Publications by authors named "Blewett T"

Elasmobranchs are commonly carnivores and are important in energy transfer across marine ecosystems. Despite this, relatively few studies have examined the physiological underpinnings of nutrient acquisition in these animals. Here, we investigated the mechanisms of uptake at the spiral valve intestine for two representative amino acids (-alanine, -leucine) and one representative fatty acid (oleic acid), each common to the diet of a carnivore, the Pacific spiny dogfish (Squalus suckleyi).

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Background: Minimally invasive molecular profiling using cell-free DNA (cfDNA) is increasingly important to the management of cancer patients; however, low sensitivity remains a major limitation, particularly for brain tumor patients. Transiently attenuating cfDNA clearance from the body-thereby, allowing more cfDNA to be sampled-has been proposed to improve the performance of liquid biopsy diagnostics. However, there is a paucity of clinical data on the effect of higher cfDNA recovery.

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Many species exhibit social living which offers ecological advantages such as increased foraging opportunities, more efficient locomotion and reduced predation risk. Additionally, exposure to multiple individuals of the same species can decrease an individual's stress and metabolic demand, termed social buffering. If disruption to an animal's social structure occurs and prevents social buffering, an elevated metabolic rate and thus ventilation frequency and gill permeability are likely.

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Anthropogenic pollutants are near-ubiquitous in aquatic systems. Aquatic animals such as fishes are subject to physiological stress induced by pollution present in aquatic systems, which can translate to changes in behaviour. Key adaptive behaviours such as shoaling and schooling may be subject to change as a result of physiological or metabolic stress or neurosensory impacts of pollution.

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Organic ultraviolet filters (UVFs) are known to contaminate many aquatic ecosystems, with much environmental contamination attributed to the use of UVF-containing skin care products such as sunscreens during aquatic recreation. Most studies addressing the impact of sunscreen contamination have focused on the effects of UVFs under the assumption that they are the primary contaminants of concern from sunscreen pollution; however, the extent to which the toxicity of UVFs is representative of the environmental impacts of the whole sunscreen mixture is unknown. To address this knowledge gap, this study compared the mixture toxicity of five off-the-shelf sunscreen spray products containing the UVFs avobenzone, homosalate, octisalate, octocrylene and oxybenzone to the toxicity of each UVF in isolation to the freshwater invertebrate Daphnia magna.

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Anthropogenically induced changes to the natural world are increasingly exposing organisms to stimuli and stress beyond that to which they are adapted. In aquatic systems, it is thought that certain life stages are more vulnerable than others, with embryos being flagged as highly susceptible to environmental stressors. Interestingly, evidence from across a wide range of taxa suggests that aquatic embryos can hatch prematurely, potentially as an adaptive response to external stressors, despite the potential for individual costs linked with underdeveloped behavioural and/or physiological functions.

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Lettuce has been commonly associated with the contamination of human pathogens, such as Escherichia coli O157:H7 (hereafter O157:H7), which has resulted in serious foodborne illnesses. Contamination events may happen throughout the farm-to-fork chain, when O157:H7 colonizes edible tissues and closely interacts with the plant. Environmental conditions have a significant impact on many plant-microbe interactions; however, it is currently unknown whether temperature affects O157:H7 colonization of the lettuce phyllosphere.

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The freshwater sponge, Ephydatia muelleri, lacks a nervous or endocrine system and yet it exhibits a coordinated whole-body action known as a "sneeze" that can be triggered by exposure to L-glutamate. It is not known how L-glutamate is obtained by E. muelleri in sufficient quantities (i.

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Liquid biopsies enable early detection and monitoring of diseases such as cancer, but their sensitivity remains limited by the scarcity of analytes such as cell-free DNA (cfDNA) in blood. Improvements to sensitivity have primarily relied on enhancing sequencing technology ex vivo. We sought to transiently augment the level of circulating tumor DNA (ctDNA) in a blood draw by attenuating its clearance in vivo.

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Background: Tracing patient-specific tumor mutations in cell-free DNA (cfDNA) for minimal residual disease (MRD) detection is promising but challenging. Assaying more mutations and cfDNA stands to improve MRD detection but requires highly accurate, efficient sequencing methods and proper calibration to prevent false detection with bespoke tests.

Methods: MAESTRO (Minor Allele Enriched Sequencing Through Recognition Oligonucleotides) uses mutation-specific oligonucleotide probes to enrich cfDNA libraries for tumor mutations and enable their accurate detection with minimal sequencing.

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There is an emerging call from scientists globally to advance the environmental relevance of laboratory studies, particularly within the field of ecotoxicology. To answer this call, we must carefully examine and elucidate the shortcomings of standardized toxicity testing methods that are used in the derivation of toxicity values and regulatory criteria. As a consequence of rapidly accelerating climate change, the inclusion of abiotic co-stressors are increasingly being incorporated into toxicity studies, with the goal of improving the representativeness of laboratory-derived toxicity values used in ecological risk assessments.

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Dissolved organic matter is a ubiquitous component of freshwater and marine environments, and includes small nutrient molecules, such as amino acids, which may be available for uptake by aquatic biota. Epithelial transporters, including cotransporters, uniporters and antiporters, facilitate the absorption of dissolved amino acids (often against concentration gradients). Although there is a lack of mechanistic and molecular characterization of such transporters, pathways for the direct uptake of amino acids from the water appear to exist in a wide range of marine phyla, including Porifera, Cnidaria, Platyhelminthes, Brachiopoda, Mollusca, Nemertea, Annelida, Echinodermata, Arthropoda and Chordata.

