Angiogenesis-independent cardioprotection in FGF-1 transgenic mice

OBJECTIVE: This study was performed to evaluate the cardioprotective role of acidic fibroblast growth factor-1 (FGF-1) in transgenic mice with cardiac-specific overexpression of human FGF-1. METHODS: Mice were subjected to coronary artery occlusion for 15-75 min with a continuously recorded 3-lead electrocardiogram (ECG). Infarct size was measured and ERK-1 and -2 activity was assessed by Western blot analysis. Creatine kinase and lactate dehydrogenase activity as marker for cell viability were measured in isolated ventricular myocytes subjected to simulated ischemia. RESULTS: Infarct development was markedly delayed in transgenics with first signs of myocardial infarction visible at 45 min after coronary artery occlusion compared to 15 min in wildtype. Maximal infarct size (60% of risk area) did not differ, but transgenics reached maximal infarction after 75 min compared to 45 min in wildtype animals. ECG revealed delayed Q-wave development and delayed ST-segment elevation in transgenics. Creatine kinase and lactate dehydrogenase release was significantly attenuated from isolated transgenic myocytes at 4 and 8 h after simulated ischemia. The delay in infarct development is partially due to a constitutive higher expression of the extracellular signal-regulated kinases ERK-1 and -2 in the myocardium of transgenics. Additionally, injection of the ERK-1/2 inhibitor UO126 decreased the cardioprotective effect of FGF-1. CONCLUSION: Cardiac specific overexpression of FGF-1 provides cardioprotection at the level of the cardiac myocyte, independent from angiogenesis, and at least partially mediated via activation of the mitogen activated protein kinase (MAP) ERK-1 and -2.     

Novel lymphocyte-independent mechanisms to initiate inflammatory arthritis via bone marrow-derived cells of Ali18 mutant mice

Objective. In a large-scale ENU (N-ethyl-N-nitrosourea) mousemutagenesis programme, we previously have identified and characterizeda novel mutation Ali18 that causes inflammatory arthritis likelesions in peripheral joints. In this study, we analysed theimmune system of Ali18 mice to understand mechanisms underlyingthe spontaneous inflammation. Methods. Humoral and cellular components of the immune systemwere phenotyped by ELISA and flow cytometry. The contributionof the immune system for phenotype expression was analysed indisease transfer experiments. The involvement of the adaptiveimmune system was investigated in Ali18;Rag1 double mutantsand the influence of environmental factors was analysed in Ali18mice reared under germ-free conditions. Results. Bone marrow cells from Ali18 mice were able to transferthe disease phenotype to naïve wild-type recipients suggestingthat cellular components of the reconstituted immune systemwere sufficient to induce arthritis. Ali18 mice revealed abnormalleucocyte populations including lymphocytes and granulocytes,as well as increased plasma IL-5 and IgE levels. Ali18;Rag1double homozygous mutants, which lack mature lymphocytes, stilldeveloped arthritis, suggesting that the phenotype is independentof the adaptive immune system. In addition, the arthritis phenotypeappeared to be independent from environmental conditions asdemonstrated in mice reared under germ-free conditions. Conclusions. The Ali18 mutation induces inflammatory arthritisthrough bone marrow-derived cells. However, non-pro-inflammatorycytokine cascades and mature lymphocyte independent-mechanismsare crucial for initiation and progression of the phenotype.Ali18 mice may thus represent a model to study mechanisms involvedin seronegative arthritis induced by cells of the innate immunesystem. KEY WORDS: Psoriatic arthritis, Animal model, Inflammatory arthritis, ENU, Mouse mutant Submitted 19 June 2007; revised version accepted 6 December 2007.     

Stent angioplasty of severe atherosclerotic ostial renal artery stenosis in patients with diabetes mellitus and nephrosclerosis.

