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1.
Sci Total Environ ; 942: 173675, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-38839014

RESUMEN

Microphytobenthic (MPB) biofilms play significant roles in the ecology of coastal mudflats, including provision of essential food resources to shorebird species. In these ecosystems, water-divergence structures like jetties and causeways can drastically alter sedimentation patterns and mudflat topography, yet their effects on MPB biofilm biomass and distribution are poorly understood. Here, we used a combination of unoccupied aerial vehicle (UAV) technologies, photogrammetric processing, and sediment field samples to compare biofilm and mudflat characteristics between areas of the Fraser River Estuary with varying sedimentary regimes and shorebird use. Our aims were to: (1) demonstrate the use of fine spatial resolution UAV-acquired multispectral imagery (cm2) with extensive spatial coverage (>km2) and a co-alignment photogrammetric processing techniques to survey MPB biofilm and mudflat topography at spatial scales and detail relevant to foraging shorebirds; and, (2) investigate the effects of water-divergence structures on mudflat elevation and microtopography, as well as MPB biofilm biomass, distribution, and spatial patterning. From a technical perspective, co-alignment allowed us to analyze aligned and continuous fine-resolution elevation models and orthomosaics for large areas of the estuary, while the normalized difference vegetation index was a good predictor of sediment chlorophyll-a (R2 = 0.9). Using these data products, we found that mudflats in close proximity to water-divergence structures have cross-shore profiles characteristic of low sediment supply as well as decreased microtopographic variability. At disturbed sites, elevation and microtopography had a weaker influence on biofilm biomass compared to intact estuarine ecosystem sites. Analysis of biofilm patch showed that sites either had a relatively small number of large, contiguous patches, or a large number of smaller, isolated patches; however, less disturbed sites did not necessarily have larger biofilm patches than more disturbed sites. We conclude that UAV-acquired multispectral imagery and co-alignment-based workflow are promising new tools for ecologists to map, monitor, and understand MPB biofilm dynamics in ecologically sensitive estuaries.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos , Fotogrametría , Sedimentos Geológicos/química , Monitoreo del Ambiente/métodos , Biopelículas , Ecosistema , Animales , Estuarios , Biomasa
2.
J Parasitol ; 110(3): 206-209, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38802105

RESUMEN

Toxoplasma gondii is a zoonotic protozoan parasite that infects most warm-blooded animals, including birds. Scavenging birds are epidemiologically important hosts because they can serve as indicators of environmental T. gondii levels. A rapid point-of-care (POC) test that detects antibodies to T. gondii in humans is commercially available. In this research, we assessed the ability of the human POC test to detect anti-T. gondii antibodies in 106 black vultures (Coragyps atratus) and 23 ring-billed gulls (Larus delawarensis) from Pennsylvania, USA. Serum samples were tested with the POC test and compared to the modified agglutination test (MAT) in a blinded study. Overall, anti-T. gondii antibodies were detected in 2.8% (3/106) of black vultures and 60.9% (14/23) of ring-billed gulls by the POC test. One false-positive POC test occurred in a black vulture that was negative by MAT. False-negative results were obtained in 2 black vultures and 4 ring-billed gulls that had MAT titers of 1:25 or 1:50. The sensitivity and specificity of the POC for both black vultures and ring-billed gulls combined were 95.7% and 95.5%, respectively. This is the first study using human POC tests to detect antibodies to T. gondii in birds. Further study of the rapid test as a screening tool for serological surveillance of T. gondii in birds is warranted.


Asunto(s)
Pruebas de Aglutinación , Anticuerpos Antiprotozoarios , Enfermedades de las Aves , Charadriiformes , Falconiformes , Toxoplasma , Toxoplasmosis Animal , Animales , Anticuerpos Antiprotozoarios/sangre , Toxoplasma/inmunología , Charadriiformes/parasitología , Pennsylvania/epidemiología , Toxoplasmosis Animal/diagnóstico , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/inmunología , Enfermedades de las Aves/parasitología , Enfermedades de las Aves/diagnóstico , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/inmunología , Falconiformes/parasitología , Pruebas de Aglutinación/veterinaria , Sensibilidad y Especificidad , Pruebas en el Punto de Atención
3.
Environ Toxicol Chem ; 43(6): 1442-1457, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38695731

