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The effects of an arginine-utilizing mycoplasma, Mycoplasma arginini, and of varying levels of arginine in the growth media of the Epstein-Barr virus (EBV)-containing EB1 and EB3 cell lines, and the EBV-free RPMI 1788 cell line, were studied. l-Arginine, at a concentration of 0.1 mM in the growth medium, led to a reduction of the EBV capsid antigen content of the EB1 and EB3 cells lines as determined by indirect immunofluorescence, and M. argininiinfection enhanced this reduction. The synthesis of two immune products, interferon and macrophage migration inhibition factor, was enhanced by growing the cell lines in medium containing arginine at a concentration of 0.1 mM, but the RPMI 1788 cell line produced much less of both products than EB1 or EB3 under these conditions. Infection of the cell lines with M. argininireduced the amount of interferon produced and completely inhibited macrophage migration inhibition factor synthesis. The addition of arginine to a final concentration of 0.6 mM in the growth medium caused a dual effect: the EB1 and EB3 cell lines maintained the original level of EBV capsid antigens, even when infected with M. arginini;immune product synthesis was greatly reduced or completely inhibited by the addition of arginine, and M. argininiinfection caused no further reduction of immune product synthesis.

A 36-year-old woman had the rare combination of congenital hemihypertrophy and ipsilateral congenital indifference to pain. This appears to be the first description of a patient with congenital hemihypertrophy in whom diffuse neurological deficits were found on the involved side.

In order to assess the quantitative significance of the de novocholesterol synthesis in the foeto-placental unit at midgestation, two midgestation foetuses and two complete foeto-placental units were perfused with [14C]-sodium acetate immediately following their removal at laparotomy. The perfusions were carried out at 36°C for 120 min administering 3.0 and 6.0 mCi of [14C] sodium acetate, respectively. The amount of [14C]-cholesterol formed was estimated on the basis of the recovery of [7α-3H]-cholesterol internal standard present in the radiochemically homogeneous cholesterol isolated from the various tissues.The cholesterol isolated from the placentas was devoid of any [14C] label. On the other hand, [14C] cholesterol was isolated from all perfusates, as well as from all foetal tissues studied, including the adrenals, livers, testicles, brains and residual foetal tissues.The average quantity of radiochemically homogeneous [14C] cholesterol formed by the four foetuses corresponded to 0.68% of the radioactive material perfused: 0.45% was isolated from the liver, 0.13% from the adrenals, 0.01% from the testicles and 0.08% from the perfusates.Cholesterol sulphate was also isolated from the extracts of adrenals, livers and perfusates. The quantity of [14C] cholesterol sulphate formed was much less than that of [14C] cholesterol; following correction for procedural losses, the total amount of [14C] cholesterol sulphate isolated did not exceed 0.01% of the perfused material.It is concluded that the midgestation human foetus synthesizes large quantities of cholesterol, utilizing small molecular material such as sodium acetate as a precursor and that part of the cholesterol synthesized by the foetus is secreted to the placenta.

The following steroids, [7α-3H]5-androstene-3β,16α,17β-triol and [4-14C] 5-androstene-3β,16β,17β-triol were biosynthesized and their metabolism was studied in two subjects at midgestation, following placental perfusion in situ.Among the metabolites isolated in a radiochemically homogeneous form, exclusively 3H-labelled 16α,17β-dihydroxy-4-androsten-3-one was isolated from the extracts of placentas and perfusates. Exclusively 14C-labelled 16β,17β-dihydroxy-4-androsten-3-one was isolated from the placentas and perfusates and 16-epioestriol (1,3,5(10)-oestratriene-3,16β,17β-triol) from the placentas, perfusates and urine specimens. The following compounds contained both 3H and 14C-label: oestriol (placentas and urine specimens) and 5β-androstane-3α,16α,17β-triol (urine specimens).The 3H/14C-ratio of oestriol isolated from the urine specimens was much lower than that of urinary 5β-androstane-3α,16α,17β-triol, or that of the oestriol isolated from the placentas. The 3H/14C-ratio of the oestriol isolated from the urine 2–4 days following the perfusion was lower than that of the perfused material.It is concluded that a considerable amount of the 16-epioestriol secreted by the placenta is gradually converted to oestriol by the maternal organism. A limited conversion occurs also in the placenta.

