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Biomedical subjects

A N Baranov

Publications and source records attributed to A N Baranov.

At least 19 recordsLinked to original sources
PubMed2004

[Dependence of the efficacy of transfecting muscle fibers in vivo on electroporation conditions].

This study is a survey of in vivo experiments on transfection of laboratory mouse muscle fibers by electroporation using an original device generating electric impulses. Transfection efficiency proved to depend on DNA dose and the number of electric impulses. It can be increased significantly by electroporation at varying pulse burst polarity. At both direct electrode application to muscles and electroporation through the skin, the muscle fiber transfection was more efficient under electroporation conditions much milder than those usually reported. The use of electroporation method for gene therapy of Duchenne muscular dystrophy is discussed.

Animals↗
PubMed2003

Surface states of cobalt nanoislands on Cu111.

The electronic structure of thin Co nanoislands on Cu(111) has been investigated below and above the Fermi level (E(F)) by scanning tunneling spectroscopy at low temperature. Two surface related electronic states are found: a strong localized peak 0.31 eV below E(F) and a mainly unoccupied dispersive state, giving rise to quantum interference patterns of standing electron waves on the Co surface. Ab initio calculations reveal that the electronic states are spin polarized, originating from d3(z(2)-r(2))-minority and sp-majority bands, respectively.

Journal Article↗
PubMed2002

Trace gas detection with antimonide-based quantum-well diode lasers.

Widely tunable GaInAsSb/AlGaAsSb quantum well (QW) lasers have been grown by molecular beam epitaxy on GaSb substrates. Their emission wavelength, from 2.0 to 2.5 microm, make them suitable for the detection of many gas species in the wavelength range which corresponds to an atmospheric transmission window. Using these devices an experimental setup for open path gas detection has been developed.

Antimony↗
PubMed2002

[Gene hACR-1 suppresses apoptosis of striated muscle fibres of m. quadriceps femoris after ballistic transfection of mdx mice].

Human minidystrophin gene (pSG5dys plasmid) and hACR-1 gene (pRc-CMV-10.1 plasmid) were cotransfected by means of "gene-gun" to M. quadriceps femoris of mdx mice. Effects of transfection on dystrophin expression and survival of striated muscle fibres (SMF) were studied on the 21st day after shots. In the control mdx dystrophin-positive muscular fibers [D(+)] SMF and destroyed SMF made 2.1 +/- 0.1 and 2.1 +/- 0.3%, respectively. In mice transfected with pSG5dys plasmid (20 mkg of DNA per mouse), the shares of D(+) SMF and dead SMF raised, respectively, up to 5.6 +/- 1.4 and 4.5 +/- 0.9%. Transfection of mice with pRc-CMV-10.1 (DNA dose is 20 mkg per mouse) reduced the levels of apoptosis in SMF and D(+) SMF level to 1.6 +/- 0.6 and 1.1 +/- 0.4%, respectively. Cotransfection by pSG5dys and pRc-CMV-10.1 plasmids (10 and 10 mkg of each plasmids DNA per mouse) reduced the share of D(+) SMF to 1.1 +/- 0.5% and SMF destruction to 0.9 +/- 0.3%. pSG5dys transfection considerably reduced the share of SMF having peripherally located nuclei, thus indicating a decrease in SMF differentiation level after transfection. Cotransfection of ACR-1 gene and a dystrophin minigene did not suppress further cytodifferentiation of mdx muscle fibers. A conclusion is made that ballistic transfection by hACR-1 gene reduces the level of apoptosis in mdx mice SMF without changing the level of SMF differentiation. The cotransfection of mdx mice muscle by hACR-1 and human minidystrophin gene reduces SMF destruction and supports SMF differentiation, too.

Animals↗
PubMed2002

[The BCL-xL and ACR-1 genes promote differentiation and reduce apoptosis in muscle fibers of mdx mice].

