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1.
Curr Res Toxicol ; 6: 100174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841651

RESUMO

Gold complexes can be a useful system in the fight against cancer. Although many studies have been carried out on in vitro 2D cell culture models embryotoxic assays are particularly lacking. Embryotoxicity and DNA damage are critical concerns in drug development. In this study, the effects of a new N-Heterocyclic carbene (NHC)-Au compound (Bromo[1,3-di-4-methoxybenzyl-4,5-bis(4-methoxyphenyl)imidazol-2-ylidene]gold(I)) at different concentrations were explored using multifaceted approach, encompassing 2D cancer cell cultures, in vivo zebrafish and in vitro bovine models, and compared with a consolidated similar complex (Bromo[1,3-diethyl-4,5-bis(4-methoxyphenyl)imidazol-2-ylidene]gold(I)). The results obtained from 2D cancer cell cultures revealed concentration-dependent effects of the gold compounds by estimating the cytotoxicity with MTT assay and cellular damage as indicated by LDH release. Selected concentrations of gold complexes demonstrated no adverse effects on zebrafish embryo development. However, in bovine embryos, these same concentrations led to significant impairments in the early developmental stages, triggering cell apoptosis and reducing blastocyst competence. These findings underscore the importance of evaluating drug effects across different model systems to comprehensively assess their safety and potential impact on embryonic development.

2.
Cells ; 13(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38920627

RESUMO

Preimplantation embryo culture, pivotal in assisted reproductive technology (ART), has lagged in innovation compared to embryo selection advancements. This review examines the persisting gap between in vivo and in vitro embryo development, emphasizing the need for improved culture conditions. While in humans this gap is hardly estimated, animal models, particularly bovines, reveal clear disparities in developmental competence, cryotolerance, pregnancy and live birth rates between in vitro-produced (IVP) and in vivo-derived (IVD) embryos. Molecular analyses unveil distinct differences in morphology, metabolism, and genomic stability, underscoring the need for refining culture conditions for better ART outcomes. To this end, a deeper comprehension of oviduct physiology and embryo transport is crucial for grasping embryo-maternal interactions' mechanisms. Research on autocrine and paracrine factors, and extracellular vesicles in embryo-maternal tract interactions, elucidates vital communication networks for successful implantation and pregnancy. In vitro, confinement, and embryo density are key factors to boost embryo development. Advanced dynamic culture systems mimicking fluid mechanical stimulation in the oviduct, through vibration, tilting, and microfluidic methods, and the use of innovative softer substrates, hold promise for optimizing in vitro embryo development.


Assuntos
Técnicas de Cultura Embrionária , Embrião de Mamíferos , Animais , Humanos , Técnicas de Cultura Embrionária/métodos , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário , Gravidez , Feminino , Blastocisto/citologia , Blastocisto/metabolismo
3.
Cells ; 13(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38786090

RESUMO

The possibility of detecting the developmental competence of individually cultured embryos through analysis of spent media is a major current trend in an ART setting. However, individual embryo culture is detrimental compared with high-density group culture due to the reduced concentration of putative embryotropins. The main aim of this study was to identify an individual culture system that is not detrimental over high-density group culture in the bovine model. Blastocyst rates and competence were investigated in a conventional (GC) group, semi-confined group (MG), and individual culture (MS) in a commercial microwell device. Main findings showed that: (1) individual embryos can be continuously cultured for 7 days in ~70 nL microwells (MS) without detrimental effects compared with the GC and MG; (2) MS and MG blastocysts had a reduced number of TUNEL-positive cells compared to GC blastocysts; (3) though blastocyst mean cell numbers, mitochondrial activity, and lipid content were not different among the three culture conditions, MS blastocysts had a higher frequency of small-sized lipid droplets and a reduced mean droplet diameter compared with GC and MG blastocysts. Overall, findings open the way to optimize the development and competence of single embryos in an ART setting.


