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Magnetars are neutron stars with ultrastrong magnetic fields, which can be observed in x-rays. Polarization measurements could provide information on their magnetic fields and surface properties. We observed polarized x-rays from the magnetar 4U 0142+61 using the Imaging X-ray Polarimetry Explorer and found a linear polarization degree of 13.5 ± 0.8% averaged over the 2- to 8-kilo-electron volt band. The polarization changes with energy: The degree is 15.0 ± 1.0% at 2 to 4 kilo-electron volts, drops below the instrumental sensitivity ~4 to 5 kilo-electron volts, and rises to 35.2 ± 7.1% at 5.5 to 8 kilo-electron volts. The polarization angle also changes by 90° at ~4 to 5 kilo-electron volts. These results are consistent with a model in which thermal radiation from the magnetar surface is reprocessed by scattering off charged particles in the magnetosphere.

Thermoresponsive copolymer microgels based on the biocompatible monomer N-vinylcaprolactam (VCL) and the hydrophobic comonomer 4-tert-butylcyclohexylacrylate (TBCHA) with highly tunable comonomers ratio were for the first time synthesized by miniemulsion polymerization. Their physical properties in aqueous solution and at the solid interface were characterized using dynamic light scattering (DLS), atomic force microscopy (AFM) and dissipative particle dynamics (DPD) simulations. The results show a significant decrease of the swelling rate of the obtained microgels with an increase of the amount of the hydrophobic comonomer. In the case when the fraction of TBCHA is equal or higher than the fraction of VCL, the microgels become almost insensitive to the temperature changes, and the amount of water inside the microgels appeared to be diminishingly small. In the opposite case, if the VCL fraction is major, the copolymer microgels preserve their softness and deformability while being adsorbed onto a solid surface. At the same time, all samples have shown a good colloidal stability and a low polydispersity in size. Thus, the presented polymerization technique is applicable for the fabrication of microgels using hydrophobic monomers, which are not accessible by conventional precipitation polymerization. We demonstrate that the mechanical properties and the temperature-responsiveness of the copolymer microgels can be precisely adjusted by the content of the hydrophobic comonomer., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Glycosidases have long been used for the synthesis of glycosides by transglycosylation reactions. Especially glycosidases from hyperthermophilic bacteria are useful for reactions under extreme reaction conditions, e.g., in the presence of organic solvents. We herein report the facile enzymatic synthesis and purification of 2-(β-galactosyl)-ethyl methacrylate (Gal-EMA) with the recombinant hyperthermostable glycosidase from Pyrococcus woesei in high yields. Optimized reaction conditions resulted in gram-scale synthesis of the galactosylated monomer with 88% transglycosylation yield. The product Gal-EMA was characterized by high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS), nuclear magnetic resonance (NMR) spectroscopy, and infrared (IR) spectroscopy. Gal-EMA was utilized to synthesize sugar-functionalized acrylate polymers with defined amounts of incorporated galactose (0-100%). Analysis of the binding affinity of the lectin RCA 120 from Ricinus communis to the glycopolymers using an enzyme-linked lectin assay (ELLA) revealed K D values between 0.24 and 6.2 nM, depending on the amount of incorporated Gal-EMA. The potential of Gal-EMA for the synthesis of acrylate-functionalized glycan oligomers was demonstrated by sequential elongation of the terminal galactose by two glycosyltransferases, resulting in the terminal glycan N -acetyllactosamine (LacNAc) epitope. In conclusion, the enzymatic synthesis of Gal-EMA opens new routes to a series of novel monomeric building blocks for the synthesis of glycan-functionalized polyacrylates.

Enzyme immobilization has been widely used to improve the stability and recyclability of enzymes in industrial processes. In this work, a sortase-mediated and therefore selective covalent immobilization strategy (sortagging) for enzymes on microgels (GelZyms) was investigated. Aqueous microgels were synthesized from poly( N -vinylcaprolactam)/glycidyl methacrylate (PVCL/GMA) and tagged with the sortase A recognition peptide sequence (LPETG) or its nucleophilic counterpart-tag (GGG). General applicability and selective immobilization were confirmed by subsequent sortagging of five different enzymes ( Bacillus subtilis lipase A (BSLA), Yersinia mollaretii phytase (Ym-phytase), Escherichia coli copper efflux oxidase (CueO laccase), cellulase A2, and Bacillus megaterium monooxygenase P450 BM3). The latter was performed directly from the cell lysate to ensure cost-effective immobilization. All five immobilized enzymes were catalytically active and could be recycled (e.g., laccase CueO and monooxygenase P450 BM3 F87A; >55% residual activity after six cycles). Application potential was demonstrated by using CueO decorated microgels for bleaching of the synthetic dye indigo carmine.

