Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| multienzyme-nanoparticles amplification for sensitive virus genotyping in microfluidic microbeads array using au nanoparticle probes and quantum dots as labels. | a novel microfluidic device with microbeads array was developed and sensitive genotyping of human papillomavirus was demonstrated using a multiple-enzyme labeled oligonucleotide-au nanoparticle bioconjugate as the detection tool. this method utilizes microbeads as sensing platform that was functionalized with the capture probes and modified electron rich proteins, and uses the horseradish peroxidase (hrp)-functionalized gold nanoparticles as label with a secondary dna probe. the functionalized m ... | 2011 | 21872460 |
| protein diffusion in photopolymerized poly(ethylene glycol) hydrogel networks. | in this study, protein diffusion through swollen hydrogel networks prepared from end-linked poly(ethylene glycol)-diacrylate (peg-da) was investigated. hydrogels were prepared via photopolymerization from peg-da macromonomer solutions of two molecular weights, 4600 da and 8000 da, with three initial solid contents: 20, 33 and 50 wt/wt% peg. diffusion coefficients for myoglobin traveling across the hydrogel membrane were determined for all peg network compositions. the diffusion coefficient depen ... | 2011 | 21873762 |
| assessment of permeability in barrier type of endothelium in brain using tracers: evans blue, sodium fluorescein, and horseradish peroxidase. | blood-brain barrier (bbb) constituted primarily by the capillary endothelial cells functions to maintain a constant environment for the brain, by preventing or slowing down the passage of a variety of blood-borne substances, such as serum proteins, chemical compounds, ions, and hormones from the circulation into the brain parenchyma. various diseases such as brain tumors, epilepsy, and sepsis disturb the bbb integrity leading to enhanced permeability of brain microvessels. in animal models, a va ... | 2011 | 21874465 |
| Co-expression of interleukin 12 enhances antitumor effects of a novel chimeric promoter-mediated suicide gene therapy in an immunocompetent mouse model. | The human telomerase reverse transcriptase (hTERT) promoter has been widely used in target gene therapy of cancer. However, low transcriptional activity limited its clinical application. Here, we designed a novel dual radiation-inducible and tumor-specific promoter system consisting of CArG elements and the hTERT promoter, resulting in increased expression of reporter genes after gamma-irradiation. Therapeutic and side effects of adenovirus-mediated horseradish peroxidase (HRP)/indole-3-acetic ( ... | 2011 | 21875574 |
| highly sensitive rapid chemiluminescent immunoassay using the dnazyme label for signal amplification. | a novel trace tag for chemiluminescent (cl) immunoassay was designed by using dnazyme to functionalize antibody-labeled au nanoparticles (aunps). the trace tag showed an excellent ability to catalyze the oxidation of luminol by hydrogen peroxide, leading to strong cl emission. by coupling the trace tag with a passive mixing accelerated immunoreaction system, a highly sensitive rapid flow-through cl immunoassay method was proposed. using carcinoembryonic antigen (cea) as a model analyte, the capt ... | 2011 | 21881672 |
| urothelial plaque formation in post-golgi compartments. | urothelial plaques are specialized membrane domains in urothelial superficial (umbrella) cells, composed of highly ordered uroplakin particles. we investigated membrane compartments involved in the formation of urothelial plaques in mouse umbrella cells. the golgi apparatus did not contain uroplakins organized into plaques. in the post-golgi region, three distinct membrane compartments containing uroplakins were characterized: i) small rounded vesicles, located close to the golgi apparatus, were ... | 2011 | 21887288 |
| detecting multiple proteins by western blotting using same-species primary antibodies, precomplexed serum, and hydrogen peroxide. | western blot detection of multiple proteins is challenged by the need to use antibodies from the same species and the harsh stripping methods that can remove protein or reduce protein antigenicity. quenching using 27% hydrogen peroxide was developed as an alternative to stripping to inhibit horseradish peroxidase used to detect secondary antibodies. to detect two epitopes with same-species primary antibodies, quenching was followed by incubation in a precomplexed mixture of primary and secondary ... | 2011 | 21888891 |
| enzymatic treatment and detoxification of acid orange 7 from textile wastewater. | a crude preparation of horseradish roots was used as a low-purity source of horseradish peroxidase (hrp) in dye decolorization experiments. the technical feasibility of the process was studied in bench scale for enzymatic removal of acid orange 7 (ao7), a synthetic dye. further studies were carried out to understand the effects of process parameters such as ph value, h(2)o(2) level, concentrations of the synthetic dye, and hrp during enzyme-mediated dye degradation. experimental data revealed th ... | 2011 | 21892667 |
| immunoblotting and immunodetection. | immunoblotting (western blotting) is used to identify specific antigens recognized by polyclonal or monoclonal antibodies. this unit provides protocols for all steps, starting with solubilization of the protein samples, usually by means of sds and reducing agents. following solubilization, the material is separated by sds-page and the antigens are electrophoretically transferred to a membrane, a process that can be monitored by reversible staining with ponceau s. the transferred proteins are bou ... | 2011 | 21898339 |
| Development and validation of a standardized ELISA for the detection of soluble Fc-epsilon-RI in human serum. | The aim of this study was to develop a standardized enzyme-linked immunosorbent assay (ELISA) for detection of human soluble Fc-epsilon-RI (sFceRI), a serum isoform of the high affinity IgE receptor. A recombinant version of sFceRI was produced in baculovirus and used as standard. ELISA plates were coated with anti-mouse IgG followed by incubation with the monoclonal capture antibody CRA1. This FceRI-alpha-specific antibody binds to the stalk region of the protein and does not inhibit IgE-bindin ... | 2011 | 21903095 |
| Uricase-adsorbed carbon-felt reactor coupled with a peroxidase-modified carbon-felt-based H2O2 detector for highly sensitive amperometric flow determination of uric acid. | Uricase (urate oxidase, UOx) was adsorbed onto a porous carbon-felt (CF) surface and the resulting UOx-adsorbed CF (UOx-CF) was successfully used as a column-type enzyme reactor coupled with a peroxidase-adsorbed CF-based bioelectrocatalytic H(2)O(2) flow-detector to fabricate a flow-amperometric biosensor for uric acid. In this flow-biosensor system, H(2)O(2) produced in the UOx-CF reactor was cathodically detected by horseradish peroxidase (HRP) and a thionine (Th)-coadsorbed CF (HRP/Th-CF)-ba ... | 2012 | 21906900 |
| three-dimensional network polyamidoamine dendrimer-au nanocomposite for the construction of a mediator-free horseradish peroxidase biosensor. | a three-dimensional network pamam-au nanocomposite (3d-pamam-au nc) was prepared by using the first generation polyamidoamine dendrimer (g1 pamam) as the dispersant agent. the resultant 3d-pamam-au nc was successfully used as an immobilization matrix for the construction of a reagentless mediator-free horseradish peroxidase (hrp)-based h(2)o(2) biosensor on a multi-walled carbon nanotubes (mwcnts) modified glassy carbon electrode. with the advantages of the three-dimensional network, the organic ... | 2011 | 21909571 |
