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1.
Artigo em Inglês | MEDLINE | ID: mdl-29158138

RESUMO

Future climate change scenarios predict threatening outcomes to biodiversity. Available empirical data concerning biological response of freshwater fish to climate change remains scarce. In this study, we investigated the physiological and biochemical responses of two Iberian freshwater fish species (Squalius carolitertii and the endangered S. torgalensis), inhabiting different climatic conditions, to projected future scenarios of warming (+3°C) and acidification (ΔpH=-0.4). Herein, metabolic enzyme activities of glycolytic (citrate synthase - CS, lactate dehydrogenase - LDH) and antioxidant (glutathione S-transferase, catalase and superoxide dismutase) pathways, as well as the heat shock response (HSR) and lipid peroxidation were determined. Our results show that, under current water pH, warming causes differential interspecific changes on LDH activity, increasing and decreasing its activity in S. carolitertii and in S. torgalensis, respectively. Furthermore, the synergistic effect of warming and acidification caused an increase in LDH activity of S. torgalensis, comparing with the warming condition. As for CS activity, acidification significantly decreased its activity in S. carolitertii whereas in S. torgalensis no significant effect was observed. These results suggest that S. carolitertii is more vulnerable to climate change, possibly as the result of its evolutionary acclimatization to milder climatic condition, while S. torgalensis evolved in the warmer Mediterranean climate. However, significant changes in HSR were observed under the combined warming and acidification (S. carolitertii) or under acidification (S. torgalensis). Our results underlie the importance of conducting experimental studies and address species endpoint responses under projected climate change scenarios to improve conservation strategies, and to safeguard endangered freshwater fish.


Assuntos
Aclimatação , Ácidos/metabolismo , Cyprinidae/fisiologia , Água Doce , Resposta ao Choque Térmico , Temperatura Alta , Animais , Antioxidantes/metabolismo , Enzimas/metabolismo , Glicólise , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos , Estresse Oxidativo , Especificidade da Espécie
2.
Glob Chang Biol ; 20(10): 3068-79, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24771544

RESUMO

Cleaning symbioses play an important role in the health of certain coastal marine communities. These interspecific associations often occur at specific sites (cleaning stations) where a cleaner organism (commonly a fish or shrimp) removes ectoparasites/damaged tissue from a 'client' (a larger cooperating fish). At present, the potential impact of climate change on the fitness of cleaner organisms remains unknown. This study investigated the physiological and biochemical responses of tropical (Lysmata amboinensis) and temperate (L. seticaudata) cleaner shrimp to global warming. Specifically, thermal limits (CTMax), metabolic rates, thermal sensitivity, heat shock response (HSR), lipid peroxidation [malondialdehyde (MDA) concentration], lactate levels, antioxidant (GST, SOD and catalase) and digestive enzyme activities (trypsin and alkaline phosphatase) at current and warming (+3 °C) temperature conditions. In contrast to the temperate species, CTMax values decreased significantly from current (24-27 °C) to warming temperature conditions (30 °C) for the tropical shrimp, where metabolic thermal sensitivity was affected and the HSR was significantly reduced. MDA levels in tropical shrimp increased dramatically, indicating extreme cellular lipid peroxidation, which was not observed in the temperate shrimp. Lactate levels, GST and SOD activities were significantly enhanced within the muscle tissue of the tropical species. Digestive enzyme activities in the hepatopancreas of both species were significantly decreased by warmer temperatures. Our data suggest that the tropical cleaner shrimp will be more vulnerable to global warming than the temperate Lysmata seticaudata; the latter evolved in a relatively unstable environment with seasonal thermal variations that may have conferred greater adaptive plasticity. Thus, tropical cleaning symbioses may be challenged at a greater degree by warming-related anthropogenic forcing, with potential cascading effects on the health and structuring of tropical coastal communities (e.g. coral reefs).


Assuntos
Aclimatação/fisiologia , Antioxidantes/metabolismo , Mudança Climática , Crustáceos/fisiologia , Enzimas/metabolismo , Temperatura Alta , Estresse Fisiológico , Animais , Organismos Aquáticos , Crustáceos/metabolismo , Resposta ao Choque Térmico , Peroxidação de Lipídeos , Especificidade da Espécie , Simbiose
3.
J Exp Biol ; 217(Pt 12): 2062-70, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24625652

RESUMO

Early life stages of many marine organisms are being challenged by rising seawater temperature and CO2 concentrations, but their physiological responses to these environmental changes still remain unclear. In the present study, we show that future predictions of ocean warming (+4°C) and acidification (ΔpH=0.5 units) may compromise the development of early life stages of a highly commercial teleost fish, Solea senegalensis. Exposure to future conditions caused a decline in hatching success and larval survival. Growth, metabolic rates and thermal tolerance increased with temperature but decreased under acidified conditions. Hypercapnia and warming amplified the incidence of deformities by 31.5% (including severe deformities such as lordosis, scoliosis and kyphosis), while promoting the occurrence of oversized otoliths (109.3% increase). Smaller larvae with greater skeletal deformities and larger otoliths may face major ecophysiological challenges, which might potentiate substantial declines in adult fish populations, putting in jeopardy the species' fitness under a changing ocean.