RESUMEN

Microplastic pollution threatens some of the world's most iconic locations for marine biodiversity, including the remote Galápagos Islands, Ecuador. Using the Galápagos penguin (Spheniscus mendiculus) as a sentinel species, the present study assessed microplastics and suspected anthropogenic cellulose concentrations in surface seawater and zooplankton near Santa Cruz and Galápagos penguin colonies (Floreana, Isabela, Santiago), as well as in penguin potential prey (anchovies, mullets, milkfish) and penguin scat. On average, 0.40 ± 0.32 microplastics L-1 were found in surface seawater (<10 µm; n = 63 L), while 0.003, 0.27, and 5.12 microplastics individual-1 were found in zooplankton (n = 3372), anchovies (n = 11), and mullets (n = 6), respectively. The highest concentration (27 microplastics individual-1) was observed in a single milkfish. Calculations based on microplastics per gram of prey, in a potential diet composition scenario, suggest that the Galápagos penguin may consume 2881 to 9602 microplastics daily from prey. Despite this, no microplastics or cellulose were identified in 3.40 g of guano collected from two penguins. Our study confirms microplastic exposure in the pelagic food web and endangered penguin species within the UNESCO World Heritage site Galápagos Islands, which can be used to inform regional and international policies to mitigate plastic pollution and conserve biodiversity in the global ocean. Environ Toxicol Chem 2024;43:1442-1457. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Asunto(s)
Celulosa , Monitoreo del Ambiente , Cadena Alimentaria , Microplásticos , Spheniscidae , Contaminantes Químicos del Agua , Animales , Microplásticos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Ecuador , Zooplancton/efectos de los fármacos , Agua de Mar/química
4.
MethodsX ; 12: 102676, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38617899

RESUMEN

Identifying biogeographic regions through cluster analysis of species distribution data is a common method for partitioning ecosystems. Selecting the appropriate cluster analysis method requires a comparison of multiple algorithms. In this study, we demonstrate a data-driven process to select a method for bioregionalization based on community data and test its robustness to data variability following these steps: •We aggregated and curated zooplankton community observations from expeditions in the Northeast Pacific.•We determined the best bioregionalization approach by comparing nine cluster analysis methods using ten goodness of clustering indices.•We evaluated the robustness of the bioregionalization to different sources of sampling and taxonomic variability by comparing the bioregionalization of the overall dataset with bioregionalizations of subsets of the data. The K-means clustering of the log-chord transformed abundance was selected as the optimal method for bioregionalization of the zooplankton dataset. This clustering resulted in the emergence of four bioregions along the cross-shelf gradient: the Offshore, Deep Shelf, Nearshore, and Deep Fjord bioregions. The robustness analyses demonstrated that the bioregionalization was consistent despite variability in the spatial and temporal frequency of sampling, sampling methodology, and taxonomic coverage.

5.
Oecologia ; 204(1): 227-239, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38219265

RESUMEN

Marine food webs are strongly size-structured and size-based analysis of communities is a useful approach to evaluate food webs in a way that can be compared across systems. Fatty acid analysis is commonly used to identify diet sources of species, offering a powerful complement to stable isotopes, but is rarely applied to size-structured communities. In this study, we used fatty acids and stable isotopes to characterize size-based variation in prey resources and trophic pathways over a nine-month temperate coastal ocean time series of seven plankton size classes, from > 0.7-µm particulate organic matter through > 2000-µm zooplankton. Zooplankton size classes were generally distinguishable by their dietary fatty acids, while stable isotopes revealed more seasonal variability. Fatty acids of zooplankton were correlated with those of their prey (particulate organic matter and smaller zooplankton) and identified trophic pathways, including widespread ties to the microbial food web. Diatom fatty acids also contributed to zooplankton but fall blooms were more important than spring. Concurrent isotope-based trophic position estimates and fatty acid markers of carnivory showed that some indicators (18:1ω9/18:1ω7) are not consistent across size classes, while others (DHA:EPA) are relatively reliable. Both analysis methods provided distinct information to build a more robust understanding of resource use. For example, fatty acid markers showed that trophic position was likely underestimated in 250-µm zooplankton, probably due to their consumption of protists with low isotopic fractionation factors. Applying fatty acid analysis to a size-structured framework provides more insight into trophic pathways than isotopes alone.


