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1.
Anal Chim Acta ; 1250: 340952, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36898809

RESUMO

The present work explores for the first time the potential of formic acid on the extraction of tiemannite (HgSe) nanoparticles from seabird tissues, in particular giant petrels. Mercury (Hg) is considered one of the top ten chemicals of major public health concern. However, the fate and metabolic pathways of Hg in living organisms remain unknown. Methylmercury (MeHg), largely produced by microbial activity in the aquatic ecosystems is biomagnified in the trophic web. HgSe is considered the end-product of MeHg demethylation in biota and an increasing number of studies focuses on the characterization of this solid compound to understand its biomineralization. In this study, a conventional enzymatic treatment is compared with a simpler and environmentally friendly extraction by using formic acid (5 mL of = 50 % formic acid) as exclusive reagent. The analyses by spICP-MS of the resulting extracts from a variety of seabird biological tissues (liver, kidneys, brain, muscle) reveal comparable results by both extraction approaches in terms of nanoparticles stability and extraction efficiency. Therefore, the results included in this work demonstrate the good performance of employing organic acid as simple, cost effective and green procedure to extract HgSe nanoparticles from animal tissues. Moreover, an alternative consisting of a classical enzymatic procedure but with ultrasonic assistance reducing the extraction time from 12 h to 2 min is also described for the first time. The sample processing methodologies developed, combined with spICP-MS, have emerged as powerful tools for the rapid screening and quantification of HgSe nanoparticles in animal tissues. Finally, this combination allowed us to identify the possible occurrence of Cd particles and As particles associated with HgSe NPs in seabirds.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Nanopartículas , Selênio , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Selênio/química , Poluentes Químicos da Água/análise , Mercúrio/análise
2.
Mar Pollut Bull ; 181: 113919, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35816822

RESUMO

Mercury is a pervasive environmental contaminant that can negatively impact seabirds. Here, we measure total mercury (THg) concentrations in red blood cells (RBCs) from breeding brown skuas (Stercorarius antarcticus) (n = 49) at Esperanza/Hope Bay, Antarctic Peninsula. The aims of this study were to: (i) analyse RBCs THg concentrations in relation to sex, year and stable isotope values of carbon (δ13C) and nitrogen (δ15N); and (ii) examine correlations between THg, body condition and breeding success. RBC THg concentrations were positively correlated with δ15N, which is a proxy of trophic position, and hence likely reflects the biomagnification process. Levels of Hg contamination differed between our study years, which is likely related to changes in diet and distribution. RBC THg concentrations were not related to body condition or breeding success, suggesting that Hg contamination is currently not a major conservation concern for this population.


Assuntos
Charadriiformes , Mercúrio , Poluentes Químicos da Água , Animais , Ecologia , Monitoramento Ambiental , Cadeia Alimentar , Isótopos/análise , Mercúrio/análise , Poluentes Químicos da Água/análise
3.
Sci Total Environ ; 768: 144373, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33454479

RESUMO

Despite the Antarctic Ocean being considered a pristine environment, elevated trace element concentrations have been reported in many marine organisms. The Antarctic Ocean is particularly vulnerable to climate change, which can also affect the bioaccumulation of trace element concentrations in biota. While Antarctic octopods are key components of the regional food webs as prey for a variety of predators (e.g., seals, fish, and seabirds), their contamination state by trace elements remains largely unknown. This study investigated the trace element concentrations in relation to the trophic ecology in Antarctic octopods. Stable isotope values (δ13C and δ15N) and trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V, and Zn) were measured in eight different species (Adelieledone polymorpha, Pareledone aequipapillae, P. albimaculata, P. aurata, P. charcoti, P. cornuta, P. felix, and P. turqueti) sampled near Elephant Island, close to the Antarctic Peninsula. Stable isotopes of δ15N varied among species, with significant differences between A. polymorpha and P. aurata suggesting potential niche segregation. Trace element concentrations also differed among species and with sampling depth, which likely reflects their trophic ecology. The data presented in this study provides the first insight into the trace element concentrations for these endemic octopods in this vulnerable habitat and their stable isotope values.


