Manipulating Cellular Interactions of Poly(glycidyl methacrylate) Nanoparticles Using Mixed Polymer Brushes.

There is a growing need for the development of nanoparticles, with imaging and drug delivery capabilities, to maintain cellular uptake but avoid protein attachment and recognition. In this study we have demonstrated that nanoparticles consisting of a poly(glycidyl methacrylate) (PGMA) core and a mixed brush architecture of methoxypoly(ethylene glycol) and poly(ethylenimine) (mPEG-PEI) on the surface can meet this need. Surface functionalization with PEI alone results in cellular uptake, but rapid protein attachment whereas PEG alone can avoid protein attachment but to the detriment of cellular uptake.

Prolonged glutamate excitotoxicity increases GluR1 immunoreactivity but decreases mRNA of GluR1 and associated regulatory proteins in dissociated rat retinae in vitro.

Glutamate excitotoxicity contributes to damage following injury to the central nervous system via mechanisms including changes in the expression of receptors, calcium overload, oxidative stress and cell death. Excitotoxicity is triggered by glutamate binding to receptors, including calcium permeable AMPA receptors, which can be upregulated under injury conditions. However, the transcriptional response of AMPA receptor regulatory proteins to excitotoxic conditions is unknown.

The crystal structure of a homodimeric Pseudomonas glyoxalase I enzyme reveals asymmetric metallation commensurate with half-of-sites activity.

The Zn inactive class of glyoxalase I (Glo1) metalloenzymes are typically homodimeric with two metal-dependent active sites. While the two active sites share identical amino acid composition, this class of enzyme is optimally active with only one metal per homodimer. We have determined the X-ray crystal structure of GloA2, a Zn inactive Glo1 enzyme from Pseudomonas aeruginosa.

The influence of NaYF₄:Yb,Er size/phase on the multimodality of co-encapsulated magnetic photon-upconverting polymeric nanoparticles.

We report the synthesis, characterisation and evaluation of the in vitro biocompatibility of polymeric nanoparticles with both magnetic and upconverting fluorescent properties. The particles consist of superparamagnetic iron oxide nanoparticles and upconverting NaYF4:Yb,Er nanoparticles co-encapsulated within a poly(glycidyl methacrylate) sphere. Two different upconverting nanoparticles (10 nm α-NaYF4:Yb,Er and 50 nm β-NaYF4:Yb,Er) were synthesised and the optical and magnetic properties of the composite polymeric nanoparticle systems assessed by near infra-red laser spectroscopy, SQUID magnetometry and proton relaxometry.

The cytidine deaminase signature HxE(x)n CxxC of DYW1 binds zinc and is necessary for RNA editing of ndhD-1.

In flowering plants, RNA editing involves deamination of specific cytidines to uridines in both mitochondrial and chloroplast transcripts. Pentatricopeptide repeat (PPR) proteins and multiple organellar RNA editing factor (MORF) proteins have been shown to be involved in RNA editing but none have been shown to possess cytidine deaminase activity. The DYW domain of some PPR proteins contains a highly conserved signature resembling the zinc-binding active site motif of known nucleotide deaminases.

Iron oxide-induced thermal effects on solid-state upconversion emissions in NaYF4:Yb,Er nanocrystals.

Multifunctional materials exhibiting photon upconversion show promising applications for biological imaging and sensing. In this study, we examine the solid-state upconversion emission of NaYF4:Yb,Er nanoparticles in the presence of iron oxide nanoparticles. Fe3O4 nanoparticles (6 nm) were mixed with NaYF4:Yb,Er nanoparticles (either 10 or 50 nm) in varying proportions by drying chloroform solutions of nanoparticles onto glass slides.