Palladium uptake by Pisum sativum: partitioning and effects on growth and reproduction.

Environmental palladium levels are increasing because of anthropogenic activities. The considerable mobility of the metal, due to solubilisation phenomena, and its known bioavailability may indicate interactions with higher organisms. The aim of the study was to determine the Pd uptake and distribution in the various organs of the higher plant Pisum sativum and the metal-induced effects on its growth and reproduction. P. sativum was grown in vermiculite with a modified Hoagland's solution of nutrients in the presence of Pd at concentrations ranging 0.10-25 mg/L. After 8-10 weeks in a controlled environment room, plants were harvested and dissected to isolate the roots, stems, leaves, pods and peas. The samples were analysed for Pd content using AAS and SEM-EDX. P. sativum absorbed Pd, supplied as K2PdCl4, beginning at seed germination and continuing throughout its life. Minimal doses (0.10-1.0 mg Pd/L) severely inhibited pea reproductive processes while showing a peculiar hormetic effect on root development. Pd concentrations ≥1 mg/L induced developmental delay, with late growth resumption, increased leaf biomass (up to 25%) and a 15-20% reduction of root mass. Unsuccessful repeated blossoming efforts led to misshapen pods and no seed production. Photosynthesis was also disrupted. The absorbed Pd (ca. 0.5 % of the supplied metal) was primarily fixed in the root, specifically in the cortex, reaching concentrations up to 200 µg/g. The metal moved through the stem (up to 1 µg/g) to the leaves (2 µg/g) and pods (0.3 µg/g). The presence of Pd in the pea fruits, together with established evidence of environmental Pd accumulation and bioavailability, suggests possible contamination of food plants and propagation in the food chain and must be the cause for concern.

Fatty acid content of serum lipid fractions and blood lipids in normolipidaemic volunteers fed two types of cheese having different fat compositions: a pilot study.

The aim of this randomised, double-blind, crossover study in normolipidaemic volunteers was to investigate the effect of consumption of an experimental cheese (from cows fed a grass and maize silage-based diet with 5% of linseed oil added) or a control cheese (without linseed oil) on both plasma lipids and fatty acid content of serum lipid fractions. A lower content of medium-chain saturated fatty acids as well as a higher content of stearic acid and polyunsaturated fatty acids were found in the experimental cheese; its consumption was successful in limiting the enhanced blood concentration of atherogenic fatty acids, without affecting fatty acid content of serum lipid fractions. These results indicate that dairy products could be considered as key foods for fat modifications with the objective of optimizing their nutritional quality.

Synthesis, reactivity, electrochemical behavior, and crystal structure of a family of multivalent metal carbido-carbonyl clusters based on the Rh10(C)2Au(4-6) framework.

Six metal carbido-carbonyl clusters have been isolated and recognized as members of a multivalent family based on the dioctahedral Rh(10)(C)(2) frame, with variable numbers of CO ligands, AuPPh(3) moieties, and anionic charge: [Rh(10)(C)(2)(CO)(x)(AuPPh(3))(y)](n-) (x = 18, 20; y = 4, 5, 6; n = 0, 1, 2). Anions [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(4)](-) ([2](-)) and [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(4)](2-) ([2](2-)) have been obtained by the reduction of [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(4)] (2) under N(2), while [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(5)](-) ([3](-)) was obtained from [Rh(10)(C)(2)(CO)(20)(AuPPh(3))(4)] (1) by reduction under a CO atmosphere. [3](-) can be better obtained by the addition of AuPPh(3)Cl to [2](2-). [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(6)] (4) is obtained from [3](-) and 2 as well by the reduction and subsequent addition of AuPPh(3)Cl. The molecular structures of [2](2-) ([NBu(4)](+) salt), [3](-) ([NMe(4)](+) salt), and 4 have been determined by single-crystal X-ray diffraction. The redox activities of complexes 1, 2 and [3](-) have been investigated by electrochemical and electron paramagnetic resonance (EPR) techniques. The data from EPR spectroscopy have been accounted for by theoretical calculations.

Mediterranean Diet Effect: an Italian picture.

