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Breathing of dissipative light bullets of nonlinear polarization mode in Kerr resonators. OPTICS LETTERS 2022; 47:3652-3655. [PMID: 35913281 DOI: 10.1364/ol.455758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 07/03/2022] [Indexed: 06/15/2023]
Abstract
We demonstrate the existence of breathing dissipative light bullets in a birefringent optical resonator filled with Kerr media. The propagation of light inside the cavity for each polarized component, which is coupled by cross-phase modulation, is described by the coupled Lugiato-Lefever equations. The space-time dynamics of breathing light bullets are described using Stokes parameters and frequency spectra.
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2
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Relative Nuclease Resistance of a DNA Aptamer Covalently Conjugated to a Target Protein. Int J Mol Sci 2022; 23:ijms23147778. [PMID: 35887130 PMCID: PMC9319527 DOI: 10.3390/ijms23147778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/08/2022] [Accepted: 07/12/2022] [Indexed: 12/10/2022] Open
Abstract
A major obstacle to the therapeutic application of an aptamer is its susceptibility to nuclease digestion. Here, we confirmed the acquisition of relative nuclease resistance of a DNA-type thrombin binding aptamer with a warhead (TBA3) by covalent binding to a target protein in the presence of serum/various nucleases. When the thrombin-inhibitory activity of TBA3 on thrombin was reversed by the addition of the complementary strand, the aptamer was instantly degraded by the nucleases, showing that the properly folded/bound aptamer conferred the resistance. Covalently binding aptamers possessing both a prolonged drug effect and relative nuclease resistance would be beneficial for in vivo translational applications.
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3
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Solvatochromic peptidic binder obtained via extended phage display acts as a fluororeporter for fragment-based drug discovery (FBDD). Anal Bioanal Chem 2022; 414:4803-4807. [DOI: 10.1007/s00216-022-04128-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 05/09/2022] [Accepted: 05/11/2022] [Indexed: 11/29/2022]
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4
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Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study. ENVIRONMENT INTERNATIONAL 2022; 160:107069. [PMID: 34974237 DOI: 10.1016/j.envint.2021.107069] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 12/22/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We cannot rule out, however, residual confounding from sources we did not measure. Overall, our study provides no evidence of a causal association between wireless phone use and brain tumours in young people. However, the sources of bias summarised above prevent us from ruling out a small increased risk.
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A medium-firm drug-candidate library of cryptand-like structures on T7 phage: design and selection of a strong binder for Hsp90. Org Biomol Chem 2021; 19:146-150. [PMID: 33095213 DOI: 10.1039/d0ob01855d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We designed and synthesized a medium-firm drug-candidate library of cryptand-like structures possessing a randomized peptide linker on the bacteriophage T7. From the macrocyclic library with a 109 diversity, we obtained a binder toward a cancer-related protein (Hsp90) with an antibody-like strong affinity (KD = 62 nM) and the binding was driven by the enthalpy. The selected supramolecular ligand inhibited Hsp90 activity by site-specific binding outside of the well-known ATP-binding pocket on the N-terminal domain (NTD).
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Listeriosis presenting with fever, arthralgia, elevated liver enzymes, and hyperferritinaemia in pregnancy: a critical mimicker of adult-onset Still's disease. Scand J Rheumatol 2021; 51:78-80. [PMID: 34152237 DOI: 10.1080/03009742.2021.1923149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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7
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Direct screening of a target-specific covalent binder: stringent regulation of warhead reactivity in a matchmaking environment. Chem Commun (Camb) 2021; 57:5378-5381. [PMID: 33978001 DOI: 10.1039/d1cc01773j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A peptide-type covalent binder for a target protein was obtained by direct and stringent screening of a warhead-modified peptide library on the robust T7 phage. The aryl fluorosulfate (fosylate) warhead was activated only in a matchmaking microenvironment created between the target protein and an appropriate peptide during the reactivity/affinity-based co-selection process of extended phage display.
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Dissipative Light Bullets in Kerr Cavities: Multistability, Clustering, and Rogue Waves. PHYSICAL REVIEW LETTERS 2021; 126:153902. [PMID: 33929226 DOI: 10.1103/physrevlett.126.153902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 02/03/2021] [Accepted: 03/19/2021] [Indexed: 06/12/2023]
Abstract
We report the existence of stable dissipative light bullets in Kerr cavities. These three-dimensional (3D) localized structures consist of either an isolated light bullet (LB), bound together, or could occur in clusters forming well-defined 3D patterns. They can be seen as stationary states in the reference frame moving with the group velocity of light within the cavity. The number of LBs and their distribution in 3D settings are determined by the initial conditions, while their maximum peak power remains constant for a fixed value of the system parameters. Their bifurcation diagram allows us to explain this phenomenon as a manifestation of homoclinic snaking for dissipative light bullets. However, when the strength of the injected beam is increased, LBs lose their stability and the cavity field exhibits giant, short-living 3D pulses. The statistical characterization of pulse amplitude reveals a long tail probability distribution, indicating the occurrence of extreme events, often called rogue waves.
