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• Ginseng resist red blood cell oxidative stress via their "Qi-invigorating" effect. • Ginseng total saponins promote red blood cell membrane protein expression. • Ginseng total saponins improve energy metabolism of red blood cell. • Ginseng total saponins restore Band 3 protein function by inhibiting tyrosine phosphorylation. • Ginseng total saponins restore glycolysis by improving Band 3 protein function. Oxidative stress is the main cause of many diseases, but because of its complex pathogenic factors, there is no clear method for treating it. Ginseng total saponin (GTS) an important active ingredients in Panax ginseng C.A. Mey (PG) and has potential therapeutic ability for oxidative stress due to various causes. However, the molecular mechanism of GTS in the treating oxidative stress damage in red blood cells (RBCs) is still unclear. This study aimed to examine the protective effect of GTS on RBCs under oxidative stress damage and to determine its potential mechanism. The oxidative stress models of rat RBCs induced by hydrogen peroxide (H 2 O 2) and exhaustive swimming in vivo and in vitro was used. We determined the cell morphology, oxygen carrying capacity, apoptosis, antioxidant capacity, and energy metabolism of RBCs. The effect of tyrosine phosphorylation (pTyr) of Band 3 protein on RBCs glycolysis was also examined. GTS reduced the hemolysis of RBCs induced by H 2 O 2 at the lowest concentration. Moreover, GTS effectively improved the morphology, enhanced the oxygen carrying capacity, and increased antioxidant enzyme activity, adenosine triphosphate (ATP) levels, and adenosine triphosphatase (ATPase) activity in RBCs. GTS also promoted the expression of membrane proteins in RBCs, inhibited pTyr of Band 3 protein, and further improved glycolysis, restoring the morphological structure and physiological function of RBCs. This study shows, that GTS can protect RBCs from oxidative stress damage by improving RBCs morphology and physiological function. Changes in pTyr expression and its related pTyr regulatory enzymes before and after GTS treatment suggest that Band 3 protein is the main target of GTS in the treating endogenous and exogenous oxidative stress. Moreover, GTS can enhance the glycolytic ability of RBCs by inhibiting pTyr of Band 3 protein, thereby restoring the function of RBCs. [ABSTRACT FROM AUTHOR]

Highlights • A one-step anion-exchange chromatography method was developed to purify α-LA. • Highly pure α-LA (>90% based on total protein) was obtained (purification factor ∼8). • β-LG nearly 100% pure (based on the total protein content) was also obtained. • Purified α-LA samples were used to synthesise nanotubes from food-grade materials. • Fractions with contaminating proteins led to the formation of aggregates instead of nanotubes. Abstract A one-step anion-exchange chromatography method (NaCl gradient elution on a DEAE Sepharose™ Fast Flow gel column) was developed to purify α-lactalbumin (α-LA) from whey protein isolate. α-LA nearly 100% pure (based on the total protein content) was obtained with a yield of about 39%. Besides pure α-LA, which was the main objective of this work, highly pure β-lactoglobulin was also obtained with a yield of about 59%. The high purity of the obtained α-LA samples allowed its use to synthesise protein nanotubes with excellent gelation properties for their use as food thickeners and bioactive carriers. The samples' purity degree obtained (based on the total protein content) was critical in the formation of proper nanotubes instead of random aggregates, which produced opaque and weak gels, less useful for food applications. [ABSTRACT FROM AUTHOR]

Highlights • Selectivity of mixed-mode reversed-phase/weak-anion-exchange columns were evaluated. • RP and IEX retention mechanisms were investigated for different compound classes. • A novel model combining mixed-mode retention mechanisms was proposed and validated. Abstract The current study comprises a systematic investigation to assess retention properties and selectivity of a mixed-mode reversed-phase/weak-anion-exchange (RP/WAX) stationary phase to aid method development. Retention was investigated for different compound classes which vary in hydrophobicity, van der Waals surface area, and charge as function of organic content, pH, and ionic strength of the mobile phase. The linear-solvent-strength model was successfully applied for aromatic hydrocarbons to obtain retention-time predictions based on log P values and van der Waals surface area values. For phenols, predictions were based on log P values and data from a single scouting run performed in isocratic mode to estimate the S parameter; the deviations between experimental and predicted retention times were smaller than 6%. To describe the mixed-mode (RP/WAX) retention behavior of singly and doubly negatively-charged aromatic acids, a novel model combining the linear-solvent-strength and the empirical stoichiometric-displacement-net-charge models is proposed and validated. Using combinations of three scouting runs that are not linearly dependent, the maximum prediction error was 11% and changes in selectivity were correctly forecasted when altering the mobile-phase composition, i.e. , either organic modifier content or ionic strength. When using nine scouting runs in combination with a least-squares regression approach to determine the model parameters, the maximum prediction error was 6%. [ABSTRACT FROM AUTHOR]

