An x-ray nebula associated with the millisecond pulsar B1957+20.

We have detected an x-ray nebula around the binary millisecond pulsar B1957+20. A narrow tail, corresponding to the shocked pulsar wind, is seen interior to the known Halpha bow shock and proves the long-held assumption that the rotational energy of millisecond pulsars is dissipated through relativistic winds. Unresolved x-ray emission likely represents the shock where the winds of the pulsar and its companion collide. This emission indicates that the efficiency with which relativistic particles are accelerated in the postshock flow is similar to that for young pulsars, despite the shock proximity and much weaker surface magnetic field of this millisecond pulsar.

A reexamination of the composition of diets associated with pellagra.

Diets described in historical studies of human pellagra, have been reexamined by using modern tables of nutrient composition. Five apparently pellagragenic diets from field studies were estimated to have niacin equivalents (NE) well in excess of the Recommended Dietary Allowance (RDA), i.e., 6.6 mg/1000 kcal. In these diets, the estimated contribution of riboflavin was below the RDA, i.e., 0.6 mg/1000 kcal. A series of trials of the pellagra-preventive value of different foods carried out by the U.S. Public Health Service from 1920 to 1936 used over 400 women subjects, of whom fifty developed signs of pellagra on diets now calculated to contribute 7.2-10.6 mg NE/1000 kcal. Most of these diets apparently had less than 60% of the RDA for riboflavin. Further calculations, assuming that the niacin in ordinary cereal foods has only 30% bioavailability, still left half of the pellagragenic diets apparently with more than the RDA for "available NE." Possible reasons for the apparent discrepancy between these results and the RDA's calculated from more recent controlled studies are discussed. It is suggested that the pellagra epidemic in the U.S.A. in the early 1900's has not yet been explained satisfactorily.

A randomized study of misonidazole and radiotherapy for grade 3 and 4 cerebral astrocytoma.

The results are reported of a small clinical trial carried out to assess the potential value of the hypoxic cell radiosensitizer misonidazole in the radiation treatment of Grade 3 and 4 supratentorial astrocytomas. A total of 55 patients were randomly allocated to one of 3 treatment groups. No significant differences were seen between the median survivals of patients in the 2 control radiation groups and that of the third group in which oral misonidazole at a dose of 3 g/m2 preceded each of 4 weekly radiation doses. Possible reasons why no improvement was seen are discussed in detail.

Long-term outcome after severe head injury.

From a consecutive series of 7000 patients with head injuries admitted to the regional accident service, Radcliffe Infirmary, Oxford between 10 and 24 years earlier, every patient was taken who had been amnesic or unconscious for one week or longer. Of these 479 patients, all but ten were traced, and either the cause of death was established or the survivors examined. Ten years after injury 4% were totally disabled, and 14% severely disabled to a degree precluding normal occupational or social life. Of the remainder, 49% had recovered, and the rest were dead. Additionally, a selected series of 64 patients whose unconsciousness had been prolonged for a month or more were studied. Forty of these had survived between three and 25 years after injury and were re-examined. On the basis of age at injury, the worst state of neurological responsiveness, and the duration of posttraumatic amnesia, the outcome of head injury can be predicted reliably in most cases. Patients and relatives need more reassurance and simple psychotherapeutic support, especially in the first few months after injury. Extrapolation from our figures suggests that each year in England and Wales 210 patients survive totally disabled and another 1500 are severely disabled.

Predictive factors in open myelomeningocele with special reference to sensory level.

A total of 113 cases of open myelomeningocele operated on shortly after birth were followed up and the 80 survivors (71%) were assessed one and a quarter to seven and a half years later. Their disability was classified in terms of mobility, intelligence, continence, and major complications; these when combined provided an assessment of overall disability. The overall disability of the survivors was minimal in 6%, moderate in 40%, severe in 39%, and very severe in 15%.A number of clinical features present at birth were analysed for their predictive value. Of these the sensory level, which frequently differed from both external and radiological levels of the lesion, correlated with the outcome in terms of mobility, intelligence, continence, major complications, and overall disability; and also with deaths caused by renal failure.A policy of confining operation to those patients with a reasonable chance of achieving independence would involve selecting for treatment a minority of all infants born with open myelomeningocele.