bluuebunny/crossref_metadata_2025_split huggingface dataset:
Affinity purification of bacterial luciferase and NAD(P)H:FMN oxidoreductases by FMN‐sepharose for analytical applications
Authors: Lavi Jukka T. , Raunio Raimo P. , Stahlberg Tom H. 
Published: May 2005

AbstractA modified purification method for bacterial luciferases and NAD(P)H:FMN oxidoreductases is described which uses FMN‐Sepharose alone or coupled to DEAE ion exchange chromatography for the simultaneous purification of luciferase and the various oxidoreductases from Vibrio harveyi, a bright mutant of Vibrio harveyi, Vibrio fischeri, and Photobacterium phosphoreum. This purification method is compared with DEAE‐Sepharose CI 6B fractionations from these organisms. Both methods allow the separation of oxidoreductases specific for either NADH or NADPH. The use of FMN‐Sepharose coupled to DEAE‐Sepharose fractionation allows the isolation of highly purified enzymes. Lacking interfering factors, these are very suitable for various analytical applications based on bacterial bioluminescence enzymes. The partially purified enzymes from the affinity column have higher specific activities than those obtained using DEAE‐Sepharose.
Chemiluminescence of irradiated animal blood plasma
Authors: Kavetsky R. E. , Serkyz Ya. I. , Druzhina N. A. , Pinchouk V. G. 
Published: May 2005

AbstractSpontaneous and induced chemiluminescence of rat blood plasma following irradiation of the animals with fast neurons was studied. Dynamics of the luminescence reflected the degree of radiation injury and an oscillatory response of blood chemiluminescent effect was observed.
Chemiluminescent reactions in the Belousov‐Zhabotinskii oscillating system
Authors: Zhuravlev A. I. , Trainin V. M. 
Published: May 2005

AbstractChemiluminescence (CL) occurs during reactions of several of the components of the CH2 (COOH)2KBrO3MnSO4H2SO4 self‐sustained system. In contrast to the kinetics determined using potentiometry and spectrophotometry, the CL intensity kinetic curve during the oxidation of manganese (II) ions by acidic bromate has an extremum. Experimental dependences of the maximum CL intensity value on the initial reagent concentrations have been determined and compared with the results of the numerical simulation based on the commonly accepted Noyes‐Field‐Thompson mechanism.
Three‐peaked chemilluminescent response of human peripheral blood leukocytes following stimulation with phytohaemagglutinin (PHA)
Authors: Warren N. , Jones A. E. , Bater A. J. 
Published: May 2005

AbstractLuminol‐enhanced chemiluminescence (CL) was used to examine the response of various leukocyte populations following stimulation with a crude extract of Phaseolus vulgaris, namely phytohaemagglutinin (PHA‐C). Populations stimulated included a human peripheral mixed leukocyte preparation (MLP), and purified preparations of lymphocytes, monocytes and polymorphonuclear leukocytes (PMNL). Mouse peritoneal exudate cells and the lymphocytic cells lines Molt #4 and Daudi were also stimulated. Following stimulation, a characteristic three‐peaked chemiluminescent response was obtained from the MLP population. Little or no response was obtained from the purified lymphocytes. Monocytes produced a sharp peak corresponding to the second peak of the MLP response and PMNL produced a broad peak corresponding to the third peak of the MLP response. Mouse peritoneal exudate cells containing lymphocytes and monocytes/macrophages showed a two‐peaked stimulation which corresponded to the first two peaks of the MLP response. Molt #4 and Daudi showed no chemiluminescence if stimulated individually, but if added to a MLP substantial enhancement of the first and second peaks was observed. These results indicate some form of lymphocyte/monocyte interaction leading to enhanced CL following PHA‐C stimulation.
A luminometric method for the determination of ATP and phosphocreatine in single human skeletal muscle fibres
Authors: Wibom R. , Söderlund K. , Lundin A. , Hultman E. 
Published: May 2005

AbstractA sensitive method for the analysis of ATP and phosphocreatine (PCr) in single human skeletal muscle fibres is described. Muscle tissue was freeze‐dried and single fibres were dissected free with the aid of low‐power microscopy. The fibres were then extracted in trichloroacetic acid and neutralized with KHCO3. The assay is based on the continuous monitoring of light produced as a result of ATP degradation in the firefly luciferase reaction. PCr is measured as the amount of ATP formed in the creatine kinase reaction. The coefficient of variation was less than 4% for both ATP and PCr determination. The amount of tissue required for the assay is approximately 0.5 μg (dry weight). The assay showed good agreement with spectrophotometric and high‐performance liquid chromatographic (HPLC) measurements made upon extracts of whole muscle tissue.
Bovine serum albumin interacts with bacterial luciferase
Authors: Makemson John C. , Hastings J. Woodland 
Published: May 2005

