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Background: Simultaneous pancreas kidney transplantation (SPK), pancreas transplantation alone (PTA) or pancreas transplantation after kidney (PAK) are the only curative treatment options for patients with type 1 (juvenile) diabetes mellitus with or without impaired renal function. Unfortunately, transplant waiting lists for this indication are increasing because the current organ acceptability criteria are restrictive; morbidity and mortality significantly increase with time on the waitlist. Currently, only pancreas organs from donors younger than 50 years of age and with a body mass index (BMI) less than 30 are allocated for transplantation in the Eurotransplant (ET) area. To address this issue we designed a study to increase the available donor pool for these patients.
Methods/Design: This study is a prospective, multicenter (20 German centers), single blinded, non-randomized, two armed trial comparing outcome after SPK, PTA or PAK between organs with the currently allowed donor criteria versus selected organs from donors with extended criteria. Extended donor criteria are defined as organs procured from donors with a BMI of 30 to 34 or a donor age between 50 and 60 years. Immunosuppression is generally standardized using induction therapy with Myfortic, tacrolimus and low dose steroids. In principle, all patients on the waitlist for primary SPK, PTA or PAK are eligible for the clinical trial when they consent to possibly receiving an extended donor criteria organ. Patients receiving an organ meeting the current standard criteria for pancreas allocation (control arm) are compared to those receiving extended criteria organ (study arm); patients are blinded for a follow-up period of one year. The combined primary endpoint is survival of the pancreas allograft and pancreas allograft function after three months, as an early relevant outcome parameter for pancreas transplantation.
Discussion: The EXPAND Study has been initiated to investigate the hypothesis that locally allocated extended criteria organs can be transplanted with similar results compared to the currently allowed standard ET organ allocation. If our study shows a favorable comparison to standard organ allocation criteria, the morbidity and mortality for patients waiting for transplantation could be reduced in the future.
Trial registered at: NCT01384006
The differential charged jet cross sections, jet fragmentation distributions, and jet shapes are measured in minimum bias proton-proton collisions at centre-of-mass energy s√=7 TeV using the ALICE detector at the LHC. Jets are reconstructed from charged particle momenta in the mid-rapidity region using the sequential recombination kT and anti-kT as well as the SISCone jet finding algorithms with several resolution parameters in the range R=0.2 to 0.6. Differential jet production cross sections measured with the three jet finders are in agreement in the transverse momentum (pT) interval 20<pjet,chT<100 GeV/c. They are also consistent with prior measurements carried out at the LHC by the ATLAS collaboration. The jet charged particle multiplicity rises monotonically with increasing jet pT, in qualitative agreement with prior observations at lower energies. The transverse profiles of leading jets are investigated using radial momentum density distributions as well as distributions of the average radius containing 80% (⟨R80⟩) of the reconstructed jet pT. The fragmentation of leading jets with R=0.4 using scaled pT spectra of the jet constituents is studied. The measurements are compared to model calculations from event generators (PYTHIA, PHOJET, HERWIG). The measured radial density distributions and ⟨R80⟩ distributions are well described by the PYTHIA model (tune Perugia-2011). The fragmentation distributions are better described by HERWIG.
Erratum for: Cyclic AMP induces transactivation of the receptors for epidermal growth factor and nerve growth factor, thereby modulating activation of MAP kinase, Akt, and neurite outgrowth in PC12 cells.Journal of biological chemistry, 2002 Nov 15;277(46):43623-30. doi: 10.1074/jbc.M203926200. Epub 2002 Sep 5.
The ALICE collaboration at the LHC reports measurement of the inclusive production cross section of electrons from semi-leptonic decays of beauty hadrons with rapidity |y|<0.8 and transverse momentum 1<pT<10 GeV/c, in pp collisions at s√= 2.76 TeV. Electrons not originating from semi-electronic decay of beauty hadrons are suppressed using the impact parameter of the corresponding tracks. The production cross section of beauty decay electrons is compared to the result obtained with an alternative method which uses the distribution of the azimuthal angle between heavy-flavour decay electrons and charged hadrons. Perturbative QCD calculations agree with the measured cross section within the experimental and theoretical uncertainties. The integrated visible cross section, σb→e=3.47±0.40(stat)+1.12−1.33(sys)±0.07(norm)μb, was extrapolated to full phase space using Fixed Order plus Next-to-Leading Log (FONLL) predictions to obtain the total bb¯ production cross section, σbb¯=130±15.1(stat)+42.1−49.8(sys)+3.4−3.1(extr)±2.5(norm)±4.4(BR)μb.
