TCF19

Transcription factor 19 is a protein that in humans is encoded by the TCF19 gene.

References

Further reading

CEBPB

CCAAT/enhancer-binding protein beta is a protein that in humans is encoded by the CEBPB gene.

Function

The protein encoded by this intronless gene is a bZIP transcription factor that can bind as a homodimer to certain DNA regulatory regions. It can also form heterodimers with the related proteins CEBP-alpha, CEBP-delta, and CEBP-gamma. The encoded protein is important in the regulation of genes involved in immune and inflammatory responses and has been shown to bind to the IL-1 response element in the IL-6 gene, as well as to regulatory regions of several acute-phase and cytokine genes. In addition, the encoded protein can bind the promoter and upstream element and stimulate the expression of the collagen type I gene.

CEBP-beta is critical for normal macrophage functioning, an important immune cell sub-type; mice unable to express CEBP-beta have macrophages that cannot differentiate (specialize) and thus are unable to perform all their biological functions - including macrophage-mediated muscle repair.Observational work has shown that expression of CEBP-beta in blood leukocytes is positively associated with muscle strength in humans, emphasizing the importance of the immune system, and particularly macrophages, in the maintenance of muscle function.

Technetium hexafluoride

Technetium hexafluoride or technetium(VI) fluoride (TcF₆) is a yellow inorganic compound with a low melting point. It was first identified in 1961. In this compound, technetium has an oxidation state of +6, the highest oxidation state found in the technetium halides. The other such compound is technetium(VI) chloride, TcCl₆. In this respect, technetium differs from rhenium, which forms a heptafluoride, ReF₇. Technetium hexafluoride occurs as an impurity in uranium hexafluoride, as technetium is a fission product of uranium.

Preparation

Technetium hexafluoride is prepared by heating technetium metal with an excess of F₂ at 400 °C.

Description

Technetium hexafluoride is a golden-yellow solid at room temperature. Its melting point is 37.4 °C and its boiling point is 55.3 °C.

Technetium hexafluoride undergoes a solid phase transition at −4.54 °C. Above this temperature (measured at 10 °C), the solid structure is cubic. Lattice parameters are a = 6.16 Å. There are two formula units (in this case, discrete molecules) per unit cell, giving a density of 3.02 g·cm⁻³. Below this temperature (measured at −19 °C), the solid structure is orthorhombic space group Pnma. Lattice parameters are a = 9.55 Å, b = 8.74 Å, and c = 5.02 Å. There are four formula units (in this case, discrete molecules) per unit cell, giving a density of 3.38 g·cm⁻³. At −140 °C, the solid structure is still orthothombic, but the lattice parameters are now a = 9.360 Å, b = 8.517 Å, and c = 4.934 Å, giving a density of 3.58 g·cm⁻³.