284 research outputs found
Variants in the estrogen receptor alpha gene and its mRNA contribute to risk for schizophrenia
Estrogen modifies human emotion and cognition and impacts symptoms of schizophrenia. We hypothesized that the variation in the estrogen receptor alpha (ESR1) gene and cortical ESR1 mRNA is associated with schizophrenia. In a small case–control genetic association analysis of postmortem brain tissue, genotype CC (rs2234693) and haplotypes containing the C allele of a single-nucleotide polymorphism (SNP) in intron1 (PvuII) were more frequent in African American schizophrenics (P = 0.01–0.001). In a follow-up family-based association analysis, we found overtransmission of PvuII allele C and a PvuII C-containing haplotype (P = 0.01–0.03) to African American and Caucasian patients with schizophrenia. Schizophrenics with the ‘at risk’ PvuII genotype had lower ESR1 mRNA levels in the frontal cortex. Eighteen ESR1 splice variants and decreased frequencies of the wild-type ESR1 mRNA were detected in schizophrenia. In one patient, a unique ESR1 transcript with a genomic insert encoding a premature stop codon and a truncated ESR1 protein lacking most of the estrogen binding domain was the only transcript detected. Using a luciferase assay, we found that mRNA encoding a truncated ESR1 significantly attenuates gene expression at estrogen-response elements demonstrating a dominant negative function. An intron 6 SNP [rs2273207(G)] was associated with an ESR1 splice variant missing exon seven. The T allele of another intron 6 SNP was part of a 3′ haplotype less common in schizophrenia [rs2273206(T), rs2273207(G), rs2228480(G)]. Thus, the variation in the ESR1 gene is associated with schizophrenia and the mechanism of this association may involve alternative gene regulation and transcript processing
From Tetraquark to Hexaquark: A Systematic Study of Heavy Exotics in the Large Limit
A systematic study of multiquark exotics with one or heavy quarks in
the large limit is presented. By binding a chiral soliton to a heavy
meson, either a normal -quark baryon or an exotic -quark baryon
is obtained. By replacing the heavy quark with heavy antiquarks, exotic
-quark and -quark mesons are obtained. When , they are
just the normal triquark baryon , the exotic pentaquark baryon , tetraquark di-meson and the hexaquark
di-baryon respectively. Their
stabilities and decays are also discussed. In particular, it is shown that the
``heavy to heavy'' semileptonic decays are described by the Isgur--Wise form
factors of the normal baryons.Comment: 14 pages in REVTeX, no Figure
Dysregulated protocadherin-pathway activity as an intrinsic defect in induced pluripotent stem cell-derived cortical interneurons from subjects with schizophrenia.
We generated cortical interneurons (cINs) from induced pluripotent stem cells derived from 14 healthy controls and 14 subjects with schizophrenia. Both healthy control cINs and schizophrenia cINs were authentic, fired spontaneously, received functional excitatory inputs from host neurons, and induced GABA-mediated inhibition in host neurons in vivo. However, schizophrenia cINs had dysregulated expression of protocadherin genes, which lie within documented schizophrenia loci. Mice lacking protocadherin-α showed defective arborization and synaptic density of prefrontal cortex cINs and behavioral abnormalities. Schizophrenia cINs similarly showed defects in synaptic density and arborization that were reversed by inhibitors of protein kinase C, a downstream kinase in the protocadherin pathway. These findings reveal an intrinsic abnormality in schizophrenia cINs in the absence of any circuit-driven pathology. They also demonstrate the utility of homogenous and functional populations of a relevant neuronal subtype for probing pathogenesis mechanisms during development
Direct identification of clinically relevant neoepitopes presented on native human melanoma tissue by mass spectrometry
Although mutations may represent attractive targets for immunotherapy, direct identification of mutated peptide ligands isolated from human leucocyte antigens (HLA) on the surface of native tumour tissue has so far not been successful. Using advanced mass spectrometry (MS) analysis, we survey the melanoma-associated immunopeptidome to a depth of 95,500 patient-presented peptides. We thereby discover a large spectrum of attractive target antigen candidates including cancer testis antigens and phosphopeptides. Most importantly, we identify peptide ligands presented on native tumour tissue samples harbouring somatic mutations. Four of eleven mutated ligands prove to be immunogenic by neoantigen-specific T-cell responses. Moreover, tumour-reactive T cells with specificity for selected neoantigens identified by MS are detected in the patient's tumour and peripheral blood. We conclude that direct identification of mutated peptide ligands from primary tumour material by MS is possible and yields true neoepitopes with high relevance for immunotherapeutic strategies in cancer
The Moving Junction Protein RON8 Facilitates Firm Attachment and Host Cell Invasion in Toxoplasma gondii
