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1.
Anal Methods ; 16(6): 830-836, 2024 02 08.
Article in English | MEDLINE | ID: mdl-38230660

ABSTRACT

Pyrroloquinoline quinone (PQQ) is a bioactive compound that has attracted significant attention due to its potential health benefits. In this study, we developed a new magnetic molecularly imprinted nanoparticle (MMIN) for the selective extraction and determination of PQQ from food samples. The MMIN was synthesized using a surface molecular imprinting technique with PQQ as the template molecule, Fe3O4 nanoparticles as the magnetic core, and methacrylic acid as the functional monomer. The MMIN exhibited high selectivity and affinity towards PQQ, allowing for efficient extraction and preconcentration of PQQ from complex food matrices. The extracted PQQ was then quantified using HPLC-DAD. The developed method showed good linearity (R2 = 0.9985) and low limits of detection (0.03 µg L-1). The accuracy and precision of the method were evaluated by analyzing spiked food samples, with average recoveries close to 89.8%. The MMIN also demonstrated good reusability, with negligible decrease in extraction efficiency after five cycles of use. Overall, the developed MMIN-based method provides a reliable and efficient approach for the analysis of PQQ in food samples.


Subject(s)
Molecular Imprinting , PQQ Cofactor , Molecular Imprinting/methods , Food , Chromatography, High Pressure Liquid/methods , Magnetics
2.
Food Chem ; 438: 137959, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-37979256

ABSTRACT

In this study, we discovered a novel peptide, Gymepeptide A, with α-amylase inhibitory activity in the water extract of Gynura medica. The structure of Gymepeptide A was determined as CGDREETR using HR-MS, 1H NMR, 13C NMR, and 2D-NMR techniques. Notably, Gymepeptide A possesses a rare double arginine residue structure and exhibits strong α-amylase inhibitory activity. Enzyme dynamic assays, molecular docking experiments, and isothermal titration calorimetry indicated that the double arginine residue structure of Gymepeptide A interacts with amino acid residues in the nearby active site region of α-amylase through hydrogen bonds and van der Waals forces. This interaction effectively inhibits the hydrolysis activity of α-amylase. Furthermore, in vitro starch digestion tests revealed that Gymepeptide A significantly reduced the digestion rate of starch and the concentration of glucose produced after starch digestion. These findings highlight the great potential of Gymepeptide A in decreasing postprandial blood glucose levels.


Subject(s)
Glucose , alpha-Amylases , Molecular Docking Simulation , Starch/chemistry , Arginine
3.
Article in English | MEDLINE | ID: mdl-37656639

ABSTRACT

The existing solutions for nonconvex optimization problems show satisfactory performance in noise-free scenarios. However, they are prone to yield inaccurate results in the presence of noise in real-world problems, which may lead to failures in optimizing nonconvex problems. To this end, in this article, we propose a coevolutionary neural solution (CNS) by combining a simplified neurodynamics (SND) model with the particle swarm optimization (PSO) algorithm. Specifically, the proposed SND model does not leverage the time-derivative information, exhibiting greater stability compared to existing models. Furthermore, due to the noise tolerance capacity and rapid convergence property exhibited by the SND model, the CNS can rapidly achieve the optimal solution even in the presence of various perturbations. Theoretical analyses ensure that the proposed CNS is globally convergent with robustness and probability. In addition, the effectiveness of the CNS is compared with those of the existing solutions by a class of illustrative examples. We further apply the proposed solution to design a finite impulse response (FIR) filter and a pressure vessel to demonstrate its performance.

4.
FASEB J ; 35(7): e21711, 2021 07.
Article in English | MEDLINE | ID: mdl-34107098

ABSTRACT

Podocyte injury is a major determinant of focal segmental glomerular sclerosis (FSGS) and the identification of potential therapeutic targets for preventing podocyte injury has clinical importance for the treatment of FSGS. CLEC14A is a single-pass transmembrane glycoprotein belonging to the vascular expressed C-type lectin family. CLEC14A is found to be expressed in vascular endothelial cells during embryogenesis and is also implicated in tumor angiogenesis. However, the current understanding of the biological functions of CLEC14A in podocyte is very limited. In this study, we found that CLEC14A was expressed in podocyte and protected against podocyte injury in mice with Adriamycin (ADR)-induced FSGS. First, we observed that CLEC14A was downregulated in mice with ADR nephropathy and renal biopsies from individuals with FSGS and other forms of podocytopathies. Moreover, CLEC14A deficiency exacerbated podocyte injury and proteinuria in mice with ADR nephropathy accompanied by enhanced inflammatory cell infiltration and inflammatory responses. In vitro, overexpression of CLEC14A in podocyte had pleiotropic protective actions, including anti-inflammatory and anti-apoptosis effects. Mechanistically, CLEC14A inhibited high-mobility group box 1 protein (HMGB1) release, at least in part by directly binding HMGB1, and suppressed HMGB1-mediated signaling, including NF-κB signaling and early growth response protein 1 (EGR1) signaling. Taken together, our findings provide new insights into the pivotal role of CLEC14A in maintaining podocyte function, indicating that CLEC14A may be an innovative therapeutic target in FSGS.


