89 results on '"Hartmann L"'
Search Results
2. Implementierung von Teilhabeangeboten des Bayerischen Demenzfonds - eine Analyse von förderlichen und hinderlichen Faktoren
- Author
-
Ihnken, A, Schnabel, EL, Fischer, K, Hartmann, L, Schwendner, C, Ihnken, A, Schnabel, EL, Fischer, K, Hartmann, L, and Schwendner, C
- Published
- 2023
3. Simulationspersonen schützen - aber wie?
- Author
-
Strohmer, R, Beilharz, S, Hartmann, L, Strohmer, R, Beilharz, S, and Hartmann, L
- Published
- 2023
4. Der Monogenes zwischen Aqeda und Athena : Zu Semantik und Kontext eines einzigartigen Christusprädikats
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Frey, Jörg, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), and Frey, Jörg
- Published
- 2023
5. Platon von Gericht : der oberste Gerichtshof der Vereinigten Staaten von Amerika und Platon
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Walser, Andreas Victor, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), and Walser, Andreas Victor
- Published
- 2023
6. Heilsgeschehen im Arbeitszimmer: «Verkündigung an Maria» (Zürich, Kunsthaus ca. 1455) und die Bibliothek des Zürcher Chorherren Felix Hemmerli (1388–1458)
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Eigler, Ulrich, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), and Eigler, Ulrich
- Published
- 2023
7. Antworten der Gesprächspartner: ein vernachlässigter Schlüssel zum Verständnis in Platons Werk
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), and Hartmann, L ( Lucius )
- Published
- 2023
8. 'Heres fiduciarius' in Grabinschriften revisited
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Babusiaux, Ulrike; https://orcid.org/0000-0002-9464-0273, Xandry, Thamar, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Babusiaux, Ulrike; https://orcid.org/0000-0002-9464-0273, and Xandry, Thamar
- Published
- 2023
9. Ratio und similitudo: die vernunftkonforme Argumentation im Dialogus des Petrus Alfonsi
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Cardelle de Hartmann, Carmen; https://orcid.org/0000-0002-5251-050X, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), and Cardelle de Hartmann, Carmen; https://orcid.org/0000-0002-5251-050X
- Abstract
Anders als in religionspolemischen Werken früherer Autoren, die auf die exegetische Diskussion zentriert sind, argumentiert Petrus Alfonsi in seinem Dialogus (um 1110 verfasst) gleichermaßen auf der Grundlage von auctoritas (der Bibel) und von ratio. In diesem Beitrag wird diskutiert, wie Petrus Alfonsi die vernunftbasierte Argumentation begrifflich fasst und umsetzt. An einer Stelle präzisiert Petrus Alfonsi drei Quellen der rationalen Erkenntnis. Die Aussage wird anhand einer genauen Lektüre und durch die Heranziehung der Quelle, das Werk des jüdischen Philosophen Saadia Gaon, Emunoth we-Deoth, interpretiert. Petrus Alfonsi unterscheidet darin die spontane Erkenntnis durch die Sinne, die deduktive Argumentation auf der Grundlage von allgemein anerkannten Prämissen (necessariae rationes) und die similitudo, die sich als die evidenzbasierte Argumentation verstehen lässt. Im Dialogus argumentiert Petrus Alfonsi nur selten auf der Grundlage von Prämissen, immer wieder findet sich eine Argumentation, die auf beobachtbaren Phänomenen basiert. Häufig legt Petrus Erkenntnisse der Naturphilosophie dar, die er durch Naturbespiele erläutert. Für dieses Verfahren setzt er auch den Begriff similitudo ein.
- Published
- 2023
10. Benutzt Cassiodor in den Institutiones das Preceptum Canonis Ptolomei oder Ptolemaios’ Handliche Tafeln?
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Zingg, Emanuel, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), and Zingg, Emanuel
- Abstract
Die anonyme astronomische Schrift Preceptum Canonis Ptolomei wurde 534/5 vielleicht in Rom verfasst und gilt als eine Quelle des Kapitels zur Astronomie in Cassiodors nur wenig jüngeren Institutiones, in denen der berühmte Staats-mann eine Art Literaturkanon vorstellt. Eine genauere Betrachtung führt jedoch zum Schluss, dass Cassiodor das Preceptum nicht heranzog. Von Ptolemaios’ astronomischen Schriften scheint er nur die Procheiroi kanones eingesehen zu haben, mit deren griechischem Text er jedoch sehr unbeholfen umgeht. Wir vermuten daher, Cassiodor habe das ihm von der Materie her fremde Werk nicht selber konsultiert, sondern diese Aufgabe an eine Hilfskraft delegiert.
- Published
- 2023
11. Referential Features and Verbal Agreement with Neuter Plural Subjects in Ancient Greek
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Sommer, Florian; https://orcid.org/0000-0002-6166-2281, Widmer, Paul; https://orcid.org/0000-0002-9949-5212, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Sommer, Florian; https://orcid.org/0000-0002-6166-2281, and Widmer, Paul; https://orcid.org/0000-0002-9949-5212
- Published
- 2023
12. Epistemologisches in Thukydides 2.54.2–3
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Martin, Gunther; https://orcid.org/0000-0003-4368-4249, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), and Martin, Gunther; https://orcid.org/0000-0003-4368-4249
- Published
- 2023
13. Virtute vero gubernante rem publicam: Der virtus-Begriff als Funktion politischer Systeme
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Beer, Beate, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), and Beer, Beate
- Published
- 2023
14. Catheter ablation of atrial arrhythmias by using a multipolar grid-patterned high density mapping catheter in patients with congenital heart disease: a single-center experience
- Author
-
Kerst, G, primary, Gulgun, M, additional, Ozcan, S, additional, Ostenmayer, S, additional, Hartmann, L, additional, Hanten, J, additional, and Vazquez-Jimenez, J, additional
- Published
- 2022
- Full Text
- View/download PDF
15. Philosophen im Legionslager von Argentorate?: Überlegungen zum Wanddekor mit Ritzinschriften in den Offiziersquartieren
- Author
-
Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), Kolb, Anne; https://orcid.org/0009-0004-4776-2421, Semenzato, Camille, Hartmann, Lucius; https://orcid.org/0000-0003-0397-9528, Semenzato, C ( Camille ), Hartmann, L ( Lucius ), and Kolb, Anne; https://orcid.org/0009-0004-4776-2421
- Published
- 2022
16. Hematopoietic Stem/Progenitor Cells and Engineering: FROM HARMFUL TO USEFUL: EXPLOITING A LEUKEMIC TRANSCRIPTION FACTOR FOR LARGE-SCALE EX VIVO MANUFACTURE OF HUMAN MACROPHAGES
- Author
-
Windisch, R., primary, Soliman, S., additional, Hoffmann, A., additional, Chen-Wichmann, L., additional, Lutz, S., additional, Kellner, C., additional, Redondo-Monte, E., additional, Vosberg, S., additional, Hartmann, L., additional, Schneider, S., additional, Beier, F., additional, Strobl, C., additional, Weigert, O., additional, Peipp, M., additional, Schuendeln, M., additional, Bernhagen, J., additional, Humpe, A., additional, Brendel, C., additional, Klump, H., additional, Greif, P., additional, and Wichmann, C., additional
- Published
- 2022
- Full Text
- View/download PDF
17. FROM HARMFUL TO USEFUL: EXPLOITING A LEUKEMIC TRANSCRIPTION FACTOR FOR LARGE-SCALE EX VIVO MANUFACTURE OF HUMAN MACROPHAGES
- Author
-
Windisch, R., Soliman, S., Hoffmann, A., Chen-Wichmann, L., Lutz, S., Kellner, C., Redondo-Monte, E., Vosberg, S., Hartmann, L., Schneider, S., Beier, F., Strobl, C., Weigert, O., Peipp, M., Schündeln, Michael, Bernhagen, J., Humpe, A., Brendel, C., Klump, H., Greif, P., and Wichmann, C.