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Inhibition of thrombin activity by a covalent-binding aptamer and reversal by the complementary strand antidote. Chem Commun (Camb) 2021; 57:2483-2486. [PMID: 33625415 DOI: 10.1039/d0cc08109d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Alleviating the potential risk of irreversible adverse drug effects has been an important and challenging issue for the development of covalent drugs. Here we created a DNA-aptamer-type covalent drug by introducing a sulfonyl fluoride warhead at appropriate positions of the thrombin binding aptamer to create weaponized covalent drugs. We showed the de-activation of thrombin by the novel modality, followed by its re-activation by the complementary strand antidote at an arbitrary time. We envision that such on-demand reversal of covalent drugs will alleviate the major concern of potentially irreversible ADEs and accelerate the translational application of covalent aptamer drugs.
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Strategic design to create HER2-targeting proteins with target-binding peptides immobilized on a fibronectin type III domain scaffold. RSC Adv 2020; 10:15154-15162. [PMID: 35495466 PMCID: PMC9052545 DOI: 10.1039/d0ra00427h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 04/05/2020] [Indexed: 11/21/2022] Open
Abstract
Tumor-binding peptides such as human epidermal growth factor receptor 2 (HER2)-binding peptides are attractive therapeutic and diagnostic options for cancer. However, the HER2-binding peptides (HBPs) developed thus far are susceptible to proteolysis and lose their affinity to HER2 in vivo. In this report, a method to create a HER2-binding fluctuation-regulated affinity protein (HBP-FLAP) consisting of a fibronectin type III domain (FN3) scaffold with a structurally immobilized HBP is presented. HBPs were selected by phage-library screening and grafted onto FN3 to create FN3-HBPs, and the HBP-FLAP with the highest affinity (HBP sequence: YCAHNM) was identified after affinity maturation of the grafted HBP. HBP-FLAP containing the YCAHNM peptide showed increased proteolysis-resistance, binding to HER2 with a dissociation constant (KD) of 58 nM in ELISA and 287 nM in biolayer interferometry and specifically detects HER2-expressing cancer cells. In addition, HBP-FLAP clearly delineated HER2-expressing tumors with a half-life of 6 h after intravenous injection into tumor-bearing mice. FN3-based FLAP is an excellent platform for developing target-binding small proteins for clinical applications. A HER2-binding protein, HBP-FLAP, developed by peptide immobilization specifically binds to HER2 and has improved resistance to proteases.![]()
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11
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Mechano-chromic protein-polymer hybrid hydrogel to visualize mechanical strain. SOFT MATTER 2019; 15:9388-9393. [PMID: 31609367 DOI: 10.1039/c9sm00380k] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In a proof-of-concept study, a mechano-chromic hydrogel was synthesized here, via chemoenzymatic click conjugation of fluorophore-labeled fibronectin into a synthetic hydrogel co-polymers (i.e., poly-N-isopropylacrylamide/polyethylene glycol). The optical FRET response could be tuned by macroscopic stretch.
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12
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P2696Clinical characteristics of late catch-up phenomenon after implantation of 2nd generation drug eluting stent. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.1013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
Late catch-up phenomenon (LCU) of 1st generation drug eluting stent (DES) has been increasing yearly despite the rate of restenosis in 1 year has reduced compared with bare metal stent (BMS). 2nd generation DES was more improved than 1st generation DES and suggested more benefits about clinical outcome.
Purpose
To investigate the incidence and predictor of LCU after implantation of 2nd generation DES and to evaluate the association between LCU phenomenon and adverse events.
Methods
Between August 2012 and July 2013, a total of 1665 consecutive patients (1956 lesions with elective/urgent PCI) were enrolled in SHINANO 5 years Registry (a prospective observational multicenter cohort study) from 13 institutions in Nagano, Japan. 711 patients that were treated with 2nd generation DES and 576 patients with BMS were selected. Exclusion criterias were cases of 1st DES, only POBA, only aspiration and chronic total occulusion.
Results
There were significant difference about patients background between BMS and 2nd generation DES groups. Those groups were matched with propensity score. After matching, 822 patients (BMS group 411 patients, 2nd generation group 411 patients) were analyzed. The rates of 2nd DES and BMS restenosis 5 years after initial PCI were 9.2% and 8.5% (p=0.572), those of LCU were 2.6% and 5.6% (p=0.043) by 1 year landmark analysis. Cox proportional hazards analysis revealed that the DES in-stent restenosis (ISR) lesion and higher HbA1c were independent predictors for LCU from 1year to 5year (HR 5.304, p=0.009, HR 1.254, p=0.015), but 2nd generation DES was not. Kaplan Meier curve showed no association between LCU phenomenon and all cause death (p=0.446). Cox regression analysis showed LCU was not independent predictor for all cause death (p=0.414).
