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1.
J Geophys Res Planets ; 127(6): e2022JE007189, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35865671

RESUMO

We present a reanalysis (using the Minnaert limb-darkening approximation) of visible/near-infrared (0.3-2.5 µm) observations of Uranus and Neptune made by several instruments. We find a common model of the vertical aerosol distribution i.e., consistent with the observed reflectivity spectra of both planets, consisting of: (a) a deep aerosol layer with a base pressure >5-7 bar, assumed to be composed of a mixture of H2S ice and photochemical haze; (b) a layer of photochemical haze/ice, coincident with a layer of high static stability at the methane condensation level at 1-2 bar; and (c) an extended layer of photochemical haze, likely mostly of the same composition as the 1-2-bar layer, extending from this level up through to the stratosphere, where the photochemical haze particles are thought to be produced. For Neptune, we find that we also need to add a thin layer of micron-sized methane ice particles at ∼0.2 bar to explain the enhanced reflection at longer methane-absorbing wavelengths. We suggest that methane condensing onto the haze particles at the base of the 1-2-bar aerosol layer forms ice/haze particles that grow very quickly to large size and immediately "snow out" (as predicted by Carlson et al. (1988), https://doi.org/10.1175/1520-0469(1988)045<2066:CMOTGP>2.0.CO;2), re-evaporating at deeper levels to release their core haze particles to act as condensation nuclei for H2S ice formation. In addition, we find that the spectral characteristics of "dark spots", such as the Voyager-2/ISS Great Dark Spot and the HST/WFC3 NDS-2018, are well modelled by a darkening or possibly clearing of the deep aerosol layer only.

2.
Ultrasound Obstet Gynecol ; 58(3): 469-475, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33533532

RESUMO

OBJECTIVE: To compare the diagnostic performance of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) in the prediction of deep myometrial invasion (DMI) and cervical stromal invasion (CSI) in patients with low-grade (Grade 1 or 2) endometrioid endometrial cancer (EEC). METHODS: This was a prospective study including all patients with low-grade EEC diagnosed between October 2013 and July 2018 at the Vall d'Hebron Hospital in Barcelona, Spain. Preoperative staging was performed using TVS and MRI, followed by surgical staging. Final histology was considered as the reference standard. Sensitivity, specificity, likelihood ratios and diagnostic accuracy were calculated for both imaging techniques in the prediction of DMI and CSI, and the agreement index was calculated for both techniques. The STARD 2015 guidelines were followed. RESULTS: A total of 131 patients with low-grade EEC were included consecutively. Sensitivity was higher for TVS than for MRI both for the prediction of DMI (69% (95% CI, 53-82%) vs 51% (95% CI, 36-66%), respectively) and CSI (43% (95% CI, 27-61%) vs 24% (95% CI, 12-41%), respectively). Specificity was similar for TVS and MRI in the prediction of DMI (87% (95% CI, 78-93%) vs 91% (95% CI, 82-96%)) and equal in the prediction of CSI (97% (95% CI, 91-99%) for both). The agreement index between TVS and MRI was 0.84 (95% CI, 0.76-0.90) for DMI and 0.92 (95% CI, 0.85-0.96) for CSI. CONCLUSIONS: The diagnostic performance of TVS is similar to that of MRI for the prediction of DMI and CSI in low-grade EEC, and TVS can play a role as a first-line imaging technique in the preoperative evaluation of low-grade EEC. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Carcinoma Endometrioide/diagnóstico por imagem , Neoplasias do Endométrio/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Invasividade Neoplásica/diagnóstico , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Endometrioide/patologia , Colo do Útero/diagnóstico por imagem , Neoplasias do Endométrio/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Miométrio/diagnóstico por imagem , Gradação de Tumores , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Período Pré-Operatório , Estudos Prospectivos , Sensibilidade e Especificidade , Espanha , Vagina/diagnóstico por imagem
3.
Nat Commun ; 11(1): 2281, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385300

RESUMO

In June 2015, Cassini high-resolution images of Saturn's limb southwards of the planet's hexagonal wave revealed a system of at least six stacked haze layers above the upper cloud deck. Here, we characterize those haze layers and discuss their nature. Vertical thickness of layers ranged from 7 to 18 km, and they extended in altitude ∼130 km, from pressure level 0.5 bar to 0.01 bar. Above them, a thin but extended aerosol layer reached altitude ∼340 km (0.4 mbar). Radiative transfer modeling of spectral reflectivity shows that haze properties are consistent with particles of diameter 0.07-1.4 µm and number density 100-500 cm-3. The nature of the hazes is compatible with their formation by condensation of hydrocarbon ices, including acetylene and benzene at higher altitudes. Their vertical distribution could be due to upward propagating gravity waves generated by dynamical forcing by the hexagon and its associated eastward jet.

