Search

Thin nanocrystalline transparent Al-doped ZnO (1-10 at.% Al) films were synthesized by solid-phase pyrolysis at 700 °C. Synthesized Al-doped ZnO films were investigated by X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM, TEM). All obtained materials were crystallized into the wurtzite structure, which was confirmed by XRD. The material crystallinity decreases with the introduction of aluminum. SEM and TEM showed that the films are continuous and have a uniform distribution of nanoparticles with an average size of 15-20 nm. TEM confirmed the production of Al-doped ZnO films. The transmittance of Al-doped ZnO films in the range of 400-1000 nm is more than 94%. The introduction of 1% Al into ZnO leads to a narrowing of the band gap compared to ZnO to a minimum value of 3.26 eV and a sharp decrease in the response time to the radiation exposure with a wavelength of 400 nm. An increase in aluminum concentration leads to a slight increase in the band gap, which is associated with the Burstein-Moss effect. The minimum response time (8 s) was shown for film containing 10% Al, which is explained by the shortest average lifetime of charge carriers (4 s).

Thin nanocomposite films based on zinc oxide (ZnO) added with cobalt oxide (Co 3 O 4 ) were synthesized by solid-phase pyrolysis. According to XRD, the films consist of a ZnO wurtzite phase and a cubic structure of Co 3 O 4 spinel. The crystallite sizes in the films increased from 18 nm to 24 nm with growing annealing temperature and Co 3 O 4 concentration. Optical and X-ray photoelectron spectroscopy data revealed that enhancing the Co 3 O 4 concentration leads to a change in the optical absorption spectrum and the appearance of allowed transitions in the material. Electrophysical measurements showed that Co 3 O 4 -ZnO films have a resistivity up to 3 × 10 4 Ohm∙cm and a semiconductor conductivity close to intrinsic. With advancing the Co 3 O 4 concentration, the mobility of the charge carriers was found to increase by almost four times. The photosensors based on the 10Co-90Zn film exhibited a maximum normalized photoresponse when exposed to radiation with wavelengths of 400 nm and 660 nm. It was found that the same film has a minimum response time of ca. 26.2 ms upon exposure to radiation of 660 nm wavelength. The photosensors based on the 3Co-97Zn film have a minimum response time of ca. 58.3 ms versus the radiation of 400 nm wavelength. Thus, the Co 3 O 4 content was found to be an effective impurity to tune the photosensitivity of radiation sensors based on Co 3 O 4 -ZnO films in the wavelength range of 400-660 nm.

The widespread use of polymer composite materials (PCM) leads to an increase in non-recyclable waste. This paper discusses the feasibility of recycling fiberglass with an epoxy matrix by solvolysis in ethanol under supercritical conditions. The solvolysis process completes successfully within four hours in an environment of a pure solvent containing 10% water at a temperature of 280 °C when the solvent passes into the supercritical state. The treatment time increases up to 10 h at a process temperature of 250 °C. When using a coordination compound of copper(II) chloride with organic chloride salt having 2,3,5-triphenyltetrazolium as the counterion, having the composition of (2,3,5-triphenyltetrazolium) 2 [CuCl 4 ], the treatment time is reduced. The addition of the complex of 5% by weight makes it possible to completely remove the epoxy matrix at a temperature of 250 °C for two hours. The products separated from the solvolysis liquid were studied by infrared spectroscopy. The resulting fibers were examined by thermogravimetric analysis and scanning electron microscopy. The residual strength of the recovered fibers is 98%. Thus, the resulting fibers can be reused in the composite industry. Including both for the production of decorative products and for the production of structural products made of polymer composite materials.

Gas sensors based on the multi-sensor platform MSP 632, with thin nanocomposite films based on tin dioxide with a low content of zinc oxide (0.5-5 mol.%), were synthesized using a solid-phase low-temperature pyrolysis technique. The resulting gas-sensitive ZnO-SnO 2 films were comprehensively studied by atomic force microscopy, Kelvin probe force microscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy, energy dispersive X-ray spectrometry, and X-ray photoelectron spectroscopy. The obtained films are up to 200 nm thick and consist of ZnO-SnO 2 nanocomposites, with ZnO and SnO 2 crystallite sizes of 4-30 nm. Measurements of ZnO-SnO 2 films containing 0.5 mol.% ZnO showed the existence of large values of surface potential, up to 1800 mV, leading to the formation of a strong surface electric field with a strength of up to 2 × 10 7 V/cm. The presence of a strong surface electric field leads to the best gas-sensitive properties: the sensor's responsivity is between two and nine times higher than that of sensors based on ZnO-SnO 2 films of other compositions. A study of characteristics sensitive to NO 2 (0.1-50 ppm) showed that gas sensors based on the ZnO-SnO 2 film demonstrated a high sensitivity to NO 2 with a concentration of 0.1 ppm at an operating temperature of 200 °C.

