Electron and immuno-electron microscopy of abdominal fat identifies and characterizes amyloid fibrils in suspected cardiac amyloidosis.

We evaluated the role of electron microscopy and immuno-electron microscopy studies on abdominal fat fine-needle biopsy samples in diagnosis and characterization of cardiac amyloidosis. The series consists of 15 patients with echocardiographic evidence of "restrictive cardiomyopathy" suspected to be due to amyloidosis. Patients underwent: clinical examination, electrocardiography, 2-D and Doppler echocardiography, immunofixation of serum and urine for detection of monoclonal immunoglobulins, and abdominalfat biopsies that were investigated with polarized light (Congo red), electron and immuno-electron microscopy using specific antibodies to kappa and lambda light chains, apolipoprotein A1, serum amyloid A (SAA), and transthyretin (TTR). Ultrastructural study of abdominal fat samples identified amyloid deposits in 15/15 cases. Immuno-electron microscopy specifically stained amyloid fibrils with antibodies anti-lambda (n = 8), -kappa (n = 2), -apolipoprotein A1 (n = 2) and -TTR (n = 3). Immuno-electron microscopy revealed TTR immuno-labelling in 2 patients with accidental monoclonal components, and a A reaction in I patient without monoclonal components. TTR and apolipoprotein A1 positive cases carried missense mutations in the corresponding genes. Our results demonstrate that amyloid deposits are present in the abdominalfat of patients suspected to have cardiac amyloidosis and that immuno-electron microscopy was able to characterize the amyloid protein in all cases.     

Interleukin 8 in serum in granulocytopenic patients with infections

Serum levels of interleukin 8 (IL-8) were examined in eight patients with acute myeloid leukaemia during 16 courses of chemotherapy. The patients experienced 14 episodes of fever which occurred in periods with granulocyte counts <0·5 × 10⁹/l. Febrile episodes were classified as bacteriologically defined infection ( n = 6), clinically defined infection ( n = 2), and unexplained fever ( n = 6). IL-8 was detected in 18/25 (72%), 2/3 (67%) and 3/7 (43%) of the serum samples in the respective groups. In contrast, IL-8 was detected in 22/90 (24%) of the samples taken when no fever was present ( P <0·00003 versus bacteriologically defined infection). The median concentration of IL-8 in samples taken during febrile episodes was 194 ng/ml (range 0–6358 ng/ml) and 0 (range 0–5392 ng/ml) on days without fever (not significant). In three patients with infections caused by, respectively, Streptococcus sanguis, Acinetobacter calcoanitratus and Candida albicans , IL-8 rose to a peak levels and declined during recovery. We conclude that IL-I is released systemically during infections with gram-positive and gram-negative bacteria and Candida albicans in patients with acute myeloid leukaemia and peripheral granulocytopenia due to chemotherapy. However, IL-8 can also be detected when no sign of infection is present.     

SHIP, SHIP2, and PTEN activities are regulated in vivo by modulation of their protein levels: SHIP is up-regulated in macrophages and mast cells by lipopolysaccharide

The phosphatidylinositol-3 kinase (PI3K) pathway plays a central role in regulating numerous biologic processes, including survival, adhesion, migration, metabolic activity, proliferation, differentiation, and end cell activation through the generation of the potent second messenger PI-3,4,5-trisphosphate (PI-3,4,5-P(3)). To ensure that activation of this pathway is appropriately suppressed/terminated, the ubiquitously expressed 54-kDa tumor suppressor PTEN hydrolyzes PI-3,4,5-P(3) to PI-4,5-P(2), whereas the 145-kDa hematopoietic-restricted SH2-containing inositol 5'-phosphatase SHIP (also known as SHIP1), the 104-kDa stem cell-restricted SHIP sSHIP, and the more widely expressed 150-kDa SHIP2 break it down to PI-3,4-P(2). In this review, we focus on the properties of these phospholipid phosphatases and summarize recent data showing that the activities of these negative regulators often are modulated by simply altering their protein levels. We also highlight the critical role that SHIP plays in lipopolysaccharide-induced macrophage activation and in endotoxin tolerance.     

