Lipoprotein(a) Genotype Influences the Clinical Diagnosis of Familial Hypercholesterolemia

Background Evidence suggests that LPA risk genotypes are a possible contributor to the clinical diagnosis of familial hypercholesterolemia (FH). This study aimed at determining the prevalence of LPA risk variants in adult individuals with FH enrolled in the Italian LIPIGEN (Lipid Transport Disorders Italian Genetic Network) study, with (FH/M+) or without (FH/M-) a causative genetic variant. Methods and ResultsAn lp(a) [lipoprotein(a)] genetic score was calculated by summing the number risk-increasing alleles inherited at rs3798220 and rs10455872 variants. Overall, in the 4.6% of 1695 patients with clinically diagnosed FH, the phenotype was not explained by a monogenic or polygenic cause but by genotype associated with high lp(a) levels. Among 765 subjects with FH/M- and 930 subjects with FH/M+, 133 (17.4%) and 95 (10.2%) were characterized by 1 copy of either rs10455872 or rs3798220 or 2 copies of either rs10455872 or rs3798220 (lp(a) score >= 1). Subjects with FH/M- also had lower mean levels of pretreatment low-density lipoprotein cholesterol than individuals with FH/M+ (t test for difference in means between FH/M- and FH/M+ groups <0.0001); however, subjects with FH/M- and lp(a) score >= 1 had higher mean (SD) pretreatment low-density lipoprotein cholesterol levels (223.47 [50.40] mg/dL) compared with subjects with FH/M- and lp(a) score=0 (219.38 [54.54] mg/dL for), although not statistically significant. The adjustment of low-density lipoprotein cholesterol levels based on lp(a) concentration reduced from 68% to 42% the proportion of subjects with low-density lipoprotein cholesterol level >= 190 mg/dL (or from 68% to 50%, considering a more conservative formula). ConclusionsOur study supports the importance of measuring lp(a) to perform the diagnosis of FH appropriately and to exclude that the observed phenotype is driven by elevated levels of lp(a) before performing the genetic test for FH

Structure and Morphology of Silver Nanoparticles on the (111) Surface of Cerium Oxide

The structure of Ag nanoparticles of different size, supported on the cerium oxide (111) surface, was investigated by X-ray absorption fine structure at the Ag K-edge. The results of the data analysis in the near and extended energy range are interpreted with the help of the results obtained by X-ray photoelectron spectroscopy and scanning tunneling microscopy measurements and allow to obtain a detailed atomic scale description of the model system investigated. The Ag nanoparticles have an average size of a few tens of angstroms, which increases with increasing deposited Ag amount. The nanoparticles show a slight tendency to nucleate at the step edges between different cerium oxide layers and they have a face centered cubic structure with an Ag-Ag interatomic distance contracted by 3-4% with respect to the bulk value. The interatomic distance contraction is mainly ascribed to dimensionality induced effects, while epitaxial effects have a minor role. The presence of Ag-O bonds at the interface between the nanoparticles and the supporting oxide is also detected. The Ag-O interatomic distance decreases with decreasing nanoparticle size

Growth and study of Ni nanoparticles films deposited on inert subtrates

We report the results of a study on Ni-clusters assembled films deposited on Si(100) and MgO(100) surfaces. The films were produced by deposition of pre-formed Ni nanoparticles generated by a gas aggregation source. The samples topography and growth mode were investigated with SEM, AFM, STM and XPS. MOKE technique was used to determine magnetization curves at T=300 K, T=100 K and T=50K. The films show random paving growth mode, where clusters assemble in agglomerates. From MOKE data we observe a behaviour that can be ascribed to the occurrence of Super Correlated Spin Glass phase at T=300 K, and soft ferromagnetic hysteresis cycles at low temperature, possibly related with a different magnetic phase

Morphological and magnetic characterization of Ni nanoparticles films

We present the results of a study on the morphology and magnetic properties of size-selected Ni nanoparticles films grown on Si/SiOx substrates. The films were produced by deposition of preformed Ni nanoparticles, using a gas aggregation nanocluster source and an electric quadrupole mass filter. The diameter d of the produced particles ranged between 3 and 10 nm. The morphology of the films, with average thickness t varying from t=0.5 up to t=7 nm, was studied with atomic force microscopy and scanning electron microscopy, combining in this way information about height and lateral topography. We observed the presence of some small aggregates made of two or three particles at the early stage of film formation, probably due to some degree of cluster diffusion on the substrate, and particle average flattening. For increasing values of t, large agglomerates are formed in the films, resulting in a porous structure. Information about the magnetic properties was obtained with field cooled-zero field cooled FC/ZFC magnetization curves. We observed a reversibility-irreversibility transition at temperatures 70 KTI80 K, and a significant deviation from the superparamagnetic behavior at TTI, even for the lowest coverage studied t=2 nm for ZFC/FC measurements, d=5.5 nm. A comparison with Monte Carlo simulations of the FC/ZFC curves reveals the concurrence between interparticle exchange interaction and single particle magnetic anisotrop

