| ganglion cell types of the turtle retina that project to the optic tectum: intracellular hrp injections of retrogradely, rhodamine-marked cell bodies. | the turtle retina has been shown to have a variety of different morphological ganglion cell types as well as distinct physiological ganglion cell types. the major projection of the retina to the brain in nonmammalian vertebrates is to the optic tectum. in this study, we address the question of which retinal ganglion cell types project to the optic tectum in the turtle. fluorescent rhodamine-labeled microspheres were used to trace the retinal ganglion cell projection to the superficial layers of ... | 1992 | 1562567 |
| effect of antioxidants on chemiluminescence produced by reactive oxygen species. | luminol chemiluminescence was used to evaluate the scavenging of superoxide, hydroxyl and alkoxy radicals by four antioxidants: dipyridamole, diethyldithiocarbamic acid, (+)catechin, and ascorbic acid. different concentrations of these compounds were compared with well-known oxygen radical scavengers in their capacity to inhibit the chemiluminescence produced in the reaction between luminol and specific oxygen radicals. hydroxyl radicals were generated using the fenton reaction and these produce ... | 1992 | 1317990 |
| stress-induced alterations in autophagic pathway: relationship to ubiquitin system. | the autophagic response of the cell to nutrient deprivation or heat stress is characterized by an increase in the rate of cellular protein degradation. using temperature-sensitive mutant cell lines that harbor a mutation in the ubiquitin pathway, we have recently shown that this response is dependent on a functional ubiquitin-activating enzyme e1. the ubiquitin pathway is involved in a multitude of cellular events including protein degradation, the best understood of these. herein the activation ... | 1992 | 1314483 |
| peroxidase oxidizes n-nitrosomethylaniline to ultimate carcinogens(s) binding to dna and transfer rna in vitro. | carcinogenic n-nitrosomethylaniline is oxidized in vitro by horseradish peroxidase in the presence of h2o2 to ultimate carcinogens, which bind to dna and transfer rna (trna). trna is more accessible for modification by the activated carcinogen studied. the modification of nucleic acid by n-nitrosomethylaniline metabolite(s) formed by peroxidase is inhibited by some compounds of physiological importance (ascorbate, glutathine) and by radical trapping agents (nitrosobenzene, methyl viologen). 32p- ... | 1992 | 1313333 |
| how do organic solvents affect peroxidase structure and function? | the effect of organic solvents on horseradish peroxidase structure and function has been studied. some, but not complete, enzyme denaturation occurs even in low volumes of water-miscible organic solvents (e.g., greater than 30% v/v dioxane, greater than 50% v/v methanol, and greater than 20% v/v acetonitrile) as determined by the decreased difference between the fluorescence of peroxidase's sole tryptophan residue and free l-tryptophan in solution. absorbance and electron paramagnetic resonance ... | 1992 | 1312352 |
| evidence for a driving role of ingrowing axons for the shifting of older retinal terminals in the tectum of fish. | in amphibians and teleosts, retina and tectum grow incongruently. in order to maintain the retinotopy of the retinotectal projection, gaze, keating, and chung (1974) postulated a shifting of terminals throughout growth. in order to test the possibility that ingrowing retinal fibers are the driving force for this shifting, we induced a permanent retinal projection into the ipsilateral tectum in juveniles of the cichlid fish haplochromis burtoni. the surface of the tectum had increased (11-18 mont ... | 1992 | 1527525 |
| [a morphological study of pulmonary macrophages in bleomycin-injected murine models]. | pulmonary changes induced in a murine model by intraperitoneal injections of bleomycin were morphologically studied by light and electron microscopy. the number of pulmonary macrophages and the distribution of fibronectin in these cells were evaluated by acid phosphatase and affinity staining using anti-fibronectin horseradish peroxidase conjugates. the onset of acute inflammation occurred 4 days after intraperitoneal injection of bleomycin and reached its peak on the 14th day post-injection. th ... | 1992 | 1373783 |
| new screening system for simultaneous determination of two marker proteins by homogeneous enzyme immunoassay. | to save time and labour in mass screening, by detecting two marker proteins on one specimen using only one test. | 1992 | 1372918 |
| evaluation of the probe 2',7'-dichlorofluorescin as an indicator of reactive oxygen species formation and oxidative stress. | the use of dichlorofluorescin (dcfh) as a measure of reactive oxygen species was studied in aqueous media. hydrogen peroxide oxidized dcfh to fluorescent dichlorofluorescein (dcf), and the oxidation was amplified by the addition of ferrous iron. hydrogen peroxide-induced dcf formation in the presence of ferrous iron was completely inhibited by deferoxamine and partially inhibited by ethylenediaminetetraacetic acid, but was augmented by diethylenetriaminepentaacetic acid. iron-peroxide-induced ox ... | 2016 | 1322737 |
| regulated endocytosis in a chloride secretory epithelial cell line. | the colonic epithelial cell line t84 has been shown to be a good model to investigate the regulation of cl- secretion by the adenosine 3',5'-cyclic monophosphate (camp)-mediated second messenger cascade. regulated exocytic insertion and endocytic retrieval of transport proteins, or proteins that regulate transport proteins, is one mechanism proposed to regulate plasma membrane solute permeabilities. the aims of our studies were to characterize endocytic processes in t84 cells and to investigate ... | 1992 | 1312784 |
| [the demonstration of recurrent motor axon collaterals in the chick embryo by using horseradish peroxidase axonal transport]. | motoneurons were labelled by retrograde axonal transport of hrp applied to transected spinal nerves in 9-11-day chick embryos in the in vitro spinal cord preparation. recurrent motor axon collaterals were revealed in 17 of 48 motor axons which could be followed in the edge regions of labelled motoneuronal pools. the results, coupled with author's earlier electrophysiological data, provide further evidence for the presence of the renshaw inhibition in the avian spinal cord. | 2006 | 1280893 |
| organic solvents strip water off enzymes. | exchange of enzyme-bound h(2)o with t(2)o in aqueous solution followed by freeze drying provided tritiated water bound to chymotrypsin, subtilisin carlsberg, and horseradish peroxidase. the desorption of t(2)o from these enzymes suspended in various organic solvents showed that all three enzymes lost enzyme-bound water with peroxidase losing the most t(2)o of the three in solvents of moderate to high polarity. polar solvent resulted in the highest degree of t(2)o desorption (e.g., methanol desor ... | 1992 | 18600960 |
| on the use of iron octa-alkylporphyrins as models for protoporphyrin ix-containing heme systems in studies employing magnetic circular dichroism spectroscopy. | the magnetic circular dichroism (mcd) properties of numerous oxidation and ligation state derivatives of myoglobin and horseradish peroxidase reconstituted with an iron octa-alkylporphyrin (mesoheme ix) have been investigated in order to establish the utility of such porphyrins as models for protoporphyrin ix-containing systems. the mcd spectra of the mesoheme-reconstituted proteins are blue-shifted (4-12 nm) and are somewhat more intense (1.5-2.5 fold) when compared to the spectra of analogous ... | 1992 | 1634892 |
