Deficiencies in anti-acetylcholine receptor antibody measurement in myasthenia gravis.

In a retrospective case note study of 86 patients with myasthenia gravis, 60 had an anti-acetylcholine receptor antibody assay performed by the regional immunology laboratory. Antibody was detected in 38% which compares with 66-93% in other series. Whilst the use of staphylococcal protein A to precipitate the antibody-receptor complex, rather than anti-human immunoglobulin, may be partly responsible for this low sensitivity, other methodological problems are likely to exist.

Depth sense aesthesiometry: an advance in the clinical assessment of sensation in the hands.

Fingertip depth sense threshold has been examined in fifty normal subjects using the simple pocket aesthesiometer invented by Renfrew. Index fingers possessed the lowest thresholds and little fingers the highest, whilst there were no significant differences between the same fingers of either hand. Sex and age (at least up to 70 years) had no significant influence on depth sense threshold, but thickened skin and low intelligence tended to raise thresholds.

Anaesthetics depress the sensitivity of cortical neurones to L-glutamate.

1 The effects of general anaesthetics on the responses of neurones to iontophoretically applied L-glutamate have been examined in slices of the guinea-pig olfactory cortex in vitro. 2 Concentrations of pentobarbitone, ether, methoxyflurance, trichloroethylene and alphaxalone that are known to depress synaptic transmission in the prepiriform cortex also depressed the sensitivity of prepiriform neurones to L-glutamate. 3 Halothane, in concentrations that depress synaptic transmission (less than 1%) did not alter sensitivity of neurones to glutamate.