bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automation and computerization of chemiluminescence: A new methodological approach in the study of human phagocytes
Authors: Parente R. , Melotti C. 
Published: May 2005

AbstractPeripheral blood phagocytic cells (PMNLs) are activated by contact with opsonized particles. Metabolic activation of PMNLs is associated with a remarkable increase in the respiratory burst and generates high energy oxygen compounds which are responsible for the bactericidal activity of PMNLs and for their ability to produce luminol‐dependent chemiluminescence (CL). The CL phenomenon is measured by an automated and computerized photoluminometer (Berthold LB950) in whole blood stimulated with opsonized zymosan.This whole blood method of CL measurement has been applied to the study of the phagocytic process and to the investigation of cellular and humoral abnormalities in several pathologies, indicating this assay as a simple, rapid and reliable test.
Comparison of serum free thyroxine measurements by chemiluminescence and equilibrium dialysis
Authors: Bigos S. Thomas , MacLean J. , Butler B. 
Published: May 2005

AbstractA study of 239 patients compared free thyroxine (FT4) measurements made by equilibrium dialysis (ED) with measurements made using the Magic Lite FT4 chemiluminescence (Cl) immunoassay (Ciba Corning Immunodiagnostics). Patient groups: 41 normals; 27 hyperthyroid; 29 hypothyroid; 37 sick euthyroid; 10 chronic renal failure (CRF) and 25 pregnant patients; 13 oestrogen; 10 heparin; 12 salicylate; and 9 dilantin‐treated patients; 3 lipaemic; 5 haemolysed; 6 hyperbilirubinaemic patients; 6 low thyroid binding protein (TBP) and 6 high TBP level patients. The two assays gave comparable results in most groups. Both assays tended to give elevated values in heparinized patients but FT4–ED results were more obviously affected. Pregnant patients and women on oral oestrogen had higher mean values with FT4–ED. In both assays the sick euthyroid and CRF patients had mean FT4 values similar to healthy euthyroid patients; the range of values in sick euthyroid and CRF patients was similar in both assays but wider than in healthy euthyroid patients. A supplemental study of 81 unselected acutely ill patients using FT4–Cl alone confirmed the wider range of values to be anticipated in sick euthyroid patients.
The chromophore of pholasin: A highly luminescent protein
Authors: Müller T. , Campbell A. K. 
Published: May 2005

AbstractPholasin is the photoprotein extracted from the marine bivalve Pholas dactylus. It undergoes an oxidative chemiluminescent reaction to oxypholasin with superoxide anion, hypochlorite, peroxidases and other oxidants. Since the observed absorbance and chemiluminescent emission spectra of pholasin solutions cannot be brought about solely by the amino acids composing the protein, there has to be a chemiluminescent chromophore. However, little is known about the chemical nature of this molecule. This work seeks to identify the chemical structure of the luminescent prosthetic group of pholasin.Pholasin could not be reactivated using chromophores from the hydroid Obelia geniculata (coelenterazine) and from the ostracod shrimp Vargula (formerly Cypridina) hilgendorfi. Furthermore, the reaction product of the Vargula chromophore could not be detected in solutions containing oxypholasin. Fluorescence analysis of such a solution revealed a compound with an emission spectrum (γmax 480 nm; excitation at 320 nm), resembling the emission spectrum of the chemiluminescent reaction. This fluorescent substance was separated by gel filtration. It exhibited an apparent molecular mass of < 2000. Fluorescence masurements of extracts of partially purified pholasin suggested that a flavin moiety may be involved in pholasin luminescence.
Chemiluminescence of bronchoalveolar lavage cells as an indicator of leukocyte activation in rats with a hyperreactive bronchus
Authors: Linssen M. , Wilhelms O.‐H. 
Published: May 2005

AbstractActivation and generation of inflammatory mediators by different leukocytes may be important in the pathogenesis of airway hyperreactivity. We studied the effect of active sensitization with ovalbumin as antigen and i.v. treatment with Sephadex particles on bronchial reactivity (BR) in rats and its possible relation to leukocyte infiltration (LI) and activation (LA) in bronchoalveolar lavage (BAL).A marked BR to aerosols of serotonin (5‐HT) and ovalbumin was found in Sephadex treated animals but not in control animals. In parallel to this a marked increase in BAL cell count from Sephadex‐treated animals compared to controls was seen. This increase in BAL cell count corresponded with a clear augmentation of spontaneous, buffer‐induced and C3Z‐induced, luminol‐amplified CL.We deduce that detection of CL of BAL cells from rats might be used for studying inflammatory mechanisms which lead to a hyperreactive bronchus.
Control of the lux regulon of Vibrio fischeri
Authors: Shadel G. S. , Devine J. H. , Baldvvin T. O. 
Published: May 2005

