A method for evaluating the transport and energy conversion properties of polymer biomembranes using the Kedem-Katchalsky-Peusner equations.

BACKGROUND: A basic parameter in non-equilibrium thermodynamics is the production of entropy (S-entropy), which is a consequence of the irreversible processes of mass, charge, energy, and momentum transport in various systems. The product of S-entropy production and absolute temperature (T) is called the dissipation function and is a measure of energy dissipation in non-equilibrium processes. OBJECTIVES: This study aimed to estimate energy conversion in membrane transport processes of homogeneous non-electrolyte solutions. The stimulus version of the R, L, H, and P equations for the intensity of the entropy source achieved this purpose. MATERIAL AND METHODS: The transport parameters for aqueous glucose solutions through Nephrophan® and Ultra-Flo 145 dialyser® synthetic polymer biomembranes were experimentally determined. Kedem-Katchalsky-Peusner (KKP) formalism was used for binary solutions of non-electrolytes, with Peusner coefficients introduced. RESULTS: The R, L, H, and P versions of the equations for the S-energy dissipation were derived for the membrane systems based on the linear non-equilibrium Onsager and Peusner network thermodynamics. Using the equations for the S-energy and the energy conversion efficiency factor, equations for F-energy and U-energy were derived. The S-energy, F-energy and U-energy were calculated as functions of osmotic pressure difference using the equations obtained and presented as suitable graphs. CONCLUSIONS: The R, L, H, and P versions of the equations describing the dissipation function had the form of second-degree equations. Meanwhile, the S-energy characteristics had the form of second-degree curves located in the 1st and 2nd quadrants of the coordinate system. These findings indicate that the R, L, H, and P versions of S-energy, F-energy and U-energy are not equivalent for the Nephrophan® and Ultra-Flo 145 dialyser® membranes.

Evaluation of Transport Properties and Energy Conversion of Bacterial Cellulose Membrane Using Peusner Network Thermodynamics.

We evaluated the transport properties of a bacterial cellulose (BC) membrane for aqueous ethanol solutions. Using the Rr version of the Kedem-Katchalsky-Peusner formalism (KKP) for the concentration polarization (CP) conditions of solutions, the osmotic and diffusion fluxes as well as the membrane transport parameters were determined, such as the hydraulic permeability (Lp), reflection (σ), and solute permeability (ω). We used these parameters and the Peusner (Rijr) coefficients resulting from the KKP equations to assess the transport properties of the membrane based on the calculated dependence of the concentration coefficients: the resistance, coupling, and energy conversion efficiency for aqueous ethanol solutions. The transport properties of the membrane depended on the hydrodynamic conditions of the osmotic diffusion transport. The resistance coefficients R11r, R22r, and Rdetr were positive and higher, and the R12r coefficient was negative and lower under CP conditions (higher in convective than nonconvective states). The energy conversion was evaluated and fluxes were calculated for the U-, F-, and S-energy. It was found that the energy conversion was greater and the S-energy and F-energy were lower under CP conditions. The convection effect was negative, which means that convection movements were directed vertically upwards. Understanding the membrane transport properties and mechanisms could help to develop and improve the membrane technologies and techniques used in medicine and in water and wastewater treatment processes.

Modelling of the Electrical Membrane Potential for Concentration Polarization Conditions.

Based on Kedem-Katchalsky formalism, the model equation of the membrane potential (Δψs) generated in a membrane system was derived for the conditions of concentration polarization. In this system, a horizontally oriented electro-neutral biomembrane separates solutions of the same electrolytes at different concentrations. The consequence of concentration polarization is the creation, on both sides of the membrane, of concentration boundary layers. The basic equation of this model includes the unknown ratio of solution concentrations (Ci/Ce) at the membrane/concentration boundary layers. We present the calculation procedure (Ci/Ce) based on novel equations derived in the paper containing the transport parameters of the membrane (Lp, σ, and ω), solutions (ρ, ν), concentration boundary layer thicknesses (δl, δh), concentration Raileigh number (RC), concentration polarization factor (ζs), volume flux (Jv), mechanical pressure difference (ΔP), and ratio of known solution concentrations (Ch/Cl). From the resulting equation, Δψs was calculated for various combinations of the solution concentration ratio (Ch/Cl), the Rayleigh concentration number (RC), the concentration polarization coefficient (ζs), and the hydrostatic pressure difference (ΔP). Calculations were performed for a case where an aqueous NaCl solution with a fixed concentration of 1 mol m-3 (Cl) was on one side of the membrane and on the other side an aqueous NaCl solution with a concentration between 1 and 15 mol m-3 (Ch). It is shown that (Δψs) depends on the value of one of the factors (i.e., ΔP, Ch/Cl, RC and ζs) at a fixed value of the other three.

