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1.
Soc Sci Med ; 205: 17-25, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29631198

RESUMO

Anti-retroviral Therapy (ART) transformed HIV into a chronic disease but its individual and public health benefits depend on high levels of adherence. The large and rising number of people on ART, now also used as prevention, puts considerable strain on health systems and providers in low and middle as well as high-income countries, which are our focus here. Delivering effective adherence support is thus crucial but challenging, especially given the promotion of patient-centredness and shared decision making in HIV care. To illuminate the complexities of ART adherence support delivered in and through clinical encounters, we conducted a multi-disciplinary interpretative literature review. We reviewed and synthesized 82 papers published post 1997 (when ART was introduced) belonging to three bodies of literature: public health and psychological studies of ART communication; anthropological and sociological studies of ART; and conversation analytic studies of patient-centredness and shared decision-making. We propose three inter-related tensions which make patient-centredness particularly complex in this infectious disease context: achieving trust versus probing about adherence; patient-centredness versus reaching public health targets; and empowerment versus responsibilisation as 'therapeutic citizens'. However, there is a dearth of evidence concerning how precisely ART providers implement patient-centredness, shared-decision making in practice, and enact trust and therapeutic citizenship. We show how conversation analysis could lead to new, actionable insights in this respect.


Assuntos
Antirretrovirais/uso terapêutico , Comunicação , Adesão à Medicação/psicologia , Relações Médico-Paciente , Objetivos , Infecções por HIV/tratamento farmacológico , Humanos , Assistência Centrada no Paciente , Saúde Pública
2.
Mar Pollut Bull ; 128: 519-526, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29571404

RESUMO

The continued rise in atmospheric carbon dioxide (CO2) levels is driving climate change and temperature shifts at a global scale. CO2 Capture and Storage (CCS) technologies have been suggested as a feasible option for reducing CO2 emissions and mitigating their effects. However, before CCS can be employed at an industrial scale, any environmental risks associated with this activity should be identified and quantified. Significant leakage of CO2 from CCS reservoirs and pipelines is considered to be unlikely, however direct and/or indirect effects of CO2 leakage on marine life and ecosystem functioning must be assessed, with particular consideration given to spatial (e.g. distance from the source) and temporal (e.g. duration) scales at which leakage impacts could occur. In the current mesocosm experiment we tested the potential effects of CO2 leakage on macrobenthic assemblages by exposing infaunal sediment communities to different levels of CO2 concentration (400, 1000, 2000, 10,000 and 20,000 ppm CO2), simulating a gradient of distance from a hypothetic leakage, over short-term (a few weeks) and medium-term (several months). A significant impact on community structure, abundance and species richness of macrofauna was observed in the short-term exposure. Individual taxa showed idiosyncratic responses to acidification. We conclude that the main impact of CO2 leakage on macrofaunal assemblages occurs almost exclusively at the higher CO2 concentration and over short time periods, tending to fade and disappear at increasing distance and exposure time. Although under the cautious perspective required by the possible context-dependency of the present findings, this study contributes to the cost-benefit analysis (environmental risk versus the achievement of the intended objectives) of CCS strategies.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Dióxido de Carbono/análise , Sequestro de Carbono , Invertebrados/efeitos dos fármacos , Poluentes Químicos da Água/análise , Animais , Organismos Aquáticos/classificação , Biodiversidade , Relação Dose-Resposta a Droga , Ecossistema , Sedimentos Geológicos/química , Invertebrados/classificação , Noruega , Água do Mar/química
3.
J Exp Biol ; 217(Pt 14): 2499-508, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24803457

