To most people's astonishment, the belief (derived from observational studies) that hormone replacement therapy (HRT) offered cardiovascular protection was neatly overturned by the results of randomised clinical trials. Discussing this divergence in Hypertension (2004;44: 789-5), the authors say we shouldn't be walking away from HRT research, as there's still much to be learnt about its effect on the cardiovascular system. For example, are the effects of oestrogen a class effect shared by all oestrogen receptor agonists? What are the effects of oestradiol metabolites on the cardiovascular system? And do progestins affect the metabolism of oestradiol?

Helicobacter pylori is apparently the commonest chronic bacterial infection in humans. In Glasgow, a trawl through the notes of all children who underwent breath testing for H pylori in the children's hospital from 1995 to 2002 identified a highly significant positive association between H pylori colonisation and poverty. Colonisation was most prevalent in the most deprived areas (Scottish Medical Journal 2004;49: 136-8).

Half a million organ donor registration leaflets were recently mailed out to more than 10 000 general practices. Research carried …