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91.
A. Dutier 《Médecine Nucléaire》2013,37(8):310-312
Nuclear medicine physicians are very involved in French's oncology announcement procedure. However, their role needs to be analysed and evaluated. Before diagnosis’ announcement, information provided by nuclear medicine physicians are never neutral for patients. Information must not increase patient's anxiety or false patient's sense of reassurance. In this context, it seems necessary to engage in ethical reflexions about nuclear medicine physicians communication challenges. 相似文献
92.
Many aquatic ecosystems are sustained by detrital subsidies of leaf litter derived from exogenous sources. Although numerous studies have examined the effects of litter species richness and identity on decomposition processes, it remains unclear how these effects extend to associated invertebrate communities or how these effects vary spatially according to local environmental context. Using field enrichment experiments, we assessed how the species richness, assemblage composition, and supply of detrital litter resources interact to affect benthic communities of three temperate Australian estuarine mudflats. Our experiments utilized eight litter sources that are presently experiencing human‐mediated changes in their supply to estuarine mudflats. Contrary to predictions, we did not detect effects of the species richness of detrital mixtures on benthic communities. Macroinvertebrate community structure and, in particular, abundance were, instead, influenced by the assemblage composition of detrital mixtures. At two of the three sites, plots receiving the most labile detrital mix, containing the ephemeral algae Chaetomorpha and Ulva, supported the fewest macroinvertebrates of all the experimental enrichments. The large effect of detrital mix identity on macroinvertebrate communities is of concern given present trends of proliferation of macroalgae at the expense of more refractory seagrasses and marsh grasses. As such environmental degradation continues, it will be important to more fully understand under what environmental contexts such compositional changes in detrital resources will have the most detrimental effects on important prey resources for commercially important fish and wading shorebirds. 相似文献
93.
To examine how the major elements of global change affect herbivory in agroecosystems, a multifactorial experiment was conducted where soybeans were grown at two levels of carbon dioxide and temperature, including those predicted for 2050, under otherwise normal field conditions. Japanese beetles (Popillia japonica Newman) were enclosed on foliage for 24 h, after which the beetle survivorship, total and per capita leaf consumption, and leaf protease inhibitor activity were measured. The direct effect of temperature on beetle consumption and survivorship also was measured under controlled environmental conditions. No differences in total foliage consumption were observed; however, beetles forced to feed at elevated temperature in the field demonstrated greater per capita consumption and reduced survivorship compared to beetles feeding at ambient temperature. Survivorship was also greater for beetles that consumed foliage grown under elevated CO2, but there were no interactive effects of CO2 and temperature, and no differences in leaf chemistry were resolved. Leaf consumption by beetles increased strongly with increasing temperature up to ~37° C, above which increased mortality caused a precipitous decrease in consumption. An empirical model based on the temperature dependence of leaf consumption and flight suggests that the 3.5°C increase in temperature predicted for 2050 will increase the optimal feeding window for the Japanese beetle by 290%. Elevated temperature and CO2 operating independently have the potential to greatly increase foliage damage to soybean by chewing insects, such as Popillia japonica, potentially affecting crop yields. 相似文献
94.
Analysis of monosomy‐3 in immunomagnetically isolated circulating melanoma cells in uveal melanoma patients
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Aysegül Tura Hartmut Merz Mihaela Reinsberg Matthias Lüke Martine J. Jager Salvatore Grisanti Julia Lüke 《Pigment cell & melanoma research》2016,29(5):583-589
Monosomy‐3 in primary uveal melanoma (UM) is associated with a high risk of metastasis and mortality. Although circulating melanoma cells (CMC) can be found in most UM patients, only approximately 50% of the patients develop metastases. We utilized a novel immuno‐FISH assay to detect chromosome‐3 in intact CMC isolated by dual immunomagnetic enrichment. Circulating melanoma cells were detected in 91% of the patients (n = 44) with primary non‐metastatic UM, of which 58% were positive for monosomy‐3. The monosomy‐3 status of CMC corresponded to the monosomy‐3 status of the primary tumor in 10 of the 11 patients where this could be tested. Monosomy‐3 in the CMC was associated with an advanced tumor stage (P = 0.046) and was detected in all four patients who developed metastasis within the follow‐up period of 4 yr. This non‐invasive technique may enable the identification of UM patients at risk for metastasis particularly when a primary tumor specimen is unavailable. 相似文献
95.
Development of immobilized Sn4+ affinity chromatography material for highly selective enrichment of phosphopeptides
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In this work, we first immobilized tin(IV) ion on polydopamine‐coated magnetic graphene (magG@PDA) to synthesize Sn4+‐immobilized magG@PDA (magG@PDA‐Sn4+) and successfully applied the material to highly selective enrichment of phosphopeptides. The material gathered the advantages of large surface area of graphene, superparamagnetism of Fe3O4, good hydrophilicity and biocompatibility of polydopamine, and strong interaction between Sn4+ and phosphopeptides. The enrichment performance of magG@PDA‐Sn4+ toward phosphopeptides from digested β‐casein at different concentrations, with and without added digested BSA was investigated and compared with magG@PDA‐Ti4+. The results showed high selectivity and sensitivity of the Sn4+‐IMAC material toward phosphopeptides, as good as the Ti4+‐IMAC material. Finally, magG@PDA‐Sn4+ was applied to the analysis of endogenous phosphopeptides from a real sample, human saliva, with both MALDI‐TOF MS and nano‐LC‐ESI‐MS/MS. The results indicated that the as‐synthesized Sn4+‐IMAC material not only has good enrichment performance, but also could serve as a supplement to the Ti4+‐IMAC material and expand the phosphopeptide coverage enriched by the single Ti4+‐IMAC material, demonstrating the broad application prospects of magG@PDA‐Sn4+ in phosphoproteome research. 相似文献
96.
