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micropatterned multienzyme devices with adjustable amounts of immobilized enzymes.multienzyme microstructures of glucose oxidase (gox) and horseradish peroxidase (hrp) were prepared by layer-by-layer deposition inside microfluidic networks on glass substrates in order to allow both site-specific deposition and control of the amount of immobilized enzymes. the obtained microstructures were characterized by scanning force microscopy for the topography of the deposited layers. the local enzyme activity was characterized by the substrate-generation/tip-collection mode and the enz ...201324200032
an organic thin film photodiode as a portable photodetector for the detection of alkylphenol polyethoxylates by a flow fluorescence-immunoassay on magnetic microbeads in a microchannel.an organic thin film photodiode (opd) was successfully employed as a portable photodetector in a competitive enzyme-linked immunosorbent assay (elisa) of a class of nonionic surfactants, namely alkylphenol polyethoxylates (apneos) which are an environmental pollutant. microbeads that were chemically immobilized with an anti-apneos antibody were used in the assay. the opd consisted of a layer of copper phthalocyanine (cupc), c60 and a second layer of bathocuproine (bcp) with a bulk heterojunction ...201324209322
design, synthesis and evaluation of a cellular stable and detectable biotinylated fumagillin probe and investigation of cell permeability of fumagillin and its analogs to endothelial and cancer cells.fumagillin (1), a natural product of fungal origin, and its analogs were discovered to be extremely potent and highly selective inhibitors restraining endothelial cell proliferation in vitro by covalently binding to metap2. in order to further understand the unclear biological mechanisms and pharmacological processes of fumagillin and its derivatives, fumagillin-biotin conjugate 8 was designed and synthesized, which is linked with a 27-atom connection chain and by urethane (carbamate) bonds betw ...201324211639
selective vulnerability of hippocampal sub-fields to oxygen-glucose deprivation is a function of animal age.for more than a century, the hippocampal sub-fields have been recognized as being differentially vulnerable to injury. while the cause remains unknown, the explanations generally considered have involved either vascular differences, or innate variability among cells. to examine the latter possibility, we prepared acute hippocampal slices from sprague-dawley rats, applied a brief period of oxygen-glucose deprivation (ogd; an in vitro model of ischemia), and assessed the viability of dissected sub ...201424211659
microrna-101 inhibits human hepatocellular carcinoma progression through ezh2 downregulation and increased cytostatic drug sensitivity.oncogene polycomb group protein enhancer of zeste homolog 2 (ezh2) has been proposed to be a target gene of putative tumor suppressor microrna-101 (mir-101). the aim of our study was to investigate the functional role of both mir-101 and ezh2 in human hepatocellular carcinoma (hcc).201424211739
measurement of salivary cortisol by a chemiluminescent organic-based immunosensor.a highly sensitive chemiluminescent immunoassay (clia) using a sensitive organic photodetector was developed to detect human cortisol, an important biomarker for stress-related diseases. the developed clia was performed onto gold-coated glass chips, on which anti-cortisol antibodies were immobilised and chemiluminescent horseradish peroxidase-luminol-peroxide reactions were generated. using cortisol-spiked artificial saliva samples, the clia biosensor showed a linear range of detection between 0 ...201424211877
direct electron transfer of horseradish peroxidase on a functional nanocomplex modified glassy carbon electrode.direct electron transfer of horseradish peroxidase (hrp) was achieved by immobilizing hrp on a functional nanocomplex modified glassy carbon (gc) electrode. the cyclic voltammograms (cvs) of the modified electrode have a pair of well-defined redox peaks with a formal potential (e°') of -26 ± 2 mv versus ag/agcl, in 0.05 m, ph7.0 phosphate buffer solution (pbs) at a scan rate of 0.05 v/s. the heterogeneous electron transfer constant (ks) was calculated to be 1.94 s-1. the modified electrode respo ...201424211999
differential cortical neurotrophin and cytogenetic adaptation after voluntary exercise in normal and amnestic rats.voluntary exercise (vex) has profound effects on neural and behavioral plasticity, including recovery of cns trauma and disease. however, the unique regional cortical adaption to vex has not been elucidated. in a series of experiments, we first examined whether vex would restore and retain neurotrophin levels in several cortical regions (frontal cortex [fc], retrosplenial cortex [rsc], occipital cortex [oc]) in an animal model (pyrithiamine-induced thiamine deficiency [ptd]) of the amnestic diso ...201424215977
expression of β1- and β2-adrenoceptors in different subtypes of interneurons in the medial prefrontal cortex of mice.noradrenaline acting via β-adrenoceptors (β-ars) in the cns plays an important role in learning/memory and cognitive functions. β-ars have been shown to be expressed in cortical pyramidal and subcortical principal cells. however, little is known about β-ar expression in different subtypes of gabaergic neurons. here, we report that both β1- and β2-ars are expressed in a majority of gabaergic interneurons in the medial prefrontal cortex of mice, including parvalbumin (pv)-, calretinin (cr)-, calbi ...201424215978
gaba-induced uncoupling of gaba/benzodiazepine site interactions is mediated by increased gabaa receptor internalization and associated with a change in subunit composition.persistent activation of gabaa receptors triggers compensatory changes in receptor function that are relevant to physiological, pathological and pharmacological conditions. chronic treatment of cultured neurons with gaba for 48h has been shown to produce a down-regulation of receptor number and an uncoupling of gaba/benzodiazepine site interactions with a half-time of 24-25h. down-regulation is the result of a transcriptional repression of gabaa receptor subunit genes and depends on activation o ...201424215979
differential up-regulation of vesl-1/homer 1 protein isoforms associated with decline in visual performance in a preclinical glaucoma model.glaucoma is a multifactorial progressive ocular pathology, clinically presenting with damage to the retina and optic nerve, ultimately leading to blindness. retinal ganglion cell loss in glaucoma ultimately results in vision loss. vesl/homer proteins are scaffolding proteins that are critical for maintaining synaptic integrity by clustering, organizing and functionally regulating synaptic proteins. current anti-glaucoma therapies target iop as the sole modifiable clinical parameters. long-term p ...201424219919
novel tacrine-ebselen hybrids with improved cholinesterase inhibitory, hydrogen peroxide and peroxynitrite scavenging activity.a series of tacrine-ebselen hybrids were synthesised and evaluated as possible multifunctional anti-alzheimer's disease (ad) agents. compound 6i, which is tacrine linked with 5,6-dimethoxybenzo[d][1,2]selenazol-3(2h)-one by a six-carbon spacer, was the most potent acetylcholinesterase (ache) and butylcholinesterase (buche) inhibitor, with ic50 values of 2.55 and 2.80 nm, respectively. furthermore, this compound demonstrated similar hydrogen peroxide and peroxynitrite scavenging activity as ebsel ...201324220172
