83 research outputs found
Dissipation and carryover of imidazolinone herbicides in imidazolinone-resistant rice (Oryza sativa)
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file (viewed on October 26, 2007)Vita.Includes bibliographical references.Thesis (M.S.) University of Missouri-Columbia 2007.Dissertations, Academic -- University of Missouri--Columbia -- Agronomy.The development of Imidazolinone (IMI) Resistant (IR) rice now allows rice producers to selectively control red rice (Oryza sativa, O. rufipogon, and O.nivara), weedy relatives of commercial rice (O. sativa). Imazethapyr the primary herbicide used with this technology has been shown to be relatively persistent in the soil and may cause injury to rotational crops including non-IR rice. Imazamox has less soil persistence in non-flooded environments; however, this herbicide has not been studied in rice environments including flooded soils. Thirteen selected treatments of two and three sequential applications of imazethapyr and imazamox were applied to IR rice in 2004 and 2005. In 2005 and 2006, non-IR rice was planted into the previous years' plots to evaluate herbicide carryover. Studies were conducted on two soils commonly utilized for rice production: a DeWitt silt loam and a Sharkey clay soil. Treatments included several variations including common programs with imazamox added, double-rate treatments, and imazamox-only treatments and treatments where imazamox was substituted for imazethapyr. Non-IR rice was evaluated for carryover injury at preflood and 2-week postflood timings. No injury was observed on the silt loam soil in 2005 or on the clay soil in 2006. The addition of imazamox at the preflood in 2005 on the clay soil to any treatment was the main factor increasing injury to significant levels. In 2006 on the silt loam soil, doubling the imazethapyr rate was the main factor increasing injury. However, in all cases, injury was low and in some instances treatments that caused or did not cause injury did not correlate to the herbicide rates applied. To further investigate imidazolinone dissipation, imazethapyr, imazamox and imazapyr were applied to flooded and non-flooded plots on silt loam and clay soils. Soil damples were taken periodically during the year following application. Samples were frozen to stop dissipation. Soil samples were tested using a bioassay and standard curve. From this information, dissipation rates and half lives were estimated. Visual injury was found to provide the best measurement of herbicide quantity in the soil. Half lives for imazamox were found to be 16 d on flooded silt loam, 8 d on flooded clay. Half lives were longer under non-flooded conditions with half lives of 270 and 13 d being calculated on silt loam and clay soils. Imazethapyr half lives ranged from 5 d on flooded clay to 128 d on nonflooded loam. Half lives calculated for imazapyr ranged from 8 to 78 d under flooded and non-flooded conditions on the clay soil, and from 50 to 539 d on the silt loam soil. The active herbicide concentrations declined more quickly under flooded conditions as compared to non-flooded conditions, regardless of soil type. However, dissipation occurred faster on the clay soil as compared to the silt loam
Common activation of canonical Wnt signaling in pancreatic adenocarcinoma.
Pancreatic ductal adenocarcinoma (PDA) is an extremely aggressive malignancy, which carries a dismal prognosis. Activating mutations of the Kras gene are common to the vast majority of human PDA. In addition, recent studies have demonstrated that embryonic signaling pathway such as Hedgehog and Notch are inappropriately upregulated in this disease. The role of another embryonic signaling pathway, namely the canonical Wnt cascade, is still controversial. Here, we use gene array analysis as a platform to demonstrate general activation of the canonical arm of the Wnt pathway in human PDA. Furthermore, we provide evidence for Wnt activation in mouse models of pancreatic cancer. Our results also indicate that Wnt signaling might be activated downstream of Hedgehog signaling, which is an early event in PDA evolution. Wnt inhibition blocked proliferation and induced apoptosis of cultured adenocarcinoma cells, thereby providing evidence to support the development of novel therapeutical strategies for Wnt inhibition in pancreatic adenocarcinoma
Pest management guide : corn, cotton, grain sorghum, rice, soybean, winter wheat
"2015 Missouri."includes statistics"This guide is intended to provide current recommendations for control of the most problematic weeds, insects and diseases encountered in Missouri corn, soybean and winter wheat cropping systems."--Page 2.Kevin W. Bradley (Extension Weed Scientist, Department of Agronomy), Laura E. Sweets, (Extension Plant Pathologist, Department of Plant Microbiology and Pathology, Commercial Agricultural Program), Wayne C. Bailey (Extension Entomologist, Department of Entomology), Moneen M. Jones (Assistant Research Professor, Fisher Delta Research Center), James W. Heiser (Research Associate - Weed Science, Fisher Delta Research Center)New 1/05, Revised 12/14/3C
Genome co-amplification upregulates a mitotic gene network activity that predicts outcome and response to mitotic protein inhibitors in breast cancer.
