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The SWI/SNF chromatin remodeling complex is a master regulator of developmental cell-fate decisions, although the key target pathways are poorly characterized. Here, we interrogated the contribution of the SWI/SNF subunit and tumor suppressor SNF5 to the regulation of developmental pathways using conditional mouse and cell culture models. We find that loss of SNF5 phenocopies β-catenin hyperactivation and that SNF5 is essential for regulating Wnt/β-catenin pathway target expression. These data provide insight into chromatin-based mechanisms that underlie developmental regulation and elucidate the emerging theme that mutation of this tumor suppressor complex can activate developmental pathways by uncoupling them from upstream control. [ABSTRACT FROM AUTHOR]

Objective To determine, in mice with disrupted Müllerian inhibiting substance (MIS) receptor genes, whether MIS affects gubernacular development; MIS causes Müllerian duct regression and is proposed to be involved in the first stage of testicular descent, because gubernacular development is abnormal in humans with persistent Müllerian duct syndrome. Materials and methods Ten wild-type, 11 heterozygotic and 12 homozygotic mice for MIS receptor mutations were killed at 17.5 or 18.5 days after conception or at birth, to provide serial sagittal sections of the pelvis. The amount of cremaster muscle, mitotic bodies in the gubernacular bulb, and gubernacular size were quantified by computer analysis (four mice/group). Results Müllerian ducts were present in the homozygous mutants, partially present in the heterozygotes and absent in the wild-type controls. All mice had descended testes. The cremaster muscle was significantly less developed in homozygous mutants than in wild-type controls (P < 0.001) and heterozygotes (P < 0.01) at birth. The mitotic index between the gubernacula of all groups was indistinguishable. There was no statistical difference in gubernacular area amongst the groups. Poor cremaster muscle development in homozygous mutants gave the muscle a loose mesenchymal appearance. Conclusions Although there was an observable effect on cremaster muscle development in these mutant mice, gubernacular development and testicular descent were otherwise normal, and thus there must be other reasons for the observed differences in humans with persistent Müllerian duct syndrome. [ABSTRACT FROM AUTHOR]

Background: Hyperoxia or clinical oxygen (O2) therapy is known to result in increased oxidative burden. Therefore, understanding susceptibility to hyperoxia exposure is clinically important. Bone morphogenetic proteins (BMPs) 2 and 4 are involved in cardiac development and may influence responses to hyperoxia. Methods. Bmp2+/−. Bmp4+/− and wild-type mice were exposed to hyperoxia (100% O2) for 24 hrs. Electrocardiograms (ECG) were recorded before and during exposure by radio-telemetry. Results: At baseline, a significantly higher low frequency (LF) and total power (TP) heart rate variability (HRV) were found in Bmp2+/− mice only ( p < 0.05). Twenty-four hours hyperoxia-induced strain-independent reductions in heart rate, QTcB and ST-interval and increases in QRS, LF HRV and standard deviation of RR-intervals were observed. In Bmp4+/− mice only, increased PR-interval (PR-I) (24 hrs), P-wave duration (P-d; 18 and 21-24 hrs), PR-I minus P-d (PR - Pd; 24 hrs) and root of the mean squared differences of successive RR-intervals (24 hrs) were found during hyperoxia ( p < 0.05). Discussion: Elevated baseline LF and TP HRV in Bmp2+/− mice suggests an altered autonomic nervous system regulation of cardiac function in these mice. However, this was not related to strain specific differences in responses to 24 hrs hyperoxia. During hyperoxia, Bmp4+/− mice were the most susceptible in terms of atrioventricular conduction changes and risk of atrial fibrillation, which may have important implications for patients treated with O2 who also harbor Bmp4 mutations. This study demonstrates significant ECG and HRV responses to 24 hrs hyperoxia in mice, which highlights the need to further work on the genetic mechanisms associated with cardiac susceptibility to hyperoxia. [ABSTRACT FROM AUTHOR]

Abstract: The Double Chooz is a reactor neutrino experiment which measures the last unknown neutrino mixing angle . The Double Chooz experiment uses two identical detectors placed at sites far and near from Chooz reactor cores. The detector uses 390 low-background and high performance 10-in. Photo-Multiplier Tubes (PMTs) to detect scintillation light from gadolinium loaded liquid scintillator. In order to test and characterize the PMTs and to tune operation parameter, we developed two types of PMT test system and evaluated 400PMTs before installation. Those PMTs fulfilled our requirements and half of them were installed in the far detector in 2009 and physics data have been successfully taken since 2011. [Copyright &y& Elsevier]

This study describes a multifunctional envelope-type nano device (MEND) that mimics an envelope-type virus based on a novel packaging strategy. MEND particles contain a DNA core packaged into a lipid envelope modified with an octaarginine peptide. The peptide mediates internalization via macropinocytosis, which avoids lysosomal degradation. MEND-mediated transfection of a luciferase expression plasmid achieved comparable efficiency to adenovirus-mediated transfection, with lower associated cytotoxicity. Furthermore, topical application of MEND particles containing constitutively active bone morphogenetic protein (BMP) type IA receptor (caBmpr1a) gene had a significant impact on hair growth in vivo. These data demonstrate that MEND is a promising non-viral gene delivery system that may provide superior results to existing non-viral gene delivery technologies.Gene Therapy (2007) 14, 682–689. doi:10.1038/sj.gt.3302910; published online 1 February 2007 [ABSTRACT FROM AUTHOR]