54 research outputs found
Comparative study of melaphen and kinetin influence on the growth and energetic process of plant cells
The results obtained for the unicellular algae Chlorella vulgaris as an object indicate that synthetic preparation melaphen, like kinetin, participates in regulation of many physiological processes in plants. It is concluded from the data on unidirectional action of natural phytohormone kinetin and melaphen on the plant cell. However, their action mechanism can be not identical
CHANGE OF NON-SPECIFIC FACTORS OF IMMUNITY UNDER INFLUENCE OF INTERFERON INDUCTOR (CYCLOFERON) IN BRONCHIAL ASTHMA IN CHILDREN
The aim of the work was to evaluate the effect of immunomodulation therapy on factors of nonspecific immunity in children with bronchial asthma (BA) by including interferon (cycloferon) in a standard therapy. 120 children with BA aged from 5 to 14 were examined. The main group (n = 60) included children who, in addition to basic therapy, received an interferon inducer (cycloferon) according to the generally accepted scheme. In comparison group were children who received only basic therapy (n = 60), depending on the severity of the disease. In control group were 25 healthy children. The level of serum interferon, virus-induced interferon production (VII), mitogen-stimulated production of interferon (MSI), phagocytic activity of neutrophils, as well as spontaneous and induced activity were determined. The arithmetic mean (M) and the absolute value error (m) were statistically calculated. The reliability of the differences was determined by the t-test of the Student (p < 0,05). The analysis of the indices of interferon status and phagocytic activity, depending on the type of therapeutic tactics, showed that as a result of the inclusion of cycloferon in the baseline, there was a significant increase in the levels of VII (p < 0,05) and MSI (p < 0,05 ), spontaneous and induced neutrophil activity. It was noted that this positive effect was more noticeable in moderate and severe BA (p < 0,05). Activation of factors of nonspecific protection contributed to a decrease in the frequency of exacerbations of BA in children, as well as a longer-term clinical remission in this contingent of children
Experimental opisthorchiasis: a study of blood cells, hematopoiesis and startle reflex in laboratory animals
One of the species of the family Opisthorchiidae, Opisthorchis felineus (O. felineus), causes severe disturbances in humans and animals, and so it is the subject of important research studies. Two weeks after infection we compared the impact of O. felineus invasion on the changes in blood cells composition, bone marrow hematopoiesis and behavioral startlereflex in inbred C57BL/6 male mice and Syrian hamsters (Mesocricetus auratus). Considerable interspecies differences were revealed for many parameters estimated. It was found that the relative weight of the main organ of the peripheral immune system – spleen, is significantly larger in mice than in hamsters. Moreover, the infection with O. felineus caused a significant enlargement of the spleen only in mice. More pronounced changes in the blood cells composition, which was accompanied by activation of hematopoietic stem cells of myeloid and erythroid set, were determined in hamsters. Blood changes in the response to infection in mice were less severe and were not accompanied by the changes in colony formation. Mouse acoustic startle reaction differed from hamster one too. The expression of the startle reaction and the value of pre-pulse inhibition were discriminated in animals of two species. Infected hamsters had no reaction of habituation to the sound stimulus. In addition, the maturation of O. felineus worms was faster in hamsters than in mice. Data obtained suggest a greater resistance of mice to O. felineus infection, but do not exclude the availability of mice as a model in the study of processes taking place in the host during the development of experimental opisthorchiasis
AN EXPERIMENTAL STUDY OF THE EFFECT OF RARE POLYMORPHISMS OF HUMAN HBB, HBD AND F9 PROMOTER TATA BOXES ON THE KINETICS OF INTERACTION WITH THE TATA-BINDING PROTEIN
Human genes HBB, HBD and F9 belong to the hematopoiesis system. The deficiency or excess of these genes’ products is the cause of hereditary thalassemias of various severity and haemophilia B Leyden. Previously, it was shown that a number of annotated single-nucleotide polymorphisms of TATA boxes of these genes associated with the occurrence of ß- and δ-thalassemia affect the interaction with the TATAbinding protein, the interaction changing proportionally with the change in the number of gene products. In the present work, we investigate the effect of rare not annotated single-nucleotide polymorphisms (SNPs) of TATA boxes of these genes with an unknown manifestation on the TATA-binding protein interaction. To study the kinetic characteristics of TBP/TATA complex formation in vitro, doublestranded oligodeoxynucleotides identical to the TATA-containing portions of the promoters of the HBB, HBD and F9 genes (“normal” and minor alleles) and recombinant human TBP were used. It was shown that the TATA-box SNP of –25A > C (rs281864525) and the deletion of the –25AA (rs63750953) TATA-box of the β-globin gene have the same effect on the TBP/TATA affinity, which decreases 3-folds in both cases. However, the effect of these substitutions on the rate of the TBP/TATA complex formation is significantly different: SNP –25A > C decreases the rate 5-fold, and the deletion decreases the rate more than 7-fold. The influence of substitutions on the strength of the TBP/TATA complexes has a different effect. If in the case of SNP –25A > C the strength of the complexes increases 1.8-fold, then in the case of the –25AA deletion, the strength of the complexes increases 2.4-fold, even though the affinity of the TATAbinding protein to the TATA box decreases. A comparison of experimental values of affinity (KD) of the TBP/T complexes of “normal” and minor alleles with the predicted has shown that data correlate well with each other. The coefficient of linear correlation r = 0.94 (α < 0.0001). A comprehensive approach to the study of rare polymorphisms may lead to the identification of the most sensitive markers of orphan diseases, which will contribute to the development of reliable and rapid methods for their diagnosis and treatment
Hopf algebras and Markov chains: Two examples and a theory
The operation of squaring (coproduct followed by product) in a combinatorial
Hopf algebra is shown to induce a Markov chain in natural bases. Chains
constructed in this way include widely studied methods of card shuffling, a
natural "rock-breaking" process, and Markov chains on simplicial complexes.