Energy conversion in Textus Bioactiv Ag membrane dressings using Peusner's network thermodynamic descriptions.

BACKGROUND: The Textus Bioactiv Ag membrane is an active dressing for the treatment of chronic wounds such as venous stasis ulcers and burns. OBJECTIVES: Determination of the transport and internal energy conversion properties of the Textus Bioactiv Ag membrane using the Kedem-Katchalsky-Peusner model. This model introduces the coefficients Lij necessary to calculate the degree of coupling (lij, QL), energy conversion efficiency (eij), dissipated energy (S-energy), free energy (F-energy), and internal energy (U-energy). MATERIAL AND METHODS: The research material was the Textus Bioactiv Ag membrane that is used as an active dressing in the treatment of difficult-to-heal wounds, and KCl aqueous solutions. The research methods employed Peusner's formalism of network thermodynamics and Kedem and Katchalsky's thermodynamics of membrane processes. To calculate the Lij coefficients, we used hydraulic conductivity (Lp), diffusion conductivity (u) and reflection (ó) coefficients to perform experimental measurements in different conditions. RESULTS: The Lp coefficient for the Textus Bioactiv Ag membrane is nonlinearly dependent on the average concentrations of the solutions. In turn, the u and ó coefficients are nonlinearly dependent on the differences in osmotic pressures (Äd). An increase in the Äd causes the Textus Bioactiv Ag membrane to become more permeable and less selective for KCl solutions. The coefficients of Peusner (Lij), couplings (lij, QL), energy conversion efficiency (eij), S-energy, F-energy, and U-energy also depend nonlinearly on Äd. Our results showed that for higher concentrations of KCl solutions transported through the Textus Bioactiv Ag membrane, the coupling and energy conversion coefficients were greater for larger Äd up to their maximum values for large Äd. Coupling of the membrane structure with the electrolyte flux through the membrane is observed for Äd greater than 10 kPa. CONCLUSIONS: Textus Bioactiv Ag membrane dressings possess the properties of a solution component separator as well as an internal energy converter.

Micro RNAs in Regulation of Cellular Redox Homeostasis.

In living cells Reactive Oxygen Species (ROS) participate in intra- and inter-cellular signaling and all cells contain specific systems that guard redox homeostasis. These systems contain both enzymes which may produce ROS such as NADPH-dependent and other oxidases or nitric oxide synthases, and ROS-neutralizing enzymes such as catalase, peroxiredoxins, thioredoxins, thioredoxin reductases, glutathione reductases, and many others. Most of the genes coding for these enzymes contain sequences targeted by micro RNAs (miRNAs), which are components of RNA-induced silencing complexes and play important roles in inhibiting translation of their targeted messenger RNAs (mRNAs). In this review we describe miRNAs that directly target and can influence enzymes responsible for scavenging of ROS and their possible role in cellular redox homeostasis. Regulation of antioxidant enzymes aims to adjust cells to survive in unstable oxidative environments; however, sometimes seemingly paradoxical phenomena appear where oxidative stress induces an increase in the levels of miRNAs which target genes which are supposed to neutralize ROS and therefore would be expected to decrease antioxidant levels. Here we show examples of such cellular behaviors and discuss the possible roles of miRNAs in redox regulatory circuits and further cell responses to stress.

[Network form of the Kedem-Katchalsky equations for ternary non-electrolyte solutions 7. Evaluation of Sij Peusner's coefficients for polymeric membrane]. / Sieciowa postac równan Kedem-Katchalsky'ego dla ternarnych roztworów nieelektrolitów. 7. Ocena wspólczynników Peusnera Sij membrany polimerowej.

