Amyloid-beta42 plasma levels are elevated in amnestic mild cognitive impairment.

Amnestic mild cognitive impairment (aMCI) is considered a prodromal stage of Alzheimer's disease (AD). We measured plasma levels of amyloid-beta40 (Abeta40) and Abeta42 in 191 subjects with aMCI. Seventy-nine of them were clinically followed for two years. In the total cohort of aMCI cases, the average level of Abeta42, as well as the Abeta42/Abeta40 ratio, was significantly higher than those of the 102 cognitively normal age-matched subjects. The aMCI cases that converted to probable AD within 2 years had higher levels of Abeta42 and, to a lesser extent, Abeta40 than the stable cases. However the large variability of measured values indicates that plasma Abeta is not a suitable marker of incipient AD

BDNF Val66Met polymorphism is associated with aggressive behavior in schizophrenia

Brain-derived neurotrophic factor (BDNF) gene variants may potentially influence behaviour. In order to test this hypothesis, we investigated the relationship between BDNF Val66Met polymorphism and aggressive behaviour in a population of schizophrenic patients. Our results showed that increased number of BDNF Met alleles was associated with increased aggressive behaviour

Beam Spin Asymmetry in Semi-Inclusive Electroproduction of Hadron Pairs

International audienceA first measurement of the longitudinal beam spin asymmetry ALU in the semi-inclusive electroproduction of pairs of charged pions is reported. ALU is a higher-twist observable and offers the cleanest access to the nucleon twist-3 parton distribution function e(x). Data have been collected in the Hall-B at Jefferson Lab by impinging a 5.498-GeV electron beam on a liquid-hydrogen target, and reconstructing the scattered electron and the pion pair with the CLAS detector. One-dimensional projections of the ALUsinϕR moments are extracted for the kinematic variables of interest in the valence quark region. The understanding of dihadron production is essential for the interpretation of observables in single-hadron production in semi-inclusive DIS, and pioneering measurements of single-spin asymmetries in dihadron production open a new avenue in studies of QCD dynamics