78 research outputs found
Hyperspectral Imaging for Assessing Quality and Safety of Meat
Hyperspectral imaging (HSI) technology is a novel nondestructive method and has found various applications in the agricultural and food industry. In this chapter, the employment of HSI for meat quality assessment and safety control was summarized. The quality attributes include sensory attributes (color and marbling), chemical attributes (moisture, protein, intramuscular fat, and fatty acids), and technological attributes (pH, tenderness, and water holding capacity (WHC)). The safety attributes mainly include bacterial contamination and freshness determination. The spectral method is described in terms of the basic working principle, fundamental configurations, analysis period, and applications in meat assessment. In addition, the advantages, disadvantages, and problems to be tackled facing the HSI are also discussed. The current studies have demonstrated that HSI technology can be a potential tool to replace the traditional method for online and simultaneous evaluation of multiple quality and safety attributes of meat
Nanoparticles for multi-modality cancer diagnosis: simple protocol for self-assembly of gold nanoclusters mediated by gadolinium ions
It is essential to develop a simple synthetic strategy to improve the quality of multifunctional contrast agents for cancer diagnosis. Herein, we report a time-saving method for gadolinium (Gd3+) ions-mediated self-assembly of gold nanoclusters (GNCs) into monodisperse spherical nanoparticles (GNCNs) under mild conditions. The monodisperse, regular and colloidal stable GNCNs were formed via selectively inducing electrostatic interactions between negatively-charged carboxylic groups of gold nanoclusters and trivalent cations of gadolinium in aqueous solution. In this way, the Gd3+ ions were chelated into GNCNs without the use of molecular gadolinium chelates. With the co-existence of GNCs and Gd3+ ions, the formed GNCNs exhibit significant luminescence intensity enhancement for near-infrared fluorescence (NIRF) imaging, high X-ray attenuation for computed tomography (CT) imaging and reasonable r1 relaxivity for magnetic resonance (MR) imaging. The excellent biocompatibility of the GNCNs was proved both in vitro and in vivo. Meanwhile, the GNCNs also possess unique NIRF/CT/MR imaging ability in A549 tumor-bearing mice. In a nutshell, the simple and safe GNCNs hold great potential for tumor multi-modality clinical diagnosis
Total flavonoids extracted from Penthorum chinense Pursh mitigates CCl4-induced hepatic fibrosis in rats via inactivation of TLR4-MyD88-mediated NF-κB pathways and regulation of liver metabolism
Background:Penthorum chinense Pursh (PCP) is widely utilized in China to treat a variety of liver diseases. It has been shown that flavonoids inhibit inflammation and have the potential to attenuate tissue damage and fibrosis. However, the mechanisms underlying how total flavonoids isolated from PCP (TFPCP) exert their anti-fibrotic effects remain unclear.Methods: The chemical composition of TFPCP was determined using UHPLC–Q-Orbitrap HRMS. Subsequently, rats were randomly assigned to a control group (Control), a carbon tetrachloride (CCl4)-induced hepatic fibrosis model group (Model), a positive control group [0.2 mg/(kg∙day)] of Colchicine), and three TFPCP treatment groups [50, 100, and 150 mg/(kg∙day)]. All substances were administered by gavage and treatments lasted for 9 weeks. Simultaneously, rats were intraperitoneally injected with 10%–20% CCl4 for 9 weeks to induce liver fibrosis. At the end of the experiment, the liver ultrasound, liver histomorphological, biochemical indicators, and inflammatory cytokine levels were tested respectively. The underlying mechanisms were assessed using Western blot, immunohistochemistry, immunofluorescence, RT-qPCR, and metabolomics.Results: Fourteen flavonoids were identified in TFPCP. Compared with control animals, CCl4-treated rats demonstrated obvious liver injury and fibrosis, manifested as increases in gray values, distal diameter of portal vein (DDPV) and a decrease in blood flow velocity (VPV) in the ultrasound analysis; increased biochemical index values (serum levels of ALT, AST, TBIL, and ALP); marked increases in the contents of fibrotic markers (PC III, COL4, LN, HA) and inflammatory factors (serum TNF-α, IL-6, and IL-1β); and significant pathological changes. However, compared with the Model group, the ultrasound parameters were significantly improved and the serum levels of inflammatory cytokines were reduced in the TFPCP group. In contrast, the expression of TGF-β1, TLR4, and MyD88, as well as the p-P65/P65 and p-IκBα/IκBα ratios, were considerably reduced following TFPCP treatment. In addition, we identified 32 metabolites exhibiting differential abundance in the Model group. Interestingly, TFPCP treatment resulted in the restoration of the levels of 20 of these metabolites.Conclusion: Our findings indicated that TFPCP can ameliorate hepatic fibrosis by improving liver function and morphology via the inactivation of the TLR4/MyD88-mediated NF-κB pathway and the regulation of liver metabolism
