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H Read

Publications and source records attributed to H Read.

12 recordsLinked to original sources

Which factors are responsible for the changing lichen floras of London?

SO(2) is no longer the principal factor influencing the vitality and composition of lichen assemblages in London. We provide direct evidence for an impact on lichen growth during episodic high exhaust emissions coupled with unusual climatic conditions. This suggests a combination of particles and nitrogen plays a major role in influencing lichen growth. Nitrogen from traffic emissions may be at least as important as agriculture in influencing the composition of lichen assemblages.

Agriculture↗

Protein-bound cobalamin absorption declines in the elderly.

A modified protein-bound cobalamin absorption test was used to study dietary cobalamin absorption in healthy adults of different age groups and patients with isolated low serum concentrations of cobalamin. Dietary cobalamin absorption was significantly reduced in healthy adults aged 55-75 years compared with young adults, with a further reduction in those older than 75 years. No difference was detected between dietary cobalamin absorption in patients with isolated low serum cobalamin and controls of a similar age group. Cobalamin malabsorption was associated with elevated serum gastrin. The diagnostic value of this protein-bound cobalamin absorption test in the elderly was limited by the frequent finding of reduced absorption in healthy elderly people with normal serum cobalamin concentrations. The performance of such tests should be evaluated in different age groups before application in diagnosis.

Adult↗

Prophylaxis of cyanobacterial and mushroom cyclic peptide toxins.

The pathogenicity of virulent cyclic peptide toxins of the cyanobacterium, Microcystis aeruginosa, and the mushroom, Amanita phalloides, was prevented in mice by pretreatment with a variety of chemically unrelated agents including hydrocortisone, shellac, certain diazo and triazine dyes and cyclosporine. A. Despite the diverse nature of the protective agents, a feature commonly associated with protection was the ability to impair hepatic uptake of 51Cr-labeled sheep erythrocytes, a function of hepatic macrophages (Kupffer cells). In addition, several of the protective agents are known to affect other aspects of reticuloendothelial cell function. Therefore it seems likely that the hepatic macrophage is involved in the observed protection, although by what mechanism(s) is unknown. The most remarkable prophylaxis was seen with a single injection of Trypan red, which provided nonimmunologic protection against a lethal dose of a cyanobacterial toxin, cyanoginosin-LR, for periods up to 3 months.

Amanitins↗