4.
Clin Transl Oncol ; 22(8): 1272-1279, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31863354

RESUMO

PURPOSE: There is a gap in knowledge regarding the impact of micrometastases (MIC) and isolated tumor cells (ITCs) found in the sentinel lymph nodes of patients with endometrial cancer. Here, we present a meta-analysis of the published literature on the rate of MIC and ITCs after lymphatic mapping and determine trends in postoperative management. METHODS: Literature search of Medline and PubMed was done using the terms: micrometastases, isolated tumor cells, endometrial cancer, and sentinel lymph node. Inclusion criteria were: English-language manuscripts, retrospectives, or prospective studies published between January 1999 and June 2019. We removed manuscripts on sentinel node mapping that did not specify information on micrometastases or isolated tumor cells, non-English-language articles, no data about oncologic outcomes, and articles limited to ten cases or less. RESULTS: A total of 45 manuscripts were reviewed, and 8 studies met inclusion criteria. We found that the total number of patients with MIC/ITCs was 286 (187 and 99, respectively). The 72% of patients detected with MIC/ITCs in sentinel nodes received adjuvant therapies. The MIC/ITCs group has a higher relative risk of recurrence of 1.34 (1.07, 1.67) than the negative group, even if the adjuvant therapy was given. CONCLUSION: We noted that there is an increased relative risk of recurrence in patients with low-volume metastases, even after receiving adjuvant therapy. Whether adjuvant therapy is indicated remains a topic of debate because there are other uterine factors implicated in the prognosis. Multi-institutional tumor registries may help shed light on this important question.


Assuntos
Neoplasias do Endométrio/patologia , Micrometástase de Neoplasia/patologia , Recidiva Local de Neoplasia , Biópsia de Linfonodo Sentinela , Linfonodo Sentinela/patologia , Feminino , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela/estatística & dados numéricos
5.
Med. intensiva (Madr., Ed. impr.) ; 42(8): 463-472, nov. 2018. tab, graf
Artigo em Inglês | IBECS | ID: ibc-180518

RESUMO

OBJECTIVE: To assess whether patient age is independently associated to Intensive Care Unit (ICU) admission after non-cardiac surgery. DESIGN: An observational cohort study of the Spanish subset of the European Surgical Outcome Study (EuSOS) was carried out. SETTING: Hospitals of the public National Health Care System and private hospitals in Spain. Intervention: None. PATIENTS AND METHODS: All patients over 16 years of age undergoing inpatient non-cardiac surgery in the participating hospitals during a 7-day period in the month of April 2011 were consecutively included. Main variables of interest: ICU admission rate, factors associated with ICU admission and hospital mortality were assessed using logistic regression analysis and fractional polynomial regression. RESULTS: Out of 5412 patients, 677 (12.5%) were admitted to the ICU after surgery. The adjusted odds ratio (95% confidence interval [CI]) for ICU admission was 1.1 (0.8-1.4) for patients aged 65-74 years, 0.7 (0.5-1) for patients aged 75-85 years, and 0.4 (0.2-0.8) for patients over 85 years, respectively. Age, ASA score, grade of surgery (minor, intermediate, major), urgent surgery, surgical specialty, laparoscopic surgery and metastatic disease were independent factors for ICU admission. Global risk-adjusted mortality was 1.4 (95% CI 0.9-2.2). The ASA score, urgent surgery, surgical specialty and diabetes were predictors of hospital mortality. CONCLUSIONS: Elderly patients (over 80 years) appear less likely to be admitted to ICU after non-cardiac surgery in Spanish hospitals. There was no significant association between age and postoperative mortality in this cohort


