SIMULATION OF INFORMATION INFRASTRUCTURE FOR SMALL PEDAGOGICAL SYSTEM

The model of information infrastructure control for small pedagogical system including virtual machines is presented. Particular models of pedagogical system parameters are defined within the control model; the usage of risk model and application possibility of software technical quality model are justified. The key events (decision points) are highlighted in describing the life cycle of infrastructure control. The set of methods and algorithms supporting decision-making in the framework of a small pedagogical system is proposed. In order to illustrate the applicability of the generated solutions the main results of the experiments are presented

2-Deoxy-D-Glucose Treatment of Endothelial Cells Induces Autophagy by Reactive Oxygen Species-Mediated Activation of the AMP-Activated Protein Kinase

Autophagy is a cellular self-digestion process activated in response to stresses such as energy deprivation and oxidative stress. However, the mechanisms by which energy deprivation and oxidative stress trigger autophagy remain undefined. Here, we report that activation of AMP-activated protein kinase (AMPK) by mitochondria-derived reactive oxygen species (ROS) is required for autophagy in cultured endothelial cells. AMPK activity, ROS levels, and the markers of autophagy were monitored in confluent bovine aortic endothelial cells (BAEC) treated with the glycolysis blocker 2-deoxy-D-glucose (2-DG). Treatment of BAEC with 2-DG (5 mM) for 24 hours or with low concentrations of H2O2 (100 µM) induced autophagy, including increased conversion of microtubule-associated protein light chain 3 (LC3)-I to LC3-II, accumulation of GFP-tagged LC3 positive intracellular vacuoles, and increased fusion of autophagosomes with lysosomes. 2-DG-treatment also induced AMPK phosphorylation, which was blocked by either co-administration of two potent anti-oxidants (Tempol and N-Acetyl-L-cysteine) or overexpression of superoxide dismutase 1 or catalase in BAEC. Further, 2-DG-induced autophagy in BAEC was blocked by overexpressing catalase or siRNA-mediated knockdown of AMPK. Finally, pretreatment of BAEC with 2-DG increased endothelial cell viability after exposure to hypoxic stress. Thus, AMPK is required for ROS-triggered autophagy in endothelial cells, which increases endothelial cell survival in response to cell stress

Long-term exposure to hypoxia inhibits tumor progression of lung cancer in rats and mice

<p>Abstract</p> <p>Background</p> <p>Hypoxia has been identified as a major negative factor for tumor progression in clinical observations and in animal studies. However, the precise role of hypoxia in tumor progression has not been fully explained. In this study, we extensively investigated the effect of long-term exposure to hypoxia on tumor progression <it>in vivo.</it></p> <p>Methods</p> <p>Rats bearing transplanted tumors consisting of A549 human lung cancer cells (lung cancer tumor) were exposed to hypoxia for different durations and different levels of oxygen. The tumor growth and metastasis were evaluated. We also treated A549 lung cancer cells (A549 cells) with chronic hypoxia and then implanted the hypoxia-pretreated cancer cells into mice. The effect of exposure to hypoxia on metastasis of Lewis lung carcinoma in mice was also investigated.</p> <p>Results</p> <p>We found that long-term exposure to hypoxia a) significantly inhibited lung cancer tumor growth in xenograft and orthotopic models in rats, b) significantly reduced lymphatic metastasis of the lung cancer in rats and decreased lung metastasis of Lewis lung carcinoma in mice, c) reduced lung cancer cell proliferation and cell cycle progression <it>in vitro</it>, d) decreased growth of the tumors from hypoxia-pretreated A549 cells, e) decreased Na⁺-K⁺ATPase α1 expression in hypoxic lung cancer tumors, and f) increased expression of hypoxia inducible factors (HIF1α and HIF2α) but decreased microvessel density in the lung cancer tumors. In contrast to lung cancer, the growth of tumor from HCT116 human colon cancer cells (colon cancer tumor) was a) significantly enhanced in the same hypoxia conditions, accompanied by b) no significant change in expression of Na⁺-K⁺ATPase α1, c) increased HIF1α expression (no HIF2α was detected) and d) increased microvessel density in the tumor tissues.</p> <p>Conclusions</p> <p>This study demonstrated that long-term exposure to hypoxia repressed tumor progression of the lung cancer from A549 cells and that decreased expression of Na⁺-K⁺ATPase was involved in hypoxic inhibition of tumor progression. The results from this study provide new insights into the role of hypoxia in tumor progression and therapeutic strategies for cancer treatment.</p

Symbiotic Associations in the Phenotypically-Diverse Brown Alga Saccharina japonica

The brown alga Saccharina japonica (Areschoug) Lane, Mayes, Druehl et Saunders is a highly polymorphic representative of the family Laminariaceae, inhabiting the northwest Pacific region. We have obtained 16S rRNA sequence data in symbiont microorganisms of the typical form (TYP) of S. japonica and its common morphological varieties, known as “longipes” (LON) and “shallow-water” (SHA), which show contrasting bathymetric distribution and sharp morphological, life history traits, and ecological differences. Phylogenetic analysis of the 16S rRNA sequences shows that the microbial communities are significantly different in the three forms studied and consist of mosaic sets of common and form-specific bacterial lineages. The divergence in bacterial composition is substantial between the TYP and LON forms in spite of their high genetic similarity. The symbiont distribution in the S. japonica forms and in three other laminarialean species is not related to the depth or locality of the algae settlements. Combined with our previous results on symbiont associations in sea urchins and taking into account the highly specific character of bacteria-algae associations, we propose that the TYP and LON forms may represent incipient species passing through initial steps of reproductive isolation. We suggest that phenotype differences between genetically similar forms may be caused by host-symbiont interactions that may be a general feature of evolution in algae and other eukaryote organisms. Bacterial symbionts could serve as sensitive markers to distinguish genetically similar algae forms and also as possible growth-promoting inductors to increase algae productivity

INFORMATION INFRASTRUCTURE OF THE EDUCATIONAL ENVIRONMENT WITH VIRTUAL MACHINE TECHNOLOGY

Subject of research. Information infrastructure for the training environment with application of technology of virtual computers for small pedagogical systems (separate classes, author's courses) is created and investigated. Research technique. The life cycle model of information infrastructure for small pedagogical systems with usage of virtual computers in ARIS methodology is constructed. The technique of information infrastructure formation with virtual computers on the basis of process approach is offered. The model of an event chain in combination with the environment chart is used as the basic model. For each function of the event chain the necessary set of means of information and program support is defined. Technique application is illustrated on the example of information infrastructure design for the educational environment taking into account specific character of small pedagogical systems. Advantages of the designed information infrastructure are: the maximum usage of open or free components; the usage of standard protocols (mainly, HTTP and HTTPS); the maximum portability (application servers can be started up on any of widespread operating systems); uniform interface to management of various virtualization platforms, possibility of inventory of contents of the virtual computer without its start, flexible inventory management of the virtual computer by means of adjusted chains of rules. Approbation. Approbation of obtained results was carried out on the basis of training center "Institute of Informatics and Computer Facilities" (Tallinn, Estonia). Technique application within the course "Computer and Software Usage" gave the possibility to get half as much the number of refusals for components of the information infrastructure demanding intervention of the technical specialist, and also the time for elimination of such malfunctions. Besides, the pupils who have got broader experience with computer and software, showed better results within tests due to the usage of information infrastructure with virtual computers. Practical application. Obtained output can be recommended for introduction into the activity of educational institutions of secondary and higher education, and also for developing the author's and specialized courses focused on collective actions of pupils