Assuntos
Oligoelementos , Poluentes Químicos da Água , Animais , Regiões Antárticas , Monitoramento Ambiental , Peixes , Cadeia Alimentar , Oligoelementos/análise , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 751: 141453, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32882547

RESUMO

Trace metals such as Cu, Hg, and Zn have been widely investigated in marine ecotoxicological studies considering their bioaccumulation, transfer along trophic webs, and the risks they pose to ecosystems and human health. Comparatively, Li has received little attention, although this element is increasingly used in the high-tech, ceramics/glass, and medication industries. Here, we report Li concentrations in more than 400 samples, including whole organisms and different organs of bivalves, cephalopods, crustaceans, and fish. We investigated species from three contrasting biogeographic areas, i.e. temperate (Bay of Biscay, northeast Atlantic Ocean), tropical (New Caledonia, Pacific Ocean), and subpolar climates (Kerguelen Islands, southern Indian Ocean), among diverse trophic groups (filter-feeders to meso-predators) and habitats (benthic, demersal, and pelagic). Although Li is homogeneously distributed in the ocean (at 0.18 µg/mL), Li concentrations in soft tissues vary greatly, from 0.01 to 1.20 µg/g dry weight. Multiple correspondence analyses reveal two clusters of high and low Li concentrations. Li distributions in marine organisms appear to be mostly geographically independent, though our results highlight a temperature dependency in fish muscles. Li is consistently bio-reduced through the trophic webs, with filter-feeders showing the highest concentrations and predatory fish the lowest. Strong variations are observed among organs, consistent with the biochemical similarity between Na and Li during transport in the brain and in osmoregulatory organs. Fish gills and kidneys show relatively high Li concentrations (0.26 and 0.15 µg/g, respectively) and fish brains show a large range of Li contents (up to 0.34 µg/g), whereas fish liver and muscles are Li depleted (0.07 ± 0.03 and 0.06 ± 0.08 µg/g, respectively). Altogether, these results provide the first exhaustive baseline for future Li ecotoxicology studies in marine coastal environments.


Assuntos
Organismos Aquáticos , Poluentes Químicos da Água , Animais , Oceano Atlântico , Ecossistema , Monitoramento Ambiental , Peixes , Cadeia Alimentar , Humanos , Oceano Índico , Lítio , Nova Caledônia , Oceano Pacífico , Inquéritos e Questionários , Poluentes Químicos da Água/análise
5.
Mar Environ Res ; 159: 104976, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32662429

RESUMO

The Chatham Rise, one of the highest offshore-primary production regions in New Zealand waters, hosts a great abundance and diversity of deep-sea cephalopods including the greater hooked squid, Moroteuthopsis ingens. Stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) and trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Se, V, and Zn) were assessed in female and male specimens of different size classes (89-563 mm mantle length). Values of δ13C and δ15N were overall higher in females and δ13C was further influenced by size and sex. Both muscular mantle (the largest fraction of the total body mass) and digestive gland (the known main storage organ for Ag, Cd, Cu and Zn in many cephalopods) tissues were analysed. Higher levels of Cd were observed in males than in females. A positive effect was found between size and Hg concentrations, which could be related to the ontogenetic descent of larger specimens into deeper waters, where they are exposed to higher Hg concentrations, and/or dietary shifts toward Hg-enriched prey with increasing size. This study provides trace element data for this abundant and ecologically important species, and further reveals higher trace element concentrations (especially Hg) in M. ingens from the Chatham Rise, compared to specimens from the sub-Antarctic zone.


Assuntos
Decapodiformes , Oligoelementos , Poluentes Químicos da Água , Animais , Regiões Antárticas , Monitoramento Ambiental , Feminino , Isótopos , Masculino , Nova Zelândia , Caracteres Sexuais
6.
Environ Pollut ; 256: 113389, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31685327

RESUMO

The boreoatlantic gonate squid (Gonatus fabricii) represents important prey for top predators-such as marine mammals, seabirds and fish-and is also an efficient predator of crustaceans and fish. Gonatus fabricii is the most abundant cephalopod in the northern Atlantic and Arctic Ocean but the trace element accumulation of this ecologically important species is unknown. In this study, trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn) were analysed from the mantle muscle and the digestive gland tissue of juveniles, adult females, and adult males that were captured south of Disko Island off West-Greenland. To assess the feeding habitat and trophic position of this species, stable isotopes of carbon (δ13C) and nitrogen (δ15N) were measured in their muscle tissue. Mercury concentrations were positively correlated with size (mantle length) and trophic position. The Hg/Se ratio was assessed because Se has been suggested to play a protective role against Hg toxicity and showed a molar surplus of Se relative to Hg. Cadmium concentrations in the digestive gland were negatively correlated with size and trophic position (δ15N), which suggested a dietary shift from Cd-rich crustaceans towards Cd-poor fish during ontogeny. This study provides trace element concentration data for G. fabricii from Greenlandic waters, which represents baseline data for a northern cephalopod species. Within West-Greenland waters, G. fabricii appears to be an important vector for the transfer of Cd in the Arctic pelagic food web.


