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Featured researches published by Svein Simonsen.


Journal of The American Academy of Dermatology | 1999

Skin cancer in kidney and heart transplant recipients and different long-term immunosuppressive therapy regimens

Petter Jensen; Svein Hansen; Bjørn Møller; Torbjørn Leivestad; Per Pfeffer; Odd Geiran; Per Fauchald; Svein Simonsen

Abstract Background: Nonmelanoma skin cancer occurs frequently in organ transplant recipients, but the relative importance of different immunosuppressive therapy regimens is unclear. Objective: We studied the risk of skin cancer in the complete, single-center Norwegian cohort of kidney and heart transplant recipients (n = 2561). Methods: We determined cancer risk estimation by means of standardized incidence ratios and multivariate Cox regression. Results: Transplant recipients had an increased risk of cutaneous squamous cell carcinoma (SCC) (65-fold), malignant melanoma (3-fold), and Kaposis sarcoma (84-fold), and of lip SCC (20-fold), compared with the general population. After adjustment for age, kidney transplant recipients receiving cyclosporine, azathioprine, and prednisolone had a significantly (2.8 times) higher risk of cutaneous SCC relative to those receiving azathioprine and prednisolone. After adjustment for age and type of immunosuppressive regimen, heart transplant recipients had a significantly (2.9 times) higher risk than kidney transplant recipients. Conclusion: The risk of cutaneous SCC, malignant melanoma, Kaposis sarcoma, and lip SCC is increased in kidney and heart transplant recipients. The risk of posttransplant cutaneous SCC is related to the degree of immunosuppression caused by long-term immunosuppressive therapy. (J Am Acad Dermatol 1999;40:177-86.)


American Journal of Cardiology | 1999

Cytokine network in congestive heart failure secondary to ischemic or idiopathic dilated cardiomyopathy

Pål Aukrust; Thor Ueland; Egil Lien; Klaus Bendtzen; Fredrik Müller; Arne K. Andreassen; Ingvild Nordøy; Halfdan Aass; Terje Espevik; Svein Simonsen; Stig S. Frøland; Lars Gullestad

Inflammatory cytokines may play a pathogenic role in the development of congestive heart failure (CHF). Elevated circulating levels of inflammatory cytokines have been reported in CHF, but most studies have focused on only a few cytokine parameters. However, the activity of these cytokines are modulated by soluble cytokine receptors and cytokines with anti-inflammatory activities, and in the present study several of these interacting factors were examined simultaneously in 38 CHF patients with various degrees of heart failure and in 21 healthy controls. Patients with CHF had increased plasma concentrations of tumor necrosis factor (TNF)alpha, interleukin-6, soluble TNF receptors and the soluble interleukin-6 receptor, glycoprotein (gp)130. They also had elevated ratios of TNFalpha/soluble TNF receptors and interleukin-6/soluble gp130 as well as enhanced interleukin-6 bioactivity in serum, suggesting inflammatory net effects. In addition to raised circulating levels of inflammatory cytokines, CHF patients with severe heart failure also had abnormalities in the levels of anti-inflammatory cytokines, with decreased levels of transforming growth factor beta1 and inadequately raised interleukin-10 in relation to the elevated TNFalpha concentrations. This dysbalance between inflammatory and anti-inflammatory cytokines was also found in monocyte supernatants from CHF patients. The abnormalities in the cytokine network were most pronounced in patients with the most severe heart failure, and several of the immunologic parameters, in particular soluble gp130, were correlated with variables reflecting deranged hemodynamic status. The present study analyzing the complexity of the cytokine network in CHF, demonstrates profound disturbances in the levels of both inflammatory and anti-inflammatory mediators with a marked dysbalance favoring inflammatory effects.


