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1.
Braz J Vet Med ; 46: e006323, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38384378

RESUMEN

Experimental animal facilities can have a negative impact on the well-being of animals owing to confinement. To mitigate this, environmental enrichment (EE) is implemented confinement. The purpose of EE is to enhance the complexity of an animal's natural environment. The objective of this study was to identify the types of EE most enjoyed by dogs used in experimental research and housed in individual kennels. A total of six adult Beagle dogs, housed at the Laboratório de Quimioterapia Experimental em Parasitologia Veterinária (LQEPV) at the Universidade Federal Rural do Rio de Janeiro (UFRRJ) were included in the study. The EE tools used included Petball® toys, a grassy outdoor area, interaction with other dogs and with a team member, a "pool" made of plastic bottles, and dog's wet food ice cream. A team member assessed the usage of these tools every 5 min for a 30-min period, six times per day, one day per week, over the course of eight weeks. The study revealed that the grass area was the tool most commonly used for physical enrichment, accounting for 58% of the occurrences (p < 0.05). Social and food enrichment were enjoyed in second and third place, with 23% and 19% of occurrences, respectively. that the study findings suggest that dogs housed in individual kennels enjoy engaging in their natural behaviors.


Os animais de biotério podem viver em situações que afetem o seu bem-estar, como o confinamento. Um dos métodos que buscam para reduzir os impactos negativos é o Enriquecimento Ambiental (EA), o qual objetiva a promoção da complexidade do ambiente dos animais. Foi possível, com esta pesquisa, atingir o objetivo de identificar quais tipos de EA são mais aproveitados por cães utilizados em pesquisas experimentais que viviam em canis individuais. Foram utilizados seis cães adultos, Beagles, oriundos do Laboratório de Quimioterapia Experimental em Parasitologia Veterinária (LQEPV) da Universidade Federal Rural do Rio de Janeiro (UFRRJ). Como ferramentas de EA foram utilizados brinquedos Petball®, área de grama ao ar livre, interação com outros cães e com uma pessoa da equipe, "piscina" de garrafas plásticas e sorvete de ração úmida. Um membro da equipe avaliou o uso a cada 5 minutos, por período de 30 minutos (6 avaliações) por dia, um dia por semana ao longo de 8 semanas. O estudo revelou que a ferramenta mais usufruída pelos cães foi a área de grama através do enriquecimento físico, quantificado em 58% de ocorrência (p<0,05). Os enriquecimentos sociais e alimentar, foram usufruídos em segundo e terceiro lugar, com 23% e 19% de ocorrência, respectivamente. Pode-se concluir que os cães mantidos em canis individuais individualizados mais necessitam exercer seu comportamento natural específico, para que seu grau de bem-estar seja mantido em nível satisfatório e em consequência sua saúde mental.

2.
Colloids Surf B Biointerfaces ; 234: 113758, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38241892

RESUMEN

Currently, cancer poses a significant health challenge in the medical community. Traditional chemotherapeutic agents are often accompanied by toxic side effects and limited therapeutic efficacy, restricting their application and advancement in cancer treatment. Therefore, there is an urgent need for developing intelligent drug release systems. Mesoporous silica nanoparticles (MSNs) have many advantages, such as a large specific surface area, substantial pore volume and size, adjustable mesoporous material pore size, excellent biocompatibility, and thermodynamic stability, making them ideal carriers for drug delivery and release. Additionally, they have been widely used to develop novel anticancer drug carriers. Recently, MSNs have been employed to design responsive systems that react to the tumor microenvironment and external stimuli for controlled release of anticancer drugs. This includes factors within the intratumor environment, such as pH, temperature, enzymes, and glutathione as well as external tumor stimuli, such as light, magnetic field, and ultrasound, among others. In this review, we discuss the research progress on environmental stimulus-responsive MSNs in anticancer drug delivery systems, including internal and external environment single stimulus-responsive release and combined stimulus-responsive release. We also summarize the current challenges associated with environmental stimulus-responsive MSNs and elucidate future directions, providing a reference for the functionalization modification and practical application of these MSNs.