Current nanomedicine suffers from a big challenge due to the fact that most of the nanocarrier systems lack the desired tumor penetration depth, thereby limiting their clinical translation. Unlike the nanomaterials with a similar size or shape, microgels display excellent softness, fluidity and deformability, as well as stimuli-responsiveness in the tumor microenvironment. Herein, we report the synthesis of temperature-responsive poly(N-vinylcaprolactam)/oligo (ethylene glycol) acrylate/glycidyl methacrylate (PVCL/OEGA/GMA) microgels with different hydrodynamic radii (100-500 nm), crosslinking densities, 2-methoxyethyl acrylate (MEA) contents and OEGA chain lengths using a precipitation polymerization method and the investigation of the microgels in terms of their tumor penetration capability using a multicellular tumor spheroid (MCTS) model. The prepared microgels were well characterized with different techniques. We show that regardless of the size, crosslinking density, MEA content and OEGA chain length, all microgels display the desired cytocompatibility in the given concentration range. In vitro cellular uptake data reveal that similar to 2-dimensional (2-D) adherent cells, microgels with a smaller size display more enhanced cellular uptake than those having a larger size in the 3-D MCTS model. Likewise, 3-D MCTS penetration results indicate that the PVCL/OEGA/GMA microgels with the smallest radius of 100 nm exhibit the deepest penetration length. We then selected the microgels with a radius of 200 nm but with different physicochemical parameters to investigate their cellular uptake and tumor penetration behavior. Our data show that microgels with varying crosslinking densities, MEA contents and OEGA chain lengths do not have any appreciable changes in terms of their cellular uptake and penetration in the 3-D MCTS model. Our study provides new insights for the design of different microgel-based systems for further cancer theranostic applications.