The ALICE collaboration at the LHC reports measurement of the inclusive production cross section of electrons from semi-leptonic decays of beauty hadrons with rapidity |y|<0.8 and transverse momentum 1<pT<10 GeV/c, in pp collisions at s√= 2.76 TeV. Electrons not originating from semi-electronic decay of beauty hadrons are suppressed using the impact parameter of the corresponding tracks. The production cross section of beauty decay electrons is compared to the result obtained with an alternative method which uses the distribution of the azimuthal angle between heavy-flavour decay electrons and charged hadrons. Perturbative QCD calculations agree with the measured cross section within the experimental and theoretical uncertainties. The integrated visible cross section, σb→e=3.47±0.40(stat)+1.12−1.33(sys)±0.07(norm)μb, was extrapolated to full phase space using Fixed Order plus Next-to-Leading Log (FONLL) predictions to obtain the total bb¯ production cross section, σbb¯=130±15.1(stat)+42.1−49.8(sys)+3.4−3.1(extr)±2.5(norm)±4.4(BR)μb.
CXCR4 chemokine receptor mediates prostate tumor cell adhesion through alpha5 and beta3 integrins
(2006)
The mechanisms leading to prostate cancer metastasis are not understood completely. Although there is evidence that the CXC chemokine receptor (CXCR) 4 and its ligand CXCL12 may regulate tumor dissemination, their role in prostate cancer is controversial. We examined CXCR4 expression and functionality, and explored CXCL12-triggered adhesion of prostate tumor cells to human endothelium or to extracellular matrix proteins laminin, collagen, and fibronectin. Although little CXCR4 was expressed on LNCaP and DU-145 prostate tumor cells, CXCR4 was still active, enabling the cells to migrate toward a CXCL12 gradient. CXCL12 induced elevated adhesion to the endothelial cell monolayer and to immobilized fibronectin, laminin, and collagen. Anti-CXCR4 antibodies or CXCR4 knock out significantly impaired CXCL12-triggered tumor cell binding. The effects observed did not depend on CXCR4 surface expression level. Rather, CXCR4-mediated adhesion was established by alpha5 and beta3 integrin subunits and took place in the presence of reduced p38 and p38 phosphorylation. These data show that chemoattractive mechanisms are involved in adhesion processes of prostate cancer cells, and that binding of CXCL12 to its receptor leads to enhanced expression of alpha5 and beta3 integrins. The findings provide a link between chemokine receptor expression and integrin-triggered tumor dissemination.
In PC12 cells, a well studied model for neuronal differentiation, an elevation in the intracellular cAMP level increases cell survival, stimulates neurite outgrowth, and causes activation of extracellular signal-regulated protein kinase 1 and 2 (ERK1/2). Here we show that an increase in the intracellular cAMP concentration induces tyrosine phosphorylation of two receptor tyrosine kinases, i.e. the epidermal growth factor (EGF) receptor and the high affinity receptor for nerve growth factor (NGF), also termed Trk(A). cAMP-induced tyrosine phosphorylation of the EGF receptor is rapid and correlates with ERK1/2 activation. It occurs also in Panc-1, but not in human mesangial cells. cAMP-induced tyrosine phosphorylation of the NGF receptor is slower and correlates with Akt activation. Inhibition of EGF receptor tyrosine phosphorylation, but not of the NGF receptor, reduces cAMP-induced neurite outgrowth. Expression of dominant-negative Akt does not abolish cAMP-induced survival in serum-free media, but increases cAMP-induced ERK1/2 activation and neurite outgrowth. Together, our results demonstrate that cAMP induces dual signaling in PC12 cells: transactivation of the EGF receptor triggering the ERK1/2 pathway and neurite outgrowth; and transactivation of the NGF receptor promoting Akt activation and thereby modulating ERK1/2 activation and neurite outgrowth.
