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[dendritic projections from meridian-related motoneurons to sympathic preganglion neurons in the spinal cord of rats].previous studies indicated a close involvement of reflex activities of motoneurons in the spinal cord in the mechanism of meridian phenomena. the present study was designed to investigate the dendrite projections of meridian-related motoneurons among the motoneurons and sympathetic preganglionic neurons in the spinal cord.201324579358
an in vitro spectrophotometric analysis of the penetration of bleaching agent into the pulp chamber of intact and restored teeth.to investigate the pulp chamber penetration of bleaching agent in intact teeth and teeth following restorative procedure.201324551727
autophagy of iron-binding proteins may contribute to the oxidative stress resistance of arpe-19 cells.the objective of this study was to elucidate possible reasons for the remarkable resistance of human retinal pigment epithelial (rpe) cells to oxidative stress. much oxidative damage is due to hydrogen peroxide meeting redox-active iron in the acidic and reducing lysosomal environment, resulting in the production of toxic hydroxyl radicals that may oxidize intralysosomal content, leading to lipofuscin (lf) formation or, if more extensive, to permeabilization of lysosomal membranes. formation of ...201324512774
[influence of nogo extracellular peptide residues 1-40 gene modification on survival and differentiation of neural stem cells after transplantation].to investigate the influence of nogo extracellular peptide residues 1-40 (nep1-40) gene modification on the survival and differentiation of the neural stem cells (nscs) after transplantation.201324501899
detoxification of pesticides aqueous solution using horseradish peroxidase.there are pesticide residues in agriculture wastewater and that compounds must be removed before discharge of wastewater in native waters. thus the aim of this study was to remove toxic pesticide in waste water by the addition of horseradish peroxidase enzyme. the process of pesticide (methyl-parathion (o,o-diethyl- o-4-nitro-phenylthiophosphate), atrazine (1-chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine) and triazophos (o,o-diethyl o-1-phenyl-1h-1,2,4- triazol-3-yl phosphorothioate) remov ...201324498792
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
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
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
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
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
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
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
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
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
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
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
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
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
a novel and efficient polymerization of lignosulfonates by horseradish peroxidase/h(2)o(2) incubation.lignosulfonates(lss), by-products from chemical pulping processes, are low-value products with limited dispersion properties. the ability of commercially available horseradish peroxidase (hrp) to polymerize ls macromolecules and improve the dispersion properties of lss was investigated. the polymerization of lss proceeded efficiently under mild reaction conditions in an aqueous solution with hrp/h2o2. gel permeation chromatography showed a significant increase in weight-average molecular weight ...201324196582
preparation of boronate-functionalized molecularly imprinted monolithic column with polydopamine coating for glycoprotein recognition and enrichment.a novel imprinting strategy using reversible covalent complexation of glycoprotein was described for creating glycoprotein-specific recognition cavities on boronate-functionalized monolithic column. based on it, a molecularly imprinted monolithic column was prepared by self-polymerization of dopamine (da) on the surface of 4-vinylphenylboronic acid (vpba)-based polymeric skeletons after reversible immobilization of horseradish peroxidase (hrp). due to the combination of boronate affinity and sur ...201324192150
scavenging of free-radical metabolites of aniline xenobiotics and drugs by amino acid derivatives: toxicological implications of radical-transfer reactions.we investigated a novel scavenging mechanism of arylamine free radicals by poly- and monoaminocarboxylates. free radicals of arylamine xenobiotics and drugs did not react with oxygen in peroxidase-catalyzed reactions; however, they showed marked oxygen uptake in the presence of an aminocarboxylate. these free-radical intermediates were identified using the spin trap 5,5-dimethyl-1-pyrroline-n-oxide (dmpo) and electron paramagnetic resonance (epr) spectrometry. diethylenetriaminepentaacetic acid ...201324191655
horseradish peroxidase inactivation: heme destruction and influence of polyethylene glycol.horseradish peroxidase (hrp) mediates efficient conversion of many phenolic contaminants and thus has potential applications for pollution control. such potentially important applications suffer however from the fact that the enzyme becomes quickly inactivated during phenol oxidation and polymerization. the work here provides the first experimental data of heme consumption and iron releases to support the hypothesis that hrp is inactivated by heme destruction. product of heme destruction is iden ...201324185130
celiac disease serum markers and recurrent pregnancy loss.celiac disease has been associated with numerous unfavorable health outcomes, including pregnancy complications such as infertility, preterm birth, and preeclampsia. however, the association between celiac disease and recurrent pregnancy loss (rpl) remains uncertain. our purpose was to compare serum markers of celiac disease in women with and without rpl. therefore, we performed a case-control study of 116 women with unexplained recurrent pregnancy loss and 116 age-matched controls. maternal ser ...201324176553
temperature-controlled encapsulation and release of an active enzyme in the cavity of a self-assembled dna nanocage.we demonstrate temperature-controlled encapsulation and release of the enzyme horseradish peroxidase using a preassembled and covalently closed three-dimensional dna cage structure as a controllable encapsulation device. the utilized cage structure was covalently closed and composed of 12 double-stranded b-dna helices that constituted the edges of the structure. the double stranded helices were interrupted by short single-stranded thymidine linkers constituting the cage corners except for one, w ...201324168393
