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1.
Clin Immunol ; 262: 110183, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479439

RESUMO

Vitamin D deficiency is a risk factor for developing multiple sclerosis. The PrevANZ trial was conducted to determine if vitamin D3 supplementation can prevent recurrent disease activity in people with a first demyelinating event. As a sub-study of this trial, we investigated the effect of supplementation on peripheral immune cell gene expression. Participants were randomized to 1000, 5000 or 10,000 international units daily of vitamin D3 or placebo. Peripheral blood was collected at baseline and 12 weeks and sent for ribonucleic acid sequencing. Datasets from 55 participants were included. Gene expression was modulated by high dose supplementation. Antigen presentation and viral response pathways were upregulated. Oxidative phosphorylation and immune signaling pathways, including tumor necrosis factor-alpha and interleukin-17 signaling, were downregulated. Overall, vitamin D3 supplementation for 12 weeks modulated the peripheral immune cell transcriptome with induction of anti-inflammatory gene expression profiles. Our results support a dose-dependent effect of vitamin D3 supplementation on immune gene expression.


Assuntos
Colecalciferol , Deficiência de Vitamina D , Humanos , Colecalciferol/farmacologia , Colecalciferol/uso terapêutico , Transcriptoma , Suplementos Nutricionais , Deficiência de Vitamina D/tratamento farmacológico , Deficiência de Vitamina D/genética , Fatores de Risco , Vitamina D/uso terapêutico , Método Duplo-Cego
2.
Am Nat ; 201(4): 586-602, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36958006

RESUMO

AbstractUnifying models have shown that the amount of space used by animals (e.g., activity space, home range) scales allometrically with body mass for terrestrial taxa; however, such relationships are far less clear for marine species. We compiled movement data from 1,596 individuals across 79 taxa collected using a continental passive acoustic telemetry network of acoustic receivers to assess allometric scaling of activity space. We found that ectothermic marine taxa do exhibit allometric scaling for activity space, with an overall scaling exponent of 0.64. However, body mass alone explained only 35% of the variation, with the remaining variation best explained by trophic position for teleosts and latitude for sharks, rays, and marine reptiles. Taxon-specific allometric relationships highlighted weaker scaling exponents among teleost fish species (0.07) than sharks (0.96), rays (0.55), and marine reptiles (0.57). The allometric scaling relationship and scaling exponents for the marine taxonomic groups examined were lower than those reported from studies that had collated both marine and terrestrial species data derived using various tracking methods. We propose that these disparities arise because previous work integrated summarized data across many studies that used differing methods for collecting and quantifying activity space, introducing considerable uncertainty into slope estimates. Our findings highlight the benefit of using large-scale, coordinated animal biotelemetry networks to address cross-taxa evolutionary and ecological questions.


Assuntos
Organismos Aquáticos , Peixes , Animais , Comportamento de Retorno ao Território Vital
3.
Ecol Evol ; 13(3): e9885, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36937069

RESUMO

The advancement and availability of innovative animal biotelemetry and genomic technologies are improving our understanding of how the movements of individuals influence gene flow within and between populations and ultimately drive evolutionary and ecological processes. There is a growing body of work that is integrating what were once disparate fields of biology, and here, we reviewed the published literature up until January 2023 (139 papers) to better understand the drivers of this research and how it is improving our knowledge of animal biology. The review showed that the predominant drivers for this research were as follows: (1) understanding how individual-based movements affect animal populations, (2) analyzing the relationship between genetic relatedness and social structuring, and (3) studying how the landscape affects the flow of genes, and how this is impacted by environmental change. However, there was a divergence between taxa as to the most prevalent research aim and the methodologies applied. We also found that after 2010 there was an increase in studies that integrated the two data types using innovative statistical techniques instead of analyzing the data independently using traditional statistics from the respective fields. This new approach greatly improved our understanding of the link between the individual, the population, and the environment and is being used to better conserve and manage species. We discuss the challenges and limitations, as well as the potential for growth and diversification of this research approach. The paper provides a guide for researchers who wish to consider applying these disparate disciplines and advance the field.

