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E Fleck

Publications and source records attributed to E Fleck.

At least 109 records · Page 6Linked to original sources

[Differential reaction of human cardiac macro- and microvascular endothelial cells with respect to leucocyte adhesion and exposition to atherogenic lipoproteins].

While the cellular mechanisms of atherosclerosis have been intensively studied, the mechanisms leading to preferential localization of atherosclerotic lesions are less well understood. To further define these mechanisms, endothelial cells from coronary arteries, i.e., vessels with frequent atherosclerotic lesions, were isolated and grown in vitro. In order to compare the reactions of both cell types, endothelial cells derived from microvessels of human hearts were isolated and cultured under identical conditions. Incubation of endothelial cells with oxidized LDL (75 microg/ml protein) induced a significant increase in PAI-1 activity (182%, p < 0.05) in coronary macrovascular endothelial cells. This stimulatory effect of ox-LDL was less significant in microvascular endothelial cells (144%, p < 0.05). n-LDL did not influence secreted PAI-1 activity. Stimulation with angiotensin II induced expression of E-selectin more effectively in coronary macrovascular than in microvascular endothelial cells. In addition, angiotensin II-induced E-selectin expression led to increased E-selectin-dependent adhesion of HL60 cells to coronary macrovascular endothelial cells under flow conditions, while only little effect was observed with cardiac microvascular endothelial cells. In contrast, L-selectin-dependent adhesion, which has been shown to play an important role in inflammatory reactions, was preferentially observed in cardiac microvascular endothelial cells and could only be stimulated with TNFalpha, not by angiotensin II. Therefore, these cellular differences may in part explain specific properties of cardiac endothelial cells: Such that atherosclerotic lesions are localized in macrovascular vessel segments, whereas inflammatory responses are predominantly found in the microvasculature.

Cell Adhesion Molecules↗

Laser angioplasty of restenosed coronary stents: results of a multicenter surveillance trial. The Laser Angioplasty of Restenosed Stents (LARS) Investigators.

OBJECTIVES: This study evaluated safety and efficacy of excimer laser angioplasty for treatment of restenosed or occluded coronary stents. BACKGROUND: Balloon angioplasty of in-stent restenosis is limited by a high recurrence rate. Debulking by laser angioplasty is a novel concept to treat in-stent restenosis. METHODS: A total of 440 patients with restenoses or occlusions in 527 stents were enrolled for treatment with concentric or eccentric laser catheters and adjunctive balloon angioplasty. RESULTS: Laser angioplasty success (< or =50% diameter stenosis after laser treatment or successful passage with a 2.0-mm or 1.7-mm eccentric laser catheter) was achieved in 92% of patients. Adjunctive balloon angioplasty was performed in 99%. Procedural success (laser angioplasty success followed by < or =30% stenosis with or without balloon angioplasty) was 91%. There was neither a significant difference in success with respect to lesion length, nor were there differences between small and large vessels or native vessels and vein grafts. Success was higher and residual stenosis lower using large or eccentric catheters. Serious adverse events included death (1.6%, not directly laser catheter related), Q-wave myocardial infarction (0.5%), non-Q-wave infarction (2.7%), cardiac tamponade (0.5%) and stent damage (0.5%). Perforations after laser treatment occurred in 0.9% of patients and after balloon angioplasty in 0.2%. Dissections were visible in 4.8% of patients after laser treatment and in 9.3% after balloon angioplasty. Reinterventions during hospitalization were necessary in 0.9% of patients; bypass surgery was performed in 0.2%. CONCLUSIONS: Excimer laser angioplasty with adjunctive balloon angioplasty is a safe and efficient technology to treat in-stent restenoses. These data justify a randomized comparison with balloon angioplasty.

Adult↗

Validation of an accurate method for three-dimensional reconstruction and quantitative assessment of volumes, lengths and diameters of coronary vascular branches and segments from biplane angiographic projections.