Conclusions
Implantation to DES-ISR lesion with 2nd generation DES was associated with higher LCU. Despite of more complex lesions with 2nd generation DES, there were no differences of LCU incidence between 2nd generation DES and BMS.
Acknowledgement/Funding
None
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Facile and Efficient Chemoenzymatic Semisynthesis of Fc-Fusion Compounds for Half-Life Extension of Pharmaceutical Components. Bioconjug Chem 2019; 30:2323-2331. [PMID: 31038930 DOI: 10.1021/acs.bioconjchem.9b00235] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The formation of Fc-fusions, in which biologically active molecules and the Fc fragment of antibodies are linked to each other, is one of the most efficient and successful half-life extension technologies to be developed and applied to peptide and protein pharmaceuticals thus far. Fc-fusion compounds are generally produced by recombinant methods. However, these cannot be applied to artificial middle molecules, such as peptides with non-natural amino acids, unnatural cyclic peptides, or pharmaceutical oligonucleotides. Here, we developed a simple, efficient, semisynthetic method for Fc-fusion production involving our previously developed enzymatic N-terminal extension reaction (i.e., NEXT-A reaction) and strain-promoted azide-alkyne cycloaddition, achieving quantitative conversion and high selectivity for the N-terminus of the Fc protein. An Fc-fusion compound prepared by this method showed comparable biological activity to that of the original peptide and a long-circulating plasma half-life. Thus, the proposed method is potentially applicable for the conjugation of a wide range of pharmaceutical components.
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A Cysteine-Reactive Small Photo-Crosslinker Possessing Caged-Fluorescence Properties: Binding-Site Determination of a Combinatorially-Selected Peptide by Fluorescence Imaging/Tandem Mass Spectrometry. Int J Mol Sci 2018; 19:E3682. [PMID: 30469338 PMCID: PMC6274937 DOI: 10.3390/ijms19113682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/15/2018] [Accepted: 11/16/2018] [Indexed: 11/17/2022] Open
Abstract
To determine the binding-site of a combinatorially-selected peptide possessing a fluoroprobe, a novel cysteine reactive small photo-crosslinker that can be excited by a conventional long-wavelength ultraviolet handlamp (365 nm) was synthesized via Suzuki coupling with three steps. The crosslinker is rationally designed, not only as a bioisostere of the fluoroprobe, but as a caged-fluorophore, and the photo-crosslinked target protein became fluorescent with a large Stokes-shift. By introducing the crosslinker to a designated sulfhydryl (SH) group of a combinatorially-selected peptide, the protein-binding site of the targeted peptide was deduced by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)/fluorescence imaging followed by matrix-assisted laser desorption ionization-time of flight tandem mass spectrometry (MALDI-TOF-MS/MS) analysis.
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15
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Fluorescent "keep-on" type pharmacophore obtained from dynamic combinatorial library of Schiff bases. Anal Bioanal Chem 2018; 410:6713-6717. [PMID: 30099565 DOI: 10.1007/s00216-018-1303-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 07/31/2018] [Indexed: 12/30/2022]
Abstract
We established a novel principle for fluorescence detection of a target protein. A low-molecular-weight fluorescent pharmacophore, as a targeted probe, was selected from a dynamic combinatorial library of Schiff bases. The pharmacophore retains its fluorescence when bound to the hydrophobic site of the target, whereas it loses it because of hydrolysis when unbound. Graphical abstract We describe a novel concept for detection of a target protein (i.e., HSA) by using a keep-on-type fluorescent pharmacophore which is discovered from a dynamic combinatorial library of Schiff bases. When the target is absent, the keep-on-pharmacophore is degraded by hydrolysis, with the result that we can see no fluorescence.
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16
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The Japanese Immune Tolerance Induction (J-ITI) study in haemophilia patients with inhibitor: Outcomes and successful predictors of ITI treatment. Haemophilia 2018; 24:e328-e337. [DOI: 10.1111/hae.13531] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/07/2018] [Indexed: 01/19/2023]
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17
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Combinatorially Screened Peptide as Targeted Covalent Binder: Alteration of Bait-Conjugated Peptide to Reactive Modifier. Bioconjug Chem 2018; 29:1866-1871. [PMID: 29792678 DOI: 10.1021/acs.bioconjchem.8b00301] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A peptide-type covalent binder for a target protein was obtained by combinatorial screening of fluoroprobe-conjugated peptide libraries on bacteriophage T7. The solvatochromic fluoroprobe works as a bait during the affinity selection process of phage display. To obtain the targeted covalent binder, the bait in the selected consensus peptide was altered into a reactive warhead possessing a sulfonyl fluoride. The reaction efficiency and site/position specificity of the covalent conjugation between the binder and the target protein were evaluated by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and rationalized by a protein-ligand docking simulation.
