Distribution and physiological state of microorganisms in petrochemical oily sludge

The occurrence, vertical distribution, and the physiological state of microorganisms in a petrochemical oily sludge deposit were studied. The total number and the number of viable microbial cells at depths of 0.2 and 3 m were about 10 and 108 cells/g dry wt. sludge. Most microbial cells taken from the middle (1 m deep) and the bottom (3 m deep) sludge horizons showed a delayed colony-forming ability, which suggested that the cells occurred in a hypometabolic state. The relative number of microaerobic denitrifying microorganisms steeply increased with depth. The amount of microorganisms tolerant to 3, 5, and 10% NaCl and capable of growing at 7 and 40°C varied from 102 to 108 CFU/g dry wt. sludge. Petrochemical oily sludge was found to maintain the growth of heterotrophs, among which the degraders of oily sludge and ten different individual polycyclic aromatic hydrocarbons were detected. The occurrence of highly adaptable microorganisms with an adequate metabolic potential in the petrochemical oily sludge deposit implies that its bioremediation is possible without introducing special microorganisms

Distribution and physiological state of microorganisms in petrochemical oily sludge

The occurrence, vertical distribution, and physiological state of microorganisms in a petrochemical oily sludge deposit were studied. The total number and the number of viable microbial cells at depths of 0.2 and 3 m were about 1010 and 108 cells/g dry wt sludge. Most microbial cells taken from the middle (l m deep) and the bottom (3 m deep) sludge horizons showed a delayed colony-forming ability, which suggested that the cells occurred in a hypometabolic state. The relative number of microaerobic denitrifying microorganisms steeply increased with depth. The amount of microorganisms tolerant to 3, 5, and 10% NaCl and capable of growing at 7 and 40 °C varied from 102 to 108 CFU/g dry wt sludge. Petrochemical oily sludge was found to maintain the growth of heterotrophs, among which the degraders of oily sludge and ten different individual polycyclic aromatic hydrocarbons were detected. The occurrence of highly adaptable microorganisms with an adequate metabolic potential in the petrochemical oily sludge deposit implies that its bioremediation is possible without introducing special microorganisms

The Role of Vesicles in Transporting of Cholera Toxin

The review reports on the secretion pathways of the main virulence factor of Vibrio cholerae, cholera toxin, both through the two-stage Sec-dependent type 2 secretion system and with the help of vesicles of the outer membrane of V. cholerae. The ways of toxin transfer into the host organism, depending on its form, are discussed. The well-studied free soluble cholera toxin is secreted extracellularly and transmitted in a GM1-dependent manner through cholesterolrich lipid rafts. The transfer of cholera toxin associated with vesicles has advantages over free toxin, because substances inside the outer membrane vesicles are protected from external proteases and host antibodies by the membrane that forms the vesicle. Vesicular transporting of cholera toxin into the target cell occurs via clathrin-dependent, caveolin-dependent and lipid raft-dependent endocytosis. The specific transport route is determined by the structure of the vesicles. Clathrindependent endocytosis is described for V. cholerae strains cultivated at low osmolarity of the medium, whose outer membrane vesicles contain the cholera toxin subunit A inside. Lipid raft-dependent endocytosis is characteristic of vesicles in which cholera toxin is located on the surface. In addition, endocytosis of V. cholerae outer membrane vesicles through structures known as caveolae is presented

Assessment of the Variation Range of Agglutinability in <i>Vibrio cholerae</i> Strains Isolated in the Course of Monitoring Studies

