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In recent years, infrared thermographic (IRT) technology has experienced notable advancements and found widespread applications in various fields, such as renewable industry, electronic industry, construction, aviation, and healthcare. IRT technology is used for defect detection due to its non-contact, efficient, and high-resolution methods, which enhance product quality and reliability. This review offers an overview of active IRT principles. It comprehensively examines four categories based on the type of heat sources employed: pulsed thermography (PT), lock-in thermography (LT), ultrasonically stimulated vibration thermography (UVT), and eddy current thermography (ECT). Furthermore, the review explores the application of IRT imaging in the renewable energy sector, with a specific focus on the photovoltaic (PV) industry. The integration of IRT imaging and deep learning techniques presents an efficient and highly accurate solution for detecting defects in PV panels, playing a critical role in monitoring and maintaining PV energy systems. In addition, the application of infrared thermal imaging technology in electronic industry is reviewed. In the development and manufacturing of electronic products, IRT imaging is used to assess the performance and thermal characteristics of circuit boards. It aids in detecting potential material and manufacturing defects, ensuring product quality. Furthermore, the research discusses algorithmic detection for PV panels, the excitation sources used in electronic industry inspections, and infrared wavelengths. Finally, the review analyzes the advantages and challenges of IRT imaging concerning excitation sources, the PV industry, the electronics industry, and artificial intelligence (AI). It provides insights into critical issues requiring attention in future research endeavors. [ABSTRACT FROM AUTHOR]

The moisture content was a key factor affecting the permeability of the sintering granulation and the bed layer, and it promoted denitrification and combustion. This study investigated the influence of moisture content on denitrification, bed permeability, and the emissions of O2 and CO in the sintering process through industrial trials on-site. By analyzing sintering reaction mechanisms and SPSS data, and combining CHEMKIN simulation, the mechanism of moisture content on NO emissions during sintering was obtained. The results showed that the moisture content of the sintering mixture could affect the emission of NO in the sintering flue gas by influencing the permeability of the bed and the O2 and CO in the flue gas. As the moisture content of the mixture increased, the NO content in the sintering flue gas first decreased and then increased, while the permeability and CO content showed an initial increase followed by a decrease, and the volume fraction of O2 in the flue gas gradually decreased. Eight factors, including permeability index, O2 concentration, CO concentration, negative pressure, water vapor volume fraction, flue gas temperature, sintering trolley speed, and dust concentration, were significantly correlated with NO emissions, and a generalized linear model with NO emissions as the dependent variable was established. For a specific sintering industrial production, the moisture content of the sintering mixture determined the permeability. Apart from O2 concentration, permeability had the greatest impact and was negatively correlated with NO emissions. Water vapor in the flue gas could promote the CO-NO reaction, and the higher the water vapor volume fraction, the higher the reduction rate of NO, but excessively high levels were detrimental to permeability. Taking into account the permeability of the sintering bed, O2 and CO in the flue gas, the optimal moisture content (mass fraction) of the sintering mixture for denitrification during the sintering process ranged between 6.71% and 8.04%. In actual industrial sintering production, a water vapor volume fraction in the flue gas between 16% and 18% was most favorable for denitrification during the sintering process. These findings provided theoretical references for denitrification processes during sintering. [ABSTRACT FROM AUTHOR]

• Answered the question of " Whether the ecological benefits will continue to improve as usual under the background of continuous ecological water convey?" • Answered the question of " How wide is the impact of ecological water convey on groundwater and the vegetation in riparian zone?" • Answered the question of " Where ecological water has been consumed at different times?" In arid regions, ecological water replenishment benefits in desert riparian forests are typically evaluated by assessing changes in hydrology (water area and groundwater depth) and vegetation growth before and after it is implemented. While continuous ecological water delivery may enhance ecological benefits, its trajectory remains uncertain. Under the backdrop of ongoing ecological water delivery, this study examines whether ecological benefits continue to improve and identifies strategies for optimal control and efficient utilization of ecological water. Based on an analysis of groundwater level changes and vegetation changes during early, middle, and late stages of ecological water conveyance in the Tarim River, China (2000–2021), ecological water consumption distribution was revealed. A notable observation is that a wide eco-water conveyance did not significantly impact forest growth indicators, such as tree ring density, crown width, and tree ring size, in Populus euphratica trees. Compared to a century ago, there were significant variations in the growth of P. euphratica tree rings over the 20-year ecological water transfer period. The vegetation coverage on riverbanks increased significantly in the early to mid-stages of ecological water conveyance (2000–2015), but then plateaued in the subsequent years (post-2015). There was a significant upward trend in plant diversity on riverbanks and tail lakes during the early stage (2000–2006), but it declined sharply thereafter (post-2006). A recommendation includes constraining the tail lake's water area and using ecological sluice gates and levees to disperse eco-water away from the river to enhance the efficiency of ecological water utilization. As a result of these findings, rational management systems can be developed in similar arid environments. [ABSTRACT FROM AUTHOR]

