Publications

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amperometric carbohydrate antigen 19-9 immunosensor based on three dimensional ordered macroporous magnetic au film coupling direct electrochemistry of horseradish peroxidase.a sandwich-type electrochemical immunosensor for the detection of carbohydrate antigen 19-9 (ca 19-9) antigen based on the immobilization of primary antibody (ab1) on three dimensional ordered macroporous magnetic (3domm) electrode, and the direct electrochemistry of horseradish peroxidase (hrp) that was used as both the label of secondary antibody (ab2) and the blocking reagent. the 3domm electrode was fabricated by introducing core-shell au-sio2@fe3o4 nanospheres onto the surface of three dime ...201424560371
modification of lysine residues of horseradish peroxidase and its effect on stability and structure of the enzyme.biotechnology is consistently seeking improved enzyme stability. enzymes have great properties, although their marginal stability limits their applications. among the strategies for improving stability of the enzymes, chemical modification is a simple and effective technique. in the present study, chemical modification of horseradish peroxidase (hrp) was carried out with 2,3-dichloromaleic anhydride and 2,3-dimethylmaleic anhydride. hrp is an important heme-containing enzyme. it is widely applie ...201424557950
enhanced chemiluminescence of cdte quantum dots-h₂o₂ by horseradish peroxidase-mimicking dnazyme.in this study, it was found that horseradish peroxidase (hrp)-mimicking dnazyme could effectively enhance the cl emission of cdte quantum dots (qds)-h2o2 system, whereas hrp could not enhance the cl intensity. the cl enhancement mechanism was investigated, and the cl enhancement was supposed to originate from the catalysis of hrp-mimicking dnazyme on the cl reaction between cdte qds and h2o2. meantime, compared with cdte qds-h2o2 cl system, h2o2 concentration was markedly decreased in qds-h2o2-h ...201424556131
small molecule-initiated light-activated semiconducting polymer dots: an integrated nanoplatform for targeted photodynamic therapy and imaging of cancer cells.photodynamic therapy (pdt) is a noninvasive and light-activated method for cancer treatment. two of the vital parameters that govern the efficiency of pdt are the light irradiation to the photosensitizer and visual detection of the selective accumulation of the photosensitizer in malignant cells. herein, we prepared an integrated nanoplatform for targeted pdt and imaging of cancer cells using folic acid and horseradish peroxidase (hrp)-bifunctionalized semiconducting polymer dots (fh-pdots). in ...201424552272
extract from armoracia rusticana and its flavonoid components protect human lymphocytes against oxidative damage induced by hydrogen peroxide.dna damage prevention is an important mechanism involved in cancer prevention by dietary compounds. armoracia rusticana is cultivated mainly for its roots that are used in the human diet as a pungent spice. the roots represent rich sources of biologically active phytocompounds, which are beneficial for humans. in this study we investigated the modulation of h₂o₂ genotoxicity using the a. rusticana root aqueous extract (ae) and two flavonoids (kaempferol or quercetin). human lymphocytes pre-treat ...201424637991
amorphous carbon nanoparticle used as novel resonance energy transfer acceptor for chemiluminescent immunoassay of transferrin.amorphous carbon nanoparticles (acnps) showing highly efficient quenching of chemiluminescence (cl) were prepared from candle soot with a very simple protocol. the prepared acnp was employed as the novel energy acceptor for a chemiluminescence resonance energy transfer (cret)-based immunoassay. in this work, acnp was linked with transferrin (trf), and horseradish peroxidase (hrp) was conjugated to trf antibody (hrp-anti-trf). the immunoreaction rendered the distance between the acnp acceptor and ...201424636417
mechanism of reaction of chlorite with mammalian heme peroxidases.this study demonstrates that heme peroxidases from different superfamilies react differently with chlorite. in contrast to plant peroxidases, like horseradish peroxidase (hrp), the mammalian counterparts myeloperoxidase (mpo) and lactoperoxidase (lpo) are rapidly and irreversibly inactivated by chlorite in the micromolar concentration range. chlorite acts as efficient one-electron donor for compound i and compound ii of mpo and lpo and reacts with the corresponding ferric resting states in a bip ...201424632343
optimization of condition for conjugation of enrofloxacin to enzymes in chemiluminescence enzyme immunoassay.in this study, in order to find out a proper method for conjugation of enrofloxacin to label enzymes, two methods were compared and carbodiimide condensation was proved to be better. the results showed that the binding ratio of enrofloxacin and alkaline phosphatase (alp) was 8:1 and that of enrofloxacin and horseradish peroxidase (hrp) was 5:1. this indicated that conjugate synthesized by carbodiimide condensation was fit for chemiluminescence enzyme immunoassay (cleia). furthermore, data reveal ...201424632155
a novel horseradish peroxidase biosensor towards the detection of dopamine: a voltammetric study.a polymerized film of glycine (gly) was prepared on the surface of carbon paste electrode (cpe) through the cyclic voltammetry (cv) technique. a novel biosensor for the determination of dopamine (da) has been constructed based on horseradish peroxidase (hrp) and multiwalled carbon nanotubes (mwcnts) immobilizing on poly (gly)/cpe through silica sol-gel (sisg) entrapment. cv measurements were employed in order to understand the feasibility of poly (gly) as an electron carrier between the immobili ...201424629262
densified electrochemical sensors based on local redox cycling between vertically separated electrodes in substrate generation/chip collection and extended feedback modes.a new local redox cycling-based electrochemical (lrc-ec) device integrated with many electrochemical sensors has been developed into a small chip device. the lrc-ec chip device was successfully applied for detection of alkaline phosphatase and horseradish peroxidase activity in substrate generation/chip collection (sg/cc) and extended feedback modes, respectively. the new imaging approach with extended feedback mode was particularly effective for sharpening of the image, because this mode uses f ...201424621106
preparation of immobilized l-prolinamide via enzymatic polymerization of phenolic l-prolinamide and evaluation of its catalytic performance for direct asymmetric aldol reaction.phenolic l-prolinamide was allowed to participate in enzymatic polymerization with horseradish peroxidase as the catalyst, generating immobilized l-prolinamide. the catalytic performance of the resultant polymer-supported l-prolinamide for direct asymmetric aldol reaction between aromatic aldehyde and cyclohexanone was studied. the results show that as prepared l-prolinamide can catalyze the aldol reaction at room temperature in the presence of h2o. relevant aldol addition products are obtained ...201424619918
ultrasensitive opto-microfluidic immunosensor integrating gold nanoparticle-enhanced chemiluminescence and highly stable organic photodetector.the expensive fabrication of current opto-microfluidic sensors is a barrier to the successful adoption of these devices in point-of-care testing. this work reports a simple inexpensive opto-microfluidic device incorporating a poly(dimethylsiloxane)-glass hybrid microfluidic chip modified with gold nanoparticles and a high-detectivity, high-stability organic photodetector. the enhancing effect of the gold nanoparticles on horseradish peroxidase-luminol-h2o2 chemiluminescence was exploited in rapi ...201424615640
