34 research outputs found
Life safety culture as a pedagogical problem
It is well known that security is a necessary condition for the long-term development of humanity, society, the state and civilization as a whole, ensuring their stability and success. Currently, the Russian Federation pays close attention to the issues of educating the younger generation about a culture of life safety, which is supported by government initiatives, because ensuring the safety of the state citizens is among the priority components of a high standard of living. It is the culture of life safety that is defined as a component of the general culture of an individual and the main target for the activities of educational organizations. In this regard, the problem of the research is to substantiate the culture of life safety as a pedagogical category. The purpose of the research is to substantiate the content of the concept of ālife safety cultureā as a subject of pedagogical discourse and the basic target of the state educational policy. The methodological basis of the research is represented by the use of methods of analysis, theoretical generalization, and description.The results of the research are as follows: various approaches to the content of the concept of ālife safety cultureā as a pedagogical category have been analyzed; the structural components of safety culture have been identified; the target guidelines for instilling a life safety culture in educational institutions have been substantiated.Key conclusions: the issues of developing a culture of life safety among students have been considered in two contexts, as a necessary condition for the activities of teachers in developing the experience of safe behavior of students and as the creation of pedagogical conditions for a safe educational environment by all participants in educational activities. The target guidelines for instilling a culture of life safety among students are an integrated set of the following components: psychological, political, economic, environmental and information security of an individual
Species-specific differences in the Pro-Ala rich region of cardiac myosin binding protein-C
Cardiac myosin binding protein-C (cMyBP-C) is an accessory protein found in the A-bands of vertebrate sarcomeres and mutations in the cMyBP-C gene are a leading cause of familial hypertrophic cardiomyopathy. The regulatory functions of cMyBP-C have been attributed to the N-terminus of the protein, which is composed of tandem immunoglobulin (Ig)-like domains (C0, C1, and C2), a region rich in proline and alanine residues (the Pro-Ala rich region) that links C0 and C1, and a unique sequence referred to as the MyBP-C motif, or M-domain, that links C1 and C2. Recombinant proteins that contain various combinations of the N-terminal domains of cMyBP-C can activate actomyosin interactions in the absence of Ca2+, but the specific sequences required for these effects differ between species; the Pro-Ala region has been implicated in human cMyBP-C whereas the C1 and M-domains appear important in mouse cMyBP-C. To investigate whether species-specific differences in sequence can account for the observed differences in function, we compared sequences of the Pro-Ala rich region in cMyBP-C isoforms from different species. Here we report that the number of proline and alanine residues in the Pro-Ala rich region varies significantly between different species and that the number correlates directly with mammalian body size and inversely with heart rate. Thus, systematic sequence differences in the Pro-Ala rich region of cMyBP-C may contribute to observed functional differences in human versus mouse cMyBP-C isoforms and suggest that the Pro-Ala region may be important in matching contractile speed to cardiac function across species
Axial distribution of myosin binding protein-C is unaffected by mutations in human cardiac and skeletal muscle
Myosin binding protein-C (MyBP-C), a major thick filament associated sarcomeric protein, plays an important functional and structural role in regulating sarcomere assembly and crossbridge formation. Missing or aberrant MyBP-C proteins (both cardiac and skeletal) have been shown to cause both cardiac and skeletal myopathies, thereby emphasising its importance for the normal functioning of the sarcomere. Mutations in cardiac MyBP-C are a major cause of hypertrophic cardiomyopathy (HCM), while mutations in skeletal MyBP-C have been implicated in a disease of skeletal muscleādistal arthrogryposis type 1 (DA-1). Here we report the first detailed electron microscopy studies on human cardiac and skeletal tissues carrying MyBP-C gene mutations, using samples obtained from HCM and DA-1 patients. We have used established image averaging methods to identify and study the axial distribution of MyBP-C on the thick filament by averaging profile plots of the A-band of the sarcomere from electron micrographs of human cardiac and skeletal myopathy specimens. Due to the difficulty of obtaining normal human tissue, we compared the distribution to the A-band structure in normal frog skeletal, rat cardiac muscle and in cardiac muscle of MyBP-C-deficient mice. Very similar overall profile averages were obtained from the C-zones in cardiac HCM samples and skeletal DA-1 samples with MyBP-C gene mutations, suggesting that mutations in MyBP-C do not alter its mean axial distribution along the thick filament
Myosin binding protein C: implications for signal-transduction
Myosin binding protein C (MYBPC) is a crucial component of the sarcomere and an important regulator of muscle function. While mutations in different myosin binding protein C (MYBPC) genes are well known causes of various human diseases, such as hypertrophic (HCM) and dilated (DCM) forms of cardiomyopathy as well as skeletal muscular disorders, the underlying molecular mechanisms remain not well understood. A variety of MYBPC3 (cardiac isoform) mutations have been studied in great detail and several corresponding genetically altered mouse models have been generated. Most MYBPC3 mutations may cause haploinsufficiency and with it they may cause a primary increase in calcium sensitivity which is potentially able to explain major features observed in HCM patients such as the hypercontractile phenotype and the well known secondary effects such as myofibrillar disarray, fibrosis, myocardial hypertrophy and remodelling including arrhythmogenesis. However the presence of poison peptides in some cases cannot be fully excluded and most probably other mechanisms are also at play. Here we shall discuss MYBPC interacting proteins and possible pathways linked to cardiomyopathy and heart failure
Changes in cardiac contractility related to calcium-mediated changes in phosphorylation of myosin-binding protein C.