| enzyme-mimic activity of ferric nano-core residing in ferritin and its biosensing applications. | ferritins are nanoscale globular protein cages encapsulating a ferric core. they widely exist in animals, plants, and microbes, playing indispensable roles in iron homeostasis. interestingly, our study clearly demonstrates that ferritin has an enzyme-mimic activity derived from its ferric nanocore but not the protein cage. further study revealed that the mimic-enzyme activity of ferritin is more thermally stable and ph-tolerant compared with horseradish peroxidase. considering the abundance of f ... | 2011 | 21910434 |
| Enzyme-nanoporous gold biocomposite: excellent biocatalyst with improved biocatalytic performance and stability. | Applications involving biomolecules, such as enzymes, antibodies, and other proteins as well as whole cells, are often hampered by their unstable nature at extremely high temperature and in organic solvents. | 2011 | 21912676 |
| [The influence of oxygen on the inhibition between Streptococcus oligofermentans and Streptococcus mutans]. | To investigate the effect of environmental oxygen on the inhibition between Streptococcus oligofermentans (So) and Streptococcus mutans (Sm) and the producibilities of hydrogen peroxide by So. | 2011 | 21914377 |
| functional networks of parvalbumin-immunoreactive neurons in cat auditory cortex. | inhibitory interneurons constitute ∼20% of auditory cortical cells and are essential for shaping sensory processing. connectivity patterns of interneurons in relation to functional organization principles are not well understood. we contrasted the connection patterns of parvalbumin-immunoreactive cells in two functionally distinct cortical regions: the tonotopic, narrowly frequency-tuned module [central narrow band (cnb)] of cat central primary auditory cortex (ai) and the nontonotopic, broadly ... | 2011 | 21917816 |
| A heme peroxidase with a functional role as an L-tyrosine hydroxylase in the biosynthesis of anthramycin. | We report the first characterization and classification of Orf13 (S. refuineus) as a heme-dependent peroxidase catalyzing the ortho-hydroxylation of L-tyrosine to L-DOPA. The putative tyrosine hydroxylase coded by orf13 of the anthramycin biosynthesis gene cluster has been expressed and purified. Heme b has been identified as the required cofactor for catalysis, and maximal L-tyrosine conversion to L-DOPA is observed in the presence of hydrogen peroxide. Preincubation of L-tyrosine with Orf13 pr ... | 2011 | 21919439 |
| [Tumor necrosis factor-a promote permeability of human umbilical vein endothelial cells via activating RhoA-ERK1/2 pathway]. | Tumor necrosis factor-a (TNF-a) is known to induce changes in endothelial cell morphology and permeability. The aim of this study is to determine the underlying signaling mechanisms involved in these responses. | 2011 | 21924080 |
| multianalyte immunoassay chip for detection of tumor markers by chemiluminescent and colorimetric methods. | most cancers developed an elevation of the level of at least two markers associated with their incidence. simultaneous detection of multi-tumor markers associated with a particular type of cancer plays an important role in cancer diagnostic. here, a multianalyte immunoassay chip for simple and sensitive detection of tumor markers with chemiluminescent and colorimetric methods was proposed, in which carcinoembryonic antigen (cea) and carbohydrate antigen (ca19-9) that associated with colorectal c ... | 2011 | 21928078 |
| development of gaba-, glycine-, and glutamate-immunopositive boutons onto rat jaw-opening motoneurons. | inhibitory and excitatory synaptic inputs onto trigeminal motoneurons play an important role in coordinating jaw movements. previously, we reported that the phenotype of the inhibitory boutons apposing the somata of jaw-closing (jc) motoneurons changes from gaba-positive (gaba(+) ) to predominantly glycine-positive (gly(+) ) during development. in the present study, we investigated the development of inhibitory and excitatory boutons apposing antagonistic jaw-opening (jo) motoneurons (anterior d ... | 2011 | 21935946 |
| Controlling Fibroblast Proliferation with Dimensionality-Specific Response by Stiffness of Injectable Gelatin Hydrogels. | We report an injectable hydrogel system with tunable stiffness for controlling the proliferation rate of human fibroblasts (HFF-1) in both two-dimensional (2D) and three-dimensional (3D) culture environments for potential use as a wound dressing material. The hydrogel composed of gelatin-hydroxyphenylpropionic acid (Gtn-HPA) conjugate was formed by the oxidative coupling of HPA moieties catalyzed by hydrogen peroxide (H(2)O(2)) and horseradish peroxidase (HRP). The stiffness of the hydrogels was ... | 2011 | 21943785 |
| a multi-amplification aptasensor for highly sensitive detection of thrombin based on high-quality hollow copt nanoparticles decorated graphene. | in this work, we have successfully demonstrated a facile strategy to incorporate high-quality hollow copt bimetal alloy nanoparticles (hcopt) onto reduced graphene oxide sheet (hcopt-rgs). an advanced sandwich-type electrochemical aptasensor for thrombin was proposed by using the hcopt-rgs conjugates as secondary label. the formed conjugates provided large surface area for loading plentiful redox probe thionine (thi), horseradish peroxidase (hrp) and secondary aptamer (apt ii) with good stabilit ... | 2011 | 21944185 |
| One step immobilization of peptides and proteins by using modified parylene with formyl groups. | One-step immobilization method for peptides and proteins is developed by using modified parylene film with formyl groups which is suitable for microplate-based immunoassay and SPR biosensor application. The immobilization of peptides and proteins is achieved through the covalent bonding of the formyl group with the primary amine groups of peptides and proteins, which no additional activation step is required. In this work, the immobilization efficiency of parylene-H is estimated in comparison wi ... | 2011 | 21945140 |
| differential effects of nutritional and non-nutritional therapies on intestinal barrier function in an in vitro model. | diminished intestinal epithelial barrier function contributes to the pathogenesis of crohn's disease. clinical and experimental studies propose that increased tumor necrosis factor (tnf)-α promotes barrier dysfunction. the aim of this study was to investigate the effects of nutritional and other therapies upon intestinal barrier function in the presence of tnf-α in an in vitro model. | 2012 | 21953313 |
| cytotoxicity and glycan-binding profile of a d-galactose-binding lectin from the eggs of a japanese sea hare (aplysia kurodai). | a divalent cation-independent 16 kda d-galactose binding lectin (akl-2) was isolated from eggs of sea hare, aplysia kurodai. the lectin recognized d-galactose and d-galacturonic acid and had a 32 kda dimer consisting of two disulfide-bonded 16 kda subunits. eighteen n-terminus amino acids were identified by edman degradation, having unique primary structure. lectin blotting analysis with horseradish peroxidase-conjugated lectins has shown that akl-2 was a glycoprotein with complex type oligosacc ... | 2011 | 21953532 |
| [Interconnections of the pallidum, pedunculopontine nucleus, zona incerta, and deep mesencephalic nucleus--the structures of the basal ganglia morpho-functional system]. | Method of anterograde and retrograde axonal transport of horseradish peroxidase was used to study the organization of projections of different substructures of zona incerta (ZI), pedunculopontine nucleus (PPN), deep mesencephalic nucleus (DMN) complex, and functionally distinct structures of the pallidum of dog brain (n=20). It was found that pallidum and nucleus entope-duncularis are connected by reciprocal projections with dorsal, ventral and caudal sectors of ZI, as well as with DMN, lateral ... | 2011 | 21954703 |