BACKGROUND: Peusner's network thermodynamics (PNT) allows symmetrical and/or hybrid transformation of Kedem-Katchalsky (K-K) equations to network form. For homogenous solutions that consist of solvent and two soluble nonelec-metrolyte substances, there are two symmetrical and six hybrid forms of network K-K equations that contain symmetrical (Rij or Lij) or hybrid (Hij, Wij, Sij, Nij, Kij or Pij) Peusner coefficients. OBJECTIVES: The aim of this study is to introduce the hybrid form of network K-K equations that include tensor Peusner coefficients Sij (i, j ∈ {1, 2, 3}) for homogenous ternary solutions of nonelectrolytes and to calculate dependences of coefficients Sij on mean concentration of one solution component (C1) when the concentration of the other one is constant (C2). MATERIAL AND METHODS: The authors used celulose Nephrophan membrane of known transport parameters for aqueous glucose and ethanol solutions as a study material. The authors applied PNT formalism and K-K equations for ternary nonelectrotyle solutions as a study method. RESULTS: Hybrid network form of K-K equations was obtained for solutions that consist of a solvent and two dissolved non-electrolyte substances. Dependences of coefficients Sij (i, j ∈ {1, 2, 3}) on mean concentration of one solution component (C1) when the concentration of the other one is constant C2, were calculated for conditions of homogeneity of solutions. These calculations were done using experimentally determined coefficients of reflection (σ), hydraulic (Lp) and solute permeability (ω). CONCLUSIONS: Network form of K-K equations that include Peusner coefficients Sij (i, j ∈ {1, 2, 3}) constitutes a novel research tool to study membrane transport. We showed that coefficients S11, S12, S13, S21, S22, S23, S31, S32 and S33 were sensitive to alterations in concentration and composition of solutions separated by a polymer membrane.

[Evaluation of the Peusner's coefficients matrix for polymeric membrane and ternary non-electrolyte solutions]. / Ocena macierzy wspólczynników Peusnera membrany polimerowej i ternarnych roztworów nieelektrolitów.

BACKGROUND: A system of network forms of Kedem-Katchalsky (K-K) equations for ternary non-electrolyte solutions is made of eight matrix equations containing Peusner's coefficients R(ij), L(ij), H(ij), W(ij), K(ij), N(ij), S(ij) or P(ij) (i, j ∈ {1, 2, 3}). The equations are the result of symmetric or hybrid transformation of the classic form of K-K equations by the use of methods of Peusner's network thermodynamics (PNT). OBJECTIVES: Calculating concentration dependences of the determinant of Peusner's coefficients matrixes R(ij), L(ij), H(ij), W(ij), S(ij), N(ij), K(ij) and P(ij) (i, j ∈ {1, 2, 3}). MATERIAL AND METHODS: The material used in the experiment was a hemodialysis Nephrophan membrane with specified transport properties (L(p), σ, Ω) in aqueous glucose and ethanol solution. The method involved equations for determinants of the matrixes coefficients R(ij), L(ij), H(ij), W(ij), S(ij), N(ij), K(ij) or P(ij) (i, j ∈ {1, 2, 3}). RESULTS: The objective of calculations were dependences of determinants of Peusner's coeffcients matrixes R(ij), L(ij), H(ij), W(ij), S(ij), N(ij), K(ij) or P(ij) (i, j ∈ {1, 2, 3}) within the conditions of solution homogeneity upon an average concentration of one component of solution in the membrane (C1) with a determined value of the second component (C2). CONCLUSIONS: The method of calculating the determinants of Peusner's coeffcients matrixes R(ij), L(ij), H(ij), W(ij), S(ij), N(ij), K(ij) or P(ij) (i, j ∈ {1, 2, 3}) is a new tool that may be applicable in studies on membrane transport. Calculations showed that the coefficients are sensitive to concentration and composition of solutions separated by a polymeric membrane.

[Network form of the Kedem-Katchalsky equations for ternary non-electrolyte solutions. 8. evaluation of Pij Peusner's coefficients for polymeric membrane]. / Sieciowa postac równan Kedem-Katchalsky'ego dla ternarnych roztworów nieelektrolitów. 8. Ocena wspólczynników Peusnera Pij membrany polimerowej.

BACKGROUND: Methods of Peusner's network of thermodynamics (PNT) allow to obtain network forms of Kedem-Katchalsky (K-K) equations. The equations are the result of symmetric and/or hybrid transformation of the classic form of the K-K equations. For ternary non-electrolyte solutions, comprising a dissolvent and two solutions dissolved, the following network forms of the K-K equations may be obtained: two symmetric forms (containing Rij or Lij Peusner's coefficients) and six hybrid forms (containing Hij, Wij, Nij, Kij, Sij or Pij Peusner's coefficients). OBJECTIVES: Using the network form of the K-K equations for homogeneous ternary non-electrolyte solutions containing Pij (i, j ∈ {1, 2, 3}) Peusner's coefficients, the objective is to calculate concentration dependences Pij and compare them to concentration dependences of Sij (i, j ∈ {1, 2, 3}) coefficients, presented in the 7th part in this paper (Polim. Med. 2014, 44, 39-49). MATERIAL AND METHODS: In the experiment, a polymeric hemodialysis Nephrophan membrane with specified transport properties (Lp, σ, ω) was used for glucose solutions in aqueous ethanol. The method involves the PNT formalism and K-K equations for ternary non-electrolyte solutions. RESULTS: The objective of calculations were dependences of Pij Peusner's coeffcients and Pij/Sij (i, j ∈ {1, 2, 3}) quotients within the conditions of solution homogeneity upon an average concentration of one component of solution (C1) with a determined value of the second component (C2). CONCLUSIONS: The network form of K-K equations containing Peusner's coefficients Pij (i, j ∈ {1, 2, 3}) is a new tool that may be applicable in studies on membrane transport. Calculations showed that the coefficients are sensitive to concentration and composition of solutions separated by a polymeric membrane.

