66 research outputs found
Some Features of the Distribution of Aquatic Vascular Plants in Asian Russia
Some features of the distribution of aquatic vascular plants in Asian Russia (limits of distribution and phytogeographical patterns) are discussed. Many northern species penetrate far to the south via watersheds and mountain systems, while southern species go far to the north by the valleys of large rivers. Some species considered circumpolar are represented by 2–3 allopatric species. For some species, the ranges have been expanded in Asian Russia, some other taxa have been combined in one widespread species. The possible centers of the diversity of this group are outlined (Southern Siberia, Amur and Primorie areas, Central Yakutia and Kamchatka).
Keywords: aquatic vascular plants, distribution, limits, patterns, Asian Russi
THE MOLECULAR GENETIC STUDY OF KRIM-SAGHYZ (Taraxacum hybernum Steven) USING SSR, RAPD AND ISSR MARKERS
Krim-saghyz (Taraxacum hybernum Steven) is an alternative to Hevea brasiliensis as a source of natural rubber. In Russia, krim-saghyz is common only in the Crimean Peninsula and is traditionally named after it. In spite of its potential for economical use, the genetic structure of the Crimean population of this plant is still unexplored. In this regard, the purpose of our work was a comparative molecular-genetic characterization of T. hybernum from various habitats of the Crimean Peninsula using SSR, RAPD and ISSR markers. According to the plan, we collected achenes, leaves and roots of krim-saghyz in 10 spots all over the Crimean Peninsula. We found the plants in the western part of the southern Crimean coast and the western part of the Crimean foothills, which are two general regions of the area of this species. Total DNA was extracted from dry leaves of krim-saghyz with cetyltrimethylammonium bromide (CTAB). For the first time 12 SSR, 3 RAPD and 3 ISSR markers were tested on krim-saghyz. To observe polymorphism of RAPD- and ISSR-fragments, we used analytical electrophoresis in 1.7 % agarose gel. To compare the length of SSR amplicons, we used gel-electrophoresis in 8 % polyacrylamide gel. We found that the Crimean population of krim-saghyz appears to be genetically homogeneous. This could be due to a small geographic range and apomictic reproduction of this species. However, the phenotypical diversity within the population of T. hybernum is well known from the literature. Consequently, the study of the DNA polymorphism of this species should be continued, in particular, with the help of high-resolution techniques
Иммуногистохимический анализ аберрантной экспрессии виментина в карциноидных опухолях легкого
Objective: to the study of the vimentin aberrant expression in the carcinoid tumors of lung, which is a rare group of epithelial neuroendocrine neoplasms with common morphological characteristics and highly variable clinical course.Materials and methods. Vimentin expression was studied using immunohistochemical analysis in neoplasms of 34 patients with lung carcinoid tumors, which included 17 cases in the categories of typical and atypical carcinoids.Results. Overall positive cytoplasmic immunoreactivity was observed in 9 (26.5 %) of the 34 studied tumors. Staining for vimentin was positive in 2 (11.8 %) of typical carcinoid and in 7 (41.2 %) of atypical carcinoid specimens. Expression of vimentin was more often observed in the atypical carcinoids category and was significantly associated with increased grade (p = 0.05), and cell proliferation taking into account the Ki-67 index (p = 0.008).Conclusion. These results suggest that expression of vimentin as an epithelial-mesenchymal transition-related marker plays an important role in the progression of carcinoid tumors. It may prove useful for diagnostic purposes, and also be used as a potential criterion for prognosis assessment of this type of tumors.Цель исследования – изучение аберрантной экспрессии виментина в карциноидных опухолях легкого, которые образуют группу редких эпителиальных нейроэндокринных новообразований с общими морфологическими характеристиками и крайне вариабельным клиническим течением.Материалы и методы. Особенности экспрессии виментина были изучены с помощью иммуногистохимического анализа в новообразованиях 34 больных c карциноидными опухолями легкого, которые включали по 17 случаев в категориях типичных и атипичных карциноидов.Результаты. Положительная цитоплазматическая иммунореактивность выявлена в общей группе в 9 (26,5 %) из 34 изученных опухолей. Окрашивание антителами к виментину было положительным в 2 (11,8 %) типичных и в 7 (41,2 %) атипичных карциноидах. Показано, что частота выявления виментина выше в категории атипичных карциноидов и статиститически значимо связана с увеличением степени злокачественности (р ≤0,05) и повышением пролиферативной активности клеток с учетом индекса Ki-67 (р = 0,008).Заключение. Полученные результаты демонстрируют, что экспрессия виментина как маркера эпителиально-мезенхимального перехода играет важную роль в прогрессии карциноидных опухолей. Она может быть использована в диагностических целях, а также служить потенциальным параметром оценки прогноза опухолей данного типа
Изменение уровня маркеров воспаления и состояние периферического кровотока в микроциркуляторном русле кожи у больных хронической обструктивной болезнью легких
