The sweetest pill to swallow: how patient neurobiology can be harnessed to maximise placebo effects.

The burgeoning interest in placebo effects over the last 10-15 years has fallen into two main research areas: elucidation of the neurobiological mechanisms recruited following placebo administration, and investigations into the situations and contexts in which placebo effects are evoked. There has been little attention focused on bridging these two i.e.

Structural comparison of native and deoxycholate-treated purple membrane.

Lipid-depleted purple membrane prepared by extraction with deoxycholate has been compared with the native structure. X-ray and electron diffraction photographs show a reduction in cell dimension from 62.4 to 57.

Arrangement of protofilaments in two forms of tubulin crystal induced by vinblastine.

Tubulin crystals produced by incubation with vinblastine sulphate have been investigated by X-ray diffraction, electron microscopy and density measurement. The results show that crystals produced in vitro from bovine brain tubulin are made of packed helices, each consisting of a single continuous protofilament, whereas crystals produced in vivo in sea urchin eggs are built from pairs of such helices. The symmetry, cell dimensions, percentage protein and composition of the crystals are consistent with either 24 or 30 tubulin monomers per turn of the helix.

Retinal location in purple membrane of Halobacterium halobium: a neutron diffraction study of membranes labelled in vivo with deuterated retinal.

Purple membranes were prepared by growing Halobacterium halobium in a medium containing nicotine (which inhibits biosynthesis of retinal) and the oxidation products of fully deuterated beta-carotene. This allowed the in vivo incorporation of deuterated retinal into the membranes. The labelled membranes were crystalline and isomorphous with native membrane as determined by X-ray diffraction, and their optical absorption spectra were very similar.