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151.
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Cathy Zhou Zilong Yuan Weijie Ma Lihong Qi Angelique Mahavongtrakul Ying Li Hong Li Jay Gong Reggie R. Fan Jin Li Michael Molmen Travis A. Clark Dean Pavlick Garrett M. Frampton Brady Forcier Elizabeth H. Moore David K. Shelton Matthew Cooke Siraj M. Ali Vincent A. Miller Jeffrey P. Gregg Philip J. Stephens Tianhong Li 《Journal of hematology & oncology》2018,11(1):129
Background
This retrospective study was undertaken to determine if the plasma circulating tumor DNA (ctDNA) level and tumor biological features in patients with advanced solid tumors affected the detection of genomic alterations (GAs) by a plasma ctDNA assay.Method
Cell-free DNA (cfDNA) extracted from frozen plasma (N?=?35) or fresh whole blood (N?=?90) samples were subjected to a 62-gene hybrid capture-based next-generation sequencing assay FoundationACT. Concordance was analyzed for 51 matched FoundationACT and FoundationOne (tissue) cases. The maximum somatic allele frequency (MSAF) was used to estimate the amount of tumor fraction of cfDNA in each sample. The detection of GAs was correlated with the amount of cfDNA, MSAF, total tumor anatomic burden (dimensional sum), and total tumor metabolic burden (SUVmax sum) of the largest ten tumor lesions on PET/CT scans.Results
FoundationACT detected GAs in 69 of 81 (85%) cases with MSAF >?0. Forty-two of 51 (82%) cases had ≥?1 concordance GAs matched with FoundationOne, and 22 (52%) matched to the National Comprehensive Cancer Network (NCCN)-recommended molecular targets. FoundationACT also detected 8 unique molecular targets, which changed the therapy in 7 (88%) patients who did not have tumor rebiopsy or sufficient tumor DNA for genomic profiling assay. In all samples (N?=?81), GAs were detected in plasma cfDNA from cancer patients with high MSAF quantity (P?=?0.0006) or high tumor metabolic burden (P?=?0.0006) regardless of cfDNA quantity (P?=?0.2362).Conclusion
This study supports the utility of using plasma-based genomic assays in cancer patients with high plasma MSAF level or high tumor metabolic burden.154.
Chromosomal Localization of Three Human Dual Specificity Phosphatase Genes (DUSP4, DUSP6, and DUSP7)
Anna Smith Cathy Price Martin Cullen Marco Muda Andrea King Bradford Ozanne Steve Arkinstall Alan Ashworth 《Genomics》1997,42(3):524
Mitogen-activated protein (MAP) kinase phosphatases constitute a growing family of dual specificity phosphatases thought to play a role in the dephosphorylation and inactivation of MAP kinases and are therefore likely to be important in the regulation of diverse cellular processes such as proliferation, differentiation, and apoptosis. For this reason it has been suggested that MAP kinase phosphatases may be tumor suppressors. We have determined the chromosomal locations of three human dual specificity phosphatase genes by fluorescencein situhybridization and radiation hybrid mapping. The genes were localized to three different chromosomes,MKP2(DUSP4) to 8p11–p12,MKP3(DUSP6) to 12q22–q23, andMKPX(DUSP7) to 3p21. This will allow the potential roles of these genes in disease processes to be evaluated. 相似文献
155.
Deborah Hemming Dan Yakir Per Ambus Mika Aurela Cathy Besson Kevin Black Nina Buchmann Regis Burlett Alessandro Cescatti Robert Clement Patrick Gross Andr Granier Thomas Grünwald Katarina Havrankova Dalibor Janous Ivan A. Janssens Alexander Knohl Barbara K
stner Andrew Kowalski Tuomas Laurila Catarina Mata Barbara Marcolla Giorgio Matteucci John Moncrieff Eddy J. Moors Bruce Osborne Joo Santos Pereira Mari Pihlatie Kim Pilegaard Francesca Ponti Zuzana Rosova Federica Rossi Andrea Scartazza Timo Vesala 《Global Change Biology》2005,11(7):1065-1093
We present carbon stable isotope, δ13C, results from air and organic matter samples collected during 98 individual field campaigns across a network of Carboeuroflux forest sites in 2001 (14 sites) and 2002 (16 sites). Using these data, we tested the hypothesis that δ13C values derived from large‐scale atmospheric measurements and models, which are routinely used to partition carbon fluxes between land and ocean, and potentially between respiration and photosynthesis on land, are consistent with directly measured ecosystem‐scale δ13C values. In this framework, we also tested the potential of δ13C in canopy air and plant organic matter to record regional‐scale ecophysiological patterns. Our network estimates for the mean δ13C of ecosystem respired CO2 and the related ‘discrimination’ of ecosystem respiration, δer and Δer, respectively, were ?25.6±1.9‰ and 17.8 ±2.0‰ in 2001 and ?26.6±1.5‰ and 19.0±1.6‰ in 2002. The results were in close agreement with δ13C values derived from regional‐scale atmospheric measurement programs for 2001, but less so in 2002, which had an unusual precipitation pattern. This suggests that regional‐scale atmospheric sampling programs generally capture ecosystem δ13C signals over Europe, but may be limited in capturing some of the interannual variations. In 2001, but less so in 2002, there were discernable longitudinal and seasonal trends in δer. From west to east, across the network, there was a general enrichment in 13C (~3‰ and ~1‰ for the 2 years, respectively) consistent with increasing Gorczynski continentality index for warmer and drier conditions. In 2001 only, seasonal 13C enrichment between July and September, followed by depletion in November (from about ?26.0‰ to ?24.5‰ to ?30.0‰), was also observed. In 2001, July and August δer values across the network were significantly related to average daytime vapor pressure deficit (VPD), relative humidity (RH), and, to a lesser degree, air temperature (Ta), but not significantly with monthly average precipitation (Pm). In contrast, in 2002 (a much wetter peak season), δer was significantly related with Ta, but not significantly with VPD and RH. The important role of plant physiological processes on δer in 2001 was emphasized by a relatively rapid turnover (between 1 and 6 days) of assimilated carbon inferred from time‐lag analyses of δer vs. meteorological parameters. However, this was not evident in 2002. These analyses also noted corresponding diurnal cycles of δer and meteorological parameters in 2001, indicating a rapid transmission of daytime meteorology, via physiological responses, to the δer signal during this season. Organic matter δ13C results showed progressive 13C enrichment from leaves, through stems and roots to soil organic matter, which may be explained by 13C fractionation during respiration. This enrichment was species dependent and was prominent in angiosperms but not in gymnosperms. δ13C values of organic matter of any of the plant components did not well represent short‐term δer values during the seasonal cycle, and could not be used to partition ecosystem respiration into autotrophic and heterotrophic components. 相似文献
156.