Assuntos
Blastocisto , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário , Zigoto , Animais , Bovinos , Blastocisto/citologia , Blastocisto/metabolismo , Zigoto/citologia , Zigoto/metabolismo , Técnicas de Cultura Embrionária/métodos , Feminino , Mitocôndrias/metabolismo
4.
Heliyon ; 10(8): e29728, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681593

RESUMO

The increasing emissions of greenhouse gases (GHG) and pollutants like particulate matter and nitrogen oxides (NOx) have led to environmental concerns. Hybrid and electric powertrains are being introduced as means to reduce pollutant emissions, especially at the local level. Additionally, the finite availability of fossil fuel sources, which are used to produce gasoline and diesel, highlights the need for alternative technical solutions. One approach to partly address these issues is lightweighting, which involves reducing the weight of vehicles to minimize their impact during the use phase. Mathematical models are employed to simulate the longitudinal dynamics of vehicles and estimate the energy required to accomplish driving missions. Appropriate metrics have been developed to quantify energy-saving effects that, in addition, can support the decision making, design, and development phase of future vehicles. To facilitate this process, it would be useful to build a database of ERV (Energy Reduction Value) and FRV (Fuel Reduction Value) figures derived through a unified procedure. Such a database would be useful in evaluating the effectiveness of vehicle lightweighting and its impact on energy consumption and pollutant emissions. The last phase of the analysis is the assessment of the overall reduction in the environmental impact of the vehicle throughout its life cycle by using the LCA (Life Cycle Assessment) approach. From this study, it was possible to conclude that lightweighting can be an appropriate solution to improve the energy efficiency of vehicles and that appropriate metrics, can support the development of new car models. The potential to integrate enhanced energy efficiency, lower emissions, and higher safety features into our everyday vehicles would represent a significant advancement in the automotive industry. There is a gap in the scientific literature on the effects of lightweighting on vehicle dynamics and energy usage which deserves to be investigated.

5.
Front Bioeng Biotechnol ; 12: 1310696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38390358

RESUMO

Introduction: We report the development and preliminary evaluation of a novel dynamic bioreactor to culture ovarian cortical tissue strips that leverages tissue response to enhanced oxygen transport and adequate mechanical stimulation. In vitro multistep ovarian tissue static culture followed by mature oocyte generation, fertilization, and embryo transfer promises to use the reserve of dormant follicles. Unfortunately, static in vitro culture of ovarian tissue does not promote development of primordial to secondary follicles or sustain follicle viability and thereby limits the number of obtainable mature oocytes. Enhancing oxygen transport to and exerting mechanical stimulation on ovarian tissue in a dynamic bioreactor may more closely mimic the physiological microenvironment and thus promote follicle activation, development, and viability. Materials and Methods: The most transport-effective dynamic bioreactor design was modified using 3D models of medium and oxygen transport to maximize strip perifusion and apply tissue fluid dynamic shear stresses and direct compressive strains to elicit tissue response. Prototypes of the final bioreactor design were manufactured with materials of varying cytocompatibility and assessed by testing the effect of leachables on sperm motility. Effectiveness of the bioreactor culture was characterized against static controls by culturing fresh bovine ovarian tissue strips for 7 days at 4.8 × 10-5 m/s medium filtration flux in air at -15% maximal total compressive strain and by assessing follicle development, health, and viability. Results and Conclusions: Culture in dynamic bioreactors promoted effective oxygen transport to tissues and stimulated tissues with strains and fluid dynamic shear stresses that, although non-uniform, significantly influenced tissue metabolism. Tissue strip culture in bioreactors made of cytocompatible polypropylene preserved follicle viability and promoted follicle development better than static culture, less so in bioreactors made of cytotoxic ABS-like resin.

6.
Science ; 375(6582): eabg1780, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35175823

RESUMO

Understanding animal movement is essential to elucidate how animals interact, survive, and thrive in a changing world. Recent technological advances in data collection and management have transformed our understanding of animal "movement ecology" (the integrated study of organismal movement), creating a big-data discipline that benefits from rapid, cost-effective generation of large amounts of data on movements of animals in the wild. These high-throughput wildlife tracking systems now allow more thorough investigation of variation among individuals and species across space and time, the nature of biological interactions, and behavioral responses to the environment. Movement ecology is rapidly expanding scientific frontiers through large interdisciplinary and collaborative frameworks, providing improved opportunities for conservation and insights into the movements of wild animals, and their causes and consequences.