antioxidant action of 7,8-dihydroxyflavone protects pc12 cells against 6-hydroxydopamine-induced cytotoxicity.oxidative stress-induced neuronal death plays a pivotal role in pathogenesis of neurodegenerative disorders. recently, 7,8-dihydroxyflavone (7,8-dhf) has been shown to exert neuroprotective effects by acting as a selective tyrosine kinase receptor b (trkb) agonist. in addition, the antioxidant action of 7,8-dhf may protect neuronal cells against oxidative injury. in the present study, we used pc12 cells, a cell line generally thought to lack trkb, to investigate the effect of 7,8-dhf on 6-hydrox ...201424220540
antigenic relationships between petunia peroxidase a and specific peroxidase isoenzymes in other solanaceae.a highly specific rabbit antiserum raised against peroxidase (prxa) from petunia (petunia hybrida) was used to investigate the antigenic relatedness of peroxidases in the solanaceae. after sds-page of crude leaf extracts from a large number of species of this family, immunoblotting revealed that cross-reacting protein bands were present in all species tested. in order to determine whether these protein bands represent peroxidases, the peroxidase isoenzymes in thorn apple (datura stramonium l.), ...199024220819
identification of a monoclonal antibody to abscission tissue that recognises xylose/fucose-containing n-linked oligosaccharides from higher plants.monoclonal antibodies raised against extracts of the rachis abscission zone of sambucus nigra l. were selected for high reactivity towards abscission-zone proteins. one antibody (yz1/2.23) has been shown to cross-react, by both indirect and competition enzyme-linked immunosorbent assay and by western blotting, with a number of plant enzymes including horseradish peroxidase, rice α-glucosidase, almond β-glucosidase and the lectins from phaseolus vulgaris and erythrina cristagalli.the major n-link ...198824221933
recycling of the high valence states of heme proteins by cysteine residues of thimet-oligopeptidase.the peptidolytic enzyme thimet-oligopeptidase (top) is able to act as a reducing agent in the peroxidase cycle of myoglobin (mb) and horseradish peroxidase (hrp). the top-promoted recycling of the high valence states of the peroxidases to the respective resting form was accompanied by a significant decrease in the thiol content of the peptidolytic enzyme. epr (electron paramagnetic resonance) analysis using dbnbs spin trapping revealed that top also prevented the formation of tryptophanyl radica ...201324223886
diets high in fermentable protein and fibre alter tight junction protein composition with minor effects on barrier function in piglet colon.protein fermentation end products may damage the colonic mucosa, which could be counteracted by dietary inclusion of fermentable carbohydrates (fcho). although fermentable crude protein (fcp) and fcho are known to affect microbial ecology, their interactive effects on epithelial barrier function are unknown. in the present study, in a 2 × 2 factorial experiment, thirty-two weaned piglets were fed low-fcp/low-fcho (14·5 % crude protein (cp)/14·5 % total dietary fibre (tdf)), low-fcp/high-fcho (14 ...201424229735
4-methylthio-butanyl derivatives from the seeds of raphanus sativus and their biological evaluation on anti-inflammatory and antitumor activities.raphanus sativus seeds (brassicaceae) known as raphani semen have long been used as anti-cancer and/or anti-inflammatory agents in korean traditional medicine. this study was designed to isolate the bioactive constituents from the seed extracts of raphanus sativus and evaluate their anti-inflammatory and antitumor activities.201424231071
effect of architecture on the activity of glucose oxidase/horseradish peroxidase/carbon nanoparticle conjugates.we investigate the activity of glucose oxidase (gox) together with horseradish peroxidase (hrp) on carbon nanoparticles (cnps). because gox activity relies on hrp, we probe how the arrangement of the enzymes on the cnps affects enzymatic behavior. colorimetric assays to probe activity found that the coupling strategy affects activity of the bienzyme-nanoparticle complex. gox is more prone than hrp to denaturation on the cnp surface, where its activity is compromised, while hrp activity is enhanc ...201424231087
delayed luminescence of luminol initiated by a membrane-bound peroxidase.the luminescense of the luminol-h2o2 system was initiated by either free or membrane-bound horseradish peroxideae (hrp). the instantaneous luminescene decayed rapidly and was followed by the delayed luminescence in the presence of excess luminol. the delayed luminescence was characterized by a chain reaction, in which luminescence intensity increased exponentially. membrane-bound hrp demonstrated that the delayed luminescence took place even in the absence of hrp if the instantaneous luminescenc ...198124233883
immunocapillarymigration : use of fluorescein- and enzyme-labeled antibodies to quantify c-reactive protein.the method is based upon the attachment of antibodies to a porous insoluble support and the subsequent capillary migration of the antigen-containing solution in the support. the antigen-covered area thereby obtained was visualized with fluoresceinor horseradish peroxidase-labeled antibodies. the height of this area increased with increasing antigen concentration. the method was used to quantitate c-reactive protein.198224234092
nonenzymatic glycosylation of human serum albumin: fluorescence and chemiluminescence behavior.in the present study the progress of the cross-linking reaction between glyceraldehyde (gca) and human serum albumin (hsa) was followed by monitoring the development of new absorption bands characteristic of the cross-linked product. generation of electronically excited species (ees) during horseradish peroxidase (hrp)-catalyzed oxidation of glycosylated hsa was followed by measuring direct chemiluminescence. it was found that adducts of hsa with gca in the presence of hrp are capable of forming ...199324234897
erythroid differentiation is augmented in reelin-deficient k562 cells and homozygous reeler mice.reelin is an extracellular glycoprotein that is highly conserved in mammals. in addition to its expression in the nervous system, reelin is present in erythroid cells but its function there is unknown. we report in this study that reelin is up-regulated during erythroid differentiation of human erythroleukemic k562 cells and is expressed in the erythroid progenitors of murine bone marrow. reelin deficiency promotes erythroid differentiation of k562 cells and augments erythroid production in muri ...201424239537
resveratrol contributes to chemosensitivity of malignant mesothelioma cells with activation of p53.resveratrol is a naturally occurring polyphenolic phytoalexin with chemopreventive properties. we previously reported a synergistic anti-proliferative effect of resveratrol and clofarabine against malignant mesothelioma (mm) cells. here, we further investigated molecular mechanisms involved in the synergistic interaction of these compounds in mm msto-211h cells. resveratrol, in combination with clofarabine, time-dependently induced a strong cytotoxic effect with the nuclear accumulation of phosp ...201424239893
optimized selection of anti-tumor recombinant antibodies from phage libraries on intact cells.generation of human recombinant antibody libraries displayed on the surface of the filamentous phage and selection of specific antibodies against desirable targets allows production of fully human antibodies usable for repeated administration in humans. various lymphoid tissues from immunized donors, such as lymph nodes or peripheral blood lymphocytes from individuals with tumor or lymphocytes infiltrating tumor masses may serve as a source of specific anti-tumor antibody repertoire for generati ...201424240062