a fast, sensitive and easy colorimetric assay for chitinase and cellulase activity detection.most of the current colorimetric methods for detection of chitinase or cellulase activities on the insoluble natural polymers chitin and cellulose depend on a chemical redox reaction. the reaction involves the reducing ends of the hydrolytic products. the schales' procedure and the 3,5-dinitrosalicylic acid (dns) method are two examples that are commonly used. however, these methods lack sensitivity and present practical difficulties of usage in high-throughput screening assays as they require b ...201424612932
changes in intestinal glucocorticoid sensitivity in early life shape the risk of epithelial barrier defect in maternal-deprived rats.glucocorticoids (gc) contribute to human intestine ontogeny and accelerate gut barrier development in preparation to birth. rat gut is immature at birth, and high intestinal gc sensitivity during the first two weeks of life resembles that of premature infants. this makes suckling rats a model to investigate postpartum impact of maternal separation (ms)-associated gc release in preterm babies, and whether gc sensitivity may shape ms effects in immature gut. a 4 hours-ms applied once at postnatal ...201424586321
effect of allyl isothiocyanate on ultra-structure and the activities of four enzymes in adult sitophilus zeamais.rarefaction and vacuolization of the mitochondrial matrix of aitc-treated (allyl isothiocyanate-treated) adult sitophilus zeamais were evident according to the ultra-structural by tem. four important enzymes in adult s. zeamais were further studied after fumigation treatment with allyl isothiocyanate (aitc) extracted from armoracia rusticana roots and shoots. the enzymes were glutathione s-transferase (gst), catalase (cat), cytochrome c oxidase, and acetylcholinesterase (ache). the results indic ...201424581380
ion-responsive hemin-g-quadruplexes for switchable dnazyme and enzyme functions.programmed nucleic acid sequences undergo k(+) ion-induced self-assembly into g-quadruplexes and separation of the supramolecular structures by the elimination of k(+) ions by crown ether or cryptand ion-receptors. this process allows the switchable formation and dissociation of the respective g-quadruplexes. the different g-quadruplex structures bind hemin, and the resulting hemin-g-quadruplex structures reveal horseradish peroxidase dnazyme catalytic activities. the following k(+) ion/receptor ...201424683003
the effects of superoxide dismutase mimetic mntmpyp on the altered blood-brain barrier integrity in experimental preeclampsia with or without seizures in rats.we investigated the effects of a cell-permeable superoxide dismutase mimetic, manganese(iii) tetrakis(1-methyl-4-pyridyl)porphyrin (mntmpyp) on blood-brain barrier (bbb) integrity following pentylenetetrazole (ptz)-induced seizures in experimental preeclampsia symptoms induced by n(omega)-nitro-l-arginine methyl ester (l-name) in pregnant rats. to show the functional and morphological alterations in bbb integrity, quantitative analysis of sodium fluorescein (naflu) extravasation, immunohistochem ...201424680906
slow biotransformation of carbon nanotubes by horseradish peroxidase.due to steady increase in use and mass production carbon nanotubes (cnts) will inevitably end up in the environment. because of their chemical nature cnts are expected to be recalcitrant and biotransform only at very slow rates. degradation of cnts within days has recently been reported, but excluding one study, conclusions relied solely on qualitative results. we incubated 13 different types of cnts and subjected them to enzymatic oxidation with horseradish peroxidase and concluded that the ana ...201424678632
western blotting using chemiluminescent substrates.western blotting is a powerful and commonly used tool to identify and quantify a specific protein in a complex mixture (towbin et al., 1979). the technique enables indirect detection of protein samples immobilized on a nitrocellulose or polyvinylidene fluoride (pvdf) membrane.201424674076
expressed glycosylphosphatidylinositol-anchored horseradish peroxidase identifies co-clustering molecules in individual lipid raft domains.lipid rafts that are enriched in glycosylphosphatidylinositol (gpi)-anchored proteins serve as a platform for important biological events. to elucidate the molecular mechanisms of these events, identification of co-clustering molecules in individual raft domains is required. here we describe an approach to this issue using the recently developed method termed enzyme-mediated activation of radical source (emars), by which molecules in the vicinity within 300 nm from horseradish peroxidase (hrp) s ...201424671047
peroxidase gene discovery from the horseradish transcriptome.horseradish peroxidases (hrps) from armoracia rusticana have long been utilized as reporters in various diagnostic assays and histochemical stainings. regardless of their increasing importance in the field of life sciences and suggested uses in medical applications, chemical synthesis and other industrial applications, the hrp isoenzymes, their substrate specificities and enzymatic properties are poorly characterized. due to lacking sequence information of natural isoenzymes and the low levels o ...201424666710
bisretinoid degradation and the ubiquitin-proteasome system.bisretinoid fluorophores of retinal pigment epithelial (rpe) lipofuscin have been shown to undergo degradation in two ways, the first involving photofragmentation following photooxidation of their polyene structure and the second being enzyme-mediated and limited, thus far, to in vitro models employing horseradish peroxidase (hrp). here we show that both of these processes impact the ubiquitin-proteasome system (ups) of the rpe cell. by measuring the consumption of a2e and all-trans-retinal dime ...201424664748
in vivo effects of 17β-estradiol on cardiac na(+)/k(+)-atpase expression and activity in rat heart.in this study the in vivo effects of estradiol in regulating na(+)/k(+)-atpase function in rat heart was studied. adult male wistar rats were treated with estradiol (40μg/kg, i.p.) and after 24h the animals were sacrificed and the heart excised. following estradiol administration, cardiac na(+)/k(+)-atpase activity, expression of the α1 subunit, and phosphorylation of the α1 subunit were significantly increased. these animals also had significantly decreased levels of digoxin-like immunoreactive ...201424662727
all-water-based electron-beam lithography using silk as a resist.traditional nanofabrication techniques often require complex lithographic steps and the use of toxic chemicals. to move from the laboratory scale to large scales, nanofabrication should be carried out using alternative procedures that are simple, inexpensive and use non-toxic solvents. recent efforts have focused on nanoimprinting and the use of organic resists (such as quantum dot-polymer hybrids, dna and poly(ethylene glycol)), which still require, for the most part, noxious chemicals for proc ...201424658173
hemoprotein-based supramolecular assembling systems.hemoproteins are metalloproteins which include iron porphyrin as a cofactor. these proteins have received much attention as promising building blocks for development of new types of biomaterials. this review summarizes recent efforts in the rational design of supramolecular hemoprotein assemblies using myoglobin, horseradish peroxidase, cytochrome b562 and cytochrome c as a monomer unit. the processes of coordination bond-mediated assembly or domain swapping-mediated assembly provide defined oli ...201424658057