4.
Glob Chang Biol ; 28(19): 5781-5792, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35923070

RESUMO

With rising ocean temperatures, extreme weather events such as marine heatwaves (MHWs) are increasing in frequency and duration, pushing marine life beyond their physiological limits. The potential to respond to extreme conditions through physiological acclimatization, and pass on resistance to the next generation, fundamentally depends on the capacity of an organism to cope within their thermal tolerance limits. To elucidate whether heat conditioning of parents could benefit offspring development, we exposed adult sea urchins (Heliocidaris erythrogramma) to ambient summer (23°C), moderate (25°C) or strong (26°C) MHW conditions for 10 days. Offspring were then reared at constant temperature along a thermal gradient (22-28°C) and development was tracked to the 14-day juvenile stage. Progeny from the MHW-conditioned adults developed through to metamorphosis faster than those of ambient conditioned parents, with most individuals from the moderate and strong heatwaves developing to the larval stage across all temperatures. In contrast, the majority of offspring from the control summer temperature died before metamorphosis at temperatures above 25°C (moderate MHW). Juveniles produced from the strong MHW-conditioned adults were also larger across all temperatures, with the largest juveniles in the 26°C treatment. In contrast, the smallest juveniles were from control (current-day summer) parents (and reared at 22 and 25°C). Surprisingly, initial survival was higher in the progeny of MHW exposed parents, even at temperatures hotter than predicted MHWs (28°C). Importantly, however, there was substantial mortality of juveniles from the strong MHW parents by day 14. Therefore, while carryover effects of parental conditioning to MHWs resulted in faster growing, larger progeny, this benefit will only persist beyond the more sensitive juvenile stage and enhance survival if conditions return promptly to normal seasonal temperatures within current thermal tolerance limits.


Assuntos
Temperatura Alta , Ouriços-do-Mar , Animais , Humanos , Estações do Ano , Temperatura
5.
Biol Lett ; 18(4): 20210676, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35472283

RESUMO

Supporting the recovery of large carnivores is a popular yet challenging endeavour. Estuarine crocodiles in Australia are a large carnivore conservation success story, with the population having extensively recovered from past heavy exploitation. Here, we explored if dietary changes had accompanied this large population recovery by comparing the isotopes δ13C and δ15N in bones of crocodiles sampled 40 to 55 years ago (small population) with bones from contemporary individuals (large population). We found that δ13C and δ15N values were significantly lower in contemporary crocodiles than in the historical cohort, inferring a shift in prey preference away from marine and into terrestrial food webs. We propose that an increase in intraspecific competition within the recovering crocodile population, alongside an increased abundance of feral ungulates occupying the floodplains, may have resulted in the crocodile population shifting to feed predominantly upon terrestrial food sources. The number of feral pigs consumed to sustain and grow crocodile biomass may help suppress pig population growth and increase the flow of terrestrially derived nutrients into aquatic ecosystems. The study highlights the significance of prey availability in contributing to large carnivore population recovery.


Assuntos
Ecossistema , Comportamento Predatório , Animais , Dieta , Cadeia Alimentar , Humanos , Sus scrofa , Suínos
6.
Glob Chang Biol ; 28(9): 3040-3053, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35108424

RESUMO

For marine ectotherms, larval success, planktonic larval duration and dispersal trajectories are strongly influenced by temperature, and therefore, ocean warming and heatwaves have profound impacts on these sensitive stages. Warming, through increased poleward flow in regions with western boundary currents, such as the East Australia Current (EAC), provides opportunities for range extension as propagules track preferred conditions. Two sea urchin species, Centrostephanus rodgersii and Heliocidaris tuberculata, sympatric in the EAC warming hotspot, exhibit contrasting responses to warming. Over half a century, C. rodgersii has undergone marked poleward range extension, but the range of H. tuberculata has not changed. We constructed thermal performance curves (TPC) to determine if contrasting developmental thermal tolerance can explain this difference. The temperatures tested encompassed present-day distribution and forecast ocean warming/heatwave conditions. The broad and narrow thermal optimum (Topt) ranges for C. rodgersii and H. tuberculata larvae (7.2 and 4.7°C range, respectively) matched their realized (adult distribution) thermal niches. The cool and warm temperatures for 50% development to the feeding larva approximated temperatures at adult poleward range limits. Larval cool tolerances with respect to mean local temperature differed, 6.0 and 3.8°C respectively. Larval warm tolerances were similar for both species as are the adult warm range edges. The larvae of both species would be sensitive to heatwaves. Centrostephanus rodgersii has stayed in place and shifted in space, likely due to its broad cold-warm larval thermal tolerance and large thermal safety margins. Phenotypic plasticity of the planktonic stage of C. rodgersii facilitated its range extension. In contrast, larval cold intolerance of H. tuberculata explains its restricted range and will delay poleward extension as the region warms. In a warming ocean, we show that intrinsic thermal biology traits of the pelagic stage provide an integrative tool to explain species-specific variation in range shift patterns.