Generation of miRNA sponge constructs.

MicroRNA (miRNA) sponges are RNA molecules with repeated miRNA antisense sequences that can sequester miRNAs from their endogenous targets and thus serve as a decoy. Stably expressed miRNA sponges are especially valuable for long-term loss-of-function studies and can be used in vitro and in vivo. We describe here a straightforward method to generate retroviral miRNA sponge constructs using a single directional ligation reaction. This approach allows generation of sponges containing more than 20 miRNA binding sites. We provide a basis for the design of the sponge constructs with respect to the sequence of the miRNA binding site and the sequences flanking the miRNA binding sites. In-silico validation approaches are presented to test the predicted efficiencies of the sponges in comparison to known target genes. In addition, we describe in vitro validation experiments to confirm the effectiveness of the miRNA sponges. Finally, we describe how the here described procedure can be adapted to easily generate sponges that target multiple miRNAs simultaneously. In summary, our approach allows rapid generation of single or combination miRNA sponges that can be used for long-term miRNA loss-of-function studies.

[Network form of the Kedem-Katchalsky equations for ternary non-electrolyte solutions. 1. Evaluation of Rij Peusner's coefficients for polymeric membrane]. / Sieciowa postac równan Kedem-Katchalsky'ego dla ternarnych roztworów nieelektrolitów. 1. Ocena wspólczynników Peusnera Rij membrany polimerowej.

INTRODUCTION: Peusner's network thermodynamics (PNT) enables symmetrical or hybrid transformation of membrane transport equations. For Kedem-Katchalsky equations (K-K) these transformations create the network form of these equations that contain new types of coefficients which can be calculated from the experimentally determined transport parameters, such as hydraulic permeability coefficient (Lp), solute permeability (omega) and reflection (sigma). For ternary and homogeneous solutions of non-electrolytes, transformations result in two symmetrical and six hybrid K-K network equations. The symmetrical forms of K-K network equations contain Peusner's coefficients Rij or Lij, whereas hybrid forms of K-K network equations contain Peusner's coefficients Hij, Nij, Kij, Pij, Sij or Wij. PURPOSE: Derivation of network form of KK equations for homogeneous ternary solutions that contain nonelectrolytes Peusnera ratios Rij (i, j element of {1, 2, 3}) presented in the third-order matrix [R]. Evaluation of transport properties of the membrane using Peusner's coefficients Rij, the determinant of the matrix [R], somber elements belonging to Rij, quotients Rij/det [R] and quotients det [Rij]/det [R]. MATERIALS AND METHODS: A cellulose acetate hemodialysis membrane (Nephrophan) of known parameters for transport of aqueous glucose and ethanol solutions of was a research material. The PNT formalism and K-K equation for ternary nonelectrolyte solutions were a research tool in this paper. RESULTS: The network form of K-K equations for ternary solutions was presented, that was obtained using the symmetric transformation of Peusner's thermodynamic networks. The resulting equations were used to interpret the transport of nonelectrolytes solutions consisting of solvent and two solutes. We calculated dependences of Peusner's coefficients Rij (i, j element of { 1, 2, 3}) and det [R] from the average concentration of one component of solution in the membrane (C1) with a constant value of a second component (C2) in conditions of solutions homogeneity. We also calculated dependencies of minors belonging to the elements Rij, the quotients Rij/det [R] and quotients det [Rij]/det [R] on the average concentration of one component of solution in the membrane (C1) at a constant value of the second component (C2). CONCLUSION: Network form of K-K equations containing Peusner's coefficients Rij (i, j element of {1, 2, 3}) is a novel tool suitable for the examination of the membrane transport. The presented calculations showed that the values of coefficients R11, R21, R22, R23 and R13 are sensitive to the composition and concentration of the solutions separated by a polymer membrane.

[Network form of the Kedem-Katchalsky equations for ternary non-electrolyte solutions. 2. Evaluation of Lij Peusner's coefficients for polymeric membrane]. / Sieciowa postac równan Kedem-Katchalsky'ego dla ternarnych roztworów nieelektrolitów. 2. Ocena wspólczynników Peusnera Lij membrany polimerowej.