| a competitive elisa for lipoprotein(a). | a competitive elisa for lipoprotein(a) (lp(a)) is described. the method uses a commercially available polyclonal anti-lp(a) antibody and an igg biotinstreptavidin-horseradish peroxidase detection system. the method is simple and robust with an assay sensitivity of 0.7 ng/well (1.4 micrograms/l). the antibody cross-reactivity was 0.14% against ldl and 0.70% against plasminogen. the coefficients of variation obtained with control sera of 266 and 552 mg/l were: 5.0% and 4.6% (n = 6), respectively f ... | 1992 | 1533578 |
| claustrum in the hedgehog (erinaceus europaeus) brain: cytoarchitecture and connections with cortical and subcortical structures. | the cytoarchitecture of the claustrum in the hedgehog (erinaceus europaeus) brain, the morphology of its neurons, and the efferent connections with cortical and subcortical structures were studied with the nissl and klüver-barrera, the golgi, and the horseradish peroxidase methods. it was found that the claustrum is a well developed nucleus in the hedgehog telencephalon and, as in other mammals, is divided into dorsal and ventral parts. in golgi-stained sections, spiny multipolar cells are the p ... | 1992 | 1374084 |
| endosomal system of paramecium: coated pits to early endosomes. | a detailed morphological and tracer study of endocytosis via coated pits in paramecium multimicronucleatum was undertaken to compare endocytic processes in a free-living protozoon with similar processes in higher organisms. permanent pits at the cell surface enlarge, become coated and give rise to coated vesicles (188 +/- 41 nm in diameter) that enclose fluid-phase markers such as horseradish peroxidase (hrp). both the pits and vesicles are labeled by the immunogold technique when a monoclonal a ... | 1992 | 1629255 |
| effect of serum ph on bilirubin-protein binding. | progressive increase of the serum ph upon standing and storage in different conditions is documented. bilirubin albumin titration studies were performed on serum of different ph by sephadex gel filtration and horseradish peroxidase oxidation methods. results showed that different ph produced different titration curves and that more reproducible and consistent results were obtained with the peroxidase oxidation titration method. addition of hcl and co2 to the serum also produced different bilirub ... | 1992 | 1580149 |
| projections from the lateral nucleus of the trapezoid body to the medial superior olivary nucleus in the gerbil. | we made small injections of horseradish peroxidase into the medial superior olivary nucleus (mso) of gerbils in order to examine the sources of input into that nucleus. as previously described, the mso receives inputs from neurons in the rostral part of both anteroventral cochlear nuclei. in addition, we found evidence for a projection from the ipsilateral lateral nucleus of the trapezoid body (lntb). our results are also compatible with previous reports that the medical nucleus of the trapezoid ... | 1992 | 1559903 |
| reagentless enzyme electrode for the determination of manganese through biocatalytic enhancement. | an amperometric enzyme electrode is described for the detection and determination of manganese(ii). the biosensor is based on the stimulation by manganese of the aerobic oxidation of substrates by horseradish peroxidase. a mediator, 1,2-naphthoquinone, is used as the substrate and is incorporated with the enzyme into a carbon-paste electrode. the resulting electrode acts as an enzyme-based oxygen sensor, which is sensitive to manganese. electrochemical control of enzyme activity is achieved thro ... | 1992 | 1554095 |
| more than two pyrrole tautomers of mesoporphyrin stabilized by a protein. high resolution optical spectroscopic study. | mesoporphyrin ix substituted horseradish peroxidase was studied by fluorescence line narrowing and hole burning techniques at cryogenic temperatures. the spectral data reveal that four pyrrole tautomeric configurations of the chromophore are populated within the protein under the influence of irradiation and/or thermal treatment, and the existence of a fifth and a sixth tautomeric configuration is also likely. the relative population of the tautomers changes upon deuterium substitution through m ... | 1992 | 1547326 |
| chemiexcitation in the peroxidative metabolism of diethylstilbestrol. | when the synthetic estrogen and tumourogenic compound diethylstilbestrol is exposed to horseradish peroxidase (hrp) and h2o2 in the presence of the cationic surfactant hexadecyltrimethylammonium bromide (ctab), a burst of oxygen consumption and concomitant light emission are observed. the quinone form of the product is not seen in the absorption spectrum because ctab strongly catalyses its conversion to z,z-dienestrol. the emission spectrum shows several peaks. total emission is dramatically enh ... | 1992 | 1542709 |
| chemiexcitation in the peroxidative metabolism of diethylstilbestrol. metabolic products. | in the presence of the surfactant hexadecyltrimethyl ammonium bromide (ctab) a cascade of electronically excited states accompanies the successive steps in the peroxidative metabolization of the strong estrogenic and tumourogenic diethylstilbestrol. reversing the order by necessity, we report in this first paper results with the metabolites. exposure of 4-hydroxypropiophenone, z,z-dienestrol or e,e-dienestrol to horseradish peroxidase and h2o2 promotes oxygen uptake and spectral alterations. lig ... | 1992 | 1542708 |
| comparison of penicillinase with horseradish peroxidase as enzyme tracer in elisa for the toxin cleistanthin b. | | 2006 | 1428990 |
| competitive binding assay for quantitative determination of gm1 ganglioside in plasma and cerebrospinal fluid. | a competitive binding assay for the quantitative determination of gm1 ganglioside is described. after extraction from biological fluids, gm1 was incubated with a known amount of cholera toxin b-subunit conjugated with horseradish peroxidase, and exposed to gm1 adsorbed onto polystyrene microwells. since gm1 in solution blocks the binding of toxin b-subunit to gm1 adsorbed onto the solid phase, enzyme activity serves as a reciprocal measure of gm1 concentration in the sample. the assay was used t ... | 2004 | 1391096 |
| structural and functional consequences of neonatal deafferentation in the superficial layers of the hamster's superior colliculus. | intracellular recording and horseradish peroxidase (hrp) injection techniques were used to evaluate the effects of neonatal enucleation upon the structural and functional properties of cells in the superficial retinorecipient laminae of the hamster's superior colliculus (sc). the physiological recordings confirmed previous results that normally visual superficial layer neurons develop somatosensory receptive fields in the enucleated animals. this study further showed that all of the physiologica ... | 1992 | 1560114 |
| a second auditory area in the non-cortical telencephalon of a reptile. | injections of horseradish peroxidase (hrp) into a caudocentral portion of the non-cortical telencephalon of caiman known as the dorsolateral area (dorsal ventricular ridge) resulted in retrogradely labeled neurons throughout the entire extent of the ipsilateral nucleus reuniens. hrp-positive cells were most numerous in nucleus reuniens pars diffusa with only sparse labeling of neurons in nucleus reuniens pars centralis. the results of the present experiment, when compared with those of a prior s ... | 1992 | 1377079 |