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18
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Characterization of spatiotemporal chaos in a Kerr optical frequency comb and in all fiber cavities. OPTICS LETTERS 2017; 42:1063-1066. [PMID: 28295092 DOI: 10.1364/ol.42.001063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Complex spatiotemporal dynamics have been a subject of recent experimental investigations in optical frequency comb microresonators and in driven fiber cavities with Kerr-type media. We show that this complex behavior has a spatiotemporal chaotic nature. We determine numerically the Lyapunov spectra, allowing us to characterize different dynamical behavior occurring in these simple devices. The Yorke-Kaplan dimension is used as an order parameter to characterize the bifurcation diagram. We identify a wide regime of parameters where the system exhibits a coexistence between the spatiotemporal chaos, the oscillatory localized structure, and the homogeneous steady state. The destabilization of an oscillatory localized state through radiation of counter-propagating fronts between the homogeneous and the spatiotemporal chaotic states is analyzed. To characterize better the spatiotemporal chaos, we estimate the front speed as a function of the pump intensity.
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19
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Extended and localized Hopf-Turing mixed-mode in non-instantaneous Kerr cavities. OPTICS EXPRESS 2017; 25:4714-4719. [PMID: 28380742 DOI: 10.1364/oe.25.004714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We investigate the spatio-temporal dynamics of a ring cavity filled with a non-instantaneous Kerr medium and driven by a coherent injected beam. We show the existence of a stable mixed-mode solution that can be either extended or localized in space. The mixed-mode solutions are obtained in a regime where Turing instability (often called modulational instability) interacts with self-pulsing phenomenon (Andronov-Hopf bifurcation). We numerically describe the transition from stationary inhomogeneous solutions to a branch of mixed-mode solutions. We characterize this transition by constructing the bifurcation diagram associated with these solutions. Finally, we show stable localized mixed-mode solutions, which consist of time-periodic oscillations that are localized in space.
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Editorial (Thematic Issue: Chemical and Biological Technology for In Vivo and Molecular Imaging). Curr Top Med Chem 2016. [DOI: 10.2174/1568026616999160517124310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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21
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18F-Containing Positron Emission Tomography Probe Conjugation Methodology for Biologics as Specific Binders for Tumors. Curr Top Med Chem 2016; 16:2703-24. [DOI: 10.2174/1568026616666160413125948] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 12/12/2015] [Accepted: 12/20/2015] [Indexed: 11/22/2022]
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22
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A phase III clinical trial of a mixture agent of plasma-derived factor VIIa and factor X (MC710) in haemophilia patients with inhibitors. Haemophilia 2016; 23:59-66. [DOI: 10.1111/hae.13050] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2016] [Indexed: 11/27/2022]
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23
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Editorial: Chemical and Biological Technology for In Vivo and Molecular Imaging. Curr Top Med Chem 2016:CTMC-EPUB-75746. [PMID: 27184145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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24
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Selection of Color-Changing and Intensity-Increasing Fluorogenic Probe as Protein-Specific Indicator Obtained via the 10BASE(d)-T. Anal Chem 2016; 88:1096-9. [PMID: 26727351 PMCID: PMC5077683 DOI: 10.1021/acs.analchem.5b04687] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To obtain a molecular probe for specific protein detection, we have synthesized fluorogenic probe library of vast diversity on bacteriophage T7 via the gp10 based-thioetherificaion (10BASE(d)-T). A remarkable color-changing and turning-on probe was selected from the library, and its physicochemical properties upon target-specific binding were obtained. Combination analyses of fluorescence emission titration, isothermal titration calorimetry (ITC), and quantitative saturation-transfer difference (STD) NMR measurements, followed by in silico docking simulation, rationalized the most plausible geometry of the ligand-protein interaction.
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25
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Editorial (Thematic Issue: Chemical and Biological Technology for In Vivo and Molecular Imaging). Curr Top Med Chem 2016; 16:2635-2637. [PMID: 27523815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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26
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Unexpectedly fast transfer of positron-emittable artificial substrate into N-terminus of peptide/protein mediated by wild-type L/F-tRNA-protein transferase. Amino Acids 2015; 47:1279-82. [PMID: 25929586 DOI: 10.1007/s00726-015-1989-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 04/14/2015] [Indexed: 01/09/2023]
Abstract
This article demonstrates the fastest enzymatic introduction of a positron emission tomography (PET) probe into acceptor peptides/proteins. It is site-specifically introduced at the basic N-terminus of the acceptors by using L/F-transferase in combination with aminoacyl-tRNA synthetase, namely the NEXT-A/PET reaction. Estimated from kinetic analysis, the transfer efficiency of O-(2-fluoromethyl)-L-tyrosine as an artificial amino acid PET probe mediated by the wild-type transferase is almost as good as that of the natural substrate, phenylalanine.