Assuntos
Animais Selvagens/fisiologia , Comportamento Animal , Big Data , Ecologia , Meio Ambiente , Movimento , Migração Animal , Animais , Coleta de Dados , Ecossistema , Análise Espaço-Temporal
7.
J Anim Ecol ; 88(12): 2017-2021, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31524290

RESUMO

That this camera-based method is sparking debate regarding its applicability to specific-species is a symptom of the complexity of wildlife assessment in light of the increasing, unprecedented amount of ecological-data, this task requires strengthening links between theorists and empiricists to profit the new opportunities offered by the method.


Assuntos
Animais Selvagens , Ecologia , Animais
8.
Fractal rev. psicol ; 31(2): 67-75, maio-ago. 2019.
Artigo em Português | LILACS, Index Psicologia - Periódicos | ID: biblio-1039907

RESUMO

Este artigo nasce da inserção da equipe de psicologia numa oficina de dança do Centro de Referência de Mulheres da Maré - Carminha Rosa. Através da exploração e (re)conhecimento corporal proporcionado na oficina, percebemos a possibilidade de o corpo da mulher se desprender de uma identidade e se abrir para novos contornos e possibilidades de ser. Assim, o artigo objetiva pensar as interfaces entre psicologia e dança, refletindo sobre as possíveis contribuições destas às reflexões e produções no campo das políticas de gênero. Para tanto, realizaram-se entrevistas semiestruturadas com participantes da oficina e análise dos relatos da equipe de psicologia que acompanhava a oficina. Ao explorar o corpo como ponto de ancoragem da atuação da psicologia e das lutas pela igualdade de gênero, o texto conclui que a conexão entre psicologia, corpo e gênero representa uma possibilidade promissora tanto no que se refere à liberdade subjetiva quanto à superação das formas de dominação de gênero e que ambas as perspectivas merecem ser mais bem exploradas.(AU)


This article springs from the introduction of the psychology team in a dance workshop of the Maré Women Reference Center - Carminha Rosa. Through exploration and body recognition provided in the workshop, we percieved the possibility to let go of an identity and open up to new dimensions and possibilities of being. Thus, the article aims to think the interfaces between psychology and dance, reflecting on the posible contributions of these reflections and productions in the area of gender policies. For that we have done semi-structured interviews with workshop participants and analysis of the psychology team reports that followed the workshop. By exploring the body as the anchoring point of psychology and gender equality struggles, the text concludes that the connection between psychology, body and gender represents a promising possibility both in terms of subjective freedom and overcoming forms of domination of gender perspective, and these perspectives deserve further exploration.(AU)


Assuntos
Humanos , Feminino , Psicologia , Corpo Humano , Dança , Identidade de Gênero
9.
Ecol Lett ; 22(2): 213-232, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30467933

RESUMO

Consistent between-individual differences in movement are widely recognised across taxa. In addition, foraging plasticity at the within-individual level suggests a behavioural dependency on the internal energy demand. Because behaviour co-varies with fast-slow life history (LH) strategies in an adaptive context, as theoretically predicted by the pace-of-life syndrome hypothesis, mass/energy fluxes should link behaviour and its plasticity with physiology at both between- and within-individual levels. However, a mechanistic framework driving these links in a fluctuating ecological context is lacking. Focusing on home range behaviour, we propose a novel behavioural-bioenergetics theoretical model to address such complexities at the individual level based on energy balance. We propose explicit mechanistic links between behaviour, physiology/metabolism and LH by merging two well-founded theories, the movement ecology paradigm and the dynamic energetic budget theory. Overall, our behavioural-bioenergetics model integrates the mechanisms explaining how (1) behavioural between- and within-individual variabilities connect with internal state variable dynamics, (2) physiology and behaviour are explicitly interconnected by mass/energy fluxes, and (3) different LHs may arise from both behavioural and physiological variabilities in a given ecological context. Our novel theoretical model reveals encouraging opportunities for empiricists and theoreticians to delve into the eco-evolutionary processes that favour or hinder the development of between-individual differences in behaviour and the evolution of personality-dependent movement syndromes.