| mechanisms of cytochrome p450 and peroxidase-catalyzed xenobiotic metabolism. | the cytochrome p450 enzyme systems catalyze the metabolism of a wide variety of naturally occurring and foreign compounds by reactions requiring nadph and o2. cytochrome p450 also catalyzes peroxide-dependent hydroxylation of substrates in the absence of nadph and o2. peroxidases such as chloroperoxidase and horseradish peroxidase catalyze peroxide-dependent reactions similar to those catalyzed by cytochrome p450. the kinetic and chemical mechanisms of the nadph and o2-supported dealkylation rea ... | 1992 | 1537457 |
| the somatotopic organization within the cat's thalamic reticular nucleus. | the organization of the somatosensory representation within the cat's thalamic reticular nucleus (trn) was studied. focal injections of horseradish peroxidase (hrp), wheatgerm agglutinin conjugated to hrp, and/or [3h]proline were made into somatosensory cortical areas 1 (s1) and 2 (s2). the resultant labelling in the thalamus was analysed. single injections into s1 result in single zones of terminal labelling in trn that are restricted to the centroventral part of the sheet-like nucleus. in reco ... | 1992 | 12106398 |
| the somatotopic organization within the rabbit's thalamic reticular nucleus. | the organization of the somatosensory representation within the rabbit's thalamic reticular nucleus (trn) was studied. focal injections of horseradish peroxidase (hrp), wheatgerm agglutinin conjugated to hrp, or [3h]proline were made into somatosensory cortical area 1 (s1). the resultant labelling in the thalamus was analysed. single injections into s1 result in single zones of terminal labelling in trn that are restricted to the centroventral part of the sheet-like nucleus. in reconstructions f ... | 1992 | 12106397 |
| restoration of conduction and growth of axons through injured spinal cord of neonatal opossum in culture. | the ability of neurons in the central nervous system to grow through a lesion and restore conduction has been analyzed in a developing spinal cord. the preparation consists of the entire central nervous system of the newly born opossum (monodelphis domestica), isolated and maintained in culture. cell division, cell migration, and reflexes are maintained in such preparations for up to 8 days in culture. in the present experiments, massive lesions were produced by crushing the spinal cord, which a ... | 1992 | 1729714 |
| direct retinal projections of the "non-image forming" system to the hypothalamus, anterodorsal thalamus and basal telencephalon of mink (mustela vison) brain. | the retinal projections of the "non-image forming" system to the hypothalamus, anterodorsal thalamus and basal telencephalon were visualized in adult mink using the anterograde transport of cholera toxin conjugated to horseradish peroxidase injected intraocularly. a major and nearly symmetrical bilateral input of labeled retinal fibers to the suprachiasmatic nuclei was observed. a dense innervation was also evident in both paraventricular nuclei, and in the anterior, lateral and mediobasal hypot ... | 1992 | 1623980 |
| displaced retinal ganglion cells in normal frogs and those with regenerated optic nerves. | we have analysed the number and spatial distribution of displaced retinal ganglion cells in the frog litoria (hyla) moorei. a series of normal animals was compared with one in which the optic nerve was crushed and allowed to regenerate. ganglion cells were labelled with horseradish peroxidase (hrp) applied to the optic nerve, and retinae were examined as sections or whole mounts. we analysed separately ganglion cells with somata displaced to the inner nuclear (dogiel cells, dgcs) and to the inne ... | 1992 | 1567019 |
| wulst efferents in the little owl athene noctua: an investigation of projections to the optic tectum. | the efferent projections from the wulst were studied in the little owl, athene noctua, using anterograde migration of wheat-germ-agglutinin conjugated horseradish peroxidase (wga-hrp). wulst projections were distributed to telencephalic, diencephalic and mesencephalic targets in a general pattern similar to that previously described in other avian species. our results on the organization of the wulst-optic tectum pathway in the little owl reveal well defined and laminarly arranged terminal proje ... | 1992 | 1555108 |
| oxidative metabolism of polymorphonuclear leukocytes (pmn) in patients with iga nephropathy. | the production of hydrogen peroxide (h2o2) by neutrophilic polymorphonuclear leukocytes (pmn) after stimulation and the infiltration of pmn in glomeruli were determined in 20 patients with primary iga nephropathy. the h2o2 production of pmn after the stimulation was measured with a spectrophotometer using horseradish peroxidase as substrate. the results were as follows: 1) when pmn were pretreated with cytochalasin b, h2o2 production after stimulation with heat-aggregated igg (igg) or serum-trea ... | 1992 | 1542082 |
| a morphological study of abducens nucleus motoneurons and internuclear neurons in the goldfish (carassius auratus). | the location and distribution of abducens (abd) nucleus motoneurons (mn) and internuclear neurons (int) were determined in the goldfish (carassius auratus) by means of horseradish peroxidase and fluorochrome retrograde labeling. abd mn were labeled following tracer injection into the ipsilateral lateral rectus muscle. these mn were arranged in two ventrolateral clusters along the rostro-caudal axis of the posterior brainstem. both groups of neurons showed a similar number of cells, and their axo ... | 1992 | 1540841 |
| localization of pectoral fin motoneurons (sonic and hovering) in the croaking gourami trichopsis vittatus. | the pectoral fin of the croaking gourami, trichopsis vittatus, has become modified as a sound-producing organ and retains its original function in locomotion and hovering. we used retrograde transport of horseradish peroxidase to localize sonic motoneurons in trichopsis. betta splendens, a related nonsonic gourami with unspecialized pectoral fins, served as a control. a single injection into trichopsis epaxial muscle labeled a dorsal motor column of large cells (mean of 16.3 microns) ventrolater ... | 1992 | 1537046 |
| [the study of dna fingerprint using probe directly labelled with horseradish peroxidase and enhanced chemiluminescence in forensic science application]. | we describe here the technique of dna probe directly labelled with horseradish peroxidase (hrp) and enhanced chemiluminescence (ecl) detection for determining dna fingerprints. the patterns of dna fingerprint were clear and with high distinction. the sensitivity of dna fingerprint was 0.8 microgram, similar to the method of 32p labelling. the dna fingerprints of 150 unrelated individuals were studied and showed that the probability of chance association of dna fragments between random individual ... | 1992 | 1524850 |
| comparison of colloidal gold electrode fabrication methods: the preparation of a horseradish peroxidase enzyme electrode. | in order to prepare biosensing electrodes which respond to hydrogen peroxide, horseradish peroxidase has been adsorbed to colloidal gold sols and electrodes prepared by deposition of these enzyme-gold sols onto glassy carbon using three methods: evaporation, electrodeposition and electrolyte deposition. in the latter method the enzyme-gold sol is applied to the surface of a glassy carbon disk electrode followed by an equal volume of 2 mm cacl2. the electrolyte causes the sol to precipitate on th ... | 1992 | 1515118 |
| the pattern of trunk lateral line afferents and efferents in the rainbow trout (salmo gairdneri). | the primary projections of the mechanosensory posterior lateral line nerve of the rainbow trout salmo gairdneri, a teleost without lateral line specializations, were studied by applying horseradish peroxidase (hrp). the afferents project nearly exclusively to the nucleus medialis and a small nucleus caudalis in the hindbrain, and to the eminentia granularis. in addition, there is a sparse projection to the cerebellum, but a projection to the magnocellular nucleus is lacking. the afferent project ... | 1992 | 1498657 |
