Convergence of nanotechnology with radiation therapy-insights and implications for clinical translation.

Improvements in accuracy and efficacy in treating tumors with radiation therapy (RT) over the years have been fueled by parallel technological and conceptual advances in imaging and image-guidance techniques, radiation treatment machines, computational methods, and the understanding of the biology of tumor response to RT. Recent advances in our understanding of the hallmarks of cancer and the emergence of strategies to combat these traits of cancer have resulted in an expanding repertoire of targeted therapeutics, many of which can be exploited for enhancing the efficacy of RT. Complementing this advent of new treatment options is the evolution of our knowledge of the interaction between nanoscale materials and human tissues (nanomedicine).

Engineered phage-based therapeutic materials inhibit Chlamydia trachomatis intracellular infection.

Developing materials that are effective against sexually transmitted pathogens such as Chlamydia trachomatis (Ct) and HIV-1 is challenging both in terms of material selection and improving bio-membrane and cellular permeability at desired mucosal sites. Here, we engineered the prokaryotic bacterial virus (M13 phage) carrying two functional peptides, integrin binding peptide (RGD) and a segment of the polymorphic membrane protein D (PmpD) from Ct, as a phage-based material that can ameliorate Ct infection. Ct is a globally prevalent human pathogen for which there are no effective vaccines or microbicides.

Enhanced gene and siRNA delivery by polycation-modified mesoporous silica nanoparticles loaded with chloroquine.

Purpose: To prepare mesoporous silica-based delivery systems capable of simultaneous delivery of drugs and nucleic acids.

Methods: The surface of mesoporous silica nanoparticles (MSN) was modified with poly(ethylene glycol) (PEG) and poly(2-(dimethylamino)ethylmethacrylate) (PDMAEMA) or poly(2-(diethylamino)ethylmethacrylate) (PDEAEMA). The particles were then loaded with a lysosomotropic agent chloroquine (CQ) and complexed with plasmid DNA or siRNA.

N-hexanoyl chitosan-stabilized magnetic nanoparticles: enhancement of adenoviral-mediated gene expression both in vitro and in vivo.

We developed hexanoyl chloride-modified chitosan (Nac-6) stabilized iron oxide nanoparticles (Nac-6-IOPs) as magnetic nanoparticles for viral gene (Ad/LacZ) delivery via magnetofection. This vector, Nac-6-IOPs/Ad/LacZ, binds to K562 cells in the presence of external magnetic fields and results in enhanced expression of the transgene in those cells that do not exhibit the coxsackie-adenovirus receptor (CAR). Our results demonstrate that Nac-6-IOPs/Ad/LacZ is able to transduce K562 cells specifically with reduced infection of CAR- cells.

Novel production method and in-vitro cell compatibility of porous Ti-6Al-4V alloy disk for hard tissue engineering.

Porous metals are attractive due to its unique physical, mechanical, and new bone tissue ingrowth properties. In the present study, the production of highly porous Ti-6Al-4V parts by powder metallurgical technology and subsequently it's uses in in vitro bone tissue engineering is described. A space-holder method using carbamide with different particle size to produce parts with porosities between 35 and 70% were applied.

Laboratory formulated magnetic nanoparticles for enhancement of viral gene expression in suspension cell line.

One factor critical to successful gene therapy is the development of efficient delivery systems. Although advances in gene transfer technology including viral and non-viral vectors have been made, an ideal vector system has not yet been constructed. Due to the growing concerns over the toxicity and immunogenicity of viral DNA delivery systems, DNA delivery via improve viral routes has become more desirable and advantageous.

Stabilization of gold nanoparticles by hydrophobically-modified polycations.

Surface-modified gold nanoparticles have pronounced benefits in the biomedical field due to their significant interaction with delivery materials. In the present study we used hydrophobically-modified polycations (i.e.

Novel block copolymer (PPDO/PLLA-b-PEG): enhancement of DNA uptake and cell transfection.

