Publications by authors named "David Cook"

In patients with pancreatic ductal adenocarcinoma (PDAC), intratumoural and intertumoural heterogeneity increases chemoresistance and mortality rates. However, such morphological and phenotypic diversities are not typically captured by organoid models of PDAC. Here we show that branched organoids embedded in collagen gels can recapitulate the phenotypic landscape seen in murine and human PDAC, that the pronounced molecular and morphological intratumoural and intertumoural heterogeneity of organoids is governed by defined transcriptional programmes (notably, epithelial-to-mesenchymal plasticity), and that different organoid phenotypes represent distinct tumour-cell states with unique biological features in vivo.

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Management of vulnerable amphibian populations requires a better understanding of the habitat factors that will make the greatest difference in their preservation. We set out to develop a predictive model of amphibian abundance based on habitat characteristics that may influence their survival and persistence. Our study system was the Sonoma County California tiger salamander (Ambystoma californiense; SCTS), an amphibian threatened by habitat loss and fragmentation.

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Hop leaves, a by-product from hop cone harvesting, contain phenolic compounds of potential value for food or beverage applications. However, the abundant phenolics in hop leaves remain largely unquantified. This study quantified phenolics in hop leaves over two crop years, for three commercially significant varieties, at different developmental stages post-flowering.

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  • This study examined how the immune responses of Arabidopsis thaliana can be applied to various pathogens using a machine learning approach, focusing on Botrytis cinerea, Sclerotinia sclerotiorum, and Pseudomonas syringae.
  • Researchers used feature selection techniques to train predictive models based on early gene expression data, allowing them to analyze a smaller subset of the transcriptome.
  • The findings suggest that while different gene sets are involved, there are common immune responses to various pathogens, indicating the potential for machine learning to enhance our understanding of plant immunity and improve disease resistance prediction.
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Objective: Little research has inductively investigated the unique nontechnical qualities required of a surgeon holistic to their practice. This is problematic because there may be additional nuances, or entirely new attributes, that can only be identified in the authentic context of surgical practice. The aim of this study was to investigate the unique nontechnical qualities required of surgeons holistic to their practice.

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Cell state dynamics underlying successful tissue regeneration are undercharacterized. In the intestine, damage prompts epithelial reprogramming into revival stem cells (revSCs) that reconstitute Lgr5 intestinal stem cells (ISCs). Here single-nuclear multi-omics of mouse crypts regenerating from irradiation shows revSC chromatin accessibility overlaps with ISCs and differentiated lineages.

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The Drosophila adult midgut progenitor cells (AMPs) give rise to all cells in the adult midgut epithelium, including the intestinal stem cells (ISCs). While they share many characteristics with the ISCs, it remains unclear how they are generated in the early embryo. Here, we show that they arise from a population of endoderm cells, which exhibit multiple similarities with Drosophila neuroblasts.

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BTX-A51, a first-in-class oral small molecule inhibitor of casein kinase 1α (CK1α) and cyclin dependent kinase (CDK) 7 and 9, induces apoptosis of leukemic cells by activating p53 and inhibiting expression of . Here, we report on the results of the phase 1 clinical trial of BTX-A51 in patients with relapsed or refractory AML and MDS. Thirty-one patients were enrolled into 8 dose-escalation cohorts at BTX-A51 doses ranging from 1mg to 42mg dosed three days/week for 21 or 28 days out a 28-day cycle.

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The mechanisms that ensure developmental progression in the early human embryo remain largely unknown. Here, we show that the family of long interspersed nuclear element 1 (LINE1) transposons prevents the reversion of naive human embryonic stem cells (hESCs) to 8-cell-like cells (8CLCs). LINE1 RNA contributes to maintenance of H3K27me3 levels, particularly at chromosome 19 (Chr19).

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A major limitation to producing high seed yields in berseem clover (Trifolium alexandrinum L.) is failure to set seed, predominantly due to lack of pollination. Despite the importance of berseem clover as a leading forage legume, the contribution of pollinators to seed set is scarce.

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High-grade serous ovarian carcinoma (HGSC) remains a disease with poor prognosis that is unresponsive to current immune checkpoint inhibitors. Although PI3K pathway alterations, such as PTEN loss, are common in HGSC, attempts to target this pathway have been unsuccessful. We hypothesized that aberrant PI3K pathway activation may alter the HGSC immune microenvironment and present a targeting opportunity.

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The genomes of the fungus that causes blast diseases on diverse grass species, including major crops, have indispensable core-chromosomes and may contain supernumerary chromosomes, also known as mini-chromosomes. These mini-chromosomes are speculated to provide effector gene mobility, and may transfer between strains. To understand the biology of mini-chromosomes, it is valuable to be able to detect whether a strain possesses a mini-chromosome.