Both ATP and inorganic polyphosphates (PolyP) appeared to be involved in the yeast energy homeostasis, in which plasma membrane PMA1 H + -АТРase plays one of the key roles. During biogenesis and functioning, the enzyme undergoes structural and regulatory phosphorylation. Aim of the work was to elucidate interconnection between functioning of the yeast PMA1 H + -АТРase carrying point substitutions that affected the enzyme structure-function relationship and its ability to be phosphorylated and PolyP metabolism. Effect of such replacements of phosphorylable and non-phosphorylable residues in three topologically and functionally different domains of the enzyme - membrane, extracytosolic, and C -terminal - on the metabolism of polyphosphates and distribution between short-, mid-, and long-chained PolyP fractions (PolyP1-PolyP4-5) has been studied. АТРase activity of membrane and most extracytosolic strains was noticeably lower comparing to the wild type. Of these mutants, three substitutions (L801A, E803A, E847A) have not caused significant changes in PolyP content regardless up to twofold drop of the ATPase activity; F796A with four-fold decreased activity has led to noticeable increase of mid-chained PolyP fractions. The most pronounced effect of PolyP redistribution was caused either by removal of potential (S846A, T850A, D851A) or established (S911A) phosphosites in the PMA1 ATPase or by altering type of the established phosphosite (S911D, T912D). Patterns of PolyP fractions for these two groups have significantly differed from each other, occurring in opposite directions for mutants with removed and changed phosphosite. Changing residue of phosphosite without altering its type (T850S) has not led to significant changes in PolyP content.Communicated by Ramaswamy H. Sarma.

Introduction: Currently, the basis for molecular diagnostics of most infections is the use of reverse transcription polymerase chain reaction (RT-PCR). Technologies based on reverse transcription isothermal loop amplification (RT-LAMP) can be used as an alternative to RT-PCR for diagnostic purposes. In this study, we compared the RTLAMP and RT-PCR methods in order to analyze both the advantages and disadvantages of the two approaches., Material and Methods: For the study, we used reagent kits based on RT-PCR and RT-LAMP. The biological material obtained by taking swabs from the mucous membrane of the oropharynx and nasopharynx in patients with symptoms of a new coronavirus infection was used., Results: We tested 381 RNA samples of the SARS-CoV-2 virus (Coronaviridae: Coronavirinae: Betacoronavirus; Sarbecovirus) from various patients. The obtained values of the threshold cycle (Ct) for RT-PCR averaged 20.0 ± 3.7 s (1530 ± 300 s), and for RT-LAMP 12.8 ± 3.7 s (550 ± 160 s). Proceeding from the theoretical assumptions, a linear relationship between values obtained in two kits was proposed as a hypothesis; the correlation coefficient was approximately 0.827. At the same time, for samples with a low viral load (VL), the higher Ct values in RT-LAMP did not always correlated with those obtained in RT-PCR., Discussion: We noted a significant gain in time for analysis using RT-LAMP compared to RT-PCR, which can be important in the context of testing a large number of samples. Being easy to use and boasting short turnaround time, RT-LAMP-based test systems can be used for mass screening in order to identify persons with medium and high VLs who pose the greatest threat of the spread of SARS-CoV-2, while RT-PCR-based diagnostic methods are also suitable for estimation of VL and its dynamics in patients with COVID-19.

Focused ultrasound (FU) is in demand for clinical cancer therapy, but the possible thermal injury to the normal peripheral tissues limits the usage of the ablative FU for tumors with a large size; therefore research efforts have been made to minimize the possible side effects induced by the FU treatment. Non-ablative focused ultrasound assisted chemotherapy could open a new avenue for the development of cancer therapy technology. Here, low intensity focused ultrasound (LIFU) for controlled quick intracellular release of small molecules (Mw ≤ 1000 Da) without acute cell damage is demonstrated. The release is achieved by a composite poly(allylamine hydrochloride) (PAH)/poly-(sodium 4-styrenesulfonate) (PSS)/SiO2 microcapsules which are highly sensitive to LIFU and can be effectively broken by weak cavitation effects. Most PAH/PSS/SiO2 capsules in B50 rat neuronal cells can be ruptured and release rhodamine B (Rh-B) into the cytosol within only 30 s of 0.75 W cm-2 LIFU treatment, as demonstrated by the CLSM results. While the same LIFU treatment shows no obvious damage to cells, as proved by the live/dead experiment, showing that 90% of cells remain alive.

This review presents the basic principles of application of the loop-mediated isothermal amplification (LAMP) reaction for the rapid diagnosis of coronavirus infection caused by SARS-CoV-2. The basic technical details of the method, and the most popular approaches of specific and non-specific detection of amplification products are briefly described. We also discuss the first published works on the use of the method for the detection of the nucleic acid of the SARS-CoV-2 virus, including those being developed in the Russian Federation. For commercially available and published LAMP-based assays, the main analytical characteristics of the tests are listed, which are often comparable to those based on the method of reverse transcription polymerase chain reaction (RT-PCR), and in some cases are even superior. The advantages and limitations of this promising methodology in comparison to other methods of molecular diagnostics, primarily RT-PCR, are discussed, as well as the prospects for the development of technology for the detection of other infectious agents.

Objective - to outline the basic ideas about the conditions and results of the burning of human corpses and the potential possibilities of a forensic medical examination of the burned remains. It is impossible to burn the corpse of an adult to a state of only homogeneous ash not only on the fire, but also in special crematorium chambers. After the burning of the corpse, ash and bone fragments remain in a state of black, gray and white heat. The state of the cremated remains allows, at least, establishing the number of incinerated corpses, their species and anatomical affiliation. Reconstruction of the conditions of corpse burning is possible only within the framework of a comprehensive forensic examination with the participation of specialists in the field of fire-technical affairs and forensic medical experts. The exclusive competence of specialists in the field of fire-technical affairs is the verification of the conditions of combustion (type and volume of fuel, technical features of combustion, duration of cremation, etc.).

