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Most proteins perform their functions in cells. How the cellular environment modulates protein interactions is an important question. In this work, electrostatic interactions between protein charges were studied using in-cell nuclear magnetic resonance (NMR) spectroscopy. A total of eight charge pairs were introduced in protein GB3. Compared to the charge pair electrostatic interactions in a buffer, five charge pairs in cells displayed no apparent changes whereas three pairs had the interactions weakened by more than 70%. Further investigation suggests that the transfer free energy is responsible for the electrostatic interaction modulation. Both the transfer free energy of the folded state and that of the unfolded state can contribute to the cellular environmental effect on protein electrostatics, although the latter is generally larger (more negative) than the former. Our work highlights the importance of direct in-cell studies of protein interactions and thus protein function.

La0.8Ce0.2Mn0.6Ni0.4O3 with (LCMN@CuO) and without (LCMN) CuO addition are prepared by solution methods, followed by reduction in 5% H2–N2 stream at 650 °C to form Ni exsolved and CuO reduced catalysts, LCMN@Ni and LCMN@Ni/Cu, for ethanol (EtOH) steam reforming (ESR). The catalysts are characterized by X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy etc., and are evaluated for ESR with a steam/carbon ratio of 3 and a weight hourly space velocity (WHSV) of 4 h−1 at temperatures between 500 and 700 °C. Ni exsolution and CuO reduction are confirmed on the substrates in LCMN@Ni and LCMN@Ni/Cu. Both the catalysts demonstrate a complete conversion of EtOH, forming mainly H2, CO2, CO and CH4. And increasing temperature to 700 °C increases the yields of H2 and CO to the levels about 90% and 40%, respectively, at the cost of CH4; and such performance remains unchanged for 30 h. These results indicate that both LCMN@Ni and LCMN@Ni/Cu are promising catalysts for ESR, the main difference between them is that the latter is more chemically stable and more resistant to carbon deposition under ESR conditions.

Introduction The Epimedium herb, Yinyanghuo in Chinese, is a famous Chinese herbal medicine. In this study, an efficient extraction method was developed for the extraction of major bioactive constituent epimedin A, epimedin B, epimedin C and icariin from E. pubescens Maxim. using deep eutectic solvents (DESs). Methodology A series of choline chloride-based DESs were synthesised for the extraction of four target compounds. DES composed of lactic acid and choline chloride with the ratio of 2:1 was selected as the most promising. Three vital factors affecting the extraction yields including water content, volume of DES aqueous solution and extraction time were optimised systematically by Box-Behnken experimental design in combination with response surface methodology. A high-performance liquid chromatography ultraviolet (HPLC-UV) method was developed for the sensitive and accurate quantification. Results The optimal extraction conditions were obtained as follows: water content of 17.5% (v/v), volume of DES aqueous solution 3.14 ml, and extraction time of 21 min. Under the optimal extraction conditions, the developed DES method could supply almost the same extraction yield as 50% ethanol, which were 98%, 99%, 97%, 96% for epimedin A, epimedin B, epimedin C and icariin, respectively. Conclusion The present study exhibited high efficiency in extraction of prenylflavonol glycosides in E. pubescens Maxim. Thus, DESs could be used as an alternative for efficient extraction and quantification of biologically active components from natural medical plants.

