Experimental Limitations Using Reprogrammed Cells for Hematopoietic Differentiation

We review here our experiences with the in vitro reprogramming of somatic cells to induced pluripotent stem cells (iPSC) and subsequent in vitro development of hematopoietic cells from these iPSC and from embryonic stem cells (ESC). While, in principle, the in vitro reprogramming and subsequent differentiation can generate hematopoietic cell from any somatic cells, it is evident that many of the steps in this process need to be significantly improved before it can be applied to human cells and used in clinical settings of hematopoietic stem cell (HSC) transplantations

Lateral Flow Test zur Abstoßungsdiagnostik mittels Antikörper

Nierentransplantationen gehören zu den häufigsten Transplantationen weltweit. Nierentrans-plantatempfänger unterziehen sich regelmäßigen Untersuchungen, u. a. um eine Nierenabsto-ßung frühzeitig festzustellen. Für die Diagnose wird oft der Anstieg des Serum-Kreatinin-Werts zum Anlass für die Durchführung einer Transplantatbiopsie genommen, sie gilt als diagnostischer Goldstandard für Abstoßung. Die Biopsie ist allerdings aufwändig, schmerzhaft und mit möglichen Komplikationen (Blutung, Infektionsrisiko) verbunden. Der Serum-Kreatinin-Anstieg zeigt häufig auch unspezifisch andere Transplantatstörungen an. Daher werden Alternativen zur spezifischen Früherkennung der Nierentransplantatabstoßung gesucht. Dabei eignet sich der Nachweis spezifischer, immunologisch bedeutsamer Biomarker, die bei einer Abstoßung vom Körper produziert werden. Deren Analyse könnte als Point-of-Care-Test eine schnelle, hoch sensitive sowie schmerz- und nebenwirkungsfreie Möglichkeit der Abstoßungs-diagnostik bieten. Ein Lateral Flow Assay (LFA) bietet sich hier als Testplattform an, die inner-halb von Minuten nachweist, ob der Biomarker z. B. im Urin vorliegt. In dieser Arbeit wurden die Biomarker C-reaktives Protein (CRP), der lösliche Interleukin-2-Rezeptor (sIL-2Rα, auch sCD25) und CXCL9 (auch MIG, Monokine induced by Gamma-Interferon) ausgewählt. Durch mehrere Biomarkerstudien wurden die Biomarker sCD25 und CXCL9 mittels Mann-Whitney-U-Test als signifikant erhöht während verschiedener Formen einer Nierenabstoßung identifiziert. CRP zählt zu den Akute-Phase-Proteinen und dient zur Ab-grenzung einer allgemeinen Entzündungsreaktion. Für das Chemokin CXCL9 wurden Antikörper generiert und mittels Enzyme-linked Immunoabsorbent Assay validiert, für CRP und sCD25 kommerziell erhältliche Antikörper verwendet. Vor der LFA-Entwicklung wurden Microarrays als Modell verwendet, um zunächst die Bindungseigenschaften der Antikörper zu untersuchen. Zur Visualisierung des Testergebnisses auf dem LFA wurden mittels Flokkulationstest Konjugate aus Goldnanopartikeln und Antikörpern untersucht. Anschließend wurde für jeden Biomarker ein LFA aufgebaut, optimiert und etabliert. Die Validierung der etablierten LFAs zur Detektion von sCD25 und CXCL9 fanden anhand von Urin- und Plasmaproben von Nierentransplantat-Empfängern, deren Diagnose nach BANFF-Kriterien erstellt wurde, statt. Somit konnte für den sCD25-LFA eine Sensitivität von 87,5 % und eine Spezifität von 84,6 % erreicht werden. Bei Verwendung der geschätzten glomerulären Filtrationsrate auf Basis des Serum-Kreatinin-Wertes am Tag der Transplantatbiopsie zur Diagnosestellung einer Abstoßung wurde nur eine Sensitivität von 85 % bei einer Spezifität von 30,8 % erzielt. Der LFA zur Detektion von CXCL9 zeigte eine Sensitivität von 53 % und eine Spezifität von 71 % auf

Konzeptionierung einer lösbaren Zellkontaktierung für Akku-Packs zur Erhöhung der Demontage- und Recyclingfreundlichkeit

