Reduced cerebral blood flow in Alzheimer's disease (AD) may occur in early AD, which contributes to the pathogenesis and/or pathological progression of AD. Reversing this deficit may have therapeutic potential. Certain traditional Chinese herbal medicines (e.
View Article and Find Full Text PDFThe intrinsic haemolysis of an amyloid-β (Aβ) N-terminal targeting gramicidin S derivative was successfully dissociated from its Aβ oligomer-preventing activities via Ala-scanning-based regulation of molecular amphiphilicity. The representative analogue DGR-7 shows low toxicity but significant efficiency in preventing Aβ oligomers and reducing amyloid plaques in APP/PS1 transgenic AD mice.
View Article and Find Full Text PDFOne of challenge for cancer therapy is efficient delivery of anticancer agents into tumor sites to increase efficiency of drugs and reduce side effects. To overcome this challenge, we designed pH- sensitive doxorubicin prodrug (DEX-PEI-DOX) nanoparticles based on dextran-poly(ethylene imine) copolymers (DEX-PEI). The DEX-PEI-DOX conjugates were conveniently prepared by grafting PEI to dextran, and then anticancer drug doxorubicin (DOX) were conjugated to DEX-PEI through acid cleavable cis-aconityl bonds.
View Article and Find Full Text PDFIndocyanine green (ICG) nanoparticles were developed via electrostatic interactions of ICG and dextran based block copolymers (PEG-dextran(-SS-NH2)) as near-infrared (NIR) theranostic nanoparticles. The nanoparticles could be activated from "OFF" to "ON" of NIR fluorescence in an intracellular environment and used for NIR imaging and photothermal therapy.
View Article and Find Full Text PDFJ Nanosci Nanotechnol
October 2012
Targeted quantum dots have shown as an analytical and imaging tool for cancer detection and molecular imaging. Aptamers have recently been demonstrated as ideal candidates for molecular targeting applications. In the present work, quantum dots (QDs) were encapsulated with functional poly(ethylene glycol)-phospholipids to improve their solubility in water solution.
View Article and Find Full Text PDFAptamers have emerged as promising molecular probes for cancer diagnosis. However, their application for in vivo cancer imaging remains limitation due to the poor stability in blood and the degradation by nucleases. In the present study, we generated PEI/aptamer molecular complexes for cancer imaging in vivo by using deoxyribonuclease (DNase)-activatable fluorescence probes (DFProbes) to monitor DNA degradation.
View Article and Find Full Text PDFIndocyanine green (ICG) is a near-infrared (NIR) fluorescence dye for extensive biological application, but limited by its poor aqueous stability in vitro, concentration-dependent aggregation, rapid elimination from the body, and lack of target specificity. In this paper, to overcome these limitations, folate receptor-targeted, ICG dye-doped poly(d,l-lactide-co-glycolide) (PLGA) lipid nanoparticles (FA-ICG-PLGA-lipid NPs) were constructed by a single-step self-assemble and nanoprecipitation method. The prepared FA-ICG-PLGA-lipid NPs exhibited good biocompatibility, monodispersity, excellent NIR penetration ability, significant stability against photobleaching and long circulation time.
View Article and Find Full Text PDFThis work presents a method to visualize the degradation of exogenous DNA in living cells using a novel type of activatable fluorescence imaging probe. Deoxyribonuclease (DNase)-activatable fluorescence probes (DFProbes) are composed of double strands deoxyribonucleic acid (dsDNA) which is labeled with fluorophore (ROX or Cy3) and quencher on the end of one of its strands, and stained with SYBR Green I. In the absence of DNase, DFProbes produce the green fluorescence signal of SYBR Green I.
View Article and Find Full Text PDFA bifunctional nanoparticles-based carrier for simultaneous in vivo imaging and photodynamic therapy by encapsulating methylene blue (MB) alone in the phosphonate-terminated silica matrix has been developed. The phosphonate-terminated silica nanoparticles, entrapping water-soluble photosensitizer MB (MB-encapsulated PSiNPs), are synthesized by the controlled synchronous hydrolysis of tetraethoxysilane and trihydroxyl silyl propyl methyl phosphonate in the water-in-oil microemulsion. The resulting MB-encapsulated PSiNPs effectively prevent the leakage of entrapped MB from the particles and provide protection for against reduction by diaphorase.
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