High intensity focused ultrasound (HIFU) is widely used in medical practice, including cancer therapy. Also this approach is promising for remote release of encapsulated drugs in various other biomedical applications where local treatment is needed. Our approach underpins the minimization of HIFU impact on possible degradation of biological tissues and expand the use of HIFU in the controlled release of encapsulated drugs. We demonstrated the efficient ultrasound-induced release of labeled protein (Cy7-BSA) from elaborated nanocomposite microcapsules in vitro an in vivo. The capsule fabrication was done using combination of recently developed freezing-induced loading (FIL) technique and Layer-by-Layer assembly (LbL) used for the preparation of complex multilayer BSA/tannic acid nanocomposite capsules sensitive to HIFU. These capsules contain NIR fluorescent Cy7-labeled BSA in the shell for tracking in vivo and the high concentration of labels inside the capsules resulted in self-quenching provides the real-time detection of the protein once it is released from the capsule. Ultrasound-induced release in vivo of Cy7-labeled BSA initially quenched by magnetite nanoparticles was confirmed by fluorescent tomography. The significant decrease of Cy7 fluorescence under HIFU treatment in vitro was found to be due to a generation of reactive oxygen species and fast dye oxidation. Our results demonstrate that adapted HIFU setup can be used for the directed release of encapsulated substances in vivo under tissue compatible NIR monitoring by fluorescent tomography., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Long term encapsulation combined with spatiotemporal release for a precisely defined quantity of small hydrophilic molecules on demand remains a challenge in various fields ranging from medical drug delivery, controlled release of catalysts to industrial anti-corrosion systems. Free-standing individually sealed polylactic acid (PLA) nano- and microchamber arrays were produced by one-step dip-coating a PDMS stamp into PLA solution for 5 s followed by drying under ambient conditions. The wall thickness of these hydrophobic nano-microchambers is tunable from 150 nm to 7 μm by varying the PLA solution concentration. Furthermore, small hydrophilic molecules were successfully in situ precipitated within individual microchambers in the course of solvent evaporation after sonicating the PLA@PDMS stamp to remove air-bubbles and to load the active substance containing solvent. The cargo capacity of single chambers was determined to be in the range of several picograms, while it amounts to several micrograms per cm 2 . Two different methods for sealing chambers were compared: microcontact printing versus dip-coating whereby microcontact printing onto a flat PLA sheet allows for entrapment of micro-air-bubbles enabling microchambers with both ultrasound responsiveness and reduced permeability. Cargo release triggered by external high intensity focused ultrasound (HIFU) stimuli is demonstrated by experiment and compared with numerical simulations.

The state of protective functions of the nasal cavity determines its homeostasis. At the stages of postnatal development and involution of functional parameters by endonasal homeostasis undergo a number of specific changes, the study of which has not only scientific value but also practical value for experimental physiology and clinical medicine. The article presents data on the age dynamics of functional indicators by endonasal homeostasis of human as buffer properties and morphological features of nasal secret. These indicators are examined at the stages of postnatal development in a comparative perspective based on the study of the age gradients and the position of the doctrine of entropy.

Nasal cavity - «the primary line of defense» and a major division of the respiratory tract. A variety of functional areas and regions, structural formations of the nasal cavity allows, at the present stage of development of biology and medicine, consider it as a complex functional subsystem in the structure of the respiratory system. The age transformations of morphological and functional parameters of the nasal cavity are polymorphic and specific. An important aspect of developmental physiology of the respiratory system is a study of the relationship of these changes with morphological and functional transformations of other systems of the body. The article presents the results of the analysis of such contingency-for example, by endonasal correlations with amount of blood flow hemodynamics and functional state of the autonomic nervous system, respiratory function of the nasal cavity and respiratory system, as well as other functions of the nasal cavity and their relationship with general growth processes, critical periods of development and involution. In the process of this analysis revealed a close correlation with complex changes of the morphofunctional parameters of the systems of the human body, most pronounced during in critical periods of postnatal ontogenesis.

The plasma membrane Pma1 H+-ATPase of the yeast Saccharomyces cerevisiae contains conserved residue Asp739 located at the interface of transmembrane segment M6 and the cytosol. Its replacement by Asn or Val (Petrov et al. (2000) J. Biol. Chem., 275, 15709-15716) or by Ala (Miranda et al. (2011) Biochim. Biophys. Acta, 1808, 1781-1789) caused complete blockage of biogenesis of the enzyme, which did not reach secretory vesicles. It was proposed that a strong ionic bond (salt bridge) could be formed between this residue and positively charged residue(s) in close proximity, and the replacement D739A disrupted this bond. Based on a 3D homology model of the enzyme, it was suggested that the conserved Arg811 located in close proximity to Asp739 could be such stabilizing residue. To test this suggestion, single mutants with substituted Asp739 (D739V, D739N, D739A, and D739R) and Arg811 (R811L, R811M, R811A, and R811D) as well as double mutants carrying charge-neutralizing (D739A/R811A) or charge-swapping (D739R/R811D) substitutions were used. Expression of ATPases with single substitutions R811A and R811D were 38-63%, and their activities were 29-30% of the wild type level; ATP hydrolysis and H+ transport in these enzymes were essentially uncoupled. For the other substitutions including the double mutations, the biogenesis of the enzyme was practically blocked. These data confirm the important role of Asp739 and Arg811 residues for the biogenesis and function of the enzyme, suggesting their importance for defining H+ transport determinants but ruling out, however, the existence of a strong ionic bond (salt bridge) between these two residues and/or importance of such bridge for structure-function relationships in Pma1 H+-ATPase.

