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Using a non-invasive approach, quantitative laser scanning microtomography (QLSM), the morphology of human oocyte was studied layer-by-layer. Then, the cell volume was computed based on 3D reconstruction of a stack of optical sections obtained by QLSM. The integrity of oocyte membrane after cryopreservation was assessed by measuring the changes in oocyte volume in response to hypotonic shock.

The structure of bacterial film formed at the inner surface of the recirculation reactor tube, is studied. The surface relief of the biofilm was visualized by scanning electron microscopy. The effect of electrochemically activated water solution on the film formed from planktonic lactobacteria or E. coli was studied. Treatment with electrochemically activated water solution destroys cells and polymeric matrix of the biofilm.

Analysis of the element composition of oviduct and uterine fluid in mammals showed high potassium concentrations in the early embryo microenvironment in vivo. The results of early embryogenesis of mammals in vitro in the presence of high potassium concentrations are discussed. The data are summarized in accordance with the conditions of experimentally modeled pre-implantation development. Comparative assessment of the quality of embryo development until the blastocyst stage in vitro proved the embryos more successfully developed at potassium concentrations close to those registered in the oviductal fluid.

Regulatory volume decrease in response to hypotonic stress is typical of the oocytes and early mouse embryos. Changes in the kinetics of osmotic reaction can be used as a marker of the modulating effect of the incubation medium on transmembrane transport in embryonic cells. Quantitative laser scanning microtomography (QLSM) was used to measure oocyte volume. In this paper, it is shown that addition of 5 μM glycine, taurine, or GABA, as well as ATP to Dulbecco's medium abolished the regulatory volume decrease in mature mouse oocytes.

The inner surface of the drainage catheter used in surgical interventions for biliary system pathologies was examined by scanning electron microscopy. Microflora in the catheter lumen reflects etiological characteristics of the pathological process and helps to predict possible complications. The developed scanning electron microscopy imaging technique of visualization of the fi ne spatial structure of microbial biofilm formed on the catheter surface allows describing the cell pool and structure of the biofilm.

The surface of wound dressing Biocol was studied by scanning electron microscopy. This composite system consists of latex matrix with incorporated water-soluble polysaccharide. The peculiarities of the surface are important for manufacturing of the dressing and for modification of its surface upon contact with fluids, e.g. during de novo tissue reconstruction. The method for studying the fine structure of the polymeric film surface was developed. The relief of the wound dressing changes during interaction with the fluid and nanopores appear on the surface. Thus, scanning electron microscopy is an informative method for studying the surface of biosynthetic films.

Osmolarity of Dulbecco's medium at which the volume of two-cell mouse embryo remained similar to that of intact embryo was determined. The method is based on comparison of kinetic curves describing the volume of embryonic cell in solutions of different osmolarity. The blastomere volume was measured by quantitative laser microtomography after fixed osmotic stress intervals. It was found that Dulbecco's saline with 125 mM NaCl solution is an isotonic solution for two-cell mouse embryo. This concentration corresponds to 290 mOsm, which is lower than osmolarity (~310 mOsm) of media routinely used for culturing of differentiated cells or biological fluids, e.g. blood plasma.

We performed qualitative comparison of freeze drying and chemical drying as methods of preparing 3D wet specimens for scanning electron microscopy. Human fibroblasts immobilized in collagen gel were used as a model system. Specimens fixed with glutaraldehyde were frozen in liquid nitrogen and freeze-dried at low temperature in high vacuum. In parallel experiments, glutaraldehyde-fixed samples were dehydrated in ascending ethanol solutions, absolute ethanol, and 100% hexamethyldisilazane and then dried at room temperature. Scanning electron microscopy microphotographs of collagen fibers and cells were characterized by high resolution and the absence of collapsed or deformed structures even at high magnification (×50,000) for both chemical drying and high-vacuum freeze drying. However, high-vacuum freeze drying is superior to chemical drying for the investigation of the internal space of 3D scaffolds, because sample fracture can be prepared directly in liquid nitrogen. These techniques are a part of the sample preparation process for scanning electron microscopy and can also be used for studies of cell adhesion, morphology, and arrangement in wet specimens (3D gels and flexible tissue engineering scaffolds).

