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1.
Proc Natl Acad Sci U S A ; 121(9): e2319436121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38386712

RESUMO

Terrestrial enhanced weathering (EW) of silicate rocks, such as crushed basalt, on farmlands is a promising scalable atmospheric carbon dioxide removal (CDR) strategy that urgently requires performance assessment with commercial farming practices. We report findings from a large-scale replicated EW field trial across a typical maize-soybean rotation on an experimental farm in the heart of the United Sates Corn Belt over 4 y (2016 to 2020). We show an average combined loss of major cations (Ca2+ and Mg2+) from crushed basalt applied each fall over 4 y (50 t ha-1 y-1) gave a conservative time-integrated cumulative CDR potential of 10.5 ± 3.8 t CO2 ha-1. Maize and soybean yields increased significantly (P < 0.05) by 12 to 16% with EW following improved soil fertility, decreased soil acidification, and upregulation of root nutrient transport genes. Yield enhancements with EW were achieved with significantly (P < 0.05) increased key micro- and macronutrient concentrations (including potassium, magnesium, manganese, phosphorus, and zinc), thus improving or maintaining crop nutritional status. We observed no significant increase in the content of trace metals in grains of maize or soybean or soil exchangeable pools relative to controls. Our findings suggest that widespread adoption of EW across farming sectors has the potential to contribute significantly to net-zero greenhouse gas emissions goals while simultaneously improving food and soil security.


Assuntos
Silicatos , Oligoelementos , Zea mays , Agricultura , Solo , Dióxido de Carbono , Glycine max
2.
Echo Res Pract ; 10(1): 7, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37076874

RESUMO

Pregnancy is a dynamic process associated with profound hormonally mediated haemodynamic changes which result in structural and functional adaptations in the cardiovascular system. An understanding of the myocardial adaptations is important for echocardiographers and clinicians undertaking or interpreting echocardiograms on pregnant and post-partum women. This guideline, on behalf of the British Society of Echocardiography and United Kingdom Maternal Cardiology Society, reviews the expected echocardiographic findings in normal pregnancy and in different cardiac disease states, as well as echocardiographic signs of decompensation. It aims to lay out a structure for echocardiographic scanning and surveillance during and after pregnancy as well as suggesting practical advice on scanning pregnant women.

3.
BJOG ; 130(10): 1269-1274, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37039253

RESUMO

OBJECTIVE: Direct current cardioversion (DCCV) in pregnancy is rarely required and typically only documented in single case reports or case series. A recent UK confidential enquiry reported on several maternal deaths where appropriate DCCV appeared to have been withheld. DESIGN: Retrospective cohort study. SETTING: Seventeen UK and Ireland specialist maternity centres. SAMPLE: Twenty-seven pregnant women requiring DCCV in pregnancy. MAIN OUTCOME MEASURES: Maternal and fetal outcomes following DCCV. RESULTS: Twenty-seven women had a total of 29 DCCVs in pregnancy. Of these, 19 (70%) initial presentations were to Emergency Departments and eight (30%) to maternity settings. There were no maternal deaths. Seventeen of the women (63%) had a prior history of heart disease. Median gestation at DCCV was 28 weeks, median gestation at delivery was 35 weeks, with a live birth in all cases. The abnormal heart rhythms documented at the first cardioversion were atrial fibrillation in 12/27 (44%) cases, atrial flutter in 8/27 (30%), supraventricular tachycardia in 5/27 (19%) and atrial tachycardia in 2/27 (7%). Fetal monitoring was undertaken following DCCV on 14/29 (48%) occasions (10 of 19 (53%) at ≥26 weeks) and on 2/29 (7%) occasions, urgent delivery was required post DCCV. CONCLUSIONS: Direct current cardioversion in pregnancy is rarely required but should be undertaken when clinically indicated according to standard algorithms to optimise maternal wellbeing. Once the woman is stable post DCCV, gestation-relevant fetal monitoring should be undertaken. Maternity units should develop multidisciplinary processes to ensure pregnant women receive the same standard of care as their non-pregnant counterparts.


