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Low-level laser therapy (LLLT) is widely used in clinical practice for treatment of various pathologies. It is assumed that LLLT impact on microcirculation is among the mechanisms underlying its therapeutic effect. The microcirculation disorder is observed in the pathogenesis of any inflammatory process and is significantly influenced by red blood cells (RBCs). On this point, studying the RBCs morphology under the influence of LLLT on alterated organism is of scientific interest and practical importance. The aim of the present study was to analyze the LLLT effect on morphokinetic parameters of RBCs in hyperadrenalinemia. The LLLT effect was analyzed on rats intraperitoneally injected with adrenaline hydrochloride solution (0.1 mg/kg). As the comparison groups, the effects of LLLT, adrenaline, or saline injection as well as the parameters of intact animals were studied. LLLT was applied on the occipital region of rats for 10 min. The light irradiation with pulse frequency 415 Hz at 890 nm wavelength and average power density in the plane of the output window at 193 μW/cm2 was used. The dynamics of morphological characteristics of RBCs was studied by phase interference microscopy; the RBC electrophoretic mobility was tested by microelectrophoresis technique; photometric analyses of the RBCs amount, hemoglobin content, and osmotic fragility were performed. The adrenaline injection resulted in a significant increase in the amount of RBC pathological forms and a decrease in discocytes and normocytes by more than 50%. An increase in the optical density of RBC phase portraits, a decline in osmotic resistance, and electronegativity of RBC membranes and a reduction of their number in peripheral blood were also registered. The revealed effects persisted for 1 week after the adrenaline administration. LLLT did not significantly impact on the RBC parameters 1 h after adrenaline injection. However, a day later, LLLT reduced the severity of the adrenaline effect on RBSs, which was manifested in a decreased amount of the pathological forms of RBCs, restored RBC phase portraits, higher electrophoretic mobility and osmotic resistance, and RBSs amount in peripheral blood restored up to the level of intact animals. We suppose that the mechanism of LLLT action is realized both at cellular level through the laser radiation effect on RBC membranes, and at systemic level through the activation of stress-realizing systems of the organism with subsequent limitation of inflammatory response.

Nanoparticles with desirable properties and functions have been actively developed for various bio-medical research, such as in vivo and in vitro sensors, imaging agents and delivery vehicles of therapeutics. However, an effective method to deliver nanoparticles into the intracellular environment is a major challenge and critical to many biological studies. Current techniques, such as intracellular uptake, electroporation and microinjection, each have their own set of benefits and associated limitations (e.g., aggregation and endosomal degradation of nanoparticles, high cell mortality and low throughput). Here, the well-established microelectrophoresis technique is applied for the first time to deliver nanoparticles into target cells, which overcomes some of these delivery difficulties. Semiconductive quantum dots, with average hydrodynamic diameter of 24.4 nm, have been successfully ejected via small electrical currents (−0.2 nA) through fine-tipped glass micropipettes as an example, into living human embryonic kidney cells (roughly 20 - 30μm in length). As proposed by previous studies, micropipettes were fabricated to have an average tip inner diameter of 206 nm for ejection but less than 500 nm to minimize the cell membrane damage and cell distortion. In addition, delivered quantum dots were found to stay monodispersed within the cells for approximately one hour. We believe that microelectrophoresis technique may serve as a simple and general strategy for delivering a variety of nanoparticles intracellularly in various biological systems.

Срыв адаптационных возможностей организма может стать патогенетической основой различных заболеваний. Длительный выброс адреналина в кровь вызывает кататоксические эффекты, что делает актуальным поиск эффективных средств и методов коррекции гиперадреналинемии. Цель работы - изучение влияния низкоинтенсивного лазерного излучения (НИЛИ) на электрофоретическую подвижность эритроцитов, процессы липопероксидации и структуру надпочечников при адреналовой токсемии у крыс. Методика. Адреналовую токсемию моделировали внутрибрюшинным введением адреналина-гидрохлорида (0,1 мг/кг). Животным 1-й группы вводили только адреналин, животных 2-й - через 30 мин после введения адреналина облучали НИЛИ, крысы 3-й группы получали только воздействие НИЛИ, контролем служили интактные животные (4-я группа). Воздействие НИЛИ проводилось на затылочную область в течение 10 мин. В качестве источника излучения применяли аппарат лазерный терапевтический Успех (ГП Восход ), основанный на низкоинтенсивном импульсном излучении (длина волны - 0,890,05 мкм, частота импульсов 415 Гц, плотность средней мощности излучения - 193 мкВт/см2, площадь облучаемой поверхности 20 см2). Забор крови производили через 1 ч, 24 ч и 1 нед после начала эксперимента. Определяли уровень малонового диальдегида по реакции с тиабарбитуровой кислотой электрофоретическую подвижность эритроцитов изучали методом микроэлектрофореза. Структуру надпочечников изучали морфологическими методами. Результаты. Показано, что НИЛИ на фоне адреналина (2-я группа) через 1 нед нивелировало снижение электрофоретической подвижности эритроцитов, восстанавливало уровень малонового диальдегида до значений интактной группы. Морфологическая картина надпочечников в этой группе не отличалась от таковой у интактных животных, тогда как при действии адреналина (1-я группа) не происходило восстановления исследуемых показателей до физиологической нормы. Заключение. Полученные в ходе эксперимента данные свидетельствуют о корригирующем действии низкоинтенсивного лазерного излучения при адреналовой токсемии у животных. Механизм действия низкоинтенсивного лазерного излучения, вероятно, носит системный характер и связан с воздействием на стресс-реализующие системы организма., Maladaptation results in the third stage of stress, exhaustion, and, thus, may underlie many diseases. Prolonged release of epinephrine into blood exerts catatoxic effects therefore, searching for effective methods for correction of hyperadrenalinemia is relevant. Presently, low-intensity laser therapy (LILT) is commonly used in medicine. However, the introduction of LILT to clinical practice is largely empirical. The aim of this study was to analyze the effect of LILT on electrokinetic potential of red blood cells (RBC), lipid peroxidation (LPO), and the morphology of adrenal glands in adrenal toxemia in rats. Methods. Adrenal toxemia was modeled by intraperitoneal administration of epinephrine hydrochloride (0.1 mg/kg) to rats. Animals of group 1 received epinephrine alone animals of group 2 received LILT 30 min prior to epinephrine administration rats of group 3 received LILT alone and intact rats of group 4 were used as control. Blood was withdrawn at one hour, 24 h, and one week of the experiment onset. The RBC zeta potential, which characterizes the morpho-functional state of membranes, was determined by measuring the effect of low-intensity laser therapy on RBC electrophoretic mobility using microelectrophoresis. LPO as an indicator of cell membrane injury was determined by concentration of malonic dialdehyde (MDA). The structure of adrenal glands was studied histologically. Results. LILT combined with epinephrine (group 2) alleviated the decrease in RBC electrophoretic mobility and restored the MDA level to values of the intact group at one week. Morphological structure of adrenal glands in group 2 did not differ from that in control whereas epinephrine (group 1) did not restore the study parameters to physiologically normal values. Conclusion. The study showed that LILT exerted a correcting effect in experimental adrenal toxemia. The mechanism of this effect is likely systemic and related with the effect on stress systems of the body., №4 (2019)

