16 research outputs found

    Analyse der Tätigkeiten kardiovaskulärer Gewebebanken in Deutschland in den Jahren 2007 bis 2010

    Get PDF
    __Background:__ Especially in complicated aortic valve endocarditis, infections of the aorta by mycotic aortic aneurysms and prosthetic infections, or as part of the Ross procedure, the use of allogeneic heart valve transplants remains important. The production of such allografts in Germany is the task of cardiovascular tissue banks (CVTB). __Materials and methods:__ During an analysis of the years 2007-2010, basic data on donor numbers, production, and distribution as well as the technical conditions of not only the four participating CVTB (Bad Oeynhausen, Berlin, Kiel, Munich) but also data from the CVTB Rotterdam as an external reference were recorded. __Results:__ The German CVTB delivered an average of 44 aortic and 95 pulmonary allografts per year to clinical users. By incorporating the annually imported valve allografts, the demand in Germany approximately averages 220 heart valve allografts per year. The heart tissue was harvested from approximately 100 multiorgan donors, 45 cardiovascular deaths, and 80 domino donors annually. __Discussion:__ The participating cardiovascular tissue banks have comparable technical and administrative requirements and are able to produce tissue preparations according to the rules of Good Professional Practice in accordance with § 3 (3) AMWHV to assess their quality, whereby harmonization of microbiological monitoring and antibiotic treatment is still necessary

    Molecularly defined diffuse leptomeningeal glioneuronal tumor (DLGNT) comprises two subgroups with distinct clinical and genetic features

    Get PDF
    Diffuse leptomeningeal glioneuronal tumors (DLGNT) represent rare CNS neoplasms which have been included in the 2016 update of the WHO classification. The wide spectrum of histopathological and radiological features can make this enigmatic tumor entity difficult to diagnose. In recent years, large-scale genomic and epigenomic analyses have afforded insight into key genetic alterations occurring in multiple types of brain tumors and provide unbiased, complementary tools to improve diagnostic accuracy. Through genome-wide DNA methylation screening of > 25,000 tumors, we discovered a molecularly distinct class comprising 30 tumors, mostly diagnosed histologically as DLGNTs. Copy-number profiles derived from the methylation arrays revealed unifying characteristics, including loss of chromosomal arm 1p in all cases. Furthermore, this molecular DLGNT class can be subdivided into two subgroups [DLGNT methylation class (MC)-1 and DLGNT methylation class (MC)-2], with all DLGNT-MC-2 additionally displaying a gain of chromosomal arm 1q. Co-deletion of 1p/19q, commonly seen in IDH-mutant oligodendroglioma, was frequently observed in DLGNT, especially in DLGNT-MC-1 cases. Both subgroups also had recurrent genetic alterations leading to an aberrant MAPK/ERK pathway, with KIAA1549:BRAF fusion being the most frequent event. Other alterations included fusions of NTRK1/2/3 and TRIM33:RAF1, adding up to an MAPK/ERK pathway activation identified in 80% of cases. In the DLGNT-MC-1 group, age at diagnosis was significantly lower (median 5 vs 14 years, p < 0.01) and clinical course less aggressive (5-year OS 100, vs 43% in DLGNT-MC-2). Our study proposes an additional molecular layer to the current histopathological classification of DLGNT, of particular use for cases without typical morphological or radiological characteristics, such as diffuse growth and radiologic leptomeningeal dissemination. Recurrent 1p deletion and MAPK/ERK pathway activation represent diagnostic biomarkers and therapeutic targets, respectively—laying the foundation for future clinical trials with, e.g., MEK inhibitors that may improve the clinical outcome of patients with DLGNT

    Observation of one-way Einstein-Podolsky-Rosen steering

    Full text link
    The distinctive non-classical features of quantum physics were first discussed in the seminal paper by A. Einstein, B. Podolsky and N. Rosen (EPR) in 1935. In his immediate response E. Schr\"odinger introduced the notion of entanglement, now seen as the essential resource in quantum information as well as in quantum metrology. Furthermore he showed that at the core of the EPR argument is a phenomenon which he called steering. In contrast to entanglement and violations of Bell's inequalities, steering implies a direction between the parties involved. Recent theoretical works have precisely defined this property. Here we present an experimental realization of two entangled Gaussian modes of light by which in fact one party can steer the other but not conversely. The generated one-way steering gives a new insight into quantum physics and may open a new field of applications in quantum information.Comment: 4 pages, 4 figure