OBJETIVO: Evaluar si la edad del paciente se asociaba independientemente con el ingreso en la unidad de cuidados intensivos (UCI) tras cirugía no cardiaca. DISEÑO: Estudio observacional de cohortes del subgrupo español del European Surgical Outcome Study (EuSOS). Ámbito: Hospitales públicos y privados en España. Intervención: Ninguna. PACIENTES Y MÉTODOS: Pacientes consecutivos mayores de 16 años sometidos a cirugía no cardiaca con ingreso durante un periodo de 7 días del mes de abril de 2011. Variables de interés principal: Tasa de ingreso en la UCI, factores asociados con ingreso en la UCI y mortalidad hospitalaria, analizadas mediante regresión logística y regresión fraccional polinómica. RESULTADOS: De 5.412 pacientes, 677 (12,5%) fueron ingresados en la UCI tras la cirugía. La odds ratio ajustada (intervalo de confianza [IC] del 95%) de ingreso en la UCI fue de 1,1 (0,8-1,4) para 65-74 años, 0,7 (0,5-1) para 75-85 años y de 0,4 (0,2-0,8) para más de 85 años, respectivamente. La edad, el grado ASA, el grado de la cirugía (menor, intermedia, mayor), la cirugía urgente, la especialidad quirúrgica, la cirugía laparoscópica y la enfermedad metastásica fueron factores independientes de ingreso en la UCI. El riesgo global ajustado de mortalidad fue de 1,4 (IC 95%: 0,9-2,2). El grado ASA, cirugía urgente, especialidad quirúrgica y diabetes fueron predictores de mortalidad hospitalaria. CONCLUSIONES: En los hospitales españoles, los pacientes ancianos (más de 80 años) son menos propensos a ser ingresados en la UCI tras cirugía no cardiaca. En esta cohorte, la edad y la mortalidad hospitalaria no se asociaron significativamente


Assuntos
Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Fatores Etários , Mortalidade Hospitalar , Unidades de Terapia Intensiva/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Arritmias Cardíacas/epidemiologia , Hospitais Privados/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Inquéritos e Questionários
6.
Nat Commun ; 9(1): 3709, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30213944

RESUMO

The radiant energy budget and internal heat are fundamental properties of giant planets, but precise determination of these properties remains a challenge. Here, we report measurements of Jupiter's radiant energy budget and internal heat based on Cassini multi-instrument observations. Our findings reveal that Jupiter's Bond albedo and internal heat, 0.503 ± 0.012 and 7.485 ± 0.160 W m-2 respectively, are significantly larger than 0.343 ± 0.032 and 5.444 ± 0.425 Wm-2, the previous best estimates. The new results help constrain and improve the current evolutionary theories and models for Jupiter. Furthermore, the significant wavelength dependency of Jupiter's albedo implies that the radiant energy budgets and internal heat of the other giant planets in our solar system should be re-examined. Finally, the data sets of Jupiter's characteristics of reflective solar spectral irradiance provide an observational basis for the models of giant exoplanets.

7.
Med Intensiva (Engl Ed) ; 42(8): 463-472, 2018 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29502889

RESUMO

OBJECTIVE: To assess whether patient age is independently associated to Intensive Care Unit (ICU) admission after non-cardiac surgery. DESIGN: An observational cohort study of the Spanish subset of the European Surgical Outcome Study (EuSOS) was carried out. SETTING: Hospitals of the public National Health Care System and private hospitals in Spain. INTERVENTION: None. PATIENTS AND METHODS: All patients over 16 years of age undergoing inpatient non-cardiac surgery in the participating hospitals during a 7-day period in the month of April 2011 were consecutively included. MAIN VARIABLES OF INTEREST: ICU admission rate, factors associated with ICU admission and hospital mortality were assessed using logistic regression analysis and fractional polynomial regression. RESULTS: Out of 5412 patients, 677 (12.5%) were admitted to the ICU after surgery. The adjusted odds ratio (95% confidence interval [CI]) for ICU admission was 1.1 (0.8-1.4) for patients aged 65-74 years, 0.7 (0.5-1) for patients aged 75-85 years, and 0.4 (0.2-0.8) for patients over 85 years, respectively. Age, ASA score, grade of surgery (minor, intermediate, major), urgent surgery, surgical specialty, laparoscopic surgery and metastatic disease were independent factors for ICU admission. Global risk-adjusted mortality was 1.4 (95% CI 0.9-2.2). The ASA score, urgent surgery, surgical specialty and diabetes were predictors of hospital mortality. CONCLUSIONS: Elderly patients (over 80 years) appear less likely to be admitted to ICU after non-cardiac surgery in Spanish hospitals. There was no significant association between age and postoperative mortality in this cohort.