The sperm membrane undergoes extensive surface remodeling as it matures in the epididymis. During this process, the sperm is encapsulated in an extensive glycocalyx layer, which provides the membrane with its characteristic negative electrostatic charge. In this study, we develop a method of microelectrophoresis and standardize the protocol to isolate sperm with high negative membrane charge. Under an electric field, the percentage of positively charged sperm (PCS), negatively charged sperm (NCS), and neutrally charged sperm was determined for each ejaculate prior to and following density gradient centrifugation (DGC), and evaluated for sperm DNA damage, and histone retention. Subsequently, PCS, NCS, and neutrally charged sperm were selected using an ICSI needle and directly analyzed for DNA damage. When raw semen was analyzed using microelectrophoresis, 94 % were NCS. In contrast, DGC completely or partially stripped the negative membrane charge from sperm resulting PCS and neutrally charged sperm, while the charged sperm populations are increased with an increase in electrophoretic current. Following DGC, high sperm DNA damage and abnormal histone retention were inversely correlated with percentage NCS and directly correlated with percentage PCS. NCS exhibited significantly lower DNA damage when compared with control (P

This Review describes how in the period 1940-1959 cell electrophoresis (in the earlier literature often referred to as 'microelectrophoresis') was used to explore the surface chemistry of cells. Using the erythrocyte as a suitable model for the study of biological membranes, the early investigators were agreed on the presence of negatively charged groups at the surface of this cell. The contemporary dogma was that these were phosphate groups associated with phospholipids. Work in the 1960s, particularly on changes in the electrokinetic properties of erythrocytes following treatment with proteolytic enzymes, lead to the realization that the negatively charged groups at the red cell surface are predominantly due to sialic acids carried on glycoproteins. It quickly became apparent from cell electrophoresis that sialic acids have a ubiquitous presence on the surface of animal cells. This finding required that any complete model of the plasma membrane must include glycosylated molecules at the cell periphery, thus laying the foundations for the field termed 'Glycobiology of the Cell Surface'.

C60 fullerenes are spherical molecules composed purely of carbon atoms. They inspire a particularly strong scientific interest because of their specific physico-chemical properties and potential medical and nanotechnological applications. In this work we are focusing on studying the influence of the pristine C60 fullerene on biological activity of some aromatic drug molecules in human buccal epithelial cells. Assessment of the heterochromatin structure in the cell nucleus as well as the barrier function of the cell membrane was performed. The methods of cell microelectrophoresis and atomic force microscopy were also applied. A concentration-dependent restoration of the functional activity of the cellular nucleus after exposure to DNA-binding drugs (doxorubicin, proflavine and ethidium bromide) has been observed in human buccal epithelial cells upon addition of C60 fullerene at a concentration of ~10(-5 )M. The results were shown to follow the framework of interceptor/protector action theory, assuming that non-covalent complexation between C60 fullerene and the drugs (i.e., hetero-association) is the major process responsible for the observed biological effects. An independent confirmation of this hypothesis was obtained via investigation of the cellular response of buccal epithelium to the coadministration of the aromatic drugs and caffeine, and it is based on the well-established role of hetero-association in drug-caffeine systems. The results indicate that C60 fullerene may reverse the effects caused by the aromatic drugs, thereby pointing out the potential possibility of the use of aromatic drugs in combination with C60 fullerene for regulation of their medico-biological action.

The electric properties of bacteria determine their non-specific interactions with the environment, in particular their pathogenic activity. The electric polarizability of Escherichia coli HB101 (K-12 strain) was studied while inactivation with ethanol (20–40 vol.%). The current investigation might be regarded as a continuation of previous research on the polarizability of E. coli at lower ethanol concentration (≤ 20 vol.%) and higher frequencies (≥ 20 kHz). The bacteria polarizability at low frequencies (4 Hz) shows anomalies (unexpected increase in the polarizability at certain ethanol concentrations), while the parameter decreases with an increase in the ethanol concentration at higher frequencies. We investigated for the possible reasons causing the anomalies — in our case reduced to the medium dielectric permittivity, the average cell length and the surface electric charge density distribution, related to bacterial lipopolysaccharides. We suggest a hypothesis for the molecular mechanism of changing the surface charge of E. coli, carried by lipopolysaccharides, induced by the non-ionic ethanol.