Assuntos
Ecossistema , Ouriços-do-Mar , Adaptação Fisiológica , Animais , Larva/fisiologia , Ouriços-do-Mar/fisiologia , Temperatura
7.
Mol Oncol ; 16(2): 447-465, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34657382

RESUMO

Breast cancer is the most diagnosed malignancy in women, with over half a million women dying from this disease each year. In our previous studies, ∆40p53, an N-terminally truncated p53 isoform, was found to be upregulated in breast cancers, and a high ∆40p53 : p53α ratio was linked with worse disease-free survival. Although p53α inhibits cancer migration and invasion, little is known about the role of ∆40p53 in regulating these metastasis-related processes and its role in contributing to worse prognosis. The aim of this study was to assess the role of ∆40p53 in breast cancer migration and invasion. A relationship between Δ40p53 and gene expression profiles was identified in oestrogen-receptor-positive breast cancer specimens. To further evaluate the role of Δ40p53 in oestrogen-receptor-positive breast cancer, MCF-7 and ZR75-1 cell lines were transduced to knockdown p53α or Δ40p53 and overexpress Δ40p53. Proliferation, migration and invasion were assessed in the transduced sublines, and gene expression was assessed through RNA-sequencing and validated by reverse-transcription quantitative PCR. Knockdown of both p53α and ∆40p53 resulted in increased proliferation, whereas overexpression of ∆40p53 reduced proliferation rates. p53α knockdown was also associated with increased cell mobility. ∆40p53 overexpression reduced both migratory and invasive properties of the transduced cells. Phenotypic findings are supported by gene expression data, including differential expression of LRG1, HYOU1, UBE2QL1, SERPINA5 and PCDH7. Taken together, these results suggest that, at the basal level, ∆40p53 works similarly to p53α in suppressing cellular mobility and proliferation, although the role of Δ40p53 may be cell context-specific.


Assuntos
Neoplasias da Mama/patologia , Invasividade Neoplásica , Metástase Neoplásica , Isoformas de Proteínas/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Isoformas de Proteínas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p53/genética
8.
Mol Ecol ; 31(4): 1076-1092, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34865283

RESUMO

Landscape genetics commonly focuses on the effects of environmental resistance on animal dispersal patterns, but there is an emerging focus on testing environmental effects on emigration and settlement choices. In this study, we used landscape genetics approaches to quantify dispersal patterns in the world's largest crocodilian, the saltwater crocodile (Crocodylus porosus), and demonstrated environmental influences on three processes that comprise dispersal: emigration, movement and settlement. We found that both environmental resistance and properties of the source and destination catchments (proportion of breeding habitat) were important factors influencing observed dispersal events. Our habitat quality variables related to hypotheses about resource competition and represented the ratio of breeding habitat (which limits carrying capacity), suggesting that competition for habitat influences emigration and settlement choices, together with the strong effect of environmental resistance to movement (where high-quality habitat was associated with greatest environmental permeability). Approximately 42% of crocodiles were migrants from populations other than their sampling locations and some outstandingly productive populations had a much higher proportion of emigration rather than immigration. The distance most commonly travelled between source and destination was 150-200 km although a few travelled much longer distances, up to 600-700 km. Given the extensive dispersal range, individual catchments or hydrographic regions that combine two or three adjacent catchments are an appropriate scale for population management.


Assuntos
Jacarés e Crocodilos , Jacarés e Crocodilos/genética , Distribuição Animal , Animais , Clima , Ecossistema
9.
EMBO Rep ; 22(12): e53085, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34779563

RESUMO

All living organisms have developed processes to sense and address environmental changes to maintain a stable internal state (homeostasis). When activated, the p53 tumour suppressor maintains cell and organ integrity and functions in response to homeostasis disruptors (stresses) such as infection, metabolic alterations and cellular damage. Thus, p53 plays a fundamental physiological role in maintaining organismal homeostasis. The TP53 gene encodes a network of proteins (p53 isoforms) with similar and distinct biochemical functions. The p53 network carries out multiple biological activities enabling cooperation between individual cells required for long-term survival of multicellular organisms (animals) in response to an ever-changing environment caused by mutation, infection, metabolic alteration or damage. In this review, we suggest that the p53 network has evolved as an adaptive response to pathogen infections and other environmental selection pressures.


