116 research outputs found
Rapid analysis of local data to inform off-label tocilizumab use early in the COVID-19 pandemic
The interleukin-6 receptor antagonist tocilizumab became widely used early in the coronavirus disease 2019 (COVID-19) pandemic based on small observational studies that suggested clinical benefit in COVID-19 patients with a hyperinflammatory state. To inform our local treatment algorithms in the absence of randomized clinical trial results, we performed a rapid analysis of the first 11 hospitalized COVID-19 patients treated with tocilizumab at our academic medical center. We report their early clinical outcomes and describe the process by which we assembled a team of diverse trainees and stakeholders to extract, analyze, and disseminate data during a time of clinical uncertainty
Polyimide foams derived from a high Tg polyimide with grafted poly(α-methylstyrene)
A new route to high-Tg, thermally stable polyimide foams has been developed. Foams were prepared by casting microphase-separated graft copolymers comprising a thermally stable main chain, polyimide, and a thermally labile graft, poly(α-methylstyrene). The copolymer compositions were designed so that the thermally labile block would be the dispersed phase. This can unzip to its monomer upon heating, and the decomposition product diffuses out of the film, leaving pores embedded in a matrix of the thermally stable component. The copolymers were synthesized through either the poly(amic acid) precursor, followed by chemical cyclodehydration to the imide form, or the poly(amic alkyl ester) precursor followed by thermal imidization. The decomposition of the α-methylstyrene in the block copolymer was studied by thermogravimetric, dynamic mechanical and thermomechanical analyses. Mild decomposition conditions were required to avoid rapid depolymerization of the α-methylstyrene and excessive plasticization of the polyimide matrix. The foams showed pore sizes with diameters ranging from less than 20 nm to over 1 µm, depending upon the synthetic route employed, and the reduction in the mass density was generally consistent with the starting composition
High-temperature polyimide nanofoams for microelectronic applications
Foamed polyimides have been developed in order to obtain thin film dielectric layers with very low dielectric constants for use in microelectronic devices. In these systems the pore sizes are in the nanometer range, thus, the term 'nanofoam'. The polyimide foams are prepared from block copolymers consisting of thermally stable and thermally labile blocks, the latter being the dispersed phase. Foam formation is effected by thermolysis of the thermally labile block, leaving pores of the size and shape corresponding to the initial copolymer morphology. Nanofoams prepared from a number of polyimides as matrix materials were investigated as well as from a number of thermally labile polymers. The foams were characterized by a variety of experiments including TEM, SAXS, WAXD, DMTA, density measurements. refractive index measurements and dielectric constant measurements. Thin film foams, with high thermal stability and low dielectric constants approaching 2.0, can be prepared using the copolymer/nanofoam approach
Peptide-Functionalized Polyurethane Coatings Prepared via Grafting-To Strategy to Selectively Promote Endothelialization
10.1002/adhm.201700944Advanced Healthcare Materials75170094
Biodegradable poly(ethylene glycol)-peptide hydrogels with well-defined structure and properties for cell delivery
Biomaterials3081453-1461BIMA
Rational design of biodegradable cationic polycarbonates for gene delivery
10.1016/j.jconrel.2011.01.020Journal of Controlled Release1521120-126JCRE
Biomimetic hydrogels for chondrogenic differentiation of human mesenchymal stem cells to neocartilage
10.1016/j.biomaterials.2010.06.001Biomaterials31287298-7307BIMA
The effects of polymeric nanostructure shape on drug delivery
10.1016/j.addr.2011.06.016Advanced Drug Delivery Reviews6314-151228-1246ADDR
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