AbstractBovine serum albumin (BSA) affects the amount of light obtained from bacterial luciferase by competing with luciferase for one of the luciferase substrates, the aldehyde. At low aldehyde concentrations BSA behaves as an inhibitor, but at high aldehyde concentrations BSA relieves substrate inhibition. BSA reversibly binds decanal with a Ksi = 3.36 μmol/l, approximately half the affinity of luciferase for decanal (KM = 1.5 μmol/l). BSA also increased the rate of intermediate II dark decay. The data suggest that this involves a direct protein‐protein (BSA‐luciferase) interaction.
Differences in the respiratory burst of human polymorphonuclear leukocytes induced by virulent and avirulent Legionella pneumophila Serogroup 1
Authors: Rajagopalan‐Levasseur Premavathy , Dournon Eric , Vilde Jean‐Louis , Pocidalo Jean‐Jacques 
Published: May 2005

AbstractTwo strains of Legionella pneumophila of different virulence were examined for their influence on the metabolic oxidative activity of human polymorphonuclear leukocytes. The leukocytes exhibited decreased rates of oxygen consumption and diminished chemiluminescence activity following phagocytosis of a virulent strain of L. pneumophila serogroup 1. In contrast, phagocytosis of its multipassaged derivative rendered avirulent, was accompanied by increased rates of both oxygen consumption and chemiluminescence activity. Although no differences were observed in oxygen uptake induced by the virulent legionellae compared to leukocytes at rest, statistically significant differences were observed in the chemiluminescence responses. These observations were not unexpected, since the luminol‐enhanced chemiluminescence assay, is more sensitive than the oxygen uptake assay. In spite of decreased metabolic activity of PMN in the presence of virulent legionellae, electron microscope studies showed higher numbers of intracellular L. pneumophila than the avirulent subtype. Thus, virulent and avirulent L. pneumophila can be differentiated on the basis of oxygen consumption and chemiluminescence assays.
Leukocytes as immunosensors: An immunoassay without labelled reagents
Authors: Lilius Esa‐Matti , Kankaanpää Anne , Lahti Reijo 
Published: May 2005

AbstractA novel quantitative nonlabel immunoassay is described. It is based on the recognition of antigen‐antibody complexes by the Fc‐receptors of phagocytic leukocytes and the subsequent activation of these cells. Activation which is proportional to the amount of immune complexes present can be detected by measuring the intensity of chemiluminescence emitted by the activated cells. In addition to determinations of an antigen and an antibody, the binding capacity of complement to antigen‐antibody complexes can be estimated.
Reactions of copper complexes with oxygen radicals generated by human neutrophils
Authors: Haseloff Reiner F. , Gruner Stefan , Wischnewsky Gerd G. 
Published: May 2005

AbstractThe intensity of the chemiluminescence of unstimulated human neutrophils in the presence of luminol was used to investigate the effects of low‐molecular‐weight copper complexes at the cellular level. In different models (superoxide dismutase mimetic activity, inhibition of haematoporphyrin derivative/light‐induced lysis of cells), the biological activity of the complexes exceeded the activity of the ligands alone.
Light‐induced biophotonic emission from plant tissues
Authors: Bajpai R. P. , Bajpai P. K. 
Published: May 2005

AbstractThe emission of biophotons in the visible range, following a delay time of 2‐200 seconds after exposure to light, has been measured in germinating seeds, roots, flowers, leaves, and cells. It was found that the biophotonic signals are reproducible and light‐induced. The observed signals from germinating seeds of Phaseolus aures and decaying leaves of Eucalyptus are presented to show that the signals have characteristic kinetics and intensity. The kinetics of the signal was found to be independent of the stage of growth or decay, though its intensity varied with biological factors. The kinetics in the first minute is characterized by a single exponential decay term while that in the region t ≤ 200 s is characterized by two exponentials. The variation in the intensity of the signal with mass, state of hydration, and growth, and the effect of inhibitors in various systems (e.g. leaves, lichen, Chlorella) are reported.
Cross‐reactivity of a commercial chemiluminescence immunoassay for human chorionic gonadotropin with the free β‐subunit
Authors: Luppa P. , Spöttl G. , Saller B. , Neumeier D. , Mann K. 
Published: May 2005

