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991.
Bridget Pratt Khin Maung Lwin Deborah Zion Francois Nosten Bebe Loff Phaik Yeong Cheah 《Developing world bioethics》2015,15(1):18-26
It has been suggested that community advisory boards (CABs) can play a role in minimising exploitation in international research. To get a better idea of what this requires and whether it might be achievable, the paper first describes core elements that we suggest must be in place for a CAB to reduce the potential for exploitation. The paper then examines a CAB established by the Shoklo Malaria Research Unit under conditions common in resource‐poor settings – namely, where individuals join with a very limited understanding of disease and medical research and where an existing organisational structure is not relied upon to serve as the CAB. Using the Tak Province Border Community Ethics Advisory Board (T‐CAB) as a case study, we assess the extent to which it might be able to take on a role minimising exploitation were it to decide to do so. We investigate whether, after two years in operation, T‐CAB is capable of assessing clinical trials for exploitative features and addressing those found to have them. The findings show that, although T‐CAB members have gained knowledge and developed capacities that are foundational for one‐day taking on a role to reduce exploitation, their ability to critically evaluate studies for the presence of exploitative elements has not yet been strongly demonstrated. In light of this example, we argue that CABs may not be able to perform such a role for a number of years after initial formation, making it an unsuitable responsibility for many short‐term CABs. 相似文献
992.
Satellite remote sensing observations allow the ocean surface to be sampled synoptically over large spatio-temporal scales. The images provided from visible and thermal infrared satellite observations are widely used in physical, biological, and ecological oceanography. The present work proposes a method to understand the multi-scaling properties of satellite products such as the Chlorophyll-a (Chl-a), and the Sea Surface Temperature (SST), rarely studied. The specific objectives of this study are to show how the small scale heterogeneities of satellite images can be characterised using tools borrowed from the fields of turbulence. For that purpose, we show how the structure function, which is classically used in the frame of scaling time series analysis, can be used also in 2D. The main advantage of this method is that it can be applied to process images which have missing data. Based on both simulated and real images, we demonstrate that coarse-graining (CG) of a gradient modulus transform of the original image does not provide correct scaling exponents. We show, using a fractional Brownian simulation in 2D, that the structure function (SF) can be used with randomly sampled couple of points, and verify that 1 million of couple of points provides enough statistics. 相似文献
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Harish Srinivasan Yves Allory Martin Sill Dimitri Vordos Mohamed Saiel Saeed Alhamdani Francois Radvanyi Jörg D. Hoheisel Christoph Schröder 《Proteomics》2014,14(11):1333-1342
About 70% of newly diagnosed cases of bladder cancer are low‐stage, low‐grade, non muscle‐invasive. Standard treatment is transurethral resection. About 60% of the tumors will recur, however, and in part progress to become invasive. Therefore, surveillance cystoscopy is performed after resection. However, in the USA and Europe alone, about 54 000 new patients per year undergo repeated cystoscopies over several years, who do not experience recurrence. Analysing in a pilot study resected tumors from patients with (n = 19) and without local recurrence (n = 6) after a period of 5 years by means of an antibody microarray that targeted 724 cancer‐related proteins, we identified 255 proteins with significantly differential abundance. Most are involved in the regulation and execution of apoptosis and cell proliferation. A multivariate classifier was constructed based on 20 proteins. It facilitates the prediction of recurrence with a sensitivity of 80% and a specificity of 100%. As a measure of overall accuracy, the area under the curve value was found to be 91%. After validation in additional sample cohorts with a similarly long follow‐up, such a signature could support decision making about the stringency of surveillance or even different treatment options. 相似文献
996.
Identification of Akt association and oligomerization domains of the Akt kinase coactivator TCL1 下载免费PDF全文
Künstle G Laine J Pierron G Kagami Si S Nakajima H Hoh F Roumestand C Stern MH Noguchi M 《Molecular and cellular biology》2002,22(5):1513-1525
Serine/threonine kinase Akt/protein kinase B, the cellular homologue of the transforming viral oncogene v-Akt, plays a central role in the regulation of cell survival and proliferation. We have previously demonstrated that the proto-oncogene TCL1 is an Akt kinase coactivator. TCL1 binds to Akt and mediates the formation of oligomeric TCL1-Akt high-molecular-weight protein complexes in vivo. Within these protein complexes, Akt is preferentially phosphorylated and activated. The MTCP1/TCL1/TCL1b oncogene activation is the hallmark of human T-cell prolymphocytic leukemia (T-PLL), a form of adult leukemia. In the present study, using a PCR-generated random TCL1 library combined with a yeast two-hybrid screening detecting loss of interaction, we identified D16 and I74 as amino acid residues mediating the association of TCL1 with Akt. Based on molecular modeling, we determined that the beta C-sheet of TCL1 is essential for TCL1 homodimerization. Studies with mammalian overexpression systems demonstrated that both Akt association and oligomerization domains of TCL1 are distinct functional domains. In vitro kinase assays and overexpression experiments in mammalian cells demonstrated that both TCL1-Akt interaction and oligomerization of TCL1 were required for TCL1-induced Akt activation and substrate phosphorylation. Assays for mitochondrial permeability transition, nuclear translocation, and cell recovery demonstrated that both Akt association and homodimerization of TCL1 are similarly needed for the full function of TCL1 as an Akt kinase coactivator in vivo. The results demonstrate the structural basis of TCL1-induced activation of Akt, which causes human T-PLL. 相似文献
997.
