Prostaglandin E2 reduces radiation-induced epithelial apoptosis through a mechanism involving AKT activation and bax translocation

Prostaglandin E(2) (PGE(2)) synthesis modulates the response to radiation injury in the mouse intestinal epithelium through effects on crypt survival and apoptosis; however, the downstream signaling events have not been elucidated. WT mice receiving 16,16-dimethyl PGE(2) (dmPGE(2)) had fewer apoptotic cells per crypt than untreated mice. Apoptosis in Bax(–/–) mice receiving 12 Gy was approximately 50% less than in WT mice, and the ability of dmPGE(2) to attenuate apoptosis was lost in Bax(–/–) mice. Positional analysis revealed that apoptosis in the Bax(–/–) mice was diminished only in the bax-expressing cells of the lower crypts and that in WT mice, dmPGE(2) decreased apoptosis only in the bax-expressing cells. The HCT-116 intestinal cell line and Bax(–/–) HCT-116 recapitulated the apoptotic response of the mouse small intestine with regard to irradiation and dmPGE(2). Irradiation of HCT-116 cells resulted in phosphorylation of AKT that was enhanced by dmPGE(2) through transactivation of the EGFR. Inhibition of AKT phosphorylation prevented the reduction of apoptosis by dmPGE(2) following radiation. Transfection of HCT-116 cells with a constitutively active AKT reduced apoptosis in irradiated cells to the same extent as in nontransfected cells treated with dmPGE(2). Treatment with dmPGE(2) did not alter bax or bcl-x expression but suppressed bax translocation to the mitochondrial membrane. Our in vivo studies indicate that there are bax-dependent and bax-independent radiation-induced apoptosis in the intestine but that only the bax-dependent apoptosis is reduced by dmPGE(2). The in vitro studies indicate that dmPGE(2), most likely by signaling through the E prostaglandin receptor EP(2), reduces radiation-induced apoptosis through transactivation of the EGFR and enhanced activation of AKT and that this results in reduced bax translocation to the mitochondria

Magnetic Resonance

Contains research objectives and reports on three research projects

A shortening of the life-cycle of major tropical cyclones

In this study a comprehensive picture of the changing intensity life cycle of major (Category 3 and higher) tropical cyclones (TCs) is presented. Over the past decades, the lifetime maximum intensity has increased, but there has also been a significant decrease in duration of time spent at intensities greater than Category 1. These compensating effects have maintained a stable global mean‐accumulated cyclone energy of individual major TCs. The global mean duration of major TCs has shortened by about 1 day from 1982 to 2018. There has been both faster intensification (Categories 1 to 3) and weakening (Categories 3 to 1) by about 40%. The probabilities of rapid intensification and rapid weakening have both risen in the period 2000–2018 compared to 1982–1999. A statistically significant anticorrelation is found between the lifetime maximum intensity and the following duration of the final weakening. This suggests an element of self‐regulation of TC life cycles

Численное моделирование теплофизических условий реализации режима циркулирующего кипящего слоя применительно к топкам котлов

Актуальность проведения исследований, направленных на совершенствование методов численного анализа аэротермохимических процессов в топках с циркулирующим кипящим слоем на основе компьютерного математического моделирования, является весьма высокой для обоснования основных проектно-конструкторских и режимно-эксплуатационных параметров при создании котлов с ЦКС. С помощью наработанных численных расчетов возможно не только правильно осмыслять и понимать физические явления, наблюдаемые, например, на экспериментальных установках, но и в некоторых случаях заменить физический или натуральный эксперимент компьютерным как более дешевым и менее трудоемким.The relevance of research aimed at improving the methods of numerical analysis of aerothermochemical processes in furnaces with a circulating fluidized bed based on computer mathematical modeling is very high for justifying the main design and operational parameters creating boilers with CFB. With the help of accumulated numerical calculations, it is possible not only to correctly comprehend and understand the physical phenomena observed, for example, in experimental installations, but also in some cases to replace a physical or natural experiment with a computer one as cheaper and less time-consuming

Magnetic Resonance

Contains research objectives and reports on three research projects

Frailty and Cardiovascular Disease

Cardiovascular disease (CVD) comprises a vast spectrum of disease states ranging from hypertension (HTN) to valvular heart disease (VHD). CVD is known to be the leading cause of morbidity, mortality, and health‐care expenditure throughout the world. According to the World Health Organization, coronary artery disease (CAD) and stroke, both subsets of CVD, are the world’s biggest killers, accounting for a combined 15 million deaths in 2015. These diseases have remained the leading causes of death globally in the last 15 years. In 2010, CAD alone was projected to cost the U.S. $108.9 billion including the cost of health‐care services, medications, and lost productivity. The presence of frailty significantly worsens outcomes for patients suffering from CAD. With just this one example of how frailty affects CVD, it is clear that understanding the impact of frailty upon patients afflicted with the spectrum of cardiovascular disease is integral for the care of this very significant patient population