nitric oxide drives embryonic myogenesis in chicken through the upregulation of myogenic differentiation factors.the muscle-specific variant of neuronal nitric oxide (no) synthase (nos-i), is developmentally regulated in mouse suggesting a role of no during myogenesis. in chick embryo, a good model of development, we found that the expression of nos-i is up-regulated, but only in the early phase of development. through a pharmacological intervention in ovo we found that no signalling plays a relevant role during embryonic development. the inhibition of nos-i decreased the growth of embryo, in particular of ...201424240125
one-electron oxidation of diclofenac by human cytochrome p450s as a potential bioactivation mechanism for formation of 2'-(glutathion-s-yl)-deschloro-diclofenac.reactive metabolites have been suggested to play a role in the idiosyncratic hepatotoxicity observed with diclofenac (df). by structural identification of the gsh conjugates formed after p450-catalyzed bioactivation of df, it was shown that three types of reactive intermediates were formed: p-benzoquinone imines, o-imine methide and arene-oxide. recently, detection of 2'-(glutathion-s-yl)-deschloro-diclofenac (ddf-sg), resulting from chlorine substitution, suggested the existence of a fourth typ ...201424246759
regeneration of horseradish hairy roots incited by agrobacterium rhizogenes infection.surface-sterilized leaf disks of horse-radish (armoracia lapathifolia) were immersed in a suspension of agrobacterium rhizogenes harboring the root-inducing plasmid (pri) and cultured on a solid medium. within about 10 days after inoculation, adventitious roots (hairy roots) emerged from the leaf disks. no roots emerged from the uninoculated leaf disks. the excised hairy roots grew vigorously in the dark and exhibited extensive lateral branches in the absence of phytohormones. when the hairy roo ...198724248760
immunohistochemical expression of basement membrane laminin in histological grades of oral squamous cell carcinoma: a semiquantitative analysis.to determine the immunohistochemical (ihc) localization of basement membrane component laminin in histological grades of oral squamous cell carcinoma (oscc). the purpose of this study was to demonstrate the loss of continuity of the basement membrane in oscc using an antibody directed against laminin using advanced polymer staining system.201324250076
tyrosine residues play an important role in heme detoxification by serum albumin.serum albumin binds avidly to heme to form heme-serum albumin complex, also called methemalbumin, and this binding is thought to protect against the potentially toxic effects of heme. however, the mechanism of detoxification has not been fully elucidated.201424252277
detection of venom-antivenom (vav) immunocomplexes in vitro as a measure of antivenom efficacy.the measurement of free venom with enzyme immunoassay in serum of patients with snake envenoming is used to confirm snake identification and to determine if sufficient antivenom has been given. recent studies with russell's viper (rv; daboia russelii) envenoming have detected free venom post-antivenom despite recovery of coagulopathy. this raises the question as to whether this assay also measures venom-antivenom (vav) complexes. in this study we developed an assay to measure vav complexes and i ...201424252422
a simple and sensitive immunoassay for the determination of human chorionic gonadotropin by graphene-based chemiluminescence resonance energy transfer.in this study, we report a strategy of chemiluminescence resonance energy transfer (cret) using graphene as an efficient long-range energy acceptor. magnetic nanoparticles were also used in cret for simple magnetic separation and immobilization of horseradish peroxidase (hrp)-labeled anti-hcg antibody. in the design of cret system, the sandwich-type immunocomplex was formed between human chorionic gonadotropin (hcg, antigen) and two different antibodies bridged the magnetic nanoparticles and gra ...201424252762
knockout of an endogenous mannosyltransferase increases the homogeneity of glycoproteins produced in pichia pastoris.the yeast pichia pastoris is a common host for the recombinant production of biopharmaceuticals, capable of performing posttranslational modifications like glycosylation of secreted proteins. however, the activity of the och1 encoded α-1,6-mannosyltransferase triggers hypermannosylation of secreted proteins at great heterogeneity, considerably hampering downstream processing and reproducibility. horseradish peroxidases are versatile enzymes with applications in diagnostics, bioremediation and ca ...201324252857
functionality of dielectrophoretically immobilized enzyme molecules.the enzyme horseradish peroxidase has been immobilized on nanoelectrode arrays by alternating current dielectrophoresis (dep). preservation of its enzymatic function after field application was demonstrated by oxidizing dihydrorhodamine 123 with hydrogen peroxide as co-oxidant to create its fluorescent form, rhodamine 123 (rh123). localization of the fluorescently labeled enzyme and its product was conducted by fluorescence microscopy. nanoelectrodes were prepared as tungsten pins arranged in sq ...201424254805
ternary composite of hemin, gold nanoparticles and graphene for highly efficient decomposition of hydrogen peroxide.a ternary composite of hemin, gold nanoparticles and graphene is prepared by a two-step process. firstly, graphene-hemin composite is synthesized through π-π interaction and then hydrogen tetracholoroauric acid is reduced in situ by ascorbic acid. this ternary composite shows a higher catalytic activity for decomposition of hydrogen peroxide than that of three components alone or the mixture of three components. the michaelis constant of this composite is 5.82 times lower and the maximal reactio ...201324257652
identification, expression and bioactivity of hexokinase in amphioxus: insights into evolution of vertebrate hexokinase genes.hexokinase family includes hexokinases i, ii, iii and iv, that catalyze the phosphorylation of glucose to produce glucose 6-phosphate. hexokinase iv, also known as glucokinase, is only half size of the other types of hexokinases that contain two hexokinase domains. despite the enormous progress in the study of hexokinases, the evolutionary relationship between glucokinase and other hexokinases is still uncertain, and the molecular processes leading to the emergence of hexokinases in vertebrates ...201424262936
enzyme-capped relay-functionalized mesoporous carbon nanoparticles: effective bioelectrocatalytic matrices for sensing and biofuel cell applications.the porous high surface area and conducting properties of mesoporous carbon nanoparticles, cnps (<500 nm diameter of nps, pore dimensions ∼6.3 nm), are implemented to design electrically contacted enzyme electrodes for biosensing and biofuel cell applications. the relay units ferrocene methanol, fc-meoh, methylene blue, mb(+), and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), abts(2-), are loaded in the pores of the mesoporous cnps, and the pores are capped with glucose oxidase, gox, ho ...201324266869
a two-stage enzymatic synthesis of conductive poly(3,4-ethylenedioxythiophene).the conductive polymer, poly(3,4-ethylenedioxythiophene) (pedot), possesses attractive properties that show the potential applications in many fields. in this study, we have proposed a two-stage enzymatic synthesis of conductive pedot. horseradish peroxidase (hrp) acts as the catalyst to promote the generation of edot free radicals followed by the polymerization under the room temperature in the presence of poly(sodium 4-styrenesulfonate) (pss), then a mild heating process is employed for furthe ...201424267567