AbstractRegulation of expression of bioluminescence from the Vibrio fischeri lux regulon in Escherichia coli is a consequence of a unique form of positive feedback superimposed on a poorly defined cis‐acting repression mechanism. The lux regulon consists of two divergently transcribed operons. The leftward operon contains only a single gene, luxR, which encodes a transcriptional activator protein. The rightward operon contains luxl, which together with luxR and the 218 base pairs separating the two operons comprises the primary regulatory circuit, and the five structural genes, luxC, luxD, luxA, luxB and luxE, which are required for the bioluminescence activity. Transcription of luxR from PL is stimulated by binding of the E. coli crp gene product to the sequence TGTGACAAAAATCCAA upstream of the presumed promoter. Binding of pure E. coli CAP protein in a cAMP‐ dependent reaction to the V. fischeri lux regulatory region has been demonstrated by in vitro footprinting. The luxl gene product is an enzyme which catalyses a condensation reaction of cytoplasmic substrates to yield the autoinducer, N‐(3‐oxo‐hexanoyl) homoserine lactone. Accumulation of autoinducer, which is freely diffusible, results in formation of a complex with LuxR. The complex binds to the sequence ACCTGTAGGATCGTACAGGT upstream of PR to stimulate transcription of the rightward operon. Increased transcription from PR should yield increased levels of Luxl and higher levels of autoinducer which would further activate LuxR. The LuxR binding site is also a LexA binding site, as demonstrated by in vitro footprinting. Basal transcription from both PL and PR is repressed by sequences within the luxR coding region. Hence there appear to be at least two effects resulting from the interaction between LuxR: autoinducer and the control region DNA. One effect is to relieve the repression afforded by the sequences within luxR and the second is to stimulate transcription from PR. Recent analysis of the rightward promotor by site‐directed mutagenesis has suggested a different location for PR than that which was implicated in earlier studies. Our results suggest that the −35 sequence is located at a position which overlaps the 3′ edge of the LuxR binding site by one base pair.
Luc genes: Introduction of colour into bioluminescence assays
Authors: Wood Keith V. 
Published: May 2005

AbstractLuminescence assays are generally based on measurements of light intensity alone. Inclusion of colour as an additional parameter of the assay could increase the information content. Colour variation in luminescence is particularly prevalent among beetle luciferases. To study the relationship between enzyme structure and colour, luciferases from a Jamalcan click beetle were examined as a model system. These luciferases emit light ranging from green to orange, though their amino acid sequences differ by less than 5%. Through mutation of their respective cDNA clones, the amino acids responsible for the colour variation were identified. These specific amino acids are few, and they act upon colour independently with respect to the enzyme structure. Analysis of their effects indicates that the potential for colour variation among beetle luciferases is greater than is evident among the click beetle luciferase. Because of the subtle changes of enzyme structure that effect colour, luciferases that emit different colours may be useful as paired genetic reporters. They should interact equivalently with the intracellular environment of a host, but could be distinguished by colour in their assay. Such paired reporters could be used to observed simultaneous events, or to provide internal control for luminescence measurements.
In vivo bioluminescence: A cellular reporter for research and industry
Authors: Jassim S. A. A. , Ellison A. , Denyer S. P. , Stewart G. S. A. B. 
Published: May 2005

AbstractThe detection of specific bacterial pathogens, indicator microorganisms and antimicrobial substances, and the recovery of microorganisms from sub‐lethal injury, are all aspects of importance to industry which are currently being targeted using in vivo bioluminescence. In all instances, a key requirement for the application of bioluminescence is the establishment of a strict correlation between in vivo bioluminescence and cell viability, as determined by colony counting on agar plates. Comparative studies for biocides (phenol, chlorhexidine diacetate, phenol thioether), for a virucide (hypochlorite) and for cellular recovery of S. typhimurium from sub‐lethal injury, all indicate that such a correlation is valid. Furthermore, real‐time measurements of in vivo bioluminescence reveal a major population of bacterial cells that retain functional intracellular biochemistry, but are defective in their ability to replicate post of freeze injury.
CCD imaging of luciferase gene expression in single mammalian cells
Authors: Hooper Claire E. , Ansorge R. E. , Browne Helena M. , Tomkins Patricia 
Published: May 2005

