Showing papers by "Nuffield Orthopaedic Centre published in 1970"

Biosynthesis of Monoterpenes in Rose Flowers

Abstract: ALTHOUGH mevalonic acid (MVA) is generally assumed to be an obligatory precursor of terpenes in higher plants, incorporation of 2-14C-MVA into the principal monoterpenes of numerous species is almost invariably less than 1 per cent (ref. 1). Monoterpene biosynthesis is nevertheless assumed to occur via conversion of MVA into isopentenyl pyrophosphate (IPP) and 3,3-dimethyl-allylpyrophosphate (DMAPP) which condense to form, directly or in sequence, geranyl or neryl pyrophosphates (GPP and NPP), the presumed precursors of straight chain and cyclic monoterpenes respectively. More than 80 per cent of the total label from 2-14C-MVA, however, has been found to pass into that part of several thujane derivatives2, camphor3, pulegone4 and artemisia ketone4, and of certain sesquiterpenes5 also, which was derived from IPP. In only one example6 has a monoterpene, other than a methyl cyclopentanoid monoterpene, biosynthesized from 2-14C-MVA by a higher plant been shown to contain radioactivity comparably distributed between the moieties derived from IPP and DMAPP. All these experiments involved feeding leaf and stem tissue for 1–5 days, and less than 0.1 per cent of the applied tracer was incorporated during this period.

Thiemann's disease. Osteochondrosis juvenilis of the basal epiphyses of the phalanges of the hand. Report of two cases.

Abstract: Two brothers with osteochondrosis of the phalangeal epiphyses in the hand (Thiemann's disease) are described and the condition discussed.

The survival of cells in human bone after exposure to air and saline correlated with deoxyribonucleic acid abnormalities.

Abstract: Adult human cancellous bone was used to determine the viability of bone cells after timed exposure to air and saline. To determine the viability of the bone cells, the Feulgen reaction was used in conjunction with tissue culture. It is concluded that no osteocytes survived after 30 minutes exposure to air or saline. Marrow cells do not survive after 2 hours exposure to air, or 6 hours exposure to saline. The number of surviving cells after exposure to air or saline progressively diminishes as the time of exposure increases.