Search results for "Peg"
showing 10 items of 460 documents
Nanoparticle Assembly of Surface-Modified Proteins
2016
Nature's biomaterials such as peptides and proteins represent a valuable source of highly defined macromolecules. Herein we developed a nanoparticle drug delivery system based on the assembly of surface-modified proteins that can be transferred into organic solvents and represent the structural material of the carrier system. The particles are prepared by an oil-in-water nanoemulsion technique without the need of additional denaturation or cross-linking steps for stabilization. We achieve the necessary lipophilic solubility switch of the protein material by high surface PEGylation under conservation of the native three-dimensional protein structure. This study focuses on lysozyme as model e…
Catechol-Initiated Polyethers: Multifunctional Hydrophilic Ligands for PEGylation and Functionalization of Metal Oxide Nanoparticles
2012
Bifunctional CA-PEG (catechol-poly(ethylene glycol)) and multifunctional CA-PEG-PGA/PEVGE (poly(glycidyl amine)/poly(ethylene glycol vinyl glycidyl ether)) ligands for the functionalization and solubilization of nanoparticles are introduced. Tunable polymers with polydispersities1.25 and molecular weights in the range 500-7700 g mol(-1) containing a catechol moiety for conjugation to metal oxide nanoparticles were prepared. The functional PEG ligands were synthesized starting from the acetonide-protected catechol initiator 2,2-dimethyl-1,3-benzodioxole-5-propanol (CA-OH) for oxyanionic polymerization. CA-OH was used both for homopolymerization of ethylene oxide (EO) as well as copolymerizat…
Surface Modification of Polysaccharide-Based Nanoparticles with PEG and Dextran and the Effects on Immune Cell Binding and Stimulatory Characteristic…
2017
Surface modifications of nanoparticles can alter their physical and biological properties significantly. They effect particle aggregation, circulation times, and cellular uptake. This is particularly critical for the interaction with primary immune cells due to their important role in particle processing. We can show that the introduction of a hydrophilic PEG layer on the surface of the polysaccharide-based nanoparticles prevents unwanted aggregation under physiological conditions and decreases unspecific cell uptake in different primary immune cell types. The opposite effect can be observed with a parallel-performed introduction of a layer of low molecular weight dextran (3.5 and 5 kDa) on…
Evolution of the leucine gene cluster in Buchnera aphidicola: insights from chromosomal versions of the cluster.
2004
ABSTRACT In Buchnera aphidicola strains associated with the aphid subfamilies Thelaxinae, Lachninae, Pterocommatinae, and Aphidinae, the four leucine genes ( leuA , - B , - C , and - D ) are located on a plasmid. However, these genes are located on the main chromosome in B. aphidicola strains associated with the subfamilies Pemphiginae and Chaitophorinae. The sequence of the chromosomal fragment containing the leucine cluster and flanking genes has different positions in the chromosome in B. aphidicola strains associated with three tribes of the subfamily Pemphiginae and one tribe of the subfamily Chaitophorinae. Due to the extreme gene order conservation of the B. aphidicola genomes, the v…
Keyhole limpet hemocyanin (KLH), I: Reassociation from Immucothel® followed by separation of KLH1 and KLH2
1997
Abstract Studies of keyhole limpet hemocyanin (KLH) normally require purification of functional complexes directly from living animals. An alternative procedure is described wherein a commercial preparation of KLH which is fully dissociated into its subunits (Immucothel®, biosyn Arzneimittel GmbH) is reassociated in the presence of a high concentration of calcium and magnesium. The reassociation products, when observed by electron microscopy, consist of didecamers, multidecamers and flexible tubules of varying length. The two forms of KLH described previously and designated KLH1 and KLH2, are present in the reassocated mixture as homo-oligomers/polymers and can be separated by selective dis…
Hepatitis C virus (HCV) infection: a systemic disease.
2007
Abstract Hepatitis C virus (HCV) infection is a global health problem, being the second most common chronic viral infection in the world with a global prevalence of about 3% (about 180 million people). HCV is both an hepatotropic and a lymphotropic virus; and chronic infection could cause, on one hand, chronic hepatitis, cirrhosis and hepatocellular carcinoma and on the other hand several extrahepatic diseases including, first, mixed cryoglobulinemia and lymphoma. The association between hepatic (hepatocellular carcinoma) and extrahepatic (lymphoma, thyroid cancer) malignancies has justified the inclusion of HCV among human cancer viruses. The pathogenesis of HCV-related sequelae (hepatic o…
Por una rebeldía sin resentimiento: contra la desigualdad obscena y el populismo
2017
El autor analiza como causas del malestar actual de la sociedad, de un lado, la indiferencia del sector mejor situado de la población ante el crecimiento de una desigualdad obscena. Y de otro la extensión de los populismos, basados en el resentimiento, fruto de un narcisismo carente de sentido de responsabilidad. Frente a ambos extremos propone una rebeldía contra la injusticia social y económica, que debe ir acompañada del agradecimiento ante la maravilla de la creación. The author approaches the reasons for the general lack of satisfaction in civil society: on one hand the indiference of those who are in a better position and on the other the increase of populism based on resentment and n…
Early discontinuation of ribavirin in HCV-2 and HCV-3 patients responding to Peg-interferon alpha-2° and ribavirin
2009
SUMMARY. Guidelines for the treatment of patients infected with hepatitis C virus of genotypes 2 and 3 (HCV-2 and HCV-3, respectively) recommend a 24-week course of Peginterferon (Peg-IFN) alpha-2a combined with ribavirin, despite 50% of patients in registration trials attaining a sustained virologic response (SVR) following Peg-IFN alpha-2a monotherapy. The aim of this study was to delineate patient characteristics that might help to identify individuals likely to benefit from ribavirin discontinuation. One hundred and forty-four HCV-2- and HCV-3-infected patients initiated Peg-IFN alpha-2a (180 lg ⁄ week) and ribavirin (1000 or 1200 mg⁄ day); those with viral clearance at week 4 were rand…
Il collettivo secondo Margaret Gilbert: impegno congiunto ed soggetto plurale
2019
Quando possiamo considerare un insieme di individui un collettivo, un gruppo sociale? E' questa la domanda attorno a cui converge la riflessione che condurrò nelle pagine seguenti sul rapporto tra individui e collettività nel processo di formazione di quest'ultima. Oggi discutere di individuo e collettività significa discutere di ontologia sociale: quella branca della filosofia che si è sviluppata dagli anni '80 del secolo scorso fino ai giorni nostri e che si occupa di analizzare la realtà il cui artefice è l'uomo e che viene chiamata realtà sociale, poiché ha bisogno, almeno all'inizio, di un riconoscimento collettivo da parte di un gruppo più o meno ampio di soggetti. Dunque, come ci spi…
An efficient hardware implementation of MQ decoder of the JPEG2000
2014
Abstract JPEG2000 is an international standard for still images intended to overcome the shortcomings of the existing JPEG standard. Compared to JPEG image compression techniques, JPEG2000 standard has not only better not only has better compression ratios, but it also offers some exciting features. As it’s hard to meet the real-time requirement of image compression systems by software, it is necessary to implement compression system by hardware. The MQ decoder of the JPEG2000 standard is an important bottleneck for real-time applications. In order to meet the real-time requirement we propose in this paper a novel architecture for a MQ decoder with high throughput which is comparable to tha…