Many of these chains can be explictly diagonalized using the primitive elements
of the algebra and the combinatorics of the free Lie algebra. For card
shuffling, this gives an explicit description of the eigenvectors. For
rock-breaking, an explicit description of the quasi-stationary distribution and
sharp rates to absorption follow.Comment: 51 pages, 17 figures. (Typographical errors corrected. Further fixes
will only appear on the version on Amy Pang's website, the arXiv version will
not be updated.
Prime movers : mechanochemistry of mitotic kinesins
Mitotic spindles are self-organizing protein machines that harness teams of multiple force generators to drive chromosome segregation. Kinesins are key members of these force-generating teams. Different kinesins walk directionally along dynamic microtubules, anchor, crosslink, align and sort microtubules into polarized bundles, and influence microtubule dynamics by interacting with microtubule tips. The mechanochemical mechanisms of these kinesins are specialized to enable each type to make a specific contribution to spindle self-organization and chromosome segregation
Back on track – On the role of the microtubule for kinesin motility and cellular function
The evolution of cytoskeletal filaments (actin- and intermediate-filaments, and the microtubules) and their associated motor- and non-motor-proteins has enabled the eukaryotic cell to achieve complex organizational and structural tasks. This ability to control cellular transport processes and structures allowed for the development of such complex cellular organelles like cilia or flagella in single-cell organisms and made possible the development and differentiation of multi-cellular organisms with highly specialized, polarized cells. Also, the faithful segregation of large amounts of genetic information during cell division relies crucially on the reorganization and control of the cytoskeleton, making the cytoskeleton a key prerequisite for the development of highly complex genomes. Therefore, it is not surprising that the eukaryotic cell continuously invests considerable resources in the establishment, maintenance, modification and rearrangement of the cytoskeletal filaments and the regulation of its interaction with accessory proteins. Here we review the literature on the interaction between microtubules and motor-proteins of the kinesin-family. Our particular interest is the role of the microtubule in the regulation of kinesin motility and cellular function. After an introduction of the kinesin–microtubule interaction we focus on two interrelated aspects: (1) the active allosteric participation of the microtubule during the interaction with kinesins in general and (2) the possible regulatory role of post-translational modifications of the microtubule in the kinesin–microtubule interaction.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42588/1/10974_2005_Article_9052.pd
Роль генов серотонинергической медиаторной системы в формировании регуляторно-адаптивных возможностей человека
Целью исследования явилось установление роли полиморфизма генов, регулирующих метаболизм серотонина, в формировании регуляторно-адаптивных возможностей человека. Материалы и методы. У 89 студентов Кубанского государственного медицинского университета (II курс) в конце учебного года оценивали уровень адаптации по индексу регуляторно-адаптивного статуса в пробе сердечно-дыхательного синхронизма (В.М. Покровский), проводимой с помощью прибора «ВНС-Микро» (ООО «Нейрософт», Россия). Также осуществляли молекулярно-генетический анализ (посредством выделения ДНК из периферической крови с помощью стандартной методики фенольно-хлороформной экстракции) для выявления полиморфизмов генов, принимающих участие в биосинтезе серотонина (генов триптофангидроксилазы – ТРН1 и ТРН2), и генов, кодирующих серотониновые рецепторы (HTR2C и HTR2A). Результаты. Все испытуемые были разделены на три группы: с «хорошими» (52,8 % студентов), «удовлетворительными» (34,8 %) и «низкими» (12,4 %) регуляторно-адаптивными возможностями. Установлено, что в группе с «хорошими» регуляторно-адаптивными возможностями наиболее распространены следующие аллели и генотипы: для гена ТРН1 − аллель *С, для гена ТРН2 − аллель *G и генотип *G/*T, для гена HTR2С − аллель *G и генотип *G/*G, для гена HTR2A − генотип *А/*G. Отмечены статистически значимые различия в частоте встречаемости гетерозиготного генотипа *А/*G по маркеру G1438A гена HTR2А между группами с «хорошими» и «удовлетворительными», а также с «хорошими» и «низкими» регуляторно-адаптивными возможностями. В обоих случаях у лиц с «хорошими» регуляторно-адаптивными возможностями преобладал гетерозиготный генотип *А/*G, тогда как гомозиготный генотип *G/*G встречался только в группе с «низкими» возможностями. Следовательно, у студентов-медиков, имеющих «хорошие» регуляторно-адаптивные возможности, были аллели и генотипы, обеспечивающие высокую чувствительность серотониновых рецепторов и достаточную активность ферментов его биосинтеза. Полученные данные показали существование зависимости регуляторно-адаптивных возможностей человека от полиморфизмов генов, участвующих как в биосинтезе серотонина, так и в его рецепции
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