Liposarcomas (LPSs) are rare malignant tumors of adipocytic origin, primarily occurring in the extremities and retroperitoneum, with thoracic involvement being exceptionally rare. This case report details the surgical management and outcomes of a recurrent intrathoracic LPS in a 65-year-old male with a history of previous mediastinal tumor resection. CT imaging revealed a recurrent tumor extending into the left pleura.
View Article and Find Full Text PDFSoft polymer nanocapsules and microgels, which can adapt their shape and, at the same time, sequester and release molecular payloads in response to an external trigger, are a challenging complement to vesicular structures like polymersomes. In this work, we report the synthesis of such capsules by photo-cross-linking of coumarin-substituted polyglycidyl ethers, which we prepared by Williamson etherification of epichlorohydrin (ECH) repeating units with 7-hydroxycoumarin in copolymers with -butyl glycidyl ether (BGE). To control capsule size, we employed the prepolymers in an o/w miniemulsion, where they formed a gel layer at the interface upon irradiation at 365 nm by [2π + 2π] photodimerization of the coumarin groups.
View Article and Find Full Text PDFGelation in the presence of cells with minimum cytotoxicity is highly desirable for materials with applications in tissue engineering. Herein, the naturally occurring polysaccharide pullulan is functionalized with thiolactones that undergo ring-opening addition of amines. As a result, the modified pullulan can be cross-linked with diamines and/or amine-containing biological substrates enhancing the system's versatility (e.
View Article and Find Full Text PDFReactive surfactants (surfmers), which are covalently attached to the surface of sub-micron sized polymer particles during emulsion polymerisation, are applied to tailor the surface functionality of polymer particles for an application of choice. We present a systematic study on the use of oligoglycidol-functionalised styrene macromolecules as surfmers in the emulsion polymerization of styrene. Firstly, we report the impact of the surfmer concentration on the particle size for polymerisations performed above and below the critical micelle concentration.
View Article and Find Full Text PDFEnzyme-catalyzed ring-opening polymerization of lactones is a method of increasing interest for the synthesis of polyesters. In the present work, we investigated which changes in the structure of lipase B (CaLB) shift the catalytic equilibrium between esterification and hydrolysis towards polymerization. Therefore, we present two concepts: (i) removing the glycosylation of CaLB to increase the surface hydrophobicity; and (ii) introducing a hydrophobic lid adapted from lipase (PsCL) to enhance the interaction of a growing polymer chain to the elongated lid helix.
View Article and Find Full Text PDFSynthetic amphiphilic copolymers with strong antimicrobial properties mimicking natural antimicrobial peptides were obtained via synthesis of an alternating copolymer of maleic anhydride and 4-methyl-1-pentene. The obtained copolymer was modified by grafting with 3-(dimethylamino)-1-propylamine (DMAPA) and imidized in a one-pot synthesis. The obtained copolymer was modified further to yield polycationic copolymers by means of quaternization with methyl iodide and dodecyl iodide, as well as by being sequentially quaternized with both of them.
View Article and Find Full Text PDFChem Commun (Camb)
February 2018
The photoinduced radical generation process has received renewed interest due to its economic and ecological appeal. Herein the light-induced cross-linking of functional polyglycidol and its post-cross-linking modification are presented. Linear polyglycidol was first functionalized with a tertiary amine in a two-step reaction.
View Article and Find Full Text PDFAntimicrobial polymers are an attractive alternative to low molecular weight biocides, because they are non-volatile, chemically stable, and can be used as non-releasing additives. Polymers with pendant quaternary ammonium groups and hydrophobic chains exhibit antimicrobial properties due to the electrostatic interaction between polymer and cell wall, and the membrane disruptive capabilities of the hydrophobic moiety. Herein, the synthesis of cationic⁻hydrophobic polyglycidols with varying structures by post-polymerization modification is presented.
View Article and Find Full Text PDFThe solubility of terpolymers containing alkyl, and perfluoroalkyl side chains as well as succinic acid moieties in the main chain, P[RMA--RMA--MAH] (R = C₄H₉- or CH-, R- = CH₄F-) with ca. 20 mol % fluorinated side chains and 10⁻22 mol % of succinic anhydride rings was tested in a number of solvents varying from water to non polar mineral oils. The polymers are well soluble in fluorinated solvents like Freon-113 and 1,3-bis(trifluoromethyl) benzene, in semi-polar solvents like chloroform, THF or lower esters and also in hydrocarbons with polymers containing dodecyl methacrylate.
View Article and Find Full Text PDFTerpolymers of homogeneous composition were prepared by free radical copolymerization of butyl or dodecyl methacrylate, 1,1,2,2-perfluorodecyl methacrylate and maleic anhydride using the continuous monomer addition technique. The copolymerization reactions were performed at 65 °C in the presence of azobisisobutyronitrile as an initiator in a mixture of methyl ethyl ketone and 1,3-bis (trifluoromethyl)benzene. The monomers and initiator are added to the reaction mixture with the same rate they are consumed in 5- and 10-fold excess compared to the initial monomer stock.
