bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemiluminescence properties of human, canine and rat polymorphonuclear cells
Authors: Lindena Joachim , Burkhardt Hannelore 
Published: May 2005

AbstractHuman as well as canine and rat polymorphonuclear cells (PMN) were separated from whole blood by centrifugation. Two‐step discontinuous Percoll gradients with distinct different densities were used. The chemiluminescence properties of the isolated PMN and of phagocytes in small quantities of whole blood were compared in luminol‐enhanced assays after stimulation with various agents: non‐opsonized zymosan (3.5 g/I), phorbol myristate acetate (PMA, 2.8 × 10−6 mol/I), calcium ionophore A 23187 (10−5 mol/l) and N‐formylmethionyl‐leucyl‐phenylalanine (FMLP, 3.5 × 10−6 mol/l). The isolated cells of the three species responded to all of the various stimuli. Species‐related sensitivity could be ordered: human > canine > rat. Response to the various agents in the human cells can be ranked: PMA ⩾ A 23187 > zymosan > FMLP; for the dog: A 23187 > PMA > zymosan > FMLP; and for the rat: zymosan ⩾ PMA > FMLP ⩾ A 23187. Time course and peak maximum response were different upon stimulation in the absence and presence of autologous plasma. Distinct soluble stimuli resulted in maximum responses below the baseline in the whole blood assays with canine (FMLP) and rat (FMLP, A 23187) phagocytes.
Different influences of cytochalasin B on the activation of human neurophils settled onto petri dishes displayed by simultaneously detected native and luminol‐dependent luminescence
Authors: Roschger Paul , Graninger Wolfgang , Klima Herbert 
Published: May 2005

AbstractCytochalasin B (CB) is known to interfere reversibly with the cytoplasmic contractile filamental network of mammalian cells. The role of the microfilament system in the mechanism of the reactive oxygen intermediates release of polymorphonuclear leukocytes (PMNL) was studied for different kinds of stimuli. PMNL from fresh human blood were treated with CB and stimulated by adherence on plastic surfaces, by opsonized zymosan, by phorbol myristate acetate and by N‐formylmethionyl‐phenylalaline. The production of reactive oxygen species were monitored by simultaneous detection of native, luminol‐independent, luminescence (NL) and luminol‐dependent luminescence (LDL) using a method of spectral discrimination. Different influences of CB on NL with respect to LDL as well stimuli‐dependent influences of CB on the luminescence response of PMNL were observed. Especially phagocytosis‐associated activation of PMNL was strongly inhibited by CB, whereas LDL was reduced to a much greater extent in comparison with NL. A firm involvement of the microfilament system is indicated, but it depends on the kind of stimulus engaged.
Chemiluminescence (CL) in blood samples reflects leukocyte activation (LA) during anaphylactoid reactions in dogs
Authors: Wilhelms O.‐H. , Lipponer L. , Seilnacht W. 
Published: May 2005

AbstractInflammation is accompanied by leukocyte activation (LA). We decribe a simple ex vivo technique for studying LA that might help to find new LA inhibitors for the treatment of pathologic events related to LA.Arterial and venous blood samples obtained from six permanently catheterized beagle dogs −60, 0, +15 min and +23 h after i.v. challenge with C 48/80, and also blood samples from six normal beagles, were minimally diluted 1:2.5 with buffer. Total leukocyte counts (LC), and luminol amplified CL, induced by opsonized zymosan (C3‐Z), were estimated. Blood samples from dogs elicited CL responses of almost 1/10 the magnitude of erythrocyte‐free human leukocytes, whereas blood samples from rats reacted three orders of magnitude less. Obviously quenching of CL by accompanying erythrocytes in blood samples from dogs is not important, for CL correlated almost linearly with the CL in differently diluted samples. In arterial, but not in venous samples from catheterized dogs, absolute CL and LC, both were significantly depressed (p < 0.05) 15 min after C 48/80 challenge. CL/106 leukocytes was augmented twofold. All leukocyte deviations returned to pre‐values 23 h post‐challenge.
A new fluorescence enhancement solution for Europium‐based time‐resolved fluoroimmunoassays
Authors: Degan Paolo , Abbondandolo Angelo , Montagnoli Giorgio 
Published: May 2005