Considering the performance of parent Fe(III)-Cu(II) binary oxide nanoparticles in removing numerous contaminants from water, in order to prevent the release of the nanostructures into the cleaned water a deposit with the same composition was introduced into the matrix of a synthetic porous material (ion exchange resin), whereby a hybrid ion exchanger (HIX) was obtained. Amberlite 900 Cl, a commercially available strongly basic macroreticular anion exchanger, was used as the supporting material. The inorganic deposit was introduced into its structure in two steps performed batchwise at ambient temperature. Fe(III)-Cu(II) binary oxide could be deposited into the matrix of the strongly basic anion exchanger owing to the affinity of its functional groups for FeCl 4 − and CuCl 4 2− ions. When in the ion exchange reaction the anion exchanger bound both the ions and the reaction medium alkalized, the respective oxides FeOOH and CuO precipitated in its structure. The oxide deposit was introduced into the ion exchanger in three ways, whereby HIXs differing in their oxide content, in the mole ratio of the oxides and in the latter's atypical distribution in the matrix of the anion exchanger were obtained. Regardless of the method of conducting the reaction, HIXs rich in oxides, e.g. 3.73 mmol (Fe, Cu) g −1 (2.35 mmol Fe and 1.38 mmol Cu g −1 at Fe/Cu = 1.7) were obtained. The products were investigated by SEM, EDXS, T/TG/DTA, XRD and VSM. The doped HIXs are characterized by a core-shell structure, where the core consists of polymeric beads and the outer thin layer contains Fe and Cu in their oxidized form. The structure of the outer layer varies depending on the procedure of precipitation. These differences are also reflected in the magnetic properties (ferromagnetic or paramagnetic interaction). CuFe 2 O 4 was found to be present in the samples sintered at 900 and 1300°C, which proves that a ferrite can form from the deposit after a solid-state reaction at high temperatures. [ABSTRACT FROM AUTHOR]

The Cu 2 Cr-DS-LDH hybrid was successfully prepared by the anion exchange method at room temperature. The structure, the chemical composition and the physico-chemical properties of the sample were determined using powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and inductively coupled plasma (ICP). In this work, the electrical and dielectric properties investigated are determined using impedance spectroscopy (IS) in a frequency range of 1 Hz to 1 MHz. Indeed, the Nyquist diagram modelized by an electrical equivalent circuit showed three contributions attributed respectively to the polarization of grains, grains boundaries and interface electrode-sample. This modelization allowed us to determine the intrinsic electrical parameters of the hybrid (resistance, pseudo-capacitance and relaxation time). The presence of the non-Debye relaxation phenomena was confirmed by the frequency analysis of impedance. Moreover, the evolution of the alternating current conductivity ( σ ac ) studied obeys the double power law of Jonscher. The ionic conduction of this material was generated through a jump movement by translation of the charge carriers. As for the dielectric behavior of the material, the evolution of dielectric constant as a function of frequency shows relatively high values in a frequency range between 10 Hz and 1 KHz. The low values of the loss tangent obtained in this frequency zone can valorize this LDH hybrid. [ABSTRACT FROM AUTHOR]

