Publications by authors named "JE Stewart"

Phenological responses to climate change vary across trophic levels. However, how trophic phenological synchrony determines species' distributions through its effects on population dynamics has rarely been addressed. Here, we show that phenological variation underlies population and geographical range dynamics in a range-shifting herbivore, and demonstrate its interplay with changing trophic interactions.

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  • Neuroblastoma (NB) is a highly dangerous pediatric cancer, and current treatments for high-risk patients are not very effective, prompting research into new therapies.
  • Two new PP2A activators, ATUX-3364 and ATUX-8385, were tested in various NB cell lines and in animal models, revealing that they can activate PP2A and significantly reduce cancer cell viability, growth, and movement.
  • The study found that these activators not only hinder tumor growth in live models but also impact MYCN protein levels, suggesting potential for developing targeted therapies against MYCN in treating neuroblastoma.
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  • Diplodia shoot blight and canker disease (DSB) is caused by the fungal pathogen Diplodia sapinea and primarily affects 2-3 needled pines, such as ponderosa pine, resulting in various symptoms including necrotic needles, cankers, and dieback.
  • The pathogen can exist without visible symptoms in trees, making it difficult to detect, and outbreaks are more common in stressed environments like nurseries and seed orchards.
  • Although D. sapinea has not been previously reported in Colorado, studies confirmed its presence and pathogenicity after observing symptoms in ponderosa pines in Wyoming in 2018 and discovering symptomatic trees in Colorado in 2021.
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Unlabelled: Fires in coniferous forests throughout the northern United States alter ecosystem processes and ecological communities, including the diversity and composition of microbial communities living in the soil. In addition to its influence on ecosystem processes and functions, the soil microbiome can interact with soilborne pathogens to facilitate or suppress plant disease development. Altering the microbiome composition to promote taxa that inhibit pathogenic activity has been suggested as a management strategy for forest diseases, including Armillaria root disease caused by , which causes growth loss and mortality of conifers.

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Leptomeningeal dissemination (LMD) is the primary cause of treatment failure in children with group 3 medulloblastoma (MB). Building on our previous work on protein phosphatase 2A (PP2A) activation in MB, here we present preclinical and molecular data on the effects of two novel classes of PP2A activators on disease processes of LMD in group 3 MB. The PP2A activators used in this study are ATUX-6156 and ATUX-6954 (diarylmethylcycloamine sulfonylureas), and ATUX-1215 and ATUX-5800 (diarylmethyl-4-aminotetrahydropyran-sulfonamides).

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Here, we describe patterns of reproduction and flight phenology of putative Phloeosinus punctatus in giant sequoia groves and compare morphology and genotypes of beetles from sympatric giant sequoia (Sequoiadendron giganteum) and California incense-cedar (Calocedrus decurrens). Surveys conducted in 2022 revealed that numerous branches fall from giant sequoia crowns (on average ~30 branches/tree), with 20%-50% of trees per site shedding branches, depositing breeding material for beetles on the forest floor that subsequently becomes colonized. When noninfested branches cut from mature giant sequoias were placed at the ground surface, they were colonized by P.

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Background: Neuroblastoma is the most common extracranial solid tumor in children and accounts for 15% of pediatric cancer related deaths. Targeting neuroblastoma with immunotherapies has proven challenging due to a paucity of immune cells in the tumor microenvironment and the release of immunosuppressive cytokines by neuroblastoma tumor cells. We hypothesized that combining an oncolytic Herpes Simplex Virus (oHSV) with natural killer (NK) cells might overcome these barriers and incite tumor cell death.

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Introduction: Soil-borne pathogens cause considerable crop losses and food insecurity in smallholder systems of sub-Saharan Africa. Soil and crop testing is critical for estimating pathogen inoculum levels and potential for disease development, understanding pathogen interactions with soil nutrient and water limitations, as well as for developing informed soil health and disease management decisions. However, formal laboratory analyses and diagnostic services for pathogens are often out of reach for smallholder farmers due to the high cost of testing and a lack of local laboratories.

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  • The study investigated how different storage temperatures (0.5, 3, and 10 °C) affect the quality and health of hardy kiwifruit, focusing on symptoms of chilling injury and physiological disorders.
  • The lowest temperature (0.5 °C) caused the highest levels of peel pitting and elevated proline and branched-chain amino acids, indicating stress responses, while the highest temperature (10 °C) led to increased fruit shriveling and decay after 5 weeks.
  • Proper temperature management is essential for maintaining fruit quality and minimizing disorders during cold storage of 'Autumn Sense' kiwifruit.
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Background: Pediatric gastroenteropancreatic neuroendocrine tumors are exceedingly rare, resulting in most pediatric treatment recommendations being based on data derived from adults. Trametinib is a kinase inhibitor that targets MEK1/2 and has been employed in the treatment of cancers harboring mutations in the Ras pathway.