Assuntos
Bioacumulação , Decapodiformes/metabolismo , Monitoramento Ambiental/métodos , Metais Pesados/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Regiões Árticas , Oceano Atlântico , Clima Frio , Ecossistema , Feminino , Cadeia Alimentar , Masculino , Metais Pesados/metabolismo , Alimentos Marinhos/análise , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo
7.
Enferm. univ ; 16(3): 240-248, jul.-sep. 2019. graf
Artigo em Espanhol | LILACS-Express | LILACS, BDENF - Enfermagem | ID: biblio-1090106

RESUMO

Resumen Introducción La homosexualidad representa fragmentar las normas establecidas socialmente, provenientes de una sociedad sectorizada, que adopta un patrón de obligatoriedad heteronormativa, por lo que una orientación sexual disidente conlleva enfrentar un sinfín de prejuicios, con afecciones significativas en el entorno familiar. Objetivo Conocer la respuesta del entorno familiar ante la revelación de la orientación sexual, desde el discurso de hombres homosexuales. Métodos Estudio cualitativo descriptivo, en el que se realizaron entrevistas semiestructuradas y observación participante a cinco hombres homosexuales de 19 a 36 años de edad de la ciudad de Puebla, México, a través de un muestreo teórico y el empleo de participantes clave para el acceso a los informantes. Resultados Los hallazgos se estructuraron en torno a una categoría central: respuesta familiar ante un integrante homosexual, de la cual se desprenden tres subcategorías: creencia familiar, conflicto familiar y proceso de pérdida familiar a la heteronormatividad, la cual se encuentra integrada por la agrupación de múltiples códigos, clasificados de acuerdo a las cinco etapas del proceso de pérdida, propuestas por Kübler-Ross. Discusión Las respuestas familiares ante la homosexualidad son dinámicas, sumergidas en un proceso de negación que con el tiempo puede llegar a la aceptación. Conclusiones Las respuestas familiares desencadenadas por la homosexualidad se expresan de forma multifacética y a manera de proceso; el conocimiento de éstas puede ayudar a guiar el actuar de enfermería y del equipo de salud, para planear actividades y estrategias ante el proceso de pérdida familiar de la heteronormatividad.


Abstract Introduction Homosexuality represents a deviation from the social norms established by a sectorial society which imposes having a mandatory heterosexual pattern. Because of this, having a different sexual orientation implies facing prejudices which have diverse impacts on the family environment. Objective To know the response of the family environment towards the revelation of the sexual orientation from the perspective of homosexual males. Methods This is a qualitative and descriptive study with theoretical sampling and key informing, which used semi-structured interviews and observations on five homosexual males from the city of Puebla, Mexico, whose ages ranged from 19 to 36 years old. Results: The findings clustered around a central category: the family response towards having a homosexual member, from which three subcategories emerged: family beliefs, family conflict, and the loss of the heterosexual normativity, reflected by multiple codes classified in the five stages of the process of a loss proposed by Kübler-Ross. Discussion: The family responses towards homosexuality are dynamic and framed by a denial process which eventually can lead to the acceptance. Conclusions: The family responses towards having a member being homosexual are multiple; thus, an understanding of these responses can help nurses and other health professionals to plan activities and strategies aimed at addressing the process of the family loss of the heterosexual normativity.