Favourable effects of heart rate reduction with intravenous administration of ivabradine in patients with advanced heart failure

BACKGROUND: Heart rate (HR) reduction may be useful in treatment of patients with heart failure (HF). There are no data on the haemodynamic effects of ivabradine (a selective I(f) current inhibitor) in advanced HF patients. AIMS: To assess the haemodynamic effects of ivabradine in patients with advanced HF and markedly depressed left ventricular (LV) function. METHODS AND RESULTS: Ten NYHA class III patients (50+/-12 years, LV ejection fraction 21+/-7%) underwent 24-h haemodynamic monitoring. Ivabradine 0.1 mg/kg was infused over 90', followed by 0.05-0.075 mg/kg in the subsequent 90'. Baseline HR was 93+/-8 bpm, cardiac index (CI) 2.2+/-0.6 l/min*m2; LV stroke volume 44+/-11 ml and systolic work 39+/-13 g. Ivabradine significantly reduced HR, by a maximum of 27% (to 68+/-9 bpm) at 4 h, without decreasing CI. Ivabradine increased stroke volume and LV systolic work by a maximum of 51% (to 66+/-17 ml) and 53% (to 58+/-20 g) at 4 h. No serious adverse events occurred. CONCLUSION: In patients with advanced HF and markedly depressed LV function, the acute administration of ivabradine is well tolerated, effectively reduces HR, markedly increases stroke volume and preserves cardiac output. Ivabradine appears a promising approach for the treatment of patients with moderate and advanced heart failure.     

Influence of the degree of adherence to the mediterranean diet and its components on cardiometabolic risk during pregnancy. The GESTAFIT project

Background and aimsStudies regarding dietary patterns and cardiometabolic risk markers during pregnancy are scarce. The aim of the present study was to analyse whether different degrees of adherence to the Mediterranean diet (MD) and the MD components were associated with cardiometabolic markers and a clustered cardiometabolic risk during pregnancy.Methods and resultsThis study comprised 119 pregnant women from the GEStation and FITness (GESTAFIT) project. Dietary habits were assessed with a food frequency questionnaire at the 16th and 34th gestational weeks (g.w.). The Mediterranean Diet Score was employed to assess MD adherence. The following cardiometabolic markers were assessed: pre-pregnancy body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting glucose, triglycerides and high-density lipoprotein cholesterol (HDL-C). A greater MD adherence was associated with a better cardiometabolic status in cross-sectional (16th g.w. and 34th g.w.) and prospective analyses (MD adherence at the 16th g.w. and cardiometabolic markers at the 34th g.w.; SBP, DBP and HDL-C; all, p < 0.05). Participants with the highest MD adherence (Tertile 3) had a lower clustered cardiometabolic risk than those with the lowest MD adherence (Tertile 1) at the 16th and 34th g.w. (both, p < 0.05). A higher intake of fruits, vegetables and fish and a lower intake of refined cereals and red meat and subproducts were associated with a lower cardiometabolic risk during pregnancy (all, p < 0.05).ConclusionA higher MD adherence, a greater intake of fruits, vegetables and fish and a lower intake of refined cereals and red meat and subproducts showed a cardioprotective effect throughout gestation.     

Biochemical and aggregation analysis of Bence Jones proteins from different light chain diseases

Deposition of immunoglobulin light chains is a result of clonal proliferation of monoclonal plasma cells that secrete free immunoglobulin light chains, also called Bence Jones proteins (BJP). These BJP are present in circulation in large amounts and excreted in urine in various light chain diseases such as light chain amyloidosis (AL), light chain deposition disease (LCDD) and multiple myeloma (MM). BJP from patients with AL, LCDD and MM were purified from their urine and studies were performed to determine their secondary structure, thermodynamic stability and aggregate formation kinetics. Our results show that LCDD and MM proteins have the lowest free energy of folding while all proteins show similar melting temperatures. Incubation of the BJP at their melting temperature produced morphologically different aggregates: amyloid fibrils from the AL proteins, amorphous aggregates from the LCDD proteins and large spherical species from the MM proteins. The aggregates formed under in vitro conditions suggested that the various proteins derived from patients with different light chain diseases might follow different aggregation pathways.     