Assuntos
Osso e Ossos/anormalidades , Mudança Climática , Linguados/anormalidades , Linguados/fisiologia , Membrana dos Otólitos/embriologia , Reprodução , Animais , Osso e Ossos/anatomia & histologia , Dióxido de Carbono/química , Linguados/crescimento & desenvolvimento , Temperatura Alta , Concentração de Íons de Hidrogênio , Longevidade , Membrana dos Otólitos/anatomia & histologia , Pressão Parcial
4.
J Exp Biol ; 217(Pt 4): 518-25, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24523499

RESUMO

Little is known about the capacity of early life stages to undergo hypercapnic and thermal acclimation under the future scenarios of ocean acidification and warming. Here, we investigated a comprehensive set of biological responses to these climate change-related variables (2°C above winter and summer average spawning temperatures and ΔpH=0.5 units) during the early ontogeny of the squid Loligo vulgaris. Embryo survival rates ranged from 92% to 96% under present-day temperature (13-17°C) and pH (8.0) scenarios. Yet, ocean acidification (pH 7.5) and summer warming (19°C) led to a significant drop in the survival rates of summer embryos (47%, P<0.05). The embryonic period was shortened by increasing temperature in both pH treatments (P<0.05). Embryo growth rates increased significantly with temperature under present-day scenarios, but there was a significant trend reversal under future summer warming conditions (P<0.05). Besides pronounced premature hatching, a higher percentage of abnormalities was found in summer embryos exposed to future warming and lower pH (P<0.05). Under the hypercapnic scenario, oxygen consumption rates decreased significantly in late embryos and newly hatched paralarvae, especially in the summer period (P<0.05). Concomitantly, there was a significant enhancement of the heat shock response (HSP70/HSC70) with warming in both pH treatments and developmental stages. Upper thermal tolerance limits were positively influenced by acclimation temperature, and such thresholds were significantly higher in late embryos than in hatchlings under present-day conditions (P<0.05). In contrast, the upper thermal tolerance limits under hypercapnia were higher in hatchlings than in embryos. Thus, we show that the stressful abiotic conditions inside the embryo's capsules will be exacerbated under near-future ocean acidification and summer warming scenarios. The occurrence of prolonged embryogenesis along with lowered thermal tolerance limits under such conditions is expected to negatively affect the survival success of squid early life stages during the summer spawning period, but not winter spawning.


Assuntos
Decapodiformes/fisiologia , Embrião não Mamífero/fisiologia , Água do Mar/química , Temperatura , Aclimatação , Animais , Mudança Climática , Decapodiformes/embriologia , Desenvolvimento Embrionário , Resposta ao Choque Térmico , Concentração de Íons de Hidrogênio , Larva/crescimento & desenvolvimento , Larva/fisiologia , Oceanos e Mares , Consumo de Oxigênio , Estações do Ano
5.
Proc Biol Sci ; 280(1768): 20131695, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-23926158

RESUMO

The combined effects of future ocean acidification and global warming on the hypoxia thresholds of marine biota are, to date, poorly known. Here, we show that the future warming and acidification scenario led to shorter embryonic periods, lower survival rates and the enhancement of premature hatching in the cuttlefish Sepia officinalis. Routine metabolic rates increased during the embryonic period, but environmental hypercapnia significantly depressed pre-hatchling's energy expenditures rates (independently of temperature). During embryogenesis, there was also a significant rise in the carbon dioxide partial pressure in the perivitelline fluid (PVF), bicarbonate levels, as well as a drop in pH and oxygen partial pressure (pO2). The critical partial pressure (i.e. hypoxic threshold) of the pre-hatchlings was significantly higher than the PVF oxygen partial pressure at the warmer and hypercapnic condition. Thus, the record of oxygen tensions below critical pO2 in such climate scenario indicates that the already harsh conditions inside the egg capsules are expected to be magnified in the years to come, especially in populations at the border of their thermal envelope. Such a scenario promotes untimely hatching and smaller post-hatching body sizes, thus challenging the survival and fitness of early life stages.