The problem of age-related functional changes of organs and systems of the human body is one of the urgent problems of modern physiology and gerontology. The most important, complex system of human body is respiratory system, especially its «first line of defense» - the nasal cavity. Functional parameters of the nasal cavity undergo a number of specific changesat the stages of postnatal ontogenesis, the study of which has not only scientific value but also practical value for experimental physiology and clinical medicine. The article presents data on the age dynamics and adaptability of such functional parameters of the mucous membrane of the nasal cavity of the person, as secretory and suction activity, the air heater function, the buffer properties by endonasal secret. These indicators are examined at the stages of postnatal development in a comparative perspective based on the study of the age gradients.

Rapid development of spin noise spectroscopy of the last decade has led to a number of remarkable achievements in the fields of both magnetic resonance and optical spectroscopy. In this report, we demonstrate a new - magnetometric - potential of the spin noise spectroscopy and use it to study magnetic fields acting upon electron spin-system of an n-GaAs layer in a high-Q microcavity probed by elliptically polarized light. Along with the external magnetic field, applied to the sample, the spin noise spectrum revealed the Overhauser field created by optically oriented nuclei and an additional, previously unobserved, field arising in the presence of circularly polarized light. This "optical field" is directed along the light propagation axis, with its sign determined by sign of the light helicity. We show that this field results from the optical Stark effect in the field of the elliptically polarized light. This conclusion is supported by theoretical estimates.

Vascular system of the nasal cavity has a complex structural organization and a wide range of functionality. However, with age, the hemodynamics of the nasal cavity undergoes specific changes, detection of which is of practical importance for gerontology and medicine. This paper presents the results of the study of hemodynamics of the nasal cavity in Mature, elderly and senile age by the method of rheorinography . Identified critical periods of functional changes of blood flow of the nasal cavity: the elderly (exit definitivno state) and old age (involution hemodynamic function and the reduction of its compensatory capacity).

The mucociliary system of the mucosa of the nasal cavity has a complex structural-functional organization and a wide range of functionality. Essential components of this system are the motor activity of ciliated epithelium and mucociliary transport time. With age, the mucous membrane of the nasal cavity undergoes specific changes, detection of which is of practical importance for gerontology and medicine. This article presents the results of studying the main components of the mucociliary apparatus of the nasal cavity of a person in mature, elderly and senile age, we investigated the relationship of functional changes of the mucociliary system with age-related structural reorganization of the epithelial layer of the nasal mucosa. Identified critical periods functional mucociliary system of nasal cavity of man: old age (out of definitivno state) and aging (involution of the mucociliary apparatus).

The goal of this study was to examine the contents of D114 and Jag-1 angiogenesis regulators in human dermis at different age periods. D114 and Jag-1 were demonstrated by indirect immunohistochemistry in skin sections of fetuses of 20-40 gestational weeks and in persons aged from birth to 85 years. D114 was studied in 150 skin samples of 72 females and 78 males, while Jag-1 was examined in 120 samples of 58 females and 62 males. It is found that the immunoreactivity was mainly expressed by the endothelial cells. Vessels, which gave a positive reaction to D114 and Jag-1, were found throughout the entire thickness of the dermis, both in fetuses, and people of all age groups. Expression of D114 in the vessels of dermal microvasculature was shown to increase from 20 weeks of gestation to 20 years. With the further age increase, the intensity of the reaction of blood vessels for D114 was decreased. Expression of Jag-1 in dermal microvessels was enhanced from 20 weeks of gestation to 85 years. The results are discussed in connection with the role of D114 and Jag-1 in angiogenesis in human dermis during ontogeny.

We propose a method of spatial modulation of inhomogeneous broadening of a quantum-well excitonic resonance based on local generation of defects produced by a focused ion beam. The method is applied to fabrication of excitonic diffraction grating in a single quantum-well InGaAs/GaAs structure by irradiating the sample with a beam of 35-keV He + ions of exposure doses <10 12   cm -2 . The spectrum of resonant diffraction on such a structure is narrower than that of reflectivity and decreases much faster with increasing temperature. A proposed model of formation of the diffractive response based on the single scattering approximation well describes the results of the spectral and temperature measurements.

The L5-6 loop is a short extracytoplasmic stretch (714-DNSLDID) connecting transmembrane segments M5 and M6 and forming along with segments M4 and M8 the core through which cations are transported by H+-, Ca2+-, K+,Na+-, H+,K+-, and other P2-ATPases. To study structure-function relationships within this loop of the yeast plasma membrane Pma1 H+-ATPase, alanine- and cysteine-scanning mutagenesis has been employed. Ala and Cys substitutions for the most conserved residue (Leu717) led to complete block in biogenesis preventing the enzyme from reaching secretory vesicles. The Ala replacement at Asp714 led to five-fold decrease in the mutant expression and loss of its activity, while the Cys substitution blocked biogenesis completely. Replacements of other residues did not lead to loss of enzymatic activity. Additional replacements were made for Asp714 and Asp720 (Asp®Asn/Glu). Of the substitutions made at Asp714, only D714N partially restored the mutant enzyme biogenesis and functioning. However, all mutant enzymes with substituted Asp720 were active. The expressed mutants (34-95% of the wild-type level) showed activity high enough (35-108%) to be analyzed in detail. One of the mutants (I719A) had three-fold reduced coupling ratio between ATP hydrolysis and H+ transport; however, the I719C mutation was rather indistinguishable from the wild-type enzyme. Thus, substitutions at two of the seven positions seriously affected biogenesis and/or functioning of the enzyme. Taken together, these results suggest that the M5-M6 loop residues play an important role in protein stability and function, and they are probably responsible for proper arrangement of transmembrane segments M5 and M6 and other domains of the enzyme. This might also be important for the regulation of the enzyme.

