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Many epidemiological studies have shown the beneficial effects of a largely plant-based diet, and the strong association between the consumption of a Mediterranean-type diet with healthy aging including a lower risk of cognitive decline. The Mediterranean diet is characterized by a high intake of olive oil, fruits and vegetables and is rich in dietary fiber and polyphenols – both of which have been postulated to act as important mediators of these benefits. Polyphenols are large molecules produced by plants to protect them from environmental threats and injury. When ingested by humans, as little as 5% of these molecules are absorbed in the small intestine with the majority metabolized by the gut microbiota into absorbable simple phenolic compounds. Flavan-3-ols, a type of flavonoid, contained in grapes, berries, pome fruits, tea, and cocoa have been associated with many beneficial effects on several risk factors for cardiovascular disease, cognitive function and brain regions involved in memory formation. Both preclinical and clinical studies suggest that these brain and heart benefits can be attributed to endothelial vascular effects and anti-inflammatory properties among others. More recently the gut microbiota has emerged as a potential modulator of the aging brain and intriguingly polyphenols have been shown to alter microbiota composition and be metabolized by different microbial species. However, there is a need for well controlled studies in large populations to identify predictors of response, particularly given the vast inter-individual variation of human gut microbiota. [ABSTRACT FROM AUTHOR]

Background and objectives: A cross-sectional observation suggests that total antioxidant capacity (TAC) of the diet positively affects plasma concentrations of [beta]-carotene independent of [beta]-carotene intake. This study was carried out to investigate the effect of two dietary strategies, designed to be comparable in fruits, vegetables, fibre, alcohol and [beta]-carotene intake but substantially different in their TAC, on changes in antioxidant intake and antioxidant status, and in particular in circulating [beta]-carotene concentrations. Subjects: A randomized cross-over intervention trial involving 33 healthy participants and consisting of two 14-day dietary periods (high TAC diet, HT; low TAC diet, LT) with a 14-day washout in between was conducted. Results: Energy, macronutrient, dietary fibre, alcohol and [beta]-carotene intake was not significantly different between LT and HT, whereas intake of other carotenoids and dietary TAC was significantly higher in the HT than in the LT (P Conclusions: The increase in circulating [beta]-carotene along with the increase in dietary TAC suggests that plasma [beta]-carotene could be a marker of TAC intake rather than of [beta]-carotene intake itself. This may explain, in part, why [beta]-carotene supplementation alone has shown no benefit in chronic disease prevention and adds to a putative beneficial role of high dietary TAC diets, which merits further investigation. doi:10.1038/ejcn.2009.46; published online 17 June 2009 Keywords: diet; antioxidants; total antioxidant capacity; [beta]-carotene; intervention study, Introduction Epidemiological evidence supports the strategy of increasing plant food consumption by the general population as a tool for primary prevention against cardiovascular diseases (Gillman et al., 1995; Rimm et [...]

On a global scale, the Crotone basin preserves one of the best-developed and most complete Pleistocene marine records available in outcrop, as important as those in California, New Zealand, and Japan. A deformed, markedly cyclothemic, lower to middle Pleistocene succession is present in the territory of San Mauro Marchesato (Crotone area, southern Italy), showing an overall shallowing trend from slope mudstones to marginal marine and continental deposits. Preservation and high resolution of cyclothems occurred through the interaction between high-amplitude relative sea-level fluctuations, a particular pattern of differential subsidence due to intrabasinal tectonics, and high rates of sediment supply. The studied succession was laid down in the Crotone basin under an extensional tectonic regime, following a major, middle Pliocene contractional phase probably of transpressional nature. Two major unconformities, locally accompanied by angular discordances, occur within the succession. The former, centered at ca. 1.2 Ma, is thought to reflect the opening of the San Mauro subbasin within the Crotone basin in the early Pleistocene, following dextral transtensional motion along north- to north-northeast--trending faults. The latter, with a hiatus lasting from ca. 0.65 to 0.45 Ma, may reflect the decoupling of the Calabrian block with respect to Adria and Sicily, allowing further advancing of the Calabrian are in the Ionian area, where subduction could continue until the present time. The lower part of the succession (the H. sellii and 'large Gephyrocapsa' Zones, from ca. 1.67 to ca. 1.23 Ma) consists of slope to outer-shelf monotonous mudstones and is bounded at the top by the first unconformity, whose gap suppresses the upper part of to locally the entire 'large Gephyrocapsa' Zone (1.608-1.235 Ma) and the lower part of the 'small Gephyrocapsa' Zone (1.235-0.96 Ma). A number of cyclothems developed in an outer- to inner-shelf environment within the 'small Gephyrocapsa' Zone. Biomagnetostratigraphic constraints strongly support a correlation between the condensed sections of cyclothems and MIS (marine isotope stage) 33 to MIS 25. From the base of the P. lacunosa Zone (at ca. 0.96 Ma) upward, the succession rapidly becomes sand dominated, a change that can be confidently correlated with the major climatic shift associated with MIS 24 to MIS 22. In the following succession, two tephra layers, named 'Pitagora ash' and 'Parmenide ash,' provide mappable isochronous surfaces across the subbasin. The sedimentary record is remarkably cyclothemic, characterized by a stack of simple or composite, seaward-prograding, sand-dominated tongues and intervening aggradational deposits related to transgressive-deepening episodes. The cyclothems can be confidently correlated with the oxygen isotope record up to the Matuyama-Brunhes inversion, i.e., up to MIS 19, whereas the stratigraphic record postdating MIS 19 has poorer chronological constraints. Dating is provided by tracing the Parmenide ash in the deeper-water coeval succession of the southern part of the Crotone basin, where the deposits including the ash can be correlated by means of nannofossil biostratigraphy with termination V (transition from MIS 12 to MIS 11). The second unconformity marks an abrupt increase in the proximal character of the sedimentary deposits forming the cyclothems, which incorporate increasing amounts of marginal-marine to continental deposits in the upper part of the subbasin infill. Several lines of direct and indirect evidence indicate that, in spite of the dramatic role of tectonics in shaping stratigraphic architecture, the roles of tectonics and eustasy can be disentangled, owing to the different time scales of the tectonic events and the high-frequency, high-amplitude glacioeustatic Pleistocene cycles. Interaction between intrabasinal tectonics and high rates of sediment supply allowed forced regressive and possibly also lowstand systems tracts to be preserved in some cyclothems, particularly in the lower part of the succession, an unusual fact in shelf deposits. Considering the far younger age of marine terraces on the Ionian side of Calabria when compared to the Tyrrhenian side, it is thought that, during ongoing subduction of the Ionian crust, a wave of uplift and related extensional tectonics migrated southeastward in the rear of the frontal accretionary wedge. Keywords: Pleistocene, cyclothems, basin analysis, neotectonics, eustasy, chronology.

The synthesis of palladium metallacycles from corresponding chloroalkylcomplexes or cyclooctadiene and bases or by ligand exchange reactions is described. The palladacycles, belonging to group 10 metallacycles, react with activated akynes and sulfur dioxide forming insertion products.