Levels of inflammatory markers and skin microcirculation were studied in patients with chronic obstructive pulmonary disease. Proinflammatory cytokine concentrations and number of desquamated endothelial cells in blood flow were significant increased during exacerbation compared with controls. The increase in proinflammatory cytokine concentrations in exacerbation was accompanied by increased skin perfusion, increased oscil lation amplitudes in the frequency ranges of respiratory rhythm and higher endothelial activity compared with controls. In stable condition, the lev els of proinflammatory cytokines decreased compared with those in exacerbation. Myogenic activity was decreased twice in patients with stable con dition compared with healthy persons. The endothelialdependent vasodilation did not change and the endothelialindependent vasodilation increased in all patients compared with controls.Исследованы уровни маркеров воспаления и состояние периферической микрогемодинамики кожи у пациентов с хронической обструктивной болезнью легких. В стадии обострения выявлено существенное повышение концентраций провоспалительных цитокинов и числа десквамированных эндотелиоцитов в крови относительно контрольной группы. Повышение концентрации провоспалительных цитокинов у таких больных сопровождалось увеличением перфузии кожи кровью, увеличением амплитуд колебаний в диапазонах респираторного ритма и эндотелиальной активности по сравнению с контрольной группой. У пациентов в стадии ремиссии наблюдалось достоверное снижение уровня исследуемых веществ относительно больных в стадии обострения. В этой группе пациентов выявлено снижение миогенной активности микроциркуляторного русла в 2 раза относительно группы контроля. По сравнению с контрольной группой, у всех больных обнаружено отсутствие изменений и усиление эндотелийнезависимой вазодилатации микрососудов
ЭКОЛОГИЧЕСКАЯ РОЛЬ ЛЕСОВ В СИБИРИ
The article explores environmental situation in concern of the forests in Siberia and their role as they are very important in the economic aspect. The forests influence the natural processes in the country and bordering countries; they produce bioenergy and oxygen as well. The role of the forests is to influence ionic air regime, purify the air from hazardous gases and dust, reduce noise pollution level etc. The authors found out 1 m3 of the air in Siberian industrial cities contain from 100 to 500 thousands of dust and soot particles whereas the forests contain dust and soot particles 1000 times less. One hectare of forest can keep 32–68 tons of dust a year; developed wooden protective stands (40–45 m width) reduce noise pollution level from the transport on 17–23 dB. Volatile production of the forest appeared to be the important factor of their health-related features. The forests in extremely continental climate of Siberia influence such abiotic environmental factors as wind regime, solar radiation, air and soil temperature regime, precipitation, humidity etc. The publication shows that average yearly wind speed is up to 8 m/sec in bare Siberian tundra, 5 m/sec in sparsely wooded steppe (8 forest cover percent), 4 m/sec in the forest-steppe (18 forest cover percent) and 2.5–3 m/sec in taiga zone (40–50 forest cover percent). Abatement of wind speed influences better climate and V. V. The authors outline that beam solar radiation in the pinetum is 45 %, 30 % in the hardwood and 25 % in spruce forest. Increasing of forest cover percent from 30 to 70 affects low air temperature during vegetation period on 5…13 ºС in regards the average temperature of surrounding area. Soil temperature at a depth of 0.4 meter in December in the forest-steppe area of Western Siberia is –4,7 ºС, and in the southern taiga –1,2 ºС; soil temperature in June in the forest-steppe is +15,6 ºС, and +10 ºС in the southern taiga. Snow cover of leafed forests contains 15–30 % water more and softwood contains 5–10 % water more than in the open biota. Forests influence greatly hydrological regime of rivers. The total square of water-conservation forest in Siberia is 19.6 mln ha. Forests are greatly concerned with wind erosion control and dust whirls damaging the crops. Wind erosion areas in Western Siberia are spread in the steppe zone, mostly in Kulundinskaia steppe covering 17 mln ha. The article declares that crops and sowings margined with permeable shelterbelt produce crop yield 15–20 % higher than that in treeless areas.Приведено экологическое состояние и роль лесных ресурсов в Сибири, которые имеют важное народно-хозяйственное значение. Они оказывают смягчающее воздействие на природные процессы на территории страны и смежных государств, являются аккумулятором и носителем биоэнергии и фабрикой кислорода. Роль лесов заключается также в способности положительно влиять на ионный режим воздуха, очищать его от вредных газов и пыли, снижать уровень шума и др. В 1 м3 воздуха сибирских индустриальных центров содержится от 100 до 500 тыс. частиц пыли и сажи, в лесу их почти в 1000 раз меньше. Гектар леса в состоянии задержать от 32 до 68 т пыли в год. Хорошо развитые древесные защитные насаждения шириной до 40–45 м снижают уровень шума от городского транспорта на 17–23 дБ. Важным фактором, обусловливающим лечебно-оздоровительные функции лесов, является их фитонцидность. В условиях резко-континентального климата Сибири лес активно влияет на такие абиотические факторы окружающей среды, как