    Chlamydia trachomatis Co-opts GBF1 and CERT to Acquire Host Sphingomyelin for Distinct Roles during Intracellular Development

    Get PDF
    The obligate intracellular pathogen Chlamydia trachomatis replicates within a membrane-bound inclusion that acquires host sphingomyelin (SM), a process that is essential for replication as well as inclusion biogenesis. Previous studies demonstrate that SM is acquired by a Brefeldin A (BFA)-sensitive vesicular trafficking pathway, although paradoxically, this pathway is dispensable for bacterial replication. This finding suggests that other lipid transport mechanisms are involved in the acquisition of host SM. In this work, we interrogated the role of specific components of BFA-sensitive and BFA-insensitive lipid trafficking pathways to define their contribution in SM acquisition during infection. We found that C. trachomatis hijacks components of both vesicular and non-vesicular lipid trafficking pathways for SM acquisition but that the SM obtained from these separate pathways is being utilized by the pathogen in different ways. We show that C. trachomatis selectively co-opts only one of the three known BFA targets, GBF1, a regulator of Arf1-dependent vesicular trafficking within the early secretory pathway for vesicle-mediated SM acquisition. The Arf1/GBF1-dependent pathway of SM acquisition is essential for inclusion membrane growth and stability but is not required for bacterial replication. In contrast, we show that C. trachomatis co-opts CERT, a lipid transfer protein that is a key component in non-vesicular ER to trans-Golgi trafficking of ceramide (the precursor for SM), for C. trachomatis replication. We demonstrate that C. trachomatis recruits CERT, its ER binding partner, VAP-A, and SM synthases, SMS1 and SMS2, to the inclusion and propose that these proteins establish an on-site SM biosynthetic factory at or near the inclusion. We hypothesize that SM acquired by CERT-dependent transport of ceramide and subsequent conversion to SM is necessary for C. trachomatis replication whereas SM acquired by the GBF1-dependent pathway is essential for inclusion growth and stability. Our results reveal a novel mechanism by which an intracellular pathogen redirects SM biosynthesis to its replicative niche

    Acetylcholine receptor (AChR) clustering is regulated both by glycogen synthase kinase 3β (GSK3β)-dependent Phosphorylation and the level of CLIP-associated protein 2 (CLASP2) mediating the capture of microtubule plus-ends

    No full text
    The postsynaptic apparatus of the neuromuscular junction (NMJ) traps and anchors acetylcholine receptors (AChRs) at high density at the synapse. We have previously shown that microtubule (MT) capture by CLASP2, a MT plus-end-tracking protein (+TIP), increases the size and receptor density of AChR clusters at the NMJ through the delivery of AChRs and that this is regulated by a pathway involving neuronal agrin and several postsynaptic kinases, including GSK3. Phosphorylation by GSK3 has been shown to cause CLASP2 dissociation from MT ends, and nine potential phosphorylation sites for GSK3 have been mapped on CLASP2. How CLASP2 phosphorylation regulates MT capture at the NMJ and how this controls the size of AChR clusters are not yet understood. To examine this, we used myotubes cultured on agrin patches that induce AChR clustering in a two-dimensional manner. We show that expression of a CLASP2 mutant, in which the nine GSK3 target serines are mutated to alanine (CLASP2–9XS/9XA) and are resistant to GSK3β-dependent phosphorylation, promotes MT capture at clusters and increases AChR cluster size, compared with myotubes that express similar levels of wild type CLASP2 or that are noninfected. Conversely, myotubes expressing a phosphomimetic form of CLASP2 (CLASP2–8XS/D) show enrichment of immobile mutant CLASP2 in clusters, but MT capture and AChR cluster size are reduced. Taken together, our data suggest that both GSK3β-dependent phosphorylation and the level of CLASP2 play a role in the maintenance of AChR cluster size through the regulated capture and release of MT plus-ends