The tree ring is an important carrier of the evolution of climate in the study of global change. It enjoys advantages of accurate dating, strong continuity, high resolution ratio and high reconstruction precision. This paper tested the changes of Populus euphratica tree ring and the runoff in the upper and middle reaches of the Tarim River through the monotonic trend and analyzed the response of the tree ring in the lower reaches of the Tarim River to the water supply through the combined tree ring data and the historical literature, so as to confirm the accuracy of the response of Populus euphratica tree ring to river diversion. The results were included as follows. (1) From 1957 to 2010, the radial growth of Populus euphratica in the upper and middle reaches of the Tarim River decreased gradually in the time series, which was the same as the runoff. The downtrend was significant, and | Zc | was more than 0.96. (2) From 1913 to 2000, the radial growth of Populus euphratica as a whole in the lower reaches of the Tarim River decreased. The downtrend was significant between 1973 and 2001, reaching the lowest level in the past 100 years. The formation and diversion of the Layi River was as described in the historical literature. (3) The development of the ecological water delivery project has improved the ecological environment of the lower reaches, which has been verified from the Populus euphratica tree ring in the lower reaches. However, despite the ecological water delivery project in recent years, the growth of Populus euphratica tree ring has not reached to the level before 1920, indicating that the existing ecological water delivery is of limited value in recovering desert riparian forest (4) In the analysis of the response of the Populus euphratica to the water resources, the wavelet analysis method and the historical literature review method have drawn the same conclusion. [ABSTRACT FROM AUTHOR]

Studies on the interactions between urban landscape patterns and land surface temperatures are the key to urban heat island (UHI) mitigation. However, the landscape pattern indices used in previous studies were inconsistent in type and number. Furthermore, few studies combined the composition and configuration indices into one integrated indicator. The description of landscape pattern is thus a great yet rewarding challenge. In this study, we used the integrated location weighted landscape index (LWLI) proposed by Chen et al. (2009) and revised it to indicate potential UHIs. Fifty-six circular landscape samples along four transects were created and the LWLI was derived based on the theory of the GINI index. The LWLI considers the type, composition and configuration of different land covers inside a landscape, where configuration is treated as location weights. The potential UHI was represented by the land surface temperature (LST) of each circle landscape center. The correlation analysis results showed that the LWLI was significantly positively correlated with summer potential UHIs, with a Pearson R equaling 0.736, and barely correlated with winter potential UHI. Moreover, the LWLI was slightly more strongly correlated with potential UHI than composition alone. These correlations weakened as the landscapes grew larger. The linear regression results further revealed that the LWLI explained about 53% of the summer potential UHI, which was slightly better than composition alone (49%). This indicated that the LWLI was as effective in predicting the potential UHI as the combination of several pattern indicators, echoing Tobler’s first law of geography, which states that “all things are related, but nearby things are more related than distant things.” This study also leaves room for improvement of the index by integrating more environmental/ecological parameters as weights, and for further application of the index in other fields. [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]

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]

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]

Drinking water samples (N = 228) from domestic tube wells (DTWs) and seven samples from public water supply wells (PWSWs)were collected and tested in Hailun, northeast China. The percentage of samples with nitrate and ammonia concentrations above the maximum acceptable concentration of nitrate, 10 mg N/L, and the maximum ensure concentration of ammonia, 1.5 mg/L, for the DTWs were significantly higher than for the PWSWs. Of the DTWs, an important observation was that the occurrence of groundwater nitrate contamination was directly related to well tube material with different joint pathways. Nitrate in seamless-tube wells was lower statistically significantly than those in multiple-section tube wells (p < .001). Furthermore, well depth and hydrogeological setting might have some impacts on nitrogen contamination and the major sources of inorganic nitrogen contamination may be nitrogenous chemical fertilizer. Therefore, PWSWs built for all families are the best way to ensure the drinking water safety in villages. For DTWs it is necessary to use seamless tubes and to dig deep enough according to the depth of groundwater level. Improving the efficiency of chemical fertilizer use would also reduce the risk of groundwater contamination. [ABSTRACT FROM AUTHOR]