The cationic lipid mediated uptake of plasmid DNA by cells in monolayer culture was significantly enhanced with an aqueous solution of the block copolymer poly(p-dioxanone-co-L-lactide)-b-poly(ethylene glycol) (PPDO/PLLA-b-PEG). Plasmid uptake studies with DNA encoding the beta-galactosidase gene and cytotoxicity evaluations were performed on MCF-7, NIH 3T3 and CT-26 cell lines. Transfection yields and time courses for maximum release of FITC labeled DNA in MCF-7 cells were observed and quantified by beta-galactosidase assay and spectrofluorometry, respectively.

Hydrophilic nanofibrous structure of polylactide; fabrication and cell affinity.

Microstructure and architecture of the scaffolds along with the surface chemistry exert profound effect on biological activity (cell distribution, proliferation, and differentiation). For the biological activity, scaffolds in tissue engineering have been widely designed. The objective of this study was to develop hydrophilic nanofibrous structure of polylactides (PLLA) polymer in the form of nonwoven mat by electrospinning technique, and further evaluate the fibroblast NIH3T3 cell proliferation, morphology, and cell-matrix interaction.

Deposition of gold nanoparticles on electrospun MgTiO3 ceramic nanofibers.

A simple method to deposit spherical gold nanoparticles on the surface of MgTiO3 ceramic nanofibers is presented. Electrospun MgTiO3/poly(vinyl acetate) (PVAc) hybrid nanofibers were calcined at 650 degrees C to obtain phase pure ceramic MgTiO3 nanofibers with 100-150 nm diameters. These ceramic nanofibers were immersed in an aqueous solution of HAuCl4 containing poly(vinyl alcohol) (PVA) as capping agent followed by photoreduction at 365 nm to get a novel Au-MgTiO3 nanocomposite.

Novel fabricated matrix via electrospinning for tissue engineering.

Electric field-driven fiber formation (electrospinning) is developing into a practical means for preparing novel porous filament with unusual structures and affordable mechanical properties. Polycaprolactone (PCL) was dissolved in solvent mixtures of methylene chloride/N,N-dimethyl formamide with ratios of 100/0, 75/25, and 50/50 (v/v) for electrospinning. The filament was formed by coagulation of the spinning solution following the well-known principle of phase separation in polymer solutions valid in other wet shaping processes.

Novel biodegradable electrospun membrane: scaffold for tissue engineering.

Nonwoven fibrous matrixes have been widely used as scaffolds in tissue engineering, and modification of microstructure of these matrices is needed to organize cells in three-dimensional space with spatially balanced proliferation and differentiation required for functional tissue development. The objective of this study was fabrication of nanofibrous matrix from novel biodegradable poly(p-dioxanone-co-L-lactide)-block-poly(ethylene glycol) (PPDO/PLLA-b-PEG) copolymer, and to examine cell proliferation, morphology of cell-matrix interaction with the electrospun nanofibrous matrix. The electrospun structure composed of PPDO/PLLA-b-PEG fibers with an average diameters of 380 nm, median pore size 8 microm, porosity more than 80% and mechanical strength 1.

Novel polymeric micelles of amphiphilic triblock copolymer poly (p-dioxanone-co-L-lactide)-block-poly (ethylene glycol).

Purpose: The objective of this study is to characterize the micelles of novel block copolymer of poly (p-Dioxanone-co-L-Lactide)-block-Poly (ethylene glycol) (PPDO/PLLA-b-PEG-) and evaluate its ability to induce gene transfection.

Methods: The ability of the block copolymer to self-assemble was determined by viscometery, dye solublization, NMR spectra and dynamic light scattering. The Trypan blue assay for in vitro biocompatibility of the block copolymer was carried out with NIH 3T3, CT-26 and MCF-7 cells, and beta-glactosidase assay was applied to measure the transfection efficiency of the block copolymer on MCF-7 breast cancer cell.