AbstractA cationic detergent is proposed as suitable insulating agent for the preparation of a fluorescence enhancement solution useful for europium‐based time‐resolved fluoroimmunoassays. Luminescence from europium ions at concentration as low as 0.5 pmol/l can be detected in solution containing 1.6 mmol/l thenoyltrifluoroacetone, 110.5 μ mol/l Adogen 464 and 0.1% Tween 20, in the presence of 0.5 mol/l NaCl. A competitive TR‐FIA for rabbit lgG is described, showing that the new enhancement solution allows a sensitivity comparable to that of the high performance LKB Wallac DELFIA.
Bioluminescence decay kinetics in the reaction of bacterial luciferase with different aldehydes
Authors: Ismailov Anvar D. , Sobolev Alexander Yu. , Danilov Vadim S. 
Published: May 2005

AbstractAt 22°C the bioluminescence decay kinetics in the in vitro reaction catalysed by Vibrio harveyi luciferase in the presence of different aldehydes–‐nonanal, decanal, tridecanal and tetradecanal did not follow the simple exponential pattern and could be fitted to a two‐exponential process. One more principal distinction from the first‐order kinetics is the dependence of the parameters on aldehyde concentration. The complex bioluminescence decay kinetics are interpreted in terms of a scheme, where bacterial luciferase is able to perform multiple turnovers using different flavin species to produce light. The initial phase of the bioluminescent reaction appears to proceed mainly with fully reduced flavin as the substrate while the final one results from the involvement of flavin semiquinone in the catalytic cycle.
Effect of propagators and inhibitors on the ultraweak luminescence from maize roots
Authors: Radotić K. , Redenović Č. , Jeremić M. , Vučinić Ž. 
Published: May 2005

AbstractThis study has investigated the kinetics and mechanism of ultraweak luminescence in maize roots. Mannitol induced the second maximum and enhanced the main maximum of the relative intensity of luminescence from the roots. Hydroquinone and quinone enhanced the relative intensity of the luminescence. Catalase enhanced the maximum of the luminescence and changed the kinetics of the light emission. The effect of catalase on the kinetics was abolished by superoxide dismutase. Ascorbate in the presence of catalase reduced the luminescence maximum, but did not alter the kinetics. In the presence of catalase only, or in the combination with superoxide dismutase, or ascorbate, the luminescence intensity in the stationary phase was significantly lower compared to the control. The results support the participation of superoxide‐radical, singlet oxygen, electron transfer and the role of peroxidase in the reactions generating ultraweak luminescence in the roots. Ascorbate, catalase and superoxide dismutase have a protective role in the luminescent reactions.
A chemiluminescence assay for erythrophagocytosis
Authors: Downing I. , Templeton J. G. , Mitchell R. , Fraser R. H. 
Published: May 2005

AbstractA luminol‐dependent chemiluminescence assay for the assessment of the phagocytosis of erythrocytes sensitized with anti‐D IgG immunoglobulin by mononuclear leukocytes is described. The mononuclear leukocytes were obtained by apheresis enriched by centrifugation through a density gradient and stored in liquid nitrogen before use. The total reaction mixture, consisting of mononuclear leukocytes‐luminol‐erythrocytes (either anti‐D IgG sensitized or unsensitized controls) was 500 μl, light detection was by an LKB 1251 luminometer. Peak luminescence was seen between 35–45 minutes, the reaction being exhausted by 120 minutes. Determination of the reproducibility of the assay gave intra‐ and inter‐assay coefficients of variation of 5% and 13% respectively. We found the chemiluminescent response to be affected by the number of erythrocytes used in the assay and by the composition of the medium in which the cells were resuspended, particularly the pH at the initiation of the assay. We also compared the chemiluminescence assay to a microscopic phagocytic assay and found the results virtually identical. However, the former chemiluminescence assay was much easier to perform, marginally more sensitive, less laborious and eliminated any possibility of subjective error.
Activation of human monocytes by interleukin 2: Role of T lymphocytes
Authors: Ennen J. , Ernst M. , Flad H.‐D. 
Published: May 2005