Background: The efficacy of anti-human epidermal growth factor receptor 2 (HER2/neu) treatment is impacted by tissue-based evaluation bias due to tumor heterogeneity and dynamic changes of HER2 in breast cancer. Circulating tumor cell (CTC)-based HER2 phenotyping provides an integral and real-time assessment, benefiting accurate HER2 diagnosis for improved therapeutics.Methods: The study was exploratory. Fifty-four breast cancer patients, including 26 histopathologic HER2/neu-positive (Histo-HER2/neu+) and 28 HER2/neu-negative (Histo-HER2/neu+), were enrolled for blood draws before a new line of treatment. We used peptide-functionalized magnetic nanoparticles to isolate CTCs from 2.0 mL whole blood and determined HER2 phenotypes of the enriched CTCs by immunocytochemistry (ICC). We investigated the correlation of the enumeration and HER2 phenotyping on baseline CTCs with the diagnosis, the prognosis, and the efficacy of the trastuzumab in combination with chemotherapeutic agents of breast cancer. We also explored the dynamic change of HER2 phenotypes on CTCs after the combination therapy in a cohort of Histo-HER2/neu+ individuals (n = 14).Results: We achieved high-efficient detection of the CTC-positive cases (≥ 3 CTCs) (38/54, 70.4%), from whom 71.1% (27/38) had a concordant HER2 status on CTCs and tumor tissues at baseline. Pretheraputic CTC enumeration showed a significant correlation with the histopathologic diagnosis (e.g. estrogen receptor/progesterone receptor (ER/PR) status or proliferation of cancer cells) and the progression-free survival/overall survival (PFS/OS) of breast cancer. However, it was not a practicable biomarker to predict the efficacy of the trastuzumab-based combination therapy. In contrast, we demonstrated a significantly higher possibility of good overall responses in the patients with < 3 CTCs (P = 0.006) or with HER2 overexpression in CTCs (CTC-HER2+) at baseline, as compared to the individuals without HER2 overexpression in CTCs (CTC-HER2–) (P = 0.028).Conclusions: We demonstrate the significance of the peptide-functionalized magnetic nanoparticle in noninvasive detection and HER2 phenotyping of CTCs, and highlight its diagnostic and prognostic values for the patients about to start the anti-HER2 treatment.

Proanthocyanidins is flavan-3-ol polymers with many activities which attracted a lot of attention. However, most of the proanthocyanidins come from fruits and seeds, resulting in higher costs. The extraction of proanthocyanidins from leaves that were trimmed as wastes from fruit trees is of good economic benefits. The proanthocyanidins in persimmon leaves and loquat leaves were extracted and purified. The purity of persimmon and loquat leaves were 85.33 ± 0.11% and 88.45 ± 0.96% with yield of 3.40% and 2.37% respectively. Detailed structure information was analyzed. Persimmon leaves proanthocyanidins mainly consist of catechin with B-type link along with a small portion of gallocatechin, catechin gallate and A-type link. Loquat leaves proanthocyanidins consist of catechin, gallocatechin, gallocatechin gallate and afzelechin with B-type link along with a small portion of A-type link. The α-amylase inhibition effect of the two leaves was analyzed. Persimmon leaves proanthocyanidins and loquat leaves proanthocyanidins were two mixed-type inhibitors to α-amylase.

Although numerous in vitro studies have shown that osmolytes are capable of stabilizing proteins, their effect on protein folding in vivo has been less understood. In this work, we investigated the effect of osmolytes, including glycerol, sorbitol, betaine, and taurine, on the folding of a protein GB3 variant in E. coli cells using NMR spectroscopy. 400 mM osmolytes were added to E. coli cells; only glycerol stabilizes the folded protein, whereas betaine and taurine considerably destabilize the protein through modulating folding and unfolding rates. Further investigation indicates that betaine and taurine can enhance the quinary interaction between the protein and cellular environment and manifestly weaken the electrostatic attraction in protein salt bridges. The combination of the two factors causes destabilization of the protein in E. coli cells. These factors counteract the preferential exclusion mechanism that is adopted by osmolytes to stabilize proteins.

Objectives Alcohol dependence causes extensive damage to the central nervous system, resulting in impaired brain structure and behavioral changes. Moreover, histone deacetylase (HDAC) inhibitors restrain the activity of HDAC and cause increased histone acetylation, which may be related to alcohol dependence. Methods Ethanol dependence was modelled in animals by persistent alcohol exposure and tested in the conditioned place preference (CPP) paradigm. To induce CPP, the alcohol-treated rats were given orally gradient concentration (3%, 6%, and 9% v/v) alcohol administration for 20 consecutive days. The sodium butyrate (NaB)-treated rats were injected daily. Cognitive flexibility was evaluated using an attentional set-shifting task (ASST) in which the rats performed a series of seven consecutive discriminations after the final CPP paradigm. Results Ethanol administration induced alcohol dependence behaviors, with more time spent in the ethanol-paired compartment. Compared with the CPP scores of the control group, the scores of the ethanol- and NaB-treated groups were significantly higher. In the ASST, alcohol-treated rats had significantly increased number of trials to reach criteria (TTC) in most phases, higher error rate, and lower cognitive levels compared to the control group. Moreover, the present findings demonstrated that NaB combined with ethanol caused cognitive deficits as the result of an increased number of TTC during the ASST. Conclusions The attentional/cognitive flexibility of the prefrontal cortex of alcohol-dependent rats was damaged and the NaB administration procedure itself did not produce cognitive deficits, but instead exacerbated cognitive impairment in alcohol-dependent rats.

