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1.
Opt Express ; 32(8): 14735-14745, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38859410

RESUMEN

The creation and manipulation of coherence continues to capture the attention of scientists and engineers. The optical laser is a canonical example of a system that, in principle, exhibits complete coherence. Recent research has focused on the creation of coherent, laser-like states in other physical systems. The phonon laser is one example where it is possible to amplify self-sustained mechanical oscillations. A single mode phonon laser in a levitated optical tweezer has been demonstrated through appropriate balance of active feedback gain and damping. In this work, coherent control of the dynamics of an optical tweezer phonon laser is used to share coherence between its different modes of oscillation, creating a multimode phonon laser. The coupling of the modes is achieved by periodically rotating the asymmetric optical potential in the transverse focal plane of the trapping beam via trap laser polarization rotation. The presented theory and experiment demonstrate that coherence can be transferred across different modes of an optical tweezer phonon laser, and are a step toward using these systems for precision measurement and quantum information processing.

2.
Phys Rev Lett ; 132(24): 241801, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38949335

RESUMEN

We present a first search for dark-trident scattering in a neutrino beam using a dataset corresponding to 7.2×10^{20} protons on target taken with the MicroBooNE detector at Fermilab. Proton interactions in the neutrino target at the main injector produce π^{0} and η mesons, which could decay into dark-matter (DM) particles mediated via a dark photon A^{'}. A convolutional neural network is trained to identify interactions of the DM particles in the liquid-argon time projection chamber (LArTPC) exploiting its imagelike reconstruction capability. In the absence of a DM signal, we provide limits at the 90% confidence level on the squared kinematic mixing parameter ϵ^{2} as a function of the dark-photon mass in the range 10≤M_{A^{'}}≤400 MeV. The limits cover previously unconstrained parameter space for the production of fermion or scalar DM particles χ for two benchmark models with mass ratios M_{χ}/M_{A^{'}}=0.6 and 2 and for dark fine-structure constants 0.1≤α_{D}≤1.

3.
Phys Rev Lett ; 132(15): 151801, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38683006

RESUMEN

We present a measurement of η production from neutrino interactions on argon with the MicroBooNE detector. The modeling of resonant neutrino interactions on argon is a critical aspect of the neutrino oscillation physics program being carried out by the DUNE and Short Baseline Neutrino programs. η production in neutrino interactions provides a powerful new probe of resonant interactions, complementary to pion channels, and is particularly suited to the study of higher-order resonances beyond the Δ(1232). We measure a flux-integrated cross section for neutrino-induced η production on argon of 3.22±0.84(stat)±0.86(syst) 10^{-41} cm^{2}/nucleon. By demonstrating the successful reconstruction of the two photons resulting from η production, this analysis enables a novel calibration technique for electromagnetic showers in GeV accelerator neutrino experiments.

4.
Phys Rev Lett ; 132(4): 041801, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38335355

RESUMEN

We present the first search for heavy neutral leptons (HNLs) decaying into νe^{+}e^{-} or νπ^{0} final states in a liquid-argon time projection chamber using data collected with the MicroBooNE detector. The data were recorded synchronously with the NuMI neutrino beam from Fermilab's main injector corresponding to a total exposure of 7.01×10^{20} protons on target. We set upper limits at the 90% confidence level on the mixing parameter |U_{µ4}|^{2} in the mass ranges 10≤m_{HNL}≤150 MeV for the νe^{+}e^{-} channel and 150≤m_{HNL}≤245 MeV for the νπ^{0} channel, assuming |U_{e4}|^{2}=|U_{τ4}|^{2}=0. These limits represent the most stringent constraints in the mass range 35

5.
Phys Rev Lett ; 130(1): 011801, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36669216

RESUMEN

We present a search for eV-scale sterile neutrino oscillations in the MicroBooNE liquid argon detector, simultaneously considering all possible appearance and disappearance effects within the 3+1 active-to-sterile neutrino oscillation framework. We analyze the neutrino candidate events for the recent measurements of charged-current ν_{e} and ν_{µ} interactions in the MicroBooNE detector, using data corresponding to an exposure of 6.37×10^{20} protons on target from the Fermilab booster neutrino beam. We observe no evidence of light sterile neutrino oscillations and derive exclusion contours at the 95% confidence level in the plane of the mass-squared splitting Δm_{41}^{2} and the sterile neutrino mixing angles θ_{µe} and θ_{ee}, excluding part of the parameter space allowed by experimental anomalies. Cancellation of ν_{e} appearance and ν_{e} disappearance effects due to the full 3+1 treatment of the analysis leads to a degeneracy when determining the oscillation parameters, which is discussed in this Letter and will be addressed by future analyses.