Erratum in: Correction: Cyclic AMP induces transactivation of the receptors for epidermal growth factor and nerve growth factor, thereby modulating activation of MAP kinase, Akt, and neurite outgrowth in PC12 cells. Journal of biological chemistry 2020 Oct 23;295(43):14792. doi: 10.1074/jbc.AAC120.016177.
The first measurement of two-pion Bose–Einstein correlations in central Pb–Pb collisions at √sNN=2.76 TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.
Inclusive transverse momentum spectra of primary charged particles in Pb–Pb collisions at √sNN=2.76 TeV have been measured by the ALICE Collaboration at the LHC. The data are presented for central and peripheral collisions, corresponding to 0–5% and 70–80% of the hadronic Pb–Pb cross section. The measured charged particle spectra in |η|<0.8 and 0.3<pT<20 GeV/c are compared to the expectation in pp collisions at the same sNN, scaled by the number of underlying nucleon–nucleon collisions. The comparison is expressed in terms of the nuclear modification factor RAA. The result indicates only weak medium effects (RAA≈0.7) in peripheral collisions. In central collisions, RAA reaches a minimum of about 0.14 at pT=6–7 GeV/c and increases significantly at larger pT. The measured suppression of high-pT particles is stronger than that observed at lower collision energies, indicating that a very dense medium is formed in central Pb–Pb collisions at the LHC.
The inclusive charged particle transverse momentum distribution is measured in proton–proton collisions at s=900 GeV at the LHC using the ALICE detector. The measurement is performed in the central pseudorapidity region (|η|<0.8) over the transverse momentum range 0.15<pT<10 GeV/c. The correlation between transverse momentum and particle multiplicity is also studied. Results are presented for inelastic (INEL) and non-single-diffractive (NSD) events. The average transverse momentum for |η|<0.8 is 〈pT〉INEL=0.483±0.001 (stat.)±0.007 (syst.) GeV/c and 〈pT〉NSD=0.489±0.001 (stat.)±0.007 (syst.) GeV/c, respectively. The data exhibit a slightly larger 〈pT〉 than measurements in wider pseudorapidity intervals. The results are compared to simulations with the Monte Carlo event generators PYTHIA and PHOJET.
Rapidity and transverse momentum dependence of inclusive J/ψ production in pp collisions at √s=7 TeV
(2011)
The ALICE experiment at the LHC has studied inclusive J/ψ production at central and forward rapidities in pp collisions at √s=7 TeV. In this Letter, we report on the first results obtained detecting the J/ψ through the dilepton decay into e+e− and μ+μ− pairs in the rapidity ranges |y|<0.9 and 2.5<y<4, respectively, and with acceptance down to zero pT. In the dielectron channel the analysis was carried out on a data sample corresponding to an integrated luminosity Lint=5.6 nb−1 and the number of signal events is NJ/ψ=352±32(stat.)±28(syst.); the corresponding figures in the dimuon channel are Lint=15.6 nb−1 and NJ/ψ=1924±77(stat.)±144(syst.). The measured production cross sections are σJ/ψ(|y|<0.9)=10.7±1.0(stat.)±1.6(syst.)−2.3+1.6(syst.pol.)μb and σJ/ψ(2.5<y<4)=6.31±0.25(stat.)±0.76(syst.)−1.96+0.95(syst.pol.)μb. The differential cross sections, in transverse momentum and rapidity, of the J/ψ were also measured.
Two-particle angular correlations between unidentified charged trigger and associated particles are measured by the ALICE detector in p–Pb collisions at a nucleon–nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum range 0.7 < pT,assoc < pT,trig < 5.0 GeV/c is examined, to include correlations induced by jets originating from low momentum-transfer scatterings (minijets). The correlations expressed as associated yield per trigger particle are obtained in the pseudorapidity range |η| < 0.9. The near-side long-range pseudorapidity correlations observed in high-multiplicity p–Pb collisions are subtracted from both near-side short-range and away-side correlations in order to remove the non-jet-like components. The yields in the jet-like peaks are found to be invariant with event multiplicity with the exception of events with low multiplicity. This invariance is consistent with the particles being produced via the incoherent fragmentation of multiple parton–parton scatterings, while the yield related to the previously observed ridge structures is not jet-related. The number of uncorrelated sources of particle production is found to increase linearly with multiplicity, suggesting no saturation of the number of multi-parton interactions even in the highest multiplicity p–Pb collisions. Further, the number scales only in the intermediate multiplicity region with the number of binary nucleon–nucleon collisions estimated with a Glauber Monte-Carlo simulation.