α-Glucosidase is a key enzyme related to starch digestion and type-2 diabetes. In the present study, the inhibition effect and the underlying mechanism of Chinese bayberry leaves proanthocyanidins (BLPs) on α-glucosidase were investigated by enzyme kinetic analysis, multi-spectroscopy and molecular docking simulation. The results revealed that BLPs was a high potential noncompetitive-type inhibitor of α-glucosidase with the half maximal inhibitory concertation (IC50) value of 0.037 ± 0.001 mg mL−1 and acarbose equivalent (AE) of 517.01 mmol AE g−1. What’s more, BLPs may interact with some amino acids surrounded in the allosteric site of α-glucosidase to form a complex driven by hydrogen bonding and hydrophobic interaction, and thus change the structure and microenvironment of α-glucosidase, leading to the decrease of activity of α-glucosidase. The present study suggested that BLPs as epigallocatechin-3-O-gallate (EGCG) polymers could be a novel α-glucosidase inhibitor and had potential to be further used in functional food or anti-diabetic drug.

We have determined the interaction strengths of the common naturally occurring amino acids using a complete binding affinity matrix of 20 × 20 pairs of homo-octapeptides consisting of the 20 common amino acids between stationary and mobile states. We used a bead-based fluorescence assay for these measurements. The results provide a basis for analyzing specificity, polymorphisms, and selectivity of inter-amino-acid interactions. Comparative analyses of the binding energies, i.e., the free energies of association (ΔGA), reveal contributions assignable to both main-chain-related and side-chain-related interactions originating from the chemical structures of these 20 common amino acids. Side-chain–side-chain and side-chain–main-chain interactions are found to be pronounced in an identified set of amino acid pairs that determine the basis of inter-amino-acid recognition., Interaction strengths between common amino acids were measured with a bead-based fluorescence assay. The results provide a basis for analyzing specificity and selectivity of inter-amino-acid recognition.

In this study, a covalent organic framework designated as TpPaNO2 was synthesized by a mechanochemical grinding method and then coated on stainless steel wire by a sol-gel technique to prepare a solid-phase microextraction fiber. The TpPaNO2 fiber based solid-phase microextraction coupled with gas chromatography-electron capture detection was applied to determine the residues of 11 pesticides (trlfuralln, dicofol, α-endosulfan, 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene, nitrofen, β-endosulfan, 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethyl]benzene, 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane, bifenthrin, permethrin and fenvalerate) in vegetable and fruit samples. The effects of extraction time, extraction temperature, sample pH, stirring rate and desorption temperature on the extraction efficiency were investigated. Under the optimized conditions, the limits of detection for the eleven pesticides were in the range of 0.04-0.25 μg/kg. The recoveries of the eleven pesticides in the vegetable and fruit samples were 81.5-111% with the relative standard deviations less than 11.2%.

Headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry was adopted for the simultaneous determination of seven chlorophenols (CPs) from honey and canned-yellow-peach samples. A covalent organic framework made of 1,3,5-triformylphloroglucinol (Tp) and benzidine (BD) was used as the SPME fiber coating to preconcentrate the acetylation derivatives of the CPs. The main experimental parameters including derivatization conditions, extraction temperature and time, headspace volume, salt concentration, and desorption temperature were investigated. The fiber showed a high extraction capability for the CPs. The limits of detection (LODs) for the analytes were 0.3-0.7 μg kg

Directly modulating the choice between homologous recombination (HR) and non-homologous end joining (NHEJ) - two independent pathways for repairing DNA double-strand breaks (DSBs) - has the potential to improve the efficiency of gene targeting by CRISPR/Cas9. Here, we have developed a rapid and easy-to-score screening approach for identifying small molecules that affect the choice between the two DSB repair pathways. Using this tool, we identified a small molecule, farrerol, that promotes HR but does not affect NHEJ. Further mechanistic studies indicate that farrerol functions through stimulating the recruitment of RAD51 to DSB sites. Importantly, we demonstrated that farrerol effectively promotes precise targeted integration in human cells, mouse cells and mouse embryos at multiple genomic loci. In addition, treating cells with farrerol did not have any obvious negative effect on genomic stability. Moreover, farrerol significantly improved the knock-in efficiency in blastocysts, and the subsequently generated knock-in mice retained the capacity for germline transmission.