Assuntos
Fibrilação Atrial , Cardiopatias , Humanos , Feminino , Gravidez , Cardioversão Elétrica , Resultado do Tratamento , Estudos Retrospectivos
4.
J Parkinsons Dis ; 12(6): 1897-1915, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754287

RESUMO

BACKGROUND: Rodent Parkinson's disease (PD) models are valuable to interrogate neurobiological mechanisms of exercise that mitigate motor impairment. Translating these mechanisms to human PD must account for physical capabilities of the patient. OBJECTIVE: To establish cardiovascular parameters as a common metric for cross-species translation of aerobic exercise impact. METHOD: We evaluated aerobic exercise impact on heart rate (HR) in 21 early-stage PD subjects (Hoehn Yahr ≤1.5) exercising in non-contact boxing training for ≥3 months, ≥3x/week. In 4-month-old Pink1 knockout (KO) rats exercising in a progressively-increased treadmill speed regimen, we determined a specific treadmill speed that increased HR to an extent similar in human subjects. RESULTS: After completing aerobic exercise for ∼30 min, PD subjects had increased HR∼35% above baseline (∼63% maximum HR). Motor and cognitive test results indicated the exercising subjects completed the timed up and go (TUG) and trail-making test (TMT-A) in significantly less time versus exercise-naïve PD subjects. In KO and age-matched wild-type (WT) rats, treadmill speeds of 8-10 m/min increased HR up to 25% above baseline (∼67% maximum HR), with no further increases up to 16 m/min. Exercised KO, but not WT, rats showed increased locomotor activity compared to an age-matched exercise-naïve cohort at 5 months old. CONCLUSION: These proof-of-concept results indicate HR is a cross-species translation parameter to evaluate aerobic exercise impact on specific motor or cognitive functions in human subjects and rat PD models. Moreover, a moderate intensity exercise regimen is within the physical abilities of early-stage PD patients and is therefore applicable for interrogating neurobiological mechanisms in rat PD models.


Assuntos
Doença de Parkinson , Animais , Teste de Esforço , Terapia por Exercício/métodos , Frequência Cardíaca , Humanos , Lactente , Doença de Parkinson/genética , Ratos
5.
PLoS One ; 16(11): e0258851, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34788310

RESUMO

IMPORTANCE: Epidemiologists report a 56% increased risk of veterans with (+) mild traumatic brain injury (mTBI) developing Parkinson's disease (PD) within 12-years post-injury. The most relevant contributors to this high risk of PD in veterans (+) mTBI is unknown. As cognitive problems often precede PD diagnosis, identifying specific domains most involved with mTBI-related PD onset is critical. OBJECTIVES: To discern which cognitive domains underlie the mTBI-PD risk relationship proposed in epidemiology studies. DESIGN AND SETTING: This exploratory match-controlled, cross-sectional study was conducted in a medical school laboratory from 2017-2020. PARTICIPANTS: Age- and IQ-matched veterans with (+) and without mTBI, non-veteran healthy controls, and IQ-matched non-demented early-stage PD were compared. Chronic neurological, unremitted/debilitating diseases, disorders, dementia, and substance use among others were excluded. EXPOSURE: Veterans were or were not exposed to non-penetrating combat-related mTBI occurring within the past 7-years. No other groups had recent military service or mTBI. MAIN OUTCOMES / MEASURES: Cognitive flexibility, attention, memory, visuospatial ability, and verbal fluency were examined with well-known standardized neuropsychological assessments. RESULTS: Out of 200 volunteers, 114 provided evaluable data. Groups significantly differed on cognitive tests [F (21,299) = 3.09, p<0.0001]. Post hoc tests showed veterans (+) mTBI performed significantly worse than matched-control groups on four out of eight cognitive tests (range: p = .009 to .049), and more often than not performed comparably to early-stage PD (range: p = .749 to .140). CONCLUSIONS AND RELEVANCE: We found subtle, premature cognitive decline occurring in very specific cognitive domains in veterans (+) mTBI that would typically be overlooked in a clinic setting, This result potentially puts them at-risk for continual cognitive decline that may portend to the eventual onset of PD or some other neurodegenerative disease.


