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991.
Zachary R. King Silas P. Childs Donna K. Harris Kerry F. Pedley James W. Buck H. Roger Boerma Zenglu Li 《Molecular breeding : new strategies in plant improvement》2017,37(5):62
Phakopsora pachyrhizi is a fungal pathogen and the cause of Asian soybean rust. P. pachyrhizi was first detected in the continental USA in 2004 and has since been a threat to the soybean industry. There are six described loci that harbor resistance to P. pachyrhizi (Rpp) genes. The resistance of PI 423972 was previously shown to be within 5 cM of the Rpp4 locus of PI 459025B, yet had differential reactions when challenged with P. pachyrhizi isolates India 1973 and Taiwan 1972. In this study, the resistance of PI 423972 was mapped to a 187.5 kb interval between the SNP markers GSM0543 and GSM0387 on chromosome 18 (51,397,064 to 51,584,617 bp, Glyma.Wm82.a2) that overlaps the interval for Rpp4 and is designated as Rpp4-b. A unique haplotype is described for PI 423972 that separates it from PI 459025B, 32 North American soybean ancestors, and all described sources of Rpp gene resistance. 相似文献
992.
993.
Abiotic influences on bicarbonate use in the giant kelp,Macrocystis pyrifera,in the Monterey Bay
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In the Monterey Bay region of central California, the giant kelp Macrocystis pyrifera experiences broad fluctuations in wave forces, temperature, light availability, nutrient availability, and seawater carbonate chemistry, all of which may impact their productivity. In particular, current velocities and light intensity may strongly regulate the supply and demand of inorganic carbon (Ci) as substrates for photosynthesis. Macrocystis pyrifera can acquire and utilize both CO2 and bicarbonate (HCO3?) as Ci substrates for photosynthesis and growth. Given the variability in carbon delivery (due to current velocities and varying [DIC]) and demand (in the form of saturating irradiance), we hypothesized that the proportion of CO2 and bicarbonate utilized is not constant for M. pyrifera, but a variable function of their fluctuating environment. We further hypothesized that populations acclimated to different wave exposure and irradiance habitats would display different patterns of bicarbonate uptake. To test these hypotheses, we carried out oxygen evolution trials in the laboratory to measure the proportion of bicarbonate utilized by M. pyrifera via external CA under an orthogonal cross of velocity, irradiance, and acclimation treatments. Our Monterey Bay populations of M. pyrifera exhibited proportionally higher external bicarbonate utilization in high irradiance and high flow velocity conditions than in sub‐saturating irradiance or low flow velocity conditions. However, there was no significant difference in proportional bicarbonate use between deep blades and canopy blades, nor between individuals from wave‐exposed versus wave‐protected sites. This study contributes a new field‐oriented perspective on the abiotic controls of carbon utilization physiology in macroalgae. 相似文献
994.
Ward TJ Clear RM Rooney AP O'Donnell K Gaba D Patrick S Starkey DE Gilbert J Geiser DM Nowicki TW 《Fungal genetics and biology : FG & B》2008,45(4):473-484
Analysis of Fusarium head blight (FHB) pathogen diversity revealed that 3ADON producing Fusarium graminearum are prevalent in North America and identified significant population structure associated with trichothecene chemotype differences (F(ST)>0.285; P<0.001). In addition, we identified a trichothecene chemotype cline in Canada and documented a recent and significant shift in FHB pathogen composition by demonstrating that the 3ADON chemotype frequency in western Canada increased more than 14-fold between 1998 and 2004. On average, isolates from 3ADON populations produced significantly (P<0.05) more trichothecene and had significantly (P<0.005) higher fecundity and growth rates than isolates from the 15ADON population. These results indicate that selection is driving the rapid spread of an introduced pathogen population that is more toxigenic and potentially more vigorous. The discovery of this previously unrecognized pathogen diversity has significant implications for food safety and cereal production in North America. 相似文献
995.
Green NK Morrison J Hale S Briggs SS Stevenson M Subr V Ulbrich K Chandler L Mautner V Seymour LW Fisher KD 《The journal of gene medicine》2008,10(3):280-289
BACKGROUND: Transductional targeting of adenovirus following systemic or regional delivery remains one of the most difficult challenges for cancer gene medicine. The numerical excess and anatomical advantage of normal (non-cancer) cells in vivo demand far greater detargeting than is necessary for studies using single cell populations in vitro, and this must be coupled with efficient retargeting to cancer cells. METHODS: Adenovirus (Ad5) particles were coated with reactive poly[N-(2-hydroxypropyl)methacrylamide] copolymers, to achieve detargeting, and retargeting ligands were attached to the coating. Receptor-mediated infection was characterised in vitro and anticancer efficacy was studied in vivo. RESULTS: Polymer coating prevented the virus binding any cellular receptors and mediated complete detargeting in vitro and in vivo. These fully detargeted vectors were efficiently retargeted with the model ligand FGF2 to infect FGFR-positive cells. Specific transduction activity was the same as parental virus, and intracellular routing appeared unaffected. Levels of transduction were up to 100-fold greater than parental virus on CAR negative cells. This level of specificity permitted good efficacy in intraperitoneal cancer virotherapy, simultaneously decreasing peritoneal adhesions seen with parental virus. Following intravenous delivery FGF2 mediated unexpected binding to erythrocytes, improving circulation kinetics, but preventing the targeted virus from leaving the blood stream. CONCLUSIONS: Polymer cloaking enables complete adenovirus detargeting, providing a versatile platform for receptor-specific retargeting. This approach can efficiently retarget cancer virotherapy in vivo. Ligands should be selected carefully, as non-specific interactions with non-target cells (e.g. blood cells) can deplete the pool of therapeutic virus available for targeting disseminated disease. 相似文献
996.
