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1.
Nature ; 537(7621): 515-517, 2016 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-27487219

RESUMEN

Remote observations of the asteroid (1) Ceres from ground- and space-based telescopes have provided its approximate density and shape, leading to a range of models for the interior of Ceres, from homogeneous to fully differentiated. A previously missing parameter that can place a strong constraint on the interior of Ceres is its moment of inertia, which requires the measurement of its gravitational variation together with either precession rate or a validated assumption of hydrostatic equilibrium. However, Earth-based remote observations cannot measure gravity variations and the magnitude of the precession rate is too small to be detected. Here we report gravity and shape measurements of Ceres obtained from the Dawn spacecraft, showing that it is in hydrostatic equilibrium with its inferred normalized mean moment of inertia of 0.37. These data show that Ceres is a partially differentiated body, with a rocky core overlaid by a volatile-rich shell, as predicted in some studies. Furthermore, we show that the gravity signal is strongly suppressed compared to that predicted by the topographic variation. This indicates that Ceres is isostatically compensated, such that topographic highs are supported by displacement of a denser interior. In contrast to the asteroid (4) Vesta, this strong compensation points to the presence of a lower-viscosity layer at depth, probably reflecting a thermal rather than compositional gradient. To further investigate the interior structure, we assume a two-layer model for the interior of Ceres with a core density of 2,460-2,900 kilograms per cubic metre (that is, composed of CI and CM chondrites), which yields an outer-shell thickness of 70-190 kilometres. The density of this outer shell is 1,680-1,950 kilograms per cubic metre, indicating a mixture of volatiles and denser materials such as silicates and salts. Although the gravity and shape data confirm that the interior of Ceres evolved thermally, its partially differentiated interior indicates an evolution more complex than has been envisioned for mid-sized (less than 1,000 kilometres across) ice-rich rocky bodies.

2.
Ter Arkh ; 93(8): 841-852, 2021 Aug 15.
Artículo en Ruso | MEDLINE | ID: mdl-36286877

RESUMEN

Treatment of inflammatory bowel diseases IBD (Crohns disease, ulcerative colitis) is aimed at achieving clinical, endoscopic and histological remission, minimizing surgical complications, and ensuring a normal quality of life. However, the use of medical treatment is potentially associated with various adverse events, among which infectious complications, malignant neoplasms, as well as myelotoxicity, hepatotoxicity, skin lesions and others. The risk of side effects depends on the type of drug therapy (5-aminosalicylates, thiopurines, biologicals, etc.), the duration of treatment, the presence of extra-intestinal manifestations, etc. The article provides an overview of data on both the effectiveness and frequency of various side effects of the main classes of drugs in IBD, presents methods of investigation which can predict the effectiveness and development of side effects, the implementation of which can be considered as a variant of personalized therapy in IBD.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Humanos , Calidad de Vida , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/complicaciones , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/complicaciones , Enfermedad de Crohn/tratamiento farmacológico , Administración de la Seguridad
3.
Molecules ; 25(13)2020 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-32605031

RESUMEN

Cerium oxide nanoparticles (nanoceria) are believed to be the most versatile nanozyme, showing great promise for biomedical applications. At the same time, the controlled intracellular delivery of nanoceria remains an unresolved problem. Here, we have demonstrated the radioprotective effect of polyelectrolyte microcapsules modified with cerium oxide nanoparticles, which provide controlled loading and intracellular release. The optimal (both safe and uptake efficient) concentrations of ceria-containing microcapsules for human mesenchymal stem cells range from 1:10 to 1:20 cell-to-capsules ratio. We have revealed the molecular mechanisms of nanoceria radioprotective action on mesenchymal stem cells by assessing the level of intracellular reactive oxygen species (ROS), as well as by a detailed 96-genes expression analysis, featuring genes responsible for oxidative stress, mitochondrial metabolism, apoptosis, inflammation etc. Hybrid ceria-containing microcapsules have been shown to provide an indirect genoprotective effect, reducing the number of cytogenetic damages in irradiated cells. These findings give new insight into cerium oxide nanoparticles' protective action for living beings against ionising radiation.