6.
Phys Rev Lett ; 131(10): 101802, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37739352

RESUMEN

We report the first measurement of flux-integrated double-differential quasielasticlike neutrino-argon cross sections, which have been made using the Booster Neutrino Beam and the MicroBooNE detector at Fermi National Accelerator Laboratory. The data are presented as a function of kinematic imbalance variables which are sensitive to nuclear ground-state distributions and hadronic reinteraction processes. We find that the measured cross sections in different phase-space regions are sensitive to different nuclear effects. Therefore, they enable the impact of specific nuclear effects on the neutrino-nucleus interaction to be isolated more completely than was possible using previous single-differential cross section measurements. Our results provide precision data to help test and improve neutrino-nucleus interaction models. They further support ongoing neutrino-oscillation studies by establishing phase-space regions where precise reaction modeling has already been achieved.

7.
Phys Rev Lett ; 131(16): 161802, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37925710

RESUMEN

We present a new measurement of the positive muon magnetic anomaly, a_{µ}≡(g_{µ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{µ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{µ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{µ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision.

8.
Phys Rev Lett ; 130(23): 231802, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37354393

RESUMEN

We present the first measurement of the cross section of Cabibbo-suppressed Λ baryon production, using data collected with the MicroBooNE detector when exposed to the neutrinos from the main injector beam at the Fermi National Accelerator Laboratory. The data analyzed correspond to 2.2×10^{20} protons on target running in neutrino mode, and 4.9×10^{20} protons on target running in anti-neutrino mode. An automated selection is combined with hand scanning, with the former identifying five candidate Λ production events when the signal was unblinded, consistent with the GENIE prediction of 5.3±1.1 events. Several scanners were employed, selecting between three and five events, compared with a prediction from a blinded Monte Carlo simulation study of 3.7±1.0 events. Restricting the phase space to only include Λ baryons that decay above MicroBooNE's detection thresholds, we obtain a flux averaged cross section of 2.0_{-1.7}^{+2.2}×10^{-40} cm^{2}/Ar, where statistical and systematic uncertainties are combined.


Asunto(s)
Mesones , Protones , Simulación por Computador , Método de Montecarlo
9.
Reprod Biomed Online ; 47(1): 84-93, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37149412

RESUMEN

RESEARCH QUESTION: Can low-dose letrozole reduce dysmenorrhoea, menorrhagia and sonographic features in symptomatic women with adenomyosis awaiting IVF? DESIGN: This was a longitudinal randomized prospective pilot study to explore the effectiveness of low-dose letrozole and compare it with a gonadotropin releasing hormone (GnRH) agonist in reducing dysmenorrhoea, menorrhagia and sonographic features in symptomatic women with adenomyosis awaiting IVF. The women were treated for 3 months, either with the GnRH agonist goserelin 3.6 mg/month (n = 77) or the aromatase inhibitor letrozole 2.5 mg three times weekly (n = 79). Dysmenorrhoea and menorrhagia were evaluated at randomization and followed up monthly using a visual analogue score (VAS) and pictorial blood loss assessment chart (PBAC), respectively. A quantitative scoring method was used to assess the improvement of sonographic features after 3 months of treatment. RESULTS: Both groups reported a marked improvement in symptoms after 3 months of treatment. In both the letrozole and GnRH agonist groups, VAS and PBAC scores decreased significantly over the 3 months (letrozole: P = 0.0001 and P = 0.0001 for VAS and PBAC, respectively; GnRH agonist: P = 0.0001 and P = 0.0001 for VAS and PBAC, respectively). Participants on letrozole had regular menstruation cycles, while most of the women who received the GnRH agonist were amenorrhoeic, with only four women reporting mild bleeding. Haemoglobin concentrations also improved after both treatments (letrozole P = 0.0001, GnRH agonist P = 0.0001). A quantitative assessment of sonographic features showed significant improvements following both treatments (diffuse adenomyosis of the myometrium: letrozole P = 0.015, GnRH agonist P = 0.039; diffuse adenomyosis of the junctional zone: letrozole P = 0.025, GnRH agonist P = 0.001). Women with adenomyoma also responded well to both therapies (letrozole P = 0.049, GnRH agonist P = 0.024), whereas the letrozole group responded comparatively better in focal adenomyosis when the outer myometrium was involved (letrozole P < 0.001, GnRH agonist P = 0.26). No noticeable side effects were observed in women receiving letrozole therapy. Additionally, letrozole therapy was found to be more cost-effective than GnRH agonist treatment. CONCLUSIONS: Low-dose letrozole treatment is a low-cost alternative to a GnRH agonist, with comparable effects in improving the symptoms and sonographic features of adenomyosis in women awaiting IVF.