Synthesis of nanoparticles is an enzymatic reduction process in microorganisms. In the present study, a protein, lignin peroxidase has been purified by DEAE-Cellulose anion exchange chromatography and Biogel P-150 gel filtration chromatography from the cell suspension of Acinetobacter sp. SW30 responsible for the synthesis of gold nanoparticles (AuNP) and selenium nanoparticles (SeNP). The purified fraction has a specific activity of 29.4 U/mg/min with 959 fold purification. Native and SDS PAGE confirmed that purified lignin peroxidase is monomeric enzyme with 97.4 KDa molecular weight. The enzyme synthesized spherical crystalline AuNP (10 ± 2 nm) and amorphous SeNP (100 ± 10 nm). It has maximum activity at pH 2 and temperature 40 °C, with 1.0 mM Km value, when n -propanol was used as a substrate. Activity was completely inhibited by sodium thiosulphate and zinc sulphate. This is the first report on association of lignin peroxidase in the synthesis of AuNP and SeNP from Acinetobacter sp. SW30. [ABSTRACT FROM AUTHOR]

Summary Anion exchanger 1 (AE1) is a critical transporter and the primary structural scaffold for large macromolecular complexes responsible for erythrocyte membrane flexibility and integrity. We used zero-length crosslinking and mass spectrometry to probe AE1 structures and interactions in intact erythrocyte membranes. An experimentally verified full-length model of AE1 dimers was developed by combining crosslink-defined distance constraints with homology modeling. Previously unresolved cytoplasmic loops in the AE1 C-terminal domain are packed at the domain-domain interface on the cytoplasmic face of the membrane where they anchor the N-terminal domain's location and prevent it from occluding the ion channel. Crosslinks between AE1 dimers and ankyrin-1 indicate the likely topology for AE1 tetramers and suggest that ankyrin-1 wraps around AE1 tetramers, which may stabilize this oligomer state. This interaction and interactions of AE1 with other major erythrocyte membrane proteins show that protein-protein contacts are often substantially more extensive than previously reported. [ABSTRACT FROM AUTHOR]

AMP18 is a stomach-specific secreted protein expressed in normal gastric mucosa but absent in gastric cancer. AMP18 plays a major role in maintaining gastric mucosa integrity and is characterized by the presence of a BRICHOS domain consisting of about 100 amino acids, present also in several unrelated proteins, and probably endowed with a chaperon-like activity. In this work, we exploited a functional proteomic strategy to identify potential AMP18 interactors with the aim to add knowledge on its functional role within gastric cell lines and tissues. To this purpose, recombinant biotinylated AMP18 was purified and incubated with protein extract from human normal gastric mucosa by applying an affinity chromatography strategy. The interacting proteins were identified by peptide mass fingerprinting using MALDI-TOF mass spectrometry. The pool of interacting proteins contained SLC26A3, a protein expressed in the apical membrane of intestinal epithelial cells, supposed to play a critical role in Cl − absorption and fluid homeostasis. The interaction was also confirmed by Western blot with anti-SLC26A3 on transfected AGS cell extract following AMP18 pull-down. Furthermore, the interaction between AMP18 and SLC26A3 was also validated by confocal microscopy that showed a co-localization of both proteins at plasma membrane level. More importantly, for the first time, we showed that SLC26A3 is down-regulated in gastric cancer and that the overexpression of AMP18 in AMP-transfected gastric cancer cells up-regulated the expression of SLC26A3 both at transcriptional and translational level, the latter probably through the activation of the MAP kinases pathway. These findings strongly suggest that AMP18 might play an anti-inflammatory role in maintaining mucosal integrity also by regulating SLC26A3 level. [ABSTRACT FROM AUTHOR]

We determined the role of chloride--bicarbonate anion exchanger 3 in formalin-induced acute and chronic rat nociception. Formalin (1%) produced acute (first phase) and tonic (second phase) nociceptive behaviors (flinching and licking/lifting) followed by long-lasting evoked secondary mechanical allodynia and hyperalgesia in both paws. Local peripheral pre-treatment with the chloride--bicarbonate anion exchanger inhibitors 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid and 4-acetamido-4'-isothiocyanato-2,2'-stilbenedisulfonic acid prevented formalin-induced nociception mainly during phase 2. These drugs also prevented in a dose-dependent fashion long-lasting evoked secondary mechanical allodynia and hyperalgesia in both paws. Furthermore, post-treatment (on day 1 or 6) with 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid reversed established hypersensitivity. Anion exchanger 3 was expressed in dorsal root ganglion neurons and it co-localized with neuronal nuclei protein (NeuN), substance P and purinergic P2X3 receptors. Furthermore, Western blot analysis revealed a band of about 85 kDa indicative of anion exchanger 3 protein expression in dorsal root ganglia of naïve rats, which was enhanced at 1 and 6 days after 1% formalin injection. On the other hand, this rise failed to occur during 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid exposure. These results suggest that anion exchanger 3 is present in dorsal root ganglia and participates in the development and maintenance of short and long-lasting formalin-induced nociception. [ABSTRACT FROM AUTHOR]