| kinetics of enzyme-catalyzed cross-linking of feruloylated arabinan from sugar beet. | ferulic acid (fa) groups esterified to the arabinan side chains of pectic polysaccharides can be oxidatively cross-linked in vitro by horseradish peroxidase (hrp) catalysis in the presence of hydrogen peroxide (h(2)o(2)) to form ferulic acid dehydrodimers (difas). the present work investigated whether the kinetics of hrp catalyzed cross-linking of fa esterified to α-(1,5)-linked arabinans are affected by the length of the arabinan chains carrying the feruloyl substitutions. the kinetics of the h ... | 2011 | 21954887 |
| tumor-targeted gene therapy using adv-afp-hrpc/iaa prodrug system suppresses growth of hepatoma xenografted in mice. | clinical efficacy of current therapies for hepatocellular carcinoma (hcc) treatment is limited. indole-3-acetic acid (iaa) is non-toxic for mammalian cells. oxidative decarboxylation of iaa by horseradish peroxidase (hrp) leads to toxic effects of iaa. the purpose of this study was to investigate the effects of a novel gene-targeted enzyme prodrug therapy with iaa on hepatoma growth in vitro and in vivo mouse hepatoma models. we generated a plasmid using adenovirus to express hrp isoenzyme c (hr ... | 2011 | 21959967 |
| recombinant exon-encoded resilins for elastomeric biomaterials. | resilin is an elastomeric protein found in specialized regions of the cuticle of most insects, providing outstanding material properties including high resilience and fatigue lifetime for insect flight and jumping needs. two exons (1 and 3) from the resilin gene in drosophila melanogaster were cloned and the encoded proteins expressed as soluble products in escherichia coli. a heat and salt precipitation method was used for efficient purification of the recombinant proteins. the proteins were so ... | 2011 | 21963157 |
| A versatile and highly sensitive probe for Hg(II), Pb(II) and Cd(II) detection individually and totally in water samples. | The detection of heavy metal ions using enzyme-linked immunosorbent assays (ELISA) has been reported by several research groups. However, highly sensitive and selective detection of total heavy metal ions using ELISA is a major technical limitation. Here we describe the development of a versatile and highly sensitive probe combining goat anti-mice IgG, colloidal gold nanoparticles (AuNPs) and horseradish peroxidase (HRP). We demonstrate the utility of this probe using three kinds of heavy metal ... | 2011 | 21975341 |
| artemin as an efficient molecular chaperone. | artemin is an abundant thermostable protein in artemia encysted embryos under stress. it is considered as a stress protein, as its highly regulated expression is associated with stress resistance in this crustacea. in the present study, artemin has been shown to be a potent molecular chaperone with high efficacy. artemin is capable of inhibiting the chemical aggregation of proteins such as carbonic anhydrase (ca) and horseradish peroxidase (hrp) at unique molar ratios of chaperone to substrates ... | 2011 | 21979748 |
| nociceptive afferents to the premotor neurons that send axons simultaneously to the facial and hypoglossal motoneurons by means of axon collaterals. | it is well known that the brainstem premotor neurons of the facial nucleus and hypoglossal nucleus coordinate orofacial nociceptive reflex (onr) responses. however, whether the brainstem pns receive the nociceptive projection directly from the caudal spinal trigeminal nucleus is still kept unclear. our present study focuses on the distribution of premotor neurons in the onr pathways of rats and the collateral projection of the premotor neurons which are involved in the brainstem local pathways o ... | 2011 | 21980505 |
| Multiarmed star-like platinum nanowires with multienzyme assembly for direct electronic determination of carcinoembryoninc antigen in serum. | A new electrochemical immunoassay strategy for direct detection of carcinoembryoninc antigen (CEA) in serum was developed by using multiarmed star-like platinum nanowires (PtNWs) with biomolecular assembly as signal tags on an anti-CEA-functionalized graphene sensing platform. Initially, the PtNWs were synthesized via a wet chemical method, and then the synthesized PtNWs were used for the co-immobilization of CEA and horseradish peroxidase (HRP). Compared with platinum nanoparticles, the prepare ... | 2011 | 21982336 |
| A microfluidic device based on a screen-printed carbon electrode with electrodeposited gold nanoparticles for the detection of IgG anti-Trypanosoma cruzi antibodies. | In this article we report the development of an integrated microfluidic system coupled to a screen-printed carbon electrode (SPCE) applied to the quantitative determination of IgG specific antibodies present in serum samples of patients that suffer from Chagas disease. This relevant parasitic infection caused by the hemoflagellate protozoan Trypanosoma cruzi represents a major public health concern in Latin America. In order to perform the detection of mentioned antibodies, SPCE coupled to a mic ... | 2011 | 21984978 |
| occupational ige-mediated softwood allergy: characterization of the causative allergen. | allergic reactions to wood dust allergens are rare, and only few in vitro diagnostic tools and information about relevant allergens are available. to differentiate between protein-based allergy and probably clinically silent glycogenic sensitization, it is helpful to characterize the relevant protein allergens and specify ige binding. the current case report deals with the occupational softwood allergy of a carpenter exposed to different wood dusts. skin tests and ige tests against wood were per ... | 2012 | 21986217 |
| value of component based diagnostics in ige-mediated hymenoptera sting reactions. | stings by insects can precipitate many signs and symptoms of dermatological and ocular diseases. of particular importance is the anaphylaxis after hymenoptera stings. selection of the appropriate venom for immunotherapy requires a precise diagnosis, which is frequently difficult to confirm since the history presented by the patient is many times not conclusive and diagnostic tests are often positive for bee venom (bv) and vespula venom (vv). this double positivity is either caused by true double ... | 2012 | 21995714 |
| validated enzyme-linked immunosorbent assay for determination of rosuvastatin in plasma at picogram level. | in this study, a highly sensitive enzyme-linked immunosorbent assay (elisa) has been developed and validated for the determination of rosuvastatin (ros) in plasma samples at picogram level. the assay employed a polyclonal antibody that specifically recognizes ros with high affinity, and ros conjugate of bovine serum albumin (ros-bsa) immobilized onto microplate wells as a solid phase. the assay involved a competitive binding reaction between ros, in plasma sample, and the immobilized ros-bsa for ... | 2011 | 21998019 |
| Protein heteroconjugation by the peroxidase-catalyzed tyrosine coupling reaction. | Combining different proteins can integrate the functions of each protein to produce novel protein conjugates with wider ranges of applications. We have previously introduced a peptide containing tyrosine residues (Y-tag) at the C-terminus of Escherichia coli alkaline phosphatase (BAP). The tyrosine residues in the Y-tag were efficiently recognized by horseradish peroxidase (HRP) and were site-specifically cross-linked with each other to yield BAP homoconjugates. In this study, the HRP-catalyzed ... | 2011 | 21999311 |
| evaluation of the forrester-hepburn mechanism as an artifact source in esr spin-trapping. | nitrone spin traps such as 5,5-dimethyl-1-pyrroline-n-oxide (dmpo) are commonly used for free radical detection. though proven examples are rare, artifact formation must be considered. for example, the forrester-hepburn mechanism yields the same radical adduct as that formed by genuine radical trapping. a hydroxylamine is formed by nucleophilic attack of the substrate on dmpo and subsequently oxidized to the respective nitroxide radical. one potential candidate for this artifact is the sulfur tr ... | 2011 | 22004308 |
