Institution
Free University of Berlin
Education•Berlin, Germany•
About: Free University of Berlin is a education organization based out in Berlin, Germany. It is known for research contribution in the topics: Population & Context (language use). The organization has 35195 authors who have published 66525 publications receiving 2094403 citations. The organization is also known as: FU Berlin.
Topics: Population, Context (language use), Excited state, Receptor, Politics
Papers published on a yearly basis
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TL;DR: A key role is identified for STXBP2 in lytic granule exocytosis in FHL-5 patients, where activity of natural killer and cytotoxic T cells was markedly reduced or absent, as determined by CD107 degranulation.
Abstract: Rapid intracellular transport and secretion of cytotoxic granules through the immunological synapse requires a balanced interaction of several proteins. Disturbance of this highly regulated process underlies familial hemophagocytic lymphohistiocytosis (FHL), a genetically heterogeneous autosomal-recessive disorder characterized by a severe hyperinflammatory phenotype. Here, we have assigned FHL-5 to a 1 Mb region on chromosome 19p by using high-resolution SNP genotyping in eight unrelated FHL patients from consanguineous families. Subsequently, we found nine different mutations, either truncating or missense, in STXBP2 in twelve patients from Turkey, Saudi Arabia, and Central Europe. STXBP2 encodes syntaxin binding protein 2 (Munc18-2), involved in the regulation of vesicle transport to the plasma membrane. We have identified syntaxin 11, a SNARE protein mutated in FHL-4, as an interaction partner of STXBP2. This interaction is eliminated by the missense mutations found in our FHL-5 patients, which leads to a decreased stability of both proteins, as shown in patient lymphocytes. Activity of natural killer and cytotoxic T cells was markedly reduced or absent, as determined by CD107 degranulation. Our findings thus identify a key role for STXBP2 in lytic granule exocytosis.
361 citations
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TL;DR: NPCs from neonatal mouse brains are isolated and infected with viral vectors expressing Oct4, Sox2, Klf4, and c‐Myc, suggesting that in vitro reprogramming is a universal process and that the combination of factors necessary for reprograming is dependent on cellular context.
Abstract: Expression of the transcription factors Oct4, Sox2, Klf4, and c-Myc in mesodermal and endodermal derivatives, including fibroblasts, lymphocytes, liver, stomach, and beta cells, generates induced pluripotent stem (iPS) cells. It remains unknown, however, whether cell types of the ectodermal lineage are equally amenable to reprogramming into iPS cells by the same combination of factors. To test this, we have isolated genetically marked neural progenitor cells (NPCs) from neonatal mouse brains and infected them with viral vectors expressing Oct4, Sox2, Klf4, and c-Myc. Infected NPCs gave rise to iPS cells that expressed markers of embryonic stem cells, showed demethylation of pluripotency genes, formed teratomas, and contributed to viable chimeras. In contrast to other somatic cell types, NPCs expressed high levels of endogenous Sox2 and thus did not require viral Sox2 expression for reprogramming into iPS cells. Our data show that in addition to mesoderm- and endoderm-derived cell types, neural progenitor cells of the ectodermal lineage can be reprogrammed into iPS cells, suggesting that in vitro reprogramming is a universal process. These results also imply that the combination of factors necessary for reprogramming is dependent on cellular context. Disclosure of potential conflicts of interest is found at the end of this article.
361 citations
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TL;DR: In this article, a reciprocal space analytical method was proposed to cut off the long range interactions in supercell calculations for systems that are infinite and periodic in one or two dimensions, generalizing previous work to treat finite systems.
Abstract: Received 23 December 2005; revised manuscript received 31 March 2006; published 26 May 2006 We present a reciprocal space analytical method to cut off the long range interactions in supercell calculations for systems that are infinite and periodic in one or two dimensions, generalizing previous work to treat finite systems. The proposed cutoffs are functions in Fourier space, that are used as a multiplicative factor to screen the bare Coulomb interaction. The functions are analytic everywhere except in a subdomain of the Fourier space that depends on the periodic dimensionality. We show that the divergences that lead to the nonanalytical behavior can be exactly canceled when both the ionic and the Hartree potential are properly screened. This technique is exact, fast, and very easy to implement in already existing supercell codes. To illustrate the performance of the scheme, we apply it to the case of the Coulomb interaction in systems with reduced periodicity as one-dimensional chains and layers. For these test cases, we address the impact of the cutoff on different relevant quantities for ground and excited state properties, namely: the convergence of the ground state properties, the static polarizability of the system, the quasiparticle corrections in the GW scheme, and the binding energy of the excitonic states in the Bethe-Salpeter equation. The results are very promising and easy to implement in all available first-principles codes.
361 citations
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TL;DR: The HIV-infected patients with gastrointestinal symptoms show low-grade small bowel atrophy and a maturational defect in enterocytes, which may be caused exclusively by HIV.
Abstract: Excerpt Study Objective:To determine small intestinal mucosal structure and function in patients with human immunodeficiency virus (HIV) infection. Design:Prospective, consecutive sample study. Set...
361 citations
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TL;DR: The design and content of SeqAn are described, which comprises implementations of existing, practical state-of-the-art algorithmic components to provide a sound basis for algorithm testing and development and greatly simplifies the rapid development of new bioinformatics tools.
Abstract: Background
The use of novel algorithmic techniques is pivotal to many important problems in life science. For example the sequencing of the human genome [1] would not have been possible without advanced assembly algorithms. However, owing to the high speed of technological progress and the urgent need for bioinformatics tools, there is a widening gap between state-of-the-art algorithmic techniques and the actual algorithmic components of tools that are in widespread use.
361 citations
Authors
Showing all 35717 results
Name | H-index | Papers | Citations |
---|---|---|---|
Andreas Pfeiffer | 149 | 1756 | 131080 |
Nicholas A. Peppas | 141 | 825 | 90533 |
Robert H. Purcell | 139 | 666 | 70366 |
Andrea Castro | 132 | 1500 | 90019 |
Klaus Ley | 129 | 495 | 57964 |
Klaus-Robert Müller | 129 | 764 | 79391 |
Britton Chance | 128 | 1112 | 76591 |
Stefan H. E. Kaufmann | 126 | 925 | 58891 |
Thomas F. Tedder | 123 | 426 | 48374 |
Aravinda Chakravarti | 120 | 451 | 99632 |
Jerome Ritz | 120 | 644 | 47987 |
Thomas C. Quinn | 120 | 827 | 65881 |
Angela D. Friederici | 120 | 701 | 50191 |
E. K. U. Gross | 119 | 1154 | 75970 |
Alexander Rich | 115 | 539 | 50171 |