Cai J

References (40)

Title : Discovery of Enzyme Inhibitors from Mangrove Sediment Derived Fungus Trichoderma harzianum SCSIO 41051 - Huang_2024_Chem.Biodivers__e202400070
Author(s) : Huang L , Chen C , Cai J , Chen Y , Zhu Y , Yang B , Zhou X , Liu Y , Tao H
Ref : Chem Biodivers , :e202400070 , 2024
Abstract : One new fatty acid derivative, (2E,4E)-6,7-dihydroxy-2-methylocta-2,4-dienoic acid (1), and 16 known compounds (2-17) were isolated from the mangrove sediment derived fungus Trichoderma harzianum SCSIO 41051. Their structures were established by spectroscopic methods, computational ECD, and Mo2(OAc)4-induced ECD experiment. All the compounds were evaluated for their acetylcholinesterase (AChE) and pancreatic lipase (PL) inhibition. Compounds 9 and 14 exhibited moderate AChE inhibitory activities with IC50 values of 2.49 and 2.92 microM, respectively, which compounds 8 and 9 displayed moderate inhibition on PL with IC50 value of 2.30 and 2.34 microM, respectively.
ESTHER : Huang_2024_Chem.Biodivers__e202400070
PubMedSearch : Huang_2024_Chem.Biodivers__e202400070
PubMedID: 38356321

Title : Bioactive Polyketides and Benzene Derivatives from Two Mangrove Sediment-Derived Fungi in the Beibu Gulf - Peng_2023_Mar.Drugs_21_
Author(s) : Peng B , Cai J , Xiao Z , Liu M , Li X , Yang B , Fang W , Huang YY , Chen C , Zhou X , Tao H
Ref : Mar Drugs , 21 : , 2023
Abstract : To discover bioactive natural products from mangrove sediment-derived microbes, a chemical investigation of the two Beibu Gulf-derived fungi strains, Talaromyces sp. SCSIO 41050 and Penicillium sp. SCSIO 41411, led to the isolation of 23 natural products. Five of them were identified as new ones, including two polyketide derivatives with unusual acid anhydride moieties named cordyanhydride A ethyl ester (1) and maleicanhydridane (4), and three hydroxyphenylacetic acid derivatives named stachylines H-J (10-12). Their structures were determined by detailed nuclear magnetic resonance (NMR) and mass spectroscopic (MS) analyses, while the absolute configurations were established by theoretical electronic circular dichroism (ECD) calculation. A variety of bioactive screens revealed three polyketide derivatives (1-3) with obvious antifungal activities, and 4 displayed moderate cytotoxicity against cell lines A549 and WPMY-1. Compounds 1 and 6 at 10 microM exhibited obvious inhibition against phosphodiesterase 4 (PDE4) with inhibitory ratios of 49.7% and 39.6%, respectively, while 5, 10, and 11 showed the potential of inhibiting acetylcholinesterase (AChE) by an enzyme activity test, as well as in silico docking analysis.
ESTHER : Peng_2023_Mar.Drugs_21_
PubMedSearch : Peng_2023_Mar.Drugs_21_
PubMedID: 37367652

Title : Major biotransformation of phthalic acid esters in Eisenia fetida: Mechanistic insights and association with catalytic enzymes and intestinal symbionts - Fan_2022_Environ.Int_171_107712
Author(s) : Fan X , Gu C , Jin Z , Cai J , Bian Y , Wang F , Chen H , Jiang X
Ref : Environ Int , 171 :107712 , 2022
Abstract : Phthalic acid esters (PAEs) are an important group of organic pollutants that are widely used as plasticizers in the environment. The PAEs in soil organisms are likely to be biotransformed into a variety of metabolites, and the combined toxicity of PAEs and their metabolites might be more serious than PAEs alone. However, there are only a few studies on PAE biotransformation by terrestrial animals, e.g. earthworms. Herein, the key biotransformation pathways of PAEs and their association with catalytic enzymes and intestinal symbionts in earthworms were studied using in vivo and in vitro incubation approaches. The widely distributed PAE in soil, dibutyl phthalate (DBP), was proven to be biotransformed rapidly together with apparent bioaccumulation in earthworms. The biotransformation of PAE congeners with medium or long side chains appeared to be faster compared with those with short side chains. DBP was biotransformed into butyl methyl phthalate (BMP), monobutyl phthalate (MBP), and phthalic acid (PA) through esterolysis and transesterification. Besides, the generation of small quantities of low-molecular weight metabolites via beta-oxidation, decarboxylation or ring-cleavage, was also observed, especially when the appropriate proportion of NADPH coenzyme was applied to transfer electrons for oxidases. Interestingly, the esterolysis of PAEs was mainly regulated by the cytoplasmic carboxylesterase (CarE) in earthworms, with a Michaelis constant (K(m)) of 0.416smM in the catalysis of DBP. The stronger esterolysis in non-intestinal tissues indicated that the CarE was primarily secreted by non-intestinal tissues of earthworms. Additionally, the intestinal symbiotic bacteria of earthworms could respond to PAE stress, leading to the changes in their diversity and composition. The enrichment of some genera e.g. Bacillus and Paracoccus, and the enhancement of metabolism function, e.g. amino acids, energy, lipids biosynthesis and oxidase secretion, indicated their important role in the degradation of PAEs.
ESTHER : Fan_2022_Environ.Int_171_107712
PubMedSearch : Fan_2022_Environ.Int_171_107712
PubMedID: 36577298

Title : Structural Basis for the Regiospecificity of a Lipase from Streptomyces sp. W007 - Zhao_2022_Int.J.Mol.Sci_23_5822
Author(s) : Zhao Z , Chen S , Xu L , Cai J , Wang J , Wang Y
Ref : Int J Mol Sci , 23 :5822 , 2022
Abstract : The efficiency and accuracy of the synthesis of structural lipids are closely related to the regiospecificity of lipases. Understanding the structural mechanism of their regiospecificity contributes to the regiospecific redesign of lipases for meeting the technological innovation needs. Here, we used a thermostable lipase from Streptomyces sp. W007 (MAS1), which has been recently reported to show great potential in industry, to gain an insight into the structural basis of its regiospecificity by molecular modelling and mutagenesis experiments. The results indicated that increasing the steric hindrance of the site for binding a non-reactive carbonyl group of TAGs could transform the non-specific MAS1 to a alpha-specific lipase, such as the mutants G40E, G40F, G40Q, G40R, G40W, G40Y, N45Y, H108W and T237Y (PSI > 80). In addition, altering the local polarity of the site as well as the conformational stability of its composing residues could also impact the regiospecificity. Our present study could not only aid the rational design of the regiospecificity of lipases, but open avenues of exploration for further industrial applications of lipases.
ESTHER : Zhao_2022_Int.J.Mol.Sci_23_5822
PubMedSearch : Zhao_2022_Int.J.Mol.Sci_23_5822
PubMedID: 35628632
Gene_locus related to this paper: 9actn-h0b8d4

Title : Esterase-responsive and size-optimized prodrug nanoparticles for effective intracranial drug delivery and glioblastoma treatment - Ye_2022_Nanomedicine__102581
Author(s) : Ye Z , Gao L , Cai J , Wang Y , Li Y , Tong S , Yan T , Sun Q , Qi Y , Xu Y , Jiang H , Zhang S , Zhao L , Chen Q
Ref : Nanomedicine , :102581 , 2022
Abstract : Glioblastoma multiforme (GBM) is the intracranial malignancy with the highest rates of morbidity and mortality. Chemotherapy is often ineffective against GBM due to the presence of the blood-brain barrier (BBB); however, the application of nanotechnology is expected to overcome this limitation. Poly(lactic-co-glycolic acid) (PLGA) is a degradable and nontoxic functional polymer with good biocompatibility that is widely used in the pharmaceutical industry. Previous studies have shown that the ability of PLGA nanoparticles (NPs) to penetrate the BBB is largely determined by their size; however, determination of the optimal PLGA NP size requires further research. Here, we report a tandutinib-based prodrug (proTan), which responds to the GBM microenvironment, that was combined with NPs to overcome the BBB. AMD3100-PLGA NPs loaded with proTan inhibited tumor growth and effectively prolonged the survival of tumor-bearing mice.
ESTHER : Ye_2022_Nanomedicine__102581
PubMedSearch : Ye_2022_Nanomedicine__102581
PubMedID: 35811067