AbstractAn enhanced chemiluminescence immunoassay for the determination of serum human chorionic gonadotropin (HCG) in specimens from oncology patients has been assessed with respect to its cross‐reactivity with the free HCG ββ‐subunit (HCG‐β). The assay, standardized against the First International Reference Preparation 75/537, had a crossreactivity with the free β‐subunit of 625% (molar basis). Therefore this assay achieves high sensitivity for the detection of either intact HCG or free HCG‐β in serum of patients with seminomatous or nonseminomatous testicular cancers. Results of both assays, the in‐house immunoradiometric assay (+ HCG‐β) and the Amerlite HCG‐60 assay, showed a close correlation (R =0.854−0.960) when serum samples from tumour patients were analyzed. Moreover, the content of free β‐subunit determined in a specific HCG‐β assay, could be quantitatively measured in the enhanced chemiluminescence immunoassay. Thus, this assay is suitable for oncology use, but also highlights the limitations of measuring HCG in serum samples.
Determination of serum oxalate using peroxyoxalate chemiluminescence of free oxalic acid
Authors: Albrecht S. , Hornak H. , Freidt T. , Böhm W. D. , Weis K. , Reinschke A. 
Published: May 2005

AbstractWe describe a new sensitive and specific method for determination of oxalate in human serum. By using the chemiluminescence decay of monoperoxyoxalic acid very low concentrations of oxalate (200 nmol/L) can be determined. The mean serum oxalate level in apparently healthy controls was 14.5 ± 8.5 m̈mol/L. Supplementation of ascorbic acid leads to an increase in serum oxalate level. While serum oxalate concentrations of calcium oxalate stone formers (x = 16.4 ± 9.8 m̈mol/L) are not significantly different from the control group, an extreme increase of serum oxalate is evident in haemodialysis patients. The serum oxalate concentration decreased during dialysis treatment from 141.4 ± 32.1 m̈mol/L to 36.4 ± 12.7 m̈mol/L.
Flow injection chemiluminescence study of acridinium ester stability and kinetics of decomposition
Authors: Littig Janet S. , Nieman Timothy A. 
Published: May 2005

AbstractDecomposition of phenyl acridinium‐9‐carboxylate is monitored using electrogenerated chemiluminescence in a flow system. The formation of the pseudobase from the acridinium ester [AE] is described by rate = k′1[AE] + k″1[AE][OH−]0.5, where k′1 = 0.020 ± 0.006 s−1 and k″1 = 2.1 ± 0.8 (L/mol)−0.5 s−1. Irreversible decomposition of the pseudobase is described by rate = k′2[AE][OH−], where k′2 = 20.1 ± 3.8 (L/mol s). These kinetic equations, plus measurement of variation in emission intensity for constant acridinium ester concentration, are used to predict the resulting emission intensity v. pH behaviour given various contact times (in the 0.25 to 25 s range) for the acridinium ester to be in an alkaline solution prior to initiation of the chemiluminescence reaction.
Improved preparation of leukocytes for chemiluminescent study of human phagocytic leukocyte‐generated reactive oxygen species
Authors: Saniabadi Abby R. , Nakano Minoru 
Published: May 2005

AbstractLeukocyte oxidative function was investigated in a more physiological milieu than currently used in the chemiluminescence (CL) technique. Heparinized blood was mixed with 6% dextran‐T70 (9:1) and the leukocyte‐rich plasma obtained without centrifugation was used for the CL experiments (phagocyte count was adjusted to 0.7 × 106/mL with Hanks' buffer) (method A). In this medium, phagocytes responded to stimulation by opsonized zymosan, producing strong luminescence in the presence of 0.5 m̈ mol/L MCLA. CL was inhibited by superoxide dismutase, suggesting that the luminescence reaction was attributable to O. Granulocytes were also prepared by the usual method involving centrifugation and were then suspended in plasma (method B). Oxidative function of phagocytes prepared by the two methods was studied together with whole blood as aliquots diluted with Hanks' buffer up to a factor of 1000. Luminescence reached a peak value at a dilution factor of 16, but at very high dilutions luminescence decreased sharply. Significantly higher luminescence values were obtained with samples from method A. Luminescence of whole blood peaked at a dilution factor of 248 but it was less than the value obtained using samples prepared by method A or B. As samples prepared by method A contain all the leukocyte populations, platelets, residual red cells and plasma proteins, the assay of leukocyte‐generated reactive oxygens using CL is attained in more physiological conditions than method B in which leukocytes may be damaged owing to repeated centrifugation and hypotonic shock.
Processing biological images from very low light emissions
Authors: Bernroider Gustav 
Published: May 2005