Die Verwendung von Batteriesystemen im Mobilitätssektor ist ein wichtiger Faktor zur Reduzierung von Treibhausgasemissionen und somit für den Schutz der Umwelt. Allerdings ist die Demontage, die Wiederverwendung und das Recycling der Akkus derzeit noch eine Herausforderung. Batteriezellen werden in der Regel durch Schweißverbindungen kontaktiert. Dies macht es unmöglich, einzelne Zellen aus dem Pack zerstörungsfrei zu entfernen. Bisher gibt es bereits Kenntnisse über die Eigenschaften von lösbaren elektrischen Kontakten. Es gibt jedoch noch keine Ansätze, die eine lösbare Kontaktierung ermöglichen, wobei die Herausforderungen bei Batteriepacks mit mehreren Zellen und deren Design berücksichtigt werden. Die Demontage des Packs ist das Hauptproblem im Hinblick auf ein kreislaufwirtschaftskonformes Design. Lösbare Zellkontakte sind hierfür eine mögliche Lösung. Die größte Herausforderung bei der Umsetzung lösbarer Zellkontakte besteht darin, einen möglichst geringen und gleichmäßigen Kontaktwiderstand zu erreichen. Dazu ist ebenfalls ein Verständnis über die Abhängigkeiten zwischen dem Kontaktwiderstand und verschiedenen Einflussfaktoren notwendig. Daher stellen die Autoren eine Analyse relevanter Wechselwirkungen in der lösbaren Kontaktierung von Batteriezellen im Format 18650 vor. Diese umfasst unter anderem eine Untersuchung der Kontaktflächen verschiedener Zellen und die Ermittlung deren Kontaktwiderstände unter Verwendung verschiedener Kontaktpaarungen. Abschließend werden, basierend auf Anforderungen an die Kontaktierung der Zellen, verschiedene Lösungsprinzipien für eine lösbare Kontaktierung definiert und ein initiales Konzept daraus abgeleitet

New method to study ion-molecule reactions at low temperatures and application to the H2+_2^+ + H2_2 →\rightarrow H3+_3^+ + H reaction

Studies of ion-molecule reactions at low temperatures are difficult because stray electric fields in the reaction volume affect the kinetic energy of charged reaction partners. We describe a new experimental approach to study ion-molecule reactions at low temperatures and present, as example, a measurement of the ${\rm H}_2^+ + {\rm H}_2\rightarrow {\rm H}_3^+ + {\rm H}$ reaction with the ${\rm H}_2^+$ ion prepared in a single rovibrational state at collision energies in the range $E_{\rm col}/k_{\rm B} = 5$-60 K. To reach such low collision energies, we use a merged-beam approach and observe the reaction within the orbit of a Rydberg electron, which shields the ions from stray fields. The first beam is a supersonic beam of pure ground-state H$_2$ molecules and the second is a supersonic beam of H$_2$ molecules excited to Rydberg-Stark states of principal quantum number $n$ selected in the range 20-40. Initially, the two beams propagate along axes separated by an angle of 10$^\circ$. To merge the two beams, the Rydberg molecules in the latter beam are deflected using a surface-electrode Rydberg-Stark deflector. The collision energies of the merged beams are determined by measuring the velocity distributions of the two beams and they are adjusted by changing the temperature of the pulsed valve used to generate the ground-state ${\rm H}_2$ beam and by adapting the electric-potential functions to the electrodes of the deflector. The collision energy is varied down to below $E_{\rm col}/k_{\rm B}= 10$ K, i.e., below $E_{\rm col}\approx 1$ meV, with an energy resolution of 100 $\mu$eV. We demonstrate that the Rydberg electron acts as a spectator and does not affect the cross sections, which are found to closely follow a classical-Langevin-capture model in the collision-energy range investigated. Because all neutral atoms and molecules can be excited to Rydberg states, this method of studyingComment: 39 pages, 10 figure

TNF-related apoptosis-inducing ligand, interferon gamma-induced protein 10, and C-reactive protein in predicting the progression of SARS-CoV-2 infection : a prospective cohort study

Background: Early prognostication of COVID-19 severity will potentially improve patient care. Biomarkers, such as TNF-related apoptosis-inducing ligand (TRAIL), interferon gamma-induced protein 10 (IP-10), and C-reactive protein (CRP), might represent possible tools for point-of-care testing and severity prediction. Methods: In this prospective cohort study, we analyzed serum levels of TRAIL, IP-10, and CRP in patients with COVID-19, compared them with control subjects, and investigated the association with disease sever ity. Results: A total of 899 measurements were performed in 132 patients (mean age 64 years, 40.2% females). Among patients with COVID-19, TRAIL levels were lower (49.5 vs 87 pg/ml, P = 0.0142), whereas IP-10 and CRP showed higher levels (667.5 vs 127 pg/ml, P <0.001; 75.3 vs 1.6 mg/l, P <0.001) than healthy controls. TRAIL yielded an inverse correlation with length of hospital and intensive care unit (ICU) stay, Simplified Acute Physiology Score II, and National Early Warning Score, and IP-10 showed a positive cor relation with disease severity. Multivariable regression revealed that obesity (adjusted odds ratio [aOR] 5.434, 95% confidence interval [CI] 1.005-29.38), CRP (aOR 1.014, 95% CI 1.002-1.027), and peak IP-10 (aOR 1.001, 95% CI 1.00-1.002) were independent predictors of in-ICU mortality

Promising results of a clinical feasibility study: CIRBP as a potential biomarker in pediatric cardiac surgery