Methods: We utilized an established human pediatric gastroenteropancreatic neuroendocrine-like tumor patient-derived xenograft (PDX) with a known NRAS mutation to study the effects of MEK inhibition.

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Brown root rot disease (BRRD) is a highly destructive tree disease. Early diagnosis of BRRD has been challenging because the first symptoms and signs are often observed after extensive tissue colonization. Existing molecular detection methods, all based on the internal transcribed spacer (ITS) region, were developed without testing against global isolates, other wood-decay fungi, or host plant tissues.

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Background: Chemoresistance contributes to relapse in high-risk neuroblastoma. Cancer cells acquire resistance through multiple mechanisms, including drug efflux pumps. In neuroblastoma, multidrug resistance-associated protein-1 (MRP1/ABCC1) efflux pump expression correlates with worse outcomes.

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The Neonatal Intensive Care Unit (NICU) has a language and culture that is its own. For professionals, it is a place of intense and constant attention to microdetails and cautious optimism. For parents, it is a foreign place with a new and unique language and culture.

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Cardiac mitochondrial dysfunction is a critical contributor to the pathogenesis of aging and many age-related conditions. As such, complete control of mitochondrial function is critical to maintain cardiac efficiency in the aged heart. Lysine acetylation is a reversible post-translational modification shown to regulate several mitochondrial metabolic and biochemical processes.

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  • Interspecific hybridization can lead to new fungal pathogens, particularly when involving native and invasive species, with potential negative effects on ecosystems.
  • The study focused on the hybrid Cronartium x flexili between the invasive Cronartium ribicola and native Cronartium comandrae, collecting samples from different tree species across multiple sites.
  • Findings indicate that hybridization is occurring, with distinct genotypes found in specific areas, and while low in frequency, this hybrid has the potential to spread and impact forest health significantly.
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is a native fungal pathogen in western North America that causes black stain root disease (BSRD) of conifers. Three host-specialized varieties of this pathogen were previously described: var. on pinyon pines ( and .

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Hepatoblastoma is the most common primary pediatric liver tumor. Children with pulmonary metastases at diagnosis experience survival rates as low as 25%. We have shown PIM kinases play a role in hepatoblastoma tumorigenesis.

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is a foliar pathogen to conifer tree species. In this study, we conducted whole-genome and transcriptome analyses on isolates of collected from symptomatic Leyland cypress leaves from a Christmas tree farm in Mississippi. The objectives for this research were to elucidate the pathogenicity mechanisms of by characterizing the genome and transcriptome and possibly identify unique and shared predicted genes in comparison with non-conifer/canker and foliar pathogens in the family .

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Background: Sarcomas are a heterogenous collection of bone and soft tissue tumors. The heterogeneity of these tumors makes it difficult to standardize treatment. CDK 4/6 inhibitors are a family of targeted agents which limit cell cycle progression and have been shown to be upregulated in sarcomas.

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Understanding processes leading to disease emergence is important for effective disease management and prevention of future epidemics. Utilizing whole genome sequencing, we studied the phylogenetic relationship and diversity of two populations of the bacterial oak pathogen Lonsdalea quercina from western North America (Colorado and California) and compared these populations to other Lonsdalea species found worldwide. Phylogenetic analysis separated Colorado and California populations into two Lonsdalea clades, with genetic divergence near species boundaries, suggesting long isolation and populations that differ in genetic structure and distribution and possibly their polyphyletic origin.

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Understanding the host-pathogen-environmental interactions in a pathosystem is essential for management of diseases and diminished crop yields. Abiotic stressors such as cold damage, water deficit, and high pH soils can be major limiting factors to tree fruit production. Along with decreased yields, these abiotic factors can have direct implications for disease severity within orchards.

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The use of three-dimensional (3D) bioprinting has remained at the forefront of tissue engineering and has recently been employed for generating bioprinted solid tumors to be used as cancer models to test therapeutics. In pediatrics, neural crest-derived tumors are the most common type of extracranial solid tumors. There are only a few tumor-specific therapies that directly target these tumors, and the lack of new therapies remains detrimental to improving the outcomes for these patients.

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Objective: Two main fungal leaf spot diseases occur in peanut, namely early leaf spot (ELS) and late leaf spot (LLS), these cause a yearly average of $44 million losses. Limited genetic information, 3534 bp of sequencing, exists about the causal agent of LLS, Cercosporidium personatum (syn. Nothopassalora personata, syn.

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Background: The tumor suppressor, protein phosphatase 2A (PP2A), is downregulated in hepatoblastoma. We aimed to examine the effects of two novel compounds of the tricyclic sulfonamide class, ATUX-3364 (3364) and ATUX-8385 (8385), designed to activate PP2A without causing immunosuppression, on human hepatoblastoma.

Methods: An established human hepatoblastoma cell line, HuH6, and a human hepatoblastoma patient-derived xenograft, COA67, were treated with increasing doses of 3364 or 8385, and viability, proliferation, cell cycle and motility were investigated.

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