an ultrasensitive chemiluminescent immunosensor for the detection of human leptin using hemin/g-quadruplex dnazymes-assembled signal amplifier.in this work, we reported a sensitive chemiluminescent immunosensor for the detection of human leptin by using hemin/g-quadruplex dnazymes to amplify detection signal. in this sensing system, the primary antibody (anti-human leptin) was firstly bound to the 96-well plates, and human leptin and biotinylated secondary antibody were successively combined to form sandwich-type immune complex through specific interactions. then streptavidin labeled with hemin/g-quadruplex dnazymes was assembled to th ...201324148479
electrochemical immunoassay for carcinoembryonic antigen using gold nanoparticle-graphene composite modified glassy carbon electrode.carcinoembryonic antigen (cea), which is typically associated with certain tumors and developing fetus, is widely used as a clinical tumor marker for some familiar cancers. in this work, a simple and sensitive electrochemical cea sensor was developed by employing immunoreaction. gold nanoparticle-decorated graphene composites (au-gn) were successfully synthesized based on the reduction of haucl4 in the presence of graphene. horseradish peroxidase-labeled anti-cea antibody (hrp-anti-cea) and hrp ...201324148478
rapid high-throughput analysis of ochratoxin a by the self-assembly of dnazyme-aptamer conjugates in wine.we report a new label-free colorimetric aptasensor based on dnazyme-aptamer conjugate for rapid and high-throughput detection of ochratoxin a (ota, a possible human carcinogen, group 2b) in wine. two oligonucleotides were designed for this detection. one is n1 for biorecognition, which includes two adjacent sequences: the ota-specific aptamer sequence and the horseradish peroxidase (hrp)-mimicking dnazyme sequence. the other is a blocking dna (b2), which is partially complementary to a part of t ...201324148439
role of triton x-100 in chemiluminescent enzyme immunoassays capable of diagnosing genetic disorders.the use of triton x surfactants in developing 1,1'-oxalylimidazole chemiluminescent enzyme immunoassays (odi ceis) with extended linear response range for the quantification of unconjugated estriol (ue3), alpha-fetoprotein (afp), and human chorionic gonadotropin (hcg) is reported for the first time. the wider linear dynamic range in odi cleia results from triton x series (e.g., triton x-100, -114, -405, -705) acting as an inhibitor in the interaction between amplex red (hydrophobic substrate) an ...201324148422
determination of okadaic acid in shellfish by using a novel chemiluminescent enzyme-linked immunosorbent assay method.a direct competitive chemiluminescent enzyme-linked immunosorbent assay (cl-elisa) was developed to determine okadaic acid (oa). concentrations of the capture monoclonal anti-oa antibodies, conjugate of oa-hrp and a composition of blocking buffers were varied to optimize the assay condition. the values of ic10, ic50 and working range (ic20-ic80) for cl-elisa were 0.01, 0.07, and 0.03-0.2 ng/ml, respectively. additionally, the analytical recovery values of cl-elisa from 3 shellfish spiked samples ...201324148413
selective conjugation of proteins by mining active proteomes through click-functionalized magnetic nanoparticles.superparamagnetic iron oxide nanoparticles (spions) coated with azide groups were functionalized at the surface with biotin (biotin@spions) and cysteine protease inhibitor e-64 (e-64@spions) with the purpose of developing nanoparticle-based assays for identifying cysteine proteases in proteomes. magnetite particles (ca. 6 nm) were synthesized by microwave-assisted thermal decomposition of iron acetylacetonate and subsequently functionalized following a click chemistry protocol to obtain biotin a ...201324143894
high glucose enhances lps-stimulated human pmvec hyperpermeability via the no pathway.chronic hyperglycemia is an established risk factor for endothelial damage. it remains unclear, however, whether brief hyperglycemic exposure exacerbates the damage to vascular endothelial cells induced by endotoxin. we hypothesize that brief hyperglycemic exposure enhances the permeability of the endothelium following stimulation with lipopolysaccharide (lps). correlations between modulation of nitric oxide synthase (nos) pathways and altered endothelial homeostasis have been studied and demons ...201324137189
vegf111b, a new member of vegfxxxb isoforms and induced by mitomycin c, inhibits angiogenesis.vascular endothelial growth factor (vegf-a) stimulating angiogenesis is required for tumor growth and progression. the conventional vegf-a isoforms have been considered as pro-angiogenic factors. another family of vegf-a isoforms generated by alternative splicing, termed vegfxxxb isoforms, has anti-angiogenic property, exemplified by vegf165b. here, we identify a new number of vegfxxx family-vegf111b induced by mitomycin c, although not detected in mitomycin c-unexposed ovarian cancer cells. sko ...201324125722
laminated paper-based analytical devices (lpad) with origami-enabled chemiluminescence immunoassay for cotinine detection in mouse serum.laminated paper-based analytical devices (lpad) with origami-enabled chemiluminescence immunoassay have been developed for the detection of cotinine, a secondhand smoke (shs) biomarker. the devices were fabricated by a craft-cutter to define flow channels, followed by lamination. this approach of cutting/lamination to fabricate lpad is very similar to making an identification card, offering advantages in simplicity and rugged backing when compared to the common method of patterning paper using s ...201324117197
immobilization of horseradish peroxidase on electrospun microfibrous membranes for biodegradation and adsorption of bisphenol a.horseradish peroxidase (hrp) from roots of horseradish (amoracia rusticana) was successfully immobilized on novel enzyme carriers, poly(methyl methacrylate-co-ethyl acrylate) (pmma cea) microfibrous membranes, and used for removal of bisphenol a from water. pmma cea fibrous membranes (pfm) with fiber diameters of 300-500 nm, were fabricated by electrospinning. hrp was covalently immobilized on the surface of microfibers previously activated by polyethylenimine and glutaraldehyde. hrp loading rea ...201324096278
postnatal development of glycine receptor subunits α1, α2, α3, and β immunoreactivity in multiple brain stem respiratory-related nuclear groups of the rat.the respiratory system is immature at birth and significant development occurs postnatally. a critical period of respiratory development occurs in rats around postnatal days 12-13, when enhanced inhibition dominates over suppressed excitation. the mechanisms underlying the heightened inhibition are not fully understood. the present study tested our hypothesis that the inhibition is marked by a switch in glycine receptor subunits from neonatal to adult form around the critical period. an in-depth ...201324080401