| detection of cortisol at a gold nanoparticle|protein g-dtbp-scaffold modified electrochemical immunosensor. | an ultrasensitive electrochemical immmunosensor was demonstrated to be capable of detecting the hormone cortisol down to concentrations as low as 16 pg ml(-1). in addition, the immunosensor displayed a sensitivity of 1.6 μa pg(-1) ml(-1) and a linear range up to ∼2500 pg ml(-1) of cortisol. this immunosensor was constructed based on a au nanoparticle|dimethyl 3,3'-dithiobispropionimidate·2hcl (dtbp)-protein g scaffold-modified au electrode. in this work, the au nanoparticles were used to increas ... | 2011 | 22005508 |
| electrochemical biosensors for on-chip detection of oxidative stress from immune cells. | seamless integration of biological components with electrochemical sensors is critical in the development of microdevices for cell analysis. the present paper describes the integration miniature au electrodes next to immune cells (macrophages) in order to detect cell-secreted hydrogen peroxide (h(2)o(2)). photopatterning of poly(ethylene glycol) (peg) hydrogels was used to both immobilize horseradish peroxidase molecules onto electrodes and to define regions for cell attachment in the vicinity o ... | 2011 | 22007269 |
| optimization of expression conditions for production of anti-colorectal cancer monoclonal antibody co17-1a in baculovirus-insect cell system. | the baculovirus-insect cell system is considered a feasible expression system for recombinant glycoprotein production due to its several advantages, including high capacity, flexibility, and glycosylation capability. however, accurate titering of the recombinant baculovirus is required to ensure high expression in insect cells using a commercial and expensive immunoassay titer kit in which the envelope glycoprotein of the autographa californica multiple nucleopolyhedrovirus (acmnpv)-type baculov ... | 2011 | 22008068 |
| construction and interrogation of enzyme microarrays using scanning electrochemical microscopy - optimisation of adsorption and determination of enzymatic activity. | scanning electrochemical microscopy (secm) has been used to image and study the catalytic activity of horseradish peroxidase (hrp) immobilised in a patterned fashion onto glass slides. microarrays of hrp islands could be deposited on amino-modified glass slides using glutaraldehyde crosslinking combined with the secm being used as a micro-deposition device. the enzymatic activity of the immobilised enzyme on the surface was in the presence of its substrate observed to give rise to substantial po ... | 2011 | 22016876 |
| a amperometric biosensor for hydrogen peroxide by adsorption of horseradish peroxidase onto single-walled carbon nanotubes. | development of a highly sensitive nanostructured electrochemical biosensor based on the integrated assembly of horseradish peroxidase (hrp) and single-walled carbon nanotubes (swnts) is described. in this study, we describe the use of a sodium cholate suspension-dialysis method to adsorb the horseradish peroxidase (hrp) onto single-walled carbon nanotubes (swnts). we demonstrate that hrp-swnts conjugates can be assembled into amperometric biosensors which l-cysteine were assembled on a gold elec ... | 2012 | 22019049 |
| a strategy for constructing sensitive and renewable molecularly imprinted electrochemical sensors for melamine detection. | a novel strategy for preparing highly sensitive and easily renewable molecularly imprinted polymer (mip) sensors was proposed. using melamine (ma) as the template molecule, mip particles were synthesized and embedded in a solid paraffin carbon paste to prepare the mip sensor. ma was indirectly determined from the competition between the reactions of ma and horseradish peroxidase-labeled ma (ma-hrp) with the vacant cavities. the detection signals were amplified because of enzymatic reaction to th ... | 2011 | 22023859 |
| antibody-based surfaces: rapid characterization using two complementary colorimetric assays. | finding a general solution for optimizing the grafting of antibody on solid surfaces is difficult due to the variety of material, grafting principles and chemistries or surface formats available (beads, microplates, fibers, etc.). pre-screening methods able to assess grafting efficiency (ge) and specific activity (sa) are required. in this context, we present here two colorimetric assays that can be used on a wide variety of surface format, chemistry, etc. the first one, adeca (amino density est ... | 2011 | 22023873 |
| a novel approach to construct a horseradish peroxidase|hydrophilic ionic liquids|au nanoparticles dotted titanate nanotubes biosensor for amperometric sensing of hydrogen peroxide. | the direct electrochemistry of horseradish peroxidase (hrp) on a novel sensing platform modified glassy carbon electrode (gce) has been achieved. this sensing platform consists of nafion, hydrophilic room-temperature ionic liquid (rtil) and au nanoparticles dotted titanate nanotubes (gnps-tnts). the composite of rtil and gnps-tnts was immobilized on the electrode surface through the gelation of a small amount of hrp aqueous solution. the composite was characterized by transmission electron micro ... | 2012 | 22024591 |
| A sensitive and rapid immunoassay for quantification of testosterone by microchip electrophoresis with enhanced chemiluminescence detection. | A sensitive and rapid approach to perform testosterone (T) competitive immunoassay by microchip electrophoresis (MCE) with chemiluminescence (CL) detection was developed. The assay is based on the competitive immunoreactions between T and N-(4-aminobutyl)-N-ethylisoluminol-labeled T (ABEI-T) with a limited amount of antibody (Ab), and the rapid electrophoretic separation of an equilibrated mixture of ABEI-T-Ab complex and free ABEI-T, followed by CL detection using horseradish peroxidase-catalyz ... | 2011 | 22025074 |
| a photoelectrochemical immunosensor for benzo[a]pyrene detection amplified by bifunctional gold nanoparticles. | ultrasensitive photoelectrochemical immunoassay of polycyclic aromatic hydrocarbon (pah) is proposed using an antibody-modified nanostructured tio(2) electrode combined with bifunctional gold nanoparticles modified with the pah antigen and horseradish peroxidase (hrp). the hrp-catalyzed reaction prompts the electron transfer between the electrode and electrolyte causing an excellent photocatalytic performance. | 2011 | 22027936 |
| nanotube-based colorimetric probe for ultrasensitive detection of ataxia telangiectasia mutated protein. | we have developed a nanotube-based colorimetric probe using multiwalled carbon nanotubes (mwnts), anti-immunoglobulin g (anti-igg), and horseradish peroxidase (hrp). the probe was used as an alternative to conventional colorimetric conjugates to obtain amplified signals in a sandwich-type immunoassay for ataxia telangiectasia mutated (atm), a potential biomarker for radiation doses and cancers. results show that the mwnt-based probe colorimetry was 5000 times more sensitive than a conventional e ... | 2011 | 22029608 |
| assembly of graphene oxide-enzyme conjugates through hydrophobic interaction. | biochemical and biomedical applications of graphene oxide (go) critically rely on the interaction of biomolecules with it. it has been previously reported that the biological activity of the go-enzyme conjugate decreases due to electrostatic interaction between the enzymes and go. herein, the immobilization of horseradish peroxidase (hrp) and oxalate oxidase (oxox) on chemically reduced graphene oxide (crgo) are reported. the enzymes can be adsorbed onto crgo directly with a tenfold higher enzym ... | 2012 | 22038754 |