Assuntos
Fatores Etários , Mortalidade Hospitalar , Unidades de Terapia Intensiva/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/epidemiologia , Grupos Diagnósticos Relacionados , Hospitais Privados/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Humanos , Tempo de Internação/estatística & dados numéricos , Pessoa de Meia-Idade , Espanha , Inquéritos e Questionários , Adulto Jovem
8.
HIV Med ; 18(1): 33-44, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27625009

RESUMO

OBJECTIVES: The aim of this work was to provide a reference for the CD4 T-cell count response in the early months after the initiation of combination antiretroviral therapy (cART) in HIV-1-infected patients. METHODS: All patients in the Collaboration of Observational HIV Epidemiological Research Europe (COHERE) cohort who were aged ≥ 18 years and started cART for the first time between 1 January 2005 and 1 January 2010 and who had at least one available measurement of CD4 count and a viral load ≤ 50 HIV-1 RNA copies/mL at 6 months (± 3 months) after cART initiation were included in the study. Unadjusted and adjusted references curves and predictions were obtained using quantile regressions. RESULTS: A total of 28 992 patients were included in the study. The median CD4 T-cell count at treatment initiation was 249 [interquartile range (IQR) 150, 336] cells/µL. The median observed CD4 counts at 6, 9 and 12 months were 382 (IQR 256, 515), 402 (IQR 274, 543) and 420 (IQR 293, 565) cells/µL. The two main factors explaining the variation of CD4 count at 6 months were AIDS stage and CD4 count at cART initiation. A CD4 count increase of ≥ 100 cells/mL is generally required in order that patients stay 'on track' (i.e. with a CD4 count at the same percentile as when they started), with slightly higher gains required for those starting with CD4 counts in the higher percentiles. Individual predictions adjusted for factors influencing CD4 count were more precise. CONCLUSIONS: Reference curves aid the evaluation of the immune response early after antiretroviral therapy initiation that leads to viral control.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Adolescente , Adulto , Idoso , Contagem de Linfócito CD4 , Estudos de Coortes , Monitoramento de Medicamentos , Europa (Continente) , Feminino , Infecções por HIV/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Viral , Adulto Jovem
9.
Ultrasound Obstet Gynecol ; 49(3): 379-386, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27214694

RESUMO

OBJECTIVES: To determine the longitudinal behavior of fetal biometric measures and cerebroplacental hemodynamics throughout gestation in fetuses with congenital heart disease (CHD). METHODS: Fetal biometry and Doppler hemodynamics (uterine artery (UtA), umbilical artery (UA) and fetal middle cerebral artery (MCA)) were measured serially in a cohort of consecutive fetuses diagnosed with CHD. Evaluations were made at various time points, from diagnosis (20-25 weeks) to delivery, with at least two measurements per fetus that were at least 2 weeks apart. Fetuses were classified into three groups according to the pattern of blood supply to the brain (placental vs systemic) that would be expected on the basis of the type of CHD. All parameters were transformed into Z-scores. A linear mixed model to analyze repeated measurements was constructed for each parameter to assess its behavior throughout gestation. RESULTS: Four hundred and forty-four ultrasound examinations were performed in 119 CHD fetuses, with a median of two measurements per fetus. The fetuses presented a small head at diagnosis (biparietal diameter (BPD) Z-score, -1.32 ± 0.99; head circumference (HC) Z-score, -0.79 ± 1.02), which remained small throughout gestation. UtA and UA pulsatility indices (PI) showed a significant increase towards the end of pregnancy, whereas no significant changes were observed in MCA-PI or cerebroplacental ratio (CPR) with gestational age. Both MCA and CPR presented significant differences in longitudinal behavior between CHD groups, while BPD and HC did not. CONCLUSIONS: CHD fetuses have a relatively small head from the second trimester of pregnancy, regardless of the type of CHD anomaly, and increasing resistance in the UtA and UA as pregnancy progresses, suggestive of increasing degree of placental impairment. Our findings indicate the early onset of mechanisms that could lead to poorer neurodevelopment later in life. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Biometria/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem , Artérias Umbilicais/diagnóstico por imagem , Artéria Uterina/diagnóstico por imagem , Feminino , Hemodinâmica , Humanos , Idade Materna , Artéria Cerebral Média/embriologia , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/embriologia , Artéria Uterina/embriologia , Adulto Jovem
10.
Nat Commun ; 7: 13262, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27824031

RESUMO

Saturn has an intense and broad eastward equatorial jet with a complex three-dimensional structure mixed with time variability. The equatorial region experiences strong seasonal insolation variations enhanced by ring shadowing, and three of the six known giant planetary-scale storms have developed in it. These factors make Saturn's equator a natural laboratory to test models of jets in giant planets. Here we report on a bright equatorial atmospheric feature imaged in 2015 that moved steadily at a high speed of 450 ms-1 not measured since 1980-1981 with other equatorial clouds moving within an ample range of velocities. Radiative transfer models show that these motions occur at three altitude levels within the upper haze and clouds. We find that the peak of the jet (latitudes 10° N to 10° S) suffers intense vertical shears reaching +2.5 ms-1 km-1, two orders of magnitude higher than meridional shears, and temporal variability above 1 bar altitude level.