The viability of the probiotic strain Lactobacillus plantarum subsp. plantarum, after its passage through simulated gastric and pancreatic juices, was evaluated as function of its pre-growth in a medium containing the known prebiotics pectin or inulin, and was compared to glucose used as control. The presence of pectin or inulin did not markedly affect the growth (10.07 log10 colony forming units/mL and 10.28 log10 colony forming units/mL for pectin and inulin respectively versus 10.42 log10 colony forming units/mL obtained for glucose). Pectin and inulin, in contrast to glucose, induced cell stress resistance against gastrointestinal juices (D log101.5 and 2.4 colony forming units/mL respectively, versus D log10 4.0 for glucose). The data were corroborated by the analysis of the protein pattern following stress treatments which, in the case of microbial cells grown with glucose, revealed a more marked protein degradation after the double passage through simulated gastric and intestinal juices. Inulin stimulated the production of the relevant healthy bio-molecule butyrate, which amount was 30% higher respect of growth in the presence of glucose. Inulin and pectin improved cell DPPH scavenging activity, and an impressive hydrophobicity (35.28% and 34.81%, respectively) was observed with respect to the microbial growth in presence of glucose (3.39%).

Considering the influence on the downstream process of microalgae recovery by cell surface characteristics, in this paper , Microelectrophoresis and Hydrocarbon adsorption have been used for researching the surface electrical property and hydrophobicity of microalgae. The influence on surface characteristics of microalgae cell have been studied by the solution chemistry condition of pH and cationic flocculant. The results show that: The surface charge of microalgae cell is negative under the natural condition. The surface electrical property decreases with the declining pH when pH is less than 7 , but the isoelectric point is not observed until pH low to 1, while it changes little with the pH increased when pH is more than 7; Within the value of experimental pH, microalgae cells have strong hydrophobicity, which increases with the decreasing pH when pH is less than 7 and rises with the pH increased when pH is more than 9. It attains to the minimum value when the pH is about 8. The hydrophobicity of microalgae increases with anhydrous ferric chloride(FeCl3) when cationic flocculant (FeCl3) is added , but the trend became weaker. So the hydrophobicity can be improved by cationic flocculant, which can promote the microalgae cohesion.

The amixine-induced early changes in the electrophoretic mobility (EPM) of murine splenic T lymphocytes were studied in vitro by the microelectrophoresis technique. It has been found that T lymphocytes treated with amixine have a greater EPM within the first hours of amixine addition than control cells. This change in EPM depends on the concentration of amixine in the medium and the duration ofamixine exposure. It was concluded that the amixine-treated cells have a greater net negative surface charge density than control cells. This effect may play an important role in the cell-cell interaction during the immune response.

The feasibilities of the Kelvin probe mode were shown to estimate a surface potential of lymphocytes from the patients with leukemia. Having compared the values of the surface potential obtained by the traditional method of microelectrophoresis and by the Kelvin probe mode, it was established that the use of the atomic force microscope made it possible to obtain data which were of specified diagnostic importance while studying lymphocyte functional status at different stages in leucopoiesis and indicated progression of the pathological process.

The effects of dissolved oxygen tension during bacterial growth and acclimation on the cell surface properties and biochemical composition of the bacterial pathogens Escherichia coli O157:H7 and Yersinia enterocolitica are characterized. Three experimental techniques are used in an effort to understand the influence of bacterial growth and acclimation conditions on cell surface charge and the composition of the bacterial cell: (i) electrophoretic mobility measurements; (ii) potentiometric titration; and (iii) ATR-FTIR spectroscopy. Potentiometric titration data analyzed using chemical speciation software are related to measured electrophoretic mobilities at the pH of interest. Titration of bacterial cells is used to identify the major proton-active functional groups and the overall concentration of these cell surface ligands at the cell membrane. Analysis of titration data shows notable differences between strains and conditions, confirming the appropriateness of this tool for an overall charge characterization. ATR-FTIR spectroscopy of whole cells is used to further characterize the bacterial biochemical composition and macromolecular structures that might be involved in the development of the net surficial charge of the organisms examined. The evaluation of the integrated intensities of HPO(2)(-) and carbohydrate absorption bands in the IR spectra reveals clear differences between growth protocols. Taken together, the three techniques seem to indicate that the dissolved oxygen tension during cell growth or acclimation can noticeably influence the expression of cell surface molecules and the measurable cell surface charge, though in a strain-dependent fashion.

The peculiarities of frog erythrocyte electrophoretic mobility, coupled to the seasonal course of temperatures, have been studied. At the periods of anabiosis and of burst of hemopoiesis, in the vascular bed there increases the portion of functionally young erythrocytes (up to 22%) with increased values of the cell membrane surface charge. Preparation to winter is accompanied by a rise of the number of circulating functionally worn-down blood cells (up to 60%) with low values of the superficial charge and low mobility in electrical field. Use of the cell microelectrophoresis method of evaluation of seasonal activity of frog erythrocytes allows obtaining objective data about the cellular surface charge and its depending functional cell activity without submitting the erythrocytes to modifying actions.

The method of microelectrophoresis is employed to study the dependence of the ζ-potential of microcrystalline cellulose particles on the concentration (10−6–10−3 M) and pH (2–11) of aqueous aluminum chloride, nitrate, and sulfate solutions. It is shown that, in the absence of aluminum salts, the isoelectric point (IEP) of the particles is independent on the nature of acid anions and is observed at pH 3.2. The addition of aluminum salts in concentrations as low as 2 × 10 −6 M for chloride and nitrate and 1 × 10−5 M for sulfate causes a shift of IEP to a less acidic region (pH 3.8), the value of which is virtually independent of the nature of the salt. As the concentration of salts is increased, the ζ-potential becomes positive, rises with an increase in pH to a maximum magnitude at pH 5.0–6.0, and decreases further until the second IEP (pH ∼ 6.5–7.0) is reached. At higher pH values, the ζ-potential becomes negative again. The observed ζ(pH) dependences are explained by the formation of hydrolyzed aluminum species exhibiting different adsorbabilities on microcrystalline cellulose particles. It is shown that positively charged hydroxocomplexes formed in aluminum sulfate solutions are characterized by a lower adsorbability than hydroxocomplexes formed in chloride and nitrate solutions.