The effects of the human BCL-xL and ACR-1 genes on dystrophin expression in cross-striated muscle fibers (CSMF) and on CSMF viability were studied in mdx mice after ballistic cotransfection with the human dystrophin minigene. In control mice, the proportion of dystrophin-positive (D(+)) and dying CSMF were 2.1 +/- 0.1 and 2.1 +/- 0.3%, respectively. Introduction of the dystrophin minigene (20 micrograms of the pSG5dys plasmid) increased the proportions of D(+) and dying CSMF to 5.6 +/- 1.4% and 4.5 +/- 0.9%, respectively. When pSG5dys was introduced along with the pSFFV-Neo plasmid carrying the BCL-xL gene (10 micrograms of each plasmid per shot), the death of CSMF decreased to 3.7 +/- 1% and the proportion of D(+) CSMF significantly (P < 0.05) increased to 12.2 +/- 2.2%. Contransfection with the dystrophin minigene and the BCL-xL gene at 20 micrograms of each plasmid per shot did not stimulate generation of D(+) CSMF, but did reduce the CSMF death to 1.5 +/- 0.3%. Introduction of pSG5dys along with the pRc-CMV-10.1 plasmid containing the ACR-1 gene (10 micrograms of each plasmid per shot) reduced the proportion of D(+) CSMF to 1.1 +/- 0.5% and significantly reduced the proportion of dying CSMF to 0.9 +/- 0.3% as compared with the proportions observed in intact mice or in mice subjected to transfection with pSG5dys. Introduction of the pSG5dys plasmid substantially reduced the proportion of CSMF with peripheral nuclei, suggesting disturbed CSMF differentiation. After cotransfection with the human-dystrophin minigene, the BCL-xL and ACR-1 genes did not affect the extent of CSMF differentiation as compared with that observed in the case of the dystrophin minigene alone. Thus, ballistic transfection of mdx mice with the human dystrophin gene used along with the BCL-xL or ACR-1 gene was shown to suppress the death of muscle fibers and to expedite dystrophin synthesis and cell differentiation.

Animals↗
PubMed2001

[Current state and prospects for gene therapy of Duchenne muscular dystrophy in the world and in Russia].

Failure of drug therapy of Duchenne muscular dystrophy (DMD) stimulated intense search for adequate methods of gene therapy (GT) which would ensure effective delivery of the dystrophin (D) gene, its long-term persistence in transfected cells, and its expression in muscle fibers. The main results of the experimental GT of DMD with the use of viral and nonviral delivery of the D gene into muscles of biological models are discussed. Delivery of a mini-gene of D with a specific muscle promoter using a modified adenoassociated virus is currently the most promising method, which will soon be available for clinical trials. The main results of the studies on the DMD GT in Russia are summarized. The results of experiments on genetic transfection of mdx mice with marker genes and various constructions with the D gene are outlined. The genes are delivered into muscles by means of gene gun, electroporation, viral oligopeptides, liposomes, microspheres, lactoferine, and other nonviral vehicles. It is emphasized that consolidation of funds and efforts of all Russian laboratories dealing with gene and cell therapy of DMD are necessary to complete the experiments and start clinical trials.

Animals↗
PubMed1999

[Features of transfection and expression of cDNA for the human dystrophin gene, delivered into muscles of mdx mice using MF-2 synthetic microspheres].

The number of dystrophin-positive myofibers (DPM), that appeared in different skeletal muscles of mdx mice after a single injection of synthetic microspheres containing the full-length human dystrophin cDNA within the pHSADy expressing vector into femoral quadriceps muscle, was examined on cryostat sections. Injection of 25 micrograms cDNA resulted in the occurrence of 1, 2.4, 5.8 and 4.8% of DPM in the treated muscle in 1, 7, 21, and 60 days after the injection respectively. 7, 21, and 60 days after the treatment, these values comprised 2.1, 4.3 and 1% in the same muscle of the contralateral leg, and 5.5, 8.4, and 1% in the gluteal muscle. Expression of the full-length human dystrophin (427 kDa) in the muscle of the transfected mdx mice was observed. The presence of the transfected construction in skeletal muscles, heart, brain, lungs, and fetuses was demonstrated PCR. Utilization of the FISH technique with biotinilated pHSADy construct as a DNA probe showed that 7 days after the injection, the MF-2 microspheres were present in 70% of myoblast nuclei, in 64% of nuclei of gluteal muscles, and in 62% of the contralateral quadriceps nuclei. 21 days after the treatment, these values were 41, 29, and 45%, respectively. The MF-2 microsphere were detected in the nuclei of the blood, brain, heart, and lung cells, as well as in the placenta and tissues of 18-day-old fetuses. Our results demonstrated the high efficiency of microsphere-mediated transfer of gene constructs into cell nuclei, their long-term intranuclear persistence, and the ability to direct expression for at least 2 months after injection. The MF-2 microspheres attract special interest in respect to the targeted delivery of gene constructs into the nuclei.

Animals↗
PubMed1998

[Expression of the human dystrophin gene in mdx mouse skeletal muscles after ballistic transfection].