Asunto(s)
Cadena Alimentaria , Zooplancton , Animales , Estaciones del Año , Isótopos/metabolismo , Ácidos Grasos/metabolismo , Fitoplancton
6.
Neural Netw ; 170: 94-110, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37977092

RESUMEN

Recent work has shown that machine learning (ML) models can skillfully forecast the dynamics of unknown chaotic systems. Short-term predictions of the state evolution and long-term predictions of the statistical patterns of the dynamics ("climate") can be produced by employing a feedback loop, whereby the model is trained to predict forward only one time step, then the model output is used as input for multiple time steps. In the absence of mitigating techniques, however, this feedback can result in artificially rapid error growth ("instability"). One established mitigating technique is to add noise to the ML model training input. Based on this technique, we formulate a new penalty term in the loss function for ML models with memory of past inputs that deterministically approximates the effect of many small, independent noise realizations added to the model input during training. We refer to this penalty and the resulting regularization as Linearized Multi-Noise Training (LMNT). We systematically examine the effect of LMNT, input noise, and other established regularization techniques in a case study using reservoir computing, a machine learning method using recurrent neural networks, to predict the spatiotemporal chaotic Kuramoto-Sivashinsky equation. We find that reservoir computers trained with noise or with LMNT produce climate predictions that appear to be indefinitely stable and have a climate very similar to the true system, while the short-term forecasts are substantially more accurate than those trained with other regularization techniques. Finally, we show the deterministic aspect of our LMNT regularization facilitates fast reservoir computer regularization hyperparameter tuning.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación , Computadores , Predicción
7.
Mar Environ Res ; 191: 106171, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37716280

RESUMEN

Global climate change is projected to raise global temperatures by 3.3-5.7 °C by 2100, resulting in changes in species composition, abundance, and nutritional quality of organisms at the base of the marine food web. Predicted increases in prey availability and reductions in prey nutritional quality under climate warming in certain marine systems are expected to impact higher trophic levels, such as fish and humans. There is limited knowledge of the interplay between food quantity and quality under warming, specifically when food availability is high, but quality is low. Here, we conducted an experiment assessing the effects of food quality (fatty acid composition and ratios) on juvenile Chinook salmon's (Oncorhynchus tshawytscha) body and nutritional condition, specifically focusing on RNA:DNA ratio, Fulton's K, growth, mortality and their fatty acid composition. Experimental diets represented three different climate change scenarios with 1) a present-day diet (Euphausia pacifica), 2) a control diet (commercial aquaculture diet), and 3) a predicted Intergovernmental Panel on Climate Change (IPCC) worst-case scenario diet with low essential fatty acid concentrations (IPCC SSP5-8.5). We tested how growth rates, RNA:DNA ratio, Fulton's K index, fatty acid composition and mortality rates in juvenile Chinook salmon compared across diet treatments. Fatty acids were incorporated into the salmon muscle at varying rates but, on average, reflected dietary concentrations. High dietary concentrations of DHA, EPA and high DHA:EPA ratios, under the control and present-day diets, increased fish growth and condition. In contrast, low concentrations of DHA and EPA and low DHA:EPA ratios in the diets under climate change scenario were not compensated for by increased food quantity. This result highlights the importance of considering food quality when assessing fish response to changing ocean conditions.