Assuntos
Hipóxia Celular , Decapodiformes/fisiologia , Animais , Dióxido de Carbono/metabolismo , Mudança Climática , Decapodiformes/embriologia , Desenvolvimento Embrionário , Metabolismo Energético , Concentração de Íons de Hidrogênio , Oceanos e Mares , Pressão Parcial , Temperatura
6.
Sci Total Environ ; 904: 166893, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37696409

RESUMO

Seahorses are one of the most unique and enigmatic animals, recognized as flagship species for several conservation issues. Unfortunately, seahorses' populations have been declining and their unique lifestyle may constrain the ability of these animals to evolve in the future climate scenarios. They inhabit shallow coastal waters that display daily or seasonal environmental fluctuations. Yet, few studies have scrutinized the impacts of climate changes on these iconic species. Within this context, the objective of this work was to test the effects of an extreme hypoxia exposure (~27 % dissolved oxygen for approximately 7 h) on the metabolism, behaviour and food intake of the temperate seahorse Hippocampus hippocampus. Regarding metabolism, hypoxia exposure led to a significant reduction in metabolic rates and an increase in ventilation rates. Seahorses showed signs of movement lethargy under oxygen depletion. The results show that a small but extreme exposure to hypoxia is tolerable by seahorses despite inducing metabolic and behavioural changes, that may jeopardize the future development and survival of these iconic organisms.


Assuntos
Smegmamorpha , Animais , Hipóxia/veterinária
7.
J Exp Zool A Ecol Integr Physiol ; 333(2): 126-132, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31793756

RESUMO

Atmospheric CO2 levels have been rising due to an increase in anthropic activities and its implications over marine ecosystems are unprecedented. The present study focused on the effects of ocean acidification (OA) on key hematological parameters of the juvenile small-spotted catsharks (Scyliorhinus canicula). Eggs were reared throughout the entire embryogenesis (~4 months) plus 5 additional months, in two experimental treatments (control: pCO2 ~ 400 µatm; and high CO2 : pCO2 ~ 900 µatm, Δ -0.3 pH units). After blood collection, the following hematological parameters were evaluated: (a) normal blood cells count (erythrocytes, leukocytes, and thrombocytes), (b) presence of erythrocytes with nuclear abnormalities, and (c) erythrocyte nucleus to cytoplasmic ratio. Concomitantly, to determine the cardiac and hematopoietic conditions, the spleen and heart to body ratios were also assessed. The present findings indicate that the measured variables may not be affected by elevated pCO2 in this temperate species, as no significant differences were observed between treatments across all the endpoints tested. Nonetheless, it is worth mentioning a decreasing trend observed in a number of thrombocytes associated with OA, which should foster further investigation, regarding other aspects of their coagulation response. Along with OA, other stressors are expected to impact marine life, such as warming and hypoxia. Thus, future research should aim to investigate the cumulative effect of these stressors on hematological parameters in sharks.


Assuntos
Dióxido de Carbono/efeitos adversos , Tubarões/sangue , Animais , Contagem de Células Sanguíneas , Plaquetas , Eritrócitos Anormais , Coração , Tamanho do Órgão , Água do Mar/química , Tubarões/embriologia , Baço
8.
Front Physiol ; 10: 975, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31404314

RESUMO

The oceanic uptake of carbon dioxide (CO2) is increasing and changing the seawater chemistry, a phenomenon known as ocean acidification (OA). Besides the expected physiological impairments, there is an increasing evidence of detrimental OA effects on the behavioral ecology of certain marine taxa, including cephalopods. Within this context, the main goal of this study was to investigate, for the first time, the OA effects (∼1000 µatm; ΔpH = 0.4) in the development and behavioral ecology (namely shelter-seeking, hunting and response to a visual alarm cue) of the common cuttlefish (Sepia officinalis) early life stages, throughout the entire embryogenesis until 20 days after hatching. There was no evidence that OA conditions compromised the cuttlefish embryogenesis - namely development time, hatching success, survival rate and biometric data (length, weight and Fulton's condition index) of newly hatched cuttlefish were similar between the normocapnic and hypercapnic treatments. The present findings also suggest a certain behavioral resilience of the cuttlefish hatchlings toward near-future OA conditions. Shelter-seeking, hunting and response to a visual alarm cue did not show significant differences between treatments. Thus, we argue that cuttlefishes' nekton-benthic (and active) lifestyle, their adaptability to highly dynamic coastal and estuarine zones, and the already harsh conditions (hypoxia and hypercapnia) inside their eggs provide a degree of phenotypic plasticity that may favor the odds of the recruits in a future acidified ocean. Nonetheless, the interacting effects of multiple stressors should be further addressed, to accurately predict the resilience of this ecologically and economically important species in the oceans of tomorrow.

