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The functionalization of porous microgels with polyamines is presented along with their partial conversion into carbamates with CO2 for an efficient loading and release via electrostatic interactions. The resulting ammonium carbamate particles switch their charge from negative at pH 10 to positive at pH 5 and present a zwitterionic state at pH 7. Thus, they can easily be loaded with both cationic and anionic molecules. Furthermore, the ammonium carbamate functionalization allows for an efficient release at pH values between 5.0 and 7.4, whereas classical functionalization with carboxy- or amine-groups requires pH values below pH 4 or above pH 9. This versatile and easy-to-install functionalization has a great potential for various applications, such as the loading and release of drugs or nanoparticles from hydrogels. [ABSTRACT FROM AUTHOR]

Porous colloidal particles can be tailored using templating techniques to maximize their effectiveness for a wide range of applications, including separation, catalysis, and drug delivery. However, templating usually involves harsh and complex preparation conditions, thereby complicating the fabrication of sensitive bio-functionalized particles. Here a simple, yet versatile and mild approach us used to create porous protein particles using mesoporous CaCO3 colloids as sacrificial templates. The three-step preparation procedure involves infiltrating the colloidal templates with the protein by solvent evaporation, protein crosslinking, and removal of CaCO3. Using this method one can obtain porous particles consisting of virtually any protein. To explore the applicability of the particles for various scenarios particles composed of different proteins are fabricated focusing on hemoglobin and trypsin and particle morphology, porosity, mechanical properties, the protein redox state, and enzymatic activity are determined. The results show that the nanoporous template structure is replicated and that the proteins are fully functional. By varying preparation conditions such as crosslinker concentration and protein content the elastic modulus is adjusted in the range of red blood cells. This ensures high deformability upon flow in microchannels and makes the porous protein particles a versatile platform for biomedical applications. [ABSTRACT FROM AUTHOR]

Porous poly(ethylene glycol) (PEG) microgels of both 17.6 and 8.3 μm in diameter are synthesized via hard templating with calcium carbonate (CaCO3) microparticles. The synthesis is performed in three steps: loading of PEG macromonomers into CaCO3 microparticles, crosslinking via photopolymerization, and removal of the CaCO3 template under acidic conditions. The resulting porous PEG microgels are inverse replicates of their templates as indicated by light microscopy, cryo-scanning electron microscopy (cryo-SEM), and permeability studies. Thus this process allows for the straightforward and highly reproducible synthesis of porous hydrogel particles of two different diameters and porosities that show great potential as carriers for drugs or nanomaterials. [ABSTRACT FROM AUTHOR]

Summary Genomic approaches have generated large Arabidopsis open reading frame (ORF) collections. However, molecular tools are required to characterize this ORFeome functionally. A high-throughput microtiter plate-based protoplast transactivation (PTA) system has been established that can be used in a screening approach to define which transcription factor (TF) regulates a given promoter in planta. Using to this procedure, the transactivation properties of 96 TFs can be analyzed rapidly, making use of promoter:Luciferase (LUC)-reporters and luciferase imaging. Applying GATEWAY® technology, we have established a platform to assay more than 700 Arabidopsis TFs. As a proof-of-principle, the ethylene response factor (ERF) family has been studied to evaluate this system. Importantly, distinct subsets of related ERF factors were found to activate specifically the well described target promoters RD29A and PDF1.2 that are under control of DRE or GCC box cis-elements, respectively. Furthermore, several applications of the PTA system have been demonstrated, such as analysis of transcriptional repressors, salt-inducible gene expression or functional interaction of signaling molecules like kinases and TFs. This novel molecular tool will improve functional studies on transcriptional regulation in plants significantly. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "The Characteristics of Romantic Partnerships in Women with Acquired Physical Disabilities: Intersecting and Compounded Vulnerabilities in a Community Sample in South Africa."