BACKGROUND: The purpose of this study was to evaluate the overall diet quality effects, mainly on antioxidant nutritional status and some cytokines related to the cellular immune response as well as oxidative stress in a healthy Italian population group. METHODS: An observational study was conducted on 131 healthy free-living subjects. Dietary intake was assessed by dietary diary. Standardised procedures were used to make anthropometric measurements. On blood samples (serum, plasma and whole blood) were evaluated: antioxidant status by vitamin A, vitamin E, carotenoids, vitamin C, uric acid, SH groups, SOD and GPx activities; lipid blood profile by total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides; total antioxidant capacity by FRAP and TRAP; the immune status by TNF-α, and IL-10 cytokines; the levels of malondialdehyde in the erythrocytes as marker of lipid peroxidation. RESULTS: The daily macronutrients intake (g/day) have shown a high lipids consumption and significant differences between the sexes with regard to daily micronutrients intake. On total sample mean Mediterranean Diet Score (MDS) was 4.5 ± 1.6 and no significant differences between the sexes were present. A greater adherence to a Mediterranean dietary pattern increases the circulating plasma levels of carotenoids (lutein plus zeaxanthin, cryptoxanthin, α and ß-carotene), vitamin A and vitamin E. The levels of endogenous antioxidants were also improved. We observed higher levels in anti-inflammatory effect cytokines (IL-10) in subjects with MDS ≥ 6, by contrast, subjects with MDS ≤ 3 show higher levels in sense of proinflammatory (TNF α P < 0.05). Lower levels of MDA were associated with MDS > 4. Our data suggest a protective role of vitamin A against chronic inflammatory conditions especially in subjects with the highest adherence to the Mediterranean-type dietary pattern. CONCLUSIONS: Mediterranean dietary pattern is associated with significant amelioration of multiple risk factors, including a better cardiovascular risk profile, reduced oxidative stress and modulation of inflammation.

Differential effect of cheese fatty acid composition on blood lipid profile and redox status in normolipidemic volunteers: a pilot study.

The present study investigated the effect of the consumption of two cheese varieties differing for fat quality on blood lipid profile and redox status biomarkers in 30 selected healthy volunteers, consuming either the experimental cheese (from milk produced by cows fed a grass and maize silage based diet with 5% of linseed oil added) or the control cheese (from normal cows' milk) for 4 weeks according to a crossover design. The experimental cheese had a lower content of medium-chain saturated fatty acids and a higher content of stearic acid and polyunsaturated fatty acids; its consumption led to higher levels of vitamins C and E and stearic acid in blood, while myristic acid and oxidized low-density lipoprotein concentrations were significantly lower. As myristic acid and oxidized low-density lipoprotein are highly correlated with increased atherogenic risk and vitamins C and E with antioxidant activity, the enrichment of cows' diet with linseed oil could provide a dietary option to prevent cardiovascular diseases risk.

Physiological and molecular effects associated with palladium treatment in Pseudokirchneriella subcapitata.

Human activities have increased the levels of environmental palladium (Pd) worldwide. Due to the growing evidence of its toxicity, Pd pollution has become the focus of serious concern. Several studies have given an account of the increasing concentration of Pd in aquatic ecosystems. The aim of the current study is to analyze the physiological and molecular effects induced by Pd on freshwater unicellular green algae. To do this, Pseudokirchneriella subcapitata (P. subcapitata) was exposed in vitro to different concentrations (0.1, 0.25 and 0.5 mg l(-1)) of K(2)PdCl(4), a soluble salt of Pd, corresponding to 0.03, 0.075 and 0.15 mg l(-1) of Pd. The uptake and the effects on algal growth and morphology were determined. The main results are that Pd is able to induce damage in P. subcapitata at a concentration of 0.1 mg l(-1) of K(2)PdCl(4), with the damage becoming more evident at a concentration of 0.25 mg l(-1)of K(2)PdCl(4); at a concentration of 0.5 mg l(-1) of K(2)PdCl(4), cellular degeneration occurs. The main cellular target of Pd is the chloroplast, as shown by TEM and proteomic analysis. TEM analysis also showed accumulation of precipitates, probably of Pd, in the chloroplasts, although further experiments are necessary to confirm that these are Pd-precipitates. Amplified fragment length polymorphism analysis (AFLP) demonstrated that Pd, even at the lowest concentration tested, induced randomly distributed DNA changes either directly or indirectly in the algal genome and that oxidative processes were involved.