homogeneous assay of target molecules based on chemiluminescence resonance energy transfer (cret) using dnazyme-linked aptamers.we have designed a single-stranded dnazyme-aptamer sensor for homogeneous target molecular detection based on chemiluminescence resonance energy transfer (cret). the structure of the engineered single-stranded dna (ssdna) includes the horseradish peroxidase (hrp)-like dnazyme, optimum-length linker (10-mer-length dna), and target-specific aptamer sequences. a quencher dye was modified at the 3' end of the aptamer sequence. the incorporation of hemin into the g-quadruplex structure of dnazyme yie ...201424658027
development of enzyme-linked immunosorbent assay for estimation of urinary albumin.yearly estimation of urinary albumin is a prerequisite for predicting renal status in diabetes type ii patients with negative dipstick results for overt proteinuria. a simple, sensitive, and cost-effective enzyme linked immunosorbent assay (elisa) for urinary albumin has been developed using human serum albumin antiserum (hsa-antiserum), hsa-biotin, and streptavidin-horseradish peroxidase (sa-hrp) conjugates. to the antibody-coated wells, 100 μl of hsa standards followed by 1:100 diluted urine s ...201424654825
thin-layer polymer wrapped enzymes encapsulated in hierarchically mesoporous silica with high activity and enhanced stability.a novel soft-hard cooperative approach was developed to synthesize bioactive mesoporous composite by pre-wrapping penicillin g amidase with poly(acrylaimde) nanogel skin and subsequently incorporating such penicillin g amidase nanocapsules into hierarchically mesoporous silica. the as-received bioactive mesoporous composite exhibited comparable activity and extraordinarily high stability in comparison with native penicillin g amidase and could be used repetitively in the water-medium hydrolysis ...201424651701
expression of human apolipoprotein e4 reduces insulin-receptor substrate 1 expression and akt phosphorylation in the ageing liver.the diabetic drug rosiglitazone was reported to improve glucose tolerance in insulin-resistant apoe3 but not apoe4 knock-in mice. we therefore examined whether apolipoprotein e (apoe) has genotype-specific effects on liver insulin function. at 12 weeks, no difference in liver insulin signaling was detected between fasting apoe3 and apoe4 mice. at 72 weeks however, apoe4 mice had lower irs-1 and pi3k expression, and reduced akt phosphorylation. this decline was associated with lower insulin and h ...201424649407
ursolic acid, a natural pentacyclic triterpenoid, inhibits intracellular trafficking of proteins and induces accumulation of intercellular adhesion molecule-1 linked to high-mannose-type glycans in the endoplasmic reticulum.ursolic acid (3β-hydroxy-urs-12-en-28-oic acid) is a natural pentacyclic triterpenoid that is present in many plants, including medicinal herbs, and foods. ursolic acid was initially identified as an inhibitor of the expression of intercellular adhesion molecule-1 (icam-1) in response to interleukin-1α (il-1α). we report here a novel biological activity: ursolic acid inhibits intracellular trafficking of proteins. ursolic acid markedly inhibited the il-1α-induced cell-surface icam-1 expression i ...201424649404
supramolecular assemblies of nucleoside functionalized carbon nanotubes: synthesis, film preparation, and properties.nucleoside-functionalized multi-walled carbon nanotubes (n-mwcnts) were synthesized and characterized. a self-organization process using hydrogen bonding interactions was then used for the fabrication of self-assembled n-mwcnts films free of stabilizing agents, polymers, or surfactants. membranes were produced by using a simple water-dispersion-based vacuum-filtration method. hydrogen-bond recognition was confirmed by analysis with ir spectroscopy and tem images. restoration of the electronic co ...201424648250
a dna origami nanorobot controlled by nucleic acid hybridization.a prototype for a dna origami nanorobot is designed, produced, and tested. the cylindrical nanorobot (diameter of 14 nm and length of 48 nm) with a switchable flap, is able to respond to an external stimulus and reacts by a physical switch from a disarmed to an armed configuration able to deliver a cellular compatible message. in the tested design the robot weapon is a nucleic acid fully contained in the inner of the tube and linked to a single point of the internal face of the flap. upon actuat ...201424648163
[irreversible chemical afm-fishing for the detection of low-copied proteins].the atomic-force microscopy-based method of irreversible chemical afm-fishing (afm-if(ch)) has been developed for the detection of proteins at ultra-low concentrations in solution. using this method, a very low concentration of horseradish peroxidase (hrp) protein (10(-17) m) was detected in solution. a theoretical model that allows the description of obtained experimental data, is proposed. this model takes into consideration both the transport of the protein from the bulk solution onto the afm ...201424749246
rapid screening of multiple antibiotic residues in milk using disposable amperometric magnetosensors.disposable amperometric magnetosensors, involving a mixture of modified-magnetic beads (mbs), for the multiplex screening of cephalosporins (cphs), sulfonamides (sas) and tetracyclines (tcs) antibiotic residues in milk are reported for the first time in this work. the multiplexed detection relies on the use of a mixture of target specific modified magnetic beads (mbs) and application of direct competitive assays using horseradish peroxidase (hrp)-labeled tracers. the amperometric responses measu ...201424745735
purification and characterization of novel cationic peroxidases from asparagus acutifolius l. with biotechnological applications.four novel basic peroxidases, named aap-1, aap-2, aap-3, and aap-4, were purified from asparagus acutifolius l. seeds by cation-exchange and gel filtration chromatographies. the four proteins showed a similar electrophoretic mobility of 46 kda while, by maldi-tof ms, different mr values of 42758.3, 41586.9, 42796.3, and 41595.5 were determined for aap-1, aap-2, aap-3, and aap-4, respectively. n-terminal sequences of aaps 1-4 up to residue 20 showed a high percentage of identity with the peroxida ...201424740695
macro/nano-gel composite as an injectable and bioactive bulking material for the treatment of urinary incontinence.many women around the world are suffering from urinary incontinence, defined as the unintentional leakage of urine by external abnormal pressure. although various kinds of materials have been utilized to treat this disease, therapies that are more effective are still needed for the treatment of urinary incontinence. here, we present a macro/nanogel composed of in situ forming gelatin-based macrogels and self-assembled heparin-based nanogels, which can serve as an injectable and bioactive bulking ...201424739122
whisker-related circuitry in the trigeminal nucleus principalis: ultrastructure.trigeminal (v) nucleus principalis (prv) is the requisite brainstem nucleus in the whisker-to-barrel cortex model system that is widely used to reveal mechanisms of map formation and information processing. yet, little is known of the actual prv circuitry. in the ventral "barrelette" portion of the adult mouse prv, relationships between v primary afferent terminals, thalamic-projecting prv neurons, and gamma-aminobutyric acid (gaba)-ergic terminals were analyzed in the electron microscope. prima ...201424738912
