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Featured researches published by Steen Antonsen.


Scandinavian Cardiovascular Journal | 1987

NEUTROPHIL LYSOSOMAL ENZYME RELEASE AND COMPLEMENT ACTIVATION DURING CARDIOPULMONARY BYPASS

Steen Antonsen; Ivan Brandslund; Søren Clemensen; Søren Søfeldt; T. Madsen; Poul Alstrup

Complement activation and neutrophil degranulation were concomitantly studied during uncomplicated cardiopulmonary bypass (CPB). Plasma concentrations of complement factor C4, complement split product C3d, the neutrophil lysosomal enzyme elastase complexed with alpha 1-proteinase inhibitor (PI) and fibronectin were measured in 12 patients, C3d and elastase/PI increased significantly during CPB (volume-corrected results). The C3d rise was almost linear, whereas elastase/PI showed exponential increase. Mean elastase/PI and mean C3d concentrations at different times during CPB covaried closely. The study showed that during CPB neutrophil lysosomal enzyme release is intimately related to complement activation, although activation of the two systems may be caused by a common third activator within the extracorporeal circuit.


Scandinavian Journal of Clinical & Laboratory Investigation | 1993

An enzyme-linked immunosorbent assay for plasma-lactoferrin. Concentrations in 362 healthy, adult blood donors

Steen Antonsen; P. Wiggers; Jørgen Dalhøj; Ole Blaabjerg

Very different concentrations of plasma-lactoferrin in healthy adults have been reported in the literature. We compared three commercially available lactoferrins and lactoferrin purified in our laboratory as calibrators in an ELISA. No statistical differences among these preparations of lactoferrin were detected. The concentration of purified lactoferrin was measured by dry weight, and efforts were made in order to minimize loss of purified lactoferrin by adhesion to tubes etc. and thus, secure accuracy of the method. Dilutions were made in PBS 0.01 mol l-1 with NaCl 0.436 mol l-1, (NH4)2SO4 0.5 mol l-1, BSA 5 gl-1 and normal rabbit IgG 10 mg l-1, which was shown to give parallel dilution curves of primary calibrator, secondary calibrator and plasma samples. No significant difference in the content of lactoferrin in neutrophils (median; range) among men (1.78; 0.83-4.48 micrograms 10(-6) neutrophils; n = 20) and women (2.12; 1.16-9.30 micrograms 10(-6) neutrophils; n = 14) was found. Lactoferrin was analysed in EDTA-plasma obtained from 135 female and 227 male blood donors. Median concentrations were 84.7 and 97.8 micrograms l-1 respectively, while 2.5% and 97.5% reference limits (with 90% confidence intervals) were estimated to 42.9 (38.7-47.4) micrograms l-1 and 166.9 (151.0-186.3) micrograms l-1 for women and 52.3 (49.1-55.6) micrograms l-1 and 189.9 (175.9-206.4) micrograms l-1 for men, respectively.


Calcified Tissue International | 1991

Elevated serum levels of creatine kinase BB in autosomal dominant osteopetrosis type II

Jeppe Gram; Steen Antonsen; Mogens Hørder; Jens Bollerslev

SummarySerum levels of creatine kinase isoenzyme BB (CK-BB) were measured spectrophotometrically and by electrophoresis in 17 patients with autosomal dominant osteopetrosis (ADO) and compared with those of age- and sex-matched controls. Eight patients had ADO type I and nine patients had ADO type II. CK-BB was significantly increased (p<0.002) in type II but normal in type I compared with controls.This finding supports heterogeneity of ADO, and it may indicate a potential role for CK-BB as a marker of immature osteoclasts.


Scandinavian Journal of Clinical & Laboratory Investigation | 1993

An Elisa for elastase α1 -protease inhibitor complexes in human plasma and serum

Steen Antonsen; M. Wanscher

An Elisa for neutrophil elastase (ELA) in complex with ax-protease inhibitor (PI) (α1 -antitrypsin) was developed in microtitre plates and compared to the ELISA kit from MERCK (2-h version). Recovery of ELA-PI was good in both assays. The detection limits were 4.4μg1-1 and 7.7μg1-1 of the in-house and MERCK assay, respectively, while limits of quantitation were estimated to 7.7μg1-1 (5.5-9.9 μg1-1) and 28.9 μg1-1 (14.6-44.3 μg1-1) for the two assays. Furthermore, as dilution curves of normal plasma were parallel with the calibration curve in the in-house assay over a wide range of dilutions, it is feasible to assay plasma in dilutions of only 1: 6, resulting in a limit of quantitation of only 1.1 μg1-1. The total analytical coefficient of variation for samples measured in double determinations was 10.5%-12.5% in the in-house assay and 13.9%-14.6% in the MERCK assay. One-hundred-and-eight plasma samples covering a wide range of ELA-PI concentrations were analysed in both assays. A proportional difference b...


European Journal of Radiology | 1991

Influence of radiographic contrast media on granulocyte enzymes and complement during uncomplicated urographies

J. Georgsen; Finn Rasmussen; Steen Antonsen; Mogens Lytken Larsen

Four different radiographic contrast media (RCM) were used for i.v. urography in 40 patients, none of whom had complications. No rise in C3d was observed for any of the RCM, indicating that complement was not activated. However, significantly decreased values for CH50 were detected when the non-ionic RCM iopamidol and iohexol were used, and this may be due to interaction between the RCM and the complement molecules. Significantly increased numbers of neutrophils were observed in patients receiving ioxaglate, iohexol and diatrizoate, which may be due to inhibition of granulocyte adherence. No rise in the concentration of elastase and lactoferrin was observed. On the other hand, significantly decreased values of elastase were seen after injection of diatrizoate, which may be due to inhibition of the degranulation process by this media.


