Identifying the stability of housekeeping genes to be used for the quantitative real-time PCR normalization in retinal tissue of streptozotocin-induced diabetic rats

AIM:To investigate the stability of the seven housekeeping genes:beta-actin(ActB),glyceraldehyde-3-phosphate dehydrogenase(GAPDH),18s ribosomal unit 5(18s),cyclophilin A(CycA),hypoxanthine-guanine phosphoribosyl transferase(HPRT),ribosomal protein large P0(36B4)and terminal uridylyl transferase 1(U6)in the diabetic retinal tissue of rat model.METHODS:The expression of these seven genes in rat retinal tissues was determined using real-time quantitative reverse transcription polymerase chain reaction(RT-qPCR)in two groups;normal control rats and streptozotocininduced diabetic rats.The stability analysis of gene expression was investigated using geNorm,NormFinder,BestKeeper,and comparative delta-Ct(ΔCt)algorithms.RESULTS:The 36B4 gene was stably expressed in the retinal tissues of normal control animals;however,it was less stable in diabetic retinas.The 18s gene was expressed consistently in both normal control and diabetic rats’retinal tissue.That this gene was the best reference for data normalisation in RT-qPCR studies that used the retinal tissue of streptozotocin-induced diabetic rats.Furthermore,there was no ideal gene stably expressed for use in all experimental settings.CONCLUSION:Identifying relevant genes is a need for achieving RT-qPCR validity and reliability and must be appropriately achieved based on a specific experimental setting.

New solutions for old challenges in glaucoma treatment:is taurine an option to consider?

Glaucoma is a range of progressive optic neuropathies characterized by progressive retinal ganglion cell loss and visual field defects.It is recognized as a leading cause of irreversible blindness affecting more than 70 million people worldwide.Currently,reduction of intraocular pressure,a widely recognized risk factor for glaucoma development,is the only pharmacological strategy for slowing down retinal ganglion cell loss and disease progression.However,retinal ganglion cell death and visual field loss have been observed in normotensive glaucoma,suggesting that the disease process is partially independent of intraocular pressure.Taurine is one of the agents that have attracted attention of researchers recently.Taurine has been shown to be involved in multiple cellular functions,including a central role as a neurotransmitter,as a trophic factor in the central nervous system development,as an osmolyte,as a neuromodulator,and as a neuroprotectant.It also plays a role in the maintenance of the structural integrity of the membranes and in the regulation of calcium transport and homeostasis.Taurine is known to prevent N-methyl-D-aspartic acid-induced excitotoxic injury to retinal ganglion cells.A recently published study clearly demonstrated that taurine prevents retinal neuronal apoptosis both in vivo and in vitro.Protective effect of taurine may be attributed to direct inhibition of apoptosis,an activation of brain derived neurotrophic factor-related neuroprotective mechanisms and reduction of retinal oxidative and nitrosative stresses.Further studies are needed to fully explore the potential of taurine as a neuroprotective agent,so that it can be applied in clinical practice,particularly for the treatment of glaucoma.The objective of current review was to summarize recent evidence on neuroprotective properties of taurine in glaucoma.

Taurine protects against retinal and optic nerve damage induced by endothelin-1 in rats via antioxidant effects

Endothelin-1（ET-1）, a potent vasoconstrictor, is involved in retinal vascular dysregulation and oxidative stress in glaucomatous eyes. Taurine（TAU）, a naturally occurring free amino acid, is known for its neuroprotective and antioxidant properties. Hence, we evaluated its neuroprotective properties against ET-1 induced retinal and optic nerve damage. ET-1 was administered intravitreally to Sprague-Dawley rats and TAU was injected as pre-, co-or post-treatment. Animals were euthanized seven days post TAU injection. Retinae and optic nerve were examined for morphology, and were also processed for caspase-3 immunostaining. Retinal redox status was estimated by measuring retinal superoxide dismutase, catalase, glutathione, and malondialdehyde levels using enzyme-linked immuosorbent assay. Histopathological examination showed significantly improved retinal and optic nerve morphology in TAU-treated groups. Morphometric examination showed that TAU pre-treatment provided marked protection against ET-1 induced damage to retina and optic nerve. In accordance with the morphological observations, immunostaining for caspase showed a significantly lesser number of apoptotic retinal cells in the TAU pre-treatment group. The retinal oxidative stress was reduced in all TAU-treated groups, and particularly in the pre-treatment group. The findings suggest that treatment with TAU, particularly pre-treatment, prevents apoptosis of retinal cells induced by ET-1 and hence prevents the changes in the morphology of retina and optic nerve. The protective effect of TAU against ET-1 induced retinal and optic nerve damage is associated with reduced retinal oxidative stress.