Circulation | 1998

Elevated Circulating Levels of C-C Chemokines in Patients With Congestive Heart Failure

Pål Aukrust; Thor Ueland; Fredrik Müller; Arne K. Andreassen; Ingvild Nordøy; Halfdan Aas; John Kjekshus; Svein Simonsen; Stig S. Frøland; Lars Gullestad

BACKGROUND Immunologic and inflammatory responses appear to play a pathogenic role in the development of congestive heart failure (CHF). Activation and migration of leukocytes to areas of inflammation are important factors in these immunologic responses. Because the C-C chemokines are potent chemoattractants of monocytes and lymphocytes and can modulate other functions of these cells (eg, generation of reactive oxygen species), we measured circulating levels of three C-C chemokines in CHF. METHODS AND RESULTS Levels of macrophage chemoattractant protein-1 (MCP-1), macrophage inflammatory protein- 1alpha (MIP-1alpha), and RANTES (regulated on activation normally T-cell expressed and secreted) were measured by enzyme immunoassays in 44 patients with CHF and 21 healthy control subjects. CHF patients had significantly elevated levels of all chemokines with the highest levels in New York Heart Association class IV, and MCP-1 and MIP-1alpha levels were significantly inversely correlated with left ventricular ejection fraction. Elevated C-C chemokine levels were found independent of the cause of the heart failure, but MCP-1 levels were particularly raised in patients with coronary artery disease. Studies on cells isolated from peripheral blood suggested that platelets, CD3+ lymphocytes, and in particular, monocytes, might contribute to the elevated C-C chemokine levels in CHF. The increased MCP-1 levels in CHF were correlated with increased monocyte activity reflected in an enhancing effect of serum from CHF patients on O2-generation in monocytes, which was inhibited by neutralizing antibodies against MCP-1. CONCLUSIONS This first demonstration of increased circulating levels of C-C chemokines in CHF with particularly high levels in patients with severe disease may represent previously unrecognized pathogenic factors in CHF.


Circulation | 2005

Dysregulated Osteoprotegerin/RANK Ligand/RANK Axis in Clinical and Experimental Heart Failure

Thor Ueland; Arne Yndestad; Erik Øie; Geir Florholmen; Bente Halvorsen; Stig S. Frøland; Svein Simonsen; Geir Christensen; Lars Gullestad; P. Aukrust

Background—Persistent inflammation appears to play a role in the development of heart failure (HF). Osteoprotegerin (OPG), the receptor activator of nuclear factor-&kgr;B (RANK), and RANK ligand (RANKL) are newly discovered members of the tumor necrosis factor superfamily that are critical regulators in bone metabolism but appear also to be involved in immune responses. We hypothesized that the OPG/RANK/RANKL axis could be involved in the pathogenesis of heart failure (HF), and this hypothesis was investigated in both experimental and clinical studies. Methods and Results—Our main and novel findings were as follows: (1) In a rat model of postinfarction HF, we found persistently increased gene expression of OPG, RANK, and RANKL in the ischemic part of the left ventricle (LV) and, for OPG, in the nonischemic part that involved both noncardiomyocyte and in particular cardiomyocyte tissue. (2) Enhanced myocardial protein levels of OPG, RANK, and RANKL, in particular, were also seen in human HF, and using immunohistochemistry, we localized these mediators to cardiomyocytes within the LV in both experimental and clinical HF. (3) In human HF, we also found increased systemic expression of RANKL (T cells and serum) and OPG (serum), with increasing levels according to functional, hemodynamic, and neurohormonal disease severity. (4) RANKL increased total matrix metalloproteinase activity in human fibroblasts, which indicates a matrix-degrading net effect and suggests a potential mechanism by which enhanced RANKL expression in HF may contribute to LV dysfunction. Conclusions—These findings suggest a potential role for known mediators of bone homeostasis in the pathogenesis of HF and possibly represents new targets for therapeutic intervention in this disorder.