ветровой режим, солнечная радиация, температурный режим воздуха и почв, атмосферные осадки, влажность воздуха и др. Так, в безлесной сибирской тундре средняя годовая скорость ветра достигает 8 м/с, в малолесной степи (лесистость 8%) – 5, в лесостепной зоне (лесистость 18%) – 4, в лесной таежной зоне (лесистость 40–50%) – 2,5–3 м/с. Уменьшение силы ветра влияет на улучшение климата, и наоборот. Установлено, что по сравнению с открытой местностью прямая и рассеянная солнечная радиация в сосновом насаждении составляет 45%, в лиственном – 30, в еловом – 25. Увеличение лесистости с 30 до 70% обусловливает снижение температуры воздуха в течение вегетационного периода на 5–13ºС в сравнении со средней температурой окружающей местности. В лесостепной зоне Западной Сибири в декабре почва на глуби- не 0,4 м имеет температуру в среднем –4,7ºС, а в южной тайге –1,2ºС, в июне обратная картина; в лесостепи температура почвы +15,6ºС, в южной тайге +10 ºС. В лиственных лесах в снежном покрове накапливается воды на 15–30, а в хвойных – на 5–10% больше, чем на открытых биотопах. Леса оказывают мощное влияние на гидрологический режим рек. Общая площадь выделенных водоохранных лесов в Сибири составляет 19,6 млн га. Особенно велика роль лесов и лесных полос в борьбе с ветровой эрозией, с губительными для урожаев пыльными бурями. Районы действия ветровой эрозии в Западной Сибири распространены в степной зоне, преимущественно в Кулундинской степи, занимающей 17 млн га. Посевы зерновых и других сельскохозяйственных культур, окаймленные продуваемыми лесополосами, дают урожайность на 15–20% выше, чем посевы, размещенные на безлесных площадях
Genomic insights into an obligate epibiotic bacterial predator: Micavibrio aeruginosavorus ARL-13
Bacterial Surface Appendages Strongly Impact Nanomechanical and Electrokinetic Properties of Escherichia coli Cells Subjected to Osmotic Stress
The physicochemical properties and dynamics of bacterial envelope, play a major role in bacterial activity. In this study, the morphological, nanomechanical and electrohydrodynamic properties of Escherichia coli K-12 mutant cells were thoroughly investigated as a function of bulk medium ionic strength using atomic force microscopy (AFM) and electrokinetics (electrophoresis). Bacteria were differing according to genetic alterations controlling the production of different surface appendages (short and rigid Ag43 adhesins, longer and more flexible type 1 fimbriae and F pilus). From the analysis of the spatially resolved force curves, it is shown that cells elasticity and turgor pressure are not only depending on bulk salt concentration but also on the presence/absence and nature of surface appendage. In 1 mM KNO3, cells without appendages or cells surrounded by Ag43 exhibit large Young moduli and turgor pressures (∼700–900 kPa and ∼100–300 kPa respectively). Under similar ionic strength condition, a dramatic ∼50% to ∼70% decrease of these nanomechanical parameters was evidenced for cells with appendages. Qualitatively, such dependence of nanomechanical behavior on surface organization remains when increasing medium salt content to 100 mM, even though, quantitatively, differences are marked to a much smaller extent. Additionally, for a given surface appendage, the magnitude of the nanomechanical parameters decreases significantly when increasing bulk salt concentration. This effect is ascribed to a bacterial exoosmotic water loss resulting in a combined contraction of bacterial cytoplasm together with an electrostatically-driven shrinkage of the surface appendages. The former process is demonstrated upon AFM analysis, while the latter, inaccessible upon AFM imaging, is inferred from electrophoretic data interpreted according to advanced soft particle electrokinetic theory. Altogether, AFM and electrokinetic results clearly demonstrate the intimate relationship between structure/flexibility and charge of bacterial envelope and propensity of bacterium and surface appendages to contract under hypertonic conditions
Immunohistochemical evaluation of vimentin aberrant expression in lung carcinoid tumors
Objective: to the study of the vimentin aberrant expression in the carcinoid tumors of lung, which is a rare group of epithelial neuroendocrine neoplasms with common morphological characteristics and highly variable clinical course.Materials and methods. Vimentin expression was studied using immunohistochemical analysis in neoplasms of 34 patients with lung carcinoid tumors, which included 17 cases in the categories of typical and atypical carcinoids.Results. Overall positive cytoplasmic immunoreactivity was observed in 9 (26.5 %) of the 34 studied tumors. Staining for vimentin was positive in 2 (11.8 %) of typical carcinoid and in 7 (41.2 %) of atypical carcinoid specimens. Expression of vimentin was more often observed in the atypical carcinoids category and was significantly associated with increased grade (p = 0.05), and cell proliferation taking into account the Ki-67 index (p = 0.008).Conclusion. These results suggest that expression of vimentin as an epithelial-mesenchymal transition-related marker plays an important role in the progression of carcinoid tumors. It may prove useful for diagnostic purposes, and also be used as a potential criterion for prognosis assessment of this type of tumors
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