| enzyme immunoassay for tenuazonic acid in apple and tomato products. | the alternaria mycotoxin tenuazonic acid was derivatized with succinic anhydride and conjugated to keyhole limpet hemocyanin (klh) and to horseradish peroxidase (hrp), respectively. the klh conjugate was used to produce polyclonal antibodies in rabbits. a competitive direct enzyme immunoassay (eia) for tenuazonic acid was established, which was moderately sensitive for tenuazonic acid [50% inhibition concentration (ic(50)): 320 ± 130 ng/ml] but strongly reacted with tenuazonic acid acetate (ic(5 ... | 2011 | 22054343 |
| sandwich elisa for detection of horse meat in raw meat mixtures using antisera to muscle soluble proteins. | a double-antibody sandwich elisa (enzyme-linked immunosorbent assay) has been successfully developed for the detection of defined amounts of horse meat (1-50%) in unheated meat mixtures. the assay uses horse-specific antibodies obtained by immunoadsorption of the crude horse antisera onto immobilised sarcoplasmic extracts from chicken, beef and pig to remove cross-reacting antibodies. the purified antibodies bound to a solid support sequester horse muscle soluble proteins from meat mixtures. fur ... | 1988 | 22055244 |
| combinatorial glycoarray. | glycolipid-protein interactions are increasingly recognised as critical to numerous and diverse biological processes, including immune recognition, cell-cell signalling, pathogen adherence, and virulence factor binding. previously, such carbohydrate-lectin interactions have been assessed in vitro largely by assaying protein binding against purified preparations of single glycolipids. recent observations show that certain disease-associated autoantibodies and other lectins bind only to complexes ... | 2012 | 22057541 |
| live diatom silica immobilization of multimeric and redox-active enzymes. | living organisms are adept in forming inorganic materials (biominerals) with unique structures and properties that exceed the capabilities of engineered materials. biomimetic materials syntheses are being developed that aim at replicating the advantageous properties of biominerals in vitro and endow them with additional functionalities. recently, proof-of-concept was provided for an alternative approach that allows for the production of biomineral-based functional materials in vivo. in this appr ... | 2012 | 22057862 |
| multifunctional gold-silica nanostructures for ultrasensitive electrochemical immunoassay of streptomycin residues. | a facile and simple electrochemical immunoassay for ultrasensitive determination of streptomycin residues (str) in food was designed by using nanogold-assembled mesoporous silica (gmsns) as bionanolabels on a three-dimensional redox-active organosilica-functionalized sensing interface. to construct such a sensing interface, we initially synthesized organosilica colloids by using wet chemical method, and then utilized the prepared colloidal organosilica nanocomposites for the immobilization of mo ... | 2011 | 22059488 |
| simultaneous electrochemical detection of multiple analytes based on dual signal amplification of single-walled carbon nanotubes and multi-labeled graphene sheets. | in this work, a sandwich-type electrochemical aptasensor for simultaneous sensitive detection of platelet-derived growth factor (pdgf) and thrombin is fabricated. reduced graphene oxide sheets (rgs) are used as matrices to immobilize the redox probes, which are subsequently coated with platinum nanoparticles (ptnps) to form the ptnps-redox probes-rgs nanocomposites. with the employment of the as prepared nanocomposites, a signal amplification strategy was described based on bienzyme (glucose oxi ... | 2012 | 22061494 |
| development of phosphonate modified fe 1-x mnxfe2o4 mixed ferrite nanoparticles: novel peroxidase mimetics in enzyme linked immunosorbent assay. | a highly facile and feasible strategy on the fabrication of advanced intrinsic peroxidase mimetics based on mn(2+) doped mixed ferrite (mn(ii)(x)fe(ii)(1-x)fe(iii)(2)o(4)) nanoparticles was demonstrated for the quantitative and sensitive detection of mouse igg (as a model analyte). mn(2+) doped fe(1-x)mn(x)fe(2)o(4) nanoparticles were synthesized using varying ratios of mn(2+):fe(2+) ions and characterized by the well known complementary techniques. the increase of mn(2+) proportion had remarkab ... | 2011 | 22063549 |
| peroxidase-mediated dealkylation of tamoxifen, detected by electrospray ionization-mass spectrometry, and activation to form dna adducts. | tamoxifen (tam) is extensively used for the treatment and prevention of breast cancer. associated with tam treatment is a two- to eightfold increase in risk of endometrial cancer. to understand the mechanisms associated with this increased risk several pathways for tam metabolism and dna adduct formation have been studied. the purpose of this study was to investigate the role of peroxidase enzymes in the metabolism of tam and its activation to form dna adducts. using advanced tandem mass spectro ... | 2012 | 22064363 |
| p53-regulated increase in oxidative-stress--induced apoptosis in fuchs endothelial corneal dystrophy: a native tissue model. | this study compared susceptibility of fuchs endothelial corneal dystrophy (fecd) and normal corneal endothelial cells (cecs) to oxidative stress, and studied the mechanism of oxidative-stress-induced apoptosis in fecd-affected endothelium. | 2011 | 22064994 |
| nanomolar hydrogen peroxide detection using horseradish peroxidase covalently linked to undoped nanocrystalline diamond surfaces. | in this article, we report on the low-level detection of hydrogen peroxide, a key player in the redox signaling pathway and a toxic product in the cellular system, using a colorimetric solution assay. amine-terminated undoped nanocrystalline diamond thin films were grown on glass using a linear-antenna microwave plasma cvd process. the diamond surface consists mainly of -nh(2) termination. the aminated diamond surface was decorated with horseradish peroxidase (hrp) enzyme using carbodiimide coup ... | 2012 | 22066858 |
| Neisseria meningitidis induces platelet inhibition and increases vascular endothelial permeability via nitric oxide regulated pathways. | Despite antibiotic therapy, infections with Neisseria meningitidis still demonstrate a high rate of morbidity and mortality even in developed countries. The fulminant septicaemic course, named Waterhouse-Friderichsen syndrome, with massive haemorrhage into the adrenal glands and widespread petechial bleeding suggest pathophysiological inhibition of platelet function. Our data show that N. meningitidis produces the important physiological platelet inhibitor and cardiovascular signalling molec ... | 2011 | 22072136 |
| a new fluorescent pet probe for hydrogen peroxide and its use in enzymatic assays for l-lactate and d-glucose. | we present a new probe for the determination of hydrogen peroxide (hp). it is based on the yellow fluorophore 4-amino-1,8-napththalimide, coupled to p-anisidine (as a redox-active group) to form a probe that is based on photoinduced electron transfer (pet). the preparation of the probe (which we refer to as "hp green") was accomplished in four steps with good yield. its fluorescence is independent of ph in the physiological range and quenched by a pet process that occurs between the p-anisidine ... | 2011 | 22076816 |
| the possible use of native foot-and-mouth disease nonstructural protein 3a in a serological screening test. | abstract elisa's for antibodies to non-structural proteins of foot-and-mouth disease developed to date use recombinant proteins as antigens. to compare the antibody response to recombinant antigen and native antigen we developed an antigen capture elisa for foot-and-mouth protein 3a. the concentration of 3a protein in virus cultures was significantly higher in the cell debris than in the supernatant, which made it possible to use proteins directly eluted from cells separated from a virus culture ... | 1998 | 22077293 |