AbstractQuantitative and sensitive imaging of chemiluminescence, bioluminescence and fluorescence emissions is emerging as an increasingly important technique for a range of biomedical applications (Hooper et al., 1990). A brief review of low‐light‐level imaging is presented, with particular reference to charge‐coupled devices (CCD). Detectors for sensitive imaging are described and compared, including various CCDs and photoncounting devices. Image analysis techniques based on digital image processing, may be applied to quantify luminescent processes with these detectors. Images of luciferase gene expression in single mammalian cells have been obtained using a particular highsensitivity intensified CCD camera. The method is illustrated using cell monolayers infected with recombinant vaccinia virus encoding the firefly luciferase, luc gene (Rodriguez et al., 1988). The CCD camera has been used to detect luciferase expression in single, recombinant infected cells amongst over one million non‐infected cells. The rapid detection of luciferase‐expressing viruses may be used for the selection of virus deletion mutants into which the luciferase gene has been cloned at specific sites. This is particularly useful in the case of viruses such as cytomegalovirus which have slow replication cycles.This direct imaging technique is simple and versatile. It offers a rapid, non‐invasive method for the sensitive detection of luciferase activity in single, luciferase‐expressing cells. One can envisage the use of luciferase as a sensitive and convenient co‐selection marker gene in the analysis of both gene expression and protein function. These methods offer tremendous potential in the fields of molecular and cellular biology.
Whole blood luminol‐enhanced chemiluminescence: Statistical analysis of the responses of different subjects
Authors: Ristola M. , Repo H. 
Published: May 2005

AbstractWhole blood luminol‐enhanced chemiluminescence (CL) was studied using N‐formyl‐methionyl‐leucyl‐phenylalanine (FMLP) or opsonized zymosan particles as stimuli. The peak and the integral responses of CL were recorded. In the FMLP‐induced CL the initial activation (1‐minute values) was also studied, because it coincides with the extracellular production of oxy radicals. Correction factors based on neutrophil count and on haemoglobin concentration were found to decrease dispersion and shape the distributions of the CL responses close to normal in a study of 50 healthy adults. One‐minute values were significantly lower in women than in men but there were no significant differences for peak or integral values between sexes. Depressed reaction is in accordance with the previous findings that phagocytic oxy radical production is depressed in female plasma. Thus, our results suggest that 1‐minute value is a variable more sensitive than peak or integral value of the CL response.
Enhanced chemiluminescence in the measurement of proteins and haptens: Evaluation of choriogonadotropin (hCG) and free thyroxin
Authors: Bonini P. A. , Banfi G. , Murone M. 
Published: May 2005

AbstractWe evaluated the Amerlite system (Amersham, Bucks, UK) for hCG and FT4. The within‐run imprecision (CV%) for hCG was 4.05 at 19.6 U/I (n = 10), 6.28 at 43.45 U/I (n = 10) and 4.62 at 298.57 U/I (n = 10). The between‐run imprecision (five replicates for ten days) was 4.8%, 15% and 11%, respectively. The system was linear up to 200 U/I. A good correlation between Amerlite hCG and an IRMA assay (Becton Dickinson, r = 0.91), Delfia (Pharmacia, r = 0.91) and an automated ELISA assay on ES 600 (Boehringer, r = 0.92) was observed on 70 samples.Within‐run imprecision for FT4 was 3.8% at 0.7 ng/dl (n = 10), 3.3% at 1 ng/dl (n = 10) and 4.32% at 5.15 ng/dl (n = 10), and between‐run was 5.95%, 4.4% and 8.2%, respectively. The comparison with a commercial direct RIA (Becton Dickinson) showed good correlation (r = 0.90, n = 100 samples). The diagnostic value of the association of thyrotropin and FT4, in comparison with the traditional thyroid tests (T3, T4, thyrotropin, FT4, FT3) has been assessed in various thyroid diseases.
Analysis of synchronous photon emissions from the bacterium Photobacterium phosphoreum during colony formation from a single cell
Authors: Watanabe Haruo , Suzuki Sohkichi , Kobayashi Masaki , Usa Masashi , Inaba Humio 
Published: May 2005

