Federal Almazov Medical Research Center

Saint Petersburg, Russia

Federal Almazov Medical Research Center

Saint Petersburg, Russia
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Minullina I.R.,Federal Almazov Medical Research Center | Alexeyeva N.P.,Saint Petersburg State University | Anisimov S.V.,Federal Almazov Medical Research Center | Puzanov M.V.,Federal Almazov Medical Research Center | And 4 more authors.
Cell Cycle | Year: 2014

It is proposed that patients with heart failure may have not only myocardial dysfunction, but also a reduced regenerative capacity of stem cells. However, very little is known about bone marrow stromal cell (BMSC) characteristics in heart failure and its comorbidities (obesity and/or diabetes). We hypothesized that metabolic alterations associated with the latter will be reflected in altered expression of key genes related to angiogenesis, inflammation, and tissue remodeling in patient-derived BMSCs. We found that BMSCs of heart failure patients with lower body mass index have enhanced expression of genes involved in extracellular matrix remodeling. In particular, body mass index <30 was associated with upregulated expression of genes encoding collagen type I, proteases and protease activators (MMP2, MMP14, uPA), and regulatory molecules (CTGF, ITGβ5, SMAD7, SNAIL1). In contrast, these transcript levels did not differ significantly between BMSCs from obese heart failure patients and healthy subjects. Comorbidities (including obesity and diabetes) are known to play role in heart failure progression rate and outcome of the disease. We thus suggest that key molecular targets identified in this study should become the target of the subsequent focused studies. In the future, these targets may find some use in the clinical setting. © 2014 Landes Bioscience.


PubMed | St. Petersburg State Medical University, Hoffmann-La Roche, Queen Mary, University of London, Center City Clinical Hospital 31 and Federal Almazov Medical Research Center
Type: | Journal: Multiple sclerosis and related disorders | Year: 2016

Clinical trials of IV-rituximab have proved successful. It is unclear whether intrathecal (IT)-rituximab is more efficacious at lower doses. We examine its effects on B-cell biomarkers.MS patients received IT-rituximab at 3 time-points. CSF and serum samples were obtained at up to 5 time-points (days 0, 7, 14, 56 and 112). Serum and CSF BAFF and CXCL13, and CSF kappa and lambda free light chains (FLC) were measured. Flow cytometry was performed, examining effects on lymphocytes, CD3-19+ and CD3-20+ cells.CSF BAFF fell following rituximab (p=0.0091 absolute values, p=0.0284 change from baseline) whilst serum BAFF increased across time-points 1-4 (p=0.0005 absolute values, p=0.0017 change from baseline). There were significant reductions in CD20+ and CD19+ cells in blood from baseline (p<0.0001) but not in CSF. CSF kappa FLC levels significantly increased (p=0.0480).BAFF levels fall in CSF but increase in serum following IT-rituximab. Rituximab appears to act peripherally with dramatic decreases in peripheral CD20+ and CD19+ cells. It is likely that CSF B-cell counts were too low to enable differences to be seen. The rapid reduction in B-cells suggests rituximab has immediate effects. The profound depletion of B-cells, despite low doses of rituximab, underlines rituximabs efficacy.


PubMed | Federal Almazov Medical Research Center and Saint Petersburg State University
Type: Journal Article | Journal: Biomeditsinskaia khimiia | Year: 2016

The level of peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC1) in human blood plasma was investigated. Samples of healthy individuals (n=34) and patients with cardiovascular diseases (n=110), including aortic aneurysm (n=69), aortic stenosis (n=25) and patients without aortic pathologies were analyzed. In patients the PGC1 concentration was higher than that in healthy persons, and tended to decrease with age. Elevated concentrations of lactic acid, total homocysteine and asymmetric dimethylarginine in the blood of patients suggested a parallel development of endothelial and secondary mitochondrial dysfunction. However, concentrations of lactic and pyruvic acids exceeding reference limit were associated with the decrease in the PGC1 level.


PubMed | Federal Almazov Medical Research Center, Saint Petersburg State University and Institute of Molecular Biology and Genetics
Type: | Journal: BioMed research international | Year: 2015

Congenital heart defects (CHDs) often have genetic background due to missense mutations in cardiomyocyte-specific genes. For example, cardiac actin was shown to be involved in pathogenesis of cardiac septum defects and smooth muscle actin in pathogenesis of aortic aneurysm in combination with patent ductus arteriosus (PDA). In the present study, we further searched for mutations in human -cardiac actin (ACTC1) and smooth muscle -actin (ACTA2) genes as a possible cause of atrial septum defect type II (ASDII) and PDA.Total genomic DNA was extracted from peripheral blood of 86 individuals with ASDs and 100 individuals with PDA. Coding exons and flanking intron regions of ACTC1 (NM_005159.4) and ACTA2 (NM_001613) were amplified by PCR with specific primers designed according to the corresponding gene reference sequences. PCR fragments were directly sequenced and analyzed. Sequence analysis of ACTC1 and ACTA2 did not identify any nucleotide changes that altered the coding sense of the genes. In ACTC1 gene, we were able to detect one previously described nucleotide polymorphism (rs2307493) resulting in a synonymous substitution. The frequency of this SNP was similar in the study and control group, thus excluding it from the possible disease-associated variants.Our results confirmed that the mutations in ACTC1 gene are rare (at least <1%) cause of ASDII. Mutations in ACTA2 gene were not detected in patients with PDA, thus being excluded from the list of frequent PDA-associated genetic defects.