AbstractThe effect of interleukin 2 (IL 2) on the capability of human monocytes to secrete reactive oxygen species triggered via Fc‐γ receptor (Fc‐γ R) function had been investigated by measurement of chemiluminescence (CL). IL 2 did not activate highly purified (hp) monocytes to respond to Fc‐γ R mediated phagocytic stimulation with an enhanced respiratory burst activity unless low numbers of T cells had been co‐cultured with hp monocytes. Supernatants from IL 2 treated PBMC contained interferon‐γ (IFN‐γ) and monocyte activating factor (MAF) activity. The secretion of both cytokine activities was strongly enhanced by cooperative function of monocytes. The correlation of IL 2 induced secretion of IFN‐γ and MAF activity was striking, however, monoclonal antibody (mAb) anti‐human IFN‐γ failed to abrogate IL 2 stimulated and lymphocyte dependent monocyte activation. Although IL 2 had no direct monocyte activating effect, pretreatment of hp monocytes with IL 2 led to monocyte priming: subsequent co‐culture with autologous control T cells enhanced the monocyte Fc‐γ R mediated CL response. The priming of monocytes by IL 2 was dependent on the interaction of IL 2 with the monocytic IL 2 receptor as shown by inhibition experiments with anti IL 2 R monoclonal antibody. Thus the IL 2 driven monocyte/T‐cell interaction leads to an increased Fc‐γ R mediated monocytic respiratory burst activity and to the secretion of a soluble MAF activity, but there were no detectable amounts of IFN‐γ.
Extra‐weak chemiluminescence of drugs XI. Quenching effects of purine and pyrimidine derivatives on the extra‐weak chemiluminescence derived from the maillard reaction
Authors: Kurosaki Yuichiro , Sato Hideaki , Mizugaki Michinao 
Published: May 2005

AbstractQuenching effects of purine and pyrimidine derivatives on the extra‐weak chemiluminescence (CL) derived from the Maillard reaction of L‐lysine with D‐arabinose were investigated The pyrimidine derivatives 2′‐deoxy cytidine, uridine, and uracil quenched the CL. Cytidine did not quench the CL. Purine derivatives, e.g. uric acid and 1‐methyl adenosine were particularly effective in quenching the CL. 5‐Methyl adenine and xanthine also quenched the CL, but adenosine had no effect. A comparison of the CL‐quenching abilities of compounds that have common basic structure was made; those with ribose at the 5‐position were the strongest quenchers. A linear relationship between CL‐quenching activity and the HOMO energy of the pi orbital for the various compounds was shown.
Nucleophilic addition to the 9 position of 9‐phenylcarboxylate‐10‐methylacridinium protects against hydrolysis of the ester
Authors: Hammond Philip W. , Wiese Wendy A. , Waldrop Alex A. , Nelson Norman C. , Arnold Lyle J. 
Published: May 2005