Resumo Introdução A homossexualidade representa fragmentar as normas estabelecidas socialmente, provenientes de uma sociedade setorizada, que adopta um padrão de obrigatoriedade heteronormativa, pelo que uma orientação sexual dissidente faz enfrentar uma infinidade de preconceitos, com afecções significativas no entorno familiar. Objetivo Conhecer a resposta do entorno familiar perante a revelação da orientação sexual, desde o discurso de homens homossexuais. Métodos Estudo qualitativo descritivo, no qual se realizaram entrevistas semiestruturadas e observação participante a cinco homens homossexuais de 19 a 36 anos de idade da cidade de Puebla, México, a través de uma amostragem teórica e o emprego de participantes chave para o acesso aos informantes. Resultados Os achados estruturaram-se em volta de uma categoria central: resposta familiar frente a um integrante homossexual, da qual se desprendem três subcategorias: crença familiar, conflito familiar e processo de perda familiar à heteronormatividade, a qual se encontra integrada pela agrupação de múltiplos códigos, classificados de acordo com as cinco etapas do processo de perda, propostas por Kübler-Ross. Discussão As respostas familiares diante da homossexualidade são dinâmicas, submersas em um processo de negação que com o tempo pode chegar à aceitação. Conclusões As respostas familiares desatadas pela homossexualidade expressam-se de forma multifacetada e em forma de processo; o conhecimento destas pode ajudar a guiar o agir da enfermagem e da equipe de saúde, para planejar atividades e estratégias frente ao processo de perda familiar da heteronormatividade.

8.
Sci Total Environ ; 667: 208-221, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30831362

RESUMO

Metallic and organic pollutants constitute a serious threat for coral reef ecosystems, potentially affecting a great number of species interacting within complex trophodynamic processes. Pesticides, PCBs and trace elements were measured on coral reef communities of three Pacific islands (Moorea, Wallis and New Caledonia) in relation with δ15N values, a proxy of trophic level. Several potential sources of organic matter, benthic invertebrates and fish belonging to various trophic strategies were sampled at each island. Wallis and New Caledonia displayed, respectively, the highest concentrations of pesticides and trace elements. In the three islands, most trace element concentrations (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and V) decreased when δ15N was rising (i.e. bioreduction), whereas Hg and Se biomagnified with increasing δ15N values. Only few trace elements in some islands did not show any significant trend in relation with δ15N (i.e., Ag in New Caledonia, Zn in Wallis and As plus Zn in Moorea). PCBs concentrations showed a significant bioreduction in New Caledonia and in Moorea, but a significant biomagnification in Wallis. Aldrin and heptachlor were the only pesticides to show a similar significant bioreduction in the three islands. Other pesticides, such as chlordecone, diazinon, endosulfan I and II, heptachlor-epoxide A and B, lindane and pp'-DDE displayed contrasted patterns (e.g. chlordecone significantly biomagnified in New Caledonia, significantly bioreduced in Wallis and did not displayed any significant trend in Moorea). Finally, for unclear reasons, Moorea displayed only negative significant correlations between δ15N and all pesticides (except pp'-DDT). Our results highlight that trophic level, here assessed through δ15N values, is a good predictor of metallic trace elements biomagnification or bioreduction in coral reef organisms. However, at large spatial scale, trophic level relevance to predict pesticides and PCBs biomagnification or bioreduction should be considered with caution and studied in close relation with local characteristics.


Assuntos
Bass/metabolismo , Recifes de Corais , Cadeia Alimentar , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Organismos Aquáticos/metabolismo , Metais/metabolismo , Nova Caledônia , Compostos Orgânicos/metabolismo , Polinésia
9.
Chemosphere ; 214: 866-876, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30317167

RESUMO

Despite typically not being taken into account (usually in favour of the 'global distillation' process), the input of persistent organic pollutants (POPs) through biological activities can be indeed relevant at the local scale in terrestrial polar environments when seabird colonies are considered. Seabirds can bioaccumulate and biomagnify POPs, gather in large numbers and excrete on land during their reproductive season, thus making them locally as relevant secondary sources of POPs. The first part of this study indicated that these colonies act as so for several essential and non-essential trace elements, and this second part tests the same hypothesis concerning POPs using the very same samples. Lichens (n = 55), mosses (n = 58) and soil (n = 37) were collected from 13 locations in the South Shetlands Archipelago during the austral summers of 2013-14 and 2014-15. They were divided in colony (within the colony itself for soil and within and surrounding the colony for vegetation) and control (at least 150 m away from any colony interference) and analysed for POPs such as organochlorine pesticides, polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers and stable isotopes (C and N). Results showed that colonies act clearly as a secondary source for PCBs and likely for hexachlorobenzene. As in the first part, probable local sources other than the colonies themselves are hypothesised because of high concentrations found in control sites. Again, soil seemed the most adequate matrix for the intended purposes especially because of some particularities in the absorption of animal-derived organic matter by vegetation, pointed out by stable isotope analyses.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Poluentes Ambientais/química , Animais , Regiões Antárticas , Aves , Poluentes Ambientais/análise
10.
Nat Commun ; 9(1): 3474, 2018 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-30150763

