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1.
Patol Fiziol Eksp Ter ; (3): 73-5, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25536795

RESUMO

Two examples of tungsten carbide nanoparticles (d = 15 nm, 50 nm) and tungsten carbide nanoparticles with 8% cobalt (d = 50 nm) have been found to induce the neutrophil activation 3 h and 36 h after intraperitoneal administration in the doses 0.005; 0.025; 0.05; 0.25; 0.5; 1; 2.5 and 5 microgram per 1 gram body weight to FVB mice. Neutrophil activation was calculated based on the CD11b and S100 antigen expression. Effect of nanoparticles is bimodal for all tested examples.


Assuntos
Nanopartículas Metálicas , Ativação de Neutrófilo , Neutrófilos/imunologia , Tungstênio/farmacologia , Animais , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Masculino , Camundongos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Peritônio/citologia , Proteínas S100/genética , Proteínas S100/metabolismo
2.
Aviakosm Ekolog Med ; 48(3): 51-5, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25163339

RESUMO

The ultrasonic location technique was used to measure intima-media thickness (IMT), as well as internal systolic diameter of and linear blood velocity in the cervical arteries in people with initial hypertension. Correlation analysis elicited a temporal contingency between these parameters and daily average values of atmospheric pressure. Thus, common carotid artery IMT tended to increase on high-pressure days. Besides, diameters of the common and internal carotid arteries, and vertebral artery were narrowed and, consequently, linear blood velocity in these vessels increased. This relationship is more evident in men than women and in elderly subjects than young. These results are suggestive of a vasoconstrictive action of high atmospheric pressure on these arteries. The relationship is not universal, as it is nonlinear for diameter of the internal carotid artery and inverse for the external one. This implies different sensitivity of arteries to the factor under study and possible blood redistribution in the arterial basin depending on external pressure. The relationship was observed equally on the day of investigation and previous days, which points to its temporal stability.


Assuntos
Pressão Atmosférica , Artérias Carótidas/fisiopatologia , Espessura Intima-Media Carotídea/estatística & dados numéricos , Hipertensão/fisiopatologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Artérias Carótidas/patologia , Feminino , Humanos , Hipertensão/patologia , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Vasoconstrição
3.
Biofizika ; 59(4): 656-65, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25707232

RESUMO

The influence of hydrophilic and hydrophobic properties of the uracil elementary nucleic acids bases on its solubility and structure in aqueous solution was studied. Complexes of uracil with water molecules (from 1 to 14) were then calculated. The geometrical parameters of the hydrogen bridge of uracil and the changes in the frequency of valence vibrations of the bonds participating directly in hydrogen bond formation were calculated. It is shown that for the hydrogen bonds O(w)...HN(1) and O(w)...HN3 the hydrogen atom can tear, it may lead to tautomeric transformation of uracil. The results obtained having calculated the structure of uracil dimers, formed with the hydrogen bonds, in an isolated state and water solution, energy, dipole moments and the hydrogen bridge parameters made it possible to explain low solubility of uracil in water at room temperature. It is shown that water molecules with increase in their number are located mainly at one side of the plane of a pyrimidine uracil ring, that leads to the formation of stacking. Of two possible variants of stacking formation, the most profitable grouping is when a dipole moment of the formed dimer is equal to zero (anti-parallel stacking).


Assuntos
Modelos Químicos , Uracila/química , Água/química , Interações Hidrofóbicas e Hidrofílicas
4.
Biofizika ; 58(5): 841-7, 2013.
Artigo em Russo | MEDLINE | ID: mdl-25481952

RESUMO

In this article the method for studying 3-dimensional (stereological) characteristics of interactions of biological micro objects with nanoparticles on a basis of morphodensitometry analysis of standard 2-dimensional images of cytological and histological specimens is proposed. The performance of the task of determining the distance from registered nanoparticle to the center of the nucleus of the cell is described in detail. It is shown that using specific nanoparticles the results obtained may find application in science and diagnostics. Furthermore, it is possible to employ these results in nanotoxicology, in particular for determination of quantity characteristics of translocation of nanoparticles of different types in biological structures.