INTRODUCTION: Symmetrical or hybrid transformation of Kedem-Katchalsky membrane transport equations (K-K) can be performed using Peusner's network thermodynamics (PNT). For ternary and homogeneous solutions of non-electrolytes it result in two symmetrical and six hybrid network form of K-K equations. The symmetrical form of these equations contain Peusner's coefficients Rij or Lij, and hybrid form--Peusner's coefficients Hij, Nij, Kij, Pij, Sij or Wij. PURPOSE: Derivation of network form of K-K equations for homogeneous ternary non-electrolyte solutions containing Peusner's coefficients Lij (i, j element of {1, 2, 3}) creating a the third- order matrix of Peusner's coefficients [L] and the calculation of the Peusner's coefficients Lij and comparison these coefficients with coefficient Rij presented in the first part of the paper (Polim. Med.). MATERIALS AND METHODS: A cellulose acetate hemodialysis membrane (Nephrophan) with known parameters for the transport of aqueous solutions of glucose and ethanol was a research material. Our research method was the PNT formalism and K-K equation for ternary non-electrolyte solutions. RESULTS: The network form of K-K equations for ternary solution consisting of solvent and two dissolved substances was obtained. Dependences of Peusner's coefficients Lij (i, j element of {1, 2, 3}) on the average concentration of one component of solution in the membrane (C1) with a constant value of second component (C1) were calculated in the conditions of solution homogeneity. These coefficients can be calculated on the basis of based on experimentally determined transport parameters i.e. the hydraulic permeability coefficients (Lp), solute permeability (omega) and reflection (sigma). CONCLUSION: Network form of K-K equations containing Peusner's coefficients Lij (i, j element of {1, 2, 3}) can be used for examination of the membrane transport. The calculations showed that only coefficients L12, L22, L23 i L32 are sensitive to the concentration and composition of the solutions separated by the polymer membrane.

[Network form of the Kedem-Katchalsky equations for ternary non-electrolyte solutions. 3. Evaluation of Hij Peusner's coefficients for polymeric membrane]. / Sieciowa postac równan Kedem-Katchalsky'ego dla ternarnych roztworów nieelektrolitów. 3. Ocena wspólczynników Peusnera Hij membrany polimerowej.

INTRODUCTION: Using symmetrical or hybrid transformation Kedem-Katchalsky membrane transport equations (K-K) for ternary solutions can be transformed to symmetrical (Rij lub Lij) or hybrid (contain coefficients Hij, Wij, Sij, Nij, Kij or Pij) network form. PURPOSE: Derivation of network form of K-K equations for homogeneous ternary non-electrolyte solutions containing Peusner's coefficients Hij (i, j element of {1, 2, 3}) and calculation of these coefficients for solutions consisting of solvent and two dissolved substances. Moreover comparison of these coefficients with coefficients Rij and Lij presented in the first and second part of the paper (Polim. Med.) was shown. Coefficients Hij (i, j element of {1, 2, 3}) can be calculated on the basis of experimentally determined transport parameters i.e. the hydraulic permeability coefficients (Lp), solute permeability (omega) and reflection (sigma). MATERIALS AND METHODS: The research material was the membrane (Nephrophan) with known parameters for the transport of aqueous solutions of glucose and ethanol and the research tool was the formalism of Peusner's network thermodynamics (PNT) and K-K equation for ternary non-electrolyte solutions. RESULTS: Using the hybrid transformation of the Peusner's thermodynamic networks, the network form of K-K equations for ternary solution consisting of solvent and two dissolved substances was presented. Dependences of Peusner's coefficients Hij (i, j element of {1, 2, 3}) in the conditions of solutions homogeneity from the average concentration of one component of solution in the membrane (C1) with a constant value of second component (C2). CONCLUSION: Analysis of Peusner's coefficients Hij (i, j element of {1, 2, 3}) is a new tool, which can be used for examination of the membrane transport. The calculations proved, that the values of coefficients H12, H21, H22 and H32 are sensitive to the concentration and composition of the non-electrolyte solutions separated by the polymer membrane.

Evaluation the reflection coefficient of polymeric membrane in concentration polarization conditions.