the reactivation of nitrate reductase from spinach (spinacea oleracea l.) inactivated by nadh and cyanide: effects of peroxidase and associated systems.nitrate reductase of spinach (spinacea oleracea l.) leaves which had been inactivated in vitro by treatment with nadh and cyanide, was reactivated by incubation with oxidant systems and measured as fmnh2-dependent activity. ferricyanide, a purely chemical oxidant, produced rapid maximal reactivation (100%) which was 90% complete in less than 3 min. reactivation occurred slowly and less completely (30-75% in 30 or 60 min) when the enzyme was incubated with pure horseradish peroxidase alone, depen ...198224272572
fully automated analytical procedure for propofol determination by sequential injection technique with spectrophotometric and fluorimetric detections.in this work, an application of an enzymatic reaction for the determination of the highly hydrophobic drug propofol in emulsion dosage form is presented. emulsions represent a complex and therefore challenging matrix for analysis. ethanol was used for breakage of a lipid emulsion, which enabled optical detection. a fully automated method based on sequential injection analysis was developed, allowing propofol determination without the requirement of tedious sample pre-treatment. the method was ba ...201424274276
tuning the activities and structures of enzymes bound to graphene oxide with a protein glue.graphene oxide (go) is being investigated extensively for enzyme and protein binding, but many enzymes bound to go denature considerably and lose most of their activities. a simple, novel, and efficient approach is described here for improving the structures and activities of enzymes bound to go such that bound enzymes are nearly as active as those of the corresponding unbound enzymes. our strategy is to preadsorb highly cationized bovine serum albumin (cbsa) to passivate go, and cbsa/go (bgo) s ...201324274382
peroxidase-encapsulated cyclodextrin nanosponge immunoconjugates as a signal enhancement tool in optical and electrochemical assays.cyclodextrin nanosponges bearing carboxylate groups have been prepared by crosslinking β-cyclodextrin with pyromellitic dianhydride to form a carboxylic acid terminated nanoporous material. the surface of the particles was covalently modified with an anti-igg antibody and then loaded with horseradish peroxidase. the structures of unmodified and protein modified nanosponge particles were investigated by raman spectroscopy and imaging methods. confocal microscopy indicates that the antibody is loc ...201424276364
mechanisms for covalent immobilization of horseradish peroxidase on ion-beam-treated polyethylene.the surface of polyethylene was modified by plasma immersion ion implantation. structure changes including carbonization and oxidation were observed. high surface energy of the modified polyethylene was attributed to the presence of free radicals on the surface. the surface energy decay with storage time after treatment was explained by a decay of the free radical concentration while the concentration of oxygen-containing groups increased with storage time. horseradish peroxidase was covalently ...201224278665
a cost-effective sandwich electrochemiluminescence immunosensor for ultrasensitive detection of hiv-1 antibody using magnetic molecularly imprinted polymers as capture probes.in this report, a rapid and cost-effective sandwich electrochemiluminescence (ecl) immunosensor was constructed for the ultrasensitive detection of human immunodeficiency virus type 1 antibody (anti-hiv-1) using magnetic molecularly imprinted polymers (mmips) as capture probes by combining surface and epitope imprinting techniques and antigen conjugated with horseradish peroxidase (hrp-hiv-1) as labels. first, 3-aminobenzeneboronic acid (apba) was used as the functional monomer and cross-linking ...201424280050
activation of paraoxonase 1 is associated with hdl remodeling ex vivo.we hypothesize that during high density lipoprotein (hdl) remodeling pon1 reaches an optimal distribution in hdl subclasses by which it achieves maximum activity. we conducted this study to gain insight on pon1 fate and activation during short-term hdl remodeling ex vivo.201424280342
aptamer biosensor for sensitive detection of toxin a of clostridium difficile using gold nanoparticles synthesized by bacillus stearothermophilus.a sensitive electrochemical biosensor was developed to detect toxin a (toa) of clostridium difficile based on an aptamer selected by the systematic evolution of ligands using exponential enrichment and gold nanoparticles (gnps) synthesized by bacillus stearothermophilus. the thiolated single-stranded dna used as the capture probe (cp) was first self-assembled on a nafion-thionine-gnps-modified screen-printed electrode (spe) through an au-thiol interaction. the horseradish peroxidase (hrp)-labele ...201424287407
jellyfish collagen stimulates production of tnf-α and il-6 by j774.1 cells through activation of nf-κb and jnk via tlr4 signaling pathway.we previously reported that jellyfish collagen stimulates both the acquired and innate immune responses. in the acquired immune response, jellyfish collagen enhanced immunoglobulin production by lymphocytes in vitro and in vivo. meanwhile, in the innate immune response jellyfish collagen promoted cytokine production and phagocytotic activity of macrophages. the facts that jellyfish collagen plays several potential roles in stimulating cytokine production by macrophages have further attracted us ...201424291243
effects of c-glycosylation on anti-diabetic, anti-alzheimer's disease and anti-inflammatory potential of apigenin.apigenin has gained particular interests in recent years as a beneficial and health promoting agent because of its low intrinsic toxicity. vitexin and isovitexin, naturally occurring c-glycosylated derivatives of apigenin, have been known to possess potent anti-diabetic, anti-alzheimer's disease (anti-ad), and anti-inflammatory activities. the present study was designed to investigate the anti-diabetic, anti-ad, and anti-inflammatory potential of apigenin and its two c-glycosylated derivatives, ...201424291393
layer-by-layer multienzyme assembly for highly sensitive electrochemical immunoassay based on tyramine signal amplification strategy.a new sandwich-type electrochemical immunosensor based on nanosilver-doped bovine serum albumin microspheres (ag@bsa) with a high ratio of horseradish peroxidase (hrp) and detection antibody was developed for quantitative monitoring of biomarkers (carcinoembryonic antigen, cea, used in this case) by coupling enzymatic biocatalytic precipitation with tyramine signal amplification strategy on capture antibody-modified glassy carbon electrode. two immunosensing protocols (with and without tyramine ...201424291751
quantum dots sensitized titanium dioxide decorated reduced graphene oxide for visible light excited photoelectrochemical biosensing at a low potential.a low potential and competitive photoelectrochemical biosensing platform was developed using quantum dots sensitized titanium dioxide decorated reduced graphene oxide (tio2-rgo) nanocomposites. the nanocomposites were prepared through electrostatic interaction between mercaptoacetic acid wrapped cdse quantum dots with negative charge and tio2-rgo hybrids with positive charge obtained via ultrasonic and acid treatments. electron microscopes and spectroscopes were used to characterize the function ...201424291752