Asunto(s)
Cambio Climático , Salmón , Humanos , Animales , Ácidos Docosahexaenoicos , Ácidos Grasos , Peces , Calidad de los Alimentos
8.
Psychiatry Res ; 327: 115366, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37542792

RESUMEN

Contemporary literature and recent classification systems have expanded the field of addictions to include problematic behaviours such as gambling and sexual addiction. However, conceptualisation of behavioural addictions is poorly understood and gender-based differences have emerged in relation to how these behaviours are expressed. The current research conducted partial-correlation and Bayesian network analyses to assess the symptomatic structure of gambling disorder and sexual addiction. Convenience community sampling recruited 937 adults aged 18 to 64 years (315 females, Mage = 30.02; 622 males, Mage = 29.46). Symptoms of problematic behaviours were measured using the Online Gambling Disorder Questionnaire (OGDQ) and the Bergen Yale Sex Addiction Scale (BYSAS). Results indicate distinct gender-based differences in the symptom networks of sexual addiction and gambling disorder, with a more complex network observed amongst men for both conditions. Addiction salience, withdrawal and dishonesty/deception were important components of the addictive network. Interpersonal conflict was more central for women while intrapsychic conflict a more prominent issue for men. Differences in the two symptom networks indicate separate disorders as opposed to a single underlying construct. Treating practitioners and community initiatives aimed at addressing sexual addiction and disordered gambling should consider gender, when designing educational or therapeutic interventions.


Asunto(s)
Conducta Adictiva , Juego de Azar , Masculino , Adulto , Humanos , Femenino , Juego de Azar/epidemiología , Juego de Azar/diagnóstico , Teorema de Bayes , Conducta Adictiva/epidemiología , Conducta Adictiva/diagnóstico , Encuestas y Cuestionarios , Escolaridad
9.
J Parasitol ; 109(3): 221-224, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37327396

RESUMEN

Toxoplasma gondii is an important protozoan parasite of humans and animals throughout the world. Black bears are among the animals with the highest seroprevalence of T. gondii in the United States. A rapid point of care (POC) test is commercially available to detect antibodies to T. gondii in humans. We evaluated the utility of the POC test to detect anti-T. gondii antibodies in 100 wild black bears from North Carolina (n = 50) and Pennsylvania (n = 50). In a blind study, sera were tested by the POC test, and results were compared to the modified agglutination test (MAT). Overall, anti-T. gondii antibodies were detected in 76% (76/100) black bears by both MAT and POC tests. One false positive and one false negative result in the POC test were obtained in bears from Pennsylvania. The sensitivity and specificity of the POC test were both 99% when compared to the MAT. Results from our study indicate the POC test could be a useful screening tool for serological surveillance of T. gondii in black bears.


Asunto(s)
Toxoplasma , Toxoplasmosis Animal , Ursidae , Animales , Humanos , Ursidae/parasitología , Anticuerpos Antiprotozoarios , Pennsylvania/epidemiología , North Carolina/epidemiología , Prevalencia , Estudios Seroepidemiológicos , Toxoplasmosis Animal/diagnóstico , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/parasitología , Pruebas de Aglutinación/veterinaria
10.
PLoS Pathog ; 19(6): e1011386, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37347729

RESUMEN

Sea lice, the major ectoparasites of fish, have significant economic impacts on wild and farmed finfish, and have been implicated in the decline of wild salmon populations. As blood-feeding arthropods, sea lice may also be reservoirs for viruses infecting fish. However, except for two groups of negative-strand RNA viruses within the order Mononegavirales, nothing is known about viruses of sea lice. Here, we used transcriptomic data from three key species of sea lice (Lepeophtheirus salmonis, Caligus clemensi, and Caligus rogercresseyi) to identify 32 previously unknown RNA viruses. The viruses encompassed all the existing phyla of RNA viruses, with many placed in deeply branching lineages that likely represent new families and genera. Importantly, the presence of canonical virus-derived small interfering RNAs (viRNAs) indicates that most of these viruses infect sea lice, even though in some cases their closest classified relatives are only known to infect plants or fungi. We also identified both viRNAs and PIWI-interacting RNAs (piRNAs) from sequences of a bunya-like and two qin-like viruses in C. rogercresseyi. Our analyses showed that most of the viruses found in C. rogercresseyi occurred in multiple life stages, spanning from planktonic to parasitic stages. Phylogenetic analysis revealed that many of the viruses infecting sea lice were closely related to those that infect a wide array of eukaryotes with which arthropods associate, including fungi and parasitic tapeworms, implying that over evolutionary time there has been cross-phylum and cross-kingdom switching of viruses between arthropods and other eukaryotes. Overall, this study greatly expands our view of virus diversity in crustaceans, identifies viruses that infect and replicate in sea lice, and provides evidence that over evolutionary time, viruses have switched between arthropods and eukaryotic hosts in other phyla and kingdoms.


