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1.
J Therm Biol ; 114: 103577, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37263039

RESUMO

Global projections predict significant increases in ocean temperature and changes in ocean chemistry, including salinity variations by 2100. This has led to a substantial interest in the study of thermal ecophysiology, as temperature is a major factor shaping marine ectotherm communities. However, responses to temperature may be influenced by other factors such as salinity, highlighting the relevance of multiple stressor studies. In the present work, we experimentally evaluated the thermal tolerance of the marine ragworm Hediste diversicolor under predicted global change scenarios. Organisms were subjected to an experimental trial under control (24 °C), and two temperature treatment scenarios (ocean warming +3 °C - (27 °C) and heat wave +6 °C - (30 °C)), combined with salinity variations (20 and 30) in a full factorial design for 29 days. Environmental data from the field were collected during 2019 and 2020. At day 30 post exposure, upper thermal limits (Critical Thermal Maximum - CTMax), thermal safety margins (TSM) and acclimation capacity were measured. Higher acclimation temperatures led to higher thermal tolerance limits, confirming that H. diversicolor features some physiological plasticity, acclimation capacity and a positive thermal safety margin. This margin was greater considering in situ temperature data from 2019 than maximum temperatures for 2020 (CTMax > maximum habitat temperature-MHT). Moreover, smaller organisms displayed higher upper thermal limits suggesting that thermal tolerance is size dependent. Ragworms subjected to higher salinity also showed a higher CTMax than those acclimated to lower salinity. However, temperature and salinity showed an additive effect on CTMax, as no significant interaction was detected. We conclude that H. diversicolor can easily acclimate to increased water temperature, independently of salinity variations. Given the key role of ragworms in food webs in estuaries and coastal lagoons, substrate bioturbation and aquaculture, this information is relevant to support conservation actions, optimize culture protocols and identify thermal resistant strains.


Assuntos
Aclimatação , Temperatura Alta , Aclimatação/fisiologia , Temperatura , Salinidade , Ecossistema
2.
J Therm Biol ; 103: 103151, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35027201

RESUMO

As global temperatures continue to rise due to global change, marine heatwaves are also becoming more frequent and intense, impacting marine biodiversity patterns worldwide. Organisms inhabiting shallow water environments, such as the commercially relevant ditch shrimp Palaemon varians, are expected to be the most affected by rising temperatures. Thus, addressing species' thermal ecology and climate extinction-risk is crucial to foster climate-smart conservation strategies for shallow water ecosystems. Here, we estimated sex-specific upper thermal tolerance limits for P. varians via the Critical Thermal Maximum method (CTmax), using loss of equilibrium as endpoint. We further calculated thermal safety margins for males and females and tested for correlations between upper thermal limits and shrimps' body size. To determine sex-biased variation in P. varians' traits (CTmax, weight and length), we compared trait variation between females and males through the coefficient of variation ratio (lnCVR). Females displayed an average CTmax value 1.8% lower than males (CTmaxfemales = 37.0 °C vs CTmaxmales = 37.7 °C). This finding may be related to the larger body size exhibited by females (156% heavier and 39% larger than males), as both length and weight had a significant effect on CTmax. The high energetic investment of females in offspring may also contribute to the differences recorded in thermal tolerance. Overall, organisms with a smaller body-size displayed a greater tolerance to elevated temperature, thus suggesting that smaller individuals may be positively selected in warmer environments. This selection may result in a reduction of size-at-maturity and shifts in sex ratio, given the sexual dimorphism in body size of shrimps. The thermal safety margin of P. varians was narrow (∼2.2 °C for males and ∼1.5 °C for females), revealing the vulnerability of this species to ocean warming and heatwaves.