Bioavailability of strawberry antioxidants in human subjects.

Strawberries contain many antioxidant phytochemicals such as vitamin C, carotenoids and phenolic compounds including anthocyanins (ACN). In the present study, antioxidant composition of fresh strawberries (FS) and stored strawberries (SS) and the bioavailability of the main strawberry bioactive compounds were determined in human subjects. Thirteen healthy volunteers consumed 300 g of FS and SS on two separate occasions. Blood, before and at different time points from meal consumption, as well as 24 h urine, was collected, and parent compounds and metabolites of the different compounds were determined by HPLC or LC/MS/MS. A reduction in α-carotene plasma concentrations v. baseline values was recorded after the consumption of FS, although the amount of this carotenoid was higher in the SS. On the contrary, a significant increase of plasma vitamin C after 2, 3 and 5 h (P < 0.05) of FS and SS consumption was recorded. No quercetin and ACN were found in plasma, while coumaric acid, 4-hydroxybenzoic acid (4HBA, 56 and 54% of pelargonidin-3-glucoside (Pel-glc) ingested with FS and SS, respectively) and protocatechuic acid (59 and 34% of cyanidin-3-glucoside ingested with FS and SS, respectively) over 8 h from strawberry consumption were retrieved in the plasma. Pelargonidin glucuronide, pelargonidin glucoside and pelargonidin aglycone peaked in urine within 2 h of strawberry consumption, and the 24 h amount excreted was always approximately 0.9% of the Pel-glc dose ingested. The data indicated that the content of phytochemicals in strawberries may influence the bioavailability of individual compounds. Furthermore, in the present study, the metabolism of Pel-glc was elucidated, and, for the first time, 4HBA was suggested to be a major human metabolite of Pel-glc.

Platinum, palladium, and rhodium deposition to the Prunus laurus cerasus leaf surface as an indicator of the vehicular traffic pollution in the city of Varese area: an easy and reliable method to detect PGEs released from automobile catalytic converters.

BACKGROUND, AIM, AND SCOPE: The widespread use of some platinum group elements as catalysts to minimize emission of pollutants from combustion engines produced a constantly growing increase of the concentration of these elements in the environment; their potential toxicological properties explain the increasing interest in routine easy monitoring. We have found that leaves of Prunus laurus cerasus are efficient collectors of particulate with a dimension <60-80 mum, and a simple and reliable procedure was developed to reveal traces of platinum, palladium, and rhodium released from automotive catalysts. The analysis of the dust deposited on the foliage is a direct indicator of traffic pollution. MATERIALS AND METHODS: Leaves of P. laurus cerasus were washed by sonication in a mixture of water and 2-propanol and the washings, to be discarded, were separated by centrifugation to yield typically 0.05-1.2 g of dust that, after mineralization, was directly submitted for atomic absorption analysis. RESULTS: Comparison of the 2007 and 2004-2005 results showed a dramatic reduction of the platinum levels and revealed that palladium is now the main component of this traffic-related pollution. DISCUSSION: The results are consistent with the increasing diffusion of cars with a diesel engine whose catalysts are made up of Pt and/or Pd alone, and gives a significant insight into the recent evolution in catalyst design that replaces platinum for palladium. CONCLUSIONS: The proposed analytical procedure is simple, with short preparation times, and greatly reduces matrix effects so that atomic absorption spectroscopy can easily detect the three noble metals at the ng/g level in the dust. RECOMMENDATION AND PERSPECTIVES: The results clearly show that Pd concentrations have increased over time, and must be cause for concern.

Mixed Co-Rh nitrido-encapsulated carbonyl clusters. synthesis, solid-state structure, and electrochemical/EPR characterization of the anions [Co10Rh(N)2(CO)21]3-, [Co10Rh2(N)2(CO)24]2-, and [Co11Rh(N)2(CO)24]2-.

