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1.
Aquat Toxicol ; 261: 106623, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37429095

RESUMO

Implementation of the European Water Framework Directive in tropical areas such as the French West Indies (FWI) requires to select relevant aquatic sentinel species for investigating the ecological status of surface waters. The present work aimed to study the biological response of the widespread fish Sicydium spp. towards river chemical quality in Guadeloupe island through a set of proper biomarkers. During a 2-year survey, the hepatic EROD activity, the micronucleus formation and the level of primary DNA strand breaks in erythrocytes were measured respectively as an enzymatic biomarker of exposure and genotoxicity endpoints in fish living upstream and downstream of two chemically-contrasted rivers. Hepatic EROD activity was shown to be variable along the time but always significantly higher in fish from the most contaminated river (Rivière aux Herbes) compared to the low contaminated one (Grande Rivière de Vieux-Habitants). Fish size did not influence EROD activity. Female fish exhibited a lower EROD activity compared to males depending on the catching period. We observed significant temporal variation in micronucleus frequency and primary DNA damage level measured in fish erythrocytes that did not depend on the fish size. Micronucleus frequency and to a lesser extent DNA damage were significantly higher in fish from the Rivière aux Herbes compared to the Grande Rivière de Vieux-Habitants. Our results argue for the interest of using Sicydium spp. as sentinel species to assess river quality and chemical pressures in FWI.


Assuntos
Perciformes , Poluentes Químicos da Água , Animais , Masculino , Feminino , Poluentes Químicos da Água/toxicidade , Espécies Sentinelas , Monitoramento Ambiental/métodos , Citocromo P-450 CYP1A1 , Peixes , Rios , Biomarcadores , Índias Ocidentais
2.
Orbit ; 42(3): 336-342, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34913824

RESUMO

We present the case of a man in his fifties with a history of bladder carcinoma who presented with a large periorbital cystic lesion that was found to be a metastasis. Bladder carcinomas are a very rare cause of peri-/orbital metastasis. The primary tumor in this case predominately showed squamous cell differentiation and small areas of adenoid differentiation. To our knowledge only one previous case of orbital metastasis from squamous cell carcinoma of the bladder has been reported. Cyst formation in bladder cancer metastasis has not been reported and is very rare for orbital metastases in general. The pathogenesis of metastatic cyst development is not fully understood and may vary from case to case. A biopsy of an atypical cyst is indicated.


Assuntos
Carcinoma de Células Escamosas , Cistos , Neoplasias Orbitárias , Neoplasias da Bexiga Urinária , Masculino , Humanos , Bexiga Urinária/patologia , Neoplasias Orbitárias/diagnóstico por imagem , Neoplasias Orbitárias/secundário , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/secundário , Neoplasias da Bexiga Urinária/terapia
3.
Nat Commun ; 11(1): 4444, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895392

RESUMO

Energy-efficient control of magnetization without the help of a magnetic field is a key goal of spintronics. Purely heat-induced single-pulse all-optical toggle switching has been demonstrated, but so far only in Gd-based amorphous ferrimagnet films. In this work, we demonstrate toggle switching in films of the half-metallic ferrimagnetic Heusler alloys Mn2RuxGa, which have two crystallographically-inequivalent Mn sublattices. Moreover, we observe the switching at room temperature in samples that are immune to external magnetic fields in excess of 1 T, provided they exhibit a compensation point above room temperature. Observation of the effect in compensated ferrimagnets without Gd challenges our understanding of all-optical switching. The dynamic behavior indicates that Mn2RuxGa switches in 2 ps or less. Our findings widen the basis for fast optical switching of magnetization and break new ground for engineered materials that can be used for nonvolatile ultrafast switches using ultrashort pulses of light.

4.
AJNR Am J Neuroradiol ; 40(1): 25-32, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30573461

RESUMO

BACKGROUND AND PURPOSE: The rupture of an intracranial aneurysm is a serious incident, causing subarachnoid hemorrhage associated with high fatality and morbidity rates. Because the demand for radiologic examinations is steadily growing, physician fatigue due to an increased workload is a real concern and may lead to mistaken diagnoses of potentially relevant findings. Our aim was to develop a sufficient system for automated detection of intracranial aneurysms. MATERIALS AND METHODS: In a retrospective study, we established a system for the detection of intracranial aneurysms from 3D TOF-MRA data. The system is based on an open-source neural network, originally developed for segmentation of anatomic structures in medical images. Eighty-five datasets of patients with a total of 115 intracranial aneurysms were used to train the system and evaluate its performance. Manual annotation of aneurysms based on radiologic reports and critical revision of image data served as the reference standard. Sensitivity, false-positives per case, and positive predictive value were determined for different pipelines with modified pre- and postprocessing. RESULTS: The highest overall sensitivity of our system for the detection of intracranial aneurysms was 90% with a sensitivity of 96% for aneurysms with a diameter of 3-7 mm and 100% for aneurysms of >7 mm. The best location-dependent performance was in the posterior circulation. Pre- and postprocessing sufficiently reduced the number of false-positives. CONCLUSIONS: Our system, based on a deep learning convolutional network, can detect intracranial aneurysms with a high sensitivity from 3D TOF-MRA data.


Assuntos
Aprendizado Profundo , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Sci Rep ; 8(1): 9147, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29904111

RESUMO

Research in functional magnetic materials often employs thin films as model systems for finding new chemical compositions with promising properties. However, the scale-up of thin films towards bulk-like structures is challenging, since the material synthesis conditions are entirely different for thin films and e.g. rapid quenching methods. As one of the consequences, the type and degree of order in thin films and melt-spun ribbons are usually different, leading to different magnetic properties. In this work, using the example of magnetocaloric Ni-Co-Mn-Al melt-spun ribbons and thin films, we show that the excellent functional properties of the films can be reproduced also in ribbons, if an appropriate heat treatment is applied, that installs the right degree of order in the ribbons. We show that some chemical disorder is needed to get a pronounced and sharp martensitic transition. Increasing the order with annealing improves the magnetic properties only up to a point where selected types of disorder survive, which in turn compromise the magnetic properties. These findings allow us to understand the impact of the type and degree of disorder on the functional properties, paving the way for a faster transfer of combinatorial thin film research towards bulk-like materials for magnetic Heusler alloys.

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