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1.
Nat Commun ; 15(1): 3990, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734685

RESUMO

The path of tokamak fusion and International thermonuclear experimental reactor (ITER) is maintaining high-performance plasma to produce sufficient fusion power. This effort is hindered by the transient energy burst arising from the instabilities at the boundary of plasmas. Conventional 3D magnetic perturbations used to suppress these instabilities often degrade fusion performance and increase the risk of other instabilities. This study presents an innovative 3D field optimization approach that leverages machine learning and real-time adaptability to overcome these challenges. Implemented in the DIII-D and KSTAR tokamaks, this method has consistently achieved reactor-relevant core confinement and the highest fusion performance without triggering damaging bursts. This is enabled by advances in the physics understanding of self-organized transport in the plasma edge and machine learning techniques to optimize the 3D field spectrum. The success of automated, real-time adaptive control of such complex systems paves the way for maximizing fusion efficiency in ITER and beyond while minimizing damage to device components.

2.
Nature ; 609(7926): 269-275, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36071190

RESUMO

Nuclear fusion is one of the most attractive alternatives to carbon-dependent energy sources1. Harnessing energy from nuclear fusion in a large reactor scale, however, still presents many scientific challenges despite the many years of research and steady advances in magnetic confinement approaches. State-of-the-art magnetic fusion devices cannot yet achieve a sustainable fusion performance, which requires a high temperature above 100 million kelvin and sufficient control of instabilities to ensure steady-state operation on the order of tens of seconds2,3. Here we report experiments at the Korea Superconducting Tokamak Advanced Research4 device producing a plasma fusion regime that satisfies most of the above requirements: thanks to abundant fast ions stabilizing the core plasma turbulence, we generate plasmas at a temperature of 100 million kelvin lasting up to 20 seconds without plasma edge instabilities or impurity accumulation. A low plasma density combined with a moderate input power for operation is key to establishing this regime by preserving a high fraction of fast ions. This regime is rarely subject to disruption and can be sustained reliably even without a sophisticated control, and thus represents a promising path towards commercial fusion reactors.

3.
Ann Oncol ; 25(11): 2272-2277, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25149706

RESUMO

BACKGROUND: An exploratory translational analysis was conducted as part of a phase II study of dovitinib to assess the relevance of soluble serum proteins and circulating tumor (ct) DNA (ctDNA) as biomarkers in patients with tyrosine kinase inhibitor (TKI)-refractory gastrointestinal stromal tumors (GISTs). PATIENTS AND METHODS: Predose serum samples were collected from 30 patients on day 1 of cycle 1 and cycle 2. Serum levels of angiogenesis-related proteins were assessed by enzyme-linked immunosorbent assay, and Beads, emulsions, amplification, and magnetics (BEAMing) assays were carried out to detect mutations in serum ctDNA. RESULTS: Dovitinib increased vascular endothelial growth factor (VEGF)165 (1.26-fold, P = 0.006), VEGF-A (1.27-fold, P = 0.004), placental growth factor (6.0-fold, P = 0.002), fibroblast growth factor 23 (1.45-fold, P = 0.02), and interleukin 8 (1.75-fold, P = 0.04) levels, and decreased soluble vascular endothelial growth factor receptor (sVEGFR)-2 levels (0.8-fold, P = 0.001). The changes in sVEGFR-2 were significantly associated with metabolic response determined by positron emission tomography (P = 0.02) and progression-free survival (PFS; P = 0.02). Secondary kinase mutations were identified in the ctDNA of 11 patients (41%), and these patients all had mutations involving KIT exon 17. Patients with secondary KIT mutations had significantly worse overall survival {median, 5.5 months [95% confidence interval (CI) 3.8-7.2 months]} than those with no detectable secondary mutations [9.8 months (95% CI 9.6-10.0 months); hazard ratio = 2.7 (95% CI 1.0-7.3); P = 0.047]. CONCLUSIONS: Changes in sVEGFR-2 levels were associated with dovitinib-mediated antitumor activity. Genotyping of serum ctDNA with BEAMing is useful for the identification of resistant mutations potentially associated with poor prognosis in patients with GISTs.