The anion exchanger 1 (AE1), a member of bicarbonate transporter family SLC4, mediates an electroneutral chloride/bicarbonate exchange in physiological conditions. However, some point mutations in AE1 membrane-spanning domain convert the electroneutral anion exchanger into a Na+ and K+ conductance or induce a cation leak in a still functional anion exchanger. The molecular determinants that govern ion movement through this transporter are still unknown. The present study was intended to identify the ion translocation pathway within AE1. In the absence of a resolutive three-dimensional structure of AE1 membrane-spanning domain, in silico modeling combined with site-directed mutagenesis experiments was done. A structural model of AE1membrane-spanning domain is proposed, and this model is based on the structure of a uracil-proton symporter. This model was used to design cysteine-scanning mutagenesis on transmembrane (TM) segments 3 and 5. By measuring AE1 anion exchange activity or cation leak, it is proposed that there is a unique transport site comprising TM3-5 and TM8 that should function as an anion exchanger and a cation leak. [ABSTRACT FROM AUTHOR]

Abstract: Despite their curious morphology prompting numerous hypotheses of their normal function, the root cells lining the cochlear outer sulcus have long evaded physiological characterization. A growing body of evidence now suggests that they regulate the solute content of the endolymph and/or the perilymph, and may be essential in safe-guarding the global homeostasis of the cochlea. Immuno-labeling experiments have demonstrated polarized expression of key ion transport proteins, and recent electrophysiological recordings have identified specific membrane conductances. These studies have painted a clearer picture of how this unusual cell type may contribute to the maintenance of sound transduction, and how they may be central to pathological processes associated with various forms of hearing loss. This article is part of a Special Issue entitled “Annual Reviews 2013”. [Copyright &y& Elsevier]

Abstract: The present study was aimed at investigating the effect of fullerenol C60(OH)36 on chosen parameters of the human erythrocyte membrane and the preliminary estimation of the properties of fullerenol as a potential linking agent transferring the compounds (e.g., anticancer drugs) into the membrane of erythrocytes. The results obtained in this study confirm the impact of fullerenol on erythrocyte cytoskeletal transmembrane proteins, particularly on the band 3 protein. The presence of fullerenol in each of the concentrations used prevented degradation of the band 3 protein. The results show that changes in the morphology of red blood cells caused by high concentrations of fullerenol (up to 150mg/L) did not lead to increased red blood cell hemolysis or the leakage of potassium. Moreover, fullerenol slightly prevented hemolysis and potassium efflux. The protective effect of fullerenol at the concentration of 150mg/L was 20.3%, and similar results were obtained for the efflux of potassium. The study shows that fullerenol slightly changed the morphology of the cells and, therefore, altered the intracellular organization of erythrocytes through the association with cytoskeletal proteins. [Copyright &y& Elsevier]