Title : Nanobodies as binding-chaperones stabilize the recombinant Bombyx mori acetylcholinesterase and protect the enzyme activity in pesticide detection - Cai_2022_Enzyme.Microb.Technol_155_109992
Author(s) : Cai J , Romao E , Wu G , Li J , Li L , Wang Z , Li Y , Yang J , Shen Y , Xu Z , Muyldermans S , Wang H
Ref : Enzyme Microb Technol , 155 :109992 , 2022
Abstract : In our previous study, the recombinant type II acetylcholinesterase from Bombyx mori (rBmAChE) presented outstanding sensitivity to pesticides, which exhibited great potential in pesticides detection. However, the poor stability of rBmAChE and also the unclear mechanism of its sensitivity hindered the applications in on-site testing of pesticides residues. In this study, we constructed an immune nanobody library, in which we obtained 48 rBmAChE-specific nanobodies. Among them, Nb4 and Nb9 were verified as the most prominent enhancers of the enzyme activity and stabilizers under thermal stress, which indicated their usage as protective reagents for rBmAChE. The simultaneously addition of the two Nbs enhanced the thermal-stability of rBmAChE against exposure to 50-70 degreesC, and also remained 100% residual activity after 30 days storage at - 20 degreesC or 4 degreesC, whereas 80% and 62% at - 80 degreesC and 25 degreesC. The homologous modeling and docking of Nb4 and Nb9 to rBmAChE indicated the stabilization of Nb4 to the peripheral anion site (PAS) of rBmAChE while Nb9 protected the C-terminal structure. Substrate docking demonstrated the importance of electrostatic attraction during catalytic process, that might be enhanced by Nbs. As a result, Nb4 and Nb9 were proved to have great potential on rBmAChE applications due to their regulation on enzyme activity and protection against thermal-inactivation and long-term storage of rBmAChE.
ESTHER : Cai_2022_Enzyme.Microb.Technol_155_109992
PubMedSearch : Cai_2022_Enzyme.Microb.Technol_155_109992
PubMedID: 35114480

Title : The inhibition mechanism of polyphenols from Phyllanthus emblica Linn. fruit on acetylcholinesterase: A interaction, kinetic, spectroscopic, and molecular simulation study - Wu_2022_Food.Res.Int_158_111497
Author(s) : Wu M , Liu M , Wang F , Cai J , Luo Q , Li S , Zhu J , Tang Z , Fang Z , Wang C , Chen H
Ref : Food Res Int , 158 :111497 , 2022
Abstract : The present study aimed to investigate the inhibition mechanism of polyphenols from Phyllanthus emblica Linn. fruit (PEF, family Euphorbiaceous) on acetylcholinesterase (AChE). Interaction assay, enzyme kinetics, spectroscopic methods, and molecular simulations were performed. Results showed that myricetin, quercetin, fisetin, and gallic acid were the most active components in PEF, because of their low docking scores and strong inhibition ability on AChE with IC(50) values of 0.1974 +/- 0.0047, 0.2589 +/- 0.0131, 1.0905 +/- 0.0598 and 1.503 +/- 0.0728 mM, respectively. Among them, the results of kinetic study showed that myricetin, quercetin, and fisetin reversibly inhibited AChE in a competitive manner, while gallic acid inhibited it through a noncompetition type. The interaction assay implied that a combination of the four polyphenols at the selected concentrations manifested a synergistic inhibition effect on AChE in a mixed inhibition type. Fluorescence and UV-vis spectrophotometry revealed that the active PEF polyphenols could strongly quench the intrinsic fluorescence of AChE via a static quenching mechanism. Circular dichroism spectroscopy analysis indicated that the active PEF polyphenols gave rise to the secondary structure changes of AChE by increasing the content of alpha-helix and reducing beta-sheet and random coil conformation. The molecular dynamics simulation results validated that all the four docked polyphenol-AChE complexes were relatively stable according to their root-mean-square distance, root-mean-square fluctuations, solvent accessible surface area, radius of gyration values and hydrogen bonds evaluations during the whole simulation process. Overall, our study provides a creative insight into the further utilization of PEF polyphenols as functional components in exploring natural AChE inhibitors.
ESTHER : Wu_2022_Food.Res.Int_158_111497
PubMedSearch : Wu_2022_Food.Res.Int_158_111497
PubMedID: 35840206

Title : The Composition and Anti-Aging Activities of Polyphenol Extract from Phyllanthus emblica L. Fruit - Wu_2022_Nutrients_14_
Author(s) : Wu M , Cai J , Fang Z , Li S , Huang Z , Tang Z , Luo Q , Chen H
Ref : Nutrients , 14 : , 2022
Abstract : Phyllanthus emblica L. (PE) is commonly known as a medicine and food homologous plant, which is abundant in natural products polyphenols. In the present study, polyphenols were extracted from PE fruit by response surface method, and the anti-aging ability was determined. PE fruit polyphenols exhibited strong antioxidant capacities in scavenging free radicals, and anti-cholinesterase ability by inhibition of AChE (IC(50) 0.2186 +/- 0.0416 mg/mL) and BuChE (IC(50) 0.0542 +/- 0.0054 mg/mL) in vitro. Moreover, PE fruit polyphenols showed strong protective effect against the aging process in Caenorhabditis elegans model, including increased thermal resistance, extended lifespan by 18.53% (p < 0.05), reduced activity of AChE by 34.71% and BuChE by 45.38% (p < 0.01). This was accompanied by the enhancement in antioxidant enzymes activity of SOD by 30.74% (p < 0.05) and CAT by 8.42% (p > 0.05), while decrease in MDA level by 36.25% (p < 0.05). These properties might be interrelated with the presence of abundant flavonols and phenolic acids identified by UPLC-ESI-QTOF-MS, such as quercetin, myricetin, ellagic, gallic, and chlorogenic acids, together with their glycosides. The remarkable antioxidant and anti-aging potential of PE fruit polyphenols could be implemented in the food and pharmaceutical industry.
ESTHER : Wu_2022_Nutrients_14_
PubMedSearch : Wu_2022_Nutrients_14_
PubMedID: 35215512

Title : Toxicity, Horizontal Transfer, Physiological and Behavioral Effects of Cycloxaprid against Solenopsis invicta (Hymenoptera: Formicidae) - Zhang_2022_Pest.Manag.Sci__
Author(s) : Zhang L , Wang L , Chen J , Zhang J , He Y , Lu Y , Cai J , Chen X , Wen X , Xu Z , Wang C
Ref : Pest Manag Sci , : , 2022
Abstract : BACKGROUND: The red imported fire ant, Solenopsis invicta Buren, is a significant urban, agricultural, and medical pest with a wide distribution in the world. Surface or mound treatment using contact insecticide is one of the main methods to control S. invicta. In the present study, cycloxaprid, a newly-discovered neonicotinoid insecticide, was evaluated for S. invicta control and compared with two referent insecticides, imidacloprid and bifenthrin. RESULTS: Surfaces or sand treated with cycloxaprid, imidacloprid, or bifenthrin caused high mortality of S. invicta workers, and the action of cycloxaprid or imidacloprid was slower than bifenthrin. Like imidacloprid and bifenthrin, cycloxaprid can be horizontally transferred from corpses or live donor ants to recipient ants. In addition, cycloxaprid- or imidacloprid-treated surfaces significantly induced the activities of acetylcholinesterase (AChE) and detoxification enzymes; nevertheless, they had no significant effect on the foraging behaviors of S. invicta workers. Also, sand treated with cycloxaprid or imidacloprid did not negatively affect the digging activities of ants. Interestingly, S. invicta workers excavated significantly more sand containing 0.01 mg/kg cycloxaprid than untreated sand in the no-choice digging bioassays. In addition, extensive nesting activities (sand excavation and stacking) were observed in the flowerpots containing untreated sand or sand treated with cycloxaprid or imidacloprid. On the contrary, bifenthrin significantly reduced the foraging, digging, and nesting activities of S. invicta workers. CONCLUSION: Cycloxaprid is a slow-acting and non-repellent insecticide against S. invicta workers, and its contact and horizontal toxicities are slightly higher than imidacloprid. This article is protected by copyright. All rights reserved.
ESTHER : Zhang_2022_Pest.Manag.Sci__
PubMedSearch : Zhang_2022_Pest.Manag.Sci__
PubMedID: 35192738

Title : Preparation of a Bombyx mori acetylcholinesterase enzyme reagent through chaperone protein disulfide isomerase co-expression strategy in Pichia pastoris for detection of pesticides - Li_2021_Enzyme.Microb.Technol_144_109741
Author(s) : Li J , Cai J , Ma M , Li L , Lu L , Wang Y , Wang C , Yang J , Xu Z , Yao M , Shen X , Wang H
Ref : Enzyme Microb Technol , 144 :109741 , 2021
Abstract : The cholinesterase-based spectrophotometric methods for detection of organophosphate pesticides (OPs) and carbamate pesticides (CPs) have been proposed as a good choice for their high efficiency, simplicity and low cost. The enzyme, as a core reagent, is of great importance for the developed method. In this study, a protein disulfide isomerase (PDI) co-expression strategy in Pichia pastoris was employed to enhance the yield of recombinant Bombyx mori acetylcholinesterase 2 (rBmAChE2). Subsequently, the prepared enzyme reagent was used to detect the pesticides in real samples. The results showed that the co-expression of rBmAChE2 with PDI increased the enzyme activity of the supernatant and the yield of purified rBmAChE2 up to 60 U/mL and 6 mg/L respectively, both almost 5-fold higher than those of original recombinant strain. In addition, 5 g/L gelatin reagent could help to preserve nearly 90% of the rBmAChE2 activity for 90 days in 4 degreesC and the limits of detections (LODs) of the rBmAChE2-based assay for 20 kinds of OPs or CPs ranged from 0.010 to 2.725 mg/kg, which were lower than most of indexes present in current Chinese National Standard (GB/T 5009.199-2003) or the maximum residue limits (GB 2763-2019). Furthermore, the detection results of 23 vegetable samples were verified by the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method, which indicated that the rBmAChE2-based assay in this work is suitable for pesticide residues rapid detection.
ESTHER : Li_2021_Enzyme.Microb.Technol_144_109741
PubMedSearch : Li_2021_Enzyme.Microb.Technol_144_109741
PubMedID: 33541576
Gene_locus related to this paper: boomi-ACHE2