Ma X Abboud FM Chapleau MW 《American journal of physiology. Regulatory, integrative and comparative physiology》2002,283(5):R1033-R1040
Studies of genetically modified mice provide a powerful approach to investigate consequences of altered gene expression in physiological and pathological states. The goal of the present study was to characterize afferent, central, and efferent components of the baroreceptor reflex in anesthetized Webster 4 mice. Baroreflex and baroreceptor afferent functions were characterized by measuring changes in renal sympathetic nerve activity (RSNA) and aortic depressor nerve activity (ADNA) in response to nitroprusside- and phenylephrine-induced changes in arterial pressure. The data were fit to a sigmoidal logistic function curve. Baroreflex diastolic pressure threshold (P(th)), the pressure at 50% inhibition of RSNA (P(mid)), and baroreflex gain (maximum slope) averaged 74 +/- 5 mmHg, 101 +/- 3 mmHg, and 2.30 +/- 0.54%/mmHg, respectively (n = 6). The P(th), P(mid), and gain for the diastolic pressure-ADNA relation (baroreceptor afferents) were similar to that observed for the overall reflex averaging 79 +/- 9 mmHg, 101 +/- 4 mmHg, and 2.92 +/- 0.53%/mmHg, respectively (n = 5). The central nervous system mediation of the baroreflex and the chronotropic responsiveness of the heart to vagal efferent activity were independently assessed by recording responses to electrical stimulation of the left ADN and the peripheral end of the right vagus nerve, respectively. Both ADN and vagal efferent stimulation induced frequency-dependent decreases in heart rate and arterial pressure. The heart rate response to ADN stimulation was nearly abolished in mice anesthetized with pentobarbital sodium (n = 4) compared with mice anesthetized with ketamine-acepromazine (n = 4), whereas the response to vagal efferent stimulation was equivalent under both types of anesthesia. Application of these techniques to studies of genetically manipulated mice can be used to identify molecular mechanisms of baroreflex function and to localize altered function to afferent, central, or efferent sites. 相似文献
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Inga Preuss Marie-Gabrielle Ludwig Birgit Baumgarten Frederic Bassilana Francois Gessier Klaus Seuwen Andreas W. Sailer 《Biochemical and biophysical research communications》2014
Oxysterols such as 7 alpha, 25-dihydroxycholesterol (7α,25-OHC) are natural ligands for the Epstein-Barr virus (EBV)-induced gene 2 (EBI2, aka GPR183), a G protein-coupled receptor (GPCR) highly expressed in immune cells and required for adaptive immune responses. Activation of EBI2 by specific oxysterols leads to chemotaxis of B cells in lymphoid tissues. While the ligand gradient necessary for this critical process of the adaptive immune response is established by a stromal cells subset here we investigate the involvement of the oxysterol/EBI2 system in the innate immune response. First, we show that primary human macrophages express EBI2 and the enzymes needed for ligand production such as cholesterol 25-hydroxylase (CH25H), sterol 27-hydroxylase (CYP27A1), and oxysterol 7α-hydroxylase (CYP7B1). Furthermore, challenge of monocyte-derived macrophages with lipopolysaccharides (LPS) triggers a strong up-regulation of CH25H and CYP7B1 in comparison to a transient increase in EBI2 expression. Stimulation of EBI2 expressed on macrophages leads to calcium mobilization and to directed cell migration. Supernatants of LPS-stimulated macrophages are able to stimulate EBI2 signaling indicating that an induction of CH25H, CYP27A1, and CYP7B1 results in an enhanced production and release of oxysterols into the cellular environment. This is a study characterizing the oxysterol/EBI2 pathway in primary monocyte-derived macrophages. Given the crucial functional role of macrophages in the innate immune response these results encourage further exploration of a possible link to systemic autoimmunity. 相似文献
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