Chinese bayberry leaves proanthocyanidins (BLPs) belongs to the prodelphinidin category with potent EGCG unit, whose inhibition effect on α-amylase and their interaction were investigated by in vitro digestion and enzyme kinetic analysis, multi fluorescence spectroscopies (fluorescence quenching, synchronous fluorescence, and three-dimensional fluorescence), circular dichroism spectra, Fourier transform infrared spectroscopy and in silico modelling. The results revealed that BLPs was a mixed inhibitor to α-amylase with the IC50 value of 3.075 ± 0.073 μg/mL. BLPs could lead to a static fluorescence quenching of α-amylase, mainly by means of interacting with amino acids (mainly Try and Tyr residues) in one site on α-amylase molecule under the action of hydrogen bonding and/or Van der Waals force. This interaction further induced the change of secondary conformational structure, functional group structure and hydrophobicity of α-amylase, thus resulting in lowering activity. Molecular docking simulated that this binding occurred in a cavity on the surface of the α-amylase molecule, and BLPs trimer showed a relatively high binding energy. The present study provided a new insight of BLPs as an α-amylase inhibitor, which could be considered in anti-diabetic therapy.

Chinese bayberry leaf proanthocyanidins (BLPs) are Epigallocatechin gallate (EGCG) oligomers or polymers, which have a lot of health-promoting activity. The activity is closely related to their behavior during in vitro digestion, which remains unknown and hinders further investigations. To clarify the changes of BLPs during gastrointestinal digestion, further research is required. For in vitro digestion, including gastric-intestinal digestion, colon fermentation was applied. Caco-2 monolayer transportation was also applied to investigate the behavior of different BLPs with different degrees of polymerization. The trimers and the tetramers were significantly decreased during in vitro gastric-intestinal digestion resulting in a significant increase in the content of dimers. The dimers and trimers were the main compounds utilized by gut microbiota and they were assumed not to degrade through cleavage of the inflavan bond. The monomers and dimers were able to transport through the Caco-2 monolayer at a rate of 10.45% and 6.4%, respectively.

A solid-phase microextraction with carbon nanospheres coated fiber coupled with gas chromatographic detection was established for the determination of eight polycyclic aromatic hydrocarbons (naphthalene, biphenyl, acenaphthene, fluorine, phenanthrene, anthracene, fluoranthene, and pyrene) in water and soil samples. The experimental parameters (extraction temperature, extraction time, stirring rate, headspace volume, salt content, and desorption temperature) which affect the extraction efficiency were studied. Under the optimized conditions, good linearity between the peak areas and the concentrations of the analytes was achieved in the concentration range of 0.5-300 ng/mL for water samples, and in the concentration range of 6.0-2700 ng/g for soil samples. The detection limits for the analytes were in the range of 0.12-0.45 ng/mL for water samples, and in the range of 1.53-2.70 ng/g for soil samples. The method recoveries of the polycyclic aromatic hydrocarbons for spiked water samples were 80.10-120.1% with relative standard deviations less than 13.9%. The method recoveries of the analytes for spiked soil samples were 80.40-119.6% with relative standard deviations less than 14.4%. The fiber was reused over 100 times without a significant loss of extraction efficiency.

The metal detoxification mechanism is essential for the accumulation activity of some polychaetes. In order to investigate the detoxification function of metalloprotein II in polychaete Perinereis aibuhitensis, a recombinant fusion protein of MP II was successfully expressed in vitro and an anti-MP II polyclonal antibody was got. The tissue distribution of MP II in P. aibuhitensis and the protein expression under Cd, Pb and Zn exposure were detected by ELISA with this antibody. The results showed that MP II was higher in the intestine of P. aibuhitensis, followed by the body wall and parapodium. Cd, Zn and Pb exposure can induced MP II expression, but the change trend of MP II under various heavy metal exposure was different. The amount of MP II induced in P. aibuhitensis increased with the rises of Cd concentration, but there is no significant relationship between Zn and Pb concentration and MP II level.

