616 research outputs found
Volumetric optoacoustic neurobehavioral tracking of epileptic seizures in freely-swimming zebrafish larvae
Fast three-dimensional imaging of freely-swimming zebrafish is essential to understand the link between neuronal activity and behavioral changes during epileptic seizures. Studying the complex spatiotemporal patterns of neuronal activity at the whole-brain or -body level typically requires physical restraint, thus hindering the observation of unperturbed behavior. Here we report on real-time volumetric optoacoustic imaging of aberrant circular swimming activity and calcium transients in freely behaving zebrafish larvae, continuously covering their motion across an entire three-dimensional region. The high spatiotemporal resolution of the technique enables capturing ictal-like epileptic seizure events and quantifying their propagation speed, independently validated with simultaneous widefield fluorescence recordings. The work sets the stage for discerning functional interconnections between zebrafish behavior and neuronal activity for studying fundamental mechanisms of epilepsy and in vivo validation of treatment strategies
Antitumour necrosis factor-α therapy for hidradenitis suppurativa: results from a national cohort study between 2000 and 2013
International audienceHidradenitis suppurativa (HS) is a frequent chronic inflammatory skin disease typically characterized by recurrent painful, deep inflammatory nodules of the axillary, breast, groin and gluteal areas. European recommendations are mainly based on expert opinion. Drug treatments are heterogenous (e.g., antibiotics, corticosteroids, retinoids) and lack consensus among expert centres. The most severe disease forms or those failing to respond to conventional drugs may be associated with worsened functional prognosis. Anti-tumor necrosis factor α (anti-TNFα) drugs have been prescribed in these cases. The results of randomized controlled trials (RCTs) are discordant. Three RCTs concluded to the efficacy of adalimumab (ADA), and two others did not detect any difference between infliximab (IFX) or etanercept (ETA) and placebo. Finally, data from the literature and reported experiences do not conclude on the efficacy of anti-TNFα drugs for HS. This article is protected by copyright. All rights reserve
Reflective multi-immersion microscope objectives inspired by the Schmidt telescope
Imaging large, cleared samples requires microscope objectives that combine a large field of view (FOV) with a long working distance (WD) and a high numerical aperture (NA). Ideally, such objectives should be compatible with a wide range of immersion media, which is challenging to achieve with conventional lens-based objective designs. Here we introduce the multi-immersion 'Schmidt objective' consisting of a spherical mirror and an aspherical correction plate as a solution to this problem. We demonstrate that a multi-photon variant of the Schmidt objective is compatible with all homogeneous immersion media and achieves an NA of 1.08 at a refractive index of 1.56, 1.1-mm FOV and 11-mm WD. We highlight its versatility by imaging cleared samples in various media ranging from air and water to benzyl alcohol/benzyl benzoate, dibenzyl ether and ethyl cinnamate and by imaging of neuronal activity in larval zebrafish in vivo. In principle, the concept can be extended to any imaging modality, including wide-field, confocal and light-sheet microscopy
Elevated photic response is followed by a rapid decay and depressed state in ictogenic networks
Objective: The switch between nonseizure and seizure states involves profound alterations in network excitability and synchrony. In this study, we aimed to identify and compare features of neural excitability and dynamics across multiple zebrafish seizure and epilepsy models.
Methods: Inspired by video-electroencephalographic recordings in patients, we developed a framework to study spontaneous and photically evoked neural and locomotor activity in zebrafish larvae, by combining high-throughput behavioral tracking and whole-brain in vivo two-photon calcium imaging.
Results: Our setup allowed us to dissect behavioral and physiological features that are divergent or convergent across multiple models. We observed that spontaneous locomotor and neural activity exhibit great diversity across models. Nonetheless, during photic stimulation, hyperexcitability and rapid response dynamics were well conserved across multiple models, highlighting the reliability of photically evoked activity for high-throughput assays. Intriguingly, in several models, we observed that the initial elevated photic response is often followed by rapid decay of neural activity and a prominent depressed state. Elevated photic response and following depressed state in seizure-prone networks are significantly reduced by the antiseizure medication valproic acid. Finally, rapid decay and depression of neural activity following photic stimulation temporally overlap with slow recruitment of astroglial calcium signals that are enhanced in seizure-prone networks.
