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1.
Nat Commun ; 11(1): 2731, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32518292

RESUMO

Identification of habitable planets beyond our solar system is a key goal of current and future space missions. Yet habitability depends not only on the stellar irradiance, but equally on constituent parts of the planetary atmosphere. Here we show, for the first time, that radiatively active mineral dust will have a significant impact on the habitability of Earth-like exoplanets. On tidally-locked planets, dust cools the day-side and warms the night-side, significantly widening the habitable zone. Independent of orbital configuration, we suggest that airborne dust can postpone planetary water loss at the inner edge of the habitable zone, through a feedback involving decreasing ocean coverage and increased dust loading. The inclusion of dust significantly obscures key biomarker gases (e.g. ozone, methane) in simulated transmission spectra, implying an important influence on the interpretation of observations. We demonstrate that future observational and theoretical studies of terrestrial exoplanets must consider the effect of dust.


Assuntos
Biomarcadores/análise , Poeira/análise , Exobiologia , Meio Ambiente Extraterreno , Minerais/análise , Planetas , Atmosfera , Clima , Simulação por Computador , Temperatura
2.
BJU Int ; 125(4): 561-567, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31955483

RESUMO

OBJECTIVES: To externally validate a nomogram recently proposed by Larcher et al. (BJU Int. 2017; 120: 490) and to develop a simplified model with comparable accuracy to guide on the need for staging chest computed tomography (CT) for patients with new renal masses. PATIENTS AND METHODS: We analysed the data of 1082 consecutive patients with unilateral enhancing renal masses referred to urology multidisciplinary team meetings at two centres between 2011 and 2017. All patients underwent a staging chest CT at diagnosis. We fitted multivariable logistic regression models and tested the Larcher model performance using area under the receiver-operating curve (AUC), calibration and decision curve analysis. RESULTS: Forty-two patients (3.9%) had a positive chest CT. The Larcher nomogram had an AUC of 83.8% (95% confidence interval [CI] 77.1-90.6), but was only moderately well calibrated (calibration-in-the-large = -0.61, slope = 0.82). Specifically, the nomogram overestimated the risk of positive chest CT, and the magnitude of miscalibration increased with increasing predicted risks. Using a stepwise backward approach, a new model was developed including tumour size, nodal stage and systemic symptoms. Compared with the Larcher model, the new model had a similar AUC (82.7% [95% CI 75.5-90.0]), but improved calibration and clinical net benefit. The predicted risk of positive chest CT was <1% in the low-risk group and 1.9-79.9% in the high-risk group. CONCLUSION: The Larcher nomogram is an accurate prediction tool that was moderately well calibrated with our dataset. However, our simplified model has similar accuracy and uses more objective variables available from referral, so may be easier to incorporate into clinical practice. The low-risk group from our model (tumour size ≤4 cm and no systemic symptoms) had a risk of positive chest CT <1%, suggesting these patients may forego chest CT.


Assuntos
Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Nomogramas , Medição de Risco/métodos , Tomografia Computadorizada por Raios X , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Tórax/diagnóstico por imagem
3.
Nat Commun ; 6: 7535, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-26102364

RESUMO

Any reduction in global mean near-surface temperature due to a future decline in solar activity is likely to be a small fraction of projected anthropogenic warming. However, variability in ultraviolet solar irradiance is linked to modulation of the Arctic and North Atlantic Oscillations, suggesting the potential for larger regional surface climate effects. Here, we explore possible impacts through two experiments designed to bracket uncertainty in ultraviolet irradiance in a scenario in which future solar activity decreases to Maunder Minimum-like conditions by 2050. Both experiments show regional structure in the wintertime response, resembling the North Atlantic Oscillation, with enhanced relative cooling over northern Eurasia and the eastern United States. For a high-end decline in solar ultraviolet irradiance, the impact on winter northern European surface temperatures over the late twenty-first century could be a significant fraction of the difference in climate change between plausible AR5 scenarios of greenhouse gas concentrations.

4.
Geophys Res Lett ; 42(13): 5485-5492, 2015 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-26937058

RESUMO

Radiation parameterizations in GCMs are more accurate than their predecessorsErrors in estimates of 4 ×CO2 forcing are large, especially for solar radiationErrors depend on atmospheric state, so global mean error is unknown.