The nitrido-encapsulated heterometallic cluster anions [Co(10)Rh(N)2(CO)21](3-) (1), [Co(10)Rh2(N)2(CO)24](2-) (2), and [Co(11)Rh(N)2(CO)24](2-) (3) have been obtained by tailored redox-condensation reactions. These three anions are rare high-nuclearity mixed-metal clusters containing two interstitial nitrogen atoms. Their structures have been determined by single-crystal X-ray diffraction on their [NR4]+ salts (R = Me for 1 and 3, R = Et for 2), and their electrochemical and ESR properties have been studied in detail. It is noteworthy that 1 has an unprecedented stereochemistry that does not exhibit a close geometrical resemblance with the isoelectronic homometallic anion [Co(11)N2(CO)11(mu2-CO)10](3-), and 2, despite its even number of electrons, is a paramagnetic species.

Water security in Uzbekistan: implication of return waters on the Amu Darya water quality.

GOAL, SCOPE AND BACKGROUND: Amu Darya river, one of the main water resources of Uzbekistan, shows a relevant longitudinal enrichment of soluble contents which strongly limits the human uses of its waters. Because of the low natural run-off processes, salts and pollutants are mainly driven to the river by the return waters used for washing and irrigating the surrounding lands. The influence of return waters on stream quality is dramatically relevant in the lower reaches of the river where almost all the flowing waters have been previously used for the agriculture practises. To provide analytical evidence on the potential effects of return waters on the quality of the Amu Darya river, the paper reports and comments data on salinity and metals contents of the waters flowing in the artificial channel network of Bukhara and in the Amu Darya river, from Bukhara up to the dam forming the Tuyamuyn Hydro Complex (THC). METHODS: A total of 15 sampling sites were selected for the analytical survey: Two sites were located on the Amu Darya river downstream from the inflow of the return waters from Bukhara, two in the river entering in the THC, and three downstream from the dam forming the reservoir complex. The waters entering and leaving the Bukhara agricultural area were sampled in two main collectors, while the waters flowing in the channel system were sampled in six distinct collectors. The following parameters were considered in the survey: pH, Oxygen, Hardness, Salinity, Conductivity, P-PO4(3-), P tot, N tot, N-NO3(2-), N-NO2-, COD, Ca2+, Mg2+, Fe, Mn, Zn, Cr, Cu, Ni, Cd, Pb. RESULTS AND DISCUSSION: Salt concentrations below 1000 mg/l were measured in the Amu Darya waters upstream to Bukhara. In the drainage system, salinity exceeds the palatability limit and reaches the maximum peak of 3200 mg/l in the outflow collector. Due to dilution effects, salinity returns to lower values (400-700 mg/l) along the Amu Darya river downstream from Bukhara; calcium and magnesium resulted the major constituents of the overall salinity. No serious metal contaminations were detected in the waters entering and leaving the examined channel system. Differently, the Amu Darya waters upstream to the THC showed a relevant metal contamination, with Cr, Ni, Fe concentrations exceeding the limits for human consumption. In the downstream sites, located in the Tuyamuyn Hydro Complex and in the Amu Darya river flowing out from this reservoir, excluding Fe, all the examined metals showed lover concentrations and values below the normative limits. CONCLUSION: The direct human consumption of the lower Amu Darya waters is strongly limited by salinity and by metal contamination. Although the salinity of the return waters from the Bukhara drainage system results in above normal limits, no corresponding increases were measured in the Amu Darya river downstream from the return water inflow at the time of the survey. As for the metal contamination of the Amu Darya river, the survey revealed the presence of relevant sources of metal contamination downstream from Bukhara external to the agricultural drainage system. This contamination resulted in reduced sedimentation processes taking place in the limnetic zones of the Amu Darya river upstream to the dam forming the Tuyamuyn Hydro Complex. RECOMMENDATION AND OUTLOOK: To fully understand the longitudinal increase of Amu Darya salinity, an evaluation of the cumulative effects of the loads from the main agricultural areas is required, also by using mass-balance models. As for the metals, an investigation should be addressed to identify the anthropogenic sources of contaminations present in the lower Amu Darya region and the metal loads should be diverted.

Electron transfer and CO addition to polynitrido cobalt carbonyl clusters: parallel pathways for conversion of the [Co10N2(CO)19]4- anion to the novel [Co11N2(CO)21]3- anion.