PubMed | Stereotaxis, Federal Almazov Medical Research Center, Russian Academy of Sciences and EP Solutions SA
Type: Clinical Trial | Journal: Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology | Year: 2015

Use of a non-invasive electrocardiographic mapping system may aid in rapid diagnosis of atrial or ventricular arrhythmias or the detection of ventricular dyssynchrony. The aim of the present study was to validate the mapping accuracy of a novel non-invasive epi- and endocardial electrophysiology system (NEEES).Patients underwent pre-procedural computed tomography or magnetic resonance imaging of the heart and torso. Radiographic data were merged with the data obtained from the NEEES during pacing from implanted pacemaker leads or pacing from endocardial sites using an electroanatomical mapping system (CARTO 3, Biosense Webster). The earliest activation as denoted on the NEEES three-dimensional heart model was compared with the true anatomic location of the tip of the pacemaker lead or the annotated pacing site on the CARTO 3 map. Twenty-nine patients [mean age: 62 11 years, 6/29 (11%) female, 21/29 (72%) with ischaemic cardiomyopathy] were enrolled into the pacemaker verification group. The mean distance from the non-invasively predicted pacing site to the anatomic reference site was 10.8 5.4 mm for the right atrium, 7.7 5.8 mm for the right ventricle, and 7.9 5.7 mm for the left ventricle activated via the coronary sinus lead. Five patients [mean age 65 4 years, 2 (33%) females] underwent CARTO 3 verification study. The mean distance between non-invasively reconstructed pacing site and the reference pacing site was 7.4 2.7 mm for the right atrium, 6.9 2.3 mm for the left atrium, 6.5 2.1 mm for the right ventricle, and 6.4 2.2 for the left ventricle, respectively.The novel NEEES was able to correctly identify the site of pacing from various endo- and epicardial sites with high accuracy.


Smolina N.,Karolinska Institutet | Smolina N.,Federal Almazov Medical Research Center | Bruton J.,Karolinska Institutet | Sjoberg G.,Karolinska Institutet | And 3 more authors.
Cell Calcium | Year: 2014

Desmin, being a major intermediate filament of mature muscle cell, interacts with mitochondria within the cell and participates in mitochondria proper localization. The goal of the present study was to assess the effect of aggregate-prone and non-aggregate-prone desmin mutations on mitochondrial calcium uptake. Primary murine satellite cells were transduced with lentiviruses carrying desmin in wild type or mutant form, and were induced to differentiate into myotubes. Four mutations resulting in different degree of desmin aggregates formation were analyzed. Tail domain mutation Asp399Tyr has the mildest impact on desmin filament polymerization, rod domain mutation Ala357Pro causes formation of large aggregates composed of filamentous material, and Leu345Pro and Leu370Pro are considered to be the most severest in their impact on desmin polymerization and structure. For mitochondrial calcium measurement cells were loaded with rhod 2-AM. We found that aggregate-prone mutations significantly decreased [Ca2+]mit, whereas non-aggregate-prone mutations did not decrease [Ca2+]mit. Moreover aggregate-prone desmin mutations resulted in increased resting cytosolic [Ca2+]. However this increase was not accompanied by any alterations in sarcoplasmic reticulum calcium release. We suggest that the observed decline in [Ca2+]mit was due to desmin aggregate accumulation resulting in the loss of desmin mitochondria interactions. © 2014 Elsevier Ltd.


Dmitrieva R.I.,Federal Almazov Medical Research Center | Revittser A.V.,Saint Petersburg State Polytechnic University | Klukina M.A.Maria A.,Federal Almazov Medical Research Center | Sviryaev Y.V.,Federal Almazov Medical Research Center | And 4 more authors.
Aging | Year: 2015

Background: Bone marrow multipotent mesenchymal stromal cells (BM-MMSC) considered as a prospective substrate for cell therapy applications, however adult stem cells could be affected by donor-specific factors: age, gender, medical history. Our aim was to investigate how HF affects the functional properties of BM-MMSC. Materials and methods: BM-MMSC from 10 healthy donors (HD), and 16 donors with chronic HF were evaluated for proliferative activity, ability to differentiate, replicative senescence, expression of genes that affect regeneration and fibrosis. The effect of culturing conditions on efficiency of BM-MMSC expansion was determined. Results: HF-derived BM-MMSC demonstrated early decrease of proliferative activity and upregulation of genes that control both, regeneration and fibrosis: Tgf-β pathway, synthesis of ECM, remodeling enzymes, adhesion molecules. We assume that these effects were related to increase of frequency of myofibroblast-like CD146+/SMAα+ CFU-F in HF samples; (ii) low seeding density and hypoxia resulted in predominant purification and expansion of CD146+/SMAα- CFU-Fs. (iii) the activity of NPs system was downregulated in HF BM-MMSC; Conclusions: downregulation of NP signaling in combination with upregulation of Tgf-β pathway in BM-MMSC would result in pro-fibrotic phenotype and make these cells non-effective for therapeutic applications; the corrections in culturing strategy resulted in 23-27 increase of expansion efficiency. © Dmitrieva et al.


