melatonin suggests that it is well tolerated at the dose used. The present study, however, does not indicate whether it is necessary to take melatonin before and during the flight or only after it. Further research is needed on the dose response characteristics of melatonin to optimise its effect in alleviating jet lag.Overall the results support the use of melatonin for alleviating jet lag and tiredness after long haul flights and indicate further investigations necessary to maximise the positive effects of melatonin.We thank Air New Zealand for its help and support.

Eight histopathologists, based at different hospitals, who had previously examined 100 consecutive colposcopic cervical biopsies were circulated with the results of the initial study. The slides were then 'reblinded' and re-examined by the pathologists who, as before, assigned them into one of six diagnostic categories. The degree of interpathologist agreement for the seven observers who returned usable responses was characterized by kappa statistics and compared to the corresponding figures for the same observers from the previous study. Although some of the observers showed significant alterations in their diagnostic practices there was persistent poor agreement for CIN 1 and 2, mediocre agreement for CIN 3 and excellent agreement for invasive carcinoma. Intra-observer agreement was consistently better than inter-observer agreement for each of the diagnostic categories. Significant differences were found among observers in the degree of intra-observer variability. The 20 cases in which there was most disagreement were re-examined by one of the authors who compared these with 20 biopsies which caused little disagreement. Disagreement was considered to be associated with florid papilloma-virus changes, basal cell hyperplasia and severe inflammation in varying combinations. On the basis of these findings we suggest changes in the terminology of CIN lesions.

No abstract

Two young Jamaican women of Chinese idiopathic thrombocytopenic purpura were found to have lipid-laden histiocytes in their spleens; their condition has improved following splenectomy. The electron microscopic appearances ofspleens suggest that platelet destruction contributed to the accumulation of lipid.

The pyrrolizidine alkaloid, fulvine, is now accepted as a major cause of veno-occlusive disease of the liver in the West Indies, where it is ingested as a decoction of the plant Crotalaria fulva in bush tea. Fulvine is similar in chemical structure to monocrotaline, which is known to cause pulmonary hypertension in rats.Thirty young female rats were given a single dose of fulvine either by intraperitoneal injection (50 mg/kg body weight) or by stomach tube (80 mg/kg body weight). Eleven of these rats died of acute haemorrhagic centrilobular necrosis of the liver, and two of pneumonia, within 23 days of receiving fulvine. These 13 showed no evidence of hypertensive pulmonary vascular disease. The remaining 17 rats (which survived from 24 to 37 days) developed hypertensive pulmonary vascular disease with right ventricular hypertrophy together with medial thickening of the pulmonary trunk and muscular pulmonary arteries. The pulmonary arterioles showed hypertensive changes and some contained thrombi. In four animals an acute necrotizing arteritis also occurred.We have shown that fulvine resembles monocrotaline in its ability to produce pulmonary hypertension in rats. We suggest that, in any patient presenting with unexplained pulmonary hypertension, a careful enquiry should be made to elicit the possibility of recent ingestion of drugs or plant extracts that may have caused a rise in the pulmonary arterial pressure.