摘要:

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 autho

ISSN:0884-3996    

DOI:10.1002/bio.1170070302

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

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

ISSN:0884-3996    

DOI:10.1002/bio.1170070303

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

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 ofPhaseolus auresand decaying leaves ofEucalyptusare 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 regiont≤ 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 rep

ISSN:0884-3996    

DOI:10.1002/bio.1170070304

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractCommercially available crystalline native and recombinant firefly luciferases were compared. The two types of luciferase had indistinguishable responses to variation in ATP and luciferin concentrations and to omission of reaction components. The time courses of light production, the responses to nucleotide analogues, and the stability of the enzymes under several storage conditions were identical. The native enzyme had a slightly greater specific activity and was more sensitive to trypsin degradation. These differeces are probably attributable to differences in conformation.

ISSN:0884-3996    

DOI:10.1002/bio.1170070305

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

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 m

ISSN:0884-3996    

DOI:10.1002/bio.1170070306

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractIron controls luminescence inVibrio fischeriby an indirect but undefined mechanism. To gain insight into that mechanism, the involvement of cyclic AMP (cAMP) and cAMP receptor protein (CRP) and of modulation of DNA levels in iron control of luminescence were examined inV. fischeriand inEscherichia colicontaining the clonedV. fischeri luxgenes on plasmids. ForV. fischeriandE. coliadenylate cyclase (cya) and CRP (crp) mutants containing intactluxgenes (luxR luxlCDABEG), presence of the iron chelator ethylenediamine‐di (o‐hydroxyphenyl acetic acid) (EDDHA) increased expression of the luminescence system like in the parent strains only in thecyamutants in the presence of added cAMP. In theE. colistrains containing a plasmid with a Mu dl(lacZ) fusion inluxR, levels of β‐galactosidase activity (expression from theluxRpromoter) and luciferase activity (expression from theluxoperon promoter) were both 2‐3‐fold higher in the presence of EDDHA in the parent strain, and for the mutants this response to EDDHA was observed only in thecyamutant in the presence of added cAMP. Therefore, cAMP and CRP are required for the iron restriction effect on luminescence, and their involvement in iron control apparently is distinct from the known differential control of transcription from theluxRandluxlCDABEGpromoters by cAMP‐CRP. Furthermore, plasmid and chromosomal DNA levels were higher inE. coliandV. fischeriin the presence of EDDHA. The higher DNA levels correlated with an increase in expression of chromosomally encoded β‐galactosidase inE. coliand with a higher level of autoinducer in cultures ofV. fischeri. These results implicate cAMPCRP and modulation of DNA levels in the mechanism of iron control of theV. fischerilumi

ISSN:0884-3996    

DOI:10.1002/bio.1170070307

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0884-3996    

DOI:10.1002/bio.1170070308

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0884-3996    

DOI:10.1002/bio.1170070309

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0884-3996    

DOI:10.1002/bio.1170070301

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY