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A facile one-pot synthesis method for polyethyleneimine-functionalized graphene (PEI-G) was created by employing polyethyleneimine (PEI) as both the reductive and functionalized reagent to reduce and wrap exfoliated graphene oxide (EGO) to maintain the single layer status of graphene without aggregation. Based on the fine conductivity of PEI-G and high selectivity of the aptamer specially designed for kanamycin, a novel electrochemical impedance aptasensor for the highly-sensitive and selective detection of kanamycin in serum was fabricated using PEI-G as the electrode substrate to enhance the electrochemical signal and using the aptamer as a biological recognition unit to promote the selectivity. After the specific capture of kanamycin in the sample, the proposed aptasensor exhibited a fine line response for kanamycin within the range of 10 fM to 100 pM with a detection limit of 5.2 fM. Moreover, the proposed aptasensor also displayed a good reproducibility, stability and specificity, which was suitable for the trace kanamycin analyses in a real serum sample. Therefore, this proposed electrochemical impedance aptasensing strategy opens a new insight into potential applications in the clinical diagnostic use of kanamycin.

Avian leukosis virus (ALV) is an enveloped retrovirus with a single-stranded RNA genome, belonging to the genus Alpharetroviruswithin the family Retroviridae. The disease (Avian leukosis, AL) caused by ALV is mainly characterized by tumor development and immunosuppression in chickens, which increases susceptibility to other pathogens and leads to significant economic losses in the Chinese poultry industry. The government and poultry industry have made lots of efforts to eradicate ALV, but the threat of which remains not vanished. This review provides a summary of the updated understanding of ALV in China, which mainly focuses on genetic and molecular biology, epidemiology, and diagnostic methods. Additionally, promising antiviral agents and ALV eradication strategies performed in China are also included.

Intestinal injury is the primary toxicity of radiotherapy for pelvic and abdominal tumors, and it is also one of the common acute complications of radiotherapy. At present, there are no effective drugs to prevent intestinal injury in the clinic. Zingerone is a natural product with radioprotective effects. In this study, a novel compound (thiazolidine hydrochloride, TZC01) was synthesized by structural modification of zingerone. The effects of TZC01 on preventing intestinal injury from radiation were further investigated in this study. C57BL/6N mice were exposed to a lethal dose of abdominal irradiation (ABI) with and without TZC01 treatments. The morphological changes of the intestine and various makers of intestinal crypt cells were investigated. Treatment with TZC01 improved the survival rate of mice exposed to 12 Gy ABI. Moreover, TZC01 protected the intestinal morphology of mice, decreased the apoptotic rate of intestinal crypt cells, maintained cell regeneration and promoted crypt cell proliferation and differentiation. This study suggests that TZC01 has preventive and therapeutic effects on radiation enteritis by promoting the proliferation and differentiation of crypt cells to protect the small intestine from the toxic effects of ionizing radiation. Furthermore, the study of TCZ01 lays a strong foundation for developing novel radioprotectors with multiple properties.

Dynamic biointerfaces with reversible surface bioactivities enable dynamic modulation of cell–material interactions, thus attracting great attention in biomedical science. Herein, we demonstrated a paradigm shift of dynamic biointerfaces from macroscopical substrates to micron-sized particles by reversible engineering of a phenylboronic acid (PBA)-functionalized magnetic microbead with mussel-inspired cancer cell-targeting peptide. Due to reversible catechol–boronate interactions between the peptides and microbeads, the micron-sized dynamic biointerface exhibited sugar-responsive cancer-targeting activity, showing the potential as a microplatform for magnetic and noninvasive isolation of cancer cells through natural biofeedback mechanism (e.g., human glycemic volatility). Our results demonstrated that the dynamic magnetic platform was capable of selective cancer cell capture (∼85%) and sugar-triggered release of them (>93%) in cell culture medium with high efficiency. More importantly, by using this platform, a decent number of target cells (∼23 on average) could be magnetically isolated and identified from artificial CTC blood samples (1 mL) spiked with 100 cancer cells. In view of the biomimetic nature, high capture efficiency, excellent selectivity, and superiority in cell separation and purification processes, the dynamic magnetic microplatform reported here would be a promising and general tool for rare cell detection and separation and cell-based disease diagnosis.