development of a specific and sensitive enzyme-linked immunosorbent assay for the quantification of imatinib.imatinib is an oral tyrosine kinase inhibitor used for first-line treatment of chronic myeloid leukemia. therapeutic drug monitoring targeting trough plasma levels of about 1000 ng/ml may help to optimize imantinib's therapeutic effect. this paper reports a specific and sensitive enzyme-linked immunosorbent assay (elisa) for a pharmacokinetic evaluation of imatinib. anti-imatinib antibody was obtained by immunizing rabbits with an antigen conjugated with bovine serum albumin and succinimidyl 4-{ ...201324292055
a digital microfluidic electrochemical immunoassay.digital microfluidics (dmf) has emerged as a popular format for implementing quantitative immunoassays for diagnostic biomarkers. all previous reports of such assays have relied on optical detection; here, we introduce the first digital microfluidic immunoassay relying on electrochemical detection. in this system, an indium tin oxide (ito) based dmf top plate was modified to include gold sensing electrodes and silver counter/pseudoreference electrodes suitable for in-line amperometric measuremen ...201424292705
influence of iodothyronine conjugates of bovine serum albumin and horseradish peroxidase on enzyme immunosorbent assay of thyroid hormones.enzyme-linked immunosorbent assays (elisa's) reported for thyroxine (t₄) and 3,5,3'-triiodothyronine (t₃), involved coupling of the haptens through (i) carboxylic group to carrier protein for producing antibodies and (ii) amino group to detection labels. to improve the titer and specificity of antibodies, immunogens were prepared by coupling of carboxyl group to bovine serum albumin (bsa) either directly or through adipic acid dihydrazide (adh), after protecting amino group through acetylation o ...201424295178
effect of different combinations of antibodies and enzyme labels on elisa of progesterone.in steroid immunoassays, selection of right combination of antibody and enzyme-labeled antigen determine the sensitivity and specificity of elisa. antibodies raised against different positions of progesterone adopting heterologous systems were reported to provide better assays for progesterone. four different antibodies developed against progesterone-11α-hemiglutarate-bsa (p-11-hg-bsa), progesterone-11α-hemisuccinate-bsa (p-11-hs-bsa), progesterone-3-o-carboxymethyloxime-bsa (p-3-cmo-bsa), and p ...201424295179
a streptavidin-sog chimera for all-optical immunoassays.immunological detection has been developed into a sensitive and versatile technique and is based on two requisite elements: targeting antibodies and an indicator, usually in the form of horseradish peroxidase or alkaline phosphatase. the specificity and turnover rate of these enzymes provide an efficient means of signal amplification, but both require a stopping agent to prevent overdevelopment, which limits scalability to mechanized fluidic systems. as an alternative, we present a fully optical ...201424299010
cyclic-3-hydroxymelatonin (c3hom), a potent antioxidant, scavenges free radicals and suppresses oxidative reactions.cyclic 3-hydroxymelatonin (c3hom) is an immediate product of melatonin's interaction with reactive oxygen species. its presence has been detected in mice, rats and humans. in the current study, the antioxidant capacity and reducing power of this molecule have been systematically studied. c3hom is found to be a more potent antioxidant than melatonin or vitamin c in terms of its ability to scavenge the hydroxyl radical (ho.) and to recover oxidized horseradish peroxidase to its ground state. the a ...201424304286
diagnostic potential of anti-rncp-43 polyclonal antibodies for the detection of neospora caninum.neosporosis is a disease caused by the apicomplexan parasite neospora caninum, which is closely related to toxoplasma gondii. n. caninum infection represents an important cause of reproductive failure in sheep, goats, horses, and cattle worldwide. the diagnosis of neosporosis is based on the detection of pathogen-specific antibodies in animal sera or the presence of tissue cysts. however, morphological similarities and serological cross-reactivity between n. caninum and t. gondii can result in t ...201424310934
generation of selectable marker-free transgenic eggplant resistant to alternaria solani using the r/rs site-specific recombination system.marker-free transgenic eggplants, exhibiting enhanced resistance to alternaria solani , can be generated on plant growth regulators (pgrs)- and antibiotic-free ms medium employing the multi-auto-transformation (mat) vector, pmat21 - wasabi defensin , wherein isopentenyl transferase ( ipt ) gene is used as a positive selection marker.201424311155
an antioxidant bioinspired phenolic polymer for efficient stabilization of polyethylene.the synthesis, structural characterization and properties of a new bioinspired phenolic polymer (polycame) produced by oxidative polymerization of caffeic acid methyl ester (came) with horseradish peroxidase (hrp)-h2o2 is reported as a new sustainable stabilizer toward polyethylene (pe) thermal and photo-oxidative degradation. polycame exhibits high stability toward decarboxylation and oxidative degradation during the thermal processes associated with pe film preparation. characterization of pe ...201424313867
vaccine efficacy of transcutaneous immunization with amyloid β using a dissolving microneedle array in a mouse model of alzheimer's disease.vaccine therapy for alzheimer's disease (ad) based on the amyloid cascade hypothesis has recently attracted attention for treating ad. injectable immunization using amyloid β peptide (aβ) comprising 1-42 amino-acid residues (aβ1-42) as antigens showed therapeutic efficacy in mice; however, the clinical trial of this injected aβ1-42 vaccine was stopped due to the incidence of meningoencephalitis caused by excess activation of th1 cells infiltrating the brain as a serious adverse reaction. because ...201424315156
enzyme linked immuno mass spectrometric assay (elimsa).a new technology termed elimsa combines the specificity and enzymatic amplification of enzyme linked immunosorbent assay (elisa) with the sensitivity and flexibility of mass spectrometry (ms). at present, substrates for the reporter enzymes horseradish peroxidase (hrp) or alkaline phosphatase (ap) yield colored, fluorescent or luminescent products. the central concept of elimsa is that the reporter enzymes hrp and ap yield products that ionize efficiently with a high signal to noise ratio that c ...201424316356
increases in peroxide formation by the photosystem ii oxygen evolving reactions upon removal of the extrinsic 16, 22 and 33 kda proteins are reversed by cacl2 addition.this communication introduces a new spectrophotometric assay for the detection of peroxide generated by photosystem ii (ps ii) under steady state illumination in the presence of an electron acceptor. the assay is based on the formation of an indamine dye in a horseradish peroxidase coupled reaction between 3-(dimethylamino)benzoic acid and 3-methyl-2-benzothiazolinone hydrazone. using this assay, we found that as the o2 evolution activity of ps ii-enriched membrane fragments is decreased by trea ...199324317998
immobilization of water-soluble hrp within poly-n-isopropylacrylamide microgel particles for use in organic media.in the present work, the immobilization of enzymes within poly-n-isopropylacrylamide (p-nipam) microgels using the method of solvent exchange is applied to the enzyme horseradish peroxidase (hrp). when the solvent is changed from water to isopropanol, hrp is embedded within the polymer structure. after the determination of the immobilized amount of enzyme, an enhanced specific activity of the biocatalyst in isopropanol can be observed. karl fischer titration is used to determine the amount of wa ...201324320795