9.
Cell Stress Chaperones ; 23(5): 1093-1100, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29948929

RESUMO

Atmospheric concentration of carbon dioxide (CO2) is increasing at an unprecedented rate and subsequently leading to ocean acidification. Concomitantly, ocean warming is intensifying, leading to serious and predictable biological impairments over marine biota. Reef-building corals have proven to be very vulnerable to climate change, but little is known about the resilience of non-reef-building species. In this study, we investigated the effects of ocean warming and acidification on the antioxidant enzyme activity (CAT-catalase, and GST-glutathione S-transferase), lipid peroxidation (using malondialdehyde, MDA-levels as a biomarker) and heat shock response (HSP70/HSC70 content) of the octocoral Veretillum cynomorium. After 60 days of acclimation, no mortalities were registered in all treatments. Moreover, CAT and GST activities, as well as MDA levels, did not change significantly under warming and/or acidification. Heat shock response was significantly enhanced under warming, but high CO2 did not have a significant effect. Contrasting to many of their tropical coral-reef relatives, our findings suggest that temperate shallow-living octocorals may be able to physiologically withstand future conditions of increased temperature and acidification.


Assuntos
Aclimatação , Antozoários/metabolismo , Temperatura Alta , Animais , Antozoários/enzimologia , Catalase/metabolismo , Mudança Climática , Glutationa Transferase/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Resposta ao Choque Térmico , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos , Oceanos e Mares
10.
Sci Total Environ ; 618: 388-398, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29132006

RESUMO

Increases in carbon dioxide (CO2) and other greenhouse gases emissions are changing ocean temperature and carbonate chemistry (warming and acidification, respectively). Moreover, the simultaneous occurrence of highly toxic and persistent contaminants, such as methylmercury, will play a key role in further shaping the ecophysiology of marine organisms. Despite recent studies reporting mostly additive interactions between contaminant and climate change effects, the consequences of multi-stressor exposure are still largely unknown. Here we disentangled how Argyrosomus regius physiology will be affected by future stressors, by analysing organ-dependent mercury (Hg) accumulation (gills, liver and muscle) within isolated/combined warming (ΔT=4°C) and acidification (ΔpCO2=1100µatm) scenarios, as well as direct deleterious effects and phenotypic stress response over multi-stressor contexts. After 30days of exposure, although no mortalities were observed in any treatments, Hg concentration was enhanced under warming conditions, especially in the liver. On the other hand, elevated CO2 decreased Hg accumulation and consistently elicited a dampening effect on warming and contamination-elicited oxidative stress (catalase, superoxide dismutase and glutathione-S-transferase activities) and heat shock responses. Thus, potentially unpinned on CO2-promoted protein removal and ionic equilibrium between hydrogen and reactive oxygen species, we found that co-occurring acidification decreased heavy metal accumulation and contributed to physiological homeostasis. Although this indicates that fish can be physiologically capable of withstanding future ocean conditions, additional experiments are needed to fully understand the biochemical repercussions of interactive stressors (additive, synergistic or antagonistic).


Assuntos
Peixes/fisiologia , Mercúrio/análise , Água do Mar/química , Estresse Fisiológico , Ácidos/química , Animais , Organismos Aquáticos , Dióxido de Carbono/análise , Mudança Climática , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análise
11.
Rev Bras Enferm ; 59(6): 780-6, 2006.
Artigo em Português | MEDLINE | ID: mdl-17469486

RESUMO

This study describes some reflections on the representations of nurses about themselves and about nursing, in order to analyze them within a psychoanalytic framework of the constitution of the subject in the sphere of the desire which motivates them, at the levels of the imaginary and the symbolic. The analysis adopted was the discursive practices proposed by Spink, using association of ideas in the hermeneutical tradition. Considering the subject, eight nurses were interviewed whose interpretations were displayed on graphs and tables. From discourse analysis emerged meanings in the symbolic sphere and the production of meanings. It is possible to understand that the desire of the nurse shows itself as the desire of others' desire, an imaginary desire and therefore, it is imaginary and to be constituted. This object which appears identified with the self, may appear over-valued or commonplace, depreciated or punished. From this point of view, new horizons may open up in practice and professional training for nurses, which brings them together around a signifier which can give them a meaning, enabling them to see themselves as subjects in their professional expressiveness.


Assuntos
Enfermeiras e Enfermeiros/psicologia , Enfermagem , Interpretação Psicanalítica , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Conserv Physiol ; 4(1): cow017, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293764

RESUMO

Small pelagic fishes are known to respond rapidly to changes in ocean climate. In this study, we evaluate the effects of future environmental warming (+2°C) during the early ontogeny of the European sardine, Sardina pilchardus. Warming reduced the survival of 30-day-old larvae by half. Length at hatching increased with temperature as expected, but no significant effect was observed on the length and growth at 30 days post-hatching. Warming did not significantly affect the thermal tolerance of sardine larvae, even though the mean lethal temperature increased by 1°C. In the warm conditions, sardine larvae showed signs of thermal stress, indicated by a pronounced increase in larval metabolism (Q 10 = 7.9) and a 45% increase in the heat shock response. Lipid peroxidation was not significantly affected by the higher temperature, even though the mean value doubled. Warming did not affect the time larvae spent swimming, but decreased by 36% the frequency of prey attacks. Given the key role of these small pelagics in the trophic dynamics off the Western Iberian upwelling ecosystem, the negative effects of warming on the early stages may have important implications for fish recruitment and ecosystem structure.

