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3. Surface and volume effects in the photoabsorption of nuclei

Author

Krusche, B., Lehr, J., Bloch, F., Kotulla, M., Metag, V., Mosel, U., and Schadmand, S.

Subjects
Nuclear Experiment
Abstract

Recent experimental results for meson photoproduction from nuclei obtained with TAPS at MAMI are analyzed in view of the suppression of the second nucleon resonance region in total photoabsorption. The cross sections can be split into a component from the low density surface region of nuclei and a component which scales more like the nuclear volume. The energy dependence of the surface component is similar to the deuteron cross section, it shows a clear signal for the second resonance peak assigned to the excitation of the P11(1440), D13(1520), and S11(1535). The volume component behaves differently, it is lacking the second resonance peak and shows an enhancement at intermediate photon energies., Comment: accepted for publication in Eur. J. Phys. A

Published
2004
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4. Photoproduction of pi0-mesons from nuclei

Author

Krusche, B., Lehr, J., Ahrens, J., Annand, J. R. M., Beck, R., Bloch, F., Fog, L. S., Hornidge, D., Janssen, S., Kotulla, M., McGeorge, J. C., MacGregor, I. J. D., Messchendorp, J., Metag, V., Mosel, U., Novotny, R., Owens, R. O., Pfeiffer, M., Sanderson, R., Schadmand, S., and Watts, D. P.

Subjects
Nuclear Experiment
Abstract

Photoproduction of neutral pions from nuclei (carbon, calcium, niobium, lead) has been studied for incident photon energies from 200 MeV to 800 MeV with the TAPS detector using the Glasgow photon tagging spectrometer at the Mainz MAMI accelerator. Data were obtained for the inclusive photoproduction of neutral pions and the partial channels of quasifree single pi0, double pi0, and pi0pi+/- photoproduction. They have been analyzed in terms of the in-medium behavior of nucleon resonances and the pion - nucleus interaction. They are compared to earlier measurements from the deuteron and to the predictions of a Boltzmann-Uehling-Uhlenbeck (BUU) transport model for photon induced pion production from nuclei., Comment: 15 pages, 22 figures, accepted for publication in EPJ A

Published
2004
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5. In-medium Properties of Hadrons -- Observables

Author

Falter, T., Lehr, J., Mosel, U., Muehlich, P., and Post, M.

Subjects
Nuclear Theory, High Energy Physics - Phenomenology, Nuclear Experiment
Abstract

We first briefly review the theoretical basis for calculations of changes of hadronic properties in dense nuclear matter. These changes have usually been investigated by means of relativistic heavy-ion reactions. Here we discuss that observable consequences of such changes can also be seen in more elementary reactions on nuclei. Particular emphasis is put on a discussion of actual observables in photonuclear reactions; we discuss in detail $\eta$- and vector-meson production. We show that photoproduction of $\eta$'s can yield essential information on in-medium properties of the $S_{11}(1535)$ resonance while the $\phi$ meson properties will probably not be accessible through the $K^+K^-$ decay channel. However, for $\omega$ mesons the $\pi^0\gamma$ decay channel, due to its reduced final state interaction, looks more promising in this respect. Completely free of final state interactions is dilepton production in the few GeV range. We show that the sensitivity of this decay channel to changes of hadronic properties in medium in photonuclear reactions on nuclei is as large as in ultrarelativistic heavy ion collisions. Finally we discuss that hadron production in nuclei at 10 -- 20 GeV photon energies can give important information on the hadronization process., Comment: Invited Lecture by U. Mosel at Erice International School on Nuclear Physics 2003

Published
2003
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6. Influence of the nucleon spectral function in photon and electron induced reactions on nuclei

Author

Lehr, J. and Mosel, U.

Subjects
Nuclear Theory
Abstract

We study the influence of the nucleon spectral function on eta photo- and electroproduction on nuclei. Besides kinematical effects due to groundstate correlations, also a modification of the S11(1535) decay width is taken into account, which is caused by the possible decay into nucleons with mass smaller than the pole mass in the medium. Hence, resonances with masses below the free N eta threshold can contribute to eta production., Comment: 13 pages, 8 figures

Published
2003
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7. Eta electroproduction on nuclei in the nucleon resonance region

Author

Lehr, J. and Mosel, U.

