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1.
Nature ; 618(7965): 480-483, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37198479

RESUMO

In the first billion years after the Big Bang, sources of ultraviolet (UV) photons are believed to have ionized intergalactic hydrogen, rendering the Universe transparent to UV radiation. Galaxies brighter than the characteristic luminosity L* (refs. 1,2) do not provide enough ionizing photons to drive this cosmic reionization. Fainter galaxies are thought to dominate the photon budget; however, they are surrounded by neutral gas that prevents the escape of the Lyman-α photons, which has been the dominant way to identify them so far. JD1 was previously identified as a triply-imaged galaxy with a magnification factor of 13 provided by the foreground cluster Abell 2744 (ref. 3), and a photometric redshift of z ≈ 10. Here we report the spectroscopic confirmation of this very low luminosity (≈0.05 L*) galaxy at z = 9.79, observed 480 Myr after the Big Bang, by means of the identification of the Lyman break and redward continuum, as well as multiple ≳4σ emission lines, with the Near-InfraRed Spectrograph (NIRSpec) and Near-InfraRed Camera (NIRCam) instruments. The combination of the James Webb Space Telescope (JWST) and gravitational lensing shows that this ultra-faint galaxy (MUV = -17.35)-with a luminosity typical of the sources responsible for cosmic reionization-has a compact (≈150 pc) and complex morphology, low stellar mass (107.19 M⊙) and subsolar (≈0.6 Z⊙) gas-phase metallicity.

2.
Radiol Bras ; 56(5): 242-247, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38204905

RESUMO

Objective: To assess inflammatory bowel disease (IBD) activity with Doppler ultrasound in pediatric patients, comparing the accuracy of the ultrasound findings with that of the concentrations of fecal calprotectin (FC). Materials and Methods: In a consecutive series, we evaluated 53 examinations of 44 pediatric patients seen between 2014 and 2020: 28 with Crohn's disease, 15 with ulcerative colitis, and one with IBD unclassified. The diagnosis of IBD was made in accordance with the Porto criteria. The alteration studied in the greatest detail was bowel wall flow, which was classified by the lead investigator and two pediatric radiologists, all of whom were blinded to the FC concentrations and the other ultrasound findings. Bowel wall flow was categorized as low if there were up to 2 Doppler ultrasound signals/cm2, moderate if there were 3-5 signals/cm2, and high if there were more than 5 signals/cm2. Results: The agreement among the radiologists was substantial (kappa = 0.73). In cases in which ultrasound showed low bowel wall flow, the median FC concentration was 92 µg/g (interquartile range, 33-661 µg/g), whereas it was 2,286 µg/g (interquartile range, 1,728-5,612 µg/g) in those in which ultrasound showed high bowel wall flow. In the sample as a whole, the sensitivity and specificity of ultrasound was 89.7% and 92.0%, respectively, for the detection of inflammatory activity; 95.5% and 90.9%, respectively, for the detection of Crohn's disease; and 81.3% and 100.0%, respectively, for the detection of ulcerative colitis. Conclusion: Ultrasound of the bowel wall showed a strong correlation with FC concentrations in the assessment of inflammatory activity in pediatric patients with IBD.


Objetivo: Avaliar a atividade da doença inflamatória intestinal (DII) por ultrassonografia (US) com Doppler em cores, comparada à concentração de calprotectina fecal (CF) em pacientes pediátricos. Materiais e Métodos: Em uma série consecutiva, no período entre 2014 e 2020, foram avaliados 53 exames de 44 pacientes pediátricos: 28 casos de doença de Crohn, 15 de colite ulcerativa e um de colite indeterminada. O diagnóstico da DII foi feito pelos critérios de Porto. O fluxo parietal foi a alteração estudada mais detalhadamente e classificada pelo pesquisador principal e por dois radiologistas pediátricos cegados aos valores de CF e de US Doppler. Baixo fluxo parietal foi definido pela captação de até 2 sinais de US Doppler/cm2, fluxo moderado entre 3 e 5 sinais/cm2 e alto fluxo mais de 5 sinais/cm2. Resultados: Houve concordância substancial entre os radiologistas (kappa = 0,73). Nos exames com baixo fluxo parietal a CF média foi 92 µg/g (intervalo interquartil: 33-661 µg/g) e nos exames com alto fluxo a CF média foi 2.286 µg/g (intervalo interquartil: 1.728-5.612 µg/g). Na amostra total, a US demonstrou sensibilidade de 89,7% e especificidade de 92,0% para detecção da atividade inflamatória, 95,5% e 90,9% na doença de Crohn e 81,3% e 100,0% na colite ulcerativa, respectivamente. Conclusão: Houve forte correlação entre a US da parede intestinal e os valores da concentração de CF na avaliação da atividade inflamatória na DII de pacientes pediátricos.

