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The deacidification of high-acidity oils from Black cumin seeds (Nigella sativa) was investigated with supercritical carbon dioxide at two temperatures (40 and 60°C), pressures (15 and 20 MPa) and polarities (pure CO2 and CO2/10% MeOH). For pure CO2 at a relatively low pressure (15 MPa) and relatively high temperature (60°C), the deacidification of a highacidity (37.7 wt% free fatty acid) oil to a low-acidity (7.8 wt% free fatty acid) oil was achieved. The free fatty acids were quantitatively (90 wt%) extracted from the oil and left the majority (77 wt%) of the valuable neutral oils in the seed to be recovered at a later stage by using a higher extraction pressure. By reducing the extraction temperature to 40°C, increasing the extraction pressure to 20 MPa, or increasing the polarity of the supercritical fluid via the addition of a methanol modifier, the selectivity of the extraction was significantly reduced; the amount of neutral oil that co-extracted with the free fatty acids was increased from 23 to 94 wt%.

he ontogeny of cells containing the enzyme terminal deoxynucleotidyl transferase (TdT) in human fetal liver, bone marrow, and thymus has been studied using a highly specific antiserum to TdT together with monoclonal antiprecursor cell antibodies in double and triple marker immunofluorescence. TdT+ cells were first observed in fetal liver at 12 wk of gestation and accounted for 55% of the lymphoid-like cells isolated after Ficoll-Hypaque separation. TdT+ cells were first observed in the bone marrow 16 wk after gestation. Like TdT+ cells in normal infant bone marrow, the majority of TdT+ cells in fetal liver and bone marrow expressed both BA-1 and RFB-1 antigens. This suggests that fetal TdT+ cells include progenitors of the B lineage (BA-1+) and perhaps of thymocytes (RFB-1+). Nevertheless, TdT was not observed in fetal thymocytes until after 20 wk of gestation, although thymic blasts and the majority of thymocytes were strongly RFB-1+ from 12 wk of gestation. These results clearly show that fetal thymus is first populated by TdT, RFB-1+, BA-1 cells, but does not exclude the fact that a second “wave” of TdT+ prothymocytes, possibly bone marrow derived, also exists.

1. Evidence for the occurrence of a rapidly polymerizing equilibrium system in freshly prepared aqueous solutions of porcine neurophysin has been obtained by frontal and zonal analysis of gel-filtration elution patterns. 2. Elution volumes increased with decreasing protein concentration and derivative analysis of fronts suggested the existence of different polymerizing forms varying in relative proportion with protein concentration. 3. In the presence of lysine vasopressin, the results suggested a shift of the equilibrium in favour of higher polymerizing forms. 4. In the presence of Ca2+ elution patterns became characteristic of a monodisperse system of relatively high molecular weight. The effect of Ca2+ did not survive removal of the ion and was not reproduced by Mg2+. 5. Evidence for a slowly developing polymerization of neurophysin in aqueous solution has been obtained in experiments with solution prepared 24 hr before subjection to gel-filtration. 6. A model is proposed for the description of the binding of lysine vasopressin to porcine neurophysin.

1. The concentration of Bromophenol Blue used as tracking dye in polyacrylamide-gel electrophoresis affected the resolution of rat neurophysins. 2. A final dye concentration of 1μg/ml in the tris–glycine running buffer was found to give the best results. 3. The presence of two major and one minor neurophysin(s) in the rat was confirmed. 4. The two major proteins were found to re-run as single discrete bands, which had the same mobilities in the absence of dye and different mobilities in its presence.

Substances that have not exhibited properties as excitants of ectopic activity by intracoronary injection into normal hearts often produce rapid ectopic activity and sometimes ventricular fibrillation upon slow injection through the vascular bed of an infarcted area, particularly upon the first one or two injections. Sodium lactate has reduced and stopped ectopic activity for brief periods. Excesses of both potassium and calcium have increased ectopic activity in infarction and produced it in normal hearts. No antagonism between these two ions, with respect to ectopic activity, has been demonstrated.

The change in the radioactivity of vasopressin–neurophysin in the rat neurohypophysis after an intracisternal injection of [35S]cysteine was fitted to several mathematical models. The data fitted best a model in which there is a linear input of radioactive protein into one pool of the neurohypophysis, from which it is either released by an exponential process or transferred to a second pool from which it is released by a second exponential process with a rate constant much lower than the first. This model is compatible with the existence of a ‘readily releasable’ pool first postulated by Sachs et al. (1967). Data for the change in radioactivity of vasopressin also gave a good fit in this model. Calculation of the rate constants suggested that the first pool represented about 2% of the total hormone.

1. Rat neurohypophysial extracts have been examined by polyacrylamide-gel electrophoresis. 2. Three of the proteins were tentatively identified as neurophysins by their acidic nature and their disappearance after dehydration of the animals. 3. These proteins were radioactive 24h after intracisternal injection of [35S]cysteine. 4. Two of the proteins were present in much greater quantities than the third, and these two were present in the gland in the same ratio as the hormones vasopressin and oxytocin. 5. One of these proteins was absent from glands of rats homozygous for diabetes insipidus but present in heterozygous animals. 6. It is suggested that these two proteins are the vasopressin–neurophysin and oxytocin–neurophysin of the rat.