AbstractLight emission from Photobacterium phosphoreum was analysed during cell growth on an agar plate from a single cell to colony formation. Temporal analysis of image intensified light was set so that a quadratic window covered a single cell. Intensity of light emission from a single cell through colony formation showed an initial decrease, a prolonged lag phase, and then a rapid increase. These responses on an agar plate were similar to those from liquid cultures. The image analysis showed repeated bursts of light emission in the phases when light was increasing and decreasing. Statistical analysis of light emission also emphasized the presence of bursts of light emission, suggesting the metabolic synchronism of luciferase reactions in either a single cell or synchronously divided cells. The repetitive bursts of light occurred in a single cell and continued during the growth phase in which the cell population and the light emission was increasing. In a single cell, however, periodicity of light emission was not defined directly from fast Fourier transformation, although it was indicated on oscillation of mean level of fluctuated light emission, at initial phase of culture on agar plate.
Simultaneous measurement of endothelial cell damage, elastase release and chemiluminescence response during interaction between polymorphonuclear leukocytes and endothelial cells
Authors: Jonas Eleonore , Dwenger Alexander , Lueken Britta , Boehme Ulrich 
Published: May 2005

AbstractUsing cultured human umbilical cord vein endothelial cells and human blood neutrophils, the interaction between neutrophils and endothelial cells, in vitro, was studied. The aim of the study was to examine whether a respiratory burst stimulation by neutrophils would be observed by neutrophil/endothelial cell interaction and whether the respiratory burst stimulation of neutrophils by endothelial cells could be enhanced by lipopolysaccharide stimulation of neutrophils. The second aim was whether such an effect, or secretion of elastase, could cause an endothelial cell damage in vitro.Chemiluminescence as an indicator of oxygen‐derived metabolites produced by neutrophils, elastase release by neutrophils, and endothelial cell damage, based on111 In‐oxine release from labelled endothelial cells, were measured simultaneously. The present investigation demonstrates that neutrophils can be directly stimulated by endothelial cells. A further amplification of this process following lipopolysaccharide priming up to 10 ng/ml blood could be demonstrated. A slight endothelial cell damage occurs following neutrophil stimulation, although elastase secretion does not increase during interaction between neutrophils and endothelial cells. These results raise the possibility that oxygen‐derived metabolites rather than elastase contribute to an endothelial cell damage which might occur in conditions such as endotoxin‐induced adult respiratory distress syndrome.
Effect of different inhibitors on the intracellularly and extracellularly generated chemiluminescence induced by formylmethionyl‐leucyl‐phenylalanine in polymorphonuclear leukocytes. Cellular response in the presence of mannitol, benzoate, taurine, indomethacin and NDGA
Authors: Dahlgren Claes 
Published: May 2005

AbstractWhen polymorphonuclear leukocytes (PMNL) interact with the soluble stimulus formylmethionyl‐leucyl‐phenylalanine (FMLP), the cells increase their production of oxidative metabolites. This increased production can be measured as lumino‐amplified light emission or chemiluminescence (CL). In the present report, experimental systems which allow a quantitation of extracellularly and intracellularly generated metabolites have been used, and the effect of mannitol, benzoate, taurine, indomethacin and nordihydroguaiaretic acid has been investigated. The presence of the hypochlorous acid scavenger taurine had no effect on the intracellular response, whereas the extracellular response was reduced with around 50%. The hydroxyl radical scavenger mannitol had only minor effects on the response, whereas benzoate, another hydroxyl radical scavenger, reduced the extracellular response with around 50% and the intracellular response with more than 90%. Indomethacin, an inhibitor of arachidonic acid metabolism, did not influence the response, whereas NDGA, also an inhibitor of the arachidonic acid metabolism, totally abolished both the extracellular and the intracellular response. The use of scavengers/inhibitors as a means of determining the mechanisms of light emission, and the origin of chemiluminescence produced by neutrophils stimulated by FMLP is discussed.
The effect of serine and thiol protease inhibitors on the chemiluminescence of human neutrophils in investigations In Vitro
Authors: Kantorski J. , Tchórzewski H. 
Published: May 2005