13.
Conserv Physiol ; 3(1): cov009, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27293694

RESUMO

Seahorses are currently facing great challenges in the wild, including habitat degradation and overexploitation, and how they will endure additional stress from rapid climate change has yet to be determined. Unlike most fishes, the poor swimming skills of seahorses, along with the ecological and biological constraints of their unique lifestyle, place great weight on their physiological ability to cope with climate changes. In the present study, we evaluate the effects of ocean warming (+4°C) and acidification (ΔpH = -0.5 units) on the physiological and behavioural ecology of adult temperate seahorses, Hippocampus guttulatus. Adult seahorses were found to be relatively well prepared to face future changes in ocean temperature, but not the combined effect of warming and acidification. Seahorse metabolism increased normally with warming, and behavioural and feeding responses were not significantly affected. However, during hypercapnia the seahorses exhibited signs of lethargy (i.e. reduced activity levels) combined with a reduction of feeding and ventilation rates. Nonetheless, metabolic rates were not significantly affected. Future ocean changes, particularly ocean acidification, may further threaten seahorse conservation, turning these charismatic fishes into important flagship species for global climate change issues.

14.
PLoS One ; 10(7): e0134082, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26221723

RESUMO

Until now, it is not known how the antioxidant and digestive enzymatic machinery of fish early life stages will change with the combined effects of future ocean acidification and warming. Here we show that high pCO2 (~1600 µatm) significantly decreased metabolic rates (up to 27.4 %) of flatfish larvae, Solea senegalensis, at both present (18 °C) and warmer temperatures (+4 °C). Moreover, both warming and hypercapnia increased the heat shock response and the activity of antioxidant enzymes, namely catalase (CAT) and glutathione S-transferase (GST), mainly in post-metamorphic larvae (30 dph). The lack of changes in the activity of CAT and GST of pre-metamorphic larvae (10 dph) seems to indicate that earlier stages lack a fully-developed antioxidant defense system. Nevertheless, the heat shock and antioxidant responses of post-metamorphic larvae were not enough to avoid the peroxidative damage, which was greatly increased under future environmental conditions. Digestive enzymatic activity of S. senegalensis larvae was also affected by future predictions. Hypercapnic conditions led to a decrease in the activity of digestive enzymes, both pancreatic (up to 26.1 % for trypsin and 74.5 % for amylase) and intestinal enzymes (up to 36.1 % for alkaline phosphatase) in post-metamorphic larvae. Moreover, the impact of ocean acidification and warming on some of these physiological and biochemical variables (namely, lower OCR and higher HSP and MDA levels) were translated into larvae performance, being significantly correlated with decreased larval growth and survival or increased incidence of skeletal deformities. The increased vulnerability of flatfish early life stages under future ocean conditions is expected to potentially determine recruitment and population dynamics in marine ecosystems.


Assuntos
Digestão , Linguados/metabolismo , Estresse Oxidativo , Água do Mar , Animais , Antioxidantes/metabolismo , Linguados/fisiologia , Aquecimento Global , Resposta ao Choque Térmico , Larva/enzimologia , Larva/metabolismo , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Consumo de Oxigênio
15.
J Comp Physiol B ; 184(1): 55-64, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24100467

RESUMO

The ability to understand and predict the effects of ocean warming (under realistic scenarios) on marine biota is of paramount importance, especially at the most vulnerable early life stages. Here we investigated the impact of predicted environmental warming (+3 °C) on the development, metabolism, heat shock response and antioxidant defense mechanisms of the early stages of the common octopus, Octopus vulgaris. As expected, warming shortened embryonic developmental time by 13 days, from 38 days at 18 °C to 25 days at 21 °C. Concomitantly, survival decreased significantly (~29.9 %). Size at hatching varied inversely with temperature, and the percentage of smaller premature paralarvae increased drastically, from 0 % at 18 °C to 17.8 % at 21 °C. The metabolic costs of the transition from an encapsulated embryo to a free planktonic form increased significantly with warming, and HSP70 concentrations and glutathione S-transferase activity levels were significantly magnified from late embryonic to paralarval stages. Yet, despite the presence of effective antioxidant defense mechanisms, ocean warming led to an augmentation of malondialdehyde levels (an indicative of enhanced ROS action), a process considered to be one of the most frequent cellular injury mechanisms. Thus, the present study provides clues about how the magnitude and rate of ocean warming will challenge the buffering capacities of octopus embryos and hatchlings' physiology. The prediction and understanding of the biochemical and physiological responses to warmer temperatures (under realistic scenarios) is crucial for the management of highly commercial and ecologically important species, such as O. vulgaris.