INTRODUCTION: The reflection coefficient of the membrane (sigma) is one of the basic parameters of the polymer membrane transport. Classical methods used to determine this parameter require intensive mixing of two solutions separated by a membrane to eliminate the effects of concentration polarization. In the real conditions, especially in biological systems, this requirement is challenging. Thus, concentration boundary layers, which are the essence of the phenomenon of concentration polarization, form on both sides of the membrane. PURPOSE: The main aim of this paper is to determine whether the value of reflection coefficient in a concentration polarization conditions depend on the concentration of solutions and hydrodynamic state of concentration boundary layers. MATERIALS AND METHODS: In this paper, we used the hemodialysis membrane of cellulose acetate (Nephrophan) and aqueous glucose solutions as the research materials. Formalism of nonequilibrium thermodynamics and Kedem-Katchalsky equations were our research tools. RESULTS: Derived mathematical equations describe the ratio of reflection coefficients in a concentration polarization conditions (sigmaS) and in terms of homogeneity of the solutions (sigma). This ratio was calculated for the configuration in which the membrane was oriented horizontally. It was shown that each of the curves has a biffurcation point. Above this point, the value of the reflection coefficients depended on the concentration of the solution, the configuration of the membrane system and the hydrodynamic concentration boundary layers. Below this point, the system did not distinguish the gravitational directions. CONCLUSION: on coefficient of the hemodialysis membrane in a concentration polarization condition (sigmaS) is dependent on both the solutions concentration and the hydrodynamic state of the concentration boundary layers. The value of this coefficient is the largest in the state of forced convection, lower--in natural convection state and the lowest in diffusive state. Obtained equations may be relevant to the interpretation of membrane transport processes in conditions where the assumption of homogeneity of the solution is difficult to implement

[Network form of the Kedem-Katchalsky equations for ternary non-electrolyte solutions. 6. Evaluation of Kij Peusner's coefficients for polymeric membrane]. / Sieciowa postac równan Kedem-Katchalsky'ego dla ternarnych roztworów nieelektrolitów. 6. Ocena wspólczynników Peusnera Kij membrany polimerowej.

BACKGROUND: Peusner Network Thermodynamics (PNT) enables transformation of Kedem-Katchalsky (K-K) membrane transport equations from classical to network form. For ternary and homogenous nonelectrolyte solutions, transformation results in two symmetrical and six hybrid forms of network K-K equations. Symmetrical forms of these equations contain Peusner's coefficients Rij or Lij, whereas hybrid forms contain Peusner's coefficients Hij, Wij, Nij, Kij, Sij or Pij. Experimental transport parameters can be used to calculate Peusner's coefficients, i.e. hydraulic permeability (Lp), solute permeability (ω) and reflection (σ) parameters. OBJECTIVES: The aim of this paper is to derive network form of K-K equations for homogenous ternary nonelectrolyte solutions that contain Peusner's coefficients K ij (i, j ∈ {1, 2, 3}). These coefficients form a third degree matrix of Peusner's coefficients [K]. Moreover, we aim to calculate dependences of K ij coefficients on average concentration of one component of solution in a membrane (C1 ) when value of the second one (C2 ) is fixed and to compare these dependences with appropriate dependences for coefficients R ij , L ij , H ij and N ij presented in 1-5 parts of the paper. MATERIAL AND METHODS: A cellulose hemodialysis membrane (Nephrophan) of known transport parameters for aqueous glucose and ethanol solutions was a research material. The PNT formalism and classical form of K-K equations for ternary non-electrolyte solutions was a research tool in this paper. RESULTS: The network form of K-K equations was presented using the hybrid transformation of Peusner's thermodynamic networks for ternary solutions that contain solvent and two dissolved substances. For homogenous solutions, we calculated dependences of Peusner's coefficients Kij and quotients Kij/Rij, Kij/Lij, Kij/Hij and Kij/Nij (i, j ∈ {1, 2, 3}) on average concentration of one component (C1) of the solution in a membrane when value of the second one is fixed (C2). CONCLUSIONS: The network form of K-K equations that contain Peusner's coefficients Kij (i, j ∈ {1, 2, 3}) is a novel tool to study membrane transport. We showed based on calculations that coefficients K12, K21, K23 and K32 are sensitive for composition and concentration of solutions separated by a polymer membrane.

[Network form of the Kedem-Katchalsky equations for ternary non-electrolyte solutions. 5. Evaluation of Nij Peusner's coefficients for polymeric membrane]. / Sieciowa postac równan Kedem-Katchalsky'ego dla ternarnych roztworów nieelektrolitów. 5. Ocena wspólczynników Peusnera Nij membrany polimerowej.