97.
Meisha Holloway‐Phillips Lucas A. Cernusak Margaret Barbour Xin Song Alexander Cheesman Niels Munksgaard Hilary Stuart‐Williams Graham D. Farquhar 《Plant, cell & environment》2016,39(11):2414-2427
The process of evaporation results in the fractionation of water isotopes such that the lighter 16O isotope preferentially escapes the gas phase leaving the heavier 18O isotope to accumulate at the sites of evaporation. This applies to transpiration from a leaf with the degree of fractionation dependent on a number of environmental and physiological factors that are well understood. Nevertheless, the 18O enrichment of bulk leaf water is often less than that predicted for the sites of evaporation. The advection of less enriched water in the transpiration stream has been suggested to limit the back diffusion of enriched evaporative site water (Péclet effect); however, evidence for this effect has been varied. In sampling across a range of species with different vein densities and saturated water contents, we demonstrate the importance of accounting for the relative ‘pool’ sizes of the vascular and mesophyll water for the interpretation of a Péclet effect. Further, we provide strong evidence for a Péclet signal within the xylem that if unaccounted for can lead to confounding of the estimated enrichment within the mesophyll water. This has important implications for understanding variation in the effective path length of the mesophyll and hence potentially the δ18O of organic matter. 相似文献
98.
Marcello Locatelli Roberta Cifelli Giuseppe Carlucci Annalisa Romagnoli 《Journal of enzyme inhibition and medicinal chemistry》2016,31(1):106-111
A new and specific HPLC–DAD method for the direct determination of Prulifloxacin and its active metabolite, Ulifloxacin, in human plasma has been developed. Plasma samples were analysed after a simple solid phase extraction (SPE) clean-up using a new HILIC stationary phase based high-performance liquid chromatography (HPLC) column and an ammonium acetate buffer (5?mM, pH 5.8)/acetonitrile (both with 1% Et3N, v/v) mobile phase in isocratic elution mode, with Danofloxacin as the internal standard. Detection was performed using DAD from 200 to 500?nm and quantitative analyses were carried out at 278?nm. The LOQ of the method was 1?μg/mL of the cited analytes and the calibration curve showed a good linearity up to 25?μg/mL. For both analytes the precision (RSD%) and the trueness (bias%) of the method fulfil with International Guidelines. The method was applied for stability studies, at three QC concentration levels, in human plasma samples stored at different temperature of?+?25,?+?4 and ?20?°C in order to evaluate plasma stability profiles. 相似文献
99.
Merve Sasmaz Bunyamin Akgül Derya Yıldırım 《International journal of phytoremediation》2016,18(1):69-76
This study investigated mercury (Hg) uptake and transport from the soil to different plant parts by documenting the distribution and accumulation of Hg in the roots and shoots of 12 terrestrial plant species, all of which grow naturally in surface soils of the Gumuskoy Pb-Ag mining area. Plant samples and their associated soils were collected and analyzed for Hg content by ICP-MS. Mean Hg values in the soils, roots, and shoots of all plants were 6.914, 460, and 206 µg kg?1, respectively and lower than 1. The mean enrichment factors for the roots (ECR) and shoots (ECS) of these plants were 0.06 and 0.09, respectively and lower than 1. These results show that the roots of the studied plants prevented Hg from reaching the aerial parts of the plants. The mean translocation factor (TLF) was 1.29 and higher than 1. The mean TLF values indicated that all 12 plant species had the ability to transfer Hg from the roots to the shoots but that transfer was more efficient in plants with higher ECR and ECS. Therefore, these plants could be useful for the biomonitoring of environmental pollution and for rehabilitating areas contaminated by Hg. 相似文献
100.
Chi Yuet X’avia Chan Marina A. Gritsenko Richard D. Smith 《Expert review of proteomics》2016,13(4):421-433
Protein phosphorylation is a fundamental regulatory mechanism in many cellular processes and aberrant perturbation of phosphorylation has been implicated in various human diseases. Kinases and their cognate inhibitors have been considered as hotspots for drug development. Therefore, the emerging tools, which enable a system-wide quantitative profiling of phosphoproteome, would offer a powerful impetus in unveiling novel signaling pathways, drug targets and/or biomarkers for diseases of interest. This review highlights recent advances in phosphoproteomics, the current state of the art of the technologies and the challenges and future perspectives of this research area. Finally, some exemplary applications of phosphoproteomics in diabetes research are underscored. 相似文献