [ABSTRACT FROM AUTHOR]

• Field data showed groundwater salinity increase after beach nourishment. • Beach nourishment of heterogeneous aquifers creates complex fresh-saline interface movement. • Beach nourishment can merge layered heterogeneity and cause severe groundwater salinization. Beach nourishment is a widespread coastal management technique, which can not only counteract coastal erosion, but also changes coastal groundwater dynamics. Understanding mechanisms and drivers of this subsurface flow and transport processes is key to predicting future groundwater resources to beach nourishment. We implemented a monitoring network of specific conductivity (SC) sensors in wells at different aquifers layers before and after beach nourishment. Recorded SC show that groundwater salinity increased differently after beach nourishment at multiple depths. We used a series of variable-density groundwater flow and salt transport models with both homogeneous and layered heterogeneous cases to illustrate characteristics of groundwater salinity after beach nourishments. Simulations showed that in homogeneous aquifers, salinization patterns were simple and linear related to the beach depth and width, with a relief effect on seawater intrusion. In heterogeneous aquifers, salinity patterns were much more complicated, and the resulting effects on seawater intrusion were determined by the breakdown of original layered system. The analysis provides new insights into the effect of beach nourishment on seawater intrusion. Consideration of aquifer heterogeneity can be a starting point for more sophisticated groundwater management, including vulnerability assessment and optimization of beach nourishment. [ABSTRACT FROM AUTHOR]

The feasibility of immobilized protein-based biodetection relies critically on the activity of the immobilized proteins as well as the biocompatibility of the protein surface. Although many protein immobilization strategies have been developed with satisfied detection readout signals. Non-specific interactions caused by the protein-coating surface are still of great concern since they often interfere with or affect the reliability of detection. Herein, we developed a highly efficient G protein-coupled receptor (GPCR) immobilization method by the combination of polyethylene glycol (PEG) with a self-labeling enzyme-catalyzed reaction. The immobilization relies on the covalent interaction between the fusion tag of a target GPCR (kinase domain of epidermal growth factor receptor, EGFR) and its covalent inhibitor ibrutinib, which is modified on PEGylated silica gels. Two types of GPCRs, N-methyl-D-aspartate 2 A receptor (NMDAR 2A) and endothelin A receptor (ET A R), were used as examples to realize protein immobilization. The GPCR modified gels and the affinity columns packed with them have been extensively characterized, in terms of non-specific adsorptions, retention factor (k ′), half peak width (W 1/2), tailing factor (T f), theoretical plates (N), and association and dissociation constants of the ligands with the receptors. The immobilized GPCRs with reduced non-specific interactions and enhanced fouling resistance, salt tolerance, and chromatographic performance were clearly observed. We believe it is the first work to introduce PEGylation in GPCR immobilization and provide comprehensive proof-of-concept studies to illustrate the improved antifouling property, salt tolerance, and chromatographic performance. This method could be generally applicable in other immobilized protein-based technology for reliable biodetection. [Display omitted] • We developed a highly efficient GPCR immobilization method based on PEGylation. • Two types of GPCRs, NMDAR 2A and ET A R were applied to analyze the improvement of PEGylation. • PEGylated GPCR columns exhibited improved fouling resistance, salt tolerance, and chromatographic performance. • PEGylation provided more reliable measurements for the receptor-ligand interaction analysis. [ABSTRACT FROM AUTHOR]

• Proposed a label-free strategy for immobilizing GPCR using genetically encoded nnAAs. • Immobilized 5-HT 1A R O-ALTyr improved chromatographic performance. • High selective screening for 5-HT 1A R ligands in natural products. • Confirmed magnoflorine as a potential 5-HT 1A R agonist. G protein-coupled receptors (GPCRs) are one of the most prominent targets for drug discovery. Immobilizing GPCRs has proven to be an effective strategy for expanding the utility of GPCRs into nonbiological contexts. However, traditional strategies of immobilizing GPCRs have been severely challenged due to the loss of receptor function. Here, we reported a novel and general approach to realize the label-free and site-selective immobilization of 5-hydroxytryptamine 1A receptor (5-HT 1A R) and the application in developing a chromatographic method with improved specificity for pursuing 5-HT 1A R ligands from natural products. This method involved the use of a clickable non-natural amino acid, O-allyl-L-tyrosine (O-ALTyr) to immobilize the receptor onto thiol-functionalized silica gels through a 'thiol-ene' click chemistry, which allowed us to avoid the purification step and directly immobilize 5-HT 1A R on silica gels. The immobilized receptor was characterized using immunofluorescence assay, and receptor-ligand interaction analysis was conducted through frontal analysis. To test the feasibility of the immobilized 5-HT 1A R O-ALTyr in complex matrices, bioactive compounds in Ziziphi Spinosae Semen (ZSS) were screened and their interaction with the receptor was assessed using zonal elution. Our findings indicated that immobilizing the receptor through nnAAs effectively minimizes the chromatographic peak tailing and broadening of specific ligands, leading to a significant improvement in chromatographic performance. The association constants of the three ligands to 5-HT 1A R were approximately one order of magnitude greater than those of Halo-tag attachment. These results demonstrated that the immobilized 5-HT 1A R exhibits high specificity and the ability to recognize receptor ligands from complex matrices. This allowed us to identify magnoflorine (Mag) as a potential ligand of 5-HT 1A R from ZSS extract. In vivo assay also proved that Mag presented a promising anxiolytic effect by promoting the expression of 5-HT 1A R in mice brain. The above findings pointed to the fact that the immobilized 5-HT 1A R affinity chromatographic strategy relying on the site-specific encoded non-natural amino acid is a powerful alternative for precisely determining the drug-protein interaction and discovering the specific ligand of GPCRs from complex matrixes. [ABSTRACT FROM AUTHOR]