A functionalized covalent organic framework (COF) was synthesized via room-temperature solvent-free mechano-chemical grinding method and used as a solid-phase extraction adsorbent for the extraction of eight biogenic amines (tryptamine, n-butylamine, phenylethylamine, cadaverine, putrescine, tyramine, spermine, and spermidine) in diverse meat samples. The target biogenic amines were derived with dansyl chloride to form stable fluorogenic derivatives for their high-performance liquid chromatography–fluorescence detection. The main important experimental parameters were investigated and optimized by both one-factor-at-a-time and response surface methodologies. Under the optimum conditions, a linear response for the biogenic amines was observed in the concentration range of 5.0–800.0 μg L−1 with the coefficients of determination (r2) ranging from 0.9944 to 0.9981. The limits of detection of this method (at a signal-to-noise ratio of 3) for the analytes ranged from 0.92 to 2.57 μg L−1. The method recoveries of the target biogenic amines for five meat samples ranged from 80.3 to 115%, with relative standard deviations lower than 12%. The results indicate that the prepared COF is an effective adsorbent for the enrichment of biogenic amines.

Lotus leaf flavonoids (LLF) are a group of bioactive natural substances. In this study, the structure, thermal properties, rheology behaviors and in vitro digestibility of cooked LLF-starch complex were investigated. Differential scanning calorimetry (DSC) analysis showed the shift in gelatinization peak to a higher temperature and the decrease in gelatinization enthalpies in the complexes significantly. The short-term retrogradation was retarded either. The flow behaviors of starch pastes changed with adding LLF. Scanning electron microscope (SEM) images showed a less compact structure in LLF-starch complex and laser confocal scanning microscope (CLSM) images detected that LLF mostly distributed around starch granules, which further prove the binding between LLF and starch. Moreover, fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) elucidated LLF probably interacted with starch by non-covalent bond especially hydrogen bond. In addition, LLF-starch complex exhibited inhibitory effect on starch digestion compared to pregelatinized starch, and the reasonable content of LLF-starch complex was (0.7 g/100 g). Thus, LLF-starch complex can be potentially used as a functional additive for high resistant starch (RS) and low glycemic index (GI) diets.

Multifunctional nanoplatforms for imaging‐guided synergistic antitumor treatment are highly desirable in biomedical applications. However, anticancer treatment is largely affected by the pre‐existing hypoxic tumor microenvironment (TME), which not only causes the resistance of the tumors to photodynamic therapy (PDT), but also promotes tumorigenesis and tumor progression. Here, a continuous O2 self‐enriched nanoplatform is constructed for multimodal imaging‐guided synergistic phototherapy based on octahedral gold nanoshells (GNSs), which are constructed by a more facile and straightforward one‐step method using platinum (Pt) nanozyme‐decorated metal–organic frameworks (MOF) as the inner template. The Pt‐decorated MOF@GNSs (PtMGs) are further functionalized with human serum albumin‐chelated gadolinium (HSA‐Gd, HGd) and loaded with indocyanine green (ICG) (ICG‐PtMGs@HGd) to achieve a synergistic PDT/PTT effect and fluorescence (FL)/multispectral optoacoustic tomography (MSOT)/X‐ray computed tomography (CT)/magnetic resonance (MR) imaging. The Pt‐decorated nanoplatform endows remarkable catalase‐like behavior and facilitates the continuous decomposition of the endogenous H2O2 into O2 to enhance the PDT effect under hypoxic TME. HSA modification enhances the biocompatibility and tumor‐targeting ability of the nanocomposites. This TME‐responsive and O2 self‐supplement nanoparticle holds great potential as a multifunctional theranostic nanoplatform for the multimodal imaging‐guided synergistic phototherapy of solid tumors., In this research, a tumor environment (TEM)‐responsive and continuous O2 self‐enriched drug delivery platform based on octahedral gold nanoshells (GNSs) using Pt‐decorated metal–organic frameworks (MOF) as inner template is constructed. The obtained nanostructures are further functionalized with human serum albumin‐gadolinium hybrid (HSA‐Gd, HGd) and loaded with indocyanine green (ICG) (ICG‐PtMGs@HGd) to achieve a multimodal imaging guided enhanced photodynamic therapy/photothermal therapy PDT/PTT effect.