simultaneous electropolymerization and electro-click functionalization for highly versatile surface platforms.simple preparation methods of chemically versatile and highly functionalizable surfaces remain rare and present a challenging research objective. here, we demonstrate a simultaneous electropolymerization and electro-click functionalization process (seec) for one-pot self-construction of aniline- and naphthalene-based functional polymer films where both polymerization and click functionalization are triggered by applying electrochemical stimuli. cyclic voltammetry (cv) can be applied for the simu ...201424738664
synergy-based small-molecule screen using a human lung epithelial cell line yields δf508-cftr correctors that augment vx-809 maximal efficacy.the most prevalent cystic fibrosis transmembrane conductance regulator (cftr) mutation causing cystic fibrosis, δf508, impairs folding of nucleotide binding domain (nbd) 1 and stability of the interface between nbd1 and the membrane-spanning domains. the interfacial stability defect can be partially corrected by the investigational drug vx-809 (3-[6-[[[1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl]amino]-3-methyl-2-pyridinyl]-benzoic acid) or the r1070w mutation. second-generation δf ...201424737137
evaluation of inferior alveolar nerve regeneration by bifocal distraction osteogenesis with retrograde transportation of horseradish peroxidase in dogs.bifocal distraction osteogenesis has been shown to be a reliable method for reconstructing segmental mandibular defects. however, there are few reports regarding the occurrence of inferior alveolar nerve regeneration during the process of distraction. previously, we reported inferior alveolar nerve regeneration after distraction, and evaluated the regenerated nerve using histological and electrophysiological methods. in the present study, we investigated axons regenerated by bifocal distraction ...201424732938
a rapid immunomagnetic beads-based immunoassay for the detection of β-casein in bovine milk.an immunomagnetic beads-based enzyme-linked immunosorbent assay (imbs-elisa) was developed for the detection of β-casein in bovine milk. immunomagnetic beads (imbs) were employed as the solid phase. the anti-β-casein monoclonal antibody (mcab) bound to imbs was used as capture probe and an anti-β-casein polyclonal antibody (pcab), labelled with horseradish peroxidase (hrp), was employed as detector probe. three reaction and two washing steps were needed. each reaction needed 10 min or less, whic ...201424731368
development of ultrasensitive direct chemiluminescent enzyme immunoassay for determination of aflatoxin m1 in milk.a direct competitive chemiluminescent enzyme-linked immunosorbent assay (cl-elisa) for detecting aflatoxin m1 (afm1) was developed. to improve the sensitivity of the assay, a mixture of 3-(10'-phenothiazinyl)-propane-1-sulfonate (sptz) and 4-morpholinopyridine (morph) was used to enhance peroxidase-induced cl. the concentrations of the coating anti-afm1 antibody and the conjugate of afb1 with horseradish peroxidase the conditions of the chemiluminescent assay were varied to optimise the conditio ...201424731347
highly sensitive microfluidic competitive enzyme immunoassay based on chemiluminescence resonance energy transfer for the detection of neuron-specific enolase.a microfluidic competitive enzyme immunoassay based on chemiluminescence resonance energy transfer (cret) was developed for highly sensitive detection of neuron-specific enolase (nse). the cret system consisted of horseradish peroxidase (hrp)/luminol as a light donor and fluorescein isothiocyanate as an acceptor. when fluorescein isothiocyanate-labeled antibody binds with hrp-labeled antigen to form immunocomplex, the donor and acceptor are brought close each other and cret occurs in the immunoc ...201424723253
enzyme-based inverse opals: a facile and promising platform for fabrication of biocatalysts.a facile and promising approach was developed to fabricate enzyme-based 3d-ordered macroporous biocatalysts (enzyme-based inverse opals) by using the colloidal crystal templating method. horseradish peroxidase- and amylase-based inverse opals were prepared, which verified that this method is suitable for various enzymes.201424722982
an optical sensor for pesticide determination based on the autoindicating optical properties of peroxidase.during the enzymatic reaction of the heme-protein horseradish peroxidase (hrp) with hydrogen peroxide there are changes in the molecular absorption spectra of hrp and its different oxidation states which can be used for quantitative determination of the substrate. one of these intermediate oxidation states is the hrpii, with iron as an oxyferryl. this compound is assumed to be responsible for the organophosphate pesticide degradation in the fenton reaction. in this work, the enzymatic hrp-h₂o₂ r ...201424720992
electrochemical immunosensor based on hydrophilic polydopamine-coated prussian blue-mesoporous carbon for the rapid screening of 3-bromobiphenyl.a sensitive electrochemical immunosensor for 3-bromobiphenyl (3-bbp) detection was constructed by employing a new polydopamine coated prussian blue-mesoporous carbon (pdop/pb/cmk-3) nanocomposite as the substrate platform and multi-horseradish peroxidase-double helix carbon nanotubes-secondary antibody (multi-hrp-dhcnts-ab2) as the signal label. pb/cmk-3 was firstly successfully in-situ synthesized with the aid of the cmk-3 reduction, which was characterized by transmission electron microscope ( ...201424709325
central pupillary light reflex circuits in the cat: i. the olivary pretectal nucleus.the central pathways subserving the feline pupillary light reflex were examined by defining retinal input to the olivary pretectal nucleus (opt), the midbrain projections of this nucleus, and the premotor neurons within it. unilateral intravitreal wheat germ agglutinin-conjugated horseradish peroxidase (wga-hrp) injections revealed differences in the pattern of retinal opt termination on the two sides. injections of wga-hrp into opt labeled terminals bilaterally in the anteromedian nucleus, and ...201424706328
mechanism and regulation of peroxidase-catalyzed nitric oxide consumption in physiological fluids: critical protective actions of ascorbate and thiocyanate.catalytic consumption of nitric oxide (no) by myeloperoxidase and related peroxidases is implicated as playing a key role in impairing no bioavailability during inflammatory conditions. however, there are major gaps in our understanding of how peroxidases consume no in physiological fluids, in which multiple reactive enzyme substrates and antioxidants are present. notably, ascorbate has been proposed to enhance myeloperoxidase-catalyzed no consumption by forming no-consuming substrate radicals. ...201424704973
dna sensors and aptasensors based on the hemin/g-quadruplex-controlled aggregation of au nps in the presence of l-cysteine.l-cysteine induces the aggregation of au nanoparticles (nps), resulting in a color transition from red to blue due to interparticle plasmonic coupling in the aggregated structure. the hemin/g-quadruplex horseradish peroxidase-mimicking dnazyme catalyzes the aerobic oxidation of l-cysteine to cystine, a process that inhibits the aggregation of the nps. the degree of inhibition of the aggregation process is controlled by the concentration of the dnazyme in the system. these functions are implement ...201424700798
enzyme encapsulated hollow silica nanospheres for intracellular biocatalysis.hollow silica nanospheres (hsn) with low densities, large interior spaces and permeable silica shells are suitable for loading enzymes in the cavity to carry out intracellular biocatalysis. the porous shell can protect the encapsulated enzymes against proteolysis and attenuate immunological response. we developed a microemulsion-templating method for confining horseradish peroxidase (hrp) in the cavity of hsn. this simple one-pot enzyme encapsulation method allows entrapping of the enzyme, which ...201424694065