| afferent connections of the habenular complex in the lizard gallotia galloti. | afferents to the habenular complex were studied by means of in vitro horseradish peroxidase retrograde labeling and anterograde control experiments in the lizard gallotia galloti. the medial habenular nucleus was found to receive abundant afferent fibers from the nucleus of the posterior pallial commissure and the nucleus septalis impar. more restricted input comes from the nucleus eminentiae thalami and the nucleus of the stria medullaris. the lateral habenular nucleus is innervated by various ... | 1992 | 1498653 |
| anatomical pathways from the optic tectum to the spinal cord subserving orienting movements in the barn owl. | electrical stimulation of the optic tectum in many vertebrate species elicits eye, head or body orienting movements in the direction of the receptive field location recorded at the site of stimulation; in the barn owl, tectal stimulation produces short latency saccadic head movements (du lac and knudsen 1990). however, the barn owl, like other avians, lacks a direct projection from the tectum to the spinal cord, implying that less direct connections underlie tectally mediated head movements. in ... | 1992 | 1493861 |
| retinal projections in the house musk shrew, suncus murinus, as determined by anterograde transport of wga-hrp. | retinal projections in the house musk shrew (suncus murinus) were determined by the anterograde transport of wheat germ agglutinin conjugated to horseradish peroxidase (wga-hrp). unilateral injection of wga-hrp into the vitreous body resulted in the terminal labeling of the optic projections in the suprachiasmatic nucleus (sch), the ventral (cglv) and dorsal (cgld) lateral geniculate nuclei, the intergeniculate leaflet (igl), the pretectum, the superficial layers of the superior colliculus (cs), ... | 1992 | 1472991 |
| the red nucleus and mesencephalic tegmentum in a ranid amphibian: a cytoarchitectonic and hrp connectional study. | movement control in vertebrates is a complex function that is known to involve several parallel systems. in amphibians, which lack the isocortical structures shown in mammals to initiate and control voluntary movements, supraspinal motor control systems have received surprisingly little attention. because amphibians lack a corticospinal equivalent, coordination and control of all movement strategies must take place in non-cortical, supraspinal integrating centers. the rubro-cerebello-rubrospinal ... | 1992 | 1472987 |
| changes in retinal projections and ganglion cell morphology after unilateral enucleation in the common carp. | changes in retinal projections and ganglion cell morphology were studied in one-eyed individuals of the common carp, cyprinus carpio, which were enucleated at a juvenile stage (within 6 months after hatching) and kept for 18 months after the operation. gross examination of the brains showed a marked atrophy of the contralateral optic tectum and a fine attenuated optic tract ipsilateral to the remaining eye. all retinal recipient areas were bilateral, but numerous projections were heavier contral ... | 1992 | 1450895 |
| primary projections of the lateral line nerves in larval sea lamprey, petromyzon marinus l. an hrp study. | the primary central projections of the anterior and posterior lateral line nerves were determined in the larval sea lamprey, petromyzon marinus l. using silver staining methods and axonal transport of horseradish peroxidase (hrp). lateral line fibers course in the dorsal portion of the octavolateral area. at the level of their entry in the medulla, all the lateral line fibers originate ascending and descending branches. the anterior lateral line nerve consists of three roots: dorsal, intermediat ... | 1992 | 1447520 |
| [immunoglobulin filtration and reabsorption as possible factors in the pathogenesis of chronic glomerulonephritis. clinical, immunomorphological and histoenzymological research]. | kidney biopsy specimens obtained from a group of individuals with chronic glomerulonephritis (cgn) have been processed for light and electron microscopic immunolocalization of total immunoglobulins (igs). in a few cases, acid phosphatase (acpase), a lysosomal enzyme marker, was ultrastructurally visualized. in the glomeruli, horseradish peroxidase-stained igs were revealed in capillary lumina, urinary spaces and in transit through occasional loci of the glomerular basal membranes while acpase-co ... | 1992 | 1440330 |
| an enzymatic determination of hydrogen peroxide by using spectrophotometry. | a new spectrophotometric method for determining low hydrogen peroxide concentrations by using horseradish peroxidase in the presence of nadh at ph 7.5 has been described. both total nadh consumption and initial reaction rate may be used for the determination. using the nadh consumption, a linear response with respect to hydrogen peroxide was observed in the concentration range 7 x 10(-8)-2.5 x 10(-6) m. due to the presence of superoxide dismutase, hydrogen peroxide is partly regenerated and an a ... | 1992 | 1422921 |
| distribution of cortical neurons projecting to dorsal column nuclear complex and spinal cord in the hedgehog tenrec, echinops telfairi. | using retrograde axonal flow and wheatgerm agglutinin conjugated to horseradish peroxidase, we studied the distribution of cortical neurons giving rise to spinal and dorsal column nuclear projections, and correlated the regions involved in the projections with the cytoarchitectonic areas recently identified in the lesser hedgehog tenrec, echinops telfairi (insectivora). labeled cortical neurons were most numerous following injections of tracer into higher cervical segments, whereas almost none w ... | 1992 | 1414117 |
| afferent and efferent connections of the bullfrog medial pallium. | horseradish peroxidase or tritiated proline was unilaterally injected into the medial pallium in bullfrogs in order to determine the sources of afferent projections to the medial pallium and the targets of pallial efferent projections. some cells in all telencephalic centers, except the corpus striatum and the pars lateralis of the amygdala, project to the ipsilateral medial pallium. the medial pallium receives projections from fewer centers in the contralateral hemisphere, which include the med ... | 1992 | 1393516 |
| disconnected optic axons persist in the visual pathway during regeneration of the retino-tectal projection in the frog. | in this study, we crushed one optic nerve in the frog litoria (hyla) moorei and at intervals thereafter anterogradely labelled optic axons with horseradish peroxidase (hrp). for one series, hrp was applied between the eye and the crush site and in a second series between the crush site and the chiasm. a tectal projection of regenerating axons was seen in both series but, in addition, up to 12 weeks post-crush, the second series displayed an additional projection. its appearance matched that of t ... | 1992 | 1385202 |
| identification of spinal electromotoneurons in the ray raja clavata (rajidae). | retrograde transport of horseradish peroxidase injected ipsilaterally in several parts of the electric organ and light microscopy were employed to study motoneurons and electromotoneurons of the spinal cord in the weakly electric ray raja clavata (rajidae). the horseradish peroxidase-labelled electromotoneurons form a chain of cells located ventrolaterally in the gray matter of the spinal cord segments adjacent to the electric organ. the diameters of cells in the electromotor nucleus vary from 7 ... | 1992 | 1376452 |