Assuntos
Concussão Encefálica/psicologia , Disfunção Cognitiva/etiologia , Doença de Parkinson/psicologia , Veteranos/psicologia , Idoso , Depressão/psicologia , Humanos , Pessoa de Meia-Idade , Transtornos de Estresse Pós-Traumáticos/psicologia
6.
J Parkinsons Dis ; 11(2): 405-419, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33361612

RESUMO

Up to 23% of newly diagnosed, non-demented, Parkinson's disease (PD) patients experience deficits in executive functioning (EF). In fact, EF deficits may occur up to 39-months prior to the onset of motor decline. Optimal EF requires working memory, attention, cognitive flexibility, and response inhibition underlying appropriate decision-making. The capacity for making strategic decisions requires inhibiting imprudent decisions and are associated with noradrenergic and dopaminergic signaling in prefrontal and orbitofrontal cortex. Catecholaminergic dysfunction and the loss of noradrenergic and dopaminergic cell bodies early in PD progression in the aforementioned cortical areas likely contribute to EF deficits resulting in non-strategic decision-making. Thus, detecting these deficits early in the disease process could help identify a significant portion of individuals with PD pathology (14-60%) before frank motor impairment. A task to evaluate EF in the domain of non-strategic decision-making might be useful to indicate the moderate loss of catecholamines that occurs early in PD pathology prior to motor decline and cognitive impairment. In this review, we focus on the potential utility of the Iowa Gambling Task (IGT) for this purpose, given significant overlap between in loss of dopaminergic and noradrenergic cells bodies in early PD and the deficits in catecholamine function associated with decreased EF. As such, given the loss of catecholamines already well-underway after PD diagnosis, we evaluate the potential utility of the IGT to identify the risk of therapeutic non-compliance and a potential companion approach to detect PD in premotor stages.


Assuntos
Jogo de Azar , Doença de Parkinson , Catecolaminas , Humanos , Testes Neuropsicológicos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico
8.
Nature ; 583(7815): 242-248, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641817

RESUMO

Enhanced silicate rock weathering (ERW), deployable with croplands, has potential use for atmospheric carbon dioxide (CO2) removal (CDR), which is now necessary to mitigate anthropogenic climate change1. ERW also has possible co-benefits for improved food and soil security, and reduced ocean acidification2-4. Here we use an integrated performance modelling approach to make an initial techno-economic assessment for 2050, quantifying how CDR potential and costs vary among nations in relation to business-as-usual energy policies and policies consistent with limiting future warming to 2 degrees Celsius5. China, India, the USA and Brazil have great potential to help achieve average global CDR goals of 0.5 to 2 gigatonnes of carbon dioxide (CO2) per year with extraction costs of approximately US$80-180 per tonne of CO2. These goals and costs are robust, regardless of future energy policies. Deployment within existing croplands offers opportunities to align agriculture and climate policy. However, success will depend upon overcoming political and social inertia to develop regulatory and incentive frameworks. We discuss the challenges and opportunities of ERW deployment, including the potential for excess industrial silicate materials (basalt mine overburden, concrete, and iron and steel slag) to obviate the need for new mining, as well as uncertainties in soil weathering rates and land-ocean transfer of weathered products.


Assuntos
Agricultura , Dióxido de Carbono/isolamento & purificação , Produtos Agrícolas , Sedimentos Geológicos/química , Aquecimento Global/prevenção & controle , Objetivos , Silicatos/química , Atmosfera/química , Brasil , China , Política Ambiental/economia , Política Ambiental/legislação & jurisprudência , Aquecimento Global/economia , Índia , Ferro/isolamento & purificação , Mineração , Política , Probabilidade , Silicatos/isolamento & purificação , Aço/isolamento & purificação , Temperatura , Fatores de Tempo , Estados Unidos
9.
Glob Chang Biol ; 26(6): 3658-3676, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32314496