The pH dependences of electrokinetic potentials (EKP) of the cells of two Escherichia coli K-12 strains (D21 and JM 103) with known lipopolysaccharide (LPS) core composition have been determined by the method of microelectrophoresis. At pH 4.6–5.2, the negative surface charge of the cells with Re core LPS was reliably higher. It was shown that the interaction of bacteria with lysozyme results in a decrease of optical density of suspensions due to higher sensitivity of the cells with complete LPS core to hypotonic shock. LPS release from bacterial cell wall depended also on bacterial LPS core composition and increased with LPS core extension. Electrokinetic measurements and the study of the interaction of cells with lysozyme suggest that higher negative surface charge of E. coli JM 103 cells (Re type LPS) is associated with higher quantity and density of LPS packing in the cell wall as compared with the cells of E. coli D21 (Ra type LPS).

Nanocapsules containing hinokitiol (HKL) were prepared by an emulsion-diffusion method. In an emulsification step in preparing nanocapsules, cetyltrimethylamonium chloride (CTAC) was employed as a cationic emulsifier, Poly(epsilon-caprolactone) (PCL) was use as a wall material and HKL dissolved in octylsalicylate (OS) was used as a core material. The submicron-sized nanoparticle was observed on a TEM. The size ranged 55-234 nm and the mean diameters were 223 nm, which were determined by a dynamic light scattering method. According to the results of pH-dependent microelectrophoresis, the absolute value of the surface potential of the nanocapsules was greater than 20 mV. The nanocapsules were colloidally stable over the pH range of 3-11. The nanocapsules were included in two kinds of preparations, namely shampoo and hair tonic, and the preparations were applied every day for 3 weeks on the clipped backs of 6 week-old mouse (C57BL/6) to investigate the hair growth-promoting effect. The degree of hair growth was evaluated by image-analysing the photographs of the backs and, in parallel, by the histological observation of the formation and the growth of hair or hair bulbs. The results were compared with those of commercially available Minoxidil solution (3%). Phosphate buffered saline was used as a control. The in vivo hair growth-promoting effects of the two preparations were comparable to those of Minoxidil solution. These results are in a good agreement with the histological and structural changes of follicles of the model animals, of which skins were treated with either the testing samples or the control in the same way the experiments of in vivo hair growth promotion were performed.

Background. Efficient islet isolation represents a necessary requirement for successful islet transplantation as a treatment for type 1 diabetes. The choice of collagenase for pancreas digestion is critical for the isolation outcome, and Liberase™ is the most widely used enzyme, although large intra-batched variability in activity and efficiency has been observed. Methods.TheaimofthisstudywastocharacterizeLiberase™componentsandtheirrelativeroleinpancreasdigestion. Liberase batches were characterized by microelectrophoresis. Results. By means of microelectrophoresis, we identified three main proteins each with different prevalences between batches. Two proteins were found to correspond to class I (CI) and one to class II (CII) collagenase. In a series of 163 islet isolations, we observed that the CII correlated with islet yield (P0.001) and digestion time (P0.001); additionally,CIdirectlycorrelatedwithpurity(P0.028).Finally,whenCIIandoneoftheCIisoformswere50percentile,15 of 36 preparations were transplanted, with 27 of 127 transplanted in the other cases (P0.013). Conclusion. These results represent an important step toward the characterization of enzymes, with the final aim of identifying key components for a standardized product.

The objectives of this study were to prepare films from submicron chitosan/Eudragit® L100-55 polyelectrolyte complexes (CH/EL PEC) and to assess the influence of CH molecular weight and CH/EL mass ratio on their structure and drug-release properties. The films were obtained by a simple, environmentally friendly, casting/solvent evaporation method and the verapamil hydrochloride (VH) was used as model drug. Submicron size, narrow size distribution, and acceptable stability of CH/EL PECs were confirmed by DLS and laser Doppler microelectrophoresis. SEM analysis revealed nonporous inner structure and flat surface of the films. Interactions between comprising polymers and formation of CH/EL PEC were established by DSC and FT-IR spectroscopy. In vitro swelling and drug release studies revealed the pH sensitivity of the films, with burst drug release in acidic conditions (pH 1.2) and sustained release in phosphate buffers pH 5.8, 6.8, and 7.4. The slowest VH release was achieved from the films prepared from equal amounts of EL and CH of higher molecular weight, confirming the significance of the CH/EL ratio and CH molecular weight on their ability to sustain drug release. The obtained results suggested that presented, simple, and eco-friendly preparation procedure can be used to obtain pH-sensitive CH/EL PEC films with a promising potential as drug carriers. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42583.

The microelectrophoresis on gradient gels allows differentiation between the different types of proteinuria in 1 h in a one-step procedure. Due to their different molecular weights and forms, fibrinogen split products are separated by this method. The determination of fibrinogen split products not only offers a possibility for dicrimination between the various forms of glomerulonephritis but also offers a possibility for following the course of the disease.

Prior research has indicated that the two sperm cells of Nicotiana tabacum are dimorphic, suggesting that they may participate in preferential fertilization during in vivo fusion with the egg and central cells. To probe the mechanism of potential preferential fertilization in this plant, it will be necessary to use modern sensitive molecular techniques. For this purpose, two individual populations of two sperm cells, constituting the Svn (associated with the vegetative nucleus) and Sua (unassociated with the vegetative nucleus), were isolated in the thousands from tobacco pollen tubes with a micromanipulator as a preliminary step toward research on gametic recognition using molecular techniques. Microelectrophoresis of paired sperm cells from a single pollen tube was conducted at different developmental stages. Sperm cells isolated from 1-, 2-, 3- and 4-cm stylar lengths migrated to the negative pole, with the Sua displaying significantly greater electrophoretic mobility than the Svn, reflecting a more positively charged cell surface on the Sua. The sperm cells isolated from 1-cm style are very sensitive to electron potential in an electrophoretic field, presumably reflecting that they are still in a young state. Differences in cell surface charge between the Sua and Svn may be related with cell fate during fertilization.