- Subjects
Medizin ,ComputingMethodologies_GENERAL - Abstract
Poster Abstract
- Published
- 2022
18. ��Das Provinzial-Recht des F��rstenthums Eichsfeld
- Author
-
Hartmann, L.
- Published
- 2022
- Full Text
- View/download PDF
19. Bewertung putativer BRCA1/BRCA2-Spleißmutationen hinsichtlich einer genetische Prädisposition für Brust- und Eierstockkrebs
- Author
-
Honisch, E, Theiss, S, Hartmann, L, Betz, B, Schaal, H, and Niederacher, D
- Published
- 2024
- Full Text
- View/download PDF
20. Implications of the Thermal Stability of FEC-Based Electrolytes for Li-Ion Batteries
- Author
-
Teufl, Tobias, Pritzl, Daniel, Hartmann, L., Solchenbach, Sophie, Mendez, Manuel A., and Gasteiger, Hubert A.
- Abstract
Fluoroethylene-carbonate (FEC) is a common co-solvent for high-voltage cathodes and for silicon-based anodes in lithium-ion batteries. However, FEC has a limited thermal stability when used with LiPF6as conductive salt, and its decomposition can trigger detrimental side reactions. Here, we will examine the reaction mechanism of FEC with LiPF6, confirming that vinylene-carbonate (VC) and HF are produced at elevated temperatures. By full-cell cycling at 45 °C in a T-cell setup with a micro-reference electrode (μ-RE), we can show by electrochemical impedance spectroscopy that these side reactions not only lead to an impedance increase of the anode and the cathode, but also trigger transition metal dissolution. By comparison of FEC and ethylene-carbonate (EC) as cyclic carbonate, we demonstrate that FEC has no advantage at high-voltage operation compared to EC, when employing cathode materials or cathode potentials for which no lattice oxygen is evolved. Finally, we use multi-layer pouch-cells to analyze the gassing of an EC- and FEC-based electrolyte upon extended charge/discharge cycling at 45 °C, showing that the latter leads to cell bulging upon extended charge/discharge cycling at 45 °C due to the oxidation of the VC formed by the thermal decomposition of FEC above ≈4.4 − 4.5 V vs. Li+/Li.
- Published
- 2023
- Full Text
- View/download PDF
21. 404 - Hematopoietic Stem/Progenitor Cells and Engineering: FROM HARMFUL TO USEFUL: EXPLOITING A LEUKEMIC TRANSCRIPTION FACTOR FOR LARGE-SCALE EX VIVO MANUFACTURE OF HUMAN MACROPHAGES.
- Author
-
Windisch, R., Soliman, S., Hoffmann, A., Chen-Wichmann, L., Lutz, S., Kellner, C., Redondo-Monte, E., Vosberg, S., Hartmann, L., Schneider, S., Beier, F., Strobl, C., Weigert, O., Peipp, M., Schuendeln, M., Bernhagen, J., Humpe, A., Brendel, C., Klump, H., and Greif, P.
- Subjects
- *
PROGENITOR cells , *TRANSCRIPTION factors , *MACROPHAGES , *ENGINEERING , *HUMAN beings - Published
- 2022
- Full Text
- View/download PDF
22. Identification of TAK-756, A Potent TAK1 Inhibitor for the Treatment of Osteoarthritis through Intra-Articular Administration.
- Author
-
Langlois JB, Brenneisen S, Rodde S, Vangrevelinghe E, Rose G, Lerch P, Sorge M, Ullrich T, Patora-Komisarska K, Quancard J, Larger P, Gianola L, Textor C, Chenal G, Rubic-Schneider T, Simkova K, Masmanidou O, Scheufler C, Lammens A, Bouzan A, Demirci S, Flotte L, Rivet H, Hartmann L, Guezel D, Flueckiger M, Schilb A, Schuepbach E, Kettle R, Jacobi C, Pearson D, Richards PJ, and Minetti GC
- Abstract
Osteoarthritis (OA) is a chronic and degenerative joint disease affecting more than 500 million patients worldwide with no disease-modifying treatment approved to date. Several publications report on the transforming growth factor β-activated kinase 1 (TAK1) as a potential molecular target for OA, with complementary anti-catabolic and anti-inflammatory effects. We report herein on the development of TAK1 inhibitors with physicochemical properties suitable for intra-articular injection, with the aim to achieve high drug concentration at the affected joint, while avoiding severe toxicity associated with systemic inhibition. More specifically, reducing solubility by increasing crystallinity, while maintaining moderate lipophilicity proved to be a good compromise to ensure high and sustained free drug exposures in the joint. Furthermore, structure-based design allowed for an improvement of selectivity versus interleukin-1 receptor-associated kinases 1 and 4 (IRAK1/4). Finally, TAK-756 was discovered as a potent TAK1 inhibitor with good selectivity versus IRAK1/4 as well as excellent intra-articular pharmacokinetic properties.
- Published
- 2024
- Full Text
- View/download PDF
23. Psychosocial Interventions for Preventing Mental Health Conditions in Adolescents With Emotional Problems: A Meta-Analysis.
- Author
-
Du Toit S, Tomlinson M, Laurenzi CA, Gordon S, Hartmann L, Abrahams N, Bradshaw M, Brand A, Melendez-Torres GJ, Servili C, Dua T, Ross DA, Lai J, and Skeen S
- Abstract
Mental health conditions constitute a major burden of disease for adolescents globally and can lead to significant adverse consequences. This systematic review aimed to identify if psychosocial interventions are effective in preventing mental health conditions in adolescents already experiencing emotional problems. We searched for randomized controlled trials comparing psychosocial interventions for preventing mental health conditions with care as usual in adolescents aged 10-19 who are experiencing symptoms of emotional problems. We searched PubMed/Medline, PsycINFO, ERIC, EMBASE, and ASSIA databases to identify studies. We found 82 eligible studies (n = 13,562 participants). Findings show that interventions can reduce mental health conditions and increase positive mental health. Across all reported time points, psychosocial interventions showed significant, small-to moderate-sized beneficial effects on preventing mental health conditions (SMD: -0.26, 95% CI [-0.42, -0.19] and small positive effects on positive mental health (SMD: 0.17, 95% CI [0.097, 0.29]. There were no statistically significant pooled findings suggesting that psychosocial interventions had either a positive or negative effect on self-harm or suicide; aggressive, disruptive and oppositional behavior; substance use; or school attendance. Despite the positive findings, a critical gap exists in the design of effective psychosocial interventions to reduce self-harm and suicide, and other risk behaviors in adolescents with symptoms of emotional problems., (Copyright © 2024 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
24. Transcriptional regulators ensuring specific gene expression and decision-making at high TGFβ doses.
- Author
-
Hartmann L, Kristofori P, Li C, Becker K, Hexemer L, Bohn S, Lenhardt S, Weiss S, Voss B, Loewer A, and Legewie S
- Subjects
- Humans, Transcription Factors metabolism, Transcription Factors genetics, Epithelial Cells metabolism, Smad Proteins metabolism, Female, Animals, Transforming Growth Factor beta metabolism, Epithelial-Mesenchymal Transition genetics, Gene Expression Regulation, Signal Transduction genetics
- Abstract
TGFβ-signaling regulates cancer progression by controlling cell division, migration, and death. These outcomes are mediated by gene expression changes, but the mechanisms of decision-making toward specific fates remain unclear. Here, we combine SMAD transcription factor imaging, genome-wide RNA sequencing, and morphological assays to quantitatively link signaling, gene expression, and fate decisions in mammary epithelial cells. Fitting genome-wide kinetic models to our time-resolved data, we find that most of the TGFβ target genes can be explained as direct targets of SMAD transcription factors, whereas the remainder show signs of complex regulation, involving delayed regulation and strong amplification at high TGFβ doses. Knockdown experiments followed by global RNA sequencing revealed transcription factors interacting with SMADs in feedforward loops to control delayed and dose-discriminating target genes, thereby reinforcing the specific epithelial-to-mesenchymal transition at high TGFβ doses. We identified early repressors, preventing premature activation, and a late activator, boosting gene expression responses for a sufficiently strong TGFβ stimulus. Taken together, we present a global view of TGFβ-dependent gene regulation and describe specificity mechanisms reinforcing cellular decision-making., (© 2024 Hartmann et al.)