RESUMO

Land-based enhanced rock weathering (ERW) is a biogeochemical carbon dioxide removal (CDR) strategy aiming to accelerate natural geological processes of carbon sequestration through application of crushed silicate rocks, such as basalt, to croplands and forested landscapes. However, the efficacy of the approach when undertaken with basalt, and its potential co-benefits for agriculture, require experimental and field evaluation. Here we report that amending a UK clay-loam agricultural soil with a high loading (10 kg/m2 ) of relatively coarse-grained crushed basalt significantly increased the yield (21 ± 9.4%, SE) of the important C4 cereal Sorghum bicolor under controlled environmental conditions, without accumulation of potentially toxic trace elements in the seeds. Yield increases resulted from the basalt treatment after 120 days without P- and K-fertilizer addition. Shoot silicon concentrations also increased significantly (26 ± 5.4%, SE), with potential benefits for crop resistance to biotic and abiotic stress. Elemental budgets indicate substantial release of base cations important for inorganic carbon removal and their accumulation mainly in the soil exchangeable pools. Geochemical reactive transport modelling, constrained by elemental budgets, indicated CO2 sequestration rates of 2-4 t CO2 /ha, 1-5 years after a single application of basaltic rock dust, including via newly formed soil carbonate minerals whose long-term fate requires assessment through field trials. This represents an approximately fourfold increase in carbon capture compared to control plant-soil systems without basalt. Our results build support for ERW deployment as a CDR technique compatible with spreading basalt powder on acidic loamy soils common across millions of hectares of western European and North American agriculture.


Assuntos
Solo , Sorghum , Agricultura , Dióxido de Carbono , Poeira , Grão Comestível , Silicatos
10.
Clin Med (Lond) ; 20(1): 92-94, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31704728

RESUMO

BACKGROUND: Isolated aortic infection is rare and is typically associated with an underlying aortic aneurysm or a prosthetic aortic graft. CASE SUMMARY: A 38-year-old woman was admitted with symptoms of left upper limb ischaemia and had imaging findings suggestive of thrombus extending from the ascending aorta into the subclavian and brachial arteries. She underwent evacuation of the aortic masses and replacement of the ascending aorta. Citrobacter koseri was isolated from the excised tissue and the patient received 6 weeks of appropriate antibiotic therapy. DISCUSSION: This is an unusual case of acute upper limb ischaemia due to a mass infected with Citrobacter koseri in the ascending aorta without heart valve involvement.


Assuntos
Arteriopatias Oclusivas , Citrobacter koseri , Trombose , Adulto , Antibacterianos/uso terapêutico , Aorta , Feminino , Humanos
12.
Clin Med (Lond) ; 19(1): 82-84, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30651254

RESUMO

A 63-year-old man with an extensive travel history to South East Asia presented with generalised malaise, temporal headaches and high inflammatory markers. He was treated with corticosteroids for presumed giant cell arteritis. Unsuccessful attempts to wean him from prednisolone prompted further investigations by rheumatology, haematology and finally ophthalmology. Roth spots were identified which prompted blood cultures to be taken. All three sets grew Streptococcus sinensis, an alpha-haemolytic Streptococcus reported as an emerging cause of endocarditis worldwide. The patient had signs of severe aortic regurgitation, confirmed on transthoracic echo. A transoesophageal echo demonstrated large aortic valve vegetations. He underwent an aortic valve replacement and completed 6 weeks of intravenous antibiotics with resolution of his symptoms.This case illustrates the importance of challenging a previous diagnosis, including repeat examination, when a patient's condition does not evolve as expected. Endocarditis is recognised as a great imitator and the diagnosis remains challenging.