Abstract: Demand on high-throughput methods for multi-target compounds screening continues to increase nowadays due to the decline of new drugs on the market. Two kinds of G-protein-coupled receptors, alpha1-adrenoceptor (α 1A-AR) and beta2-adrenoceptor (β 2-AR), were purified and immobilized on the surface of macroporous silica gel to prepare new chromatographic stationary phases. Control drugs (e.g., prazosin, terazosin, salbutamol, and terbutaline) were used to characterize the retention behavior of the obtained α 1A-AR and β 2-AR columns. This study also coupled both columns with a six-way switching valve to construct an automatic two-dimensional system for multi-target compounds screening in complex mixtures. Adrenaline hydrochloride was used as a representative drug to evaluate the chromatographic performance of the two dimensional system. The aqueous extracts from Salvia miltiorrhiza and Coptis chinensis were also analyzed by the automatic system. The compounds in S. miltiorrhiza had no binding to both α 1A-AR and β 2-AR columns. But berberine, palmatine and jatrorrhizine were screened as the bioactive compounds in C. chinensis, targeting both the receptors. The proposed method is an alternative for recognizing and separating the compounds targeting different proteins from a complex matrix. [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]

β2-Adrenoceptor (β2-AR) was purified from the rabbit lung tissue by sepharose-salbutamol affinity chromatographic column. To prepare the β2-AR stationary phase, β2-AR was evenly immobilized on the surface of macro-pore silica with a mild chemical coupling method through covalent bond. The retention properties of β2-AR stationary phase were characterized by four ligands, salbutamol sulfate, noradrenaline bitartrate, adrenaline hydrochloride and propranolol hydrochloride, to establish the β2-AR affinity chromatography. Then, the method was used to screen the active compounds from the total extracts of Semen Armeniacae Amarum. The results showed that β2-AR on the surface of the stationary phase could keep its original bioactivity and selectivity. Amygdalin retained in the chromatographic column was proved to be the active compound of the total extracts of Semen Armeniacae Amarum. Compared with the existing chromatographic screening approaches, this method showed a good stability and high selectivity. The active compounds which could interact with β2-AR in traditional Chinese medicine (TCM) could be screened efficiently by this method, providing a new way to screen the active compounds in complicated samples such as TCM. [ABSTRACT FROM AUTHOR]

Abstract: A micellar electrokinetic chromatography (MEKC) method for the simultaneous determination of four bioactive constituents (morroniside, loganin, paeoniflorin and paeonal) in the Chinese patent medicine Liuwei Dihuang Pills is established. A carrier composed of 0.2M boric acid, 0.02M sodium dodecyl sulfate (SDS) and 5% acetonitrile (pH was adjusted to 10.5 with 0.1M NaOH) is found to be the most suitable electrolyte for this separation. The four constituents in Liuwei Dihuang Pills can be easily determined within 16min. Optimization of separation is realized with the univariate approach by studying the effects of four factors relevant to run buffer on migration times. [Copyright &y& Elsevier]

Gallic acid (GA), one of the bioactive compounds in Choerospondiatis fructus, was determined in rabbit plasma. The method involved a protein precipitation, a high performance liquid chromatographic separation, and an electrospray ionization ion trap mass spectrometric determination. Plasma samples were extracted by 0.5 mL 1.5% phosphoric acid/acetonitrile(v/v). Chromatographic separation was achieved on a C18 column using a mobile phase of 5.0% acetonitrile/water with 0.2% formic acid (pH 2.2). The calibration curve was linear in the range of 0.5–400 ng · mL-1 for plasma samples. The limit of detection was 200 pg · mL-1. Intra‐and inter‐day coefficients of variation were less than 8.0% and intra‐ and inter‐day accuracies were within ±5.0% of the known concentrations. Finally, this assay was used to study the pharmacokinetics of GA in rabbit plasma following ingestion of Choerospondiatis fructus extracts. The statistical results indicated that the plasma drug concentration time course in rabbit was a 2‐compartment open model. [ABSTRACT FROM AUTHOR]