- Published
- 2024
- Full Text
- View/download PDF
25. MicroRNAs modulate SARS-CoV-2 infection of primary human hepatocytes by regulating the entry factors ACE2 and TMPRSS2.
- Author
-
Khanal R, Heinen N, Bogomolova A, Meister TL, Herrmann ST, Westhoven S, Nocke MK, Todt D, Jockenhövel F, Klein IM, Hartmann L, Vondran FWR, Steinmann E, Zimmer G, Ott M, Brown RJP, Sharma AD, and Pfaender S
- Subjects
- Humans, Virus Internalization, Male, Female, Middle Aged, Pandemics, Betacoronavirus, Coronavirus Infections metabolism, Coronavirus Infections virology, Coronavirus Infections genetics, Cells, Cultured, Pneumonia, Viral virology, Pneumonia, Viral genetics, Pneumonia, Viral metabolism, Aged, RNA, Viral, Serine Endopeptidases metabolism, Serine Endopeptidases genetics, Angiotensin-Converting Enzyme 2 metabolism, Angiotensin-Converting Enzyme 2 genetics, COVID-19 genetics, Hepatocytes virology, Hepatocytes metabolism, SARS-CoV-2, MicroRNAs metabolism, MicroRNAs genetics
- Abstract
Background and Aims: Severe acute respiratory syndrome coronavirus (SARS-CoV-2) preferentially infects the respiratory tract; however, several studies have implicated a multi-organ involvement. Hepatic dysfunctions caused by SARS-CoV-2 infection have been increasingly recognized and described to correlate with disease severity. To elucidate molecular factors that could contribute towards hepatic infection, we concentrated on microRNAs (miRNAs), a class of small non-coding RNAs that modulate various cellular processes and which are reported to be differentially regulated during liver injury. We aimed to study the infection of primary human hepatocytes (PHH) with SARS-CoV-2 and to evaluate the potential of miRNAs for modulating viral infection., Methods: We analysed liver autopsies from a coronavirus disease 19 (COVID-19)-positive cohort for the presence of viral RNA using Nanopore sequencing. PHH were used for the infection with SARS-CoV-2. The candidate miRNAs targeting angiotensin converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) were identified using in silico approaches. To discover the potential regulatory mechanism, transfection experiments, qRT-PCRs, western blots and luciferase reporter assays were performed., Results: We could detect SARS-CoV-2 RNA in COVID-19-positive liver autopsies. We show that PHH express ACE2 and TMPRSS2 and can be readily infected with SARS-CoV-2, resulting in robust replication. Transfection of selected miRNA mimics reduced SARS-CoV-2 receptor expression and SARS-CoV-2 burden in PHH. In silico and biochemical analyses supported a potential direct binding of miR-141-3p to the SARS-CoV-2 genome., Conclusion: We confirm that PHH are susceptible to SARS-CoV-2 infection and demonstrate selected miRNAs targeting SARS-CoV-2 entry factors and/or the viral genome reduce viral loads. These data provide novel insights into hepatic susceptibility to SARS-CoV-2 and associated dysfunctions in COVID-19., (© 2024 The Author(s). Liver International published by John Wiley & Sons Ltd.)
- Published
- 2024
- Full Text
- View/download PDF
26. Selective Glycan Presentation in Liquid-Ordered or -Disordered Membrane Phases and its Effect on Lectin Binding.
- Author
-
Blawitzki LC, Monzel C, Schmidt S, and Hartmann L
- Abstract
Glycan-protein interactions play a key role in various biological processes from fertilization to infections. Many of these interactions take place at the glycocalyx-a heavily glycosylated layer at the cell surface. Despite its significance, studying the glycocalyx remains challenging due to its complex, dynamic, and heterogeneous nature. This study introduces a glycocalyx model allowing for the first time to control spatial organization and heterogeneity of the glycan moieties. Glycan-mimetics with lipid-moieties that partition into either liquid-ordered (Lo, lipid rafts) or liquid-disordered (Ld) phases of giant unilamellar vesicles (GUVs), which serve as simplified cell membrane models mimicking lipid rafts, are developed. This phase-specific allocation allows controlled placement of glycan motifs in distinct membrane environments, creating heteromultivalent systems that replicate the natural glycocalyx's complexity. We show that phase localization of glycan mimetics significantly influences recruitment of protein receptors to the membrane. Glycan-conjugates in the ordered phase demonstrate enhanced lectin binding, supporting the idea that raft-like domains facilitate stronger receptor interactions. This study provides a platform for systematically investigating spatial and dynamic presentation of glycans in biological systems and presents the first experimental evidence that glycan accumulation in lipid rafts enhances receptor binding affinity, offering deeper insights into the glycocalyx's functional mechanisms., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
- Published
- 2024
- Full Text
- View/download PDF
27. Synthesis of Dual-Responsive Amphiphilic Glycomacromolecules: Controlled Release of Glycan Ligands via pH and UV Stimuli.
- Author
-
Jäck N, Hemming A, and Hartmann L
- Subjects
- Ligands, Hydrogen-Ion Concentration, Surface-Active Agents chemistry, Surface-Active Agents chemical synthesis, Molecular Structure, Delayed-Action Preparations chemistry, Ultraviolet Rays, Polysaccharides chemistry, Micelles
- Abstract
This work presents a versatile strategy for the synthesis of dual stimuli-responsive amphiphilic glycomacromolecules with tailored release properties. Amphiphilic precision glycomacromolecules (APGs) derived from tailor-made building blocks using solid phase polymer synthesis form glycofunctionalized micelles, a versatile class of materials with applications in drug delivery, as antiinfection agents as well as simple cell mimetics. In this work, this concept is extended by integrating cleavable building blocks into APGs now allowing stimuli-responsive release of glycan ligands or destruction of the micelles. This study incorporates a newly designed acid-labile building block, 4-(4-(((((9H-fluoren-9-yl)methoxy)carbonyl)amino)methyl)-1,3-dioxolan-2-yl)benzoic acid (DBA), suitable also for other types of solid phase or amide chemistry, and an established UV-cleavable 2-nitrobenzyl linker (PL). The results demonstrate that both linkers can be cleaved independently and thus allow dual stimuli-responsive release from the APG micelles. By choosing the APG design e.g., placing the cleavable linkers between glycomacromolecular blocks presenting different types of carbohydrates, they can tune APG and micellar stability as well as the interaction and cluster formation with a carbohydrate-recognizing lectin. Such dual-responsive glycofunctionalized micelles have wide potential for use in drug delivery applications or for the development as anti-adhesion agents in antiviral and antibacterial treatments., (© 2024 The Author(s). Macromolecular Rapid Communications published by Wiley‐VCH GmbH.)
- Published
- 2024
- Full Text
- View/download PDF
28. Thiol-selective native grafting from polymerization for the generation of protein-polymer conjugates.
- Author
-
Feldhof MI, Sperzel S, Bonda L, Boye S, Braunschweig AB, Gerling-Driessen UIM, and Hartmann L
- Abstract
Protein-polymer conjugates combine properties of biopolymers and synthetic polymers, such as specific bioactivity and increased stability, with great benefits for various applications from catalysis to biomedicine. Furthermore, polymer conjugation can mimic important posttranslational modifications of proteins such as glycosylation. There are typically two approaches to create protein-polymer conjugates: the protein is functionalized in advance with an initiator for a grafting-from method or a previously produced polymer is conjugated to the protein via a grafting-to method. In this study, we present a new approach that uses native proteins and allows for direct grafting-from using a thiol-induced, light-activated controlled radical polymerization (TIRP) that is initiated at thiols from specific cysteine residues of the protein. This straightforward method is employed to introduce polymers onto proteins and enzymes without any prior protein modifications, it works in aqueous buffer and maintains the protein's native structure and activity. The resulting protein-polymer conjugates exhibit high molar masses and low dispersities. We demonstrate the versatility of this approach by introducing different types of polymers such as hydrophilic poly(2-hydroxyethyl acrylate) (pHEAA), temperature-responsive poly( N -isopropylacrylamide) (pNIPAM) as well as glycopolymers mimicking the natural protein glycosylation and enabling selective interactions. We present successful combinations of the protein and polymer functions e.g. , temperature-induced aggregation leading to an increase in enzyme activity and the introduction of artificial glycosylation inducing specific protein-protein cluster formation and giving straightforward access to glycosurfaces. Based on this straightforward, potentially scalable yet highly controlled synthesis of protein-polymer conjugates, various areas of applications are envisioned ranging from biomedicine to material sciences., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2024
- Full Text
- View/download PDF
29. Macromolecular tool box to elucidate CLAVATA3/EMBRYO SURROUNDING REGION-RELATED-RLK binding, signaling, and downstream effects.