Protein export from the endoplasmic reticulum (ER) depends on the interaction between a signal motif on the cargo and a cargo recognition site on the coatomer protein complex II. A hydrophobic sequence in the N terminus of the bovine anion exchanger 1 (AE1) anion exchanger facilitated the ER export of human AE1Δ11, an ER-retained AE1 mutant, through interaction with a specific Sec24 isoform. The cell surface expression and N-glycan processing of various substitution mutants or chimeras of human and bovine AE1 proteins and their Δ11 mutants in HEK293 cells were examined. The N-terminal sequence (V/L/F)X(I/L)X(M/L), 26VSIPM30 in bovine AE1, which is comparable with ΦXΦXΦ, acted as the ER export signal for AE1 and AE1Δ11 (Φis a hydrophobic amino acid, and X is any amino acid). The AE1-Ly49E chimeric protein possessing the ΦXΦXΦ motif exhibited effective cell surface expression and N-glycan maturation via the coatomer protein complex II pathway, whereas a chimera lacking this motif was retained in the ER. A synthetic polypeptide containing the N terminus of bovine AE1 bound the Sec23A-Sec24C complex through a selective interaction with Sec24C. Co-transfection of Sec24C-AAA, in which the residues 895LIL897 (the binding site for another ER export signal motif IXM on Sec24C and Sec24D) were mutated to 895AAA897, specifically increased ER retention of the AE1-Ly49E chimera. These findings demonstrate that the ΦXΦXΦsequence functions as a novel signal motif for the ER export of cargo proteins through an exclusive interaction with Sec24C. [ABSTRACT FROM AUTHOR]

Abstract: Band 3 (B3), the anion transporter, is an integral membrane protein that plays a key structural role by anchoring the plasma membrane to the spectrin-based membrane skeleton in the red cell. In addition, it also plays a critical role in the assembly of glycolytic enzymes to regulate red cell metabolism. However, its ability to recruit proteins that can prevent membrane oxidation has not been previously explored. In this study, using a variety of experimental approaches including cross-linking studies, fluorescence and dichroic measurements, surface plasmon resonance analysis, and proteolytic digestion assays, we document that the antioxidant protein peroxiredoxin-2 (PRDX2), the third most abundant cytoplasmic protein in RBCs, interacts with the cytoplasmic domain of B3. The surface electrostatic potential analysis and stoichiometry measurements revealed that the N-terminal peptide of B3 is involved in the interaction. PRDX2 underwent a conformational change upon its binding to B3 without losing its peroxidase activity. Hemichrome formation induced by phenylhydrazine of RBCs prevented membrane association of PRDX2, implying overlapping binding sites. Documentation of the absence of binding of PRDX2 to B3 Neapolis red cell membranes, in which the initial N-terminal 11 amino acids are deleted, enabled us to conclude that PRDX2 binds to the N-terminal cytoplasmic domain of B3 and that the first 11 amino acids of this domain are crucial for PRDX2 membrane association in intact RBCs. These findings imply yet another important role for B3 in regulating red cell membrane function. [Copyright &y& Elsevier]

Abstract: Chitosan is employed as an absorption enhancer for drug delivery strategies. Aim of this study was to investigate the rapid effects on barrier properties of the intestinal epithelial cell model HT-29/B6. Chitosan (0.005%) induced a fast decrease in transepithelial resistance (Rt) which was completely reversible after wash-out. Two-path impedance spectroscopy revealed that chitosan affects both, the paracellular (Rpara) and the transcellular (Rtrans) resistance. pH-dependence and inhibition of both effects by negatively charged heparin indicated a chitosan action only in the protonated form. The decrease in Rtrans was mediated by activation of a chloride-bicarbonate exchanger involved in intracellular pH regulation. This activation was coupled to the decrease in Rpara which was associated with an increase in ion permeability and permeability for paracellular flux markers up to 10 kDa. No effects on expression and subcellular distribution of tight junction (TJ) proteins or the actin cytoskeleton were observed. Accordingly, inhibition of actin–myosin interaction, Ca2+-dependent intracellular signaling, PKC, PI3K/Akt, MAP kinase p38, and endocytosis pathways did not impair the chitosan effect. These results suggest that the rapid and reversible absorption-enhancing chitosan effect is due to changes in intracellular pH caused by the activation of a chloride-bicarbonate exchanger resulting in the opening of the TJ. [Copyright &y& Elsevier]

Abstract: In our previous paper, we demonstrated that Arg 901 in the C-terminal tail of human AE1 (band 3, anion exchanger 1) had a functional role in conformational change during anion exchange. To further examine how Arg 901 is involved in conformational change, we expressed various Arg 901 mutants and alanine mutants of the C-terminal tail (from Leu 886 to Val 911) on the plasma membrane of Saccharomyces cerevisiae and evaluated the kinetic parameters of sulfate ion transport. As a result, Vmax decreased as the hydrophobicities of the 901st and peripheral hydrophilic residues increased, indicating that the hydrophobicity of the C-terminal residue is involved in the conformational change. We also found the alkali and protease resistance of the C-terminal region after Arg 901 modification with hydroxyphenylglyoxal (HPG) or phenylglyoxal (PG), a hydrophobic reagent. These results suggested that the increased hydrophobicity of the C-terminal region around Arg 901 leads to inefficient conformational change by the newly produced hydrophobic interaction. [Copyright &y& Elsevier]