Asunto(s)
Adenomiosis , Menorragia , Femenino , Humanos , Letrozol/uso terapéutico , Adenomiosis/complicaciones , Adenomiosis/tratamiento farmacológico , Proyectos Piloto , Dismenorrea , Menorragia/tratamiento farmacológico , Hormona Liberadora de Gonadotropina , Estudios Prospectivos , Fertilización In Vitro/métodos
10.
Phys Rev Lett ; 127(11): 113601, 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34558916

RESUMEN

This theoretical work initiates contact between two frontier disciplines of physics, namely, atomic superfluid rotation and cavity optomechanics. It considers an annular Bose-Einstein condensate, which exhibits dissipationless flow and is a paradigm of rotational quantum physics, inside a cavity excited by optical fields carrying orbital angular momentum. It provides the first platform that can sense ring Bose-Einstein condensate rotation with minimal destruction, in situ and in real time, unlike demonstrated techniques, all of which involve fully destructive measurement. It also shows how light can actively manipulate rotating matter waves by optomechanically entangling persistent currents. Our work opens up a novel and useful direction in the sensing and manipulation of atomic superflow.

11.
Phys Rev Lett ; 126(14): 141801, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33891447

RESUMEN

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{µ}≡(g_{µ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{µ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both µ^{+} and µ^{-}, the new experimental average of a_{µ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

12.
Arch Microbiol ; 204(1): 33, 2021 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-34923604

RESUMEN

Soil microbial diversity consisted of both culturable and non-culturable microbes. The cultivated microbes can be identified by conventional microbiological processes. However, that is not possible for the non-culturable ones. In those cases, next-generation sequencing (NGS)-based metagenomics become useful. In this study, we targeted two very popular tea gardens of Darjeeling hills-Makaibari (Mak) and Castleton (Cas). The main difference between these two study areas is the type of manure they use. Mak is solely an organic tea garden using all organic manure and fertilizers whereas Cas uses inorganic pesticides and fertilizers. The main aim was to compare the effect of organic manure over chemical fertilizers on the soil microbiomes. We have performed the 16 s metagenomics analysis based on the V3-V4 region. Downstream bioinformatics analysis including reverse ecology was performed. We found that the overall microbial diversity is higher in Mak compared to Cas. Moreover, the use of organic manure has reduced the population of pathogenic bacteria in Mak soil when compared to Cas soil. From the observations made through the metagenomics analysis of Mak and Cas soil samples, we may conclude that the application of organic manure supports the population of good bacteria in the soil which may eventually impact the tea garden workers' health.


Asunto(s)
Estiércol , Metagenómica , Humanos , India , Suelo ,
13.
Opt Express ; 28(3): 4234-4248, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32122080

RESUMEN

We present theoretical and experimental investigations of higher order correlations of mechanical motion in the recently demonstrated optical tweezer phonon laser, consisting of a silica nanosphere trapped in vacuum by a tightly focused optical beam [R. M. Pettit et al., Nature Photonics 13, 402 (2019)]. The nanoparticle phonon number probability distribution is modeled with the master equation formalism in order to study its evolution across the lasing threshold. Up to fourth-order equal-time correlation functions are then derived from the probability distribution. Subsequently, the master equation is transformed into a nonlinear quantum Langevin equation for the trapped particle's position. This equation yields the non-equal-time correlations, also up to fourth order. Finally, we present experimental measurements of the phononic correlation functions, which are in good agreement with our theoretical predictions. We also compare the experimental data to existing analytical Ginzburg-Landau theory where we find only a partial match.

14.
World J Microbiol Biotechnol ; 35(10): 148, 2019 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-31549233

RESUMEN

Assessment of temperature effect on plant resistance against diseases has become essential under climate change scenario as temperature rise is anticipated to modify host resistance. To determine temperature influence on resistance gene, a pair of near-isogenic rice lines differing for the Pi54 resistance gene was assessed against leaf blast. Blast resistance was determined as the extent of infection efficiency (IE) and sporulation (SP) at suboptimal (22 °C and 32 °C) and optimal temperature (27 °C) of pathogen aggressiveness. Relative resistance for IE and SP was higher at suboptimal temperature as compared to that of optimal temperature. Maximum level of resistance was at 22 °C where higher levels of expression of Pi54 and defence-regulatory transcription factor WRKY45 were also noted. At 32 °C, although some level of resistance noted, but level of Pi54 and WRKY45 expression was too low, suggesting that resistance recorded at higher temperature was due to reduced pathogen aggressiveness. At the optimal temperature for pathogen aggressiveness, comparatively lower levels of Pi54 and WRKY45 expression suggest possible temperature-induced interruption of the defence processes. The variation in resistance patterns modulated by temperature is appeared to be due to pathogen's sensitivity to temperature that leads to varying levels of Pi54 gene activation. Quick and violent activity of the pathogen at optimal temperature came into sight for the interruption of defence process activated by Pi54 gene. Evaluation of blast resistance genes under variable temperature conditions together with weather data could be applied in screening rice genotypes for selection of resistance having resilience to temperature rise.