View Article and Find Full Text PDFJanus particles are of great research interest because of their reduced symmetry, which provides them with unique physical and chemical properties. Such particles can be prepared from spherical structures through colloidal assembly. Whilst colloidal assembly has the potential to be a low cost and scalable process, it typically lacks selectivity.
View Article and Find Full Text PDFQuantification of the stimuli-responsive phase transition in polymers is topical and important for the understanding and development of novel stimuli-responsive materials. The temperature-induced phase transition of poly(N-isopropylacrylamide) (PNIPAm) with one thiol end group depends on the confinement-free polymer or polymer brush-on the molecular weight and on the nature of the second end. This paper describes the synthesis of heterotelechelic PNIPAm of different molecular weights with a thiol end group-that specifically binds to gold nanorods and a hydrophilic NIPAm end group by reversible addition-fragmentation chain-transfer polymerization.
View Article and Find Full Text PDFAu and Ag nanoshells are of interest for a wide range of applications. The plasmon resonance of such nanoshells is the property of interest and can be tuned in a broad spectral regime, ranging from the ultraviolet to the mid-infrared. To date, a large number of manuscripts have been published on the optics of such nanoshells.
View Article and Find Full Text PDFThe use of bio-based building blocks for polymer synthesis represents a milestone on the way to "green" materials. In this work, two synthetic strategies for the preparation of multifunctional polymers are presented in which the key element is the functionality of homoserine lactone. First, the synthesis of a bis cyclic coupler based on a thiolactone and homoserine lactone is displayed.
View Article and Find Full Text PDFProtecting groups are commonly applied in multi-step molecular syntheses to protect one or multiple functional groups from reacting. After the reaction, they are removed from the molecule. In full analogy to this concept, we report the practical and scalable colloidal synthesis of Au semishells using polyphenylsiloxane protecting patches to prevent part of the surface of polystyrene nanoparticles from being covered with Au.
View Article and Find Full Text PDFPrevention of biomaterial-associated infections (BAI) remains a challenging problem, in particular due to the increased risk of resistance development with the current antibiotic-based strategies. Metallic orthopaedic devices, such as non-cemented implants, are often inserted under high mechanical stress. These non-cemented implants cannot be protected by e.
View Article and Find Full Text PDFBiomacromolecules
January 2017
In this manuscript, a biscyclic monomer with an epoxide and a thiolactone ring connected by a urethane bond is used for the synthesis of amino acid-functional polyelectrolytes. In a first step, lithium salts of amino acids react selectively with the thiolactone ring by ring-opening, formation of an amide bond, and a thiol group. In a second step and in the presence of a base a polymeric building block is formed by polyaddition of the thiolate to the epoxide ring.
View Article and Find Full Text PDFFull control over the ceiling temperature (T) enables a selective transition between the monomeric and polymeric state. This is exemplified by the conversion of the monomer 2-allyloxymethyl-2-ethyl-trimethylene carbonate (AOMEC) to poly(AOMEC) and back to AOMEC within 10 h by controlling the reaction from conditions that favor ring-opening polymerization (T > T) (where T is the reaction temperature) to conditions that favor ring-closing depolymerization (T < T). The ring-closing depolymerization (RCDP) mirrors the polymerization behavior with a clear relation between the monomer concentration and the molecular weight of the polymer, indicating that RCDP occurs at the chain end.
View Article and Find Full Text PDFVarious potential anti-infection strategies can be thought of for biomaterial implants and devices. Permanent, tissue-integrated implants such as artificial joint prostheses require a different anti-infection strategy than, for instance, removable urinary catheters. The different requirements set to biomaterials implants and devices in different clinical applications call for tailor-made strategies.
View Article and Find Full Text PDFThe enzymatic ring-opening polymerization of lactones is a method of increasing interest for the synthesis of biodegradable and biocompatible polymers. In the past it was shown that immobilization of lipase B (CaLB) and the reaction medium play an important role in the polymerization ability especially of medium ring size lactones like ε-caprolactone (ε-CL). We investigated a route for the preparation of compartmentalized microgels based on poly(glycidol) in which CaLB was immobilized to increase its esterification ability.
View Article and Find Full Text PDFWe demonstrate specific interface-templated crystallization behavior of biocompatible amphiphilic poly(ethylene oxide)--poly(ε-caprolactone) (PEO--PCL) block copolymers enabling triggered shaping of the curvature of the oil/water interface and controlled phase inversion, including the formation of stable multiple emulsions. Water-born anisotropic micelles of PEO--PCL block copolymers self-assemble at the oil-water interface in a multilayer form and undergo conformational rearrangements into unique semicrystalline multilamellar shells, for which curvature (type of emulsion) can be tuned by the molecular architecture (volume fractions of the blocks) and/or by the temperature. The latter trigger affects both the solubility of the PEO block in water and the semicrystalline state of the PCL block.
View Article and Find Full Text PDFFemale adnexal tumors of probable Wolffian origin (FATWO) are rare tumors, which are mostly localized in the broad ligament or the mesosalpinx. They show high intratumor and intertumor variability of histological patterns (e.g.
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