Cardiovascular Research | 2000

Myocardial expression of CC- and CXC-chemokines and their receptors in human end-stage heart failure

Jan Kristian Damås; Hans Geir Eiken; Erik Øie; Vigdis Bjerkeli; Arne Yndestad; Thor Ueland; Theis Tønnessen; Odd Geiran; Halfdan Aass; Svein Simonsen; Geir Christensen; Stig S. Frøland; Håvard Attramadal; Lars Gullestad; Pål Aukrust

OBJECTIVES Chemokines regulate several biological processes, such as chemotaxis, collagen turnover, angiogenesis and apoptosis. Based on the persistent immune activation with elevated circulating levels of chemokines in patients with congestive heart failure (CHF), we have hypothesised a pathogenic role for chemokines in the development of CHF. The objective of this study was to examine mRNA levels and cellular localisation of chemokines and chemokine receptors in human CHF. METHODS We examined explanted hearts from ten patients with end-stage heart failure (all chambers) and in ten organ donors using an RNase protection assays and immunohistochemical techniques. RESULTS Our main findings were: (i) expression of eight chemokine and nine chemokine receptor genes in both failing and nonfailing myocardium, (ii) particularly high mRNA levels of monocyte chemoattractant protein (MCP)-1 and CXC-chemokine receptor 4 (CXCR4), in both chronic failing and nonfailing myocardium, (iii) decreased mRNA levels of MCP-1 and interleukin (IL)-8 in the failing left ventricles compared to failing left atria, (iv) decreased chemokine (e.g., MCP-1 and IL-8) and increased chemokine receptor (e.g., CCR2, CXCR1) mRNA levels in failing left ventricles and failing left atria compared to corresponding chambers in the nonfailing hearts and (v) immunolocalisation of MCP-1, IL-8 and CXCR4 to cardiomyocytes. CONCLUSION The present study demonstrates for the first time chemokine and chemokine receptor gene expression and protein localisation in the human myocardium, introducing a new family of mediators with potentially important effects on the myocardium. The observation of chemokine dysregulation in human end-stage heart failure may represent a previously unknown mechanism involved in progression of chronic heart failure.


Cardiovascular Research | 2000

CXC-chemokines, a new group of cytokines in congestive heart failure — possible role of platelets and monocytes

Jan Kristian Damås; Lars Gullestad; Thor Ueland; Nils Olav Solum; Svein Simonsen; Stig S. Frøland; Pål Aukrust

OBJECTIVES The purpose of the present study was to examine the circulating levels of CXC-chemokines in patients with various degree of congestive heart failure (CHF). BACKGROUND CXC-chemokines may be important mediators in the persistent immune activation observed in CHF patients by activation of circulating neutrophils, T-cells and monocytes and possibly by the recruitment of these cells into the failing myocardium. METHODS Levels of interleukin (IL)-8, growth-regulated oncogene (GRO) alpha and epithelial neutrophil activating peptide (ENA)-78 were measured both in serum and in platelet-free plasma by enzyme immunoassay in 47 patients with CHF and in 20 healthy controls. RESULTS (i) CHF patients had significantly elevated levels of all the three CXC-chemokines with IL-8 and GRO alpha showing a gradual increase along with increasing NYHA class. (ii) There was an inverse correlation between IL-8 and left ventricular ejection fraction (EF) and cardiac index (CI). (iii) Both unstimulated and lipopolysaccharide (LPS)-stimulated monocytes from CHF patients released markedly elevated amounts of all three CXC-chemokines. (iv) Platelets from patients with severe CHF were characterised by decreased content of GRO alpha and ENA-78 as well as decreased release of these chemokines upon thrombin receptor stimulation. (v) Activated platelets stimulated peripheral blood mononuclear cells in vitro to enhanced release of IL-8, and neutralising antibodies against ENA-78 inhibited this interaction. CONCLUSIONS This study demonstrates for the first time elevated levels of CXC-chemokines in CHF, which may be of importance for progression of heart failure. Our findings further suggest that activated monocytes and platelets may contribute to enhanced CXC-chemokine levels in CHF.


Cardiovascular Research | 2003

Enhanced expression of inflammatory cytokines and activation markers in T-cells from patients with chronic heart failure.