Asunto(s)
Oryza/genética , Oryza/inmunología , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/inmunología , Plantas Modificadas Genéticamente/inmunología , Magnaporthe/fisiología , Oryza/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Hojas de la Planta/genética , Hojas de la Planta/inmunología , Hojas de la Planta/microbiología , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/microbiología , Temperatura
15.
Opt Express ; 25(16): 19568-19582, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-29041150

RESUMEN

We analyze magnetometry using an optically levitated nanodiamond. We consider a configuration where a magnetic field gradient couples the mechanical oscillation of the diamond with its spin degree of freedom provided by a nitrogen vacancy center. First, we investigate the measurement of the position spectrum of the mechanical oscillator. We find that conditions of ultrahigh vacuum and feedback cooling allow a magnetic field gradient sensitivity of 1µTm-1/Hz. At high pressure and room temperature, this sensitivity degrades and can attain a value of the order of 100mTm-1/Hz. Subsequently, we characterize the magnetic field gradient sensitivity obtainable by maneuvering the spin degrees of freedom using Ramsey interferometry. We find that this technique can offer photon-shot noise and spin-projection noise limited magnetic field gradient sensitivity of 100µTm-1/Hz. We conclude that this hybrid levitated nanomechanical magnetometer provides a favorable and versatile platform for sensing applications.

16.
Haemophilia ; 22(4): 570-82, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27291889

RESUMEN

INTRODUCTION: Inherited macrothrombocytopenia represents a heterogeneous group of disorders which are characterized by the presence of a reduced number of abnormally large platelets in the circulation, which may or may not be associated with a bleeding tendency. In spite of several causative genes having been identified, the underlying genetic defects remain to be identified in approximately half of the cases. AIMS: To understand the molecular pathology of isolated giant platelet disorder from India. MATERIALS AND METHODS: We studied 112 cases that were referred for investigation of macrothrombocytopenia. Agonist induced platelet aggregation and platelet GP1b/IX/V receptor expression were investigated to assess GP1b/IX/V receptor expression and the GP1BA, GP1BB, GP9, ABCG5, ABCG8, TUBB1 and MYH9 genes were analysed to identify candidate gene defects. RESULTS: Twenty-three candidate gene defects were identified in 48 of 112 cases, 20 of which were novel. Of the candidate defects identified, 91% were missense and 9% were nonsense variations. The missense variations were in GP9 (9), ABCG5 (4), GP1BB (3), GP1BA (3) and MYH9 (2), while the nonsense defects occurred in MYH9 (1) and GP1BA (1). CONCLUSIONS: This study increases the understanding of the molecular basis of an isolated giant platelet disorder, a common heterogeneous condition prevalent in north and eastern India.


Asunto(s)
Enfermedades Genéticas Ligadas al Cromosoma X/diagnóstico , Complejo GPIb-IX de Glicoproteína Plaquetaria/metabolismo , Trombocitopenia/diagnóstico , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 5/genética , Adolescente , Adulto , Anciano , Pruebas de Coagulación Sanguínea , Plaquetas/citología , Plaquetas/metabolismo , Niño , Codón sin Sentido , Femenino , Estudios de Asociación Genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Genotipo , Hemorragia/etiología , Heterocigoto , Humanos , India , Lipoproteínas/genética , Masculino , Persona de Mediana Edad , Proteínas Motoras Moleculares/genética , Mutación Missense , Cadenas Pesadas de Miosina/genética , Fenotipo , Complejo GPIb-IX de Glicoproteína Plaquetaria/genética , Polimorfismo de Nucleótido Simple , Trombocitopenia/congénito , Trombocitopenia/genética , Adulto Joven
17.
J Microsc ; 258(3): 253-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25787717

RESUMEN

We report a simple method for measuring the inelastic mean free path of nanostructures of known geometry using energy filtered transmission electron microscopy imaging. The mean free path of inelastic electrons was measured by using systems having known symmetry, such as cylindrical or cubic, combined with Poisson statistics without employing the knowledge of microscope parameters, namely the convergence angle and the collection angle. Having inherent symmetry of such systems, their absolute thickness can be measured from their two-dimensional projection images. We have calculated mean free path of inelastic scattering of electrons in gold, silver and nickel doing case study research by employing gold nanorod, silver nanocube and nickel nanorod lying on a carbon-coated TEM grid at two different electron energies (viz. 200 and 300 keV) following this alternative approach. Results obtained using such alternative approach were verified using microscope parameters.

