[Membrane platelet fatty acids: biochemical characterisation of the ischemic cardiovascular disease, characteristics of the paediatric age, through an artificial neural network interpretation]. / Acidi grassi di membrana delle piastrine: tipizzazione biochimica della cardiopatia vascolare ischemica e caratteristiche dell'età pediatrica nell'interpretazione di una Rete Neurale Artificiale.

During the last 30 years, a huge research has been performed about the markers involved in the atherogenetic process and in the fatty acid thrombogenetic effect. More recently many studies have been made on the biochemical aspects of the saturated fatty acids with respect to the cardiovascular risk, in particular, the Stearic Acid (SA). Because of the peculiar characteristic of the platelets in the control of the thrombogenetic risk, we have investigated the platelet fatty acid profile in three groups of subjects: supposed healthy (n = 60), ischemic (n = 50), young children (n = 118). The aim of the study was to understand wich of the fatty acids could be evaluated as markers of the ischemic cardiovascular pathology and to have the possibility to classifie the subjects using the artificial neural network (ANN) system. The results highlight the peculiar position of the Oleic Acid, Linoleic Acid and Arachidonic Acid. According to the ANN results of the ischemic subjects, the young children were in the same position. Because this result is not commonly accepted, as children are healty, we have looked for a reason. There are well strong reasons to believe that all this is due to the stearic acid wich is extremely higher than the stearic acid of all the other subjects investigated. Particularly it has been underlined the possibility to modify the platelet stearic and oleic acid to obtain a better saturation index (Stearic/Oleic ratio). This could bring to a better control of the cardiovascular risk. It is possible, according with the results obtained, to open a new field of research on the lipid metabolism of the young children in relation to the atherogenesis. It is the first time that an observation on the platelet membrane phospholipid stearic acid is made in comparison to other adult subjects and a plausible explanation is given about the protection of the young children against the cardiovascular disease.

Sapid solutions and food intake in repeated dehydration and rehydration periods in rats.

In a previous report, it has been shown that water deprivation significantly affects the two-bottle taste preferences and one-bottle taste acceptance in rats when no food was available during tests. Since no food was available, the course of drinking was never interrupted by eating. Theoretically, if a rat faces a simultaneous choice between food and fluid, and if the course of drinking is interrupted by eating, these conditions might interfere with taste preferences, total fluid intake and eating in thirsty rats. The aims of the present experiments were: to ascertain whether food intake during both two-bottle preference and one-bottle acceptance tests in thirsty rats might be influenced by the palatability of the solutions; to verify whether the availability of food during tests influences taste preference and acceptance, and total fluid intake; to detect variations induced by dehydration on body weight and some plasma and urinary parameters that might interfere with food and fluid intake, taste preference and acceptance. Using naive rats, five groups of rats showing the same taste preferences for one of four prototypical tastes and water were selected. Then, both two-bottle preference (Expt 1) and one-bottle acceptance tests (Expt 2) were performed in rats deprived of water for either 12, 24, 36 or 48 h. The results showed that in both Expt 1 and Expt 2, inhibition of feeding and decrease of body weight during dehydration was very similar in all rats. The presence of food during the tests did not affect taste preference and acceptance. During Expt 1, after severe water deprivation (36 and 48 h), food intake was related to the palatability of the solution paired with water. When rats drank either NaCl or sucrose, they ate less food than rats drinking HCl, quinine, or water. In Expt 2, rats drinking NaCl solution as the only source of fluid ate significantly less food than all other groups. The intake of sucrose and/or NaCl solutions be may explained by two different post-ingestion effects (energetic and osmotic). Since rats drinking either sucrose or NaCl ate less food but drank more fluid, they had a significantly higher fluid/food intake ratio than that of rats who drank water, quinine, or HCl, who ate more food but drank less fluid. The increase of the fluid/food intake ratio in rats drinking sucrose or NaCl was directly correlated with the length of dehydration. Self-denial of food during dehydration may be responsible for overeating and overdrinking during the recovery period after tests. After dehydration lasting for 24 and 48 h, plasma [Na(+)], [protein], osmolality and haematocrit values increased but [K(+)] decreased. Urinary volume decreased but urinary [Na(+)] increased. These results are related to food and fluid intake, taste preference and acceptance after dehydration periods. Experimental Physiology (2001) 86.4, 489-498.

