This review describes recent strategies for synthesizing polymers that are mostly or fully biobased and exhibit a high glass transition temperature.
Preparation of porous materials from one-dimensional polymers is challenging because the packing of polymer chains results in a dense, non-porous arrangement. Herein, we demonstrate the remarkable adaptation of an amorphous, linear, non-porous, flexible organic polymer into a three-dimensional, highly porous, crystalline solid, as the organic component of a metal-organic framework (MOF). A polymer with aromatic dicarboxylic acids in the backbone functioned as a polymer ligand upon annealing with Zn(II), generating a polymer-metal-organic framework (polyMOF). These materials break the dogma that MOFs must be prepared from small, rigid ligands. Similarly, polyMOFs contradict conventional polymer chemistry by demonstrating that linear and amorphous polymers can be readily coaxed into a highly crystalline, porous, three-dimensional structure by coordination chemistry.
Summary:Despite new antifungal treatment strategies, invasive aspergillosis (IA) remains a principal cause of infectious mortality after bone marrow transplantation (BMT). We reviewed the medical records of 93 allogeneic and 149 autologous transplant recipients during a 20 month period, with attention to cases of proven or probable IA. No autologous transplant recipient developed IA, whereas IA was seen in 15.1% of allogeneic recipients (including two of five patients with a prior history of IA despite prophylaxis), for an overall incidence of 5.8%. The median time to occurrence was 92 days post transplant, with no de novo cases developing prior to engraftment. Survival 100 days from diagnosis was 29%. Risk factors for the development of IA included у21 days of corticosteroid therapy of у1 mg/kg/day and post-transplant cytomegalovirus (CMV) infection. These two risk factors were statistically linked. Our data illustrate a shift toward a later occurrence of posttransplant IA, suggesting a need for close, prolonged surveillance in the outpatient environment. The contributory role of protracted corticosteroid use is also highlighted. These data have important implications in an era of alternate donor transplants and more intense immunosuppression. Established strategies implementing newer, less toxic antifungal agents as prophylaxis in high-risk patients are needed. sources and more profound immunosuppression, including T cell depletion techniques, which weaken host defenses in the post-engraftment period. The time of onset in autologous transplant recipients is typically during the preengraftment period, whereas later infections are often also seen in allogeneic recipients. 6 Specific knowledge of the usual time of onset and identifiable risk factors for IA is essential to the development of more effective prevention strategies and the application of new therapeutic techniques. Previously identified risk factors include age, 3,7 unrelated donor, 3,4 transplant outside of a laminar air flow room, 5 low cell dose, 7 recipient CMV seropositivity, 7 persistent or prolonged neutropenia, 5,8 early corticosteroid use for acute graft-versus-host disease (GVHD) prophylaxis, 9 high-grade acute GVHD, 1,3,4 chronic GVHD 4,8 and graft rejection. 10 Decreased risk for IA has been ascribed to housing patients in a high-efficiency particulate air (HEPA) filtered environment. 11 To our knowledge, no data exist comparing the risk for IA using different sources of harvested stem cells (peripheral blood vs bone marrow). Furthermore, the need exists for more data regarding the role of GVHD, as well as duration and dose of corticosteroids as predisposing factors for infection.In this study, we reviewed the current epidemiology of IA in the Bone Marrow Transplant Unit at the University of Florida with specific attention to the time of onset and survival. These findings were compared to those reported in a similar epidemiologic study done at this institution between 1981 and 1985. 11 Such a comparison can illustrate the effects of new tr...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.