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1.
Mol Ecol ; 33(3): e17230, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38078558

RESUMO

Urbanization is a persistent and widespread driver of global environmental change, potentially shaping evolutionary processes due to genetic drift and reduced gene flow in cities induced by habitat fragmentation and small population sizes. We tested this prediction for the eastern grey squirrel (Sciurus carolinensis), a common and conspicuous forest-dwelling rodent, by obtaining 44K SNPs using reduced representation sequencing (ddRAD) for 403 individuals sampled across the species' native range in eastern North America. We observed moderate levels of genetic diversity, low levels of inbreeding, and only a modest signal of isolation-by-distance. Clustering and migration analyses show that estimated levels of migration and genetic connectivity were higher than expected across cities and forested areas, specifically within the eastern portion of the species' range dominated by urbanization, and genetic connectivity was less than expected within the western range where the landscape is fragmented by agriculture. Landscape genetic methods revealed greater gene flow among individual squirrels in forested regions, which likely provide abundant food and shelter for squirrels. Although gene flow appears to be higher in areas with more tree cover, only slight discontinuities in gene flow suggest eastern grey squirrels have maintained connected populations across urban areas in all but the most heavily fragmented agricultural landscapes. Our results suggest urbanization shapes biological evolution in wildlife species depending strongly on the composition and habitability of the landscape matrix surrounding urban areas.


Assuntos
Animais Selvagens , Metagenômica , Animais , Humanos , População Urbana , Ecossistema , Sciuridae/genética
2.
Biol Lett ; 19(3): 20220555, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36987612

RESUMO

Diel patterns in foraging activity are dictated by a combination of abiotic, biotic and endogenous limits. Understanding these limits is important for insects because ectotherm taxa will respond more pronouncedly to ongoing climatic change, potentially affecting crucial ecosystem services. We leverage an experimental macrocosm, the Montreal Insectarium Grand Vivarium, to test the importance of endogenous mechanisms in determining temporal patterns in foraging activity of butterflies. Specifically, we assessed the degree of temporal niche partitioning among 24 butterfly species originating from the Earth's tropics within controlled environmental conditions. We found strong niche overlap, with the frequency of foraging events peaking around solar noon for 96% of the species assessed. Our models suggest that this result was not due to the extent of cloud cover, which affects radiational heating and thus limits body temperature in butterflies. Together, these findings suggest that an endogenous mechanism evolved to regulate the timing of butterfly foraging activity within suitable environmental conditions. Understanding similar mechanisms will be crucial to forecast the effects of climate change on insects, and thus on the many ecosystem services they provide.


Assuntos
Borboletas , Ecossistema , Animais , Borboletas/fisiologia , Mudança Climática
3.
Curr Biol ; 32(16): R871-R873, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35998593

RESUMO

In the internet era, the digital architecture that keeps us connected and informed may also amplify the spread of misinformation. This problem is gaining global attention, as evidence accumulates that misinformation may interfere with democratic processes and undermine collective responses to environmental and health crises1,2. In an increasingly polluted information ecosystem, understanding the factors underlying the generation and spread of misinformation is becoming a pressing scientific and societal challenge3. Here, we studied the global spread of (mis-)information on spiders using a high-resolution global database of online newspaper articles on spider-human interactions, covering stories of spider-human encounters and biting events published from 2010-20204. We found that 47% of articles contained errors and 43% were sensationalist. Moreover, we show that the flow of spider-related news occurs within a highly interconnected global network and provide evidence that sensationalism is a key factor underlying the spread of misinformation.


Assuntos
Mídias Sociais , Aranhas , Animais , Comunicação , Ecossistema , Humanos , Aranhas/fisiologia
4.
Sci Data ; 9(1): 109, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35347145

RESUMO

Mass media plays an important role in the construction and circulation of risk perception associated with animals. Widely feared groups such as spiders frequently end up in the spotlight of traditional and social media. We compiled an expert-curated global database on the online newspaper coverage of human-spider encounters over the past ten years (2010-2020). This database includes information about the location of each human-spider encounter reported in the news article and a quantitative characterisation of the content-location, presence of photographs of spiders and bites, number and type of errors, consultation of experts, and a subjective assessment of sensationalism. In total, we collected 5348 unique news articles from 81 countries in 40 languages. The database refers to 211 identified and unidentified spider species and 2644 unique human-spider encounters (1121 bites and 147 as deadly bites). To facilitate data reuse, we explain the main caveats that need to be made when analysing this database and discuss research ideas and questions that can be explored with it.