GRAPH Laura Hartmann GRAPH Mara Staffilani GRAPH Miriam M. Unterlass It was in 1920 when Hermann Staudinger proposed that compounds such as cellulose or proteins were long chains composed of short repeating units, in his seminal paper "Über Polimerisation" ("On Polymerization"). SP [ sp [1] SP ] sp Since this discovery 100 years ago, polymers have had a tremendous impact on our society. They show how innovative polymers are leading to new battery technologies such as metal-polymer batteries, organic batteries, polymer-air, and redox-flow batteries, which are expected to complement the current lithium-ion technologies in the future. SP [ sp [5] The quest for materials with suitable property for a specific application has been the subject of research for many years. It was an honor to work with them all and we hope that the readers will find in the articles new inspirations for their future work and our future perspectives on polymers. [Extracted from the article]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The targeted combination of organo- and biocatalysts enables the scalable conversion of inexpensive commercial substrates into a library of highly valuable enantiomerically pure synthetic building blocks for natural product synthesis. Keywords: asymmetric synthesis; biocatalysis; building blocks; one-pot reaction cascade; organocatalysis EN asymmetric synthesis biocatalysis building blocks one-pot reaction cascade organocatalysis 16715 16715 1 07/14/21 20210719 NES 210719 B Playfully easy b ! Inside Back Cover: Lewis Base-Brønsted Acid-Enzyme Catalysis in Enantioselective Multistep One-Pot Syntheses (Angew. [Extracted from the article]

Keywords: Asymmetrische Synthese; Biokatalyse; Eintopf-Reaktionskaskaden; Organokatalyse; Schlüsselbausteine DE Asymmetrische Synthese Biokatalyse Eintopf-Reaktionskaskaden Organokatalyse Schlüsselbausteine 16851 16851 1 07/14/21 20210719 NES 210719 B Spielerisch einfach b ! Der Ansatz beinhaltet neu entworfene Monomere für die radikalische Polymerisation, wie Jörg Pietruszka et al. im Forschungsartikel auf S. 16836 beschreiben. Die gezielte Kombination von Organo- und Biokatalysatoren ermöglicht die skalierbare Umsetzung preiswerter kommerzieller Substrate in eine Bibliothek wertvoller enantiomerenreiner Synthesebausteine für die Naturstoffsynthese. [Extracted from the article]

Keywords: Biokunststoff; Kristallinität; Polylactid; Ringöffnungspolymerisation; Zink DE Biokunststoff Kristallinität Polylactid Ringöffnungspolymerisation Zink 21971 21971 1 11/18/20 20201123 NES 201123 B Viele Biokunststoffe b werden mittels metallkatalysierter Ringöffnungspolymerisation hergestellt. In ihrem Forschungsartikel auf S. 21962 berichten S. Herres-Pawlis, L. Hartmann et al. über den schnellsten bekannten, robusten Katalysator für die Polymerisation von Lactid (LA) und -Caprolacton (CL). Der Zink-Guanidin-Komplex polymerisiert LA und CL in der Schmelze schnell zu farblosem Polymer mit hoher molarer Masse. [Extracted from the article]

Solid phase synthesis (SPS) is well established for the synthesis of biomacromolecules such as peptides, oligonucelotides, and oligosaccharides, and today is also used for the synthesis of synthetic macromolecules and polymers. The key feature of this approach is the stepwise assembly of building blocks on solid support, enabling monodispersity and monomer sequence control. However, in order to achieve such control, a high excess of building blocks is required during the reaction. Herein, the recovery, purification, and reusability of building blocks used in SPS, including representative examples of tailor‐made building blocks, Fmoc‐protected amino acids, and functionalized carbohydrate ligands, are reported for the first time. Results demonstrate the general applicability with recovery in high yields and high purity. Furthermore, the described recovery process can be applied in both manual and automated synthesis using a standard peptide synthesizer. Overall, this process is envisioned to be applicable for a large variety of building blocks used in the SPS of different types of molecules, and to contribute to more resourceful SPS syntheses. [ABSTRACT FROM AUTHOR]

The synthesis of brush glycopolymers mimicking the architecture of proteoglycans is achieved by grafting sequence‐defined glycooligomers derived from solid‐phase polymer synthesis onto a poly(active ester) scaffold. This approach gives access to a first library of brush glycopolymers with controlled variations in the degree of branching and number of carbohydrate ligands per branch. When studying lectin binding of linear and brush glycopolymers to lectins Concanavalin A (ConA), dendritic cell‐specific intercellular adhesion molecule‐3‐grabbing non‐integrin (DC‐SIGN), and mannose‐binding lectin (MBL), different preferences are observed with MBL showing higher binding to linear glycopolymer and ConA and DC‐SIGN favoring brush glycopolymers. This finding suggests that the architecture of polymeric glycan mimetics affects binding to lectins not only in terms of creating higher avidity but potentially also selectivity ligands. [ABSTRACT FROM AUTHOR]