Assuntos
Embrião não Mamífero/fisiologia , Aquecimento Global , Octopodiformes/fisiologia , Animais , Desenvolvimento Embrionário , Glutationa Transferase/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Oceanos e Mares , Oxigênio/metabolismo
16.
PLoS One ; 7(6): e38282, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22701620

RESUMO

BACKGROUND: The knowledge about the capacity of organisms' early life stages to adapt to elevated temperatures is very limited but crucial to understand how marine biota will respond to global warming. Here we provide a comprehensive and integrated view of biological responses to future warming during the early ontogeny of a keystone invertebrate, the squid Loligo vulgaris. METHODOLOGY/PRINCIPAL FINDINGS: Recently-spawned egg masses were collected and reared until hatching at present day and projected near future (+2°C) temperatures, to investigate the ability of early stages to undergo thermal acclimation, namely phenotypic altering of morphological, behavioural, biochemical and physiological features. Our findings showed that under the projected near-future warming, the abiotic conditions inside the eggs promoted metabolic suppression, which was followed by premature hatching. Concomitantly, the less developed newborns showed greater incidence of malformations. After hatching, the metabolic burst associated with the transition from an encapsulated embryo to a planktonic stage increased linearly with temperature. However, the greater exposure to environmental stress by the hatchlings seemed to be compensated by physiological mechanisms that reduce the negative effects on fitness. Heat shock proteins (HSP70/HSC70) and antioxidant enzymes activities constituted an integrated stress response to ocean warming in hatchlings (but not in embryos). CONCLUSIONS/SIGNIFICANCE: The stressful abiotic conditions inside eggs are expected to be aggravated under the projected near-future ocean warming, with deleterious effects on embryo survival and growth. Greater feeding challenges and the lower thermal tolerance limits of the hatchlings are strictly connected to high metabolic demands associated with the planktonic life strategy. Yet, we found some evidence that, in the future, the early stages might support higher energy demands by adjusting some cellular functional properties to increase their thermal tolerance windows.


Assuntos
Aclimatação/fisiologia , Desenvolvimento Embrionário , Metabolismo Energético/fisiologia , Loligo/anatomia & histologia , Loligo/embriologia , Temperatura , Análise de Variância , Animais , Arginina/análogos & derivados , Arginina/metabolismo , Oceano Atlântico , Catalase/metabolismo , Embrião não Mamífero/embriologia , Glutationa Transferase/metabolismo , Proteínas de Choque Térmico/metabolismo , Peroxidação de Lipídeos , Loligo/metabolismo , Estresse Oxidativo/fisiologia , Consumo de Oxigênio/fisiologia , Superóxido Dismutase/metabolismo , Taxa de Sobrevida
17.
Comp Biochem Physiol B Biochem Mol Biol ; 161(2): 178-87, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22100702

RESUMO

The objectives of the present work were to investigate the temporal variation in the fatty acid (FA) composition of the octocoral Veretillum cynomorium, examine the effects of reproduction and environmental factors on FA variation, and establish a chemotaxonomic identification for this species. Mean oocyte size-frequency distributions showed that the majority of the oocytes had an intermediate size (Group II) before spawning (April and June). The late-vitellogenic oocytes (Group III) became absent in August and October and, during this post-spawning period, oocytes were primarily of small size (Group I). Most of the major FA, 16:0, 18:0, 20:4n-6, 20:5n-3, and the tetracosapolyenoic fatty acid (TPA), 24:6n-3, varied significantly throughout the year (p<0.01), with two peaks in August/October and February. The boost in early oogenesis, also associated with warmer temperatures, seemed to be responsible for the observed increase in FA content between June and August. The highest values of FA content were observed in February when intermediate oogenesis (Group II) was at its peak and there were considerable levels of available food in the environment. Also, the increase in food availability seemed to trigger the final stages of gametogenesis. The high quantity of 18:1n-7, odd-numbered and branched FAs, suggested the presence of a dynamic bacterial community in V. cynomorium, probably as an adaptive response to the lack of symbiotic microalgae. Although the presence of TPAs is the main feature distinguishing octocorals from other coral species, here we showed that there was no single FA clearly dominating the FA composition of V. cynomorium throughout the year. Instead, four main FAs share similar concentrations: 16:0, 20:4n-6, 20:5n-3 and 24:6n-3. The predominance of these four FAs combined with the higher amount of 24:6n-3 when compared to 24:5n-6 may serve as a chemotaxonomic feature to distinguish this octocoral species (or genus).


