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1.
Dokl Biol Sci ; 505(1): 109-112, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36038797

RESUMO

Stress exposures during vegetation are known to reduce the yield in crops, but the intensity and duration of stress is rather difficult to determine from the crop loss. Allelotoxins are released from plants into soil on exposure to stress factors. Soil allelotoxicity after vegetation was assumed to provide a diagnostic parameter that characterizes the total stress effect on crops. To verify the assumption, changes in soil allelotoxicity were studied after vegetation of three winter wheat cultivars fed with different amounts of nitrogen fertilizers. The cultivars Nemchinovskaya 85, Moskovskaya 39, and Lutescens 982/08 were found to differently respond to fertilizing. Nemchinovskaya 85 and Lutescens 982/08 showed lower stress responses at higher doses of nitrogen fertilizers, while their responses were appreciable when soil nitrogen was lacking. In the case of Moskovskaya 39, higher doses of nitrogen fertilizers caused an adverse reaction of increased allelotoxin release. Stepwise nitrogen fertilization was concluded to be necessary for preventing delayed plant development in the case of this cultivar. The results confirmed that soil allelotoxicity measured growing plants can serve as an indicator of stress caused by the growth conditions and use of various agricultural techniques.


Assuntos
Fertilizantes , Solo , Agricultura/métodos , Produtos Agrícolas , Fertilizantes/análise , Fertilizantes/toxicidade , Nitrogênio/análise
2.
Dokl Biol Sci ; 504(1): 78-81, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35821299

RESUMO

As is well known from the mid-20th century, films of organomineral gels cover and bind soil particles in soils. Soil contact with water has been shown to lead to water absorption by gels and gel swelling. The change of gel properties in soils should manifest itself in a change in the viscosity of soil pastes. A vibrating viscometer was proposed to use to determine the viscosity of soil pastes. The physical meaning laid down in Einstein's formula was used to interpret the results. This made it possible to assess the degree of gel swelling by the amount of water that remained capable of moving independently of soil particles, that is, was not included in soil gels (free water). The effect on the degree of swelling of soil gels was studied for (1) the moisture content in soil samples used to prepare soil pastes, (2) the time after adding water during the preparation of soil samples used subsequently to obtain soil pastes, and (3) the sample preparation of soil samples (initial, autoclaved, or dried to air-dry and absolutely dry states and re-moistened) used to obtain soil pastes. Experiments showed that (1) the degree of swelling of soil gels increased with the increasing moisture content in soil samples, (2) a longer time of interaction of soil samples with water led to a greater degree of swelling of soil gels, and (3) different degrees of swelling of soil gels were observed in pastes prepared from soil samples that had the same moisture content, but differed in sample preparation protocol.


Assuntos
Solo , Água , Géis
3.
Dokl Biol Sci ; 507(1): 272-276, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36781524

RESUMO

It is well-known that soil allelotoxicity and the water stability of soil structure are determined by the entry of plant residues into the soil, but the relationship of these soil properties has not been investigated. Soil samples from the fields of the Federal Research Center "Nemchinovka" after growing 25 cultivars of spring and winter wheat on plots with sod-podzolic soil are selected in this study. The effect of the soil's allelotoxicity of plot samples on the germination of spring wheat seed of the Liza cultivar is studied by the biotesting method. The water stability of the soil structure is determined for the same samples. The existence of a sigmoid dependence between the allelotoxicity of soil samples and their water stability with a correlation greater than 95% is established. The presence of this dependence is apparently related to the increase in the soil's water stability with an increase in the amount of fresh plant residues entering them, which is known from the literature, and the transition of the allelotoxins' effects from stimulation to suppression with a growth in their concentration in soils.