Title : Mechanistic insights into primary biotransformation of diethyl phthalate in earthworm and significant SOD inhibitory effect of esterolytic products - Fan_2021_Chemosphere_288_132491
Author(s) : Fan X , Gu C , Cai J , Zhong M , Bian Y , Jiang X
Ref : Chemosphere , 288 :132491 , 2021
Abstract : Phthalic acid esters (PAEs) are used as plasticizer or modifier in artificially-manufactured products. Though the rapid biotransformation of phthalates in microbes and plants have been well documented, it is less studied yet in terrestrial animals, e.g. earthworm. In this study, the major biotransformation of diethyl phthalate (DEP) in Eisenia fetida was illustrated using in vitro incubation of earthworm crude enzymes. DEP could be substantially biotransformed into phthalate monoester (MEP) and a small amount of phthalic acid (PA) through esterolysis, which was verified to be driven by endogenous carboxylesterase. Despite the inferior contribution, the oxidation of DEP might also occur under the initiated electron transfer by NADPH coenzyme. The dominant metabolite MEP showed a higher inhibition of superoxide dismutase (SOD) activity than DEP with EC(50) of 0.0082 +/- 0.0016 mmol/L, so the higher ecological risks of MEP would be marked. The inhibition effect of PA was validated to be even stronger than MEP though it was slightly generated. The direct binding interaction with SOD was proved to be an important molecular event for regulation of SOD activity. Besides the static quenching mechanism, the caused conformational changes including despiralization of alpha-helix and spatial reorientation of tryptophan were spectrally believed to affect binding and underlie inhibition efficiency of SOD activity.
ESTHER : Fan_2021_Chemosphere_288_132491
PubMedSearch : Fan_2021_Chemosphere_288_132491
PubMedID: 34624352

Title : Enhanced Secretory Expression and Surface Display Level of Bombyx mori Acetylcholinesterase 2 by Pichia pastoris Based on Codon Optimization Strategy for Pesticides Setection - Li_2021_Appl.Biochem.Biotechnol__
Author(s) : Li J , Xie X , Cai J , Wang H , Yang J
Ref : Appl Biochem Biotechnol , : , 2021
Abstract : The cholinesterase-based spectrophotometric assay, also called enzyme inhibition method, is a good choice for rapid detection of organophosphate pesticides (OPs) and carbamate pesticides (CPs). Obviously, the cholinesterase is the core reagent in enzyme inhibition method. In our previous work, a recombinant acetylcholinesterase 2 from Bombyx mori (rBmAChE2) was expressed in yeast successfully and exhibited great sensitivity. However, the yield of rBmAChE2 is not desirable. In this study, a codon optimization strategy was employed to enhance the yield of rBmAChE2 in Pichia pastoris GS115. Results showed that by replacing 6 key rare codons and increasing the percentage of bases G and C up to 46.85%, codon adaptation index (CAI) of Bombyx mori acetylcholinesterase 2 (bmace2) gene was improved from 0.70 to 0.81. After being transformed into Pichia pastoris GS115 via electroporation, the expression transformant can produce 139.7 U/mL secretory codon-optimized rBmAChE2 (opt-rBmAChE2) in the culture supernatant, 3.62 times higher than that of strain bearing the wild-type bmace2 gene. Meanwhile, opt-rBmAChE2 displayed on the yeast surface was up to 2280.02 U/g, 2.8 times higher than wild-type displayed rBmAChE2. In addition, either secretory or surface-displayed opt-rBmAChE2 maintained the similar sensitivities to the wild-type rBmAChE2 for tested inhibitors. Furthermore, the detection limits of the opt-rBmAChE2-based enzyme inhibition method for 10 kinds of OPs or CPs (0.01-2.69 mg/kg) were lower than most of the indexes present in current standard method (GB/T 5009.199-2003) or the maximum residue limits (GB 2763-2019) in China. The results might contribute to the utilization of rBmAChE2 for pesticide residue screening detection in practice.
ESTHER : Li_2021_Appl.Biochem.Biotechnol__
PubMedSearch : Li_2021_Appl.Biochem.Biotechnol__
PubMedID: 34160750

Title : Bioactive Polyketide and Diketopiperazine Derivatives from the Mangrove-Sediment-Derived Fungus Aspergillus sp. SCSIO41407 - Cai_2021_Molecules_26_
Author(s) : Cai J , Chen C , Tan Y , Chen W , Luo X , Luo L , Yang B , Liu Y , Zhou X
Ref : Molecules , 26 : , 2021
Abstract : Ten polyketide derivatives (1-10), including a new natural product named (E)-2,4-dihydroxy-3-methyl-6-(2-oxopent-3-en-1-yl) benzaldehyde (1), and five known diketopiperazines (11-15), were isolated from the mangrove-sediment-derived fungus Aspergillus sp. SCSIO41407. The structures of 1-15 were determined via NMR and MS spectroscopic analysis. In a variety of bioactivity screening, 3 showed weak cytotoxicity against the A549 cell line, and 2 exhibited weak antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Compounds 3, 5, and 6 showed inhibition against acetylcholinesterase (AChE) with IC(50) values of 23.9, 39.9, and 18.6 microM. Compounds 11, 12, and 14 exhibited obvious inhibitory activities of lipopolysaccharide (LPS)-induced nuclear factor-kappaB (NF-kappaB) with IC(50) values of 19.2, 20.9, and 8.7 microM, and they also suppressed RANKL-induced osteoclast differentiation in bone marrow macrophages cells (BMMCs), with the concentration of 5 microM. In silico molecular docking with AChE and NF-kappaB p65 protein were also performed to understand the inhibitory activities, and 1, 11-14 showed obvious protein/ligand-binding effects to the NF-kappaB p65 protein.
ESTHER : Cai_2021_Molecules_26_
PubMedSearch : Cai_2021_Molecules_26_
PubMedID: 34443439

Title : Protein tyrosine phosphatase 1B (PTP1B) inhibitorsfrom the deep-sea fungus Penicillium chrysogenum SCSIO 07007 - Han_2020_Bioorg.Chem_96_103646
Author(s) : Han W , Cai J , Zhong W , Xu G , Wang F , Tian X , Zhou X , Liu Q , Liu Y , Wang J
Ref : Bioorg Chem , 96 :103646 , 2020
Abstract : Three new compounds, including two new 3,4,6-trisubstituted alpha-pyrone derivatives, chrysopyrones A and B (1 and 2), and one new indolyl diketopiperazine derivative, penilline C (3), along with twelve known compounds (4-15), were isolated and identified from the fungus Penicillium chrysogenum SCSIO 07007, separated from deep-sea hydrothermal vent environment sample collected from the Western Atlantic. Their structures and absolute configurations were determined by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. All of the isolated compounds (1-15) were evaluated for their cytotoxic, antibacterial activities and enzyme inhibitory activities against acetylcholinesterase (AChE), alpha-glycosidase, and protein tyrosine phosphatase 1B (PTP1B). Among them, new compounds chrysopyrones A and B (1 and 2) displayed obvious inhibitory activities against PTP1B with IC50 values of 9.32 and 27.8 mug/mL, respectively. Furthermore, molecular docking was performed to investigate the inside perspective of the action in PTP1B enzyme.
ESTHER : Han_2020_Bioorg.Chem_96_103646
PubMedSearch : Han_2020_Bioorg.Chem_96_103646
PubMedID: 32036160

