Advanced visual sensing techniques for on-site detection of pesticide residue in water environments.

Pesticide usage has increased to fulfil agricultural demand. Pesticides such as organophosphorus pesticides (OPPs) are ubiquitous in world food production. Their widespread usage has unavoidable detrimental consequences for humans, wildlife, water, and soil environments. Hence, the development of more convenient and efficient pesticide residue (PR) detection methods is of paramount importance. Visual detecting approaches have acquired a lot of interest among different sensing systems due to inherent advantages in terms of simplicity, speed, sensitivity, and eco-friendliness. Furthermore, various detections have been proven to enable real-life PR surveillance in environment water. Fluorometric (FL), colourimetric (CL), and enzyme-inhibition (EI) techniques have emerged as viable options. These sensing technologies do not need complex operating processes or specialist equipment, and the simple colour change allows for visual monitoring of the sensing result. Visual sensing techniques for on-site detection of PR in water environments are discussed in this paper. This paper further reviews prior research on the integration of CL, FL, and EI-based techniques with nanoparticles (NPs), quantum dots (QDs), and metal-organic frameworks (MOFs). Smartphone detection technologies for PRs are also reviewed. Finally, conventional methods and nanoparticle (NPs) based strategies for the detection of PRs are compared.

Effects of caffeine, tea polyphenol and daidzein on the pharmacokinetics of lansoprazole and its metabolites in rats

abstract The aim of this study was to evaluate the effects of caffeine, tea polyphenol and daidzein on the pharmacokinetics of lansoprazole and its metabolites. Rats were intragastrically administered caffeine (30 mg·kg-1, once per day), tea polyphenol (400 mg·kg-1, once per day) or daidzein (13.5 mg·kg-1, once per day) for 14 days, followed by an intragastric administration of lansoprazole (8 mg·kg-1) on the 15th day. The plasma concentrations of lansoprazole and its two primary metabolites, 5-hydroxylansoprazole and lansoprazole sulfone, were determined by high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). Tea polyphenol significantly elevated the Area Under the Curve (AUC) of lansoprazole from 680.29 ± 285.99 to 949.76 ± 155.18 μg/L.h and reduced that of lansoprazole sulfone from 268.82 ± 82.37 to 177.72 ± 29.73 μg/L.h. Daidzein increased the AUC of lansoprazole from 680.29 ± 285.99 to 1130.44 ± 97.6 μg/L.h and decreased that of lansoprazole sulfone from 268.82 ± 82.37 to 116.23 ± 40.14 μg/L.h. The pharmacokinetics of 5-hydroxylansoprazole remained intact in the presence of tea polyphenol or daidzein. Caffeine did not affect the pharmacokinetics of lansoprazole and its metabolites. The results imply that tea polyphenol and daidzein may inhibit the in vivo metabolism of lansoprazole by suppressing CYP3A.

resumo O objetivo deste estudo foi avaliar os efeitos da cafeína, do polifenol do chá e da daidzeína na farmacocinética do lansoprazol e de seus metabólitos. Administraram-se, intragastricamente, aos ratos cafeína (30 mg·kg-1, uma vez ao dia), polifenol do chá(400 mg·kg-1, uma vez ao dia) ou daidzeína (13,5 mg·kg-1, uma vez ao dia), por 14 dias, seguindo-se a administração de lansoprazol (8 mg·kg-1) no 15º. dia. As concentrações plasmáticas do lansoprazol e de seus dois metabólitos primários, 5-hidroxilansoprazol e sulfona de lansoprazol, foram determinadas por cromatografia líquida de alta eficiência acoplada com espectrometria de massas (CLAE-EM/EM). O polifenol do chá elevou, significativamente, a Área Sob a Curva (ASC) do lansoprazol de 680,29 ± 285,99 para 949,76 ± 155,18 μg/L.h e reduziu a da sulfona de lansoprazol de 268,82 ± 82,37 para 177,72 ± 29,73 μg/L.h. A daidzeína aumentou a ASC do lansoprazol de 680,29 ± 285,99 para 1130,44 ± 97,6 μg/L.h e reduziu a da sulfona de lansoprazol de 268,82 ± 82,37 para 177,72 ± 29,73 μg/L.h. A farmacocinética do 5-hidroxilansoprazol permaneceu intacta na presença de polifenol do chá ou daidzeína. A cafeína não afetou a farmacocinética do lansoprazol e de seus metabólitos. Os resultados sugerem que o polifenol do chá e a daidzeína podem inibir o metabolismo in vivo do lansoprazol por supressão da CYP3A.

End-organ protection in hypertension by the novel and selective Rho-kinase inhibitor, SAR407899.