Subject(s)
Doxorubicin/pharmacology , Kidney Diseases/chemically induced , Kidney Diseases/metabolism , Lectins, C-Type/metabolism , Membrane Proteins/metabolism , Podocytes/metabolism , Animals , Cells, Cultured , Disease Models, Animal , Down-Regulation/physiology , Early Growth Response Protein 1/metabolism , Endothelial Cells/metabolism , Glomerulosclerosis, Focal Segmental/metabolism , Humans , Inflammation/metabolism , Male , Mice , Mice, Inbred C57BL , Proteinuria/metabolism , Signal Transduction/physiology
5.
Hypertension ; 69(2): 259-266, 2017 02.
Article in English | MEDLINE | ID: mdl-27872232

ABSTRACT

Hyperhomocysteinemia (hHcys) is an important independent risk factor for the development of cardiovascular disease and end-stage renal disease. Although multiple approaches lowering the levels of homocysteine have been used in experimental studies and clinical trials, there is no effective therapy available to fully prevent homocysteine-induced injury. Therefore, identifying key molecules in the pathogenic pathways may provide clues to develop new therapeutic strategies for the treatment of hHcys-associated injury beyond lowering the plasma homocysteine levels. In this study, we found that the levels of progranulin (PGRN), an autocrine growth factor, were significantly reduced in the kidney and heart from a mouse model of hHcys. We further observed that in hHcys, PGRN-deficient mice significantly exacerbated cardiorenal injury as evidenced by higher levels of urinary albumin excretion, more severe renal morphological injuries, including pronounced glomerular basement membrane thickening and podocyte foot process effacement, and adverse myocardial remodeling versus wild-type mice. Mechanistically, we found that PGRN-medicated Wnt/ß-catenin signaling was one of the critical signal transduction pathways that links homocysteine to cardiorenal injury. Importantly, we finally provided direct evidence for the therapeutic potential of PGRN in mice with hHcys by pretreatment with recombinant human PGRN. Collectively, our results suggest that PGRN may be an innovative therapeutic strategy for treating patients with hHcys.


Subject(s)
Cardio-Renal Syndrome/prevention & control , Hyperhomocysteinemia/complications , Intercellular Signaling Peptides and Proteins/therapeutic use , Animals , Cardio-Renal Syndrome/diagnosis , Cardio-Renal Syndrome/etiology , Disease Models, Animal , Echocardiography , Granulins , Homocysteine/blood , Hyperhomocysteinemia/blood , Hyperhomocysteinemia/drug therapy , Kidney Glomerulus/drug effects , Kidney Glomerulus/metabolism , Kidney Glomerulus/pathology , Male , Mice , Mice, Inbred C57BL , Microscopy, Confocal , Progranulins , Recombinant Proteins/therapeutic use
6.
J Opt Soc Am A Opt Image Sci Vis ; 32(7): 1366-70, 2015 Jul 01.
Article in English | MEDLINE | ID: mdl-26367167

ABSTRACT

We present a new simultaneous dual-surface design method for uniform illumination by introducing a virtual light source. This method is a combination of the equal optical path length condition and the tailored method. It can be applied to an extended light source after some optimization processes with a negative feedback algorithm. A solid lens to yield a circular uniform irradiance distribution is designed by using our method. Both optical simulation and experiment have been carried out to show that the experimental irradiance map is close to both the simulation result and the desired distribution, and the uniformity is higher than 0.9 while the light source is a 5050 LED chip with SMD package. The rays from the outside lens surface are of good topological invariance, which can give the potential to design more than two smooth freeform optical surfaces simultaneously by introducing multiple virtual point sources.

7.
Appl Opt ; 54(14): 4503-8, 2015 May 10.
Article in English | MEDLINE | ID: mdl-25967508

ABSTRACT

We propose a hybrid method of free-form illumination design for an arbitrary target form, imposing no restriction on the boundary of the irradiance distribution. Smooth continuous surfaces and continuous irradiance distributions are achieved with two independent steps. Initial solutions of the illumination problem are obtained with the method of supporting paraboloids, and final solutions are acquired by numerically solving the elliptic Monge-Ampére equations. Lenses, which are able to produce complex irradiance distributions, can be achieved with this method and fabricated in practice. The feasibility of this approach is demonstrated by some examples with experimental results.

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