Assuntos
Endocardite Bacteriana/diagnóstico , Infecções Estreptocócicas/diagnóstico , Streptococcus , Corticosteroides/uso terapêutico , Insuficiência da Valva Aórtica/diagnóstico , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/etiologia , Sudeste Asiático , Ecocardiografia Transesofagiana , Endocardite Bacteriana/complicações , Endocardite Bacteriana/diagnóstico por imagem , Endocardite Bacteriana/microbiologia , Arterite de Células Gigantes/diagnóstico , Arterite de Células Gigantes/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/microbiologia , Viagem , Falha de Tratamento
14.
Biol Lett ; 13(4)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28381631

RESUMO

Restricting future global temperature increase to 2°C or less requires the adoption of negative emissions technologies for carbon capture and storage. We review the potential for deployment of enhanced weathering (EW), via the application of crushed reactive silicate rocks (such as basalt), on over 680 million hectares of tropical agricultural and tree plantations to offset fossil fuel CO2 emissions. Warm tropical climates and productive crops will substantially enhance weathering rates, with potential co-benefits including decreased soil acidification and increased phosphorus supply promoting higher crop yields sparing forest for conservation, and reduced cultural eutrophication. Potential pitfalls include the impacts of mining operations on deforestation, producing the energy to crush and transport silicates and the erosion of silicates into rivers and coral reefs that increases inorganic turbidity, sedimentation and pH, with unknown impacts for biodiversity. We identify nine priority research areas for untapping the potential of EW in the tropics, including effectiveness of tropical agriculture at EW for major crops in relation to particle sizes and soil types, impacts on human health, and effects on farmland, adjacent forest and stream-water biodiversity.


Assuntos
Mudança Climática , Agricultura , Conservação dos Recursos Naturais , Florestas , Humanos , Clima Tropical , Tempo (Meteorologia)
15.
Eur J Cardiothorac Surg ; 48(4): 524-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25762394

RESUMO

The decision-making process in the management of patients with ischaemic heart disease has historically been the responsibility of the cardiologist and encompasses medical management, percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG). Currently, there is significant geographical variability in the PCI:CABG ratio. There are now emerging recommendations that this decision-making process should be carried out through a multidisciplinary approach, namely the Heart Team. This work was carried out on behalf of The British Cardiovascular Society (BCS), Society for Cardiothoracic Surgery in Great Britain and Ireland (SCTS) and British Cardiovascular Intervention Society (BCIS). This manuscript sets out the principles for the functioning of the Heart Team. This work has been approved by the Executive Committees of BCS/BCIS/SCTS.


Assuntos
Ponte de Artéria Coronária/normas , Doença da Artéria Coronariana/terapia , Equipe de Assistência ao Paciente/organização & administração , Intervenção Coronária Percutânea/normas , Guias de Prática Clínica como Assunto , Doença da Artéria Coronariana/diagnóstico , Tomada de Decisões , Feminino , Humanos , Comunicação Interdisciplinar , Irlanda , Masculino , Qualidade da Assistência à Saúde , Sociedades Médicas/normas , Reino Unido
16.
Nucl Med Commun ; 36(4): 386-91, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25569866

RESUMO

AIM: The aim of the study was to investigate whether myocardial perfusion imaging at 15 min after injection (T15) is more accurate in detecting coronary artery disease than that at 45 min (T45). PATIENTS AND METHODS: Two-day stress/rest 99mTc-tetrofosmin gated SPECT was performed at T15 and T45 in 50 patients. Coronary angiography was considered when poststress and resting images were discordant. Tracer washout rates were calculated for the myocardium, liver, and subdiaphragmatic region. Perfusion sum difference scores were derived using QPS software. RESULTS: T15 and T45 were discordant in 18/50 (36%) patients. In 16/18 patients (89%) discordant deficits were more apparent at T15. A total of 13/16 patients underwent coronary angiography, of whom 12 had coronary artery disease. Poststress, but not resting, left ventricular ejection fraction was lower at T15 (P=0.02). Sum difference scores were higher at T15 [2.2 (1.9)] than at T45 [1.6 (1.7); P<0.05]. Tracer washout rates from the liver [46 (13.3)%] and subdiaphragmatic region [36 (21.3)%] were significant (P<0.0001), but there was no change in myocardial activity. CONCLUSION: T15 detected more abnormalities than did T45. The reduction in left ventricular ejection fraction after stress may result from adenosine-induced poststunning at T15. Accordingly, the T15 protocol may be useful in the assessment of hibernating myocardium. Contrasting myocardial and hepatic washout rates may be attributable to differential ABC transporter expression.


