scholarly journals Role of phase instabilities in the early response of bulk fused silica during laser-induced breakdown

2011 ◽  
Vol 84 (5) ◽  
Author(s):  
P. DeMange ◽  
R. A. Negres ◽  
R. N. Raman ◽  
J. D. Colvin ◽  
S. G. Demos
Keyword(s):  
Early Response ◽  
Fused Silica ◽  
Laser Induced Breakdown ◽  
Phase Instabilities

Femtosecond laser pulse-train induced breakdown in fused silica: the role of seed electrons

2014 ◽  
Vol 47 (43) ◽  
pp. 435105 ◽  
Author(s):  
Kaihu Zhang ◽  
Lan Jiang ◽  
Xin Li ◽  
Xuesong Shi ◽  
Dong Yu ◽  
...  
Keyword(s):  
Laser Pulse ◽  
Femtosecond Laser ◽  
Femtosecond Laser Pulse ◽  
Pulse Train ◽  
Fused Silica

The role of cavity shape on spatially confined laser-induced breakdown spectroscopy

2018 ◽  
Vol 25 (7) ◽  
pp. 073301 ◽  
Author(s):  
Qiuyun Wang ◽  
Anmin Chen ◽  
Dan Zhang ◽  
Ying Wang ◽  
Laizhi Sui ◽  
...  
Keyword(s):  
Laser Induced Breakdown Spectroscopy ◽  
Cavity Shape ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown

scholarly journals Surface Chemical Differences Between Sweetpotato Lines with Varying Levels of Resistance to the Sweetpotato Weevil

1990 ◽  
Vol 115 (4) ◽  
pp. 696-699 ◽  
Author(s):  
Ki-Cheol Son ◽  
Ray F. Severson ◽  
Richard F. Arrendale ◽  
Stanley J. Kays
Keyword(s):  
Ipomoea Batatas ◽  
Methylene Chloride ◽  
Chemical Characterization ◽  
Fused Silica ◽  
Storage Roots ◽  
Sweetpotato Weevil ◽  
Or Groups ◽  
Fused Silica Capillary ◽  
Silica Capillary Column

Methodology was developed for the extraction of surface components of sweetpotato [Ipomoea batatas (L.) Lam.] storage roots. Surface components of storage roots were quantitatively extracted with methylene chloride using 8-minute ultrasonication. After removal of the solvent, the extract was treated with 3 Tri Sil-Z:1 trimethylsilylimidazol (v/v) to convert components with hydroxyl moieties to silyl ethers and then separated on a SE-54 fused silica capillary column. Distinctly different gas chromatography profiles were found between lines displaying moderate levels of resistance (`Resisto', `Regal', `Jewel') to the sweetpotato weevil [Cylas formicarius elgantulus (summers)] and weevil-susceptible lines (`Centennial', SC 1149-19, W-115), indicating a possible role of surface components in insect response. Chromatographic fractionation techniques were developed for separation of major components or groups of components. The results will allow subsequent bioassaying for the presence of an ovipositional stimulant(s) and other weevil behavior-modulating compounds and their chemical characterization.

scholarly journals Dram1 confers resistance to Salmonella infection

2021 ◽  
Author(s):  
Samrah Masud ◽  
Rui Zhang ◽  
Tomasz K. Prajsnar ◽  
Annemarie H. Meijer
Keyword(s):  
Defense Mechanism ◽  
Early Response ◽  
Protective Role ◽  
Infection Model ◽  
Transgenic Zebrafish ◽  
Functional Link ◽  
Morpholino Knockdown ◽  
Host Defense Mechanism ◽  
Important Host

Dram1 is a stress and infection inducible autophagy modulator that functions downstream of transcription factors p53 and NFκB. Using a zebrafish embryo infection model, we have previously shown that Dram1 provides protection against the intracellular pathogen Mycobacterium marinum by promoting the p62-dependent xenophagy of bacteria that have escaped into the cytosol. However, the possible interplay between Dram1 and other anti-bacterial autophagic mechanisms remains unknown. Recently, LC3-associated phagocytosis (LAP) has emerged as an important host defense mechanism that requires components of the autophagy machinery and targets bacteria directly in phagosomes. Our previous work established LAP as the main autophagic mechanism by which macrophages restrict growth of Salmonella Typhimurium in a systemically infected zebrafish host. We therefore employed this infection model to investigate the possible role of Dram1 in LAP. Morpholino knockdown or CRISPR/Cas9-mediated mutation of Dram1 led to reduced host survival and increased bacterial burden during S. Typhimurium infections. In contrast, overexpression of dram1 by mRNA injection curtailed Salmonella replication and reduced mortality of the infected host. During the early response to infection, GFP-Lc3 levels in transgenic zebrafish larvae correlated with the dram1 expression level, showing over two-fold reduction of GFP-Lc3-Salmonella association in dram1 knockdown or mutant embryos and an approximately 30% increase by dram1 overexpression. Since LAP is known to require the activity of the phagosomal NADPH oxidase, we used a Salmonella biosensor strain to detect bacterial exposure to reactive oxygen species (ROS) and found that the ROS response was largely abolished in the absence of dram1. Together, these results demonstrate the host protective role of Dram1 during S. Typhimurium infection and suggest a functional link between Dram1 and the induction of LAP.