AbstractThe chemiluminescent reaction of an acridinium ester (AE) requires addition of peroxide to the 9 position of the acridinium ring. The addition of a hydroxide ion to the 9 position of an acridinium ester to form the carbinol adduct has also been well documented. We have observed a similar addition of other nucleophiles to the acridinium ring to form an acridan adduct. The adduct formed with bisulphite has been particularly well‐characterized for rate of formation, rate of reversion, and reaction equilibrium. The formation of an adduct (other than H2O2) has been demonstrated to decrease significantly the reactivity of the adjacent ester bond to alkaline hydrolysis. The resulting, more stable adduct is very useful when the acridinium ester is used as a label in DNA probe‐based assays. The adduct is highly resistant to hydrolysis under the conditions often desired for DNA probe‐based assays (high temperature, elevated pH, extended storage).
Measurement of rate constants for quenching singlet oxygen with a Cypridina luciferin analog (2‐methyl‐6‐[p‐methoxyphenyl]‐3,7‐dihydroimidazo[1,2‐a]pyrazin‐3‐one) and sodium azide
Authors: Mashiko Shinro , Suzuki Nobutaka , Koga Satoshi , Nakano Minoru , Goto Toshio , Ashino Toshihiko , Mizumoto Iwao , Inaba Humio 
Published: May 2005

AbstractThe rate constants for [1O2] [MCLA] and [1O2][NaN3] were measured by quenching the near‐infrared emission (1Δg→3∑g) in steady state with MCLA and NaN3, respectively. 1O2 was constantly generated by energy transfer to O2 from Ar laser‐excited Rose Bengal. The Stern—Volmer plots yielded the second‐order rate constants of 2.94 × 109 M−1 S−1 and 3.83 × 108 M−1 S−1 for quenching 1O2 with MCLA and NaN3 in water at pH 5.4, respectively. The 1O2 + MCLA reaction emitted light with maximum at 465 nm at pD 4.5 identical to the O2− + MCLA reaction.
Direct chemiluminescence immunoassay (CLIA) for muramyl tripeptide phosphatidyl‐ethanolamine in plasma
Authors: Gay B. , Towbin H. , Schnell C. , Einsle K. , Graf P. , Gygax D. 
Published: May 2005

AbstractA competitive chemiluminescent immunoassay for quantitation of muramyl tripeptide phosphatidyl‐ethanolamine (MTP‐PE) in plasma has been developed. The assay is based on the use of an acridinium ester‐labelled analogue of muramyl tripeptide and a rabbit antiserum. It includes an overnight incubation and a separation with a second antibody covalently coupled to paramagnetic particles. The sensitivity of detection is 0.012 nmol/l, the assay working range is 0.1‐5 nmol/l, and the inter‐assay CVs are ⩽ 10%. Using up to 6000‐fold sample dilutions, a wide working range (0.1‐30 000 nmol/l) is obtained. Rat plasma samples were collected during and one day after intravenous infusion of MTP‐PE. Following infusion, the concentrations in plasma declined multiphasically. Half‐life time was 0.37 h ± 0.03 (mean ± SD, alpha phase) and 1.76 h ± 0.08 (mean ± SD, beta phase), clearance and volume of distribution were 0.09 ± 0.02 l/h × kg (mean ± SD) and 0.06 ± 0.01 l/kg (mean ± SD) respectively. The use of an acridinium ester as a chemiluminescent (CL) label overcomes the problems associated with reagents of limited shelf‐life.
The effects of N‐ethylmaleimide on extracellularly and intracellularly generated chemiluminescence in neutrophils indicate that the rate of deactivation of NADPH‐oxidase is higher when the oxidase system is localized on the plasma membrane than when it is localized on the phagosomal membrane
Authors: Dahlgren Claes , Sundqvist Tommy 
Published: May 2005

AbstractSustained generation of reactive oxygen metabolites following respiratory burst activation in neutrophils is a result of continued replenishment of a pool of active NADPH‐oxidase. The sulphydryl‐modifying reagent N‐ethylmaleimide (NEM) has been shown to be without effect on the turnover of activated NADPH‐oxidase but to inhibit the replenishment of active oxidase molecules (Akard et al., 1988). NEM was thus used to determine the rate of deactivation of extracellularly and intracellularly generated chemiluminescence in human neutrophils. We have shown that deactivation is more rapid when activation leads to a release of oxygen metabolites (extracellular chemiluminescence) than when the metabolites are generated intracellularly. The results indicate that the rate of deactivation of NADPH‐oxidase is higher when the oxidase system is localized on the plasma membrane than when it is localized on the phagosomal membrane.
Extraction and analysis of superoxide free radicals (·O−2) from whole mammalian liver
Authors: Shoaf Antony R. , Shaikh Ali U. , Harbison Raymond D. , Hinojosa Oscar 
Published: May 2005