- Author
-
Narasimhan M, Jahnke N, Kallert F, Bahafid E, Böhmer F, Hartmann L, and Simon R
- Subjects
- Protein Serine-Threonine Kinases metabolism, Protein Binding, Peptides metabolism, Arabidopsis Proteins metabolism, Arabidopsis Proteins genetics, Arabidopsis metabolism, Signal Transduction
- Abstract
Plant peptides communicate by binding to a large family of receptor-like kinases (RLKs), and they share a conserved binding mechanism, which may account for their promiscuous interaction with several RLKs. In order to understand the in vivo binding specificity of the CLAVATA3/EMBRYO SURROUNDING REGION-RELATED peptide family in Arabidopsis, we have developed a novel set of CLAVATA3 (CLV3)-based peptide tools. After carefully evaluating the CLE peptide binding characteristics, using solid phase synthesis process, we modified the CLV3 peptide and attached a fluorophore and a photoactivable side group. We observed that the labeled CLV3 shows binding specificity within the CLAVATA1 clade of RLKs while avoiding the distantly related PEP RECEPTOR clade, thus resolving the contradictory results obtained previously by many in vitro methods. Furthermore, we observed that the RLK-bound CLV3 undergoes clathrin-mediated endocytosis and is trafficked to the vacuole via ARA7 (a Rab GTPase)-labeled endosomes. Additionally, modifying CLV3 for light-controlled activation enabled spatial and temporal control over CLE signaling. Hence, our CLV3 macromolecular toolbox can be used to study rapid cell specific down-stream effects. Given the conserved binding properties, in the future our toolbox can also be used as a template to modify other CLE peptides., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Experimental Biology.)
- Published
- 2024
- Full Text
- View/download PDF
30. Glycomacromolecules to Tailor Crowded and Heteromultivalent Glycocalyx Mimetics.
- Author
-
Blawitzki LC, Bartels N, Bonda L, Schmidt S, Monzel C, and Hartmann L
- Subjects
- Unilamellar Liposomes chemistry, Biomimetic Materials chemistry, Polymerization, Polymers chemistry, Glycocalyx chemistry, Glycocalyx metabolism
- Abstract
The glycocalyx, a complex carbohydrate layer on cell surfaces, plays a crucial role in various biological processes. Understanding native glycocalyces' complexity is challenging due to their intricate and dynamic nature. Simplified mimics of native glycocalyces offer insights into glycocalyx functions but often lack molecular precision and fail to replicate key features of the natural analogues like molecular crowding and heteromultivalency. We introduce membrane-anchoring precision glycomacromolecules synthesized via solid-phase polymer synthesis (SPPoS) and thiol-induced, light-activated controlled radical polymerization (TIRP), enabling the construction of crowded and heteromultivalent glycocalyx mimetics with varying molecular weights and densities in giant unilamellar vesicles (GUVs). The incorporation and dynamics of glycomacromolecules in the GUVs are examined via microscopy and fluorescence correlation spectroscopy (FCS) and studies on lectin-carbohydrate-mediated adhesion of GUVs reveal inhibitory and promotional adhesion effects corresponding to different glycocalyx mimetic compositions, bridging the gap between synthetic models and native analogues.
- Published
- 2024
- Full Text
- View/download PDF
31. "It is in the Nature of Men": The Normalization of Non-Consensual Sex and Intimate Partner Violence Against Women with Acquired Physical Disabilities in South Africa.
- Author
-
Hunt X, van der Merwe A, Swartz L, Xakayi W, Chideya Y, Hartmann L, Botha M, and Hamilton A
- Subjects
- Humans, Female, South Africa, Adult, Cross-Sectional Studies, Male, Middle Aged, Sex Offenses psychology, Sex Offenses statistics & numerical data, Risk Factors, Social Stigma, Interpersonal Relations, Sexual Behavior psychology, Intimate Partner Violence psychology, Intimate Partner Violence statistics & numerical data, Disabled Persons psychology, Disabled Persons statistics & numerical data, Sexual Partners psychology, Qualitative Research
- Abstract
This study employed a cross-sectional, qualitative individual interview methodology to explore South African women with physical disabilities' experiences of intimate partner and sexual violence, inclusive of non-consensual and coerced sexual intercourse. For the participants, disability was a factor that intersected with gender norms to create vulnerability to abuse, and that patriarchal ideologies constructing how women should perform their gendered roles in marriage or sexual partnerships, as well as disability stigma, exacerbated this vulnerability. It is important to develop understandings of the different risk factors for violence - at the individual level and in the context of dyadic relationships - to develop programming to better support women., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2024
- Full Text
- View/download PDF
32. Neonatal Exhaled Breath Sampling for Infrared Spectroscopy: Biomarker Analysis.
- Author
-
Feddahi N, Hartmann L, Felderhoff-Müser U, Roy S, Lampe R, and Maiti KS
- Abstract
Monitoring health conditions in neonates for early therapeutic intervention in case deviations from physiological conditions is crucial for their long-term development. Due to their immaturity preterm born neonates are dependent on particularly careful physical and neurological diagnostic methods. Ideally, these should be noninvasive, noncontact, and radiation free. Infrared spectroscopy was used to analyze exhaled breath from 71 neonates with a special emphasis on preterm infants, as a noninvasive, noncontact, and radiation-free diagnostic tool. Passive sample collection was performed by skilled clinicians. Depending on the mode of respiratory support of infants, four different sampling procedures were adapted to collect exhaled breath. With the aid of appropriate reference samples, infrared spectroscopy has successfully demonstrated its effectiveness in the analysis of breath samples of neonates. The discernible increase in concentrations of carbon dioxide, carbon monoxide, and methane in collected samples compared to reference samples served as compelling evidence of the presence of exhaled breath. With regard to technical hurdles and sample analysis, samples collected from neonates without respiratory support proved to be more advantageous compared to those obtained from intubated infants and those with CPAP (continuous positive airway pressure). The main obstacle lies in the significant dilution of exhaled breath in the case of neonates receiving respiratory support. Metabolic analysis of breath samples holds promise for the development of noninvasive biomarker-based diagnostics for both preterm and sick neonates provided an adequate amount of breath is collected., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)
- Published
- 2024
- Full Text
- View/download PDF
33. Engineering an inducible leukemia-associated fusion protein enables large-scale ex vivo production of functional human phagocytes.