Assuntos
Antozoários/metabolismo , Ácidos Graxos/metabolismo , Animais , Tamanho Celular , Feminino , Oócitos/citologia , Oócitos/metabolismo , Oogênese , Reprodução , Salinidade , Estações do Ano , Água do Mar
18.
Acta Med Port ; 23(5): 837-40, 2010.
Artigo em Português | MEDLINE | ID: mdl-21144324

RESUMO

INTRODUCTION: Vaccination of pregnant women causes concerns both for themselves and for their healthcare providers. The main concern is the possibility of transmission of the virus/bacteria to the fetus in development. Due to obvious underlying ethical questions, clinical trials in this area are scarce and of difficult accomplishment. OBJECTIVES: The aim of this paper is to formulate proper guidance for vaccine Administration in pregnant women, particularly on cases of inadvertent administration, through the review of current evidence on live-attenuated vaccine administration in pregnant women. METHODOLOGY: Medline, Bandolier, The Cochrane Library and National Guideline Clearinghouse were searched using the following keywords (MeSH terms): vaccination AND pregnancy. The search was limited to articles published from January 2003 to December 2008. After exclusion of articles not concordant with the objectives of the review, 12 articles were selected (four review articles, two guidelines, one dissertation, the remaining were original articles), as well as the portuguese guidelines from Direcção Geral de Saúde (DGS) in what respects to vaccine administration. CONCLUSIONS: The contraindication of live-attenuated vaccine administration in pregnant women is based on the hypothetical/theoretical risk of potential negative effects for the developing fetus. Physicians should consider vaccinating pregnant women on the basis of the risks of vaccination versus the benefits of protection in each particular situation. Women should be told to avoid getting pregnant in the 28 days after liveattenuated vaccination. However, the inadvertent vaccination is not considered an indication for termination of the pregnancy.


Assuntos
Vacinação , Contraindicações , Feminino , Humanos , Gravidez
19.
São Paulo; s.n; 2011. 130 p.
Tese em Português | BDENF - enfermagem (Brasil), LILACS | ID: biblio-1146126

RESUMO

A proposta da pesquisa foi explorar a dimensão relacional existente no trabalho em saúde, tendo como foco as relações interpessoais desenvolvidas na Equipe de Saúde da Família ESF. Os objetivos do estudo buscaram: Analisar a dinâmica interacional na construção de lugares sociais a partir dos quais os integrantes de ESF e os gerentes buscam sustentação para o trabalho em equipe mapeando o Repertório Interpretativo e identificar os sentidos das práticas sociais mecanismos e linguagem em uso que contribuem para as interações sociais/relações interpessoais no trabalho em equipe. Trata-se de um estudo qualitativo de cunho exploratório, com bases teórico-metodológicas no construcionismo social. O estudo foi realizado em duas Unidades Básicas de Saúde (UBS) do Distrito Sanitário Leste da Secretária Municipal de Saúde do Município de Belo Horizonte, em dois momentos: de outubro de 2009 a fevereiro 2010 e de maio 2010 a agosto de 2010. Os dados foram coletados por meio de observação direta e entrevistas semi-estruturadas. Foram observadas 28 atividades integrativas das quatro ESF que atenderam aos critérios de inclusão deste estudo. Foram entrevistados 32 colaboradores, sendo: dois gerentes de UBS, quatro enfermeiros, três médicos, cinco Auxiliares de enfermagem e 18 Agentes Comunitários de Saúde (ACS). A análise dos dados nos deu a conhecer as características gerais dos colaboradores que articulados às entrevistas nos forneceram uma melhor compreensão dos processos relacionaisdesenvolvidos no contexto do trabalho em equipe das ESF. A análise dos discursos baseada na perspectiva construcionista social possibilitou identificar seis repertórios interpretativos: (a) espaço da reunião: o lugar do encontro das diversidades sociais; (b) Vivencias com os usuários: os momentos de choques de visão de mundos; (c) trabalhar em equipe: Falar é fácil, fazer é que são elas...; (d) As relações interpessoais e o desencontro entre a organização de trabalho e os trabalhadores; (e) os gerentes e os integrantes da ESF: o espaço existente; (f) espelho mágico: espelho, espelho meu...O uso dos repertórios permitiu justificar e legitimar as práticas sociais das relações interpessoais nas construções interacionais no contexto do trabalho da ESF, de diferentes maneiras, porém houve um predomínio na responsabilização de caráter individualista abstraída dos contextos sociais e anulada no trabalho, o qual é parcialmente isentado de suas responsabilidades. Os desempenhos sociais para a interação com o outro na construção de projetos comuns no cotidiano do trabalho são vividas de formas particularizadas. Entretanto, acreditamos serem importantes novas construções sobre os fazeres e dizeres das praticas relacionais no contexto do trabalho em saúde e em particular, no contexto do trabalho em equipe.


