In vitro effects on calcium oxalate crystallization kinetics and crystal morphology of an aqueous extract from Ceterach officinarum: Analysis of a potential antilithiatic mechanism.

Ceterach officinarum Willd is a plant widespread throughout Europe and used in southern Italy as a diuretic. Beliefs in the benefits of C. officinarum aqueous extract in the treatment of calcium oxalate kidney stones are widely held. Little is known, however, about the actual mechanism of its antilithiatic action. Our results in this in vitro study corroborate C. officinarum aqueous extract as a good source of antioxidants with a high antioxidant effects. Our results also demonstrate a major impact of C. officinarum aqueous extract on in vitro induced calcium oxalate crystallization kinetics and crystal morphology, showing its critical role in kidney stone formation and/or elimination. We show that progressively increasing doses of C. officinarum aqueous extract cause a sequence of effects. A powerful inhibitory action on calcium oxalate monohydrate (COM) growth and aggregation is first observed. C. officinarum aqueous extract also appears highly effective in stimulating nucleation increasing the number and reducing the size of COM crystals, which become progressively thinner, rounded and concave in a dose-dependent manner. These shape-modified COM crystals are known to be less adherent to renal tubular cells and more easily excreted through the urinary tract preventing kidney stone formation. Further, C. officinarum aqueous extract promotes the formation of calcium oxalate dihydrate (COD) rather than the monohydrate so that, at the highest concentrations used, only COD crystals are observed, in significant greater numbers with a clear reduction in their size, in a dose-dependent manner. Furthermore, AFM analyses allowed us to reveal the presence of C. officinarum component(s) on the surfaces of COD and modified COM crystals. The crystal surface adsorbed component(s) are shown to be similarly active as the total aqueous extract, suggesting a trigger factor which may direct crystal modification towards COD forms. In urolithiasis pathogenesis COD crystals are less dangerous than the COM forms due to their lower affinity for renal tubular cells. Our results are important in understanding the mechanisms which guide the modification induced by C. officinarum on the crystallization process. Based on these data, together with no adverse toxic effect being observed on the in vitro model of human intestinal enterocytes, C. officinarum aqueous extract could represent an attractive natural therapy for the treatment of urolithiasis.

Assessment of radioactivity in Italian baby food.

A set of measurements have been conducted to determine the activity-level of natural and artificial radionuclides in some baby foods commercialized in Italy. The measurements have been carried out using liquid scintillation, gamma, alpha and mass spectrometry. The activity concentrations ranged from 0.005 to 0.238, from 0.0082 to 1.65, from 0.0003 to 0.015 and from <13.6 to 233.3 Bq kg-1 for 210Po, 238U, 232Th and 40K respectively, whereas they are below the detection limit for 137Cs and 226Ra. The annual effective dose due to intake of 210Po, 238U, 232Th and 40K ranged from 280 and 800 µSv y-1 for infant 1 year old. These values lie well within the typical worldwide range of dose due to the ingestion of all natural radiation reported by UNSCEAR and they are below the internationally recommended level. This indicates that the baby food available in Italy would not pose any significant radiological impact to infant.

Natural and artificial radioactivity determination of some medicinal plants.

Several medicinal plants used in Italy were analysed to determine natural and artificial radioactivity in those parts (leaves, fruits, seeds, roots, peduncles, flowers, barks, berries, thallus) used generally as remedies. The radionuclides were determined by alpha ((238)U, (210)Po) and gamma ((214)Pb-Bi, (210)Pb, (40)K and (137)Cs) spectrometry. (238)U ranged between <0.1 and 7.32 Bq kg(dry)(-1); (210)Po between <0.1 and 30.3 Bq kg(dry)(-1); (214)Pb-(214)Bi between <0.3 and 16.6 Bq kg(dry)(-1); (210)Pb between <3 and 58.3 Bq kg(dry)(-1); (40)K between 66.2 and 3582.0 Bq kg(dry)(-1); (137)Cs between <0.3 and 10.7 Bq kg(dry)(-1). The percentage of (210)Po extraction in infusion and decoction was also determined; the arithmetical mean value of percentage of (210)Po extraction resulted 20.7+/-7.5.