AbstractWe have studied an indirect role of serine and thiol proteases in the activation of human neutrophils in vitro. Stimulation was evaluated using a chemiluminescence (CL) generation system. Receptor‐dependent and receptor‐independent stimuli were studied, e.g. opsonized zymosan, formyl‐methionyl‐leucyl‐phenylalanine, platelet activating factor, phorbol myristate acetate, and calcium ionophore A23187. The serine protease inhibitors TPCK and TLCK, and thiol protease inhibitor PHMB, diminished the CL with different potencies and in a dose‐dependent manner after treatment of cells with the various stimuli. Non‐specific serine protease inhibitor, PMSF, and trypsin substrate TAME, showed a low inhibitory potency with respect to CL generation. Synthetic substrates for chymotrypsin (BTEE, ATEE) significantly inhibited CL with the various stimuli used with some differences in susceptibility to their inhibition. Specific chymotrypsin inhibitors diminished both the resting and activator‐induced CL. We suggest that cell‐bound chymotrypsin‐like protease(s) is involved in the activation of signal transduction in human neutrophils after both receptor‐dependent and receptor‐independent stimulation.
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 1: Descriptions
Authors: Stanley Philip E. 
Published: May 2005

AbstractThis survey 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. More than 90 luminometers (manual, automatic, microtitre plate, HPLC, LC, GLC, imaging and specials) from more than 60 companies are included. Each company was invited to supply company brochures, technical details, user manual and information about software and any other information concerning their product(s). The response varied from a single information sheet to promotional material and up to full product information and specification with technical details, user manuals and scientific publications. Where an instrument is dedicated to a single task the company may have only provided details relevant to accomplishing that task. Part 2 of this survey will contain photographs of some of the luminometers. 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.
Influence of intracellular pH on light emission from a luxA/B derivative of Lactococcus lactis Subsp. diacetylactis
Authors: Simpson William J. 
Published: May 2005

AbstractHigh levels of constitutive aldehyde‐dependent light emission were obtained from non‐growing cells of Lactococcus lactis subsp. diacetylactis F712 transformed with luxA/B when they were suspended in buffered solutions. Inductions of light emission was time‐dependent and was not due to growth, synthesis of luciferase or stimulation of metabolism by fermentable carbohydrate. The major factor controlling light emission in such cells appears to be the intracellular pH value. Experiments with ionophores indicated that a transmembrane pH gradient was not essential for light emission.
Chemiluminescence of mononuclear cells is enhanced during antigen recognition
Authors: Tengler Rita S. , Furukawa Kazuhito , de Weck Alain L. , Maly Friedrich E. 
Published: May 2005

AbstractStimulation of phagocytes by several cytokines causes superoxide generation and consequently chemiluminescence. Since antigen‐activated lymphocytes generate cytokines, we investigated whether antigen recognition by mononuclear cells, which contain both lymphocytes and monocytes, is accompanied by changes in lucigenin‐dependent chemiluminescence. Mononulcear cells which underwent antigen‐induced proliferation showed a delayed rise in lucigenin‐dependent chemiluminescence in the absence of other stimuli. The common recall antigen Candida albicans increased spontaneous chemiluminescence of mononuclear cells from unselected donors up to 20‐fold over control values after 48–72h of culture. With Rabies virus vaccine as specific antigenic stimulus, only mononuclear cells from rabies immunized individuals responded with enhanced delayed chemiluminescence. In contrast to opsonized zymosan and phorbol myristate acetate, antigens induced no oxidative burst within one hour after addition. Delayed mononuclear cel chemiluminescence was inhibited by the superoxide scavenger superoxide dismutase and by di‐phenylene iodonium, a selective inhibitor of the phagocyte NADPH oxidase. A neutralizing monoclonal antibody against interferon‐gamma completely abrogated antigen‐induced chemiluminescence. Recombinant interferon‐gamma by itself induced delayed mononuclear cell chemiluminescence. Thus, antigen‐induced delayed mononuclear cell chemiluminescence represents activation of phagocyte NADPH oxidase by interferon‐gamma generated by activated lymphocytes.