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Pharmacophore generation from a drug-like core molecule surrounded by a library peptide via the 10BASEd-T on bacteriophage T7. Molecules 2014; 19:2481-96. [PMID: 24566316 PMCID: PMC6271298 DOI: 10.3390/molecules19022481] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 02/10/2014] [Accepted: 02/12/2014] [Indexed: 11/16/2022] Open
Abstract
We have achieved site-specific conjugation of several haloacetamide derivatives into designated cysteines on bacteriophage T7-displayed peptides, which are fused to T7 capsid protein gp10. This easiest gp10 based-thioetherification (10BASEd-T) undergoes almost quantitatively like a click reaction without side reaction or loss of phage infectivity. The post-translational modification yield, as well as the site-specificity, is quantitatively analyzed by a fluorescent densitometric analysis after gel electrophoresis. The detailed structure of the modified peptide on phage is identified with tandem mass spectrometry. Construction of such a peptide-fused phage library possessing non-natural core structures will be useful for future drug discovery. For this aim, we propose a novel concept of pharmacophore generation from a drug-like molecule (i.e., salicylic acid) conjugated with surrounding randomized peptides. By using the hybrid library, streptavidin-specific binders are isolated through four rounds of biopanning.
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28
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Universal power law for front propagation in all fiber resonators. OPTICS EXPRESS 2014; 22:483-489. [PMID: 24515008 DOI: 10.1364/oe.22.000483] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We consider a bistable system consisting of all fiber cavity driven by an external injected continuous wave. We report on front propagation in a high finesse cavity. We study the asymptotic behavior of the front velocity. We show that the front velocity is affected by the distance from the critical point associated with bistability. We provide a scaling low governing its evolution near the up-switching point of the bistable curve. We show also that the velocity of front propagation obeys a generic power law when the front velocity approaches asymptotically its linear growing value.
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Construction of a crown ether-like supramolecular library by conjugation of genetically-encoded peptide linkers displayed on bacteriophage T7. Chem Commun (Camb) 2014; 50:3921-3. [DOI: 10.1039/c4cc00811a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
By using the 10BASEd-T, we have synthesized a crown ether-like macrocyclic library possessing randomized peptide linkers on bacteriophage T7.
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Hybrid Raman/Brillouin-optical-time-domain-analysis-distributed optical fiber sensors based on cyclic pulse coding. OPTICS LETTERS 2013; 38:4162-4165. [PMID: 24321949 DOI: 10.1364/ol.38.004162] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We experimentally demonstrate the use of cyclic pulse coding for distributed strain and temperature measurements in hybrid Raman/Brillouin optical time-domain analysis (BOTDA) optical fiber sensors. The highly integrated proposed solution effectively addresses the strain/temperature cross-sensitivity issue affecting standard BOTDA sensors, allowing for simultaneous meter-scale strain and temperature measurements over 10 km of standard single mode fiber using a single narrowband laser source only.
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Gp10 based-thioetherification (10BASE(d)-T) on a displaying library peptide of bacteriophage T7. MOLECULAR BIOSYSTEMS 2013; 9:2988-91. [PMID: 24072138 DOI: 10.1039/c3mb70379g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The site-specific introduction of a haloacetamide derivative into a designated cysteine on a displaying peptide on a capsid protein (gp10) of bacteriophage T7 has been achieved. This easiest gp10-based thioetherification (10BASEd-T) is carried out in one-pot without side reactions or loss of phage infectivity.
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Abstract
A cyclic pulse coding technique is proposed and experimentally demonstrated for fast implementation of long-range Brillouin optical time-domain analysis (BOTDA). The proposed technique allows for accurate temperature and strain measurements with meter-scale spatial resolution over kilometers of standard single-mode fiber, with subsecond measurement times.
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Kinetic analysis of the leucyl/phenylalanyl-tRNA-protein transferase with acceptor peptides possessing different N-terminal penultimate residues. FEBS Open Bio 2013; 3:252-5. [PMID: 23905007 PMCID: PMC3722611 DOI: 10.1016/j.fob.2013.06.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 06/05/2013] [Accepted: 06/06/2013] [Indexed: 11/20/2022] Open
Abstract
The introduction of non-natural amino acids at the N-terminus of peptides/proteins using leucyl/phenylalanyl-tRNA-protein transferase (L/F-transferase) is a useful technique for protein engineering. To accelerate the chemoenzymatic reaction, here we systematically optimized the N-terminal penultimate residue of the acceptor peptide. Positively charged, small, or hydrophilic amino acids at this position show positive effects for the reaction. Kinetic analysis of peptides possessing different penultimate residues suggests that the side chain of the residue affects peptide-binding affinity towards the L/F-transferase. These findings also provide biological insight into the effect of the penultimate amino acid on substrate specificity of natural proteins to be degraded via the N-end rule pathway. A systematic kinetic analysis of L/F-transferase with different acceptor peptides. L/F-transferase discriminates the N-terminal penultimate residue of substrate peptides. The side chain of this residue affects the peptide binding affinity for L/F-transferase. Ser or Arg is this position optimizes introduction of non-natural amino acids into peptides The N-terminal penultimate residue of a protein may affect its stability in vivo.