- Author
-
Windisch R, Soliman S, Hoffmann A, Chen-Wichmann L, Danese A, Vosberg S, Bravo J, Lutz S, Kellner C, Fischer A, Gebhard C, Redondo Monte E, Hartmann L, Schneider S, Beier F, Strobl CD, Weigert O, Peipp M, Schündeln M, Stricker SH, Rehli M, Bernhagen J, Humpe A, Klump H, Brendel C, Krause DS, Greif PA, and Wichmann C
- Subjects
- Humans, Hematopoietic Stem Cells metabolism, Oncogene Proteins, Fusion genetics, Oncogene Proteins, Fusion metabolism, Recombinant Fusion Proteins metabolism, Recombinant Fusion Proteins genetics, Myeloid-Lymphoid Leukemia Protein metabolism, Myeloid-Lymphoid Leukemia Protein genetics, Leukemia genetics, Leukemia pathology, Leukemia metabolism, Protein Engineering methods, Phagocytosis, Phagocytes metabolism, Cell Differentiation
- Abstract
Ex vivo expansion of human CD34+ hematopoietic stem and progenitor cells remains a challenge due to rapid differentiation after detachment from the bone marrow niche. In this study, we assessed the capacity of an inducible fusion protein to enable sustained ex vivo proliferation of hematopoietic precursors and their capacity to differentiate into functional phagocytes. We fused the coding sequences of an FK506-Binding Protein 12 (FKBP12)-derived destabilization domain (DD) to the myeloid/lymphoid lineage leukemia/eleven nineteen leukemia (MLL-ENL) fusion gene to generate the fusion protein DD-MLL-ENL and retrovirally expressed the protein switch in human CD34+ progenitors. Using Shield1, a chemical inhibitor of DD fusion protein degradation, we established large-scale and long-term expansion of late monocytic precursors. Upon Shield1 removal, the cells lost self-renewal capacity and spontaneously differentiated, even after 2.5 y of continuous ex vivo expansion. In the absence of Shield1, stimulation with IFN-γ, LPS, and GM-CSF triggered terminal differentiation. Gene expression analysis of the obtained phagocytes revealed marked similarity with naïve monocytes. In functional assays, the novel phagocytes migrated toward CCL2, attached to VCAM-1 under shear stress, produced reactive oxygen species, and engulfed bacterial particles, cellular particles, and apoptotic cells. Finally, we demonstrated Fcγ receptor recognition and phagocytosis of opsonized lymphoma cells in an antibody-dependent manner. Overall, we have established an engineered protein that, as a single factor, is useful for large-scale ex vivo production of human phagocytes. Such adjustable proteins have the potential to be applied as molecular tools to produce functional immune cells for experimental cell-based approaches., Competing Interests: Competing interests statement:The authors declare no competing interest.
- Published
- 2024
- Full Text
- View/download PDF
34. Sweet Janus Particles: Multifunctional Inhibitors of Carbohydrate-Based Bacterial Adhesion.
- Author
-
Üclü S, Marschelke C, Drees F, Giesler M, Wilms D, Köhler T, Schmidt S, Synytska A, and Hartmann L
- Subjects
- Humans, Escherichia coli chemistry, Carbohydrates chemistry, Temperature, Bacterial Adhesion, Multifunctional Nanoparticles
- Abstract
Escherichia coli and other bacteria use adhesion receptors, such as FimH, to attach to carbohydrates on the cell surface as the first step of colonization and infection. Efficient inhibitors that block these interactions for infection treatment are multivalent carbohydrate-functionalized scaffolds. However, these multivalent systems often lead to the formation of large clusters of bacteria, which may pose problems for clearing bacteria from the infected site. Here, we present Man-containing Janus particles (JPs) decorated on one side with glycomacromolecules to target Man-specific adhesion receptors of E. coli . On the other side, poly( N -isopropylacrylamide) is attached to the particle hemisphere, providing temperature-dependent sterical shielding against binding and cluster formation. While homogeneously functionalized particles cluster with multiple bacteria to form large aggregates, glycofunctionalized JPs are able to form aggregates only with individual bacteria. The formation of large aggregates from the JP-decorated single bacteria can still be induced in a second step by increasing the temperature and making use of the collapse of the PNIPAM hemisphere. This is the first time that carbohydrate-functionalized JPs have been derived and used as inhibitors of bacterial adhesion. Furthermore, the developed JPs offer well-controlled single bacterial inhibition in combination with cluster formation upon an external stimulus, which is not achievable with conventional carbohydrate-functionalized particles.
- Published
- 2024
- Full Text
- View/download PDF
35. GalNAc- or Mannose-PEG-Functionalized Polyplexes Enable Effective Lectin-Mediated DNA Delivery.
- Author
-
Steffens RC, Folda P, Fendler NL, Höhn M, Bücher-Schossau K, Kempter S, Snyder NL, Hartmann L, Wagner E, and Berger S
- Subjects
- Azides, DNA metabolism, Transfection, Polyethylene Glycols, Mannose
- Abstract
A cationic, dendrimer-like oligo(aminoamide) carrier with four-arm topology based on succinoyl tetraethylene pentamine and histidines, cysteines, and N -terminal azido-lysines was screened for plasmid DNA delivery on various cell lines. The incorporated azides allow modification with various shielding agents of different polyethylene glycol (PEG) lengths and/or different ligands by copper-free click reaction, either before or after polyplex formation. Prefunctionalization was found to be advantageous over postfunctionalization in terms of nanoparticle formation, stability, and efficacy. A length of 24 ethylene oxide repetition units and prefunctionalization of ≥50% of azides per carrier promoted optimal polyplex shielding. PEG shielding resulted in drastically reduced DNA transfer, which could be successfully restored by active lectin targeting via novel GalNAc or mannose ligands, enabling enhanced receptor-mediated endocytosis of the carrier system. The involvement of the asialoglycoprotein receptor (ASGPR) in the uptake of GalNAc-functionalized polyplexes was confirmed in the ASGPR-positive hepatocarcinoma cell lines HepG2 and Huh7. Mannose-modified polyplexes showed superior cellular uptake and transfection efficacy compared to unmodified and shielded polyplexes in mannose-receptor-expressing dendritic cell-like DC2.4 cells.
- Published
- 2024
- Full Text
- View/download PDF
36. Development of an advanced multiwavelength emission detector for the analytical ultracentrifuge.
- Author
-
Lautenbach V, Onishchukov G, Wawra SE, Frank U, Hartmann L, Peukert W, and Walter J
- Abstract
An advanced design of the analytical ultracentrifuge with multiwavelength emission detection (MWE-AUC) is presented which offers outstanding performance concerning the spectral resolution and range flexibility as well as the quality of the data acquired. The excitation by a 520 nm laser is complemented with a 405 nm laser. An external spectrograph with three switchable tunable gratings permits optimisation of the spectral resolution in an order of magnitude range while keeping the spectral region broad. The new system design leads also to a significant reduction of systematic signal noise and allows the assessment and control of inner filter effects. Details regarding the very large signal dynamic range are presented, an important aspect when studying samples in a broad concentration range of up to five orders of magnitude. Our system is validated by complementary studies on two biological systems, fluorescent BSA and GFP, using the commercial Optima AUC with absorbance detection for comparison. Finally, we demonstrate the capabilities of our second generation MWE-AUC with respect to multiwavelength characterisation of gold nanoclusters, which exhibit specific fluorescence depending on their structure. Overall, this work depicts an important stepping stone for the concept of multiwavelength emission detection in AUC. The MWE-AUC developed, being to our knowledge the first and sole one of its kind, has reached the development level suitable for the future in-depth studies of size-, shape- and composition-dependent emission properties of colloids., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2024
- Full Text
- View/download PDF
37. Etrolizumab-s fails to control E-Cadherin-dependent co-stimulation of highly activated cytotoxic T cells.
- Author
-
Wiendl M, Dedden M, Liu LJ, Schweda A, Paap EM, Ullrich KA, Hartmann L, Wieser L, Vitali F, Atreya I, Müller TM, Günther C, Atreya R, Neurath MF, and Zundler S
- Subjects
- Humans, Integrins, Cadherins, T-Lymphocytes, Cytotoxic, Inflammatory Bowel Diseases, Antibodies, Monoclonal, Humanized
- Abstract
Despite promising preclinical and earlier clinical data, a recent phase III trial on the anti-β7 integrin antibody etrolizumab in Crohn's disease (CD) did not reach its primary endpoint. The mechanisms leading to this outcome are not well understood. Here we characterize the β7
+ T cell compartment from patients with CD in comparison to cells from individuals without inflammatory bowel disease. By flow cytometric, transcriptomic and functional profiling of circulating T cells, we find that triple-integrin-expressing (α4+ β7+ β1hi ) T cells have the potential to home to the gut despite α4β7 blockade and have a specific cytotoxic signature. A subset of triple-integrin-expressing cells readily acquires αE expression and could be co-stimulated via E-Cadherin-αEβ7 interactions in vitro. Etrolizumab-s fails to block such αEβ7 signalling at high levels of T cell stimulation. Consistently, in CD patients treated with etrolizumab, T cell activation correlates with cytotoxic signatures. Collectively, our findings might add one important piece to the puzzle to explain phase III trial results with etrolizumab, while they also highlight that αEβ7 remains an interesting target for future therapeutic approaches in inflammatory bowel disease., (© 2024. The Author(s).)- Published
- 2024
- Full Text
- View/download PDF
38. Using WhatsApp support groups to promote responsive caregiving, caregiver mental health and child development in the COVID-19 era: A randomised controlled trial of a fully digital parenting intervention.