3.
Radiol. bras ; 56(5): 242-247, Sept.-Oct. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1529314

RESUMO

Abstract Objective: To assess inflammatory bowel disease (IBD) activity with Doppler ultrasound in pediatric patients, comparing the accuracy of the ultrasound findings with that of the concentrations of fecal calprotectin (FC). Materials and Methods: In a consecutive series, we evaluated 53 examinations of 44 pediatric patients seen between 2014 and 2020: 28 with Crohn's disease, 15 with ulcerative colitis, and one with IBD unclassified. The diagnosis of IBD was made in accordance with the Porto criteria. The alteration studied in the greatest detail was bowel wall flow, which was classified by the lead investigator and two pediatric radiologists, all of whom were blinded to the FC concentrations and the other ultrasound findings. Bowel wall flow was categorized as low if there were up to 2 Doppler ultrasound signals/cm2, moderate if there were 3-5 signals/cm2, and high if there were more than 5 signals/cm2. Results: The agreement among the radiologists was substantial (kappa = 0.73). In cases in which ultrasound showed low bowel wall flow, the median FC concentration was 92 µg/g (interquartile range, 33-661 µg/g), whereas it was 2,286 µg/g (interquartile range, 1,728-5,612 µg/g) in those in which ultrasound showed high bowel wall flow. In the sample as a whole, the sensitivity and specificity of ultrasound was 89.7% and 92.0%, respectively, for the detection of inflammatory activity; 95.5% and 90.9%, respectively, for the detection of Crohn's disease; and 81.3% and 100.0%, respectively, for the detection of ulcerative colitis. Conclusion: Ultrasound of the bowel wall showed a strong correlation with FC concentrations in the assessment of inflammatory activity in pediatric patients with IBD.


Resumo Objetivo: Avaliar a atividade da doença inflamatória intestinal (DII) por ultrassonografia (US) com Doppler em cores, comparada à concentração de calprotectina fecal (CF) em pacientes pediátricos. Materiais e Métodos: Em uma série consecutiva, no período entre 2014 e 2020, foram avaliados 53 exames de 44 pacientes pediátricos: 28 casos de doença de Crohn, 15 de colite ulcerativa e um de colite indeterminada. O diagnóstico da DII foi feito pelos critérios de Porto. O fluxo parietal foi a alteração estudada mais detalhadamente e classificada pelo pesquisador principal e por dois radiologistas pediátricos cegados aos valores de CF e de US Doppler. Baixo fluxo parietal foi definido pela captação de até 2 sinais de US Doppler/cm2, fluxo moderado entre 3 e 5 sinais/cm2 e alto fluxo mais de 5 sinais/cm2. Resultados: Houve concordância substancial entre os radiologistas (kappa = 0,73). Nos exames com baixo fluxo parietal a CF média foi 92 μg/g (intervalo interquartil: 33-661 μg/g) e nos exames com alto fluxo a CF média foi 2.286 μg/g (intervalo interquartil: 1.728-5.612 μg/g). Na amostra total, a US demonstrou sensibilidade de 89,7% e especificidade de 92,0% para detecção da atividade inflamatória, 95,5% e 90,9% na doença de Crohn e 81,3% e 100,0% na colite ulcerativa, respectivamente. Conclusão: Houve forte correlação entre a US da parede intestinal e os valores da concentração de CF na avaliação da atividade inflamatória na DII de pacientes pediátricos.

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