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Perioral movements and sucking pattern during bottle feeding with a novel, experimental teat are similar to breastfeeding. J Perinatol 2013; 33:319-23. [PMID: 22975983 DOI: 10.1038/jp.2012.113] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To measure intraoral pressure and perioral movement in infants during breastfeeding (BF) and feeding with experimental teat (ET). The teat has a wide base, firm shaft and a valve at the base, such that milk flows only when the baby provides a hold pressure. STUDY DESIGN Twenty healthy term infants, between 1 and 8 months old, were enrolled in the study. Feeding sessions (BF and ET) were recorded using a digital video camera. During both BF and ET feeding sessions, recordings during feeding were taken of jaw and throat movements (n=20) as well as intraoral pressure (n=18). The efficiency of milk transfer and the angle of the mouth were also measured. RESULT There was no significant difference in either the jaw or throat movements between BF and ET. The sucking burst pattern, the efficiency (ml min(-1)), and the angle of the mouth did not differ between both feeding methods. The intraoral negative pressure observed during ET was significantly smaller than that observed during BF. CONCLUSION There were no significant differences in perioral movements. Although the value was smaller, a hold pressure was observed during ET. From these results, the novel, ET may decrease BF problems related to bottle use.
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High-performance hybrid Raman/fiber Bragg grating fiber-optic sensor based on simplex cyclic pulse coding. OPTICS LETTERS 2013; 38:471-473. [PMID: 23455106 DOI: 10.1364/ol.38.000471] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We propose and experimentally demonstrate the use of cyclic pulse coding to improve the performance of hybrid Raman/fiber Bragg grating (FBG) fiber-optic sensors, for simultaneous measurement of distributed static temperature and discrete dynamic strain over the same sensing fiber. Effective noise reduction is achieved in both Raman optical time-domain reflectometry and dynamic interrogation of time-division-multiplexed fiber FBG sensors, enhancing the sensing range resolution and providing real-time point dynamic strain measurement capabilities. The highly integrated sensor scheme employs broadband apodized low-reflectivity FBGs, a single narrowband optical source, and a shared receiver block.
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Premedication with peppermint oil capsules in colonoscopy: a double blind placebo-controlled randomized trial study. Acta Gastroenterol Belg 2012; 75:349-353. [PMID: 23082707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
BACKGROUND Colonic spasm is an important problem in colonoscopy for endoscopists to advance the colonoscope and visualize the mucosa. STUDY AIMS In the present study, we evaluated the efficacy of enteric-coated peppermint oil capsules (Colpermin) as an orally administered antispasmodic premedication in colonoscopy. PATIENTS AND METHODS Sixty-five adult patients undergoing colonoscopy were randomized to receive either Colpermin (n = 33) or placebo capsules (n = 32) as premedication, 4 hours before the procedure. An experienced endoscopist performed colonoscopy. Outcome measures included cecal intubation and total procedure time, spasm score, pain score, endoscopist satisfaction and patients' willingness to repeat colonoscopy. RESULTS Duration of both total procedure time and cecal intubation time in patients in the Colpermin group were shorter than that in ones in the placebo group. Scores for colonic spasm and pain were significantly lower in the Colpermin group. The endoscopist satisfaction score was higher in the Colpermin group and patients in the Colpermin group were more willing to repeat colonoscopy in the future. CONCLUSIONS Premedication with Colpermin was beneficial in terms of the time required for cecal intubation and total procedure time, reducing colonic spasm, increasing endoscopist satisfaction and decreasing pain in patients during colonoscopy.
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Modulational instability in a passive fiber cavity, revisited. OPTICS LETTERS 2011; 36:4623-4625. [PMID: 22139263 DOI: 10.1364/ol.36.004623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Modulation instability in a passive fiber cavity is revisited. We address the problem in the statement with a continuous-time Ikeda map, rather than in the mean-field limit. It is found that plane wave solutions are unstable for both normal and anomalous dispersion regimes of an optical fiber. The origin of the instability in the continuous-time Ikeda map is in the mode mixing introduced by the beam splitter. The obtained conditions for the instability were compared with ones known for the discrete-time Ikeda map, showing appreciable difference, which, however reduces in the mean-field limit.
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Generation of cnoidal waves by a laser system with a controllable saturable absorber. OPTICS EXPRESS 2011; 19:14210-14216. [PMID: 21934784 DOI: 10.1364/oe.19.014210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We demonstrate the cnoidal wave formation in a two-laser system with a saturable absorber in the cavity of one of the lasers. Another laser is used to activate the saturable absorber in order to control the pulse shape, width, intensity and frequency. Using the three-level laser model based on the Statz--De Mars equations, we show that for any value of the saturable absorber parameter there exists a certain modulation frequency for which the pulse shape is very close to a soliton shape with less than 5% error at the pulse base. Such a device may be prominent for optical communication and laser engineering applications.
