115 research outputs found
Aggregatibacter actinomycetemcomitans leukotoxin induces cytosol acidification in LFA-1 expressing immune cells
Studies have suggested that Aggregatibacter actinomycetemcomitans leukotoxin (LtxA) kills human lymphocyte function-associated antigen 1 (LFA-1; CD11a/CD18)-bearing immune cells through a lysosomal-mediated mechanism. Lysosomes are membrane-bound cellular organelles that contain an array of acid hydrolases that are capable of breaking down biomolecules. The lysosomal membrane bilayer confines the pH-sensitive enzymes within an optimal acidic (pH 4.8) environment thereby protecting the slightly basic cytosol (pH 6.8-7.5). In the current study, we have probed the effect of LtxA-induced cytolysis on lysosomal integrity in two different K562 erythroleukemia cell lines. K562-puro/LFA-1 cells were stably transfected with CD11a and CD18 cDNA to express LFA-1 on the cell surface while K562-puro, which does not express LFA-1, served as a control. Following treatment with 100 ng ml-1 LtxA cells were analyzed by live cell imaging in conjunction with time-lapse confocal microscopy and by flow cytometry. Using a pH-sensitive indicator (pHrodo®) we demonstrated that the toxin causes a decrease in the intracellular pH in K562-puro/LFA-1 cells that is noticeable within the first 15 min of treatment. This process correlated with the disappearance of lysosomes in the cytosol as determined by both acridine orange and LysoTracker® Red DND-99 staining. These changes were not observed in K562-puro cells or when heat inactivated toxin was added to K562-puro/LFA-1. Our results suggest that LtxA induces lysosomal damage, cytosol acidification, which is followed by cell death in K562-puro/LFA-1 cells. © 2016 John Wiley & Sons A/S
Third order dielectric susceptibility in a model quantum paraelectric
In the context of perovskite quantum paraelectrics, we study the effects of a
quadrupolar interaction , in addition to the standard dipolar one .
We concentrate here on the nonlinear dielectric response , as
the main response function sensitive to quadrupolar (in our case
antiquadrupolar) interactions. We employ a 3D quantum four-state lattice model
and mean-field theory. The results show that inclusion of quadrupolar coupling
of moderate strength () is clearly accompanied by a
double change of sign of from negative to positive, near the
quantum temperature where the quantum paraelectric behaviour sets in. We
fit our to recent experimental data for SrTiO, where the
sign change is identified close to .Comment: 22 page
КУЛЬТУРА БОБОВ ОВОЩНЫХ В НЕЧЕРНОЗЕМНОЙ ЗОНЕ РОССИИ
Beans (Vicia faba L.) is the one of the ancient crops which have been cultivated and used for food. The historical note about bean utilization in ancient world and in Russia, and the information aboutcenters of origin, food value of seeds are presented in this review. Botanical characteristics of three bean varieties of VNIISSOK breeding are described.Бобы (Vicia faba L.) – одно из самых древних растений, употребляемых человеком в пищу, и, соответственно, введённых в культуру. В обзоре дана историческая справка об использовании бобов в древнем мире и в России, представлены сведения о центрах происхождения и пищевой ценности семян бобов овощных. Приведено описание трёх сортов бобов овощных селекции ВНИИССОК
Изменчивость морского льда в Арктике по данным Арктического портала
The Arctic Portal of the Laboratory of Satellite Oceanography of the Russian State Hydrometeorological University is an open geo-informational system designed for operational monitoring of the sea ice–ocean–atmosphere system in the Arctic. Possibilities to use the Arctic Portal for the Arctic sea ice monitoring on the basis of satellite data, as well as the types of satellite measurements suitable for studying the properties of sea ice: active and passive microwave data; data of spectral radiometers in the infrared (IR) and visible ranges are considered. Every type of satellite data has certain limitations. For the study of sea ice the most suitable are the all-season remote sensing data – measurements of microwave instruments, independent of clouds and time of a day. Existing in the world resources of the sea ice maps and satellite data on sea ice are either closed for users or limited in their informational content. Several types of satellite data are currently available on the Arctic portal: Sentinel-1 synthetic aperture radar (SAR) images, 8-day averaged MODIS reflectivity data, optical and IR MODIS data of original time and spatial resolution, Norwegian Meteorological University sea ice maps, and data on consolidation of sea ice, based on passive microwave radiometer measurements. Some data is additionally available in the test mode. The effectiveness of combined use of various satellite data on the sea ice is proved by the examples of sea ice analyses.Представлены возможности Арктического портала (геоинформационного сервиса) для мониторинга ледяного покрова Арктики на основе спутниковых данных. Дан обзор основных типов спутниковых инструментов, позволяющих изучать морской лёд. Обоснована эффективность совместного применения результатов обработки разных спутниковых данных, имеющихся в среде геосервиса
Over-the-Counter Monocyclic Non-Steroidal Anti-Inflammatory Drugs in Environment—Sources, Risks, Biodegradation
Recently, the increased use of monocyclic
non-steroidal anti-inflammatory drugs has resulted in
their presence in the environment. This may have
potential negative effects on living organisms. The
biotransformation mechanisms of monocyclic nonsteroidal
anti-inflammatory drugs in the human body
and in other mammals occur by hydroxylation and
conjugation with glycine or glucuronic acid.