Biogenic microcapsules comprised of l-α-dimyristoyl phosphatitic acid (DMPA)/human serum albumin (HSA) were prepared by stepwise adsorption of DMPA/HSA multilayers onto charged colloids and subsequent dissolution of the colloidal cores. The properties of both lipid/protein modified particles and the hollow capsules were characterized by microelectrophoresis, scanning electron microscopy, transmission electron microscopy, confocal laser scanning microscopy, and scanning force microscopy, respectively. Single particle light scattering together with small-angle X-ray scattering measurements revealed that DMPA forms a bilayer structure on the HSA surface. A combination of HSA and DMPA on hollow capsules is proposed as a biomimetic membrane model.

The dependence of NiO and Fe2O3 ζ-potential was investigated in the barbituric acid solutions (10−4 mol/l) as a function of pH by microelectrophoresis method. Shifting of pHIEP (the isoelectric point or IER) towards the acid zone for NiO and Fe2O3 in the solutions of barbituric acid (BA) in comparison with HCl shows the presence of the specific adsorption of the anion forms of BA. The complexation process of Ni(II) and Fe(III) ions with BA in the solution and on the surface of their oxides was examined by methods of conductometry and spectrophotometry. It was determined that nickel (II) and ferric (III) ions form complexes with BA both in solution and on the surface of their oxides.

The surface physicochemical properties of Listeria monocytogenes LO28 under different conditions (temperature and growth phase) were determined by use of microelectrophoresis and microbial adhesion to solvents. The effect of these parameters on adhesion and biofilm formation by L. monocytogenes LO28 on hydrophilic (stainless steel) and hydrophobic (polytetrafluoroethylene [PTFE]) surfaces was assessed. The bacterial cells were always negatively charged and possessed hydrophilic surface properties, which were negatively correlated with growth temperature. The colonization of the two surfaces, monitored by scanning electron microscopy, epifluorescence microscopy, and cell enumeration, showed that the strain had a great capacity to colonize both surfaces whatever the incubation temperature. However, biofilm formation was faster on the hydrophilic substratum. After 5 days at 37 or 20°C, the biofilm structure was composed of aggregates with a three-dimensional shape, but significant detachment took place on PTFE at 37°C. At 8°C, only a bacterial monolayer was visible on stainless steel, while no growth was observed on PTFE. The growth phase of bacteria used to inoculate surfaces had a significant effect only in some cases during the first steps of biofilm formation. The surface physicochemical properties of the strain are correlated with adhesion and surface colonization.

The effect of fatal carbon monoxide poisoning on equilibria between cell membranes and surrounding ions was described using a theoretical four-equilibria model. The model was developed to obtain parameters characterizing the interactions between solution ions and erythrocyte or thrombocyte membrane surface. The parameters are the total surface concentrations of both acidic and basic groups C A, C B and their association constants with solution ions K AH, K BOH. These parameters were used to calculate the theoretical values of surface charge density. The model was validated by comparison of these values to experimental data, which were determined from the electrophoretic mobility measurements of the blood cells. The experimental and theoretical surface charge density values agree at pH 2-8, and at higher pH, the deviation was observed.

Microcapsules were prepared by complex coacervation between gelatin (Type A) and carboxymethylcellulose (CMC). Triclosan (TS) dissolved in octyl salicylate (OS) was used a core material and glutaraldehyde as a crosslinking agent. The microcapsules on the scanning electron micrographs were spherical and exhibited core and shell morphology. The thermograms of freeze-dried microcapsules showed no evidence for the melting of TS, suggesting that TS remained dissolved in the cores of the microcapsules and did not exist as a crystalline solid even after the microcapsules were dried. Microelectrophoresis revealed that the point of zero charge of the microcapsules occured around pH 3.3, far below the isoelectric point of gelatin. This means that along with gelatin, CMC, a negatively charged polymer, constitutes the wall of microcapsules, decreasing the positive charges on the gelatin. The degree of release of TS and OS from the microcapsules in ethanol/water solvents was strongly dependent on the content of the al...

The influence of an alternating (50 Hz) electric field (5--110 V/cm) on the state of human buccal epithelium cells was studied by the methods of intracellular microelectrophoresis, heterochromatin staining with orcein, and indigo carmine staining for viability and membrane integrity evaluations. Electric field exposure induced an increase in electrophoretic mobility of cell nuclei, decreased numbers of heterochromatin granules near the inner membrane of cell nucleus, and induced cell membrane damage; but cell viability was conserved. Nuclear and cell membrane properties varied with electric field strength and age of the donors. The data obtained are interpreted as evidence of electric field induced activation of the functional state of nuclei.

The effect of acupuncture and microwave resonance therapy (MRT) on the electrophoretic motility of the cell nuclei of buccal epithelium was studied using the electronegative nuclei index in percent (ENN index, %) during treatment of patients with a duodenal ulcer and spinal osteochondrosis. This method was developed in Kharkov State University under the direction of Prof. V.G. Shakhbazov. A special device and a chamber were used to provide the intracellular microelectrophoresis of native cell nuclei. The tested methods of reflexotherapy had the normalizing effect on the ENN index, %. Acupuncture and MRT similarly affect the human organism in terms of the tested index. These findings confirmed a direct relationship between the human health status and ENN index, % which was determined by us earlier. This method makes it possible to provide the additional monitoring of the patient’s health status.

An investigation of the mechanism of adsorption of guar, a natural nonionic polysaccharide, at the talc–aqueous solution interface has been performed. Hydrophobic interactions were found to dominate the adsorption process, leading to adsorption of the guar onto hydrophobic sites, i.e. the talc “face”. Hydrogen bonding made only a small contribution to the adsorption, whilst chemical interactions were completely absent. In the case of ionically modified guars, the electrostatic contribution to the overall thermodynamics of adsorption was weak. Both unmodified and modified guars were found to adsorb in a very flat conformation with in excess of 75% of the constituent segments present in the form of “trains” at the talc–aqueous solution interface. Determinations of adsorbed layer thickness, calculated from microelectrophoresis measurements, supported this finding. The mannose backbone of the guar chain adsorbed to the talc surface, leaving the pendant galactose groups protruding into the bulk solution.