Rapid discovery and crystallography study of highly potent and selective butylcholinesterase inhibitors based on oxime-containing libraries and conformational restriction strategies
22 p.-9 fig.-8 tab.Butyrylcholinesterase is regarded as a promising drug target in advanced Alzheimer’s disease. In order to identify highly selective and potent BuChE inhibitors, a 53-membered compound library was constructed via the oxime-based tethering approach based on microscale synthesis. Although A2Q17 and A3Q12 exhibited higher BuChE selectivity versus acetylcholinesterase, the inhibitory activities were unsatisfactory and A3Q12 did not inhibit Aβ1-42 peptide self-induced aggregation. With A2Q17 and A3Q12 as leads, a novel series of tacrine derivatives with nitrogen-containing heterocycles were designed based on conformation restriction strategy. The results demonstrated that 39 (IC50 = 3.49 nM) and 43 (IC50 = 7.44 nM) yielded much improved hBuChE inhibitory activity compared to the lead A3Q12 (IC50 = 63 nM). Besides, the selectivity indexes (SI = AChE IC50 / BChE IC50) of 39 (SI = 33) and 43 (SI = 20) were also higher than A3Q12 (SI = 14). The results of the kinetic study showed that 39 and 43 exhibited a mixed-type inhibition against eqBuChE with respective Ki values of 1.715 nM and 0.781 nM. And 39 and 43 could inhibit Aβ1-42 peptide self-induced aggregation into fibril. X-ray crystallography structures of 39 or 43 complexes with BuChE revealed the molecular basis for their high potency. Thus, 39 and 43 are deserve for further study to develop potential drug candidates for the treatment of Alzheimer’s disease.We gratefully acknowledge financial support from the Shandong Provincial Key Research and Development Project (No. 2019JZZY021011), Science Foundation for Outstanding Young Scholars of Shandong Province (ZR2020JQ31), Foreign Cultural and Educational Experts Project (GXL20200015001), Qilu Young Scholars Program of Shandong University, Distinguished Young and Middle-aged Scholar of Shandong University, the Taishan Scholar Program at Shandong Province, and MINECO (Grants SAF2016-76693-R to A.M), F.C., F.N. and X.B. were supported by the French Ministry of Armed Forces (Direction Générale de l'Armement and Service de Santé des Armées, NBC-5-C-4210). Authors would like to thank the ESRF for long-term beamtime access (MX2329 IBS BAG).Peer reviewe
Chitosan Modification and Pharmaceutical/Biomedical Applications
Chitosan has received much attention as a functional biopolymer for diverse applications, especially in pharmaceutics and medicine. Our recent efforts focused on the chemical and biological modification of chitosan in order to increase its solubility in aqueous solutions and absorbability in the in vivo system, thus for a better use of chitosan. This review summarizes chitosan modification and its pharmaceutical/biomedical applications based on our achievements as well as the domestic and overseas developments: (1) enzymatic preparation of low molecular weight chitosans/chitooligosaccharides with their hypocholesterolemic and immuno-modulating effects; (2) the effects of chitin, chitosan and their derivatives on blood hemostasis; and (3) synthesis of a non-toxic ion ligand—D-Glucosaminic acid from Oxidation of D-Glucosamine for cancer and diabetes therapy
Environmental flow assessment in the Lower Yellow River using habitat simulation and hydrological reference system
The accuracy of the habitat simulation method is often questioned due to limited simulated elements and indicator species. This study established an environmental flow assessment method by coupling fish habitat simulation with hydrological reference system. The environmental flow obtained through the habitat simulation method was corrected by the statistical characteristics of natural flow regime. The environmental flow of the Huayuankou section in the Lower Yellow River was assessed. The results show that the environmental flow demand of the Huayuankou section is 7.9 - 15.4 billion m3/y without consideration of sediment transport. An environmental baseflow of 220 - 400 m3/s is required throughout the year. One to two high flow pulses are needed in the rising-water season to trigger spawning, followed by flow events of 350 - 500 m3/s with more than 1 week duration to create the spawning grounds
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