- Author
-
Skeen S, Marlow M, du Toit S, Melendez-Torres GJ, Mudekunye L, Mapalala E, Ngoma K, Ntanda BM, Maketha M, Grieve C, Hartmann L, Gordon S, and Tomlinson M
- Abstract
Objective: Digital interventions hold important potential for supporting parents when face-to-face interventions are unavailable. We assessed the feasibility and effectiveness of a digital parenting intervention in Zambia and Tanzania., Methods: Using a randomised controlled trial, we evaluated the Sharing Stories digital parenting intervention for caregivers of children aged 9-32 months with access to a smartphone in their household. Caregivers were stratified based on child age and randomly assigned to the intervention or waitlist control arm. The intervention was delivered via facilitated WhatsApp groups over 6 weeks to promote caregiver wellbeing and responsive caregiving through shared reading activities. Primary outcomes were caregiver-reported responsive caregiving, child language and socio-emotional development. Secondary outcomes were caregiver mental health and parental stress. Masked assessors conducted assessments at baseline and immediate follow-up., Results: Between October 2020 and March 2021, we randomly assigned 494 caregiver-child dyads to the intervention ( n = 248) or waitlist control ( n = 246) arm. Caregivers in the intervention group reported more responsive caregiving (OR = 2.55, 95% CI: 1.15-5.66, p = 0.02), time reading or looking at books (β = 0.45, p = 0.04) and telling stories (β = 0.72, p = 0.002). Intervention caregivers reported significantly lower symptoms of depression (β = -0.64, p = 0.05) and anxiety (β = -0.65, p = 0.02). Child development and parental stress did not differ significantly between groups., Conclusions: Digital parenting interventions using WhatsApp can effectively promote responsive caregiving and caregiver mental health in low-resource settings, with great potential for scalability., Trial Registration: ISRCTN database, ISRCTN77689525., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article., (© The Author(s) 2023.)
- Published
- 2023
- Full Text
- View/download PDF
39. Moleculargenetic and in Addition Partly Discrepant Infection Serological Malaria Testing in Two Blood Donors.
- Author
-
Pichl L, Konietzko K, Hartmann L, Puscasu B, and Jiménez Klingberg C
- Abstract
Introduction: According to the guidelines (GL) valid in Germany, persons born or raised in a malaria-endemic area or had continuously stayed in a malaria-endemic area for more than 6 months may only be admitted donating blood if, among other things, validated and quality-assured laboratory diagnostics show that there is no evidence of infectivity. In a statement of the Working Group "Blood" of the Federal Ministry of Health (WGB), a reduction of the deferral period from 4 to 3 years and an antibody test after the deferral period are recommended., Methods: In accordance with the GL, nucleic acid testing (NAT) by means of PCR is carried out at our institution after a retention period of 4 years. In addition to the validated molecular biological testing, an infection serological examination was performed., Case Presentation: In the present cases, Plasmodia genome was detected in the respective single PCR in two blood donors originating from malaria-endemic areas after the expiry of the deferral period. However, one donor tested negative for antibodies against Plasmodia ., Discussion/conclusion: This observation is discussed in the context of a recommendation of the WGB. The question is addressed whether PCR testing is dispensable or whether a combination of infection serological testing and NAT should be favored., Competing Interests: The authors have no conflicts of interest to declare., (© 2023 The Author(s). Published by S. Karger AG, Basel.)
- Published
- 2023
- Full Text
- View/download PDF
40. Facile Synthesis of Catechol-Containing Polyacrylamide Copolymers: Synergistic Effects of Amine, Amide and Catechol Residues in Mussel-Inspired Adhesives.
- Author
-
Bonda L, Müller J, Fischer L, Löwe M, Kedrov A, Schmidt S, and Hartmann L
- Abstract
The straightforward synthesis of polyamide-derived statistical copolymers with catechol, amine, amide and hydroxy residues via free radical polymerization is presented. In particular, catechol, amine and amide residues are present in natural mussel foot proteins, enabling strong underwater adhesion due to synergistic effects where cationic residues displace hydration and ion layers, followed by strong short-rang hydrogen bonding between the catechol or primary amides and SiO
2 surfaces. The present study is aimed at investigating whether such synergistic effects also exist for statistical copolymer systems that lack the sequence-defined positioning of functional groups in mussel foot proteins. A series of copolymers is established and the adsorption in saline solutions on SiO2 is determined by quartz crystal microbalance measurements and ellipsometry. These studies confirm a synergy between cationic amine groups with catechol units and primary amide groups via an increased adsorptivity and increased polymer layer thicknesses. Therefore, the free radical polymerization of catechol, amine and amide monomers as shown here may lead to simplified mussel-inspired adhesives that can be prepared with the readily scalable methods required for large-scale applications.- Published
- 2023
- Full Text
- View/download PDF
41. Potentiating Tweezer Affinity to a Protein Interface with Sequence-Defined Macromolecules on Nanoparticles.
- Author
-
Seiler T, Lennartz A, Klein K, Hommel K, Figueroa Bietti A, Hadrovic I, Kollenda S, Sager J, Beuck C, Chlosta E, Bayer P, Juul-Madsen K, Vorup-Jensen T, Schrader T, Epple M, Knauer SK, and Hartmann L
- Subjects
- Humans, Survivin, HeLa Cells, Inhibitor of Apoptosis Proteins metabolism, Macromolecular Substances metabolism, Active Transport, Cell Nucleus, Cell Nucleus metabolism, Gold, Metal Nanoparticles
- Abstract
Survivin, a well-known member of the inhibitor of apoptosis protein family, is upregulated in many cancer cells, which is associated with resistance to chemotherapy. To circumvent this, inhibitors are currently being developed to interfere with the nuclear export of survivin by targeting its protein-protein interaction (PPI) with the export receptor CRM1. Here, we combine for the first time a supramolecular tweezer motif, sequence-defined macromolecular scaffolds, and ultrasmall Au nanoparticles (us-AuNPs) to tailor a high avidity inhibitor targeting the survivin-CRM1 interaction. A series of biophysical and biochemical experiments, including surface plasmon resonance measurements and their multivalent evaluation by EVILFIT, reveal that for divalent macromolecular constructs with increasing linker distance, the longest linkers show superior affinity, slower dissociation, as well as more efficient PPI inhibition. As a drawback, these macromolecular tweezer conjugates do not enter cells, a critical feature for potential applications. The problem is solved by immobilizing the tweezer conjugates onto us-AuNPs, which enables efficient transport into HeLa cells. On the nanoparticles, the tweezer valency rises from 2 to 16 and produces a 100-fold avidity increase. The hierarchical combination of different scaffolds and controlled multivalent presentation of supramolecular binders was the key to the development of highly efficient survivin-CRM1 competitors. This concept may also be useful for other PPIs.