Asunto(s)
Copépodos , Enfermedades de los Peces , Virus ARN , Animales , Copépodos/genética , Filogenia , Virus ARN/genética , Salmón/genética , Salmón/parasitología , ARN Interferente Pequeño
11.
Oncogene ; 42(21): 1716-1727, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37029299

RESUMEN

Recurrence remains a significant clinical barrier to improving breast cancer patient outcomes. The RON receptor is a predictor of metastatic progression and recurrence in breast cancers of all subtypes. RON directed therapies are in development, but preclinical data directly testing the impact of RON inhibition on metastatic progression/recurrence are lacking, and mechanisms to exert this function remain unclear. Herein, we modeled breast cancer recurrence using implantation of RON-overexpressing murine breast cancer cells. Recurrent growth was examined after tumor resection via in vivo imaging and ex vivo culture of circulating tumor cells from whole blood samples from tumor bearing mice. In vitro functional assessment of was performed using mammosphere formation assays. Transcriptomic pathway enrichment identified glycolysis and cholesterol biosynthesis pathways, transcription factor targets, and signaling pathways enriched in RON-overexpressing breast cancer cells. BMS777607, a RON inhibitor, abrogated CTC colony formation tumor cells and tumor recurrence. RON promoted mammosphere formation through upregulated cholesterol production that utilizes glycolysis-derived substrates. In mouse models with RON overexpression, statin-mediated inhibition of cholesterol biosynthesis impeded metastatic progression and recurrence but does not affect the primary tumor. RON upregulates glycolysis and cholesterol biosynthesis gene expression by two pathways: MAPK-dependent c-Myc expression and ß-catenin -dependent SREBP2 expression.


Asunto(s)
Recurrencia Local de Neoplasia , Proteínas Tirosina Quinasas Receptoras , Animales , Ratones , Línea Celular Tumoral , Modelos Animales de Enfermedad , Recurrencia Local de Neoplasia/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal
12.
Genes (Basel) ; 14(2)2023 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-36833444

RESUMEN

RON is a receptor tyrosine kinase (RTK) of the MET receptor family that is canonically involved in mediating growth and inflammatory signaling. RON is expressed at low levels in a variety of tissues, but its overexpression and activation have been associated with malignancies in multiple tissue types and worse patient outcomes. RON and its ligand HGFL demonstrate cross-talk with other growth receptors and, consequentially, positions RON at the intersection of numerous tumorigenic signaling programs. For this reason, RON is an attractive therapeutic target in cancer research. A better understanding of homeostatic and oncogenic RON activity serves to enhance clinical insights in treating RON-expressing cancers.


Asunto(s)
Neoplasias , Proteínas Proto-Oncogénicas , Proteínas Tirosina Quinasas Receptoras , Humanos , Factor de Crecimiento de Hepatocito , Ligandos , Proteínas Proto-Oncogénicas/metabolismo , Transducción de Señal
13.
Sci Rep ; 13(1): 2675, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36792655

RESUMEN

In Southern British Columbia (BC), Canada, declines in southern resident killer whale (SRKW-Orcinus orca) populations have been linked to declines in numbers and average size of their preferred prey, Chinook salmon (Oncorhynchus tshawytscha). However, the life history diversity of Chinook suggests that there is a need to assess stock-specific differences in energy density to evaluate prey quality as a factor in SRKW declines. In this study, we calibrated a Distell fat meter to estimate Chinook whole-body lipid content, a proxy for energy density. The fat meter was deployed at the Fraser River, BC, Chinook test fishery during 2020, collecting lipid, weight, and length measurements from 1566 genetically stock identified individuals encompassing all major Fraser River Chinook population units (management units, MUs) at river entry. We found that MU-specific lipid content increased with distance and elevation to spawning grounds and was highest in the Spring-52 (12.8%) and Summer-52 (12.7%) MUs, intermediate in the Summer-41 MU (10.8%), and lowest in the Fall-41 MU (7.3%). Lipid content also decreased by up to 6 percentage points within MUs from the beginning to end of their migration period. Our data revealed SRKWs' most endangered prey sources, the Spring-52 and Summer-52 MUs, are also its most energy rich. It also indicated SRKWs have access to progressively lower energy density Chinook through the year, requiring up to ~ 30% more fish to meet energy demands in the fall than in the spring.