11.
Ultrasound Obstet Gynecol ; 47(6): 680-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26823208

RESUMO

OBJECTIVES: To ascertain whether screening for pre-eclampsia (PE) and intrauterine growth restriction (IUGR) by uterine artery (UtA) Doppler in the second trimester of pregnancy and targeted surveillance improve maternal and perinatal outcomes in an unselected population. METHODS: This was a multicenter randomized open-label controlled trial. At the routine second-trimester anomaly scan, women were assigned randomly to UtA Doppler or non-Doppler groups. Women with abnormal UtA Doppler were offered intensive surveillance at high-risk clinics of the participating centers with visits every 4 weeks that included measurement of maternal blood pressure, dipstick proteinuria, fetal growth and Doppler examination. The primary outcome was a composite score for perinatal complications, defined as the presence of any of the following: PE, IUGR, spontaneous labor < 37 weeks' gestation, placental abruption, stillbirth, gestational hypertension, admission to neonatal intensive care unit and neonatal complications. Secondary outcomes were a composite score for maternal complications (disseminated intravascular coagulation, maternal mortality, postpartum hemorrhage, pulmonary edema, pulmonary embolism, sepsis), and medical interventions (for example, corticosteroid administration and induction of labor) in patients developing placenta-related complications. RESULTS: In total, 11 667 women were included in the study. Overall, PE occurred in 348 (3.0%) cases, early-onset PE in 48 (0.4%), IUGR in 722 (6.2%), early-onset IUGR in 93 (0.8%) and early-onset PE with IUGR in 32 (0.3%). UtA mean pulsatility index > 90(th) percentile was able to detect 59% of early-onset PE and 60% of early-onset IUGR with a false-positive rate of 11.1%. When perinatal and maternal data according to assigned group (UtA Doppler vs non-Doppler) were compared, no differences were found in perinatal or maternal complications. However, screened patients had more medical interventions, such as corticosteroid administration (relative risk (RR), 1.79 (95% CI, 1.4-2.3)) and induction of labor for IUGR (RR, 1.36 (95% CI, 1.07-1.72)). In women developing PE or IUGR, there was a trend towards fewer maternal complications (RR, 0.46 (95% CI, 0.19-1.11)). CONCLUSIONS: Routine second-trimester UtA Doppler ultrasound in an unselected population identifies approximately 60% of women at risk for placental complications; however, application of this screening test failed to improve short-term maternal and neonatal morbidity and mortality. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Retardo do Crescimento Fetal/diagnóstico por imagem , Pré-Eclâmpsia/diagnóstico por imagem , Resultado da Gravidez/epidemiologia , Ultrassonografia Doppler/métodos , Artéria Uterina/diagnóstico por imagem , Adulto , Feminino , Retardo do Crescimento Fetal/epidemiologia , Humanos , Pré-Eclâmpsia/epidemiologia , Gravidez , Segundo Trimestre da Gravidez , Fatores de Risco , Artéria Uterina/fisiologia , Resistência Vascular
13.
Nature ; 518(7540): 525-8, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25686601

RESUMO

The Martian limb (that is, the observed 'edge' of the planet) represents a unique window into the complex atmospheric phenomena occurring there. Clouds of ice crystals (CO2 ice or H2O ice) have been observed numerous times by spacecraft and ground-based telescopes, showing that clouds are typically layered and always confined below an altitude of 100 kilometres; suspended dust has also been detected at altitudes up to 60 kilometres during major dust storms. Highly concentrated and localized patches of auroral emission controlled by magnetic field anomalies in the crust have been observed at an altitude of 130 kilometres. Here we report the occurrence in March and April 2012 of two bright, extremely high-altitude plumes at the Martian terminator (the day-night boundary) at 200 to 250 kilometres or more above the surface, and thus well into the ionosphere and the exosphere. They were spotted at a longitude of about 195° west, a latitude of about -45° (at Terra Cimmeria), extended about 500 to 1,000 kilometres in both the north-south and east-west directions, and lasted for about 10 days. The features exhibited day-to-day variability, and were seen at the morning terminator but not at the evening limb, which indicates rapid evolution in less than 10 hours and a cyclic behaviour. We used photometric measurements to explore two possible scenarios and investigate their nature. For particles reflecting solar radiation, clouds of CO2-ice or H2O-ice particles with an effective radius of 0.1 micrometres are favoured over dust. Alternatively, the plume could arise from auroral emission, of a brightness more than 1,000 times that of the Earth's aurora, over a region with a strong magnetic anomaly where aurorae have previously been detected. Importantly, both explanations defy our current understanding of Mars' upper atmosphere.