The apicomplexan moving junction (MJ) is a highly conserved structure formed during host cell entry that anchors the invading parasite to the host cell and serves as a molecular sieve of host membrane proteins that protects the parasitophorous vacuole from host lysosomal destruction. While recent work in Toxoplasma and Plasmodium has reinforced the composition of the MJ as an important association of rhoptry neck proteins (RONs) with micronemal AMA1, little is known of the precise role of RONs in the junction or how they are targeted to the neck subcompartment. We report the first functional analysis of a MJ/RON protein by disrupting RON8 in T. gondii. Parasites lacking RON8 are severely impaired in both attachment and invasion, indicating that RON8 enables the parasite to establish a firm clasp on the host cell and commit to invasion. The remaining junction components frequently drag in trails behind invading knockout parasites and illustrate a malformed complex without RON8. Complementation of Δron8 parasites restores invasion and reveals a processing event at the RON8 C-terminus. Replacement of an N-terminal region of RON8 with a mCherry reporter separates regions within RON8 that are necessary for rhoptry targeting and complex formation from those required for function during invasion. Finally, the invasion defects in Δron8 parasites seen in vitro translate to radically impaired virulence in infected mice, promoting a model in which RON8 has a crucial and unprecedented task in committing Toxoplasma to host cell entry
European Ultrahigh-Field Imaging Network for Neurodegenerative Diseases (EUFIND).
INTRODUCTION: The goal of European Ultrahigh-Field Imaging Network in Neurodegenerative Diseases (EUFIND) is to identify opportunities and challenges of 7 Tesla (7T) MRI for clinical and research applications in neurodegeneration. EUFIND comprises 22 European and one US site, including over 50 MRI and dementia experts as well as neuroscientists. METHODS: EUFIND combined consensus workshops and data sharing for multisite analysis, focusing on 7 core topics: clinical applications/clinical research, highest resolution anatomy, functional imaging, vascular systems/vascular pathology, iron mapping and neuropathology detection, spectroscopy, and quality assurance. Across these topics, EUFIND considered standard operating procedures, safety, and multivendor harmonization. RESULTS: The clinical and research opportunities and challenges of 7T MRI in each subtopic are set out as a roadmap. Specific MRI sequences for each subtopic were implemented in a pilot study presented in this report. Results show that a large multisite 7T imaging network with highly advanced and harmonized imaging sequences is feasible and may enable future multicentre ultrahigh-field MRI studies and clinical trials. DISCUSSION: The EUFIND network can be a major driver for advancing clinical neuroimaging research using 7T and for identifying use-cases for clinical applications in neurodegeneration
Measurement of inclusive D*+- and associated dijet cross sections in photoproduction at HERA
Inclusive photoproduction of D*+- mesons has been measured for photon-proton
centre-of-mass energies in the range 130 < W < 280 GeV and a photon virtuality
Q^2 < 1 GeV^2. The data sample used corresponds to an integrated luminosity of
37 pb^-1. Total and differential cross sections as functions of the D*
transverse momentum and pseudorapidity are presented in restricted kinematical
regions and the data are compared with next-to-leading order (NLO) perturbative
QCD calculations using the "massive charm" and "massless charm" schemes. The
measured cross sections are generally above the NLO calculations, in particular
in the forward (proton) direction. The large data sample also allows the study
of dijet production associated with charm. A significant resolved as well as a
direct photon component contribute to the cross section. Leading order QCD
Monte Carlo calculations indicate that the resolved contribution arises from a
significant charm component in the photon. A massive charm NLO parton level
calculation yields lower cross sections compared to the measured results in a
kinematic region where the resolved photon contribution is significant.Comment: 32 pages including 6 figure
Highlights from the Pierre Auger Observatory
The Pierre Auger Observatory is the world's largest cosmic ray observatory.
Our current exposure reaches nearly 40,000 km str and provides us with an
unprecedented quality data set. The performance and stability of the detectors
and their enhancements are described. Data analyses have led to a number of
major breakthroughs. Among these we discuss the energy spectrum and the
searches for large-scale anisotropies. We present analyses of our X
data and show how it can be interpreted in terms of mass composition. We also
describe some new analyses that extract mass sensitive parameters from the 100%
duty cycle SD data. A coherent interpretation of all these recent results opens
new directions. The consequences regarding the cosmic ray composition and the
properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray
Conference, Rio de Janeiro 201
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