UNLABELLED: The goal of the study was the validation of an accurate method for three-dimensional reconstruction and quantitative assessment of volumes, lengths and diameters of coronary vascular branches and segments from biplane angiographic projections. METHODS: The accuracy was tested in a complex phantom. In vivo, inter- and intraobserver agreement were assessed by analysis of routine angiograms. The sensitivity was evaluated using angiograms of patients having diagnostic vasoactive pharmacological intervention. Two-dimensional quantitative coronary angiography (2-D QCA) and 3-D QCA were compared concerning the accuracy of diameter evaluation. RESULTS: 3-D QCA yields accurate results (< 3% error) even based on nonorthogonal views, provided that projections parallel to the object are avoided. The inter- and intraobserver variability is < or = 5%. Significant (p < 0.01) changes of the volume (36-39%) and the diameter (19-21%) are detected following pharmacological intervention. 2-D QCA and 3-D QCA agree in short matched segments without foreshortening. 2-D QCA is rather sensitive to foreshortening and not suitable for evaluation of diameters of longer branches or total coronaries. CONCLUSION: 3-D QCA permits an accurate, reproducible and sensitive comprehensive three-dimensional geometric analysis of the coronaries and is superior to 2-D QCA with respect to extended diameter evaluation.

Algorithms↗

High fidelity correction of pressure signals from fluid-filled systems by harmonic analysis.

UNLABELLED: Fluid-filled systems are generally used for invasive pressure measurements in cardiology, anesthesiology and intensive care medicine. Wave reflection and attenuation cause considerable signal distortion. METHODS: The transducer signal is amplified (no filtering) and sampled (rate 1 kHz) using an autocorrelation based algorithm to detect instantaneous cycle length. A digital Fourier transformation (DFT) for each heart cycle is performed. Amplitude and phase distortion are corrected using data matrices determined in in vitro experiments or calibration measurements for each fluid-filled system to be used. As a measure for accuracy the maximum of the difference of reference and corrected pressures (DIFF) was selected. 960 analyses were performed to assess the impact of correction, used system, mean pressure, time and A/D sampling rate on the agreement with reference pressure. Clinical examples are presented. RESULTS: Mean pressure was correlated with DIFF (r = 0.83). The correction algorithm achieves a significant (p < 0.001) reduction of DIFF from 20-30 mm Hg to 0-5 mm Hg in the high pressure range and from 1-3 mm Hg to 0-1.5 mm Hg in the low pressure system in in vitro experiments and in clinical pressure recordings. Sampling frequency < 1 kHz reduces accuracy. CONCLUSIONS: High fidelity correction of pressure signals from fluid-filled systems by harmonic analysis is feasible.

Algorithms↗

Characterization of polymorphisms in the promoter of the human angiotensin II subtype 1 (AT1) receptor gene.

In this study eight sequence variants in the functional promoter of the human angiotensin II subtype 1 (AT1 or AGTR1) receptor gene are reported. Six of these variants are in nearly total linkage disequilibrium with each other and occur with a frequency of 15.7%. By haplotype estimation this group of eight sequence variants is characterized by only five haplotypes. There is no linkage disequilibrium between one of these haplotypes and the AT1 + 1166A/C variant. The finding of polymorphic sites in the functional promoter of the human AT1 locus will be beneficial to the study of the role of the AT1 receptor gene in hypertension and other cardiovascular diseases.

Base Sequence↗

Effects of lovastatin on progression of non-dilated and dilated coronary segments and on restenosis in patients after PTCA. The cholesterol lowering atherosclerosis PTCA trial (CLAPT).

OBJECTIVES: The Cholesterol Lowering Atherosclerosis PTCA Trial (CLAPT) is a prospective, randomized trial with blinded angiographic end-points to assess the effect of 2-year's treatment with lovastatin initiated 4 weeks prior to PTCA, compared to usual care on non-dilated coronary segments and on dilated coronary lesions in male patients with total cholesterol between 200 and 300 mg. dl(-1)who underwent elective PTCA. METHODS AND RESULTS: Two hundred and twenty six patients were randomized 4 weeks prior to PTCA to special care (diet plus lovastatin n=112) or usual care (diet; n=114). One hundred and ninety-nine patients underwent PTCA at baseline and were finally included in the study. Quantitative coronary angiographic assessment was performed on blinded cinefilms at baseline (PTCA) and repeated after 4 and 24 months in 91% and 81% of the patients. The primary end-point was a change in the mean segment diameter of non-dilated segments. The mean lovastatin dose was 33 mg. day(-1). Total- and LDL-cholesterol decreased by 21% and 29% in the special care group and by 7% and 11% in the usual care patients. After 2 years, the mean segment diameter of non-dilated segments decreased by 0.03 mm in the usual care group and 0.004 mm in the special care group (P=0.27). The decrease in the mean segment diameter of dilated lesions was 0.17 mm (usual care) and 0.06 mm (special care) (P=0.04) after 4 months; 0.16 mm (usual care) and 0. 002 mm (special care) after 24 months, respectively (P=0.05). In both groups, the mean segment diameter of dilated lesions increased between 4 and 24 months after PTCA compared to a decrease in mean segment diameter of non-dilated segments (P<0.05). Restenosis (>50% diameter stenosis at follow-up) occurred in 28.4% of usual care and 22.2% of special care patients (P=0.17). CONCLUSIONS: Lovastatin reduced the progression of dilated lesions in men with elective PTCA. Independent of treatment allocation, the dilated lesions regressed and the non-dilated segments progressed during the study follow-up. Four weeks of pre-treatment with lovastatin did not influence the rate of restenosis. Lovastatin had no statistically significant effect on non-dilated segments.