Assuntos
Ecologia , Comportamento de Retorno ao Território Vital , Movimento , Personalidade , Animais , Comportamento Animal , Metabolismo Energético
10.
PeerJ ; 6: e4707, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29785340

RESUMO

In the Balearic Islands, different trammel net designs have been adopted to promote fisheries sustainability and reduce discards. Here, we compare the catch performance of three trammel net designs targeting the spiny lobster Palinurus elephas in terms of biomass, species composition and revenue from commercial catches and discards. Designs differ in the netting fiber type (standard polyfilament, PMF, or a new polyethylene multi-monofilament, MMF) and the use of a guarding net or greca, a mesh piece intended to reduce discards. Catches were surveyed by an on-board observer from 1,550 netting walls corresponding to 70 nets. The number of marketable species captured indicated that the lobster trammel net fishery has multiple targets, which contribute significantly to the total revenue. The discarded species ranged from habitat-forming species to elasmobranches, but the magnitude of gear-habitat interactions on the long term dynamics of benthos remains unclear. No relevant differences in revenue and weight of discards were detected after Bayesian analyses. However, the species composition of discards was different when using greca. Interestingly, high immediate survival was found for discarded undersized lobsters, while a seven day survival assessment, using captive observation, gave an asymptotic estimate of survival probability as 0.64 (95% CI [0.54-0.76]). Therefore, it is recommended that it would be beneficial for this stock if an exemption from the EU landing obligation regulation was sought for undersized lobsters in the Balearic trammel net fishery.

11.
PeerJ ; 6: e4814, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29796349

RESUMO

The selective properties of fishing that influence behavioural traits have recently gained interest. Recent acoustic tracking experiments have revealed between-individual differences in the circadian behavioural traits of marine free-living fish; these differences are consistent across time and ecological contexts and generate different chronotypes. Here, we hypothesised that the directional selection resulting from fishing influences the wild circadian behavioural variation and affects differently to individuals in the same population differing in certain traits such as awakening time or rest onset time. We developed a spatially explicit social-ecological individual-based model (IBM) to test this hypothesis. The parametrisation of our IBM was fully based on empirical data; which represent a fishery formed by patchily distributed diurnal resident fish that are exploited by a fleet of mobile boats (mostly bottom fisheries). We ran our IBM with and without the observed circadian behavioural variation and estimated selection gradients as a quantitative measure of trait change. Our simulations revealed significant and strong selection gradients against early-riser chronotypes when compared with other behavioural and life-history traits. Significant selection gradients were consistent across a wide range of fishing effort scenarios. Our theoretical findings enhance our understanding of the selective properties of fishing by bridging the gaps among three traditionally separated fields: fisheries science, behavioural ecology and chronobiology. We derive some general predictions from our theoretical findings and outline a list of empirical research needs that are required to further understand the causes and consequences of circadian behavioural variation in marine fish.

12.
J Anim Ecol ; 87(3): 825-837, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29243250

RESUMO

The measurement of animal density may take advantage of recent technological achievements in wildlife video recording. Fostering the theoretical links between the patterns depicted by cameras and absolute density is required to exploit this potential. We explore the applicability of the Hutchinson-Waser's postulate (i.e. when animal density is stationary at a given temporal and spatial scale, the absolute density is given by the average number of animals counted per frame), which is a counter-intuitive statement for most ecologists and managers who are concerned with counting the same individual more than once. We aimed to reconcile such scepticism for animals displaying home range behaviour. The specific objectives of this paper are to generalize the Hutchinson-Waser's postulate for animals displaying home range behaviour and to propose a Bayesian implementation to estimate density from counts per frame using video cameras. Accuracy and precision of the method was evaluated by means of computer simulation experiments. Specifically, six animal archetypes displaying well-contrasted movement features were considered. The simulation results demonstrate that density could be accurately estimated after an affordable sampling effort (i.e. number of cameras and deployment time) for a great number of animals across taxa. The proposed method may complement other conventional methods for estimating animal density. The major advantages are that identifying an animal at the individual level and precise knowledge on how animals move are not needed, and that density can be estimated in a single survey. The method can accommodate conventional camera trapping data. The major limitations are related to some implicit assumptions of the underlying model: the home range centres should be homogeneously distributed, the detection probability within the area surveyed by the camera should be known, and animals should move independently to one another. Further improvements for circumventing these limitations are discussed.


