Macrophage and tumor cell responses to repetitive pulsed X-ray radiation

To study a response of tumor cells and macrophages to the repetitive pulsed low-dose X-ray radiation. Methods. Tumor growth and lung metastasis of mice with an injected Lewis lung carcinoma were analysed, using C57Bl6. Monocytes were isolated from a human blood, using CD14+ magnetic beads. IL6, IL1-betta, and TNF-alpha were determined by ELISA. For macrophage phenotyping, a confocal microscopy was applied. "Sinus-150" was used for the generation of pulsed X-ray radiation (the absorbed dose was below 0.1 Gy, the pulse repetition frequency was 10 pulse/sec). The irradiation of mice by 0.1 Gy pulsed X-rays significantly inhibited the growth of primary tumor and reduced the number of metastatic colonies in the lung. Furthermore, the changes in macrophage phenotype and cytokine secretion were observed after repetitive pulsed X-ray radiation. Conclusion. Macrophages and tumor cells had a different response to a low-dose pulsed X-ray radiation. An activation of the immune system through changes of a macrophage phenotype can result in a significant antitumor effect of the low-dose repetitive pulsed X-ray radiation

Generation of electromagnetic fields of extremely high intensity by coherent summation of Cherenkov superradiance pulses

We demonstrate both theoretically and experimentally the possibility of correlating the phase of a Cherenkov superradiance (SR) pulse to the sharp edge of a current pulse, when spontaneous emission of the electron bunch edge serves as the seed for SR processes. By division of the driving voltage pulse across several parallel channels equipped with independent cathodes we can synchronize several SR sources to arrange a two-dimensional array. In the experiments carried out, coherent summation of radiation from four independent 8-mm wavelength band SR generators with peak power 600 MW results in the interference maximum of the directional diagram with an intensity that is equivalent to radiation from a single source with a power of 10 GW

Coherent summation of emission from relativistic Cherenkov sources as a way of production of extremely high-intensity microwave pulses

For relativistic Cherenkov devices, we investigate the process of high-power microwave pulse generation with its phase correlating to the sharp edge of an e-beam current pulse. Our theoretical consideration is referred to quasi-stationary and superradiative (SR) generation regimes when spontaneous emission of the e-beam edge serves as the seed for the development of further coherent oscillations. Phase correlation of the excited microwave pulses with the characteristics of the current pulse front and/or an initial external electromagnetic pulse has been additionally confirmed by particle-in-cell simulations. Pulse-to-pulse stability of the radiation phase within several percents of the oscillation period makes it possible to arrange multichannel schemes producing mutually coherent microwave pulses. In the experiments that have been carried out, the cathodes of independent generators were powered by identical accelerating pulses from strictly synchronized voltage modulators, or by splitting the pulse from a single powerful modulator. For the 2-ns regime with the power of each Ka-band backward-wave oscillator about 100 MW, we demonstrate quadratic growth of the power density in the interference maximum of the directional diagram. In a short pulse SR regime, with the peak power of 600 MW in a single channel, for a four-channel 2-D array, we attained a 16-fold radiation intensity gain