| the bilateral bulbar projections of the primary olfactory neurons in the frog. | whether or not the frog olfactory neuroreceptor cells project bilaterally to the olfactory bulb is still a debated question. we therefore decided to ascertain whether bilateral projections of the primary olfactory input exist and if so to investigate their extent. reproducible extracellular bilateral bulbar potentials were recorded in the frog following electrical stimulation of dorsal or ventral olfactory nerve bundles. the general features of the contralateral evoked responses were very simila ... | 1992 | 1376279 |
| an explanation of the achromatic bands produced by peroxidase isozymes in polyacrylamide electrophoresis gels stained for malate dehydrogenase. | when plant tissue extracts are electrophoresed on polyacrylamide gels and the gels are stained for malate dehydrogenase by the standard nad-dependent dehydrogenase reaction, terminating in the formation of reduced nitroblue tetrazolium (nbt), achromatic bands, in addition to the expected chromatic bands, are observed. the achromatic bands are seen when the staining conditions favor a generalized background staining of the gel and have been shown, in a previous study, to be caused by peroxidase i ... | 2013 | 1375153 |
| interconnections between the primate cerebellum and midbrain near-response regions. | the goal of this study was to determine the pattern of the connections between the midbrain and cerebellum that may play a role in the modulation of the near-response in the macaque. injection of the retrograde tracer wheat germ agglutinin conjugated horseradish peroxidase (wga-hrp) into the physiologically identified midbrain near-response region, which includes the supraoculomotor area, labelled cells throughout the deep cerebellar nuclei. however, labelled cells were particularly concentrated ... | 1992 | 1371782 |
| distribution of the blood-brain barrier in heterotopic brain transplants and its relationship to the lesions of eae. | the blood-brain barrier (bbb) is recognized as a barrier to the trafficking of molecules and cellular elements into the central nervous system (cns). horseradish peroxidase (hrp) exclusion is used as a measure of bbb integrity. the bbb is altered and becomes permeable during the course of experimental allergic encephalomyelitis (eae). heterotopic brain transplantation into the anterior eye chamber is a technique for studying genetic influences and the role of individual cell types on the develop ... | 1992 | 1371310 |
| regeneration of the eighth cranial nerve in the bullfrog, rana catesbeiana. | the present study was done in order to document the ability of the eighth cranial nerve of the bullfrog (rana catesbeiana) to regenerate, the anatomic characteristics of the regenerated fibers, and the specificity of projections from individual endorgan branches of the nerve. the eighth cranial nerve was sharply transected between the ganglion cells and the brain stem in 40 healthy bullfrogs and allowed to regenerate. anatomic studies were performed in these animals a minimum of 3 months postope ... | 1992 | 1370219 |
| maximal .oh production is seen upon reoxygenation of viable anoxic cultured cardiomyocytes but not of compromised cells. | hydroxyl radicals (.oh) in isolated cultured cardiomyocytes upon reoxygenation (reoxy) were measured after graded anoxia (a) using high performance liquid chromatography (hplc). isolated myocytes were subjected to a for 15, 30, 60, 90 and 120 minutes and reoxy for 120 seconds. supernatant was collected after reoxy, extracted with ether and injected into hplc for measuring hydroxylation products of salicylic acid (2,5-dhba) as an indicator of .oh formation. 2,5-dhba was detected maximally after 1 ... | 1992 | 1338485 |
| cholinergic, monoaminergic and peptidergic innervation of the primary visual centers in the brain of the lizards gekko gecko and gallotia galloti. | in order to study the relationship between retinal projections and immunohistochemically identified neurotransmitter systems in the primary visual centers of the brain in lizards, intraocular injections of horseradish peroxidase were combined with immunohistochemistry. antibodies raised against six substances were applied: choline acetyltransferase (chat), serotonin (5-ht), tyrosine hydroxylase (th), dopamine (da), substance p (sp), and leu-enkephalin (lenk). in the primary visual centers of the ... | 1992 | 1280514 |
| pattern of retinotectal projection in the megachiropteran bat rousettus aegyptiacus. | the retinotopic organisation of the superior colliculus (sc) in the megachiropteran bat rousettus aegyptiacus was examined with single and multi-unit recordings and by tracing the retrograde and anterograde transport of horseradish peroxidase (hrp) between the retina and the sc. the pattern of projection of the visual field onto the sc in rousettus resembles the pattern found in most mammals. the whole of the contralateral visual field is represented and, in addition, a region of the ipsilateral ... | 1991 | 1816270 |
| peripheral and central aspects of the acoustic and lateral line system of a bottom dwelling catfish, ancistrus sp. | the topographical relationship between the swim bladder, the inner ear, and the otic lateral line was studied in the bottom dwelling catfish, ancistrus sp. in addition, afferent and efferent subcomponents of the eighth and lateral line nerves were labelled with horseradish peroxidase (hrp) or with differently fluorescing dextran amines. the swim bladder of ancistrus consists of two separate, transversely oriented parts of each of which is connected to the sinus impar of the inner ears via two we ... | 1991 | 1726106 |
| 1h-nmr characterization of cucumber peroxidases. | two peroxidase isoenzymes from cucumber seedlings, one acidic (pi = 4) and one basic (pi = 9), were characterized by 1h-nmr spectroscopy. the nmr spectra were obtained in the native (ferric high-spin) and cyanide ligated (ferric low-spin) forms of both isoenzymes. the nmr spectral comparison of paramagnetically shifted resonances with those of the well characterized horseradish peroxidase c, hrp(c), isoenzyme indicates that both cucumber peroxidases have a protohemin ix prosthetic group with pro ... | 1991 | 1764475 |
| evaluation of antigen-antibody affinity constants by partition equilibrium studies with a two-phase aqueous polymer system: a more rigorous analysis. | a quantitative procedure is devised for the determination of affinity constants from the composition-dependence of the antigen partition coefficient in liquid-liquid partition studies of antigen-antibody mixtures. its use is illustrated by application to published results (elling, l.r., kula, m.-r., hadas, e. and katchalski-katzir, e. (1991) anal. biochem. 192, 74-77) obtained for the interaction of horseradish peroxidase with an elicited monoclonal antibody by antigen distribution studies with ... | 1991 | 1764465 |
| enhanced chemiluminescence for the detection of membrane-bound nucleic acid sequences: advantages of the amersham system. | a range of nonradioactive nucleic acid labeling and detection systems have been developed that enable the user to label probes directly with enzyme molecules or indirectly with hapten-derivatized nucleotides. horseradish peroxidase is used for the direct labeling procedures due to the ease of chemical modification and the relative thermal and chemical stability of this enzyme. horseradish peroxidase has also been conjugated to a high-specificity antifluorescein antibody for detection of hapten ( ... | 1991 | 1817575 |