Assuntos
Adenosina , Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Imagem de Perfusão do Miocárdio/métodos , Idoso , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados , Compostos de Organotecnécio , Volume Sistólico , Tecnécio Tc 99m Sestamibi , Fatores de Tempo , Disfunção Ventricular Esquerda/diagnóstico por imagem
17.
Eur Heart J Cardiovasc Imaging ; 15(7): 747-52, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24408932

RESUMO

AIMS: There are minimal data on methods to measure and improve quality in image interpretation when reporting cardiovascular imaging studies. We sought to identify the feasibility and clinical utility of a nationally implemented quality assurance (QA) process. METHODS AND RESULTS: A web-based platform was developed to administer a national QA module to 27 echocardiography departments within the UK. Three QA modules were delivered from 2011. The proportion of units using the QA module increased from 14 (52.2%) in the first module to 22 (81.5%) in the third module. There was no significant change in the proportion of correct answers between the first module (88.9%) and the third module (82.8%), P = 0.3. The number of echocardiographers with at least one incorrect answer increased from 16 (21.6%) in the first module to 54 (34%) in the third module, P = 0.03. Overall, in valvular heart disease cases there were 36 (10.6%) incorrect responses where qualitative assessment of the severity of valve dysfunction was tested compared with 4 (3.6%) incorrect responses where quantitative assessment of valve dysfunction was tested, P = 0.04. In chamber quantification cases, there were 36 (6.8%) incorrect responses where qualitative assessment of chamber function was tested compared with 3 (2.1%) incorrect responses where quantitative assessment of chamber function was tested, P = 0.04. CONCLUSION: The incorporation of national QA programme is feasible with rapid uptake. The platform allows comparison of an individual's interpretation skills against a reference standard which can be used as a method to identify inter-observer variability and as a training tool.


Assuntos
Ecocardiografia/métodos , Troca de Informação em Saúde , Disseminação de Informação , Internet , Melhoria de Qualidade/organização & administração , Serviço Hospitalar de Cardiologia/organização & administração , Bases de Dados Factuais , Estudos de Viabilidade , Humanos , Interpretação de Imagem Assistida por Computador , Variações Dependentes do Observador , Desenvolvimento de Programas , Padrões de Referência , Reino Unido
18.
Mar Environ Res ; 96: 29-37, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24080408

RESUMO

Bathymodiolin mussels are amongst the dominant fauna occupying hydrothermal vent ecosystems throughout the World's oceans. This subfamily inhabits a highly ephemeral and variable environment, where exceptionally high concentrations of reduced sulphur species and heavy metals necessitate adaptation of specialised detoxification mechanisms. Whilst cellular responses to common anthropogenic pollutants are well-studied in shallow-water species, they remain limited in deep-sea vent fauna. Bathymodiolus sp. were sampled from two newly-discovered vent sites on the Southwest Indian Ridge (Tiamat and Knuckers Gaff) by the remotely operated vehicle (ROV) Kiel 6000 during the RRS James Cook cruise, JC 067 in November 2011. Here, we use redox proteomics to investigate the effects of tissue metal accumulation on protein expression and thiol oxidation in gill. Following 2D PAGE, we demonstrate a significant difference in intensity in 30 protein spots in this organ between the two vent sites out of 205 matched spots. We also see significant variations in thiol oxidation in 15 spots, out of 143 matched. At Tiamat, 23 protein spots are up-regulated compared to Knuckers Gaff and we identify 5 of these with important roles in metabolism, cell structure, stress response, and redox homeostasis. We suggest that increased metal exposure triggers changes in the proteome, regulating tissue uptake. This is evident both between vent sites and across a chemical gradient within the Knuckers Gaff vent site. Our findings highlight the importance of proteomic plasticity in successful adaptation to the spatially and temporally fluctuating chemical environments that are characteristic of hydrothermal vent habitats.


