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Tumor necrosis factor-alpha (TNF-α) is a pro-inflammatory cytokine produced by a variety of cells, including hematopoietic and non-hematopoietic cells, malignant cells, macrophages, B lymphocytes, T lymphocytes, natural killer cells, neutrophils, astrocytes, endothelial cells, and smooth muscle cells. TNF-α is a homo-trimeric molecular whose individual subunits are composed of antiparallel beta-sheets, forming a regular triangular prism shape. TNF-α binds to three receptor molecules through its receptor-binding sites, which are at the base of its pyramid structure. Biological responses to TNF-α are mediated through two different receptors: TNFR1 and TNFR2. These receptors are transmembrane glycoproteins with extracellular domains containing multiple cysteine-rich repeats that are structurally and functionally homologous, and the intracellular domains that are discrete and transduce their signals through both overlapping and distinct pathways. However, though TNF-α was initially discovered as an anti-tumor agent, it has been revealed that TNF-α and other ligands of this family are involved in some diseases like cancer, neurological, pulmonary, cardiovascular and autoimmune diseases and metabolic disorders. In general, TNF-α activates the control systems involved in cell proliferation, differentiation, inflammation and cell death, and the regulation of immune system. Although a normal level of TNF-α is very important for the regulation of immune responses, the persistence of the immune response as a result of inappropriate and excessive production of TNF-α can cause some inflammatory or autoimmune diseases. Accordingly, either neutralization TNF-α or blockade of its receptors using TNF-α inhibitors can be an effective therapeutic strategy to prevent or treat such inflammatory diseases. Several methods have been used to inhibit TNF-α, including the production of chimeric or fully human antibodies, soluble TNF-α receptors, or anti-TNF-α small molecules. The two previous agents are mostly capable of inhibiting the binding of TNF-α to its associated receptors, while anti-TNF-α small molecules, in addition to the above, inhibit the biosynthesis of TNF-α by blocking TNF-α mRNA biosynthesis, through the inhibition of its post-translational processing, or by blocking TNF-α receptors. Therefore, in this review article, we discuss the structure and characteristics of TNF-α and its related receptors: TNF-α signaling, TNF-α-mediated inflammatory diseases as well as TNF-α inhibition strategies.

Tumor necrosis factor-alpha (TNF-α) is a pro-inflammatory cytokine produced by a variety of cells, including hematopoietic and non-hematopoietic cells, malignant cells, macrophages, B lymphocytes, T lymphocytes, natural killer cells, neutrophils, astrocytes, endothelial cells, and smooth muscle cells. TNF-α is a homo-trimeric molecular whose individual subunits are composed of antiparallel beta-sheets, forming a regular triangular prism shape. TNF-α binds to three receptor molecules through its receptor-binding sites, which are at the base of its pyramid structure. Biological responses to TNF-α are mediated through two different receptors: TNFR1 and TNFR2. These receptors are transmembrane glycoproteins with extracellular domains containing multiple cysteine-rich repeats that are structurally and functionally homologous, and the intracellular domains that are discrete and transduce their signals through both overlapping and distinct pathways. However, though TNF-α was initially discovered as an anti-tumor agent, it has been revealed that TNF-α and other ligands of this family are involved in some diseases like cancer, neurological, pulmonary, cardiovascular and autoimmune diseases and metabolic disorders. In general, TNF-α activates the control systems involved in cell proliferation, differentiation, inflammation and cell death, and the regulation of immune system. Although a normal level of TNF-α is very important for the regulation of immune responses, the persistence of the immune response as a result of inappropriate and excessive production of TNF-α can cause some inflammatory or autoimmune diseases. Accordingly, either neutralization TNF-α or blockade of its receptors using TNF-α inhibitors can be an effective therapeutic strategy to prevent or treat such inflammatory diseases. Several methods have been used to inhibit TNF-α, including the production of chimeric or fully human antibodies, soluble TNF-α receptors, or anti-TNF-α small molecules. The two previous agents are mostly capable of inhibiting the binding of TNF-α to its associated receptors, while anti-TNF-α small molecules, in addition to the above, inhibit the biosynthesis of TNF-α by blocking TNF-α mRNA biosynthesis, through the inhibition of its post-translational processing, or by blocking TNF-α receptors. Therefore, in this review article, we discuss the structure and characteristics of TNF-α and its related receptors: TNF-α signaling, TNFα-mediated inflammatory diseases as well as TNF-α inhibition strategies. [ABSTRACT FROM AUTHOR]

To improve the quality requirements for copper deposits, the influence of some inhibition agents added to the acidic copper bath has been studied. Several aromatic nitrogen compounds have been tested as inhibition agents, such as aniline, N-methylaniline, N-ethylaniline, N, N-dimethylaniline (DMA), and N, N-diethylaniline (DEA). The electrochemical behavior of these organic additives and the most relevant aspects of the electrochemical behavior of copper in acid solutions have been analyzed by cyclic voltammetry. At the same time, a correlation between voltammetric data and molecular properties of protonated amines obtained by molecular modeling has been performed. The morphology of the copper deposits obtained in the absence and presence of organic compounds has been studied by scanning electron microscopy. An improvement of the roughness degree and crystallite size upon addition of aromatic amine has been found. Best results were obtained for DMA and DEA working at room temperature (25 ± 0.1 °C) and 200 A m current density, in 1 mol L sulfuric acid solution with 50 g L Cu. [ABSTRACT FROM AUTHOR]