Assuntos
Heterocromatina/química , Interfase , Nanopartículas/química , Núcleo Celular/química , Modelos Teóricos
5.
Gig Sanit ; (4): 89-91, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20873393

RESUMO

Estimation of the potential ability of nanoparticles (NP) to affect human health has generated a need for developing rapid, sensitive, and efficient laboratory tests of the toxicity of nanomaterials. The purpose of the investigation was to study the cytotoxic effect of NP of silver (Ag) and silicon dioxide (SiO2). The transplantable Vero cells treated with NP at different concentrations were used as target cells. Some experiments examined the combined effects of nanopowders and herpes simplex virus type 2 (HSV-2) on Vero cell viability and the direct effect of NP on the reproductive potential of HSV-2 in the culture. SiO2 NPs at concentrations of 1.0 to 0.1 mg/ml were found to cause a marked cytotoxic effect that was in the complete destruction of the cell monolayer. Ag HPs were more toxic than silicon nanopowders and induced a complete degradation of the cell monolayer at substantially lower concentrations. The results of the study formed the basis for the development of a rapid (24-48-hour), reliable, and efficient test for the toxicity of nanomaterials, by using the cultured cells in the laboratory setting. It was also shown that silicon NPs did not noticeably affect the reproductive potential of HSV-2 while nano silver suppressed the capacity of HSV-2 for multiplication, by significantly reducing viral progeny titer in the cell culture.


Assuntos
Herpesvirus Humano 2 , Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Prata/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Efeito Citopatogênico Viral , Relação Dose-Resposta a Droga , Herpesvirus Humano 2/efeitos dos fármacos , Herpesvirus Humano 2/fisiologia , Pós , Células Vero , Replicação Viral/efeitos dos fármacos
6.
Artigo em Russo | MEDLINE | ID: mdl-21328903

RESUMO

The present study included 160 patients (206 eyes) presenting with the initial and advanced stages of primary open-angle glaucoma. 120 patients (157 eyes) were treated using biologically controlled ultrasound therapy besides traditional medicamentous therapy, the remaining 40 ones (49 eyes) were given only conventional medication. Results of the treatment were evaluated based on a set of commonly used hydrodynamic and electrophysiological characteristics of the quality of visual function. Biologically controlled massage of trabecular structures of the affected eyes made it possible to stabilize and improve major hydrodynamic characteristics of the eyeball drainage system, visual function, and electrophysiological parameters. Biologically controlled ultrasound therapy proved to produce a more pronounced beneficial effect on ocular hydrodynamics than the traditional ultrasonic treatment. The positive action of biologically controlled therapy persisted during 8 months; its repeated sessions prolonged this period up to 2 years.


Assuntos
Glaucoma de Ângulo Aberto/terapia , Terapia por Ultrassom/métodos , Idoso , Estudos de Avaliação como Assunto , Olho/irrigação sanguínea , Olho/fisiopatologia , Feminino , Glaucoma de Ângulo Aberto/fisiopatologia , Hemodinâmica , Humanos , Masculino , Recuperação de Função Fisiológica , Fatores de Tempo , Visão Ocular
7.
Biofizika ; 54(5): 813-9, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19894618

RESUMO

The parameters of tautomeric equilibrium and stability of lactam-lactim, amino-imino, and N9H <--> N7H tautomeric forms of adenine, purine, guanine, and cytosine for isolated states have been calculated. It was found that the Ade-N9H tautomeric form is most stable; in this case the intramolecular proton transfer and tautomeric transformation Ade-N9H --> Ade-N7H can occur. The parameters of tautomeric equilibrium and stability for seven tautomeric forms of guanine were determined. For cytosine, the simultaneous existence of the amino-hydroxy, imino-oxo and valence amino-hydroxy of tautomeric forms was predicted.


