Effect of Pre-natal Protein Deprivation on Neonatal Cerebellar Development <Emphasis Type="Italic">in vitro</Emphasis>

MOST biochemical and morphological studies of the effects of nutritional deprivation on the mammalian nervous system have dealt with quantitative undernutrition during the first 21 postnatal days. Findings have included a reduction in brain cellularity^1–4; a delay in neuronal and glial differentiation³; and a decrease in the lipids^3,3–7, lamellae numbers⁸ and stainability^3,5,9 of the myelin sheath. Such studies, even of those regions of the nervous system developing maximally post-natally, may be criticized as enabling the anlage, however undifferentiated, to develop normally until birth. I have, therefore, studied in a tissue culture system the morphogenetic effects of pre-natal maternal protein deprivation on the growth and development of the cerebellum, a region of the brain developing maximally after birth. Cultures of neonatal mouse cerebellum from mothers deprived of protein were analysed in a nutritionally normal environment to determine the effect of pre-natal protein restriction on the post-natal developmental potential of the nervous system.     

EVALUATION OF OLFACTORY INTENSITY: COMPARATIVE STUDY OF TWO METHODS

Two experimental procedures recommended for the evaluation of the psychophysical characteristics of odorous compounds, olfactory matching with the 1-butanol scale and cross-modality matching with the finger span are compared. The intensity of ethyl butyrate and guaiacol solutions presented at four different concentration levels was evaluated by a panel of sixteen subjects over five repetitions using the two methods. Each stimulus was delivered to the subject from a Teflon bag through a nose-shaped glass sniffing port.
The discrimination ability, repeatability, panel homogeneity and within-subject variability of the methods were assessed. Results indicate that with both methods, subjects were able to highly discriminate the presented concentration levels of the odorants. There were no great difference in repeatability and the same individual variability was observed between both methods. However, the smaller within-subject variability highlighted for the 1-butanol scale method suggested that this method is potentially more powerful than finger-span method.