Assuntos
Biodiversidade , Evolução Biológica , Tamanho Corporal , Palaemonidae/fisiologia , Termotolerância , Aclimatação , Animais , Mudança Climática , Feminino , Masculino , Oceanos e Mares , Temperatura
3.
Viana do Castelo; s.n; 20211028.
Tese em Português | BDENF - Enfermagem | ID: biblio-1343822

RESUMO

Introdução: O aumento da esperança média de vida e, naturalmente da prevalência de doenças osteoarticulares, tem possibilitado à cirurgia ortopédica obter protagonismo no tratamento da coxartrose, sendo a artroplastia total da anca (ATA) o procedimento cirúrgico mais empregue e efetivo no alívio da dor, aumento da capacidade funcional e diminuição das limitações. Para a Enfermagem de Reabilitação é impreterível o conhecimento dessas limitações e um diagnóstico funcional dos doentes com coxartrose. O enfermeiro especialista em enfermagem de reabilitação (EEER) deve promover intervenções preventivas, junto do doente, a fim de garantir a preservação da sua capacidade funcional, evitando a incapacidade e morbilidade. Como tal, nasce assim, a necessidade da capacitação pré-operatória das pessoas submetidas a ATA, aspeto que tem vindo a ser defendido como crucial no plano de reabilitação, no qual o sucesso da ATA advém do conhecimento e do ensino proporcionado à pessoa à priori. Objetivos: Compreender que tipo de informações foram dadas no pré-operatório acerca de cuidados e estratégias adaptativas ao utente submetido a ATA; compreender o impacto da intervenção do enfermeiro de reabilitação ao utente submetido a ATA ao nível do autocuidado: higiene, vestir-se e andar com auxiliar de marcha e compreender quais as expectativas do enfermeiro de reabilitação relativamente à consulta de enfermagem pré-operatória ao utente submetido a ATA. Metodologia: Para a realização deste estudo optamos pela metodologia de projeto e a população alvo foi constituída por quatro Enfermeiros Especialistas em Enfermagem de Reabilitação a exercer a sua atividade profissional em Hospital ou ECCI. Como instrumento de colheita de dados elaboramos um questionário, composto por três grupos e uma pergunta aberta. O primeiro grupo reportava às variáveis sociodemográficas, o grupo II à Consulta de Enfermagem de Reabilitação e o grupo III ao contexto da alta hospitalar e foi aplicado sob a forma de entrevista. Resultados e Discussão: Verificamos a unanimidade nas respostas dos enfermeiros em concluir a importância da preparação pré-operatória do doente, tanto ao nível da autonomia, como na aquisição de competência como a marcha, mobilização ou posicionamento e, até, na preparação da família e dos domicílios, tornando-os mais funcionais. Conclusões: Os dados obtidos reforçam a importância de uma consulta pré-operatória na pessoa submetida a ATA.


Introduction: The increase in average life expectancy and, naturally, the prevalence of osteoarticular diseases has enabled orthopedic surgery to play a leading role in the treatment of coxarthrosis, with total hip arthroplasty (THA) being the most used and effective surgical procedure for pain relief, increased functional capacity and reduced limitations. For Rehabilitation Nursing, knowledge of these limitations and a functional diagnosis of patients with coxarthrosis is essential. The specialist nurse in rehabilitation nursing must promote preventive interventions with the patient, to ensure the preservation of their functional capacity, avoiding disability and morbidity. As such, the need for preoperative training of people undergoing ATA is born, an aspect that has been defended as crucial in the rehabilitation plan, in which total hip arthroplasty success comes from the knowledge and teaching provided to the person a priori. Objectives: To understand what kind of information was given in the preoperative period about care and adaptive strategies for patients undergoing THA; understand the impact of the intervention of the rehabilitation nurse on the patient undergoing THA in terms of self-care: hygiene, dressing and walking with a walking aid and understand what the rehabilitation nurse's expectations regarding the preoperative nursing consultation for the patient submitted are the THA. Methodology: To carry out this study, we chose the project methodology and the target population consisted of four Specialist Nurses in Rehabilitation Nursing, exercising their professional activity in a hospital or in the community. As a data collection instrument, we created a questionnaire, consisting of three groups and an open question. The first group reported the sociodemographic variables, group II to the Rehabilitation Nursing Consultation and group III to the context of hospital discharge and was applied in the form of an interview. Results and Discussion: We found that nurses' responses were unanimous in concluding the importance of preoperative preparation of the patient, both in terms of autonomy and in the acquisition of competence such as walking, mobilizing, or positioning, and even in preparing the family and of households, making them more functional. Conclusions: The data obtained reinforce the importance of a preoperative consultation in the person undergoing THA.