Assuntos
Adenina/química , Citosina/química , Guanina/química , Modelos Químicos , Purinas/química , Hidrogênio/química , Ligação de Hidrogênio
8.
Gig Sanit ; (6): 53-5, 2009.
Artigo em Russo | MEDLINE | ID: mdl-20143490

RESUMO

This paper gives information on the action of nanoparticles when interacting with biological objects and penetrating into them. The high chemical activity of nanoparticles determines their enhanced biological activity against living organisms. Due to their special properties and sizes, the nanoparticles can penetrate across the cell membranes or between the cells and spread to various organs and systems by different mechanisms (endocytosis and transcytosis). In vitro and in vitro investigations of human exposure to nanopowders strongly suggest the occurrence of inflammatory processes, oxidative stresses in the lung and peripheral organs when such powders are inhaled. A few days after intracheal administration, the nanoparticles (30-60 nm in size) penetrate into the cells of the liver, kidney, and gonads and, moreover, primarily impair the mitochondria and penetrate into the nucleus, carrying the viruses on their arms into the cell nucleus. By taking into account the penetrating capacity of nanoparticles into various human organs and tissues and into cell substances, there are a number of problems and questions as both positive in the use of nanoparticles in medicine and other branches of industry as materials that can deliver a drug to the involved organs, by improving the properties of many materials, and negative, such as the development of new forms of abnormalities that are still unknown medicine. In this connection, it is necessary to develop technical regulations on their manufacture, use, storage, transportation, and utilization and those on the realization of various imported materials containing the nanoparticles and obtained by nanotechnologies.


Assuntos
Higiene , Resíduos Industriais/efeitos adversos , Nanoestruturas/efeitos adversos , Exposição Ocupacional/prevenção & controle , Saúde Ocupacional/legislação & jurisprudência , Saneamento/legislação & jurisprudência , Humanos , Exposição Ocupacional/efeitos adversos , Federação Russa
10.
Anal Chem ; 80(7): 2539-47, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18318509

RESUMO

The enumeration of absolute cell numbers and cell proliferation in clinical samples is important for diagnostic and research purposes. Detection of cellular DNA with fluorescent dyes is the most commonly used approach for cell enumeration in cytometry. Inductively coupled plasma mass spectrometry (ICPMS) has been recently introduced to the field of protein and cell surface antigen identification via ICPMS-linked immunoassays using element-labeled affinity reagents such as gold and lanthanide-conjugated antibodies. In the present work, we describe novel methods for using metallointercalators that irreversibly bind DNA and low concentrations of rare earth metals added to cell growth media for rapid and sensitive measurement of cell numbers by mass spectrometry. We show that Ir- and Rh-containing metallointercalators are useful reagents for labeling cells and normalizing signals when studying antigen expression on different types and numbers of cells. Results are presented for solution analysis performed by conventional ICPMS and compared to measurements obtained on the novel flow cytometer mass spectrometer (FC-MS) instrument, designed to analyze multiple antigens and DNA simultaneously in single cells.


Assuntos
Antígenos/análise , Antígenos/química , DNA/análise , DNA/química , Substâncias Intercalantes/química , Espectrometria de Massas/métodos , Antígenos/imunologia , Biomarcadores , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Chumbo/farmacologia , Estrutura Molecular , Paládio/farmacologia , Ródio/farmacologia
11.
Bull Exp Biol Med ; 141(5): 653-6, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-17181076

RESUMO

Rat hepatocytes were examined under electron microscope at early terms after intratracheal administration of highly dispersed silicon dioxide powder against the background of uridine treatment. Penetration of powder particles into hepatocyte cytoplasm, nuclei, mitochondria, and peroxisomes and development of bacteria in these cells were observed. Uridine reduced the destructive effect of powder on the organelles, increased glycogen content in hepatocytes, and inhibited the formation of capsulated bacterial forms in these cells.


Assuntos
Estruturas Celulares/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/ultraestrutura , Dióxido de Silício/toxicidade , Uridina/farmacologia , Animais , Estruturas Celulares/ultraestrutura , Microscopia Eletrônica , Tamanho da Partícula , Ratos , Dióxido de Silício/administração & dosagem , Uridina/administração & dosagem
12.
Phys Rev Lett ; 97(14): 144801, 2006 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-17155264

RESUMO

Volume reflection predicted in the mid-1980s by Taratin and Vorobiev has been observed for the first time in the interactions of a 70 GeV proton beam with a short bent crystal. Incident protons deviate from convex atomic planes in the bulk of the crystal as a result of coherent interaction with bent lattice around the tangency point of particle trajectory with a curved atomic plane. The deflection angle 2theta(R) was found to be (39.5+/-2.0) microrad, or (1.65+/-0.08)theta(c) in terms of the critical angle for channeling. The process has a large probability with respect to channeling and takes place in the angular range equal to the bend angle of atomic planes. It could possibly open new fields of application of crystals in high-energy particle beam optics.