hierarchical hybrid peroxidase catalysts for remediation of phenol wastewater.we report a new family of hierarchical hybrid catalysts comprised of horseradish peroxidase (hrp)-magnetic nanoparticles for advanced oxidation processes and demonstrate their utility in the removal of phenol from water. the immobilized hrp catalyzes the oxidation of phenols in the presence of h2 o2 , producing free radicals. the phenoxy radicals react with each other in a non-enzymatic process to form polymers, which can be removed by precipitation with salts or condensation. the hybrid peroxid ...201424692298
sensitive electrochemical aptamer biosensor for dynamic cell surface n-glycan evaluation featuring multivalent recognition and signal amplification on a dendrimer-graphene electrode interface.we demonstrate a multivalent recognition and highly selective aptamer signal amplification strategy for electrochemical cytosensing and dynamic cell surface n-glycan expression evaluation by the combination of concanavalin a (con a), a mannose binding protein, as a model, conjugated poly(amidoamine) dendrimer on a chemically reduced graphene oxide (rgo-den) interface, and aptamer- and horseradish peroxidase-modified gold nanoparticles (hrp-aptamer-aunps) as nanoprobes. in this strategy, the rgo- ...201424684138
expression of maspin in benign and malignant salivary gland tumors: an immunohistochemical study.maspin is a novel serine protease inhibitor (serpin) with multifaceted tumor-suppressive activities. it was originally identified in normal human breast myoepithelial cells and shows variable expression in different types of cancer cells. maspin displays anti-metastatic properties in mammary and prostate cancer. its expression is maintained during ovarian, lung and pancreatic carcinogenesis, indicating that maspin regulated metastatic potential is tissue specific. thus, it is possible that maspi ...201425098993
fe-taml encapsulated inside mesoporous silica nanoparticles as peroxidase mimic: femtomolar protein detection.peroxidase, such as horseradish peroxidase (hrp), conjugated to antibodies are routinely used for the detection of proteins via an elisa type assay in which a critical step is the catalytic signal amplification by the enzyme to generate a detectable signal. synthesis of functional mimics of peroxidase enzyme that display catalytic activity which far exceeds the native enzyme is extremely important for the precise and accurate determination of very low quantities of proteins (fm and lower) that i ...201425089579
tyramine-based enzymatic conjugate repeats for ultrasensitive immunoassay accompanying tyramine signal amplification with enzymatic biocatalytic precipitation.a new impedimetric immunoassay protocol based on enzyme-triggered formation of tyramine-enzyme repeats on gold nanoparticle (aunp) was designed for highly sensitive detection of carcinoembryonic antigen (cea, as a model) by virtue of utilizing enzymatic biocatalytic precipitation toward 4-chloro-1-naphthol (4-cn) on anti-cea antibody (ab1)-modified immunosensor. initially, aunp was functionalized with horseradish peroxidase and detection antibody (hrp-aunp-ab2), and then hrp-tyramine conjugate w ...201425088522
excited singlet molecular o₂(¹δg) is generated enzymatically from excited carbonyls in the dark.in mammalian tissues, ultraweak chemiluminescence arising from biomolecule oxidation has been attributed to the radiative deactivation of singlet molecular oxygen [o2 ((1)δg)] and electronically excited triplet carbonyl products involving dioxetane intermediates. herein, we describe evidence of the generation of o2 ((1)δg) in aqueous solution via energy transfer from excited triplet acetone. this involves thermolysis of 3,3,4,4-tetramethyl-1,2-dioxetane, a chemical source, and horseradish peroxi ...201425087485
poly(neutral red) based hydrogen peroxide biosensor for chromium determination by inhibition measurements.amperometric hydrogen peroxide enzyme inhibition biosensors based on horseradish peroxidase (hrp) immobilised on electropolymerised neutral red (nr) or directly on the surface of carbon film electrodes (cfe) have been successfully applied to the determination of toxic cr(iii) and cr(vi). parameters influencing the performance of the biosensor including the enzyme immobilisation method, the amount of hydrogen peroxide, applied potential and electrolyte ph were optimised. the inhibition of horsera ...201425080156
π-conjugated carbon radicals at graphene oxide to initiate ultrastrong chemiluminescence.graphene oxide has widely been employed in various fields, but its structure and composition has still not been fully understood. here we report that freshly prepared graphene oxide exhibits a large number of π-conjugated carbon radicals at its π-network plane, which result from the addition reaction of hydroxyl radicals from h2o2 onto the conjugated double bonds of graphene oxide. the π-conjugated carbon radicals can directly initiate the long-lasting visible chemiluminescence of luminol, which ...201425078281
detecting the oxidative reactivity of nanoparticles: a new protocol for reducing artifacts.understanding the oxidative reactivity of nanoparticles (nps; <100 nm) could substantially contribute to explaining their toxicity. we attempted to refine the use of 2'7-dichlorodihydrofluorescein (dcfh) to characterize np generation of reactive oxygen species (ros). several fluorescent probes have been applied to testing oxidative reactivity, but despite dcfh being one of the most popular for the detection of ros, when it has been applied to nps there have been an unexplainably wide variability ...201425076842
hydrogen peroxide-independent generation of superoxide by plant peroxidase: hypotheses and supportive data employing ferrous ion as a model stimulus.when plants are threaten by microbial attacks or treated with elicitors, alkalization of extracellular space is often induced and thus ph-dependent extracellular peroxidase-mediated oxidative burst reportedly takes place, especially at the site of microbial challenge. however, direct stimulus involved in activation of peroxidase-catalyzed oxidative burst has not been identified to date. here, we would like to propose a likely role for free ferrous ion in reduction of ferric native peroxidase int ...201425071789
highly sensitive multianalyte immunochromatographic test strip for rapid chemiluminescent detection of ractopamine and salbutamol.a novel immunochromatographic assay (ica) was proposed for rapid and multiple assay of β2-agonists, by utilizing ractopamine (rac) and salbutamol (sal) as the models. owing to the introduction of chemiluminescent (cl) approach, the proposed protocol shows much higher sensitivity. in this work, the described ica was based on a competitive format, and horseradish peroxidase-tagged antibodies were used as highly sensitive cl probes. quantitative analysis of β2-agonists was achieved by recording the ...201425066723
nerve growth factor promotes expression of novel genes in intervertebral disc cells that regulate tissue degradation: laboratory investigation.increased neurotrophin activity in degenerative intervertebral discs (ivds) is one potential cause of chronic low-back pain (lbp). the aim of the study was to assess if nerve growth factor (ngf) might alter gene expression of ivd cells and contribute to disc degeneration by enhancing expression or activity of factors that cause breakdown of ivd matrix.201425062286