RESUMO

The distribution patterns of many species in the intertidal zone are partly determined by their ability to survive and recover from tidal emersion. During emersion, most crustaceans experience gill collapse, impairing gas exchange. Such collapse generates a state of hypoxemia and a hypercapnia-induced respiratory acidosis, leading to hyperlactaemia and metabolic acidosis. However, how such physiological responses to emersion are modified by prior exposure to elevated CO2 and temperature combinations, indicative of future climate change scenarios, is not known. We therefore investigated key physiological responses of velvet swimming crabs, Necora puber, kept for 14 days at one of four pCO2/temperature treatments (400 µatm/10°C, 1000 µatm/10°C, 400 µatm/15°C or 1000 µatm/15°C) to experimental emersion and recovery. Pre-exposure to elevated pCO2 and temperature increased pre-emersion bicarbonate ion concentrations [HCO3(-)], increasing resistance to short periods of emersion (90 min). However, there was still a significant acidosis following 180 min emersion in all treatments. The recovery of extracellular acid-base via the removal of extracellular pCO2 and lactate after emersion was significantly retarded by exposure to both elevated temperature and pCO2. If elevated environmental pCO2 and temperature lead to slower recovery after emersion, then some predominantly subtidal species that also inhabit the low to mid shore, such as N. puber, may have a reduced physiological capacity to retain their presence in the low intertidal zone, ultimately affecting their bathymetric range of distribution, as well as the structure and diversity of intertidal assemblages.


Assuntos
Braquiúros/metabolismo , Dióxido de Carbono/metabolismo , Temperatura Alta/efeitos adversos , Água do Mar/química , Acidose , Animais , Mudança Climática , Concentração de Íons de Hidrogênio , Hipercapnia , Ondas de Maré
4.
Environ Microbiol Rep ; 6(1): 113-21, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24596269

RESUMO

In marine environments, macrofauna living in or on the sediment surface may alter the structure, diversity and function of benthic microbial communities. In particular, microbial nitrogen (N)-cycling processes may be enhanced by the activity of large bioturbating organisms. Here, we study the effect of the burrowing mud shrimp Upogebia deltaura upon temporal variation in the abundance of genes representing key N-cycling functional guilds. The abundance of bacterial genes representing different N-cycling guilds displayed different temporal patterns in burrow sediments in comparison with surface sediments, suggesting that the burrow provides a unique environment where bacterial gene abundances are influenced directly by macrofaunal activity. In contrast, the abundances of archaeal ammonia oxidizers varied temporally but were not affected by bioturbation, indicating differential responses between bacterial and archaeal ammonia oxidizers to environmental physicochemical controls. This study highlights the importance of bioturbation as a control over the temporal variation in nitrogen-cycling microbial community dynamics within coastal sediments.


Assuntos
Archaea/metabolismo , Proteínas Arqueais/genética , Bactérias/metabolismo , Proteínas de Bactérias/genética , Ecossistema , Sedimentos Geológicos/microbiologia , Nitrogênio/metabolismo , Animais , Archaea/genética , Archaea/isolamento & purificação , Proteínas Arqueais/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Biodiversidade , Ciclo do Nitrogênio , Água do Mar/microbiologia
5.
Philos Trans R Soc Lond B Biol Sci ; 368(1627): 20120441, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23980243

RESUMO

Ocean acidification (OA), caused by the dissolution of increasing concentrations of atmospheric carbon dioxide (CO2) in seawater, is projected to cause significant changes to marine ecology and biogeochemistry. Potential impacts on the microbially driven cycling of nitrogen are of particular concern. Specifically, under seawater pH levels approximating future OA scenarios, rates of ammonia oxidation (the rate-limiting first step of the nitrification pathway) have been shown to dramatically decrease in seawater, but not in underlying sediments. However, no prior study has considered the interactive effects of microbial ammonia oxidation and macrofaunal bioturbation activity, which can enhance nitrogen transformation rates. Using experimental mesocosms, we investigated the responses to OA of ammonia oxidizing microorganisms inhabiting surface sediments and sediments within burrow walls of the mud shrimp Upogebia deltaura. Seawater was acidified to one of four target pH values (pHT 7.90, 7.70, 7.35 and 6.80) in comparison with a control (pHT 8.10). At pHT 8.10, ammonia oxidation rates in burrow wall sediments were, on average, fivefold greater than in surface sediments. However, at all acidified pH values (pH ≤ 7.90), ammonia oxidation rates in burrow sediments were significantly inhibited (by 79-97%; p < 0.01), whereas rates in surface sediments were unaffected. Both bacterial and archaeal abundances increased significantly as pHT declined; by contrast, relative abundances of bacterial and archaeal ammonia oxidation (amoA) genes did not vary. This research suggests that OA could cause substantial reductions in total benthic ammonia oxidation rates in coastal bioturbated sediments, leading to corresponding changes in coupled nitrogen cycling between the benthic and pelagic realms.