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Purpose: Subtle liver metastases may be missed in contrast enhanced CT imaging. We determined the impact of lesion location and conspicuity on metastasis detection using data from a prior reader study.

Methods: In the prior reader study, 25 radiologists examined 40 CT exams each and circumscribed all suspected hepatic metastases.

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The cardiac conduction system (CCS) is a network of specialized cardiomyocytes that coordinates electrical impulse generation and propagation for synchronized heart contractions. Although the components of the CCS, including the sinoatrial node, atrioventricular node, His bundle, bundle branches, and Purkinje fibers, were anatomically discovered more than 100 years ago, their molecular constituents and regulatory mechanisms remain incompletely understood. Here, we demonstrate the transcriptomic landscape of the postnatal mouse CCS at a single-cell resolution with spatial information.

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The use of the blow fly as a potential pollination species to augment the current reliance on honeybees () in Australian horticulture requires knowledge of how best to mass-rear this fly species. lays eggs onto carrion soon after death, and the resultant larvae that hatch are necrophagous and feed on the decomposing tissues of the dead animal. Newly hatched larvae of this fly were provided with plant-based meals (soya bean and canola) and compared with larvae provided with livestock-derived meatmeal to determine if plant-based meal could be used to mass-rear this blow fly species.

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Background: Binary classification models are frequently used to predict clinical deterioration, however they ignore information on the timing of events. An alternative is to apply time-to-event models, augmenting clinical workflows by ranking patients by predicted risks. This study examines how and why time-to-event modelling of vital signs data can help prioritise deterioration assessments using lift curves, and develops a prediction model to stratify acute care inpatients by risk of clinical deterioration.

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Virtual patients (VPs) have long been used to teach and assess clinical reasoning. VPs can be programmed to simulate authentic patient-clinician interactions and to reflect a variety of contextual permutations. However, their use has historically been limited by the high cost and logistical challenges of large-scale implementation.

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While conventional wisdom initially postulated that PD-L1 serves as the inert ligand for PD-1, an emerging body of literature suggests that PD-L1 has cell-intrinsic functions in immune and cancer cells. In line with these studies, here we show that engagement of PD-L1 via cellular ligands or agonistic antibodies, including those used in the clinic, potently inhibits the type I interferon pathway in cancer cells. Hampered type I interferon responses in PD-L1-expressing cancer cells resulted in enhanced efficacy of oncolytic viruses in vitro and in vivo.

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Introduction: Neurologic circadian influences, including sleep/wake transitions, processes (e.g., hormonal variation), and behavioral patterns (e.

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Clinical outcomes for total-pancreatectomy followed by intraportal islet autotransplantation (TP-IAT) to treat chronic pancreatitis (CP) are suboptimal due to pancreas inflammation, oxidative stress during islet isolation, and harsh engraftment conditions in the liver's vasculature. We describe a thermoresponsive, antioxidant macromolecule poly(polyethylene glycol citrate---isopropylacrylamide) (PPCN) to protect islet redox status and function and to enable extrahepatic omentum islet engraftment. PPCN solution transitions from a liquid to a hydrogel at body temperature.

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  • The study investigates the effectiveness of Electronic Nicotine Delivery Systems (ENDS) in delivering nicotine compared to traditional cigarettes and analyzes the relationship between nicotine concentration and actual nicotine uptake in users.
  • Using meta-analysis of 12 studies on nicotine-salt ENDS, the research examines if the amount of nicotine per puff can predict how much nicotine users actually absorb (C).
  • The findings suggest a strong correlation between nicotine per puff and C across various conditions, and simpler linear models were found to be more effective than complex models in predicting nicotine absorption, highlighting discrepancies between e-liquid nicotine levels and user uptake.
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Purpose: To validate the Motivated Strategies for Learning Questionnaire (MSLQ), which measures learner motivations; and the Instructional Materials Motivation Survey (IMMS), which measures the motivational properties of educational activities.

Methods: Participants (333 pharmacists, physicians, and advanced practice providers) completed the MSLQ, IMMS, Congruence-Personalization Questionnaire (CPQ), and a knowledge test immediately following an online learning module (April 2021). We randomly divided data for split-sample analysis using confirmatory factor analysis (CFA), exploratory factor analysis (EFA), and the multitrait-multimethod matrix.

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  • Mild traumatic brain injury (mTBI), especially from blast exposure, is linked to a higher risk of developing neurodegenerative diseases like Alzheimer's and chronic traumatic encephalopathy, particularly in military personnel.
  • Research showed distinct changes in the expression of AQP4, a protein important for brain fluid dynamics, in the frontal cortex after blast exposure in both humans and a mouse model.
  • Veterans with blast mTBI exhibited MRI-visible changes that suggest disruption of brain fluid clearance, which may contribute to lasting symptoms and long-term brain health issues.
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