13.
J Immunol Methods ; 308(1-2): 68-76, 2006 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-16336974

RESUMO

There is a great need in cell biology for the simultaneous detection of many intracellular and extracellular proteins within single cells. Current optical methods based on fluorescence activated flow cytometry are difficult to multiplex. We have developed a novel application of ICP-MS-linked metal-tagged immunophenotyping which has great potential for highly multiplexed proteomic analysis. Expression of intracellular oncogenic kinase BCR/Abl, myeloid cell surface antigen CD33, human stem cell factor receptor c-Kit and integrin receptor VLA-4 were investigated using model human leukemia cell lines. Antigens to which specific antibodies are available and are distinguishably tagged can be determined simultaneously, or multiplexed. Four commercially available tags (Au, Sm, Eu, and Tb) conjugated to secondary antibodies enable a 4-plex assay assuming that the primary antibodies are not cross-reactive. Results obtained by ICP-MS were compared with data from FACS. ICP-MS as an analytical detector possesses several advantages that enhance the performance of immunoassays, which are discussed in detail. Although multiplexing using metal-conjugated reagents is in a very early stage of research and feasibility studies, it is already apparent that more than four antigens could be accurately detected simultaneously using the ICP-MS instrument.


Assuntos
Antígenos/análise , Imunofenotipagem/métodos , Espectrometria de Massas/métodos , Animais , Anticorpos Monoclonais , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Linhagem Celular , Separação Celular , Citometria de Fluxo , Proteínas de Fusão bcr-abl/análise , Humanos , Integrina alfa4beta1/análise , Camundongos , Proteínas Proto-Oncogênicas c-kit/análise , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico
14.
Ross Fiziol Zh Im I M Sechenova ; 92(7): 889-901, 2006 Jul.
Artigo em Russo | MEDLINE | ID: mdl-17300046

RESUMO

The chicken chorioallantoic membrane is assessed between days 7 and 20 of incubation using light and electron microscopy with morphometric analysis. The completion of its formation by the middle of embryogenesis is observed, after that a rapid increase in the embryo body mass continues. The bloodstream combines chorionic epithelium, mesoderm, and allantoic epithelium into the single multifunctional organ. The ordered antiparallel arrangement of afferent and efferent vessels within the mesoderm as well as their specialized endothelium assist in partial blood fluid filtration into the interstitium. The unique structure of the capillary network within and over the chorionic epithelium that provide for the effective gas exchange is depicted. It is revealed that the ultrastuctural specialization of the chorionic epithelial cells through which an active calcium transport from the eggshell takes place. The ultrastructure peculiarities of the allantoic epithelium concerning the water-salt balance maintaining in the growing embryo, are discussed.


Assuntos
Embrião de Galinha/crescimento & desenvolvimento , Membrana Corioalantoide/embriologia , Membrana Corioalantoide/ultraestrutura , Animais , Transporte Biológico , Cálcio/metabolismo , Capilares/embriologia , Capilares/fisiologia , Capilares/ultraestrutura , Membrana Corioalantoide/irrigação sanguínea , Endotélio/embriologia , Endotélio/ultraestrutura , Permeabilidade
15.
Bull Exp Biol Med ; 137(6): 556-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15455083

RESUMO

Electron microscopy and cytochemical study of alveolar tissue of rat lungs were performed at the early stage after intratracheal treatment with fine silicon dioxide powder. The preparation was administered to animals receiving or not receiving intravenous injection of uridine. Dust particles permeated the cytoplasm, mitochondria, and nuclei of cells in the air-blood barrier of the alveoli. Uridine decreased the severity of dust-induced damage to cells and increased intracellular glycogen content.