Assuntos
Benzimidazóis/administração & dosagem , Biomarcadores Tumorais/sangue , Tumores do Estroma Gastrointestinal/sangue , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Quinolonas/administração & dosagem , Adulto , Idoso , DNA de Neoplasias/sangue , DNA de Neoplasias/genética , Intervalo Livre de Doença , Feminino , Tumores do Estroma Gastrointestinal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Células Neoplásicas Circulantes/patologia , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/sangue , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-kit/sangue , Proteínas Proto-Oncogênicas c-kit/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/sangue , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Fator A de Crescimento do Endotélio Vascular/sangue , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/sangue
4.
Cell Death Dis ; 5: e1224, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24832596

RESUMO

Interferon consensus sequence-binding protein (ICSBP) is a transcription factor induced by interferon gamma (IFN-γ) and a member of the interferon regulatory factor (IRF) family. ICSBP is predominantly expressed in hematopoietic cells and regulates the immune response and cell growth and differentiation. However, little is known about its function in non-hematopoietic cells. Here we show a novel function for ICSBP in epithelial-to-mesenchymal transition (EMT)-like phenomena (ELP), cell motility, and invasion in human osteosarcoma cell lines, including U2OS cells. IFN-γ treatment induced ICSBP expression and EMT-like morphological change in U2OS cells, which were suppressed by ICSBP knockdown. To further investigate the role of ICSBP in ELP, we established a stable U2OS cell line that overexpresses ICSBP. ICSBP expression caused U2OS cells to have a more elongated shape and an increased vimentin and fibronectin expression. ICSBP expression also promoted adhesiveness, motility, and invasiveness of U2OS cells. ICSBP upregulated transforming growth factor (TGF)-ß receptors and activated TGF-ß signaling cascades, which were responsible for ELP as well as increased cell motility and invasion. In addition, ICSBP-induced TGF-ß receptor activation resulted in the upregulation of Snail. Knockdown of Snail attenuated the ICSBP-induced augmentation of cell motility and invasion. Upregulation of Snail, ELP, and increased invasion by ICSBP expression were also observed in other osteosarcoma cell lines, such as Saos-2 and 143B. Furthermore, ICSBP and TGF-ß receptor I were expressed in 45/54 (84%) and 47/54 (87%) of human osteosarcoma tissues, respectively, and showed significant correlation (r=0.47, P=0.0007) with respect to their expression levels. Taken altogether, these data demonstrate a novel function for ICSBP in ELP, cell motility, and invasion through the TGF-ß and Snail signaling pathways.


Assuntos
Neoplasias Ósseas/metabolismo , Movimento Celular , Transição Epitelial-Mesenquimal , Fatores Reguladores de Interferon/metabolismo , Osteossarcoma/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Antígenos CD , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Caderinas/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Forma Celular , Técnicas de Cocultura , Fibronectinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fatores Reguladores de Interferon/genética , Interferon gama/metabolismo , Invasividade Neoplásica , Osteossarcoma/genética , Osteossarcoma/patologia , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fatores de Transcrição da Família Snail , Fatores de Tempo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Vimentina/metabolismo
5.
Lett Appl Microbiol ; 34(6): 389-93, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12028416

RESUMO

AIMS: The objective of the study was to optimize the submerged culture conditions for the production of exopolysaccharide from Paecilomyces sinclairii. METHODS AND RESULTS: The optimal temperature and initial pH for exopolysaccharide production by Paecilomyces sinclairii in shake flask culture were found to be 30 degrees C and 6.0, respectively. Sucrose (60 g l(-1)) and corn steep powder (10 g l(-1)) were the most suitable carbon and nitrogen source for exopolysaccharide production. CONCLUSIONS: Under optimal culture medium, the maximum exopolysaccharide concentration in a 5-l stirred-tank fermenter indicated 7.4 g l(-1), which was approximately three times higher than that in basal medium. The maximum specific growth rates (micro max) and yield coefficient (Y(P/S)) in the optimal culture medium was 0.16 h(-1) and 0.19, respectively. SIGNIFICANCE AND IMPACT OF THE STUDY: The optimal culture conditions reported in this article can be widely applied to the processes for submerged cultures of other mushrooms.


Assuntos
Paecilomyces/metabolismo , Polissacarídeos/metabolismo , Carbono/metabolismo , Técnicas de Cultura de Células/métodos , Meios de Cultura , Fermentação , Concentração de Íons de Hidrogênio , Minerais/metabolismo , Nitrogênio/metabolismo , Paecilomyces/crescimento & desenvolvimento , Temperatura
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