The extinction of conditioned fear depends on an efficient interplay between the amygdala and the medial prefrontal cortex (mPFC). In rats, high-frequency electrical mPFC stimulation has been shown to improve extinction by means of a reduction of amygdala activity. However, so far it is unclear whether stimulation of homologues regions in humans might have similar beneficial effects. Healthy volunteers received one session of either active or sham repetitive transcranial magnetic stimulation (rTMS) covering the mPFC while undergoing a 2-day fear conditioning and extinction paradigm. Repetitive TMS was applied offline after fear acquisition in which one of two faces (CS+ but not CS−) was associated with an aversive scream (UCS). Immediate extinction learning (day 1) and extinction recall (day 2) were conducted without UCS delivery. Conditioned responses (CR) were assessed in a multimodal approach using fear-potentiated startle (FPS), skin conductance responses (SCR), functional near-infrared spectroscopy (fNIRS), and self-report scales. Consistent with the hypothesis of a modulated processing of conditioned fear after high-frequency rTMS, the active group showed a reduced CS+/CS− discrimination during extinction learning as evident in FPS as well as in SCR and arousal ratings. FPS responses to CS+ further showed a linear decrement throughout both extinction sessions. This study describes the first experimental approach of influencing conditioned fear by using rTMS and can thus be a basis for future studies investigating a complementation of mPFC stimulation to cognitive behavioral therapy (CBT).
Rezensionen [2021]
(2021)
Verzeichnis
Einzelrezensionen
146 Benner, Julia/Schneider-Kempf, Barbara/Putjenter, Sigrun (Hg.): Schauplatz der Künste – Bild und Text im Kinderbuch. Festgabe
für Carola Pohlmann zum 60. Geburtstag (Claudia Blei-Hoch)
147 Conrad, Maren (Hg.): Moderne Märchen. Populäre Variationen in jugendkulturellen Literatur- und Medienformaten der Gegenwart (Ernst Seibert)
149 Dettmar, Ute/Roeder, Caroline/Tomkowiak, Ingrid (Hg.): Schnittstellen der Kinder- und Jugendmedienforschung. Aktuelle Positionen und Perspektiven (Nicola König)
151 Dettmar, Ute/Pecher, Claudia Maria/Anker, Martin (Hg.): Bilder zu»Klassikern« (Annette Kliewer)
152 Ewers, Hans-Heino (Hg.): Michael Ende. Zur Aktualität eines Klassikers von internationalem Rang (Thomas Boyken)
154 Frickel, Daniela A. /Kagelmann, Andre/Seidler, Andreas /Glasenapp, Gabriele von (Hg.): Kinder- und Jugendmedien im inklusiven Blick. Analytische und didaktische Perspektiven (Susanne Blumesberger)
156 Gansel, Carsten/Ächtler, Norman/KümmerlingMeibauer, Bettina (Hg.): Erzählen über Kindheit und Jugend in der Gegenwartsliteratur (Nadine Bieker)
158 Giuriato, Davide: Grenzenlose Bestimmbarkeit. Kindheiten in der Literatur der Moderne (Julia Boog-Kaminski)
160 Hodkinson, Owen/ Lovatt, Helen (Hg.): Classical Reception and Children’s Literature. Greece, Rome and Childhood Transformation
(Ludger Scherer)
162 Jantzen, Christoph/Ritter, Alexandra/Ritter, Michel (Hg.): Faszination Zauberwelt. Neue Perspektiven auf die Fantastik in Kinder- und Jugendmedien (Ernst Seibert)
164 Josting, Petra/Kruse, Iris (Hg.): Karen-Susan Fessel. Bielefelder Poet in Residence 2018 (Kirsten Kumschlies)
165 Kalbermatten, Manuela: »The match that lights the fire«. Gesellschaft und Geschlecht in Future-Fiction für Jugendliche (Sabine Planka)