ABSTRACTIntroduction: Acetyl-CoA Carboxylase (ACC) is an essential rate-limiting enzyme in fatty acid metabolism. For many years, ACC inhibitors have gained great attention for developing therapeutics for various human diseases including microbial infections, metabolic syndrome, obesity, diabetes, and cancer.Areas covered: We present a comprehensive review and update of ACC inhibitors. We look at the current advance of ACC inhibitors in clinical studies and the implications in drug discovery. We searched ScienceDirect (https://www.sciencedirect.com/), ACS (https://pubs.acs.org/), Wiley (https://onlinelibrary.wiley.com/), NCBI (https://www.ncbi.nlm.nih.gov/) and World Health Organization (https://www.who.int/). The keywords used were Acetyl-CoA Carboxylase, lipid, inhibitors and metabolic syndrome. All documents were published before June 2019.Expert opinion: The key regulatory role of ACC in fatty acid synthesis and oxidation pathways makes it an attractive target for various metabolic diseases. In particular, the combination of ACC inhibitors with other drugs is a new strategy for the treatment of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. Expanding the clinical indications for ACC inhibitors will be one of the hot directions in the future. It is also worth looking forward to exploring safe and efficient inhibitors that act on the BC domain of ACC.

In order to reveal the intrinsic nature of the reduction or disappearance of biological activity in the processing and preparation of polysaccharides, and realize the effective control of highly active polysaccharides, the correlation between conformation and immunomodulatory activity of lentinan under different subcritical water temperatures was investigated. The results showed that, compared with the lentinan extracted by hot water (HW-L), with the increase of temperature (100–160 °C), the molecular weight of lentinans decreased (5.041 × 105–1.754 × 106 g/mol) and the rigidity of the chain weakened. The chains gradually loosened and a rigid-flexible transition occurred. At 160 °C, the conformation of lentinan completely changed from triple helix to random coil. In-vitrocell experiments showed that, lentinan at 120 °C could more efficiently promote the proliferation and phagocytosis of RAW264.7 cells, and significantly promote the secretion of NO, TNF-α, IL-6 and IL-1β, exhibiting stronger immunomodulatory activity. But the activity of lentinan decreased sharply at 150–160 °C. These results suggest a significant correlation between polysaccharide chain conformation and immunomodulatory activity under different subcritical water temperature conditions. By adjusting the temperature of subcritical water, the chain conformation of polysaccharides can be controlled, resulting in more efficient extraction of highly active polysaccharides.

Organic-inorganic hybrid and carbaryl-imprinted capillary monolith was synthesized viamethacrylic acid(MAA) as functional monomer, γ-methacryloxypropyltrimethoxysilane(γ-MAPS) as crosslinker and carbaryl as template molecule in an acetonitrile/dichloromethane mixture(1:4, volume ratio). With the capillary column obtained from this monolith, three carbamates(carbaryl, fenobucarb and metolcarb) were separated effectively by electrochromatography with the kMIP/kNIPvalues of 7.57, 1.27 and 1.64, respectively. In 20 mmol/L phosphate buffer solution (pH=3.5) with 30% (volume fraction) of acetonitrile, carbaryl was separated directly from the three-carbamate mixture (carbaryl, fenobucarb and metolcarb) with an effective 15 cm-length imprinted column.

A new molecularly imprinted polymer (MIP) electrochemical sensor was prepared by anchoring an imprinted insulating poly(o-phenylenediamine) film on a glassy carbon electrode (GCE) surface for the determination of acephate in aqueous solution. In this protocol, the selection of a functional monomer was performed computationally using the density functional theory method to evaluate the template–monomer interaction energy. The electrochemical properties of the MIP–GCE were characterized by cyclic voltammetry and alternating current impedance. Under optimal experimental conditions, the peak current of the MIP–GCE performed by differential pulse voltammetry was related to the concentration of acephate in the range from 5.0 × 10−7to 1.0 × 10−4mol L−1. The detection limit of 1.3 × 10−7mol L−1and the limit of quantitation of 4.5 × 1.0−7mol L−1were obtained. The prepared MIP–GCE showed high recognition, sensitivity to acephate, and it provides potential for monitoring acephate residues in foods and water samples.

