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1.
J Int Med Res ; 52(4): 3000605241233141, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38629479

RESUMO

Rosai-Dorfman disease (RDD) is a rare non-Langerhans cell histiocytosis characterized by massive lymphadenopathy and systemic extranodal lesions. We present the case of a 28-year-old woman who presented with recurrent blurred vision in her right eye for 3 months. She developed blindness and atrophy in her left eye a decade prior to presentation. She subsequently developed headache, fever, and impaired mental status. Cranial magnetic resonance imaging indicated hypertrophic pachymeningitis (HP), and 18F-fluoro-2-deoxy-2-d-glucose (FDG) positron emission tomography/computed tomography revealed significant FDG uptake in the left dura mater. Autoimmune testing revealed elevated anti-nuclear, anti-SS-A, and anti-SS-B antibody levels. Incisional biopsy of the atrophic eyeball revealed RDD with marked polyclonal plasmacytosis. The patient was diagnosed with RDD accompanied by multisystem involvement, including Sjögren's syndrome (SS), panuveitis, and HP. Treatment with methylprednisolone for several weeks resulted in significant improvement. This is the first reported case of RDD presenting with SS in combination with panuveitis and HP. Although RDD is rarely diagnosed in young patients, interdisciplinary collaboration is essential to prevent a delayed diagnosis.


Assuntos
Histiocitose Sinusal , Pan-Uveíte , Síndrome de Sjogren , Humanos , Feminino , Adulto , Histiocitose Sinusal/complicações , Histiocitose Sinusal/diagnóstico , Histiocitose Sinusal/patologia , Síndrome de Sjogren/complicações , Síndrome de Sjogren/diagnóstico , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Hipertrofia , Pan-Uveíte/complicações , Pan-Uveíte/diagnóstico , Pan-Uveíte/tratamento farmacológico
2.
Nat Mater ; 23(3): 356-362, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38388731

RESUMO

The identification and characterization of spontaneous symmetry breaking is central to our understanding of strongly correlated two-dimensional materials. In this work, we utilize the angle-resolved measurements of transport non-reciprocity to investigate spontaneous symmetry breaking in twisted trilayer graphene. By analysing the angular dependence of non-reciprocity in both longitudinal and transverse channels, we are able to identify the symmetry axis associated with the underlying electronic order. We report that a hysteretic rotation in the mirror axis can be induced by thermal cycles and a large current bias, supporting the spontaneous breaking of rotational symmetry. Moreover, the onset of non-reciprocity with decreasing temperature coincides with the emergence of orbital ferromagnetism. Combined with the angular dependence of the superconducting diode effect, our findings uncover a direct link between rotational and time-reversal symmetry breaking. These symmetry requirements point towards exchange-driven instabilities in momentum space as a possible origin for transport non-reciprocity in twisted trilayer graphene.

3.
Int Immunopharmacol ; 124(Pt B): 110952, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37751655

RESUMO

PURPOSE: The abnormal polarisation of microglial cells (MGs) following retinal ischemia/reperfusion (RIR) initiates neuroinflammation and progressive death of retinal ganglion cells (RGCs), causing increasingly severe and irreversible visual dysfunction. Roflumilast (Roflu) is a promising candidate for treating neuroinflammatory diseases. This study aimed to explore whether Roflu displayed a cytoprotective effect against RIR-induced neuroinflammation and to characterise the underlying signalling pathway. METHODS: The effects and mechanism of Roflu against RIR injury were investigated in C57BL/6J mice and the BV2 cell line. We used quantitative real-time PCR and enzyme-linked immunosorbent assay to examine the levels of inflammatory factors. Furthermore, haematoxylin and eosin and immunofluorescence (IF) stainings were used to assess the morphology of the retina and the states of MGs and RGCs. Reactive oxygen species (ROS) levels were examined using a ROS assay kit, while whole-genome sequencing analysis was conducted to identify altered pathways and molecules. Western blotting and IF staining were used to quantify the proteins associated with the nuclear factor erythroid 2-related factor 2 (Nrf2)/stimulator of interferon gene (STING)/nuclear factor kappa beta (NF-κB) pathway. RESULTS: MG polarisation includes the pro-inflammatory and neurotoxic M1 phenotype as well as the anti-inflammatory and neuroprotective M2 phenotype. Roflu significantly attenuated MG activation and contributed to a shift in the MG phenotype from M1 to M2. Moreover, Roflu decreased ROS release and increased heme oxygenase 1 and NAD(P)H quinone oxidoreductase 1 expression. In vitro and in vivo experiments validated that Roflu exerted its neuroprotective effects primarily by upregulating the Nrf2/STING/NF-κB pathway. However, these effects were abrogated when the Nrf2 expression was inhibited by pharmacological or genetic manipulation. CONCLUSIONS: Roflu suppressed RIR-induced neuroinflammation by driving the shift of MG polarisation from M1 to M2 phenotype, which was mediated by the upregulation of the Nrf2/STING/NK-κB pathway.