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Estimation of RF energy absorbed in the brain from mobile phones in the Interphone Study. Occup Environ Med 2011; 68:686-93. [PMID: 21659468 PMCID: PMC3158331 DOI: 10.1136/oemed-2011-100065] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Objectives The objective of this study was to develop an estimate of a radio frequency (RF) dose as the amount of mobile phone RF energy absorbed at the location of a brain tumour, for use in the Interphone Epidemiological Study. Methods We systematically evaluated and quantified all the main parameters thought to influence the amount of specific RF energy absorbed in the brain from mobile telephone use. For this, we identified the likely important determinants of RF specific energy absorption rate during protocol and questionnaire design, we collected information from study subjects, network operators and laboratories involved in specific energy absorption rate measurements and we studied potential modifiers of phone output through the use of software-modified phones. Data collected were analysed to assess the relative importance of the different factors, leading to the development of an algorithm to evaluate the total cumulative specific RF energy (in joules per kilogram), or dose, absorbed at a particular location in the brain. This algorithm was applied to Interphone Study subjects in five countries. Results The main determinants of total cumulative specific RF energy from mobile phones were communication system and frequency band, location in the brain and amount and duration of mobile phone use. Though there was substantial agreement between categorisation of subjects by cumulative specific RF energy and cumulative call time, misclassification was non-negligible, particularly at higher frequency bands. Factors such as adaptive power control (except in Code Division Multiple Access networks), discontinuous transmission and conditions of phone use were found to have a relatively minor influence on total cumulative specific RF energy. Conclusions While amount and duration of use are important determinants of RF dose in the brain, their impact can be substantially modified by communication system, frequency band and location in the brain. It is important to take these into account in analyses of risk of brain tumours from RF exposure from mobile phones.
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Symmetry-breaking dynamics of the modulational instability spectrum. OPTICS LETTERS 2011; 36:1359-1361. [PMID: 21499356 DOI: 10.1364/ol.36.001359] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We demonstrate in an optical fiber that third-order dispersion yields an unexpected symmetry-breaking dynamics of the modulational instability spectrum. It is found in particular that this spectral asymmetry does not smoothly and monotonically increase when approaching the zero-dispersion wavelength. Instead, it exhibits several local extrema and it can even be reversed at a particular dispersion value. We interpret this behavior as resulting from interactions between dispersive waves and solitons generated from modulation instability.
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Factor VII Deficiency due to Compound Heterozygosity for Leu-48Pro Mutation and a Novel Pro260Leu Mutation. Clin Appl Thromb Hemost 2011; 17:E205-10. [DOI: 10.1177/1076029610397182] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We investigated the mechanisms responsible for factor VII (FVII) deficiency in a compound heterozygous Japanese patient with mutations both in the signal peptide and in the catalytic domain. FVII activity (FVII:C) and antigen (FVII:Ag) levels of the patient were 14.5% and 12.5% of those of the normal controls, respectively. In all, 2 heterozygous point mutations were identified in the patient: one was the mutation substituting Pro for Leu-48 in the prepeptide domain of FVII; the other one was a novel mutation substituting Leu for Pro260 in the catalytic domain. FVII activity and FVII:Ag levels in the condition medium that transiently coexpressed the 2 different FVII mutants in baby hamster kidney (BHK) cells were 4.81% and 5.18% of the wild-type FVII. Factor VII defect of the patient may be combined with both impairing endoplasmic reticulum (ER) targeting and altering FVII folding/biosynthesis, but cotransfection of 2 different FVII mutants may interfere with their expression in BHK cells.
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Fission yeast Ubr1 ubiquitin ligase influences the oxidative stress response via degradation of active Pap1 bZIP transcription factor in the nucleus. Mol Microbiol 2011; 80:739-55. [PMID: 21410566 DOI: 10.1111/j.1365-2958.2011.07605.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cells adapt to oxidative stress by transcriptional activation of genes encoding antioxidants and proteins of other protective roles. A bZIP transcription factor, Pap1, plays a critical role in this process and overexpression of Pap1 confers resistance to various oxidants and drugs in fission yeast. Pap1 temporarily enters the nucleus upon oxidative stress but returns to the cytoplasm once cells adapt to the stress, suggesting that cellular localization regulates Pap1 function. We report here an additional regulatory mechanism that Ubr1 ubiquitin ligase-dependent degradation lowered the Pap1 protein levels. ubr1 cells were causally resistant to hydrogen peroxide because of the increment of Pap1 levels. Pap1 was preferentially degraded in the nucleus where Ubr1 was consistently enriched. Proteolysis was critical to downregulate Pap1 especially when its activation persisted, as constitutively nuclear Pap1 severely inhibited growth in ubr1 mutants. Inactive mutations in the bZIP DNA binding domain stabilized Pap1 but rescued the lethality caused by constitutively active Pap1 in ubr1 mutants. These findings indicate that either nuclear export or Ubr1-mediated proteolysis must be operative to prevent uncontrolled Pap1 function. Coincidental dysfunction in both inhibitory pathways causes lethality because of prolonged activation of Pap1. Ubr1 is a critical regulator for the homeostasis of oxidative stress response.