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Hydraulic fracturing for oil and gas extraction produces large volumes of wastewater, termed flowback and produced water (FPW), that are highly saline and contain a variety of organic and inorganic contaminants. In the present study, FPW samples from ten hydraulically fractured wells, across two geologic formations were collected at various timepoints. Samples were analyzed to determine spatial and temporal variation in their inorganic composition.

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Temperate freshwater fishes can experience large seasonal temperature fluctuations that could affect their exposure and sensitivity to trace metals. Yet, temperature effects are overlooked in ecotoxicology studies, especially for cold temperatures typical of the winter. In the present study, the effects of long-term cold acclimation on Cd bioaccumulation and toxicity were investigated in a freshwater fish, the banded killifish (Fundulus diaphanus).

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Background: We aimed to examine circulating tumor DNA (ctDNA) and its association with residual cancer burden (RCB) using an ultrasensitive assay in patients with triple-negative breast cancer (TNBC) receiving neoadjuvant chemotherapy.

Patients And Methods: We identified responders (RCB 0/1) and matched non-responders (RCB 2/3) from the phase II TBCRC 030 prospective study of neoadjuvant paclitaxel versus cisplatin in TNBC. We collected plasma samples at baseline, 3 weeks and 12 weeks (end of therapy).

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Detecting mutations from single DNA molecules is crucial in many fields but challenging. Next-generation sequencing (NGS) affords tremendous throughput but cannot directly sequence double-stranded DNA molecules ('single duplexes') to discern the true mutations on both strands. Here we present Concatenating Original Duplex for Error Correction (CODEC), which confers single duplex resolution to NGS.

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Many aquatic species are well known as extremely successful invaders. The green crab ( is an arthropod native to European waters; however, it is now known to be a globally invasive species. Recently, it was discovered that the could transport nutrients in the form of amino acids across their gill from the surrounding environment, a feat previously thought to be impossible in arthropods.

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Organic ultraviolet filters (UVFs) are contaminants of concern, ubiquitously found in many aquatic environments due to their use in personal care products to protect against ultraviolet radiation. Research regarding the toxicity of UVFs such as avobenzone, octocrylene and oxybenzone indicate that these chemicals may pose a threat to invertebrate species; however, minimal long-term studies have been conducted to determine how these UVFs may affect continuously exposed populations. The present study modeled the effects of a 5-generation exposure of Daphnia magna to these UVFs at environmental concentrations.

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Purpose: To examine circulating tumor DNA (ctDNA) and its association with residual cancer burden (RCB) using an ultrasensitive assay in patients with triple-negative breast cancer (TNBC) receiving neoadjuvant chemotherapy (NAT).

Patients And Methods: We identified responders (RCB-0/1) and matched non-responders (RCB-2/3) from the phase II TBCRC 030 prospective study of neoadjuvant paclitaxel vs. cisplatin in TNBC.

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Intertidal mussels are well adapted to withstand emersion from water during low tide, but they may be intermittently exposed to waterborne toxicants such as copper, which targets physiological processes including metabolism, ammonia excretion, and osmoregulation. To determine if copper exposure damages intertidal organisms' ability to tolerate tidal emersion, Mediterranean mussels (Mytilus galloprovincialis) were exposed to copper for 96 h followed by 6 h of emersion. Oxygen uptake increased after copper exposure which suggests that copper accumulation caused moderate stress in the mussels, but ammonia excretion and anaerobic metabolism were unaffected by mixed copper and emersion exposures.

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Intertidal animals experience cycles of tidal emersion from water and are vulnerable to copper (Cu) exposure due to anthropogenic toxicant input into marine waters. Both emersion and Cu toxicity can cause damage to physiological processes like aerobic metabolism, ammonia excretion, and osmoregulation, but the interactions of the combination of these two stressors on marine invertebrates are understudied. Mixed effects of 96 h of low and high Cu exposure (20 and 200 μg/L) followed by 6 h of tidal emersion were evaluated on the intertidal sea cucumber Cucumaria miniata.

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Hydraulic fracturing extracts oil and gas through the injection of water and proppants into subterranean formations. These injected fluids mix with the host rock formation and return to the surface as a complex wastewater containing salts, metals, and organic compounds, termed flowback and produced water (FPW). Previous research indicates that FPW is toxic to , impairing reproduction, molting, and maturation time; however, recovery from FPW has not been extensively studied.

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Liquid biopsies are enabling minimally invasive monitoring and molecular profiling of diseases across medicine, but their sensitivity remains limited by the scarcity of cell-free DNA (cfDNA) in blood. Here, we report an intravenous priming agent that is given prior to a blood draw to increase the abundance of cfDNA in circulation. Our priming agent consists of nanoparticles that act on the cells responsible for cfDNA clearance to slow down cfDNA uptake.

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Blood-based, or "liquid," biopsies enable minimally invasive diagnostics but have limits on sensitivity due to scarce cell-free DNA (cfDNA). Improvements to sensitivity have primarily relied on enhancing sequencing technology . Here, we sought to augment the level of circulating tumor DNA (ctDNA) detected in a blood draw by attenuating the clearance of cfDNA .

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