Direct delivery of drugs into the nucleus is a promising nanotechnology therapy, since the nucleus is one of the most important organelles controlling cell proliferation and apoptosis. Here, we report a nucleus-targeting nanocarrier for nuclear drug delivery using a pH/enzyme dual sensitive strategy. The specific ligand PGM (PKKKRKV-GFLG-Mp), composed of nuclear localization sequence (PKKKRKV), enzyme-sensitive tetrapeptide (Gly-Phe-Leu-Gly, GFLG), and pH-sensitive molecules morpholine (Mp), was modified on poly (amidoamine) (PAMAM) by maleimide active polyethylene glycol ester (NHS-PEG-MAL) to form PAMAM-PEG-PGM.
View Article and Find Full Text PDFIn the present study, the three functions, including enhanced permeability and retention (EPR) effect, deep penetration within tumor, and receptor-mediated endocytosis, were integrated into a single platform in order to improve antitumor efficiency. A novel nanoparticle (dendrigraft poly-L-lysine@glycyrrhetinic acid@cyclohexane dicarboxylic anhydride@doxorubicin@ hyaluronic acid composite) has been successfully developed and was denoted as DGL-GA-CDA-DOX-HA. The transmission electron microscope (TEM), dynamic light scattering (DLS), polymer dispersity index (PDI), fourier transform infrared spectrometer (FTIR), and zeta potentials were used to characterize the physicochemical properties of the nanoparticles.
View Article and Find Full Text PDFHerein, a smart pH-sensitive nanoparticle (DGL-PEG-Tat-KK-DMA-DOX) was prepared to achieve the selective intracellular drug delivery. In this nanoparticle, a PEG-grafted cell penetrating peptide (PEG-Tat-KK) was designed and acted as the cell penetrating segment. By introducing the pH-sensitive amide bonds between the peptide and blocking agent (2,3-dimethylmaleic anhydride, DMA), the controllable moiety (PEG-Tat-KK-DMA) endowed the nanoparticle with a charge-switchable shell and temporarily blocked penetrating function, thus improving the specific internalization.
View Article and Find Full Text PDFA novel nanoscale molecular probe is formulated in order to reduce toxicity and side effects of antitumor drug doxorubicin (DOX) in normal tissues and to enhance the detection sensitivity during early imaging diagnosis. The mechanism involves a specific targeting of Arg-Gly-Asp peptide (RGD)-GX1 heterogeneous dimer peptide-conjugated dendrigraft poly-l-lysine (DGL)-magnetic nanoparticle (MNP) composite by αβ-integrin/vasculature endothelium receptor-mediated synergetic effect. The physicochemical properties of the nanoprobe were characterized by using transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, dynamic light scattering (DLS), and vibrating sample magnetometer.
View Article and Find Full Text PDFACS Appl Mater Interfaces
August 2013
We develop paclitaxel (PTX) and magnetic nanoparticles (MNPs) coencapsulated, surface charge-switchable, thermosensitive poly(d,l-lactic-co-glycolic acid)-l-lysine-d-galactose (PTX-MNP-PLGA-Lys-Gal) NPs for the controlled release of the anticancer drug. The novel dual signal-responsive nanovehicle is formulated to shield off target at pH 7.4 but bind avidly to tumor cells in acidity, alleviating toxicity and side effects of the drug to normal tissues.
View Article and Find Full Text PDFIn this paper we give a method of integrated treatment for cancer and drug-induced complications in the process of cancer therapy through dual-drug delivery system (DDDS). Two hydrophilic drugs, doxorubicin (an antitumor drug) and verapamil (an antiangiocardiopathy drug) combined preliminarily with chitosan shell coated on magnetic nanoparticles (MNPs), followed by entrapping into the PLGA nanoparticles. Further modification was conducted by conjugating tumor-targeting ligand, cyclo(Arg-Gly-Asp-D-Phe-Lys) (c(RGDfK)) peptide, onto the end carboxyl groups on the PLGA-NPs.
View Article and Find Full Text PDFWe developed a novel chitosan-based luminescent/magnetic hybrid nanoparticles with folate-conjugated tetrapeptide composites (CLMNPs-tetrapeptide-FA) by conjugation in situ. First, chitosan, CdTe quantum dots (QDs), and superparamagnetic iron oxide were directly gelled into ternary hybrid nanogels. Subsequently, tetrapeptides (GFFG and LGPV) and folate were conjugated orderly into the hybrid nanoparticles.
View Article and Find Full Text PDFIn this work, the chitosan-based luminescent/magnetic (CLM) nanomaterials were synthesized by direct gelation of chitosan, CdTe and superparamagnetic iron oxide into the hybrid nanogels. The morphology, sizes and properties of the nanogels prepared with different chitosan/QD/MNP ratios and under different processing parameters were researched. Fluorescence microscopy, FTIR spectra and TEM images confirmed the success of the preparation of the CLM hybrid nanogels.
View Article and Find Full Text PDFBackground: To study the rules that apparent diffusion coefficient (ADC) changes with time and space in cerebral infarction, and to provide the evidence in defining the infarction stages.
Methods: 117 work-ups in 98 patients with cerebral infarction (12 hyperacute, 43 acute, 29 subacute, 10 steady, and 23 chronic infarctions) were imaged with both conventional MRI and diffusion weighted imaging. The average ADC values, the relative ADC (rADC) values, and the ADC values or rADC values from the center to the periphery of the lesion were calculated.
Objective: To discuss the imaging manifestation and clinical value in herniation pit of femoral neck.
Methods: One case proved by operation and pathology and twenty cases with typical imaging manifestation described by Pitt were reviewed retrospectively. There were 17 males and 4 females with an average age of 53 years old(ranging from 30 to 85 years).
Comp Biochem Physiol C Toxicol Pharmacol
March 2007
This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).
View Article and Find Full Text PDFComp Biochem Physiol B Biochem Mol Biol
November 2005
This study was designed to assess the effect of ambient temperature on lipid content, lipid classes and fatty acid compositions of heart, liver, muscle and brain in oviparous lizards, Phrynocephalus przewalskii, caught in the desert area of China. Significant differences could be observed in the contents of the total lipid and fatty acid compositions among different temperatures (4, 25 and 38 degrees C). The study showed that liver and muscle were principal sites of lipid storage.
View Article and Find Full Text PDFAim: To establish 3D QSAR model of propenamides with anti-malarial activities.
Methods: Chemical synthesis combined with comparative molecular field analysis (CoMFA).
Results: Generated QSAR models for activities of inhibiting chloroquine resistive malaria (W2) and chloroquine sensitive malaria (D6).
Aim: To study the effects of opioid receptor agonists endomorphin-1 and -2 on contractile responses of rat thoracic aorta rings to phenylephrine (PE) and angiotensin II (Ang II), and their possible mechanism in vitro.
Methods: Isometric tension recording was progressed in thoracic aorta rings from Wistar rats.
Results: Pretreatment of morphine, endomorphin-1 and -2 (0.