Vol 3, No 1 (2011)
- Year: 2011
- Published: 15.03.2011
- Articles: 15
- URL: https://actanaturae.ru/2075-8251/issue/view/854
Articles
Letter from the Editors
Acta Naturae. 2011;3(1):1-1
1-1
94 Steps to Success
Abstract
Without the use of specialized equipment, it is extremely difficult to achieve results in modern science. Unfortunately, the situation regarding scientific equipment in our country is far from perfect. This concerns not only the quality of instrumental resources in our research institutes and universities, but also the process of purchasing scientific equipment. The vice-chancellor of M.V. Lomonosov Moscow State University, Alexei Khokhlov, in an interview with Konstantin Kiselev, the director of the project Science and Technologies in the Russian Federation, speculates on this eternal problem of the Russian research and design sector.
Acta Naturae. 2011;3(1):6-10
6-10
BioBibliometry Statistics on life sciences publications
Abstract
Bibliometry is changing how science is organized . The count and examination of published works and references in research journals seem to be a magic wand that enables us to embrace the boundless, allowing us to capture in figures, talent, success and place, both in the history of science and of humanity.
Acta Naturae. 2011;3(1):11-17
11-17
The Cancer Genome: What's New?
Acta Naturae. 2011;3(1):18-19
18-19
Molecular and Physiological Mechanisms of Membrane Receptor Systems Functioning
Abstract
Molecular physiology is a new interdisciplinary field of knowledge that looks into how complicated biological systems function. The living cell is a relatively simple, but at the same time very sophisticated biological system. After the sequencing of the human genome, molecular physiology has endeavored to investigate the systems of cellular interactions at a completely new level based on knowledge of the spatial organization and functions of receptors, their ligands, and protein-protein interactions. In recent years, the achievements in molecular physiology have centered on the study of sensor reception mechanisms and intercellular data transfer, as well as the immune system physiology, amongst other processes.
Acta Naturae. 2011;3(1):20-28
20-28
Quantum Dots for Molecular Diagnostics of Tumors
Abstract
Semiconductor quantum dots (QDs) are a new class of fluorophores with unique physical and chemical properties, which allow to appreciably expand the possibilities for the current methods of fluorescent imaging and optical diagnostics. Here we discuss the prospects of QD application for molecular diagnostics of tumors ranging from cancer-specific marker detection on microplates to non-invasive tumor imaging in vivo. We also point out the essential problems that require resolution in order to clinically promote QD, and we indicate innovative approaches to oncology which are implementable using QD.
Acta Naturae. 2011;3(1):29-47
29-47
Assays for Detection of Telomerase Activity
Abstract
Progressive loss of the telomeric ends of chromosomes caused by the semi-conservative mechanism of DNA replication is an important timing mechanism which controls the number of cells doubling. Telomerase is an enzyme which elongates one chain of the telomeric DNA and compensates for its shortening during replication. Therefore, telomerase activity serves as a proliferation marker. Telomerase activity is not detected in most somatic cells, with the exception of embryonic tissues, stem cells, and reproductive organs. In most tumor cells (80-90%), telomerase is activated and plays the role of the main instrument that supports the telomere length, which can be used for the diagnostics of neoplastic transformation. This is the primary reason why assays regarding the development of telomerase activity have attracted the attention of researchers. Telomerase activity testing may be useful in the search for telomerase inhibitors, which have the potential to be anti-cancer drugs. Moreover, telomerase activation may play a positive role in tissue regeneration; e.g., after partial removal of the liver or cardiac infarction. All telomerase activity detection assays can be divided into two large groups: those based on direct detection of telomerase products, and those based on different systems of amplification of the signals from DNA that yield from telomerase. The methods discussed in this review are suitable for testing telomerase activity in different samples: in protozoa and mammalian cells, mixed cellular populations, and tissues.