Mitrofanova L.B.,Federal Almazov Medical Research Center | Gorshkov A.N.,Russian Academy of Sciences | Lebedev D.S.,Federal Almazov Medical Research Center | Mikhaylov E.N.,Federal Almazov Medical Research Center
PLoS ONE | Year: 2014

Background: There is a paucity of information on structural organization of muscular bundles in the interatrial septum (IAS). The aim was to investigate histologic and ultrastructural organization of muscular bundles in human IAS, including fossa ovalis (FO) and flap valve.Methods: Macroscopic and light microscopy evaluations of IAS were performed from postmortem studies of 40 patients. Twenty three IAS specimens underwent serial transverse sectioning, and 17 - longitudinal sectioning. The transverse sections from 10 patients were immunolabeled for HCN4, Caveolin3 and Connexin43. IAS specimens from 6 other patients underwent electron microscopy.Results: In all IAS specimens sections the FO, its rims and the flap valve had muscle fibers consisting of working cardiac myocytes. Besides the typical cardiomyocytes there were unusual cells: tortuous and horseshoe-shaped intertangled myocytes, small and large rounded myocytes with pale cytoplasm. The cells were aggregated in a definite structure in 38 (95%) cases, which was surrounded by fibro-fatty tissue. The height of the structure on transverse sections positively correlated with age (P = 0.03) and AF history (P = 0.045). Immunohistochemistry showed positive staining of the cells for HCN4 and Caveolin3. Electron microscopy identified cells with characteristics similar to electrical conduction cells.Conclusions: Specialized conduction cells in human IAS have been identified, specifically in the FO and its flap valve. The cells are aggregated in a structure, which is surrounded by fibrous and fatty tissue. Further investigations are warranted to explore electrophysiological characteristics of this structure. © 2014 Mitrofanova et al.


Nasredinov A.S.,Federal Almazov Medical Research Center | Lavreshin A.V.,Federal Almazov Medical Research Center
Genes and Cells | Year: 2014

Cell seeding is one of the most important stages in tissue engineering. Attempting to achieve fast, efficient and reliable result researchers in vascular tissue engineering use advantages of the tubular geometry of the grafts with conjunction of physical forces, such as pressure difference, centrifugal, electrostatic, magnetic forces and their combinations. This review describes the main trends and challenges in scaffold developing, main cellular types used for vascular tissue engineering and various methods for cell seeding, their advantages and drawbacks.


Mikhaylov E.N.,Federal Almazov Medical Research Center | Mitrofanova L.B.,Federal Almazov Medical Research Center | Vander M.A.,Federal Almazov Medical Research Center | Tatarskiy R.B.,Federal Almazov Medical Research Center | And 4 more authors.
Journal of Cardiovascular Electrophysiology | Year: 2015

Biatrial Reentry After Anterior LA Line Ablation Introduction A left atrial (LA) anterior ablation line (AnL), connecting the mitral annulus and right pulmonary veins or a roof line, has been suggested as an alternative to mitral isthmus (MI) ablation for perimitral flutter (PMF). Theoretically, the AnL can exclude the LA septal wall from the reentrant circle, and lead to involvement of the right atrium (RA) in a tachycardia (AT) mechanism. Methods and Results Among 807 patients undergoing atrial fibrillation ablation, PMF was diagnosed in 28 subjects, and AnL was performed in 13, and MI ablation in 15 cases. In 4 (31%) patients, AnL resulted in abrupt AT cycle length prolongation, which was associated with the development of a clockwise biatrial tachycardia (bi-AT). The bi-AT propagated along the lateral and posterior mitral annulus, entered the RA via the coronary sinus, and after activating the RA septum reentered the LA over the Bachmann's bundle. The bi-AT was terminated by ablation in Bachmann's bundle insertion areas in the RA or LA. No bi-AT was documented in the MI group. One patient in the AnL group died of stroke in 10 days following the procedure. Anatomic evaluation showed that at the level of the AnL the RA anteroseptal area was separated from the LA by the aortic root, and was free from ablation damage. Conclusion A bi-AT can develop when an AnL is created for PMF termination. Biatrial entrainment mapping facilitates diagnosis. Termination of the bi-AT is feasible when ablated from either RA or LA. © 2014 Wiley Periodicals, Inc.

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