PURPOSE Reported breast cancer incidence is rising in South Africa, where some women are diagnosed late and have poor outcomes. We studied patient and provider factors associated with clinical stage at diagnosis among women diagnosed at the Chris Hani Baragwanath Academic Hospital in Soweto, Johannesburg in 2015-2016. METHODS From face-to-face interviewer-administered questionnaires we compar...

BACKGROUND Chronic low-grade inflammation is recognized as an important factor contributing to senescence and age-related diseases. In mammals, levels of polyamines (PAs) decrease during the ageing process; PAs are known to decrease systemic inflammation by inhibiting inflammatory cytokine synthesis in macrophages. Reductions in intestinal luminal PAs levels have been associated with intestinal...

We have examined the cation requirements of rabbit liver tRNA nucleotidyltransferase. The enzyme had an absolute requirement fo a divalent cation which could be satisfied by Mg2+, Mn2+ or Co2+. In contrast to the Escherichia coli enzyme, we have found no evidence to implicate Zn2+ in the action of rabbit liver tRNA nucleotidyltransferase. We have also identified a second cation requirement whic...

We have shown previously that depletion of polyamines delays apoptosis induced by camptothecin in rat intestinal epithelial cells (IEC-6). Mitochondria play an important role in the regulation of apoptosis in mammalian cells because apoptotic signals induce mitochondria to release cytochrome c. The latter interacts with Apaf-1 to activate caspase-9, which in turn activates downstream caspase-3....

Forbes, M. (Lederle Laboratories Division, Pearl River, N.Y.), N. A. Kuck, and E. A. Peets. Effect of ethambutol on nucleic acid metabolism in Mycobacterium smegmatis and its reversal by polyamines and divalent cations. J. Bacteriol. 89:1299-1305. 1965.-Mycobacterium smegmatis, harvested from cultures inhibited by ethambutol and then suspended in drug-free medium, exhibited a prolonged lag befo...

Polyamines are important endogenous regulators of ion channels and are known to modulate inflammation and nociception. Here we investigated effects of polyamines on the capsaicin receptor TRPV1, a major ion channel expressed in nociceptive sensory afferents. Extracellular spermine, spermidine, and putrescine directly activated TRPV1 in a charge-dependent manner, both in heterologous expression ...

Four different molecular dynamics (MD) simulations have been performed for ordered DNA decamers, d(5'-ATGCAGTCAG)*d(5'-TGACTGCATC). The counterions were the two natural polyamines spermidine3+ (Spd3+) and putrescine2+ (Put2+), the synthetic polyamine diaminopropane2+ (DAP2+) and Na+. The simulation set-up corresponds to an infinite array of parallel DNA mimicking the state in oriented DNA fiber...

The mechanism of yeast ornithine decarboxylase (ODC) regulation in response to polyamines was examined. ODC catalyzes the first step of polyamine biosynthesis, the conversion of ornithine to putrescine. ODC activity was modulated approximately 200-fold by varying the availability of polyamines. Variations in ODC activity were associated with parallel changes in the amount of active enzyme molec...

The polyamines are abundant biogenic cations implicated in many biological processes. Despite a plethora of evidence on polyamine-induced DNA conformational changes, no thorough study of their effects on the activities of sequence-specific DNA binding proteins has been performed. We describe the in vitro effects of polyamines on the activities of purified, representative DNA-binding proteins, a...

Plants are challenged by a variety of biotic or abiotic stresses, which can affect their growth and development, productivity, and geographic distribution. In order to survive adverse environmental conditions, plants have evolved various adaptive strategies, among which is the accumulation of metabolites that play protective roles. A well-established example of the metabolites that are involved...