Title : Long noncoding RNA ABHD11-AS1 functions as a competing endogenous RNA to regulate papillary thyroid cancer progression by miR-199a-5p\/SLC1A5 axis - Zhuang_2019_Cell.Death.Dis_10_620
Author(s) : Zhuang X , Tong H , Ding Y , Wu L , Cai J , Si Y , Zhang H , Shen M
Ref : Cell Death Dis , 10 :620 , 2019
Abstract : With the increasing incidence of papillary thyroid cancer (PTC), more attention has been paid to exploring the mechanism of PTC initiation and progression. In addition, ectopic expression of long noncoding RNAs (lncRNAs) is reported to play a pivotal role in multiple human cancers. Based on these findings, we examined lncRNA ABHD11 antisense RNA 1 (ABHD11-AS1) expression and its clinical significance, biological function and mechanism in PTC. First, we analyzed thyroid ABHD11-AS1 expression in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Then, qRT-PCR was applied to detect the expression in paired PTC tissues and adjacent normal tissues, as well as in PTC cell lines (TPC-1 and K-1) and a normal thyroid follicular epithelium cell line (Nthy-ori3-1). In addition, we validated the relationship between ABHD11-AS1 expression and clinicopathological features by the Pearson X(2) test. The oncogenic role of ABHD11-AS1 and its regulation of miR-199a-5p in PTC were examined by biological assays. Finally, bioinformatics analysis and mechanism assays were used to elucidate the underlying mechanism. We found that ABHD11-AS1 was remarkably overexpressed in PTC, and high expression was related to tumor size, lymph node metastasis, extrathyroidal extension and advanced TNM stage. Moreover, ABHD11-AS1 enhanced the abilities of cell proliferation, migration, and invasion, inhibited apoptosis in vitro, promoted tumorigenesis in vivo via sponging miR-199a-5p and then induced SLC1A5 activation. In addition, rescue assays were performed to confirm the ABHD11-AS1/miR-199a-5p/SLC1A5 axis. Taken together, the data show that ABHD11-AS1 acts as a competing endogenous RNA (ceRNA) to exert malignant properties in PTC through the miR-199a-5p/SLC1A5 axis. Therefore, our study may shed light on PTC diagnosis and therapies.
ESTHER : Zhuang_2019_Cell.Death.Dis_10_620
PubMedSearch : Zhuang_2019_Cell.Death.Dis_10_620
PubMedID: 31409775
Gene_locus related to this paper: human-ABHD11

Title : Design, synthesis and evaluation of a novel metal chelator as multifunctional agents for the treatment of Alzheimer's disease - Wang_2019_Bioorg.Chem_87_720
Author(s) : Wang Y , Yang Y , Hong KH , Ning Y , Yu P , Ren J , Ji M , Cai J
Ref : Bioorg Chem , 87 :720 , 2019
Abstract : A series of compounds following the lead compounds including deferasirox and tacrine were designed, synthesized and evaluated as multifunctional agents against Alzheimer's disease (AD). In vitro studies showed that most synthesized compounds exhibited good multifunctional activities in inhibiting acetylcholinesterase (bAChE), and chelating metal ions. Especially, compound TDe demonstrated significant metal chelating property, a moderate acetylcholinesterase (AChE) inhibitory activity and an antioxidant activity. Results from the molecular modeling indicated that TD compounds were mixed-type inhibitor, binding simultaneously to the catalytic anionic site (CAS) and the peripheral anionic site (PAS) of TcAChE. Moreover, TDe showed a low cytotoxicity but a good protective activity against the injury caused by H2O2. These results suggest that TD compounds might be considered as attractive multi-target cholinesterase inhibitor and will play important roles in the treatment of AD.
ESTHER : Wang_2019_Bioorg.Chem_87_720
PubMedSearch : Wang_2019_Bioorg.Chem_87_720
PubMedID: 30954836

Title : Guided Evolution of Recombinant Bombyx mori Acetylcholinesterase II by Homology Modeling to Change Pesticide Sensitivity -
Author(s) : Cai J , Wang B , Li J , Chen Z , Rao M , Muyldermans S , Hua X , Xie X , Wang H , Yang J , Xu Z , Shen Y , Sun Y
Ref : Int J Mol Sci , 19 : , 2018
PubMedID: 30373269

Title : Multifunctional Compound AD-35 Improves Cognitive Impairment and Attenuates the Production of TNF-alpha and IL-1beta in an Abeta25-35-induced Rat Model of Alzheimer's Disease - Li_2017_J.Alzheimers.Dis_56_1403
Author(s) : Li L , Xu S , Liu L , Feng R , Gong Y , Zhao X , Li J , Cai J , Feng N , Wang L , Wang X , Peng Y
Ref : J Alzheimers Dis , 56 :1403 , 2017
Abstract : The dyshomeostasis of transition metal ions, accumulation of amyloid-beta (Abeta) senile plaques and neuroinflammatory response found in the brain of patients with Alzheimer's disease (AD) have been suggested to be involved in AD pathogenesis. Novel compounds capable of targeting metal-Abeta species and neuroinflammation would be valuable. AD-35 is such a patented small-molecule compound derived from innovative modification of the chemical structure of donepezil. This compound could moderately inhibit acetylcholinesterase and metal-induced Abeta aggregation in vitro and showed disassembly of Abeta aggregates. The effects of AD-35 on cognitive impairments and neuroinflammatory changes caused by intracerebroventricular injection of Abeta25-35 were studied in rats. Compared to sham group, Abeta25-35 injection significantly led to learning and memory deficits, astrocyte activation, and pro-inflammatory cytokines releases (TNF-alpha and IL-1beta). Further studies indicated that the phosphorylation of extracellular signal-regulated kinase was involved in astrocyte activation and pro-inflammatory cytokines production. Oral administration of AD-35 could markedly attenuate Abeta25-35 injection-induced astrocyte activation, pro-inflammatory cytokines TNF-alpha and IL-1beta release, and memory deficits. On the contrary, donepezil only showed inhibition of IL-1beta production, but failed to block astrocyte activation and TNF-alpha production. These results showed that AD-35 would be a novel multi-mechanism drug for the prevention and/or treatment of AD.
ESTHER : Li_2017_J.Alzheimers.Dis_56_1403
PubMedSearch : Li_2017_J.Alzheimers.Dis_56_1403
PubMedID: 28157092

Title : A visible light photoelectrochemical biosensor coupling enzyme-inhibition for organophosphates monitoring based on a dual-functional Cd(0.5)Zn(0.5)S-reduced graphene oxide nanocomposite - Liu_2014_Analyst_139_1121
Author(s) : Liu Q , Cai J , Huan J , Dong X , Wang C , Qiu B , Wang K
Ref : Analyst , 139 :1121 , 2014
Abstract : A novel visible light photoelectrochemical (PEC) platform coupled with enzyme-inhibition for rapid and sensitive determination of organophosphates (OPs) was constructed based on a dual-functional Cd0.5Zn0.5S-reduced graphene oxide (Cd0.5Zn0.5S-rGO) nanocomposite. Due to the inherent biocompatibility of the Cd0.5Zn0.5S-rGO nanocomposite, acetylcholinesterase (AChE) immobilized on the Cd0.5Zn0.5S-rGO modified electrode can hydrolyze acetylthiocholine chloride into thiocholine, which could increase the photocurrent of the enzyme electrode, and the further inhibition of OPs on the enzyme electrode could decrease the photocurrent response. Based on the notable change in the PEC response of the AChE-Cd0.5Zn0.5S-rGO modified electrode and using Dursban as a model, a simple and effective way for PEC monitoring of OPs is proposed, which showed a wide linear range of 0.001-1 mug mL(-1) with a low detection limit of 0.3 ng mL(-1) (S/N = 3). Moreover, the biosensor was successfully challenged with water samples, demonstrating a new method for rapid and sensitive screening/evaluating exposure to organophosphorus pesticides and other hazardous substances.
ESTHER : Liu_2014_Analyst_139_1121
PubMedSearch : Liu_2014_Analyst_139_1121
PubMedID: 24416761

Title : The genomes of four tapeworm species reveal adaptations to parasitism - Tsai_2013_Nature_496_57
Author(s) : Tsai IJ , Zarowiecki M , Holroyd N , Garciarrubio A , Sanchez-Flores A , Brooks KL , Tracey A , Bobes RJ , Fragoso G , Sciutto E , Aslett M , Beasley H , Bennett HM , Cai J , Camicia F , Clark R , Cucher M , De Silva N , Day TA , Deplazes P , Estrada K , Fernandez C , Holland PW , Hou J , Hu S , Huckvale T , Hung SS , Kamenetzky L , Keane JA , Kiss F , Koziol U , Lambert O , Liu K , Luo X , Luo Y , Macchiaroli N , Nichol S , Paps J , Parkinson J , Pouchkina-Stantcheva N , Riddiford N , Rosenzvit M , Salinas G , Wasmuth JD , Zamanian M , Zheng Y , Cai X , Soberon X , Olson PD , Laclette JP , Brehm K , Berriman M
Ref : Nature , 496 :57 , 2013
Abstract : Tapeworms (Cestoda) cause neglected diseases that can be fatal and are difficult to treat, owing to inefficient drugs. Here we present an analysis of tapeworm genome sequences using the human-infective species Echinococcus multilocularis, E. granulosus, Taenia solium and the laboratory model Hymenolepis microstoma as examples. The 115- to 141-megabase genomes offer insights into the evolution of parasitism. Synteny is maintained with distantly related blood flukes but we find extreme losses of genes and pathways that are ubiquitous in other animals, including 34 homeobox families and several determinants of stem cell fate. Tapeworms have specialized detoxification pathways, metabolism that is finely tuned to rely on nutrients scavenged from their hosts, and species-specific expansions of non-canonical heat shock proteins and families of known antigens. We identify new potential drug targets, including some on which existing pharmaceuticals may act. The genomes provide a rich resource to underpin the development of urgently needed treatments and control.
ESTHER : Tsai_2013_Nature_496_57
PubMedSearch : Tsai_2013_Nature_496_57
PubMedID: 23485966
Gene_locus related to this paper: echgr-k4epc5 , hymmi-a0a068x9f5 , echmu-u6hbw4 , echgr-w6ugl0 , echmu-u6hr32 , echmu-a0a068y5f4 , hymmi-a0a068xag4 , hymmi-a0a068x810 , hymmi-a0a068xcc1 , echmu-a0a068yf54 , echgr-a0a068wxj3 , echgr-a0a068wgw1 , hymmi-a0a068xge7 , hymmi-a0a068x8h9 , echmu-a0a068y747 , hymmi-a0a068xgj7 , echgr-a0a068wl60

