11 research outputs found
Pulse evolution in fiber nonlinear amplifier.mp4
The media based on simulauiton result describes how the pump wave and Stokes wave evolve in the fiber nonlinear amplifier. The pump wave is a Guassian pulse whereas the Stokes wave is a NLP originated from scattered noise.The spectrum evolution of the NLP is also exhibited
High repetition frequency mode-locked semiconductor disk laser
A compact passively mode-locked semiconductor disk laser with a high repetition frequency of 3GHz is demonstrated. 4.9ps pulse duration and 30mW average output power are obtained with 1.4W of 808nm incident pump power. The gain chip consists of 16 compressively strained InGaAs symmetrical step quantum wells in the active region
Supplementary document for Internal motion within ultrafast asynchronous dual wavelength mode-locked laser - 6774690.pdf
Repeated measurements show that the formation dynamics of the ground-state soliton molecule can be considerably different
Phenoxyaromatic Acid Analogues as Novel Radiotherapy Sensitizers: Design, Synthesis and Biological Evaluation
Radiotherapy is a vital approach for brain tumor treatment. The standard treatment for glioblastoma (GB) is maximal surgical resection combined with radiotherapy and chemotherapy. However, the non-sensitivity of tumor cells in the hypoxic area of solid tumors to radiotherapy may cause radioresistance. Therefore, radiotherapy sensitizers that increase the oxygen concentration within the tumor are promising for increasing the effectiveness of radiation. Inspired by hemoglobin allosteric oxygen release regulators, a series of novel phenoxyacetic acid analogues were designed and synthesized. A numerical method was applied to determine the activity and safety of newly synthesized compounds. In vitro studies on the evaluation of red blood cells revealed that compounds 19c (∆P50 = 45.50 mmHg) and 19t (∆P50 = 44.38 mmHg) improve the oxygen-releasing property effectively compared to positive control efaproxiral (∆P50 = 36.40 mmHg). Preliminary safety evaluation revealed that 19c exhibited no cytotoxicity towards HEK293 and U87MG cells, while 19t was cytotoxic toward both cells with no selectivity. An in vivo activity assay confirmed that 19c exhibited a radiosensitization effect on orthotopically transplanted GB in mouse brains. Moreover, a pharmacokinetic study in rats showed that 19c was orally available
Mutations in FLS2 Ser-938 Dissect Signaling Activation in FLS2-Mediated Arabidopsis Immunity
<div><p>FLAGELLIN-SENSING 2 (FLS2) is a leucine-rich repeat/transmembrane domain/protein kinase (LRR-RLK) that is the plant receptor for bacterial flagellin or the flagellin-derived flg22 peptide. Previous work has shown that after flg22 binding, FLS2 releases BIK1 kinase and homologs and associates with BAK1 kinase, and that FLS2 kinase activity is critical for FLS2 function. However, the detailed mechanisms for activation of FLS2 signaling remain unclear. The present study initially identified multiple FLS2 in vitro phosphorylation sites and found that Serine-938 is important for FLS2 function in vivo. FLS2-mediated immune responses are abolished in transgenic plants expressing <i>FLS2<sub>S938A</sub></i>, while the acidic phosphomimic mutants FLS2<sub>S938D</sub> and FLS2<sub>S938E</sub> conferred responses similar to wild-type FLS2. FLS2-BAK1 association and FLS2-BIK1 disassociation after flg22 exposure still occur with FLS2<sub>S938A</sub>, demonstrating that flg22-induced BIK1 release and BAK1 binding are not sufficient for FLS2 activity, and that Ser-938 controls other aspects of FLS2 activity. Purified BIK1 still phosphorylated purified FLS2<sub>S938A</sub> and FLS2<sub>S938D</sub> mutant kinase domains in vitro. Phosphorylation of BIK1 and homologs after flg22 exposure was disrupted in transgenic <i>Arabidopsis thaliana</i> plants expressing <i>FLS2<sub>S938A</sub></i> or <i>FLS2<sub>D997A</sub></i> (a kinase catalytic site mutant), but was normally induced in FLS2<sub>S938D</sub> plants. BIK1 association with FLS2 required a kinase-active FLS2, but FLS2-BAK1 association did not. Hence FLS2-BIK1 dissociation and FLS2-BAK1 association are not sufficient for FLS2-mediated defense activation, but the proposed FLS2 phosphorylation site Ser-938 and FLS2 kinase activity are needed both for overall defense activation and for appropriate flg22-stimulated phosphorylation of BIK1 and homologs.</p> </div
Interaction of BAK1 or BIK1 with variants of FLS2.
