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Biomedical subjects

E Coni

Publications and source records attributed to E Coni.

18 recordsLinked to original sources
PubMed2001

Effects of dietary virgin olive oil phenols on low density lipoprotein oxidation in hyperlipidemic patients.

The aim of this study was to assess the effects of the dietary intake of extra virgin olive oil on the oxidative susceptibility of low density lipoproteins (LDL) isolated from the plasma of hyperlipidemic patients. Ten patients with combined hyperlipidemia (mean plasma cholesterol 281 mg/dL, triglycerides 283 mg/dL) consumed a low-fat, low-cholesterol diet, with olive oil (20 g/d) as the only added fat, with no drug or vitamin supplementation for 6 wk. Then they were asked to replace the olive oil they usually consumed with extra virgin olive oil for 4 wk. LDL were isolated at the beginning, and after the 4 wk of dietary treatment. LDL susceptibility to CuSO4-mediated oxidation was evaluated by measuring the extent of lipid peroxidation. We also determined fatty acid composition and vitamin E in plasma and LDL and plasma phenolic content. Extra virgin olive oil intake did not affect fatty acid composition of LDL but significantly reduced the copper-induced formation of LDL hydroperoxides and lipoperoxidation end products as well as the depletion of LDL linoleic and arachidonic acid. A significant increase in the lag phase of conjugated diene formation was observed after dietary treatment. These differences are statistically correlated with the increase in plasma phenolic content observed at the end of the treatment with extra virgin olive oil; they are not correlated with LDL fatty acid composition or vitamin E content, which both remained unmodified after the added fat change. This report suggests that the daily intake of extra virgin olive oil in hyperlipidemic patients could reduce the susceptibility of LDL to oxidation, not only because of its high monounsaturated fatty acid content but probably also because of the antioxidative activity of its phenolic compounds.

Adult↗
PubMed2000

Protective effect of oleuropein, an olive oil biophenol, on low density lipoprotein oxidizability in rabbits.

On the basis of the results obtained with pilot studies conducted in vitro on human low density lipoprotein (LDL) and on cell cultures (Caco-2), which had indicated the ability of certain molecules present in olive oil to inhibit prooxidative processes, an in vivo study was made of laboratory rabbits fed special diets. Three different diets were prepared: a standard diet for rabbits (diet A), a standard diet for rabbits modified by the addition of 10% (w/w) extra virgin olive oil (diet B), a modified standard diet for rabbits (diet C) differing from diet B only in the addition of 7 mg kg(-1) of oleuropein. A series of biochemical parameters was therefore identified, both in the rabbit plasma and the related isolated LDL, before and after Cu-induced oxidation. The following, in particular, were selected: (i) biophenols, vitamins E and C, uric acid, and total, free, and ester cholesterol in the plasma; (ii) proteins, triglycerides, phospholipids, and total, free, and ester cholesterol in the native LDL (for the latter, the dimensions were also measured); (iii) lipid hydroperoxides, aldehydes, conjugated dienes, and relative electrophoretic mobility (REM) in the oxidized LDL (ox-LDL). In an attempt to summarize the results obtained, it can be said that this investigation has not only verified the antioxidant efficacy of extra virgin olive oil biophenols and, in particular, of oleuropein, but has also revealed a series of thus far unknown effects of the latter on the plasmatic lipid situation. In fact, the addition of oleuropein in diet C increased the ability of LDL to resist oxidation (less conjugated diene formation) and, at the same time, reduced the plasmatic levels of total, free, and ester cholesterol (-15, -12, and -17%, respectively), giving rise to a redistribution of the lipidic components of LDL (greater phospholipid and cholesterol amounts) with an indirect effect on their dimensions (bigger by about 12%).

Animals↗
PubMed1999

Minor and trace element content of two typical Italian sheep dairy products.

The concentration ranges in milk and cheese of a number of metallic elements relevant to the health of the consumer are dependent upon animal species, feeding, time of year, environmental conditions and manufacturing processes. We have measured the concentrations of selected trace elements--Al, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Pt, Sr and Zn--in raw ewes' milk and typical ewes' milk cheeses. Samples of milk, curd, whey, cheese after moulding, cheese after salting, commercial cheese (Pecorino), Ricotta, scotta and brine were analyzed for seven complete cycles of cheese production. Samples of curd, whey, brine and waste product (i.e. scotta) were collected and analysed in addition to the cheese and milk to assess the distribution of each element in the main product, by-products and waste products during cheesemaking. Quantitative determinations were performed mainly by inductively coupled plasma atomic emission spectrometry. There were considerable differences among the trace element contents of raw ewes' milk and related products, indicating that manufacturing processes play a key role in the distribution of minor and trace elements. Two different approaches were used to assess the dietary intake of these elements associated with the consumption of Pecorino and Ricotta, and whether this had any nutritional or toxicological implications. The results indicated no toxicological risk and showed that, on the contrary, Pecorino may be a good source of several essential elements.