Neuroprotective effects of exogenous brain-derived neurotrophic factor on amyloid-beta 1-40-induced retinal degeneration

Amyloid-beta(Aβ)-related alterations,similar to those found in the brains of patients with Alzheimer's disease,have been observed in the retina of patients with glaucoma.Decreased levels of brain-derived neurotrophic factor(BDNF)are believed to be associated with the neurotoxic effects of Aβpeptide.To investigate the mechanism underlying the neuroprotective effects of BDNF on Aβ_(1-40)-induced retinal injury in Sprague-Dawley rats,we treated rats by intravitreal administration of phosphate-buffered saline(control),Aβ_(1-40)(5 nM),or Aβ_(1-40)(5 nM)combined with BDNF(1μg/mL).We found that intravitreal administration of Aβ_(1-40)induced retinal ganglion cell apoptosis.Fluoro-Gold staining showed a significantly lower number of retinal ganglion cells in the Aβ_(1-40)group than in the control and BDNF groups.In the Aβ_(1-40)group,low number of RGCs was associated with increased caspase-3 expression and reduced TrkB and ERK1/2 expression.BDNF abolished Aβ_(1-40)-induced increase in the expression of caspase-3 at the gene and protein levels in the retina and upregulated TrkB and ERK1/2 expression.These findings suggest that treatment with BDNF prevents RGC apoptosis induced by Aβ_(1-40)by activating the BDNF-TrkB signaling pathway in rats.

Influence of shielding gas and non-consumable electrode configuration on weld formation

The effect of the shielding gas composition and the cathode processing history on the weld formation quality during welding with a non-consumable electrode at high current was studied. The major reasons for pores, “waists” and undercuts formation during welding at high currents and speed are discrete melt movement to the solidification front due to the arc decline from the cathode axis and significant melt overhanging in the pool tail part caused by excessive peak pressure on the discharge axis. Cathode flow dispersion causes the lack of displacement of the molten metal which results in its laminar flow in the weld pool, uniform flow of the metal to the crystallization front and sound weld formation. The melt movement in the weld pool and eventually the welded joint quality is determined by the pressure distribution pattern on the welded metal surface and the anode spot lag from the electrode. It was demonstrated that non-consumable electrode configurations that provide arcing with a diffuse cathode spot and increased helium concentration in the inert atmosphere during welding with a conical electrode allow sound weld formation.

Dose-dependent effects of NMDA on retinal and optic nerve morphology in rats

AIM: To investigate dose-dependent effects of N-methylD-aspartate(NMDA) on retinal and optic nerve morphology in rats.METHODS: Sprague Dawley rats, 180-250 g in weight were divided into four groups. Groups 1, 2, 3 and 4 were intravitreally administered with vehicle and NMDA at the doses 80, 160 and 320 nmol respectively. Seven days after injection, rats were euthanized, and their eyes were taken for optic nerve toluidine blue and retinal hematoxylin and eosin stainings. The TUNEL assay was done for detecting apoptotic cells.RESULTS: All groups treated with NMDA showed significantly reduced ganglion cell layer(GCL) thickness within inner retina, as compared to control group. Group NMDA 160 nmol showed a significantly greater GCL thickness than the group NMDA 320 nmol. Administration of NMDA also resulted in a dose-dependent decrease in the number of nuclei both per 100 μm GCL length and per 100 μm2 of GCL. Intravitreal NMDA injection caused dosedependent damage to the optic nerve. The degeneration of nerve fibres with increased clearing of cytoplasm was observed more prominently as the NMDA dose increased. In accordance with the results of retinal morphometry analysis and optic nerve grading, TUNEL staining demonstrated NMDA-induced excitotoxic retinal injury in a dose-dependent manner.CONCLUSION: Our results demonstrate dose-dependent effects of NMDA on retinal and optic nerve morphology in rats that may be attributed to differences in the severity of excitotoxicity and oxidative stress. Our results also suggest that care should be taken while making dose selections experimentally so that the choice might best uphold study objectives.

Magnesium acethyltaurate as a potential agent for retinal and optic nerve protection in glaucoma

Glaucoma is the second leading cause of irreversible vision impairment affecting more than 70 million people worldwide with approximately 10%suffering from glaucoma-related bilateral blind（Quigley and Broman,2006）.It is a multi-factorial disease that is characterized by optic nerve damage and visual field loss.Progressive loss of retinal ganglion cells（RGCs）resulting in visual field deficits is the hallmark of glaucoma.

