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1.
IEEE Trans Med Imaging ; 43(1): 149-161, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37436855

RESUMO

Automatic universal lesion segmentation (ULS) from Computed Tomography (CT) images can ease the burden of radiologists and provide a more accurate assessment than the current Response Evaluation Criteria In Solid Tumors (RECIST) guideline measurement. However, this task is underdeveloped due to the absence of large-scale pixel-wise labeled data. This paper presents a weakly-supervised learning framework to utilize the large-scale existing lesion databases in hospital Picture Archiving and Communication Systems (PACS) for ULS. Unlike previous methods to construct pseudo surrogate masks for fully supervised training through shallow interactive segmentation techniques, we propose to unearth the implicit information from RECIST annotations and thus design a unified RECIST-induced reliable learning (RiRL) framework. Particularly, we introduce a novel label generation procedure and an on-the-fly soft label propagation strategy to avoid noisy training and poor generalization problems. The former, named RECIST-induced geometric labeling, uses clinical characteristics of RECIST to preliminarily and reliably propagate the label. With the labeling process, a trimap divides the lesion slices into three regions, including certain foreground, background, and unclear regions, which consequently enables a strong and reliable supervision signal on a wide region. A topological knowledge-driven graph is built to conduct the on-the-fly label propagation for the optimal segmentation boundary to further optimize the segmentation boundary. Experimental results on a public benchmark dataset demonstrate that the proposed method surpasses the SOTA RECIST-based ULS methods by a large margin. Our approach surpasses SOTA approaches over 2.0%, 1.5%, 1.4%, and 1.6% Dice with ResNet101, ResNet50, HRNet, and ResNest50 backbones.


Assuntos
Radiologistas , Coluna Vertebral , Humanos , Critérios de Avaliação de Resposta em Tumores Sólidos , Bases de Dados Factuais , Tomografia Computadorizada por Raios X , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina Supervisionado
2.
Ecotoxicol Environ Saf ; 256: 114863, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37011512

RESUMO

Aluminum (Al) has been classified as a cumulative environmental pollutant that endangers human health. There is increasing evidence to suggest the toxic effects of Al, but the specific action on human brain development remains unclear. Al hydroxide (Al(OH)3), the most common vaccine adjuvant, is the major source of Al and poses risks to the environment and early childhood neurodevelopment. In this study, we explored the neurotoxic effect of 5 µg/ml or 25 µg/ml Al(OH)3 for six days on neurogenesis by utilizing human cerebral organoids from human embryonic stem cells (hESCs). We found that early Al(OH)3 exposure in organoids caused a reduction in the size, deficits in basal neural progenitor cell (NPC) proliferation, and premature neuron differentiation in a time and dose-dependent manner. Transcriptomes analysis revealed a markedly altered Hippo-YAP1 signaling pathway in Al(OH)3 exposed cerebral organoid, uncovering a novel mechanism for Al(OH)3-induced detrimental to neurogenesis during human cortical development. We further identified that Al(OH)3 exposure at day 90 mainly decreased the production of outer radial glia-like cells(oRGs) but promoted NPC toward astrocyte differentiation. Taken together, we established a tractable experimental model to facilitate a better understanding of the impact and mechanism of Al(OH)3 exposure on human brain development.


Assuntos
Células-Tronco Embrionárias Humanas , Células-Tronco Neurais , Pré-Escolar , Humanos , Hidróxido de Alumínio/metabolismo , Neurogênese , Organoides/metabolismo
3.
Biol Trace Elem Res ; 200(11): 4865-4879, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34973128

RESUMO

Selenium (Se) is an essential micronutrient with many beneficial effects for humans and other living organisms. Numerous microorganisms in culture systems enrich and convert inorganic selenium to organic selenium. In this study, Epichloë sp. from Festuca sinensis was exposed to increasing Na2SeO3 concentrations (0, 0.1, 0.2, 0.3, and 0.4 mmol/L) in Petri dishes with potato dextrose agar (PDA) for 8 weeks. Epichloë sp. mycelia were immediately collected after mycelial diameters were measured at 4, 5, 6, 7, and 8 weeks of cultivation, respectively. Gas chromatography-mass spectrometer (GC-MS) analysis was performed on different groups of Epichloë sp. mycelia. Different changes were observed as Epichloë sp. was exposed to different selenite conditions and cultivation time. The colony diameter of Epichloë sp. decreased in response to increased selenite concentrations, whereas the inhibitory effects diminished over time. Seventy-two of the 203 identified metabolites did not differ significantly across selenite treatments within the same time point, while 82 compounds did not differ significantly between multiple time points of the same Se concentration. However, the relative levels of 122 metabolites increased the most under selenite conditions. Specifically, between the 4th and 8th weeks, there were increases in 2-keto-isovaleric acid, uridine, and maltose in selenite treatments compared to controls. Selenium increased glutathione levels and exhibited antioxidant properties in weeks 4, 5, and 7. Additionally, we observed that different doses of selenite could promote the production of carbohydrates such as isomaltose, cellobiose, and sucrose; fatty acids such as palmitoleic acid, palmitic acid, and stearic acid; and amino acids such as lysine and tyrosine in Epichloë sp. mycelia. Therefore, Epichloë sp. exposed to selenite stress may benefit from increased levels of some metabolite compounds.


Assuntos
Epichloe , Festuca , Selênio , Ágar , Antioxidantes/farmacologia , Celobiose , Epichloe/química , Epichloe/metabolismo , Ácidos Graxos , Festuca/metabolismo , Glucose , Glutationa , Humanos , Isomaltose , Lisina , Maltose , Micronutrientes , Ácidos Palmíticos , Ácido Selenioso , Selênio/metabolismo , Selênio/farmacologia , Selenito de Sódio/metabolismo , Selenito de Sódio/farmacologia , Ácidos Esteáricos , Sacarose , Tirosina , Uridina
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