Assuntos
Picada de Aranha , Venenos de Aranha , Aranhas , Animais , Bases de Dados Factuais , Humanos , Idioma , Jornais como Assunto
5.
Insects ; 12(10)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34680690

RESUMO

In general, insects and arthropods polarizing: they either fascinate people, disgust people, or both, and they generate lots of questions. Museums are perceived as reliable sources of information and, as such, a go-to destination for the public to receive answers. Since its opening in 1990, the Montreal Insectarium has offered an entomological information service, allowing the public to send questions, photographs, and specimens for identification. All requests are answered by entomologists. Spatiotemporal variations in taxonomic, geographic, and thematic profiles of the 4163 requests received in 2010-2011 and 2017-2018 were analyzed. Requests came from 35 countries, and most of those requests came from Canada. The majority of requests were identification requests. Representing 25% of identification requests, the five most frequent species were the eastern dobsonfly Corydalus cornutus, the masked hunter Reduvius personatus, the giant water bug Lethocerus americanus, the western conifer-seed bug Leptoglossus occidentalis, and the Japanese beetle Popillia japonica. A comparison with the data from the citizen science platform iNaturalist shows that the EIS can be a valuable tool for invasive species detection. Frequent subjects included school projects, entomophagy (eating insects), and wasp and bee nests. Finally, we discuss the role of entomologists in providing scientific information but also in addressing common concerns regarding cohabitation with arthropods.

8.
Can J Psychiatry ; 63(3): 182-196, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29513631

RESUMO

This paper has been substantially revised by the Canadian Psychiatric Association's Research Committee and approved for republication by the CPA's Board of Directors on May 3, 2017. The original policy paper1 was developed by the Scientific and Research Affairs Standing Committee and approved by the Board of Directors on November 10, 2008.


Assuntos
Guias como Assunto/normas , Meios de Comunicação de Massa/normas , Psiquiatria/normas , Sociedades Médicas/normas , Suicídio , Canadá , Humanos
10.
Can J Public Health ; 107(3): e330-e332, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27763851

RESUMO

Media reporting on suicide may have harmful and/or protective effects on deaths by suicide, depending on the nature of the coverage. Canada's first forum on this important issue was held in Toronto on November 6, 2015. Participating in the forum were public health policy-makers, mental health and suicide prevention experts and senior media representatives. This commentary summarizes the content of the forum and highlights the need for ongoing collaboration between suicide prevention experts and media professionals aimed at safe and respectful reporting that maintains the public's need to be informed.


Assuntos
Meios de Comunicação de Massa , Prevenção do Suicídio , Canadá , Congressos como Assunto , Humanos
11.
Paediatr Child Health ; 21(5): 237-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27441013
13.
BMC Med Ethics ; 14: 6, 2013 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-23402260

RESUMO

BACKGROUND: In 2009, Dr. Paolo Zamboni proposed chronic cerebrospinal venous insufficiency (CCSVI) as a possible cause of multiple sclerosis (MS). Although his theory and the associated treatment ("liberation therapy") received little more than passing interest in the international scientific and medical communities, his ideas became the source of tremendous public and political tension in Canada. The story moved rapidly from mainstream media to social networking sites. CCSVI and liberation therapy swiftly garnered support among patients and triggered remarkable and relentless advocacy efforts. Policy makers have responded in a variety of ways to the public's call for action. DISCUSSION: We present three different perspectives on this evolving story, that of a health journalist who played a key role in the media coverage of this issue, that of a health law and policy scholar who has closely observed the unfolding public policy developments across the country, and that of a medical ethicist who sits on an expert panel convened by the MS Society of Canada and the Canadian Institutes of Health Research to assess the evidence as it emerges. SUMMARY: This story raises important questions about resource allocation and priority setting in scientific research and science policy. The growing power of social media represents a new level of citizen engagement and advocacy, and emphasizes the importance of open debate about the basis on which such policy choices are made. It also highlights the different ways evidence may be understood, valued and utilized by various stakeholders and further emphasizes calls to improve science communication so as to support balanced and informed decision-making.