Assuntos
Genes p53 , Homeostase , Proteína Supressora de Tumor p53 , Animais , Infecções , Mutação , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estresse Fisiológico , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
10.
Sci Total Environ ; 797: 149215, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34346350

RESUMO

Marine heatwaves are occurring with greater frequency and magnitude worldwide and can significantly alter community structure and ecosystem function. Predicting changes in community structure in extreme temperatures requires an understanding of variation among species in their thermal tolerance, and how potential acclimatization to recent temperatures influences survival. To address this, we determined the tolerance to extreme temperatures in a crustacean epifaunal assemblage that inhabits macroalgae in the southeast Australian ocean warming hotspot. Amphipods were the most abundant group and the thermal tolerance of the most abundant species (two in winter and four in summer) was tested to determine their thermal limits and probability of survival in near-future extreme temperatures. Survival, measured as time to immobilization, was compared across species, sexes, life stage and body size. The greatest variation in tolerance to extreme temperatures was among species (not body sizes or life stages), indicating that heatwaves could shift the composition of the macroalgal associated epifaunal assemblage. Comparison of recent thermal history (between 18 °C to 22 °C) revealed greater thermal tolerance of warm acclimatized individuals. Our results indicate that the impacts of a marine heatwave will depend on local species composition and their timing relative to recent climate conditions.


Assuntos
Aclimatação , Ecossistema , Austrália , Humanos , Estações do Ano , Temperatura
11.
Mar Pollut Bull ; 163: 111914, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33385800

RESUMO

For short development species, like the sea urchin Heliocidaris erythrogramma, the entire planktonic duration can be impacted by marine heatwaves (MHW). Developmental thermal tolerance of this species through metamorphosis was investigated over a broad range (7.6-28.0 °C), including temperatures across its distribution and MHW conditions. In controls (19.5-21.0 °C), 80% of individuals developed to metamorphosis at day 5, doubling to 10 days at 14.0 °C. The thermal range (14.4-21.2 °C) of metamorphosis on day 7 reflected the realised thermal niche with 25.9 °C the upper temperature for success (T40). By day 10, juvenile tolerance narrowed to the local range (16.2-19.0 °C), similar to levels tolerated by adults, indicating negative carryover effects across the metamorphic transition. Without phenotypic adjustment or adaptation, regional warming will be detrimental, although populations may be sustained by thermotolerant offspring. Our results show the importance of the metamorphic transition in understanding the cumulative sensitivity of species to MHW.


Assuntos
Anthocidaris , Aclimatação , Adaptação Fisiológica , Animais , Humanos , Ouriços-do-Mar , Temperatura
12.
PLoS One ; 15(11): e0241964, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33216810

RESUMO

Anthropogenic derived environmental change is challenging earth's biodiversity. To implement effective management, it is imperative to understand how organisms are responding over broad spatiotemporal scales. Collection of these data is generally beyond the budget of individual researchers and the integration and sharing of ecological data and associated infrastructure is becoming more common. However, user groups differ in their expectations, standards of performance, and desired outputs from research investment, and accommodating the motivations and fears of potential users from the outset may lead to higher levels of participation. Here we report upon a study of the Australian ornithology community, which was instigated to better understand perceptions around participation in nationally coordinated research infrastructure for detecting and tracking the movement of birds. The community was surveyed through a questionnaire and individuals were asked to score their motivations and fears around participation. Principal Components Analysis was used to reduce the dimensionality of the data and identify groups of questions where respondents behaved similarly. Linear regressions and model selection were then applied to the principal components to determine how career stage, employment role, and years of biotelemetry experience affected the respondent's motivations and fears for participation. The analysis showed that across all sectors (academic, government, NGO) there was strong motivation to participate and belief that national shared biotelemetry infrastructure would facilitate bird management and conservation. However, results did show that a cross-sector cohort of the Australian ornithology community were keen and ready to progress collaborative infrastructure for tracking birds, and measures including data-sharing agreements could increase participation. It also informed that securing initial funding would be a significant challenge, and a better option to proceed may be for independent groups to coordinate through existing database infrastructure to form the foundation from which a national network could grow.


