Regulation by transcription factors in bacteria: beyond description.

Transcription is an essential step in gene expression and its understanding has been one of the major interests in molecular and cellular biology. By precisely tuning gene expression, transcriptional regulation determines the molecular machinery for developmental plasticity, homeostasis and adaptation. In this review, we transmit the main ideas or concepts behind regulation by transcription factors and give just enough examples to sustain these main ideas, thus avoiding a classical ennumeration of facts.

Molecular mechanisms involved in the pathogenesis of septic shock.

Pathogenesis of the development of sepsis is highly complex and has been the object of study for many years. The inflammatory phenomena underlying septic shock are described in this review, as well as the enzymes and genes involved in the cellular activation that precedes this condition. The most important molecular aspects are discussed, ranging from the cytokines involved and their respective transduction pathways to the cellular mechanisms related to accelerated catabolism and multi-organic failure.

NF-kappaB dependent activation of human endothelial cells treated with soluble products derived from human lymphomas.

Nuclear factor of the Immunoglobulin Kappa chain of B cells (NF-kappaB) activation is an early event during cytokine-mediated endothelial activation related to increased adhesion of leucocytes. We report that soluble products secreted by two human lymphomas activate NF-kappaB, and increase the ability of endothelial cells to adhere U937 cells in vitro. Analysis of the tumor-derived products revealed the absence of tumor necrosis factor-alpha and interleukin-1beta.