| the distribution of uterine macrophages in virgin and early pregnant mice. | the spatiotemporal distribution of macrophages in the uterine wall of virgin mice and mice in the first half of pregnancy has been studied. macrophages were identified using a combination of morphological criteria, the capacity to endocytose horseradish peroxidase and the expression of the mac-1 antigen. in virgin mice and mice at preimplantation stages of pregnancy, macrophages were found throughout the endometrium, myometrium and mesometrial triangle. following implantation, and in parallel wi ... | 1991 | 1817136 |
| development of antibody-forming cells in follicles of lymph nodes of mice after continuous antigenic stimulation. | it was the purpose of the present study to test a hypothesis on the direct differentiation of newly formed memory b cells into antibody-forming cells (afc) in the follicles of lymph nodes. afc may develop in follicles when mobile antigen is present at the moment that such memory b cells have completed their differentiation under influence of immune complexes trapped on follicular dendritic cells (fdc). in order to study whether the simultaneous presence of mobile antigen and immobilized immune c ... | 1991 | 1800313 |
| estimation of cellulase activity using a glucose-oxidase-cu(ii) reducing assay for glucose. | in the presence of the cu(i)-chelating agent neocuproine (2,10-dimethyl-1,9-phenanthroline) hydrogen peroxide acts as a reductant of cu(ii). the reaction does not proceed in the absence of neocuproine and the addition of edta to the reaction mixture prior to addition of cu(ii) also inhibits the reduction. colour development can be arrested and stabilized by addition of edta. the reaction can be used to estimate hydrogen peroxide concentrations in the range 0.68-6.8 micrograms/ml and glucose conc ... | 1991 | 1770197 |
| biocytin: intracellular staining, dye-coupling and immunocytochemistry in carp retina. | correlation of electrophysiological and morphological, including ultrastructural, characteristics of neurones is important for understanding the functional organization of neuronal systems. further correlation with neurotransmitter content is essential for determining the neurochemical(s) used by a given neurone for propagating its signal. the two main neuronal markers presently available (lucifer yellow and horseradish peroxidase) are not satisfactory for correlating all three aspects. we have ... | 1991 | 1724386 |
| identification of single bacterial cells using digoxigenin-labelled, rrna-targeted oligonucleotides. | oligonucleotides were end-labelled with digoxigenin (dig), chemically at the 5'-end or enzymically at the 3'-end. following specific in situ hybridization of these probes to intracellular rrna molecules, the hybrids were detected with anti-dig fab fragments labelled with fluorescent dyes. the antibody fragments penetrated through the bacterial cell periphery and specifically bound to their antigens. probe-conferred and non-specific fluorescence per cell were quantified by flow cytometry and comp ... | 1991 | 1724265 |
| coupling of dihydroriboflavin oxidation to the formation of the higher valence states of hemeproteins. | the reactions between hydrogen peroxide and hemeproteins have been coupled to the oxidation of dihydroriboflavin so as to provide a simple method for measuring the rate constant of hemeprotein peroxidation. dihydroriboflavin rapidly reduces the higher oxidation states of iron and the hydroxy radicals which are the products of the hemeprotein/hydrogen peroxide reaction. the rapid reduction of these highly reactive compounds prevents the hemeproteins from undergoing irreversible chemical modificat ... | 1991 | 1659807 |
| chemical and transient state kinetic studies on the formation and decomposition of horseradish peroxidase compounds xi and xii. | previous studies on the chlorination reaction catalyzed by horseradish peroxidase using chlorite as the source of chlorine detected the formation of a chlorinating intermediate that was termed compound x (shahangian, s., and hager, l.p. (1982) j. biol. chem. 257, 11529-11533). these studies indicated that at ph 10.7, the optical absorption spectrum of compound x was similar to the spectrum of horseradish peroxidase compound ii. compound x was shown to be quite stable at alkaline ph values. this ... | 1991 | 1939231 |
| anatomical evidence for an intergeniculate leaflet in rana pipiens. | the projections of the nucleus of bellonci and the anterior thalamic nucleus in rana pipiens appear to be remarkably similar to those that have been described for the mammalian intergeniculate leaflet. the connections of these nuclei were examined using both the anterograde and retrograde transport of horseradish peroxidase. afferents to the neuropil of bellonci and its nucleus include bilateral projections from the retina, the contralateral nucleus of bellonci, and anterior thalamic nucleus as ... | 1991 | 1791987 |
| effects of cyanogen bromide modification of the distal histidine on the spectroscopic and ligand binding properties of myoglobin: magnetic circular dichroism spectroscopy as a probe of distal water ligation in ferric high-spin histidine-bound heme proteins. | magnetic circular dichroism (mcd) spectroscopy has been utilized to characterize the change in coordination structure in native ferric sperm whale myoglobin upon cyanogen bromide-modification. comparison of the mcd properties of the ferric high-spin state of cyanogen bromide-modified myoglobin (brcn-mb) with those of native ferric horseradish peroxidase and aplysia myoglobin suggests that ferric brcn-mb is a potential mcd model for the pentacoordinate state of ferric high-spin histidine-ligated ... | 1991 | 1954234 |
| a new population of neurons with crossed axons in the lamprey spinal cord. | neurons with contralateral, rostrally and caudally projecting axons were studied in whole mounts of lamprey spinal cord using retrograde labelling techniques with fluorescent dextran-amines, cobalt-lysine or horseradish peroxidase. a previously unknown large population (180-300 cells per hemisegment) of small (less than 25 microns) cells with contralateral projecting axons is described. their axons extend over less than 5 segments rostrally or caudally. the number of these cells per segment was ... | 1991 | 1723338 |
| purification and characterization of pea cytosolic ascorbate peroxidase. | the cytosolic isoform of ascorbate peroxidase was purified to homogeneity from 14-day-old pea (pisum sativum l.) shoots. the enzyme is a homodimer with molecular weight of 57,500, composed of two subunits with molecular weight of 29,500. spectral analysis and inhibitor studies were consistent with the presence of a heme moiety. when compared with ascorbate peroxidase activity derived from ruptured intact chloroplasts, the purified enzyme was found to have a higher stability, a broader ph optimum ... | 1991 | 16668537 |
| combination of horseradish peroxidase and lucifer yellow staining for selective labeling of neurons at the electron microscopic level. | we have developed a new double labeling method for electron microscopy to characterize selectively two physiologically identified neurons on the same preparation. the stomatogastric nervous system of crustaceans was used to test the distinguishing staining characteristics of the two labels. neurons were labeled on one side with horseradish peroxidase (hrp) and on the other side with lucifer yellow (ly). after blue light irradiation of the tissue in the presence of diaminobendizine, the two label ... | 1991 | 1918933 |
| tubular early endosomal networks in att20 and other cells. | using horseradish peroxidase (hrp) as a fluid-phase endocytic tracer, we observed through the electron microscope numerous tubular endosomes with a diameter of 30-50 nm and lengths of greater than 2 microns in thick sections (0.2-0.5 microns) of att20 cells. these tubular endosomes are multibranching and form local networks but not a single reticulum throughout the cytoplasm. they are sometimes in continuity with vesicular endosomal structures but have not been observed in continuity with att20 ... | 1991 | 1918157 |