Two complete foeto-placental units were perfused at midgestation with 5.0 mCi of uniformly labelled 14C-sodium acetate plus 5.0 mCi of cholesterol-7α-3H and two isolated foetuses were perfused with 2.5 mCi of 14C-labelled sodium acetate plus 2.5 mCi of cholesterol-7α-3H. The perfusions were carried out at 35–36°C for 90 min. The foetal adrenals, livers, testes and perfusates were analyzed and various labelled steroids were isolated in a radiochemically homogeneous form.Major quantities of 14C- and 3H-labelled pregnenolone (3β-hydroxy-pregn-5-en-20-one) and dehydroepiandrosterone (3β-hydroxy-androst-5-en-17-one) were isolated from the foetal perfusates, livers and adrenals. Minor amounts of 14C- and 3H-labelled progesterone (pregn-4-ene-3,20-dione) were isolated from the perfusates and adrenals, and 17α-hydroxy-progesterone (17α-hydroxy-pregn-4-ene-3,20-dione) and androstenedione (androst-4-ene-3,17-dione) from the perfusates. Smaller amounts of exclusively 14C-labelled androstenedione were isolated also from the adrenals. No labelled progesterone, androstenedione or testosterone (17β-hydroxy-androst-4-en-3-one) was detected in the testes. Attempts to isolate 20α-dihydroprogesterone (20α-hydroxy-pregn-4-en-3-one) or 20β-dihydroprogesterone (20β-hydroxy-pregn-4-en-3-one) from the perfusates, adrenals and livers failed. No labelled cortisol (11β,17,21-trihydroxy-pregn-4-ene-3,20-dione) or corticosterone (11β,21-dihydroxy-pregn-4-ene-3,20-dione) was detected in the adrenals, and no testosterone, oestrone (3-hydroxy-oestra-1,3,5(10)-trien-17-one) or 16α-hydroxy-dehydroepiandrosterone (3β,16α-dihydroxy-androst-5-en-17-one) in the perfusates.Pregnenolone and dehydroepiandrosterone (which were present in approximately equal amounts) accounted for as much as 95% of all steroids isolated from all sources. The bulk of these two steroids was isolated from the perfusates. The 14C/3H ratio of the pregnenolone and dehydroepiandrosterone isolated from the conjugated fraction of the perfusates was much higher than that of the unconjugated compounds.It is concluded that the midgestation human foetus is capable per seof carrying out the de novosynthesis of major quantities of pregnenolone and dehydroepiandrosterone. It is suggested that in foetal steroidogenesis acetate is utilized predominantly viaa conjugated pathway and circulating cholesterol mainly viaan unconjugated pathway.

The quantitative significance of the de novosynthesis of Δ5- and Δ4-steroids was assessed in the midgestation human foetus. Two midgestation foetuses and two complete foeto-placental units were perfused at 36°C for 120 minutes with 3.0 and 6.0 mCi of [14C] sodium acetate, respectively, and radiochemically homogeneous carbon-14 labelled steroids were isolated from the adrenals, livers and perfusates. Losses throughout the isolation procedure were monitored in all tissues of all experiments by the recovery of tritium labelled internal standards.In the four experiments, a total of 18.0 mCi of [14C] sodium acetate was perfused and a total of 0.17 μCi of pregnenolone, 2.65 μCi of pregnenolone sulphate, 1.07 μCi of dehydroepiandrosterone and 8.64 μCi of dehydroepiandrosterone sulphate were isolated. A total of 12.53 μCi were isolated in the form of these four compounds; 10.13 μCi of this was present in the perfusates. In all, 0.07% of the administered [14C]-sodium acetate was converted to the four Δ5-steroids studied and 0.048% to dehydroepiandrosterone sulphate.Progesterone was isolated from the perfusates and liver extracts, and 17α-hydroxy-progesterone, androstenedione and testosterone from the perfusates. In the four experiments, a total of 0.045 μCi of carbon-14 labelled Δ4-steroids were isolated, predominantly from the perfusates. In all, less than 0.0003% of the perfused [14C] sodium acetate was converted to Δ4-steroids. Thus, almost 300 times more Δ5- than Δ4-steroids were formed.It is concluded that the extensive de novosteroidogenetic processes taking place in the midgestation human foetus lead to the predominant formation of Δ5-steroid sulphates.