167 Kurwinkel, Tobias /Norrick-Rühl, Corinna/ Schmerheim, Philipp (Hg.): Die Welt im Bild erfassen. Multidisziplinäre Perspektiven auf
das Bilderbuch (Sonja Müller-Carstens)
169 Kurwinkel, Tobias /Schmerheim, Philipp (Hg.): Handbuch Kinder- und Jugendliteratur. Unter Mitarbeit von Stefanie Jakobi
(Thomas Boyken)
171 Lexe, Heidi (Hg.): Time Warp und Taschenuhr. Zeit in der Kinder- und Jugendliteratur (Inger Lison)
173 Lötscher, Christine: Die Alice-Maschine. Figurationen der Unruhe in der Populärkultur (Astrid Henning-Mohr)
175 Marciniak, Katarzyna (Hg.): Chasing Mythical Beasts. The Reception of Ancient Monsters in Children’s and Young Adults’ Culture (Thomas Kullmann)
177 Oetken, Mareile/Vach, Karin/Weinkauff, Gina (Hg.): Klaus Ensikat, Stefanie Harjes, Susanne Janssen. Heidelberger Kinderliteraturgespräche 2017/18 (Heinz-Jürgen und Ursula Kliewer)
179 Schäfer, Iris (Hg.): Zur Ästhetik psychischer Krankheiten in kinder- und jugendliterarischen Medien. Psychoanalytische und tiefenpsychologische Analysen – transdisziplinär erweitert (Kirsten Kumschlies)
180 Stemmann, Anna: Räume der Adoleszenz. Deutschsprachige Jugendliteratur der Gegenwart in topographischer Perspektive (Sabine Planka)
Sammelrezensionen
182 Pugh, Tison: Harry Potter and Beyond. On J. K. Rowling’s Fantasies and Other Fictions Jarazo-Álvarez, Rubén/Alderete-Diez, Pilar (Hg.): Cultural Politics in Harry Potter. Life, Death and the Politics of Fear (Thomas Hardtke)
185 Clermont, Philippe/Henky, Danièle (Hg.):Transmédialités du conte Freeman, Matthew/Rampazzo Gambarato, Renira (Hg.): The Routledge Companion to Transmedia Studies (Ludger Scherer)
Der Erfolg einer nationalen Forschungsdateninfrastruktur hängt von der Einbindung der gesamten Wissenschaftsgemeinschaft und -infrastruktur ab. In zahlreichen Bundesländern existieren Landesinitiativen für Forschungsdatenmanagement oder ähnliche Einrichtungen, die dazu beitragen können, diese Einbindung zu erreichen. Das gemeinsame Papier von Vertretern aus verschiedenen Bundesländern argumentiert, dass eine enge Verknüpfung der Landesinitiativen mit dem NFDI e.V. erfolgen sollte, um die Potentiale der Zusammenarbeit zu nutzen.
Der NFDI e. V. wird einen bedeutsamen Beitrag für einen besseren Umgang mit Forschungsdaten leisten, doch der Erfolg der nationalen Forschungsdateninfrastruktur ist letztlich von einer Einbindung der gesamten Wissenschaftsgemeinschaft und -infrastruktur abhängig. Die vielfältigen Forschungseinrichtungen einzubinden, erfordert Koordination auf vielen Ebenen. Speziell Hochschulen haben eine tragende Rolle für sowohl disziplinäre und interdisziplinäre Forschung als auch wissenschaftliche Ausbildung in Deutschland und sind damit zentrale Akteure für die fachübergreifende Forschungsdateninfrastruktur. Durch die Förderung von Kooperationen und Koordination auf Ebene von Ländern oder Länderverbünden lässt sich die Entwicklung der nationalen Forschungsdateninfrastruktur unterstützen. Landesinitiativen für Forschungsdatenmanagement (FDM) oder ähnliche koordinierende Einrichtungen können die digitale Transformation in der Forschung durch Information, den Aufbau von Kooperationen und die Qualifikation von Personal unterstützen. Ihre Einrichtung, dauerhafte Etablierung und Einbeziehung in die Arbeit des NFDI e. V. ist ein wichtiger Beitrag zur Schaffung einer nationalen Forschungsdateninfrastruktur.