Significance: We argue that fast decay of neural activity and depressed states following photic response are likely due to homeostatic mechanisms triggered by excessive neural activity. An improved understanding of the interplay between elevated and depressed excitability states might suggest tailored epilepsy therapies.
Keywords: astroglia; calcium imaging; depressed state; elevated state; epilepsy; high-throughput behavior; hyperexcitability; photic stimulation; seizure; zebrafis
Economic crisis and the construction of a neo-liberal regulatory regime in Korea
A consistent theme of the literature on the ontology of the 1997 South Korean crisis is the key role played by regulatory failures and the growing weakness of the state. This paper seeks to briefly highlight both the insights and the limitations of this approach to understanding the crisis. Having done so, we shall set out the argument that the crisis created an opportunity for reformist Korean Ă©lites to advance their longstanding, but previously frustrated, project to create a comprehensive unambiguously neo-liberal regulatory regime. This paper will also seek to highlight the implications of our reading of the development of the Korean political economy for broader debates on economic liberalisation, crisis and the future of the developmental state
Designing the stripe-ordered cuprate phase diagram through uniaxial-stress
The ability to efficiently control charge and spin in the cuprate
high-temperature superconductors is crucial for fundamental research and
underpins technological development. Here, we explore the tunability of
magnetism, superconductivity and crystal structure in the stripe phase of the
cuprate La_2-xBa_xCuO_4, with x = 0.115 and 0.135, by employing
temperature-dependent (down to 400 mK) muon-spin rotation and AC
susceptibility, as well as X-ray scattering experiments under compressive
uniaxial stress in the CuO_2 plane. A sixfold increase of the 3-dimensional
(3D) superconducting critical temperature T_c and a full recovery of the 3D
phase coherence is observed in both samples with the application of extremely
low uniaxial stress of 0.1 GPa. This finding demonstrates the removal of the
well-known 1/8-anomaly of cuprates by uniaxial stress. On the other hand, the
spin-stripe order temperature as well as the magnetic fraction at 400 mK show
only a modest decrease under stress. Moreover, the onset temperatures of 3D
superconductivity and spin-stripe order are very similar in the large stress
regime. However, a substantial decrease of the magnetic volume fraction and a
full suppression of the low-temperature tetragonal structure is found at
elevated temperatures, which is a necessary condition for the development of
the 3D superconducting phase with optimal T_c. Our results evidence a
remarkable cooperation between the long-range static spin-stripe order and the
underlying crystalline order with the three-dimensional fully coherent
superconductivity. Overall, these results suggest that the stripe- and the SC
order may have a common physical mechanism.Comment: 11 pages, 5 figures. This work builds on our earlier findings on
LBCO, arXiv:2008.01159, and substantially expands i
Catålogo de cultivares de café aråbica.
Esta publicação tem por objetivo disponibilizar e sistematizar, de forma sucinta, as principais caracterĂsticas agronĂŽmicas e tecnolĂłgicas de cultivares de cafĂ© arĂĄbica, a fim de auxiliar os produtores dos CafĂ©s do Brasil na escolha do material genĂ©tico que melhor atenda Ă s suas necessidades tĂ©cnicas e econĂŽmicas. SĂŁo destacadas as principais caracterĂsticas de 90 cultivares de Coffea arabica, as quais foram fruto do trabalho colaborativo de programas de pesquisa de instituiçÔes fundadoras e parceiras do ConsĂłrcio Brasileiro de Pesquisa e Desenvolvimento do CafĂ©, rede integrada de pesquisa constituĂda em 1997, formada por mais de 40 instituiçÔes de ensino, pesquisa e extensĂŁo rural, coordenada pela Embrapa CafĂ©
Dosing and Monitoring of Trace Elements in LongâTerm Home Parenteral Nutrition Patients
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141314/1/jpen0736.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141314/2/jpen0736-sup-0001.pd
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