Angioplasty, Balloon, Coronary↗

PPAR gamma-ligands inhibit migration mediated by multiple chemoattractants in vascular smooth muscle cells.

The purpose of this study was to determine the effect of the peroxisome proliferator-activated receptor gamma-(PPAR gamma) ligands troglitazone (TRO), rosiglitazone (RSG), and 15-deoxy-delta prostaglandin J2 (15d-PGJ2) on vascular smooth muscle cell (VSMC) migration directed by multiple chemoattractants. Involvement of mitogen-activated protein kinase (MAPK) in migration also was examined, because TRO was previously shown to inhibit nuclear events stimulated by this pathway during mitogenic signaling in VSMCs. Migration of rat aortic VSMCs was induced 5.4-fold by PDGF, 4.6-fold by thrombin, and 2.3-fold by insulin-like growth factor I (IGF-I; all values of p < 0.05). The PPAR gamma ligands 15d-PGJ2, RSG, or TRO all inhibited VSMC migration with the following order of potency: 15d-PGJ2 > RSG > TRO. Inhibition of MAPK signaling with PD98059 completely blocked PDGF-, thrombin-, and IGF-I-induced migration. All chemoattractants induced MAPK activation. PPAR gamma ligands did not inhibit MAPK activation, suggesting a nuclear effect of these ligands downstream of MAPK. The importance of nuclear events was confirmed because actinomycin D also blocked migration. We conclude that PPAR gamma ligands are potent inhibitors of VSMC migration pathways, dependent on MAPK and nuclear events. PPAR gamma ligands act downstream of the cytoplasmic activation of MAPK and appear to exert their effects in the nucleus. Because VSMC migration plays an important role in the formation of atherosclerotic lesions and restenosis, PPAR gamma ligands like TRO and RSG, which ameliorate insulin resistance in humans, also may protect the vasculature from diabetes-enhanced injury.

Animals↗

Clinical evaluation of a prototype passive fixation dual chamber single pass lead for dual chamber ICD systems.

UNLABELLED: Dual chamber ICD systems use two separate leads for sensing. We developed and tested a new prototype of a single pass dual chamber passive fixation lead for dual chamber ICDs. METHODS AND RESULTS: The prototype was a modification of the Guidant CPI Endotak DSP lead. The additional sensing electrode for the right atrium consisted of a side-mounted porous atrial ring electrode (AR). Atrial signals were recorded from the lead in patients during normal sinus rhythm (NSR), atrial fibrillation (AFib), and/or atrial flutter (AFl) with the AR in stable contact with the atrial wall or floating. During NSR, with the AR in contact with the atrial wall, an average P wave amplitude of 7.2 +/- 1.5 mV (mean +/- SD, n = 12) was measured. After induction of Afib/AFl, the single amplitude decreased to 3.6 +/- 1.5 mV (n = 8) during AFib and 3.4 +/- 1.7 mV (n = 9) during AFl. Amplitudes dropped between 53% and 75% when the AR lost atrial wall contact. The atrial pacing threshold was 1.0 +/- 0.4 V (n = 16) when the AR was in contact with the atrial wall. CONCLUSIONS: In future dual chamber ICDs the signals from a passive fixation single pass lead could be used for atrial sensing and pacing as long as the sensing electrode for the right atrium remains in contact with the atrial wall. This system might lead to a simpler, less invasive implantation of dual chamber ICD systems.