Tumor-targeted immunomodulation using oncolytic viral vectors is currently being investigated as a promising strategy in cancer therapy. In a previous study, we showed that a measles virus Schwarz vaccine strain (MeVac) vector encoding an interleukin-12 fusion protein (FmIL-12) is an effective immunotherapy in the MC38cea murine colon adenocarcinoma model. We hypothesized that MeVac encoding interleukin-15 may mediate enhanced T and NK cell responses and thus increase the therapeutic efficacy, especially in NK cell-controlled tumors. Therefore, we generated MeVac vectors encoding an interleukin-15 superagonist, FmIL-15. Replication and oncolytic capacity, transgene expression, and functionality of MeVac FmIL-15 vectors were validated in vitro. Effects on the tumor immune landscape and therapeutic efficacy of both FmIL-12 and FmIL-15 vectors were studied in the MC38cea and B16hCD46 tumor models. Treatment with MeVac FmIL-15 increased T and NK cell infiltration in both models. However, MeVac FmIL-12 showed more robust viral gene expression and immune activation, resulting in superior anti-tumor efficacy. Based on these results, MeVac encoding a human IL-12 fusion protein was developed for future clinical translation. [ABSTRACT FROM AUTHOR]

The synthesis of periodic copolymers with a regularly recurring sequence in one direction along the polymeric backbone is presented, applying a step‐growth polymerization of heterofunctionalized precision macromonomers derived from solid phase synthesis (SPS) via photoinduced thiol‐ene coupling (TEC). Heterofunctional macromonomers with monomer sequence‐control of the AB type present a terminal alkene and a terminal thiol group carrying a photolabile protecting group to avoid uncontrolled polymerization by self‐initiation. As protecting group, 3,4‐methylenebisoxy‐6‐nitrobenzyl is attached onto the thiol via its bromide derivative directly on solid support. The protected heterofunctionalized macromonomer is polymerized in a two‐step procedure, first cleaving the photolabile group and subsequent polymerization of the macromonomer via TEC, giving a high molecular weight polymer with M¯n of 23.8 kDa corresponding to a X¯n of 10 with one directional sequence‐control due to their consistent head‐to‐tail linkage. A synthetic approach towards periodic copolymers with a regularly recurring sequence in one direction is presented, polymerizing a heterofunctionalized precision macromonomer derived from solid‐phase synthesis via photoinduced thiol‐ene coupling. The reactive thiol end‐group is protected, thereby preventing an uncontrolled polymerization by self‐initiation. Prior to the polymerization, the protecting group is cleaved, followed by a step‐growth polymerization of the macromonomer. [ABSTRACT FROM AUTHOR]

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 SiO2 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. [ABSTRACT FROM AUTHOR]

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 a-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 a-tocopherol-binding SEC14 protein. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A simplified and scalable one‐pot process for the anaerobic production of succinic acid using a metabolically engineered Corynebacterium glutamicum strain is demonstrated. With targeted bioprocess optimization, succinic acid titer of 78 g L−1 and yield of 1.41 molSAmolGLC−1 were achieved. Succinic acid was recovered from the neutral fermentation broth by electrochemically induced crystallization and applied for polybutylene bio‐succinate synthesis using a biocompatible zinc catalyst. Except for a slight color change, the final biopolymer was comparable to the polymer from commercial precursors. [ABSTRACT FROM AUTHOR]

Amphiphilic glycan‐functionalized oligomers are derived by solid‐phase polymer synthesis and applied in both, self‐assembled micelles as well as giant unilamellar vesicles, as simplified models of the cell's glycocalyx. Additionally, an aggregation‐induced luminophore is introduced into the amphiphilic glycomacromolecules showing no fluorescence when the molecule is free in solution. Combining glycomacromolecules carrying a binding glycan motif and the luminophore with glycomacromolecules or other amphiphiles with no binding motifs and no luminophore in self‐assembled structures, micelles and vesicles exhibiting no or only very little fluorescence are obtained. Only upon clustering of the binding glycan motifs through interaction with a multivalent lectin receptor, an increase in fluorescence is observed. Thus, clustering events within these self‐assembled structures can be detected and localized. [ABSTRACT FROM AUTHOR]