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]

Abstract: We have obtained a Raman spectrum of BA on TLCSS coated with silver nanoparticles. In theoretical calculation, models of benzoic acid (BA) adsorbed on the surfaces of silver nanoparticles 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 dug out the actual experimental configuration of benzoic acid (BA) adsorbed on the surfaces of silver nanoparticles. The calculations of binding energy also were employed to explain this problem. 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 high quality Raman spectrum of p-hydroxybenzoic acid (PHBA) aqueous solution (10−2 M) under ultraviolet (UV) excitation at 325nm was obtained, which could not be observed with visible and near infrared (NIR) excitations due to the low concentration in aqueous solution. Theoretical calculated Raman frequencies based on density functional theory (DFT) reveals well the states of PHBA in aqueous solution. We supply a new method for studying the behaviors of materials in solution. [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]

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]

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]

Purposes: To investigate whether valproic acid (VPA) has a neuroprotective effect against ischemia/reperfusion (I/R) injury in the rat retina, and to elucidate the potential antioxidant mechanisms involved. Methods: Adult male Wistar rats were randomly divided into four groups: sham (group A), sham plus VPA (group B), I/R plus vehicle (group C), and I/R plus VPA (group D). Retinal I/R injury was produced by inducing an exceedingly high intraocular pressure (IOP). Prior to insult, VPA was administered subcutaneously (300 mg/kg twice daily) for 7 days, after which the animal was sacrificed. Levels of retinal malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were determined. Protein expressions of retinal poly(ADP-ribose) (PAR) and nitrotyrosine (NT) were analyzed by Western blotting 24 h after injury. Apoptosis of retinal cells was evaluated 24 h after I/R injury by immunofluorescence of activated caspase-3 in histological sections of retina. Seven days after reperfusion, electroretinography (ERG) was performed, and retinal histological changes were examined by light microscopy. Results: Following ischemia, the thickness of the entire retina, including the inner nuclear layer (INL) and inner plexiform layer (IPL), as well as the number of cells in the ganglion cell layer (GCL) were significantly greater in group D than in group C ( p < 0.05). VPA suppressed I/R-induced reductions in ERG a- and b-wave amplitudes ( p < 0.05). VPA attenuated I/R-induced activation of caspase-3 in ganglion cells and INL cells ( p < 0.001). VPA significantly decreased MDA levels and increased activities of SOD, GSH-Px, and CAT in group D ( p < 0.05). VPA attenuated activation of PAR and accumulation of NT in the retina after I/R ( p < 0.01). Conclusions: VPA protects the retina from I/R injury by enhancing anti-oxidative effects and inhibiting apoptosis of retinal cells. [ABSTRACT FROM AUTHOR]

The identification of bioactive compounds in complex matrices remains a major challenge due to the lack of highly efficient and specific methods. This work developed an approach based on high‐performance affinity chromatography to identify the potential antitussive compounds from Zhisou oral liquid. The main methods include the synthesis of immobilized beta2‐adrenoceptor by a one‐step method, the screening and identification of the potential bioactive compounds by the receptor column coupled with mass spectrometry, and the binding mechanism analysis of the compounds to the receptor by the in vivo experiment, injection amount dependent method and molecular simulation. We identified the potential bioactive compounds of Zhisou oral liquid as glycyrrhizic acid, platycodin D, tuberostemonine, and hesperidin. In vivo experiment showed that the combinational utilization of the four compounds was possible to present an equivalent antitussive effect to the formula. The docking results demonstrated that hydrogen bonds and Van der Waals forces were the main forces to drive the binding of the four compounds to beta2‐adrenoceptor. We concluded that the four compounds are the effective components in Zhisou oral liquid. The proposed strategy is possible to provide an alternative for the development of highly efficient methods to pursue the bioactive compounds of complex matrices. [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]