The aim of the study was to retrospectively analyze the range of variability of antigenic properties and genotypic characteristics of Vibrio cholerae R-variant strains atypical in terms of agglutinability.Materials and methods. 169 strains of V. cholerae R-variant with atypical agglutinability have been studied using the “AmpliSens® Vibrio cholerae-FL” test-system. The determination of O1 antigen was carried out using the “Ig-V. cholerae О1/О139 – ELISA/dot-ELISA” reagent kit.Results and discussion. A retrospective analysis of the complex of phenoand genotypic characteristics of strains isolated from surface water bodies in the territories of three former Soviet republics and 13 constituent entities of the Russian Federation in the course of 30-year monitoring and identified upon isolation as nontoxigenic V. cholerae R-variant strains has been performed. Upon re-identification, it was found that the strains belong to both epidemically dangerous (3.0 %) and non-dangerous strains (97.0 %). The range of variability was expressed in their distribution into three groups and consisted in retaining of agglutinability only with cholera RO serum in the first group (34.5 % of strains); the loss of this trait, but the acquisition of the ability to agglutinate in different combinations with O1, Ogawa or Inaba sera – in the second (16.7 %); and also in the loss of agglutinability with all diagnostic cholera sera – in the third (48.8 %). The presence of the wbeT gene in the compared V. cholerae classical R-variant strain does not exclude the presence of the genomic region for O1 antigen biosynthesis in other R-strains, possibly in a modified form, which can be clarified in further molecular-genetic studies. Alternatively, such strains are likely to be attributed to V. cholerae nonO1/nonO139. Strains of V. cholerae R-variant with different amounts of surface antigen (optical density range – from 0.088±0.002 to 1.226±0.003) have been identified. The data obtained can be used for monitoring of cholera in laboratories of regional and federal levels

Study of the Surface Antigenic Determinants of <i>Vibrio cholerae</i> Strains with Atypical Agglutinability Using the Panel of Monoclonal Antibodies

The aim of the work was to study surface antigenic determinants of V. cholerae R-variant strains using enzyme immunoassay and a panel of monoclonal antibodies (MAbs).Materials and methods. 60 strains of V. cholerae R-variant isolated from ambient environment objects in the territories of the former USSR and the constituent entities of the Russian Federation over a 30-year period (1988–2019) were investigated in the slide agglutination reaction with cholera diagnostic sera, enzyme immunoassay (ELISA) using the panel of MAbs specific to membrane proteins and a set of reagents “Monoclonal diagnostic immunoglobulins labeled with horseradish peroxidase, dry, for serological identification of V. cholerae O1 and O139 (in vitro) through ELISA and dot-ELISA”.Results and discussion. The analysis of the surface structures of V. cholerae R-variant strains with atypical agglutinability has been carried out applying enzyme immunoassay. It showed that individual strains with different amounts of O-antigen are registered among the studied strains identified at isolation as V. cholerae R-variant (the optical density range is from 0.261±0.002 to 1.312±0.003). Epitopes of specific O-antigen were found in some “conservative” strains (30 %) that are agglutinated only with RO serum, and in several strains (20 %) that do not have the wbeT gene that determines its synthesis, and lost agglutinability with all diagnostic cholera sera, including RO. The protein epitopes recognized by complementary MAbs are represented with varying frequency in the composition of surface antigens of R-vibrios; a decrease in their representation or absence on the cell surface correlates with the modification or loss of R-LPS and is accompanied by a negative agglutination reaction

Effects of glyprolines on free-radical oxidation in the brain neocortex of white rats in mild traumatic brain injury

The aim of the study was to compare the effect of glyproline peptides RGRGP (Arg-Gly-Arg-Gly-Pro), RGP (Arg-GlyPro), PRPGP (Pro-Arg-Pro-Gly-Pro) and PGPL (Pro-Gly-Pro-Leu) peptide substances at various concentrations on the free radical oxidation intensity of the brain tissues of Wistar males after intraperitoneal administration of peptide solutions after traumatic brain injury.Material and methods. The brain tissue of Wistar males aged 2–3 months (n = 126) were used in the experiment. RGRGP, RGP, PRPGP, and PGPL peptides were provided by Academician N.F. Myasoyedov. Traumatic brain injury (TBI) was modeled by free fall of a load. From the second to the fifth day of the experiment, the animals were injected intraperitoneally with peptides. On the sixth day, the animals were taken out of the experiment. The activity of free radical oxidation was determined in freshly prepared homogenates of sections of the cerebral cortex by chemiluminescence (CL).Results. TBI significantly enhance free-radical oxidation intensity of the neocortex in brain tissue of Wistar rats, and the studied peptides affect it in different ways - from a decrease in CL intensity (the minimum value in TBI + RGP 0.1 group) to its increase (the maximum value in TBI + RGPGP 0.1 group). The effect depends on the dose of glyproline.Conclusions. The results obtained, based on the analysis of the free radical oxidation intensity of tissues, mainly indicate a different degree of correction of tissue homeostasis indicators. It can be assumed that Arg-Pro-Gly peptide can be the basis for the development of new drugs for post-stress rehabilitation after injuries of various levels and genesis