Due to the misuse of hormones and antibiotics resulting in drug residues in meat products, serious concerns have arisen regarding to the potential risks for human health. In this paper, a simple and efficient method was developed to simultaneously quantify six steroid hormones and six antibiotics in fatty foods by combining pressurized liquid extraction (PLE) with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Adsorbents, extraction temperature, extraction time, recycle time and several other parameters were optimized in current investigation. The optimized PLE method was employed by using n-hexane-methanol-acetonitrile (2:1:1, v/v/v) as extraction solvent, silica gel as lipid sorbent, and the optimum parameters were 60 °C, 1500 psi and 10 min, respectively. Under the optimal conditions, the recoveries of spiked samples ranged from 82.2% to 115.0%. The limits of quantifications (LODs) were from 0.4 to 25.0 μg/kg. The developed PLE method was successfully applied to analyze steroid hormones and antibiotics in 27 fatty foods of hotpot ingredients without any additional clean-up steps. The results showed that the residues of estradiol benzoate (EB) and enrofloxacin (EN) in some matrices were much higher than maximum residue limits (MRLs) value, especially EB in fish, which exceeded 176.7 μg/kg. The results demonstrated that the developed method was sensitive and efficient in testing hotpot ingredients, and was an excellent analytical tool for monitoring residues of steroid hormones and antibiotics in fatty foods.

A fibrous magnetic boron nitride nanocomposite was synthesized and is shown to be a viable adsorbent for the magnetic solid phase extraction of pesticides prior to their quantitation by gas chromatography with electron capture detection. The optimum conditions were obtained by both single factor optimization and response surface analysis (Box-Behnken design). Under the optimized conditions, the response to the ten pesticides (dicofol, α-endosulfan, p,p’-DDE, nitrofen, β-endosulfan, p,p’-DDD, p,p’-DDT, bifenthrin, permethrin and fenvalerate) is linear in the 0.03–40 ng·mL−1 concentration range with the coefficients of determination ranging from 0.9970 to 0.9992. The relative standard deviations at concentration levels of 0.5 ng·mL−1, 20 ng·mL−1 and 40 ng·mL−1 were below 8.7%. The recoveries of the analytes from spiked tea water and tea beverage samples varied between 84.5% and 122%, with relative standard deviations ranging from 4.8 to 12%. The limits of detection are between 0.01 and 0.05 ng·mL−1. The adsorbent can be reused over 50 times without significant loss of extraction efficiency.

The inhibition effect of three common proanthocyanidins (PA) on the retrogradation properties of maize starch was investigated (including grape seed proanthocyanidins (GSPA), peanut skin proanthocyanidins (PSPA), and pine bark proanthocyanidins (PBPA)). Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis showed that PA could significantly decrease the values of melting enthalpy of retrogradation (ΔHr) and the degree of relative crystallinity, suggesting that the starch re-crystallization was retarded by PA. Scanning electron microscope (SEM) characterizations illustrated that retrograded PA-starch samples formed a looser matrix with less appearance of continuous flakes during storage. Overall, 0.5 %-2.0 % of three PAs exhibited suppression of starch retrogradation after 21-day cooling storage, mainly resulting from the PA-starch interaction. Among them, PSPA showed the most substantial inhibition effect on starch retrogradation, which might be attributed to its structural features. This study suggested that PA could be a new type of inhibitor to suppress starch retrogradation.

Small molecular gels (SMGs) have drawn much attention due to their unique properties which can be used in wide range of applications. In this work, the two-component hydrogels based on intermolecular interaction were prepared by the mixing appropriate ratios of melamine (M) and nitrilotriacetic acid (N) in pure water. These obtained hydrogels, which own a three-dimensional (3D) supramolecular structure, responded to several external stimuli such as temperature, pH and halogen ions. Otherwise, the two-component hydrogels mixed with M and N in organic-water mixtures were studied by calculating the Hansen Solubility Parameters of the solvents, a gelation range of the known two-component could be defined. The untested solvent lied in this known range might be gelled by M and N, which is a useful model to identify the gelation and the particular application of a suitable two-component hydrogels.