ObjectiveCold-inducible RNA binding Protein (CIRBP) has been shown to be a potent inflammatory mediator and could serve as a novel biomarker for inflammation. Systemic inflammatory response syndrome (SIRS) and capillary leak syndrome (CLS) are frequent complications after pediatric cardiac surgery increasing morbidity, therefore early diagnosis and therapy is crucial. As CIRBP serum levels have not been analyzed in a pediatric population, we conducted a clinical feasibility establishing a customized magnetic bead panel analyzing CIRBP in pediatric patients undergoing cardiac surgery.MethodsA prospective hypothesis generating observational clinical study was conducted at the German Heart Center Berlin during a period of 9 months starting in May 2020 (DRKS00020885, https://drks.de/search/de/trial/DRKS00020885). Serum samples were obtained before the cardiac operation, upon arrival at the pediatric intensive care unit, 6 and 24 h after the operation in patients up to 18 years of age with congenital heart disease (CHD). Customized multiplex magnetic bead-based immunoassay panels were developed to analyze CIRBP, Interleukin-1β (IL-1β), Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-10 (IL-10), Monocyte chemotactic protein 1 (MCP-1), Syndecan-1 (SDC-1), Thrombomodulin (TM), Vascular endothelial growth factor (VEGF-A), Angiopoietin-2 (Ang-2), and Fibroblast growth factor 23 (FGF-23) in 25 µl serum using the Luminex MagPix® system.Results19 patients representing a broad range of CHD (10 male patients, median age 2 years, 9 female patients, median age 3 years) were included in the feasibility study. CIRBP was detectable in the whole patient cohort. Relative to individual baseline values, CIRBP concentrations increased 6 h after operation and returned to baseline levels over time. IL-6, IL-8, IL-10, and MCP-1 concentrations were significantly increased after operation and except for MCP-1 concentrations stayed upregulated over time. SDC-1, TM, Ang-2, as well as FGF-23 concentrations were also significantly increased, whereas VEGF-A concentration was significantly decreased after surgery.DiscussionUsing customized magnetic bead panels, we were able to detect CIRBP in a minimal serum volume (25 µl) in all enrolled patients. To our knowledge this is the first clinical study to assess CIRBP serum concentrations in a pediatric population

Illuminating hydrological processes at the soil-vegetation-atmosphere interface with water stable isotopes

Funded by DFG research project “From Catchments as Organised Systems to Models based on Functional Units” (FOR 1Peer reviewedPublisher PDFPublisher PD

Association of Polyaminergic Loci With Anxiety, Mood Disorders, and Attempted Suicide

The polyamine system has been implicated in a number of psychiatric conditions, which display both alterations in polyamine levels and altered expression of genes related to polyamine metabolism. Studies have identified associations between genetic variants in spermidine/spermine N1-acetyltransferase (SAT1) and both anxiety and suicide, and several polymorphisms appear to play important roles in determining gene expression.We genotyped 63 polymorphisms, spread across four polyaminergic genes (SAT1, spermine synthase (SMS), spermine oxidase (SMOX), and ornithine aminotransferase like-1 (OATL1)), in 1255 French-Canadian individuals who have been followed longitudinally for 22 years. We assessed univariate associations with anxiety, mood disorders, and attempted suicide, as assessed during early adulthood. We also investigated the involvement of gene-environment interactions in terms of childhood abuse, and assessed internalizing and externalizing symptoms as endophenotypes mediating these interactions. Overall, each gene was associated with at least one main outcome: anxiety (SAT1, SMS), mood disorders (SAT1, SMOX), and suicide attempts (SAT1, OATL1). Several SAT1 polymorphisms displayed disease-specific risk alleles, and polymorphisms in this gene were involved in gene-gene interactions with SMS to confer risk for anxiety disorders, as well as gene-environment interactions between childhood physical abuse and mood disorders. Externalizing behaviors demonstrated significant mediation with regards to the association between OATL1 and attempted suicide, however there was no evidence that externalizing or internalizing behaviors were appropriate endophenotypes to explain the associations with mood or anxiety disorders. Finally, childhood sexual abuse did not demonstrate mediating influences on any of our outcomes.These results demonstrate that genetic variants in polyaminergic genes are associated with psychiatric conditions, each of which involves a set of separate and distinct risk alleles. As several of these polymorphisms are associated with gene expression, these findings may provide mechanisms to explain the alterations in polyamine metabolism which have been observed in psychiatric disorders

Genetic correlations and genome-wide associations of cortical structure in general population samples of 22824 adults

Cortical thickness, surface area and volumes vary with age and cognitive function, and in neurological and psychiatric diseases. Here we report heritability, genetic correlations and genome-wide associations of these cortical measures across the whole cortex, and in 34 anatomically predefined regions. Our discovery sample comprises 22,824 individuals from 20 cohorts within the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium and the UK Biobank. We identify genetic heterogeneity between cortical measures and brain regions, and 160 genome-wide significant associations pointing to wnt/β-catenin, TGF-β and sonic hedgehog pathways. There is enrichment for genes involved in anthropometric traits, hindbrain development, vascular and neurodegenerative disease and psychiatric conditions. These data are a rich resource for studies of the biological mechanisms behind cortical development and aging