Assuntos
Osteoartrite do Quadril , Enfermagem em Reabilitação , Artroplastia de Quadril , Tutoria
4.
Sci Total Environ ; 795: 148634, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34246144

RESUMO

Estuarine systems are critical transition zones influenced by sea, land and freshwater. An array of human activities impacts these areas leading to multiple-stressor interactions. Temperature and salinity are among the most relevant drivers in estuaries, shaping species growth, reproduction and distribution. However, few studies provide an overview of cellular rewiring processes under multiple-stressor environments. Here, we tested how salinity could shape the response of ragworms Hediste diversicolor, an important bioindicator and commercial species, to elevated temperature. We exposed polychaetes to three temperatures for a month, simulating control, ocean warming and heatwave conditions (24, 27 and 30 °C, respectively) combined with two salinities (20 and 30). We quantified whole-organism performance (wet weight gain and survival), along with cellular stress response (CSR) and energy reserves of worms after 14 and 28 days of exposure. Significant three-way interactions between temperature, salinity and exposure time show the non-linearity of molecular responses. Worms at a salinity of 20 were more sensitive to warming than worms exposed to a salinity of 30. The combination of high temperature and low salinity can act synergistically to induce oxidative stress and macromolecular damage in worm tissues. This finding was supported by an induction of the CSR, with a concomitant decrease of energy reserves, pointing towards a metabolic compensation strategy. However, under a higher salinity (30), the need for a CSR upon thermal challenge was reduced and energy content increased with temperature, which suggests that environmental conditions were within the optimum range. Heatwaves striking low-salinity areas of estuaries can therefore negatively impact the cellular physiology of H. diversicolor, with greater metabolic costs. However, extreme stress levels were not reached as worms incremented wet weight and survival was high under all conditions tested. Our findings are important for the optimization of ragworm aquaculture and adaptive conservation strategies of estuarine systems.


Assuntos
Poliquetos , Poluentes Químicos da Água , Animais , Humanos , Estresse Oxidativo , Fenótipo , Salinidade
5.
Environ Res ; 195: 110885, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33609552

RESUMO

Extreme weather events, such as heatwaves, are becoming increasingly frequent, long-lasting and severe as global climate change continues, shaping marine biodiversity patterns worldwide. Increased risk of overheating and mortality across major taxa have been recurrently observed, jeopardizing the sustainability of ecosystem services. Molecular responses of species, which scale up to physiological and population responses, are determinant processes that modulate species sensitivity or tolerance to extreme weather events. Here, by integrating proteomic, fatty acid profiling and physiological approaches, we show that the tolerance of the intertidal ragworm Hediste diversicolor, a keystone species in estuarine ecosystems and an emergent blue bio-resource, to long-lasting heatwaves (24  vs 30 °C for 30 days) is shaped by calcium homeostasis, immune function and stability of fatty acid profiles. These features potentially enabled H. diversicolor to increase its thermal tolerance limit by 0.81 °C under the heatwave scenario and maintain survival. No growth trade-offs were detected, as wet weight remained stable across conditions. Biological variation of physiological parameters was lower when compared to molecular measures. Proteins showed an overall elevated coefficient of variation, although decreasing molecular variance under the heatwave scenario was observed for both proteins and fatty acids. This finding is consistent with the phenomenon of physiological canalization in extreme environments and contradicts the theory that novel conditions increase trait variation. Our results show that keystone highly valued marine polychaetes are tolerant to heatwaves, confirming the potential of H. diversicolor as a blue bio-resource and opening new avenues for sustainable marine aquaculture development.


Assuntos
Ecossistema , Poliquetos , Animais , Cálcio , Ácidos Graxos , Homeostase , Proteômica
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