Asunto(s)
Salmón , Orca , Animales , Estaciones del Año , Ríos , Colombia Británica , Lípidos
14.
PLoS One ; 17(9): e0274128, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36067206

RESUMEN

BACKGROUND: Advances in detection techniques and treatment have increased the diagnosis of breast cancer at early stages; however, recurrence occurs in all breast cancer subtypes, and both recurrent and de novo metastasis are typically treatment resistant. A growing body of evidence supports the notion that metabolic plasticity drives cancer recurrence. RON and DEK are proteins that promote cancer metastasis and synergize mechanistically to activate ß-catenin, but the metabolic consequences are unknown. METHODS: To ascertain RON-DEK-ß-catenin dependent metabolic pathways, we utilized an NMR-based metabolomics approach to determine steady state levels of metabolites. We also interrogated altered metabolic pathway gene expression for prognostic capacity in breast cancer patient relapse-free and distant metastasis-free survival and discover a metabolic signature that is likely associated with recurrence. RESULTS: RON-DEK-ß-catenin loss showed a consistent metabolite regulation of succinate and phosphocreatine. Consistent metabolite alterations between RON and DEK loss (but not ß-catenin) were found in media glucose consumption, lactate secretion, acetate secretion, and intracellular glutamine and glutathione levels. Consistent metabolite alterations between RON and ß-catenin loss (and not DEK) were found only in intracellular lactate levels. Further pathway hits include ß-catenin include glycolysis, glycosylation, TCA cycle/anaplerosis, NAD+ production, and creatine dynamics. Genes in these pathways epistatic to RON-DEK-ß-catenin were used to define a gene signature that prognosticates breast cancer patient survival and response to chemotherapy. CONCLUSIONS: The RON-DEK-ß-catenin axis regulates the numerous metabolic pathways with significant associations to breast cancer patient outcomes.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proteínas Cromosómicas no Histona/genética , Lactatos , Redes y Vías Metabólicas , Recurrencia Local de Neoplasia , Proteínas Oncogénicas/genética , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo
15.
Prostate ; 82(15): 1422-1437, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35860905

RESUMEN

BACKGROUND: Androgen deprivation therapy (ADT), or chemical castration, is the first-line therapy for prostate cancer; however, resistance leaves few treatment options. Prostatic tumor-associated macrophages (TAMs) have been shown to promote prostate cancer growth and are abundant in castration-resistant prostate cancer (CRPC), suggesting a role in promoting CRPC. We recently showed a tumor cell-intrinsic mechanism by which RON promotes CRPC. Given previous reports that RON alters prostate cancer cell chemokine production and RON-overexpressing tumors alter macrophage function, we hypothesized that a macrophage-dependent mechanism regulated by tumor cell intrinsic RON also promotes CRPC. METHODS: Using RON-modulated genetically engineered mouse models (GEMMs) and GEMM-derived cell lines and co-cultures with bone marrow-derived macrophages, we show functional and molecular characteristics of signaling pathways in supporting CRPC. Further, we used an unbiased phosphokinase array to identify pathway interactions regulated by RON. Finally, using human prostate cancer cell lines and prostate cancer patient data sets, we show the relevance of our findings to human prostate cancer. RESULTS: Studies herein show that macrophages recruited into the prostate tumor microenvironment (TME) serve as a source for Gas6 secretion which serves to further enhance RON and Axl receptor activation in prostate tumor cells thereby driving CRPC. Further, we show targeting RON and macrophages in a murine model promotes CRPC sensitization to ADT. CONCLUSIONS: We discovered a novel role for the RON receptor in prostate cancer cells in promoting CRPC through the recruitment of macrophages into the prostate TME. Macrophage-targeting agents in combination with RON/Axl inhibition are likely to provide clinical benefits for patients with CRPC.