Title : Molecular mechanism of inflammatory response in mouse liver caused by exposure to CeCl3 - Li_2013_Environ.Toxicol_28_349
Author(s) : Li N , Cheng J , Cheng Z , Hu R , Cai J , Gao G , Cui Y , Wang L , Hong F
Ref : Environ Toxicol , 28 :349 , 2013
Abstract : To investigate the molecular mechanism of inflammatory response in the mouse liver caused by exposure to CeCl3 , we measured the liver indices, and cerium content, evaluated the liver histopathological section, detected serum biochemical parameters of liver function, and the immunoglobulin M (IgM) content, analyzed the liver mRNA and protein expression levels of Toll-like receptor 2, 4 (TLR2, TLR4), and inflammatory cytokines in liver using real-time quantitative reverse transcriptase polymerase chain reaction and enzyme-linked immunosorbent assay. The results showed that exposure to CeCl3 decreased body weight and caused cerium accumulation in the mouse liver and histopathological changes of liver (such as inflammatory cell infiltration). Furthermore, biochemical assays suggested that CeCl3 could promote the activities of alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, lactate dehydrogenase, pseudocholinesterase, and leucine aminopeptidase, decrease serum IgM, upregulate the levels of TLR2, TLR4, nuclear factor-kappaB (NF-kappaB), NF-kappaBp52, NF-kappaBp65, NF-kappaB-inducing kinase (NIK), IkappaB kinase alpha (IKK-alpha), IkappaB kinase beta (IKK-beta), and tumor necrosis factor-alpha (TNF-alpha) expression, and suppress NF-kappaB-inhibiting factor (IkappaB) and interleukin-2 (IL-2) expression in liver. Taken together, the inflammation of mice liver caused by exposure to CeCl3 might be closely associated with the alteration of inflammatory cytokine expressions in the mouse liver, the signal-transducing events happening in CeCl3 -induced macrophages of liver sequentially might occur via activation of TLRs-->TNF-alpha-->NIK-->IkappaB kinase (including IKK1, IKK2)-->NF-kappaB (including NF-kappaBP52, NF-kappaBP65)--> inflammation. (c) 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.
ESTHER : Li_2013_Environ.Toxicol_28_349
PubMedSearch : Li_2013_Environ.Toxicol_28_349
PubMedID: 21656643

Title : Complete Genome Sequence of an Oral Commensal, Streptococcus oligofermentans Strain AS 1.3089 - Tong_2013_Genome.Announc_1_
Author(s) : Tong H , Shang N , Liu L , Wang X , Cai J , Dong X
Ref : Genome Announc , 1 : , 2013
Abstract : Streptococcus oligofermentans, an oral commensal, inhibits the growth of the dental caries pathogen Streptococcus mutans by producing large amounts of hydrogen peroxide. Therefore, it can be a potential probiotic for oral health. Here we report the complete genome sequence of S. oligofermentans strain AS 1.3089.
ESTHER : Tong_2013_Genome.Announc_1_
PubMedSearch : Tong_2013_Genome.Announc_1_
PubMedID: 23788543
Gene_locus related to this paper: strcr-n0c7c9

Title : Chrysin attenuates allergic airway inflammation by modulating the transcription factors T-bet and GATA-3 in mice - Du_2012_Mol.Med.Rep_6_100
Author(s) : Du Q , Gu X , Cai J , Huang M , Su M
Ref : Mol Med Rep , 6 :100 , 2012
Abstract : Chrysin, a flavonoid obtained from various natural sources, has been reported to possess anti-inflammatory, antitumor, antioxidant and anti-allergic activities. However, its anti-inflammatory and immunoregulatory activities in asthma animal models are poorly understood. In the present study, we examined the effects of chrysin on airway inflammation and the possible mechanisms through which it acts in a murine model of allergic asthma. BALB/c mice sensitized and challenged to ovalbumin (OVA) were administered intragastrically with chrysin at a dose of 50 mg/kg daily. Chrysin significantly suppressed OVA-induced airway hyperresponsiveness (AHR) to acetylcholine chloride (Ach). Chrysin administration significantly inhibited the total inflammatory cell and eosinophil counts in bronchoalveolar lavage fluid (BALF) and total immunoglobulin E (IgE) levels in serum. Histological examination of lung tissue demonstrated that chrysin significantly attenuated allergen-induced lung eosinophilic inflammation and mucus-producing goblet cells in the airway. In addition, chrysin triggered a switch of the immune response to allergens towards a T-helper type 1 (Th1) profile by modulating the transcription factors T-bet and GATA-3 in allergic mice. These data suggest that chrysin exhibits anti-inflammatory and immunoregulatory properties and provides new insights into the immunopharmacological role of chrysin in terms of its effects in a murine model of asthma.
ESTHER : Du_2012_Mol.Med.Rep_6_100
PubMedSearch : Du_2012_Mol.Med.Rep_6_100
PubMedID: 22552848

Title : Donepezil attenuates hippocampal neuronal damage and cognitive deficits after global cerebral ischemia in gerbils - Min_2012_Neurosci.Lett_510_29
Author(s) : Min D , Mao X , Wu K , Cao Y , Guo F , Zhu S , Xie N , Wang L , Chen T , Shaw C , Cai J
Ref : Neuroscience Letters , 510 :29 , 2012
Abstract : Decreased cerebral blood flow causes cognitive impairments and neuronal injury in vascular dementia. In the present study, we reported that donepezil, a cholinesterase inhibitor, improved transient global cerebral ischemia-induced spatial memory impairment in gerbils. Treatment with 5mg/kg of donepezil for 21 consecutive days following a 10-min period of ischemia significantly inhibited delayed neuronal death in the hippocampal CA1 region. In Morris water maze test, memory impairment was significantly improved by donepezil treatment. Western blot analysis showed that donepezil treatment prevented reductions in p-CaMKII and p-CREB protein levels in the hippocampus. These results suggest that donepezil attenuates the memory deficit induced by transient global cerebral ischemia and this neuroprotection may be associated with the phosphorylation of CaMKII and CERB in the hippocampus.
ESTHER : Min_2012_Neurosci.Lett_510_29
PubMedSearch : Min_2012_Neurosci.Lett_510_29
PubMedID: 22240104

Title : Fervidobacterium changbaicum Lip1: identification, cloning, and characterization of the thermophilic lipase as a new member of bacterial lipase family V - Cai_2011_Appl.Microbiol.Biotechnol_89_1463
Author(s) : Cai J , Xie Y , Song B , Wang Y , Zhang Z , Feng Y
Ref : Applied Microbiology & Biotechnology , 89 :1463 , 2011
Abstract : A novel lipase gene encoded 315 amino acid residues was obtained using lipase-prospecting primers and genome walking from hyperthermophilic bacterium Fervidobacterium changbaicum CBS-1. Sequence alignment and phylogenetic analysis revealed this novel lipase is a new member of bacterial lipase family V. The recombinant enzyme F. changbaicum lipase 1 (FCLip1) showed maximum activity at 78 degreesC and pH 7.8. It displayed extreme thermostability at 70 degreesC and was also stable across a wide pH range from 6.0 to 12.0. Kinetic study demonstrated FCLip1 preferentially hydrolyzed middle-length acyl chains, especially p-nitrophenyl caprate and tricaprylin. With p-nitrophenyl caprate as a substrate, the enzyme exhibited a K(m) and k(cat) of 4.67 microM and 22.7/s, respectively. In addition, FCLip1 was resistant to various detergents and organic solvents. This enzyme is the first reported thermophilic lipase from bacterial family Thermotogaceae. Its extreme stability with respect to temperature and pH, along with its triglyceride hydrolysis activity, indicate that FCLip1 has high potential for future application.
ESTHER : Cai_2011_Appl.Microbiol.Biotechnol_89_1463
PubMedSearch : Cai_2011_Appl.Microbiol.Biotechnol_89_1463
PubMedID: 21046373
Gene_locus related to this paper: 9them-a1yv97

Title : Complete genome sequence of the pathogenic bacterium Riemerella anatipestifer strain RA-GD - Yuan_2011_J.Bacteriol_193_2896
Author(s) : Yuan J , Liu W , Sun M , Song S , Cai J , Hu S
Ref : Journal of Bacteriology , 193 :2896 , 2011
Abstract : Riemerella anatipestifer is a well-described pathogen of waterfowl and other avian species which can cause a great loss to the poultry industry. Here we obtained the complete genome sequence of R. anatipestifer strain RA-GD, which was isolated from an infected duck in Guangzhou, China, and was cultivated in our laboratory.
ESTHER : Yuan_2011_J.Bacteriol_193_2896
PubMedSearch : Yuan_2011_J.Bacteriol_193_2896
PubMedID: 21441509
Gene_locus related to this paper: riean-e6jh69 , riean-e6jim0