ОКАЗАНИЕ ЭКСТРЕННОЙ НЕЙРОХИРУРГИЧЕСКОЙ ПОМОЩИ НА ТЕРРИТОРИИ ВОРОНЕЖСКОЙ ОБЛАСТИ

BACKGROUND. Сraniocerebral injury is the most common type of trauma in Russian Federation especially among working age persons. These patients require unification of surgical tactics, intensive care and continuity of treatment in order to increase of effectiveness of treatment. Purpose of the study is evaluation of emergency neurosurgical aid efficiency in Voronezh region in terms of introduction of threelevel health care system.MATERIAL AND METHODS. Neurosurgical service functioning of Voronezh Clinical Center for Disaster Medicine has been evaluated. It included treatment and transportation of patients with a brain injury during 2012–2014.CONCLUSION. Admittance of patients with severe craniocerebral injury at the hospital with neurovisualization and telecommunication equipment improves neurosurgical aid efficiency of the Center for Disaster Medicine. It is possible due to effective patient’s data transmission and shortening of time before surgical intervention. The decrease of number of groundless neurosurgical team’s rides has been registered. АКТУАЛЬНОСТЬ. Черепно­мозговая травма (ЧМТ) относится к наиболее распространенному виду травм в Российской Федерации, особенно у лиц трудоспособного возраста. Для повышения эффективности оказания медицинской помощи этим пациентам необходима унификация хирургической тактики, интенсивной терапии и преемственность лечения на различных этапах. Цель работы: проанализировать эффективность оказания экстренной нейрохирургической помощи на территории Воронежской области в условиях внедрения трехуровневой системы оказания медицинской помощи.МАТЕРИАЛ И МЕТОДЫ. Проведен анализ работы нейрохирургической службы Воронежского областного клинического центра медицины катастроф по лечению и транспортировке пациентов с нейротравмой за период с 2012 по 2014 г.ЗАКЛЮЧЕНИЕ. Госпитализация пациентов с тяжелой ЧМТ в стационар, оснащенный оборудованием для нейровизуализации и доступом к телекоммуникационной сети, повышает качество нейрохирургической помощи специалистами Центра медицины катастроф за счет оперативной передачи данных пациента и сокращения сроков начала оперативного вмешательства. При этом отмечено снижение числа необоснованных выездов нейрохирургической бригады.

Методика количественного анализа маркерного субстрата ABCB1-белка фексофенадина в лизате клеток Caco-2