AIM: To compare the therapeutic efficacy of SAR407899 with the current standard treatment for hypertension [an angiotensin converting enzyme (ACE)-inhibitor and a calcium channel blocker] and compare the frequency and severity of the hypertension-related end-organ damage. METHODS: Long-term pharmacological characte-rization of SAR407899 has been performed in two animal models of hypertension, of which one is sensitive to ACE-inhibition (LNAME) and the other is insensitive [deoxycorticosterone acetate (DOCA)]. SAR407899 efficiently lowered high blood pressure and significantly reduced late-stage end organ damage as indicated by improved heart, kidney and endothelial function and reduced heart and kidney fibrosis in both models of chronic hypertension. RESULTS: Long term treatment with SAR407899 has been well tolerated and dose-dependently reduced elevated blood pressure in both models with no signs of tachyphylaxia. Blood pressure lowering effects and protective effects on hypertension related end organ damage of SAR407899 were superior to ramipril and amlodipine in the DOCA rat. Typical end-organ damage was significantly reduced in the SAR407899-treated animals. Chronic administration of SAR407899 significantly reduced albuminuria in both models. The beneficial effect of SAR407899 was associated with a reduction in leukocyte/macrophage tissue infiltration. The overall protective effect of SAR407899 was superior or comparable to that of ACE-inhibition or calcium channel blockade. Chronic application of SAR407899 protects against hypertension and hypertension-induced end organ damage, regardless of the pathophysiological mechanism of hypertension. CONCLUSION: Rho-kinases-inhibition by the SAR407899 represents a new therapeutic option for the treatment of hypertension and its complications.

Rapid Screening of Carbamates Pesticide Residues in Vegetables by Electrospray Ionization Mass Spectrometry Based on Principle of Enzyme Inhibition / 分析化学

Arapidscreeningmethodforthedeterminationofcarbamatepesticides(CBPs)residuesin vegetables by measuring acetylcholinesterase ( AChE ) inhibition rate using electrospray ionization mass spectrometry ( ESI-MS ) has been established. After pretreatment by QuEChERS method, sample solution reacts with AChE using acetylthiocholine as substrate. AChE inhibition rate was calculated by determination of the conversion of substrate to product ( thiocholine) using ESI-MS. The temperature, time and concentration conditions of enzymatic reactions have been optimized. The relationship between the concentration of 10 kinds of common CBPs and AChE inhibition rate was researched. Matrix effects of real vegetables were studied. The limit of detection ( LOD) , which was measured by 3 times of enzyme inhibition rate of pesticide-free vegetable samples, was 0. 01-0. 05 mg/kg. The results showed that the method was better than the current national standard method of china for rapid screening of pesticide residues and fully meet the requirements of maximum residue limits( MRL) for pesticides in food of national food safety standard. False positive results were avoided effectively due to its good ability of resistance matrix interference. The reliability was proved by analyzing vegetables with liquid chromatography-tandem mass spectrometry. The method is simple, rapid, sensitive, reliable, and can be used for the rapid, high-throughput screening of CBPs in vegetables.

Inhibition of Ecto-Apyrase and Ecto-ATPase by Pyridoxal Phosphate-Related Compounds.

Studies of nucleotide receptors (P2-receptors) in cells and tissues are complicated by cleavage of phosphate groups from nucleotide agonist ligands by ecto-nucleotidases. Some P2 receptor antagonists may also inhibit ecto-nucleotidases, making these studies even more complex. In order to systematically approach this problem, we investigated structure-activity relationships of pyridoxal-5'-phosphate-6-azophenyl-2,4-disulfonate (PPADS) and 14 derivatives, many potent as antagonists at P2 receptors, as inhibitors of ecto-nucleotidases. The compounds were tested for their ability to inhibit enzymatic nucleotide breakdown by CHO cells stably transfected with plasmids containing the cDNA for rat ecto-apyrase (NTPDase1) and rat ecto-ATPase (NTPDase2). All inhibitors were tested at a concentration of 100 µM and ATP hydrolysis was quantified by HPLC. Maximal inhibition obtained for ecto-apyrase and ecto-ATPase was 60% and 35%, respectively. Most PPADS analogs were better inhibitors of ecto-apyrase than of ecto-ATPase. Compound 8, a phosphate derivative, inhibited ecto-apyrase with no inhibition evident at ecto-ATPase. Comparison of pharmacological data of PPADS analogs at P2 receptors as previously determined showed that four PPADS analogs exhibited selectivity for P2X nucleotide receptors. None of these compounds inhibited ecto-ATPase, while two inhibited the ecto-apyrase. Compound 14, a bisphosphate derivative, inhibited ecto-ATPase without inhibition of ecto-apyrase. This compound only weakly antagonized P2X1 receptors and was inactive at P2X2 and P2Y1 receptors, thus bearing some selectivity for ecto-ATPase. Compound 7, a 5-methylphosphonate derivative, a potent antagonist of P2X1 receptors, was inactive at ecto-apyrase and only weakly inhibitory at ecto-ATPase. Thus, PPADS modifications that enhance selectivity among ecto-nucleotidases and P2 receptors have been identified.