• Two receptors were co-immobilized in equimolar amounts by bioorthogonal reaction. • Equations for revealing drug-dual target binding on heterogeneous surface were derived. • The method is reliable, time- and ligand-efficient with improved throughput. Characterization of the drug-target interactions is pivotal throughout the whole procedure of drug development. Most of the current assays, particularly, chromatographic methods lack the capacity to reveal drug adsorption on the muti-target surface. To this end, we derived a reliable and workable mathematical equation for revealing drug bindings to dual targets on the heterogeneous surface starting from the mass balance equation. The derivatization relied on the correlation of drug injection amounts with their retention factors. Experimental validation was performed by determining the binding parameters of three canonical drugs on a heterogeneous surface, which was fabricated by fusing angiotensin receptor type I and type II receptors (AT 1 R and AT 2 R) at the terminuses of circularly permuted HaloTag (cpHaloTag) and immobilizing the whole fusion protein onto 6-bromohexanoic acid modified silica gel. We proved that immobilized AT 1 R-cpHalo-AT 2 R maintained the original ligand- and antibody-binding activities of the two receptors in three weeks. The association constants of valsartan, candesartan, and telmisartan to AT 1 R were (6.26±0.14) × 105, (9.66±0.71) × 105, and (3.17±0.03) × 105 L/mol. In the same column, their association constants to AT 2 R were (1.25±0.04) × 104, (2.30±0.08) × 104, and (8.51±0.06) × 103 L/mol. The patterns of the association constants to AT 1 R/AT 2 R (candesartan>valsartan>telmisartan) were in good line with the data by performing nonlinear chromatography on control columns containing immobilized AT 1 R or AT 2 R alone. This provided proof of the fact that the derivatization allowed the determination of drug bindings on the heterogeneous surface with the utilization of a single series of injections and linear regression. We reasoned that is simple enough to model the bindings of drug adsorption on commercially available adsorbents in fundamental or industrial fields, thus having the potential to become a universal method for analyzing the bindings of a drug to the heterogeneous surface containing multiple targets. [ABSTRACT FROM AUTHOR]

• The environmental problems created by mining activities in the arid region of China have not been addressed. • Land degradation is the most prominent problem resulting in mining activities. • Unclear objectives of ecological restoration is the main challenges faced by mining area. • Ideal restoration effects can be achieved through improvement of vegetation coverage and ecosystem services. The arid region in China with rich mineral resources are belongs to ecological fragile region with inadequate recovering capacity. Hundred years of continues mining of mineral resources for economic purposes, leads to the problem of land degradation caused by the spatial coupling of large-scale mining disturbance and arid fragile ecological environment. The environmental problems created by mining have not been addressed promptly, while at the same time, new problems have emerged. On the basis of our 20 years of practical experience on ecological restoration in mining areas, review and synthesis of selective literature, with interpretation and perspective, the mining situation and its ecological impacts, the factors impeding ecological restoration capability in the arid region in China were examined, the key challenges and promotion strategy were presented. The main findings of this study are as follows: Land degradation is the most prominent problem resulting in mining activities, and mainly reflected by immediate disturbance, long term effects and ecological degradation. The main challenges faced by mining area restoration in arid areas are unclear objectives of ecological restoration, lack of ecological water consumption, unreasonable selection of indigenous plants, serious land degradation and wide restoration area. Our restoration experiments in typical mining areas have proved that the micro-topography reconstruction measures can increase surface roughness, redistribute limited precipitation resources (especially snow), and make soil water and nutrients carried by surface runoff and collected in valleys to regulate soil infiltration and water supply, so as to achieve water-saving and non-irrigated vegetation restoration. The ideal restoration effects are the improvement of vegetation coverage, the increase of available land resources, and the improvement of ecosystem services in mining areas. This study would be helpful to carried out related implementation on ecological restoration and could act as a valuable reference for the researchers involved in the ecological restoration in arid region. [ABSTRACT FROM AUTHOR]

Abstract The pursuit of drugs having improved therapeutic efficacy necessitates increasing research on new assays for screening bioactive compounds with multi-targets. This work synthesized a chromatographic stationary phase containing co-immobilized beta 2 -adrenergic receptor (β 2 -AR) and voltage dependent anion channel isoform 1 (VDAC-1) to achieve such purpose. Specific ligands of the two receptors (e.g. salbutamol, methoxyphenamine, ATP and NADH) were utilized to characterize the specificity and bioactivity of the column. Validated application of the stationary phase was performed by screening multi-target compounds of Rhodiola crenulata using high performance affinity chromatography coupled with ESI-Q-TOF-MS. By zonal elution, we identified salidroside as a bioactive compound simultaneously binding to β 2 -AR and VDAC-1. The compound exhibited the binding sites of 1.0 × 10−7 and 4.0 × 10−7 M on the β 2 -AR and VDAC-1. On these sites, the association constants were calculated to be 3.3 × 104 and 1.0 × 104 M−1. Molecular docking indicated that the binding of salidroside to the two receptors occurred on Ser169 and Phe255of β 2 -AR, and the channel wall of VDAC-1. Taking together, we concluded that the column containing co-immobilized receptors has potential for screening bioactive compounds with multi-targets from complex matrices including traditional Chinese medicines. Highlights • A method was developed for screening bioactive compounds with multiple targets from Rhodiola creulata. • The method was validated and provided a high throughput screening strategy in a complex system. • Our study benefits from multi-targeting recognition, online separation and MS identification with a high sensitivity. [ABSTRACT FROM AUTHOR]