| synthesis and application of a macroporous boronate affinity monolithic column using a metal-organic gel as a porogenic template for the specific capture of glycoproteins. | a macroporous boronate affinity monolithic column was prepared and applied to specifically capture glycoproteins using metal-organic gels (mogs) as a porogenic template. this newly explored application of mogs has proven to be a more convenient method for the formation of macropores in contrast to traditional porogenic methods. the poly (3-acrylamidophenylboronic acid-co-ethylene dimethacrylate) monolithic columns were synthesized in stainless columns by in situ polymerization. to fabricate the ... | 2011 | 22078233 |
| 3-glycidoxypropyltrimethoxysilane mediated in situ synthesis of noble metal nanoparticles: application to hydrogen peroxide sensing. | the in situ synthesis is reported of noble metal nanoparticles via 3-glycidoxypropyltrimethoxysilane mediated reduction of 3-aminopropyltrimethoxysilane treated metal salts during sol-gel processing. the method described involves the synthesis of uniform spherical nanoparticles of gold, silver and palladium with controlled size that can be directly utilized for thin film preparation. a detailed study of the synthesis and application of gold nanoparticles to the electrochemical detection of hydro ... | 2012 | 22081133 |
| detection of enzymatically generated hydrogen peroxide by metal-based fluorescent probe. | we developed a metal-based fluorescent probe for h(2)o(2) called mbfh1, which has an iron complex as a reaction site for h(2)o(2) and a 3,7-dihydroxyphenoxazine derivative as the fluorescent reporter unit. the iron complex reacts quickly with h(2)o(2) to form oxidants, and then the oxidants convert the closely appended nonfluorescent 3,7-dihydroxyphenoxazine moiety to resorufin in an intramolecular fashion. the quick response to h(2)o(2) allows us to plot the enzymatic evolution of h(2)o(2). a c ... | 2011 | 22088146 |
| 1,1'-oxalyldiimidazole chemiluminescent enzyme immunoassay capable of simultaneously sensing multiple markers. | in order to rapidly and simultaneously quantify and screen trace levels of multiple biomarkers in a single sample, rapid 1,1'-oxalyldiimidazole chemiluminescence (odi cl) was applied as a biosensor of immunoassays using various enzymes such as alkaline phosphatase (alp) and horseradish peroxidise (hrp). (1) fluorescein was formed from the reaction of fluorescein diphosphate (fdp) and immuno-complex conjugated with alp. (2) resorufin was formed from the reaction between amplex red and h(2)o(2) in ... | 2012 | 22088260 |
| sensitive electrochemical immunosensor array for the simultaneous detection of multiple tumor markers. | a novel electrochemical immunosensor array for the simultaneous detection of multiple tumor markers was developed by incorporating electrochemically addressing immobilization and one signal antibody strategy. as a proof-of-principle, an eight-electrode array including six carbon screen-printed working electrodes was used as a base array for the analysis of two important tumor markers, carcinoembryonic antigen (cea) and α-fetoprotein (afp) and a horseradish peroxidase-labeled antibody was employe ... | 2012 | 22091469 |
| kinetic approach of aflatoxin b1-acetylcholinesterase interaction: a tool for developing surface plasmon resonance biosensors. | this work presents a kinetic approach of the interaction between acetylcholinesterase (ache) from electric eel and aflatoxin b1 (afb1) or its protein conjugate (e.g., afb1-hrp [horseradish peroxidase]) in order to develop a simple and sensitive detection method of these compounds. the dissociation constant k(d) of the ache/afb1-hrp interaction (0.4 μm) obtained with the surface plasmon resonance (spr) technique is very close to the inhibition constant reported in amperometric assay (k(i)=0.35 μm ... | 2012 | 22093609 |
| Effect of antibody modifications on its biomolecular binding as determined by surface plasmon resonance. | A surface plasmon resonance (SPR)-based procedure was developed to determine the effect of antibody modifications on its biomolecular binding behavior. Mouse immunoglobulin G (IgG) was immobilized on a protein A-functionalized gold-coated SPR chip. Goat anti-mouse IgG and its various commercially available modifications (i.e., conjugated with atto 550, atto 647, tetramethylrhodamine isothiocyanate [TRITC], horseradish peroxidase [HRP], or biotin) were employed in exactly the same concentration f ... | 2011 | 22093612 |
| identification of tyr74 and tyr177 as substrate oxidation sites in cationic cell wall-bound peroxidase from populus alba l. | cationic cell wall-bound peroxidase (cwpo-c) has the capability to oxidize sinapyl alcohol, ferrocytochrome c, and synthetic lignin polymers, unlike most peroxidases that have been characterized in flowering plants, such as horseradish peroxidase and arabidopsis thaliana peroxidase a2. it has been suggested that the oxidation site is located on the cwpo-c surface, and homology modeling and chemically modified cwpo-c studies suggest that tyr74 and/or tyr177 are possible participants in the cataly ... | 2011 | 22099451 |
| preparation and characterization of bismuth oxide nanoparticles-multiwalled carbon nanotube composite for the development of horseradish peroxidase based h₂o₂ biosensor. | in this work, preparation and characterization of a novel nanocomposite containing bismuth oxide (bi(2)o(3)) nanoparticles and multiwalled carbon nanotubes (mwcnts) was presented. powder x-ray diffraction (xrd) studies revealed that as-synthesized bi(2)o(3) nanoparticles are crystalline and belong to α-phase with monoclinic symmetry. field emission scanning electron microscopy (fesem) study results showed that the size of bi(2)o(3) nanoparticles is 50 nm. energy-dispersive x-ray (edx) spectra of ... | 2011 | 22099642 |
| pd nanoparticle assemblies--as the substitute of hrp, in their biosensing applications for h2o2 and glucose. | the spherical porous pd nanoparticle assemblies (npas) have been successfully synthesized by starch-assisted chemical reduction of pd(ii) species at room temperature. such pd npas are not simply used to enlarge the surface area and to promote the electron transfer. they also catalyze the reduction of h(2)o(2) which are regarded as horseradish peroxidase (hrp) substitutes in electron transfer process. by using them as electrocatalysts, as low as 6.8×10(-7) m h(2)o(2) can be detected with a linear ... | 2012 | 22100764 |
| an electrochemical aptasensor based on enzyme linked aptamer assay. | an aptamer is an artificial functional oligonucleic acid, which can interact with its target molecule with high affinity and specificity. enzyme linked aptamer assay (elaa) is developed to detect cocaine using aptamer fragment/cocaine configuration based on the affinity interaction between aptamer fragments with cocaine. the aptasensor was constructed by cleaving anticocaine aptamer into two fragments: one was assembled on a gold electrode surface, while the other was modified with biotin at 3'- ... | 2012 | 22100766 |
| Principles of conjugating quantum dots to proteins via carbodiimide chemistry. | The covalent coupling of nanomaterials to bio-recognition molecules is a critical intermediate step in using nanomaterials for biology and medicine. Here we investigate the carbodiimide-mediated conjugation of fluorescent quantum dots to different proteins (e.g., immunoglobulin G, bovine serum albumin, and horseradish peroxidase). To enable these studies, we developed a simple method to isolate quantum dot bioconjugates from unconjugated quantum dots. The results show that the reactant concentra ... | 2011 | 22101398 |