Atrial Fibrillation↗

Effects of P2 purinoceptor agonists on membrane potential and intracellular Ca2+ of human cardiac endothelial cells.

Vasoactive agonists like adenosine-5'-triphosphate (ATP) increase intracellular Ca2+ ([Ca2+]i) in vascular endothelial cells with an initial peak due to inositol 1,4,5-triphosphate-mediated Ca2+ release from intracellular stores followed by a sustained plateau that is dependent on the presence of extracellular Ca2+, thus leading to an increased synthesis and release of prostacyclin and nitric oxide. We studied the effects of nucleotides on membrane potential and [Ca2+]i in confluent human microvascular cardiac endothelial cells obtained from patients with dilated cardiomyopathy. The whole-cell configuration of the patch-clamp technique and a confocal laser scanning microscope employing fluo-3 as a Ca2+ indicator were used. Both uridine-5'-triphosphate (UTP) and 2-methylthioadenosine-5'-triphosphate (2MeSATP) induced depolarizations in human microvascular cardiac endothelial cells and increased [Ca2+]i with a rank order of potency 2MeSATP>ATP=UTP (EC50 values (in microM) were 0.084 2MeSATP, 0.67 ATP and 1.1 UTP). This suggests that both P2u and P2y purinoceptors are present on human microvascular cardiac endothelial cells. Maximal [Ca2+]i responses of confluent human microvascular cardiac endothelial cell monolayers to UTP were lower when compared to 2MeSATP. Nucleotide-induced increases in [Ca2+]i consisted of a transient peak, which was also observed in the absence of extracellular Ca2+, and a sustained [Ca2+]i plateau. This plateau, which was not observed in all monolayers studied, was not markedly influenced by increasing extracellular [K+]. Previous incubation with thapsigargin abolished ATP-induced increases of [Ca2+]i. It is concluded that human microvascular cardiac endothelial cells express both P2y and P2u purinoceptors. P2 purinoceptor agonists release Ca2+ from intracellular thapsigargin-sensitive stores and stimulate capacitative Ca2+ influx pathways. K+ efflux through Ca2+-dependent K+ (K(Ca)) channels does not play a major role in the regulation of nucleotide-induced Ca2+ influx in human microvascular cardiac endothelial cells, which might be related to an impaired function of the cells.

Adenosine Triphosphate↗

Central role of the MAPK pathway in ang II-mediated DNA synthesis and migration in rat vascular smooth muscle cells.

Angiotensin II (Ang II) promotes vascular smooth muscle cell (VSMC) growth and migration, but the signaling pathways mediating these VSMC behaviors critical to restenosis and atherosclerosis are not completely known. The purpose of the present investigation was to define the role of mitogen-activated protein kinase (MAPK) in Ang II-induced DNA synthesis, migration, and c-fos induction in VSMCs. PD 98059, a synthetic inhibitor of MAPK kinase, or antisense oligodeoxynucleotides (ODNs) to deplete extracellular signal-regulated kinase (ERK)1 and ERK2 MAPKs, were used to inhibit MAPK signaling. PD 98059 at 30 micromol/L reduced Ang II-induced MAPK activity by 69% (P<0.01). Under these conditions, Ang II-induced DNA synthesis was completely inhibited (P<0.01), and Ang II-directed migration was attenuated by 76% (P<0.05). In contrast, induction of c-fos by Ang II was only partially suppressed (58% inhibition, P<0.01). Antisense ODNs against the initiation site of rat ERK1 and ERK2 MAPK mRNAs reduced corresponding protein levels by 63% (P<0.01) and completely inhibited MAPK activation by either Ang II (1 micromol/L) or 10% serum. Antisense ODNs (0.4 micromol/L) completely inhibited Ang II-induced DNA synthesis (P<0.01), decreased migration by 47% (P<0.01), and reduced c-fos induction by 40% (P<0.01 versus control ODN-transfected VSMCs). The Ang II type 1 (AT1)-receptor blocker irbesartan completely blocked DNA synthesis, migration, MAPK activation, and c-fos induction by Ang II in VSMCs. These results demonstrate that activation of MAPK plays a crucial role in Ang II-directed migration and DNA synthesis through the AT1 receptor. In contrast, Ang II-mediated c-fos induction and migration were only partially inhibited by either antisense ODNs or PD 98059, suggesting that other pathways in addition to the MAPK pathway may be involved in these actions of Ang II. We conclude that MAPK is a critical regulatory factor for Ang II-mediated migration and growth in VSMCs. Ang II-induced DNA synthesis showed a stronger MAPK dependence than did Ang II-directed migration or c-fos induction.