dietary omega-3 fatty acids enhance the b1 but not the b2 cell immune response in mice with antigen-induced peritonitis.the effects of omega-3 fatty acids on the adaptive immune response have mainly been analysed in vitro with varying results. how omega-3 fatty acids affect the adaptive immune response in vivo is largely unknown. this study examined the effects of dietary fish oil on the adaptive immune response in antigen-induced inflammation in mice, focusing on its effects on b cells and b cell subsets. mice were fed a control diet with or without 2.8% fish oil, immunized twice with methylated bsa (mbsa) and p ...201424332949
modulation of chondrocyte functions and stiffness-dependent cartilage repair using an injectable enzymatically crosslinked hydrogel with tunable mechanical properties.we developed an injectable hydrogel system to evaluate the effect of hydrogel stiffness on chondrocyte cellular functions in a three-dimensional (3d) environment and its subsequent influence on ectopic cartilage formation and early-stage osteochondral defect repair in a rabbit model. the hydrogels, composed of gelatin-hydroxyphenylpropionic acid (gtn-hpa) conjugate, were formed using oxidative coupling of hpa moieties catalyzed by hydrogen peroxide (h2o2) and horseradish peroxidase (hrp). the st ...201424333028
a young root-specific gene (army2) from horseradish encoding a myr ii myrosinase with kinetic preference for the root-specific glucosinolate gluconasturtiin.the pungent taste of horseradish is caused by isothiocyanates which are released from glucosinolates by myrosinases. these enzymes are encoded by genes belonging to one of two subfamilies, termed myr i and myr ii, respectively. a myr ii-type myrosinase gene was identified for the first time in horseradish. the gene termed army2 was only expressed in young roots. a full-length cdna encoding a myrosinase termed army2 was isolated and heterologously expressed in pichia pastoris. the recombinant his ...201424333031
introduction of a methoxymethyl side chain into p-phenylenediamine attenuates its sensitizing potency and reduces the risk of allergy induction.the strong sensitizing potencies of the most important primary intermediates of oxidative hair dyes, p-phenylenediamine (ppd) and p-toluylenediamine (ptd, i.e. 2-methyl-ppd) are well established. they are considered as the key sensitizers in hair dye allergic contact dermatitis. while modification of their molecular structure is expected to alter their sensitizing properties, it may also impair their color performance. with introduction of a methoxymethyl side chain we found the primary intermed ...201424333256
transient oxygen-glucose deprivation sensitizes brain capillary endothelial cells to rtpa at 4h of reoxygenation.thrombolysis treatment of acute ischemic stroke is limited by the pro-edematous and hemorrhagic effects exerted by reperfusion, which disrupts the blood-brain barrier (bbb) capillary endothelium in the infarct core. most studies of the ischemic bbb overlook the complexity of the penumbral area, where the affected brain cells are still viable following deprivation. our present objective was to examine in vitro the kinetic impact of reoxygenation on the integrity of ischemic bbb cells after oxygen ...201424333620
involvement of the single cul4 gene of chinese mitten crab eriocheir sinensis in spermatogenesis.the cullin-ring finger ligases (crls) are involved in the ubiquitin-mediated degradation of cell cycle regulators and play an important role in gametogenesis. cullin 4 (cul4) is a conserved core component of a new class of ubiquitin e3 ligase, and participates in the proteolysis of several regulatory proteins through the ubiquitin-proteasome pathway. the mammals encode two paralogs of cul4, cul4a and cul4b, and the two cul4 genes are functionally redundant. however, drosophila or other metazoans ...201424334119
ige and igg epitope mapping by microarray peptide-immunoassay reveals the importance and diversity of the immune response to the igg3 equine immunoglobulin.the presence of whole horse igg in therapeutic snake antivenom preparations of high purity is a contamination that can cause ige-mediated allergic reactions in patients. in this study, the immunodominant ige and igg-binding epitopes in horse heavy chain igg3 were mapped using arrays of overlapping peptides synthesized directly onto activated cellulose membranes. pooled human sera from patients with and without horse antivenom allergies were used to probe the membrane. we have demonstrated that, ...201424334152
electrochemical detection of francisella tularensis genomic dna using solid-phase recombinase polymerase amplification.solid-phase isothermal dna amplification was performed exploiting the homology protein recombinase a (reca). the system was primarily tested on maleimide activated microtitre plates as a proof-of-concept and later translated to an electrochemical platform. in both cases, forward primer for francisella tularensis holarctica genomic dna was surface immobilised via a thiol or an amino moiety and then elongated during the reca mediated amplification, carried out in the presence of specific target se ...201424334283
purification and basic biochemical characterization of 19 recombinant plant peroxidase isoenzymes produced in pichia pastoris.the plant enzyme horseradish peroxidase (hrp) is used in several important industrial and medical applications, of which especially biosensors and diagnostic kits describe an emerging field. although there is an increasing demand for high amounts of pure enzyme preparations, hrp is still isolated from the plant as a mixture of different isoenzymes with different biochemical properties. based on a recent next generation sequencing approach of the horseradish transcriptome, we produced 19 individu ...201424342173
facile preparation of glycoprotein-imprinted 96-well microplates for enzyme-linked immunosorbent assay by boronate affinity-based oriented surface imprinting.molecularly imprinted polymers (mips), as inexpensive and stable substitutes of antibodies, have shown great promise in immunoassays. glycoproteins are of significant diagnostic value. to facilitate the application of mips in clinical diagnostics, a general and facile imprinting method toward glycoproteins oriented for an enzyme-linked immunosorbent assay (elisa) in the form of a 96-well microplate is essential but has not been fully explored yet. in this study, a new method called boronate affi ...201424345219
multiplex chemiluminescent immunoassay for screening of mycotoxins using photonic crystal microsphere suspension array.a novel multiplex chemiluminescent mycotoxin immunoassay suspension array system was developed by combining the silica photonic crystal microspheres (spcms) encoding technique and a chemiluminescent immunoassay (clia) method. the spcms were used as a carrier of the suspension array and encoded by their reflectance peak positions, which overcome fluorescence photobleaching, and the potential interference between the encoding fluorescence and detection fluorescence. aflatoxin b1 (afb1), fumonisin ...201424352570
recombinant human lactoferrin as a biomaterial for bone tissue engineering: mechanism of antiapoptotic and osteogenic activity.lactoferrin is a bioactive globular protein with unique properties towards musculo-skeletal cells and anabolic to bone in vivo. even though the potent anti-apoptotic and osteogenic activity of lactoferrin has been reported, the mechanism of action has not been fully elucidated. the study demonstrates that the anti-apoptotic effect of rhlf towards mc3t3 pre-osteoblast cells is mediated by wnt5a/pka pathway and the stabilization of β-catenin by rhlf is dependent on pka/lrp6 signaling pathway. the ...201424352833