14.
HIV Med ; 16(4): 211-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25234826

RESUMO

OBJECTIVES: The aim of the study was to investigate liver fibrosis outcome and the risk factors associated with liver fibrosis progression in hepatitis C virus (HCV)/HIV-coinfected patients. METHODS: We prospectively obtained liver stiffness measurements by transient elastography in a cohort of 154 HCV/HIV-coinfected patients, mostly Caucasian men on suppressive antiretroviral treatment, with the aim of determining the risk for liver stiffness measurement (LSM) increase and to identify the predictive factors for liver fibrosis progression. To evaluate LSM trends over time, a linear mixed regression model with LSM level as the outcome and duration of follow-up in years as the main covariate was fitted. RESULTS: After a median follow-up time of 40 months, the median increase in LSM was 1.05 kPa/year [95% confidence interval (CI) 0.72-1.38 kPa/year]. Fibrosis stage progression was seen in 47% of patients, and 17% progressed to cirrhosis. Aspartate aminotransferase (AST) levels and liver fibrosis stage at baseline were identified as independent predictors of LSM change. Patients with F3 (LSM 9.6-14.5 kPa) or AST levels ≥ 64 IU/L at baseline were at higher risk for accelerated LSM increase (ranging from 1.45 to 2.61 kPa/year), whereas LSM change was very slow among patients with both F0-F1 (LSM ≤ 7.5 kPa) and AST levels ≤ 64 IU/L at baseline (0.34 to 0.58 kPa/year). An intermediate risk for LSM increase (from 0.78 to 1.03 kPa/year) was seen in patients with F2 (LSM 7.6-9.5 kPa) and AST baseline levels ≤ 64 IU/L. CONCLUSIONS: AST levels and liver stiffness at baseline allow stratification of the risk for fibrosis progression and might be clinically useful to guide HCV treatment decisions in HIV-infected patients.


Assuntos
Aspartato Aminotransferases/metabolismo , Técnicas de Imagem por Elasticidade/métodos , Infecções por HIV/complicações , Hepatite C/complicações , Cirrose Hepática/induzido quimicamente , Fígado/patologia , Adulto , Fármacos Anti-HIV/efeitos adversos , Coinfecção/complicações , Progressão da Doença , Feminino , Seguimentos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Inibidores da Protease de HIV/efeitos adversos , Hepatite C/tratamento farmacológico , Hepatite C/patologia , Humanos , Fígado/metabolismo , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Espanha/epidemiologia
15.
Eur J Surg Oncol ; 39(7): 766-73, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23607911

RESUMO

INTRODUCTION: The one-step nucleic acid amplification (OSNA) is a molecular procedure that yields a semiquantitative result for detection of nodal metastasis. Size of metastasis in the sentinel lymph node (SLN) by conventional histology has been described as a predictive factor for additional axillary metastasis. The objective of this study is to quantify intraoperatively the total tumoral load (TTL) in the positive SLNs assessed by OSNA and to determine whether this TTL predicts non-SLN metastasis in patients with clinically node negative early stage breast cancer. METHODS: 306 patients with cT1-3N0 invasive breast cancer who had undergone intraoperative SLN evaluation by OSNA were included. TTL was defined as the addition of CK19 mRNA copies of each positive SLN (copies/µL). RESULTS: TTL was a predictive factor of additional non-SLN metastasis in the complete axillary lymph node dissection (cALND) (OR, 1.67; 95% CI, 1.18-2.35). In the multivariate analysis, the TTL was a predictor of non-SLN metastasis in HR positive patients (OR, 1.69; 95% CI, 1.19-2.41). In our cohort of patients, with a TTL ≤1.2 × 10(5) copies/µL, there was a specificity of 85.3% and negative predictive value (NPV) of 80%. If we consider only the HR positive patients, with a TTL ≤5 × 10(5) copies/µL there was a specificity of 86.7% and NPV of 83.7%. CONCLUSIONS: TTL assessed by OSNA assay predicts for additional non-SLN metastasis and this intraoperative tool can help guiding decisions on performing a cALND in breast cancer patients.


