Elevated formaldehyde concentration in "Brazilian keratin type" hair-straightening products: a cross-sectional study.

Background: Brazilian keratin treatment (BKT) and similar straightening products fix and retain a straight shape even when the hair is wet. Unacceptably high concentrations of formaldehyde have been reported in such products.

Objective: We sought to measure the formaldehyde concentration in all BKT brands marketed in South Africa in 2012.

Longitudinal changes in CD4(+) T-cell memory responses induced by BCG vaccination of newborns.

Background: Improved vaccination strategies against tuberculosis are needed, such as approaches to boost immunity induced by the current vaccine, BCG. Design of these strategies has been hampered by a lack of knowledge of the kinetics of the human host response induced by neonatal BCG vaccination. Furthermore, the functional and phenotypic attributes of BCG-induced long-lived memory T-cell responses remain unclear.

Kinetic and physical characterisation of recombinant wild-type and mutant human protoporphyrinogen oxidases.

The effects of various protoporphyrinogen oxidase (PPOX) mutations responsible for variegate porphyria (VP), the roles of the arginine-59 residue and the glycines in the conserved flavin binding site, in catalysis and/or cofactor binding, were examined. Wild-type recombinant human PPOX and a selection of mutants were generated, expressed, purified and partially characterised. All mutants had reduced PPOX activity to varying degrees.