The aims of this study are to optimize conditions for the preparation, stabilization, and harvesting of heparin/gelatin microcapsules prepared by complex coacervation. Microelectrophoresis and dry coacervate weight were used to determine the optimum conditions of pH and ionic strength for maximum heparin/gelatin coacervate yield. Heparin/gelatin microcapsules were formed by complex coacervation in the presence and absence of poly(1-vinyl-2-pyrrolidone) (PVP), which was used as a stabilizer. The microcapsules were collected using a spray-drying technique. Microcapsule particle size was analyzed using an AccuSizer optical sizer. Optimized conditions for maximum coacervate yield were pH 2.6, ionic strength 10 mM, and a 1:2 heparin/gelatin A ratio. PVP stabilized the heparin/gelatin coacervate droplets and reduced droplet aggregation during spray-drying. The mean particle diameter of the spray-dried coacervate droplets was lower in the presence of PVP and was unaffected by PVP concentration (in the range 0.5-2.0% w/w). Heparin/gelatin microcapsules, prepared under conditions optimized for maximum coacervate yield, were stabilized without the use of chemical cross-linking agents. Stabilization was achieved by a combination of the addition of PVP and spray-drying.

The interaction of small cationic vesicles composed of dioctadecyldimethylammonium bromide (DODAB) with normal versus transformed mouse fibroblasts is described using cell microelectrophoresis, turbidimetry, and cell viability assays over a wide range of DODAB concentrations (10-7−10-3 M). Normal and transformed cells (104 cells/mL) attain a point of zero charge at, respectively, 18.0 and 1.6 μM DODAB. Further increasing DODAB concentration (C) generates positively charged cells. At 105 cells/mL and C ≥ 50 μM, DODAB induces cell−cell adhesion. For transformed and normal cells, peak adhesion occurs at 100 and 1000 μM DODAB, respectively. Upon 0.5 h interaction time with 100 μM DODAB, at 104 cells/mL, 20% of cell death is obtained for normal cells whereas transformed cells remain unaffected. Transformed cells have a higher affinity for DODAB vesicles than their normal counterparts but are more resistant to DODAB-induced cell death. The results indicate that DODAB vesicles interact with cells with very high ...

When a number of experimental studies in bioelectromagnetics were reviewed, those in which weak, exogenous extremely low frequency (ELF) fields were applied in fixed juxtaposition to their target tissues, were found to initiate mitogenesis or mitogenesis-related signals more successfully than when the target tissue moved freely during the irradiation. It is suggested that ELF fields in fixed juxtaposition to their target tissue and implanted foreign bodies or endogenous tissues with a significant zeta potential, mimic bioelectric fields generated at wounds. When the potential is high enough, they assist healing by moving cells into the wound and stimulating quiescent cells at the wound margin to cycle. Electrophoresis may help the initial migration of cells into the wound to form a clot, and migration of fibroblasts and epithelial cells from the wound margin. When exposed for a long time in a fixed juxtaposition to a potential gradient too weak to show in situ microelectrophoresis along the cell membrane surface, surface particles may coalesce to form microclusters, where like-charged surface particles are in close proximity, and growth factor receptor oligomerization and other cycle-initiating reactions are facilitated.

The aim of this study is to determine the toxic and genotoxic damages produced by a helium plasma needle upon HeLa and E. coli (OG100 and PQ30) cell cultures. For HeLa cells survival (MTT) and microelectrophoresis comet) assays were performed; meanwhile in E. coli, viable count and genotoxicity by the chromotest were evaluated. The outcomes indicate that the plasma exposures on HeLa cells undergo more toxicity and genotoxicity as treatment time increases. With respect to E. coli, plasma exposure generated toxicity, but no genotoxicity could be detected with this system. In the strain OG100, defective in a protection mechanism to oxidizing agents, there was a reduction in the survival of one order of magnitude compared to the wild type strain PQ30. It suggests that such reduction is due to the plasma by means of the reactive oxygen and nitrogen species (RONS) generated during atmospheric air interaction.

Electrophoretic mobility measurements have been used to characterize monodispersed colloidal particles of silica, silica coated with alumina (cores), of these cores incorporating a dye (pigments), and finally of pigments coated with polymers. The latter consisted of poly(divinylbenzene), of poly(vinylbenzyl chloride), and of their copolymers, synthesized directly on the core or pigment particles, with and without subsequent sulfonation.

The effects of pretreatments on the zeta potential characteristics of hematite were investigated on a number of hematite samples. The bulk of the test work was conducted on a sample of naturally occurring hematite from the Iron Prince deposit in the Middleback Range area of South Australia. The iep of the ROM ore was measured as 2.6, which was only slightly raised by ultrasonic cleaning. When the ore was contacted with dilute acid over a prolonged period the iep was raised to 6.7, the value commonly quoted for natural hematites. Contact of the hematite ore with HCl solutions for only 1 hour did not increase the iep to this value. Removing the slimes from the ore gave an iep value of 3.5, which was only slightly raised with contact with HCl. The value of 3.5 may be close to the true value of the iep for this ore. Slimes removed from the ore plus assay residue where the iron has been removed gave iep values typical for silica. The iep for a high grade hematite sample from Iron Knob was 5.3 and this was not changed by contact with HCl. Washing the Iron Prince ore with NaOH and HCl followed by NaOH had little influence on the iep of the ore, and still reflected the presence of silica. The iep of freshly precipitated ferrihydrate was 7.5, typical of values obtained for synthetic hematites. The zeta potential characteristics of silica activated by ferric ions gave similar characteristics to that of the acid washed hematite ore. This suggests that the major species under test in the microelectrophoresis cell after prolonged acid washing of the hematite ore is in fact ferric-activated silica from the fine particles removed by centrifugation prior to testing since it is known that the silica is concentrated in the fine fractions of the hematite ore. This finding is further complicated by the fact that both ferrihydrate and AR ferric oxide have iep values in a similar range. These three species could co-exist under the conditions of the microelectrophoresis testin Refereed/Peer-reviewed