European Journal of Radiology | 1991

Granulocyte enzymes and complement after an anaphylactoid reaction to coronary angiography.

Finn Rasmussen; Steen Antonsen; J. Georgsen

An anaphylactoid reaction following angiography with ioxaglate in a 59-year-old man implied generalized pruritus, angioedema, bronchospasm and hypotension. Leucocytosis and an increased number of neutrophils were observed from 90 min to 8 h after the reaction. Elevated values of the neutrophil specific enzymes elastase and lactoferrin were demonstrated. The concentrations of C3d and CH50 did not change which indicate that no complement activation took place.


Scandinavian Journal of Clinical & Laboratory Investigation | 1989

In vitro granulocyte aggregation: Technical Note

Steen Antonsen; J. M. Beyer

Granulocyte aggregation in EDTA-blood from a patient with rheumatoid arthritis is described. The phenomenon was observed three times within a 10-month period. The blood leukocyte count in a Coulter Counter decreased approximately 30% within 6 h, without resulting in overt leukopenia. Simultaneously, increasing numbers of granulocyte aggregates turned up in smears. There were no indications of thrombocytes being involved in the phenomenon.


Scandinavian Journal of Clinical & Laboratory Investigation | 1989

Release of granulocyte elastase and complement changes during hysterectomy

M. Wanscher; F. Knudsen; Steen Antonsen; S. H. Hansen

Complement activation and release of granulocyte elastase has been previously reported during major vascular surgery and has been ascribed to plasma/cell interactions with foreign surfaces or to administration of blood or plasma. The effect of uncomplicated general anaesthesia and surgery, not requiring blood or plasma, on complement activation and signs of proteinase release was assessed by measuring C3d and elastase-alpha-1 PI, respectively, in nine patients undergoing elective hysterectomy. There was a minor decrease in plasma C3d during anaesthesia, surgery and in the post-operative period caused by the diluting effect of intravenous fluids. Elastase alpha-1 PI remained largely unchanged until the first post-operative day, when a significant increase was seen (p less than 0.05); on the second and third day significant elevated values were still observed. Release of granulocyte elastase seems to be a generalized response to surgical trauma and may be a part of the endocrine-metabolic stress response.


Scandinavian Journal of Clinical & Laboratory Investigation | 1993

Within-subject variation of elastase/α1-protease inhibitor complexes and lactoferrin in plasma

Steen Antonsen

Antonsen S. Within-subject variation of elastase/a!-protease inhibitor complexes and lactoferrin in plasma. Scand J Clin Lab Invest 1993; 53: 611-616.Several studies have shown increased plasma concentrations of neutrophil elas-tase in complex with a)-protease inhibitor and/or lactoferrin in inflammatory conditions, and serial measurements have been advocated in order to follow disease activity. However, data on the magnitude of the within-subject variation are necessary for evaluation of the significance of changes in results obtained on analysis of serial samples. Within-subject variation of elastase/oj)-protease inhibitor complexes and lactoferrin over a short time was studied in six young men who had blood samples drawn every 4h over 2 days. Within-subject variation over a longer time was investigated in 12 healthy adults, 6 females and 6 males, who had blood samples drawn in the morning once a week for 10 weeks. From five of the females and five of the males, blood samples were also drawn every morni...


Coronary Artery Disease | 2017

The association between uric acid levels and different clinical manifestations of coronary artery disease

Trine R. Larsen; Oke Gerke; Axel Cosmus Pyndt Diederichsen; Jess Lambrechtsen; Flemming Hald Steffensen; Niels Peter Sand; Lotte Saaby; Steen Antonsen; Hans Mickley

Aims Uric acid (UA) has been associated with the presence and severity of coronary artery disease. To further assess the role of UA role in coronary artery disease, we investigated UA levels in both healthy asymptomatic middle-aged individuals and in different subgroups of hospitalized patients with suspected or definite myocardial infarction (MI). Patients and methods The severity of coronary artery calcification (CAC) was examined in asymptomatic individuals (n=1039) using a noncontrast computed tomography scan. Hospitalized patients with suspected acute MI (n=772) were grouped according to troponin I (TnI) concentrations: (i) elevated TnI concentrations (>0.03 µg/l) with subdivision according to the type of MI and other clinical conditions associated with myocardial injury, or (ii) nonelevated TnI concentrations (⩽0.03 µg/l). Results UA was not associated with the severity of CAC in asymptomatic individuals when adjusting for relevant risk factors. Patients with type 2 MI and patients with myocardial injury associated with conditions of myocardial ischemia showed significantly higher UA levels (0.390 mmol/l, P=0.002 and 0.400 mmol/l, P=0.001, respectively) than patients with type 1 MI (0.329 mmol/l), after adjusting for other risk factors. Conclusion UA was not correlated with the severity of CAC in asymptomatic middle-aged individuals, and patients with type 2 MI or ischemic myocardial injury were shown to have higher UA levels than type 1 MI patients. This observation is concordant with the hypothesis that UA might be involved in the pathophysiological mechanisms leading to an imbalance in the oxygen supply/demand ratio in type 2 MI and ischemic myocardial injury.

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Anders Munck

University of Southern Denmark

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Hans Mickley

Odense University Hospital

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Jess Lambrechtsen

Odense University Hospital

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Niels Peter Sand

University of Southern Denmark

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