glucosinolate profile and distribution among plant tissues and phenological stages of field-grown horseradish.profile and distribution of glucosinolates (gls) were detected in plant tissues of horseradish at different developmental stages: beginning of vegetative re-growth, flowering and silique formation. the gls profile varied widely in the different tissues: we identified 17 gls in roots and sprouts, one of which was not previously characterized in horseradish, i.e. the 2(s)-hydroxy-2-phenylethyl-gls (glucobarbarin) and/or 2(r)-hydroxy-2-phenylethyl-gls (epiglucobarbarin), 11 already found in the roo ...201425060759
g-quadruplex dna biosensor for sensitive visible detection of genetically modified food.in this paper, a novel label-free g-quadruplex dnazyme sensor has been proposed for colorimetric identification of gmo using camv 35s promoter sequence as the target. the binary probes can fold into g-quadruplex structure in the presence of dna-t (target dna) and then combine with hemin to form a dnazyme resembling horseradish peroxidase. the detection system consists of two g-rich probes with 2:2 split mode by using the absorbance and color of abts(2-) as signal reporter. upon the addition of a ...201425059184
roles of horseradish peroxidase in response to terbium stress.the pollution of the environment by rare earth elements (rees) causes deleterious effects on plants. peroxidase plays important roles in plant response to various environmental stresses. here, to further understand the overall roles of peroxidase in response to ree stress, the effects of the ree terbium ion (tb(3+)) on the peroxidase activity and h2o2 and lignin contents in the leaves and roots of horseradish during different growth stages were simultaneously investigated. the results showed tha ...201425055927
investigation of processes in black tea manufacture through model fermentation (oxidation) experiments.flavanol depleted whole fresh green tea leaf powder, as reported in the literature, was used as matrix for a systematic study of the endogenous oxidative enzymatic conversion of selected flavanol combinations to theaflavins and thearubigins. the activity of the two crucial enzymes polyphenol oxidase (ppo) and peroxidase (pod) was controlled individually through addition of h2o2 and/or o2. using the endogenous peroxidase only it was shown that (-)-epicatechin alone did not react with pod. accordi ...201425051300
electron paramagnetic resonance and electron-nuclear double resonance studies of the reactions of cryogenerated hydroperoxoferric-hemoprotein intermediates.the fleeting ferric peroxo and hydroperoxo intermediates of dioxygen activation by hemoproteins can be readily trapped and characterized during cryoradiolytic reduction of ferrous hemoprotein-o2 complexes at 77 k. previous cryoannealing studies suggested that the relaxation of cryogenerated hydroperoxoferric intermediates of myoglobin (mb), hemoglobin, and horseradish peroxidase (hrp), either trapped directly at 77 k or generated by cryoannealing of a trapped peroxo-ferric state, proceeds throug ...201425046203
reversible chemical tuning of charge carriers for enhanced photoelectrochemical conversion and probing of living cells.a facile, solution method for reversible tuning of oxygen vacancies inside tio2 nanowires, in which the reducing treatment of tio2 by nabh4 leads to 2.4-fold increase of photocurrent density, compared to pristine tio2 nanowires, is reported. subsequent oxidizing treatment using kmno4 or annealing in air can reset the photocurrent density to the original values. the incident photo-to-current conversion efficiency measurement exhibits that the reduced tio2 nanowires present both enhanced photoacti ...201425044916
cell-free identification of novel n-myristoylated proteins from complementary dna resources using bioorthogonal myristic acid analogues.to establish a non-radioactive, cell-free detection system for protein n-myristoylation, metabolic labeling in a cell-free protein synthesis system using bioorthogonal myristic acid analogues was performed. after cu(i)-catalyzed azide-alkyne cycloaddition (cuaac) with a biotin tag, the tagged proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) and blotted on a polyvinylidene fluoride (pvdf) membrane, and then protein n-myristoylation was detected by en ...201425043870
click synthesis of glucose-functionalized hydrophilic magnetic mesoporous nanoparticles for highly selective enrichment of glycopeptides and glycans.selective enrichment of glycopeptides from complex biological samples is essential for ms-based glycoproteomics, but challenges still remain. in this work, glucose-functionalized magnetic mesoporous nanoparticles (mmns), which hold the attractive features of well-defined core/shell structure, high specific surface area (324m(2)/g), narrow pore size distribution (2.2nm) and high magnetic responsivity (69.1emug(-1)), were synthesized via click chemistry and applied to enrich glycopeptides and glyc ...201425042437
effect of local application of transforming growth factor-β at the nerve repair site following chronic axotomy and denervation on the expression of regeneration-associated genes. laboratory investigation.although peripheral nerves can regenerate after traumatic injury, functional recovery is often suboptimal, especially after injuries to large nerve trunks such as the sciatic nerve or brachial plexus. current research with animal models suggests that the lack of functional recovery resides in the lack of sufficient mature axons reaching their targets due to the loss of neurotrophic support by schwann cells in the distal stump of injured nerves. this study was designed to investigate the effect o ...201425036208
naturally-occurring tetrahydro-β-carboline alkaloids derived from tryptophan are oxidized to bioactive β-carboline alkaloids by heme peroxidases.β-carbolines are indole alkaloids that occur in plants, foods, and endogenously in mammals and humans, and which exhibit potent biological, psychopharmacological and toxicological activities. they form from naturally-occurring tetrahydro-β-carboline alkaloids arising from tryptophan by still unknown way and mechanism. results in this research show that heme peroxidases catalyzed the oxidation of tetrahydro-β-carbolines (i.e. 1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid and 1-methyl-1,2,3,4-t ...201425035927
synthesis of hierarchical iron hydrogen phosphate crystal as a robust peroxidase mimic for stable h₂o₂ detection.to develop a green, cost-efficient and robust peroxidase mimic, micro/nano hierarchical morphology (for ease of separation and reuse), relative chemically stable composition (for ease of storage) and stable crystal structure (for long-term stability) are highly desired. herein, using phosphoric acid as a chelating ligand to control the release of iron ions, hierarchical iron(iii) hydrogen phosphate hydrate crystals are successfully prepared by nanosheets formation and following self-assembling i ...201425029358
single-molecule enzymatic conformational dynamics: spilling out the product molecules.product releasing is an essential step of an enzymatic reaction, and a mechanistic understanding primarily depends on the active-site conformational changes and molecular interactions that are involved in this step of the enzymatic reaction. here we report our work on the enzymatic product releasing dynamics and mechanism of an enzyme, horseradish peroxidase (hrp), using combined single-molecule time-resolved fluorescence intensity, anisotropy, and lifetime measurements. our results have shown a ...201425025461
