The Barnase-Barstar-based pre-targeting strategy for enhanced antitumor therapy in vivo.

There is a great need for novel approaches to the treatment of epithelial ovarian carcinoma, which is the leading cause of mortality from gynecological malignancies. In this study, the pre-targeting technology was used to enhance the in vivo targeting of cytotoxic module composed of nanoliposomes loaded with a truncated form of Pseudomonas aeruginosa exotoxin A (PE40) to cancer cells. Pre-targeting system used in this study is composed of bacterial ribonuclease Barnase and its natural antitoxin Barstar.

Flash drug release from nanoparticles accumulated in the targeted blood vessels facilitates the tumour treatment.

Tumour microenvironment hinders nanoparticle transport deep into the tissue precluding thorough treatment of solid tumours and metastatic nodes. We introduce an anticancer drug delivery concept termed FlaRE (Flash Release in Endothelium), which represents alternative to the existing approaches based on enhanced permeability and retention effect. This approach relies on enhanced drug-loaded nanocarrier accumulation in vessels of the target tumour or metastasised organ, followed by a rapid release of encapsulated drug within tens of minutes.

Polymer/magnetite carriers functionalized by HER2-DARPin: Avoiding lysosomes during internalization and controlled toxicity of doxorubicin by focused ultrasound induced release.

Nanomedicine has revolutionized the available treatment options during the last decade, but poor selectivity of targeted drug delivery and release is still poses a challenge. In this study, doxorubicin (DOX) and magnetite nanoparticles were encapsulated by freezing-induced loading, coated with polymeric shell bearing two bi-layers of polyarginine/dextran sulphate and finally modified with HER2-specific DARPin proteins. We demonstrated that the enhanced cellular uptake of these nanocarriers predominantly occurs by SKOV-3 (HER2+) cells, in comparison to CHO (HER2-) cells, together with the controlled DOX release using low intensity focused ultrasound (LIFU).

Laser Synthesized Core-Satellite Fe-Au Nanoparticles for Multimodal In Vivo Imaging and In Vitro Photothermal Therapy.

Hybrid multimodal nanoparticles, applicable simultaneously to the noninvasive imaging and therapeutic treatment, are highly demanded for clinical use. Here, Fe-Au core-satellite nanoparticles prepared by the method of pulsed laser ablation in liquids were evaluated as dual magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents and as sensitizers for laser-induced hyperthermia of cancer cells. The biocompatibility of Fe-Au nanoparticles was improved by coating with polyacrylic acid, which provided excellent colloidal stability of nanoparticles with highly negative ζ-potential in water (-38 ± 7 mV) and retained hydrodynamic size (88 ± 20 nm) in a physiological environment.

Increased sample capacity for genotyping and expression profiling by kinetic polymerase chain reaction.

We fabricated and evaluated high-throughput kinetic thermal cyclers with 768-reaction capacity for kinetic polymerase chain reaction (kPCR)-based genotyping and kinetic reverse transcription (kRT)-PCR-based transcript quantitation. The system uses dye-based detection with ethidium bromide and a single DNA polymerase-based PCR or RT-PCR assay. Allele-specific detection of the two most common hereditary hemochromotosis mutant alleles, C282Y and H63D, was reliably measured by kPCR using human DNA templates as low as 10 genome equivalents per assay.

Deletion of C-terminal residues of Escherichia coli ribosomal protein L10 causes the loss of binding of one L7/L12 dimer: ribosomes with one L7/L12 dimer are active.

Escherichia coli ribosomal protein L10 binds the two L7/L12 dimers and thereby anchors them to the large ribosomal subunit. C-Terminal deletion variants (Delta10, Delta20, and Delta33 amino acids) of ribosomal protein L10 were constructed in order to define the binding sites for the two L7/L12 dimers and then to make and test ribosomal particles that contain only one of the two dimers. None of the deletions interfered with binding of L10 variants to ribosomal core particles.

[The effect of point amino acid substitutions on T4 phage lysozyme stability. II. Transition of a protein molecule to the "molten globule" state with replacements Asp10---His, Asn101---Asp, Arg148---Ser].

The amino acid replacements (Asp10-->His, Asn101-->Asp, Arg148-->Ser) in the T4 phage lysozyme were obtained by site directed mutagenesis and the plasmid for mutant protein expression was constructed. At acid pH (pH 2.7) the mutant is in the conformational state with properties of the molten globule (Ptitsyn, 1992): 1) the mutant protein molecule is essentially compact, 2) its circular dichroism (CD) spectrum in the near ultra violet (UV) region is drastically reduced in intensity as compared with the wild type protein spectrum, 3) the CD spectrum in the far UV region indicates the presence of a pronounced secondary structure in the mutant, 4) unlike the wild type protein, the mutant protein can bind the hydrophobic fluorescent probe ANS.

[Interaction of EcoRII restriction and modification enzymes with synthetic DNA fragments. IX. Cleavage of substrates with point modifications in the recognition site and flanking sequences].

Ability of the EcoRII restriction endonuclease to cleave 14-base-pair DNA duplexes with nucleotide substitutions in the recognition site CCA/TGG and in the adjacent base pair has been studied. Modifications leading to a local change in the substrate conformation (rU residue in and outside the recognition site, A.A- or A.

[DNA-duplexes with phosphoamide bond: interaction with restriction endonucleases EcoRII and SsoII].

We studied the interaction of EcoRII and SsoII restriction endonucleases with synthetic DNA duplexes, containing 3'N----5'P and 3'P----5'N phosphoamide internucleotide bonds in one of the cleavage points. Enzymatic hydrolysis of the modified strand of the duplexes is blocked in all cases. The presence of phosphoamide bonds was found to reduce the rate of cleavage of the natural strand by EcoRII and to have no influence in case of SsoII.