Biobanking plays a critical role in diagnostics, biomarker research and development of novel treatment approaches for various diseases. In urgent need of understanding, preventing and treating coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the importance of biobanking including data sharing and management further increased. To provide high quality tissue biomaterials and data for research and public health, the COVID-19 Autopsy and Biosample Registry was established in the state of Baden-Wuerttemberg (BW) in Germany, combining expertise and technologies of the Institutes of Pathology of the five university hospitals in BW (Heidelberg, Tübingen, Ulm, Freiburg, Mannheim). The COVID-19 Autopsy and Biosample Registry BW comprises tissue samples from autopsies and associated data of deceased patients in the context of SARS-CoV-2 infection and/or vaccination against SARS-CoV-2. The aim is to collect autopsy biospecimens, associated clinical and diagnostic data in a timely manner, register them, make them accessible for research projects and thus to support especially tissue-related research addressing COVID-19. By now, the BW network holds multiple collaborations and supported numerous publications to increase the understanding of COVID-19 disease. The achievements of the BW network as a landmark biobanking model project represent a potential blueprint for future disease-related biobanking and registry effort. [ABSTRACT FROM AUTHOR]

Purpose: Several existing field studies evaluate aluminium welding works but no thoroughly controlled exposure scenario for welding fume has been described yet. This study provides information about the uptake and elimination of aluminium from welding fumes under controlled conditions. Methods: In the Aachen Workplace Simulation Laboratory, we are able to generate welding fumes of a defined particle mass concentration. We exposed 12, until then occupationally unexposed participants with aluminium-containing welding fumes of a metal inert gas (MIG) welding process of a total dust mass concentration of 2.5 mg/m for 6 h. Room air filter samples were collected, and the aluminium concentration in air derived. Urine and plasma samples were collected directly before and after the 6-h lasting exposure, as well as after 1 and 7 days. Human biomonitoring methods were used to determine the aluminium content of the samples with high-resolution continuum source atomic absorption spectrometry. Results: Urinary aluminium concentrations showed significant changes after exposure compared to preexposure levels (mean t (0 h) 13.5 µg/L; mean t (6 h) 23.5 µg/L). Plasma results showed the same pattern but pre-post comparison did not reach significance. Conclusions: We were able to detect a significant increase of the internal aluminium burden of a single MIG aluminium welding process in urine, while plasma failed significance. Biphasic elimination kinetic can be observed. The German BAT of 60 µg/g creatinine was not exceeded, and urinary aluminium returned nearly to baseline concentrations after 7 days. [ABSTRACT FROM AUTHOR]

South Africa is a patriarchal society where women are routinely disadvantaged and subjugated, and this disadvantage is compounded by the social inequities experienced by women with physical disabilities. Patriarchal and ablest societal representations and myths work to stigmatize the sexuality of women with physical disabilities, creating barriers to participating in mutually fulfilling and equitable sexual partnerships. A dearth of information on sexual health and sexual health services tailored to the needs of persons with disabilities also creates vulnerabilities for women with physical disabilities as they engage in romantic relationships. Women with physical disabilities are more vulnerable to abuse, including emotional abuse by intimate partners than women without disabilities. The aim of this study is to explore how acquiring a physical disability from a motor-vehicle accident impacts women's romantic relationships and sense of their own sexuality, and how their altered embodiment intersects with experiences of emotional abuse and shaming societal norms. Women with acquired physical disabilities were recruited via snowball sampling and screened for eligibility, and 18 women met entrance criteria. All interview guides were translated into isiXhosa, the preferred language of participants, and trained interviewers conducted interviews. Data was analysed using thematic analysis. Women described ending romantic relationships and experiencing emotional abuse since acquiring a disability; the influence of societal norms and "culture" on romantic relationships; and the impact of disability on motherhood, and positive experiences in romantic relationships. Although some positive experiences were described, most of the findings point to the pressing need for sexual and reproductive health care services for women with physical disabilities. These services need to inform, protect, and support women through the process of reclaiming their sexual identities, and assist in the prevention of abuse. [ABSTRACT FROM AUTHOR]