| the effect of partial denervation of tibialis anterior (ta) muscle on the number and sizes of motorneurons in ta motornucleus of normal and dystrophic (c57bl dy2j/dy2j) mice. | the tibialis anterior (ta) muscle in one leg of normal (c57bl) and dystrophic (dy2j) mice was partially denervated by resection of a part of the lateral popliteal nerve. two months later the muscle was injected with horseradish peroxidase to permit visualization of the motorneurons that survived. partial denervation in both c57 and dy2j mice resulted in reduction of the number of motorneurons that supplied the muscle to approximately one-half the normal complement. the surviving motorneurons wer ... | 1991 | 1804521 |
| morphological correlates of response dynamics and efferent stimulation in horizontal semicircular canal afferents of the toadfish, opsanus tau. | 1. we used the intraaxonal labeling technique to study correlations between the terminal dendritic morphology of horizontal semicircular canal primary afferents and their response dynamics to sinusoidal head rotation and combined electrical stimulation of central efferent vestibular neurons. thirty-eight canal afferents were identified by their sensitivity and phase of response to rotation between 0.1 and 1.0 hz (+/- 10 degrees/s) and were subsequently labeled with horseradish peroxidase or bioc ... | 1991 | 1765791 |
| positional information determines the anatomy and synaptic specificity of cockroach filiform hair afferents using independent mechanisms. | mutant first instar cockroaches (periplaneta americana) with supernumerary filiform hair sensilla on their cerci were used to study the effects of cell body position on axonal morphology and synaptic connections. the wild-type cercus has two hairs, one lateral (l) and the other medial (m), each with an underlying sensory neuron. silver-intensified cobalt fills show that the supernumerary lateral neuron (sin) in the mutant has the same shape of arborization as l, and electrophysiological recordin ... | 1991 | 1724462 |
| immunocytochemical characterization of the suprachiasmatic nucleus and the intergeniculate leaflet in the diurnal ground squirrel, spermophilus lateralis. | the suprachiasmatic nucleus (scn) and the intergeniculate leaflet (igl) are retinorecipient structures that play important roles in the expression of circadian rhythmicity. we examined these two structures in a diurnal ground squirrel, spermophilus lateralis, using immunohistochemical techniques, and cholera toxin-bound horseradish peroxidase. a number of immunoreactive substances are distributed within the ground squirrel scn in a pattern similar to that reported in many other mammals. these in ... | 1991 | 1723927 |
| development and specificity of inhibitory terminal arborizations in the central nervous system. | this study examined the morphological development of single inhibitory arborizations in the gerbil central auditory brain stem. using a brain slice preparation, neurons of the medial nucleus of the trapezoid body (mntb) were filled with horseradish peroxidase (hrp), and their complete arborizations were analyzed along the tonotopic axis of the lateral superior olive (lso). the projections in neonatal animals displayed well-defined arbors that were ordered appropriately within the lso. it was evi ... | 1991 | 1663990 |
| sparing and recovery of function in spinal larval frogs (rana catesbeiana): effect of level of transection. | bullfrog tadpoles with cervical or midthoracic transection of the spinal cord were allowed to recover for 5 weeks, at which time axonal growth across the transection site was assessed by transport of horseradish peroxidase. weekly behavioral tests included those for posture, spontaneous locomotion, cutaneously elicited swimming, and intersegmental coordination. behavioral and electrophysiological assessments suggest that behavioral recovery depends, at least in part, on the growth of fibers acro ... | 1991 | 1662043 |
| internuclear neurons in the ocular motor system of frogs. | medial and lateral rectus motoneurons of frogs were localized after retrograde labeling with horseradish peroxidase (hrp) injected in the medial rectus muscle or applied on the cut end of the abducens nerve. coordinates of these cell columns were used as target areas for the injection of small amounts of hrp (20-60 nl) and [3h]leucine (25-40 nl) and as search areas for retrogradely and anterogradely labeled internuclear neurons (int) in in vivo and in vitro experiments. hrp injection in the medi ... | 1991 | 1761740 |
| olivary morphology and olivocerebellar topography in adult lurcher mutant mice. | in adult lurcher mice, in which virtually all cerebellar purkinje cells have degenerated as a direct consequence of mutant gene action, the inferior olivary complex suffers a severe retrograde transneuronal atrophy. our analysis indicates a 63% cell loss in the lurcher inferior olive, homogeneously distributed between the medial and dorsal accessory, and principal olivary subdivisions. olivary neurons are reduced in cross-sectional area by 30% in lurcher mice, compared to normal controls. all ol ... | 1991 | 1722225 |
| the dual oxygenase and peroxidase activities of porphobilinogen oxygenase and horseradish peroxidase: a study using the reaction with phenylhydrazine. | porphobilinogen oxygenase and horseradish peroxidase show dual oxygenase and peroxidase activities. by treating porphobilinogen oxygenase with phenylhydrazine in the presence of h2o2 both activities were inhibited. when horseradish peroxidase was treated in the same manner only the peroxidase activity was lost while its oxygenase activity toward porphobilinogen remained unchanged. the phenylhydrazine treatment alkylated the prosthetic heme group of porphobilinogen oxygenase and n-phenylheme as w ... | 1991 | 1656973 |
| the organization of projections from subdivisions of the auditory cortex and thalamus to the auditory sector of the thalamic reticular nucleus in galago. | anterograde and retrograde transport techniques were used to study the connexions between different subdivisions of the auditory cortex and thalamus with the thalamic reticular nucleus in the prosimian, galago. in particular, the goal was to determine whether the primary auditory nucleus, gmv, and its cortical target, area i of the auditory cortex (a i), project to a different region of the auditory sector of the reticular nucleus from the secondary auditory nuclei, gmmc and po and their cortica ... | 1991 | 12106239 |
| transport of 5-hydroxydopamine and horseradish peroxidase through the perilymph-endolymph barrier. | the distribution of 5-hydroxydopamine (5-ohda) and horseradish peroxidase (hrp) in the cochlea was examined by light and electron microscopy after perilymphatic perfusion. reaction product of 5-ohda was observed along the endolymphatic surface of the cochlear duct in both 10-minute and 30-minute perfusions, while that of hrp was observed only in the 30-minute perfusion. both tracers were found in pinocytotic vesicles of reissner's membrane, claudius' cells, and hensen's cells. no labeling was se ... | 1991 | 1952655 |
| spectroscopic and binding studies on the stereoselective interaction of tyrosine with horseradish peroxidase and lactoperoxidase. | the interaction of a series of derivatives of tyrosine with horseradish peroxidase (hrp) and lactoperoxidase (lpo) was studied by using optical difference spectroscopy, c.d. and proton n.m.r. spectroscopy in order to reveal differences in the mode of binding of l-tyrosine and d-tyrosine, which are substrates of but react at different rates with the two peroxidases, to hrp and lpo. all the donor molecules form 1:1 complexes with hrp and lpo, but they display a range of affinities for the enzymes. ... | 1991 | 1930142 |