Abstract Human and animal studies have shown that the colonic concentrations of lipid peroxidation products, such as 4-hydroxynonenal (4-HNE), are elevated in inflammatory bowel disease (IBD). However, the actions and mechanisms of these compounds on the development of IBD are unknown. Here, we show that a systemic treatment of low-dose 4-HNE exacerbates dextran sulfate sodium (DSS)-induced IBD in C57BL/6 mice, suggesting its pro-IBD actions in vivo. Treatment with 4-HNE suppressed colonic expressions of tight-junction protein occludin, impaired intestinal barrier function, enhanced translocation of lipopolysaccharide (LPS) and bacterial products from the gut into systemic circulation, leading to increased activation of Toll-like receptor 4 (TLR4) signaling in vivo. Furthermore, 4-HNE failed to promote DSS-induced IBD in Tlr4 -/- mice, supporting that TLR4 signaling contributes to the pro-IBD effects of 4-HNE. Together, these results suggest that 4-HNE exacerbates the progression of IBD through activation of TLR4 signaling, and therefore could contribute to the pathogenesis of IBD. Graphical abstract fx1 Highlights • 4-hydroxynonenal (4-HNE) exaggerates colonic inflammation in mice. • 4-HNE increases concentrations of LPS and bacterial products in the circulation, leading to enhanced activation of TLR4 signaling in vivo. • The pro-inflammatory effects of 4-HNE were abolished in Tlr4 -/- mice. [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]

Sulfates produced by the reaction of metal oxides in coal ash with the acid gases in the atmosphere are the main causes of haze-fog formation. In this study, laser induced breakdown spectroscopy(LIBS) was used for elemental analysis in coal ash. A new method was adopted to conduct an accurate qualitative analysis of the four elements (Al, Ca, Cu and Fe) that easily form sulfates in coal ash. An internal standard method was used to quantitatively analyze the typical Fe element of the four elements with a calibration curve that had a linear correlation coefficient (R 2 ) of 0.986. In order to test the accuracy of the curve, three kinds of coal ash with unknown composition were selected and analyzed by LIBS and X-ray fluorescence spectrometry (XRF). The relative differences of the two methods were around 7.42%, 3.37% and 4.34%, respectively, which are all in the acceptable range. The experimental results indicate that LIBS can be employed for the rapid detection and analysis of metal elements in coal ash and provide a new classification method for coal ash based on the content of Fe element. [ABSTRACT FROM AUTHOR]

Investigations of drug-protein interactions have advanced our knowledge of ways to design more rational drugs. In addition to extensive thermodynamic studies, ongoing works are needed to enhance the exploration of drug-protein binding kinetics. In this work, the beta2-adrenoceptor ( β 2 -AR) was immobilized on N , N ’-carbonyldiimidazole activated amino polystyrene microspheres to prepare an affinity column (4.6 mm × 5.0 cm, 8 μm). The β 2 -AR column was utilized to determine the binding kinetics of five drugs to the receptor. Introducing peak profiling method into this receptor chromatographic analysis, we determined the dissociation rate constants ( k d ) of salbutamol, terbutaline, methoxyphenamine, isoprenaline hydrochloride and ephedrine hydrochloride to β 2 -AR to be 15 (±1), 22 (±1), 3.3 (±0.2), 2.3 (±0.2) and 2.1 (±0.1) s −1 , respectively. The employment of nonlinear chromatography (NLC) in this case exhibited the same rank order of k d values for the five drugs bound to β 2 -AR. We confirmed that both the peak profiling method and NLC were capable of routine measurement of receptor-drug binding kinetics. Compared with the peak profiling method, NLC was advantageous in the simultaneous assessment of the kinetic and apparent thermodynamic parameters. It will become a powerful method for high throughput drug-receptor interaction analysis. [ABSTRACT FROM AUTHOR]