Developing strategies for detection of gene doping 总被引:1,自引:0,他引:1
997.
Characterization and expression of Peroxiredoxin 1 in the neonatal tammar wallaby (Macropus eugenii)
Daly KA Lefévre C Nicholas K Deane E Williamson P 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2008,149(1):108-119
Peroxiredoxin 1 (PRDX1) is a ubiquitously expressed antioxidant with vital roles in basal metabolic functions. In addition PRDX1 is involved in cell differentiation and proliferation, apoptosis and innate immunity. In this study, we have characterized PRDX1 from the tammar wallaby (Macropus eugenii). Tammar PRDX1 has high conservation of functional residues and motifs, and demonstrates a close homology with eutherian and vertebrate orthologues. Stimulation of adult tammar leukocytes with lipopolysaccharide and lipoteichoic acid suggests a role for PRDX1 in innate immune defences. PRDX1 expression in the organs of tammar pouch young was mildly elevated early in life possibly reflecting its role in basal metabolic processes. Later increases in PRDX1 expression correlated with functional maturation of several immune organs or with preparation for increased oxidative stress of emergence. The findings of the study are reflections of the complex integrated roles that PRDX1 has in regulation of oxidative stress, apoptosis, cell differentiation and proliferation, and innate immunity. 相似文献
998.
Anderson SJ Stone CL Posada-Buitrago ML Boore JL Neelam BA Stephens RM Luster DG Frederick RD Pedley KF 《Molecular ecology resources》2008,8(6):1310-1312
Twenty-four simple sequence repeat markers were developed for Phakopsora pachyrhizi, a fungal pathogen of soybean (Glycine max) and other legumes. All 24 of the loci were evaluated on 28 isolates of P. pachyrhizi. Twenty-one loci were polymorphic, with allelic diversity ranging from two to eight alleles, and null alleles were observed for eight of the 24 loci. A preliminary screen with the closely related species, P. meibomiae, indicated that these primer pairs are specific to P. pachyrhizi. 相似文献
999.
Dwan K Altman DG Arnaiz JA Bloom J Chan AW Cronin E Decullier E Easterbrook PJ Von Elm E Gamble C Ghersi D Ioannidis JP Simes J Williamson PR 《PloS one》2008,3(8):e3081
Background
The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a randomised controlled trial. Study publication bias has been recognised as a potential threat to the validity of meta-analysis and can make the readily available evidence unreliable for decision making. Until recently, outcome reporting bias has received less attention.Methodology/Principal Findings
We review and summarise the evidence from a series of cohort studies that have assessed study publication bias and outcome reporting bias in randomised controlled trials. Sixteen studies were eligible of which only two followed the cohort all the way through from protocol approval to information regarding publication of outcomes. Eleven of the studies investigated study publication bias and five investigated outcome reporting bias. Three studies have found that statistically significant outcomes had a higher odds of being fully reported compared to non-significant outcomes (range of odds ratios: 2.2 to 4.7). In comparing trial publications to protocols, we found that 40–62% of studies had at least one primary outcome that was changed, introduced, or omitted. We decided not to undertake meta-analysis due to the differences between studies.Conclusions
Recent work provides direct empirical evidence for the existence of study publication bias and outcome reporting bias. There is strong evidence of an association between significant results and publication; studies that report positive or significant results are more likely to be published and outcomes that are statistically significant have higher odds of being fully reported. Publications have been found to be inconsistent with their protocols. Researchers need to be aware of the problems of both types of bias and efforts should be concentrated on improving the reporting of trials. 相似文献1000.
Cancer cells migrating within a 3D microenvironment are able to adopt either a mesenchymal or amoeboid mode of migration. Amoeboid migration is characterised by membrane blebbing that is dependent on the Rho effectors, ROCK1/2. We identify LIMK2 as the preferred substrate for ROCK1 but find that LIMK2 did not induce membrane blebbing, suggesting that a LIMK2 pathway is not involved in amoeboid-mode migration. In support of this hypothesis, novel FRET data demonstrate a direct interaction between ROCK1 and LIMK2 in polarised but not blebbing cells. Our results point to a specific role for the ROCK1:LIMK2 pathway in mesenchymal-mode migration. 相似文献