- Published
- 2023
- Full Text
- View/download PDF
42. CAR NK-92 cell-mediated depletion of residual TCR+ cells for ultrapure allogeneic TCR-deleted CAR T-cell products.
- Author
-
Kath J, Du W, Martini S, Elsallab M, Franke C, Hartmann L, Drosdek V, Glaser V, Stein M, Schmueck-Henneresse M, Reinke P, Volk HD, Abou-El-Enein M, and Wagner DL
- Subjects
- Humans, T-Lymphocytes, Receptors, Antigen, T-Cell genetics, Receptors, Antigen, T-Cell metabolism, Receptors, Antigen, T-Cell, alpha-beta genetics, Receptors, Antigen, T-Cell, alpha-beta metabolism, Graft vs Host Disease etiology, Graft vs Host Disease prevention & control, Hematopoietic Stem Cell Transplantation
- Abstract
Graft-versus-host disease (GVHD) is a major risk of the administration of allogeneic chimeric antigen receptor (CAR)-redirected T cells to patients who are HLA unmatched. Gene editing can be used to disrupt potentially alloreactive T-cell receptors (TCRs) in CAR T cells and reduce the risk of GVHD. Despite the high knockout rates achieved with the optimized methods, a subsequent purification step is necessary to obtain a safe allogeneic product. To date, magnetic cell separation (MACS) has been the gold standard for purifying TCRα/β- CAR T cells, but product purity can still be insufficient to prevent GVHD. We developed a novel and highly efficient approach to eliminate residual TCR/CD3+ T cells after TCRα constant (TRAC) gene editing by adding a genetically modified CD3-specific CAR NK-92 cell line during ex vivo expansion. Two consecutive cocultures with irradiated, short-lived, CAR NK-92 cells allowed for the production of TCR- CAR T cells with <0.01% TCR+ T cells, marking a 45-fold reduction of TCR+ cells compared with MACS purification. Through an NK-92 cell-mediated feeder effect and circumventing MACS-associated cell loss, our approach increased the total TCR- CAR T-cell yield approximately threefold while retaining cytotoxic activity and a favorable T-cell phenotype. Scaling in a semiclosed G-Rex bioreactor device provides a proof-of-principle for large-batch manufacturing, allowing for an improved cost-per-dose ratio. Overall, this cell-mediated purification method has the potential to advance the production process of safe off-the-shelf CAR T cells for clinical applications., (© 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
43. Qualitative Research on the Perceptions of Factors Influencing Diet and Eating Behaviors Among Primarily Latinx Seventh-Grade Students.
- Author
-
Masek E, Gonzalvez A, Rankin L, Vega de Luna B, Valdez HJ, Hartmann L, Lorenzo E, Bruening M, Marsiglia FF, Harthun M, and Vega-López S
- Subjects
- Adolescent, Female, Humans, Hispanic or Latino, Qualitative Research, Students, Male, Diet, Feeding Behavior
- Abstract
Background: Latinx youth are a population of concern, at elevated risk for chronic diseases and with poor adherence to dietary recommendations., Objectives: To examine Latinx seventh-grade students' perceptions of the factors that influence their diet and eating behaviors., Design: This qualitative research used focus groups and an inductive content analysis approach., Participants/setting: Five sex-stratified focus groups (three groups with females) with 35 primarily Latinx seventh-grade students were conducted at two local Title 1 public middle schools in a large metropolitan area of the Southwestern United States., Main Outcome Measures: The discussion protocol included questions about participants' food choices, the role of their parents in their diet, and healthy body-related concerns among their peers., Analyses: Verbatim transcripts were coded in NVivo 12 on the basis of specificity, extensiveness, and frequency. Themes emerged from group dialogue, detailed conversations, and predominant topics of discussion, and aligned with ecological systems theory., Results: Participants referred to factors influencing Latinx seventh-grade students' eating behaviors at the individual, family, household, and school levels. At the individual level, participants described their eating as unhealthy and perceived it as determined by taste, convenience, ease of preparation, and home availability. Participants expressed concerns about diabetes because of their body weight and family history, and identified those concerns as reasons for acceptance of healthy foods and the desire for parents to model healthy eating behaviors. Family-level factors perceived as influencing dietary behaviors included the role of parents as providers of food and models of unhealthy eating, budget constraints, and availability (or lack thereof) of healthy foods at home. Similarly, the identified school-level factors aligned with availability and quality of foods in that environment., Conclusions: Family- and household-related factors emerged as important influences on seventh-grade students' dietary behaviors. Future diet interventions should incorporate strategies targeting these multiple-level factors that influence dietary intake for Latinx youth and that address the concerns related to disease risk., (Copyright © 2023 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
44. Glycan-Presenting Coacervates Derived from Charged Poly(active esters): Preparation, Phase Behavior, and Lectin Capture.
- Author
-
Illmann MD, Schäfl L, Drees F, Hartmann L, and Schmidt S
- Subjects
- Polyelectrolytes chemistry, Galactose chemistry, Carbohydrates chemistry, Polysaccharides, Lectins metabolism, Mannose chemistry
- Abstract
This study presents the preparation and phase behavior of glycan-functionalized polyelectrolytes for capturing carbohydrate-binding proteins and bacteria in liquid condensate droplets. The droplets are formed by complex coacervation of poly(active ester)-derived polyanions and polycations. This approach allows for a straightforward modular introduction of charged motifs and specifically interacting units; mannose and galactose oligomers are used here as first examples. The introduction of carbohydrates has a notable effect on the phase separation and the critical salt concentration, potentially by reducing the charge density. Two mannose binding species, concanavalin A (ConA) and Escherichia coli , are shown to not only specifically bind to mannose-functionalized coacervates but also to some degree to unfunctionalized, carbohydrate-free coacervates. This suggests non-carbohydrate-specific charge-charge interactions between the protein/bacteria and the droplets. However, when mannose interactions are inhibited or when non-binding galactose-functionalized polymers are used, interactions are significantly weakened. This confirms specific mannose-mediated binding functionalization and suggests that introducing carbohydrates reduces non-specific charge-charge interactions by a so far unidentified mechanism. Overall, the presented route toward glycan-presenting polyelectrolytes enables new functional liquid condensate droplets with specific biomolecular interactions.
- Published
- 2023
- Full Text
- View/download PDF
45. Carbon dots using a household cleaning liquid as a dopant for iron detection in hydroponic systems.
- Author
-
Hjort RG, Pola CC, Casso-Hartmann L, Vanegas DC, McLamore E, and Gomes CL
- Abstract
Iron (Fe) is a required micronutrient in plants for the production of chlorophyll and transport of oxygen. A commonly used surrogate for measuring nutrient levels is the measurement of electrical conductivity or total dissolved solids, but this technique is not selective towards any particular dissolved ion. In this study, using a conventional microwave, fluorescent carbon dots (CDs) are produced from glucose and a household cleaning product and applied towards monitoring dissolved ferric iron levels in hydroponic systems through fluorescent quenching. The produced particles have an average size of 3.19 ± 0.76 nm with a relatively high degree of oxygen surface groups. When using an excitation of 405 nm, a broad emission peak is centered at approximately 500 nm. A limit-of-detection of 0.196 ± 0.067 ppm (3.51 ± 1.21 μM) with minimal interference from common heavy metal quenchers and ions found in hydroponic systems was determined. Butterhead lettuce was grown while discretely monitoring iron levels via the CDs for three separate weeks of growth. The CDs displayed a non-significant difference ( p > 0.05) in performance when compared to a standard method. These results along with a simple and relatively low-cost production method make the CDs in this study a promising tool for monitoring iron levels in hydroponic systems., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)
- Published
- 2023
- Full Text
- View/download PDF
46. Molecular Recognition of Glycan-Bearing Glycomacromolecules Presented at Membrane Surfaces by Lectins: An NMR View.
- Author
-
Lete MG, Hoffmann M, Schomann N, Martínez-Castillo A, Peccati F, Konietzny PB, Delgado S, Snyder NL, Jiménez-Oses G, Abrescia NGA, Ardá A, Hartmann L, and Jiménez-Barbero J
- Abstract
Lectin-glycan interactions are at the heart of a multitude of biological events. Glycans are usually presented in a multivalent manner on the cell surface as part of the so-called glycocalyx, where they interact with other entities. This multivalent presentation allows us to overcome the typical low affinities found for individual glycan-lectin interactions. Indeed, the presentation of glycans may drastically impact their binding by lectins, highly affecting the corresponding binding affinity and even selectivity. In this context, we herein present the study of the interaction of a variety of homo- and heteromultivalent lactose-functionalized glycomacromolecules and their lipid conjugates with two human galectins. We have employed as ligands the glycomacromolecules, as well as liposomes decorated with those structures, to evaluate their interactions in a cell-mimicking environment. Key details of the interaction have been unravelled by NMR experiments, both from the ligand and receptor perspectives, complemented by cryo-electron microscopy methods and molecular dynamics simulations., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)