Assuntos
NF-kappa B , Traumatismo por Reperfusão , Camundongos , Animais , NF-kappa B/metabolismo , Doenças Neuroinflamatórias , Fator 2 Relacionado a NF-E2/metabolismo , Microglia , Espécies Reativas de Oxigênio/metabolismo , Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Fenótipo , Retina/metabolismo , Traumatismo por Reperfusão/metabolismo , Isquemia/metabolismo
5.
Biomed Eng Online ; 19(1): 37, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32466753

RESUMO

Vessel diseases are often accompanied by abnormalities related to vascular shape and size. Therefore, a clear visualization of vasculature is of high clinical significance. Ultrasound color flow imaging (CFI) is one of the prominent techniques for flow visualization. However, clutter signals originating from slow-moving tissue are one of the main obstacles to obtain a clear view of the vascular network. Enhancement of the vasculature by suppressing the clutters is a significant and irreplaceable step for many applications of ultrasound CFI. Currently, this task is often performed by singular value decomposition (SVD) of the data matrix. This approach exhibits two well-known limitations. First, the performance of SVD is sensitive to the proper manual selection of the ranks corresponding to clutter and blood subspaces. Second, SVD is prone to failure in the presence of large random noise in the dataset. A potential solution to these issues is using decomposition into low-rank and sparse matrices (DLSM) framework. SVD is one of the algorithms for solving the minimization problem under the DLSM framework. Many other algorithms under DLSM avoid full SVD and use approximated SVD or SVD-free ideas which may have better performance with higher robustness and less computing time. In practice, these models separate blood from clutter based on the assumption that steady clutter represents a low-rank structure and that the moving blood component is sparse. In this paper, we present a comprehensive review of ultrasound clutter suppression techniques and exploit the feasibility of low-rank and sparse decomposition schemes in ultrasound clutter suppression. We conduct this review study by adapting 106 DLSM algorithms and validating them against simulation, phantom, and in vivo rat datasets. Two conventional quality metrics, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), are used for performance evaluation. In addition, computation times required by different algorithms for generating clutter suppressed images are reported. Our extensive analysis shows that the DLSM framework can be successfully applied to ultrasound clutter suppression.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Ultrassonografia , Algoritmos , Animais , Humanos , Razão Sinal-Ruído
6.
Plant Physiol Biochem ; 105: 260-270, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27173095

RESUMO

Salinity-stressed plants of salinity sensitive ('Qx096') and tolerant ('Qx097') chrysanthemum cultivar were treated with a range of concentrations of spermidine (Spd). Plant performance, as indicated by various parameters associated with growth, was improved by the treatment, as was the tissue content of soluble protein and proline. The extent of both Na(+) accumulation and K(+) loss was reduced. Activity levels of the stress-related enzymes SOD, POD, APX and CAT were significantly increased and the production of malondialdehyde (MDA) decreased. The suggestion was that treatment with 1.5 mM Spd would be an effective means alleviating salinity-stress induced injury through its positive effect on photosynthetic efficiency, reactive oxygen species scavenging ability and the control of ionic balance and osmotic potential. Its protective capacity was more apparent in 'Qx096' than in 'Qx097'.


Assuntos
Chrysanthemum/fisiologia , Salinidade , Plântula/fisiologia , Espermidina/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Antioxidantes/metabolismo , Chrysanthemum/efeitos dos fármacos , Chrysanthemum/enzimologia , Chrysanthemum/crescimento & desenvolvimento , Eletrólitos/metabolismo , Malondialdeído/metabolismo , Fotossíntese/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Potássio/metabolismo , Prolina/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sódio/metabolismo , Solubilidade
7.
Org Lett ; 16(21): 5600-3, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25338129

RESUMO

Linear iodoniums are widely used as arylating reagents. However, cyclic diaryl idodoniums are ignored despite their potential to initiate dual arylations, atom and step economically. In our current work, a three-component cascade reaction of cyclic diaryliodoniums, sodium azide, and alkynes has been successfully achieved under mild conditions, catalyzed by cheap copper species. The regioselectivity associated with unsymmetrical iodoniums was enhanced by installing two methyls ortho and para to the I(III) center. The reaction enables a rapid access to a variety of complex molecules, triazolophenanthridine derivatives.


Assuntos
Alcinos/química , Compostos de Bifenilo/química , Cobre/química , Oniocompostos/química , Fenantridinas/síntese química , Azida Sódica/química , Catálise , Estrutura Molecular , Fenantridinas/química
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