Acta Naturae. 2011;3(1):48-68
48-68
Structural and Dynamic Study of the Transmembrane Domain of the Amyloid Precursor Protein
Abstract
Alzheimer’s disease affects people all over the world, regardless of nationality, gender or social status. An adequate study of the disease requires essential understanding of the molecular fundamentals of the pathogenesis. The amyloid β-peptide, which forms amyloid plaques in the brain of people with Alzheimer’s disease, is the product of sequential cleavage of a single-span membrane amyloid precursor protein (APP). More than half of the APP mutations found to be associated with familial forms of Alzheimer’s disease are located in its transmembrane domain. The pathogenic mutations presumably affect the structural-dynamic properties of the APP transmembrane domain by changing its conformational stability and/or lateral dimerization. In the present study, the structure and dynamics of the recombinant peptide corresponding to the APP fragment, Gln686-Lys726, which comprises the APP transmembrane domain with an adjacent N-terminal juxtamembrane sequence, were determined in the membrane mimetic environment composed of detergent micelles using NMR spectroscopy. The structure obtained in dodecylphosphocholine micelles consists of two α-helices: a short surface-associated juxtamembrane helix (Lys687-Asp694) and a long transmembrane helix (Gly700-Leu723), both connected via a mobile loop region. A minor bend of the transmembrane α-helix is observed near the paired residues Gly708-Gly709. A cholesterol-binding hydrophobic cavity is apparently formed under the loop region, where the juxtamembrane α-helix comes into contact with the membrane surface near the N-terminus of the transmembrane α-helix.
Acta Naturae. 2011;3(1):69-76
69-76
A In Vitro and In Vivo Study of the Ability of NOD1 Ligands to Activate the Transcriptional Factor NF-kB
Abstract
Pattern-recognition receptors (PRR) play a crucial role in the induction of the defense reactions of the immune system against pathogenic bacterial and viral infections. The activation of PRR by specific, highly conserved pathogen-associated molecular patterns (PAMPs) induces numerous immune reactions related both to innate and adaptive immunity. In addition to the well-studied Toll-like receptors, pathogens can be recognized by the receptors belonging to the other PRR families; including NOD-like receptors (NLR). Stimulation of members of NOD-like receptors (NOD1, 2) and Toll-like receptors results in the activation of the transcriptional factor NF-kB regulating gene expression in numerous molecules implicated in the development of proinflammatory reactions. As opposed to Toll-like receptors, the NF-kB-activating ability of NLRs has not been fully studied. In this work, we examine the ability of one member of the NLR family - NOD1 - to activate the main proinflammatory transcriptional factor NF-kB. We also compare the NF-kB-activating ability of NOD1 ligands of a different structure with TLR4,5 ligands in vitro and in vivo.
Acta Naturae. 2011;3(1):77-84
77-84
Family Analysis of Linkage and Association of HLA-DRB1, CTLA4, TGFB1, IL4, CCR5, RANTES, MMP9 and TIMP1 Gene Polymorphisms with Multiple Sclerosis
Abstract
Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system (CNS). Proteins of the immune system, as well as proteins that are involved in the infiltration of activated immune cells in the CNS, play an important role in the pathogenesis of MS. We investigated the association and linkage with MS of the following immune-system genes polymorphisms: HLA-DRB1, CTLA4, TGFB1, IL4, CCR5 and RANTES, as well as of the matrix metalloproteinase 9 (MMP9) and tissue inhibitor of metalloproteinase 1 (TIMP1) genes polymorphisms. For this purpose we used the transmission disequilibrium test (TDT). The group investigated was comprised of 100 nuclear families of Russian ethnicity, each consisting of an affected offspring and his nonaffected parents. It was found that HLA-DRB1*15 allele and MMP9*-1562C allele were transmitted from healthy heterozygous parents to affected children more frequently than alternative alleles (p = 0.02 and p = 0.04, respectively). Another family-based method, AFBAC (affected family-based control), showed MS association with HLA-DRB1*15, but not with the MMP9*-1562C allele.