Animal Feed↗
PubMed1999

Tyrosol, the major olive oil biophenol, protects against oxidized-LDL-induced injury in Caco-2 cells.

Experimental and clinical evidence suggest that oxidative stress causes cellular damage, leading to functional alterations of the tissue. Free radicals may thus play an important role in the pathogenesis of a number of human diseases. Among pro-oxidant agents, oxidized LDL lead to the production of cytotoxic reactive species, e.g., lipoperoxides, causing tissue injury and various subsequent pathologies including intestinal diseases. Thus, to analyze the oxidative damage induced by oxidized LDL to intestinal mucosa, we evaluated morphological and functional changes induced in the human colon adenocarcinoma cell line, Caco-2. In addition, we examined the protective effects exerted by tyrosol, 2-(4-hydroxyphenyl)ethanol, the major phenolic compound present in olive oil. Caco-2 cell treatment (24 and/or 48 h) with oxidized LDL (0.2 g/L) resulted in cytostatic and cytotoxic effects characterized by a series of morphological and functional alterations: membrane damage, modifications of cytoskeleton network, microtubular disorganization, loss of cell-cell and cell-substrate contacts, cell detachment and cell death. The oxidized LDL-induced alterations in Caco-2 cells were almost completely prevented by tyrosol which was added 2 h before and present during the treatments. Our results suggest that some biophenols, such as those contained in olive oil, may counteract the reactive oxygen metabolite-mediated cellular damage and related diseases, by improving in vivo antioxidant defenses.

Analysis of Variance↗
PubMed1999

Antioxidant activity of 3,4-DHPEA-EA and protocatechuic acid: a comparative assessment with other olive oil biophenols.

Olive oil contains several phenolic compounds with antioxidant activity, whose levels depend strongly on the kind of cultivar grown, fruit ripening effects and the oil extraction process. Therefore, the beneficial effects exerted by olive oil consumption on the resistance of low density lipoproteins (LDLs) to oxidation depend not only on an increased intake of mono-unsaturated fatty acids (e.g. oleate) which are less prone to oxidation, but also phenolic antioxidants. The aim of this study was to analyze in vitro effects exerted on the oxidative modification of Cu-stimulated human LDL by two olive oil biophenols, i.e. 3,4-dihydroxyphenylethanol-elenolic acid (3,4-DHPEA-EA) and protocatecuic acid. These compounds have not been investigated in as much detail as the better-known olive oil biophenols - such as tyrosol (p-HPEA), o-coumaric acid, vanillic acid, caffeic acid, oleuropein and 3,4-dihydroxyphenylethanol (3,4-DHPEA). Modification of LDL was tested by measuring the formation of intermediate and end products of lipid peroxidation such as conjugated dienes, lipid hydroperoxides, cholesterol and cholesteryl ester oxides, as well as studying the decrease in oxidizable substrates like polyunsaturated fatty acids. In addition, the increase in LDL negative charges was evaluated. The results demonstrate the two-tested olive oil biophenols show high antioxidant activities. In particular, protocatecuic acid and 3,4-DHPEA-EA show an antioxidant activity comparable with that of caffeic acid, oleuropein and 3,4-DHPEA. They are not only able to retard lipid peroxidation, but also to reduce the extent of its activity.

Antioxidants↗
PubMed1995

[Handling of biological material before trace element determination].

The various steps of the analytical process are taken into account with particular reference to problems arising in sampling biological materials, their storage, pretreatment, digestion (when necessary) and determination. Emphasis is laid on the fact that the availability of analytical equipment with exceptional detection power is not always flanked by an equivalent ability to control phenomena of contamination and/or loss of analytes as well as to check and guarantee the accuracy of experimental data. In this context, proper use of the most popular analytical techniques for the determination of trace elements and the adoption of strict procedural conditions for data reliability are briefly discussed.

Animals↗
PubMed1994

A pilot study on colon cancer occurrence as related to serum selenium levels.