One way to analyze the activity of the ABCB1 protein is to assess the accumulation of its substrate fexofenadine (F.) inside the test cells. The goal is to develop and validate a method for the quantitative analysis of F. in Caco-2 cell lysate using HPLC-MS/MS. Materials and methods. Caco-2 cell lysate was used as a matrix. The analysis was performed on an "Ultimate 3000" chromatograph with a TSQ Fortis triple quadrupole mass detector, a UCT Selectra C18 4.6 mm*100 mm 5 µm column in a gradient elution mode. The mobile phase rate was 0.3 ml/min, the sample volume was 20 µl, the ionization mode was positive, and the internal standard was amantadine (ng/ml). Sample preparation — precipitation of cell lysate protein with acetonitrile. The method was validated for the following parameters: selectivity, linearity, lower limit of quantitation (LLOQ), correctness, precision, sample transfer and sample stability. Results. Chromatograms of the blank lysate of Caco-2 cells showed no peaks with retention times characteristic of F. (5.70 min) and amantadine (3.58 min). NPKO F. was 0.5 ng/ml. F.'s transfer did not exceed 20% of NPKO, and amantadine — 5%. Based on the results of the analysis of three series of calibration standards (0.5; 1; 1.5; 5; 10; 25; 40; 50 ng/ml), linear regression equations were obtained, the correlation coefficients exceeded 0.99. Accuracy and precision were assessed within and between cycles by analyzing F. solutions in the matrix (0.5; 1.5; 25 and 40 ng/ml) within three cycles. The parameters did not exceed 20% for LLPO and 15% for other points. The stability of F. solutions (1.5 and 40 ng/ml) in the lysate was analyzed during storage at room temperature, after 3-fold freezing-thawing, storage at -80 °C for 60 days, after sample preparation and being in the autosampler for 24 hours. The accuracy was within 15% of the nominal values. Conclusions. A method for the quantitative determination of F. in Caco-2 cell lysate using HPLC-MS/MS has been developed and validated.Один из способов анализа активности ABCB1-белка — это оценка накопления его субстрата фексофенадина (Ф.) внутри тест-клеток. Цель — разработка и валидация методики количественного анализа Ф. в лизате клеток Caco-2 с помощью ВЭЖХ-МС/МС. Материалы и методы. В качестве матрицы использовался лизат клеток Caco-2. Анализ выполняли на хроматографе «Ultimate 3000» с тройным квадрупольным масс-детектором TSQ Fortis, колонкой UCT Selectra C18 4,6 мм×100 мм 5 мкм в градиентном режиме элюирования. Скорость подвижной фазы — 0,3 мл/мин, объём пробы — 20 мкл, режим ионизации — положительный, внутренний стандарт — амантадин (нг/мл). Пробоподготовка — осаждение белка лизата клеток ацетонитрилом. Методику валидировали по параметрам: селективность, линейность, нижний предел количественного определения (НПКО), правильность, прецизионность, перенос пробы и стабильность образцов. Результаты. На хроматограммах холостого лизата клеток Caco-2 не было пиков со временем удерживания, характерным для Ф. (5,70 мин) и амантадина (3,58 мин). НПКО Ф. составил 0,5 нг/мл. Перенос Ф. не превышал 20 % НПКО, а амантадина — 5 %. По результатам анализа трёх серий градуировочных стандартов (0,5; 1; 1,5; 5; 10; 25; 40; 50 нг/мл) получены уравнения линейной регрессии, коэффициенты корреляции превышали 0,99. Правильность и прецизионность оценивали внутри и между циклами, выполняя анализ растворов Ф. в матрице (0,5; 1,5; 25 и 40 нг/мл) в рамках трёх циклов. Параметры не превышали 20 % для НПКО и 15 % — для остальных точек. Стабильность растворов Ф. (1,5 и 40 нг/мл) в лизате анализировали при хранении при комнатной температуре, после 3-кратной заморозки–разморозки, хранении при -80 °С 60 сут., после пробоподготовки и нахождения в автосемплере 24 ч. Правильность находилась в пределах 15 % от номинальных значений. Выводы. Разработана и валидирована методика количественного определения Ф. в лизате клеток Caco-2 с помощью ВЭЖХ-МС/МС

Contribution of Cerebellar Sensorimotor Adaptation to Hippocampal Spatial Memory

Complementing its primary role in motor control, cerebellar learning has also a bottom-up influence on cognitive functions, where high-level representations build up from elementary sensorimotor memories. In this paper we examine the cerebellar contribution to both procedural and declarative components of spatial cognition. To do so, we model a functional interplay between the cerebellum and the hippocampal formation during goal-oriented navigation. We reinterpret and complete existing genetic behavioural observations by means of quantitative accounts that cross-link synaptic plasticity mechanisms, single cell and population coding properties, and behavioural responses. In contrast to earlier hypotheses positing only a purely procedural impact of cerebellar adaptation deficits, our results suggest a cerebellar involvement in high-level aspects of behaviour. In particular, we propose that cerebellar learning mechanisms may influence hippocampal place fields, by contributing to the path integration process. Our simulations predict differences in place-cell discharge properties between normal mice and L7-PKCI mutant mice lacking long-term depression at cerebellar parallel fibre-Purkinje cell synapses. On the behavioural level, these results suggest that, by influencing the accuracy of hippocampal spatial codes, cerebellar deficits may impact the exploration-exploitation balance during spatial navigation