RESUMO

Malaria is a fatal human parasitic disease transmitted by a mosquito vector. Although the evolution of within-host malaria virulence has been the focus of many theoretical and empirical studies, the vector's contribution to this process is not well understood. Here, we explore how within-vector resource exploitation would impact the evolution of within-host Plasmodium virulence. By combining within-vector dynamics and malaria epidemiology, we develop a mathematical model, which predicts that non-competitive parasitic resource exploitation within-vector restricts within-host parasite virulence. To validate our model, we experimentally manipulate mosquito lipid trafficking and gauge within-vector parasite development and within-host infectivity and virulence. We find that mosquito-derived lipids determine within-host parasite virulence by shaping development (quantity) and metabolic activity (quality) of transmissible sporozoites. Our findings uncover the potential impact of within-vector environment and vector control strategies on the evolution of malaria virulence.


Assuntos
Malária/parasitologia , Plasmodium/patogenicidade , Animais , Humanos , Malária/transmissão , Mosquitos Vetores/parasitologia , Virulência
11.
Ecotoxicol Environ Saf ; 163: 323-330, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30056346

RESUMO

The orange-back flying squid, Sthenoteuthis pteropus, plays an important role in the eastern tropical Atlantic Ocean (ETA) pelagic food web, as both predator and prey. Specimens of S. pteropus were caught off the Cape Verde Islands and concentrations of Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V, and Zn were measured in the digestive gland. Among the analysed elements, Cd showed the highest average concentration with values among the highest ever recorded in cephalopods. In addition to the digestive gland, Hg concentrations were also analysed in the buccal mass and mantle tissue. Among the three tissues, buccal mass showed the highest Hg concentrations. In females, Hg concentrations in the buccal mass were positively correlated with stable isotope ratios (δ13C and δ15N) and mantle length, showing both bioaccumulation with age and bioamplification along the trophic levels. High Cd and Hg concentrations in the digestive gland and muscle respectively would lead to elevated exposure of squid-eating top predators such as yellowfin tuna, swordfish or dolphinfish, which are commercially harvested for human consumption. This study provides a deeper understanding of the trace element contamination in an abundant and ecologically important, but poorly studied pelagic squid in the ETA.


Assuntos
Arsênio/análise , Decapodiformes , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Oceano Atlântico , Monitoramento Ambiental , Feminino , Cadeia Alimentar , Trato Gastrointestinal/química , Masculino
12.
Chemosphere ; 204: 535-547, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29684873

RESUMO

Global distillation is classically pointed as the biggest responsible for contaminant inputs in Polar ecosystems. Mercury (Hg) and other trace elements (TEs) also present natural sources, whereas the biologically mediated input is typically ignored. However, bioaccumulation and biomagnification combined with the fact that seabirds gather in large numbers into large colonies and excrete on land might represent an important local TEs input. A previous work suggested these colonies as sources of not only nutrients, but also organic contaminants. To evaluate a similar hypothesis for TEs, samples of lichen (n = 55), mosses (n = 58) and soil (n = 37) were collected in 13 locations within the South Shetlands Archipelago during the austral summers of 2013-14 and 2014-15. They were divided in: "colony" (within the colony itself for soil and bordering it for vegetation) and "control" (at least 50 m away from colony interference), analysed for TEs (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V, and Zn) and stable isotopes (C and N). In most cases, soil seems the best matrix to assess colonies as TEs sources, as it presented more differences between control/colony sites than vegetation. Colonies are clearly local sources of organic matter, Cd, Hg and likely of As, Se and Zn. Conversely, Co, Cr, Ni and Pb come presumably from other sources, natural or anthropogenic. In general, isotopes were more useful for interpreting vegetation data due to fractionation of absorbed animal-derived organic matter. Other local Hg sources could be inferred from high levels in control sites, location and wind patterns.