Asunto(s)
Antagonistas de Andrógenos , Andrógenos , Macrófagos , Neoplasias de la Próstata Resistentes a la Castración , Proteínas Tirosina Quinasas Receptoras , Antagonistas de Andrógenos/uso terapéutico , Andrógenos/metabolismo , Animales , Quimiocinas/metabolismo , Humanos , Macrófagos/inmunología , Masculino , Ratones , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/inmunología , Microambiente Tumoral
16.
Sci Rep ; 12(1): 12270, 2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35851610

RESUMEN

Ocean acidification can negatively impact the early life-stages of marine fish, due to energetic costs incurred by the maintenance of acid-base homeostasis, leaving less energy available for growth and development. The embryos of intertidally spawning fishes, such as Pacific herring, are often air exposed for hours. We hypothesized that air exposure would be beneficial to the developing embryo due to a higher oxygen availability (and thus reduced metabolic costs to secure adequate oxygen) and permitting excess CO2 associated with ocean acidification to be off-gassed during emersion. To investigate this, we reared Pacific herring (Clupea pallasii) embryos under three tidal regimes (subtidal: fully immersed, low intertidal: 2 × 2 h air exposure, and high intertidal: 5 + 9 h air exposure) fully crossed with three aquatic CO2 levels (400, 1500 and 3200 µatm) at a water temperature of 9.5 °C and naturally fluctuating air temperature during air exposure. We measured the effects on embryonic development and hatch, as well as carry-over effects on larval development and survival. Air exposure during embryonic development had significant positive effects on growth, condition and survival in larval Pacific herring, with some interactive effects with CO2. Interestingly, CO2 by itself in the fully immersed treatment had no effect, but had significant interactions with air exposure. Our research suggests that air exposure during low tide can be highly beneficial to intertidally spawning fishes and needs to be taken into account in climate change studies and modeling.


Asunto(s)
Dióxido de Carbono , Agua de Mar , Animales , Dióxido de Carbono/metabolismo , Desarrollo Embrionario , Peces , Homeostasis , Concentración de Iones de Hidrógeno , Océanos y Mares , Oxígeno/metabolismo
17.
Cancers (Basel) ; 14(10)2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35626096

RESUMEN

BACKGROUND: Aberrant RON signaling is present in numerous cancers including breast cancer. Evidence suggests that the ligand, hepatocyte growth factor-like (HGFL), is also overexpressed in breast cancer. RON (MST1R) and HGFL (MST1) genes are located on human chromosome 3 and mouse chromosome 9 respectively and are found near each other in both species. Based on co-expression patterns, we posited that RON and HGFL are co-regulated and that coordinate upregulation drives aggressive tumorigenesis. METHODS: Mouse models were used to establish the functional significance of RON and HGFL co-overexpression on the activation of tumor cells and tumor-associated macrophages in breast cancer. TCGA and METABRIC gene expression and alteration data were used to query the relationships between MST1R and MST1 in breast cancer. RESULTS: In tumor models, physiologic sources of HGFL modestly improve Arginase-1+ (M2) macrophage recruitment to the tumor proper. Tumor-cell produced HGFL functions in autocrine to sustain tumor cell RON activation and MAPK-dependent secretion of chemotactic factors and in paracrine to activate RON on macrophages and to promote breast cancer stem cell self-renewal. In silico analyses support that RON and HGFL are co-expressed across virtually all cancer types including breast cancer and that common genomic alterations do not appear to be drivers of RON/HGFL co-overexpression. CONCLUSIONS: Co-overexpression of RON and HGFL in breast cancer cells (augmented by physiologic sources of HGFL) promotes tumorigenesis through autocrine-mediated RON activation/RON-dependent secretome changes and paracrine activation of macrophage RON to promote breast cancer stem cell self-renewal.

