Erratum: Actin-binding protein alpha-actinin 4 (ACTN4) is a transcriptional co-activator of RelA/p65 sub-unit of NF-kB.

[This corrects the article DOI: 10.18632/oncotarget.901.

Matrix Metalloproteinases in Primary Culture of Cardiomyocytes.

The highly organized contractile apparatus of cardiomyocytes in heart tissue allows for their continuous contractility, whereas extracellular matrix components are synthesized and spatially organized by fibroblasts and endothelial cells. However, reorganization of the cardiomyocyte contractile apparatus occurs upon their 2D cultivation, which is accompanied by transient loss of their contractility and acquired capability of extracellular matrix synthesis (Bildyug, N. B.

EGF-induced dynamics of NF-κB and F-actin in A431 cells spread on fibronectin.

To evaluate the role of actin cytoskeleton in the regulation of NF-κB transcription factor, we analyzed its involvement in the intracellular transport and nuclear translocation of the NF-κB RelA/p65 subunit in A431 epithelial cells stimulated with fibronectin and EGF. Live cell imaging and confocal microscopy showed that EGF activated the movement of RelA/p65 in the cytoplasm. Upon cell adhesion to fibronectin, RelA/p65 concentrated onto stress fibers, and EGF stimulated its subsequent allocation to membrane ruffles, newly organized stress fibers, and discrete cytoplasmic actin-rich patches.

[Reorganization of actin cytoskeleton in the initial stage of transendothelial migration of bone marrow multipotent mesenchymal stromal cells].

The analysis of actin cytoskeleton reorganization in rat bone marrow multipotent mesenchymal stromal cells after one hour adhesion to a monolayer of endothelial cell line EA.hy 926 allowed us to identify three types of cells interacting with the endothelial cells. Approximately half of multipotent mesenchymal stromal cells retained a rounded shape, most of them contained large round actin aggregates, had irregular borders and contacted with the surface of the endothelial cells by microvilli or protrusions similar to small lamellae.

[Actin cytoskeleton organization and spreading of bone marrow stromal cells and cartilage cells during their combined and independent cultivation on different extracellular matrix proteins].

To clarify the mutual influence of bone marrow stromal cells (BMSCs) and cartilage cells we studied the organization of their actin cytoskeleton and cell spreading on different extracellular matrix proteins--laminin 2/4, collagen type I or fibronectin. It has been shown that the most pronounced difference in morphological characteristics of the cells such as their form, size and actin cytoskeleton organization occur in the case of interaction with fibronectin. So, after separate brief incubation of both cell types on fibronectin, the average area of BMSCs spreading was about 4 times greater than the area of the cartilage cell spreading.

[Contractile apparatus organization of cardiomyocytes upon their cultivation in collagen gels].

Cardiomyocytes are known to change their morphology and reorganize the contractile apparatus upon their culturing in 2D culture systems. Therefore, the monolayer cardiomyocyte cultures appear to be a poor model for studying of the biologically important processes in the heart. Present study relates to the searching for the most optimal culture conditions allowing cardiomyocytes to maintein their typical morphology and the native state of contractile apparatus.

[Filling the 3D scaffolds by the stromal bone marrow cells depends on the methods of cell seeding and the scaffold surface modifications].

The distribution of bone marrow stromal cells (BMSC) is studied in a 3D poly(L,L-lactide) scaffolds. It is shown that the population of cells seeding into the scaffold with a peristaltic pump (dynamic method) allows the penetration of cells inside of the scaffold compared with the application of the cell suspension on the scaffold surface (static method). In contrast to cells seeding to scaffold by dynamic method the cells seeding by static method migrate from scaffolds in the first few days almost completely.

Application of the skin and bone integrated pylon with titanium oxide nanotubes and seeded with dermal fibroblasts.

Background: Direct skeletal attachment of limb prostheses is associated with high rate of transcutaneous infection and loosening of the fixture in the medullary canal prompting for careful assessment of various means for enhancing the skin-device and bone-device interface. The skin and bone integrated pylon system constitutes a technological platform for different modifications being evaluated previously.

Objectives: The current study assessed the combination of nano-treatment skin and bone integrated pylon with its pre-seeding with dermal fibroblasts.