on the use of l-012, a luminol-based chemiluminescent probe, for detecting superoxide and identifying inhibitors of nadph oxidase: a reevaluation.l-012, a luminol-based chemiluminescent (cl) probe, is widely used in vitro and in vivo to detect nadph oxidase (nox)-derived superoxide (o2(*-)) and identify nox inhibitors. yet understanding of the free radical chemistry of the l-012 probe is still lacking. we report that peroxidase and h2o2 induce superoxide dismutase (sod)-sensitive, l-012-derived cl in the presence of oxygen. o2(*-) alone does not react with l-012 to emit luminescence. self-generated o2(*-) during oxidation of l-012 and lum ...201324080119
involvement of the spinal nalp1 inflammasome in neuropathic pain and aspirin-triggered-15-epi-lipoxin a4 induced analgesia.neuroinflammation plays an important role in nerve-injury-induced neuropathic pain, but the explicit molecular mechanisms of neuroinflammation in neuropathic pain remain unclear. as one of the most critical inflammatory cytokines, interleukin-1β (il-1β) has been regarded as broadly involved in the pathology of neuropathic pain. the inflammasome caspase-1 platform is one primary mechanism responsible for the maturation of il-1β. lipoxins, a type of endogenous anti-inflammatory lipid, have proved ...201324076348
epithelial cell adhesion molecule (epcam) is associated with prostate cancer metastasis and chemo/radioresistance via the pi3k/akt/mtor signaling pathway.prostate cancer (cap) is the second leading malignancy in men. the role of epithelial cell adhesion molecule (epcam), also known as cd326, in cap progression and therapeutic resistance is still uncertain. here, we aimed to investigate the roles of epcam in cap metastasis and chemo/radioresistance. expression of epcam in cap cell lines and human cap tissues was assessed using immunofluorescence and immunohistochemistry, respectively. epcam was knocked down (kd) in pc-3, du145 and lncap-c4-2b cell ...201324076216
changes in synaptic transmission and protein expression in the brains of adult offspring after prenatal inhibition of the kynurenine pathway.during early brain development, n-methyl-d-aspartate (nmda) receptors are involved in cell migration, neuritogenesis, axon guidance and synapse formation, but the mechanisms which regulate nmda receptor density and function remain unclear. the kynurenine pathway of tryptophan metabolism includes an agonist (quinolinic acid) and an antagonist (kynurenic acid) at nmda receptors and we have previously shown that inhibition of the pathway using the kynurenine-3-monoxygenase inhibitor ro61-8048 in la ...201324076085
reflux induces dna strand breaks and expression changes of mmp1+9+14 in a human miniorgan culture model.gastroesophageal reflux disease has been implicated in the pathogenesis of adenocarcinoma of the oesophagus. the same applies to laryngopharyngeal reflux (lpr) and squamous cell cancer of the head and neck, but so far, this link has not been proven. the impact of low ph and bile acids has not been studied extensively in cells other than oesophageal cancer cell lines and tissue. the aims of this study were to investigate the pathogenic potential of reflux and its single components on the mucosa o ...201324075964
a fluorescent peroxidase probe increases the sensitivity of commercial elisas by two orders of magnitude.the low detection sensitivity of enzyme linked immunosorbent assays (elisas) is a central problem in science and limits progress in multiple areas of biology and medicine. in this report we demonstrate that the hydrocyanines, a family of fluorescent reactive oxygen species (ros) probes, can act as turn on fluorescent horseradish peroxidase (hrp) probes and thereby increase the sensitivity of conventional elisas by two orders of magnitude.201324071916
application of bispecific antibody against antigen and hapten for immunodetection and immunopurification.we present a bispecific antibody that recognizes an antigen and a hapten and can be applied to various biological assays, including immunoblotting and immunoprecipitation. in immunoblot analysis of serum, an anti-c5 × anti-cotinine bispecific tandem single-chain variable fragment (scfv)-fc fusion protein and cotinine-conjugated horseradish peroxidase (hrp) generated a clean signal without the high background that was observed in a parallel experiment using hrp-conjugated goat anti-rabbit immunog ...201324071736
selective permeabilization of the blood-brain barrier at sites of metastasis.effective chemotherapeutics for primary systemic tumors have limited access to brain metastases because of the blood-brain barrier (bbb). the aim of this study was to develop a strategy for specifically permeabilizing the bbb at sites of cerebral metastases.201324108809
myosin ii regulates activity dependent compensatory endocytosis at central synapses.recent evidence suggests that endocytosis, not exocytosis, can be rate limiting for neurotransmitter release at excitatory cns synapses during sustained activity and therefore may be a principal determinant of synaptic fatigue. at low stimulation frequencies, the probability of synaptic release is linked to the probability of synaptic retrieval such that evoked release results in proportional retrieval even for release of single synaptic vesicles. the exact mechanism by which the retrieval rates ...201324107946
luminescence amplification by enzymatic eu2+ oxidation to eu3+ for time-resolved peroxidase activity measurement.a novel peroxidase activity assay was developed for horseradish peroxidase (hrp) and myeloperoxidase (mpo), in which substrate eu(2+) was catalytically oxidized to eu(3+), and the eu(3+) luminescence was enhanced by the addition of sensitizer 4,4'-bis(1″,1″,1″,2″,2″,3″,3″-hepatafluoro-4″,6″-hexanedione-6″-yl)chlorosulfo-o-terphenyl (bhhct) for time-resolved measurement of the bhhct-eu(3+) complex. since bhhct-eu(3+) has a long lifetime (more than 500 μs), typical of eu(3+) oxidation state, and t ...201324107562
prevention of hemolysis-induced organ damage by nutritional activation of the vagal anti-inflammatory reflex*.acute hemolysis is associated with organ damage, inflammation, and impaired vascular function. stimulation of the cholecystokinin-1 receptor-dependent vagal anti-inflammatory reflex with lipid-rich enteral nutrition was demonstrated to prevent tissue damage and attenuate inflammation. this study investigates the effects of nutritional activation of the vagal anti-inflammatory reflex on organ integrity, systemic inflammation, and microcirculation during hemolysis.201324105450
