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1.
Ecol Lett ; 24(6): 1178-1186, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33750013

RESUMO

For many species, climate change leads to range shifts that are detectable, but often insufficient to track historical climatic conditions. These lags of species range shifts behind climatic conditions are often coined "climatic debts", but the demographic costs entailed by the word "debt" have not been demonstrated. Here, we used opportunistic distribution data for c. 4000 European plant species to estimate the temporal shifts in climatic conditions experienced by these species and their occupancy trends, over the last 65 years. The resulting negative relationship observed between these two variables provides the first piece of evidence that European plants are already paying a climatic debt in Alpine, Atlantic and Boreal regions. In contrast, plants appear to benefit from a surprising "climatic bonus" in the Mediterranean. We also find that among multiple pressures faced by plants, climate change is now on par with other known drivers of occupancy trends, including eutrophication and urbanisation.


Assuntos
Mudança Climática , Ecossistema , Plantas , Urbanização
2.
J Adolesc ; 79: 91-102, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31926450

RESUMO

INTRODUCTION: Adolescents spend an increasing amount of time using digital media, but gender differences in their use and in associations with psychological well-being are unclear. METHOD: We drew from three large, representative surveys of 13- to 18-year-old adolescents in the U.S. and UK (total N = 221,096) examining digital media use in hours per day and several measures of psychological well-being separately in each of the three datasets. RESULTS: Adolescent girls spent more time on smartphones, social media, texting, general computer use, and online, and boys spent more time gaming and on electronic devices in general. Associations between moderate or heavy digital media use and low psychological well-being/mental health issues were generally larger for girls than for boys. Light users of digital media were slightly higher in well-being than non-users, with larger differences among boys. Among both genders, heavy users of digital media were often twice as likely as low users to be low in well-being or have mental health issues, including risk factors for suicide. CONCLUSIONS: Associations between heavy digital media use and low psychological well-being are larger for adolescent girls than boys.


Assuntos
Comportamento do Adolescente/psicologia , Smartphone/estatística & dados numéricos , Mídias Sociais/estatística & dados numéricos , Jogos de Vídeo/estatística & dados numéricos , Adolescente , Feminino , Humanos , Masculino , Fatores de Risco , Distribuição por Sexo , Fatores Sexuais , Ideação Suicida , Inquéritos e Questionários , Jogos de Vídeo/psicologia
3.
Biol Lett ; 15(7): 20190280, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31288688

RESUMO

Latitudinal and altitudinal range shifts in response to climate change have been reported for numerous animal species, especially those with high dispersal capacities. In plants, the impact of climate change on species distribution or community composition has been documented mainly over long periods (decades) and in specific habitats, often forests. Here, we broaden the results of such long-term, focused studies by examining climate-driven changes in plant community composition over a large area (France) encompassing multiple habitat types and over a short period (2009-2017). To this end, we measured mean community thermal preference, calculated as the community-weighted mean of the Ellenberg temperature indicator value, using data from a standardized participatory monitoring scheme. We report a rapid increase in the mean thermal preference of plant communities at national and regional scales, which we relate to climate change. This reshuffling of plant community composition corresponds to a relative increase in the abundance of warm- versus cold-adapted species. However, support for this trend was weaker when considering only the common species, including common annuals. Our results thus suggest for the first time that the response of plant communities to climate change involves subtle changes affecting all species rare and common, which can nonetheless be detected over short time periods. Whether such changes are sufficient to cope with the current climate warming remains to be ascertained.


Assuntos
Mudança Climática , Plantas , Animais , Ecossistema , França , Temperatura
4.
J Therm Biol ; 79: 149-154, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30612675

RESUMO

Mouse vivaria are typically maintained at an ambient temperature (Ta) of 20-26 °C which is comfortable for human researchers. However, as this Ta is well below the mouse thermoneutral zone (TNZ) of 30-32 °C, typical vivarium temperatures result in cold stress for mice. Recently, a cage has been developed that provides variable cage floor heating, allowing mice to behaviorally regulate body temperature through thermotaxis. A hand warmer provides supplemental heat, elevating cage floor surface temperature for 13 + hours up to 30 °C. This provides a heated surface for the entirety of the light phase. Here, we test the ability of these local heat sources to remove physiological signs of cold stress in mice housed at room temperature by analyzing heart rate (HR), activity, and body temperature in three experimental conditions: 23 °C, 23 °C + heated surface, or 30 °C. The location of C57Bl/6 J mice within the cage was recorded using an infrared camera. In the presence of supplemental heat at a Ta of 23 °C, mice resided atop of the area of the heated surface 85 ±â€¯3% of the 12-h light phase, as compared to 7 ±â€¯2% in the absence of supplemental heat. Further, addition of supplemental heat lowered light phase HR and activity to that seen at a Ta of 30 °C. These results indicate that provision of a local heat source is successful in reducing cold-induced tachycardia in mice housed at typical vivarium temperatures without increasing the ambient temperature of the entire laboratory and subjecting researchers to heat stress.