food allergens are transferred intact across the rat blood-placental barrier in vivo.we investigated the mechanism of transplacental macromolecular transport in rats on the nineteenth day of pregnancy using tracers, transmission electron microscopy and immunohistochemistry. the blood-placental barrier of full-term rat placentas was composed of a trilaminar layer of trophoblast cells that separates the fetal capillaries from the maternal blood spaces: a layer of cytotrophoblasts lining the maternal blood space and a bilayer of syncytiotrophoblast surrounding the fetal capillaries ...201423475277
sex differences in the number and size of motoneurons innervating rat medial gastrocnemius muscle.the sex differences in the number and morphometric parameters of motoneurons in motor nuclei are poorly known. the aim of this study was to determine the differences in the number and size of alpha and gamma motoneurons of the medial gastrocnemius (mg) muscle in male and female wistar rats. retrogradely labelled cell bodies of motoneurons of 6 months old animals were studied following a bath of the proximal stump of the transected mg nerve in a horseradish peroxidase solution. the number and som ...201423617786
evaluation of lophine derivatives as l-012 (luminol analog)-dependent chemiluminescence enhancers for measuring horseradish peroxidase and h2o2.8-amino-5-chloro-7-phenylpyrido[3,4-d]pyridazine-1,4(2h,3h)dione (l-012) was recently synthesized as a new chemiluminescence (cl) probe; the light intensity and the sensitivity of l-012 are higher than those of other cl probes such as luminol. previously, our group developed four lophine-based cl enhancers of the horseradish peroxidase (hrp)-catalyzed cl oxidation of luminol, namely 2-(4-hydroxyphenyl)-4,5-diphenylimidazole (hdi), 2-(4-hydroxyphenyl)-4,5-di(2-pyridyl)imidazole (hpi), 4-(4,5-diph ...201423630098
detection of superoxide anion and hydrogen peroxide production by cellular nadph oxidases.the recent recognition that isoforms of the cellular nadph-dependent oxidases, collectively known as the nox protein family, participate in a wide range of physiologic and pathophysiologic processes in both the animal and plant kingdoms has stimulated interest in the identification, localization, and quantitation of their products in biological settings. although several tools for measuring oxidants released extracellularly are available, the specificity and selectivity of the methods for reliab ...201423660153
regeneration of facial nerve defects with xenogeneic acellular nerve grafts in a rat model.because of ease of harvest and low immunogenicity, xenogeneic acellular nerve graft (xang) may be an alternative to autologous nerve to repair facial nerve defects.201423729307
ultrastructure and synaptic connectivity of main and accessory olfactory bulb efferent projections terminating in the rat anterior piriform cortex and medial amygdala.neurons in the main olfactory bulb relay peripheral odorant signals to the anterior piriform cortex (apir), whereas neurons of the accessory olfactory bulb relay pheromone signals to the medial amygdala (mea), suggesting that they belong to two functionally distinct systems. to help understand how odorant and pheromone signals are further processed in the brain, we investigated the synaptic connectivity of identified axon terminals of these neurons in layer ia of the apir and posterodorsal part ...201423756876
horseradish peroxidase-mediated encapsulation of mammalian cells in hydrogel particles by dropping.we report a method for preparation of mammalian cell-enclosing hydrogel particles through horseradish peroxidase (hrp)-catalysed hydrogelation by dropping cell-suspending aqueous solution into an aqueous coagulation solution. an aqueous solution of 10% (w/v) gelatin derivative possessing phenolic hydroxyl (ph) moieties (gelatin-ph), hepg2 cells and 10 u/ml hrp was dropped into an aqueous coagulation solution containing 1 mm h2o2. the resultant hydrogel formed through the hrp-catalysed reaction c ...201423862725
development of a highly sensitive chemiluminescence enzyme immunoassay using enhanced luminol as substrate.in this study, a high sensitivity chemiluminescence enzyme immunoassay (cleia) based on novel enhancers was developed. under optimal conditions, we developed an enhanced chemiluminescence reaction (ecr) catalyzed by horseradish peroxidase (hrp-c) in the presence of 3-(10'-phenothiazinyl) propane-1-sulfonate (sptz) and 4-morpholinopyridine (morp) as enhancers. the limit of detection of the newly prepared chemiluminescent cocktail for hrp was 0.33 pg/well, which is lower than that of commercial su ...201423785024
minimal oxidation and inflammogenicity of pristine graphene with residence in the lung.two-dimensional graphitic carbon, graphene, is a new form of nanomaterial with great potential in a wide variety of applications. it is therefore crucial to investigate the behaviour of graphene in biological systems to assess potential adverse effects that might follow from inhalation exposure. in this study we focussed on medium-term effects of graphene in lung tissue by investigating the pulmonary inflammation 6 weeks after pharyngeal aspiration of unoxidised multilayered graphene platelets ( ...201423924429
a novel method to directionally stabilize enzymes together with redox mediators by electrodeposition.this paper depicts a novel method to directionally stabilize enzymes together with redox mediators by electrodeposition. chitosan was used as a stabilizing matrix. by electrochemical removal of local h(+), chitosan close to working electrode became locally insoluble, and enzymes and redox mediators in chitosan were stabilized. the microelectrode on home-made microelectrode array (mea) served as the working electrode. three model enzymes--horseradish peroxidase (hrp), glucose oxidase (god), and g ...201423974156
effect of aqueous extract of cigarette smoke on peripheral blood polymorphonuclear leukocytes chemiluminescence.cigarette smoke induces a vast cohort of deleterious effects on biological structures. in the present paper, the effect of aqueous extract of cigarette smoke on the activity of polymorphonuclear leukocytes was studied. although the aqueous extract of cigarette smoke inhibits the luminol oxidation catalysed by horseradish peroxidase, it strongly interacts with polymorphonuclear leukocytes and inhibits their phorbol-induced chemiluminescence in the presence of either luminol or lucigenin. the resu ...201410862145
ph-dependent one- and two-electron oxidation of 3,5-dicarbethoxy-2,6-dimethyl-4-ethyl-1,4-dihydropyridine catalyzed by horseradish peroxidase.the porphyrinogenic agent 3,5-dicarbethoxy-2,6-dimethyl-4-ethyl-1,4-dihydropyridine (ddep) is known to inactivate hepatic cytochrome p450 (p450) enzymes 2c11, 2c6, and 3a1 [correia et al. (1987) arch. biochem. biophys. 258, 436-451] by different mechanisms. the inactivation of p450 2c11 and 2c6 appears to be due to the ethylation of the heme in the active sites of the enzymes [augusto et al. (1982) j. biol. chem. 257, 11288-11295], whereas the inactivation of p450 3a1 appears to involve the cova ...20147841342
[a new view of estradiol biotransformation in the body. estradiol metabolism in the erythrocytes via the peroxidase reaction].the study has established that in the presence of horseradish peroxidase, estradiol was subject to oxidative destruction under the action of hydrogen peroxide via the peroxidase reaction. the stoichiometric ratio of the hydrogen peroxide consumption to estradiol oxidation is 1:1 in this peroxidase reaction. estradiol peroxidation was found to be catalyzed by methemoglobin by the same order as in case of horseradish peroxidase. based on these results and the fact that estradiol is bound to erythr ...20147950785
