A simple and rapid purification procedure minimizes spontaneous oxidative modifications of low density lipoprotein and lipoprotein (a).

Usual purification procedures of LDL and Lp(a) require numerous, extensive and prolonged sample handlings: this greatly increases the possibility of spontaneous oxidation. We have developed a method which, making use of two short-run ultracentrifugations in vertical rotors alternated by two rapid column-chromatography steps (SRUC), significantly shortens the preparation time to 3.5 h (LDL) and does not demand additional instrumentation or particular accuracy.

Decreased low-density lipoprotein oxidation after repeated selective apheresis in homozygous familial hypercholesterolemia.

Familial hypercholesterolemia was the first genetic disorder recognized to cause myocardial infarction. Patients with homozygous familial hypercholesterolemia have rapidly progressive coronary atherosclerosis with angina pectoris, myocardial infarction, or sudden death at a young age. Selective apheresis on dextran sulfate cellulose columns reduces mortality and may induce regression of coronary lesions.

Propafenone in the conversion of atrial fibrillation in patients suffering from chronic renal failure.

Propafenone is a class Ic agent for the treatment of atrial arrhythmias with a main hepatic metabolism. This approach might play an important role in the management of atrial arrhythmias in patients with chronic renal failure. The goal of this study was to investigate the effects of propafenone in patients with atrial fibrillation and chronic renal failure.

Glycosylation enhances oxygen radical-induced modifications and decreases acetylhydrolase activity of human low density lipoprotein.

Background: Posttranslational nonenzymatic glycosylation of native low-density lipoprotein (n-LDL) occurs both in vitro and in vivo in diabetic patients. Glycosylated LDL (glc-LDL) behave similarly to oxidized LDL in some respects. In fact, unlike n-LDL, uptake the glc-LDL can occur in part by the "scavenger" receptor(s), as also demonstrated for oxidized LDL.

Increased low-density lipoprotein peroxidation in elderly men.

Background: Oxidative modification of low-density lipoprotein (LDL) appears to play a pivotal role in atherogenesis. The specific role played by LDL peroxidation in aging is not known. Since estrogens may protect LDL from peroxidation in vitro and in vivo, we chose to investigate only men of various ages.

Effect of low density lipoprotein fatty acid composition on copper-induced peroxidation: 1H-nuclear magnetic resonance analysis.

Oxidation of low density lipoprotein (LDL) has been implicated in atherogenesis. An increased content of oleic acid in LDL and the substitution of monounsaturated for polyunsaturated fatty acids in the diet reduce LDL oxidation. With 1H-NMR analysis, all LDL modifications, including the production of copper-induced aldehyde products, can be evaluated simultaneously.

Long-term Treatment With Pravastatin Alone and in Combination With Gemfibrozil in Familial Type IIB Hyperlipoproteinemia or Combined Hyperlipidemia.

BACKGROUND: Pravastatin inhibits 3-hydroxy-3-methylglutaryl-coenzyme A reductase. It prevents mevalonate synthesis, reducing endogenous cholesterol production, and reduces cholesterol content in the liver, thus resulting in a down-regulation of low-density lipoprotein receptor production. Gemfibrozil reduces very low-density lipoprotein production and low-density lipoprotein-cholesterol level and increases very low-density lipoprotein catabolism.

Prevalence of peripheral arterial disease in an elderly rural population of southern Italy.

Blood pressure was measured at the posterior tibial artery by Doppler ultrasonography in 440 elderly subjects (205 men and 235 women) living in a rural community of Southern Italy, together with the evaluation of traditional risk factors for cardiovascular disease. An ankle/arm systolic pressure ratio below 0.90 was considered as a definite pathological sign of peripheral arterial disease (PAD).

High prevalence of myocardial ischemia and vasoconstrictive hormonal release in hypertension during chronic renal failure.

Objective: Indexes of myocardial ischemia and vasoconstrictive hormonal release were evaluated in order to investigate the difference between essential hypertension and hypertension during chronic renal failure.

Background: Arterial hypertension induces several cardiovascular alterations that reflect themselves either on the heart and/or on the coronary blood flow enhancing the cardiovascular risk. Since chronic renal failure can influence the neuroendocrine response, various mechanisms involved in hypertension during chronic renal failure are still unclear.

Relations between vasoactive hormones and diastolic function in hypertensive uraemic patients.

Background: Arterial hypertension is a significant risk factor for the high rate of cardiovascular disease in chronic uraemic (CU) patients. Any role that hypertension may play in CU patient outcomes assumes added significance. The elevation of some hormonal factors in early clinical stage could represent a valuable marker of cardiac disease in CU.

Calcium-channel blockers inhibit human low-density lipoprotein oxidation by oxygen radicals.

Previous studies have shown that calcium channel blockers may reduce the development of experimental atherosclerosis, and that nifedipine may slow the progression of coronary atherosclerosis in humans. The mechanisms responsible for this antiatherogenic effect are still unclear. It has been recently proposed that oxygen free radicals can induce the oxidation of human low-density lipoproteins (LDL) and that oxidized LDL may be an atherogenic stimulus.

The role of aging on the control of contractile force by Na(+)-Ca2+ exchange in rat papillary muscle.

Background: Sarcolemmal Na(+)-Ca2+ exchange system is believed to be fundamental to the control of cardiac contractility. However, the relation between Na(+)-Ca2+ exchange and the control of contractile force has not been studied in senescent myocardium.