Natural radioactivity in the mussel Mytilus galloprovincialis derived from the central Adriatic Sea (Italy).

The aim of this study was to determine background levels of natural radionuclides such as uranium isotopes, (210)Pb, (210)Po, and (40)K in mussels Mytilus galloprovincialis, collected in the central Adriatic Sea along the Marche region as a mechanism to establish a biomonitoring model for human radiation exposure resulting from ingestion of this species. This mussel is an invasive warm-water species largely consumed by the local population and also exported to different countries. Among natural radionuclides, alpha emitters are considered responsible for a significant proportion of the radiation exposure of humans to background radiation, particularly through food consumption. The sampling was conducted in different seasons of the year in order to evaluate the spatial and temporal distribution of the natural radioactivity. Data was also compared to previous findings to corroborate our findings. The mean of activity concentration found was 2.34 +/- 0.61 and 149 +/- 58 Bq/kg dry for total uranium and (210)Po, respectively. In mussels the concentration trend of the studied radionuclides was (40)K > (210)Po >> (210)Pb > uranium isotopes. The mean individual dose due to ingestion of mussels for (210)Po was in the range 1.65 yen 10(-2) to 9.20 yen 10(-2) mSv yr(-1). The dose derived from uranium isotopes, (40)K, and (210)Pb was negligible. Data show that mussels may be considered a reliable species model for human biomonitoring for radiation exposure.

Radioactivity measurements and radiation dose evaluation in tap waters of Central Italy.

Consumption of drinking water is very important for human nutrition and its quality must be strictly controlled. A study of radioactivity content in tap water samples collected in the Central Italy was performed in order to check the compliance with recent European regulations. Gross alpha and beta activity, 226Ra, 238U and 234U concentrations were measured. Gross alpha and beta activities were determined by standard ISO 9696 and ISO 9697; for 226Ra determination liquid scintillation was used. 238U and 234U concentrations were determined by alpha spectrometry after separation from matrix by extraction chromatography and electroplating. Recommended WHO guideline activity concentrations for drinking water (0.1 and 1.0 Bq/L for gross alpha and gross beta activity, respectively) are exceeded in two cases for gross alpha activity and are not exceeded in any case for gross beta activity. The concentrations (mBq/L) of 226Ra, 238U and 234U ranged from <1.70 to 15.3, 0.65 to 48.8 and 0.780 to 51.5, respectively. Effective dose due to the uranium isotopes and radium was calculated for children and adults using the dose coefficients reported by EC Directive 96/29 EURATOM and annual water intake. For all class ages, the doses are quite similar and much lower than 0.1 mSv/year.

Chemical and radiochemical characterization of depleted uranium (DU) in Kosovo soils.

As is well known ammunitions containing depleted uranium (DU) were used by NATO during the Balkan war. The paper deals with the determination of uranium alpha emitting radiosotopes in Kosovo soils by chemical separation and alpha spectrometry. The samples were collected by CISAM (Centro Interforze Studi ed Applicazioni Militari, S. Piero a Grado, Livorno) in the period November 1999-April 2000. The DU distribution in soil appeared very disomogeneous; the isotope weight percentages for U-238, U-235 and U-234 resulted 99.76, 0.24 and 7.24.10(-4) respectively; consequently the activity distribution was 86.42%, 1.31%, 11.63% and the isotope ratios were 1.52.10(-2) and 0.134 for U-235/U-238 and U-234/U-238 showing clearly the presence of DU. A small peak at 4.49 MeV (U-236) in the alpha spectrum indicated that the used DU was the by-product of exhausted uranium reprocessing. In order to determine the chemical and physiological solubility of uranium a fractionation study was carried out by using the Tessier method: 55% of uranium showed a fair solubility, but 45% was solubilized only by 8 M HNO3.