BACKGROUND: High mitotic activity is associated with the genesis and progression of many cancers. Small molecule inhibitors of mitotic apparatus proteins are now being developed and evaluated clinically as anticancer agents. With clinical trials of several of these experimental compounds underway, it is important to understand the molecular mechanisms that determine high mitotic activity, identify tumor subtypes that carry molecular aberrations that confer high mitotic activity, and to develop molecular markers that distinguish which tumors will be most responsive to mitotic apparatus inhibitors. METHODS: We identified a coordinately regulated mitotic apparatus network by analyzing gene expression profiles for 53 malignant and non-malignant human breast cancer cell lines and two separate primary breast tumor datasets. We defined the mitotic network activity index (MNAI) as the sum of the transcriptional levels of the 54 coordinately regulated mitotic apparatus genes. The effect of those genes on cell growth was evaluated by small interfering RNA (siRNA). RESULTS: High MNAI was enriched in basal-like breast tumors and was associated with reduced survival duration and preferential sensitivity to inhibitors of the mitotic apparatus proteins, polo-like kinase, centromere associated protein E and aurora kinase designated GSK462364, GSK923295 and GSK1070916, respectively. Co-amplification of regions of chromosomes 8q24, 10p15-p12, 12p13, and 17q24-q25 was associated with the transcriptional upregulation of this network of 54 mitotic apparatus genes, and we identify transcription factors that localize to these regions and putatively regulate mitotic activity. Knockdown of the mitotic network by siRNA identified 22 genes that might be considered as additional therapeutic targets for this clinically relevant patient subgroup. CONCLUSIONS: We define a molecular signature which may guide therapeutic approaches for tumors with high mitotic network activity
Plasma Magnetohydrodynamics and Energy Conversion
Contains research objectives and reports on four research projects.U.S. Air Force (Aeronautical Systems Division) under Contract AF33(616)-7624 with the Aeronautical Accessories Laboratory, Wright-Patterson Air Force Base, OhioNational Science Foundation under Grant G-24073National Institutes of Health (Grant HTS-5550
Modeling precision treatment of breast cancer
Background: First-generation molecular profiles for human breast cancers have enabled the identification of features that can predict therapeutic response; however, little is known about how the various data types can best be combined to yield optimal predictors. Collections of breast cancer cell lines mirror many aspects of breast cancer molecular pathobiology, and measurements of their omic and biological therapeutic responses are well-suited for development of strategies to identify the most predictive molecular feature sets. Results: We used least squares-support vector machines and random forest algorithms to identify molecular features associated with responses of a collection of 70 breast cancer cell lines to 90 experimental or approved therapeutic agents. The datasets analyzed included measurements of copy number aberrations, mutations, gene and isoform expression, promoter methylation and protein expression. Transcriptional subtype contributed strongly to response predictors for 25% of compounds, and adding other molecular data types improved prediction for 65%. No single molecular dataset consistently out-performed the others, suggesting that therapeutic response is mediated at multiple levels in the genome. Response predictors were developed and applied to TCGA data, and were found to be present in subsets of those patient samples. Conclusions: These results suggest that matching patients to treatments based on transcriptional subtype will improve response rates, and inclusion of additional features from other profiling data types may provide additional benefit. Further, we suggest a systems biology strategy for guiding clinical trials so that patient cohorts most likely to respond to new therapies may be more efficiently identified
Langerhans-type and monocyte-derived human dendritic cells have different susceptibilities to mRNA electroporation with distinct effects on maturation and activation: implications for immunogenicity in dendritic cell-based immunotherapy
The use of gamma-irradiation and ultraviolet-irradiation in the preparation of human melanoma cells for use in autologous whole-cell vaccines
<p>Abstract</p> <p>Background</p> <p>Human cancer vaccines incorporating autologous tumor cells carry a risk of implantation and subsequent metastasis of viable tumor cells into the patient who is being treated. Despite the fact that the melanoma cell preparations used in a recent vaccine trial (Mel37) were gamma-irradiated (200 Gy), approximately 25% of the preparations failed quality control release criteria which required that the irradiated cells incorporate <sup>3</sup>H-thymidine at no more than 5% the level seen in the non-irradiated cells. We have, therefore, investigated ultraviolet (UV)-irradiation as a possible adjunct to, or replacement for gamma-irradiation.</p> <p>Methods</p> <p>Melanoma cells were gamma- and/or UV-irradiated. <sup>3</sup>H-thymidine uptake was used to assess proliferation of the treated and untreated cells. Caspase-3 activity and DNA fragmentation were measured as indicators of apoptosis. Immunohistochemistry and Western blot analysis was used to assess antigen expression.</p> <p>Results</p> <p>UV-irradiation, either alone or in combination with gamma-irradiation, proved to be extremely effective in controlling the proliferation of melanoma cells. In contrast to gamma-irradiation, UV-irradiation was also capable of inducing significant levels of apoptosis. UV-irradiation, but not gamma-irradiation, was associated with the loss of tyrosinase expression. Neither form of radiation affected the expression of gp100, MART-1/MelanA, or S100.</p> <p>Conclusion</p> <p>These results indicate that UV-irradiation may increase the safety of autologous melanoma vaccines, although it may do so at the expense of altering the antigenic profile of the irradiated tumor cells.</p
The genome of the emerging barley pathogen Ramularia collo-cygni
Background
Ramularia collo-cygni is a newly important, foliar fungal pathogen of barley that causes the disease Ramularia leaf spot. The fungus exhibits a prolonged endophytic growth stage before switching life habit to become an aggressive, necrotrophic pathogen that causes significant losses to green leaf area and hence grain yield and quality.
Results
The R. collo-cygni genome was sequenced using a combination of Illumina and Roche 454 technologies. The draft assembly of 30.3 Mb contained 11,617 predicted gene models. Our phylogenomic analysis confirmed the classification of this ascomycete fungus within the family Mycosphaerellaceae, order Capnodiales of the class Dothideomycetes. A predicted secretome comprising 1053 proteins included redox-related enzymes and carbohydrate-modifying enzymes and proteases. The relative paucity of plant cell wall degrading enzyme genes may be associated with the stealth pathogenesis characteristic of plant pathogens from the Mycosphaerellaceae. A large number of genes associated with secondary metabolite production, including homologs of toxin biosynthesis genes found in other Dothideomycete plant pathogens, were identified.
Conclusions
The genome sequence of R. collo-cygni provides a framework for understanding the genetic basis of pathogenesis in this important emerging pathogen. The reduced complement of carbohydrate-degrading enzyme genes is likely to reflect a strategy to avoid detection by host defences during its prolonged asymptomatic growth. Of particular interest will be the analysis of R. collo-cygni gene expression during interactions with the host barley, to understand what triggers this fungus to switch from being a benign endophyte to an aggressive necrotroph
- …