Membrane-spanning segments M4, M5, M6, and M8 of the H(+)-, Ca(2+)-, and K(+), Na(+)-ATPases, which belong to the P2-type pumps are the core through which cations are transported. M5 and M6 loop is a short extracytoplasmic stretch of the seven amino acid residues (714-DNSLDID) connecting two of these segments, M5 and M6, where residues involved in the formation of the proton-binding site(s) are located. In the present study, we have used alanine-scanning mutagenesis to explore the structural and functional relationships within this loop of the yeast plasma membrane Pma1 H(+)-ATPase. Of the 7 Ala mutants made, substitution for the most conserved residue (Leu-717) has led to a severe misfolding and complete block in biogenesis of the mutant enzyme. The replacement of Asp-714 has also caused misfolding leading to significant decrease in the expression of the mutant and loss of activity. The remaining mutants were expressed in secretory vesicles at 21-119% of the wild-type level and were active enough to be analyzed in detail. One of these mutants (I719A) showed five- to threefold decrease in both expression and ATP hydrolyzing and H(+) pumping activities and also threefold reduction in the coupling ratio between ATP hydrolysis and H(+) transport. Thus, Ala substitutions at three positions of the seven seriously affected biogenesis, folding, stability and/or functioning of the enzyme. Taken together, these results lead to suggestion that M5 and M6 loop play an important role in the protein stability and function and is responsible for proper arrangement of transmembrane segments M5 and M6 and probably other domains of the enzyme. Results for additional conserved substitutions (Asn and Glu) at Asp-714 and Asp-720 confirmed this suggestion.

Human skin structures stained positively for angiomotin or endostatin were studied by indirect immunohistochemical method. Skin specimens from frontal surface of the lower part of the neck (from upper corner of standard autopsy skin incision) from human fetuses died antenatally from 20 to 40 weeks of pregnancy, humans who died from different causes from 1 day to 85 years of life were obtained at autopsy. Positive staining for angiomotin or endostatin in the skin was found in epidermal cells, fibroblasts, sweat and sebaceous glands, blood vessels of the dermis. Blood vessels stained positively for angiomotin were detected in skin samples in all ages. Age-dependent decrease in the content of angiomotin in blood vessels of the dermis was detected. Most prominent decrease in angiomotin content in dermal blood vessels was found in 61-85 years age-group. Endostatin positive blood vessels were also detected in skin samples of all ages. However, the intensity of staining for endostatin in dermal blood vessels was increased during aging. It can be proposed that changes in the content of angiomotin and endostatin yield a negative impact on angiogenesis in human skin during aging.

Membrane-spanning M5 and M6 segments, which play a role in the formation of cation transport sites in H(+)-, Ca2(+)-, K(+)-, Na(+)-, and other P2-ATPases, are connected by a short extracytoplasmic loop. In the yeast plasma membrane H(+)-ATPase, which belongs to a family of P2-ATPases, the loop is connected to M5 and M6 through the Asp-714 and Asp-720 residues. In this work, the effect of point amino, acidreplacements of Asp-714 and Asp-720 by Ala, Val, Asn, and Glu residues on the function of the enzyme was studied. The Asp714Asn point mutant possessed activities similar to those of the wild-type enzyme, whereas the replacement of Asp-714 by other amino acid residues disrupted biogenesis and led to a loss of activity. All mutants with substitution of Asp-720 were expressed and possessed relatively high activity. The D720V mutant displayed significantly reduced expression levels, activity, H+ transport, and ATP hydrolyzing activity. Thus, substitutions of Asp-714, except for the D714N mutant, led to significant defects in biogenesis and/or function of the enzyme. The results indicate the important role for the Asp-714 residue in biogenesis, structure stability, and enzyme function.