[Nutritional status and dietary habits of children in the Province of Modena]. / Stato nutrizionale e abitudini alimentari dei bambini della Provincia di Modena.

Under the auspices of the "Food and health" project, research was undertaken (Nutritional Diagnosis) to evaluate the state of nutrition and health of a sample of the population of the Province of Modena. 155 children of an average age of 10 +/- 2 years were studied. These children, resident in the Local Health Areas 15 (Mirandola), 16 (Modena) and 18 (Pavullo), took part in a questionnaire comprising specific items. A general examination was carried out checking BMI, arterial pressure and pubertal development. Biohumoral examinations were also carried out which, as far as the average haematic lipids were concerned, showed no significant difference between the various Health Areas for CHT, LDL, and TGT, while for HDL there were significant difference (p < 0.01) for Area 16 with respect to Areas 15 and 18. Extremely high values of CHT and LDL were noted in the three areas and low values of HDL, particularly in Area 16. Case histories obtained while completing the questionnaire showed that the children's knowledge of the normality or not of bodily development was fair, since their replies to the question "how is your weight?" had a correlation of r = 0.6 with respective BMI. The prevalence of allergic illness in the three areas is 34.8% with significant differences for some zones and no significant difference for sex. With regard to physical activity, the evidence is disturbing: 31% of the children did not engage in any form of physical recreation whatsoever, which, given the average age of the target group (10 years), is serious. The findings for fatty acids and haematic lipids reflects the findings of an unbalanced diet. It is clear from the findings and observations reported that a study such as this should give rise to primary preventive strategies aimed particularly at young children, to prevent incorrect lifestyles as far as feeding and motor activity are concerned. Bad habits, once established, are difficult to eradicate and lead to obesity and hypercholesterolaemia, sure risk factors for ATS.

Somatostatin administration alters taste preferences in the rat.

The effects of long-term and relatively constant concentrations of somatostatin (SRIF) were tested in rats to investigate its influence on taste preferences, fluid intake, and taste bud topography of the tongue. In SRIF-treated rats, intake of 3 x 10(-2) M NaCl and 6 x 10(-2) M sucrose solution decreased, whereas that of 3 x 10(-5) M quinine-HCl and 10(-3) M HCl (pH = 3) solutions increased significantly; distilled water intake and total fluid consumption remained almost unchanged. The light/dark cycle of consumption of NaCl solution was modified in a dose-dependent manner, but that of dwater, total fluids, and other solutions was not. Histologic exam by light microscopy showed that taste bud distribution on the tongue appeared to be altered, but the results only approached statistical significance. Given that it is possible to remove virtually all taste buds in the oral cavity and have only modest effects on preferences and aversion, it seems very unlikely that the small changes in taste bud distribution are related to the intake of sapid solutions. Since SRIF treatment influenced all sapid stimuli, it seems more likely that the changes are based on a blunted responsiveness in the gustatory system as a whole.

Somatostatin administration modifies food intake, body weight, and gut motility in rat.

The effects of a long period of relatively high and nearly constant levels of Somatostatin (SRIF) on the control of food ingestion and body weight gain were investigated; weight gain occurs via concurrent modifications of food and fluid intake and in vitro gut motility. Fluid intake was not influenced by SRIF treatment. Food intake, body weight, body weight gain, and gut motility decreased after SRIF treatment, and, in some cases, these effects were dose-dependent. Food intake increased significantly during light phase of SRIF treatment. Thus, SRIF treatment produces facilitation of food intake in the light and inhibition in the dark. The suppression seen in the dark may be the result of a preferential activation of the inhibitory response. The increase of food intake during the light may be explained by a decreased availability of body fats as fuels for metabolism since SRIF inhibits GH release, which is involved is the breakdown of adipose tissue into fuels; lower fats synthesis during nocturnal feeding; or both. Decreased gastrointestinal motility also may explain the lower food intake and decreased body weight gain following SRIF treatment.

Simultaneous reversed-phase high-performance liquid chromatographic separation of non-polar isoprenoid lipids and their determination.

A procedure for the rapid identification and determination of non-polar isoprenoid lipids from animal tissues was developed. The complete determination can be carried out by reversed-phase HPLC of just two samples. The first, extracted from unaltered tissues and suitably processed by column chromatography, provides information about free cholesterol, cholesteryl esters, coenzymes Q, free dolichols and dolichyl esters. The second, obtained from saponified tissues, can be used to detect both total cholesterol and total dolichols. Specific calibration graphs were constructed for the determination of the different constituents.

