202,685 research outputs found
Rapporto sulle nuove misure di CO2 nella galleria drenante Pavone di Vena (06 Settembre 2006)
No full textL’intervento è stato effettuato su segnalazione fatta il giorno 30 Agosto 2006 dal
Geometra Alletto a S. Giammanco. Secondo quanto riferito dal Geom. Alletto, a partire da
quella mattina si stava verificando un forte accumulo di gas all’interno della galleria
drenante Pavone ubicata in Contrada Rocca Campana di Vena, tanto da impedirne
l’accesso al personale operaio ivi presente quotidianamente. Tale fenomeno risultava
simile a quello segnalato nel Novembre 2005, a seguito del quale si era effettuato un
precedente intervento (vedasi rapporto interno UFVG2005/115).Istituto Nazionale di Geofisica e VulcanologiaUnpublishedope
Rapporto sulle nuove misure di CO2 nella galleria drenante Pavone di Vena (06 Settembre 2006)
No full textL’intervento è stato effettuato su segnalazione fatta il giorno 30 Agosto 2006 dal
Geometra Alletto a S. Giammanco. Secondo quanto riferito dal Geom. Alletto, a partire da
quella mattina si stava verificando un forte accumulo di gas all’interno della galleria
drenante Pavone ubicata in Contrada Rocca Campana di Vena, tanto da impedirne
l’accesso al personale operaio ivi presente quotidianamente. Tale fenomeno risultava
simile a quello segnalato nel Novembre 2005, a seguito del quale si era effettuato un
precedente intervento (vedasi rapporto interno UFVG2005/115).Istituto Nazionale di Geofisica e VulcanologiaUnpublishedope
Emissioni di radon dal suolo a Torre del Filosofo (Etna): aggiornamento dati alla ripresa dell’attività stromboliana del Cratere di Sud-Est (30-31 Agosto 2006)
No full textIl 12 Luglio 2005 è stata installata una sonda tipo “barasol” in località Torre del Filosofo (~2920 m sul
mare, alto fianco meridionale del vulcano Etna), finalizzata al monitoraggio in continuo del gas Radon (vedi rapporto
UFVG/074). Tali studi ricadono nell’ambito della Convenzione che l’INGV ha stipulato con il Dipartimento della Protezione
Civile (progetto V3_6/28 – Etna, coordinatori S. Gresta e P. Papale, resp. M. Neri), la cui prima fase è iniziata il 1° giugno
2005. In questa nota descriviamo i risultati ottenuti contemporaneamente alla ripresa dell’attività stromboliana al Cratere di
Sud-Est (vedi aggiornamenti sul sito http://www.ct.ingv.it/Etna2006/Main.htm).Istituto Nazionale di Geofisica e VulcanologiaUnpublishedope
Selenium a cure for autoimmune thyroiditis?
No full textAutoimmune thyroiditis (AT) is a disease whose incidence has increased dramatically over the past few decades. In iodine
sufficient areas, this pathological condition affects up to 5% of the general population. The higher incidence of AT observed
in areas of the world with low-selenium (Se) soils apperas to be the consequence of a reduced activity of the intracellular Sedependent
glutathione peroxidase activity. Se is involved, through selenoproteins, in the regulation of intracellular
antioxidant, redox and anti-inflammatory processes. As a component of selenoproteins, Se exerts various structural and
enzymatic functions. A low Se/high fat diet can cause selenoprotein changes and promote the expression of proinflammatory
factors. In particular, it has been well recognized as an antioxidant and trace element catalyst essential in the
production of thyroid hormone. Selenium is important for the functioning of the immune system. The recommended daily
dose for adults of 55 μ
[Molecular methods in the epidemiology of gram-negative bacterial infections]
No full textIdentification and typing of bacterial isolates from patients and environment are necessary in order to detect the sources of infections. In recent years different molecular typing methods have been carried out and proved more reliable than methods based on phenotypical characters. We have applied two methods of genotyping, i. e. ribotyping and rrnARDRA (Amplified Ribosomal DNA Restriction Analysis) methods, to the study of different bacterial species. Ribotyping was the first universal method for molecular typing of bacteria. We have succeded both in typing various species of enterobacteria (Salmonella Wien, S. Enteritidis, Shigella sonnei, Proteus spp., Morganella morganii, Providencia spp.) by using different restriction endonucleases and in demonstrating the epidemiological importance of the ribotypes identified in each species. Genotyping by rrnARDRA is an identification method based on the analysis of the electrophoretic patterns obtained after restriction endonucleases digestion of the rrn operon sequences amplified by polymerase chain reaction. This is a universal method, because both the same primers and the same endonucleases are utilized for the identification of Gram-positive as well as Gram-negative bacteria. The identification of a bacterial isolate is performed by comparing its profile (number of bands and molecular weight of the fragments) with those from a data-base of profiles of the various species
THE ANTIOXIDANT PROPERTIES OF PHENOLIC MOLECULES IN RELATIONSHIP WITH THE pH OF ENVIRONMENT REACTION
No full textTHE ANTIOXIDANT PROPERTIES OF PHENOLIC MOLECULES IN RELATIONSHIP WITH THE pH OF ENVIRONMENT REACTION
Some epidemiological evidence suggests beneficial effects on human health from a diet rich in fruit, vegetables and certain types of beverages such as tea and wine (1,2). These compounds do not have nutritive properties but they have a functional role in the human organism. Some studies have investigated the effect of pH on the antioxidant properties of polyphenols (3,4) and have reported that the pH-dependent behaviour is related to hydroxyl deprotonation. However, these studies did not compare the antioxidant activity of various classes of polyphenols and did not take into account the acidic pH. The aim of this study was toevaluate either the antioxidant or pro- oxidant behaviors of various polyphenol compounds by the crocin bleaching assay (5-7) in order to investigate the influence of two different pH levels. Thirteen polyphenols were analysed. They were used at 1 mmol/L in a phosphate buffer (pH7.4) and in synthetic wine (pH3.5). The myricetin, quercetin and kaempferol were prepared at concentrations of 0.5mmol/L in both pH, because with an increasing concentration of these compounds, a decreased sensitivity of the method was observed .The behavior of these molecules were analysed at pH 3.5 to simulate the food source; on the other hand, the same compounds were evaluated in a reaction mixture at pH 7.4 to simulate the in vivo condition. The position and the total number of hydroxyl and methoxy groups influence the magnitude and mechanism of the antioxidant activity. The flavonols and flavan-3-ols reveal differences in antioxidant property only at physiological pH, whereas for phenolic acids, both pH 3.5 and 7.4 determine a diversification in antioxidant potential in relationship to their chemical structure. The cinnamic acids are more active than the respective benzoic acids at both pH levels. Data produced indicate that the antioxidant properties of polyphenol compounds are strongly influenced by pH level. The polyphenolic compounds are more sensitive to pH change than to the number and position of substitution groups.