To separate and enrich EGCG from a mixture of tea catechins, the molecular imprinted polymers (MIPs) were synthesized on silica gel by surface molecular imprinting technique and characterized with Fourier transform infrared spectroscopy (FT-IR), elemental analysis and scanning electronic microscopy (SEM). MIPs exhibited favorable recognition, better selectivity for EGCG than the other monomers, and the descending order was EGCG, (+)-catechin (C), (−)-epicatechin (EC), (−)-epigallocatechin (EGC), (−)-catechin gallate (CG) and (−)-gallocatechin gallate (GCG). These results demonstrated that MIPs could realize the separation and enrichment of EGCG in real sample.

The aim of this study was to investigate the physicochemical and functional properties of polysaccharides from Sagittaria sagittifoliaL. (SSP), extracted by the assistance of multi-mode divergent ultrasound (SSU), with different frequencies (20, 28, 40 kHz) and various combinations (20/28, 20/40, 28/40, 20/28/40 kHz). The results showed that, compared with hot water extraction, multi-mode divergent ultrasound assistance extraction (MDU) not only improved the yield of SSP (SSU-28/40 increased by 43.47%) with lower Mwand higher uronic acid content, but also changed its morphology (p < 0.05). In addition, all SSPs extracted by MDU are heteropolysaccharides with triple helix structure, which contain different molar ratios of rhamnose, arabinose, xylose, mannose, glucose and galactose. Moreover, these polysaccharides displayed higher foam capacity, foam stability, thermal stability, significant scavenging on DPPH, ABTS and hydroxyl radicals, and better inhibitory effects on HepG2 and MCF-7 cells in vitro. These results indicated that MDU may contribute to the degradation of polysaccharides, promote the transformation of monosaccharide, and improve the yield, solubility, antioxidant activity, and anti-tumor activity of SSP, suggesting that MDU has great potential application prospects in food, medicine, cosmetics and other fields.

Lipoxidation caused by ultrasound treatment was investigated. Its effects on total phenol content (TPC), total flavonoid content (TFC), antioxidant activity (AA) and phenols extraction kinetics in Tartary buckwheat extracts were also studied. Malondialdehyde (MDA) levels and peroxide value (PV) were used to measure lipoxidation. Kinetic modeling of phenol extraction was also done according to Fick's second law of diffusion. Increasing treatment time increased TPC, TFC and AA significantly (p < 0.05) and increments in MDA and PV were significant after 45 min. Increases in MDA and PV correlated with reductions in TPC, TFC and AA. Phenol diffusion followed a kinetic curve that agrees with the classical solid-liquid extraction models, with a rapid initial phase and a slow phase at the end. The effective diffusion coefficients (De), both De-rapidand De-slow, for phenols positively correlated with time (5–60 min) and temperature (20–80 °C). TPC increased when extraction temperature and time increased with De-rapidfrom 3.30 to 7.97 × 1011m2s-1from 20 to 80 °C and 2.88 to 7.47 × 1011m2s-1from 5 to 60 min. The De-slowphase also increased from 2.02 to 5.21 × 1012m2s-1and 2.85 to 4.33 × 1012m2s-1, respectively, for the same range of extraction temperatures and times. It is recommended that ultrasound assisted extraction of phenols from polyunsaturated fatty acid-rich sources are done at temperatures below 65 °C and not for extended periods to preserve bioactivity and minimize lipoxidation.

Ultrasound assisted extraction (UAE) is widely used in recent times for its benefits, but it is difficult to find literature that comprehensively addresses the effect of UAE-specific parameters such as temperature, frequency, power, solvent type, and solvent to material ratio on extracted compounds and their functionality. There is no review done so far on the effects of all UAE parameters on polyphenol extracts to guide the design of extraction protocols. This review therefore focuses on the effects of UAE parameters on the yield and composition, as well as the effects of the UAE on the antioxidant, anticancer, and antimicrobial properties of phenolic extracts. Higher extraction temperatures above 50 °C are degradative to polyphenols in extracts; lower frequencies within the power ultrasound range below 40 kHz are most effective; polyphenol yield generally increases with increasing power, but with a threshold, beyond which no significant increase is observed; and higher ultrasound power produces free hydroxyl radicals which degrade polyphenols, especially in the presence of high water content. A comparative assessment of literature showed that, UAE does not only contribute to increased extraction yield of polyphenols, but also better preserves and increases the biological activity of polyphenol extracts compared to traditional maceration and Soxhlet extraction. A full picture of UAE is given to serve as a reference material on the control of UAE parameters for desired results and efficiency.