Amino acid sequences containing cysteine or half-cystine residues in beta-glucuronidase.

Amino acid analysis of oxidized or reduced and carboxymethylated beta-glucuronidase have shown the presence of 24 cysteic acid or S-carboxymethylcysteine residues respectively per mole of the tetrameric enzyme. Titration of sulfhydryl groups gave eight cysteine residues, and by difference 16 half-cystine residues per mole. Six peptides containing radiolabelled cysteine residues were isolated from pepsin and chymotrypsin digest of reduced and S-carboxymethylated beta-glucuronidase by ion-exchange chromatography or gel filtration, followed by paper ionophoresis and paper chromatography.

Amniotic fluid levels of fibrin(ogen) degradation fragment E and alpha-fetoprotein in normal pregnancy and with fetal neural tube defect.

Amniotic fluid levels of alpha-fetoprotein (AFP) and fibrin(ogen) degradation fragment E (FgE) were measured in 214 normal subjects and 27 pregnancies associated with an abnormal fetus (open neural tube defect or exomphalos). AFP levels showed no overlap between the normal and abnormal groups, thus confirming the reliability of the AFP assay in the detection of these abnormalities. FgE levels however showed considerable overlap and could not be used as a diagnostic parameter.

Circulating levels of fibrin/fibrinogen degradation fragment E measured by radioimmunoassay in pre-eclampsia.

Levels of fibrin/fibrinogen degradation products have been measured by a sensitive and specific radioimmunoassay in pregnancies associated with pre-eclampsia or essential hypertension. The incidence of elevated levels was low (2-4%) in mild and moderate cases, and rather higher (30%) in severe cases. In no patients were the levels consistently elevated prior to the onset of clinical signs.

Levels of alpha-fetoprotein in maternal blood as a screening test for fetal neural-tube defect.

A range has been established for maternal plasma-alpha-fetoprotein (A.F.P.

A clinico-pathological study of vulval dermatoses.

A long-term review of 108 women suffering from various forms of vulval dermatosis is described and a detailed analysis of those with chronic hypertrophic vulvitis, lichen sclerosus et atrophicus, and neurodermatitis is made. One case of neurodermatitis and two cases of lichen sclerosus progressed to carcinoma but no case of chronic hypertrophic vulvitis became malignant. It is possible that vulval dermatoses occur more commonly in the nulliparous than in the parous women and there is a slight preponderance of women who are blood group A.

Deoxyribonucleic acid synthesis and cell division in a lon- mutant of Escherichia coli.

The lon(-) mutants of Escherichia coli form long filamentous cells after temporary inhibition of deoxyribonucleic acid (DNA) synthesis by ultraviolet irradiation, treatment with nalidixic acid, or thymine starvation. The kinetics of DNA synthesis and cell division after a period of thymine starvation have been compared in lon(+) and lon(-) cells. After this treatment, both kinds of cells recover their normal DNA to mass ratio with the same kinetics.