Herein, the synthesis of amylose-coated, temperature-responsive poly(N-vinylcaprolactam) (VCL)-based copolymer microgels by enzyme-catalyzed grafting-from polymerization with phosphorylase b from rabbit muscle is reported. The phosphorylase is able to recognize the oligosaccharide maltoheptaose as primer and attach glucose units from the monomer glucose-1-phosphate to it, thereby forming amylose chains while releasing inorganic phosphate. Therefore, to enable the phosphorylase-catalyzed grafting-from polymerization of glucose-1-phosphate from the PVCL-based microgels, the maltoheptaose primer is covalently attached to the microgel in the first synthesis step. This is realized by adding N-(2-aminoethyl)methacrylamide (AEMAA) as a comonomer to the PVCL microgel to integrate primary amino groups and subsequent coupling of maltoheptaonolactone. Both the PVCL/AEMAA microgel as well as the obtained microgel-maltoheptaose construct are characterized in detail by dynamic light scattering, electrophoretic mobility measurements, IR spectroscopy, and atomic force microscopy. From the microgel-maltoheptaose construct, the grafting-from polymerization of glucose-1-phosphate is performed by the addition of phosphorylase b. Atomic force microscopy images clearly demonstrate the formation of an amylose shell around the microgels. The developed amylose-coated microgels open up promising application possibilities, for example, as colloidal scavengers, since amylose helices can serve as host molecules for inclusion of hydrophobic guest molecules., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: This retrospective study analyzed benzodiazepine usage patterns in relation to guideline recommendations for the treatment of generalized convulsive status epilepticus (GCSE) as practiced by emergency medical services (EMS) and the emergency department (ED) of an inner-city hospital. Secondary outcomes of interest were adverse events and admission/discharge outcomes., Methods: Records of all patients≥18years old diagnosed with GCSE between June 2012 and September 2015 and transported by EMS to our hospital ED were reviewed., Results: Of 44 patients analyzed, 43 (98%) had a history of epilepsy. Benzodiazepine utilization varied; EMS preferred midazolam (69% of cases) while the ED utilized lorazepam (91% of cases). Benzodiazepine dosages used were lower than guideline recommendations. Seizure activity was aborted with benzodiazepines alone in 22 (50%) patients. Twelve patients (27%) experienced seizure recurrence following SE treatment and achievement of seizure cessation. Twenty-three (52%) patients required intubation after arrival to ED. All 44 patients were admitted; 30 (68%) required admission to the intensive care unit., Conclusions: There was consistent underdosing of benzodiazepines in treatment of GCSE in both EMS and ED settings likely resulting in underachievement of seizure cessation, while intubation rates were higher than reported when compared to previous studies. Prospective studies are needed to identify barriers to optimal benzodiazepine usage in GCSE patients., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In this work we explored an enzyme-mediated method for selective and efficient decoration of aqueous microgels with biomolecules. Poly(N-vinylcaprolactam) (VCL) microgels with varied amounts of glycidyl methacrylate (GMA) as comonomer incorporated in the microgel shell were synthesized and characterized in regard to their size, swelling degree, and temperature-responsiveness in aqueous solutions. The surface of the PVCL/GMA microgel containing 5 mol % glycidyl methyacrylate was modified by grafting of a specific recognition peptide sequence (LPETG) for Sortase A from Staphylococcus aureus (Sa-SrtA Δ59 ). Sortase-mediated conjugation of the enhanced Green Fluorescent Protein (eGFP) carrying a N-terminal triglycine tag to LPETG-modified microgels was successfully performed. Conjugation of eGFP to the microgel surface was qualitatively proven by confocal microscopy and by fluorescence intensity measurements. The developed protocol enables a precise control of the amount of eGFP grafted to the microgel surface as evidenced by the linear increase of fluorescence intensity of modified microgel samples. The kinetic of the sortase-mediated coupling reaction was determined by time-dependent fluorescence intensity measurements. In summary, sortase-mediated coupling reactions are a simple and powerful technique for targeted surface functionalization of stimuli-responsive microgels with biomolecules.

Herein we report the synthesis of biocompatible stimuli-responsive core-shell microgels consisting of a poly(N-vinylcaprolactam) (PVCL) core and a poly(2-methoxyethyl acrylate) (PMEA) corona via one-step surfactant-free precipitation copolymerization. The copolymerization process was investigated by reaction calorimetry, microgel growth was monitored by in situ dynamic light scattering and the chemical structure of core-shell microgels was characterized by Raman spectroscopy. It was possible to incorporate up to 32 mol% MEA into the PVCL/MEA microgels without loss of colloidal stability and broadening of the size distribution. The core-shell morphology of microgels was confirmed by transverse magnetization relaxation 1 H-NMR, dynamic light scattering (DLS), atomic force microscopy (AFM) and viscosimetry. By means of the NMR data, calorimetry and viscosity measurements it could be shown that MEA is mainly located in the microgel shell. This leads to hindered temperature-induced swelling and collapsing of the PVCL-core, as demonstrated by DLS measurements, due to the fact that the PMEA-shell exhibits a very low LCST around 5 °C. These results could also be confirmed by AFM: an increasing MEA-content leads to the formation of dense and compact core-shell microgels and results in a loss of their softness and deformability. Due to the presence of the PMEA-shell these microgels can be endocytosed much faster by HeLa cells maintaining their viability and can be suitable candidates for the design of drug carriers or imaging/diagnostic systems.

Radiation-induced pulmonary fibrosis is a severe side effect of thoracic irradiation, but its pathogenesis remains poorly understood and no effective treatment is available. In this study, we investigated the role of the extracellular adenosine as generated by the ecto-5'-nucleotidase CD73 in fibrosis development after thoracic irradiation. Exposure of wild-type C57BL/6 mice to a single dose (15 Gray) of whole thorax irradiation triggered a progressive increase in CD73 activity in the lung between 3 and 30 weeks postirradiation. In parallel, adenosine levels in bronchoalveolar lavage fluid (BALF) were increased by approximately 3-fold. Histologic evidence of lung fibrosis was observed by 25 weeks after irradiation. Conversely, CD73-deficient mice failed to accumulate adenosine in BALF and exhibited significantly less radiation-induced lung fibrosis (P < 0.010). Furthermore, treatment of wild-type mice with pegylated adenosine deaminase or CD73 antibodies also significantly reduced radiation-induced lung fibrosis. Taken together, our findings demonstrate that CD73 potentiates radiation-induced lung fibrosis, suggesting that existing pharmacologic strategies for modulating adenosine may be effective in limiting lung toxicities associated with the treatment of thoracic malignancies. Cancer Res; 76(10); 3045-56. ©2016 AACR., (©2016 American Association for Cancer Research.)