covalent bond formation between amino acids and lignin: cross-coupling between proteins and lignin.the present study characterized the products formed from the reaction of amino acids and in turn, proteins, with lignin resulting in cross-coupling. when added to reaction mixtures containing coniferyl alcohol, horseradish peroxidase and h2o2, three amino acids (cys, tyr, and thr) are able to form adducts. the low molecular weight products were analyzed by hplc and from each reaction mixture, one product was isolated and analyzed by lc/ms. lc/ms results are consistent with bond formation between ...201324099658
grp78 secreted by tumor cells stimulates differentiation of bone marrow mesenchymal stem cells to cancer-associated fibroblasts.cancer-associated fibroblasts (cafs), one type of tumor-associated stromal cells, have been shown to provide a favorable environment for the malignant tumor progression. extensive reports have demonstrated that mesenchymal stem cells (mscs) can function as precursors for cafs. however, the mechanisms by which tumor cells induce the transition of mscs to cafs have not been well established. grp78, traditionally known as an endoplasmic reticulum (er) chaperone, has been identified to overexpress i ...201324113381
quantum dots based electrochemiluminescent immunosensor by coupling enzymatic amplification for ultrasensitive detection of clenbuterol.an ultrasensitive electrochemiluminescence (ecl) immunosensor based on cdse quantum dots (qds) has been designed for the detection of clenbuterol. the immunosensor was fabricated by layer by layer and characterized with atomic force microscopic images (afm) and electrochemical impedance spectra (eis). in oxygen-saturated ph=9.0 tris-hcl buffer, a strong ecl emission of qds could be observed during the cathodic process due to the h2o2 product from electrochemical reduction of dissolved oxygen. up ...201324070487
eicosapentaenoic acid enhances heat stress-impaired intestinal epithelial barrier function in caco-2 cells.dysfunction of the intestinal epithelial tight junction (tj) barrier is known to have an important etiologic role in the pathophysiology of heat stroke. n-3 polyunsaturated fatty acids (pufas), including eicosapentaenoic acid (epa) and docosahexaenoic acid (dha), play a role in maintaining and protecting the tj structure and function. this study is aimed at investigating whether n-3 pufas could alleviate heat stress-induced dysfunction of intestinal tight junction.201324066055
[characterization of stability of polypeptides and glycoproteins by capillary electrophoresis].a capillary electrophoresis (ce) method was developed for the stability characterization of polypeptides and glycoproteins. angiotensin ii (ang ii), phytagglutinin (pha), bovine thrombin (b-thr), human thrombin (h-thr) and horseradish peroxidase (hrp) were used as polypeptide and glycoprotein mode molecules. the parameters affecting the analysis efficiency for ang ii, such as sample concentration, running buffer, ph and ionic strength of sample solution were optimized, as for the glycoprotein, c ...201324063193
[preparation of organic-inorganic hybrid boronate affinity monolith via thiol-ene click reaction for specific capture of glycoproteins].a novel strategy for the preparation of the organic-inorganic hybrid boronate affinity monolith was developed via the "thiol-ene" click reaction. a thiol group-modified silica monolith was first synthesized via the sol-gel process by the in situ co-condensation with tetramethoxysilane (tmos) and 3-mercaptopropyltrimethoxysilane (mptms) as precursors. then 3-acrylamidophenylboronic acid (aapba) was covalently immobilized on the hybrid monolith via the "thiol-ene" click reaction to form aapba-sili ...201324063191
validated detection of anti-gd2 antibody ch14.18/cho in serum of neuroblastoma patients using anti-idiotype antibody ganglidiomab.human/mouse chimeric monoclonal antibody (mab) ch14.18 is directed against disialoganglioside gd2 and has demonstrated activity and efficacy in high-risk neuroblastoma (nb). for the purpose of industrial production, ch14.18 was manufactured in chinese hamster ovarian cells (ch14.18/cho) in order to facilitate clinical trials in europe. to determine immunopharmacological effects of ch14.18 in preclinical models and clinical trials, a validated method of quantitative detection of ch14.18/cho in se ...201324055592
anionic polythiophene derivative as peroxidase mimetics and their application for detection of hydrogen peroxide and glucose.in this paper, we discovered that the anionic polythiophenes derivative, poly[2-(3-thienyl)ethyloxy-4-butylsulfonate] (ptebs), possesses intrinsic peroxidase-like activity that can catalyze the reaction of peroxidase substrate 3,3',5,5'-tetramethylbenzidine (tmb) in the presence of h2o2 to produce a blue color reaction, which provides colorimetric detection of h2o2. ptebs exhibits several advantages such as high catalytic efficiency, good stability, and rapid response over horseradish peroxidase ...201324054671
3-(10'-phenothiazinyl)propionic acid is a potent primary enhancer of peroxidase-induced chemiluminescence and its application in sensitive elisa of methylglyoxal-modified low density lipoprotein.using a full factorial design the optimization of experimental conditions of enhanced chemiluminescence reaction (ecr) catalyzed by horseradish peroxidase (hrp) in the presence of 3-(10'-phenothiazinyl)propionic acid (ppa) as a primary enhancer was performed. the effect of concentrations of ppa, hydrogen peroxide, morph, luminol, and tris on a ratio of peroxidase-catalyzed cl to background was studied. the detection limit value of hrp in ecr with ppa was 0.09 pm. using ppa the ultra-sensitive ch ...201324054611
a synthetic compound, 4-acetyl-3-methyl-6-(3,4,5-trimethoxyphenyl)pyrano[3,4-c]pyran-1,8-dione, ameliorates ovalbumin-induced asthma.eosinophilia is one of the characteristic signs of allergic inflammation. massive migration of eosinophils to the airways can cause epithelial tissue injury, contraction of airway smooth muscle and increased bronchial responsiveness. previously, we discovered a new compound, 1h,8h-pyrano[3,4-c]pyran-1,8-dione (ppy), derived from the fruit of vitex rotundifolia l. and evaluated its anti-inflammatory and anti-asthmatic properties. in this study, we synthesized a new modified compound, 4-acetyl-3-m ...201324054491