Present research is aimed to examine the number of dermal blood vessels, vascular endothelial growth factor (VEGF), delta-like ligand 4(Dll4) and Jagged-1 (Jag-1) in dermal blood vessels of human from 20weeks of pregnancy to 85years old. Numbers and proliferative activity of dermal fibroblast-like cells were also examined. Blood vessels were viewed with immunohistochemical staining for von Willebrand factor or CD31. VEGF, Dll4, Jag-1, and proliferating cell nuclear antigen (PCNA) were detected immunohistochemically. Results showed that the numbers of fibroblast-like cells, PCNA positive fibroblast-like cells, von Willebrand factor positive or CD31 positive blood vessels in dermis are dramatically decreased with age. The intensity of immunohistochemical staining for VEGF or Jag-1 in blood vessels of dermis is increased from antenatal to deep old period. The degree of immunohistochemical staining of dermal blood vessels for Dll4 has gone up from 20-40weeks of pregnancy to early life period (0-20years), and further decreased below antenatal values. Age-related decrease in the number of dermal blood vessels is suggested to be due to an impairment of VEGF signaling and to be mediated by Dll4 and Jag-1. It may be supposed that diminishing in blood supply of dermis occurring with age is a cause of a decrease in the number and proliferative pool of dermal fibroblasts., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Aims: Differentiation of cardiac fibroblasts (Fbs) into myofibroblasts (MyoFbs) is responsible for connective tissue build-up in myocardial remodelling. We examined MyoFb differentiation and reversibility., Methods and Results: Adult rat cardiac Fbs were cultured on a plastic substratum providing mechanical stress, with conditions to obtain different levels of Fb differentiation. Fb spontaneously differentiated to proliferating MyoFb (p-MyoFb) with stress fibre formation decorated with alpha-smooth muscle actin (α-SMA). Transforming growth factor-β1 (TGF-β1) promoted differentiation into α-SMA-positive MyoFb showing near the absence of proliferation, i.e. non-p-MyoFb. SD-208, a TGF-β-receptor-I (TGF-β-RI) kinase blocker, inhibited p-MyoFb differentiation as shown by stress fibre absence, low α-SMA expression, and high proliferation levels. Fb seeded in collagen matrices induced no contraction, whereas p-MyoFb and non-p-MyoFb induced 2.5- and four-fold contraction. Fb produced little collagen but high levels of interleukin-10. Non-p-MyoFb had high collagen production and high monocyte chemoattractant protein-1 and tissue inhibitor of metalloproteinases-1 levels. Transcriptome analysis indicated differential activation of gene networks related to differentiation of MyoFb (e.g. paxilin and PAK) and reduced proliferation of non-p-MyoFb (e.g. cyclins and cell cycle regulation). Dedifferentiation of p-MyoFb with stress fibre de-polymerization, but not of non-p-MyoFb, was induced by SD-208 despite maintained stress. Stress fibre de-polymerization could also be induced by mechanical strain release in p-MyoFb and non-p-MyoFb (2-day cultures in unrestrained 3-D collagen matrices). Only p-MyoFb showed true dedifferentiation after long-term 3-D cultures., Conclusions: Fb, p-MyoFb, and non-p-MyoFb have a distinct gene expression, ultrastructural, and functional profile. Both reduction in mechanical strain and TGF-β-RI kinase inhibition can reverse p-MyoFb differentiation but not non-p-MyoFb.

A factor that potentially influences on skin aging is blood supply which determines global conditions for an organ or a tissue functioning, including skin. Scientific data on conditions of blood supply in the skin during aging are insufficient and contradictory. Therefore, this work was aimed to the study of age-related changes in the number of blood vessels in the human dermis. Blood vessels were visualized with immunohistochemical technique to two endothelial markers, as von Willebrand factor and antigen CD31. The results showed that von Willebrand factor and antigen CD31 are present in endothelial cells of blood vessels of dermis in all examined age periods, from 20 weeks of pregnancy to 85 yeas. Intensity of immunohistochemical staining to von Willebrand factor is enhanced during age. Intensity of staining to CD31 is not changed with age. The number of blood vessels positively stained either to von Willebrand factor or to CD31 in dermis was decreased gradually with age. A total number of fibroblasts in dermis decreased with age. The number of PCNA+ fibroblasts in dermis showing their proliferative activity was decreased with the progression of age. The decrease in the number of blood vessels is statistically associated with that in the general number of fibroblasts and proliferating fibroblasts. Hence, a factor that leads to aged decrease in the number of dermal fibroblasts is diminished blood supply, and actions targeted to enhancement of blood supply are to be in the basis of clinical approaches to prophylaxis and treatment aging changes of the skin.

In this study, quantitative analysis of inflammatory effectors--mast cells and eosinophils--in derma of people of different ages is performed. The study shows that mast cell quantity in derma increases with age. Eosinophils are rarely observed in human dermis. There are no age-correlated changes of dermal eosinophils quantity observed. Age-correlated dermal fibroblast quantity is established. PCNA+ fibroblast percentage demonstrating their proliferative pool also reliably decreases with age. Results of correlation analysis show that age-correlated increase in mast cells' quantity is reliably correlated with decrease in total number and percentage of PCNA+ fibroblasts in derma. Consequently, age-correlated increase in dermal mast cell may be proposed to be one of the inflammatory and aging mechanisms. Mast cells, whose number increases with aging, may influence dermal fibroblast number with aging.

The aim of this work was the study of age-related changes in the number of CD45+ cells in human dermis. The results showed that the number of CD45+ cells in dermis increased gradually with age. At the same time, a total number of fibroblasts in dermis decreased with age. The number of PCNA+ fibroblasts in dermis showing their proliferative activity was observed to be decreased with the progression of age. The results of the correlation analysis show that the age-related increase of CD45+ cells number is statistically associated with the decrease in the total number of fibroblasts and with the quantity of PCNA+ fibroblasts in dermis through age. Therefore, accumulation of CD45+ cells in human dermis with age may be regarded as a mechanism which brings about inflammatory reaction and emergence of signs of aging. It is also possible that the increased number of bone marrow derived cells has an impact on the age-related decline in the number of fibroblasts in dermis with age.