The redox aptitude of the dinitrido anion [Co10N2(CO)19]4- has been tested from both chemical and electrochemical points of view, together with its reactivity toward CO that induces disproportionation. In any case, through a remarkable overlapping of intermediate steps, the new anion [Co11N2(CO)21]3- (4) is eventually obtained. A detailed study of the pathways to 4 allowed the identification of three labile intermediates by their characteristic IR spectra as well as their electrochemical and paramagnetic properties. The unprecedented structure of trianion 4 has been studied in details in two different crystalline salts.

Synthesis and structural characterization of the [[Rh(5)(CO)(14)]-(H(2)N(CH(2))(4)NH(2))-[Rh(5)(CO)(14)])](2-) and [Rh(5)(CO)(13)(H(2)N(CH(2))(2)NH(2))](-) anions (as [PPh(4)](+) salts): an unprecedented example of carbonyl substitution by alkylamines in a homoleptic metal carbonyl cluster anion.

The substitution of one or two carbonyls by many different primary and secondary alkylamines and -diamines has been established for the first time in a homoleptic carbonyl cluster anion, the trigonal bipyramidal [Rh(5)(CO)(15)](-). Two derivatives, the bis-monosubstituted [[Rh(5)(CO)(14)]-(H(2)N(CH(2))(4)NH(2))-[Rh(5)(CO)(14)]](2-) dianion (1) and the disubstituted chelated [Rh(5)(CO)(13)(H(2)N(CH(2))(2)NH(2))](-) monoanion (2), have been structurally characterized, both in the solid state (as [PPh(4)](+) salts) and in solution, revealing that the sites of the substitution are the cluster apexes. (13)C NMR spectra of 2 revealed localized fluxionality of the CO ligands over the temperature range 298-183 K.

Mixed Ruthenium-Rhodium Carbonyl Cluster Complexes. Synthesis of the Anions [Ru(3)Rh(CO)(13)](-) and [RuRh(3)(CO)(12)](-) and Crystal Structures of Their [N(PPh(3))(2)](+) Salts(1).

The new anion [Ru(3)Rh(CO)(13)](-) (1) has been obtained by reaction of [Rh(CO)(4)](-) ([N(PPh(3))(2)](+) or [PPh(4)](+) salt) with Ru(3)(CO)(12); [RuRh(3)(CO)(12)](-) (2) has been derived by oxidative degradation of [RuRh(4)(CO)(12)](2-). Their salts, [N(PPh(3))(2)][Ru(3)Rh(CO)(13)] (I) and [N(PPh(3))(2)][RuRh(3)(CO)(12)] (II), were characterized by single-crystal X-ray diffraction. Data for I: space group P&onemacr;, a = 9.827(2) Å, b =14.911(2) Å, c = 18.735(3) Å, alpha = 110.53(1) degrees, beta = 99.79(2) degrees, gamma = 91.85(2) degrees, R1 = 0.0342, wR2 = 0.0926 for 7257 independent reflections with I > 3sigma(I). Data for II: space group P2(1)/c, a = 14.746(3) Å, b = 21.395(4) Å, c = 16.140(4) Å, beta = 102.95(2) degrees, R1 = 0.0582, wR2 = 0.1383 for 4381 independent reflections with I > 3sigma(I). Both anions have a tetrahedral metal frame; 1 has an idealized C(3) symmetry, with the Rh atom and its unique terminal carbonyl on the 3-fold axis; nine more carbonyls are terminally bonded to the three Ru atoms, while three bridge the Ru-Rh edges. In 2, which has an idealized C(s)() symmetry, three carbonyls are terminally bound on the Ru atom, and one, one, and two CO, respectively, on Rh1, Rh2, and Rh3; five more CO bridge all edges but the Ru-Rh3 edge. It is worthy of note that subtle details of the CO ligands stereochemistry allowed the correct labeling of metal centers, otherwise indistinguishable on the basis of good quality X-ray diffraction data only. Compound 1 reacts with PPh(3), yielding the rhodium-substituted [Ru(3)Rh(CO)(12)(PPh(3))](-) (1a) ((31)P NMR; 56.9 ppm (d), J(P-)(Rh) = 188 Hz). (13)C NMR spectrum of 1 is a doublet (207 ppm, J(C-Rh) = 17.5 Hz) consistently with a fluxional behavior with complete CO scrambling, from 295 down to 170 K.