Assuntos
Aves/fisiologia , Ecossistema , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Oligoelementos/análise , Animais , Regiões Antárticas , Monitoramento Ambiental
13.
Med. intensiva ; 34(2): [1-7], 2017. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-883253

RESUMO

Introducción: Aproximadamente un 40% del tiempo que un paciente está en ventilación mecánica corresponde al proceso de destete. La tasa de falla de extubación planeada es del 2-25%. La reintubación y su demora se asocian a complicaciones que incrementan la tasa de mortalidad y de la estancia en las Unidades cerrada y hospitalaria. Objetivo: Conocer la tasa de falla de extubación y analizar las características de estos pacientes en la Terapia Intensiva de un Hospital universitario. Pacientes y Métodos: Se incluyeron pacientes >18 años que ingresaron en la Terapia Intensiva del Hospital de Clínicas "José de San Martín" entre junio de 2013 y mayo de 2014, que fueron extubados de forma planeada y recibieron ventilación mecánica invasiva, por lo menos, 12 horas. Resultados: Se analizaron 139 pacientes. La tasa de falla de extubación fue del 14,4%. El grupo que falló presentó una media de tiempo hasta la reintubación de 18,2 h (DE ± 13.4). La neumonía asociada a la ventilación mecánica fue mayor en el grupo de falla (p = 0,001), al igual que los días de ventilación mecánica (p = 0,05), la estancia en terapia intensiva (p = 0,05), la mortalidad en terapia intensiva (p = 0,008) y hospitalaria (p = 0,003). Conclusiones: La tasa de falla de extubación coincide con lo reportado en la bibliografía. Los pacientes que fallaron tuvieron tasas mayores de neumonía asociada a la ventilación mecánica, de días de ventilación mecánica, de estancia en terapia intensiva, y de mortalidad en terapia intensiva y hospitalaria (AU)


Introduction: Approximately 40% of the time that a patient is mechanically ventilated is dedicated to the weaning process. The failure rate of planned extubation is 2-25%. Reintubation delay and extubation failure are associated with poor clinical outcomes, including an increase in the mortality rate and prolonged hospital and Intensive Care Unit stay. Objective: To analyze the extubation failure rate and determine the impact of extubation failure on patient outcomes in a University Hospital. Patients and Methods: Patients >18 years old admitted to Hospital de Clínicas "José de San Martín", between June 2013 and May 2014, who have receive mechanic ventilation for more than 12 hours, and with planned extubation. Results: A total of 139 patients were studied. Extubation failure rate was 14.4%. The mean time to reintubation of the group that failed was 18.2 hours (SD ± 13.4). Mechanical ventilation-associated pneumonia was greater in the failure group (p = 0.001), as well as days with the mechanical ventilation (p = 0.05), the Intensive Care Unit stay (p = 0.05), the Intensive Care Unit mortality rate (p = 0.008) and the hospital mortality rate (p = 0.003). Conclusions: The extubation failure rate coincides with that reported in the literature. Patients who failed had greater rates of mechanical ventilation-associated pneumonia, mechanical ventilated days, intensive care unit stay, and Intensive Care Unit and hospital mortality (AU)


Assuntos
Humanos , Respiração Artificial , Desmame , Pneumonia , Intubação
14.
Sci Total Environ ; 514: 511-22, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25666833

RESUMO

Contaminant effects on defence responses of ecologically and economically important organisms, such as the Pacific oyster Crassostrea gigas, are likely to influence their ability to resist infectious diseases, particularly at the young stages. The aim of this study was to explore the potential relationships between organic contaminants accumulated in the soft tissues of juvenile oysters, defence responses and physiological condition. Oysters were transplanted during summer and winter periods in different sites in the Marennes-Oléron Bay, the first area of oyster production in France, and in the Gironde Estuary, the biggest estuary in Occidental Europe. Amongst the battery of biochemical and physiological biomarkers applied in the present work [superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), malondyaldehyde (MDA), catecholase, laccase and lysozyme in gills, digestive glands, mantle and haemolymph, glycogen, proteins and lipids in the digestive gland and the condition index at the whole-organism level], MDA and lysozyme in the digestive gland and SOD, GPx and laccase in plasma contributed in order to significantly discriminate the sites in which oysters bioaccumulated different levels of heavy polycyclic aromatic hydrocarbons (HPAHs), polychlorobiphenyls (PCBs), polybromodiphenylethers (PBDEs), dichlorodiphenyltrichloroethanes (DDTs) and lindane. These results strengthen the hypothesis that it is possible to differentiate sites depending on their contamination levels and biological effects by carrying out studies with transplanted juvenile oysters. In addition, correlations were found between antioxidant and immune-defence responses, and PAH and DDT body burdens in the first area of oyster production in France (the Marennes-Oléron Bay) and where considerable oyster mortalities have been reported. This result suggests that the presence of organic chemical contaminants in the Marennes-Oléron Bay may influence defence responses in juveniles of C. gigas, and, therefore, could influence their ability to resist infectious diseases.