<p>HA-tagged full-length FLS2 wild type (WT), S938A, S938D or D997A (as labeled), and cMyc-tagged full length BAK1 or BIK1, were coexpressed under control of <i>35S</i> promoters in Arabidopsis <i>fls2-101</i> protoplasts. Protoplasts were harvested prior to (−) or 15 min. after (+) treatment with 1 µM flg22. Coimmunoprecipitation was carried out using anti-cMyc antibody. Input blots are from SDS-PAGE of total protein extracts; each lane was loaded with equivalent volumes of total protoplasts. WB: antibody used to probe immunoblot. <b>A.</b> FLS2<sub>WT</sub>, FLS2<sub>S938A</sub> and FLS2<sub>S938D</sub> interact with BAK1 upon flg22 treatment. <b>B.</b> BIK1 dissociates from FLS2<sub>WT</sub>, FLS2<sub>S938A</sub> and FLS2<sub>S938D</sub> after flg22 treatment. <b>C.</b> FLS2-FLS2 association before and after flg22 exposure is not reduced when both FLS2 partners carry the <i>FLS2<sub>S938A</sub></i> mutation. FLS2-BAK1 interaction from the same experiment is shown as a control (all six lanes in C from same protoplast batch, gel, blot and immunodetection). <b>D.</b> FLS2<sub>D997A</sub> interacts with BAK<sub>D416A</sub> upon flg22 treatment. FLS2<sub>D997A</sub> does not interact as well as FLS2<sub>WT</sub> with BIK1<sub>D202A</sub> before flg22 treatment, and flg22-elicited release of BIK1 is not detected. <b>E.</b> FLS2<sub>S938D</sub>, and separately, FLS2<sub>D997A</sub>, form FLS2-FLS2 associations before and after flg22 treatment.</p
Identification of Ser-938 as a candidate autophosphorylation site of FLS2 <i>in vitro</i> and <i>in vivo</i>.
<p><b>A</b> and <b>B.</b> Intact (A) and antarctic phosphatase-treated (B) intracellular domains of FLS2 (aa #840-1172) were analyzed by Mass Spectrometry (MS). M: predicted molecular weight; 1P: predicted peptide with one phosphate group; 2P: predicted peptide with two phosphate groups. <b>C.</b> Peptides containing phosphorylated amino acids, identified by mass spectrometry (see also <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003313#ppat.1003313.s001" target="_blank">Figure S1</a>). <b>D–F.</b> Functional test of three serine sites identified by MS. Reactive oxygen species were measured in leaf discs from transgenic Arabidopsis <i>fls2-101</i> plants for 30 min. after treatment with 1 µM flg22. Stable transgenic plants carried <i>FLS2</i> serine mutant alleles as specified, with expression driven by native <i>FLS2</i> promoter. Data shown are mean ± SE for four to six independent T1 plants per construct. RLU: relative luminescence units; wt: wild-type Col-0 FLS2; S938A: FLS2<sub>S938A</sub>; other <i>FLS2</i> alleles similarly labeled.</p
Induced phosphorylation of BIK1 and its homologous proteins under flg22 treatment.
<p>cMyc tagged BIK1, PBS1, PBL1, and PBL2 were transiently expressed (under control of 35S promoters) in protoplasts made from Arabidopsis <i>fls2-101</i> lines stably transgenic for full-length <i>FLS2<sub>WT</sub></i>, <i>FLS2<sub>S938A</sub></i>, <i>FLS2<sub>S938D</sub></i>, and <i>FLS2</i><sub>D997A</sub> (under control of <i>FLS2</i> promoters; <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003313#ppat.1003313.s002" target="_blank">Figure S2A</a>). Protoplasts were treated with (+) or without (−) 1 µM flg22 for 15 min prior to harvest. Total protein extracts were separated by SDS-PAGE and immunoblots were probed with anti-cMyc to detect protein size shift attributable to phosphorylation. Lower panel of each pair shows Ponceau S staining of same immunoblot to assess similarity of total protein levels.</p