18.
Biomed Microdevices ; 16(1): 69-78, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24122322

RESUMEN

The use of bottom-up approaches in tissue engineering applications is advantageous since they enable the combination of various layers that could be made from different materials and/or incorporate different biochemical cues. Regarding the complex structure and the vascular system of the bone tissue, the aim of this study was to develop an innovative bottom-up approach that allows the construction of 3D biodegradable scaffolds from 2D microfabricated membranes with precise shape, pore size and porosity. For that purpose, poly (caprolactone) (PCL) and starch ­ poly (caprolactone) (SPCL (30 % starch)) blended sheets were used as substrates to produce the microfabricated membranes using micro hotembossing. The use of this micro fabrication process allowed accurately imprinting micropillars and microholes in reproducible way. The assembling of the microfabricated membranes was performed using an easy, highly reproducible and inexpensive approach based on its successive stacking. Additionaly, the suitability of the microfabricated membranes to support the attachment and the cytoskeletal organization of human bone marrow stem cells (hBMSCs), macrovascular endothelial cells and osteoblasts derived from hBMSCs was demonstrated. Furthermore, hBMSCs proliferated and maintained the expression of the stromal progenitor marker STRO-1 when cultured on both PCL and SPCL microfabricated membranes. The proposed methodology constitutes a promising alternative to the traditional processing methods used to prepare tissue engineering scaffolds.


Asunto(s)
Huesos/química , Microtecnología/métodos , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Adhesión Celular , Diferenciación Celular , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana , Humanos , Inmunohistoquímica , Células Madre Mesenquimatosas/química , Microscopía Electrónica de Rastreo , Osteoblastos/química , Polímeros/química , Porosidad
19.
J Opt Soc Am A Opt Image Sci Vis ; 30(12): 2526-30, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-24323013

RESUMEN

We present a ray transfer matrix for a spiral phase plate. Using this matrix we determine the stability of an optical resonator made of two spiral phase plates and trace stable ray orbits in the resonator. Our results should be relevant to laser physics, optical micromanipulation, quantum information, and optomechanics.

20.
Am J Physiol Lung Cell Mol Physiol ; 303(1): L12-9, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22561460

RESUMEN

We recently reported that integrin α(v)ß(3) is necessary for vascular barrier protection in mouse models of acute lung injury and peritonitis. Here, we used mass spectrometric sequencing of integrin complexes to isolate the novel ß(3)-integrin binding partner IQGAP1. Like integrin ß(3), IQGAP1 localized to the endothelial cell-cell junction after sphingosine-1-phosphate (S1P) treatment, and IQGAP1 knockdown prevented cortical actin formation and barrier enhancement in response to S1P. Furthermore, knockdown of IQGAP1 prevented localization of integrin α(v)ß(3) to the cell-cell junction. Similar to ß(3)-null animals, IQGAP1-null mice had increased pulmonary vascular leak compared with wild-type controls 3 days after intratracheal LPS. In an Escherichia coli pneumonia model, IQGAP1 knockout mice had increased lung weights, lung water, and lung extravascular plasma equivalents of (125)I-labeled albumin compared with wild-type controls. Taken together, these experiments indicate that IQGAP1 is necessary for S1P-mediated vascular barrier protection during acute lung injury and is required for junctional localization of the barrier-protective integrin α(v)ß(3).


Asunto(s)
Lesión Pulmonar Aguda/metabolismo , Lesión Pulmonar Aguda/patología , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Neumonía/metabolismo , Neumonía/patología , Proteínas Activadoras de ras GTPasa/metabolismo , Actinas/metabolismo , Lesión Pulmonar Aguda/genética , Animales , Células Cultivadas , Células Endoteliales/metabolismo , Células Endoteliales/patología , Integrina alfaVbeta3/metabolismo , Lipopolisacáridos/farmacología , Pulmón/metabolismo , Pulmón/patología , Lisofosfolípidos/metabolismo , Ratones , Ratones Noqueados , Neumonía/genética , Unión Proteica/fisiología , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Proteínas Activadoras de ras GTPasa/genética
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