18.
Oncogene ; 41(3): 321-333, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34743208

RESUMEN

Tumor associated macrophages (TAMs) play a major role in regulating mammary tumor growth and in directing the responses of tumor infiltrating leukocytes in the microenvironment. However, macrophage-specific mechanisms regulating the interactions of macrophages with tumor cells and other leukocytes that support tumor progression have not been extensively studied. In this study, we show that the activation of the RON receptor tyrosine kinase signaling pathway specifically in macrophages supports breast cancer growth and metastasis. Using clinically relevant murine models of breast cancer, we demonstrate that loss of macrophage RON expression results in decreases in mammary tumor cell proliferation, survival, cancer stem cell self-renewal, and metastasis. Macrophage RON signaling modulates these phenotypes via direct effects on the tumor proper and indirectly by regulating leukocyte recruitment including macrophages, T-cells, and B-cells in the mammary tumor microenvironment. We further show that macrophage RON expression regulates the macrophage secretome including IL-35 and other immunosuppressive factors. Overall, our studies implicate activation of RON signaling in macrophages as a key player in supporting a thriving mammary pro-tumor microenvironment through novel mechanisms including the augmentation of tumor cell properties through IL-35.


Asunto(s)
Neoplasias de la Mama/genética , Interleucinas/metabolismo , Macrófagos/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Femenino , Humanos , Ratones , Metástasis de la Neoplasia , Transducción de Señal , Microambiente Tumoral
19.
PeerJ ; 9: e12238, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34721967

RESUMEN

The temporal dynamics of five copepod species common to coastal waters of the Pacific Northwest were examined in relation to variability in spring temperature and phytoplankton dynamics in 2008, 2009, and 2010 in Rivers Inlet, British Columbia, Canada. The five species were differentiated by life history strategies. Acartia longiremis, Metridia pacifica, and Paraeuchaeta elongata remained active over most of the year. By contrast, the reproductive effort of Eucalanus bungii and Calanus marshallae was concentrated over the spring period and they spent most of the year in diapause as C5 copepodites. A delay in the timing of the spring bloom was associated with a shift in the phenology of all species. However, following the delay in spring bloom timing, recruitment to the G1 cohort was reduced only for E. bungii and C. marshallae. Recruitment successes of E. bungii and C. marshallae was also drastically reduced in 2010, an El Niño year, when spring temperatures were highest. Reasons for the observed differential response to spring environmental forcing, and its effect on upper trophic levels, are discussed.

20.
Brain Commun ; 3(3): fcab188, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34704026

RESUMEN

High frequency oscillations (HFOs) are very brief events that are a well-established biomarker of the epileptogenic zone (EZ) but are rare and comprise only a tiny fraction of the total recorded EEG. We hypothesize that the interictal high frequency 'background' data, which has received little attention but represents the majority of the EEG record, also may contain additional, novel information for identifying the EZ. We analysed intracranial EEG (30-500 Hz frequency range) acquired from 24 patients who underwent resective surgery. We computed 38 quantitative features based on all usable, interictal data (63-307 h per subject), excluding all detected HFOs. We assessed association between each feature and the seizure onset zone (SOZ) and resected volume (RV) using logistic regression. A pathology score per channel was also created via principle component analysis and logistic regression, using hold-out-one-patient cross-validation to avoid in-sample training. Association of the pathology score with the SOZ and RV was quantified using an asymmetry measure. Many features were associated with the SOZ: 23/38 features had odds ratios >1.3 or <0.7 and 17/38 had odds ratios different than zero with high significance (P < 0.001/39, logistic regression with Bonferroni Correction). The pathology score, the rate of HFOs, and their channel-wise product were each strongly associated with the SOZ [median asymmetry ≥0.44, good surgery outcome patients; median asymmetry ≥0.40, patients with other outcomes; 95% confidence interval (CI) > 0.27 in both cases]. The pathology score and the channel-wise product also had higher asymmetry with respect to the SOZ than the HFO rate alone (median difference in asymmetry ≥0.18, 95% CI >0.05). These results support that the high frequency background data contains useful information for determining the EZ, distinct and complementary to information from detected HFOs. The concordance between the high frequency activity pathology score and the rate of HFOs appears to be a better biomarker of epileptic tissue than either measure alone.

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