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61.
Polyamidoamine prodrugs containing ferrocene derivatives and neridronate were successfully synthesized and characterized by NMR, FTIR, SEM, and EDX analyses. Appearance of characteristic peaks in 1H and 31P NMR or EDX spectra were used to confirm the presence of neridronate or ferrocene in the conjugates and co-conjugates. In vitro evaluation of the new materials revealed improved antimalarial activity, especially for conjugate 5 and corresponding co-conjugate 8, when compared with chloroquine and quinine. Hemolysis studies revealed that synthesized prodrugs had no effect on the integrity of the host red blood cell membrane; a direct effect on the intra-erythrocytic parasite was, however, noted. 相似文献
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Nanoformulation of Brain‐Derived Neurotrophic Factor with Target Receptor‐Triggered‐Release in the Central Nervous System 下载免费PDF全文
James M. Fay Chi‐Duen Poon Natasha Vinod Yuling Zhao Kristin Bullock Si Qin Xiang Yi William A. Banks Alexander V. Kabanov 《Advanced functional materials》2018,28(6)
Brain‐derived neurotrophic factor (BDNF) is identified as a potent neuroprotective and neuroregenerative agent for many neurological diseases. Regrettably, its delivery to the brain is hampered by poor serum stability and rapid brain clearance. Here, a novel nanoformulation is reported composed of a biocompatible polymer, poly(ethylene glycol)‐b‐poly(l ‐glutamic acid) (PEG‐PLE), that hosts the BDNF molecule in a nanoscale complex, termed here Nano‐BDNF. Upon simple mixture, Nano‐BDNF spontaneously forms uniform spherical particles with a core–shell structure. Molecular dynamics simulations suggest that binding between BDNF and PEG‐PLE is mediated through electrostatic coupling as well as transient hydrogen bonding. The formation of Nano‐BDNF complex stabilizes BDNF and protects it from nonspecific binding with common proteins in the body fluid, while allowing it to associate with its receptors. Following intranasal administration, the nanoformulation improves BDNF delivery throughout the brain and displays a more preferable regional distribution pattern than the native protein. Furthermore, intranasally delivered Nano‐BDNF results in superior neuroprotective effects in the mouse brain with lipopolysaccharides‐induced inflammation, indicating promise for further evaluation of this agent for the therapy of neurologic diseases. 相似文献
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Carlson John S.; Mitchell Angela D.; Segool Natasha 《Canadian Metallurgical Quarterly》2008,23(3):354
This article reviews the current state of evidence for the psychopharmacological treatment of children diagnosed with selective mutism within the context of its link to social anxiety disorder. An increased focus on potential medication treatment for this disorder has resulted from significant monetary and resource limitations in typical practice, parental choice in utilizing treatment from medical personnel, and children who fail to respond to psychosocial interventions. A total of 21 publications within the English literature were located. From these, data for only 57 children between the ages of 4 to 17 years have been reported, with the majority of studies utilizing single-case design or case study methodology. Yet, pharmacological data appear promising for treatment resistant cases of selective mutism. The need for additional research via efficacy/effectiveness methodologies remains. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Megan Roppolo Christopher B. Jacobs Shailesh Upreti Natasha A. Chernova M. Stanley Whittingham 《Journal of Materials Science》2008,43(14):4742-4748
In order to fully understand the formation mechanism, structure, and role of structural curvature of vanadium oxide nanotubes (VONTs), two isostructural materials (one planar and the other curved)—ethylenediammonium (enH2) intercalated V7O16 and vanadium oxide nanourchins (VONUs)—were synthesized and characterized via X-ray diffraction (XRD), electron microscopy, thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy, and magnetic measurements. The synthesis route to (enH2)V7O16 is developed using vanadium pentoxide as a starting material and employing pH control. VONUs are synthesized using n-dodecylamine as an amine template for the first time. We demonstrate that the structure of the vanadium oxide layer in these compounds is similar to that of VONTs and their magnetic properties all fit to the same model including the temperature-independent, Curie–Weiss, and spin ½ antiferromagnetic dimer contributions. The vanadium oxidation state in tubular structures appears to be higher than in planar compounds such as (eH2)V7O16 and BaV7O16. The role of the template and vanadium reduction in the formation of nanotubes is discussed. 相似文献
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Haga Steve Reeves Natasha Barua Rajeev Marculescu Diana 《The Journal of supercomputing》2005,31(1):47-62
A hardware method for functional unit assignment is presented, based on the principle that a functional unit's power consumption is approximated by the switching activity of its inputs. Since computing the Hamming distance of the inputs in hardware is expensive, only a portion of the inputs are examined. Integers often have many identical top bits, due to sign extension, and floating points often have many zeros in the least significant digits, due to the casting of integer values into floating point, and other reasons. The accuracy of these approximations is studied and the results are used to develop a simple, but effective, hardware scheme. 相似文献