Freeze-out radii extracted from three-pion cumulants in pp, p–Pb and Pb–Pb collisions at the LHC
(2014)
In high-energy collisions, the spatio-temporal size of the particle production region can be measured using the Bose–Einstein correlations of identical bosons at low relative momentum. The source radii are typically extracted using two-pion correlations, and characterize the system at the last stage of interaction, called kinetic freeze-out. In low-multiplicity collisions, unlike in high-multiplicity collisions, two-pion correlations are substantially altered by background correlations, e.g. mini-jets. Such correlations can be suppressed using three-pion cumulant correlations. We present the first measurements of the size of the system at freeze-out extracted from three-pion cumulant correlations in pp, p–Pb and Pb–Pb collisions at the LHC with ALICE. At similar multiplicity, the invariant radii extracted in p–Pb collisions are found to be 5–15% larger than those in pp, while those in Pb–Pb are 35–55% larger than those in p–Pb. Our measurements disfavor models which incorporate substantially stronger collective expansion in p–Pb as compared to pp collisions at similar multiplicity.
We report on the measurement of the inclusive Υ (1S) production in Pb–Pb collisions at √sNN = 2.76 TeV carried out at forward rapidity (2.5 < y < 4) and down to zero transverse momentum using its μ+μ−decay channel with the ALICE detector at the Large Hadron Collider. A strong suppression of the inclusive Υ (1S) yield is observed with respect to pp collisions scaled by the number of independent nucleon–nucleon collisions. The nuclear modification factor, for events in the 0–90% centrality range, amounts to 0.30 ± 0.05(stat) ± 0.04(syst). The observed Υ (1S) suppression tends to increase with the centrality of the collision and seems more pronounced than in corresponding mid-rapidity measurements. Our results are compared with model calculations, which are found to underestimate the measured suppression and fail to reproduce its rapidity dependence.
Genetic code expansion facilitates position‐selective labeling of rna for biophysical studies
(2019)
Nature relies on reading and synthesizing the genetic code with high fidelity. Nucleic acid building blocks that are orthogonal to the canonical A‐T and G‐C base‐pairs are therefore uniquely suitable to facilitate position‐specific labeling of nucleic acids. Here, we employ the orthogonal kappa‐xanthosine‐base‐pair for in vitro transcription of labeled RNA. We devised an improved synthetic route to obtain the phosphoramidite of the deoxy‐version of the kappa nucleoside in solid phase synthesis. From this DNA template, we demonstrate the reliable incorporation of xanthosine during in vitro transcription. Using NMR spectroscopy, we show that xanthosine introduces only minor structural changes in an RNA helix. We furthermore synthesized a clickable 7‐deaza‐xanthosine, which allows to site‐specifically modify transcribed RNA molecules with fluorophores or other labels.
Introduction: We aimed at dissociating the neural correlates of memory disorders in Alzheimer’s disease (AD) and frontotemporal lobar degeneration (FTLD).
Methods: We included patients with AD (n = 19, 11 female, mean age 61 years) and FTLD (n = 11, 5 female, mean age 61 years) in early stages of their diseases. Memory performance was assessed by means of verbal and visual memory subtests from the Wechsler Memory Scale (WMS-R), including forgetting rates. Brain glucose utilization was measured by [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) and brain atrophy by voxel-based morphometry (VBM) of T1-weighted magnetic resonance imaging (MRI) scans. Using a whole brain approach, correlations between test performance and imaging data were computed separately in each dementia group, including a group of control subjects (n = 13, 6 female, mean age 54 years) in both analyses. The three groups did not differ with respect to education and gender.
Results: Patients in both dementia groups generally performed worse than controls, but AD and FTLD patients did not differ from each other in any of the test parameters. However, memory performance was associated with different brain regions in the patient groups, with respect to both hypometabolism and atrophy: Whereas in AD patients test performance was mainly correlated with changes in the parieto-mesial cortex, performance in FTLD patients was correlated with changes in frontal cortical as well as subcortical regions. There were practically no overlapping regions associated with memory disorders in AD and FTLD as revealed by a conjunction analysis.
Conclusion: Memory test performance may not distinguish between both dementia syndromes. In clinical practice, this may lead to misdiagnosis of FTLD patients with poor memory performance. Nevertheless, memory problems are associated with almost completely different neural correlates in both dementia syndromes. Obviously, memory functions are carried out by distributed networks which break down in brain degeneration.