Reference
1 Lotito, S.B., Frei, B., 2006, Free Radical Biology & Medicine ,41, 1727–46.
2Fernandez-Pachon ́, M.S.,Villaño,D.,Garcıa-Parrilla, M.C.,Troncoso, A.M., 2004. Analıtica Chimica Acta 513, 113–8.
3Tyrakowska, B., Soffers, A. E. M. F., Szymusiak, H., Boeren, S., Boersma, M.G., Lemanska, K., Zielinski, R., Vervoort, J., Rietjens, I.M.C.M., 1999, Free Radical Biology & Medicine 27, 1427– 36
4 Lemanska, K., Szymusiak, H., Tyrakowska, B., Zielinski, R., Soffers, A.E.M.F., Rietjens, I.M.C.M., 2001, Free Radical Biology &Medicine 31, 869–81.
5Tubaro F, Micossi E,Ursini F. Journal American Oil Chemical Society 1996, 73, 173–9
6Ordoudi, S. A., & Tsimidou, M. Z. 2006, Journal of Agricultural Food Chemistry, 54, 1663–71.
7Di Majo D,La Guardia M,Giammanco S,La Neve L,Giammanco M. Food Chemistry 2008,111,45-
ANALYSIS OF TOTAL ANTIOXIDANT CAPACITY AND TOTAL PHENOLIC CONTENT (TP) DURING RIPENING OF TWO SICILIAN RED GRAPES VARIETIES
No full textANALYSIS OF TOTAL ANTIOXIDANT CAPACITY AND TOTAL PHENOLIC CONTENT (TP) DURING RIPENING OF TWO SICILIAN RED GRAPES VARIETIES
During the last decade the interest for polyphenols has increased considerably because numerous epidemiological studies, supported by several short term controlled randomised clinical trials, have suggested associations between consumption of polyphenol-rich food or beverages and the prevention of certain chronic diseases associated with the oxidative stress condition (1). In a our previous study on several samples of Sicilian red wine we found that the total polyphenol parameter can not to characterize the nutraceutical properties of a wine by only because the correlation between antioxidant capacity and the total phenolic contents is weak (2). Grapes composition influences the quality of wine and the polyphenolic compounds are an index to establish the exact time of grapes harvest. During the ripening grapes the polyphenolic content changes and this aspect modify the chemical, technological and nutritional characteristics of a wine. The aim of work was to determine the Total Antioxidant Capacity (TAC) by crocin bleaching assay (2-4) and Total Phenolic Content (TP) by Folin Ciocalteau method of two Sicilian red grapes varieties, Nero d’Avola and Petit Verdot, during ripening for three consecutive vintages. In order to valorize the healthy qualities of grapes and to establish whether exist a period during ripening in which the best technologic, nutraceutical and salutistic parameters coexist.
In all vintages, statistically significant differences in TP values were found between the three varieties (p<0.01), In all three years Nero d’Avola grape musts have shown the higher TP values than Petit Verdot. Moreover, during 2008 and 2009 ripening, TP values increased, respectively, of 23.1% and 7.3% for Nero d’Avola, and 30.9% and 55.7% for Petit Verdot. All TP variations proved to be associated with climatic conditions. The antioxidant characteristics of different cultivars are unequally influenced by the vintages. In 2009, Petit Verdot has shown the best antioxidant properties while Nero d’Avola during the 2010 vintage. Significant positive correlations between TP and TAC were detected during the 2009 vintage only: indeed, Nero d’Avola grapes reached their TP and TAC peak values after 13 days from the beginning of ripening, while Petit Verdot grapes after 26 days. Determination of TP during grape ripening is critical to assess the best period of grape harvest. However, higher TP values do not always overlap with higher TAC values, which are indeed strictly related to nutraceutical properties.
Reference
1Rodrigo R, Miranda A,Vergara L, Clinica Chimica Acta 2011, 412, 410-24
2Di Majo D,La Guardia M,Giammanco S,La Neve L,Giammanco M. Food Chemistry 2008,111,45-9
3Tubaro F, Micossi E,Ursini F. Journal American Oil Chemical Society 1996, 73, 173–9
4Ordoudi, S. A., & Tsimidou, M. Z. 2006, Journal of Agricultural Food Chemistry, 54, 1663–71
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