The aims of this study were to investigate the relational dimension within the healthcare work, focusing on interpersonal relations developed in a family health teamwork; to analyze the interactional dynamics in establishing social roles for the participants of the family health and the managers who support teamwork through mapping interpretative repertoire; to identify social practices-mechanisms and language in use - which contribute to social interactions/interpersonal relations in teamwork. It is an explorative qualitative study. Theoretically and methodologically, this research is based on social construcionism. The study was carried out in two Health Units in Belo Horizonte City in two periods: October 2009 to February 2010 and May 2010 to August 2010. Data was collected through observation and semi-structured interviews. Twenty-eight integrative activities of four family health teamworks (who met the criteria of the study were observed. Thirty-two collaborators were interviewed: two health unit managers, four nurses, three physicians, five nurse technicians and eighteen community health agents. Data showed the general characteristics of the collaborators who provided us a better understanding of the relational processes developed within family health teamwork settings. Speech analysis based on a construcionist approach allowed us to identify six interpretative repertoires:: (a) meeting place: the local where social diversity meet ; (b) Users share: a clash of pointsof view; (c) teamwork: It ain´t so easy to do; (d) Interpersonal relations and the gap between the Organization ( or Institution) and the workers; (e) The managers and the participants of the family health teamworks: the living space; (f) Magic mirror: mirror ,mirror on the wall The use of repertoires allowed us to justify and legitimate interpersonal relation practices within family health teamwork settings. However, there was a predominance in individualist responsibility character traits observed from social contexts and not present in the work settings, which is responsibility-free. The performance of social roles, for the interaction with others in building projects in common on a daily basis in a family health teamwork setting, are individually experienced. Nevertheless, we (strongly) believe them to be important and new relational practices in health-care work, especially teamwork.


Assuntos
Humanos , Pessoal de Saúde , Relações Interpessoais
20.
Rev. bras. enferm ; 59(6): 780-786, nov.-dez. 2006. tab
Artigo em Português | LILACS, BDENF - enfermagem (Brasil) | ID: lil-480313

RESUMO

Trata-se de reflexões das representações do enfermeiro sobre si e sobre enfermagem, dentro do referencial psicanalítico da constituição do sujeito no âmbito do desejo que o anima, nas instâncias do imaginário e do simbólico. A análise pautou-se pelas práticas discursivas de Spink, com a utilização de associações de idéias na tradição hermenêutica. Entrevistou-se oito enfermeiros cujas representações foram dispostas em gráficos e quadros. Da análise dos discursos emergiram significados, da esfera simbólica, de produção de sentido. Pode-se apreender que o desejo do enfermeiro se apresenta como desejo do desejo do outro, um desejo imaginário e por constituir-se. Esse objeto que se apresenta identificado ao eu pode-se apresentar idealizado, supervalorizado ou banalizado, depreciado ou punitivo. Nessa perspectiva, novos horizontes poderão se abrir no que tange à formação e à prática profissional do enfermeiro, portador de um sentido que lhes possibilitem perceberem-se como sujeitos na sua expressividade profissional.


This study describes some reflections on the representations of nurses about themselves and about nursing, in order to analyze them within a psychoanalytic framework of the constitution of the subject in the sphere of the desire which motivates them, at the levels of the imaginary and the symbolic. The analysis adopted was the discursive practices proposed by Spink, using association of ideas in the hermeneutical tradition. Considering the subject, eight nurses were interviewed whose interpretations were displayed on graphs and tables. From discourse analysis emerged meanings in the symbolic sphere and the production of meanings. It is possible to understand that the desire of the nurse shows itself as the desire of others' desire, an imaginary desire and therefore, it is imaginary and to be constituted. This object which appears identified with the self, may appear over-valued or commonplace, depreciated or punished. From this point of view, new horizons may open up in practice and professional training for nurses, which brings them together around a signifier which can give them a meaning, enabling them to see themselves as subjects in their professional expressiveness.


Se trata de reflexiones acerca de las representaciones del enfermero sobre si y la enfermería, adentro del referencial psicanalítico de la constituición del sujeto en el ámbito del deseo que lo anima, en las instancias del imaginario y del simbólico. El análisis adoptada fue de las prácticas discursivas propuesta por Spink, com la utilización de asociaciones de ideas en la tradición hermenéutica. Fueron entrevistados ocho enfermeros cuyas representaciones han sido puestas en gráficos y cuadros. Del análisis de los discursos surgieron significados de la esfera simbólica, de producción de sentido. Se puede aprehender que el deseo del enfermero se presenta como el deseo del deseo del outro, un deseo imaginario, y, por integrarse. Eso objeto que se apresenta identificado al yo, puede presentarse idealizado, supervalorado o banalizado, rebajado o punitivo. En esa perspectiva, nuevos horizontes podrán abrirse en lo que se refiere a la formación y la práctica profesional del enfermero, portador de um sentido que le dé la posibilidad de verse como sujetos en su expresividad profesional.


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/psicologia , Enfermagem , Interpretação Psicanalítica
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