Assuntos
Medicina Baseada em Evidências , Alocação de Recursos para a Atenção à Saúde , Política de Saúde , Esclerose Múltipla/etiologia , Esclerose Múltipla/terapia , Defesa do Paciente , Formulação de Políticas , Política , Mídias Sociais , Insuficiência Venosa/complicações , Angioplastia com Balão/efeitos adversos , Encéfalo/irrigação sanguínea , Canadá , Ensaios Clínicos como Assunto/economia , Ensaios Clínicos como Assunto/ética , Tomada de Decisões , Humanos , Apoio à Pesquisa como Assunto , Saskatchewan , Coluna Vertebral/irrigação sanguínea , Stents/efeitos adversos
15.
J Cell Sci ; 120(Pt 4): 702-11, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17264146

RESUMO

Orderly progression through the eukaryotic cell cycle is a complex process involving both regulation of cyclin dependent kinase activity and control of specific substrate-Cdk interactions. In Saccharomyces cerevisiae, the mitotic cyclin Clb2 has a central role in regulating the onset of anaphase and in maintaining the cellular shape of the bud by inhibiting growth polarization induced in G1. However, how Clb2 and the partially redundant cyclin Clb1 confer specificity to Cdk1 in these processes still remains unclear. Here, we show that Clb2 mutants impaired in nuclear import or export are differentially affected for subsets of Clb2 functions while remaining fully functional for others. Our data support a direct role of the cytoplasmic pool of Clb1,2-Cdk1 in terminating cytoskeleton and growth polarization, independently of G1 cyclin transcriptional regulation. By contrast, the nuclear form of the cyclin is required for timely initiation of anaphase. Clb2 localization influences its stage-specific degradation as well. We report that Clb2 trapped in the cytoplasm is stabilized during anaphase but not at the time of mitotic exit. Altogether, our results demonstrate that the subcellular localization of the mitotic cyclin Clb2 is one of the key determinants of its biological function.


Assuntos
Compartimento Celular , Ciclina B/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Ciclina B/genética , Proteínas Fúngicas/genética , Proteínas de Fluorescência Verde/metabolismo , Mutação , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
16.
Proc Natl Acad Sci U S A ; 103(31): 11647-52, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16868079

RESUMO

The green lineage is reportedly 1,500 million years old, evolving shortly after the endosymbiosis event that gave rise to early photosynthetic eukaryotes. In this study, we unveil the complete genome sequence of an ancient member of this lineage, the unicellular green alga Ostreococcus tauri (Prasinophyceae). This cosmopolitan marine primary producer is the world's smallest free-living eukaryote known to date. Features likely reflecting optimization of environmentally relevant pathways, including resource acquisition, unusual photosynthesis apparatus, and genes potentially involved in C(4) photosynthesis, were observed, as was downsizing of many gene families. Overall, the 12.56-Mb nuclear genome has an extremely high gene density, in part because of extensive reduction of intergenic regions and other forms of compaction such as gene fusion. However, the genome is structurally complex. It exhibits previously unobserved levels of heterogeneity for a eukaryote. Two chromosomes differ structurally from the other eighteen. Both have a significantly biased G+C content, and, remarkably, they contain the majority of transposable elements. Many chromosome 2 genes also have unique codon usage and splicing, but phylogenetic analysis and composition do not support alien gene origin. In contrast, most chromosome 19 genes show no similarity to green lineage genes and a large number of them are specialized in cell surface processes. Taken together, the complete genome sequence, unusual features, and downsized gene families, make O. tauri an ideal model system for research on eukaryotic genome evolution, including chromosome specialization and green lineage ancestry.


Assuntos
Clorófitas/genética , Células Eucarióticas , Genoma , Animais , Cromossomos , Evolução Molecular , Dados de Sequência Molecular , Análise de Sequência de DNA
17.
Int J Health Serv ; 35(3): 603-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16119578

RESUMO

Gary Schwitzer, former medical correspondent at CNN and now a professor of journalism, listed "10 troublesome trends in TV health news," making the important point that most people today get their health information from the media, and from TV in particular. In this article, the author presents Schwitzer's list and expands it with 10 more troublesome trends. Good health reporting should provide a straightforward, balanced, comprehensible summary of health issues that provides context to information-hungry consumers; it should rarely be sensational, but always skeptical. And there should be a lot more of it.


Assuntos
Jornalismo Médico/normas , Meios de Comunicação de Massa/normas , Editoração/normas , Televisão/normas , Humanos , Política , Viés de Publicação , Reino Unido , Estados Unidos
18.
Dev Biol ; 285(1): 200-10, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16081061