The preparation of sequence‐defined macromolecules using cyclic sulfamidates on solid‐phase is outlined. The challenges surrounding an AB+CD approach are described with focus on understanding the formation of ring‐opened side products when using amide coupling reagents. To avoid undesired side product formation, a strategy of iterative ring‐openings of cyclic sulfamidates on solid‐phase is explored. Ring‐opening on primary and secondary amines is successfully reported, generating both linear and branched chain growth. However, attempts to selectively cleave N‐sulfate bearing sp3‐hybridized groups cannot be demonstrated, limiting the overall building block scope for this methodology. Consequently, the active ring‐opening of cyclic sulfamidates on amine‐functionalized oligo(amidoamine) backbones is successfully applied to produce sequence‐defined, N‐sulfated macromolecules. [ABSTRACT FROM AUTHOR]

Establishing one‐pot, multi‐step protocols combining different types of catalysts is one important goal for increasing efficiency in modern organic synthesis. In particular, the high potential of biocatalysts still needs to be harvested. Based on an in‐depth mechanistic investigation of a new organocatalytic protocol employing two catalysts {1,4‐diazabicyclo[2.2.2]octane (DABCO); benzoic acid (BzOH)}, a sequence was established providing starting materials for enzymatic refinement (ene reductase; alcohol dehydrogenase): A gram‐scale access to a variety of enantiopure key building blocks for natural product syntheses was enabled utilizing up to six catalytic steps within the same reaction vessel. [ABSTRACT FROM AUTHOR]

Die Etablierung von Eintopf‐Mehrschritt‐Protokollen, die verschiedene Arten von Katalysatoren kombinieren, ist ein wichtiges Ziel zur Steigerung der Effizienz in der modernen organischen Synthese. Insbesondere das hohe Potenzial von Biokatalysatoren muss noch ausgeschöpft werden. Basierend auf einer eingehenden mechanistischen Untersuchung eines neuen organokatalytischen Protokolls unter Verwendung zweier Katalysatoren {1,4‐Diazabicyclo[2.2.2]octan (DABCO); Benzoesäure (BzOH)} wurde eine Sequenz etabliert, die Ausgangsmaterialien für die enzymatische Veredelung (Enreduktase; Alkohol‐Dehydrogenase) bereitstellt: Indem bis zu sechs katalytische Schritte innerhalb desselben Reaktionsgefäßes genutzt wurden, konnte ein Zugang zu einer Vielzahl von enantiomerenreinen Schlüsselbausteinen für die Naturstoffsynthese im Grammmaßstab ermöglicht werden. [ABSTRACT FROM AUTHOR]

A luminophore with aggregation‐induced emission (AIE) is employed for the conjugation onto supramolecular ligands to allow for detection of ligand binding. Supramolecular ligands are based on the combination of sequence‐defined oligo(amidoamine) scaffolds and guanidiniocarbonyl‐pyrrole (GCP) as binding motif. We hypothesize that AIE properties are strongly affected by positioning of the luminophore within the ligand scaffold. Therefore, we systematically investigate the effects placing the AIE luminophore at different positions within the overall construct, for example, in the main or side chain of the olig(amidoamine). Indeed, we can show that the position within the ligand structure strongly affects AIE, both for the ligand itself as well as when applying the ligand for the detection of different biological and synthetic polyanions. [ABSTRACT FROM AUTHOR]

A novel strategy to inhibit the oncologically relevant protease Taspase1 is explored by developing PEGylated macromolecular ligands presenting the supramolecular binding motif guanidiniocarbonylpyrrole (GCP). Taspase1 requires interaction of its nuclear localization signal (NLS) with import receptor Importin α. We show the synthesis and effective interference of PEGylated multivalent macromolecular ligands with Taspase1–Importin α-complex formation. [ABSTRACT FROM AUTHOR]

Polylactide and polycaprolactone are both biodegradable polymers produced through metal‐catalyzed ring‐opening polymerization. For a truly sustainable lifecycle of these polymers it is essential to replace the industrially used cytotoxic catalyst tin(II) bis(2‐ethylhexanoate) [Sn(Oct)2] with non‐toxic alternatives. Here, we report the fastest known robust catalyst in the polymerization of lactide and ϵ‐caprolactone. This zinc guanidine catalyst can polymerize non‐purified technical rac‐lactide and ϵ‐caprolactone in the melt at different [M]/[I] ratios with fast rate constants, high molar masses, and high yields in a short time, leading to colorless, transparent polymer. Moreover, we report that polylactide and polycaprolactone produced by zinc‐guanidine complexes have favorably high crystallinities. In fact, the obtained polylactide shows a more robust degradation profile than its Sn(Oct)2‐catalysed equivalent due to a higher degree of crystallinity. [ABSTRACT FROM AUTHOR]