Климатические изменения термических условий Карского моря за последние 40 лет

The paper discusses air (Ta) and sea surface temperature (SST) year-to-year variability due to warming of the Kara Sea, using the data from regular observations at the meteorological stations Roshydromet (GMS) in 1978–2017, NOAA optimum interpolation and reanalysis data. We use the methods of cluster, correlation analysis and Empirical Orthogonal Functions (EOF). We investigate possible cause and effect relationships of these changes with the variations of the wind field components, climatic indices and the sea ice concentration field. The cluster analysis of the three main EOF components has allowed us to identify four areas on the basis of the nature of changes of the water temperature anomalies field. The climatic changes in these areas, in the coastal and island zones of the Kara Sea have manifested themselves in the steady increase of the annual air temperature at GMS from 0,47–0,77 °C/10 years on the southwest coast to 1,33–1,49 °C/10 years in the north of the sea. This is equivalent to warming from 1,9 to 6,0 °C in the last 40 years. For the open sea the value of the Ta trend is about 1,22 °C/10 years, which corresponds to an increase in the average Ta by 4,9 °C in the last 40 years. This value is approximately 3 times greater than that for all the Northern hemisphere for the same period.Annualy, the maximal trend was observed in November and April mainly and exceeded 2–3 °C/10 years at some of the stations. We identify anomalously warm (2016 and 2012) and anomalously cold (1978, 1979, 1992 and 1998) years: the warmest year was 2012, the coldest — 1979. Positive SST trends were observed over all the sea area during the warm period of year (to 1 °C/10 years). SST increased to 2,4 °C, which is approximately 1,5 times greater than the corresponding SST values for the Northern hemisphere. The maximum SST trend (0,4 °C/10 years) was observed in the northwest and southwest parts of the sea. From June to August the trends of SST exceed the annual ones 1,5–2 times. Interannual SST and Ta variations are characterized by close correlation links. Until approximately 1998–2004 the warming was rather insignificant, and after that the growth rate of Ta and SST increased many fold. Apparently it indicates changes in the mode and the large-scale atmospheric circulation in the early 2000s. We also observed a trend of strengthening of the southern wind during the cold period of the year and the northern one — in the warm period (0,5–0,6 m/s in 40 years). It is shown that there is a close correlation between the Ta increase and the changes in the meridional component of the wind speed during the cold period of the year for all the sea areas. For the warm period it is statistically insignificant both for Ta and SST. For the cold season we observed a contribution of the large-scale mode of atmospheric circulation into the variability of V component of the wind speed. The conribution was expressed through the indeces NAO, SCAND, Pol/EUR, AZOR, ISL and the differences of ISLSIB. For the warm season this contribution is expressed through the NAO, SCAND and AO only. For the warm period we showed statistically significant correlation between the increase in SST, Ta and the processes parametrized by the AMO, EA/WR and AZOR indeces. For the cold period the indeces are AMO, Pol/Eur, SIB and ISL SIB. The interannual variations of the sea ice concentration field are characterized by close correlation with Ta changes both in the annual cycle and during the periods of ice cover formation and evolution (R = –0,7... –0,9). For these periods we showed statistically significant relationships between the first EOF mode fluctuations and two climatic indeces — AMO (R = 0,5) and Pol/Eur (R = 0,4). The relationships between the temporary variability of the sea ice concentration and the wind field characteristics are weaker and statistically significant only for the meridional component of the wind speed (R = –0,4).По данным срочных наблюдений на гидрометеорологических станциях Росгидромета за 1978–2017 гг., данных оптимальной интерполяции и реанализа NOAA выполнен анализ межгодовой изменчивости поверхностной температуры воды и воздуха в Карском море на современном этапе потепления климата. Методы кластерного, корреляционного анализа и аппарата эмпирических ортогональных функций использованы для определения пространственно-временной структуры поля температуры и районирования акватории по особенностям климатических изменений. Исследованы возможные причинно-следственные связи этих изменений с вариациями составляющих поля ветра, климатическими индексами и сплоченностью льда. В результате удалось уточнить количественную оценку тенденций и выявить региональные особенностей межгодовой изменчивости термических условий Карского моря

Оценка влияния наносекундных рентгеновских импульсов на функциональную активность митохондрий печени мышей

The effect of nanosecond pulses of X-ray (pulse repetition rate of 8—22 pulses per second, dose 0,3—1,8 mR per pulse) on the functional activity of isolated mitochondria of mice liver. The effects of changing the rate of oxygen consumption by mitochondria in different metabolic states of Chance and the degree of coupling of oxidation and phosphorylation were investigated. That effect depends on the parameters of exposure.Исследовано влияние рентгеновских импульсов наносекундной длительности (частота повторения 8—22 импульса в секунду, доза в импульсе 0,3—1,8 мР) на функциональную активность изолированных митохондрий печени мышей. Исследуемое воздействие изменяет скорость потребления кислорода митохондриями в различных метаболических состояниях по Чансу и степень сопряжения процессов окисления и фосфорилирования. Данный эффект зависит от параметров воздействия

Различия эфектов импульсно-периодического рентгеновского излучения в опухолевых клетках линии MOLT-4 и лимфоцитах периферической крови человека