Angiotensin II↗

TNF-alpha-induced migration of vascular smooth muscle cells is MAPK dependent.

-Migration of vascular smooth muscle cells (VSMC) is a key event in neointimal formation and atherosclerosis that may be linked to the accumulation of inflammatory cells and release of chemotactic cytokines. Tumor necrosis factor-alpha (TNF-alpha) induces chemotaxis of inflammatory cells and fibroblasts, but little is known about chemotactic signaling by TNF-alpha in VSMC. The aim of this study was to investigate the role of TNF-alpha in VSMC migration and to elucidate the chemotactic signaling pathways mediating this action. TNF-alpha (50 to 400 U/mL) induced migration of cultured rat aortic VSMC in a dose-dependent manner. Because activation of the extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase (MAPK) is known to be required in platelet-derived growth factor-directed and angiotensin II-directed migration of these cells, we used the MAPK-inhibitor PD98059 to determine if chemotactic signaling by TNF-alpha involves the MAPK pathway as well. We found that TNF-alpha-directed migration was substantially inhibited by PD98059. TNF-alpha (100 U/mL) transiently activated MAPK with a maximal induction 10 minutes after stimulation that returned to baseline levels by 2 hours after treatment. Only a single peak of increased MAPK activity was seen. PD98059 also blocked TNF-alpha-stimulated MAPK activation in a concentration-dependent manner, which is consistent with its inhibition of TNF-alpha-directed migration. To identify which TNF-alpha receptor is involved in TNF-alpha-induced MAPK activation, antibodies against the p55 TNF-alpha receptor-1 (TNF-R1) and the p75 TNF-alpha receptor-2 (TNF-R2) were used. VSMC express both receptors, but TNF-alpha-induced MAPK activation was inhibited only by the TNF-R1 antibody. The TNF-R2 antibody had no effect. Thiazolidinediones are known to inhibit TNF-alpha signaling in adipose tissue and attenuate platelet-derived growth factor-directed and angiotensin II-directed migration in VSMC. We therefore investigated the effects of the thiazolidinediones troglitazone (TRO) and rosiglitazone (RSG) on TNF-alpha-induced migration. Both TRO and RSG inhibited migration, but neither attenuated TNF-alpha-induced MAPK activation, indicating that their antimigration activity was exerted downstream of MAPK. These experiments provide the first evidence that early activation of MAPK is a crucial event in TNF-alpha-mediated signal transduction leading to VSMC migration. Moreover, inhibition of TNF-alpha-directed migration by the insulin sensitizers TRO and RSG underscores their potential as vasculoprotective agents.

Analysis of Variance↗

Characterization of two distinct mechanisms for induction of apoptosis in human vascular endothelial cells.

Tissue homeostasis is fundamentally influenced by the functional integrity and state of endothelial cells. Survival and death of endothelial cells are encountered in cardiovascular disease and may, moreover, affect and determine the development of atherosclerosis and restenosis following intracoronary therapeutical interventions. Apoptosis was studied in cultured human umbilical vein endothelial cells (HUVEC) to investigate the regulation of endothelial cell death following serum/growth factor depletion as well as incubation with actinomycin-D. Apoptosis was verified by DNA fragmentation and quantified by fluorescence activated cell sorting (FACS) analysis after TdT-mediated deoxyuridine-triphosphate nick end-labeling (TUNEL). An ELISA was used for detecting intracytoplasmatic nucleosomes. Untreated HUVEC showed 16+/-6% TUNEL positive cells after 24 hours as analyzed by FACS. Serum/growth factor depletion increased apoptosis by 79+/-7%, while 50 ng/ml of the pro-apoptotic drug actinomycin-D induced comparable effects (72+/-11%). Apoptosis by serum/ growth factor depletion could be blocked completely by the anti-apoptotic agent cycloheximide (2 microg/ml), but was ineffective in blocking actinomycin-D-induced apoptosis. Pyrrolidine dithiocarbamate (PDTC) also acted as an anti-apoptotic agent by blocking apoptosis induced by actinomycin-D, but had no effect on apoptosis induced by factor depletion. Thus, two independent mechanisms for regulation of apoptosis are suggested to be present in human vascular endothelial cells.