Polylactid und Polycaprolacton sind biologisch abbaubare Polymere, die durch metallkatalysierte Ringöffnungspolymerisation hergestellt werden. Für einen nachhaltigen Lebenszyklus dieser Polymere ist es wichtig, den industriell verwendeten zytotoxischen Katalysator [Sn(Oct)2] durch ungiftige Alternativen zu ersetzen. Wir berichten hier über den schnellsten robusten Katalysator in der Polymerisation von Lactid und ϵ‐Caprolacton. Dieser Zink‐Guanidin‐Katalysator kann unaufgereinigtes technisches rac‐Lactid und ϵ‐Caprolacton in der Schmelze bei verschiedenen [M]/[I]‐Verhältnissen mit schnellen Geschwindigkeitskonstanten, hohen Molmassen und hohen Umsätzen in kurzer Zeit polymerisieren, was zu farblosem, transparentem Polymer führt. Darüber hinaus besitzt durch diesen Komplex hergestelltes Polylactid und Polycaprolacton vorteilhafte hohe Kristallinitäten. Tatsächlich weist das erhaltene Polylactid aufgrund eines höheren Kristallinitätsgrades ein robusteres Abbauprofil auf als sein Sn(Oct)2‐katalysiertes Äquivalent. [ABSTRACT FROM AUTHOR]

The year 2020 marks the 100th anniversary of the first article on polymerization, published by Hermann Staudinger. It is Staudinger who realized that polymers consist of long chains of covalently linked building blocks. Polymers have had a tremendous impact on the society ever since this initial publication. People live in a world that is almost impossible to imagine without synthetic polymers. But what does the future hold for polymer science? In this article, the editors and advisory board of Macromolecular Chemistry and Physics reflect on this question. [ABSTRACT FROM AUTHOR]

Cholesterol self-assembles into weakly ordered aggregates when tethered to a crosslinked hydrogel network of poly(ethylene glycol) (PEG). PEG-diacrylate and cholesterol-PEG-acrylamide (PEG-chol) were co-polymerized in organic solvent and transferred to water for equilibrium swelling. Small-angle x-ray scattering revealed self-assembled cholesterol structures not present during network synthesis. At lower ratios of PEG-tethered cholesterol to PEG (<12% cholesterol based on total solid content), cholesterol aggregates into the dense, weakly ordered crosslink junctions of the PEG network. The hydrogel networks exhibited classic affine behavior during compressive mechanical testing, and cholesterol aggregation enhanced the elastic modulus. At high PEG-chol to PEG ratios (12–20% cholesterol based on total solid content), cholesterol self-assembles into domains with lamellar-like meso-ordering. The structural transition causes network deswelling and significantly reduces material brittleness upon deformation. [ABSTRACT FROM AUTHOR]

Pathogens such as viruses and bacteria use their envelope proteins and their adhesin lectins to recognize the glycan residues presented on the cell surface of the target tissues. This principle of recognition is used in a new electrochemical displacement sensor for the protein concanavalin A (ConA). A gold electrode was first modified with a self-assembled monolayer of a thiolated mannose/OEG conjugate and a ferrocene boroxol derivative was pre-assembled as reporter molecule onto the mannose surface. The novel tracer molecule based on a 2-hydroxymethyl phenyl boronic acid derivative binds even at neutral pH to the saccharides which could expand the application towards biological samples (i.e., urine and feces). Upon the binding of ConA, the tracer was displaced and washed away from the sensor surface leading to a decrease in the electrochemical signal. Using square wave voltammetry (SWV), the concentration of ConA in the sample solution could be determined in the dynamic concentration range established from 38nmolL−1 to 5.76µmolL−1 with a reproducible detection limit of 1µgmL−1 (38nmolL−1) based on the signal-to-noise ratio (S/N=3) with fast response of 15min. The new reporter molecule showed a reduced non-specific displacement by BSA and ribonuclease A. The sensor was also successfully transferred to the first proof of principle for the detection of Escherichia coli exhibiting a detection limit of approximately 6×102 cells/mL. Specificity of the displacement by target protein ConA and E. coli was demonstrated since the control proteins (i.e., BSA and RNaseA) and the control E. coli strain, which lack of type 1 fimbriae, were ineffective. [ABSTRACT FROM AUTHOR]

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.)