Asunto(s)
Cerio/química , Nanopartículas/química , Estrés Oxidativo/efectos de los fármacos , Protectores contra Radiación/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Cápsulas/química , Cápsulas/efectos de la radiación , Línea Celular , Cerio/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/efectos de la radiación , Humanos , Inflamación/tratamiento farmacológico , Inflamación/patología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de la radiación , Mitocondrias/efectos de los fármacos , Mitocondrias/efectos de la radiación , Nanopartículas/efectos de la radiación , Estrés Oxidativo/efectos de la radiación , Polielectrolitos/química , Polielectrolitos/farmacología , Radiación Ionizante , Protectores contra Radiación/química , Especies Reactivas de Oxígeno/química
4.
J Biol Phys ; 45(4): 317-334, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31595390

RESUMEN

This paper examines the effect of electromagnetic waves, with maxima in the green or red regions of the spectrum, on the morphofunctional state of multipotent mesenchymal stromal cells. The illumination regimes used in our experiments did not lead to any substantial heating of the samples; the physical parameters of the lighting were carefully monitored. When the samples were illuminated with a green light, no significant photostimulatory effect was observed. Red light, on the other hand, had an evident photostimulatory effect. It is shown that photostimulation with a red light decreases the enzymatic activities of mitochondrial dehydrogenases and enhances the viability of cells, their proliferative activity, and their ability to form bone tissue. It is also established that red light stimulates cell proliferation, while not activating the genes that increase the risk of the subsequent malignant transformation of cells or their death. This paper discusses the possible role of hydrogen peroxide in the processes examined.


Asunto(s)
Fenómenos Electromagnéticos , Luz , Células Madre Mesenquimatosas/efectos de la radiación , Animales , Proliferación Celular/efectos de la radiación , Color , Regulación de la Expresión Génica/efectos de la radiación , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones
5.
Bull Exp Biol Med ; 162(2): 252-254, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27905033

RESUMEN

The distribution of iron-carbon nanoparticles in FeC-DSPE-PEG-2000 modification (micellar particles with structure (Fe) core-carbon shell; PEG-based coating) is studied. The greater part of the nanoparticles accumulated in the spleen and liver, a small amount in the lungs, and the minimum amount in the thymus. The structural changes in the lymphoid organs were minor and involved only the microcirculatory bed. Analysis of the peripheral blood showed manifest anemia, thrombocytopenia, and leukocytosis.


Asunto(s)
Carbono/farmacocinética , Portadores de Fármacos/farmacocinética , Hierro/farmacocinética , Nanopartículas de Magnetita/química , Animales , Carbono/metabolismo , Eosina Amarillenta-(YS) , Hematoxilina , Histocitoquímica , Hierro/metabolismo , Hígado/efectos de los fármacos , Hígado/ultraestructura , Pulmón/efectos de los fármacos , Pulmón/ultraestructura , Fosfatidiletanolaminas/química , Polietilenglicoles/química , Ratas , Ratas Wistar , Bazo/efectos de los fármacos , Bazo/ultraestructura , Timo/efectos de los fármacos , Timo/ultraestructura , Distribución Tisular
6.
Bull Exp Biol Med ; 158(3): 388-92, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25573374

RESUMEN

Integration of fetal hippocampal dentate fascia neurotransplants with the neocortical somatosensory region in adult rats was studied by electron microscopy. The growth of nerve fiber through the neurotransplant/brain border formed by the glial cells was studied. The interface zone was organized by various astrocyte subpopulations and ependymocytes forming multilamellar accumulations in some sites of the interface. These conglomerations of the glial cells and their processes did not prevent the growth of axonal and axodendritic bundles; moreover, fibrous astrocyte axons accompanied them. Under conditions of immature nervous tissue transplantation to the focus of mature brain damage, the glial cells created a substrate in the interface permeable for nerve fibers, thus promoting the functional integration of the neurotransplant.


Asunto(s)
Encéfalo/citología , Neuroglía/citología , Animales , Axones/ultraestructura , Encéfalo/ultraestructura , Masculino , Microscopía Electrónica , Neuroglía/ultraestructura , Ratas , Ratas Wistar
7.
Bull Exp Biol Med ; 159(4): 498-501, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26395633

RESUMEN

We studied new magnetic nanocomposites consisting of a core(Fe) and carbon-shell inert to biological media. Iron-carbon nanoparticles circulate in the bloodstream for several minutes and are primarily accumulated in the liver; less intensive accumulation was found in the spleen and minimum in the lungs, kidneys, and heart. Accumulation of nanoparticles in the liver leads to the development of destructive processes and is accompanied by activation of compensatory-adaptive mechanisms. In the liver and spleen, structural changes are mild and mainly relate to changes in the microvasculature. In 6 months, the total content of nanoparticles in all tissues decreased due to their elimination from the body and the structure of the organs returned to normal.