Assuntos
Comportamento Animal/fisiologia , Medo/psicologia , Motivação/fisiologia , Pesquisadores/psicologia , Adolescente , Adulto , Animais , Austrália , Biodiversidade , Aves/fisiologia , Feminino , Humanos , Colaboração Intersetorial , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Comportamento Social , Inquéritos e Questionários , Adulto Jovem
13.
Mar Environ Res ; 160: 105048, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907741

RESUMO

The thermal response of the amphipod Sunamphitoe parmerong was contrasted between unacclimated 'wild' and acclimated populations. Brooding females were allocated to 17 °C or 23 °C treatments and their progeny developed to adulthood at the same temperature. Tolerance to acute thermal challenge (26-36 °C) was determined. The 17 °C and 23 °C acclimated S. parmerong had a 0.45 and 0.64 risk of death compared to the unacclimated individuals. The upper lethal temperature (LT50) was 27.4 °C for the unacclimated group and 29.6 °C and 30.4 °C for the 17 °C and 23 °C acclimated groups, respectively. Acclimation shifted their LT50 by 2.2 °C and 3 °C, respectively. The wild population exhibited high variability in thermal tolerance, potentially due to their environmental history and greater diversity of genotypes. After acclimation S. parmerong had decreased variability in thermal tolerance and that of the 23 °C group shifted by 1 °C compared with the 17 °C group. These results indicate developmental phenotypic plasticity or differential survival of resilient progeny as potential mechanisms to facilitate persistence in a warming ocean.


Assuntos
Aclimatação , Adaptação Fisiológica , Anfípodes , Aquecimento Global , Anfípodes/fisiologia , Animais , Feminino , Temperatura
14.
Cell Death Dis ; 10(9): 631, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31431617

RESUMO

Prostate cancer is the second most common cancer in men, for which there are no reliable biomarkers or targeted therapies. Here we demonstrate that elevated levels of Δ133TP53ß isoform characterize prostate cancers with immune cell infiltration, particularly T cells and CD163+ macrophages. These cancers are associated with shorter progression-free survival, Gleason scores ≥ 7, and an immunosuppressive environment defined by a higher proportion of PD-1, PD-L1 and colony-stimulating factor 1 receptor (CSF1R) positive cells. Consistent with this, RNA-seq of tumours showed enrichment for pathways associated with immune signalling and cell migration. We further show a role for hypoxia and wild-type p53 in upregulating Δ133TP53 levels. Finally, AUC analysis showed that Δ133TP53ß expression level alone predicted aggressive disease with 88% accuracy. Our data identify Δ133TP53ß as a highly accurate prognostic factor for aggressive prostate cancer.


Assuntos
Neoplasias da Próstata/imunologia , Proteína Supressora de Tumor p53/imunologia , Células A549 , Biomarcadores Tumorais/imunologia , Linhagem Celular Tumoral , Humanos , Células MCF-7 , Macrófagos/imunologia , Masculino , Células PC-3 , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Isoformas de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Linfócitos T/imunologia , Microambiente Tumoral/imunologia , Proteína Supressora de Tumor p53/genética
15.
Conserv Biol ; 33(6): 1426-1437, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30963642

RESUMO

The optimal design of reserve networks and fisheries closures depends on species occurrence information and knowledge of how anthropogenic impacts interact with the species concerned. However, challenges in surveying mobile and cryptic species over adequate spatial and temporal scales can mask the importance of particular habitats, leading to uncertainty about which areas to protect to optimize conservation efforts. We investigated how telemetry-derived locations can help guide the scale and timing of fisheries closures with the aim of reducing threatened species bycatch. Forty juvenile speartooth sharks (Glyphis glyphis) were monitored over 22 months with implanted acoustic transmitters and an array of hydrophone receivers. Using the decision-support tool Marxan, we formulated a permanent fisheries closure that prioritized areas used more frequently by tagged sharks and considered areas perceived as having high value to fisheries. To explore how the size of the permanent closure compared with an alternative set of time-area closures (i.e., where different areas were closed to fishing at different times of year), we used a cluster analysis to group months that had similar arrangements of selected planning units (informed by shark movements during that month) into 2 time-area closures. Sharks were consistent in their timing and direction of migratory movements, but the number of tagged sharks made a big difference in the placement of the permanent closure; 30 individuals were needed to capture behavioral heterogeneity. The dry-season (May-January) and wet-season (February-April) time-area closures opened 20% and 25% more planning units to fishing, respectively, compared with the permanent closure with boundaries fixed in space and time. Our results show that telemetry has the potential to inform and improve spatial management of mobile species and that the temporal component of tracking data can be incorporated into prioritizations to reduce possible impacts of spatial closures on established fisheries.


