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Dual and opposing roles of primary cilia in medulloblastoma development.
Recent work has shown that primary cilia are essential for Hedgehog (Hh) signaling during mammalian development. It is also known that aberrant Hh signaling can lead to cancer, but the role of primary cilia in oncogenesis is not known. Cerebellar granule neuron precursors (GNPs) can give rise to medulloblastomas, the most common malignant brain tumor in children. The primary cilium and Hh signaling are required for GNP proliferation. We asked whether primary cilia in GNPs have a role in medulloblastoma growth in mice. Genetic ablation of primary cilia blocked medulloblastoma formation when this tumor was driven by a constitutively active Smoothened protein (Smo), an upstream activator of Hh signaling. In contrast, removal of cilia was required for medulloblastoma growth by a constitutively active glioma-associated oncogene family zinc finger-2 (GLI2), a downstream transcription factor. Thus, primary cilia are either required for or inhibit medulloblastoma formation, depending on the initiating oncogenic event. Remarkably, the presence or absence of cilia was associated with specific variants of human medulloblastomas; primary cilia were found in medulloblastomas with activation in HH or WNT signaling but not in most medulloblastomas in other distinct molecular subgroups. Primary cilia could serve as a diagnostic tool and provide new insights into the mechanism of tumorigenesis
Cross-talk between epidermal growth factor receptor and protein kinase C during calcium-induced differentiation of keratinocytes
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74029/1/j.1600-0625.2000.009003192.x.pd
Documented spatial data set containing the subdivision of the basins into groundwater systems and subsystems, the selected locations per subsystem and a description of these sites, available data and projected additional measurements and equipment
The establishment of tools for trends analysis in groundwater is
essential for the prediction and evaluation of measures taken within
context of the Water Framework Directive and the draft Groundwater
Directive. This report describes the spatial data sets which will be
used for the purpose of detection, aggregation and extrapolation of
temporal trends in groundwater quality. Trend analysis methods will
be applied and tested at various scales and in various
hydrogeological situations. The report contains a description of the
studied sub-basins in TREND 2, including information on
hydrogeology, land use and pressures, available data and projected
additional measurements. Major differences between the sub-basins
and the data sets are described to examine consequences for the
work on trend detection. One of the challenges for TREND 2 is to
define criteria for the application of various statistical and
deterministic trend approaches for a range of hydrogeological
conditions, spatial scales and types of groundwater monitoring. An
overview of these conditions, scales and monitoring types is provided
in the present report.FP6 Integrated Project AquaTerra Integrated Modelling of the river-sediment-soil-groundwater system; advanced tools for the management of catchment areas and river basins in the context of global change (Project no. 505428 - GOCE
Ibrutinib does not have clinically relevant interactions with oral contraceptives or substrates of CYP3A and CYP2B6
Ibrutinib may inhibitintestinal CYP3A4 and induce CYP2B6 and/or CYP3A. Secondary
to potential induction, ibrutinib may reduce the exposure and effectiveness of oral
contraceptives (OCs). This phase I study evaluated the effect of ibrutinib on the pharmacokinetics of the CYP2B6 substrate bupropion, CYP3A substrate midazolam, and
OCs ethinylestradiol (EE) and levonorgestrel (LN). Female patients (N = 22) with B-cell
malignancies received single doses of EE/LN (30/150 μg) and bupropion/midazolam
(75/2 mg) during a pretreatment phase on days 1 and 3, respectively (before starting ibrutinib on day 8), and again after ibrutinib 560 mg/day for ≥ 2 weeks. Intestinal
CYP3A inhibition was assessed on day 8 (single-dose ibrutinib plus single-dose midazolam). Systemic induction was assessed at steady-state on days 22 (EE/LN plus ibrutinib) and 24 (bupropion/midazolam plus ibrutinib). The geometric mean ratios (GMRs;
test/reference) for maximum plasma concentration (Cmax) and area under the plasma
concentration-time curve (AUC) were derived using linear mixed-effects models (90%
confidence interval within 80%-125% indicated no interaction). On day 8, the GMR
for midazolam exposure with ibrutinib coadministration was ≤ 20% lower than the reference, indicating lack of intestinal CYP3A4 inhibition. At ibrutinib steady-state, the
Cmax and AUC of EE were 33% higher than the reference, which was not considered
clinically relevant. No substantial changes were noted for LN, midazolam, or bupropion. No unexpected safety findings were observed. A single dose of ibrutinib did not
inhibit intestinal CYP3A4, and repeated administration did not induce CYP3A4/2B6,
as assessed using EE, LN, midazolam, and bupropion
Exploring the genetics of irritable bowel syndrome: A GWA study in the general population and replication in multinational case-control cohorts
OBJECTIVE:
IBS shows genetic predisposition, but adequately powered gene-hunting efforts have been scarce so far. We sought to identify true IBS genetic risk factors by means of genome-wide association (GWA) and independent replication studies.
DESIGN:
We conducted a GWA study (GWAS) of IBS in a general population sample of 11\u2005326 Swedish twins. IBS cases (N=534) and asymptomatic controls (N=4932) were identified based on questionnaire data. Suggestive association signals were followed-up in 3511 individuals from six case-control cohorts. We sought genotype-gene expression correlations through single nucleotide polymorphism (SNP)-expression quantitative trait loci interactions testing, and performed in silico prediction of gene function. We compared candidate gene expression by real-time qPCR in rectal mucosal biopsies of patients with IBS and controls.
RESULTS:
One locus at 7p22.1, which includes the genes KDELR2 (KDEL endoplasmic reticulum protein retention receptor 2) and GRID2IP (glutamate receptor, ionotropic, delta 2 (Grid2) interacting protein), showed consistent IBS risk effects in the index GWAS and all replication cohorts and reached p=9.31
710(-6) in a meta-analysis of all datasets. Several SNPs in this region are associated with cis effects on KDELR2 expression, and a trend for increased mucosal KDLER2 mRNA expression was observed in IBS cases compared with controls.
CONCLUSIONS:
Our results demonstrate that general population-based studies combined with analyses of patient cohorts provide good opportunities for gene discovery in IBS. The 7p22.1 and other risk signals detected in this study constitute a good starting platform for hypothesis testing in future functional investigations.
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Coupling Constant pH Molecular Dynamics with Accelerated Molecular Dynamics
An extension of the constant pH method originally implemented by Mongan et al. (J. Comput. Chem.2004, 25, 2038−2048) is proposed in this study. This adapted version of the method couples the constant pH methodology with the enhanced sampling technique of accelerated molecular dynamics, in an attempt to overcome the sampling issues encountered with current standard constant pH molecular dynamics methods. Although good results were reported by Mongan et al. on application of the standard method to the hen egg-white lysozyme (HEWL) system, residues which possess strong interactions with neighboring groups tend to converge slowly, resulting in the reported inconsistencies for predicted pKa values, as highlighted by the authors. The application of the coupled method described in this study to the HEWL system displays improvements over the standard version of the method, with the improved sampling leading to faster convergence and producing pKa values in closer agreement to those obtained experimentally for the more slowly converging residues
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