The effect of the zeta (ζ) potential of activated carbon on the adsorption of cationic dyes from aqueous solution has been studied. The pHzpc of the zero-point charge of activated carbon has been measured by microelectrophoresis. Plots of saturated amount adsorbed for methyl green and methyl violet on activated carbon versus zeta potential have also been determined. The results show that the electrostatic interaction between cationic dyes and the surface of activated carbon has a great effect on adsorption capacity. When the zeta potential of activated carbon is lower than -30 mV, the electrostatic attraction between cationic dyes and the carbon surface greatly increases the adsorption capacity. However, when the potential of activated carbon is between -30 and +60 mV the electrostatic force between dyes and the carbon surface is diminished and the adsorption capacity of activated carbon is approximately unchanged. The capacity is significantly reduced due to the electrostatic repulsion between cationic dyes and the carbon surface when the zeta potential is higher than +60 mV. The adsorption kinetic and thermodynamic parameters as functions of pH have been determined. The mechanism for adsorption of cationic dyes on activated carbon has also been studied.

The surface electric properties of thylakoids and Photosystem II-enriched particles subjected to proteolytic treatment were investigated by electric light scattering and microelectrophoresis. The observed variation of the charge asymmetry (permanent dipole moment) and electric polarizability upon treatment of thylakoids with trypsin in a wide concentration range and different time of enzyme action, associated with the removal of positively charged polypeptides from the thylakoid membranes, correlated with the increase of the electrokinetic charge. The higher transversal charge asymmetry of trypsin-treated Photosystem II fragments could be connected with destacking of the paired membranes upon treatment with trypsin and formation of unpaired single membrane fragments.

Granular activated carbon (GAC) from an operating water treatment plant was used to study the effectiveness of a chemical regeneration procedure. The ability of new, used and regenerated carbon to remove dissolved organic (DOC) and taste and odour causing compounds from water was established using simple column experiments. Surface properties of the carbon were studied using X-ray photoelectron spectroscopy, surface titrations and microelectrophoresis. The results have been interpreted in terms of surface characteristics caused by variation in pH.

We and other investigators have demonstrated the stimulation of luteinizing hormone secretion following the microinjection of neurotensin (NT) into the medial preoptic area in female rats. The present study electrophysiologically examined the action of the peptide in the same brain region. Microelectrophoresis of NT produced either excitation or inhibition in 24% of the medial preoptic neurons tested in oestrogen-primed and unprimed ovariectomized animals. Effective blockade of NT-induced excitatory and inhibitor unit responses by means of the simultaneous application of an antiserum to NT (anti-NT) indicated that they were produced by specific actions of the peptide. In addition, anti-NT by itself altered the spontaneous firing rate in some NT-responsive cells. These findings are in accord with the hypothesis that the preoptic area is a site of the action of NT in the female rat.

Escherichia coli surface characteristics including hydrophobicity, electrophoretic mobility and surface functional groups' composition were investigated. These characteristics were determined respectively by water contact angle measurements, microelectrophoresis and x-ray photoelectron spectroscopy (XPS). The relation between the physicochemical properties and functional groups' composition was also examined. The electrophoretic mobility at pH 7 appeared to be governed on the cell surface by the (O=C) functional groups. The cell surface's hydrophilicity was associated with high levels of (C-(O.N)) and (OH-(C-O-C)) functional groups, whereas the cell surface's hydrophobicity was associated with (C-(C,H)) functional groups. Características de superfície de Escherichia coli, tais como hidrofobicidade, mobilidade eletroforética e composição dos grupos funcionais de superfície, foram estudadas. Essas características foram determinadas por medidas de angulo de contato com água, microeletroforese e espectroscopia fotoeletrônica de raio-X (XPS), respectivamente. A relação entre as propriedades fisicoquímicas e a composição dos grupos funcionais foi também examinada. Aparentemente, a mobilidade eletroforética em pH 7 é controlada na superfície celular pelos grupos funcionais (O=C). A hidrofilicidade da superfície celular estava associada com altos níveis dos grupos funcionais [C-(O.N)] e [OH-(C-O-C)], enquanto a hidrofobicidade estava associada com os grupos funcionais [C-(C,H)].

From microelectrophoretic measurements on multilamellar liposomes as a function of lipid composition and pH of the medium, the pH dependence of the ζ-potential was found to be the same for liposomes in both the absence and presence of insulin. For liposomes without insulin, it is concluded that dicetyl phosphate (DCP) is incorporated at the external surface of bilayers consisting of phosphatidylcholine and cholesterol. Furthermore, the apparent pKa for the -PO4H group of DCP in liposomes was 4.5. On the other hand, insulin entrapped in liposomes did not affect the ζ-potential of liposomes. The amount of entrapped insulin solution was the same as that of entrapped calcein solution, the latter being known to be distributed in the internal aqueous compartment of liposomes. By means of incubating the mixed solution of empty liposomes and insulin, the equilibrium constant for adsorption (k) and the amount of insulin adsorbed to liposomes at saturation (X∞) could be determined from Langmuir plots. The present data suggest that the polar regions of the insulin molecule do not occur at the liposomal surface. This may be the result of the interaction between insulin and liposomes being hydrophobic in nature.

The present study was aimed to identify peculiarities of the polypeptide composition in three morphofunc-tionally different classes of neurons of the rat brainstem: giant multipolar neurons of n. reticularis gigantocellularis, relay sensory neurons of lateral geniculate body and pyramidal neurons of the pyramidal layer of the CA3 – CA4 fields of hippocampus. The method of free hand dissection of neurons and sodium dodecyl sulfate (SDS) slab gel microelectrophoresis in our modifications were used. Polypeptide peculiarities for each class of investigated neurons have been found. Most of these polypeptides belong to the low molecular weight range (8.8–24.3 KD) of the polypeptide spectra and only some of them to the high one (64.6–75.3 KD).