A novel multi-residue method was developed for the simultaneous analysis of tetracyclines and β-receptor agonists in chicken by coupling pressurized liquid extraction (PLE) with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The parameters of PLE method was optimised, such as extraction solvents, extraction temperature and several other parameters. The performance of the method was assessed and compared to QuEChERS extraction and ultrasound assisted extraction, which were widely used for the chicken extraction. PLE method proved to be suitable for the determination of tetracycline and β-receptor agonists, showing high recoveries, in the range of 84.1–107.9% with relative standard deviation less than 20%. PLE provided low LODs for CHL, OX and TE which were 18.0, 42.0 and 54.0 ng/kg respectively. Additionally, matrix effect of the PLE method exhibited slight effect on all target drugs. However, both ultrasound assisted extraction and QuEChERS extraction exhibited low recoveries and high LODs. The results showed that the established PLE method could be applied to the multiresidue analysis of tetracyclines and β-receptor agonists in chicken to ensure the safety of our daily food supply.

Background G-protein-coupled receptors (GPCRs) are one of the most important molecules that transfer signals across the plasma membrane, and play central roles in physiological systems. The molecular architecture of GPCRs allows them to bind to diverse chemicals, including environmental contaminants. Methods To investigate the effects of benzo(a)pyrene (B(a)P) on GPCR signaling, GPCR and the protein kinase A (PKA) catalytic subunit of Perinereis aibuhitensis were cloned. The expression patterns of these two genes during B(a)P exposure were determined with real-time fluorescence quantitative PCR. The PKA content in P. aibuhitensis under B(a)P exposure was examined. Results The full-length cDNAs of PaGPCR and the PaPKA catalytic subunit were 1,514 and 2,662 nucleotides, respectively, encoding 338 and 350 amino acids, respectively. Multiple sequence alignments indicated that the deduced amino acid sequence of PaGPCR shared a low level of similarity with the orphan GPCRs of polychaetes and echinoderms, whereas PaPKA shared a high level of identify with the PKA catalytic subunits of other invertebrates. B(a)P exposure time-dependently elevated the expression of PaGPCR and PaPKA. The expression of both PaGPCR and PaPKA was also dose-dependent, except at a dose of 10 μg/L B(a)P. The PKA content in concentration group was elevated on day 4, with time prolonging the PKA content was down-regulated to control level. Discussion These results suggested that GPCR signaling in P. aibuhitensis was involved in the polychaete’s response to environmental contaminants.

In this study, lotus leaf flavonoids (LLF) were found to show a notable inhibition activity on α-amylase in a mixed-type manner with IC50 value of (5.58 ± 0.10) mg/mL. The intrinsic fluorescence of α-amylase was quenched by the interaction with LLF through a static quenching mechanism, and LLF-α-amylase complex was spontaneously formed mainly driven by the hydrophobic interaction and hydrogen bonding. Multispectroscopic analyses (synchronous fluorescence, three-dimensional fluorescence, circular dichroism (CD) and fourier transform infrared spectra (FT-IR)) comprehensively demonstrated that the binding of LLF to α-amylase would change the conformation and microenvironment of α-amylase, resulting in inhibiting the enzyme activity. The present study indicated that LLF had potential to be as an ingredient in functional food for the prevention of type-2 diabetes.

Steamed pork with pickled and dried mustard (PDM) is a famous Chinese dish. Here, we examined the effects of PDM on nutritional quality, sensory quality, and shelf life of steamed pork belly. Proximate composition, lipid oxidation, fatty acid profiles, protein hydrolysis and oxidation, sensory evaluation, and induction period (IP) of steamed pork belly were determined after addition of different levels (0–100%, WPDM/W pork belly) of PDM. The results demonstrated that PDM could significantly (p

The aim of this paper is to summarise the blocking effects of parthenolide on the cytokines and pathways that cause inflammation. Analyses of the chemical structure of parthenolide have tried to identify the active domains that play key roles in its anti-inflammatory activity. This review focuses on the anti-inflammatory actions of parthenolide in both in vitro and in vivo. These data will be helpful for future investigations into the effects of parthenolide on inflammation.