Title : Acetylcholinesterase biosensor design based on carbon nanotube-encapsulated polypyrrole and polyaniline copolymer for amperometric detection of organophosphates - Du_2010_Biosens.Bioelectron_25_2503
Author(s) : Du D , Ye X , Cai J , Liu J , Zhang A
Ref : Biosensors & Bioelectronics , 25 :2503 , 2010
Abstract : A simple method to immobilize acetylcholinesterase (AChE) on polypyrrole (PPy) and polyaniline (PANI) copolymer doped with multi-walled carbon nanotubes (MWCNTs) was proposed. The synthesized PAn-PPy-MWCNTs copolymer presented a porous and homogeneous morphology which provided an ideal size to entrap enzyme molecules. Due to the biocompatible microenvironment provided by the copolymer network, the obtained composite was devised for AChE attachment, resulting in a stable AChE biosensor for screening of organophosphates (OPs) exposure. MWCNTs promoted electron-transfer reactions at a lower potential and catalyzed the electro-oxidation of thiocholine, thus increasing detection sensitivity. Based on the inhibition of OPs on the AChE activity, using malathion as a model compound, the inhibition of malathion was proportional to its concentration ranging from 0.01 to 0.5 microg/mL and from 1 to 25 microg/mL, with a detection limit of 1.0 ng/mL. The developed biosensor exhibited good reproducibility and acceptable stability, thus providing a new promising tool for analysis of enzyme inhibitors.
ESTHER : Du_2010_Biosens.Bioelectron_25_2503
PubMedSearch : Du_2010_Biosens.Bioelectron_25_2503
PubMedID: 20472422

Title : The sequence and de novo assembly of the giant panda genome - Li_2010_Nature_463_311
Author(s) : Li R , Fan W , Tian G , Zhu H , He L , Cai J , Huang Q , Cai Q , Li B , Bai Y , Zhang Z , Zhang Y , Wang W , Li J , Wei F , Li H , Jian M , Nielsen R , Li D , Gu W , Yang Z , Xuan Z , Ryder OA , Leung FC , Zhou Y , Cao J , Sun X , Fu Y , Fang X , Guo X , Wang B , Hou R , Shen F , Mu B , Ni P , Lin R , Qian W , Wang G , Yu C , Nie W , Wang J , Wu Z , Liang H , Min J , Wu Q , Cheng S , Ruan J , Wang M , Shi Z , Wen M , Liu B , Ren X , Zheng H , Dong D , Cook K , Shan G , Zhang H , Kosiol C , Xie X , Lu Z , Li Y , Steiner CC , Lam TT , Lin S , Zhang Q , Li G , Tian J , Gong T , Liu H , Zhang D , Fang L , Ye C , Zhang J , Hu W , Xu A , Ren Y , Zhang G , Bruford MW , Li Q , Ma L , Guo Y , An N , Hu Y , Zheng Y , Shi Y , Li Z , Liu Q , Chen Y , Zhao J , Qu N , Zhao S , Tian F , Wang X , Wang H , Xu L , Liu X , Vinar T , Wang Y , Lam TW , Yiu SM , Liu S , Huang Y , Yang G , Jiang Z , Qin N , Li L , Bolund L , Kristiansen K , Wong GK , Olson M , Zhang X , Li S , Yang H
Ref : Nature , 463 :311 , 2010
Abstract : Using next-generation sequencing technology alone, we have successfully generated and assembled a draft sequence of the giant panda genome. The assembled contigs (2.25 gigabases (Gb)) cover approximately 94% of the whole genome, and the remaining gaps (0.05 Gb) seem to contain carnivore-specific repeats and tandem repeats. Comparisons with the dog and human showed that the panda genome has a lower divergence rate. The assessment of panda genes potentially underlying some of its unique traits indicated that its bamboo diet might be more dependent on its gut microbiome than its own genetic composition. We also identified more than 2.7 million heterozygous single nucleotide polymorphisms in the diploid genome. Our data and analyses provide a foundation for promoting mammalian genetic research, and demonstrate the feasibility for using next-generation sequencing technologies for accurate, cost-effective and rapid de novo assembly of large eukaryotic genomes.
ESTHER : Li_2010_Nature_463_311
PubMedSearch : Li_2010_Nature_463_311
PubMedID: 20010809
Gene_locus related to this paper: ailme-ABH15 , ailme-ACHE , ailme-BCHE , ailme-d2gtv3 , ailme-d2gty9 , ailme-d2gu87 , ailme-d2gu97 , ailme-d2gve7 , ailme-d2gwu1 , ailme-d2gx08 , ailme-d2gyt0 , ailme-d2gz36 , ailme-d2gz37 , ailme-d2gz38 , ailme-d2gz39 , ailme-d2gz40 , ailme-d2h5r9 , ailme-d2h7b7 , ailme-d2h9c9 , ailme-d2h794 , ailme-d2hau7 , ailme-d2hau8 , ailme-d2hcd9 , ailme-d2hdi6 , ailme-d2heu6 , ailme-d2hga4 , ailme-d2hqw5 , ailme-d2hs98 , ailme-d2hsx4 , ailme-d2hti6 , ailme-d2htv3 , ailme-d2htz6 , ailme-d2huc7 , ailme-d2hwj8 , ailme-d2hwy7 , ailme-d2hxm1 , ailme-d2hyc8 , ailme-d2hyv2 , ailme-d2hz11 , ailme-d2hza3 , ailme-d2hzr4 , ailme-d2i1l4 , ailme-d2i2g8 , ailme-g1l7m3 , ailme-g1lu36 , ailme-g1m769 , ailme-g1mc29 , ailme-g1mdj8 , ailme-g1mdr5 , ailme-g1mfp4 , ailme-g1mfx5 , ailme-g1lj41 , ailme-g1lm28 , ailme-g1l3u1 , ailme-g1l7l1 , ailme-g1m5i3 , ailme-g1l2f6 , ailme-g1lji5 , ailme-g1lqk3 , ailme-g1l8s9 , ailme-d2h717 , ailme-d2h718 , ailme-d2h719 , ailme-d2h720 , ailme-g1m5v0 , ailme-g1m5y7 , ailme-g1lkt7 , ailme-g1l2a1 , ailme-g1lsc8 , ailme-g1lrp4 , ailme-d2gv02 , ailme-g1mik5 , ailme-g1ljr1 , ailme-g1lxw7 , ailme-d2h8b5 , ailme-d2h2r2 , ailme-d2h9w7 , ailme-g1meh3 , ailme-g1m719

Title : Acetylcholinesterase biosensor based on gold nanoparticles and cysteamine self assembled monolayer for determination of monocrotophos - Du_2009_J.Nanosci.Nanotechnol_9_2368
Author(s) : Du D , Chen W , Cai J , Zhang J , Tu H , Zhang A
Ref : J Nanosci Nanotechnol , 9 :2368 , 2009
Abstract : In this paper, a simple method for immobilization of acetylcholinesterase (AChE) on cysteamine assembled glassy carbon electrode coupled with gold nanoparticles (GNPs) was proposed and thus a sensitive, fast and stable amperometric biosensor for quantitative determination of monocrotophos was developed. The fabrication procedure was characterized by cyclic voltammetry, electrochemical impedance spectroscopy and contact angles. The presence of GNPs not only led to an increased effective surface to provide a sufficient amount of sites for binding enzyme, but also promoted electron transfer reactions and catalyzed the electro-oxidation of thiocholine, thus amplifying the detection sensitivity. Due to the notable decrease in voltammetric signal of the immobilized AChE, a simple method for determination of monocrotophos was established. The inhibition of monocrotophos was proportional to its concentration in two ranges, from 0.5 to 10 ng mL(-1) and from 10 to 600 ng mL(-1), with a detection limit lower than 0.3 ng mL(-1). The constructed biosensor processing prominent characteristics and performance such as good precision and reproducibility, acceptable stability and accuracy, fast response and low detection limit has potential application in detection of toxic compounds.
ESTHER : Du_2009_J.Nanosci.Nanotechnol_9_2368
PubMedSearch : Du_2009_J.Nanosci.Nanotechnol_9_2368
PubMedID: 19437977

