168 research outputs found
L-NAME-induced preeclampsia: correction of functional disorders of the hemostasis system with resveratrol and nicorandil
Preeclampsia is a formidable disease of the second half of pregnancy, leading to severe complications, including disability and even death. Many authors have recognized the correlation between the severity of preeclampsia and the degree of disturbances in the hemostasis system. In this regard, the objective of this study was to assess inhibition of platelet aggregation and the possibility of its correction with resverаtrol and nicorand
The role of environmental factors for the composition of microbial communities of saline lakes in the Novosibirsk region (Russia)
Meso-substituted cationic 3- and 4-N-Pyridylporphyrins and their Zn(II) derivatives for antibacterial photodynamic therapy
Photodynamic inactivation of microorganisms known as antibacterial photodynamic therapy (APDT) is one of the most promising and innovative approaches for the destruction of pathogenic microorganisms. Among the photosensitizers (PSs), compounds based on cationic porphyrins/ metalloporphyrins are most successfully used to inactivate microorganisms. Series of meso-substituted cationic pyridylporphyrins and metalloporphyrins with various peripheral groups in the third and fourth positions of the pyrrole ring have been synthesized in Armenia. The aim of this work was to determine and test the most effective cationic porphyrins and metalloporphyrins with high photoactivity against Gram negative and Gram positive microorganisms. It was shown that the synthesized cationic pyridylporphyrins/metalloporphyrins exhibit a high degree of phototoxicity towards both types of bacteria, including the methicillin-resistant S. aureus strain. Zinc complexes of porphyrins are more phototoxic than metal-free porphyrin analogs. The effectiveness of these Zn-metalloporphyrins on bacteria is consistent with the level of singlet oxygen generation. It was found that the high antibacterial activity of the studied cationic porphyrins/metalloporphyrins depends on four factors: The presence in the porphyrin macrocycle of a positive charge (+4), a central metal atom (Zn2+) and hydrophobic peripheral functional groups as well as high values of quantum yields of singlet oxygen. The results indicate that meso-substituted cationic pyridylporphyrins/metalloporphyrins can find wider application in photoinactivation of bacteria than anionic or neutral PSs usually used in APD
Первичная цилиарная дискинезия у детей
The article presents current approaches to medical care delivery in children with primary ciliary dyskinesia. The genetic heterogeneity of the disease causes the variability of pathological symptoms in clinical practice. The most common clinical manifestation in children is the frequent inflammatory diseases of the upper and lower respiratory tract which are registered in the majority of patients, especially in young children. However, the diagnosis is often untimely due to the low disease awareness among medical specialists. The article describes the algorithm for differential diagnostic search in detail, presents approaches to the treatment and management of pediatric patients with primary ciliary dyskinesia. The material is based on clinical recommendations developed and approved by the professional association «Union of Pediatricians of Russia»; recommendations were updated in 2018.Авторами представлены актуальные подходы к оказанию медицинской помощи детям с первичной цилиарной дискинезией. Генетическая неоднородность данного заболевания обусловливает вариабельность патологических симптомов в клинической практике. Наиболее распространенное проявление болезни у детей — частые воспалительные заболевания верхних и нижних дыхательных путей, которые регистрируются у большинства пациентов, особенно у детей раннего возраста. При этом диагноз болезни зачастую устанавливается несвоевременно вследствие невысокой осведомленности специалистов о данной нозологии. В статье подробно изложен алгоритм дифференциально-диагностического поиска, представлены подходы к лечению и ведению пациентов детского возраста с первичной цилиарной дискинезией. Материал основан на клинических рекомендациях, ранее разработанных и утвержденных профессиональной ассоциацией «Союз педиатров России», актуализированных и обновленных в 2018 году
Wheat Antipodal Cells with Polytene Chromosomes in the Embryo Sac Are Key to Understanding the Formation of Grain in Cereals