Assuntos
Pulmão , Dióxido de Silício/farmacologia , Uridina/farmacologia , Animais , Pulmão/anatomia & histologia , Pulmão/efeitos dos fármacos , Pulmão/ultraestrutura , Distribuição Aleatória , Ratos , Dióxido de Silício/administração & dosagem , Uridina/administração & dosagem
16.
Aviakosm Ekolog Med ; 36(3): 31-8, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12222069

RESUMO

The effective coefficient of oxygen diffusion in muscle fibers (DO2eff) calculated from measured values of O2 critical pressure, O2 intake and fiber diameter in different skeletal muscles in vertebrates turned to be equal to (0.9-1.8) x 10(-6) cm2/s, which is 11 to 33 times lower than O2 in water. In mature animals, DO2eff reaches this value after the fiber diameter has grown to the maximum. In embryos and developing species with thinner myofibers DO2eff is significantly lower. Variations in oxidative metabolism in the fiber do not change DO2eff. Temperature drop in the fiber by 10 degrees C reduces DO2eff by approximately 30%. Modeling of the oxygen regimes in skeletal muscles with low DO2eff demonstrated that increase of the size of the O2-rich interstitium from 9 up to 25% reduces the diffusive resistance to O2 on the way from the capillary to mitochondria by approximately 20% (1); in combined muscles hypoxic areas may appear in the center of fibers with a high O2 demand, particularly when diameters of these fibers are comparatively large (2); the volumetric blood flow in the muscle can be infinitely large and O2 pressure in veins can remain high (the so-called functional shunting).


Assuntos
Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Oxigênio/metabolismo , Fatores Etários , Animais , Embrião de Galinha/metabolismo , Galinhas/metabolismo , Difusão , Modelos Biológicos , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/crescimento & desenvolvimento , Consumo de Oxigênio , Ratos , Ratos Wistar , Temperatura , Fatores de Tempo
19.
Vopr Virusol ; 47(6): 38-41, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12508683

RESUMO

A method of detection of BLV proviral DNA in the peripheral blood leukocytes of cattle is reported. Leukocytes were used without preliminary cultivation. Cell DNA was dot-hybridized with P-labeled plasmid containing a fragment of BLV proviral DNA. The sera samples taken from the cattle under study were also tested using immunodiffusion assay (ID). The results of comparison showed that dot-hybridization assay is a more sensitive diagnostic test than ID, because it detects BLV infection in apparently normal cattle, which was seronegative in ID.


Assuntos
Leucose Enzoótica Bovina/diagnóstico , Vírus da Leucemia Bovina/isolamento & purificação , Leucócitos/virologia , Provírus/isolamento & purificação , Animais , Anticorpos Antivirais/sangue , Bovinos , Sondas de DNA , DNA Viral/análise , Leucose Enzoótica Bovina/sangue , Leucose Enzoótica Bovina/virologia , Immunoblotting/métodos , Imunodifusão , Vírus da Leucemia Bovina/genética , Hibridização de Ácido Nucleico , Provírus/genética , Sensibilidade e Especificidade
20.
Fresenius J Anal Chem ; 370(5): 454-70, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11496972

RESUMO

A low-level review of the fundamentals of ion-molecule interactions is presented. These interactions are used to predict the efficiencies of collisional fragmentation, energy damping and reaction for a variety of neutral gases as a function of pressure in a rf-driven collision/reaction cell. It is shown that the number of collisions increases dramatically when the ion energies are reduced to near-thermal (< 0.1 eV), because of the ion-induced dipole and ion-dipole interaction. These considerations suggest that chemical reaction can be orders of magnitude more efficient at improving the analyte signal/background ratio than can collisional fragmentation. Considerations that lead to an appropriate selection of type of gas, operating pressure, and ion energies for efficient operation of the cell for the alleviation of spectral interferences are discussed. High efficiency (large differences between reaction efficiencies of the analyte and interference ions, and concomitant suppression of secondary chemistry) might be required to optimize the chemical resolution (determination of an analyte in the presence of an isobaric interference) when using ion-molecule chemistry to suppress the interfering ion. In many instances atom transfer to the analyte, which shifts the analytical m/z by the mass of the atom transferred, provides high chemical resolution, even when the efficiency of reaction is relatively low. Examples are given of oxidation, hydroxylation, and chlorination of analyte ions (V+, Fe+, As+, Se+, Sr+, Y+, and Zr+) to improve the capability of determination of complex samples. Preliminary results are given showing O-atom abstraction by CO from CaO+ to enable the determination of Fe in high-Ca samples.

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