Title : Immobilization of acetylcholinesterase based on the controllable adsorption of carbon nanotubes onto an alkanethiol monolayer for carbaryl sensing - Du_2008_Analyst_133_1790
Author(s) : Du D , Wang M , Cai J , Tao Y , Tu H , Zhang A
Ref : Analyst , 133 :1790 , 2008
Abstract : A simple method to immobilize acetylcholinesterase (AChE) on the controllable adsorption of multiwalled carbon nanotubes (MWCNTs) onto an alkanethiol self-assembled monolayer (C(6)H(13)SH SAM) modified Au electrode was proposed. The surface coverage of the MWCNTs was readily controlled by adjusting the immersion time for the adsorption of the MWCNTs. Atomic force microscopy (AFM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to monitor these controllable fabrication processes. The MWCNTs adsorbed onto the SAM surface substantially restores the heterogeneous electron transfer between the bare Au electrode and the redox system in the solution phase that is almost totally blocked by the SAM of C(6)H(13)SH, and as a result, the prepared MWCNT-SAM-modified electrode possesses good electrode reactivity without a remarkable barrier to heterogeneous electron transfer. Due to the inherent conductive properties of MWCNTs, the immobilized AChE exhibited high affinity to its substrate and produced a detectable and fast response. Thus, a sensitive, efficient and stable amperometric sensor for quantitative determination of carbaryl was developed. The inhibition of carbaryl was proportional to its concentration ranging from 0.001 to 1 microg mL(-1) and 2 to 15 microg mL(-1), with a detection limit of 0.6 ng mL(-1). The determination of carbaryl in garlic samples showed acceptable accuracy, which provided a new promising tool for analysis of enzyme inhibitors.
ESTHER : Du_2008_Analyst_133_1790
PubMedSearch : Du_2008_Analyst_133_1790
PubMedID: 19082085

Title : Electrochemical pesticide sensitivity test using acetylcholinesterase biosensor based on colloidal gold nanoparticle modified sol-gel interface - Du_2008_Talanta_74_766
Author(s) : Du D , Chen S , Cai J , Zhang A
Ref : Talanta , 74 :766 , 2008
Abstract : Based on the change in electrochemical behavior of enzymatic activity induced by pesticide, a novel electrochemical method for investigation of pesticide sensitivity using acetylcholinesterase (AChE) biosensor was developed. The sol-gel-derived silicate network assembling gold nanoparticles (AuNPs-SiSG) provided a biocompatible microenvironment around the enzyme molecule to stabilize its biological activity and prevented them from leaking out of the interface. The composite was characterized using atomic force microscopy and proved to be chemically clean, porous and homogeneous. AuNPs promoted a conductive pathway for electron transfer and improved electrochemical reactions at a lower potential. Typical pesticides such as monocrotophos, methyl parathion and carbaryl were selected for pesticide sensitivity tests. Due to the inhibitions of pesticides, the electrochemical responses of substrate on AChE-sensors decreased greatly. The inhibition curves showed good correspondence with the results by UV spectrophotometry assay. The proposed electrochemical pesticide sensitivity test exhibited high sensitivity, desirable accuracy, low cost and simplified procedures. This method could be developed as a conventional method to select efficient enzyme inhibitors and investigate toxic compounds against to enzyme.
ESTHER : Du_2008_Talanta_74_766
PubMedSearch : Du_2008_Talanta_74_766
PubMedID: 18371707

Title : In situ electrodeposited nanoparticles for facilitating electron transfer across self-assembled monolayers in biosensor design - Du_2008_Talanta_74_1337
Author(s) : Du D , Ding J , Cai J , Zhang J , Liu L
Ref : Talanta , 74 :1337 , 2008
Abstract : Gold nanoparticles (AuNPs) were synthesized in situ and electrodeposited onto Au substrate. The AuNPs modified interface facilitates electron transfer across self-assembled monolayers (SAMs) of 11-mercaptoundecanoic acid (MUA). After activation of surface carboxyl groups with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide, the interface displayed good stability for immobilization of biomolecules. These modification processes were characterized by contact angle measurement, cyclic voltammetry and electrochemical impedance spectra. The immobilized acetylcholinesterase (AChE), as a model, showed excellent activity to its substrate, leading to a stable AChE biosensor. Under the optimal experimental conditions, the inhibition of malathion on AChE biosensor was proportional to its concentration in two ranges, from 0.001 to 0.1 microg mL(-1) and from 0.1 to 25 microg mL(-1), with detection limit of 0.001 microg mL(-1). The simple method showed good reproducibility and acceptable stability, which had potential application in biosensor design.
ESTHER : Du_2008_Talanta_74_1337
PubMedSearch : Du_2008_Talanta_74_1337
PubMedID: 18371787

Title : An amperometric acetylthiocholine sensor based on immobilization of acetylcholinesterase on a multiwall carbon nanotube-cross-linked chitosan composite - Du_2007_Anal.Bioanal.Chem_387_1059
Author(s) : Du D , Huang X , Cai J , Zhang A , Ding J , Chen S
Ref : Anal Bioanal Chem , 387 :1059 , 2007
Abstract : A simple method has been devised for immobilization of acetylcholinesterase (AChE)--covalent bonding to a multiwall carbon nanotube (MWNT)--cross-linked chitosan composite (CMC)-and a sensitive amperometric sensor for rapid detection of acetylthiocholine (ATCl) has been based on this. Fourier-transform infrared spectroscopy proved that the native structure of the immobilized enzyme was preserved on this chemically clean and homogeneous composite film, because of the excellent biocompatibility and non-toxicity of chitosan. Glutaraldehyde was used as cross-linker to covalently bond the AChE, and efficiently prevented leakage of the enzyme from the film. Because of the inherent conductive properties of the MWNT, the immobilized AChE had greater affinity for ATCl and excellent catalytic effect in the hydrolysis of ATCl, with a K(app)(m) value of 132 micromol L(-1), forming thiocholine, which was then oxidized to produce a detectable and rapid response. Under optimum conditions the amperometric current increased linearly with the increasing concentration of ATCl in the range 2.0-400 micromol L(-1), with a detection limit of 0.10 micromol L(-1). Fabrication reproducibility of the sensor was good and the stability was acceptable. The sensor is a promising new tool for characterization of enzyme inhibitors and for pesticide analysis. Abstract.
ESTHER : Du_2007_Anal.Bioanal.Chem_387_1059
PubMedSearch : Du_2007_Anal.Bioanal.Chem_387_1059
PubMedID: 17186224

Title : Comparison of pesticide sensitivity by electrochemical test based on acetylcholinesterase biosensor - Du_2007_Biosens.Bioelectron_23_285
Author(s) : Du D , Huang X , Cai J , Zhang A
Ref : Biosensors & Bioelectronics , 23 :285 , 2007
Abstract : Based on the change in electrochemical behavior of enzymatic activity induced by pesticide, a novel electrochemical method has been devised for investigation of pesticide sensitivity using acetylcholinesterase (AChE) biosensor. Because of the excellent biocompatibility and good stability of chitosan matrix, it prevented leakage of the AChE from electrode. Multiwall carbon nanotube (MWNT) promoted electron transfer reaction at a lower potential and catalyzed the electro-oxidation of thiocholine, thus amplifying the sensitivity and amperometric response of the biosensor. Four pesticides of carbaryl, malathion, dimethoate and monocrotophos were selected to discuss their inhibition efficiencies to AChE. The inhibition curves were similar to Michealis-Menten and the Michealis-Menten constants (Km) were calculated to be 0.96 microM, 1.78 microM, 1.97 microM and 4.28 microM, respectively. Ninety-five percent reactivation of the inhibited AChE could be regenerated using pralidoxime iodide within 8 min. The proposed electrochemical pesticide sensitivity test exhibited high sensitivity, low cost and simplified procedures, which is a promising new tool for comparison of pesticide sensitivity and for selection of the most efficient enzyme inhibitors.
ESTHER : Du_2007_Biosens.Bioelectron_23_285
PubMedSearch : Du_2007_Biosens.Bioelectron_23_285
PubMedID: 17590326

Title : Immobilization of acetylcholinesterase on gold nanoparticles embedded in sol-gel film for amperometric detection of organophosphorous insecticide - Du_2007_Biosens.Bioelectron_23_130
Author(s) : Du D , Chen S , Cai J , Zhang A
Ref : Biosensors & Bioelectronics , 23 :130 , 2007
Abstract : A simple method to immobilize acetylcholinesterase (AChE) on silica sol-gel (SiSG) film assembling gold nanoparticles (AuNPs) was proposed, thus a sensitive, fast and stable amperometric sensor for quantitative determination of organophosphorous insecticide was developed. The large quantities of hydroxyl groups in the sol-gel composite provided a biocompatible microenvironment around enzyme molecule and stabilized its biological activity to a large extent. The immobilized AChE could catalyze the hydrolysis of acetylthiocholine chloride (ATCl) with a Kmapp value of 450 microM to form thiocholine, which was then oxidized to produce detectable single with a linear range of 10-1000 microM. AuNPs catalyzed the electro-oxidation of thiocholine, thus increasing detection sensitivity. Based on the inhibition of organophosphorous insecticide on the enzymatic activity of AChE, using monocrotophos as a model compound, the conditions for detection of the insecticide were optimized. The inhibition of monocrotophos was proportional to its concentration ranging from 0.001 to 1 microg/ml and 2 to 15 microg/ml, with the correlation coefficients of 0.9930 and 0.9985, respectively. The detection limit was 0.6 ng/ml at a 10% inhibition. The developed biosensor exhibited good reproducibility and acceptable stability, thus providing a new promising tool for analysis of enzyme inhibitors.
ESTHER : Du_2007_Biosens.Bioelectron_23_130
PubMedSearch : Du_2007_Biosens.Bioelectron_23_130
PubMedID: 17499494