Uso de Información de Movimiento Basada en Individuos para Identificar las Prioridades de Conservación Espacial para las Especies Móviles Resumen El diseño óptimo de redes de reservas y los cierres de pesquerías depende de la información sobre la presencia de especies y del conocimiento sobre cómo los impactos antropogénicos interactúan con las especies afectadas. Sin embargo, las dificultades que existen al monitorear especies móviles y crípticas en escalas espaciales y temporales adecuadas pueden enmascarar la importancia de los hábitats particulares, lo que resulta en incertidumbre con respecto a cuáles áreas proteger para optimizar los esfuerzos de conservación. Investigamos cómo las ubicaciones derivadas de la telemetría pueden ayudar a guiar la escala y el momento justo del cierre de las pesquerías con el objetivo de reducir la captura accesoria de especies amenazadas. Se monitorearon 40 tiburones lanza juveniles (Glyphis glyphis) durante 22 meses con transmisores acústicos implantados y una selección de receptores hidrofónicos. Con la herramienta de apoyo para la toma de decisiones Marxan, formulamos un cierre de pesquerías permanente que priorizó las áreas usadas con frecuencia por los tiburones marcados y que consideraba a las áreas percibidas como altamente valiosas para las pesquerías. Para explorar cómo el tamaño del cierre permanente se comparaba con un conjunto de cierres con áreas y tiempos alternativos (es decir, donde las áreas se cerraron a la pesca en diferentes momentos del año) usamos un análisis de clúster para agrupar los meses que tuvieron arreglos similares a las unidades de planeación seleccionadas (informadas por el movimiento de los tiburones durante ese mes) en dos cierres de tiempo-área. Los tiburones fueron consistentes en el tiempo y dirección de sus movimientos migratorios, pero el número de tiburones marcados generó una gran diferencia en la ubicación del cierre permanente; se necesitaron 30 individuos para capturar la heterogeneidad del comportamiento. Los cierres de tiempo-área de la temporada de secas (mayo - enero) y la de lluvias (febrero - abril) abrieron a la pesca un 20% y 25% más de unidades de planeación, respectivamente, en comparación con el cierre permanente con barreras fijas en el tiempo y el espacio. Nuestros resultados muestran que la telemetría tiene el potencial para informar y mejorar el manejo espacial de las especies móviles y que el componente temporal de los datos de rastreo puede ser incorporado a las priorizaciones para reducir los posibles impactos del manejo sobre las pesquerías establecidas.


Assuntos
Conservação dos Recursos Naturais , Tubarões , Animais , Ecossistema , Espécies em Perigo de Extinção , Pesqueiros
16.
Oecologia ; 189(4): 891-904, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30868373

RESUMO

Body size and age are crucial factors influencing reproductive capacity and success. As females grow, their reproductive investment and success often increase due to improved overall physiological condition and experience gained through successive reproductive events. While much of this work has been conducted on birds and mammals, surprisingly little is known on how body size affects nesting decisions in other long-lived vertebrates. We monitored the movements and nesting behaviour of 57 wild female estuarine crocodiles Crocodylus porosus over a 10-year period (and across consecutive nesting seasons) using externally mounted satellite tags, implanted acoustic transmitters and a network of submerged acoustic receivers. Applying Hidden Markov models to the telemetry-derived location data revealed that female nesting behaviours could be split into three distinct states: (i) ranging movements within home ranges and at nesting sites; (ii) migrations to and from nesting sites; (iii) and nesting/nest guarding. We found that during migration events, larger females migrated further and remained away from dry season territories for longer periods than smaller individuals. Furthermore, not only were migratory movements stimulated by increases in rainfall, larger females migrated to nest sites at lower rainfall thresholds than smaller females. We provide some of the first evidence of body size influencing nesting decisions in an ectothermic vertebrate, with shifts likely resulting from an increased willingness to invest in nest protection among larger and more experienced females.


Assuntos
Jacarés e Crocodilos , Comportamento de Nidação , Animais , Feminino , Comportamento de Retorno ao Território Vital , Reprodução , Estações do Ano
17.
Trends Ecol Evol ; 34(2): 95-98, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30573193

RESUMO

A request for raw data from the corresponding authors of 771 animal biotelemetry-focused manuscripts, published between 1995 and 2015, highlighted a difference in data sharing practices across researcher career levels. Responses were positive in only 11% of requests made to corresponding authors (CAs) that were senior researchers, while 72% of responses were positive when CAs were early career researchers (ECRs), demonstrating that the majority of senior researchers perceived little benefit from the public data archiving of their published research, while they often remain the data custodian.


