Publications by authors named "Lina V Efimova"

3 Publications

  • Page 1 of 1

Smart Design of a pH-Responsive System Based on pHLIP-Modified Magnetite Nanoparticles for Tumor MRI.

ACS Appl Mater Interfaces 2021 Aug 29;13(31):36800-36815. Epub 2021 Jul 29.

Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), 620108 Yekaterinburg, Russia.

Magnetic FeO nanoparticles (MNPs) are often used to design agents enhancing contrast in magnetic resonance imaging (MRI) that can be considered as one of the efficient methods for cancer diagnostics. At present, increasing the specificity of the MRI contrast agent accumulation in tumor tissues remains an open question and attracts the attention of a wide range of researchers. One of the modern methods for enhancing the efficiency of contrast agents is the use of molecules for tumor acidic microenvironment targeting, for example, pH-low insertion peptide (pHLIP). We designed novel organosilicon MNPs covered with poly(ethylene glycol) (PEG) and covalently modified by pHLIP. To study the specific features of the binding of pHLIP-modified MNPs to cells, we also obtained nanoconjugates with Cy5 fluorescent dye embedded in the SiO shell. The nanoconjugates obtained were characterized by transmission electron microscopy (TEM), attenuated total reflection (ATR), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), dynamic light scattering (DLS), UV and fluorescence spectrometry, thermogravimetric analysis (TGA), CHN elemental analyses, and vibrating sample magnetometry. Low cytotoxicity and high specificity of cellular uptake of pHLIP-modified MNPs at pH 6.4 versus 7.4 (up to 23-fold) were demonstrated in vitro. The dynamics of the nanoconjugate accumulation in the 4T1 breast cancer orthotopically grown in BALB/c mice and MDA-MB231 xenografts was evaluated in MRI experiments. Biodistribution and biocompatibility studies of the obtained nanoconjugate showed no pathological change in organs and in the blood biochemical parameters of mice after MNP administration. A high accumulation rate of pHLIP-modified MNPs in tumor compared with PEGylated MNPs after their intravenous administration was demonstrated. Thus, we propose a promising approach to design an MRI agent with the tumor acidic microenvironment targeting ability.
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August 2021

Production of the recombinant antimicrobial peptide UBI in Escherichia coli.

Protein Expr Purif 2018 03 21;143:38-44. Epub 2017 Oct 21.

Siberian State Medical University, 2, Moskovsky trakt, 634050 Tomsk, Russia; National Research Tomsk Polytechnic University, 30, Lenina Ave., Tomsk 634050, Russia. Electronic address:

Radiolabeled peptides derived from ubiquicidine (UBI) are of great interest for early and highly accurate scintigraphic detection and differentiation of infection and sterile inflammation. In the present work the recombinant antimicrobial peptide UBI - a fragment of the human natural cationic peptide ubiquicidine - was produced in Escherichia coli for the first time. The insoluble expression of the peptide in fusion with ketosteroid isomerase provided high yield, about 6 mg of UBI per liter. We developed an approach to produce the antimicrobial peptide UBI, that encompasses inclusion body isolation and size exclusion chromatography. This method could be the basis for industrial biotechnological production of diagnostic system components that are in high demand.
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March 2018

Magnetic resonance imaging and spectroscopy for differential assessment of liver abnormalities induced by Opisthorchis felineus in an animal model.

PLoS Negl Trop Dis 2017 Jul 14;11(7):e0005778. Epub 2017 Jul 14.

Central Research Laboratory, Siberian State Medical University, Tomsk, Russia.

Background: European liver fluke Opisthorchis felineus, causing opisthorchiasis disease, is widespread in Russia, Ukraine, Kazakhstan and sporadically detected in the EU countries. O. felineus infection leads to hepatobiliary pathological changes, cholangitis, fibrosis and, in severe cases, malignant transformation of bile ducts. Due to absence of specific symptoms, the infection is frequently neglected for a long period. The association of opisthorchiasis with almost incurable bile duct cancer and rising international migration of people that increases the risk of the parasitic etiology of liver fibrosis in non-endemic regions determine high demand for development of approaches to opisthorchiasis detection.

Methodology/principal Findings: In vivo magnetic resonance imaging and spectroscopy (MRI and MRS) were applied for differential assessment of hepatic abnormalities induced by O. felineus in an experimental animal model. Correlations of the MR-findings with the histological data as well as the data of the biochemical analysis of liver tissue were found. MRI provides valuable information about the severity of liver impairments induced by opisthorchiasis. An MR image of O. felineus infected liver has a characteristic pattern that differs from that of closely related liver fluke infections. 1H and 31P MRS in combination with biochemical analysis data showed that O. felineus infection disturbed hepatic metabolism of the host, which was accompanied by cholesterol accumulation in the liver.

Conclusions: A non-invasive approach based on the magnetic resonance technique is very advantageous and may be successfully used not only for diagnosing and evaluating liver damage induced by O. felineus, but also for investigating metabolic changes arising in the infected organ. Since damages induced by the liver fluke take place in different liver lobes, MRI has the potential to overcome liver biopsy sampling variability that limits predictive validity of biopsy analysis for staging liver fluke-induced fibrosis.
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July 2017