When mammalian spermatozoa are washed free from seminal plasma (and thus from fructose) and incubated as suspensions in Ringer solution they remain motile provided that oxygen is present. An explanation of this behaviour was put forward by Lardy & Phillips (1941a, b), who suggested that in the absence of the seminal sugar [later identified by Mann (1946) as fructose] the spermatozoa of bull and...

Rat liver phenylalanine hydroxylase can be markedly activated by a variety of different procedures including those that lead to covalent modification of the enzyme, such as limited proteolysis by alpha-chymotrypsin and alkylation of sulfhydryl groups by N-ethylmaleimide, and those that lead to reversible changes, such as the interaction of the enzyme with lysolecithin and related compounds. The...

The family of sphingosine-1-phosphate receptors (S1PRs) is G-protein-coupled, comprised of subtypes S1PR1-S1PR5 and activated by the endogenous ligand S1P. The phosphorylated version of Fingolimod (pFTY720), an oral therapy for multiple sclerosis (MS), induces S1PR1 internalisation in T cells, subsequent insensitivity to S1P gradients and sequestering of these cells within lymphoid organs, thus...