Asunto(s)
Portadores de Fármacos/farmacocinética , Nanopartículas de Magnetita/química , Nanocompuestos/química , Animales , Animales no Consanguíneos , Portadores de Fármacos/química , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Ratones , Distribución Tisular
8.
Ontogenez ; 46(6): 365-84, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26859965

RESUMEN

Externally, vertebrates are bilaterally symmetrical; however, left-right asymmetry is observed in the structure of their internal organs and systems of organs (circulatory, digestive, and respiratory). In addition to the asymmetry of internal organs (visceral), there is also functional (i.e., asymmetrical functioning of organs on the left and right sides of the body) and behavioral asymmetry. The question of a possible association between different types of asymmetry is still open. The study of the mechanisms of such association, in addition to the fundamental interest, has important applications for biomedicine, primarily for the understanding of the brain functioning in health and disease and for the development of methods of treatment of certain mental diseases, such as schizophrenia and autism, for which the disturbance of left-right asymmetry of the brain was shown. To study the deep association between different types of asymmetry, it is necessary to obtain adequate animal models (primarily animals with inverted visceral organs, situs inversus totalis). There are two main possible approaches to obtaining such model organisms: mutagenesis followed by selection of mutant strains with mutations in the genes that affect the formation of the left-right visceral asymmetry and experimental obtaining of animals with inverted internal organs. This review focuses on the second approach. We describe the theoretical models for establishing left-right asymmetry and possible experimental approaches to obtaining animals with inverted internal organs.


Asunto(s)
Tipificación del Cuerpo/genética , Modelos Animales , Vertebrados/anatomía & histología , Vísceras , Animales , Tipificación del Cuerpo/efectos de los fármacos , Embrión no Mamífero/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Desarrollo Embrionario/genética , Lateralidad Funcional/efectos de los fármacos , Lateralidad Funcional/genética , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Morfogénesis/efectos de los fármacos , Morfogénesis/genética , Vertebrados/embriología , Vertebrados/genética , Vísceras/efectos de los fármacos , Vísceras/embriología
9.
Gig Sanit ; 94(5): 31-6, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26625612

RESUMEN

The monitoring of snow cover pollution by heavy metals and elements (zinc, copper, lead, cadmium, arsenic, nickel, chromium, strontium, manganese, fluorine, lithium) was performed in 20 districts of the Moscow region in 2009, 2012 and 2013. The assessment of the levels of contamination by heavy metals and elements was given by means of comparison of them with the average values in the snow cover near Moscow in the end of the last century and in some areas of the world, that no exposed to technological environmental impact. 7 districts of Moscow region were characterized by a high content of lead and cadmium in the snow water. It requires the control of water, soil and agricultural products pollution.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Nieve/química , Contaminantes del Suelo/análisis , Agricultura , Metales Pesados/química , Moscú , Contaminantes del Suelo/química , Solubilidad
10.
Klin Lab Diagn ; 60(4): 23-6, 39, 2015 Apr.
Artículo en Ruso | MEDLINE | ID: mdl-26189287

RESUMEN

The endothelium dysfunction takes leading place in pathogenesis of development of cardiovascular diseases. The circulating endothelium cells of peripheral blood can act as a direct cell marker of damage and remodeling of endothelium. The study was carried out to develop a new approach to diagnose of endothelium dysfunction by force of determination of number of circulating endothelium cells using flow cytometry technique and to apply determination of circulating endothelium cells for evaluation of risk of development of ischemic heart disease in women of young and middle age. The study embraced 62 female patients with angiography confirmed ischemic heart disease, exertional angina pectoris at the level of functional class I-II (mean age 51 ± 6 years) and 49 women without anamnesis of ischemic heart disease (mean age 52 ± 9 years). The occurrence of more than three circulating endothelium cells by 3 x 105 leukocytes in peripheral blood increases relative risk of development of ischemic heart disease up to 4 times in women of young and middle age and risk of development of acute myocardial infarction up to 8 times in women with ischemic heart disease. The study demonstrated possibility to apply flow cytometry technique to quantitatively specify circulating endothelium cells in peripheral blood and forecast risk of development of ischemic heart disease in women of young and middle age depending on level of circulating endothelium cells.