Assuntos
Solo , Água , Solo/química , Triticum , Sementes , Estações do Ano
4.
Dokl Biochem Biophys ; 499(1): 238-241, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34426919

RESUMO

The influence of various types of impacts on soil samples on the germination of seeds and the development of seedlings in comparison with sand (allelotoxicity) was studied. It is established that various types of soil sample preparation can significantly affect their allelotoxicity. It is shown that initial soil stimulated seedling development (+23%). Drying to air-dry state with further wetting increased the allelotoxicity to -27%. Autoclaving of samples (148°C, 4.5 atm) increased their allelotoxicity to -77%. The data obtained suggest that allelotoxins can exist in the soil in active and fixed forms and pass from the fixed form to the active form under various types of impacts on the soil. The study of the influence of the allelotoxicity of soil samples on the application efficiency of sorption-stimulating preparation (SSP), used for the pre-sowing treatment of spring wheat seeds, shows that the application effect of SSP monotonically decreases when allelotoxicity increases. The calculations show that the amount of sorbent used to protect seeds from allelotoxins is 3-4 orders of magnitude lower than the amount that can fix allelotoxins contained in soils. It follows from above that the development of seed seedlings is affected only by a small part of allelotoxins present in soils in the active state.


Assuntos
Germinação , Sementes/crescimento & desenvolvimento , Estações do Ano , Solo/química , Triticum/crescimento & desenvolvimento
5.
Ter Arkh ; 90(6): 130-136, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30701916

RESUMO

Goodpasture's disease (anti-GBM disease) is a rare small vessels vasculitis characterized by the presence of autoantibodies directed against the glomerular basement membrane (GBM) and alveolar basement membrane. Common feature of anti-GBM disease is a combination of rapidly progressive glomerulonephritis and alveolar hemorrhage (pulmonary-renal syndrome). We present a case of atypical disease course in a young male patient who developed alveolar hemorrhage without renal failure. The only symptom of renal involvement was isolated hematuria. Plasmapheresis combined with immunosuppression (cyclophosphamide and corticosteroids) was effective. We present a review of state-of-art data on the pathogenesis and disease course of anti-GBM disease.


Assuntos
Doença Antimembrana Basal Glomerular , Glomerulonefrite , Doença Antimembrana Basal Glomerular/complicações , Doença Antimembrana Basal Glomerular/diagnóstico , Autoanticorpos , Ciclofosfamida , Hematúria/etiologia , Hemorragia/etiologia , Humanos , Masculino
6.
Georgian Med News ; (262): 71-76, 2017 Jan.
Artigo em Russo | MEDLINE | ID: mdl-28252432

RESUMO

Spouse deadaptation is polietiologic health problem that leads to medical, psychological and social consequences that causing the need to find the key factors of its development. The research of the influence of migraine, occurring in one in five women, on the formation of deadaptation of the married couple was conducted. The author analyzes the decline of daily activity, quality of life and development of the personal characteristics of women depending on the clinical course of the disease. The interrelation was established between different variants of personality disorders in patients with migraine and types of sexual dysfunction. The most common form of sexual dysadaptation in all types of personality disorders revealed communicative. The role of men in causing interpersonal conflict in terms of disharmony of sexual relations between spouses was described. The research reveals the main factors affecting the degree of spouse deadaptation that will form the basis of psychocorrective program.


Assuntos
Adaptação Psicológica , Casamento/psicologia , Transtornos de Enxaqueca/psicologia , Cônjuges/psicologia , Adulto , Conflito Psicológico , Feminino , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/fisiopatologia , Transtornos Neuróticos/psicologia , Estudos Prospectivos , Índice de Gravidade de Doença , Comportamento Sexual , Disfunções Sexuais Psicogênicas/psicologia , Comportamento Social , Adulto Jovem
8.
J Neuroendocrinol ; 25(11): 1231-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23927034

RESUMO

Single-molecule detection enables us to visualise the real-time dynamics of individual molecules in live cells. We review the recent advancements in single-molecule fluorescence tracking of receptor protein mobility in the neuronal membrane. First, we discuss the practical consideration of single-molecule tracking in neurones, including the choice of cells and possible fluorescent labelling, as well as the appropriate optical set-up and imaging technology. We then describe the analysis of the single-molecule imaging data, including its theoretical and practical aspects of and relevant estimations of the biophysical parameters. Finally, we provide an example of a single-molecule tracking study in neuroendocrinology and highlight the next frontiers of single-molecule detection technologies.


