Minimal Symptom Expression' in Patients With Acetylcholine Receptor Antibody-Positive Refractory Generalized Myasthenia Gravis Treated With Eculizumab

The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension

Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

Possible influence of the non-classical nature of light on biological systems

It has been shown that laser sight shown in water can convert some of the light into nonclassical photon pairs. Also, photonic counterparts of Cooper pairs have been shown to occur when light scatters off of various media. Here, we consider the effects of non-classical light produced by such interactions on biological systems and whether there could be an influence.3rd QST International Symposium "Quantum Life Science

Possible precision measurements of Delbrück scattering with high flux polarized gamma-ray sources

Quantum electrodynamics (QED), which describes the interaction of photons with electrons, has been tested experimentally and found to agree with experiments to high precision to lowest order. However, higher order measurements are required to test QED. Delbrück scattering is a higher order process, which involves the scattering of photons off the Coulomb fields of nuclei and is the only one which has been measured due to its large cross section. We have found recently that polarized gamma ray sources can achieve high precision measurements of Delbrück scattering. Currently, there are many petawatt-class laser facilities operating, being constructed, and planned around the world. Such laser systems can produce extremely high flux highly polarized gamma rays in laser-plasma, electron beam-laser interactions. Therefore, they have the possibility of measuring Delbrück scattering to high precision. We believe this will be of great interest to the plasma and fusion research community at large.Japan-US Joint Seminar on High Density Scienc

Possiblity for measuring Delbrueck Scattering in the sub-MeV range using polarized gamma-ray photons

Delbrueck scattering is the elastic scattering of gamma-rays off the Coulomb field of nuclei due to the formation of virtual electron-positron pairs from vacuum. The elastic scattering of gamma-ray sources from atoms is a coherent sum of Rayleigh, Thomson, Giant Dipole resonances and Delbrueck scattering and as energies go below the MeV level the Rayleigh scattering becomes more and more dominant. Previous experiments performed using unpolarized gamma-ray sources have shown the effects of Delbrueck scattering at photon energies as low as 889 keV. However, linearly polarized gamma-rays via laser Compton backscattering sources having high flux offer the possibility to measure Delbrueck scattering with a higher degree of accuracy at these and even lower energies. Here, we show that by properly choosing the scattering angles and polarization of the gamma-rays one can measure Delbrueck scattering in the sub-MeV range. By choosing a high Z material we will present the time necessary using the new gamma-ray sources to measure Delbrueck scattering accurately.Light driven Nuclear-Particle physics and Cosmology 201

New Regime of Ultrahigh Laser and High Electron/Positron Interaction

The International Linear Collider (ILC) will have electron and positron beam energies above 125 GeV. High intensity lasers have achieved unprecedented intensities of $10^{23}$ W/cm$^2$. Although typically such lasers have photons with energies in the eV range in the laboratory frame, colliding such high intensity lasers and the ultrahigh energy electron and positron beams of the ILC will result in laser photons with energies comparable the electron rest mass colliding with electrons or positrons at rest in the center-of-mass frame. Having such collisions after the interaction point will provide a unique opportunity to study high field science and applications. We will present simulation results of the interaction using the CAIN code and discuss the fundamental physics possibilities, such as generation of electron-positron cascades and generation of exotic particles, as well as possible applications such as easing the burden on the beam dumps through the reduction of the beam energies with ultrahigh intensity lasers.ILC Workshop on Potential Experiments (ILCX

Possibilities to observe Delbrück scattering at next generation laser facilities

We show by using high-flux linearly polarized laser Compton gamma-ray sources the contribution of the vacuum component, Delbrück scattering, to the elastic scattering of the gamma-rays off nuclei is nearly isolated for photon energies below the electron-positron pair creation threshold. We discuss the possibility of measuring Delbrück scattering at new ultra-high power laser and X-ray Free Electron Laser facilities.59th Annual Meeting of the APS Division of Plasma Physic