BACKGROUND: Peusner Network Thermodynamics (PNT) enables symmetrical and/or hybrid transformation of classical Kedem-Katchalsky (K-K) equations to network forms. For homogenous nonelectrolyte solutions that consist of solvent and two dissolved substances, two symmetrical and six hybrid forms of network K-K equations can be obtained that contain symmetrical (Rij or Lij) or hybrid (Hij, Wij, Nij, Kij, Sij or Pij) Peusner's coefficients. OBJECTIVES: The aim of this paper is to derive network form of K-K equations for homogenous ternary nonelectrolyte solutions that contains Peusner's coefficients Nij (i, j ∈ {1, 2, 3}). These coefficients form a third degree matrix of Peusner's coefficients [N]. We also aim to calculate dependences of Nij coefficients on average concentration of one component of solution in a membrane (C1) when value of the second one (C2) is fixed and to compare these dependences with appropriate dependences for coefficients Rij, Lij, Hij and Wij presented in 1-4 parts of the paper. MATERIAL AND METHODS: A cellulose hemodialysis membrane (Nephrophan) of known transport parameters for aqueous glucose and ethanol solutions was a research material. The PNT formalism and classical form of K-K equations for ternary non-electrolyte solutions was a research tool in this paper. RESULTS: The network form of K-K equations was presented using the hybrid transformation of Peusner's thermodynamic networks for ternary solutions that contain solvent and two dissolved substances. For homogenous solutions, we calculated dependences of Peusner's coefficients Nij (i, j = 1, 2, 3) on average concentration of one component (C1) of the solution in a membrane when value of the second one is fixed (C2). Moreover, we calculated dependences of quotients Nij/Rij, Nij/Lij, Nij/Hij and Nij/Wij on average concentration of one component (C1) of the solution in a membrane when value of the second one is fixed (C2). CONCLUSIONS: The network form of K-K equations that contain Peusner's coefficients Nij (i, j ∈ {1, 2, 3}) is a novel tool to study membrane transport. Obtained results of calculations showed that coefficients N12, N21, N22 and N32 are sensitive for composition and concentration of solutions separated by a polymer membrane.

[Network form of the Kedem-Katchalsky equations for ternary non-electrolyte solutions. 4. Evaluation of Wij Peusner's coefficients for polymeric membrane]. / Sieciowa postac równan Kedem-Katchalsky'ego dla ternarnych roztworów nieelektrolitów. 4. Ocena wspólczynników Peusnera Wij membrany polimerowej.

BACKGROUND: Peusner Network Thermodynamics (PNT) enables symmetrical and/or hybrid transformation of classical Kedem-Katchalsky (K-K) equations to network forms. For homogenous nonelectrolyte solutions, two symmetrical and six hybrid forms of network K-K equations can be obtained that contain symmetrical (Rij or Lij) or hybrid (Hij, Wij, Nij, Kij, Sij or Pij) Peusner's coefficients. OBJECTIVES: The aim of this paper is to present network form of K-K equations for homogenous ternary nonelectrolyte solutions that contains Peusner's coefficients Wij (i, j ∈ {1, 2, 3}). We also aim to calculate dependences of Wij coefficients on average concentration of one component of solution in a membrane (C1) when value of the second one (C1) is fixed and to compare these dependences with appropriate dependences for coefficients Hij, Lij and Rij presented in 1-3 parts of the paper. MATERIAL AND METHODS: We used a cellulose hemodialysis membrane (Nephrophan) of known transport parameters for aqueous glucose and ethanol solutions as a research material. The PNT formalism and classical form of K-K equations for ternary non-electrolyte solutions was a research tool in this paper. RESULTS: The network form of K-K equations was presented for ternary solutions that contain solvent and two dissolved substances. For homogenous solutions, we calculated dependences of Peusner's coefficients Wij and quotients Wij/Hij, Wij/Lij and Wij/Rij (i, j ∈ {1, 2, 3}) on average concentration of one component (C1) of the solution in a membrane when value of the second one is fixed (C2). Calculations were made using experimentally determined coefficients of reflection (σ), hydraulic permeability (Lp) and solute permeability (ω). CONCLUSIONS: The network form of K-K equations that contain Peusner's coefficients Wij (i, j ∈ {1, 2, 3}) is a novel tool to study membrane transport. We showed that majority of the coefficients Wij and quotients Wij/Hij, Wij/Lij and Wij/Rij (i, j ∈ {1, 2, 3}) is sensitive for composition and concentration of solutions separated by a polymer membrane.

The Role of the Gravitational Field in Generating Electric Potentials in a Double-Membrane System for Concentration Polarization Conditions.