Biotransformation/biodegradation of monocyclic
non-steroidal anti-inflammatory drugs in the environment
may be caused by fungal or bacterial microorganisms.
Salicylic acid derivatives are degraded by
catechol or gentisate as intermediates which are
cleaved by dioxygenases. The key intermediate of
the paracetamol degradation pathways is hydroquinone.
Sometimes, after hydrolysis of this drug, 4-
aminophenol is formed, which is a dead-end metabolite.
Ibuprofen is metabolized by hydroxylation or
activation with CoA, resulting in the formation of
isobutylocatechol. The aim of this work is to attempt
to summarize the knowledge about environmental risk
connected with the presence of over-the-counter antiinflammatory
drugs, their sources and the biotransformation
and/or biodegradation pathways of these
drugs
NEURAL NETWORKS AS A CLASSIFICATION TOOL BIOTECHNOLOGICAL SYSTEMS (FOR EXAMPLE FLOUR PRODUCTION)
Summary. To date, artificial intelligence systems are the most common type to classify objects of different quality. The proposed modeling technology to predict the quality of flour products by using artificial neural networks allows to solve problems of analysis of the factors determining the quality of the products. Interest in artificial neural networks has grown due to the fact that they can change their behavior depending on external environment. This factor more than any other responsible for the interest that they cause. After the presentation of input signals (possibly together with the desired outputs), they self-configurable to provide the desired reaction. We developed a set of training algorithms, each with their own strengths and weaknesses. The solution to the problem of classification is one of the most important applications of neural networks, which represents a problem of attributing the sample to one of several non-intersecting sets. To solve this problem developed algorithms for synthesis of NA with the use of nonlinear activation functions, the algorithms for training the network. Training the NS involves determining the weights of layers of neurons. Training the NA occurs with the teacher, that is, the network must meet the values of both input and desired output signals, and it is according to some internal algorithm adjusts the weights of their synaptic connections. The work was built an artificial neural network, multilayer perceptron example. With the help of correlation analysis in total sample revealed that the traits are correlated at the significance level of 0.01 with grade quality bread. The classification accuracy exceeds 90%
Comparative analysis of methods for classification in predicting the quality of bread
The comparative analysis of classification methods of two-stage cluster and discriminant analysis and neural networks was performed. System of informative signs which classifies with a minimum of errors has been proposed
Thermodynamic description of generation of the second acoustic harmonics induced by an electric field in ferroelectrics
The temperature behavior of the generation of the second acoustic harmonics induced by an electric field during the transition of a crystal to the ferroelectric state has been considered based on the thermodynamic approach in the framework of the Landau model. It has been shown that the appearance of the contribution to polarization quadratic in the electric field leads to a change in the sign of the second acoustic harmonics and a change in its magnitude as compared to the paraphase. The results of the calculation are presented for the first-order and second-order transitions and in the tricritical point
BEAN CULTURE IN CHERNOZEM ZONE OF RUSSIA
Beans (Vicia faba L.) is the one of the ancient crops which have been cultivated and used for food. The historical note about bean utilization in ancient world and in Russia, and the information aboutcenters of origin, food value of seeds are presented in this review. Botanical characteristics of three bean varieties of VNIISSOK breeding are described
- …