Assuntos
Neoplasias da Mama/patologia , Linfonodos/patologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Biópsia de Linfonodo Sentinela/métodos , Carga Tumoral , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Estudos de Coortes , Intervalos de Confiança , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Excisão de Linfonodo/métodos , Linfonodos/cirurgia , Metástase Linfática , Mastectomia/métodos , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , RNA Mensageiro/análise , Medição de Risco , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Análise de Sobrevida
16.
HIV Med ; 12(8): 500-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21794055

RESUMO

INTRODUCTION: The collection of incidence data on HIV infection is necessary to evaluate the status and dynamics of the epidemic and the effectiveness of intervention strategies. However, this is usually difficult in low-income countries. METHODS: Five yearly point HIV prevalence estimations (in 1999, 2003, 2004, 2005 and 2008) were obtained for women between 15 and 45 years of age participating in three studies carried out for other purposes at the Antenatal Clinic (ANC) in Manhiça, Mozambique. HIV incidence was estimated between prevalence points using a previously validated methodology. Two methods were used, one based on mortality rates for three HIV epidemic scenarios, and the other based on survival information after infection. The pattern over time was captured by fitting a log-regression model. RESULTS: The prevalence of HIV infection ranged from 12% in 1999 to 49% in 2008. The HIV incidence increased from approximately 3.5 cases per 100 person-years in 2001 to 14 per 100 person-years in 2004, with stabilization thereafter to levels of around 12 cases per 100 person-years. The incidence estimates were comparable for the two methods used. CONCLUSION: These findings indicate an increase in the prevalence and incidence of HIV infection among women of reproductive age over the 9 years of the analysis, with a plateau in the incidence of infection since 2005. However, the very high figures for both prevalence and incidence highlight the importance of the continuation of the prevention and treatment programmes that already exist, and suggest that implementation of preventive measures is needed in this area.


Assuntos
Infecções por HIV/epidemiologia , Adolescente , Adulto , Países em Desenvolvimento/estatística & dados numéricos , Feminino , Humanos , Incidência , Modelos Logísticos , Pessoa de Meia-Idade , Moçambique/epidemiologia , Gravidez , Prevalência , População Rural , Adulto Jovem
17.
Ultrasound Obstet Gynecol ; 38(2): 205-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21305638

RESUMO

OBJECTIVES: The aims of this study were to describe and assess the feasibility of measuring cervical length by standard transvaginal sonography (TVS) and transperineal sonography (TPS) in women with a cervical pessary and compare these measurements with those obtained with a new transvaginal technique. METHODS: Measurement of cervical length by TPS was attempted immediately before measurement using TVS in 48 women with a cervical pessary at between 22 and 23 weeks' gestation. The TVS procedure consisted of two types of measurement: in the first, the probe was placed on the anterior fornix (standard technique) and in the second, the probe was inserted into the pessary to touch the anterior cervical lip (new technique). Two physicians consecutively performed these procedures and compared the measurements obtained. Intraclass correlation coefficients (ICCs) with 95% CI were used to evaluate interobserver reliability, and Bland-Altman analysis was used to assess interobserver agreement. RESULTS: In total, 258 measurements (obtained from 43 women) were analyzed. Interobserver ICCs of the measurements obtained were 0.58 (95% CI, 0.34-0.75) for TPS, 0.65 (95% CI, 0.44-0.79) for the standard TVS technique and 0.97 (95% CI, 0.95-0.98) for the new TVS technique. Bland-Altman analysis showed small mean differences between measurements obtained by two physicians for the three methods, but with narrower limits of agreements (LOA) for the new TVS technique: TPS mean difference - 0.99 mm (95% LOA, - 13.23 to 11.25 mm), standard TVS technique mean difference - 0.23 mm (95% LOA, - 10.90 to 10.44 mm) and new TVS technique mean difference - 0.01 mm (95% LOA, - 2.57 to 2.55 mm). It was apparent from the images obtained that the external os was not visible in 89% of cases when either the TPS or standard TVS technique was used. However, the external os was visible in all cases when the new TVS method was used. CONCLUSIONS: We propose a new technique for measuring and monitoring cervical length in women with a cervical pessary that provides improved visualization of the cervix and increased reliability in comparison to established techniques.


Assuntos
Medida do Comprimento Cervical/métodos , Colo do Útero/diagnóstico por imagem , Pessários , Ultrassonografia Pré-Natal/métodos , Vagina/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Idade Gestacional , Humanos , Valor Preditivo dos Testes , Gravidez , Segundo Trimestre da Gravidez , Nascimento Prematuro , Reprodutibilidade dos Testes
18.
Enferm. clín. (Ed. impr.) ; 18(6): 317-320, nov. 2008. ilus
Artigo em Es | IBECS | ID: ibc-71325

