26 research outputs found

    Propagation of an Earth-directed coronal mass ejection in three dimensions

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    Solar coronal mass ejections (CMEs) are the most significant drivers of adverse space weather at Earth, but the physics governing their propagation through the heliosphere is not well understood. While stereoscopic imaging of CMEs with the Solar Terrestrial Relations Observatory (STEREO) has provided some insight into their three-dimensional (3D) propagation, the mechanisms governing their evolution remain unclear due to difficulties in reconstructing their true 3D structure. Here we use a new elliptical tie-pointing technique to reconstruct a full CME front in 3D, enabling us to quantify its deflected trajectory from high latitudes along the ecliptic, and measure its increasing angular width and propagation from 2-46 solar radii (approximately 0.2 AU). Beyond 7 solar radii, we show that its motion is determined by an aerodynamic drag in the solar wind and, using our reconstruction as input for a 3D magnetohydrodynamic simulation, we determine an accurate arrival time at the Lagrangian L1 point near Earth.Comment: 5 figures, 2 supplementary movie

    Peritoneal VEGF-A expression is regulated by TGF-ÎČ1 through an ID1 pathway in women with endometriosis

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    VEGF-A, an angiogenic factor, is increased in the peritoneal fluid of women with endometriosis. The cytokine TGF-ÎČ1 is thought to play a role in the establishment of endometriosis lesions. Inhibitor of DNA binding (ID) proteins are transcriptional targets of TGF-ÎČ1 and ID1 has been implicated in VEGF-A regulation during tumor angiogenesis. Herein, we determined whether peritoneal expression of VEGF-A is regulated by TGF-ÎČ1 through the ID1 pathway in women with endometriosis. VEGF-A was measured in peritoneal fluid by ELISA (n = 16). VEGF-A and ID1 expression was examined in peritoneal biopsies (n = 13), and primary peritoneal and immortalized mesothelial cells (MeT5A) by immunohistochemistry, qRT-PCR and ELISA. VEGF-A was increased in peritoneal fluid from women with endometriosis and levels correlated with TGF-ÎČ1 concentrations (P < 0.05). VEGF-A was immunolocalized to peritoneal mesothelium and TGF-ÎČ1 increased VEGFA mRNA (P < 0.05) and protein (P < 0.05) in mesothelial cells. ID1 was increased in peritoneum from women with endometriosis and TGF-ÎČ1 increased concentrations of ID1 mRNA (P < 0.05) in mesothelial cells. VEGF-A regulation through ID1 was confirmed by siRNA in MeT5A cells (P < 0.05). Our data supports role for ID1 in the pathophysiology of endometriosis, as an effector of TGFÎČ1 dependent upregulation of VEGF-A, and highlights a novel potential therapeutic target

    An international review of tobacco smoking in the medical profession: 1974–2004

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    Background\ud Tobacco smoking by physicians represents a contentious issue in public health, and regardless of what country it originates from, the need for accurate, historical data is paramount. As such, this article provides an international comparison of all modern literature describing the tobacco smoking habits of contemporary physicians.\ud \ud Methods\ud A keyword search of appropriate MeSH terms was initially undertaken to identify relevant material, after which the reference lists of manuscripts were also examined to locate further publications.\ud \ud Results\ud A total of 81 English-language studies published in the past 30 years met the inclusion criteria. Two distinct trends were evident. Firstly, most developed countries have shown a steady decline in physicians' smoking rates during recent years. On the other hand, physicians in some developed countries and newly-developing regions still appear to be smoking at high rates. The lowest smoking prevalence rates were consistently documented in the United States, Australia and the United Kingdom. Comparison with other health professionals suggests that fewer physicians smoke when compared to nurses, and sometimes less often than dentists.\ud \ud Conclusion\ud Overall, this review suggests that while physicians' smoking habits appear to vary from region to region, they are not uniformly low when viewed from an international perspective. It is important that smoking in the medical profession declines in future years, so that physicians can remain at the forefront of anti-smoking programs and lead the way as public health exemplars in the 21st century

    The Peritoneum Is Both a Source and Target of TGF-ÎČ in Women with Endometriosis

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    Transforming growth factor-ÎČ (TGF-ÎČ) is believed to play a major role in the aetiology of peritoneal endometriosis. We aimed to determine if the peritoneum is a source of TGF-ÎČ and if peritoneal TGF-ÎČ expression, reception or target genes are altered in women with endometriosis. Peritoneal fluid, peritoneal bushings and peritoneal biopsies were collected from women with and without endometriosis. TGF-ÎČ1, 2 and 3 protein concentrations were measured in the peritoneal fluid. TGF-ÎČ1 was measured in mesothelial cell conditioned media. Control peritoneum and peritoneum prone to endometriosis (within Pouch of Douglas) from women without disease (n = 16) and peritoneum distal and adjacent to endometriosis lesions in women with endometriosis (n = 15) and were analysed for TGF-ÎČ expression, reception and signalling by immunohistochemistry, qRT-PCR and a TGF-ÎČ signalling PCR array. TGF-ÎČ1 was increased in the peritoneal fluid of women with endometriosis compared to those without disease (P<0.05) and peritoneal mesothelial cells secrete TGF-ÎČ1 in-vitro. In women with endometriosis, peritoneum from sites adjacent to endometriosis lesions expressed higher levels of TGFB1 mRNA when compared to distal sites (P<0.05). The TGF-ÎČ-stimulated Smad 2/3 signalling pathway was active in the peritoneum and there were significant increases (P<0.05) in expression of genes associated with tumorigenesis (MAPK8, CDC6), epithelial-mesenchymal transition (NOTCH1), angiogenesis (ID1, ID3) and neurogenesis (CREB1) in the peritoneum of women with endometriosis. In conclusion, the peritoneum, and in particular, the peritoneal mesothelium, is a source of TGF-ÎČ1 and this is enhanced around endometriosis lesions. The expression of TGF-ÎČ-regulated genes is altered in the peritoneum of women with endometriosis and this may promote an environment favorable to lesion formation

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

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    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field
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