Electric potentials referred to as the gravielectric effect (∆ΨS) are generated in a double-membrane system containing identical polymer membranes set in horizontal planes and separating non-homogenous electrolyte solutions. The gravielectric effect depends on the concentration and composition of the solutions and is formed due to the gravitational field breaking the symmetry of membrane complexes/concentration boundary layers formed under concentration polarization conditions. As a part of the Kedem-Katchalsky formalism, a model of ion transport was developed, containing the transport parameters of membranes and solutions and taking into account hydrodynamic (convective) instabilities. The transition from non-convective to convective or vice versa can be controlled by a dimensionless concentration polarization factor or concentration Rayleigh number. Using the original measuring set, the time dependence of the membrane potentials was investigated. For steady states, the ∆ΨS was calculated and then the concentration characteristics of this effect were determined for aqueous solutions of NaCl and ethanol. The results obtained from the calculations based on the mathematical model of the gravitational effect are consistent with the experimental results within a 7% error range. It has been shown that a positive or negative gravielectric effect appeared when a density of the solution in the inter-membrane compartment was higher or lower than the density in the outer compartments. The values of the ∆ΨS were in a range from 0 to 27 mV. It was found that, the lower the concentration of solutions in the outer compartments of the two-membrane system (C0), for the same values of Cm/C0, the higher the ∆ΨS, which indicates control properties of the double-membrane system. The considered two-membrane electrochemical system is a source of electromotive force and functions as an electrochemical gravireceptor.

Cytotoxicity and Microbiological Properties of Copolymers Comprising Quaternary Ammonium Urethane-Dimethacrylates with Bisphenol A Glycerolate Dimethacrylate and Triethylene Glycol Dimethacrylate.

Using dental composite restorative materials with a copolymeric matrix chemically modified towards bioactive properties can help fight secondary caries. In this study, copolymers of 40 wt.% bisphenol A glycerolate dimethacrylate, 40 wt.% quaternary ammonium urethane-dimethacrylates (QAUDMA-m, where m represents 8, 10, 12, 14, 16 and 18 carbon atoms in the N-alkyl substituent), and 20 wt.% triethylene glycol dimethacrylate (BG:QAm:TEGs) were tested for (i) cytotoxicity on the L929 mouse fibroblast cell line; (ii) fungal adhesion, fungal growth inhibition zone, and fungicidal activity against C. albicans; and (iii) bactericidal activity against S. aureus and E. coli. BG:QAm:TEGs had no cytotoxic effects on L929 mouse fibroblasts because the reduction of cell viability was less than 30% compared to the control. BG:QAm:TEGs also showed antifungal activity. The number of fungal colonies on their surfaces depended on the water contact angle (WCA). The higher the WCA, the greater the scale of fungal adhesion. The fungal growth inhibition zone depended on the concentration of QA groups (xQA). The lower the xQA, the lower the inhibition zone. In addition, 25 mg/mL BG:QAm:TEGs suspensions in culture media showed fungicidal and bactericidal effects. In conclusion, BG:QAm:TEGs can be recognized as antimicrobial biomaterials with negligible biological patient risk.

MicroRNAs, macrocontrol: regulation of miRNA processing.

MicroRNAs (miRNAs) are a set of small, non-protein-coding RNAs that regulate gene expression at the post-transcriptional level. Maturation of miRNAs comprises several regulated steps resulting in approximately 22-nucleotide single-stranded mature miRNAs. Regulation of miRNA expression can occur both at the transcriptional level and at the post-transcriptional level during miRNA processing. Recent studies have elucidated specific aspects of the well-regulated nature of miRNA processing involving various regulatory proteins, editing of miRNA transcripts, and cellular location. In addition, single nucleotide polymorphisms in miRNA genes can also affect the processing efficiency of primary miRNA transcripts. In this review we present an overview of the currently known regulatory pathways of miRNA processing and provide a basis to understand how aberrant miRNA processing may arise and may be involved in pathophysiological conditions such as cancer.

Non-Coding RNAs in Cancer Radiosensitivity: MicroRNAs and lncRNAs as Regulators of Radiation-Induced Signaling Pathways.

Radiotherapy is a cancer treatment that applies high doses of ionizing radiation to induce cell death, mainly by triggering DNA double-strand breaks. The outcome of radiotherapy greatly depends on radiosensitivity of cancer cells, which is determined by multiple proteins and cellular processes. In this review, we summarize current knowledge on the role of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), in determining the response to radiation. Non-coding RNAs modulate ionizing radiation response by targeting key signaling pathways, including DNA damage repair, apoptosis, glycolysis, cell cycle arrest, and autophagy. Additionally, we indicate miRNAs and lncRNAs that upon overexpression or inhibition alter cellular radiosensitivity. Current data indicate the potential of using specific non-coding RNAs as modulators of cellular radiosensitivity to improve outcome of radiotherapy.