Asunto(s)
Antineoplásicos , Nanopartículas , Neoplasias , Humanos , Dióxido de Silicio , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico , Nanopartículas/uso terapéutico , Liberación de Fármacos , Porosidad , Portadores de Fármacos , Microambiente Tumoral
3.
Biomimetics (Basel) ; 8(2)2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37366837

RESUMEN

An interactive artificial ecological optimization algorithm (SIAEO) based on environmental stimulus and a competition mechanism was devised to find the solution to a complex calculation, which can often become bogged down in local optimum because of the sequential execution of consumption and decomposition stages in the artificial ecological optimization algorithm. Firstly, the environmental stimulus defined by population diversity makes the population interactively execute the consumption operator and decomposition operator to abate the inhomogeneity of the algorithm. Secondly, the three different types of predation modes in the consumption stage were regarded as three different tasks, and the task execution mode was determined by the maximum cumulative success rate of each individual task execution. Furthermore, the biological competition operator is recommended to modify the regeneration strategy so that the SIAEO algorithm can provide consideration to the exploitation in the exploration stage, break the equal probability execution mode of the AEO, and promote the competition among operators. Finally, the stochastic mean suppression alternation exploitation problem is introduced in the later exploitation process of the algorithm, which can tremendously heighten the SIAEO algorithm to run away the local optimum. A comparison between SIAEO and other improved algorithms is performed on the CEC2017 and CEC2019 test set.

4.
BMC Biol ; 20(1): 274, 2022 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-36482454

RESUMEN

BACKGROUND: Root development and function have central roles in plant adaptation to the environment. The modification of root traits has additionally been a major driver of crop performance since the green revolution; however, the molecular underpinnings and the regulatory programmes defining root development and response to environmental stress remain largely unknown. Single-cell reconstruction of gene regulatory programmes provides an important tool to understand the cellular phenotypic variation in complex tissues and their response to endogenous and environmental stimuli. While single-cell transcriptomes of several plant organs have been elucidated, the underlying chromatin landscapes associated with cell type-specific gene expression remain largely unexplored. RESULTS: To comprehensively delineate chromatin accessibility during root development of an important crop, we applied single-cell ATAC-seq (scATAC-seq) to 46,758 cells from rice root tips under normal and heat stress conditions. Our data revealed cell type-specific accessibility variance across most of the major cell types and allowed us to identify sets of transcription factors which associate with accessible chromatin regions (ACRs). Using root hair differentiation as a model, we demonstrate that chromatin and gene expression dynamics during cell type differentiation correlate in pseudotime analyses. In addition to developmental trajectories, we describe chromatin responses to heat and identify cell type-specific accessibility changes to this key environmental stimulus. CONCLUSIONS: We report chromatin landscapes during rice root development at single-cell resolution. Our work provides a framework for the integrative analysis of regulatory dynamics in this important crop organ at single-cell resolution.


Asunto(s)
Meristema , Oryza , Cromatina/genética , Oryza/genética
5.
Sports Biomech ; : 1-17, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35139757