Ca ions can influence the contraction of cardiac muscle by activating kinases that specifically phosphorylate the myofibrillar proteins myosin-binding protein C (MyBP-C) and the regulatory light chain of myosin (RLC). To investigate the possible role of Ca-regulated phosphorylation of MyBP-C on contraction, isolated quiescent and rhythmically contracting cardiac trabeculae were exposed to different concentrations of extracellular Ca and then chemically skinned to clamp the contractile system. Maximum Ca-activated force (F(max)) was measured in quiescent cells soaking in 1) 2.5 mM Ca for 120 min, 2) 1.25 mM for 120 min, or 3) 1.25 mM for 120 min followed by 10 min in 7.5 mM, and 4) cells rhythmically contracting in 2.5 mM for 20 min. F(max) was, respectively, 21.5, 10.5, 24.7, and 32.6 mN/mm(2). Changes in F(max) were closely associated with changes in the degree of phosphorylation of MyBP-C and occurred at intracellular concentrations of Ca below levels associated with phosphorylation of RLC. Monophosphorylation of MyBP-C by a Ca-regulated kinase is necessary before beta-adrenergic stimulation can produce additional phosphorylation. These results suggest that Ca-dependent phosphorylation of MyBP-C modulates contractility by changing thick filament structure
Using the Experience of Japan in the Establishing of National Model of Economic Development of Ukraine
The article is aimed at studying the Japanese experience on formation and implementation of the national model of economic development and elaborating on its basis recommendations, which can be useful in the formation of domestic economic policy. It is specified that the system that is functioning in Japan enables the private sector and the Government to cooperate in order to reach common national ideas quickly and effectively. Unlike the Japanese practice, development of the national economy of Ukraine, and in particular international trade, is hampered by the imperfection of methods of the State regulation of the economy, and the underdeveloped market economy institutions. It is emphasized that the Government of Japan is interested in developing cooperation with our country in the sphere of trade, development of infrastructure, industry, agro-industrial complex, as well as energy-saving technologies. As a result of the analysis, the main vectors, which are based on the experience of Japan and should be guidelines to Ukraine, are disclosed
Multiple structures of thick filaments in resting cardiac muscle and their influence on cross-bridge interactions.
Based on two criteria, the tightness of packing of myosin rods within the backbone of the filament and the degree of order of the myosin heads, thick filaments isolated from a control group of rat hearts had three different structures. Two of the structures of thick filaments had ordered myosin heads and were distinguishable from each other by the difference in tightness of packing of the myosin rods. Depending on the packing, their structure has been called loose or tight. The third structure had narrow shafts and disordered myosin heads extending at different angles from the backbone. This structure has been called disordered. After phosphorylation of myosin-binding protein C (MyBP-C) with protein kinase A (PKA), almost all thick filaments exhibited the loose structure. Transitions from one structure to another in quiescent muscles were produced by changing the concentration of extracellular Ca. The probability of interaction between isolated thick and thin filaments in control, PKA-treated preparations, and preparations exposed to different Ca concentrations was estimated by electron microscopy. Interactions were more frequent with phosphorylated thick filaments having the loose structure than with either the tight or disordered structure. In view of the presence of MgATP and the absence of Ca, the interaction between the myosin heads and the thin filaments was most likely the weak attachment that precedes the force-generating steps in the cross-bridge cycle. These results suggest that phosphorylation of MyBP-C in cardiac thick filaments increases the probability of cross-bridges forming weak attachments to thin filaments in the absence of activation. This mechanism may modulate the number of cross-bridges generating force during activation
Neuroprotective properties of Na+/H+-exchanger isoform-1 inhibitor in experimental POAG
Introduction: Worldwide glaucoma is the leading cause of irreversible vision loss. The processes associated with the loss of retinal ganglion cells are multifactorial and have much in common with neurodegenerative diseases. Therefore the search for means to prevent the death of retinal neurons is an important task of modern pharmacology.
Materials and Methods: The study was conducted on male Wistar rats. Glaucoma was modeled by injecting a 1% solution of hyaluronic acid into the anterior chamber of the eye. The IOP level was recorded on the 0th, 63rd and 73rd days of the experiment. The effectiveness of the drugs was evaluated based on the results of ophthalmoscopy, electroretinography, followed by the determination of gene expression.
Results and Discussion: In the group with RU-1355 correction, the fundus picture improved; the index in the group was 18.0% lower compared to the model. The introduction of the RU-1355 compound provided an increase in the a-wave amplitude by 18.1%, and b-wave amplitude by 39.0% relative to the group with pathology. The most pronounced effect was observed on the expression level of BDNF, Bcl-2, Caspase 3 and NF-ĪŗB p65, which indicates that the compound has the capacity to influence the slowdown of the apoptosis process through an increase in the neurotrophic factor and the anti-apoptotic factor Bcl-2.
Conclusion: RU-1355 has neuroprotective properties, which was expressed by a decrease in ophthalmoscopic manifestations, preservation of the b-wave amplitude of the electroretinogram and the influence on gene expression of factors involved in apoptosis and neuroprotection. Based on the pharmacological activity of the RU-1355 compound in relation to POAG, further study of its action against other retinal diseases is promising