First isolation of Dysgonomonas mossii from intestinal juice of a patient with pancreatic cancer

ArticleARCHIVES OF MEDICAL RESEARCH. 37(7): 914-916 (2006)journal articl

GATA2 Mediates Thyrotropin-Releasing Hormone-Induced Transcriptional Activation of the Thyrotropin β Gene

Thyrotropin-releasing hormone (TRH) activates not only the secretion of thyrotropin (TSH) but also the transcription of TSHβ and α-glycoprotein (αGSU) subunit genes. TSHβ expression is maintained by two transcription factors, Pit1 and GATA2, and is negatively regulated by thyroid hormone (T3). Our prior studies suggest that the main activator of the TSHβ gene is GATA2, not Pit1 or unliganded T3 receptor (TR). In previous studies on the mechanism of TRH-induced activation of the TSHβ gene, the involvements of Pit1 and TR have been investigated, but the role of GATA2 has not been clarified. Using kidney-derived CV1 cells and pituitary-derived GH3 and TαT1 cells, we demonstrate here that TRH signaling enhances GATA2-dependent activation of the TSHβ promoter and that TRH-induced activity is abolished by amino acid substitution in the GATA2-Zn finger domain or mutation of GATA-responsive element in the TSHβ gene. In CV1 cells transfected with TRH receptor expression plasmid, GATA2-dependent transactivation of αGSU and endothelin-1 promoters was enhanced by TRH. In the gel shift assay, TRH signal potentiated the DNA-binding capacity of GATA2. While inhibition by T3 is dominant over TRH-induced activation, unliganded TR or the putative negative T3-responsive element are not required for TRH-induced stimulation. Studies using GH3 cells showed that TRH-induced activity of the TSHβ promoter depends on protein kinase C but not the mitogen-activated protein kinase, suggesting that the signaling pathway is different from that in the prolactin gene. These results indicate that GATA2 is the principal mediator of the TRH signaling pathway in TSHβ expression

Jahn-Teller Effect of Cu-Ferrite Films by Solid Reaction

Copper iron oxide (CuFe2O4 : Cu-ferrite) thin film was prepared on a glass substrate by vacuum evaporation and solid reaction, and annealed at 400 °C in the air. The obtained film was identified by X-ray diffraction analysis as Cu-ferrite film having a tetragonal lattice. The axial ratio (c/a) of the film was 1.507 and was larger than that of ASTM data because the lattice distortion of the films seems to be large by difference of a preparation method. The temperature dependence of the magnetization and conductivities of the film showed remarkable changes at about 360°C, which were considered to be caused by phase transition due to the Jahn-Teller effect