RESUMEN

Virtual reality (VR) can be used to alter the environment and challenge sensory calibration which rehabilitation and return-to-sport testing lack. The purpose was to establish how VR manipulation of the environment changes knee landing biomechanics. Twenty-nine healthy active adults (22 males; 20.52 ± 1.21 years; 1.75 ± 0.09 m; 78.34 ± 14.33 kg) were recruited. Three drop landing trials (31 cm height box) were performed for three conditions: eyes-open (EO), eyes-closed (EC), and VR, consisting of a head-mounted display of a 360° photo of a steep man-made edge or drop. Knee kinematics and kinetics were evaluated using 3D motion capture. The VR condition significantly increased Landing Error Score System errors relative to EO (1.28 ± 0.20, p < 0.001) and EC (0.98 ± 0.22, p < 0.001) and increased vertical ground reaction force relative to EO (0.41 ± 0.09 N·bw-1, p < 0.001) and EC (0.34 ± 0.07 N·bw-1, p < 0.001). The VR condition had less knee flexion at initial contact compared to EO (4.39 ± 0.75°, p = 0.001) and EC (1.83 ± 0.63°, p = 0.021). The VR condition had more knee abduction at initial contact compared to EO (0.71 ± 0.24°, p = 0.002) and EC (0.69 ± 0.22°, p = 0.002) and increased knee abduction at maximum flexion compared to EO (2.01 ± 0.58°, p = 0.026). Landing in VR increased injury risk landing biomechanics, indicating that VR may option to incorporate into return-to-play or injury risk assessment.

6.
Plant Mol Biol ; 104(6): 561-574, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32980951

RESUMEN

KEY MESSAGE: This study focused on the role of CLE1-CLE7 peptides as environmental mediators and indicated that root-induced CLE2 functions systemically in light-dependent carbohydrate metabolism in shoots. Plants sense environmental stimuli and convert them into cellular signals, which are transmitted to distinct cells and tissues to induce adequate responses. Plant hormones and small secretory peptides often function as environmental stress mediators. In this study, we investigated whether CLAVATA3/EMBRYO SURROUNDING REGION-RELATED proteins, CLE1-CLE7, which share closely related CLE domains, mediate environmental stimuli in Arabidopsis thaliana. Expression analysis of CLE1-CLE7 revealed that these genes respond to different environmental stimuli, such as nitrogen deprivation, nitrogen replenishment, cold, salt, dark, and sugar starvation, in a sophisticated manner. To further investigate the function of CLE2, we generated transgenic Arabidopsis lines expressing the ß-glucuronidase gene under the control of the CLE2 promoter or expressing the CLE2 gene under the control of an estradiol-inducible promoter. We also generated cle2-1 and cle2-2 mutants using the CRISPR/Cas9 technology. In these transgenic lines, dark induced the expression of CLE2 in the root vasculature. Additionally, induction of CLE2 in roots induced the expression of various genes not only in roots but also in shoots, and genes related to light-dependent carbohydrate metabolism were particularly induced in shoots. In addition, cle2 mutant plants showed chlorosis when subjected to a shade treatment. These results suggest that root-induced CLE2 functions systemically in light-dependent carbohydrate metabolism in shoots.


Asunto(s)
Proteínas de Arabidopsis/fisiología , Arabidopsis/metabolismo , Metabolismo de los Hidratos de Carbono , Brotes de la Planta/metabolismo , Arabidopsis/genética , Arabidopsis/efectos de la radiación , Proteínas de Arabidopsis/genética , Sistemas CRISPR-Cas , Oscuridad , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Interacción Gen-Ambiente , Luz , Brotes de la Planta/efectos de la radiación , Plantas Modificadas Genéticamente , Dominios Proteicos/genética , Transducción de Señal
7.
Environ Toxicol Chem ; 39(9): 1755-1764, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32539175