Influence of Lifestyle Measures on Hypertriglyceridaemia

Hypertriglyceridaemia is a common dyslipidaemia encountered in clinical practice. People with hypertriglychypertriglyceridaemia are frequently obese, insulin-resistant, hypertensive or diabetic, all of which are risk factors for cardiovascular diseases. Hypertriglyceridaemia also contributes to metabolic syndrome, in which an atherogenic diet, sedentary lifestyle, overweight/obesity and genetic factors interact. A multi-factorial intervention for all risk factors is necessary, including weight reduction, dietary modification and increased physical exercise. This review focuses on the influence of diet, sedentary lifestyle and negative habits (such as excessive alcohol intake, smoking and drug addiction) on hypertriglyceridaemia as well as the effects of lifestyle change

Morphology and magnetic properties of size-selected Ni nanoparticle films

We present the results of a study on the morphology and magnetic properties of size-selected Ni nanoparticles films grown on Si/SiOx substrates. The films were produced by deposition of preformed Ni nanoparticles, using a gas aggregation nanocluster source and an electric quadrupole mass filter. The diameter d of the produced particles ranged between 3 and 10 nm. The morphology of the films, with average thickness t varying from t = 0.5 up to t = 7nm, was studied with Atomic Force Microscopy and Scanning Electron Microscopy, combining in this way information about height and lateral topography. We observed the presence of some small aggregates made of 2 o 3 particles at the early stage of film formation, probably due to some degree of cluster diffusion on the substrate, and particle average flattening. For increasing values of t, large agglomerates are formed in the films, resulting in a porous structure. Information about the magnetic properties was obtained with Field Cooled-Zero Field Cooled (FC/ZFC) magnetization curves. We observed a reversibility-irreversibility transition at temperatures 70 K TI, even for the lowest coverage studied (t = 2 nm for ZFC/FC measurements, = 5.5 nm). A comparison with Montecarlo simulations of the FC/ZFC curves reveals the concurrence between inter-particle exchange interaction and single particle random anisotropy

RELATIONSHIP BETWEEN SERUM URIC ACID AND METABOLIC SYNDROME IN THE BRISIGHELLA HEART STUDY COHORT

Objective: Classically correlated with pathologies such as kidney stone and gout, today serum uric acid (SUA) seem to play a pivotal role in the cardiovascular disease risk. SUA is also strongly related to metabolic syndrome (MS) and its components. The aim of our study was to evaluate the SUA cut-off associated to the highest probability to detect a MS Design and method: We selected from the general database of the Brisighella Heart Study a sample of non-pharmacologically treated adult subjects, in primary prevention for cardiovascular disease, without known allergic nor rheumatological disease, not assuming antioxidant dietary supplements, visited during the same population survey. The SUA cut-off associated to the highest probability to detect a MS was investigated creating specific receiver operating characteristic (ROC) curves. Results: In our study median SUA levels were significantly higher in men (5,1 mg/dL) than in women (3,6 mg/dL) (p < 0.05). Splitting our cohort in 2 groups on the basis of SUA medians,we obtained 2 very different populations: if SUA levels were over the median the main cardiovasculardisease risk factors means were higher, while HDL cholesterol and apolipoprotein A1 levels were lower; these patients were more frequently affected by MS (58,5%) and hypertension (52,7%) than those with SUA levels under the median. The ROC curves showed that the SUA levels was a predictive test for the identification of those people affected by MS, with an AUC similar between men and women (6,6 vs 6,8, respectively); the cut off, by the way, were 5,75 mg/dL in men and 3,95 mg/dL in women. SUA levels seems to be the main determinant of MS both in men (OR = 1,66; 95%CI 1,23 – 1,99) and women (OR = 1,63; 95%CI 1,19 – 1,97). Conclusions: In our cohort SUA is strongly related to MS diagnosis, also for level lower than those usually considered normal