Diagnosis of antiphospholipid syndrome

Antiphospholipid syndrome is a multisystem autoimmune disease, characterized by recurrent vascular thrombosis and/or pregnancy losses in the presence of persistently positive antiphospholipid antibodies. In clinical practice, testing for anticardiolipin antibodies and lupus anticoagulant is mandatory for the laboratory diagnosis of antiphospholipid syndrome. Identification of patients with antiphospholipid syndrome is important, as prophylactic anticoagulant therapy may prevent thrombosis from recurring, and treatment during pregnancy can improve fetal and maternal outcome.     

LDL concentration is correlated with the removal from the plasma of a chylomicron-like emulsion in subjects with coronary artery disease

In animal model studies, the uptake of chylomicron remnants after entering in the space of Disse occurs mainly by low-density lipoprotein (LDL) receptor and LDL receptor-related protein (LRP). In subjects, the relative importance of each one of these receptors for the clearance of chylomicron remnants is not fully understood. In our study, LDL cholesterol and apolipoprotein (apo) B were correlated to the plasma kinetics of a chylomicron-like emulsion in 77 subjects (11 women, mean age 58 +/- 12 years) with coronary artery disease (CAD). Their total cholesterol was 227 +/- 25 mg/dl, triglyceride 159 +/- 25 mg/dl, LDL cholesterol 148 +/- 27 mg/dl, HDL cholesterol 40 +/- 9 mg/dl, apo A1 1.80 +/- 0.53 g/l and apo B 1.65 +/- 0.48 g/l. The emulsion was double-labeled with 3H-triolein and 14C-cholesteryl oleate and injected intravenously after 12-h fasting. The decay curves of the radioisotopes were determined from blood samples collected at predetermined intervals during 60 min. A negative correlation between FCR of the emulsion cholesterol esters and LDL cholesterol and apo B plasma concentrations was found (r=-0.4, P=0.005 and r=-0.3, P=0.01, respectively) whereas FCR of the emulsion triglycerides did not correlate with any of the plasma lipids or apolipoprotein parameters. Concluding, in patients with CAD, LDL catabolic pathway significantly influences the removal from plasma of chylomicron remnants.     

Validation of computed tomography image integration into the EnSite NavX mapping system to perform catheter ablation of atrial fibrillation

Introduction: The complex anatomy of the left atrium (LA) makes location of ablation catheters difficult using fluoroscopy alone, and therefore 3D mapping systems are now routinely used. We describe the integration of a CT image into the EnSite NavX System with Fusion and its validation in patients undergoing atrial fibrillation (AF) or left atrial tachycardia (AT) catheter ablation. Methods and Results: Twenty‐three patients (61 ± 9.2 years, 16 male) with paroxysmal (14) and persistent (8) AF and persistent (1) AT underwent ablation using CT image integration into the EnSite NavX mapping system with the EnSite Fusion Dynamic Registration software module. In all cases, segmentation of the CT data was accomplished using the EnSite Verismo segmentation tool, although repeat segmentation attempts were required in seven cases. The CT was registered with the NavX‐created geometry using an average of 24 user‐defined fiducial pairs (range 9 to 48). The average distance from NavX‐measured lesion positions to the CT surface was 3.2 ± 0.9 mm (median 2.4 mm). A large, automated, retrospective test using registrations with random subsets of each patient's fiducial pairs showed this average distance decreasing as the number of fiducial pairs increased, although the improvement ceased to be significant beyond 15 pairs. In confirmation, those studies which had used 16 or more pairs had a smaller average lesion‐to‐surface distance (2.9 ± 0.7 mm) than those using 15 or fewer (4.3 ± 0.8 mm, P < 0.02). Finally, for the 13 patients who underwent left atrial circumferential ablation (LACA), there was no significant difference between the circumference computed using NavX‐measured positions and CT surface positions for either the left pulmonary veins (178 ± 64 vs. 177 ± 60 mm; P = 0.81) or the right pulmonary veins (218 ± 86 vs. 207 ± 81 mm; P = 0.08). Conclusion: CT image integration into the EnSite NavX Fusion system was successful in all patients undergoing catheter ablation. A learning curve exists for the Verismo segmentation tool; but once the 3D model was created, the registration process was easily accomplished, with a registration error that is comparable with registration errors using other mapping systems with CT image integration. All patients went on to have subsequent successful ablation procedures. Where LACA was performed (13 patients), only four patients required segmental ostial lesions to achieve electrical isolation.