AbstractExtraction of whole lobes of normal rat liver with dimethyl sulphoxide (DMSO) under N2 gives extracts which contain 5—10 μmol/l·O−2 (50‐100 nmol·O−2 per 10 ml extract per 4 g liver; 1.25‐2.50 nmol·O−2 per millilitre per gram liver). Evidence for ·O−2 in the extracts is given by: (1) electron spin resonance signals (ESR), (2) differential pulse polarography (DPP), (3) chemiluminescence (CL), and (4) nitroblue tetrazolium reduction (NBT). All tests yield results identical with those obtained with authentic ·O−2. Extraction of ·O−2 is enhanced by tetrabutyl ammonium ion, and is maximal at 1‐3 min. These results raise the possibility that substantial amounts of ·O−2 are normally sequestered in protective membranous sites in vivo.
Weak chemiluminescence of bilirubin and its stimulation by aldehydes
Authors: Watanabe Haruo , Usa Masashi , Kobayashi Masaki , Agatsuma Shin‐Ichi , Inaba Humio 
Published: May 2005

AbstractBilirubin in an alkaline solution exhibits a weak chemiluminescence (CL) under aerobic conditions. This spontaneous CL was markedly enhanced by the addition of various aldehydes. The fluorescent emission spectrum of bilirubin, excited by weak intensity light at 350 nm, coincided with its CL emission spectrum (peak at 670 nm). CL emission from bilirubin was not quenched by active oxygen scavengers. This suggests that triplet oxygen reacts with bilirubin, and forms an oxygenated intermediate (hydroperoxide) as a primary emitter (oxidative scission of tetrapyrrole bonds in bilirubin is not involved in this CL). The Ehrlich reaction (test for monopyrroles) and hydrolsulphite reaction (test for dipyroles) on the CL reaction mixture and unreacted bilirubin showed no differences. When the CL was initiated by singlet oxygen, rather than superoxide anion, monopyrrole, was detected in the reaction products by gel chromatography. The inhibitory effect of a scavenger of singlet oxygen on CL was eliminated in the presence of formaldehyde. Therefore, triplet carbonyl, formed by singlet oxygen through the dioxetane structure in bilirubin, is not an emitter. The reaction mechanism of bilirubin CL and the formation of a hydroperoxide intermediate is discussed in relation to the chemical structure of luciferin molecules from bioluminescent organisms.
Enhanced chemiluminescence in the oxidation of luminol and an isoluminol cortisol conjugate by hydrogen peroxide in reversed micelles
Authors: Metelitza D. I. , Eryomin A. N. , Shibaev V. A. 
Published: May 2005

AbstractThe chemiluminescent oxidation of luminol and an isoluminol cortisol conjugate (ABICOR) by hydrogen peroxide has been studied in cetyltrimethylammonium bromide (CTAB) reversed micelles in octane‐chloroform (1 : 1). The maximum chemiluminescence intensity of both compounds is dependent on the initial concentrations of the H2O2 and substrates, the pH value of the micelle polar phase and the H2O/CTAB ratio. The optimum pH ranged from 8.5 to 9.5. Under comparable conditions, the chemiluminescence intensity for luminol was 15‐fold higher than for the ABI‐COR conjugate. A mechanism of oxidation of the substrates in reversed micelles is proposed and the possible mechanisms of inhibition by the substrate and oxidant is discussed.
A survey of more than 90 commercially available luminometers and imaging devices for low‐light measurements of chemiluminescence and bioluminescence, including instruments for manual, automatic and specialized operation, for HPLC, LC, GLC and microtitre plates. Part 2: Photographs
Authors: Stanley Philip E. 
Published: May 2005