The crystal structures of the Ca(2+)- and H(+)-ATPases shed light into the membrane embedded domains involved in binding and ion translocation. Consistent with site-directed mutagenesis, these structures provided additional evidence that membrane-spanning segments M4, M5, M6 and M8 are the core through which cations are pumped. In the present study, we have used alanine/serine scanning mutagenesis to study the structure-function relationships within M6 (Leu-721-Pro-742) of the yeast plasma membrane ATPase. Of the 22 mutants expressed and analyzed in secretory vesicles, alanine substitutions at two well conserved residues (Asp-730 and Asp-739) led to a complete block in biogenesis; in the mammalian P-ATPases, residues corresponding to Asp-730 are part of the cation-binding domain. Two other mutants (V723A and I736A) displayed a dramatic 20-fold increase in the IC(50) for inorganic orthovanadate compared to the wild-type control, accompanied by a significant reduction in the K(m) for Mg-ATP, and an alkaline shift in the pH optimum for ATP hydrolysis. This behavior is apparently due to a shift in equilibrium from the E(2) conformation of the ATPase towards the E(1) conformation. By contrast, the most striking mutants lying toward the extracellular side in a helical structure (L721A, I722A, F724A, I725A, I727A and F728A) were expressed in secretory vesicles but had a severe reduction of ATPase activity. Moreover, all of these mutants but one (F728A) were unable to support yeast growth when the wild-type chromosomal PMA1 gene was replaced by the mutant allele. Surprisingly, in contrast to M8 where mutations S800A and E803Q (Guerra et al., Biochim. Biophys. Acta 1768: 2383-2392, 2007) led to a dramatic increase in the apparent stoichiometry of H(+) transport, three substitutions (A726S, A732S and T733A) in M6 showed a reduction in the apparent coupling ratio. Taken together, these results suggest that M6 residues play an important role in protein stability and function, and probably are responsible for cation binding and stoichiometry of ion transport as suggested by homology modeling., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Skin aging is an extremely important medical and social problem in the modern world. Therefore, a goal of the present work was to estimate changes in the numbers of fibroblast-like cells, proliferating cells nuclear antigen-positive cells, CD45-positive cells, mast cells, and eosinophils in human dermis at different ages. Skin specimens from human fetuses that died antenatally from 20 to 40 weeks of pregnancy and humans who died from different causes from 1 day to 85 years of life were used for the study. Results showed a decrease in a total number and the number of proliferating cells nuclear antigen-positive fibroblast-like cells in dermis with progression of age. The numbers of CD45-positive cells and mast cells are gradually increased with aging. Eosinophils are almost absent in dermis independently on age. Mast cells are probably a main factor that potentially can be involved in tissue damage and aging changes in skin. Mast cells should be regarded as an important target for anti-aging therapy.

Skin aging is important medical and social problem in modern world. A goal of present work was to estimate changes in the number of fibroblasts and PCNA-positive fibroblasts in human dermis at different ages. Total number of fibroblasts per unit area was counted in slides stained with haematoxylin and eosin. PCNA which is present in cells being in the cell cycle was revealed immunohistochemically. Results showed a decrease in a total number of fibroblasts in dermis through aging. The number of PCNA-positive fibroblasts in dermis is also decreased with progression of age. It may be concluded that age-related decrease in dermal fibroblasts number is associated with diminished proliferation of these cells. Causes which lead to a decrease in proliferation are not clear, and new researches are needed to reveal them.

Yeast Pma1 H+-ATPase is a key enzyme of cell metabolism generating electrochemical proton gradient across the plasma membrane, thus playing an important role in the maintenance of ion homeostasis in the cell. Using site-directed mutagenesis, we have previously replaced all 21 amino acid residues in the transmembrane segment M8 with Ala (Guerra et al. (2007) Biochim. Biophys. Acta, 1768, 2383-2392). In this work, we present new data on the role of these amino acid residues in the structure-function relationship in the enzyme and cell tolerance to heat shock. Mutations Q798A and I799A are lethal for cells regardless of expression of the enzyme in secretory vesicles or plasma membrane. The F796A mutation causes enzyme and cell sensitivity to heat shock when expressed in secretory vesicles. The I794A mutation increases temperature sensitivity of cells when the enzyme is expressed either in secretory vesicles or, to a lesser extent, in plasma membrane. The E803A mutation has no significant influence on the ATPase and cell sensitivity to heat shock; however, it causes a shift in the equilibrium between E1 and E2 conformations of the enzyme towards E1.

The article presents an experience with application of tension-free plasty of the anterior abdominal wall using reticular endoprostheses. New endoprostheses of Reperen are developed and applied, a method of sutureless fixation of polypropylene net in the abdominal wall tissues is proposed when performing plasty for great ventral hernias. Advantages of new methods are shown compared with analogs both in selective and in emergency surgery, in different age groups of patients. The direct and long-term postoperative results and parameters of quality of life are investigated.

The work presents results of a morphological investigation of tissues in the zone of implantation of synthetic material in creation of experimental model of ventral hernia. A comparative characteristic of a reaction of tissues on reperen and polypropylene is given. A number of principal advantages of reperen as compared with polypropylene were detected in plasty of hernial hilus. An analysis of the first experience of operative treatment of hernias by nonstrain methods using reperen in clinic is made.