Arne Yndestad; Are Martin Holm; Fredrik Müller; Svein Simonsen; Stig S. Frøland; Lars Gullestad; Pål Aukrust

OBJECTIVE Increasing evidence supports a role for inflammation in chronic heart failure (CHF). However, the source and the mechanism for this immune activation are unknown. To address this issue we investigated the gene expression of cytokines and the surface expression of activity markers in T-cells and monocytes from CHF patients and healthy controls. METHODS Gene expression of cytokines was analysed by real-time RT-PCR and activation markers by flow cytometry in 14 CHF patients and nine healthy controls. Surface expression of activation markers for T-cells and monocytes were analysed by flow cytometry. RESULTS T-cells from CHF patients showed enhanced gene expression of chemokines, ligands in the tumor necrosis factor superfamily, as well as the inflammatory cytokines interferon-gamma and interleukin-18 with similar pattern in ischemic (n=5) and idiopathic cardiomyopathy (n=9). In contrast, no differences in cytokine gene expression were found comparing monocytes from CHF patients and controls. Moreover, T-cells from CHF patients had enhanced surface expression of the activation markers CD69 and CD25, while there was no upregulation of the monocyte activation marker CD32 in these patients. CONCLUSION T-cells may be a part of the inflammatory response during CHF independent of the etiology of the disorder. Intervention preventing unwanted T-cell activation could represent a new target in the treatment of CHF.


Circulation | 2004

Elevated Levels of Activin A in Heart Failure Potential Role in Myocardial Remodeling

Arne Yndestad; Thor Ueland; Erik Øie; Geir Florholmen; Bente Halvorsen; Håvard Attramadal; Svein Simonsen; Stig S. Frøland; Lars Gullestad; Geir Christensen; Jan Kristian Damås; Pål Aukrust

Background—Although modulation of inflammatory processes has been suggested as a new treatment modality in heart failure (HF), our knowledge about abnormalities in the cytokine network during HF is still limited. On the basis of a previous cDNA array study examining peripheral blood mononuclear cells from HF patients, we hypothesized a role for activin A, a member of the transforming growth factor (TGF)-&bgr; superfamily, in the pathogenesis of HF. Methods and Results—This study had 4 main and novel findings. First, serum levels of activin A were significantly elevated in patients with HF (n=86) compared with healthy control subjects (n=20), with increasing levels according to disease severity as assessed by clinical, hemodynamic, and neurohormonal parameters. Second, compared with control subjects, HF patients, as determined by real-time quantitative reverse transcriptase polymer chain reaction, also had markedly increased gene expression of the activin A subunit activin &bgr;A in T cells but not in monocytes. Third, in a rat model of HF, we demonstrated a concerted induction of the gene expression of activin &bgr;A and activin receptors IA, IB, IIA, and IIB after myocardial infarction. Immunohistochemical analysis localized activin A solely to cardiomyocytes. Finally, activin A markedly increased gene expression of mediators involved in infarction healing and myocardial remodeling (ie, atrial natriuretic peptide, brain natriuretic peptide, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1, transforming growth factor-&bgr;1, and monocyte chemoattractant protein-1) in neonatal rat cardiomyocytes. Conclusions—Together with our demonstration of activin A–induced gene expression in neonatal cardiomyocytes of mediators related to myocardial remodeling, the expression pattern of activin A during clinical and experimental HF suggests an involvement of this cytokine in the pathogenesis of HF.


Journal of the American College of Cardiology | 2001

Enhanced gene expression of chemokines and their corresponding receptors in mononuclear blood cells in chronic heart failure—modulatory effect of intravenous immunoglobulin ☆

Jan Kristian Damås; Lars Gullestad; Halfdan Aass; Svein Simonsen; Jan Fjeld; Lisbeth Wikeby; Thor Ueland; Hans Geir Eiken; Stig S. Frøland; Pål Aukrust