overview of bacterial cellulose composites: a multipurpose advanced material.bacterial cellulose (bc) has received substantial interest owing to its unique structural features and impressive physico-mechanical properties. bc has a variety of applications in biomedical fields, including use as biomaterial for artificial skin, artificial blood vessels, vascular grafts, scaffolds for tissue engineering, and wound dressing. however, pristine bc lacks certain properties, which limits its applications in various fields; therefore, synthesis of bc composites has been conducted ...201324053844
multiplex acute leukemia cytosensing using multifunctional hybrid electrochemical nanoprobes at a hierarchically nanoarchitectured electrode interface.we have developed a robust, nanobiotechnology-based electrochemical cytosensing approach with high sensitivity, selectivity, and reproducibility toward the simultaneous multiplex detection and classification of both acute myeloid leukemia and acute lymphocytic leukemia cells. the construction of the electrochemical cytosensor involves the hierarchical assembly of dual aptamer-functionalized, multilayered graphene-au nanoparticle electrode interface and the utilization of hybrid electrochemical n ...201324056731
mechanism of protein decarbonylation.ligand/receptor stimulation of cells promotes protein carbonylation that is followed by the decarbonylation process, which might involve thiol-dependent reduction (c.m. wong et al., circ. res. 102:301-318; 2008). this study further investigated the properties of this protein decarbonylation mechanism. we found that the thiol-mediated reduction of protein carbonyls is dependent on heat-labile biologic components. cysteine and glutathione were efficient substrates for decarbonylation. thiols decre ...201324044890
surface-initiated dehydrogenative polymerization of monolignols: a quartz crystal microbalance with dissipation monitoring and atomic force microscopy study.this work highlights a real-time and label-free method to monitor the dehydrogenative polymerization of monolignols initiated by horseradish peroxidase (hrp) physically immobilized on surfaces using a quartz crystal microbalance with dissipation monitoring (qcm-d). the dehydrogenative polymer (dhp) films are expected to provide good model substrates for studying ligninolytic enzymes. the hrp was adsorbed onto gold or silica surfaces or onto and within porous desulfated nanocrystalline cellulose ...201324032374
plasmon-enhanced enzyme-linked immunosorbent assay on large arrays of individual particles made by electron beam lithography.ultrasensitive biosensing is one of the main driving forces behind the dynamic research field of plasmonics. we have previously demonstrated that the sensitivity of single nanoparticle plasmon spectroscopy can be greatly enhanced by enzymatic amplification of the refractive index footprint of individual protein molecules, so-called plasmon-enhanced enzyme-linked immunosorbent assay (elisa). the technique, which is based on generation of an optically dense precipitate catalyzed by horseradish per ...201324025047
microfluidic tool coupled with electrochemical assay for detection of lactoferrin isolated by antibody-modified paramagnetic beads.lactoferrin (lf) is approximately 80 kda iron-binding protein, which is important part of saliva and other body fluids. due to its ability to bind metal ions, it has many biologically important functions. in this study, a method for the isolation of lf from a biological sample using robotically prepared antibody-modified paramagnetic particles was developed using robotic pipetting station. the method consisted of the following optimised steps. protein g was bound on the paramagnetic particles, o ...201324024242
measurement of hne-protein adducts in human plasma and serum by elisa-comparison of two primary antibodies.there is increasing evidence that non-enzymatic post-translational protein modifications might play key roles in various diseases. these protein modifications can be caused by free radicals generated during oxidative stress or by their products generated during lipid peroxidation. 4-hydroxynonenal (hne), a major biomarker of oxidative stress and lipid peroxidation, has been recognized as important molecule in pathology as well as in physiology of living organisms. therefore, its detection and qu ...201324024156
oxidized lipids activate autophagy in a jnk-dependent manner by stimulating the endoplasmic reticulum stress response.excessive production of unsaturated aldehydes from oxidized lipoproteins and membrane lipids is a characteristic feature of cardiovascular disease. our previous studies show that unsaturated lipid peroxidation-derived aldehydes such as 4-hydroxy-trans-2-nonenal (hne) promote autophagy in rat aortic smooth muscle cells (rasmc). in this study, we examined the mechanism by which hne induces autophagy. exposure of rasmc to hne led to the modification of several proteins, most of which were identifie ...201324024137
a quantitative assay to study protein:dna interactions, discover transcriptional regulators of gene expression, and identify novel anti-tumor agents.many dna-binding assays such as electrophoretic mobility shift assays (emsa), chemiluminescent assays, chromatin immunoprecipitation (chip)-based assays, and multiwell-based assays are used to measure transcription factor activity. however, these assays are nonquantitative, lack specificity, may involve the use of radiolabeled oligonucleotides, and may not be adaptable for the screening of inhibitors of dna binding. on the other hand, using a quantitative dna-binding enzyme-linked immunosorbent ...201324022461
[the organization of the projections of the rostromedial tegmental nucleus to the striatum in canine brain].method of retrograde axonal transport of horseradish peroxidase and fluorochromes was used to study the organization of the projections of the rostromedial tegmental nucleus (rmtn) to the functionally diverse regions of striatal structures of dog brain (n=26). it was found that the projection fibers of the neurons of rmtn limbic medial part were directed only to the ventral limbic segments of the nucleus caudatus, the putamen and the nucleus accumbens. however, the convergence of the projection ...201324020179
pka modulates iron trafficking in the striatum via small gtpase, rhes.ras homolog enriched in striatum (rhes), is a highly conserved small guanosine-5'-triphosphate (gtp) binding protein belonging to the ras superfamily. rhes is involved in the dopamine receptor-mediated signaling and behavior though adenylyl cyclase. the striatum-specific gtpase share a close homology with dexras1, which regulates iron trafficking in the neurons when activated though the post-translational modification called s-nitrosylation by nitric oxide (no). we report that rhes physiological ...201323999124