RESUMEN

Infochemicals act as inter- or intraspecific messengers. The literature suggests complex interactions between infochemicals (mainly predator cues) and chemical (e.g., pesticide) effects, with their direction and magnitude depending on the cue origin, pesticide identity, and test species. With the present study we assessed the impact of alarm cues alone and in combination with the neonicotinoid insecticide thiacloprid on leaf consumption, predation on Baetis nymphs, and dry weight of the amphipod Gammarus fossarum. Alarm cues (ground gammarids) and thiacloprid alone decreased gammarid leaf consumption with increasing intensities. At a defined alarm cue intensity, which alone did not cause a significant reduction in gammarid feeding, thiacloprid-induced feeding effects were additive. During an experiment targeting gammarid predation on Baetis nymphs (120 h), thiacloprid and alarm cues alone did increase and reduce predation significantly, respectively. Moreover, alarm cues led to a lower final gammarid dry weight. However, alarm cues did not affect response variables during a second predation experiment performed at a higher thiacloprid concentration (2 vs 0.75 µg/L). This discrepancy in alarm cue effects highlights either a varying susceptibility of the test species to these cues among experiments or that cue quality is fluctuating. Thus, the present study highlights a considerable variability in the individual and interactive effects of infochemicals and chemical stressors on aquatic biota, an insight relevant in the assessment of multiple stressors. Environ Toxicol Chem 2020;39:1755-1764. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Asunto(s)
Anfípodos/crecimiento & desarrollo , Neonicotinoides/toxicidad , Hojas de la Planta/fisiología , Conducta Predatoria/efectos de los fármacos , Pruebas de Toxicidad , Anfípodos/efectos de los fármacos , Animales , Análisis Factorial , Insecticidas/toxicidad , Larva/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Tiazinas/toxicidad
8.
Front Chem ; 7: 725, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31781535

RESUMEN

Benefiting from unique planar structure, high flexibility, splendid thermal, and electric properties; graphene as a crucial component has been widely applied into smart materials and multi-stimulus responsive actuators. Moreover, graphene with easy processing and modification features can be decorated with various functional groups through covalent or non-covalent bonds, which is promising in the conversion of environmental energy from single and/or multi-stimuli, to mechanical energy. In this review, we present the actuating behaviors of graphene, regulated by chemical bonds or intermolecular forces under multi-stimuli and summarize the recent advances on account of the unique nanostructures in various actuation circumstances such as thermal, humidity, electrochemical, electro-/photo-thermal, and other stimuli.

9.
Mar Genomics ; 24 Pt 3: 207-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26024611

RESUMEN

In this study, the whole transcriptome of Tigriopus japonicus was sequenced using next generation sequencing technology. De novo assembly was performed using Trinity, which assembled 140,130 contigs. Transdecoder found 54,761 candidate coding contigs, 39,507 of which showed homology to other species covering 15,310 genes by BLAST analysis. Functional gene annotation was performed by Gene Ontology, InterProScan, and KEGG pathway analyses. In addition to various metabolism-related pathways, xenobiotic biodegradation and metabolism were other interesting pathways in T. japonicus. Transcripts encoding various enzymes (e.g. superoxide dismutase, heat shock protein, and peroxidases) in response to a variety of stimuli were identified, which might be useful candidate biomarkers for ecotoxicology studies.


Asunto(s)
Copépodos/genética , Copépodos/metabolismo , Metabolismo Energético/genética , Metabolismo Energético/fisiología , Regulación de la Expresión Génica/fisiología , Transcriptoma , Animales
10.
Plant Cell Environ ; 38(7): 1333-46, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25402319