The β 2 adrenergic receptor ( β 2 -AR) is a prototypical family A G protein-coupled receptor (GPCR) and an excellent model system for studying the mechanism of GPCR activation. Purified β 2 -AR was immobilized on macroporous silica gel to obtain liquid chromatographic stationary phase. The resulting phase was packed into a stainless steel column (4.6 × 50 mm, 7 μm) and used for on-line chromatographic system. When column oven temperature increased from 20.0 °C to 40.0 °C, uncomplete separate chromatographic peaks of ephedrine and pseudoephedrine as receptor conformational probe were gradually merged into one peak, meanwhile retention time and resolution of the probes were reduced correspondingly, which suggested that temperature could regulate protein conformation. Temperature-induced conformational change of immobilized β 2 -AR, especially changes at higher temperatures, indicated that constructed receptor chromatography could simulate fever disease state of human body and clarify receptor conformation change at pathological condition. At the same time this study could also provide new ideas for screening active components in pathological conditions. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) is an ultrasensitive technique for both detection and structural characterizations. To further exploit these advantages, we designed and fabricated a dual-functional SERS probe for specific capture and fast detection of small molecule ligands binding to target protein from a mixture of compounds such as extracts of natural products. As a proof of concept, we synthesized SiO 2 @Ag nanoclusters that are coated with 6-chlorohexanoic acid for covalent immobilization of serotonin transporter (5-HTT) fused with a Halo-tag through enzyme-substrate recognition. As such, we fabricated a bioconjugated SERS probe, and the synthesis, coating, protein immobilization, and affinity-based ligand binding have been characterized and verified by transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and elemental mapping. By applying this probe to analyze Gardenia jasminoides extract, we have successfully identified crocin I as a compound binding to 5-HTT, which was further proved by using mass spectrometry (MS) and nuclear magnetic resonance (NMR). Taken together, we have developed a novel SERS probe by integrating the inherent strength of SERS in molecular analysis with an extended functionality of affinity-guided molecular capture, which has demonstrated the potential in drug screening of challenging systems. [ABSTRACT FROM AUTHOR]

Owing to the promising clinical efficacy and relatively simple composition, Shuang-Huang-Lian prescription is widely prescribed for the treatment of acute upper respiratory tract infection and acute bronchitis in practice. This necessitates the understanding of the bioactive compounds of the prescription and their binding mechanism to β2-adrenoceptor, which mediates the aforementioned ailments. In this work, a column containing immobilized β2-adrenoceptor was prepared using a diazonium salt reaction. The bioactive compound collected from the β2-adrenoceptor column was identified as chlorogenic acid by using high-performance liquid chromatography coupled with ion trap mass spectrometry. Using an injection amount dependent method, chlorogenic acid proved the binding to β2-adrenoceptor through two kinds of sites. The numbers of the sites were (1.42 ± 0.03) × 10−8 and (9.06 ± 0.49) × 10−8 M. The association constants were (2.72 ± 0.01) × 105 and (2.80 ± 0.01) × 104 M−1, respectively. Molecular docking analysis of the interaction between chlorogenic acid and β2-adrenoceptor indicated that the binding mainly occurred on Ser169, Ser173, and Phe287 of β2-adrenoceptor. These results paved the way to screen bioactive compounds of other traditional medicines by receptor chromatography. [ABSTRACT FROM AUTHOR]

Drug-protein interaction analysis is pregnant in designing new leads during drug discovery. We prepared the stationary phase containing immobilized β2-adrenoceptor ( β2 -AR) by linkage of the receptor on macroporous silica gel surface through N, N′-carbonyldiimidazole method. The stationary phase was applied in identifying antiasthmatic target of protopine guided by the prediction of site-directed molecular docking. Subsequent application of immobilized β2 -AR in exploring the binding of protopine to the receptor was realized by frontal analysis and injection amount-dependent method. The association constants of protopine to β2 -AR by the 2 methods were (1.00 ± 0.06) × 105M−1 and (1.52 ± 0.14) × 104M−1. The numbers of binding sites were (1.23 ± 0.07) × 10−7M and (9.09 ± 0.06) × 10−7M, respectively. These results indicated that β2 -AR is the specific target for therapeutic action of protopine in vivo. The target-drug binding occurred on Ser169 in crystal structure of the receptor. Compared with frontal analysis, injection amount-dependent method is advantageous to drug saving, improvement of sampling efficiency, and performing speed. It has grave potential in high-throughput drug-receptor interaction analysis. [ABSTRACT FROM AUTHOR]

