Infrared body temperature measurement of mice as an early predictor of death in experimental fungal infections.

Temperatures of mice were measured using an infrared high performance non-contact thermometer, after the device had been calibrated using implantable microchips containing temperature transponders. Mice were infected with three species of Candida (isolates) and the resultant disseminated infections monitored. Mouse temperatures could be reliably measured using the infrared device and this measurement caused little distress to the mice. We were further able to demonstrate that mice rarely recovered if their body temperature dropped below 33.3 degrees C (sensitivity 68%, specificity 97%). Adoption of a 33.3 degrees C endpoint in fungal sepsis experiments measured by infrared non-contact thermometer would significantly reduce the suffering in the terminal stages of this type of infection model.

Optical fiber sensor for electric field and electric charge using low-coherence, Fabry-Perot interferometry.

An optical fiber sensor for electric field and electric charge, based on the deflection of a small cantilever, has been developed. When the sensor head is placed in an electric field, induced charging produces deflection of the cantilever, which is measured using low-coherence, Fabry-Perot interferometry. The sensor has been used to measure the electric field in the vicinity of a Van de Graaff generator, in the range 135-650 V/cm. The measured deflections are in good agreement with the predictions of a simple model equating the electrostatic and mechanical forces acting on the cantilever.

The action of inhibitory neurotransmitters, gamma-aminobutyric acid and glycine may distinguish between the area centralis and the peripheral retina in cats.

The effects of iontophoretically applied gamma-aminobutyric acid (GABA) and glycine, and of their antagonists, bicuculline and strychnine, were compared between ganglion cells from the central and peripheral retinae of optically intact eyes in barbiturate-anaesthetised cats. The visual response of on-cells was inhibited by GABA and enhanced by bicuculline. The visual response of off-cells was inhibited by glycine and enhanced by strychnine. The sensitivity of cells to the transmitters was lower in the peripheral retina than in the area centralis, whilst the sensitivity to the antagonists was similar in both regions of the retina. Cells from the area centralis were inhibited by either GABA or glycine, but never both. Cells from the periphery were less selective and were inhibited by both transmitters.