Assuntos
Ecologia/métodos , Comportamento de Retorno ao Território Vital , Vertebrados/fisiologia , Gravação em Vídeo/métodos , Animais , Simulação por Computador , Modelos Biológicos , Densidade Demográfica , Gravação em Vídeo/instrumentação
13.
R Soc Open Sci ; 4(2): 160791, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28386434

RESUMO

Repeatable between-individual differences in the behavioural manifestation of underlying circadian rhythms determine chronotypes in humans and terrestrial animals. Here, we have repeatedly measured three circadian behaviours, awakening time, rest onset and rest duration, in the free-ranging pearly razorfish, Xyrithchys novacula, facilitated by acoustic tracking technology and hidden Markov models. In addition, daily travelled distance, a standard measure of daily activity as fish personality trait, was repeatedly assessed using a State-Space Model. We have decomposed the variance of these four behavioural traits using linear mixed models and estimated repeatability scores (R) while controlling for environmental co-variates: year of experimentation, spatial location of the activity, fish size and gender and their interactions. Between- and within-individual variance decomposition revealed significant Rs in all traits suggesting high predictability of individual circadian behavioural variation and the existence of chronotypes. The decomposition of the correlations among chronotypes and the personality trait studied here into between- and within-individual correlations did not reveal any significant correlation at between-individual level. We therefore propose circadian behavioural variation as an independent axis of the fish personality, and the study of chronotypes and their consequences as a novel dimension in understanding within-species fish behavioural diversity.

14.
Public Underst Sci ; 25(2): 236-51, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25186561

RESUMO

This work uses a qualitative approach coupled with a quantitative software-based methodology to examine the Italian news media coverage of radiation in the early decades of the twentieth century. We analyze 80 news stories from two of the most influential Italian newspapers from that time: La Stampa (a daily newspaper) and La Domenica del Corriere (an Italian Sunday supplement). While much of previous research on media coverage of scientific topics was generally focused on present-day news, our work revolves around the ground-breaking discovery of X-rays and radioactivity at the dawn of the last century. Our analysis aims to identify journalistic frames in the news coverage of radiation that journalists might have used to emphasize the benefits (or the risks) of the new discoveries. We also hypothesize how this kind of news coverage might have influenced public perception of technological, commercial, and public health applications of the new scientific advancements.


Assuntos
Jornais como Assunto/história , Radioatividade , Raios X , História do Século XIX , História do Século XX , Itália , Jornais como Assunto/estatística & dados numéricos , Opinião Pública/história
15.
Nuncius ; 30(2): 320-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26245007

RESUMO

At the beginning of the 20th century the collective imagination was fascinated and terrified by the discovery of radium. A scientific imagery sprang up around radioactivity and was disseminated by public lectures and newspaper articles discussing the ambiguous power of this strange substance. It was claimed that radium could be used to treat cholera, typhus and tuberculosis, but at the same time there were warnings that it could be used for military purposes. The media and the scientists themselves employed a rich vocabulary influenced by religion, alchemy and magic. The ambivalent power of radioactive elements exerted a great influence on science fiction novelists. This paper will examine some significant works published in Europe, America and Russia during the first decades of the 20th century and their role in the creation of the complex imagery of radioactivity that seized the public imagination long before the invention of the atomic bomb.


Assuntos
Elementos Radioativos/história , Literatura Moderna/história , Medicina na Literatura , Energia Nuclear/história , Radioatividade , Europa (Continente) , História do Século XX , América do Norte , Armas Nucleares/história , Rádio (Elemento)/história
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