• A protein superglue inspired GPCR immobilization method was established. • Immobilization via Spy toolbox was in situ , site-specific, efficient, and fast. • Magnolol and honokiol were screened from Cortex Magnoliae Officinalis targeting β 2 -AR. The platforms based on immobilization of transmembrane proteins have become an effective way to study drug-protein interaction and identify new leads for drug discovery. Herein, we exploited the protein superglue (i.e. SpyTag-SpyCatcher chemistry) for site-specific, oriented, and in-situ one-step beta2-adrenoceptor (β 2 -AR) immobilization. SpyCatcher was used as a fusion tag at the C-terminal of β 2 -AR and the macroporous silica gels were functionalized with the SpyTag peptide. Immobilization was realized by immersing the gels into the E.coli cell lysate containing β 2 -AR-SpyCatcher. Characterization of the functionalized gels was performed by X-ray photoelectron spectroscopy and fluorescence microscopy. Adsorption energy distribution calculation, injection amount dependent analysis (IADA) and nonlinear chromatographic were used for receptor-ligand interaction analysis. The affinity rank order of four ligands to the receptor was tulobuterol> chlorprenaline> salbutamol> terbutaline, which showed highly consistent with data from the radioligand binding assay and the β 2 -AR column prepared by HaloTag technology. Magnolol and honokiol were screened from Cortex Magnoliae Officinalis and proved to promote the expression of the receptor in human airway smooth muscle cells. Our work unraveled the great potential to generate good bioactivity of the immobilized β 2 -AR through Spy toolbox. This technology can be extended to the immobilization of other functional proteins, providing a better alternative in the field of bioanalysis, biosensing, and separation science. [ABSTRACT FROM AUTHOR]

• A new equation for drug-protein interaction analysis was derivatized. • Co-injection of two drugs was realized for measurement of drug-protein binding. • Two-fold higher throughput than typical chromatographic assays was confirmed. Quantifying drug-protein interactions has a pivotal role in both early phase drug development and clinical processes. Diverse affinity chromatographic methods like nonlinear chromatography can realize such quantification, however, their throughputs are challenged due to the loading of a single ligand during each run. This work derivatized a new equation for simultaneously determining the bindings of two ligands to a protein relying on assumption that the retention factors of the ligands are dependent on their injection amounts. Experimental validation of the derivatization was performed on an immobilized endothelin A receptor (ET A R) column taking ambrisentan, bosentan, and macitentan as injecting solutes. All three ligands presented a decrease in retention times along with increasing moles of injection when they were singly injected into the column. Likewise, negative relationships between the retentions and the injection amounts were observed when co-injection of ambrisentan/bosentan or bosentan/macitentan was performed, thus confirming the assumption of the derivatization. The association constants of ambrisentan, bosentan, and macitentan binding to ET A R were (1.42 ± 0.78)×104, (1.81 ± 0.22)×104, and (1.71 ± 0.41)×104 L/mol when each of them was singly loaded on the column. Such data displayed insignificant changes in four weeks thereby providing a proof of good stability of the column during the period. Co-injections of the two ligand pairs resulted in the association constants of (2.97 ± 0.13)×104 for ambrisentan, (2.51 ± 0.87)×104 for bosentan, and (2.88 ± 0.34)×104 L/mol for macitentan. These results were in good agreement with the calculation when each of the ligands was injected alone into the column and demonstrated little differences from the data by nonlinear chromatography. Owning to the simultaneous analysis of two ligands, the throughput of the proposed method was twofold higher than the typical assays including frontal analysis, zonal elution, and nonlinear chromatography. It is possible to become an alternative for rapid analysis of drug-protein interaction. [ABSTRACT FROM AUTHOR]

The way to immobilize a protein onto a solid surface is the cornerstone for developing many bioanalytical assays which are applied in protein functional assay, protein-ligand interaction analysis and drug screening. Most immobilization approaches are established for soluble or cytosolic proteins, however, when it comes to transmembrane proteins (TMPs) like G protein-coupled receptors (GPCRs), they are challenged, and innovation is needed. In the last decade, site-specific immobilization strategies taking advantages of click chemistry and bioorthogonal conjugation have been developed, which have improved the sensitivity, selectivity, and repeatability of the protein based analytical methods. In this review, we focus on the immobilization of TMPs, because they constitute the largest pharmacological targets in clinics and serve as a paradigm to develop new analytical methods for bioanalysis. In particular, we summarize the progresses of site-specific immobilization made for establishing biosensors, bioassays, and chromatographic methods to pursue drug-protein interaction analysis and library screening. • Up-to-date overview of bioinspired site-specific covalent immobilization for transmembrane proteins (TMPs). • Outline practical guidelines for TMP immobilizations. • Summary of current analytical techniques for drug-TMP interactions with prerequisite of protein immobilization. • Recent advances in TMP-affinity chromatography for protein-ligand interactions and high throughput drug discovery. • Future directions for cutting-edge immobilizations and next-generation analytical methods. [ABSTRACT FROM AUTHOR]