AbstractPart 1 of this survey comprised a description of the luminometers (J. Biolumin. Chemilumin. 7, 77‐108 (1992)) and was compiled in January and February 1992 from information available in public domain literature requested by and supplied to the author by numerous companies in the previous two months. This part includes photographs of around 40 of these instruments. It is intended that updates to this review will be published at least annually in this journal and suppliers are invited to provide full technical details of new luminometric equipment to the author.
In vitro effect of ascorbic acid on neutrophil–endothelial cell interaction
Authors: Jonas Eleonore , Dwenger Alexander , Hager Anke 
Published: May 2005

AbstractThe effect of different concentrations (0.06, 0.6 and 6.0 mmol/L) of ascorbic acid on neutrophil–endothelial interaction was studied using an in vitro model of human umbilical cord vein endothelial cells and human neutrophils. The aim of the study was to determine changes in chemiluminescence response of neutrophils during adherence to endothelial cells. Because adherence of neutrophils to endothelial cells is an essential component in inflammatory processes leading to endothelial cell injury, the influence of ascorbic acid on adherence and endothelial cell injury have been investigated. Production of oxygen‐derived metabolites, measured by chemiluminescence response of neutrophils, decreased significantly in the presence of 6 mmol/L ascorbic acid during coincubation of neutrophils and endothelial cells (p < 0.025). The adherence of neutrophils to endothelial cells was significantly decreased at a concentration of 6 mmol/L (p < 0.0005). The inhibition of neutrophil adherence to endothelial cells was correlated with a diminished neutrophil‐mediated endothelial cell injury during incubation with 6 mmol/L ascorbic acid (p < 0.0005). The present results indicate that ascorbic acid might exert a protective effect on neutrophil‐mediated endothelial cell injury by decreasing adherence of neutrophils to endothelial cells and by scavenging reactive oxygen metabolites. Moreover, the current investigation points to probable protective effect of ascorbic acid on oxidant‐mediated cell damage in diseases (e.g., Adult Respiratory Distress Syndrome).
Interaction between myeloperoxidase and antibodies against myeloperoxidase measured by chemiluminescence
Authors: Nässberger Lennart 
Published: May 2005

AbstractWe investigated interaction between antibodies directed against myeloperoxidase (anti‐MPO) and myeloperoxidase (MPO) with chemiluminescence. Whole serum diluted 1/10 containing circulating anti‐MPO antibodies as well as serum from normal blood donors inhibited myeloperoxidase (MPO) enzyme activity when incubated with 1.42 m̈g MPO. When further diluted the inhibitory effect was abolished. Incubation with purified human lgG fraction of anti‐MPO, did not cause any inhibition when diluted 1/10 and incubated with 1.42 m̈g MPO. When adding MPO to normal sera a rapid increase of the enzyme activity was seen above 5 m̈g, and the inhibitory effect was completely abolished when 10 m̈g was added. Both sera from healthy individuals, as well as sera from patients with circulating anti‐MPO inhibited MPO activity. The inability of pure lgG fractions from anti‐MPO sera to inhibit MPO enzyme activity, clearly indicates the presence of an inhibitory factor, unspecific or specific, in serum.
Application of in vivo bioluminescence to the study of lonophoretic action
Authors: Simpson W. J. 
Published: May 2005

AbstractIonophores (carbonyl cyanide m‐chlorophenylhydrazone; valinomycin; and the hopderived compounds colupulone, trans‐isohumulone and trans‐humulinic acid) reduced the rate of dodecanal‐dependent light emission from luxA/B‐transformed cells of Lactococcus lactis subsp. diacetylactis F712 when the cells were suspended in a buffered medium (pH 6.4) containing glucose. This allowed an assay for ionophores to be devised and permitted measurement of the effects of such compounds on the test organism by the use of a non‐destructive technique in real time.