Assuntos
Amônia/metabolismo , Archaea/metabolismo , Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Microbiota/fisiologia , Água do Mar/química , Análise de Variância , Animais , Archaea/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Hemolinfa/química , Concentração de Íons de Hidrogênio , Oceanos e Mares , Oxirredução , Dinâmica Populacional
6.
Mar Pollut Bull ; 73(2): 416-27, 2013 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-23218873

RESUMO

A mesocosm experiment was conducted to quantify the relationships between the presence and body size of two burrowing heart urchins (Brissopsis lyrifera and Echinocardium cordatum) and rates of sediment nutrient flux. Furthermore, the impact of seawater acidification on these relationships was determined during this 40-day exposure experiment. Using carbon dioxide (CO2) gas, seawater was acidified to pHNBS 7.6, 7.2 or 6.8. Control treatments were maintained in natural seawater (pH≈8.0). Under normocapnic conditions, burrowing urchins were seen to reduce the sediment uptake of nitrite or nitrate whilst enhancing the release of silicate and phosphate. In acidified (hypercapnic) treatments, the biological control of biogeochemical cycles by urchins was significantly affected, probably through the combined impacts of high CO2 on nitrifying bacteria, benthic algae and urchin behaviour. This study highlights the importance of considering biological interactions when predicting the consequences of seawater acidification on ecosystem function.


Assuntos
Dióxido de Carbono/toxicidade , Ecossistema , Ouriços-do-Mar/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Dióxido de Carbono/análise , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Nitratos/análise , Fosfatos/análise , Água do Mar/química , Poluentes Químicos da Água/análise
7.
Fish Shellfish Immunol ; 30(6): 1209-22, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21463691

RESUMO

The inception of ecological immunology has led to an increase in the number of studies investigating the impact of environmental stressors on host immune defence mechanisms. This in turn has led to an increased understanding of the importance of invertebrate groups for immunological research. This review discusses the advances made within marine invertebrate ecological immunology over the past decade. By demonstrating the environmental stressors tested, the immune parameters typically investigated, and the species that have received the greatest level of investigation, this review provides a critical assessment of the field of marine invertebrate ecological immunology. In highlighting the methodologies employed within this field, our current inability to understand the true ecological significance of any immune dysfunction caused by environmental stressors is outlined. Additionally, a number of examples are provided in which studies successfully demonstrate a measure of immunocompetence through alterations in disease resistance and organism survival to a realized pathogenic threat. Consequently, this review highlights the potential to advance our current understanding of the ecological and evolutionary significance of environmental stressor related immune dysfunction. Furthermore, the potential for the advancement of our understanding of the immune system of marine invertebrates, through the incorporation of newly emerging and novel molecular techniques, is emphasized.


Assuntos
Ecossistema , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Imunidade Inata/imunologia , Invertebrados/imunologia , Estresse Fisiológico/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/imunologia , Biologia Marinha , Oceanos e Mares , Fagocitose/imunologia , Explosão Respiratória/imunologia , Especificidade da Espécie
8.
Environ Pollut ; 158(12): 3490-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20430496

RESUMO

An embryo development assay using a common test organism, the edible mussel (Mytilus galloprovincialis), exposed to both Fe(2)O(3) nanoparticles and soluble FeCl(3) at 3 acidic pHs, has provided evidence for the following: (1) CO(2) enriched seawater adjusted to pH projections for carbon capture leakage scenarios (CCS) significantly impaired embryo development; (2) under natural pH conditions, no significant effect was detected following exposure of embryos to Fe, no matter if in nano- or soluble form; (3) at pH of natural seawater nano-Fe particles aggregate into large, polydisperse and porous particles, with no biological impact detected; (4) at pH 6 and 7, such aggregates may moderate the damage associated with CO(2) enrichment as indicated by an increased prevalence of normal D-shell larvae when nano-Fe was present in the seawater at pH 7, while soluble iron benefited embryo development at pH 6, and (5) the observed effects of iron on pH-induced development toxicity were concentration dependent.


Assuntos
Dióxido de Carbono/química , Compostos Férricos/toxicidade , Mytilus/embriologia , Nanopartículas/toxicidade , Animais , Desenvolvimento Embrionário/fisiologia , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Mytilus/metabolismo , Nanopartículas/química , Água do Mar/química
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