Assuntos
Disseminação de Informação , Pesquisadores/estatística & dados numéricos , Fatores Etários , Humanos
18.
Oncotarget ; 9(49): 29146-29161, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-30018742

RESUMO

The TP53 family consists of three sets of transcription factor genes, TP53, TP63 and TP73, each of which expresses multiple RNA variants and protein isoforms. Of these, TP53 is mutated in 25-30% of breast cancers. How TP53 mutations affect the interaction of TP53 family members and their isoforms in breast cancer is unknown. To investigate this, 3 independent breast cancer cohorts were stratified into 4 groups based on oestrogen receptor (ER) and TP53 mutation status. Using bioinformatic methodologies, principal signalling pathways associated with the expression of TP53 family members were identified. Results show an enrichment of IFN-γ signalling associated with TP63 RNA in wild type TP53 (wtTP53), ER negative (ER-) tumours and with Δ133TP53 RNA in mutant TP53 (mTP53) ER positive (ER+) tumours. Moreover, tumours with low IFN-γ signalling were associated with significantly poorer patient outcome. The predicted changes in expression of a subset of RNAs involved in IFN-γ signalling were confirmed in vitro. Our data show that different members of the TP53 family can drive transcription of genes involved in IFN-γ signalling in different breast cancer subgroups.

19.
Sci Rep ; 8(1): 3717, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29487384

RESUMO

Acoustic telemetry is a principle tool for observing aquatic animals, but coverage over large spatial scales remains a challenge. To resolve this, Australia has implemented the Integrated Marine Observing System's Animal Tracking Facility which comprises a continental-scale hydrophone array and coordinated data repository. This national acoustic network connects localized projects, enabling simultaneous monitoring of multiple species over scales ranging from 100 s of meters to 1000 s of kilometers. There is a need to evaluate the utility of this national network in monitoring animal movement ecology, and to identify the spatial scales that the network effectively operates over. Cluster analyses assessed movements and residency of 2181 individuals from 92 species, and identified four functional movement classes apparent only through aggregating data across the entire national network. These functional movement classes described movement metrics of individuals rather than species, and highlighted the plasticity of movement patterns across and within populations and species. Network analyses assessed the utility and redundancy of each component of the national network, revealing multiple spatial scales of connectivity influenced by the geographic positioning of acoustic receivers. We demonstrate the significance of this nationally coordinated network of receivers to better reveal intra-specific differences in movement profiles and discuss implications for effective management.


Assuntos
Distribuição Animal/fisiologia , Escamas de Animais/fisiologia , Animais , Análise por Conglomerados , Ecologia , Ecossistema
20.
Nat Commun ; 9(1): 254, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29343721

RESUMO

∆122p53 mice (a model of ∆133p53 isoform) are tumour-prone, have extensive inflammation and elevated serum IL-6. To investigate the role of IL-6 we crossed ∆122p53 mice with IL-6 null mice. Here we show that loss of IL-6 reduced JAK-STAT signalling, tumour incidence and metastasis. We also show that ∆122p53 activates RhoA-ROCK signalling leading to tumour cell invasion, which is IL-6-dependent and can be reduced by inhibition of JAK-STAT and RhoA-ROCK pathways. Similarly, we show that Δ133p53 activates these pathways, resulting in invasive and migratory phenotypes in colorectal cancer cells. Gene expression analysis of colorectal tumours showed enrichment of GPCR signalling associated with ∆133TP53 mRNA. Patients with elevated ∆133TP53 mRNA levels had a shorter disease-free survival. Our results suggest that ∆133p53 promotes tumour invasion by activation of the JAK-STAT and RhoA-ROCK pathways, and that patients whose tumours have high ∆133TP53 may benefit from therapies targeting these pathways.


Assuntos
Neoplasias Colorretais/metabolismo , Interleucina-6/metabolismo , Janus Quinases/metabolismo , Fatores de Transcrição STAT/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Feminino , Células HCT116 , Humanos , Masculino , Camundongos , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Isoformas de Proteínas , RNA Mensageiro/metabolismo , Transdução de Sinais
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