Acta Naturae. 2011;3(1):85-92
85-92
Comparative Bioinformatic Analysis of Active Site Structures in Evolutionarily Remote Homologues of α,β-Hydrolase Superfamily Enzymes
Abstract
Comparative bioinformatic analysis is the cornerstone of the study of enzymes’ structure-function relationship. However, numerous enzymes that derive from a common ancestor and have undergone substantial functional alterations during natural selection appear not to have a sequence similarity acceptable for a statistically reliable comparative analysis. At the same time, their active site structures, in general, can be conserved, while other parts may largely differ. Therefore, it sounds both plausible and appealing to implement a comparative analysis of the most functionally important structural elements - the active site structures; that is, the amino acid residues involved in substrate binding and the catalytic mechanism. A computer algorithm has been developed to create a library of enzyme active site structures based on the use of the PDB database, together with programs of structural analysis and identification of functionally important amino acid residues and cavities in the enzyme structure. The proposed methodology has been used to compare some α,β-hydrolase superfamily enzymes. The insight has revealed a high structural similarity of catalytic site areas, including the conservative organization of a catalytic triad and oxyanion hole residues, despite the wide functional diversity among the remote homologues compared. The methodology can be used to compare the structural organization of the catalytic and substrate binding sites of various classes of enzymes, as well as study enzymes’ evolution and to create of a databank of enzyme active site structures.
Acta Naturae. 2011;3(1):93-98
93-98
Multi-walled Carbon Nanotubes Penetrate into Plant Cells and Affect the Growth of Onobrychis arenaria Seedlings
Abstract
Engineered nanoparticles (ENPs) are now being used in many sectors of industry; however, the impact of ENPs on the environment still requires further study, since their use, recycling, and accidental spill can result in the accumulation of nanoparticles in the atmosphere, soil, and water. Plants are an integral part of ecosystems; hence their interaction with ENPs is inevitable. It is important to understand the consequences of this interaction and assess its potential effects. The present research is focused on studying the effects of the industrial material Taunit, containing multi-walled carbon nanotubes (MWNTs), on plants, and testing of its ability to penetrate into plant cells and tissues. Taunit has been found to stimulate the growth of roots and stems and cause an increase in peroxidase activity in Onobrychis arenaria seedlings. Peroxidase activity increases with decreasing concentration of Taunit from 1,000 to 100 mg/l. MWNTs from Taunit were detected in the cells and tissues of seedling roots and leaves, implying the ability of MWNTs to penetrate into roots and accumulate there, as well as their ability to be transported into seedling leaves. Thus, the changes in the physiological parameters of plants are associated not only with MWNT adsorption on the root surface, as previously believed, but also with their penetration, uptake and accumulation in the plant cells and tissues.
Acta Naturae. 2011;3(1):99-106
99-106
Modeling Myocardial Infarction in Mice: Methodology, Monitoring, Pathomorphology
Abstract
Myocardial infarction is one of the most serious and widespread diseases in the world. In this work, a minimally invasive method for simulating myocardial infarction in mice is described in the Russian Federation for the very first time; the procedure is carried out by ligation of the coronary heart artery or by controlled electrocoagulation. As a part of the methodology, a series of anesthetic, microsurgical and revival protocols are designed, owing to which a decrease in the postoperational mortality from the initial 94.6 to 13.6% is achieved. ECG confirms the development of large-focal or surface myocardial infarction. Postmortal histological examination confirms the presence of necrosis foci in the heart muscles of 87.5% of animals. Altogether, the medical data allow us to conclude that an adequate mouse model for myocardial infarction was generated. A further study is focused on the standardization of the experimental procedure and the use of genetically modified mouse strains, with the purpose of finding the most efficient therapeutic approaches for this disease.
Acta Naturae. 2011;3(1):107-115
107-115
Association of Cytokine Gene Alleles with the Inflammation of Human Periodontal Tissue
Abstract
Gingivitis and periodontitis are chronic inflammatory diseases of the periodontal tissue in humans caused by both environmental and genetic factors. The human cytokine genes that regulate the immune response may play an important role in the development of these chronic inflammatory diseases. The aim of this study is to analyze the allele status of eight human cytokine genes and to associate it with the inflammation of periodontal tissue in humans. A total of 296 unrelated males of Russian origin were studied. A significant association of the IL1B and IL6 minor alleles and gingivitis was found. In addition, we found a significant association of the OHI-S index with the IL18 gene alleles. The influence of genetic factors on gingivitis may contribute to the understanding of the mechanisms of interaction between genetic and environmental factors in periodontal conditions, and to the identification of risk groups for effective prevention and treatment.
Acta Naturae. 2011;3(1):116-122
116-122
Guidelines for Authors
Acta Naturae. 2011;3(1):123-124
123-124