platelets do not express the oxidized or reduced forms of tissue factor.expression of tissue factor (tf) antigen and activity in platelets is controversial and dependent upon the laboratory and reagents used. two forms of tf were described: an oxidized functional form and a reduced nonfunctional form that is converted to the active form through the formation of an allosteric disulfide. this study tests the hypothesis that the discrepancies regarding platelet tf expression are due to differential expression of the two forms.201424361609
phagomagnetic immunoassay for the rapid detection of salmonella.this work explores the use of the phage p22 in a phagomagnetic immunoassay for the rapid detection of salmonella. the covalent attachment of wild-type phages was performed on two different magnetic carriers: carboxyl-activated magnetic nanoparticles (300 nm) and tosyl-activated magnetic microparticles (2.8 μm). the bacteria were captured and preconcentrated by the phage-modified magnetic particles, followed by the detection using specific anti-salmonella antibodies conjugated to horseradish pero ...201424362855
a novel amperometric alcohol biosensor developed in a 3rd generation bioelectrode platform using peroxidase coupled ferrocene activated alcohol oxidase as biorecognition system.alcohol oxidase (aox) with a two-fold increase in efficiency (kcat/km) was achieved by physical entrapment of the activator ferrocene in the protein matrix through a simple microwave based partial unfolding technique and was used to develop a 3rd generation biosensor for improved detection of alcohol in liquid samples. the ferrocene molecules were stably entrapped in the aox protein matrix in a molar ratio of ~3:1 through electrostatic interaction with the trp residues involved in the functional ...201424368229
plasma-derived mannose-binding lectin shows a direct interaction with c1-inhibitor.mbl-deficiency has been associated with an increased frequency and severity of infection, in particular in children and under immunocompromized conditions. in an open uncontrolled safety and pharmacokinetic mbl-substitution study using plasma-derived mbl (pdmbl) in mbl-deficient pediatric oncology patients, we found that despite mbl trough levels above 1.0μg/ml mbl functionality was not efficiently restored upon ex vivo testing. pdmbl showed c4-converting activity by itself, indicating the prese ...201424368318
surface coating-dependent cytotoxicity and degradation of graphene derivatives: towards the design of non-toxic, degradable nano-graphene.with the increasing interests of using graphene and its derivatives in the area of biomedicine, the systematic evaluation of their potential risks and impacts to biological systems is becoming critically important. in this work, we carefully study how surface coatings affect the cytotoxicity and extracellular biodegradation behaviors of graphene oxide (go) and its derivatives. although naked go could induce significant toxicity to macrophages, coating those two-dimensional nanomaterials with bio ...201424376215
amplified and multiplexed detection of dna using the dendritic rolling circle amplified synthesis of dnazyme reporter units.the amplified, highly sensitive detection of dna using the dendritic rolling circle amplification (rca) is introduced. the analytical platform includes a circular dna and a structurally tailored hairpin structure. the circular nucleic acid template includes a recognition sequence for the analyte dna (the tay-sachs mutant gene), a complementary sequence to the mg(2+)-dependent dnazyme, and a sequence identical to the loop region of the coadded hairpin structure. the functional hairpin in the syst ...201424377284
ultrasensitive electrochemical dna sensor based on the target induced structural switching and surface-initiated enzymatic polymerization.in this work, two electrochemical dna sensors was developed based on the target induced structural switching of stem-loop probe (slp) and surface initiated enzymatic polymerization (siep). both of the electrochemical dna sensors employed slps with the same sequence. however, one had a thiol label at its 3' terminal (the probe was named 3-slp and the sensor was named 3-slp-sens) and the other at its 5' terminal (the probe was named 5-slp and the sensor was named 5-slp-sens). in the initial state ...201424384265
novel gaa sequence variant c.1211 a>g reduces enzyme activity but not protein expression in infantile and adult onset pompe disease.pompe disease is a clinically and genetically heterogeneous autosomal recessive disorder caused by lysosomal acid α-glucosidase (gaa) deficiency. we report on two affected members of a non-consanguineous caucasian family, including a classical infantile-onset patient with severe cardiomyopathy (io) and his paternal grandmother with the adult-onset (ao) form. two compound heterozygous sequence variants of the gaa gene were identified in each patient by mutation analyses (io=c.1211a>g and c.1798c> ...201424384324
human endothelial progenitor cells internalize high-density lipoprotein.endothelial progenitor cells (epcs) originate either directly from hematopoietic stem cells or from a subpopulation of monocytes. controversial views about intracellular lipid traffic prompted us to analyze the uptake of human high density lipoprotein (hdl), and hdl-cholesterol in human monocytic epcs. fluorescence and electron microscopy were used to investigate distribution and intracellular trafficking of hdl and its associated cholesterol using fluorescent surrogates (bodipy-cholesterol and ...201324386159
combining polymers with the functionality of proteins: new concepts for atom transfer radical polymerization, nanoreactors and damage self-reporting materials.proteins are macromolecules with a great diversity of functions. by combining these biomolecules with polymers, exciting opportunities for new concepts in polymer sciences arise. this highlight exemplifies the aforementioned with current research results of our group. we review our discovery that the proteins horseradish peroxidase and hemoglobin possess atrpase activity, i.e. they catalyze atom transfer radical polymerizations. moreover, a permeabilization method for polymersomes is presented, ...201324388228
combination use of ferulic acid, ligustrazine and tetrahydropalmatine inhibits the growth of ectopic endometrial tissue: a multi-target therapy for endometriosis rats.ferulic acid (fa), ligustrazine (lz) and tetrahydropalmatine (thp) are separately isolated from chinese angelica, szechwan lovage rhizome and rhizoma in the jiawei-foshou-san formula, a popular traditional chinese medicine for irregular menses. it has been reported that the combination use of fa+lz+thp has similar effect on endometriosis, but the underlying mechanisms are unclear. this study was to investigate the combination effects and mechanisms of fa+lz+thp on endometriosis rats.201424389027
ultrasensitive immunoassay based on electrochemical measurement of enzymatically produced polyaniline.a novel ultrasensitive immunoassay method was developed based on the electrochemical measurement of polyaniline, which was catalytically produced by horseradish peroxidase-functionalized gold nanoparticle (hrp-au np) probe at an immunosensor. the immunosensor was prepared step-wise by first modifying the electrode with reduced graphene oxide (rgo)/au nps nanocomposite followed by the immobilization of capture antibodies on its surface. after performing a sandwich immunoreaction, the quantitative ...201424392763