RESUMO

Objetivo. Identificar los momentos críticos de la lactancia materna (LM) completa (LMC) y de abandono total de la LM a lo largo de un seguimiento de 6 meses. Método. Estudio descriptivo longitudinal, seguimiento de 6 meses de una muestra accidental de 270 madres con lactantes amamantados sanos. Análisis de supervivencia, cálculo de la densidad de incidencia (DI) de abandono de la LMC y LM por quincenas. Resultados. Pérdida de muestra 10% (4 meses) y 17% (6 meses). Mediana LMC de 120 días (intervalo de confianza [IC] del 95%, 111,17-128,83) y LM de 171 días (IC del 95%, 151,40 a > 180). La mediana de duración de la LM parcial (LMP) fue de 30 días (IC del 95%, 19,49-40,51). Picos de DI de LMC en la primera y segunda semanas y a partir de la semana 17. Los aumentos de DI de LM coinciden con los picos de la LMC e incluyen también las semanas posteriores. Conclusiones. El alta hospitalaria y el final de la prestación por maternidad son los momentos de mayor DI de abandono para la muestra estudiada. El abandono de la LMC y el de la LM están relacionados. Estos resultados sugieren la necesidad de aumentar el apoyo tras el alta, especialmente a las madres que ofrecen LMP y al reiniciar el trabajo


Objective. To identify critical moments for discontinuing full breast feeding (FBF) and any breast feeding (BF) in the first 6 months. Method. We performed an observational, 6-month follow-up study of an accidental sample of 270 mothers with healthy breastfed infants. Survival analyses and the incidence rates (IR) of discontinuance of FBF and ABF every fortnight were obtained. Results. Loss to follow-up: 10% at 4 months and 17% at 6 months. The median length of FBF was 120 days (95%CI = 111.17-128.83) and the median length of BF was 171 days (95% CI =151.40-190.60). The median duration of partial breast feeding (PBF) was 30 days (95% CI=19.49-40.51). IR peaks of BF were found in the first and second weeks and after week 17. Increases of the IR of BF coincided with IR peaks of FBF and also included subsequent weeks. Conclusions. The highest IR for discontinuance of BF were found at hospital discharge and return to work. PBF was related to weaning. These results suggest the need to increase support after discharge, especially to mothers PBF and those returning to work


Assuntos
Humanos , Feminino , Aleitamento Materno/estatística & dados numéricos , Comportamento de Sucção , Alimentação com Mamadeira , Epidemiologia Descritiva
19.
Eur J Epidemiol ; 23(6): 435-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18404406

RESUMO

To measure trends in HIV incidence and serial prevalence by sex in a intravenous drug users (IDUs) and heterosexuals (HT) cohort recruited in a counselling centre in Valencia (1988-2005). Serial prevalence and incidence rates were calculated and modelled by logistic and Poisson regression respectively. 5948 IDUs and 13343 HT were recruited. Prevalence was higher among female IDUs (46% vs. 41%), and female HT (4.1% vs. 2%). For IDUs, an interaction (P = 0.005) between sex and calendar was detected. Age-adjusted prevalence showed faster yearly decline in men (OR = 0.87 95%CI: 0.85-0.88) than in women (OR = 0.91 95%CI: 0.88-0.93). Incidence was higher in female IDUs (9.79% p-y) than in men, (5.38% p-y) with an annual decrease for both of 11%. HIV incidence was higher in female HT (0.62% p-y) compared to men 0.23% p-y with a 21% yearly decline. Gender differences in HIV prevalence and incidence trends have been detected. Women showed an increased vulnerability to infection in a country whose HIV epidemic has been largely driven by IDUs.


Assuntos
Soropositividade para HIV/epidemiologia , Abuso de Substâncias por Via Intravenosa/epidemiologia , Sorodiagnóstico da AIDS , Adolescente , Adulto , Feminino , Heterossexualidade , Humanos , Incidência , Modelos Logísticos , Masculino , Prevalência , Fatores Sexuais , Espanha/epidemiologia
20.
Nature ; 451(7177): 437-40, 2008 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-18216848

RESUMO

The atmospheres of the gas giant planets (Jupiter and Saturn) contain jets that dominate the circulation at visible levels. The power source for these jets (solar radiation, internal heat, or both) and their vertical structure below the upper cloud are major open questions in the atmospheric circulation and meteorology of giant planets. Several observations and in situ measurements found intense winds at a depth of 24 bar, and have been interpreted as supporting an internal heat source. This issue remains controversial, in part because of effects from the local meteorology. Here we report observations and modelling of two plumes in Jupiter's atmosphere that erupted at the same latitude as the strongest jet (23 degrees N). The plumes reached a height of 30 km above the surrounding clouds, moved faster than any other feature (169 m s(-1)), and left in their wake a turbulent planetary-scale disturbance containing red aerosols. On the basis of dynamical modelling, we conclude that the data are consistent only with a wind that extends well below the level where solar radiation is deposited.

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