role of mitochondrial permeability transition in human hepatocellular carcinoma hep-g2 cell death induced by rhein.rhein, a compound found as a glucoside in the root of rhubarb, is currently a subject of interest for its antitumor properties. the apoptosis of tumor cell lines induced by rhein was observed, and the involvement of mitochondria was established; however, the role of mitochondrial permeability transition (mpt) remains unknown. here we report that mpt plays an important role in the apoptosis of human hepatocellular carcinoma hep-g2 cells induced by rhein. after adding rhein to the isolated hepatic ...201323994628
de novo galectin-3 expression influences the response of melanoma cells to isatin-schiff base copper (ii) complex-induced oxidative stimulus.galectin-3, a ubiquitous member of the galectin family, has been shown to control cellular proliferation, adhesion, migration and apoptosis; thus, it has a role in tumor development and progression. galectin-3 expression is both up- and down-regulated during melanoma progression. however, conflicting data regarding its roles in tumor biology prompted us to investigate if the presence of galectin-3 influences the response of melanoma cells to a novel metallodrug because metastatic melanoma acquir ...201323994248
enzymatic oxidation of rutin by horseradish peroxidase: kinetic mechanism and identification of a dimeric product by lc-orbitrap mass spectrometry.flavonoid oxidation is important issue in food processing and quality. the kinetic mechanism of enzymatic oxidation of rutin by horseradish peroxidase (hrp) was studied. rutin oxidation reaction was followed by recording of spectral changes over the time at 360 nm. the studied oxidation is mostly enzymatic and less part non-enzymatic. the reaction with hrp has a higher rate compared with the reaction without of hrp, whereby is part of non-enzymatic reaction about 10% of the total reaction. kinet ...201323993605
amperometric biosensor for the determination of histamine in fish samples.a bienzymatic biosensor employing diamine oxidase (dox) and horseradish peroxidase (hrp) for the detection of histamine in fish samples has been developed and optimized in this work. these enzymes have been co-immobilized into a polysulfone/carbon nanotubes/ferrocene membrane by means of phase inversion technique onto screen-printed electrodes. the electrochemical measurements have been carried out in phosphate buffer solution at ph 8.0 in batch mode and low applied potential (-50 mv vs. ag/agcl ...201323993586
a bioassay for lafora disease and laforin glucan phosphatase activity.lafora disease is a rare yet invariably fatal form of progressive neurodegenerative epilepsy resulting from mutations in the phosphatase laforin. several therapeutic options for lafora disease patients are currently being explored, and these therapies would benefit from a biochemical means of assessing functional laforin activity following treatment. to date, only clinical outcomes such as decreases in seizure frequency and severity have been used to indicate success of epilepsy treatment. howev ...201324012855
olfacto-retinalis pathway in austrolebias charrua fishes: a neuronal tracer study.the olfacto-retinal centrifugal system, a constant component of the central nervous system that appears to exist in all vertebrate groups, is part of the terminal nerve (tn) complex. tn allows the integration of different sensory modalities, and its anatomic variability may have functional and evolutionary significance. we propose that the olfacto-retinal branch of tn is an important anatomical link that allows the functional interaction between olfactory and visual systems in austrolebias. by i ...201324012745
competitive immunoassay of progesterone by microchip electrophoresis with chemiluminescence detection.a sensitive and rapid homogeneous immunoassay method based on microchip electrophoresis-chemiluminescence detection (mce-cl) using luminol-hydrogen peroxide as chemiluminescence system catalyzed by horseradish peroxidase (hrp) was developed for the determination of progesterone (p). the assay was based on the competitive immunoreactions between hrp-labeled p antigen (hrp-p) and p with a limited amount of anti-p mouse monoclonal antibody (ab), and mce separation of free hrp-p and hrp-p-ab immunoc ...201324004913
integrated optical microfluidic biosensor using a polycarbazole photodetector for point-of-care detection of hormonal compounds.a picogram-sensitive optical microfluidic biosensor using an integrated polycarbazole photodiode is developed. the photodetector is mainly composed of the blend heterojunction of poly [n-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (pcdtbt) and [6,6]-phenyl c71-butyric acid methyl ester (pc70bm) and the poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (pedot:pss) as the hole transport layer. analyte detection is accomplished via a chemiluminescent i ...201324002194
the influence of angiotensin-(1-7) mas receptor agonist (ave 0991) on mitochondrial proteome in kidneys of apoe knockout mice.excessive action of angiotensin ii on mitochondria has been shown to play an important role in mitochondrial dysfunction, a common feature of atherogenesis and kidney injury. angiotensin-(1-7)/mas receptor axis constitutes a countermeasure to the detrimental effects of angiotensin ii on at1 receptors. the aim of the study was to assess the effects of angiotensin-(1-7) peptidomimetic ave0991 on the kidney mitochondrial proteome in widely used animal model of atherosclerosis (apoe(-/-) mice). prot ...201323988828
spinal interleukin-33 and its receptor st2 contribute to bone cancer-induced pain in mice.cancer pain, particularly bone cancer pain, affects the quality of life of cancer patients, and current treatments are limited. interleukin (il)-33, a new member of the il-1 super family, has been reported to be involved in the modulation of inflammatory pain. however, studies focused on its role in the modulation of cancer pain have been rare. the present study was designed to investigate whether spinal il-33/st2 signaling was involved in bone cancer-induced pain in mice. bone cancer was induce ...201323988433
kinetic rotating droplet electrochemistry: a simple and versatile method for reaction progress kinetic analysis in microliter volumes.here, we demonstrate a new generic, affordable, simple, versatile, sensitive, and easy-to-implement electrochemical kinetic method for monitoring, in real time, the progress of a chemical or biological reaction in a microdrop of a few tens of microliters, with a kinetic time resolution of ca. 1 s. the methodology is based on a fast injection and mixing of a reactant solution (1-10 μl) in a reaction droplet (15-50 μl) rapidly rotated over the surface of a nonmoving working electrode and on the re ...201323985016