Atherosclerotic renal artery stenosis (ARAS) may lead to deterioration of renal function or hypertension. The clinical outcome after stent angioplasty of ARAS on renal function and blood pressure control in patients with diabetes and nephrosclerosis is the subject of some controversy. We have analyzed the results of our single-center experience with stent angioplasty for severe (>/= 70%) ostial ARAS and present here the results of a subgroup analysis of those patients who had diabetes mellitus and nephrosclerosis. From 1996 to 2001, 241 patients underwent stent angioplasty for the treatment of ARAS at our center. Of these, 99 patients had diabetes mellitus (41%) and 176 patients (73%) had nephrosclerosis defined as intrarenal resistance index (RI) >/= 0.7 diagnosed by duplex ultrasound. All lesions (n = 355) were treated successfully. Mean blood pressure at baseline was comparable and significantly improved immediately after the intervention in all groups (nondiabetics: 102 +/- 12 to 93 +/- 10 mm Hg; diabetics: 102 +/- 14 to 93 +/- 11 mm Hg; RI < 0.7: 105 +/- 13 to 95 +/- 10 mm Hg; RI = 0.7-0.8: 100 +/- 12 to 92 +/- 10 mm Hg; RI > 0.8: 102 +/- 15 to 92 +/- 11 mm Hg; P < 0.0001 each). Baseline serum creatinine was not significantly lower in nondiabetics compared to diabetics (1.46 +/- 0.9 vs. 1.62 +/- 1.2 mg %; P < 0.05) and increased in patients with nephrosclerosis (RI < 0.7: 1.18 +/- 0.6 mg %; RI = 0.7-0.8: 1.57 +/- 1.1 mg %; RI > 0.8: 1.96 +/- 1.6 mg %). Except for patients without nephrosclerosis who had a normal baseline creatinine, serum creatinine decreased significantly in all subgroups during follow-up. Stent angioplasty of ARAS offers favorable acute and long-term clinical results for the preservation of the renal function and for blood pressure control in patients with diabetes mellitus and nephrosclerosis.     

Monophasic action potential mapping in human subjects with normal electrocardiograms: direct evidence for the genesis of the T wave

T wave concordance in the normal human electrocardiogram (ECG) generally is explained by assuming opposite directions of ventricular depolarization and repolarization; however, direct experimental evidence for this hypothesis is lacking. We used a contact electrode catheter to record monophasic action potentials (MAPs) from 54 left ventricular endocardial sites during cardiac catheterization (seven patients) and a new contact electrode probe to record MAPs from 23 epicardial sites during cardiac surgery (three patients). All patients had normal left ventricular function and ECGs with concordant T waves. MAP recordings during constant sinus rhythm or right atrial pacing were analyzed for activation time (AT) = earliest QRS deflection to MAP upstroke, action potential duration (APD) = MAP upstroke to 90% repolarization, and repolarization time (RT) = AT plus APD. AT and APD varied by 32 and 64 msec, respectively, over the left ventricular endocardium and by 55 and 73 msec, respectively, over the left ventricular epicardium. On a regional basis, the diaphragmatic and apicoseptal endocardium had the shortest AT and the longest APD, and the anteroapical and posterolateral endocardium had the longest AT and the shortest APD (p less than .05 to less than .0001). RT was less heterogeneous than APD, and no significant transventricular gradients of RT were found. In percent of the simultaneously recorded QT interval, epicardial RT ranged from 70.8 to 87.4 (mean 80.7 +/- 3.9) and endocardial RT ranged from 80 to 97.8 (mean 87.1 +/- 4.4) (p less than .001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of costs and safety of a suture-mediated closure device with conventional manual compression after coronary artery interventions.

The aim of this study was to assess costs and safety of immediate femoral sheath removal and closure with a suture-mediated closure device (Perclose, Menlo Park, CA) in patients undergoing elective (PCI). A total of 193 patients was prospectively randomized to immediate arterial sheath removal and access site closure with a suture-mediated closure device (SMC; n = 96) or sheath removal 4 hr after PCI followed by manual compression (MC; n = 97). In the SMC group, patients were ambulated 4 hr after elective PCI if hemostasis was achieved. In the MC group, patients were ambulated the day after the procedure. In addition to safety, total direct costs including physician and nursing time, infrastructure, and the device were assessed in both groups. Total direct costs were significantly (all P < 0.001) lower in the SMC group. Successful hemostasis without major complication was achieved in all patients. The time to achieve hemostasis was significantly shorter in the SMC group (7.1 +/- 3.4 vs. 22.9 +/- 14.0 min; P < 0.01) and 85% of SMC patients were ambulated on the day of intervention. Suture-mediated closure allows a reduction in hospitalization time, leading to significant cost savings due to decreased personnel and infrastructural demands. In addition, the use of SMC is safe and convenient to the patients.     

The SAVI-TF Registry: 1-Year Outcomes of the European Post-Market Registry Using the ACURATE neo Transcatheter Heart Valve Under Real-World Conditions in 1,000 Patients

Objectives

The SAVI-TF (Symetis ACURATE neo Valve Implantation Using Transfemoral Access) registry was initiated to study the ACURATE neo transcatheter heart valve in a large patient population treated under real-world conditions.