Abstract: The aim of this research was to investigate the effect of caffeine on band 3 (the anion exchanger protein), haemoglobin function, caspase 3 activation and glucose-6-phosphate metabolism during the oxygenation–deoxygenation cycle in human red blood cells. A particular attention has been given to the antioxidant activity by using in vitro antioxidant models. Caffeine crosses the erythrocyte membrane and interacts with the two extreme conformational states of haemoglobin (the T and the R-state within the framework of the simple two states allosteric model) with different binding affinities. By promoting the high affinity state (R-state), the caffeine–haemoglobin interaction does enhance the pentose phosphate pathway. This is of benefit for red blood cells since it leads to an increase of NADPH availability. Moreover, caffeine effect on band 3, mediated by haemoglobin, results in an extreme increase of the anion exchange, particularly in oxygenated erythrocytes. This enhances the transport of the endogenously produced CO2 thereby avoiding the production of dangerous secondary radicals (carbonate and nitrogen dioxide) which are harmful to the cellular membrane. Furthermore caffeine destabilizes the haeme–protein interactions within the haemoglobin molecule and triggers the production of superoxide and met-haemoglobin. However this damaging effect is almost balanced by the surprising scavenger action of the alkaloid with respect to the hydroxyl radical. These experimental findings are supported by in silico docking and molecular dynamics studies and by what we may call the “caspase silence”; in fact, there is no evidence of any caspase 3 activity enhancement; this is likely due to the promotion of positive metabolic conditions which result in an increase of the cellular reducing power. [Copyright &y& Elsevier]

Background and Aims: Band 3 is a transmembrane protein of erythrocytes and its cytosolic part regulates glucose metabolism to proceed along the pentose phosphate pathway (PPP) or glycolytic pathway by binding with the central cavity of the β chain of deoxygenated hemoglobin and with some glycolytic enzymes competitively. In β thalassemia major and hemoglobin (Hb)Eβ thalassemia, β chain is either absent or distorted and glucose metabolism may be disturbed. We estimated adenosine triphosphate (ATP), glucose 6-phosphate dehydrogenase (G6PD) and aldolase activity in oxygenated and deoxygenated state of erythrocytes of β major, HbEβ thalassemia and normal controls to understand the hypothesis that major glucose metabolism within the erythrocytes of these diseases may proceed through the PPP. Methods: Fifty of each group of patients and 52 normal controls were included. Patients'' blood was collected 1 month prior to blood transfusion. G6PD and aldolase were estimated using a commercial kit. ATP was measured by spectrophotometric method. Results: Significantly low levels of erythrocytic ATP and higher levels of G6PD were found in two groups of patients. Aldolase level in deoxygenated hemolysate was significantly higher than oxygenated hemolysate in normal controls but no significant change was noticed in both types of thalassemic patients. Conclusions: In β thalassemia major and HbEβ thalassemia due to distortion of β chain, binding of deoxygenated hemoglobin with band 3 is inhibited and thus traffic control of glycolytic pathway is disturbed and shifted towards PPP. [Copyright &y& Elsevier]