realization of an ultra-sensitive hydrogen peroxide sensor with conductance change of horseradish peroxidase-immobilized polyaniline and investigation of the sensing mechanism.in this study, we fabricate an ultra-sensitive hydrogen peroxide sensor by using horseradish peroxidase (hrp)-immobilized conducting polymer, polyaniline (pani). with the proposed detection mechanism, hydrogen peroxide first oxidizes hrp, which then oxidizes polyaniline, thus resulting in decreased conductivity of the polyaniline thin film. the reduced hrp can be further oxidized by hydrogen peroxide and the cycle of the oxidation/reduction would continue until all hydrogen peroxide are reacted, ...201424398124
increased permeability of blood-brain barrier is mediated by serine protease during cryptococcus meningitis.to determine the role of serine protease in the disruption of the blood-brain barrier (bbb) during cryptococcus neoformans meningitis.201424398759
sensitive chemiluminescence immunoassay for e. coli o157:h7 detection with signal dual-amplification using glucose oxidase and laccase.a novel, sensitive chemiluminescence (cl) immunoassay for escherichia coli o157:h7 detection with signal dual-amplification using glucose oxidase (gox) and laccase was investigated. the method was based on the characterization of a luminol-h2o2-laccase reaction. compared with the horseradish peroxidase-based biosensor, laccase exhibited high catalytic activity in strong alkaline medium, which was compatible with the luminol system. the capture antibody was immobilized onto the magnetic bead (mb) ...201424405233
detection of single-digit foodborne pathogens with the naked eye using carbon nanotube-based multiple cycle signal amplification.a carbon nanotube (cnt)-based multiple cycle signal amplification strategy has been demonstrated for detection of single-digit foodborne pathogens with the naked eye. in the present design, cnts are used as carriers for loading numerous horseradish peroxidase (hrp) and concanavalin a (cona) tags, and multiple cycle signal amplification is achieved through the biotinylated anti-hrp antibody and avidin-hrp.201424406326
tfdp3 was expressed in coordination with e2f1 to inhibit e2f1-mediated apoptosis in prostate cancer.tfdp3 has been previously identified as an inhibitor of e2f molecules. it has been shown to suppress e2f1-induced apoptosis dependent p53 and to play a potential role in carcinogenesis. however, whether it indeed helps cancer cells tolerate apoptosis stress in cancer tissues remains unknown. tfdp3 expression was assessed by rt-pcr, in situ hybridization and immunohistochemistry in normal human tissues, cancer tissues and prostate cancer tissues. the association between tfdp3 and e2f1 in prostate ...201424406621
immobilization of horseradish peroxidase in phospholipid-templated titania and its applications in phenolic compounds and dye removal.in this study, horseradish peroxidase (hrp) was encapsulated in phospholipid-templated titania particles through the biomimetic titanification process and used for the treatment of wastewater polluted with phenolic compounds and dye. the encapsulated hrp exhibited improved thermal stability, a wide range of ph stability and high tolerance against inactivating agents. it was observed an increase in km value for the encapsulated hrp (8.21 mm) when compared with its free counterpart. for practical ...201424411438
the use of trametes versicolor laccase for the polymerization of aniline in the presence of vesicles as templates.the enzymatic polymerization of aniline to polyaniline (pani) with trametes versicolor laccase (tvl) as catalyst and dioxygen (o₂) as oxidant was investigated in an aqueous medium containing unilamellar vesicles with an average diameter of about 80 nm formed from aot (=sodium bis(2-ethylhexyl) sulfosuccinate). compared to the same reaction carried out with horseradish peroxidase isoenzyme c (hrpc) as catalyst and hydrogen peroxide (h₂o₂) as oxidant, notable differences were found in the kinetics ...201424411448
highly sensitive and multiple dna biosensor based on isothermal strand-displacement polymerase reaction and functionalized magnetic microparticles.a universal, highly sensitive and selective chemiluminescence (cl) imaging method has been developed for high throughput detection of dna. after molecular beacon (mb) hybridized with the target dna, the biotin-labeled primer was attached to a magnetic microparticle (mmp) surface by hybridization with the stem part of the mb to initiate a polymerization of dna strand, which led to the release of the target and another polymerization cycle. thus the polymerization produced the multiplication of bi ...201424412765
the bound auxins: protection of indole-3-acetic acid from peroxidase-catalyzed oxidation.indole-3-acetic acid (iaa) was oxidized by horseradish peroxidase, but ester and amide conjugates of iaa were not degraded. addition of indoleacetyl-myo-inositol, indoleacetyl-l-aspartate, indoleacetylglycine, indoleacetyl-l-alanine, indoleacetyl-d-alanine, or indoleacetyl-β-alanine did not affect the rate of oxidation of iaa by horseradish peroxidase. peroxidase preparations from pisum sativum l. and zea mays l. behaved similarly in that they rapidly oxidized iaa, but not conjugates found in th ...197824414261
lignin synthesis: the generation of hydrogen peroxide and superoxide by horseradish peroxidase and its stimulation by manganese (ii) and phenols.the enzyme horseradish peroxidase (ec 1.11.1.7) catalyses oxidation of nadh. nadh oxidation is prevented by addition of the enzyme superoxide dismutase (ec 1.15.1.1) to the reaction mixture before adding peroxidase but addition of dismutase after peroxidase has little inhibitory effect. catalase (ec 1.11.1.6) inhibits peroxidase-catalysed nadh oxidation when added at any time during the reaction. apparently the peroxidase uses hydrogen peroxide (h2o2) generated by non-enzymic breakdown of nadh t ...197824414365
anthraquinone dyes decolorization capacity of anamorphic bjerkandera adusta ccbas 930 strain and its hrp-like negative mutants.cultures of the anamorphic fungus bjerkandera adusta ccbas 930 decolorizing, in stationary cultures, 0.01 % solutions of carminic acid and poly r-478, were characterised by a strong increase in the activity of the horseradish peroxidase (hrp-like) and manganese-dependent peroxidase (mnp) at a low activity of lignin peroxidase. genotypically modified mutants of b. adusta ccbas 930: 930-5 and 930-14, with total or partial loss of decolorization capabilities relative to anthraquinonic dyes, showed ...201424415463
amplified electrochemiluminescent aptasensor using mimicking bi-enzyme nanocomplexes as signal enhancement.in this work, a sandwich-type electrochemiluminescence (ecl) aptasensor for ultrasensitive detection of thrombin (tb) was designed based on mimicking bi-enzyme cascade catalysis to in situ generate coreactant of dissolved oxygen (o2) for signal amplification. we utilized hollow au nanoparticles (haunps) as carriers to immobilize glucose oxidase nanoparticles (goxnps) and pt nanoparticles (ptnps) by electrostatic adsorption. then, the detection aptamer of thrombin (tba 2) was immobilized on the p ...201424418132
highly sensitive impedimetric immunosensor based on single-walled carbon nanohorns as labels and bienzyme biocatalyzed precipitation as enhancer for cancer biomarker detection.a novel sandwich-type electrochemical immunosensor based on functionalized nanomaterial labels and bienzyme (horseradish peroxidase and glucose oxidase) biocatalyzed precipitation was developed for the detection of α-fetoprotein (afp). the enzymes linked to functionalized nanomaterials as biocatalysts could accelerate the oxidation of 4-chloro-1-naphthol (4-cn) by h2o2 to yield the insoluble product on the electrode surface; the mass loading of the precipitates on the device led to a significant ...201424419078
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