| attenuation of 4-i-phenol-enhanced chemiluminescence by non-enhancer phenols. | the intensity of 4-i-phenol-enhanced chemiluminescence from the luminol-h2o2-horseradish peroxidase system is markedly attenuated in the presence of low concentrations of non-enhancer phenols. under the conditions studied, the effect is not associated with competition between 4-i-phenol and non-enhancer phenol for the enzyme intermediates, compounds i and ii, but involves a competition between non-enhancer phenol and luminol most probably for the 4-i-phenoxy radical. | 2013 | 1823551 |
| removal of hydroperoxides by immobilized borohydride: a good method for purification of biochemical materials. | borohydride was immobilized on a quaternary ammonium type anion exchange resin, amberlite ira-400, by an exchange reaction in n,n-dimethylformamide. the reducing ability of borohydride on the polymer beads was examined; 0.1 g resin was applied for about 30 min to 3 ml solutions of hydrogen peroxide, ethyl hydrogen peroxide, and peracetic acid, at a concentration of approximately 40 mm, m-chloroperbenzoic acid (3.13 mm), and 5-phenyl-4-pentenyl-1-hydroperoxide (1 mm), respectively. the solutions ... | 1991 | 1789421 |
| the synaptic organization of the prepacemaker nucleus in weakly electric knifefish, eigenmannia: a quantitative ultrastructural study. | weakly electric knifefish (eigenmannia sp.) produce continuous electric organ discharges at very constant frequencies. modulations of the discharges occur during social interactions and are under control of the diencephalic prepacemaker nucleus. abrupt frequency modulations, or 'chirps', which are observed predominantly during the breeding season, can be elicited by stimulation of neurons in a ventro-lateral portion of the prepacemaker nucleus, the so-called ppn-c. the ppn-c consists of approxim ... | 1991 | 1783940 |
| [a morphological classification of retinal ganglion cells in chinese hamsters]. | retinal ganglion cells in chinese hamsters were morphologically classified into alpha, beta and gamma cells by the horseradish peroxidase labeling method. the alpha cells had large somatic and dendritic fields. the beta cells were small to medium in somatic size and had small dendritic field size. the gamma cells had small to medium somatic and large dendritic fields. each cell type had either symmetrical or asymmetrical dendrites arising from the soma. the dendrites of alpha, beta and gamma cel ... | 1991 | 1746372 |
| chemiluminescent assay of enzymes using proenhancers and pro-anti-enhancers. | enhanced chemiluminescent assays for hydrolase enzymes have been developed using proenhancer and pro-anti-enhancer substrates. alkaline phosphatase is measured using disodium para-iodophenyl phosphate (proenhancer) which is converted to para-iodophenol and this in turn enhances the light emission from the horseradish peroxidase catalysed chemiluminescent oxidation of luminol by peroxide. an alternative strategy uses para-nitrophenyl phosphate which is converted by alkaline phosphatase to para-ni ... | 2006 | 1724339 |
| aluminum effect on the activity of superoxide dismutase and of other antioxygenic enzymes in vitro. | the effect of al on superoxide dismutase (sod) and on other antioxygenic enzymes: horseradish peroxidase, catalase, and glutathione peroxidase, has been investigated in vitro. in the case of sod, the effect of metal chelators (edta and deferoxamine) and a possible synergistic effect with iron salts have also been tested using the pyrogallol assay. there is no significant inhibitory effect of al on the activity of any of the above-mentioned enzymes. noticeable increases in sod activity were obser ... | 1991 | 1724179 |
| one-electron oxidation of trolox c and vitamin e by peroxidases. | direct reactions of peroxidases with trolox c (a vitamin e analogue) and vitamin e were observed in 50% (v/v) methanol. the kinetic results revealed that the reaction of horseradish peroxidase intermediate compound ii with trolox c and vitamin e was the rate-determining step, and the rate constants were estimated to be 1.7 x 10(3) and 5.1 x 10(2) m-1.s-1, respectively. peroxidases catalyzed the one-electron oxidation of trolox c and vitamin e, and the vitamin e phenoxyl radicals resulting from t ... | 1991 | 1663948 |
| high-valent intermediates in the reaction of n alpha-acetyl microperoxidase-8 with hydrogen peroxide: models for compounds 0, i and ii of horseradish peroxidase. | n-acetyl microperoxidase-8 (ac-mp-8) is a water soluble, ferric heme model for the peroxidases. the reaction of ac-mp-8 with h2o2 in 10 mm potassium phosphate over the ph range of 7-11 gives rise sequentially to relatively stable green and red species with properties that closely mimic those of hrp compounds i and ii, respectively. low-temperature stopped-flow studies of this reaction carried out in 50% v/v methanol/10 mm potassium phosphate, ph* 9.1 at -25.8 degrees c indicate that the pseudo-f ... | 1991 | 1656947 |
| motor protein independent binding of endocytic carrier vesicles to microtubules in vitro. | we have established an in vitro assay to characterize the binding of endocytic carrier vesicles to microtubules. magnetic beads coated with microtubules were used as an affinity matrix. a fraction from nocodazole-treated cells enriched in endocytic carrier vesicles, labeled with internalized horseradish peroxidase, was used in the binding experiments. binding of the endocytic carrier vesicles to microtubules in vitro was cytosol-dependent. this activity of cytosolic factors was saturable, heat-s ... | 1991 | 1917948 |
| afferent and efferent projections of the glossopharyngeal-vagal nerve in the hagfish. | anterograde and retrograde transport of horseradish peroxidase was used to examine the afferent and efferent projections of the glossopharyngeal-vagal nerve in the hagfish eptatretus burgeri. anterogradely labeled ganglion cells are scattered in the glossopharyngeal-vagal nerve trunk, in the saccular ganglion, and in the brainstem. afferent fibers of the glossopharyngeal-vagal nerve terminate in both the vagal lobe and the fasciculus communis. close observation showed no morphological differenti ... | 1991 | 1757601 |
| peroxidase-catalyzed s-oxygenation: mechanism of oxygen transfer for lactoperoxidase. | the mechanism of organosulfur oxygenation by peroxidases [lactoperoxidase (lpx), chloroperoxidase, thyroid peroxidase, and horseradish peroxidase] and hydrogen peroxide was investigated by use of para-substituted thiobenzamides and thioanisoles. the rate constants for thiobenzamide oxygenation by lpx/h2o2 were found to correlate with calculated vertical ionization potentials, suggesting rate-limiting single-electron transfer between lpx compound i and the organosulfur substrate. the incorporatio ... | 1991 | 1892813 |
| sensitive, colorimetric enzyme amplification cascade for determination of alkaline phosphatase and application of the method to an immunoassay of thyrotropin. | a highly sensitive flavin adenine dinucleotide-3'-phosphate (fadp)-based enzyme amplification cascade has been developed for determining alkaline phosphatase (alp; ec 3.1.3.1). the cascade detects alp via the dephosphorylation of the novel substrate fadp to produce the cofactor fad, which binds stoichiometrically to inactive apo d-amino acid oxidase (d-aao). the resulting active holo d-aao oxidizes d-proline to produce hydrogen peroxide, which is quantified by the horseradish peroxidase-mediated ... | 1991 | 1893577 |