introducing novel amorphous carbon nanoparticles as energy acceptors into a chemiluminescence resonance energy transfer immunoassay system.a novel chemiluminescence resonance energy transfer (cret) system for competitive immunoassay of biomolecules was developed by using novel amorphous carbon nanoparticles (cnps) prepared from candle soot as energy acceptors. the cnps were firstly prepared to bind with the antigen (ag) for obtaining the nanocomposite cnp-ag, and this obtained cnp-ag was then reacted with the horseradish peroxidase-labeled antibody (hrp-ab) to assemble the cret system. the luminol catalyzed by hrp serving as the en ...201323979821
social and environmental contexts modulate sleep deprivation-induced c-fos activation in rats.people often sleep deprive themselves voluntarily for social and lifestyle reasons. animals also appear to stay awake longer as a result of their natural curiosity to explore novel environments and interact socially with conspecifics. although multiple arousal systems in the brain are known to act jointly to promote and maintain wakefulness, it remains unclear whether these systems are similarly engaged during voluntary vs. forced wakefulness. using c-fos immunohistochemistry, we compared neuron ...201323973763
calmodulin-dependent regulation of neurotransmitter release differs in subsets of neuronal cells.the purpose of this study was to determine whether calmodulin (cam) plays a role in neurotransmitter release by examining the effect that ophiobolin a (oba), a cam antagonist, on neurotransmitter release from clonal rat pheochromocytoma pc12 cells, primary cortical neurons, and primary cerebellar granule cells. oba inhibited ca²⁺/cam-dependent phosphorylation of camp response element binding protein in all cell types tested. moreover, ca²⁺-dependent release of dopamine and acetylcholine from pc1 ...201323973605
aerobic endurance capacity affects spatial memory and sirt1 is a potent modulator of 8-oxoguanine repair.regular exercise promotes brain function via a wide range of adaptive responses, including the increased expression of antioxidant and oxidative dna damage-repairing systems. accumulation of oxidized dna base lesions and strand breaks is etiologically linked to for example aging processes and age-associated diseases. here we tested whether exercise training has an impact on brain function, extent of neurogenesis, and expression of 8-oxoguanine dna glycosylase-1 (ogg1) and sirt1 (silent mating-ty ...201323973402
chemical, enzymatic and cellular antioxidant activity studies of agaricus blazei murrill.mushrooms possess nutritional and medicinal properties that have long been used for human health preservation and that have been considered by researchers as possible sources of free radical scavengers. in this work, the antioxidant properties of water extracts from agaricus blazei murill, produced by maceration and decoction, are demonstrated in vitro. resistance to oxidation is demonstrated through three mechanisms: i) inhibition of enzymatic oxidative process, with 100% inhibition of hrp (hor ...201323969852
role of calpains in the injury-induced dysfunction and degeneration of the mammalian axon.axonal injury and degeneration, whether primary or secondary, contribute to the morbidity and mortality seen in many acquired and inherited central nervous system (cns) and peripheral nervous system (pns) disorders, such as traumatic brain injury, spinal cord injury, cerebral ischemia, neurodegenerative diseases, and peripheral neuropathies. the calpain family of proteases has been mechanistically linked to the dysfunction and degeneration of axons. while the direct mechanisms by which transecti ...201323969238
cxcl1 contributes to β-amyloid-induced transendothelial migration of monocytes in alzheimer's disease.bone marrow-derived microglia that originates in part from hematopoietic cells, and more particularly from monocytes preferentially attach to amyloid deposition in brains of alzheimer's disease (ad). however, the mechanism of monocytes recruited into the amyloid plaques with an accelerated process in ad is unclear.201323967336
probing horseradish peroxidase catalyzed degradation of azo dye from tannery wastewater.biocatalysis based effluent treatment has outclassed the presently favored physico-chemical treatments due to nil sludge production and monetary savings. azo dyes are commonly employed in the leather industry and pose a great threat to the environment. here, we show the degradation of c. i. acid blue 113 using horseradish peroxidase (hrp) assisted with h2o2 as a co-substrate. it was observed that 0.08 u hrp can degrade 3 ml of 30 mg/l dye up to 80% within 45 min with the assistance of 14 μl of h ...201323961406
superparamagnetic beads for estimation of spinal subarachnoid space permeability in rats.human spinal pathological processes have been linked to a loss of spinal subarachnoid space (ssas) permeability, which has therefore become a target for therapy. hence, it has become important to measure ssas patency in rat models of these human disorders.201323958748
organic cation transporter 2 (slc22a2), a low-affinity and high-capacity choline transporter, is preferentially enriched on synaptic vesicles in cholinergic neurons.organic cation transporters (octs) are expressed mainly in the kidney and liver. octs transport intrinsic organic cations, including monoamine, dopamine, serotonine and choline, across the plasma membrane. here, we demonstrate that oct2 (slc22a2) is expressed in cholinergic neurons, motoneurons in the anterior horn of the spinal cord, and is implicated in acetylcholine (ach) recycling in presynaptic terminals. application of rabbit anti-peptide antibody revealed that oct2 was expressed in the an ...201323958595
flow system for the automatic screening of the effect of phenolic compounds on the luminol-hydrogen peroxide-peroxidase chemiluminescence system.in this work, an automated flow-based procedure for the screening of the effect of the different phenolic compounds on the chemiluminescence (cl) luminol-hydrogen peroxide-horseradish peroxidase (hrp) system is presented. this procedure involves the combination of multisyringe flow injection analysis (mfsia) and sequential injection analysis (sia) techniques and exploits the ability of the different subgroups of phenols, such as cholorophenols, nitrophenols, methylphenols and polyphenols, to enh ...201321308949
trace-level detection of atrazine using immuno-chemiluminescence: dipstick and automated flow injection analyses formats.a sensitive chemiluminescence (cl)-based immunoassay technique based on both dipstick and flow injection analytical formats is reported for the detection of atrazine. in the dipstick-based immunoassay technique, antibody (anti-atrazine) was first immobilized on the nitrocellulose membranes. the dipstick was then treated with atrazine and atrazine-horseradish peroxidase conjugate (atra-hrp) to facilitate the competitive binding. the dipstick was further treated with urea-hydrogen peroxide (u-h202 ...201320334163