RESUMO

In vertebrates, enhanced translation of mRNAs in oocytes and early embryos entering M-phase is thought to occur through polyadenylation, involving binding, hyperphosphorylation and proteolytic degradation of Aurora-activated CPEB. In starfish, an unknown component of the oocyte nucleus is required for cyclin B synthesis following the release of G2/prophase block by hormonal stimulation. We have found that CPEB cannot be hyperphosphorylated following hormonal stimulation in starfish oocytes from which the nucleus has been removed. Activation of Aurora kinase, known to interact with protein phosphatase 1 and its specific inhibitor Inh-2, is also prevented. The microinjection of Inh-2 restores Aurora activation, CPEB hyperphosphorylation and cyclin B translation in enucleated oocytes. Nevertheless, we provide evidence that CPEB is in fact hyperphosphorylated by cdc2, without apparent involvement of Aurora or MAP kinase, and that cyclin B synthesis can be stimulated without previous degradation of phosphorylated CPEB. Thus, the regulation of cyclin B synthesis necessary for progression through meiosis can be explained by an equilibrium between CPEB phosphorylation and dephosphorylation, and both aspects of this control may rely on the sole activation of Cdc2 and subsequent nuclear breakdown.


Assuntos
Ciclina B/genética , Membrana Nuclear/metabolismo , Oócitos/metabolismo , Fosfoproteínas Fosfatases/antagonistas & inibidores , Estrelas-do-Mar/metabolismo , Animais , Inibidores Enzimáticos/metabolismo , Feminino , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Oócitos/citologia , Fosforilação , Biossíntese de Proteínas , Proteína Fosfatase 1 , Estrelas-do-Mar/citologia , Estrelas-do-Mar/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/genética , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo
19.
Dev Biol ; 282(1): 192-206, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15936340

RESUMO

Activation and role of mitogen-activated protein (MAP) kinase (MAPK) during mitosis are still matters of controversy in early embryos. We report here that an ERK-like protein is present and highly phosphorylated in unfertilized sea urchin eggs. This MAPK becomes dephosphorylated after fertilization and a small pool of it is transiently reactivated during mitosis. The phosphorylated ERK-like protein is localized to the nuclear region and then to the mitotic poles and the mitotic spindle. Treatment of eggs after fertilization with two different MEK inhibitors, PD 98059 and U0126, at low concentrations capable to selectively induce dephosphorylation of this ERK-like protein, or expression of a dominant-negative MEK1/2, perturbed mitotic progression. Our results suggest that an ERK-like cascade is part of a control mechanism that regulates mitotic spindle formation and the attachment of chromosomes to the spindle during the first mitosis of the sea urchin embryo.


Assuntos
Fertilização/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mitose/fisiologia , Óvulo/fisiologia , Ouriços-do-Mar/embriologia , Transdução de Sinais/fisiologia , Fuso Acromático/fisiologia , Animais , Western Blotting , Butadienos/farmacologia , Ativação Enzimática/fisiologia , Flavonoides/farmacologia , Histocitoquímica , Microscopia de Vídeo , Mitose/efeitos dos fármacos , Nitrilas/farmacologia , Fosforilação/efeitos dos fármacos
20.
Mol Reprod Dev ; 67(3): 366-83, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14735498

RESUMO

The default fate for eggs from many species is death by apoptosis and thus, successful fertilization depends upon suppression of the maternal death program. Little is known about the molecular triggers which activate this process or how the fertilization signal suppresses the default maternal apoptotic pathway. The MAP kinase (MAPK) family member, ERK, plays a universal and critical role in several stages of oocyte meiotic maturation, and fertilization results in ERK inactivation. In somatic cells, ERK and other MAPK family members, p38 and JNK, provide opposing signals to regulate apoptosis, however, it is not known whether MAPKs play a regulatory role in egg apoptosis, nor whether suppression of apoptosis by fertilization is mediated by MAPK activity. Here we demonstrate that MAPKs are involved in starfish egg apoptosis and we investigate the relationship between the fertilization induced signaling pathway and MAPK activation. ERK is active in post-meiotic eggs just until apoptosis onset and then p38, JNK and a third kinase are activated, and remain active through execution. Sequential activation of ERK and p38 is necessary for apoptosis, and newly synthesized proteins are required both upstream of ERK and downstream of p38 for activation of the full apoptotic program. Fertilization causes a dramatic rise in intracellular Ca2+, and we report that Ca2+ provides a necessary and sufficient pro-survival signal. The Ca2+ pathway following fertilization of both young and aged eggs causes ERK to be rapidly inactivated, but fertilization cannot rescue aged eggs from death, indicating that ERK inactivation is not sufficient to suppress apoptosis.


Assuntos
Apoptose/fisiologia , Cálcio/fisiologia , Fertilização/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Óvulo/fisiologia , Animais , Feminino , Transdução de Sinais/fisiologia , Estrelas-do-Mar/fisiologia , Fatores de Tempo , Proteínas Quinases p38 Ativadas por Mitógeno
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