Assuntos
Crassostrea/metabolismo , Monitoramento Ambiental , Poluentes Químicos da Água/metabolismo , Animais , Baías , Catalase/metabolismo , Estuários , França , Brânquias/metabolismo , Glutationa Peroxidase/metabolismo , Substâncias Perigosas , Malondialdeído/metabolismo , Muramidase/metabolismo , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Água do Mar
15.
Sci Total Environ ; 514: 500-10, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25440063

RESUMO

The aim of this study was to determine 1) the relevance of using the Pacific oyster Crassostrea gigas as a sentinel organism, at a juvenile stage, for polycyclic aromatic hydrocarbon (PAH) and persistent organic pollutant (polychlorobiphenyl, PCB, polybromodimethylether, PBDE, and organochlorine pesticide, OCP) contamination, 2) the potential levels of chemical organic contamination in the Marennes-Oléron Bay, and their potential sources and 3) the potential influence of physiological or environmental factors on contaminant body burdens in oysters. To this end, juvenile oysters purchased from an oyster hatchery were transplanted to a reference site, in Bouin, and to different transplantation sites in the Marennes-Oléron Bay, the first oyster production area in France, and in the Gironde Estuary, the biggest estuary in Occidental Europe. Transplantations were done during summer and winter. Whole oyster soft tissues from each site were analysed for PAHs, PCBs, PBDEs and OCPs. Results obtained with a transplantation period of 3months suggest that C. gigas, at the juvenile stage, is a relevant sentinel organism for short-term assessment of contamination for these contaminants. In addition, no significant effects of physiological factors on contaminant body burdens were observed. Principal component analysis revealed two distinct groups of contaminants (PAHs and OPCs, and PCBs and PBDEs) and three groups of sites: 1) the reference site, 2) Les Palles (LP) and Boyard (BOY) in winter and 3) all the other sites. The group of LP and BOY was clearly defined by the levels of PAHs and OCPs, suggesting higher levels of contamination of these chemical compounds on these sites, potentially due to local contamination sources. In addition, no relevant effects of physiological or environmental factors on contaminant body burdens were observed. Results suggest also a predominance of contaminants related to agricultural activities along the Marennes-Oléron Bay, and therefore, further studies on the presence of pesticides in this region should be considered.


Assuntos
Crassostrea/metabolismo , Monitoramento Ambiental , Poluentes Químicos da Água/metabolismo , Animais , Baías/química , Estuários , França , Hidrocarbonetos Clorados/metabolismo , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Água do Mar
16.
Sci Total Environ ; 505: 180-8, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25461020

RESUMO

Seabirds often have high loads of contaminants. These contaminants have endocrine disrupting properties but their relationships with some endocrine mechanisms are still poorly investigated in free-living organisms. This is the case for the stress response which shifts energy investment away from reproduction and redirects it towards survival. In birds, this stress response is achieved through a release of corticosterone and is also accompanied by a decrease in circulating prolactin, an anterior pituitary hormone widely involved in regulating parental cares. We measured blood concentrations of some legacy persistent organic pollutants (POPs) and mercury (Hg) and examined their relationships with the corticosterone and prolactin responses of known-age (9-46 years old) incubating snow petrels (Pagodroma nivea) to a standardized capture/handling stress protocol. In this Antarctic seabird, we also investigated whether high contaminant burden correlates with a higher occurrence of egg neglect, a frequently observed behavior in snow petrels. POPs and Hg were unrelated to age. Stress-induced corticosterone concentrations were positively related to POPs in both sexes, and stress-induced prolactin concentrations were negatively related to Hg in males. Egg-neglect behavior was not related to POPs burden, but males with higher Hg concentrations were more likely to neglect their egg. This suggests that in birds, relationships between age and contaminants are complex and that even low to moderate concentrations of POPs and Hg are significantly related to hormonal secretion. In this Antarctic species, exposure to legacy POPs and Hg could make individuals more susceptible to environmental stressors such as ongoing disturbances in Polar Regions.