Antioxidants↗

Screening the human bradykinin B2 receptor gene in patients with cardiovascular diseases: identification of a functional mutation in the promoter and a new coding variant (T21M).

To elucidate if genetic variants in the bradykinin B2 receptor (B2) gene occur that could affect receptor expression and function, we screened for mutations in the promoter and in the coding region of the human B2 gene. In our initial study we analyzed 92 consecutive, unrelated subjects (including 25 patients with hypertrophic cardiomyopathy, 18 patients with dilated cardiomyopathy (DCM), 25 patients with hypertension, 18 patients with coronary heart disease, and 6 patients with valvular heart disease) using nonradioactive polymerase chain reaction-single-strand conformation polymorphism analysis as mutation screening method. We detected eight as yet unknown polymorphic sites in the promoter region of the B2 gene (-845 C/T, -704 C/T, -649 insG, -640 T/C, -536 C/T, -412 C/G, -143 C/T and -78 C/T) with allele frequencies between 0.5 and 13%. One of them (-412 C/G) destroys a Sp1 binding site and abolishes protein binding to this Sp1 site in human umbilical vein endothelial cells and human vascular smooth muscle cells. In the protein-coding region one new coding variant (T21M) with the potential to create a truncated receptor isoform was detected. We determined the frequency of the promoter variant at position -412 (C --> G) and the newly identified coding variant (T21M) in extended samples of 69 patients with HCM, 163 patients with DCM, 109 patients with hypertension, and 173 healthy anonymous blood donors. The promoter variant (-412 C/G) was found in one blood donor and the T21M mutation was not found in the control population. Therefore, it appears that these mutations are rare events and the determination of clinical significance will be a demanding task in the future.

Cardiovascular Diseases↗

Randomized multicenter comparison of conventional anticoagulation versus antiplatelet therapy in unplanned and elective coronary stenting. The full anticoagulation versus aspirin and ticlopidine (fantastic) study.

BACKGROUND: Dual therapy with ticlopidine and aspirin has been shown to be as effective as or more effective than conventional anticoagulation in patients with an optimal result after implantation of intracoronary metallic stents. However, the safety and efficacy of antiplatelet therapy alone in an unselected population has not been evaluated. METHODS: Patients were randomized to conventional anticoagulation or to treatment with antiplatelet therapy alone. Indications for stenting were classified as elective (decided before the procedure) or unplanned (to salvage failed angioplasty or to optimize the results of balloon angioplasty). After stenting, patients received aspirin and either ticlopidine or conventional anticoagulation (heparin or oral anticoagulant). The primary end point was the occurrence of bleeding or peripheral vascular complications; secondary end points were cardiac events (death, infarction, or stent occlusion) and duration of hospitalization. RESULTS: In 13 centers, 236 patients were randomized to anticoagulation and 249 to antiplatelet therapy. Stenting was elective in 58% of patients and unplanned in 42%. Stent implantation was successfully achieved in 99% of patients. A primary end point occurred in 33 patients (13.5%) in the antiplatelet group and 48 patients (21%) in the anticoagulation group (odds ratio=0.6 [95% CI 0.36 to 0.98], P=0.03). Major cardiac-related events in electively stented patients were less common (odds ratio=0.23 [95% CI 0.05 to 0.91], P=0.01) in the antiplatelet group (3 of 123, 2.4%) than the anticoagulation group (11 of 111, 9.9%). Hospital stay was significantly shorter in the antiplatelet group (4.3+/-3.6 versus 6. 4+/-3.7 days, P=0.0001). CONCLUSIONS: Antiplatelet therapy after coronary stenting significantly reduced rates of bleeding and subacute stent occlusion compared with conventional anticoagulation.

Administration, Oral↗

Cloning and characterization of the 5'-flanking region of the human cardiotrophin-1 gene.

To enable the analysis of the regulation of the human cardiotrophin-1 gene expression, the 5'-flanking region of the human cardiotrophin-1 gene was cloned and sequenced. Data bank search revealed several cis- active DNA elements (SP1, CREB, C/EBP, AP1 and AP-2 like and GATA) in the proximal 1.1 kb region. Six nested 5-'terminal deletion mutants from -1091/+39 to -218/+39 were fused to a luciferase reportergene and proved to be functionally active after transfection into COS-7 cells.

Animals↗