inactivation of horseradish peroxidase by 3,5-dicarbethoxy-2,6-dimethyl-4-ethyl-1,4-dihydropyridine.in the presence of h2o2, horseradish peroxidase (hrp) catalyzes the one-electron oxidation of a porphyrinogenic agent, 3,5-dicarbethoxy-2,6-dimethyl-4-ethyl-1,4-dihydropyridine (ddep), leading to formation of an ethyl radical, inactivation of the enzyme, and formation of an altered heme product. the loss of heme during the inactivation of hrp was dependent on the duration of exposure to ddep as well as the concentration of h2o2 and ddep. the pseudo first order rate constant for the oxidation of ...20147696541
a system of parallel septa in crayfish nerve fibers.certain axons in the abdominal roots and nerve cord of crayfish contain a system of regularly spaced, parallel transverse septa with a periodicity of about 2 micro. each septum is composed of two roughly parallel membranes, separated by a gap of 150-400 a. the two membranes are frequently fenestrated by pores 550-2000 a in diameter, each occupied by a microtubule. filaments are occasionally seen bridging the gap between the microtubule and the edge of the pore. the membranes of the septa are con ...20144187704
cytoarchitectural fields and retinal termination: an axonal transport study of laminar organization in the avian optic tectum.the cytoarchitecture in the retinoreceptive zone of the pigeon optic tectum has been studied in nissl-stained sections taken in four planes. as suggested by a previous study, two cytoarchitectural fields are present. reconstructed views of the tectum show that the fields are separated by a narrow transition zone approximating to the tectal representation of the retina's horizontal meridian. in field 1 (which is upper and rostral), sublayer iib is wide, iic wide and trilaminate, iid narrow and ii ...20144094692
demonstration of ipsilateral retinocollicular projections in the tree shrew (tupaia glis).ipsilateral retinocollicular projections labeled by anterograde transport of wheatgerm agglutinin-horseradish peroxidase (hrp) conjugate in the tree shrew were examined. for those animals in which this pathway was demonstrated (4 of 14) ipsilateral collicular labeling extended across approximately the anterior two-thirds of the colliculus, with the exception of the extreme rostral pole. labeling was invariably punctuate and spaced at regular intervals in the lower stratum griseum superficiale. t ...20144052767
cell lineage of zebrafish blastomeres. iii. clonal analyses of the blastula and gastrula stages.aspects of the early lineages of blastomeres in the embryo of the zebrafish, brachydanio rerio have been described. because of the optical clarity of the embryo, lineages of selected cells can be followed directly by microscopy through many cell divisions. also, it is shown here that the fluorescent molecules fluorescein-dextran and rhodamine-horseradish peroxidase can be used as cell lineage tracers, marking the clonal progeny of founding blastomeres. the labeled cells can be easily visualized ...20143972184
homing behaviour of axons in the embryonic vertebrate brain.in embryonic nervous systems, growing axons must often travel long distances through diverse extracellular terrains to reach their postsynaptic partners. in most embryos, axons grow to their appropriate targets along particular tracts or nerves, as though they were following guidance cues confined to specific pathways. for example, in all vertebrates, axons from the retina invariably grow to the tectum along the well-defined optic tract. yet, transplant experiments demonstrate that retinal axons ...20143960107
cellular physiology of the turtle visual cortex: distinctive properties of pyramidal and stellate neurons.the electrophysiological properties of neurons in the three-layered dorsal cortex of the turtle, pseudemys scripta elegans, have been studied in vitro. intracellular recordings suggested two distinct classes of neuronal behavior. cell labeling with either lucifer yellow or horseradish peroxidase revealed that these behaviors correlated with the two morphological classes of cortical neurons: pyramidal cells and stellate cells. examination of golgi-stained neurons of dorsal cortex did not uncover ...20143944618
[amperometric sensor for recording the results of immunoenzyme analysis].a technique for quantitative determining horseradish peroxidase was developed using an amperometric sensor that makes it possible to register up to 50 pm of the enzyme in the reaction of the peroxidase oxidation of iodide ions by hydrogen peroxide. the sensor, composed of combined carbon and ag/agcl electrodes, is intended for enzyme immunoassay and may be used for registering the results in the very wells of the polystyrene plates widely used in clinics and laboratories. the dependences of the ...20143911203
stabilization of the substrate reaction of horseradish peroxidase with o-phenylenediamine in the enzyme immunoassay.when the horseradish peroxidase reaction is stopped with acid, the decay of unconverted hydrogen peroxide is responsible for the further oxidation of o-phenylenediamine. this leads to a time-dependent flattening of the standard curve in the enzyme immunoassay, after the reaction has been stopped. addition of reducing agents, such as sulphite ions, to the stopping solution, prevents the further oxidation of o-phenylenediamine by completely reducing the remaining hydrogen peroxide. the developed c ...20143884727
the permeability of hyperplastic oral epithelium.an epithelial hyperplasia is one of the reactions of skin and oral mucosa to chemical and mechanical insult. it is usually assumed that this reaction produces a more effective epithelial barrier, but there is no information as to whether a less permeable tissue results. to examine this question, hyperplasia was induced in the cheek pouches of hamsters by either chemical treatment with 0.0025% tpa in acetone or by mechanical abrasion with a rotating mop; untreated hamsters served as controls. the ...20143925100
the trophotaenial placenta of a viviparous goodeid fish. iii: protein uptake by trophotaeniae, the embryonic component.protein uptake and degradation by trophotaenial cells of the viviparous goodeid fish ameca splendens were studied colorimetrically and ultrastructurally using horseradish peroxidase (hrp) as a tracer and acid (acpase) and alkaline (alpase) phosphatase cytochemistry. trophotaeniae are ribbon-like external projections of the embryonic gut that are equivalent to greatly hypertrophied intestinal villi. during gestation within the ovarian lumen, trophotaeniae are directly apposed to the internal ovar ...20144067530
connections between the cerebellum and hypothalamus in the tree shrew (tupaia glis).following injections of a wheat germ agglutinin-horseradish peroxidase (wga-hrp) conjugate into representative areas of cerebellar cortex of tree shrew (tupaia glis) retrogradely labeled cells were found in posterior, lateral and dorsal hypothalamic areas and in the lateral mammillary nucleus. these represent monosynaptic hypothalamocerebellar cortical projections. anterogradely labeled axons were also traced into various areas of the contralateral hypothalamus subsequent to injections of wga-hr ...20143986533
a new restriction endonuclease-based method for highly-specific detection of dna targets from methicillin-resistant staphylococcus aureus.pcr multiplexing has proven to be challenging, and thus has provided limited means for pathogen genotyping. we developed a new approach for analysis of pcr amplicons based on restriction endonuclease digestion. the first stage of the restriction enzyme assay is hybridization of a target dna to immobilized complementary oligonucleotide probes that carry a molecular marker, horseradish peroxidase (hrp). at the second stage, a target-specific restriction enzyme is added, cleaving the target-probe d ...201424831802
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