Subjects
Nuclear Theory
Abstract

We investigate eta electroproduction on nuclei for Q^2=2.4 and 3.6 GeV^2 in the framework of a coupled-channel BUU transport model. We analyze the importance of final state interactions and side feeding and compare with findings drawn from eta photoproduction. It is shown that in contrast to photoproduction the influence of etas stemming from secondary processes becomes important at high Q^2., Comment: 5 pages, 5 figures

Published
2003
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8. In-medium modifications of the S11(1535) resonance and eta photoproduction

Author

Lehr, J., Post, M., and Mosel, U.

Subjects
Nuclear Theory
Abstract

We investigate the influence of possible in-medium modifications of the S11(1535) in eta photoproduction in nuclei. Besides Fermi motion, Pauli blocking and binding effects also collisional broadening is accounted for. The in-medium width is obtained from a realistic resonance-hole model. Results on eta photoproduction are obtained from a semi-classical BUU transport model and compared with data. We find that calculations including a momentum dependent nucleon and resonance potential are in agreement with the recent KEK data. In contrast, collisional broadening has only little influence., Comment: 6 pages, 7 figures, minor changes in Fig. 4 and Sect. 3

Published
2003
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9. Photoproduction of phi mesons from nuclei

Author

Muehlich, P., Falter, T., Greiner, C., Lehr, J., Post, M., and Mosel, U.

Subjects
Nuclear Theory
Abstract

We investigate the consequences of possible medium modifications of the phi meson at finite nuclear matter density on the K+K- mass distribution in photonuclear reactions. The inclusive cross sections for K+K- pair production are calculated within a semi--classical BUU transport model, which combines the initial state interaction of the incoming photon with the final state interactions of the produced particles. The effects of final state interactions on the invariant mass distribution of the observed K+K- pairs are discussed in detail. In addition we calculate the Coulomb correction and possible effects of hadronic kaon potentials on the K+K- mass spectrum. Due to the large cross sections for reactions of the final state particles with the surrounding nuclear medium and the influence of the Coulomb potential we find no measurable sensitivity of the observables to the phi properties at finite baryon density., Comment: revtex4, 24 pages

Published
2002
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10. Photon and Electron induced Particle Production on Nuclei

Author

Lehr, J. and Mosel, U.

Subjects
Nuclear Theory
Abstract

We discuss several particle production reactions on nuclei within a BUU transport model. After a short presentation of the model we show our results for the transparency ratio for the nucleon knock-out reaction in different nuclei. The influence of the nucleon spectral function on subthreshold particle production is discussed., Comment: 4 pages, 2 figures, to appear in the proceedings of the Third International Conference on Perspectives in Hadronic Physics, Trieste, Italy, 7-11 May 2001

Published
2001
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11. Nuclear Matter Spectral Functions by Transport Theory

Author

Lehr, J., Lenske, H., Leupold, S., and Mosel, U.

Subjects
Nuclear Theory
Abstract

Quantum transport theory is used to calculate the nucleon spectral function in infinite nuclear matter. A self-consistent description is obtained by utilizing the relations between collision rates and correlation functions. Static and dynamical self-energies are taken into account in the single particle propagators. The real parts of the non-static self-energy contributions are calculated by dispersion theory thus conserving the analyticity of momentum distributions. The transport theoretical spectral functions, momentum distributions, occupation probabilities and responce functions are in close agreement with results of variational and other many-body theoretical calculations. The results indicate that the nucleon spectral functions are determined only by the average short-range correlation strength., Comment: 24 pages, 8 figures, few changes in the text, new figure 3

Published
2001
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12. In-medium broadening of nucleon resonances

Author

Lehr, J. and Mosel, U.