Two-stage implantation of the skin- and bone-integrated pylon seeded with autologous fibroblasts induced into osteoblast differentiation for direct skeletal attachment of limb prostheses.

Angio- and osteogenesis following the two-stage (TS) implantation of the skin- and bone-integrated pylon seeded with autologous fibroblasts was evaluated. Two consecutive animal substudies were undertaken: intramedullary subcutaneous implantation (15 rabbits) and a TS transcutaneous implantation (12 rabbits). We observed enhanced osseointegrative properties of the intramedullary porous component seeded with fibroblasts induced into osteoblast differentiation, as compared to the untreated porous titanium pylon.

[Efficacy of dermoplasty and the dermal equivalent in treatment of vast leg ulcers of mixed genesis].

The most frequent causes of leg ulcers (90-95%) are chronic venous insufficiency (45-60%), obliterating atherosclerosis of the lower extremity arteries (10-20%), diabetes mellitus (15-25%) and their combinations (10-15%). The leg ulcers, specified as pyoderma gangrenosum, are the rare and severe pathology, which is very often misdiagnosed. The case history of a 58-year old female patient with vast leg ulcers of the both shanks is analyzed.

Actin-binding protein alpha-actinin 4 (ACTN4) is a transcriptional co-activator of RelA/p65 sub-unit of NF-kB.

ACTN4 is an actin-binding protein that participates in cytoskeleton organisation. It resides both in the cytoplasm and nucleus and physically associates with various transcription factors. Here, we describe an effect of ACTN4 expression on transcriptional activity of the RelA/p65 subunit of NF-kB.

Functional compartmentalisation of NF-kB-associated proteins in A431 cells.

NF-kB proteins belong to a family of ubiquitous transcription factors involved in a number of cellular responses. While the pathways of NF-kB activation and input into the regulation of gene activity have been comprehensively investigated, its cytoplasmic functions are poorly understood. In this study we addressed effects of the compartmentalisation of NF-kB proteins RelA/p65 and p50 in relation to the inhibitor IkB-a, using fibronectin (FN) and epidermal growth factor (EGF) for environmental stimulation of epidermoid carcinoma A431 cells.

[Extracellular matrix dependence of the cardiomyocyte contractile apparatus organization].

In the process of cardiomyocyte culturing, their contractile apparatus undergoes reorganization involving the convertation of typical myofibrils into non-muscle type structures and subsequent restoration of the initial organization. The causes and mechanisms of the rearrangements described are unknown. In this study, we have shown that cultivation of cardiomyocytes on the individual extracellular matrix proteins, as well as on the matrix produced either by cardiac fibroblasts or by similar cardiomyocyte, reduses the time when the contractile apparatus is in a rearranged state, whereas soluble factors of the conditioned culture do not affect obviously these rearrangements.

[Migration rate of rabbit bone marrow stromal cells and rabbit dermal fibroblasts in different gels and activity of their MMPs].

This paper presents the results of the study of rabbit bone marrow stromal cells (BMSC) and rabbit dermal fibroblasts (DF) migration rates to collagen type I and fibrin gels. It has been shown that DF exhibit greater migration activity in collagen gel, whereas BMSC show a higher migration activity in fibrin gels. By studying the activity of matrix metalloproteinases (MMPs) synthesized by cells during cultivation in gels, it has been found for both cell types that the activity of MMP-9 is increased in fibrin gels and activity of MMP-2 is increased in collagen gels.

[Isolation of tropomyosin particles from the cytosol of cultured cells and their protein composition analysis].

The presence of actin-binding protein, tropomyosin, shaped as particles or protein complexes that have no bonds with actin structures were found while the analisys of structural rearrangements of actin cytoskeleton. However, their functioning is still unknown. To study the composition and properties of these protein complexes a novel method of their separation from the cells without destroying the structures of the cytoskeleton have been developed.

[Novel splicing isoform of actin-binding protein alpha-actinin 4 in epidermoid carcinoma cells A431].

Alpha-actinin 4 (ACTN4) belongs to actin binding proteins of the spectrin superfamily. Structural organisation of actin fibres and focal contacts is considered to be its primary function in a cell. Besides that, nucleocytoplasmic shuffling of ACTN4 and its involvement in nuclear processes were demonstrated.

