The Rh oxide ultrathin film on Rh(100): an x-ray photoelectron diffraction study.

The surface and interface structure of the RhO(2) ultrathin film grown on Rh(100) is investigated by means of x-ray photoelectron diffraction. Experimental and simulated one- and two-dimensional angular distribution intensities of the O1s and Rh3d(5/2) chemically shifted core levels are quantitatively analyzed. The previously proposed O-Rh-O trilayer model is independently confirmed. A rippled buckling of the metal surface is observed at the oxide-metal interface, with a mean interfacial Rh-O distance which is 0.2 Å larger with respect to previous findings. The link between the local atomic rearrangement and the overall geometric and electronic properties of the oxide is discussed on the basis of a thorough comparison with the corresponding RhO(2) rutile structure.

TL1A modulates the severity of colitis by promoting Th9 differentiation and IL-9 secretion.

AIMS: TL1A was reported to contribute to the susceptibility to ulcerative colitis (UC). However, the molecular mechanisms of TL1A in UC development are poorly understood. We aimed to investigate the role of TL1A in colitis, and reveal the regulatory mechanism of TL1A in chronic colitis development. MAIN METHODS: Wild-type mice and transgenic mice with overexpressing TL1A in lymphocytes were used to construct chronic DSS colitis models. To investigate the molecular mechanism in vitro, CD4+ T cells were sorted from spleens and mesenteric lymph node cells to induce Th9 cells. Biopsy specimens from ulcerative colitis patients were collected for in vivo validation. KEY FINDINGS: The elevated TL1A expression in chronic DSS colitis models exacerbated intestinal inflammation. The differentiation of Th9 cells, IL-9 secretion and production of TGF-ß, IL-4 and PU.1 was significantly enhanced in transgenic mice with TL1A overexpression. In vitro results showed that TL1A enhanced the Th9 cells, IL-9 and PU.1 production, while TL1A antibodies inhibited their production. In human translational studies, patients with ulcerative colitis with elevated TL1A expression also exhibited more serious inflammation with higher levels of Th9 cells, IL-9 and PU.1 expression. SIGNIFICANCE: We presented a possible mechanism of TL1A in UC development that TL1A may promote the differentiation of Th9 cells and enhanced IL-9 secretion by up-regulating the expression of TGF-ß, IL-4 and PU.1, which provided a novel perspective to study the UC pathogenesis, and indicated that targeting of TL1A signal pathway may by a likely strategy for the treatment of chronic colitis.