Subjects
Nuclear Theory
Abstract

We analyze the effects of an in-medium broadening of nucleon resonances on the exclusive photoproduction of mesons on nuclei as well as on the total photoabsorption cross sections in a transport calculation. We show that the resonance widths observed in semi-inclusive photoproduction on nuclei are insensitive to an in-medium broadening of nucleon resonances. This is due to a simple effect: the sizeable width of the nuclear surface and Fermi motion., Comment: 4 pages, 3 figures, minor changes in the text

Published
2001
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13. Transport Theoretical Approach to the Nucleon Spectral Function in Nuclear Matter

Author

Lehr, J., Effenberger, M., Lenske, H., Leupold, S., and Mosel, U.

Subjects
Nuclear Theory
Abstract

The nucleon spectral function in infinite nuclear matter is calculated in a quantum transport theoretical approach. Exploiting the known relation between collision rates and correlation functions the spectral function is derived self-consistently. By re-inserting the spectral functions into the collision integrals the description of hard processes from the high-momentum components of wave functions and interactions is improved iteratively until convergence is achieved. The momentum and energy distributions and the nuclear matter occupation probabilities are in very good agreement with the results obtained from many-body theory., Comment: minor changes in the text, additional curves in fig. 2

Published
2000
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14. Electron and Photon induced Reactions on Nuclei in the Nucleon Resonance Region

Author

Lehr, J., Effenberger, M., and Mosel, U.

Subjects
Nuclear Theory
Abstract

We calculate total photon-nucleus and electron-nucleus cross sections $\gamma A\to X$, $e A\to e^\prime X$ and several cross sections on pion and eta production in nuclei in the energy regime between the first and the third resonance region for photon virtualities $Q^2\le 1.0 GeV^2$ within a semi-classical BUU transport model. In both cases we discuss the varying influence of several medium modifications on the cross sections for different values of Q^2., Comment: 43 pages including figures

Published
1999
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16. Mass Wasting Along Atlantic Continental Margins: A Comparison Between NW-Africa and the de la Plata River Region (Northern Argentina and Uruguay)

Author

Krastel, S., Lehr, J., Winkelmann, D., Schwenk, T., Preu, B., Strasser, M., Wynn, R. B., Georgiopoulou, A., Hanebuth, T. J. J., Krastel, Sebastian, editor, Behrmann, Jan-Hinrich, editor, Völker, David, editor, Stipp, Michael, editor, Berndt, Christian, editor, Urgeles, Roger, editor, Chaytor, Jason, editor, Huhn, Katrin, editor, Strasser, Michael, editor, and Harbitz, Carl Bonnevie, editor

Published
2014
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17. The January 2022 Hunga Volcano explosive eruption from the multitechnological perspective of CTBT monitoring.

Author

Donner, S, Steinberg, A, Lehr, J, Pilger, C, Hupe, P, Gaebler, P, Ross, J O, Eibl, E P S, Heimann, S, Rebscher, D, Plenefisch, T, and Ceranna, L

Subjects
VOLCANIC eruptions, COMPREHENSIVE Nuclear-Test-Ban Treaty, EARTHQUAKES, ATMOSPHERIC transport, EXPLOSIVE volcanic eruptions, EARTH sciences, ATMOSPHERIC models
Abstract

The massive eruption of the Hunga Volcano on 15 January 2022 provides an ideal test case for reviewing established methods to discriminate and analyse source processes. Discriminating source mechanisms and identifying their origins is a key task when analysing suspicious events in the frame of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Earthquakes and explosions can be distinguished in some cases using well established methods such as inversion for the seismic moment tensor. In more complex cases the combination of analyses of the seismic, infrasonic and hydroacoustic waveform content can be of help. More challenging is the discrimination of the specific kind of explosive source such as a nuclear test and a volcano eruption based on the data from the three waveform technologies alone. Here, we apply standard techniques destined to analyse relevant events in the frame of the CTBT, that is all three waveform technologies (seismology, infrasound and hydroacoustic) and atmospheric transport modelling of radionuclides. We investigate the potential of standard analysis methods to discriminate a source and identify their possible weaknesses. We show that the methods applied here work very well to identify, investigate and discriminate an explosive event. During discrimination we could not only exclude a shear-source (i.e. earthquake) but also distinguish the volcanic explosion in contrast to a man-made explosion. However, some tasks remain difficult with the available methods. These tasks include the reliable estimation of the strength of a non-shear event and thereupon a yield estimation of a possibly CTBT relevant event. In addition to evaluating our methods, we could relate our results with specific phases of the eruption process providing a more detailed insight of what happened. Our investigations of the eruption details only provide a starting point for further in-depth analysis. However, they underline the importance of the Hunga eruption event for science. The huge amount of observations provide a unique opportunity for knowledge gain in several subdisciplines of the geosciences. In addition, although not being a nuclear test, it also provides a useful and important data set for further developing multitechnology analyses in the frame of the CTBT. [ABSTRACT FROM AUTHOR]