"Gene-gun" ballistic transfection (BT) was used to deliver genetic constructs pMLVDy and pHSADy containing full-length cDNA of the dystrophin gene to musculus quadriceps remoris and musculus gluteus of mdx mice, which represent a natural model of Duchenne muscular dystrophy. Clusters of dystrophin-positive muscular fibers (DPMF) were immunocytochemically detected in sites exposed to BT. The average number of DPMF was 2% by the 17th day and 3% by the 60th day after BT with pMLVDy, whereas the number of revertant DPMF was 0.2% in control mice (without BT). When pHSADy was used, the average number of DPMF was 3% 20 days after BT. In this case, dystrophin was uniformly spread though the myoplasm in 3% of cells and produced a slight signal in separate regions under the sarcolemma in 10% of muscle fibers. The number of revertant DPMF increased to 0.6% after BT with naked particles and to 2.8% after BT with the marker lacZ gene, in both bombarded and contralateral legs. The number of DPMF in the corresponding muscles of the contralateral leg significantly increased and reached 2.8% by the 60th day after BT with pMLVDy and 6.7% by the 20th day after BT with pHSADy. Human dystrophin gene cDNA was detected in all skeletal muscles, heart, intestine, tongue, and brain by polymerase chain reaction (PCR) three weeks after BT. Immunoblot analysis showed that normal 427-kDa human dystrophin was synthesized in muscles of mdx mice. The results suggest applicability of BT for delivery of dystrophin constructs into muscles.

Animals↗
PubMed1998

[Expression of the human dystrophin gene in mdx mouse muscle fibers after transfection using liposomes and synthetic oligopeptides].

The number of dysrophin-positive fibers appearing in the femoral quadriceps muscle of mdx mice after injection of the full-length human dystrophin cDNA within the pHSADy plasmid was examined by means of immunohystochemical techniques. Transfection was carried out using lipofectamine (LFA), or synthetic oligopeptide complexes that provided the condensation of plasmid DNA (K8) and its release from endosomes gopeptide complexes that provided the condensation of plasmid DNA (K8) and its release from endosomes (JTS1). The LFA + pHSADy at a dose of 10 micrograms DNA did not affect the number of dystrophin-positive fibers at the site of injection (0.6-0.8%), whereas it caused a statistically significant increase in the number of these fibers in the same muscle of the contralateral leg (up to 2.3%). Injection of the SO + pHSADy complex resulted in the occurrence of dystrophin-positive muscle fibers characterized by a heterogeneous content and the distribution of dystrophin. The greatest number of dystrophin-positive fibers (about 16%) was observed under a ratio of pHSADy to K8 of 1:3 or 1:4. The observed maximal number of dystrophin-positive fibers after a single injection of SO + pHSADy was 3.8%, and it was 17.7% after three injections. These values were statistically significantly higher compared to intact mice (0.6%), the injection of pure plasmid (2.2%), or the intramuscular injection of sucrose (from 0.7 to 1.3%). A relatively high level of transfection (about 5%) was observed after an intracardiac injection of a large dose of the pHSADy (70 micrograms DNA). The perspectives of the targeted delivery of the dystrophin gene into muscles under conditions of parenteral administration are discussed.

Amino Acid Sequence↗
PubMed1995

[Effects of weak magnetic poles and water and model biological systems].

The effect of the weak variation magnetic fields on the model biological systems; i.e. the solution of dyes and proteins is investigated. The structural change of these systems under the action of the variation magnetic field of 156.4 Hz and the amplitude of 12.3 A/m was determined by the method of absorbtion and luminescent spectroscopy. It is suggested that this effect realizes through the hypothesis using the method of correlation spectroscopy of scattered light, there have been performed the studies of the structure of water and its changes at different temperatures; on dissolving of non-electrolytes and on exposure to the magnetic field of variable frequency. The accumulated data are indicative of changing the structure of water after the effect of resonance magnetic field. The influence of the weak magnetic fields on the structure of water is due to the clusters which are presented in water and controlled the optical heterogeneity of the medium. The cluster dimensions were evaluated.

Absorption↗
PubMed1992

[Prognostic possibilities in genital endometriosis].

A total of 64 patients with genital endometriosis were examined. The reference group included 120 phenotypically healthy women. The dermatoglyphic pattern of patients with genital endometriosis was defined, pointing to a genetic predisposition to genital endometriosis and reflecting the risk of its development. Together with other clinical and laboratory criteria, the dermatoglyphic studies permit an early diagnosis of endometriosis.

Adult↗
PubMedDate not supplied

[Optimization of transfection properties of DNA-lysine dendrimer complexes].

We studied the possibility of optimizing the DNA transfection properties of carriers based on lysine dendrimers of the third and the fifth generation, including those containing a chloroacetyl or a lipophilic palmitoyl moiety at C-end. The use of lysosome-destroying antibiotic chloroquine and an amphipathic polycationic nonadecapeptide JTS-1 was found to enhance the DNA transfecting properties of the lysine dendrimers. The triple complex including DNA, a lysine dendrimer of the third generation modified with lipophylic moieties of palmitic acid at its C-end, and JTS-1 was shown to be comparable in its transfecting activity to a complex containing Escort, a commercial cationic liposome carrier.

Anti-Bacterial Agents↗