The blastomer volume was measured by three-dimensional (3D) reconstruction of a series of successive optical sections of the early mouse embryo. Changes in cell volume during osmotic shock were studied. Incubation of a two-cell embryo in Dulbecco's medium induced slow shrinkage of the embryonic cells followed by recovery of its initial volume. A regulatory phase of osmotic shock compensation is characteristic of a blastomer under hypotonic conditions.

The impact of the osmotic component of the incubation medium for the volume of mouse early embryonic cell was studied by laser scanning microscopy. Common Dulbecco's medium caused a prolonged hyperosmotic effect. Adaptive phase of regulatory compensation for the osmotic shock was observed under hypotonic conditions. From these data, water permeability of the blastomer membrane is evaluated as 0.4 micro/(minxatm).

The concentrations of potassium and phosphorus in the cardiomyocyte cytoplasm of the Wistar rat were measured by means of electron probe microanalysis. Pregnancy was accompanied by a decrease in cytoplasmic phosphorus concentration and an increase in cytoplasmic potassium concentration. Acute hypoxia modified the concentrations of these elements in the cytoplasm.

Cytoplasmic Na/K imbalance induced by cytotoxic substances (ethylene glycol and cytochalasin B) was studied. Incubation in Dulbecco's medium with these cytotoxins caused changes in K and Na concentrations in the mouse two-cell embryo blastomer. The effects of both substances resulted in a drop of Na content in the embryonic cell. Washing from cytochalasin B restored the initial Na/K balance in the cytoplasm. Possible adaptive mechanisms involved in the regulation of intracellular ionic homeostasis are discussed.

Administration of substrates of energy metabolism in combination with hypoxen (sulfur-containing oligoquinone) promoted the increase in blood lactate concentration during maximum exercise, accelerated lactate utilization, and reduced the lactate/pyruvate ratio during recovery. The in vivo effects are in line with hypoxen capacity to accelerate in vitro oxidation of exogenous NADH in mitochondria by the non-rotenone-dependent pathway realized with participation of cytochrome C.

Electron probe microanalysis is a method for evaluation of concentrations of elements at the subcellular level, effective in studies of an individual cell in culture or suspension. Intracellular concentrations of cytoplasmic ions (K+, Na+, Cl-) most rapidly and markedly reacting to changes is an adequate criterion for evaluating the traumatism of manipulations used in cell technologies. Using electron probe microanalysis it will be possible to develop special procedures (for example, therapeutic cloning) for reprogramming or cryopreservation, when intactness of intracellular balance of element serves as the criterion of cell status.

The mean potassium and sodium concentrations and distribution of potassium in clonogenic culture of human neural stem cells (neurosphere) were estimated by means of electron probe microanalysis. High sodium concentration was typical of undifferentiated cells. Potassium was irregularly distributed in the test structure. Our results confirm published data on heterogeneous morphological structure of neurospheres.

Comparative analysis of potassium concentrations in the cytoplasm of intact and enucleated one-cell mouse embryos of showed that microsurgical manipulations during collection of pronuclei disordered potassium homeostasis in the embryonic cell.

We propose a method of evaluation of anticlimacteric efficiency of a drug by its effect on the estrous cycle. The study was carried out on 9-month-old mice with retained, but notably reduced reproductive function. Analysis of the cell components of the estrous cycle was carried out on histological preparations of vaginal smears.

The need for effective methods of cryopreservation of early mammalian embryos necessitates the study of the mechanisms of blastomere adaptation to the equilibration procedure and subsequent washing from the cryoprotector. The osmotic effects during these procedures can cause electrolyte imbalance in embryonic cells. Intracellular potassium concentrations at the stage of two-blastomere mouse embryo were studied by electron probe microanalysis.

Direct effects of cardiotropic preparations on the hearts isolated from Wistar rats were examined. Deenergization of cardiomyocytes was modeled under conditions of hypoxic perfusion. Recovery of cardiac function during reperfusion was assessed by changes in the heart rate and contraction amplitude.