Pma1 H+-ATPase is the primary proton pump in the plasma membrane of the yeast Saccharomyces cerevisiae. It generates an electrochemical proton gradient, thus providing energy for secondary solute transport systems. The enzyme contains nine cysteines, three (Cys148, Cys312, and Cys867) in transmembrane segments and the rest (Cys221, Cys376, Cys409, Cys472, Cys532, and Cys569) in the cytosolic parts of the molecule. Although individually they are not essential for the functioning of the ATPase, substitution of all of them leads to the loss of enzyme activity and impairment of biogenesis. By means of site-directed mutagenesis combined with other molecular-biological and biochemical methods, this work defines different combinations of minimal cysteine content that are consistent with ATPase function.

Silver ions induce the efflux of potassium from cells of the yeast Saccharomyces cerevisiae but have no such effect on spheroplasts. Copper ions and the natural fungicide 2-O-3-hydroxyhexanoyl-beta-D-glucopyranosyl-(1-->4)-(6-O-acetyl-beta-D-glucopyranosyl-(1-->16)-2,15,16-trihydroxyhexadecanoic acid) induce the efflux of potassium ions from both cells and spheroplasts of S. cerevisiae. Silver and copper ions inhibit the activity of the plasma membrane H+-ATPase during the treatment of both cells and spheroplasts. It is supposed that the inability of silver ions to stimulate potassium efflux from spheroplasts results from damage to some components of K+ transport systems during preparation of spheroplasts.

TGF-beta1 induces differentiation and total inhibition of cardiac MyoFb cell division and DNA synthesis. These effects of TGF-beta1 are irreversible. Inhibition of MyoFb proliferation is accompanied with the expression of Smad1, Mad1, p15Ink4B and total inhibition of telomerase activity. Surprisingly, TGF-beta1-activated MyoFbs are growth-arrested not only at G1-phase but also at S-phase of the cell cycle. Staining with TUNEL indicates that these cells carry DNA damages. However, the absolute majority of MyoFbs are non-apoptotic cells as established with two apoptosis-specific methods, flow cytometry and caspase-dependent cleavage of cytokeratin 18. Expression in MyoFbs of proliferative cell nuclear antigen even in the absence of serum confirms that these MyoFbs perform repair of DNA damages. These results suggest that TGF-beta1-activated MyoFbs can be growth-arrested by two checkpoints, the G1/S checkpoint, which prevents cells from entering S-phase and the intra-S checkpoint, which is activated by encountering DNA damage during the S phase or by unrepaired damage that escapes the G1/S checkpoint. Despite carrying of the DNA damages TGF-beta1-activated MyoFbs are highly functional cells producing lysyl oxidase and contracting the collagen matrix.

Of the four transmembrane helices (M4, M5, M6, and M8) that pack together to form the ion-binding sites of P(2)-type ATPases, M8 has until now received the least attention. The present study has used alanine-scanning mutagenesis to map structure-function relationships throughout M8 of the yeast plasma-membrane H(+)-ATPase. Mutant forms of the ATPase were expressed in secretory vesicles and at the plasma membrane for measurements of ATP hydrolysis and ATP-dependent H(+) pumping. In secretory vesicles, Ala substitutions at a cluster of four positions near the extracytoplasmic end of M8 led to partial uncoupling of H(+) transport from ATP hydrolysis, while substitution of Ser-800 (close to the middle of M8) by Ala increased the apparent stoichiometry of H(+) transport. A similar increase has previously been reported following the substitution of Glu-803 by Gln (Petrov, V. et al., J. Biol. Chem. 275:15709-15718, 2000) at a position known to contribute directly to Ca(2+) binding in the Ca(2+)-ATPase of sarcoplasmic reticulum (Toyoshima, C., et al., Nature 405: 647-655, 2000). Four other mutations in M8 interfered with H(+)-ATPase folding and trafficking to the plasma membrane; based on homology modeling, they occupy positions that appear important for the proper bundling of M8 with M5, M6, M7, and M10. Taken together, these results point to a key role for M8 in the biogenesis, stability, and physiological functioning of the H(+)-ATPase.

The possibility of using Daphnia magna (Straus) hydrobionts as a test object in modeling the disturbances of dopaminergic neurotransmission was investigated. The toxic action of a selective dopaminergic neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), on D. magna was determined in a broad interval of concentrations (from 2 x 10(-5) to 10(-2) M). Plots of the real time of daphnia death versus MPTP concentration are presented and the concentration limits of its specific activity are evaluated. Experiments on daphnia under the conditions of MPTP intoxication were used to study the modulating effects of drugs producing a pharmacological correction of dopamine secretion disturbances in mammals. It is shown that the exogenous dopamine, muscarinic cholinoblocker pentifine, and antioxidant unithiol exhibit a protective action. Reduced glutathione does not possess protective properties. It is suggested to use D. magna as a simple and informative test object for the modeling of dopaminergic transmission deficiency and for the primary screening of various substances intended for the pharmacological correction of dopamine transmission disturbances.

The review is dedicated to an important multidiscipline problem, nasal bleeding (NB). The presented analysis of Russian and foreign literature on the most important aspects of the problem shows the variety and complexity of the leading pathogenetic mechanisms of NB (the condition of hemostatic and lipid peroxidation systems, the activity of biologically active substances and the kinine system, the condition of local and system blood flow), contradictoriness of data on some aspects, and insufficient knowledge of a range of aspects. The collected data on the pathogenetic mechanisms of NB, despite the high quality of some studies, do not suggest the existence of a common modern theoretical base on this problem.