Title : Determination of carbaryl pesticide using amperometric acetylcholinesterase sensor formed by electrochemically deposited chitosan - Du_2007_Colloids.Surf.B.Biointerfaces_58_145
Author(s) : Du D , Ding J , Cai J , Zhang A
Ref : Colloids Surf B Biointerfaces , 58 :145 , 2007
Abstract : A sensitive, fast and cheap sensor for quantitative determination of carbaryl pesticide using amperometric acetylcholinesterase (AChE) sensor based on electrochemically deposited chitosan was reported. From a mildly acidic chitosan solution, a chitosan film is electrochemically deposited on Au electrode surface via a negative voltage bias, leading to a stable AChE sensor. The characteristics of the deposited layer were observed to be dependent upon the deposition time, pH, and the chitosan concentration. Fourier-transform infrared spectra proved that the immobilized enzyme could preserve their native structure due to the excellent biocompatibility and non-toxicity of chitosan. Under the optimal experimental conditions, the carbaryl inhibition on AChE-CHIT/Au was proportional to its concentration in two ranges, from 0.005 to 0.1 microg/ml and 0.5 to 5 microg/ml, with the correlation coefficients of 0.9966 and 0.9982, respectively. The detection limit was 0.003 microg/ml taken as the concentration equivalent to a 10% decrease in signal. The determination of carbaryl in garlic samples obtained from export of farm base showed acceptable accuracy. The developed sensor exhibited good fabrication reproducibility and acceptable stability, which provided a new promising tool for pesticide analysis.
ESTHER : Du_2007_Colloids.Surf.B.Biointerfaces_58_145
PubMedSearch : Du_2007_Colloids.Surf.B.Biointerfaces_58_145
PubMedID: 17434296

Title : Molecularly imprinted polymer for monocrotophos and its binding characteristics for organophosphorus pesticides - Zhu_2005_Ann.Chim_95_877
Author(s) : Zhu X , Yang J , Su Q , Cai J , Gao Y
Ref : Ann Chim , 95 :877 , 2005
Abstract : In this study, molecular imprinting was used to develop a method based on noncovalent interaction for the synthesis of a monocrotophos-specific polymer. The selective binding characteristics of the template polymer were evaluated by 1H NMR study. The result was consistent with the existence of multi-molecular complexes formed by hydrogen-bonding interactions. Batch rebinding studies in acetonitrile were undertaken to quantitatively evaluate the affinity of the polymer for monocrotophos. The experimental binding isotherms were fitted to the Freundlich isotherm and the total number of binding sites of the polymer can be calculated to be 4.046 micromol g(-1). The induced affinity and selectivity by imprinting were examined chromatographically. The polymer gave more than 15 times longer retention for monocrotophos than the nonimprinted polymer with the same chemical composition. Other organophosphorus pesticides under study were eluted close to the void volume on the polymer column.
ESTHER : Zhu_2005_Ann.Chim_95_877
PubMedSearch : Zhu_2005_Ann.Chim_95_877
PubMedID: 16398351

Title : Protective effect of tetramethylpyrazine on learning and memory function in D-galactose-lesioned mice - Zhang_2004_Chin.Med.Sci.J_19_180
Author(s) : Zhang C , Wang SZ , Zuo PP , Cui X , Cai J
Ref : Chin Med Sci J , 19 :180 , 2004
Abstract : OBJECTIVE: To explore the protective effect of tetramethylpyrazine (TMP) on the learning and memory function in D-galactose (D-gal)-lesioned mice.
METHODS: C57BL/6 mice were injected (s.c.) 2% D-gal for 40 days (100 mg x kg(-1) x d(-1)). Normal saline, TMP, and Huperzine A were respectively given by intragastric administration in different groups from the third week. Learning and memory ability was tested with Morris water maze for 5 days at the sixth week. After completion of behavioral test, the mice were sacrificed by decapitation. The brain was rapidly removed, and the cortex and hippocampus were separated. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in the cortex were determined. At the same time, the activity of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE), the binding sites (Bmax) and the affinity (KD) of M-cholinergic receptor in the cortex, and Bmax and KD of N-methyl-D-aspartate (NMDA) receptor in the hippocampus were determined.
RESULTS: In this model group, (1) The deficit of learning and memory ability, (2) elevated MDA content and lowered SOD activity, (3) decreased AChE activity and M-cholinergic receptor binding sites in the cortex, and (4) lowered NMDA receptor binding sites were observed in the hippocampus, as compared with the normal control. TMP could markedly (1) attenuate cognitive dysfunction, (2) lower MDA content and elevate SOD activity, (3) increase the activity of ChAT and AChE, and M-cholinergic receptor binding sites in the cortex in the mice treated with D-gal. NMDA receptor binding sites were also increased in the hippocampus in the treated mice. CONCLUSION: TMP can significantly strengthen antioxidative function, improve central cholinergic system function, protect NMDA receptor activity, and thus enhance the learning and memory ability in D-gal-lesioned mice.
ESTHER : Zhang_2004_Chin.Med.Sci.J_19_180
PubMedSearch : Zhang_2004_Chin.Med.Sci.J_19_180
PubMedID: 15506643

Title : [Effect of tetramethylpyrazine on learning, memory and cholinergic system in D-galactose-lesioned mice] - Zhang_2003_Zhongguo.Yi.Xue.Ke.Xue.Yuan.Xue.Bao_25_553
Author(s) : Zhang C , Wang SZ , Zuo PP , Cui X , Cai J
Ref : Zhongguo Yi Xue Ke Xue Yuan Xue Bao , 25 :553 , 2003
Abstract : OBJECTIVE: To explore the effect of tetramethylpyrazine on learning, memory, and cholinergic system in D-galactose-lesioned mice.
METHODS: C57BL/6J mice were given subcutaneous injection of 2% D-galactose for 40 days (100 mg.kg-1.d-1). Normal saline, tetramethylpyrazine (TMP) and Huperzine A (HupA) were given respectively by intragastric administration in different study groups from the third week on. Learning and memory ability were tested by Morris water maze for 5 days at the sixth week. Acetylcholinesterase (AchE) activity, the binding sites (Bmax) and the affinity (KD) of M-cholinergic receptor were determined.
RESULTS: The learning and memory dysfunction, with lowered AchE activity and M-cholinergic receptor binding sites were found in the model group as compared with the normal control group. The tetramethylpyrazine, especially at the dose of 100 mg.kg-1.d-1, could markedly attenuate cognitive dysfunction, while elevate the lowered AchE activity (P < 0.05) and M-cholinergic receptor binding sites (P < 0.005) in the cerebral cortex of mice treated with D-galactose.
CONCLUSIONS: The tetramethylpyrazine can significantly improve central cholinergic system function, and thus enhance the learning and memory ability in D-galactose-lesioned mice.
ESTHER : Zhang_2003_Zhongguo.Yi.Xue.Ke.Xue.Yuan.Xue.Bao_25_553
PubMedSearch : Zhang_2003_Zhongguo.Yi.Xue.Ke.Xue.Yuan.Xue.Bao_25_553
PubMedID: 14650157

Title : C3,4 transfer for neurotization of C5,6 nerve roots in brachial plexus injury in a rabbit model - Cao_2003_J.Reconstr.Microsurg_19_265
Author(s) : Cao X , Li J , Cao Y , Cai J
Ref : J Reconstr Microsurg , 19 :265 , 2003
Abstract : To evaluate the root neurotization properties of extraplexal donor nerves, an avulsion injury model of brachial plexus was created and repaired by C 3,4 nerve-root transfers in the rabbit. Eighteen rabbits were divided into three groups. In Group 1 (n = 6), the right C 5,6 nerve roots were avulsed and bridged by a nerve graft taken from the femoral nerve, with C 3,4 as C 3 to C 5 and C 4 to C 6. In Group 2 (n = 6), the right C 5,6 nerve roots were cut and directly sutured end-to-end. Group 3 (n = 6) was a negative group, in which C 5,6 nerve roots were avulsed without repair. All three groups were positively controlled by the contralateral side. Postoperative behavior observation and anatomic, electrophysiologic studies were conducted 4 months later for comparison among groups. Axon existence was observed by acetylcholinesterase staining. Results showed that active motion was not found in all three groups by the end of the study. Extraplexal nerve transfer indeed was able to re-neurotize the avulsed nerve roots down to their target organ, but C 3,4 nerve transfer was weaker than direct end-to-end suture, in terms of neurotization ability. The authors conclude that "root or trunk repair" for avulsion injury of the brachial plexus is possible, provided that the donor nerve has enough fibers and the nerve regeneration ability is increased by modern moleculobiologic techniques.
ESTHER : Cao_2003_J.Reconstr.Microsurg_19_265
PubMedSearch : Cao_2003_J.Reconstr.Microsurg_19_265
PubMedID: 12858250