Methods: The role of Na(+)-Ca2+ exchange in the regulation of the cardiac muscle's contractile force was studied in adult and senescent papillary muscles by simultaneously measuring intracellular sodium activity (aNai), action potential, and contractile force while varying extracellular concentration of sodium and/or calcium.

Chalcone synthase cosuppression phenotypes in petunia flowers: comparison of sense vs. antisense constructs and single-copy vs. complex T-DNA sequences.

Flower pigmentation patterns were scored in 185 sense Chalcone synthase (Chs) transgenotes and 85 antisense Chs transgenotes; upon first flowering, 139 (75%) of sense transgenotes were found to be phenotypically altered, as were 70 (82%) of the antisense transgenotes. The observed patterns document the range of phenotypic variations that occur, as well as confirm and extend the finding that sense Chs constructs produce several types of morphology-based flower pigmentation patterns that antisense Chs constructs do not. Long-term monitoring for epigenetic variations in one population of 44 sense Chs transgenotes showed that 43 (98%) were capable of producing a cosuppression phenotype.

Ergonomic approach in aging: experimental procedures to assess cognitive and balance impairments.

This brief commentary is focused on the experimental procedures employed in the evaluation of both cognitive and balance impairments of aging patients. This is an important ergonomic issue that might be used for research purposes. In fact, the corrected assessment of impairments during aging may favor the development of new integrated ergonomic strategies to ameliorate ADL together with the reduction of environmental risks.

Highly Branched Phenotype of the Petunia dad1-1 Mutant Is Reversed by Grafting.

The recessive dad1-1 allele conditions a highly branched growth habit resulting from a proliferation of first- and second-order branches. Unlike the wild-type parent, which has lateral branching delayed until the third or fourth leaf node distal to the cotyledons, dad1-1 initiates lateral branching from each cotyledon axil. In addition to initiating lateral branching sooner than the wild type, dad1-1 sustains branching through more nodes on the main shoot axis than the wild type.

[LDL oxidation in homozygous familial hypercholesterolemia: effects of selective LDL-apheresis treatment].

Homozygous familial hypercholesterolemia (HFH) results from a mutation affecting both the structure and function of a cell surface receptor that removes low density lipoproteins (LDL) from plasma. The disorder is characterized by autosomal dominant inheritance, a lifelong elevation in the concentration of LDL-bound cholesterol in blood and by cholesterol deposits that form xanthomas and early coronary artery disease. HFH patients, as a result of the increased levels and prolonged residence time of LDL in plasma, have a strong tendency toward accumulation of LDL-cholesterol in the arterial wall causing premature atherosclerosis.

Oxidative structural modifications of low density lipoprotein in homozygous familial hypercholesterolemia.

Patients with homozygous familial hypercholesterolemia (FH), as a result of the increased levels and prolonged residence time of low density lipoprotein (LDL) in plasma, have a strong tendency toward accumulation of LDL-cholesterol in the arterial wall, causing premature atherosclerosis. This phenomenon may enhance per se the physiological degradation of both protein and lipid component of LDL, which be more susceptible to oxidative damage induced by oxygen radicals. It is well known that LDL may undergo oxidative modification before being taken up by macrophages which are then transformed into foam cells.

Gaschromatography-mass spectrometry analysis of fatty acids in human milk from forty puerperae living in southern Italy.

Fatty acid (FA) composition of breast milk, an important factor in newborn nutrition, may change in relation to maternal diet and individual metabolic characteristics. This study was carried out on a group of 40 puerperae who lived in Southern Italy, delivered at term and feeded with common mediterranean diet. End-milk samples were collected between the 15th and 40th day (in mean at 27th day) after delivery.

Hyperlipidaemia and atherosclerotic cerebrovascular disease.

Controversies exist concerning the role of hypercholesterolaemia as a risk factor for nonhaemorrhagic stroke because intracranial arteries seem to be more resistant than coronary arteries to cholesterol-induced endothelial damage. Only very high levels of serum cholesterol seem to be a significant risk factor. It is possible that coronary heart disease may occur earlier in life than cerebrovascular atherosclerosis, and it could then become the cause of stroke.

Oxygen radicals inhibit human plasma acetylhydrolase, the enzyme that catabolizes platelet-activating factor.

Platelet-activating factor (PAF) can exert profound inflammatory effects at very low concentrations. In plasma, PAF is hydrolyzed to lyso-PAF by acetylhydrolase, an enzyme that circulates bound to LDL. Previous studies suggest that oxygen radicals may act synergistically with PAF to potentiate tissue injury.

[The peroxidation of human glycosylated low-density lipoproteins is mediated by the superoxide radical: the protective effects of superoxide dismutase].

Low-density lipoproteins (LDL) oxidized by oxygen radicals are a potent atherogenic stimulus. Chemically modified LDL are internalized by macrophages via a specific cell surface receptor that was termed the scavenger receptor, and could induce foam cell transformation. Post-translational nonenzymatic glycosylation of low density lipoprotein (LDL) occurs in vivo in diabetic patients.

Atrial natriuretic factor and sympathetic activation in human heart failure.

The neurohormonal changes occur early, have important prognostic value, and may play a role in the evolution and progression of heart failure in man. Atrial natriuretic factor (ANF) is a natriuretic and vasorelaxant peptide. Previous studies indicated that plasma ANF provides prognostic information and, ANF levels closely related to both severity of disease and catecholamine levels but, it is still unclear if high circulating levels of ANF, which are present in heart failure constantly, may be to correlate with sympathetic nervous activity in man.