A pilot study was undertaken in order to assess the relationship between selenium status and occurrence of colon cancer in a selected population group. The opportunity for starting the programme occurred in 1992 after some information attained from health control laboratories that noted human colon cancer death rates much higher than normal in a well defined geographical area of central Italy (province of Terni). Element levels in serum and healthy and neoplastic colon tissues were determined for twenty subjects affected by the disease. A hydride generation-based method with inductively-coupled plasma atomic emission spectrometry (ICP-AES) detection was developed for the determination of Se in acid-digested samples. The mean values observed in the three types of samples led to the following conclusion: i) Se levels in serum of subjects affected by colon cancer are significantly lower (0.063 +/- 0.018 microgram/ml) than those reported previously for the national average (0.089-0.093 microgram/ml); ii) there is a considerable difference in Se levels between the healthy and neoplastic tissues (0.098 +/- 0.030 microgram/g vs 0.158 +/- 0.065 microgram/g).

Colonic Neoplasms↗
PubMed1993

Aluminium content of infant formulas.

An investigation was undertaken in order to assess Al concentration levels in infant formulas. Eligibility criteria were defined and strictly adhered to. An overall strategy was worked out to guarantee reliability and representativity of experimental data, in particular by minimizing all possible sources of chemical contamination or loss. The study was carried out by means of Inductively-Coupled Plasma Atomic Emission Spectrometry (ICP-AES). In cow's milk-based infant formulas as made up for consumption (about 13% in the final solution), Al levels of between 0.03-0.85 mg/L were detected. Higher amounts were present in soya-based formulas, with concentrations ranging from 0.39 to 1.01 mg/L.

Aluminum↗
PubMed1992

Cadmium intake with diet in Italy: a pilot study.

Data on Cd sources in food are presented and the effects are discussed of the raised environmental level of Cd concentration in some foods. Information is also presented on normal dietary intakes of this element and how these intakes may be increased by environmental pollution or atypical dietary habits. With reference to the exposure risk, the FAO/WHO has established for adults a Provisional Tolerable Weekly Intake (PTWI) limit of 7 micrograms/kg B.W.. Therefore the evaluation of dietary Cd intake has become very important. The purpose of this work is the estimation of dietary intakes of Cd using data on the composition of an average Italian diet. Complete meals from a factory canteen were analyzed and calculations of weekly intake of Cd carried out. Mean dietary intake was 222 micrograms per week (range 137-326 micrograms per week) or 32 micrograms per day (range 19-46 micrograms per day), with the median intake being 198 micrograms per week or 28 micrograms per day. Analyses were performed by means of Zeeman Electrothermal Atomization Atomic Absorption Spectrometry (ETA-AAS). The results obtained, related to the average and representative food consumption of Italian people, show that the weekly intake is well within the PTWI, but the emission of Cd into the environment is continuing and attention must be paid to population groups at risk due to particular food habits.

Cadmium↗
PubMed1990

Reference values for essential and toxic elements in human milk.

Dependable reference values (RVs) for the concentration ranges of health-related elements in human biological fluids and organs are to date of acknowledged importance for an early recognition of pathological states. On the other hand, the present lack of reliable data on levels to be considered as baseline values for elements of major concern from a toxicological, environmental and nutritional point of view demands the development of experimental procedures capable of satisfying the requirements of detection power, specificity and applicability on a large scale necessary to generate vast amounts of reliable measurements. As part of an overall monitoring program, an investigation was undertaken with the following two aims: a) the present suitability of inductively-coupled plasma atomic emission spectrometry (ICP-AES) to identify and quantitate minor and trace elements in human milk with the necessary accuracy and precision; b) assessment of RV concentrations for Al, Ba, Cd, Cr, Cu, Fe, Li, Mg, Mn, Ni, Pb and Zn. Four population groups were selected (each with 9 subjects) resulting from the various combinations of smokers and non-smokers from an urban or a rural environment. Strict eligibility criteria were adopted in order to select only women in good health, no known occupational exposure and whose nutritional habits could be described in detail. A scrupolous and systematic approach was adopted to minimize every possible source of elemental contamination from the sampling step onwards. Digestion of samples was attempted both with mixtures of strong acids and by resorting to acid-assisted mineralization in a microwave oven. Both methods were satisfactory for subsequent introduction into the torch of the ICP-AES system. The outcome of this pilot study gave the following median RVs for concentration (in mg/kg): Al, 0.14; Ba, 0.013; Cd, 0.002; Cr, 0.016; Cu, 0.40; Fe, 0.72; Li, 0.004; Mg, 29.4; Mn, 0.006; Ni, 0.05; Pb, 0.016; and Zn, 3.08.