[luminol oxidation by hydrogen peroxide with chemiluminescent signal formation catalyzed by peroxygenase from the fungus agrocybe aegerita v.brig].conditions of luminol oxidation by hydrogen peroxide in the presence of peroxygenase from the mushroom agrocybe aegerita v.brig have been optimized. the ph value (8.8) at which fungal peroxygenase produces a maximum chemiluminescent signal has been shown to be similar to the ph optimum value of horseradish peroxidase. luminescence intensity changed when the concentration of tris buffer was varied; maximum intensity of chemiluminescence was observed in 40 mm solution. it has been shown that enhan ...201320198921
[catalytic activity and the stability of horseradish peroxidase increase as a result of its incorporation into a polyelectrolyte complex with chitosan].the incorporation of horseradish peroxidase into polyelectrolyte complexes with chitosans of different molecular weights (mw 5-150 kda) yielded highly active and stable enzyme preparations. as a result of the selection of optimal conditions for the formation of peroxidase-chitosan complexes, it was found that 0.1% chitosan with a mw of 10 kda had the strongest activatory effect on peroxidase (activation degree, > 70%) in the reaction of o-dianisidine oxidation by hydrogen peroxide. the complex f ...201319382699
automated determination of asulam by enhanced chemiluminescence using luminol/peroxidase system.a flow injection system with chemiluminescence detection for the determination of asulam, enhancer of the system luminol-h(2)o(2)-horseradish peroxidase, is proposed. the method shows a moderate selectivity against other pesticides usually present in formulations of herbicides and in water. the procedure was applied to the determination of asulam in tap water samples and a recovery study was carried out in order to validate the method. the obtained results show acceptable recovery values (betwee ...201319544320
catalytic resonance scattering spectral determination of ultratrace horseradish peroxidase using rhodamine s.a highly sensitive and selective resonance scattering spectral assay was proposed for the determination of horseradish peroxidase (hrp), based on its catalytic effect on the h2o2 oxidation of ki to form i3(-). the i3(-) combined respectively with rhodamine (rh) dye such as rhodamine s (rhs), rhodamine 6g (rh6g), rhodamine b (rhb) and butyl-rhodamine b (b-rhb), to form association particles (rh-i3(n). the four rh systems all exhibit a stronger resonance scattering (rs) peak at 424 nm. for the rhs ...201319291809
peroxidase-mediated polymerization of 1-naphthol: impact of solution ph and ionic strength.peroxidase-mediated oxidation has been proposed as a treatment method for naphthol-contaminated water. however, the impact of solution chemistry on naphthol polymerization and removal has not been documented. this research investigated the impact of ph and ionic strength on peroxidase-mediated removal of 1-naphthol in completely mixed batch reactors. the impact of hydrogen peroxide to 1-naphthol ratio and activity of horseradish peroxidase was also studied. size exclusion chromatography was used ...201319704146
spectrofluorimetric determination of vitamin b(1) using horseradish peroxidase as catalyst in the presence of hydrogen peroxide.in this work a new spectrofluorimetric method for the determination of vitamin b(1), based on the catalytic activity of horseradish peroxidase (hrp) in the presence of hydrogen peroxide (h2o2), has been developed. non-fluorescent vitamin b(1) was easily converted through catalytic oxidation in alkaline medium into a fluorescent compound, even without exposure to light. the linear range for vitamin b(1) observed was 0.026-16.83 microg/ml (rsd = 1.75%). the correlation coefficient for the calibrat ...201318780332
a new chemiluminescence paradox: selective inhibition of isoluminol-amplified activity in phagocytes by peptides from annexin ai.chemiluminescence systems enhanced by either isoluminol or luminol in combination with a peroxidase are sensitive methods for the detection of reactive oxygen species (ros) generated by phagocyte nadph oxidase. the two amplifying substrates are structurally very similar, differing only in the position of the amino group in the aromatic ring of the molecules. this difference renders isoluminol a less lipophilic molecule that is less permeable to biological membranes. the use of isoluminol is cons ...201318452130
light-driven horseradish peroxidase cycle by using photo-activated methylene blue as the reducing agent.in this work, the regeneration of native horseradish peroxidase (hrp), following the consecutive reduction of oxo-ferryl pi-cation (compound i) and oxo-ferryl (compound ii) forms, was observed by uv-visible spectrometry and electron paramagnetic resonance (epr) in the presence of methylene (mb+), in the dark and under irradiation. in the dark, mb+ did not affect the rate of hrp compound i and ii reduction, compatible with hydrogen peroxide as the solely reducing species. under irradiation, the d ...201317880521
development of a quantitative bio/chemiluminescence spectrometer determining quantum yields: re-examination of the aqueous luminol chemiluminescence standard.we have developed a bio/chemiluminescence spectrometer with a cooled charge-coupled-device (ccd) detector to obtain a quantitative luminescence spectrum as the absolute number of all emitted photons at each wavelength. the integrated area of the spectrum divided by the number of reacted substrate molecules gives the quantum yield. calibration of the absolute sensitivity of the ccd-spectrometer system was performed by using lasers and a tungsten lamp with calibrated powers as primary light standa ...201317880516
cross-linking of structural proteins in ageing skin: an in situ assay for the detection of amine oxidase activity.with increasing age, dynamic tissues such as lungs, blood vessels and skin lose their ability to both deform and recoil, culminating in tissue stiffening. this loss of tissue elasticity, which profoundly impacts tissue function and thus morbidity, may be due not only to changes in the relative abundance of key extracellular matrix proteins within tissues but also to their accumulation of post-translational modifications. whilst to date attention has focussed primarily on the age-related non-enzy ...201322923173
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