Autosomal recessive distal renal tubular acidosis associated with Southeast Asian ovalocytosis. Background. A defect in the anion exchanger 1 (AE1) of the basolateral membrane of type A intercalated cells in the renal collecting duct may result in a failure to maintain a cell-to-lumen H+ gradient, leading to distal renal tubular acidosis (dRTA). Thus, dRTA may occur in Southeast Asian ovalocytosis (SAO), a common AE1 gene abnormality observed in Southeast Asia and Melanesia. Our study investigated whether or not this renal acidification defect exists in individuals with SAO. Methods. Short and three-day NH4 Cl loading tests were performed in 20 individuals with SAO and in two subjects, including their families, with both SAO and dRTA. Mutations of AE1 gene in individuals with SAO and members of the two families were also studied. Results. Renal acidification in the 20 individuals with SAO and in the parents of the two families was normal. However, the two clinically affected individuals with SAO and dRTA had compound heterozygosity of 27 bp deletion in exon 11 and missense mutation G701D resulting from a CGG→CAG substitution in exon 17 of the AE1 gene. Red cells of the two subjects with dRTA and SAO and the family members with SAO showed an approximate 40% reduction in sulfate influx with normal 4,4′-di-isothiocyanato-stilbene-2,2′-disulfonic acid sensitivity and pH dependence. Conclusion. These findings suggest that compound heterozygosity of abnormal AE1 genes causes autosomal recessive dRTA in SAO. [ABSTRACT FROM AUTHOR]

After a remark on linear response theory and non-equilibrium thermodynamics with internal variables foundation, this paper focuses on chicken blood characterization. Using a model for low frequencies, a new expression of the conductivity, is introduced. This new definition allows to the separation of the dielectric part from the conductivity part in complex dielectric functions. These thermodynamic elaborations supported by biochemical kinetic studies allowed to highlight some chicken RBC peculiarities. In this context, displacement conductivity value is well associated with the anion flux through band 3 protein exchanger and the value of complex entropy related to the complex conductivity, reflects the peculiar structure of nucleated chicken RBC. The study aims to open new perspectives of thermodynamic investigations that, if well supported by biochemical observations, can provide new research ideas for metabolic and eventually therapeutic investigations. • Complex conductivity in chicken blood. • Complex entropy in conductivity phenomena in chicken erythrocytes. • Anion exchanger functionality in chicken erythrocytes. • Dissipative phenomena by non-equilibrium thermodynamics with internal variables. [ABSTRACT FROM AUTHOR]

The main goal of our research was to study the modified proteins and activity of integral band 3 protein in erythrocytes of patients with end-stage renal failure during hemodialysis. Depending on the starting nosological variant 2 groups were formed. The first group included 27 patients with end-stage renal failurein the outcome of chronic pyelonephritis, the second – 20 patients with end-stage renal failure, developed on a background of chronic glomerulonephritis. The control group consisted of 15 healthy subjects. The patients of 1-th and 2-nd groups were treated with hemodialysis. The concentration of reactive protein carbonyl derivates, membrane-binding hemoglobin were detected in erythrocytes. Activity of band 3 protein was detected following the protocol of I. Mindukshev et al. (2010). Comparison the results obtained was performed using non-parametric Mann-Whitney U-test (for independent variables). Before hemodialysis the significant increasing of concentration of reactive protein carbonyl derivates and membrane-binding hemoglobin in erythrocytes of both group patients in comparison with healthy ones was observed. During hemodialysis the further augmentation of modified proteins in erythrocytes took place. Different changes in the activity of the protein band 3 in erythrocytes of patients during hemodialysis were found. The similar type of protein band 3 activity changing was determined in erythrocytes of 1-th group patients. There was positive pair correlation between concentration of the reactive protein carbonyl derivates and protein band 3 activity (r= 0,31, p<0,05). Two different types of protein band 3 activity changing were determined in erythrocytes of 2-th group patients. Thus, the differences in modified proteins concentration and protein band 3 activity that occurred in the erythrocytes of patients during hemodialysis were established. [ABSTRACT FROM AUTHOR]

Reverse transcriptase-polymerase chain reaction study of anion exchanger-2 in canine tissues and different Madin-Darby canine kidney cell types. Reverse transcriptase-polymerase chain reaction (RT-PCR) of mRNA from canine large intestine, skeletal muscle, pancreas, kidney, and spleen and from cultured wild-type and C7 and C11 Madin-Darby canine kidney (MDCK) cells revealed considerable variation in anion exchanger (AE)1 and AE2 mRNA levels between the tissues. Similar high levels of AE2 mRNA were detected in all the MDCK cell populations. AE2 in MDCK cells is probably the basolateral Cl − / HCO 3 − exchanger common to the principal and β-intercalated cells. [ABSTRACT FROM AUTHOR]