- Published
- 2023
- Full Text
- View/download PDF
47. SEC14-GOLD protein PATELLIN2 binds IRON-REGULATED TRANSPORTER1 linking root iron uptake to vitamin E.
- Author
-
Hornbergs J, Montag K, Loschwitz J, Mohr I, Poschmann G, Schnake A, Gratz R, Brumbarova T, Eutebach M, Angrand K, Fink-Straube C, Stühler K, Zeier J, Hartmann L, Strodel B, Ivanov R, and Bauer P
- Subjects
- Vitamin E metabolism, alpha-Tocopherol, Biological Transport, Plant Roots metabolism, Gene Expression Regulation, Plant, Arabidopsis Proteins metabolism, Arabidopsis genetics, Arabidopsis metabolism
- Abstract
Organisms require micronutrients, and Arabidopsis (Arabidopsis thaliana) IRON-REGULATED TRANSPORTER1 (IRT1) is essential for iron (Fe2+) acquisition into root cells. Uptake of reactive Fe2+ exposes cells to the risk of membrane lipid peroxidation. Surprisingly little is known about how this is avoided. IRT1 activity is controlled by an intracellular variable region (IRT1vr) that acts as a regulatory protein interaction platform. Here, we describe that IRT1vr interacted with peripheral plasma membrane SEC14-Golgi dynamics (SEC14-GOLD) protein PATELLIN2 (PATL2). SEC14 proteins bind lipophilic substrates and transport or present them at the membrane. To date, no direct roles have been attributed to SEC14 proteins in Fe import. PATL2 affected root Fe acquisition responses, interacted with ROS response proteins in roots, and alleviated root lipid peroxidation. PATL2 had high affinity in vitro for the major lipophilic antioxidant vitamin E compound α-tocopherol. Molecular dynamics simulations provided insight into energetic constraints and the orientation and stability of the PATL2-ligand interaction in atomic detail. Hence, this work highlights a compelling mechanism connecting vitamin E with root metal ion transport at the plasma membrane with the participation of an IRT1-interacting and α-tocopherol-binding SEC14 protein., Competing Interests: Conflict of interest statement. None declared., (© The Author(s) 2022. Published by Oxford University Press on behalf of American Society of Plant Biologists.)
- Published
- 2023
- Full Text
- View/download PDF
48. Glycopolymers against pathogen infection.
- Author
-
Gerling-Driessen UIM, Hoffmann M, Schmidt S, Snyder NL, and Hartmann L
- Subjects
- Polymers chemistry, Drug Delivery Systems, Carbohydrates chemistry, Polysaccharides chemistry
- Abstract
Pathogens including viruses, bacteria, fungi, and parasites continue to shape our lives in profound ways every day. As we have learned to live in parallel with pathogens, we have gained a better understanding of the rules of engagement for how they bind, adhere, and invade host cells. One such mechanism involves the exploitation of host cell surface glycans for attachment/adhesion, one of the first steps of infection. This knowledge has led to the development of glycan-based diagnostics and therapeutics for the treatment and prevention of infection. One class of compounds that has become increasingly important are the glycopolymers. Glycopolymers are macromolecules composed of a synthetic scaffold presenting carbohydrates as side chain motifs. Glycopolymers are particularly attractive because their properties can be tuned by careful choice of the scaffold, carbohydrate/glycan, and overall presentation. In this review, we highlight studies over the past ten years that have examined the role of glycopolymers in pathogen adhesion and host cell infection, biofilm formation and removal, and drug delivery with the aim of examining the direct effects of these macromolecules on pathogen engagement. In addition, we also examine the role of glycopolymers as diagnostics for the detection and monitoring of pathogens.
- Published
- 2023
- Full Text
- View/download PDF
49. Integrated analysis of genotype and phenotype reveals clonal evolution and cytogenetically driven disruption of myeloid cell maturation in myelodysplastic syndromes.
- Author
-
Cutler JA, Pugsley HR, Bennington R, Fritschle W, Hartmann L, Zaidi N, Menssen AJ, Singleton TP, Xu D, Loken MR, Wells DA, Brodersen LE, and Zehentner BK
- Subjects
- Humans, In Situ Hybridization, Fluorescence, Flow Cytometry, Chromosome Aberrations, Phenotype, Genotype, Myeloid Cells, Myelodysplastic Syndromes genetics
- Abstract
Background: Myelodysplastic syndromes (MDS) are a heterogenous collection of clonal bone marrow diseases characterized by cytopenias, abnormal karyotypes, molecular abnormalities, and dysplasia by flow cytometry and/or morphology. The progression of MDS to severe cytopenias and/or overt leukemia is associated with the accumulation of additional cytogenetic abnormalities, suggesting clonal evolution. The impact of these accumulated abnormalities on myeloid maturation and the severity of the disease is poorly understood., Methods: Bone marrow specimens from 16 patients with cytogenetic abnormalities were flow cytometrically sorted into three myeloid populations: progenitors, immature myeloid cells, and mature myeloid cells. Fluorescence in situ hybridization analysis was performed on each to determine the distribution of chromosomal abnormalities during myeloid maturation., Results: Our findings revealed three distinct distributions of cytogenetic abnormalities across myeloid maturation, each of which corresponded to specific cytogenetic abnormalities. Group 1 had continuous distribution across all maturational stages and contained patients with a single cytogenetic aberration associated with good-to-intermediate prognosis; Group 2 had accumulation of abnormalities in immature cells and contained patients with high-risk monosomy 7; and Group 3 had abnormalities defining the founding clone equally distributed across maturational stages while subclonal abnormalities were enriched in progenitor cells and contained patients with multiple, non-monosomy 7, abnormalities with evidence of clonal evolution., Conclusions: Our findings demonstrate that low-risk abnormalities (e.g., del(20q) and trisomy 8) occurring in the founding clone display a markedly different disease etiology, with respect to myeloid maturation, than monosomy 7 or abnormalities acquired in subclones, which result in a disruption of myeloid cell maturation in MDS., (© 2021 International Clinical Cytometry Society.)
- Published
- 2023
- Full Text
- View/download PDF
50. Autopsy-based histopathological characterization of myocarditis after anti-SARS-CoV-2-vaccination.
- Author
-
Schwab C, Domke LM, Hartmann L, Stenzinger A, Longerich T, and Schirmacher P
- Subjects
- Humans, Autopsy, Vaccination, RNA, Messenger, Myocarditis diagnosis, Myocarditis etiology, COVID-19 diagnosis, COVID-19 prevention & control, Heart Failure
- Abstract
Cases of myocarditis, diagnosed clinically by laboratory tests and imaging have been described in the context of mRNA-based anti-SARS-CoV-2 vaccination. Autopsy-based description of detailed histological features of vaccine-induced myocarditis is lacking. We describe the autopsy findings and common characteristics of myocarditis in untreated persons who received anti-SARS-CoV-2 vaccination. Standardized autopsies were performed on 25 persons who had died unexpectedly and within 20 days after anti-SARS-CoV-2 vaccination. In four patients who received a mRNA vaccination, we identified acute (epi-)myocarditis without detection of another significant disease or health constellation that may have caused an unexpected death. Histology showed patchy interstitial myocardial T-lymphocytic infiltration, predominantly of the CD4 positive subset, associated with mild myocyte damage. Overall, autopsy findings indicated death due to acute arrhythmogenic cardiac failure. Thus, myocarditis can be a potentially lethal complication following mRNA-based anti-SARS-CoV-2 vaccination. Our findings may aid in adequately diagnosing unclear cases after vaccination and in establishing a timely diagnosis in vivo, thus, providing the framework for adequate monitoring and early treatment of severe clinical cases., (© 2022. The Author(s).)
- Published
- 2023
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.