5.
BJU Int ; 108(11): 1794-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21627751

RESUMO

UNLABELLED: What's known on the subject ? and What does the study add? The treatment of younger men with testicular germ cell cancers is well documented with established intensive chemotherapy regimens for those with advanced disease. Although the majority of patients present in the third or fourth decade, men also present in later life. These patients are typically excluded from clinical trials and there are no contemporary published series describing their management. This series describes the management of older patients with testicular germ cell tumours at both early and advanced stages of disease. Patients with stage I seminoma can be safely managed with all recognised treatment strategies and state I non-seminomas were managed with surveillance. Cure can still be achieved in older patients with advance germ cell tumours however chemotherapy regimens developed in younger patients must be tailored to the presence of co-morbidity. OBJECTIVES: • To review the practice of a large referral centre for the management of older patients with testicular germ cell cancer (GCC). • There are few published data available on the management of testicular GCC in elderly patients, who often have medical comorbidities and have been excluded from clinical trials. PATIENTS AND METHODS: • We reviewed our prospectively collected database for patients presenting with GCC who were aged ≥60 years. • Details of presentation, management and outcome were recorded. RESULTS: • In total, 60 patients aged ≥60 years were identified from 1461 patients treated with GCC from 1979-2005, representing 4% of the total population. • Median age was 67 years, 44 had seminoma (73%) and 16 had non-seminoma histology (27%). • Stage I seminoma patients were managed with surveillance, adjuvant radiotherapy and adjuvant carboplatin. All stage I non-seminomas underwent surveillance. • In total, 15 patients received systemic chemotherapy for metastatic disease with modified bleomycin, etoposide and cisplatin; etoposide and cisplatin; carboplatin-based regimens; or other combinations. Toxicity was manageable, with no toxic deaths. • In total, four patients (6.7%) died of GCC. CONCLUSIONS: • In elderly patients, GCC should be managed with curative intent. • Conventional therapies are tolerable for most men with stage I seminoma. In metastatic disease, comorbidity may necessitate treatment modifications. • Most patients are cured with manageable toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Embrionárias de Células Germinativas/terapia , Neoplasias Testiculares/terapia , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/secundário , Estudos Prospectivos , Radioterapia Adjuvante , Seminoma/patologia , Seminoma/secundário , Seminoma/terapia , Análise de Sobrevida , Neoplasias Testiculares/patologia , Resultado do Tratamento
6.
Nat Rev Urol ; 7(12): 694-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21045799

RESUMO

BACKGROUND: A 70-year-old man with a history of hypertension presented with severe epigastric discomfort that radiated to his back. CT revealed cystic kidney disease and a large retroperitoneal hemorrhage, and CT angiography identified an active bleeding point in the region of the left adrenal gland. Selective left renal angiography identified a small inferior adrenal artery aneurysm with active hemorrhage. The patient underwent successful transcatheter embolization with microcoils and polyvinyl alcohol microparticles to control the bleeding. INVESTIGATIONS: Blood tests, urinalysis, electrocardiography, triphasic CT with CT angiography. DIAGNOSIS: Ruptured left inferior adrenal artery aneurysm. MANAGEMENT: Access to the inferior adrenal artery was achieved with a microcatheter, followed by transcatheter embolization using a combination of polyvinyl alcohol microparticles distally and microcoils proximally to the aneurysm.


Assuntos
Glândulas Suprarrenais/irrigação sanguínea , Aneurisma Roto/terapia , Artérias , Embolização Terapêutica , Idoso , Humanos , Masculino , Radiografia Intervencionista
7.
Heart Lung Circ ; 17(1): 76-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17449322

RESUMO

A 55-year-old female developed dyspnoea following an elective hysteroscopy. A chest radiograph demonstrated a tissue density opacity occupying the right hemithorax. A CT scan suggested this was a tumour arising from the postero-lateral chest wall. Surgical resection was attempted; however, mobilisation of the tumour caused significant airway compromise. Cardiopulmonary bypass was used to facilitate oxygenation while the tumour was dissected and removed. Although cardiopulmonary bypass has been used as an adjunct to aid resection of tumours invading major vascular or upper airway structures, in this case CPB was used to aid mobilisation of a giant pleural tumour.


Assuntos
Ponte Cardiopulmonar/métodos , Fibroma/patologia , Fibroma/cirurgia , Neoplasias Pleurais/patologia , Neoplasias Pleurais/cirurgia , Terapia Combinada , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Feminino , Seguimentos , Humanos , Histeroscopia/efeitos adversos , Imuno-Histoquímica , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/cirurgia , Medição de Risco , Toracotomia/métodos , Resultado do Tratamento
8.
Interact Cardiovasc Thorac Surg ; 6(2): 247-50, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17669829

RESUMO

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed whether pyloroplasty following elective esophagectomy improves clinical outcomes. Altogether 170 relevant papers were identified using the below-mentioned search. One meta-analysis and six randomised controlled trials from the nine that were summarised in the meta-analysis represented the best evidence to answer the question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses were tabulated. We conclude that pyloroplasty seems to reduce the incidence of gastric outlet obstruction and speed up gastric emptying. In addition, the incidence of complications from this procedure seems low. However, other significant improvements to outcomes such as mortality, nutrition, anastomotic leakage, gastric symptoms and aspiration are yet to be established.


Assuntos
Adenocarcinoma/cirurgia , Drenagem , Neoplasias Esofágicas/cirurgia , Esofagectomia , Junção Esofagogástrica/cirurgia , Gastroplastia/métodos , Piloro/cirurgia , Adenocarcinoma/fisiopatologia , Drenagem/efeitos adversos , Neoplasias Esofágicas/fisiopatologia , Esofagectomia/efeitos adversos , Esvaziamento Gástrico , Obstrução da Saída Gástrica/epidemiologia , Obstrução da Saída Gástrica/etiologia , Gastroplastia/efeitos adversos , Humanos , Incidência , Resultado do Tratamento
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