James D. Tucker Karen J. Sorensen Cathy S. Chu David O. Nelson Marilyn J. Ramsey Cesare Urlando John A. Heddle 《Mutation research》1998,400(1-2):321-335
The dichotomy between the doses at which experimental measurements of genetic effects can be made and the doses to which people are exposed is often different by two or more orders of magnitude. This presents a significant problem when determining the effects of low doses of radiation or chemicals. The solution has usually involved extrapolating the data by curve-fitting or by applying theoretical considerations. Both approaches are unsatisfactory due to uncertainties of the assumptions used in each process. The alternative solution has been to increase the sample size enormously at the lower doses. This is impractical beyond a certain point due to the variation in the spontaneous frequency and the need to quadruple the sample size for a doubling of precision. The development of new methods for measuring stable genetic effects, however, permits a simple and effective approach to this problem: if the genetic events being detected have no effect on survival, i.e., are selectively neutral, then the effects of multiple independent treatments will be additive. If the independent treatments are identical, then the effect of each is easily calculated by dividing the total effect by the number of treatments. Here we report a limited test of this approach using mice. Chromosome aberrations induced in lymphocytes and Dlb-1 mutations induced in the small intestine were measured after daily doses of 0.64, 1.85 or 5.5 cGy 137Cs gamma rays administered for 21, 42 or 63 days. The dose response curve for chromosome translocations obtained in this way, combined with the data from single larger acute doses, shows no evidence for a threshold over a 500-fold dose range. Dlb-1 mutations were increased at each dose and time but the results do not permit reliable extrapolations. The results suggest that translocations might be useful for quantifying the effect of doses below 0.05 cGy and that the effect of dose rate and dose fractionation at much lower doses than reported here could be investigated. 相似文献
157.
We investigated the effect of the number of oxyethylene groups (polymer molecular weight) and the interchain binding and/or entanglements of methoxy-terminated-poly(ethylene glycol) (m-PEG) brushes on their ability to adsorb to living malignant melanoma B16F10 cells. We used the atomic force microscope colloid probe method to determine the adhering ability of the m-PEG brushes to the cells, as the magnitude of the adhesion force between the m-PEG modified particles and the living cells in a physiological buffer was related to the binding strength of the m-PEGs to the cells. We saw that m-PEG brushes (average molecular weights 330, 1900, and 5000 g/mol), which were chemically attached to silica particles, may bind to living B16F10 cells. The binding of m-PEGs to living B16F10 cells increased as the oxyethylene chain length of the m-PEGs increased, if the m-PEGs had a low degree of entanglements or little inter-m-PEG chain binding. A high degree of entanglements or interchain binding decreased the ability of an m-PEG chain to bind to a living cell. The effect of m-PEG (molecular weight 1900 g/mol) being present at cell surfaces for 24 h was also seen not to induce the death of the cells or affect their growth. 相似文献
158.
159.
Nahid Shokri Bousjein Morgan Staines Cathy Vo Natalie Puiu Carmen R. B. da Silva Jack Harrington Sara Wilkinson Kelly Pratt Michael P. Schwarz 《Journal of Insect Behavior》2017,30(1):130-137
Obligate social parasites of Hymenoptera, known as inquilines, have received enormous attention due to the elaborate adaptations they exhibit for exploiting their hosts, and because they have frequently been used to infer sympatric speciation. Their population biology can be difficult to infer as they are both rare and difficult to extract from host nests. Sex allocation has been studied for very few inquilines of social Hymenoptera. Here we report sex ratio patterns in the allodapine bee Inquilina schwarzi, which is an obligate social parasite of another allodapine, Exoneura robusta. We show that the sex ratio of this inquiline varies with its brood number, it is female-biased in the smallest broods, but becomes more even in larger broods, where the population-wide sex ratio is close to parity. We argue that this pattern of bias is consistent with local resource competition, where inquiline females compete to inherit their natal colony. We also argue that extremely female-biased sex ratios of the host species, combined with overall sex ratio parity in the parasite, may help ameliorate disparity in effective population sizes between these two species which are locked in an evolutionary arms race. 相似文献
160.