[Effect of formaldehyde in low concentrations on the proliferation and organization of the cytoskeleton of cultured cells].

3-4% (1.07-1.42 M) formaldehyde is one of the most popular and well-known organs, tissues and cells fixer.

On the possible use of exogenous histones in cell technology.

The prospect of developing transport systems using histones for site-specific delivery of therapeutic agents that have poor penetration characteristics through cellular membranes and tissue barriers has been investigated. Histones immobilized on microspheres can also be used to modify surfaces intended for cell cultivation, facilitating adhesion, proliferation and network formation by interactions of cells through contacts with several microspheres. They can be applied to three-dimensional pore matrices that are designed for producing tissue-like structures in vitro.

[Stability of bone marrow stromal cells to low temperatures during differentiation].

On the bases of earlier conducted research about the stability of heterogeneous population of keratinocytes to low temperatures according to their stages of differentiation this experiment' studies in vitro the stability to low temperatures of rat bone marrow stromal cells before and after their adipocyte and osteocyte differentiation. Results show that bone marrow stromal cells after their differentiation into either adipocytes or octeocytes became least stable to low temperatures. Findings may serve as foundation for further studies that may explain the changes of processes and mechanisms that play a major role in BMSC stability to low temperatures according to their stage of differentiation.

[The effect of low temperatures on the viability of human epidermal keratinocytes found at different stages of differentiation].

The aim of this study was a comparative analysis to the degree of stability of human epidermal cells found at different stages of differentiation to low temperatures. The effect of different subzero temperatures of liquid nitrogen vapor on keratinocytes found both in human skin fragments and as isolated cells extracted from skin fragments has been studied. The degree of stability of epidermal cells low temperatures was evaluated by their ability to form a multilayer stratum in culture; hence this phenomenon explains the survival of a sufficient amount of proliferative cells after exposure to subzero temperatures.

[The cultivation of cells on the porous titanium implants with the different structure].

The data on human dermal fibroblasts and rabbit mesenchymal stromal cells cultivation on porous titanium implants are presented in given paper. Two types of implants were used: type 1--with irregular pores formed by pressed titanium particles and type 2--with regular pores formed by coalescence of one-size titanium particles into implant. The goal of this study was to choose the type of titanium implant porosity which ensures the tightest interaction of titanium implant with surrounding tissue cells after implantation in the body.

[Reconstruction of the connective tissue as a result of transplantation of fibrins dermal equivalent to the wounds of experimental animals].

We analyzed the effectiveness of wound healing in rats after application of the dermal equivalent (DE) based on fibrin with dermal fibroblasts. Histological studies of newly formed dermis biopsy samples selected during its recovery in the model wound in laboratory animals have shown a positive effect of DE on wound healing. It was found a significant increase in the area of collagen fibers, in the number of prekapillaries, capillaries and postcapillaries in the granulation tissue after application of DE compared with the control group, suggesting a more intense repair.

[Cells of coelomic liquid and cells of different tissues of sea star Asterias rubens L. isolated from intact and post-traumatic animals: behaviour and proliferation under cultivation in vitro].

Proposed sources of coelomocytes in Asteroidea after traumatic injures are coelomic epithelium, axial organ or Tidemann's bodies. To study the involvement of cell division in the process, proliferation of cells from different tissues of starfish Asterias rubens L. has been studied after bromdeoxyuridine incorporation in vivo.

Proteomic analysis of ACTN4-interacting proteins reveals it's a putative involvement in mRNA metabolism.

Alpha-actinin 4 (ACTN4) is an actin-binding protein. In the cytoplasm, ACTN4 participates in structural organisation of the cytoskeleton via cross-linking of actin filaments. Nuclear localisation of ACTN4 has also been reported, but no clear role in the nucleus has been established.

[Is "fibroblast" a specialized cell or a functional condition of mesenchymal cells derivatives?].

The debatable article is devoted to the analysis of consecutive changes of the notion about the origin, migration, morphofunctional heterogeneity, differentiation and proliferative potential of the basic cells of a connective tissue--fibroblasts. Despite of a plenty of an actual material on this section of cellular biology, till now there is no uniform concept about fibroblasts to a full degree defining their cytogenesis, features of phenotypic answers, and position in differon organization. In this article, the data available in literature are systematized and generalized.