Assuntos
Temperatura Baixa/efeitos adversos , Calefação/instrumentação , Abrigo para Animais/normas , Estresse Fisiológico , Taquicardia/prevenção & controle , Animais , Calefação/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Taquicardia/etiologia , Taquicardia/terapia
6.
BMJ Case Rep ; 17(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839415

RESUMO

Ventricular tachycardia (VT) is a rare but potentially fatal complication in pregnancy. We present a case of a pregnant woman with cardiomyopathy due to frequent premature ventricular complexes (PVCs) and VT originating from the left ventricular outflow tract. After presenting late in the third trimester, the decision was made to deliver the fetus after 4 days of medication titration due to continued sustained episodes of VT. After delivery, the patient continued to have frequent PVCs and VT several months after discharge, and she ultimately underwent a PVC ablation with dramatic reduction in PVC burden and improvement in cardiomyopathy. Multidisciplinary planning with a pregnancy heart team led to appropriate contingency planning and a successful delivery. This case highlights how multidisciplinary management is best practice in pregnancy complicated by VT and the need for better diagnostic guidelines for PVC-induced cardiomyopathy in the setting of pregnancy.


Assuntos
Cardiomiopatias , Complicações Cardiovasculares na Gravidez , Taquicardia Ventricular , Complexos Ventriculares Prematuros , Humanos , Feminino , Gravidez , Taquicardia Ventricular/terapia , Taquicardia Ventricular/etiologia , Cardiomiopatias/terapia , Cardiomiopatias/complicações , Complicações Cardiovasculares na Gravidez/terapia , Complicações Cardiovasculares na Gravidez/diagnóstico , Adulto , Complexos Ventriculares Prematuros/terapia , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/etiologia , Período Periparto , Ablação por Cateter , Eletrocardiografia , Antiarrítmicos/uso terapêutico , Antiarrítmicos/administração & dosagem
7.
Cardiovasc Digit Health J ; 4(1): 9-20, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36865583

RESUMO

Cuff-based home blood pressure (BP) devices, which have been the standard for BP monitoring for decades, are limited by physical discomfort, convenience, and their ability to capture BP variability and patterns between intermittent readings. In recent years, cuffless BP devices, which do not require cuff inflation around a limb, have entered the market, offering the promise of continuous beat-to-beat measurement of BP. These devices take advantage of a variety of principles to determine BP, including (1) pulse arrival time, (2) pulse transit time, (3) pulse wave analysis, (4) volume clamping, and (5) applanation tonometry. Because BP is calculated indirectly, these devices require calibration with cuff-based devices at regular intervals. Unfortunately, the pace of regulation of these devices has failed to match the speed of innovation and direct availability to patient consumers. There is an urgent need to develop a consensus on standards by which cuffless BP devices can be tested for accuracy. In this narrative review, we describe the landscape of cuffless BP devices, summarize the current status of validation protocols, and provide recommendations for an ideal validation process for these devices.

8.
Ocul Surf ; 23: 197-200, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653711

RESUMO

PURPOSE: Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). While the ocular surface is considered one of the major SARS-CoV2 transmission routes, the specific cellular tropism of SARS-CoV2 is not fully understood. In the current study, we evaluated the expression and regulation of two SARS-CoV2 viral entry proteins, TMPRSS2 and ACE2, in human ocular epithelial cells and stem cells. METHODS: TMPRSS2 and ACE2 expression in ABCB5-positive limbal stem cells (LSCs) were assessed by RNAseq, flow cytometry and immunohistochemistry. PAX6, TMPRSS2, and ACE2 mRNA expression values were obtained from the GSE135455 and DRA002960 RNA-seq datasets. siRNA-mediated PAX6 knockdown (KD) was performed in limbal and conjunctival epithelial cells. TMPRSS2 and ACE2 expression in the PAX6 KD cells was analyzed by qRT-PCR and Western blot. RESULTS: We found that ABCB5-positive LSCs express high levels of TMPRSS2 and ACE2 compared to ABCB5-negative limbal epithelial cells. Mechanistically, gene knockout and overexpression models revealed that the eye transcription factor PAX6 negatively regulates TMPRSS2 expression. Therefore, low levels of PAX6 in ABCB5-positive LSCs promote TMPRSS2 expression, and high levels of TMPRSS2 and ACE2 expression by LSCs indicate enhanced susceptibility to SARS-CoV2 infection in this stem cell population. CONCLUSIONS: Our study points to a need for COVID-19 testing of LSCs derived from donor corneas before transplantation to patients with limbal stem cell deficiency. Furthermore, our findings suggest that expandable human ABCB5+ LSC cultures might represent a relevant novel model system for studying cellular SARS-CoV2 viral entry mechanisms and evaluating related targeting strategies.