| fabrication of an electrochemical platform based on the self-assembly of graphene oxide-multiwall carbon nanotube nanocomposite and horseradish peroxidase: direct electrochemistry and electrocatalysis. | a novel hybrid nanomaterial (go-mwnts) was explored based on the self-assembly of multiwall carbon nanotubes (mwnts) and graphene oxide (go). compared with pristine mwnts, such a nanocomposite could be well dispersed in aqueous solution and exhibit a negative charge. driven by the electrostatic interaction, positively charged horseradish peroxidase (hrp) could then be immobilized onto go-mwnts at the surface of a glassy carbon (gc) electrode to form a hrp/go-mwnt/gc electrode under mild conditio ... | 2011 | 22101607 |
| Abdominal vagal afferent pathways and their distributions of intraganglionic laminar endings in the rat duodenum. | We examined abdominal vagal afferents (n = 33) and the distributions of their intraganglionic laminar endings (IGLEs) in the duodenum. Rats (male, Sprague-Dawley) received a partial subdiaphragmatic vagotomy that spared a single branch. Wheat germ agglutinin-horseradish peroxidase (0.5~1.0 µl) was injected into the nodose ganglion ipsilateral to the vagotomized side. We observed that: the hepatic branch does not project to the stomach, the accessory celiac and celiac branches course along the ce ... | 2011 | 22102316 |
| contact and fumigant toxicity of armoracia rusticana essential oil, allyl isothiocyanate and related compounds to dermatophagoides farinae. | background: the toxicity to adult dermatophagoides farinae of allyl isothiocyanate identified in horseradish, armoracia rusticana, oil and another 27 organic isothiocyanates was evaluated using contact + fumigant and vapour-phase mortality bioassays. results were compared with those of two conventional acaricides, benzyl benzoate and dibutyl phthalate. results: horseradish oil (24 h lc(50) , 1.54 µg cm(-2) ) and allyl isothiocyanate (2.52 µg cm(-2) ) were highly toxic. benzyl isothiocyanate (lc( ... | 2011 | 22102526 |
| Carbohydrate profiling of fungal cell wall surface glycoconjugates of Aspergillus species in brain and lung tissues using lectin histochemistry. | The aim of this study was to evaluate, through lectin histochemistry, the expression of N-acetyl-D-glucosamine, L-fucose, D-galactose and glucose/mannose on the cell wall surfaces of Aspergillus species in histopathological specimens of brain (n = 1) and lung (n = 6) tissues obtained during autopsy of patients diagnosed postmortem as having had invasive aspergillosis. Concanavalin A (Con A), wheat germ agglutinin (WGA), Ulex europeus agglutinin I (UEA-I) and peanut agglutinin (PNA), all conjugat ... | 2011 | 22103341 |
| gentiana asclepiadea and armoracia rusticana can modulate the adaptive response induced by zeocin in human lymphocytes. | zeocin is a member of bleomycin/phleomycin family of antibiotics isolated from streptomyces verticullus. this unique radiomimetic antibiotic is known to bind to dna and induce oxidative stress in different organisms producing predominantly single- and double- strand breaks, as well as a dna base loss resulting in apurinic/apyrimidinic (ap) sites. the aim of this study was to induce an adaptive response (ar) by zeocin in freshly isolated human lymphocytes from blood and to observe whether plant e ... | 2012 | 22103898 |
| Class II ADP-ribosylation Factors Are Required for Efficient Secretion of Dengue Viruses. | Identification and characterization of virus-host interactions are very important steps toward a better understanding of the molecular mechanisms responsible for disease progression and pathogenesis. To date, very few cellular factors involved in the life cycle of flaviviruses, which are important human pathogens, have been described. In this study, we demonstrate a crucial role for class II Arf proteins (Arf4 and Arf5) in the dengue flavivirus life cycle. We show that simultaneous depletion of ... | 2012 | 22105072 |
| characterization of g-quadruplex/hemin peroxidase: substrate specificity and inactivation kinetics. | recently, g-quadruplex/hemin (g4/hemin) complexes have been found to exhibit peroxidase activity, and this feature has been extensively exploited for colorimetric detection of various targets. to further understand and characterize this important dnazyme, its substrate specificity, inactivation mechanism, and kinetics have been examined by comparison with horseradish peroxidase (hrp). g4/hemin dnazyme exhibits broader substrate specificity and much higher inactivation rate than hrp because of th ... | 2011 | 22106035 |
| a proteomics approach to the cell-surface interactome using the enzyme-mediated activation of radical sources reaction. | we previously reported a simple method to analyze the interaction of cell-surface molecules in living cells. this method termed enzyme-mediated activation of radical sources (emars) is featured by radical formation of the labeling reagent by horseradish peroxidase (hrp). herein, we propose an approach to the cell-surface molecular interactome by using combination of this emars reaction and ms-based proteomics techniques. in the current study, we employed a novel labeling reagent, fluorescein-con ... | 2012 | 22106087 |
| Electrochemical detection of Pseudomonas aeruginosa 16S rRNA using a biosensor based on immobilized stem-loop structured probe. | We have designed an electrochemical DNA biosensor based on stem-loop structured probes for enzymatic detection of Pseudomonas aeruginosa 16S ribosomal RNA (rRNA) in composting degradation. The probe modified with a thiol at its 5' end and a biotin at its 3' end was immobilized on a gold electrode through self-assembly. The stem-loop structured probes were "closed" when target was absent, then the hybridization of the target induced the conformational changes to "open", along with the biotin at i ... | 2011 | 22112510 |
| reactive metabolites of desipramine and clomipramine: the kinetics of formation and reactivity with dna. | tricyclic antidepressants (tcas), along with phenothyazines and some industrial chemicals, are shown to react with enzymes that exhibit peroxidase activity. these reactions result in the formation of reactive intermediates having unpaired electrons. the peroxidase oxidation and reactivity of two tcas, desipramine and clomipramine, were investigated. as a model of peroxidase, horseradish peroxidase (hrp) was employed. the products of the peroxidase catalyzed oxidation of desipramine and clomipram ... | 2012 | 22115837 |
| fabrication of immunosensor microwell arrays from gold compact discs for detection of cancer biomarker proteins. | a simple method is reported to fabricate gold arrays featuring microwells surrounding 8-electrodes from gold compact discs (cds) for less than $0.2 per chip. integration of these disposable gold cd array chips with microfluidics provided inexpensive immunoarrays that were used to measure a cancer biomarker protein quickly at high sensitivity. the gold cd sensor arrays were fabricated using thermal transfer of laserjet toner from a computer-printed pattern followed by selective chemical etching. ... | 2012 | 22116194 |
| paracellular versus transcellular intestinal permeability to gliadin peptides in active celiac disease. | the intestinal permeability of undegraded α9-gliadin peptide 31-49 (p31-49) and 33-mer gliadin peptides is increased in active celiac disease. two distinct transport pathways have been proposed: paracellular leakage through epithelial tight junctions and protected transcellular transport. to analyze the relative contribution of these pathways, we compared mucosa-to-serosa permeability of small and large permeability markers [ionic conductance (g), mannitol, 182 da; horseradish peroxidase, 40 kda ... | 2012 | 22119716 |