AbstractAs opposed to strong light signals (>108 photons mm−2 s−1), the construction of images from object sources with low level signals (<102 photons mm−2 s−1) involves a probabilistic transfer‐ or point‐spread function. The resulting images carry considerable uncertainty or spread, restricting resolution and quantification. In this paper we propose various strategies how to recontruct object characteristics from very low light emissions by unfolding the imaging equation. Further, calibration techniques which help to associate light emissions with the decomposition of luminogenic substrates in a spatially selective way will be discussed.
CCD camera imaging for the chemiluminescent detection of enzymes using new ultrasensitive reagents
Authors: Akhavan‐Tafti Hashem , Schaap A. Paul , Arghavani Zahara , Desilva Renuka , Eickholt Robert A. , Handley Richard S. , Schoenfelner Barry A. , Sugioka Katsuaki , Sugioka Yumiko 
Published: May 2005

AbstractWe have designed and constructed an inexpensive imaging system based on charge coupled device (CCD) technology and utilized it to demonstrate the sensitivity and rapid detection possible with Lumigen® chemiluminescent reagents. We also report the development of two new chemiluminescent reagents, Lumi‐Phos® Plus and Lumigen PS. Lumi‐Phos Plus is an ehanced formulation for the rapid detection of alkaline phosphatase on membranes and in solution. It provides excellent images in blotting applications with exposures of under a minute. Lumigen PS represents a new generation of peroxidase detection reagents. The wide dynamic range with excellent linearity, higher signal and lower background than other chemiluminescent reagents make Lumigen PS of unsurpassed value in enzyme‐linked immunoassays and nuclic acid probe assays using HRP conjugates.
Low‐light image analysis of transgenic organisms using bacterial luciferase as a marker
Authors: Langridge W. , Escher A. , Wang G. , Ayre B. , Fodor I. , Szalay A. 
Published: May 2005

AbstractMethods for measurement of a novel light‐emitting reporter gene system in bacteria, yeast, plant cells, plant tissues and intact plant organs are described. The principle underlying the assay procedures is the bacterial luciferase catalysed oxidation of reduced flavin mononucleotide (FMNH2) in the presence of the ten carbon aldehyde decanal, to yield FMN, decanoic acid, water and a photon of light at 490 nm which can be captured by X‐ray film, a photomultiplier tube or, for in vivo measurements, an image‐intensifier coupled to a video camera. This light measuring assay system is sensitive, easy to use, inexpensive, does not require radioactivity, and has been used successfully for rapid detection of bacterial transformants, the quantitative measurement of transient and stable gene expression in bacteria and yeast, and in vivo measurement of temporal and spatial gene expression throughout plant and animal development.
Use of lux genes in applied biochemistry
Authors: Hill Philip J. , Stewart Gordon S. A. B. 
Published: May 2005

AbstractBioluminescence has emerged in the last decade as a major tool for the study of bacterial adaptation and survival. In addition to the advantages of sensitivity and the real‐time, non‐invasive nature of this reporter, the imaging potntial of using low‐light and photon‐counting video cameras has been particularly influential in establishing its ascendancy over more traditional reporter systems. This review provides a reflection of personal activity in this field through applications in Food Microbiology and collaboration with colleagues both in the UK and beyond.
A method for measuring microquantities of DNA
Authors: Giachè Valentino , Pirami Laura , Becciolini Aido 
Published: May 2005