Influence of the Magnetic Field on the Graphene Conductivity

The transversal conductivity of the gap-modification of the graphene was studied in the cases of weak nonquatizing and quantizing magnetic field. In the case of nonquantizing magnetic field the expression of the current density was derived from the Boltzmann equation. The dependence of conductivity and Hall conductivity on the magnetic field intensity was investigated. In the case of quantizing magnetic field the expression for the graphene transversal magnetoconductivity taking into account the scattering on the acoustic phonons was derived in the Born approximation. The graphene conductivity dependence on the magnetic field intensity was investigated. The graphene conductivity was shown to have the oscillations when the magnetic field intensity changes. The features of the Shubnikov-de Haas oscillations in graphene superlattice are discussed.

On the Optimal Modes of Controlled Transfer of Walking Propulsion Devices

The problem of walking machine leg transfer is considered.Optimal laws of transfer are determined with regard to geometrical features ofgroundand underwater.Complex optimality criterion is introduced as the sum of indexes of quality of the movement multiplied each by weight coefficients.The solution is provided based on the walking machine“Ortonog.”

Methodology of the Relationship between Bioethics, Philosophy, and Law

One can distinguish three levels in the integrative unity of knowledge and norms （assessments）, which is termed bioethics. The first level is theoretical. It is connected with the facts and truths. The second level deals with establishing of certain standards and rules of conduct, with the monitoring of their implementation and the assessment of the results of implementation/violation of norms. The third level is associated with individual behavior, formed on the basis of relevant knowledge （or lack of it, as is evident from the table）, and the rules governing its application. Theoretical Bioethics is an integral part of Philosophy---the practical Bioethics is directly related to Law and applied Bioethics deals with the personal standards of specific behavior in concrete situations. Social need for regulatory control of any activity with living entities has led to rapid development of practical Bioethics, while its philosophical content developed more slowly. This creates a conflict of norms and values, hampering the adoption of individual decisions now in the field of applied Bioethics. Deontologization of Bioethics can lead to the fact that it will lose its philosophical content and become a specific area of Law. This, in turn, leads to the dehumanization of Bioethics. It is therefore necessary to conduct a methodological analysis of the relationship of Philosophy, Bioethics and Law, the results of which will focus the researchers on the synchronization of the axiological, praxeological and ethical components of scientific research in order to preserve the intellectual integrity of Bioethics.

Synthesis and Properties of 1,3-bis-adamantyl Disubstituted Ureas and Biureas

1,3-disubstituted ureas of adamantine series are potent for hypertension and inflammatory treatment. The most valuable parameters of these compounds are melting point and solubility. Higher melting point leads to lower bioavailability and for most of the compounds investigated before it was very high. Usage of isocyanates containing 1,3-dimethyladamantane fragment will significantly decrease the melting point, improve solubility and therefore improve bioavailability of 1,3-disubstituted ureas and other biologically active compounds produced on its base. This article presents new 1,3-disubstituted ureas and biureas synthesized by the authors.

The Study on the Differential and Integral Calculus in Pseudoeuclidean Space

In the vector space of real vectors, comparison was executed of the multilinear forms, covariant derivatives, the total differentials and derivatives in the direction which are calculated with different metrics—with Euclidean metric and with pseudoeuclidean metric of a zero index. Comparison was executed of the Taylor’s formulas to different metrics. What is established by us is that multilinear forms of different metrics have different values;covariant derivatives have identical values;the total differentials and derivatives in the direction have different values. In Euclidean space, Taylor’s formula with any order of accuracy assigned in advance is equal, but in pseudoeuclidean space Taylor’s formula is not equal with any order of accuracy. It is concluded that in space with a pseudoeuclidean metric, the computing sense of the differential and integral calculus created in Euclidean space is lost and the possibility of mathematical model operation of real physical processes in vector space with pseudoeuclidean metric is called into question.

On the Role of the Entrostat in the Theory of Self-Organization

The reasons for introducing the concept of the entrostat in statistical physics are examined. The introduction of the entrostat has allowed researchers to show the possibility of self-organization in open systems within the understanding of entropy as a measure of disorder. The application of the laws written down for the entrostat has also allowed us to formulate the “synergetic open system” concept. A nonlinear model of the activity of a medium-sized company in the market is presented. In the course of the development of this model, the concept of the entrostat was used. This model includes the equation of a firm’s market activity and condition of its stability. It is shown that this stability depends on the income of the average buyers of the firm’s goods and furthermore that the equation estimating the firm’s market activity includes the scenario of a subharmonic cascade, which ends in chaos for the majority of market participants, i.e., in an economic crisis. The feature of this paper is that the decision containing the scenario of the subharmonic cascade is found analytically (instead of numerically, as is customary in the current scientific literature).