Assuntos
COVID-19 , RNA Viral , Subfamília B de Transportador de Cassetes de Ligação de ATP , Teste para COVID-19 , Humanos , SARS-CoV-2 , Células-Tronco , Proteínas Virais , Internalização do Vírus
9.
Methods Ecol Evol ; 13(7): 1497-1507, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36250156

RESUMO

Aggregated species occurrence and abundance data from disparate sources are increasingly accessible to ecologists for the analysis of temporal trends in biodiversity. However, sampling biases relevant to any given research question are often poorly explored and infrequently reported; this can undermine statistical inference. In other disciplines, it is common for researchers to complete 'risk-of-bias' assessments to expose and document the potential for biases to undermine conclusions. The huge growth in available data, and recent controversies surrounding their use to infer temporal trends, indicate that similar assessments are urgently needed in ecology.We introduce ROBITT, a structured tool for assessing the 'Risk-Of-Bias In studies of Temporal Trends in ecology'. ROBITT has a similar format to its counterparts in other disciplines: it comprises signalling questions designed to elicit information on the potential for bias in key study domains. In answering these, users will define study inferential goal(s) and relevant statistical target populations. This information is used to assess potential sampling biases across domains relevant to the research question (e.g. geography, taxonomy, environment), and how these vary through time. If assessments indicate biases, then users must clearly describe them and/or explain what mitigating action will be taken.Everything that users need to complete a ROBITT assessment is provided: the tool, a guidance document and a worked example. Following other disciplines, the tool and guidance document were developed through a consensus-forming process across experts working in relevant areas of ecology and evidence synthesis.We propose that researchers should be strongly encouraged to include a ROBITT assessment when publishing studies of biodiversity trends, especially when using aggregated data. This will help researchers to structure their thinking, clearly acknowledge potential sampling issues, highlight where expert consultation is required and provide an opportunity to describe data checks that might go unreported. ROBITT will also enable reviewers, editors and readers to establish how well research conclusions are supported given a dataset combined with some analytical approach. In turn, it should strengthen evidence-based policy and practice, reduce differing interpretations of data and provide a clearer picture of the uncertainties associated with our understanding of reality.

10.
Cell Rep ; 40(6): 111166, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35947947

RESUMO

The corneal epithelium is renowned for high regenerative potential, which is dependent on the coordinated function of its diverse progenitor subpopulations. However, the molecular pathways governing corneal epithelial progenitor differentiation are incompletely understood. Here, we identify a highly proliferative limbal epithelial progenitor subpopulation characterized by expression of basal cell adhesion molecule (BCAM) that is capable of holocone formation and corneal epithelial sheet generation. BCAM-positive cells can be found among ABCB5-positive limbal stem cells (LSCs) as well as among ABCB5-negative limbal epithelial cell populations. Mechanistically, we show that BCAM is functionally required for cellular migration and differentiation and that its expression is regulated by the transcription factor p63. In aggregate, our study identifies limbal BCAM expression as a marker of highly proliferative corneal epithelial progenitor cells and defines the role of BCAM as a critical molecular mediator of corneal epithelial differentiation.


Assuntos
Epitélio Corneano , Limbo da Córnea , Diferenciação Celular , Células Cultivadas , Córnea , Células Epiteliais/metabolismo , Limbo da Córnea/metabolismo , Células-Tronco/metabolismo
11.
Emotion ; 18(6): 765-780, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29355336

RESUMO

In nationally representative yearly surveys of United States 8th, 10th, and 12th graders 1991-2016 (N = 1.1 million), psychological well-being (measured by self-esteem, life satisfaction, and happiness) suddenly decreased after 2012. Adolescents who spent more time on electronic communication and screens (e.g., social media, the Internet, texting, gaming) and less time on nonscreen activities (e.g., in-person social interaction, sports/exercise, homework, attending religious services) had lower psychological well-being. Adolescents spending a small amount of time on electronic communication were the happiest. Psychological well-being was lower in years when adolescents spent more time on screens and higher in years when they spent more time on nonscreen activities, with changes in activities generally preceding declines in well-being. Cyclical economic indicators such as unemployment were not significantly correlated with well-being, suggesting that the Great Recession was not the cause of the decrease in psychological well-being, which may instead be at least partially due to the rapid adoption of smartphones and the subsequent shift in adolescents' time use. (PsycINFO Database Record


Assuntos
Internet/estatística & dados numéricos , Psicologia do Adolescente/tendências , Smartphone/estatística & dados numéricos , Adolescente , Feminino , Felicidade , História do Século XXI , Humanos , Internet/história , Relações Interpessoais , Masculino , Satisfação Pessoal , Psicologia do Adolescente/história , Autoimagem , Smartphone/história , Mídias Sociais/estatística & dados numéricos , Envio de Mensagens de Texto/estatística & dados numéricos , Estados Unidos
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