Female↗
PubMed1990

Presence and assessment of xenobiotic substances in milk and dairy products.

The presence of some xenobiotics such as toxic metals, PCBs, pesticides and micotoxins in both human and cow milk as well as in dairy products is evaluated on the basis of currently available data. The problems hindering a thorough risk assessment for the said toxicants are highlighted. As regards elements, the results of a study carried out on three different classes of products, namely, bulk milk from various regions of Italy, milk from one particular farm and several types of cheese available to the public at large, are reported and discussed. Quantitative determinations of Cd, Cr, Cu, Pb and Zn have been carried out by means of graphite furnace absorption spectrometry.

Animals↗
PubMed1989

Selenium intake with diet in Italy: a pilot study.

Selenium is an element essential to man. The main environmental pathway of Se-exposure for the general population is through food. As is true for all essential elements, not only deficient but also excessive exposure results in adverse health effects. Between these extremes there is a range of safe and adequate Se intakes. In 1980 the Italian National Research Council recommended 50-200 micrograms/day as an interval adequate to meet nutritional requirements, being at the same time below the threshold of toxic effects. Therefore the evaluation of dietary Se intake has become very important. The purpose of this work is the estimation of dietary intakes of Se using data on the amount and composition of an average Italian diet. Complete meals from a factory canteen were analyzed and calculations of weekly intake of Se carried out. Analyses were performed by means of Inductively-coupled Plasma Atomic Emission Spectrometry. The results obtained, related to the average and indicative food consumption of Italian people, showed that the daily intake is well within the recommended range.

Diet↗
PubMed1989

Criteria for reference value assessment of elements in human tissues.

The availability of updated and reliable reference values for elements in biological tissues and fluids plays a key role in the correct planning and performance of clinical, toxicological and environmental studies. The basic principles for a proper analytical approach in order to obtain such data are outlined. This in turn should significantly reduce the wide range of figures reported for most elements as "normal" intervals in the scientific literature. Some applications of these guidelines are illustrated in detail in the case of human lungs, liver and kidneys for which tentative reference values are assessed for a number of minor and trace elements, namely, Al, Ba, Cd, Cr, Cu, Li, Mg, Mn, Pb, Sr, V and Zn.

Humans↗
PubMed1989

Determination of selenium in foods by inductively-coupled plasma atomic emission spectrometry and hydride generation.

Within the framework of a survey launched by the Istituto Superiore di Sanità to assess the average daily intake of Se with food in the Italian population, a preliminary study was carried out to develop an analytical procedure for the quantification of the element in food products. The method implies the use of a hydride generation system in combination with inductively-coupled plasma atomic emission spectrometry (ICP-AES) and exploits the inherent advantages of this last also for the analysis of non-metals. The overall approach was tested in some Hungarian and Italian foods, adequately lending itself to routine and reliable Se assay.

Food Analysis↗
PubMedDate not supplied

Inductively coupled atomic emission spectrometry and neutron activation analysis for the determination of element reference values in human lung tissue.

An investigation was undertaken in order to assess the performance of neutron activation analysis and inductively coupled plasma atomic emission spectrometry techniques for determining reference values for minor and trace elements in human lungs of urban subjects. Results show that in both instances experimental conditions must be carefully optimized to guarantee reliability of experimental data. Strict criteria for tissue sampling and pretreatment also had to be set. Provisional reference values for ca. 50 elements could thus be established.

Animals↗
PubMedDate not supplied

Effect of unbalanced diets on the long-term metabolism of a toxicant. 1. Lead in rats: preliminary note.

The aim of this study was the evaluation of the effect of dietary imbalances on absorption and distribution of lead in the female Sprague-Dawley rat. In this note preliminary results on the relationship between blood concentrations of lead and unbalanced diets are presented. Hyperproteic, hyperglycidic, hyperlipidic and balanced diets were prepared, and most of them included 15 mg/kg lead. Blood samples were collected at day 0, 21, 36, and 95 of the diets and analyzed by anodic stripping voltammetry (ASV). Lead uptake as a function of feed consumption was found to decrease in the order: balanced, hyperproteic and hyperglycidic, hyperlipidic diet. On the other hand lead blood levels were as follows (decreasing order): hyperlipidic, hyperproteic, hyperglycidic, balanced. Further research is being carried out on the influences of dietary imbalances on whole-body distribution of lead.

Absorption↗