Assuntos
Exposição Ambiental , Metais/toxicidade , Mytilidae/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Adaptação Fisiológica , Animais , Eletroforese em Gel de Poliacrilamida , Monitoramento Ambiental , Fontes Hidrotermais , Oceano Índico , Metais/farmacocinética , Mytilidae/genética , Mytilidae/metabolismo , Oxirredução , Proteoma/genética , Proteoma/metabolismo , Proteômica , Distribuição Tecidual , Poluentes Químicos da Água/farmacocinética
19.
J Invasive Cardiol ; 25(3): 142-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23468444

RESUMO

AIMS: Right ventricular dysfunction is a well recognized adverse prognostic factor in patients undergoing surgical aortic valve replacement. The prognostic significance of right ventricular dysfunction in the context of transcatheter aortic valve implantation (TAVI) has not been established. We evaluated the relationship between preprocedural right ventricular impairment and the outcome of TAVI. METHODS AND RESULTS: Between December 2007 and December 2011, a total of 155 patients with severe aortic stenosis underwent TAVI at the Sussex Cardiac Centre, of whom 83%-91% had prospective analysis of right ventricular function prior to TAVI using two different standard echocardiographic methods. We identified patients with preserved and impaired ventricular function and compared their all-cause mortality during follow-up. Right ventricular dysfunction was defined as tricuspid annular plane systolic excursion (TAPSE) <15 mm or right ventricular peak systolic velocity (RVPSV) <9 cm/s and was identified in 11% of patients. Vital status was established from the Office of National Statistics. Average follow-up was 628 ± 392 days. A total of 107 patients were followed for at least 1 year and 63 patients for at least 2 years. Cumulative total mortality was 17.4%. In-hospital mortality was 2.6%, death within 30 days was 5.8%, 1-year mortality was 14.0%, and 2-year mortality was 15.9%. There was no statistically significant difference in outcome between patients with and without right ventricular dysfunction. This finding was consistent between the two methods used to determine right ventricular function (TAPSE: hazard ratio [HR] 1.57 and P=.42; RVPSV: HR 1.28 and P=.71). CONCLUSIONS: Preprocedural right ventricular dysfunction does not adversely impair immediate or follow-up survival during medium-term follow-up after TAVI.


Assuntos
Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/terapia , Valva Aórtica , Cateterismo Cardíaco , Implante de Prótese de Valva Cardíaca , Disfunção Ventricular Direita/complicações , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/mortalidade , Feminino , Seguimentos , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Cobertura de Condição Pré-Existente , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
20.
Heart Lung Circ ; 22(9): 717-23, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23499523

RESUMO

BACKGROUND: We aimed to assess whether echocardiographically-optimised atrioventricular (AV) and interventricular (VV) delay programming provided any additional benefit over standard settings following biventricular pacemaker implantation in patients with advanced heart failure. METHODS: Paired data were collected on 22 patients (aged 67.5 ± 8.3 years, 16 male) with refractory heart failure, NYHA class III/IV symptoms, sinus rhythm, LBBB and a broad QRS complex >120 ms. All patients underwent implantation of a biventricular pacemaker and were randomised to eight weeks of factory pacing mode (Mode 1) or echocardiographically-guided pacing mode (Mode 2), followed by eight weeks in the alternate mode, in a randomised blinded crossover design. RESULTS: Peak oxygen consumption, 6 min walk distance, NYHA class and quality of life scores improved after biventricular pacing, but no significant difference was found between the two modes, with the exception of peak oxygen consumption score (baseline: 14.8 ± 0.9, Mode 1: 14.6 ± 1.2, Mode 2: 16.1 ± 1.2 mL/kg/min), which was better in Mode 2 than Mode 1 (p 0.003). CONCLUSION: Transthoracic echocardiographic optimisation of AV and VV delays following biventricular pacing may offer additional clinical benefit in an unselected group of patients when compared with factory settings.


Assuntos
Dispositivos de Terapia de Ressincronização Cardíaca , Terapia de Ressincronização Cardíaca/métodos , Insuficiência Cardíaca/cirurgia , Idoso , Estudos Cross-Over , Ecocardiografia/métodos , Feminino , Seguimentos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade
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