AbstractQuantitative analysis of DNA content represents a critical step when only very small amounts of nucleic acids are available. The DNA content of a small RNA‐free sample can be measured in a simple and precise way using a two‐dimensional approach. DNA samples are spotted on the surface of an agarose gel containing ethidium bromide (EtBr) and the ultraviolet‐induced low‐light fluorescence emitted by EtBr molecules intercalated into the DNA is evaluated. The high sensitivity and reproducibility of this quantitative method has been obtained using an advanced analysis system capable of distinguishing low‐light fluorescent patterns, as in the case of DNA stained with EtBr, from the background. Use of an internal standard is necessary because the intensity of the signal is due to the aperture of camera diaphragm and to gel conditions. Using this two‐dimensional analysis system it is possible to obtain rapid and precise quantitation of as little as 2ng of DNA.
The enhancement of iron‐dependent luminol peroxidation by 2,2′‐Dipyridyl and nitrilotriacetate
Authors: Henley R. , Worwood M. 
Published: May 2005

AbstractThe generation of radicals from luminol and H2O2, in the presence of iron and iron chelates was monitored by measuring the chemiluminescence produced by further oxidation of these radicals. 2,2′‐Dipyridyl enhanced the production of chemiluminescence in the presence of FeSO4, farritin and haemosiderin but not FeCI3 or horseance of both FeSO4 and FeCI3 but not ferritin or haemosiderin. The enhancement of chemiluminescence by iron chelation may have analytical applications and the process by which these iron chelates are able to generate radicals from the nitrogenous base luminol may be similar to that responsible for their toxic effects on DNA.
The influence of age and sex on phagocyte chemiluminescence
Authors: McCafferty Ann C. , Cree Ian A. , McMurdo Marion E. T. 
Published: May 2005

AbstractThe process of ageing is associated with increased susceptibility to infection. Phagocytes form the primary defence mechanism against infecting microorganisms, but the influence of ageing on phagocyte function remains controversial. In this study we have applied a microtitre plate phagocyte chemiluminescence (CL) assay suitable for clinical use to compare phagocyte oxidative metabolism in younger healthy subjects (age 20–60 years) and healthy older (60–70 years) subjects. Polymorphonuclear leukocytes (PMNL) and monocytes were stimulated using phorbol myristate acetate (PMA), serum opsonized zymosan (SOZ), and non‐opsonized zymosan (ZYM) in the presence of both lucigenin and luminol. Monocytes showed a higher luminolenhanced CL response to PMA in males compared with females in the younger age group. No PMNL differences were observed between the sexes. Although no difference were found in relation to age when cells were stimulated with PMA and SOZ, significantly lower background (unstimulated) CL was obtained from PMNL with luminol. PMNL luminol‐enhanced CL responses were also lower in response to ZYM. The findings suggest a reduced response of PMNL from older subjects to minimal stimulation. This could be related to abnormalities in the triggering of the respiratory burst or myeloperoxidase release due to ageing. The influence of age and sex should be taken into account in clinical studies of phagocyte CL.
Enhanced chemiluminescence of lucigenin with epinephrine in cationic surfactant micelles containing periodate
Authors: Kamidate Tamio , Ichihashi Hiroyuki , Segawa Tadashi , Watanabe Hiroto 
Published: May 2005

AbstractEpinephrine (EP) species involved in the lucigenin chemiluminescence (CL) were identified in alkaline solution by comparing the time course of the CL response and the formation of EP oxidation products. EP quinone and adrenolutine (AL) were found to be responsible for the lucigenin‐CL reaction. The mechanism of the lucigenin‐CL enhancement was investigated using cationic micellar hexadecyltrimethylammonium hydroxide (CTAOH), periodate, and a mixture of micellar CTAOH and periodate. The CL enhancement in the presence of micellar CTAOH and periodate could be explained in terms of increases in the oxidation rate of EP to EP quinone and the intramolecular oxidation rate of adrenochrome to AL.
Comparison of the performance of the borax buffer‐based HRP‐enhanced reagent and the ‘Lumi‐Phos 530’ chemiluminescence systems in the detection of biotinylated DNA
Authors: Cercek Bibijana , Roby Keith , Siaw Martin 
Published: May 2005

AbstractA comparison of two chemiluminescence methods, the borax buffer‐based HRP‐enhanced reagent and Lumi‐Phos 530, applied to the detection of a biotinylated 30‐mer DNA slot blotted onto a nylon membrane, is presented. A streptavidin–HRP and streptavidin–ALP mediated detection system was used. The HRP‐enhanced system is up to 15‐fold greater with respect to the signal/background ratios than the Lumi‐Phos 530 system at 0.5 μg biotinylated DNA with at least a two‐fold improvement in detection sensitivity for 0.5 ng biotinylated DNA.