Assuntos
Comportamento Animal/efeitos dos fármacos , Aves/fisiologia , Corticosterona/sangue , Poluentes Ambientais/toxicidade , Mercúrio/toxicidade , Prolactina/sangue , Estresse Fisiológico , Animais , Monitoramento Ambiental , Poluentes Ambientais/sangue , Feminino , Masculino , Mercúrio/sangue
17.
Artigo em Inglês | MEDLINE | ID: mdl-26737669

RESUMO

The emotion recognition systems have become important for the diversity of its applications. Several methodologies have been proposed based on how emotions are reflected in biological systems, such as facial expressions, the activity of the nervous system or the prosody of voice. The detection of emotions by voice processing is an approach that involves a noninvasive procedure that produces results with an acceptable rate of detection. In this work an algorithm for features extraction was developed, that efficiently classify different emotional states. Thus, emotions that have not been trained can be associated with a trained emotion both belonging to the same region of the valence-arousal plane.


Assuntos
Algoritmos , Nível de Alerta , Emoções , Voz/fisiologia , Nível de Alerta/fisiologia , Bases de Dados Factuais , Emoções/fisiologia , Humanos , Processamento de Sinais Assistido por Computador
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 1203-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26736482

RESUMO

Measurement of oxygen saturation is a noninvasive monitoring method that has had a major impact on patient care in both emergency and ambulatory situations. It is an important parameter in neonatology field, especially in newborn preterm births, and in anesthetic and surgical procedures.


Assuntos
Oxigênio/sangue , Humanos
19.
Ecology ; 95(4): 1075-86, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24933825

RESUMO

Although toxic chemicals constitute a major threat for wildlife, their effects have been mainly assessed at the individual level and under laboratory conditions. Predicting population-level responses to pollutants in natural conditions is a major and ultimate task in ecological and ecotoxicological research. The present study aims to estimate the effect of mercury (Hg) levels on future apparent survival rates and breeding performances. We used a long-term data set (-10 years) and recently developed methodological tools on two closely related Antarctic top predators, the South Polar Skua Catharacta maccormicki from Adélie Land and the Brown Skua C. lonnbergi from the Kerguelen Archipelago. Adult survival rates and breeding probabilities were not affected by Hg levels, but breeding success in the following year decreased with increasing Hg levels. Although South Polar Skuas exhibited much lower Hg levels than Brown Skuas, they suffered from higher Hg-induced breeding failure. This species difference could be attributed to an interaction between Hg and other environmental perturbations, including climate change and a complex cocktail of pollutants. By including Hg-dependent demographic parameters in population models, we showed a weak population decline in response to increasing Hg levels. This demographic decline was more pronounced in South Polar Skuas than in Brown Skuas. Hence, Hg exposure differently affects closely related species. The wide range of environmental perturbations in Antarctic regions could exacerbate the demographic responses to Hg levels. In that respect, we urge future population modeling to take into account the coupled effects of climate change and anthropogenic pollution to estimate population projections.


Assuntos
Charadriiformes/fisiologia , Mercúrio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Regiões Antárticas , Mudança Climática , Populus
20.
J Fish Biol ; 84(5): 1574-81, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24661179

RESUMO

Stable carbon (δ¹³C) and nitrogen (δ¹5N) isotopic values and total mercury (Hg) concentrations were analysed in muscle and liver of mothers and embryos of two aplacental shark species, Squalus megalops and Centrophorus moluccensis. Embryos of the two species had similar or lower isotopic values than their respective mothers, the only exception being for δ¹³C, which was higher in the liver of C. moluccensis embryos than in their mothers. Hg concentrations were systematically lower in embryos compared with their mothers suggesting a low transfer of this element in muscle and liver.


Assuntos
Embrião não Mamífero/química , Fígado/química , Mercúrio/análise , Músculos/química , Tubarões , Animais , Isótopos de Carbono/análise , Monitoramento Ambiental , Feminino , Isótopos de Nitrogênio/análise , Poluentes Químicos da Água/análise
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