The effect of diet upon the fatty acid composition of cranial and spinal nerve lipids.

The possible basal differences in lipid class and fatty acid composition between a cranial nerve (the trigeminal nerve) and two spinal nerves (the ulnar and sciatic nerves) as well as the effects of dietary lipids on the same nerves were studied. A basal (BD) and four experimental diets containing respectively hydrogenated coconut oil (HCO), grapestone oil (GSO), olive oil (OO) and linseed oil (LSO) were used. Trigeminal lipids fatty acid composition differs significantly from sciatic and ulnar ones in the percentages of 16:0, 16:1, 18:0, 18:2 n-6, 20:0, 20:1, 20:4 n-6, 24:0, 24:1 and 22:6 n-3. Also the proportions of triacylglycerols and free cholesterol strongly differ in trigeminal and spinal nerves whereas no significant difference was detected between ulnar and sciatic nerve lipids. Following the administration of the four experimental diets for 60 days, no significant change was observed in the fatty acid pattern of trigeminal lipids while the spinal ones showed a significant increase in the proportions of the fatty acids present in large quantities in the dietary oils used (i.e.: oleic acid in the OO samples). These changes are probably linked with the rapid metabolic turnover of triacylglycerols, present in larger amounts in spinal nerve lipids.

Dietary-induced changes in lipid and fatty acid composition can modify chronaxie values in the rat sciatic nerve.

The present investigation aimed at clarifying the possible correlations among dietary lipids, peripheral fatty acid composition of nerve lipids and an index of the nervous tissue excitability, the chronaxie. The experiments were performed on female albino rats fed diets containing olive oil (OO) and fish oil (FO) along two generations. Total lipids fatty acid composition of the sciatic nerves from the two groups differed in the proportions of 18:1(n-9), 20:1(n-9), 22-1, 20:5(n-3) and 22:6(n-3). Also the lipid class composition showed significant differences among FO and OO specimens (free cholesterol more concentrated in the OO lipids; triacylglycerols more concentrated in the FO ones). The sciatic nerve isolated from FO rats showed a significant decrease in the chronaxie values if compared to the OO specimens. These results could follow from dietary-induced changes in the perineural permeability and/or possible modifications in the cable properties of the peripheral nerve fibers related to the myelin sheath composition.

Effect of n-6 and n-3 dietary fatty acids on phospholipid composition of plasma, platelets and aorta in the rat.

Female Wistar rats were fed with diets containing as dietary lipids 10% of hydrogenated coconut oil, grape-seed oil, olive oil, linseed oil and fish oil, respectively, for a period of 60 days. At the end of dietary treatment plasma, platelets and aorta phospholipids were extracted and fatty acid spectra determined. Plasma and platelet phospholipids showed the largest diet dependent changes. Anyway in aorta samples too, phospholipids showed marked increase in oleic (olive oil group) linoleic (grape-seed oil group) and alpha linoleic (linseed oil group) acids percentage. Conversely decreased amounts of arachidonic acid were detected in rats fed with diets containing linseed and fish oils. In these samples eicosapentenoic acid partly replaced arachidonic one.

Effect of C 18:3 (n-3) dietary supplementation on the fatty acid composition of the rat brain.

Weanling rats have been fed different diets containing hydrogenated coconut oil or a mixture of grapestone + linseed oil as dietary fats. Groups of 12 animals have been sacrificed at weanling or after 60 or 120 days of this dietary treatment. Body and brain weight, brain total lipids, phospholipids, cholesterol, cerebroside, fatty acid content and fatty acid composition have been evaluated. The diet rich in alphalinolenic acid (C 18:3 n-3) induced a significant increase of the n-3 polyunsaturated fatty acids (C 22:5 and C 22:6, n-3) in the brain, with respect to the other experimental conditions.

Fatty acid composition of single brain structures following different alpha linolenate dietary supplementations.

Weanling female rats randomly divided into three groups were fed a basal alipidic diet added with 10% (w/w) corn oil, soybean oil or linseed oil. After thirty and ninety days of dietary treatment the rats were killed and the fatty acid composition of brain, optic nerve and visual cortex was determined. The results demonstrate a different sensitivity to the diet of the different structures examined and, for the linseed oil treated rats, a strong decrease in the proportions of the total (n-6 + n-3) polyunsaturated fatty acids in all the structures examined.