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Synthesis of a cyclic peptide/protein using the NEXT-A reaction followed by cyclization. Chem Commun (Camb) 2011; 47:9116-8. [DOI: 10.1039/c1cc12196k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Nonlinear supratransmission in multicomponent systems. PHYSICAL REVIEW LETTERS 2010; 105:074101. [PMID: 20868047 DOI: 10.1103/physrevlett.105.074101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2010] [Indexed: 05/29/2023]
Abstract
A method is proposed to solve the challenging problem of determining the supratransmission threshold (onset of instability of harmonic boundary driving inside a band gap) in multicomponent nonintegrable nonlinear systems. It is successfully applied to the degenerate three-wave resonant interaction in a birefringent quadratic medium where the process generates spatial gap solitons. No analytic expression is known for this model showing the broad applicability of the method to nonlinear systems.
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Introduction of a Highly Photodurable and Common-laser Excitable Fluorescent Amino Acid into a Peptide as a FRET Acceptor for Protease Cleavage Detection. CHEM LETT 2010. [DOI: 10.1246/cl.2010.818] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Abstract
L/F-transferase is known to catalyze transfer of hydrophobic amino acids from aminoacyl tRNA to the N-terminus of a protein possessing lysine or arginine as the N-terminus. Combining L/F-transferase with E. coli phenylalanyl-tRNA synthetase (ARS), we achieved non-ribosomal N-terminal-specific introduction of various kinds of nonnatural amino acids to a protein. A nonnatural amino acid is once charged onto an E. coli tRNA(Phe) by a mutant ARS in situ, and successively transferred from the tRNA to a target protein, namely the NEXT-A reaction. Besides alphaA294G mutation on the ARS, alphaT251A, betaG318W, or betaA356W double-mutation were effective to increase the introduction efficiency through the NEXT-A reaction. Protein specific fluorescence labelling via the NEXT-A reaction followed by Huisgen cycloaddition was also demonstrated.
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Impact of the third-order dispersion on the modulation instability gain of pulsed signals. OPTICS LETTERS 2010; 35:1194-1196. [PMID: 20410964 DOI: 10.1364/ol.35.001194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We demonstrate that modulation instability gain of time-localized signals (i.e., pulsed signals) depends strongly on the third-order dispersion, contrary to the well-known case of time-extended signals (cw signals). This surprising contribution of an odd dispersion term on this four-photon-mixing process is established analytically and confirmed by numerical simulations.
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N-terminal specific point-immobilization of active proteins by the one-pot NEXT-A method. Chembiochem 2010; 10:2460-4. [PMID: 19739192 DOI: 10.1002/cbic.200900430] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Abstract
AIM To obtain a better understanding of the changes in feeding behaviour from 1 to 6 months of age. By comparing breast- and bottle-feeding, we intended to clarify the difference in longitudinal sucking performance. METHODS Sucking variables were consecutively measured for 16 breast-fed and eight bottle-fed infants at 1, 3 and 6 months of age. RESULTS For breast-feeding, number of sucks per burst (17.8 +/- 8.8, 23.8 +/- 8.3 and 32.4 +/- 15.3 times), sucking burst duration (11.2 +/- 6.1, 14.7 +/- 8.0 and 17.9 +/- 8.8 sec) and number of sucking bursts per feed (33.9 +/- 13.9, 28.0 +/- 18.2 and 18.6 +/- 12.8 times) at 1, 3 and 6 months of age respectively showed significant differences between 1 and 6 months of age (p < 0.05). The sucking pressure and total number of sucks per feed did not differ among different ages. Bottle-feeding resulted in longer sucking bursts and more sucks per burst compared with breast-feeding in each month (p < 0.05). CONCLUSION The increase in the amount of ingested milk with maturation resulted from an increase in bolus volume per minute as well as the higher number of sucks continuously for both breast- and bottle-fed infants.
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Dissipative optical Bloch waves. OPTICS LETTERS 2009; 34:3388-3390. [PMID: 19881603 DOI: 10.1364/ol.34.003388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We show that nonlinear optical cavities under periodic modulations can exhibit dissipative Bloch waves. This can be achieved by a proper choice of the incident field in the cavity that must both compensate for losses and match with the modulation period. Dissipative Bloch waves, unlike their conservative counterparts, spontaneously emerge in the cavity and hence correspond to attracting solutions. This makes it possible to experimentally visualize the band structure of the cavity medium. As an illustration of this phenomenon, we performed our analytical investigations on a degenerate optical parametric oscillator with a modulated transverse refractive index.
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