OBJECTIVES We sought to study the gene expression of chemokines and their corresponding receptors in mononuclear blood cells (MNCs) from patients with chronic heart failure (CHF), both of which were cross-sectional and longitudinal studies during therapy with intravenous immunoglobulin (IVIg). BACKGROUND We have recently demonstrated that IVIg improves left ventricular ejection fraction (LVEF) in patients with CHF. Based on the potential pathogenic role of chemokines in CHF, we hypothesized that the beneficial effect of IVIg may be related to a modulatory, effect on the expression of chemokines and their receptors in MNCs. METHODS We examined: 1) the gene expression of C, CC and CXC chemokines and their receptors in MNCs from 20 patients with CHF and 10 healthy blood donors; and 2) the expression of these genes in MNCs from 20 patients with CHF randomized in a double-blind fashion to therapy with IVIg or placebo for 26 weeks. RESULTS Our main findings in CHF were: 1) markedly raised gene expression of macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and interleukin (IL)-8; 2) enhanced gene expression of their corresponding receptors; 3) modulation in a normal direction of this abnormal chemokine and chemokine receptor gene expression during IVIg, but not during placebo therapy; 4) down-regulation of MIP-1alpha, MIP-1beta and IL-8 during IVIg at the protein level in plasma; and 5) a correlation between down-regulation of MIP-1alpha gene expression and improved LVEF during IVIg therapy. CONCLUSIONS Our results further support a pathogenic role for chemokines in CHF and suggest that IVIg may represent a novel therapeutic approach, with the potential to improve LVEF in patients with CHF, possibly by modulatory effects on the chemokine network.


Journal of the American College of Cardiology | 2000

Restenosis and clinical outcome in patients treated with amlodipine after angioplasty: results from the Coronary AngioPlasty Amlodipine REStenosis Study (CAPARES).

Bjørn Jørgensen; Svein Simonsen; Knut Endresen; Kolbjørn Forfang; Karleif Vatne; James L. Hansen; John G. Webb; Christopher E. Buller; Gilles Goulet; Jan Erikssen; Erik Thaulow

OBJECTIVES Our intent was to investigate the effect of the dihydropyridine calcium channel blocker amlodipine on restenosis and clinical outcome in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND Amlodipine has sustained vasodilatory effects and relieves coronary spasm, which may reduce luminal loss and clinical complications after PTCA. METHODS In a prospective, double-blind design, 635 patients were randomized to 10 mg of amlodipine or placebo. Pretreatment with the study drug started two weeks before PTCA and continued until four months after PTCA. The primary angiographic end point was loss in minimal lumen diameter (MLD) from post-PTCA to follow-up, as assessed by quantitative coronary angiography (QCA). Clinical end points were death, myocardial infarction, coronary artery bypass graft surgery and repeat PTCA (major adverse clinical events). RESULTS Angioplasty was performed in 585 patients (92.1%); 91 patients (15.6%) had coronary stents implanted. Follow-up angiography suitable for QCA analysis was done in 236 patients in the amlodipine group and 215 patients in the placebo group (per-protocol group). The mean loss in MLD was 0.30 +/- 0.45 mm in the amlodipine group versus 0.29 +/- 0.49 mm in the placebo group (p = 0.84). The need for repeat PTCA was significantly lower in the amlodipine versus the placebo group (10 [3.1%] vs. 23 patients [7.3%], p = 0.02, relative risk ratio [RR]: 0.45, 95% confidence interval [CI]: 0.22 to 0.91), and the composite incidence of clinical events (30 [9.4%] vs. 46 patients (14.5%), p = 0.049, RR: 0.65, CI: 0.43 to 0.99) within the four months follow-up period (intention-to-treat analysis). CONCLUSIONS Amlodipine therapy starting two weeks before PTCA did not reduce luminal loss, but the incidence of repeat PTCA and the composite major adverse clinical events were significantly reduced during the four-month follow-up period after PTCA with amlodipine as compared with placebo.

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Lars Gullestad

Oslo University Hospital

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Odd Geiran

Oslo University Hospital

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Thor Ueland

Oslo University Hospital

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Einar Gude

Oslo University Hospital

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Pål Aukrust

Oslo University Hospital

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Satish Arora

Oslo University Hospital

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