A role for the vegetally expressed Xenopus gene Mix.1 in endoderm formation and in the restriction of mesoderm to the marginal zone

Development ◽  
1998 ◽  
Vol 125 (13) ◽  
pp. 2371-2380 ◽  
Author(s):  
P. Lemaire ◽  
S. Darras ◽  
D. Caillol ◽  
L. Kodjabachian
Keyword(s):  
Marginal Zone ◽  
Ectopic Expression ◽  
Homeobox Gene ◽  
Early Response ◽  
Endoderm Differentiation ◽  
Head Formation ◽  
Mutual Repression ◽  
Regulatory Loop ◽  
Strong Activator

We have studied the role of the activin immediate-early response gene Mix.1 in mesoderm and endoderm formation. In early gastrulae, Mix.1 is expressed throughout the vegetal hemisphere, including marginal-zone cells expressing the trunk mesodermal marker Xbra. During gastrulation, the expression domains of Xbra and Mix.1 become progressively exclusive as a result of the establishment of a negative regulatory loop between these two genes. This mutual repression is important for the specification of the embryonic body plan as ectopic expression of Mix.1 in the Xbra domain suppresses mesoderm differentiation. The same effect was obtained by overexpressing VP16Mix.1, a fusion protein comprising the strong activator domain of viral VP16 and the homeodomain of Mix.1, suggesting that Mix.1 acts as a transcriptional activator. Mix.1 also has a role in endoderm formation. It cooperates with the dorsal vegetal homeobox gene Siamois to activate the endodermal markers edd, Xlhbox8 and cerberus in animal caps. Conversely, vegetal overexpression of enRMix.1, an antimorphic Mix.1 mutant, leads to a loss of endoderm differentiation. Finally, by targeting enRMix.1 expression to the anterior endoderm, we could test the role of this tissue during embryogenesis and show that it is required for head formation.

scholarly journals Role of Nurr1 in Carcinogenesis and Tumor Immunology: A State of the Art Review

Cancers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 3044 ◽  
Author(s):  
Peter Kok-Ting Wan ◽  
Michelle Kwan-Yee Siu ◽  
Thomas Ho-Yin Leung ◽  
Xue-Tang Mo ◽  
Karen Kar-Loen Chan ◽  
...  
Keyword(s):  
T Cells ◽  
Immune Responses ◽  
Antitumor Immunity ◽  
Cytotoxic T Cells ◽  
Early Response ◽  
Downstream Signaling ◽  
Wide Range ◽  
Immunotherapeutic Strategy ◽  
Poor Efficacy

Nuclear receptor related-1 protein (Nurr1), coded by an early response gene, is involved in multiple cellular and physiological functions, including proliferation, survival, and self-renewal. Dysregulation of Nurr1 has been frequently observed in many cancers and is attributed to multiple transcriptional and post-transcriptional mechanisms. Besides, Nurr1 exhibits extensive crosstalk with many oncogenic and tumor suppressor molecules, which contribute to its potential pro-malignant behaviors. Furthermore, Nurr1 is a key player in attenuating antitumor immune responses. It not only potentiates immunosuppressive functions of regulatory T cells but also dampens the activity of cytotoxic T cells. The selective accessibility of chromatin by Nurr1 in T cells is closely associated with cell exhaustion and poor efficacy of cancer immunotherapy. In this review, we summarize the reported findings of Nurr1 in different malignancies, the mechanisms that regulate Nurr1 expression, and the downstream signaling pathways that Nurr1 employs to promote a wide range of malignant phenotypes. We also give an overview of the association between Nurr1 and antitumor immunity and discuss the inhibition of Nurr1 as a potential immunotherapeutic strategy.

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