The ultrastructure of antipodal cells of the Triticum aestivum embryo sac was studied at different stages of differentiation and programmed cell death. The importance of cell function in the antipodal complex is evidenced by the fact that it is fully formed before double fertilization, past the stages of proliferation of three initial cells, and several rounds of genome endoreduplication during differentiation. In this study, we showed that the actively synthesizing organelles, the granular reticulum, and Golgi apparatus, alter their structure during differentiation and death. The polymorphism of the shape of the mitochondria and plastids was demonstrated. For the first time, the actin filaments of the cytoskeleton and numerous multivesicular bodies associated with the plasma membrane were detected in the cytoplasm. The transfer of cytoplasm and organelles between antipodal cells and into the coenocyte of the endosperm was confirmed. DNA breaks and the release of cytochrome c at various stages of death were revealed. To understand the function of the antipodal cells, a quantitative PCR analysis of the expression of wheat genes involved in protective, antistress, and metabolic processes was carried out. We found that gene expression in the antipodal cell fraction was increased compared with that in the whole embryo sac. On the basis of the data, we assume that antipodal cells produce both nutrients and numerous antistress factors that ensure the normal development of the endosperm of the grain, which, in turn, further ensures the development of the embryo
Forecast of urban air pollution level by expertise
Introduction. A climate pattern with marine features is typical for St. Petersburg. Vagaries of weather and climate conditions in the last decade specify the timeliness of this work, the purpose of which is to outline the expected level of the open air pollution in St. Petersburg by the “decision tree” method. Materials and Methods. Current data of weather observations carried out at station 26063 (St. Petersburg) from 2006 to 2014 are studied and processed. Within the framework of the study, the data were considered on the vertical profile of the atmosphere obtained through radiosounding the atmosphere of St. Petersburg at 00.00 and 12.00 UTC (Universal Time Coordinated) at Voeykovo station. Research Results . In the course of the investigation, the dependence of the atmospheric air pollution level on the synoptic process and the inertial factor was established which made it possible to figure a scheme for forecasting the air pollution level in the form of the decision tree by expertise. Accuracy of the predictive determination of the expected air pollution group in St. Petersburg was calculated on the dependent material and topped 90% (nighttime hours) and 91% (daytime hours) for a cold period; and - 84% (nighttime hours) and 87% (daylight hours) for a warm period of the year. This suggests that the proposed schemes allow obtaining a more efficient prediction of the atmospheric air pollution level in a cold period of the year. Discussion and Conclusions . In conclusion, basic outcomes and inferences are summarized. - Archives of baseline standard meteorological data and data of the atmosphere radiosounding, as well as synoptic situations and information on the level of atmospheric air pollution in St. Petersburg for the period from 2006 to 2014, are formed. - Groups of synoptic processes typical for St. Petersburg from 2006 to 2014 are established. - Schemes for forecasting the atmospheric air pollution level are developed using the “decision tree” method with accuracy of 84-91%. The research results are applicable for forecasting the urban air pollution level
Trifluralin-induced disorganization of microtubular cytoskeleton alters the development of roots in Hordeum vulgare L.
The extensive use of herbicides in agriculture becomes an important factor in environmental pollution, especially in case of slowly degradable compounds. Some agents act on plants during a long period of time, even if a very low concentration of the herbicide remains in the soil. Here, we investigated the toxicological effect of a low concentration of dinitroaniline herbicide, trifluralin, on growing seedlings of
Hordeum vulgare
L. Trifluralin in concentration of 1 μg/ml inhibited root growth. The mitotic activity of meristematic cells was suppressed due to the retardation of metaphase progression — alteration that can be caused by cytoskeleton disorder. Using antibodies to α-tubulin, we investigated the distribution of microtubules in root meristem cells. During all stages of mitosis, the highly regular system of microtubular cytoskeleton observed in control cells was slightly disorganized. An examination of root structure using light and electron microscopy demonstrated that the cell walls did not form normally during cell division that led to the appearance of large multinucleated cells. Also, the premature (pathological) cell differentiation was induced by trifluralin. A part of differentiating cells showed intracellular structural changes that are consistent with programmed cell death. It seems that the development of alterations in trifluralin-treated roots was due to the microtubular cytoskeleton disorganization
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