To determine the effects of total plasma cholesterol on the electrokinetic properties of erythrocyte membranes of healthy volunteers and patients with chronic cerebral ischemia (CCI).Authors studied the erythrocytes from venous blood of 95 patients with CCI and 54 healthy people (controls). To perform an electrophoretic cell analysis of erythrocytes, we used the shorthand method of computer microelectrophoresis.Plasma cholesterol level increased with the age. In the control group, there were the increase in percentage of fixed red blood cells, decrease in the amplitude of oscillations and electrophoretic mobility of red blood cells. In CCI patients, a significant increase in the share of fixed red blood cells, decrease in the amplitude of oscillations and electrophoretic mobility were observed compared to the controls. An increase in percentage of fixed red blood cells as well as in the qualitative heterogeneity of red blood cells in the amplitude of the oscillations was identified both in patients and controls, regardless of sex and age, with higher levels of total cholesterol.Цель исследования - изучить влияние на электрокинетические свойства мембран эритроцитов общего холестерина плазмы крови в условиях относительной нормы и при хронической ишемии головного мозга (ХИМ). Материал и методы. Исследовали эритроциты венозной крови 95 пациентов с хронической ишемией мозга и 54 практически здоровых (контроль). Для выполнения электрофоретического клеточного анализа эритроцитов использовался экспресс-метод компьютерного микроэлектрофореза. Результаты и заключение. С увеличением возраста был выявлен рост уровня холестерина плазмы крови. В контрольной группе с увеличением возраста увеличивалась доля неподвижных эритроцитов, уменьшались амплитуда колебаний и электрофоретическая подвижность эритроцитов (ЭФПЭ). У пациентов с ХИМ по сравнению с контролем отмечались достоверное увеличение доли неподвижных эритроцитов, снижение амплитуды колебания и ЭФПЭ. При увеличении уровня общего холестерина плазмы крови вне зависимости от возраста и пола обследованных как у здоровых, так и у пациентов с ХИМ отмечались рост доли неподвижных эритроцитов, а также возрастание качественной гетерогенности эритроцитов по амплитуде колебаний.

Photon correlation spectroscopy and microelectrophoresis are investigated as tools to characterize SERS-active systems. Mutual relations of SERS spectra, UV/vis spectra, hydrodynamic size and zeta-potential are studied for systems based on Ag sol and two different adsorbates (2,2′-bipyridine and pefloxacin).

Summary Background The skin represents an accessible somatic tissue for therapeutic gene transfer. The superficial lipophilic layer of the skin, the stratum corneum, however, constitutes a major obstacle to the cutaneous delivery of charged macromolecules such as DNA. Objectives To determine whether silicon-based microneedles, microfabricated via a novel isotropic etching/BOSCH reaction process, could generate microchannels in the skin of sufficient dimensions to facilitate access of lipid : polycation : pDNA (LPD) nonviral gene therapy vectors. Methods Scanning electron microscopy was used to visualize the microconduits created in heat-separated human epidermal sheets after application of the microneedles. Following confirmation of particle size and particle surface charge by photon correlation spectrocopy and microelectrophoresis, respectively, the diffusion of fluorescent polystyrene nanospheres and LPD complexes through heat-separated human epidermal sheets was determined in vitro using a Franz-type diffusion cell. In-vitro cell culture with quantification by flow cytometry was used to determine gene expression in human keratinocytes (HaCaT cells). Results The diffusion of 100 nm diameter fluorescent polystyrene nanospheres, used as a readily quantifiable predictive model for LPD complexes, through epidermal sheets was significantly enhanced following membrane treatment with microneedles. The delivery of LPD complexes either into or through the membrane microchannels was also demonstrated. In both cases considerable interaction between the particles and the epidermal sheet was observed. In-vitro cell culture was used to confirm that LPD complexes mediated efficient reporter gene expression in human keratinocytes in culture when formulated at the appropriate surface charge. Conclusions These studies demonstrate the utility of silicon microneedles in cutaneous gene delivery. Further studies are required to elucidate fully the influence of the physicochemical characteristics of gene therapy vectors, e.g. particle diameter and surface charge, on their diffusion through microchannels and to quantify gene expression in vivo.

This report considers the rehabilitation of people with locomotor apparatus dysfunction including those diseases complicated by inflammatory processes. The proposed system provides required mutual location of fracture separate fragments as well as their movement by three independent actuators with unique kinematics. The actuators generate specified movement velocity of either of three kinematics pairs within the range 0.05-5 mm/24 hours. We have proposed unique methods of bone tissue stimulation by microwaves with radiation intensity up to 10 mW/cm/sup 2/. Experimental models of the autodistracktoric system with microwave stimulation of regeneration in combination with simulation by a constant magnetic field and microelectrophoresis in biologically active points (e.g. using mumye solution) are patented in Ukraine. Some experimental laboratory elements of the autodistracktoric system have been manufactured and tested. The following tasks are to be fulfilled: development of both schematic and structure of the automatic autodistracktoric system, providing movement of separate fracture fragments to optimize the bones knitting; wide introduction of elements stimulating processes of tissues regeneration, where the regeneration is accelerated by 10 times owing to the complex influence on the fracture region and biologically active points of various physical factors, such as microwave radiation, constant magnetic fields, and microelectrophoresis; development of a system for domestic utilization; manufacture of autodistracktoric system pilot models, testing, and preparation of documents for batch production.

Biocompatible hollow capsules have been formed by electrostatic layer-by-layer self-assembly of a perfluorinated ionomer (Nafion) in alternation with ferric ions onto polystyrene latex particles or organic microcrystals, followed by dissolution of the cores by tetrahydrofuran or dimethylformamide. The stepwise growth of multilayers was followed by UV-visible spectroscopy and microelectrophoresis. The formation of hollow capsules was verified by confocal laser scanning microscopy and scanning force microscopy. The hollow Fe3+/Nafion capsules displayed high stability over a wide range of pH values and at high temperature. Fluorescein transport through the Fe3+/Nafion capsule wall was studied by means of photochemical bleaching and recovery (PBR) of the capsule interior. A diffusion model is suggested to calculate the diffusion coefficient for low-molecular-weight species, which was determined to be in the order of 10(-12) cm2s. The permeability can be manipulated by changing the wall thickness of the capsules.