Asunto(s)
Angina de Pecho , Células Endoteliales , Endotelio Vascular , Citometría de Flujo/métodos , Isquemia Miocárdica , Adulto , Anciano , Angina de Pecho/sangre , Angina de Pecho/patología , Células Endoteliales/metabolismo , Células Endoteliales/patología , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Femenino , Humanos , Persona de Mediana Edad , Isquemia Miocárdica/sangre , Isquemia Miocárdica/patología
11.
Biofizika ; 59(3): 552-7, 2014.
Artículo en Ruso | MEDLINE | ID: mdl-25715600

RESUMEN

Using inhibitory analysis the role of some intracellular signaling pathways in activation of planarian regeneration under the influence of low-temperature argon plasma (LTAP) has been investigated. Inactivation of specific inhibitors of intracellular signaling enzymes such as the receptor tyrosine kinase (EGFR), TGF ß receptor, calmodulin, adenylate cyclase, phospholipase A2, phospholipase C, cyclin-dependent protein kinase, JAK2-protein kinase, JNK-protein kinase MEK-protein kinase led to inhibition of the head growth during its regeneration in planarians. Pretreatment with LTAP irradiation provided no inhibitory action of some cascades regulating proliferation. However, the inhibitors of the key regulators of regeneration: TGF ß receptor, calmodulin and MEK-protein kinase completely suppressed the activating effect of plasma. Thus, by the example of regenerating planarians it is shown, that biological activity of low-temperature argon plasma LTAP is caused by modulation of a plurality of cellular signaling systems.


Asunto(s)
Argón , Proliferación Celular , Planarias/citología , Planarias/metabolismo , Regeneración , Transducción de Señal , Animales
12.
Ontogenez ; 45(5): 355-60, 2014.
Artículo en Ruso | MEDLINE | ID: mdl-25752153

RESUMEN

Possible involvement of MEK mitogen-activated protein kinase and TGF-ß receptor in the processes of regeneration and morphogenesis in freshwater planarian flatworms Schmidtea mediterranea was studied using a pharmacological inhibitor analysis. It was found that pharmacological inhibitors of these kinases significantly inhibit the regeneration of the head end of the animals and that this effect is realized due to inhibition of proliferative activity of neoblasts, planarian stem cells. It is shown that that the inhibition of the studied protein kinases in regenerating planarians markedly disturbs stem cell differentiation and morphogenesis.


Asunto(s)
Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/fisiología , Planarias/fisiología , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Receptores de Factores de Crecimiento Transformadores beta/fisiología , Regeneración/fisiología , Animales , Flavonoides/farmacología , Planarias/enzimología , Planarias/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/farmacología , Pirroles/farmacología , Regeneración/efectos de los fármacos
13.
Gig Sanit ; (5): 88-94, 2014.
Artículo en Ruso | MEDLINE | ID: mdl-25831937

RESUMEN

Monitoring of snow cover pollution as an indicator of ambient air pollution in 20 districts in the Moscow region during 2009-2013 was performed. The identification with a quantitative assessment of a wide array of organic compounds and the control of the main physical and chemical and inorganic indices of snow water pollution were carried out. More than 60 organic substances for most of which there are no the hygienic standards were established. The assessment of pollution levels of basic inorganic indices was given by means of the comparing them with the average values in the snow cover in the European territory of Russia and natural content in areas not been exposed to human impact.


Asunto(s)
Aldehídos/análisis , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Ácidos Grasos/análisis , Ácidos Ftálicos/análisis , Nieve/química , Aldehídos/química , Cationes/análisis , Cationes/química , Fenómenos Químicos , Contaminantes Ambientales/química , Ácidos Grasos/química , Moscú , Ácidos Ftálicos/química
14.
Acta Naturae ; 16(1): 48-58, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38698963

RESUMEN

Acute myeloid leukemia (AML) is a malignant neoplasm characterized by extremely low curability and survival. The inflammatory microenvironment and maturation (differentiation) of AML cells induced by it contribute to the evasion of these cells from effectors of antitumor immunity. One of the key molecular effectors of immune surveillance, the cytokine TRAIL, is considered a promising platform for developing selective anticancer drugs. Previously, under in vitro conditions of the inflammatory microenvironment (a three-dimensional high-density culture of THP-1 AML cells), we demonstrated the emergence of differentiated macrophage-like THP-1ad clones resistant to TRAIL-induced death. In the present study, constitutive activation of proinflammatory signaling pathways, associated transcription factors, and increased expression of the anti-apoptotic BIRC3 gene were observed in TRAIL-resistant macrophage-like THP-1ad AML cells. For the first time, a bioinformatic analysis of the transcriptome revealed the main regulator, the IL1B gene, which triggers proinflammatory activation and induces resistance to TRAIL in THP-1ad macrophage-like cells.