Restoration of Damaged Ecosystem Services on Wetlands in Northern Part of the Volga-Akhtuba Floodplain (Russia)

Due to the regulation of the river Volga flow, expanding of the territories intended for construction and development of agriculture wetlands Volga-Akhtuba floodplain are being significantly transformed and are losing many of their qualities. Non-regulated loads lead to the break of natural physical and chemical characteristics of water bodies, loss of biodiversity, degradation of structure and functions of biological communities and, as a result, to decreasing of potential ecosystem services. Restoration of the lost qualities of water ecosystems is a key factor in increasing sustainability of reclaimed landscapes and creating comfortable conditions for living of locals and their economic activity. On the territory of the biosphere reserve “Nature park” “Volga-Akhtuba floodplain” a number of model sites were defined in order for research projects and practical work on restoration of degraded landscapes to be executed. The widest range of the lost ecosystem qualities is being restored during work on Lake Zapornoye. Restoration of ecosystem functions is being implemented according to the main economic activities carried out in this area. Ecosystem services of the area are specified in accordance with its functional purpose. The existing landscape and ecology conditions have been studied and estimated to see if the planned ecosystem services can be provided. The project suggests the following activities: restoration of hydro-morphological characteristics, reconstruction of habitats for biodiversity and their ecosystem services, improvement to restore and preserve recreational qualities of landscape. The project includes the monitoring the effectiveness of restoration. Monitoring program is based on indices of environmental assessment.

The fundamental reasons for global catastrophes

This paper uses a new statistical method for studying self-organization in order to explain the origins of global catastrophes, namely the exceeding of the critical level of the planet’s organization. This method differs from traditional methods, because it uses specific notions such as the “entrostat” and “critical level of the organization of the open system”.

The Study on the Cycloids of Moving Loops

The infinite set of cycloids is created. Each cycloid of this set is defined as a movement trajectory of a point when this point circulates on the convex closed contour of arbitrary form when this contour moves rectilinearly without rotation on the plane with a velocity equal to the tangential velocity of a point on circulation contour. The classical cycloid is elements of this set. The differential equation of a cycloid set is derived and its solution in quadratures is received. The inverse problem when for the given cycloid it is necessary to fine the form of a circulation contour is solved. The problem of differential equation of the second order with boundary conditions about a bend of big curvature of an elastic rod of infinite length is solved in quadratures. Geometry of the loop which is formed at such bend is investigated. It is discovered that at movement of an elastic loop on a rod when the form and the size of a loop don’t change, each point of a loop moves on a trajectory which named by us the cycloid and which represents a circumference arch.

Increase in reproductive ability of high-producing cows, and qualitative parameters of their offspring, under conditions of intensive milk production

Objective: To study the methods of increasing the reproductive qualities and indices of viability in the offspring of Holstein cows under conditions of intensive milk production. Methods: Studies were conducted on 3 groups of Holstein cows with 30 heads in each group. Animals of the experimental groups had a different length physiological period. The study focused on experimental groups of animals: the reproductive indicators, the viability of newborn calves, and their growth rate. All the digital materials of the experimental data were processed by the method of variation statistics for the significance of the difference of the compared parameters using the Student's criterion, adopted in biology and zootechnics. Results: Studies found that reduction of the duration of the service period, along with a simultaneous increase in the inter-lactation period to 80–90 days, increased the reproductive capacity of the cows, and enhances the viability of the offspring compared with their peers. Conclusions: The study revealed the optimal duration of the physiological periods in high-producing cows under conditions of intensive milk production technology.

Amplification of a Few Cycle Optical Pulses in Graphene

This paper focuses on the propagation of a few cycle optical pulses in graphene in a case of electromagnetic field. Electrons in the quantum formalism were considered and a change of dispersion law with Coulomb repulsion was taken into account. The effective equation was numerically analyzed and an influence of Coulomb repulsion was found. The amplification of few cycle optical pulses in graphene with applying of electromagnetic field to our system was discovered. Results about the amplification of pulse in graphene have been achieved.

On Determining the Optimal Lifting Law of the Walking Propulsion Device Foot of an Underwater Robot from the Bottom

The problem of lifting the foot of the walking propulsion device of an underwater mobile robot is considered,taking into account the additional"compression""force acting on it.A mathematical model has been developed for the detachment of a propulsion foot from the ground,based on Henry's laws establishing the concentration of dissolved air in a liquid,the law of gas expansion at a constant temperature,Darcy's law on fluid filtration,and the theorem on the motion of the center of mass of a solid body.The linearized model allows to obtain and analytical solutions.Based on the solution of the variat ional problem,optimal modes of lifting the foot of the walking propulsion of an underwater mobile robot are established.