Synchrotron x-ray microdiffraction reveals intrinsic structural features of amyloid deposits in situ.

Amyloidoses are increasingly recognized as a major public health concern in Western countries. All amyloidoses share common morphological, structural, and tinctorial properties. These consist of staining by specific dyes, a fibrillar aspect in electron microscopy and a typical cross-β folding in x-ray diffraction patterns.

Surface-isomerization dynamics of trans-stilbene molecules adsorbed on Si(100)-2 x 1.

Photoinduced trans-cis isomerization studies of stilbene molecules in the gas phase have led to a precise understanding of the corresponding molecular dynamics. Yet, when such molecules are adsorbed on surfaces, these reactions are expected to be strongly modified as compared to what is know in the gas phase. In this work, a low temperature (5 K) scanning tunneling microscope (STM) is used to image the trans-stilbene molecules deposited on a Si(100)-2 x 1 surface at 12 K.

Adsorption of HCl on the water ice surface studied by X-ray absorption spectroscopy.

The adsorption state of HCl at 20 and 90 K on crystalline water ice films deposited under ultrahigh vacuum at 150 K has been studied by X-ray absorption spectroscopy at the O1s K-edge and Cl2p L-edge. We show that HCl dissociates at temperatures as low as 20 K, in agreement with the prediction of a spontaneous ionization of HCl on ice. Comparison between the rate of saturation of the "dangling" hydrogen bonds and the chlorine uptake indicates that hydrogen bonding of HCl with the surface native water "dangling" groups only accounts for a small part of the ionization events (20% at 90 K).

Studies of Copper Complexes Displaying N(3)S Coordination as Models for Cu(B) Center of Dopamine beta-Hydroxylase and Peptidylglycine alpha-Hydroxylating Monooxygenase.

We describe the studies of new copper complexes [MeSPY2]CuPF(6), 2, and [MeSPY2]Cu(ClO(4))(2).CH(3)CN, 3, as models for the Cu(B) center of dopamine beta-hydroxylase and peptidylglycine alpha-hydroxylating monooxygenase. The structure of [MeSPY2]Cu(ClO(4))(2).

The human VAV proto-oncogene maps to chromosome region 19p12----19p13.2.

A novel human oncogene, designated VAV, has been recently characterized. This oncogene was generated by a rearrangement within the 5' coding sequences of a normal cellular gene, the VAV proto-oncogene. The normal VAV gene is specifically expressed in hematopoietic cells regardless of their differentiation lineage.