Published
2023
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18. Surface Reconstruction of Maltese Cisterns Using ROV Sonar Data for Archeological Study

Author

Forney, C., Forrester, J., Bagley, B., McVicker, W., White, J., Smith, T., Batryn, J., Gonzalez, A., Lehr, J., Gambin, T., Clark, C. M., Wood, Z. J., Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Bebis, George, editor, Boyle, Richard, editor, Parvin, Bahram, editor, Koracin, Darko, editor, Wang, Song, editor, Kyungnam, Kim, editor, Benes, Bedrich, editor, Moreland, Kenneth, editor, Borst, Christoph, editor, DiVerdi, Stephen, editor, Yi-Jen, Chiang, editor, and Ming, Jiang, editor

Published
2011
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31. Subnanosecond corona inception in an ultrawideband environment

Author

Mankowski, John, Dickens, Jim, Kristiansen, M., Lehr, J., Prather, W., and Gaudet, J.

Subjects
Broadband amplifiers, Business, Chemistry, Electronics, Electronics and electrical industries
Abstract

Corona discharges in ultrawideband radiating systems can have adverse effects on performance such as reflection, phase dispersion, and significant power losses. A test-bed has been assembled to experimentally observe corona created by voltage pulses similar to ultrawideband systems. The current work involves the attenuation of an incident pulse after propagation through a self-initiated corona and relative measurements of visible light emission from the photoionization produced during streamer development. Several gas dielectrics, including ambient air, [N.sub.2], [H.sub.2], and S[F.sub.6], were tested.

Published
2002

33. Image restoration in X-ray microscopy: PSF determination and biological applications

Author

Lehr, J., Sibarita, J.-B., and Chassery, J.-M.

Subjects
Image coding -- Methods, Image processing -- Methods, Business, Computers, Electronics, Electronics and electrical industries
Abstract

Research has established an digital image restoration technique in X-ray microscopy which employs point spread function. Improvements in image quality are achieved through the presence of low signal-to-noise ratio and reduced image degradation. The image enhancement technique can be applied to various methodologies in biology such as chromosome imaging.

Published
1998

45. Effect of Oral Insulin on Prevention of Diabetes in Relatives of Patients With Type 1 Diabetes A Randomized Clinical Trial