15.
Ontogenez ; 44(5): 341-56, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-25434203

RESUMEN

During individual development of vertebrates, the anteroposterior, dorsoventral, and left-right axes of the body are established. Although the vertebrates are bilaterally symmetric outside, their internal structure is asymmetric. Of special interest is the insight into establishment of visceral left-right asymmetry in mammals, since it has not only basic but also an applied medical significance. As early as 1976, it was hypothesized that the ciliary action could be associated with the establishment of left-right asymmetry in mammals. Currently, the majority of researchers agree that the ciliary action in the region of Hensen's node and the resulting leftward laminar fluid flow play a key role in the loss of bilateral symmetry and triggering of expression of the genes constituting the Nodal-Ptx2 signaling cascade, specific of the left side of the embryo. The particular mechanism underlying this phenomenon is still insufficiently clear. There are three competing standpoints on how leftward fluid flow induces expression of several genes in the left side of the embryo. The morphogen gradient hypothesis postulates that the leftward flow creates a high concentration of a signaling biomolecule in the left side of Hensen's node, which, in turn, stimulates triggering of.gene expression of the Nodal-Ptx2 cascade. The biomechanical hypothesis (or two-cilia model) states that the immotile cilia located in the periphery of Hensen's node act as mechanosensors, activate mechanosensory ion channels, and trigger calcium signaling in the left side of the embryo. Finally, the "shuttle-bus model" holds that leftward fluid flow carries the lipid vesicles, which are crashed when colliding immotile cilia in the periphery of Hensen's node to release the contained signaling biomolecules. It is also noteworthy that the association between the ciliary action and establishment of asymmetry has been recently discovered in representatives of the lower invertebrates. In this paper, the author considers evolution of concepts on the mechanisms underlying establishment of visceral left-right asymmetry since 1976 until the present and critically reexamines the current concepts in this field of science. According to the author, serious arguments favoring the biomechanical hypothesis for determination of left-right asymmetry in mammals have been obtained.


Asunto(s)
Embrión de Mamíferos/embriología , Regulación del Desarrollo de la Expresión Génica/fisiología , Modelos Biológicos , Morfogénesis/fisiología , Transducción de Señal/fisiología , Animales , Cilios/metabolismo , Humanos , Proteína Nodal/metabolismo
16.
Klin Lab Diagn ; (4): 30-2, 2013 Apr.
Artículo en Ruso | MEDLINE | ID: mdl-23984552

RESUMEN

The article presents the results of clinical economic analysis providing the evaluation of implementation of immunologic examination of patients with chronic infectious inflammatory diseases. To calculate the clinical economic indicators the factor costs and indirect costs were determined in case of immunologic examination and without examination according the data of prospective (80 patients) and retrospective study (500 outpatient cards). To evaluate the significance of approach based on immunologic examination methods the percentage of patients with relapse-free period was calculated. The clinical economic evaluation of methods of diagnostic and treatment made it possible to determine economic advantages of application of immunologic methods of examination independently of localization of chronic torpid process and to assess relationship between costs of immunologic methods of examination and effectiveness of applied treatment.


Asunto(s)
Enfermedad Crónica/economía , Análisis Costo-Beneficio , Infecciones/economía , Humanos , Inmunidad , Infecciones/inmunología , Estudios Prospectivos , Estudios Retrospectivos
17.
Artículo en Ruso | MEDLINE | ID: mdl-22567988