| expression pattern of ck7 and ck20 in nasal polyps, at patients with chronic rhinosinusitis with nasal polyposis. | we investigated the expression of cytokeratins 7 (ck7) and 20 (ck20) in nasal polyps on a group of 106 patients with chronic rhinosinusitis with nasal polyposis (45 women - 42% and 61 men - 58%) who benefited from surgical procedures. harvested biological material was analyzed in the pathology laboratory through two methods: histopathological and immunohistochemical analysis. classical histopathological method of processing the tissues initially fixed in 10% formalin was used. the tissues were t ... | 2011 | 22119824 |
| immobilization of horseradish peroxidase onto a gold-nanoparticle-adsorbed poly(thionine) film for the construction of a hydrogen peroxide biosensor. | an amperometric hydrogen peroxide (h2o2) biosensor was developed based on the immobilization of horseradish peroxidase (hrp) onto a gold-nanoparticle (gnp)-adsorbed conducting poly(thionine) (pth) film. the modification process was characterized by scanning electron microscope (sem), electrochemical impedance spectroscopy (eis) and cyclic voltammetry (cv). the effects of experimental parameters such as the concentration of the mediator (hydroquinone, hq), the ph of the solution, and the working ... | 2011 | 22121589 |
| a protocol for in situ enzyme assays to assess the differentiation of human intestinal caco-2 cells. | the caco-2 cell line spontaneously differentiates into polarised enterocytes expressing high levels of brush border enzymes typical of small intestinal epithelial cells (peptidases, alkaline phosphatase, disaccharidases). the activities of these enzymes gradually increase after cell confluence reaching a plateau after 2-3weeks of culture and can be used as reliable markers to evaluate differentiation of caco-2 cells. we have developed a rapid in situ method on live cells to measure activities of ... | 2011 | 22123491 |
| toxic effects of a horseradish extract and allyl isothiocyanate in the urinary bladder after 13-week administration in drinking water to f344 rats. | subchronic toxicity of a horseradish extract (hre), consisting mainly of a mixture of allyl isothiocyanate (aitc) and other isothiocyanates, was investigated with administration at concentrations of 0, 0.0125, 0.025 and 0.05% of hre in drinking water for 13 weeks to male and female f344 rats. for comparison, treatment with 0.0425% of aitc was similarly performed. body weight gain was reduced in the 0.05% hre and aitc males as compared to the 0% controls, and the cause was considered at least par ... | 2011 | 22129740 |
| deletion of aquaporin-4 changes the perivascular glial protein scaffold without disrupting the brain endothelial barrier. | expression of the water channel aquaporin-4 (aqp4) at the blood-brain interface is dependent upon the dystrophin associated protein complex. here we investigated whether deletion of the aqp4 gene affects the molecular composition of this protein scaffold and the integrity of the blood-brain barrier. high-resolution immunogold cytochemistry revealed that perivascular expression of α-syntrophin was reduced by 60% in aqp4(-/-) mice. additionally, perivascular aqp4 expression was reduced by 88% in ... | 2011 | 22131281 |
| nano reengineering of horseradish peroxidase with dendritic macromolecules for stability enhancement. | a simple bio-conjugation procedure to surround a single horseradish peroxidase (hrp) enzyme molecule with dendritic polyester macromolecules (polyester-32-hydroxyl-1-carboxyl bis-mpa dendron, generation 5) was proposed. the characterization of resultant nanoparticles entitled hrp dendrozyme, was performed by transmission electron microscopy, dynamic light scattering, gel permeation chromatography and fourier transform infrared spectroscopy. the results showed that hrp nanoparticles were spherica ... | 2012 | 22133434 |
| global profiling of reactive oxygen and nitrogen species in biological systems: high-throughput real-time analyses. | herein we describe a high-throughput fluorescence and hplc-based methodology for global profiling of reactive oxygen and nitrogen species (ros/rns) in biological systems. the combined use of hplc and fluorescence detection is key to successful implementation and validation of this methodology. included here are methods to specifically detect and quantitate the products formed from interaction between the ros/rns species and the fluorogenic probes, as follows: superoxide using hydroethidine, pero ... | 2012 | 22139901 |
| ultrasensitive detection of phenolic compounds based on a spin-labeled luminescent lanthanide complex. | herein we propose a novel method for ultrasensitive detection of phenolic compounds. this method was developed based on a spin-labeled terbium complex tb(3+)/cs124-dtpa-tempo (1). this spin-labeled terbium complex is a weakly luminescent compound and shows strong off-on luminescent response to phenolic compounds in the presence of horseradish peroxidase (hrp), glutathione (gsh) and hydrogen peroxide. the analyte recognition and signaling mechanism are discussed and the factors affecting the off- ... | 2012 | 22140675 |
| highly sensitive photoelectronchemical immunoassay with enhanced amplification using horseradish peroxidase induced biocatalytic precipitation on a cds quantum dots multilayer electrode. | herein we demonstrate the protocol of biocatalytic precipitation (bcp)-based sandwich photoelectrochemical (pec) horseradish peroxidase (hrp)-linked immunoassay on the basis of their synergy effect for the ultrasensitive detection of mouse igg (antigen, ag) as a model protein. the hybrid film consisting of oppositely charged polyelectrolytes and cds quantum dots (qds) is developed by the classic layer by layer (lbl) method and then employed as the photoactive antibody (ab) immobilization matrix ... | 2011 | 22148581 |
| enzyme reactions in nanoporous, picoliter volume containers. | advancements in nanoscale fabrication allow creation of small-volume reaction containers that can facilitate the screening and characterization of enzymes. a porous, ∼19 pl volume vessel has been used in this work to carry out enzyme reactions under varying substrate concentrations. assessment of small-molecule and green fluorescent protein diffusion from the vessels indicates that pore sizes on the order of 10 nm can be obtained, allowing capture of proteins and diffusive exchange of small mole ... | 2012 | 22148720 |
| biodegradation and in vitro biocompatibility of polyperoxides: alternating co-polymers of vinyl monomers and molecular oxygen. | vinyl polyperoxides, alternating co-polymers of vinyl monomers and molecular oxygen, are a small but important class of polymers with unique properties, such as highly exothermic degradation in contrast to common polymers, which generally show endothermic degradation. enzymatic degradation and in vitro biocompatibility have been studied for the vinyl polyperoxides polystyrene peroxide (psp), poly(α- methylstyrene) peroxide (pamsp) and poly(methyl methacrylate) peroxide (pmmap). enzymatic degrada ... | 2012 | 22152546 |
| nanogold-functionalized magnetic beads with redox activity for sensitive electrochemical immunoassay of thyroid-stimulating hormone. | a new electrochemical immunosensor for sensitive determination of thyroid-stimulating hormone (tsh) was designed by using redox-active nanogold-functionalized magnetic beads (goldmag) as signal tags on the nanogold-graphene interface. to construct such goldmag nanostructures, polyethyleneimine-functionalized magnetic beads (pei-mbs) were initially prepared by using a wet chemical method, and the electroactive thionine molecules and gold nanoparticles were then alternately immobilized on the surf ... | 2012 | 22152790 |