Weak ferromagnetism of quasi-one-dimensional S=1/2 antiferromagnet BaCu2_2Ge2_2O7_7

Weak ferromagnetism of quasi-one-dimensional S = 1/2 antiferromagnet BaCu$_2$Ge$_2$O$_7$ is studied by the magnetization measurement. The spontaneous magnetization appears along the b axis. The local symmetry between the in-chain nearest neighbor spins allows the presence of Dzyaloshinskii-Moriya interaction, and the only possible spatial configuration of the weak ferromagnetic moment per spin determines the sign of the inter-chain interaction. A weak $a$-axis magnetic field can change the direction of the magnetization to the $a$-axis direction, which shows that the spin chain forms a weakly coupled weak-ferromagnetic chain system.Comment: 10 pages, 4 figure

Aberrant chromatin landscape following loss of the H3.3 chaperone Daxx in haematopoietic precursors leads to Pu.1-mediated neutrophilia and inflammation

Defective silencing of retrotransposable elements has been linked to inflammageing, cancer and autoimmune diseases. However, the underlying mechanisms are only partially understood. Here we implicate the histone H3.3 chaperone Daxx, a retrotransposable element repressor inactivated in myeloid leukaemia and other neoplasms, in protection from inflammatory disease. Loss of Daxx alters the chromatin landscape, H3.3 distribution and histone marks of haematopoietic progenitors, leading to engagement of a Pu.1-dependent transcriptional programme for myelopoiesis at the expense of B-cell differentiation. This causes neutrophilia and inflammation, predisposing mice to develop an autoinflammatory skin disease. While these molecular and phenotypic perturbations are in part reverted in animals lacking both Pu.1 and Daxx, haematopoietic progenitors in these mice show unique chromatin and transcriptome alterations, suggesting an interaction between these two pathways. Overall, our findings implicate retrotransposable element silencing in haematopoiesis and suggest a cross-talk between the H3.3 loading machinery and the pioneer transcription factor Pu.1

Chiral Heterocyclic Ligands. XI. Self-assembly and X-Ray Crystal Structures of Chiral Silver Coordination Polymers of (S)-(-)-Nicotine

Three chiral coordination polymers have been prepared by reaction of (S)-(-)-nicotine with silver(I) salts. X-Ray crystal structure determinations revealed that these all contain polymer chains in which the nicotine molecule acts as a bridging ligand between four-coordinate silver atoms. In one case additional bridging by nitrate anions leads to a three-dimensional network structure

Identification of stanniocalcin 2 as prognostic marker in renal cell carcinoma

BACKGROUND: For an individualized therapy in renal cell carcinoma (RCC), there is a clear need for novel prognostic biomarkers to ensure adequate risk stratification and help with the choice of therapy options. OBJECTIVE: To identify new secreted biomarkers for diagnosis and estimation of prognosis in RCC. DESIGN, SETTING, AND PARTICIPANTS: A meta-analysis of published microarray data was performed. Stanniocalcin 2 (STC2), a glycoprotein hormone that is involved in regulatory effects on calcium and phosphate transport in the kidney, was found overexpressed in tumors and hence analyzed in detail. Kidney tissue samples derived from 108 patients with RCC undergoing radical nephrectomy between July 2003 and January 2006 were used to validate and estimate the potential of STC2 as a biomarker for RCC. MEASUREMENTS: STC2, found upregulated in clear cell RCC, was analyzed in detail using real-time reverse transcription-polymerase chain reaction (RT-PCR), western blotting, and immunohistochemistry. Furthermore, STC2 protein expression determined on a tissue microarray was correlated to clinical pathologic parameters, including patient survival. RESULTS AND LIMITATIONS: STC2 was upregulated at the mRNA and protein levels in RCC. In normal renal tissue, STC2 expression was limited to distal tubuli and glomeruli, whereas in tumor a strong cytoplasmic and also membranous staining was detected. STC2 expression was found in clear cell, chromophobe, and papillary RCC. Strong cytoplasmic STC2 expression was significantly associated with shorter patient survival in Kaplan-Meier analyses. In the group of patients without metastases, cytoplasmic STC2 expression was also found as a significant independent risk factor in multivariate analysis. A limitation of the study is the small number of patients. CONCLUSIONS: Increased cytoplasmic STC2 expression correlated with conventional indicators of aggressiveness of RCC and shorter overall patient survival times. STC2 could become an adjunct tissue biomarker that may be useful in the postoperative risk stratification of RCC patients