RESUMEN

Behavior and brain electrical activity of 79 male Wistar rats (intact and with acute experimental brainstem injury) were studied during the course of therapeutic transcranial electromagnetic stimulation (TEMS) with frequencies 60 and 70 Hz. In intact animals this effect was accompanied by a decrease in voluntary motor activity and increase in synchronization of the brain electrical activity, in particular, in the delta and beta1 frequency ranges. This inhibitory effect was similar to that of sleep. In the early period of acute experimental stem pathology, the TEMS course was accompanied by suppression of EEG signs of adaptive post-operative stress response and could lead to increased severity of the condition of an animal, along with the slowing of postoperative recovery. Cytomorphological evidence was obtained to the importance of vascular factor in the formation of cerebral reactions to TEMS.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Tronco Encefálico/lesiones , Tronco Encefálico/fisiopatología , Terapia por Estimulación Eléctrica , Recuperación de la Función/fisiología , Estimulación Magnética Transcraneal , Núcleo Vestibular Lateral/fisiopatología , Animales , Ritmo beta/fisiología , Encéfalo/fisiopatología , Lesiones Encefálicas/terapia , Ritmo Delta/fisiología , Masculino , Actividad Motora/fisiología , Plasticidad Neuronal/fisiología , Ratas , Ratas Wistar
18.
Gig Sanit ; (1): 78-81, 2012.
Artículo en Ruso | MEDLINE | ID: mdl-22712335

RESUMEN

The authors have developed the optimal temperature-time parameters of electrothermal atomic absorption determination of arsenic in plants after their acid predigestion. The matrix modifier is 1% nickel nitrate or palladium nitrate solution. Cuvettes (ovens) are simple, made of porous or pyrolytic graphite. The analytical program is suitable for both spectrometers with Zeeman and deuterium background correction. The correctness of the procedure has been estimated from the results of analysis of state reference samples certified for their arsenic content. The coefficient of variation was 20-35% for the concentration range of 0.02-0.2 mg/kg.


Asunto(s)
Arsénico/análisis , Contaminación de Alimentos/análisis , Plantas Comestibles/química , Espectrofotometría Atómica/métodos , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/métodos , Límite de Detección , Poaceae/química , Estándares de Referencia , Semillas/química , Solanum tuberosum/química , Espectrofotometría Atómica/instrumentación , Triticum/química
19.
Her Russ Acad Sci ; 92(4): 491-496, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36091853

RESUMEN

The publications on animal coronavirus infections that have the greatest emerging potential, as well as official data from the World Organization for Animal Health (OIE) on cases of animal infection with COVID-19, are analyzed. Like most infectious diseases common to humans, coronavirus infections were first discovered in animals. Due to the increased rate of replication and recombination activity compared to other viruses, mutations occur more often in the genome of coronaviruses, which contribute to the acquisition of new qualities in order to consolidate in the host organism. Examples of cross-species transmission are not only SARS-CoV, MERS-CoV, and SARS-CoV-2, which are dangerous to humans, but also coronaviruses of agricultural and domestic animals, between which there is a genetic relationship. There are several known cases of zoo, wild, domestic, and farm animals displaying symptoms characteristic of COVID-19 and identification of the genome of the SARS-CoV-2 virus in them. The issue of cross-species transmission of coronavirus infections, in particular the reverse zoonosis of SARS-CoV-2 from animals to humans, is widely discussed. According to the conclusions of many researchers, including OIE experts, there is no direct evidence base for infection of humans with COVID-19 from animals. However, people with suspected COVID-19 and with a confirmed diagnosis are still advised to isolate not only from people but also from animals. A number of methods for specific prevention, diagnosis, and immunization against a wide range of coronavirus infections are being developed at the All-Russia Research Institute for Animal Protection.

20.
Radiats Biol Radioecol ; 51(6): 651-9, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-22384714

RESUMEN

Low doses of ionizing radiation induce the adaptive effect (AE) development in human cells which is followed by a number of cell responses. These responses can be transmitted from irradiated cells to non-irradiated ones (bystander effect, BE). The major role in radiation-induced BE is played by an oxidative stress (OS) and a DNA-signaling pathway, in which extracellular DNA fragments (ecDNA) are the factors of stress-signalization. We propose the following sequence of events in this signaling system: irradiation-OS-DNA modification-apoptosis of irradiated cells-ecDNA-signal acceptance by non-irradiated cells-OS-DNA modification, etc. We observed a radiation-induced BE which is accompanied by DNA-signaling pathway in differentiated and undifferentiated human cells forming monolayer or suspension cultures. Here we discuss several aspects of the radiation-induced BE mechanism and its persistence possibilities.


Asunto(s)
Adaptación Fisiológica , Efecto Espectador/fisiología , Daño del ADN , ADN/metabolismo , ADN/efectos de la radiación , Radiación Ionizante , Apoptosis/efectos de la radiación , Diferenciación Celular/efectos de la radiación , Células Cultivadas , ADN/química , Relación Dosis-Respuesta en la Radiación , Humanos , Estrés Oxidativo , Transducción de Señal
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