Effects of ionizing radiation registered in cells after low dose irradiation are still poorly understood. Thus, the aim of this study was to analyze effects of pulsed X-rays on level of radiation-induced DNA double-strand breaks and their repair kinetics in cancer and normalhuman cells in vitro. Analysis of radiation-induced γH2AX and 53BP1 repair foci in MOLT-4 cells with lymphoblastic origin was used for assessment of DNA double-strand breaks (DSB) in these cells. Number of residual radiation-induced γH2AX and 53BP1 foci at 18 hafter irradiation depended on frequency of X-ray pulses: at 8 pulses per second effect was highest in MOLT-4 cells and lowest in peripheral blood lymphocytes. It suggests that pulsed X-rays with various frequencies could be used for target influence on cancer cells being lessdeleterious for normal human cells.Разработаны источники, способные генерировать импульсно-периодическое рентгеновское излучение (ИПРИ) в наносекундном диапазоне с возможностью изменения частоты повторения импульсов и дозы за импульс. Целью настоящего исследования стал анализ воздействия ИПРИ на уровень двунитевых разрывов ДНК в опухолевых и нормальных клетках человека в условиях in vitro. Для оценки уровня двунитевых разрывов ДНК и эффективности их репарации использовался метод анализа флуоресцентных фокусов белков репарации ДНК γH2AX и 53BP1 в клетках опухолевой линии MOLT-4, имеющей лимфобластное происхождение, после воздействия ИПРИ в условиях in vitro. Наибольший уровень фокусов γH2AX и 53BP1 через 18 ч после воздействия, являющийся маркером эффективности репарации ДНК, в клетках линии MOLT-4 отмечался при воздействии ИПРИ с частотой повторения импульсов 8 имп./с, при которой ранее в лимфоцитах наблюдалось наименьшее количество двунитевых разрывов ДНК. Полученные результаты указывают, что использование ИПРИ с различными частотами повторения импульсов может позволитьдифференцированно воздействовать на опухолевые клетки, незначительно повреждая при этом нормальные клетки человека

ВЛИЯНИЕ ИМПУЛЬСНО-ПЕРИОДИЧЕСКОГО РЕНТГЕНОВСКОГО ИЗЛУЧЕНИЯ НА КЛЕТКИ ОПУХОЛИ И КОСТНОГО МОЗГА МЫШЕЙ

The results of the effect of pulse-periodic X-ray exposure (PPXE) generated by Sinus-150 accelerator on tumor and normal cells of mice have been presented. Chromosomal aberrations (metaphase analysis) of bone marrow cells were studied. Using the cultured Lewis lung carcinoma cell lines, the level of apoptotic cells and cells with high concentration of active oxygen forms (AOF) was assessed by the flow cytofluorometry analysis (FACSCantoII, BD). In vivo X-ray radiation in the pulse-periodic mode lead to the moderate increase in chromosomal aberrations of bone marrow cells of mice. PPXE induced apoptotic death in Lewis lung carcinoma cells in vitro due to AOF production. Dose-effect relation was not observed at the irradiation doses 0.2–1.0 Gy. The data obtained show that further studies are necessary to justify the use of PPXE in tumor therapy.Представлены результаты изучения влияния импульсно-периодического рентгеновского излучения (ИПРИ), генерируемого уникальным источником «Синус-150» (Институт сильноточной электроники СО РАН, г. Томск), на опухолевые и нормальные клетки. Изучали хромосомные аберрации (метафазный анализ) клеток костного мозга мышей, облученных ИПРИ в режимах, обеспечивающих противоопухолевый эффект. На культурах клеток карциномы Льюис, облученных ИПРИ, оценивали уровень апоптоза клеток и клеток с высоким содержанием активных форм кислорода (АФК) методом проточной цитофлуориметрии (FACSCantoII, BD). При локальном облучении ИПРИ in vivo в режимах, вызывающих противоопухолевый эффект, наблюдается умеренное увеличение аберраций в хромосомах клеток костного мозга мышей. ИПРИ индуцирует процесс апоптотической гибели в клетках карциномы легких Льюис in vitro за счет продукции АФК. При этом в диапазоне 0,2–1,0 Гр не отмечается зависимости эффекта от дозы облучения. Полученные данные свидетельствуют о перспективности дальнейших исследований для обоснования использования ИПРИ в терапии опухолей

Действие наносекундного импульсно-периодического микроволнового излучения на процессы регенерации

The effects of pulse periodic microwaves (10 GHz, duration of pulse 100 ns, pulse repetition frequency 4—19 pps, peak power density 40—1 520 W/cm2 ) on the reparative regeneration of full-thickness skin wounds on mice was investigated. This effect depends on the pulse repetition frequency and peak power density.Исследовано влияние импульсно-периодического микроволнового излучения (10 ГГц, длительность импульсов 100 нс, частота повторения 4—19 импульсов в секунду, пиковая плотность потока мощности 40—1 520 Вт/см2 ) на репаративную регенерацию полнослойной кожной раны у мышей. Исследуемое воздействие может стимулировать заживление ран. Данный эффект зависит от частоты повторения импульсов и величины пиковой плотности потока мощности