The study of the antigenic properties of tissues and organs of animals in ontogenesis
SummaryThe antigenic properties of the tissue of developing crystalline lens of ducks was studied with the aid of anaphylactic reaction with desensitization.Morphogenesis, the rate of growth of crystalline lens and content of ribonucleic acid (RNA) in it were investigated simultaneously. It was demonstrated that during the early stages of embryogenesis (90–130 hours) the antigens are present in the tissue of developing crystalline lens, which are specific only for the definite stage of development (stage-specific antigens). There is formation and intensive growth of the primary fibers of the crystalline lens and increased concentration of the RNA during this period.
Detection of Fœtal and Sickle-cell Hæmoglobins in Human Anæmias
WE have systematically examined a large number (175) of normal and anæmic bloods for the presence of fœtal hæmoglobin (F-Hb)1 by three methods: (a) the position of the tryptophan fine-structure band2, using the moving-plate method of Holiday3, from which the relative proportions of adult (A-Hb)1 and fœtal hæmoglobin can be estimated4 when more than 10 per cent of the latter is present, though smaller proportions cannot be detected; (b) the Rich ‘slope’ method5, using the Unicam SP.500 spectrophotometer, which has the same order of sensitivity; (c) the rate of alkaline denaturation at pH 12.8, which provides a sensitive means of detecting the more alkaline-resistant fœtal hæmoglobin6.
Testosterone levels, handedness and sex ratio at birth.
Geschwind has hypothesized that levels of androgens in utero affect postnatal laterality preferences, high levels being associated with left-handedness of offspring. I have hypothesized that high parental androgen levels at the time of conception are associated with subsequent male births. However, left-handed parents seem to produce an excess of female, not male, offspring. This finding could be reconciled with the two hypotheses if individuals who were exposed to high levels of androgens in utero had low circulating levels in adulthood. Some evidence for this loophole is reviewed here. Lyster & Lloyd (1987, J. theor. Biol. 126, 125) have reported that (consistent with the hypotheses) index left-handed men have an excess of brothers; but, contrary to the hypotheses, index left-handed women have an excess of sisters. Accordingly these authors proposed that left-handedness in females is associated not with high levels of androgen in utero, but with a "sensitivity" to it. If such sensitivity were associated with low androgen levels, it might explain an excess of sisters among the sibs of left-handed women. It is shown here that evidence in agreement with this hypothesis (though not discriminating between it and Geschwind's) suggests that the sex ratios of offspring of LH male x RH female and of RH male x LH female matings, are both low.