Assuntos
Membrana Celular/ultraestrutura , Proteínas de Membrana/ultraestrutura , Imagem Molecular/métodos , Neurônios/ultraestrutura , Animais , Imagem Molecular/instrumentação
9.
Med Tekh ; (1): 4-9, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17419338

RESUMO

The basic features of the process of development of medical optical introscopes are considered. Design characteristics of preproduction and production models of devices for diagnosis of the brain and the mammary gland are described.


Assuntos
Engenharia Biomédica , Encefalopatias/diagnóstico por imagem , Doenças Mamárias/diagnóstico por imagem , Lasers , Óptica e Fotônica/instrumentação , Humanos , Radiografia
10.
Cereb Cortex ; 15(10): 1497-509, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15659656

RESUMO

Neurons of similar frequency preference are arranged in isofrequency bands (IFBs) across the primary auditory cortex (AI) of many mammals. Across the AI of the cat, one of the most frequently studied species for auditory anatomy and function, we demonstrate IFB-like responses using optical imaging of intrinsic signals (OIS). Optically defined activations were extensively elongated along the dorsoventral axis of AI (the ratio of the major and minor axes was approximately 2:1), and systematically shifted as a function of stimulus frequency. The elongation of this IFB-like zone was more conspicuous at higher frequencies. In the ventral sector of the imaged field, the IFB-like zones of activation evoked at different pure tone frequencies tended to overlap extensively. Electrophysiological recording from loci within the optically defined zones of activation revealed matched responses to the frequencies used for optical imaging at 65% of these loci. The dorsoventral orientation of these zones of activation was also closely matched with the orientation of tangentially spreading intrinsic axon terminals, as revealed anatomically. The visualization of IFB-like architecture and tonotopic organization by OIS provides a basic framework for investigating the relationships of different spectral channels and between multiple acoustic parameters at a neuronal population level.


Assuntos
Córtex Auditivo/fisiologia , Transdução de Sinais/fisiologia , Estimulação Acústica , Animais , Mapeamento Encefálico , Gatos , Interpretação Estatística de Dados , Eletrofisiologia , Feminino , Processamento de Imagem Assistida por Computador , Cinética , Masculino , Vias Neurais/fisiologia , Pressão , Terminações Pré-Sinápticas/fisiologia
11.
Med Tekh ; (3): 6-8, 2004.
Artigo em Russo | MEDLINE | ID: mdl-15293494

RESUMO

Described in the paper is a reconstruction algorithm for special distributions of optical parameters of biological objects based on the non-stationary axial model of radiation transport in case of proportionality of the absorption and scattering coefficients. The proportionality coefficient, used in reconstruction, is shown to influence a precision of images being restored. The appropriate recommendations are defined of how to diminish the occurring distortions.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Tomografia Óptica/métodos , Espalhamento de Radiação
12.
Med Tekh ; (3): 3-7, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12224249

RESUMO

The effects of light refraction and reflection on the quality of image reconstruction in medical transmission optical tomography of high-scattering media are considered. It has been first noted that light refraction not only distorts the geometric scheme of measurements, but may lead to the appearance of object areas that cannot be scanned. Some ways of decreasing the effect of refraction on the reconstruction of spatial distribution of the extinction coefficient are stated.


Assuntos
Luz , Refração Ocular , Tomografia por Raios X , Fenômenos Biofísicos , Biofísica , Estudos de Viabilidade , Humanos , Processamento de Imagem Assistida por Computador , Lasers , Matemática , Modelos Biológicos , Modelos Teóricos , Óptica e Fotônica , Espalhamento de Radiação
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