RESUMEN

Increasing temperatures due to changing global climate are interfering with plant-pollinator mutualism, an interaction facilitated mainly by floral colour and scent. Gas chromatography-mass spectroscopy analyses revealed that increasing ambient temperature leads to a decrease in phenylpropanoid-based floral scent production in two Petunia × hybrida varieties, P720 and Blue Spark, acclimated at 22/16 or 28/22 °C (day/night). This decrease could be attributed to down-regulation of scent-related structural gene expression from both phenylpropanoid and shikimate pathways, and up-regulation of a negative regulator of scent production, emission of benzenoids V (EOBV). To test whether the negative effect of increased temperature on scent production can be reduced in flowers with enhanced metabolic flow in the phenylpropanoid pathway, we analysed floral volatile production by transgenic 'Blue Spark' plants overexpressing CaMV 35S-driven Arabidopsis thaliana production of anthocyanin pigments 1 (PAP1) under elevated versus standard temperature conditions. Flowers of 35S:PAP1 transgenic plants produced the same or even higher levels of volatiles when exposed to a long-term high-temperature regime. This phenotype was also evident when analysing relevant gene expression as inferred from sequencing the transcriptome of 35S:PAP1 transgenic flowers under the two temperature regimes. Thus, up-regulation of transcription might negate the adverse effects of temperature on scent production.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Petunia/metabolismo , Factores de Transcripción/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Antocianinas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulación hacia Abajo , Flores/genética , Flores/crecimiento & desarrollo , Cromatografía de Gases y Espectrometría de Masas , Expresión Génica , Calor , Proteínas Asociadas a Pancreatitis , Petunia/genética , Petunia/crecimiento & desarrollo , Fenotipo , Plantas Modificadas Genéticamente , Propanoles/metabolismo , Ácido Shikímico/metabolismo , Factores de Transcripción/genética , Activación Transcripcional , Transcriptoma , Regulación hacia Arriba
11.
Rev. etol. (Online) ; 10(1): 12-20, jun. 2011. ilus, tab
Artículo en Portugués | Index Psicología - Revistas | ID: psi-58256

RESUMEN

Animais em cativeiro tendem a viver em ambientes altamente previsíveis e estruturados onde raramente apresentam desafios do ambiente natural, e isso pode desencadear uma série de casos de extrema-respostas adaptativas. O objetivo deste trabalho foi avaliar o bem-estar de um bugio cativo após o enriquecimento social e ambiental, assim como analisar, durante cada tratamento, a interação com os enriquecimentos ao longo dos dias. Os resultados apontaram uma diminuição contínua da maioria dos comportamentos estereotipados e aumento na interação social em todas as fases de enriquecimento. Estes resultados mostraram que houve uma melhoria no bem-estar deste animal após a introdução da fêmea e do espelho.(AU)


Animals in captivity tend to live in highly structured and predictable where rarely present challenges of the natural environment and this can trigger a series of cases of extreme adaptive responses. The aim of this study was to evaluate the welfare of captive howler monkey after a social and environmental enrichment. Beyond to analyze, for each treatment, the interaction with the enrichments along the days. Results showed a continuous decrease in the most stereotyped behaviors and increased social interaction at all stages of enrichment. These results showed an improvement in the welfare of this animal after the introduction of the female and the mirror.(AU)


Asunto(s)
Animales , Alouatta , Primates , Ambiente , Etología , Bienestar del Animal
12.
Rev. etol. (Online) ; 10(1): 12-20, June 2011. ilus, tab
Artículo en Portugués | LILACS | ID: lil-701983

RESUMEN

Animais em cativeiro tendem a viver em ambientes altamente previsíveis e estruturados onde raramente apresentam desafios do ambiente natural, e isso pode desencadear uma série de casos de extrema-respostas adaptativas. O objetivo deste trabalho foi avaliar o bem-estar de um bugio cativo após o enriquecimento social e ambiental, assim como analisar, durante cada tratamento, a interação com os enriquecimentos ao longo dos dias. Os resultados apontaram uma diminuição contínua da maioria dos comportamentos estereotipados e aumento na interação social em todas as fases de enriquecimento. Estes resultados mostraram que houve uma melhoria no bem-estar deste animal após a introdução da fêmea e do espelho.


Animals in captivity tend to live in highly structured and predictable where rarely present challenges of the natural environment and this can trigger a series of cases of extreme adaptive responses. The aim of this study was to evaluate the welfare of captive howler monkey after a social and environmental enrichment. Beyond to analyze, for each treatment, the interaction with the enrichments along the days. Results showed a continuous decrease in the most stereotyped behaviors and increased social interaction at all stages of enrichment. These results showed an improvement in the welfare of this animal after the introduction of the female and the mirror.


Asunto(s)
Animales , Alouatta , Bienestar del Animal , Ambiente , Etología , Primates
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