Diarrhea is a frequent complication among hospitalized patients. Nosocomial diarrhea is generally diagnosed as increased frequency and decreased consistency of stools developing after 72 hours of hospitalization. The causes of nosocomial diarrhea may be infectious or noninfectious. Noninfectious etiologies occur most commonly, and are often adverse effects of medications or enteral nutrition therapies. Infectious etiologies are most concerning and include Clostridium difficile and norovirus. Patients with nosocomial diarrhea should be placed in isolation with contact precautions in place until the presence of C difficile infection is determined. Irrespective of etiology, diarrhea can cause serious complications in hospitalized patients, including malnutrition, hemodynamic instability, metabolic acidosis, and potentially fatal pseudomembranous colitis. This article reviews nosocomial diarrhea, including its pathophysiology, infectious and noninfectious causes, and treatment strategies based on identified cause.

To study the oncogenic activity of cyclin E in an in vivo system we generated transgenic mice expressing high levels of cyclin E in T-lymphocytes by using a construct containing the CD2 locus control region. These animals were neither predisposed to develop any tumors spontaneously nor showed an increased incidence when crossbred with Emu L-myc transgenic mice but developed hyperplasia in peripheral lymphoid organs at later age with an incidence of 27%. When treated with the DNA methylating carcinogen N-methylnitrosourea (MNU) that provokes the development of T-cell lymphomas, CD2-cyclin E transgenic animals came down with T-cell neoplasia showing a significant higher incidence (54%) than normal non transgenic controls (31%). In one of eight tumors that arose in normal MNU treated mice we could find an expected activating point mutation in the Ki-ras gene (12.5%). In contrast, the same mutation occurred in five of 16 tumors from CD2-cyclin E transgenic mice (31.2%). Whereas cyclin E overexpression alone did not lead to an increased CDK2 activity we observed in all tumors that emerged from either MNU treated normal mice or treated CD2-cyclin E transgenics a downregulation of p27KIP1 and a higher histone H1 kinase activity in CDK2 immunoprecipitates compared to normal tissue. These findings demonstrate that high level expression of cyclin E can predispose T-cells for hyperplasia and malignant transformation. However, the results also suggest that this activity of cyclin E is manifest only when other cooperating oncogenes in particular ras genes are present and activated. This would be consistent with our previous finding that cyclin E and Ha-Ras cooperate in focus formation assays in rat embryo fibroblasts.

The gfi-1 gene encodes a zinc finger containing protein that is specifically expressed in T-lymphocytes and is a frequent target of proviral insertion in T-cell lymphoma provoked by infection with MoMuLV--a non acute transforming retrovirus. Expression of a gfi-1 transgene targeted to T-cells by the lck proximal promoter provokes a reduction of peripheral CD4 and CD8 positive T-cells but nevertheless weakly predisposes transgenic animals for the development of T-cell lymphoma. Forced coexpression of the serine/threonine kinase Pim-1 can partially restore normal T-cell numbers in double pim-1/gfi-1 transgenic mice. Moreover, the combinatorial expression of Pim-1 and Gfi-1 leads to accelerated development of T-cell lymphoma with a mean latency period of 114 days. A similar accelerated rate of lymphoma development was observed when lck-gfi-1 mice were crossed with mice that carry a L-myc gene targeted to be expressed at high levels in T-cells. The results show that gfi-1 can act with low activity as a dominant oncogene when overexpressed but also demonstrate that it is most efficient only in the presence of a cooperative partner protein as for example Pim-1 or L-Myc. In addition, the results suggest that Pim-1 and Gfi-1 are acting synergistically in both T-cell lymphomagenesis and T-cell development.