    Analysis of microtubule dynamic instability using a plus-end growth marker

    No full text
    Regulation of microtubule dynamics is essential for many cell biological processes, and is likely to be variable between different subcellular regions. We describe a computational approach to analyze microtubule dynamics by detecting growing microtubule plus ends. Our algorithm tracks all EB1-EGFP comets visible in an image time-lapse sequence allowing the detection of spatial patterns of microtubule dynamics. We use spatiotemporal clustering of EB1-EGFP growth tracks to infer microtubule behaviors during phases of pause and shortening. The algorithm was validated by comparison to manually tracked, homogeneously labeled microtubules, and by analysis of the effects of well-characterized inhibitors of microtubule polymerization dynamics. We used our method to analyze spatial variations of intracellular microtubule dynamics in migrating epithelial cells

    The E3 ligase TRIM1 ubiquitinates LRRK2 and controls its localization, degradation, and toxicity

    Get PDF
    Missense mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of familial Parkinson's disease (PD); however, pathways regulating LRRK2 subcellular localization, function, and turnover are not fully defined. We performed quantitative mass spectrometry-based interactome studies to identify 48 novel LRRK2 interactors, including the microtubule-associated E3 ubiquitin ligase TRIM1 (tripartite motif family 1). TRIM1 recruits LRRK2 to the microtubule cytoskeleton for ubiquitination and proteasomal degradation by binding LRRK2911-919, a nine amino acid segment within a flexible interdomain region (LRRK2853-981), which we designate the "regulatory loop" (RL). Phosphorylation of LRRK2 Ser910/Ser935 within LRRK2 RL influences LRRK2's association with cytoplasmic 14-3-3 versus microtubule-bound TRIM1. Association with TRIM1 modulates LRRK2's interaction with Rab29 and prevents upregulation of LRRK2 kinase activity by Rab29 in an E3-ligase-dependent manner. Finally, TRIM1 rescues neurite outgrowth deficits caused by PD-driving mutant LRRK2 G2019S. Our data suggest that TRIM1 is a critical regulator of LRRK2, controlling its degradation, localization, binding partners, kinase activity, and cytotoxicity

    PATZ1 fusions define a novel molecularly distinct neuroepithelial tumor entity with a broad histological spectrum

    Get PDF
    Large-scale molecular profiling studies in recent years have shown that central nervous system (CNS) tumors display a much greater heterogeneity in terms of molecularly distinct entities, cellular origins and genetic drivers than anticipated from histological assessment. DNA methylation profiling has emerged as a useful tool for robust tumor classification, providing new insights into these heterogeneous molecular classes. This is particularly true for rare CNS tumors with a broad morphological spectrum, which are not possible to assign as separate entities based on histological similarity alone. Here, we describe a molecularly distinct subset of predominantly pediatric CNS neoplasms (n = 60) that harbor PATZ1 fusions. The original histological diagnoses of these tumors covered a wide spectrum of tumor types and malignancy grades. While the single most common diagnosis was glioblastoma (GBM), clinical data of the PATZ1-fused tumors showed a better prognosis than typical GBM, despite frequent relapses. RNA sequencing revealed recurrent MN1:PATZ1 or EWSR1:PATZ1 fusions related to (often extensive) copy number variations on chromosome 22, where PATZ1 and the two fusion partners are located. These fusions have individually been reported in a number of glial/glioneuronal tumors, as well as extracranial sarcomas. We show here that they are more common than previously acknowledged, and together define a biologically distinct CNS tumor type with high expression of neural development markers such as PAX2, GATA2 and IGF2. Drug screening performed on the MN1:PATZ1 fusion-bearing KS-1 brain tumor cell line revealed preliminary candidates for further study. In summary, PATZ1 fusions define a molecular class of histologically polyphenotypic neuroepithelial tumors, which show an intermediate prognosis under current treatment regimens
    corecore