Author

Greenbaum, C., Atkinson, M., Baidal, D., Battaglia, M., Bingley, P., Bosi, E., Buckner, J., Clements, M., Colman, P., DiMeglio, L., Evans-Molina, C., Gitelman, S., Goland, R., Gottlieb, P., Herold, K., Knip, M., Krischer, J., Lernmark, A., Moore, W., Moran, A., Muir, A., Palmer, J., Peakman, M., Philipson, L., Raskin, P., Redondo, M., Rodriguez, H., Russell, W., Spain, L., Schatz, D.A., Sosenko, J., Wherrett, D., Wilson, D., Winter, W., Ziegler, A., Anderson, M., Antinozzi, P., Benoist, C., Blum, J., Bourcier, K., Chase, P., Clare-Salzler, M., Clynes, R., Cowie, C., Eisenbarth, G., Fathman, C.G., Grave, G., Harrison, L., Hering, B., Insel, R., Jordan, S., Kaufman, F., Kay, T., Kenyon, N., Klines, R., Lachin, J., Leschek, E., Mahon, J., Marks, J.B., Monzavi, R., Nanto-Salonen, K., Nepom, G., Orban, T., Parkman, R., Pescovitz, M., Peyman, J., Pugliese, A., Ridge, J., Roep, B., Roncarolo, M., Savage, P., Simell, O., Sherwin, R., Siegelman, M., Skyler, J.S., Thomas, J., Trucco, M., Wagner, J., Greenbaum, C.J., Krischer, J.P., Rafkin, L., Foulkes, M., Krause-Steinrauf, H., Lachin, J.M., Malozowski, S., Zafonte, S.J., Kenyon, N.S., Santiago, I., Bundy, B., Abbondondolo, M., Adams, T., Asif, D.A.I., Boonstra, M., Boulware, D., Burroughs, C., Cuthbertson, D., Eberhard, C., Fiske, S., Ford, J., Garmeson, J., Guillette, H., Geyer, S., Hays, B., Henderson, C., Henry, M., Heyman, K., Hsiao, B., Karges, C., Kinderman, A., Lane, L., Leinbach, A., Liu, S., Lloyd, J., Malloy, J., Maddox, K., Martin, J., Miller, J., Moore, M., Muller, S., Nguyen, T., O'Donnell, R., Parker, M., Pereyra, M.J., Reed, N., Roberts, A., Sadler, K., Stavros, T., Tamura, R., Wood, K., Xu, P., Young, K., Alies, P., Badias, F., Baker, A., Bassi, M., Beam, C., Bounmananh, L., Bream, S., Deemer, M., Freeman, D., Gough, J., Ginem, J., Granger, M., Holloway, M., Kieffer, M., Lane, P., Law, P., Linton, C., Nallamshetty, L., Oduah, V., Parrimon, Y., Paulus, K., Pilger, J., Ramiro, J., Ritzie, A.Q.L., Sharma, A., Shor, A., Song, X.H., Terry, A., Weinberger, J., Wootten, M., Harding, M.F.P., McDonough, S., Mcgee, P.F., Hess, K.O., Phoebus, D., Quinlan, S., Raiden, E., Fradkin, J., Beck, G., Blumberg, E., Gubitosi-Klug, R., Laffel, L., Veatch, R., Wallace, D., Braun, J., Brillon, D., B. lo, Mitchell, H., Naji, A., Nerup, J., Orchard, T., Steffes, M., Tsiatis, A., Zinman, B., Loechelt, B., Baden, L., Green, M., Weinberg, A., Marcovina, S., Palmer, J.P., Yu, L.P., Shultz, A., Batts, E., Fitzpatrick, K., Ramey, M., Guerra, R., Webb, C., Caffey, F., Carr, L., Ergun-Longmire, B., Fenton, C., Giebner, D., Johnson, J., Maglionico, D., Marinelli, M., Martin, K., Minnozzi, E., Riley, W., Wilson, M., Gougeon, C., Ho, J., Huang, C., Pacaud, D., Virtanen, H., Craig, C., Ghatak, A., Henderson, T., Leyland, H., Padmore, K., Paul, P., Brickman, W., Halsey-Lyda, M., Petrie, P., Rizzo, D., Steuer, R., Suchyta, K., Torchen, L., Zimmerman, D., Bode, B., Dial, M., Gazaway, K., Hosey, R., Alkanani, A., Barker, J., Barr, M., Blau, A., Burdick, P., Burke, B., Chase, H., Drye, M., Escobar, E., Fitzgerald-Miller, L., Fouts, A., Gage, V., Gall, E., Goettle, H., Harris, S., Ketchum, K., King, M., Klingensmith, G., Lehr, D., Lehr, J., Lewis, L., Logsden-Sackett, N., Lykens, J., Maahs, D., Michels, A., Pelletier, S., Rihanek, M., Rodriguez, P., Schauwecker, A., Simmons, K., Smith, J., Steck, A., Tran, B., Tran, T., Wadwa, P., Wagner, R., Wright, H., Betancourt, J., Bui, V., DeSalvo, D., Gomez, D., Jake, K., Lynds, J., McCartney, T., McDonald, A., Pena, S., Pietropaolo, M., Greenbaum, C., Atkinson, M., Baidal, D., Battaglia, M., Becker, D., Bingley, P., Bosi, E., Buckner, J., Clements, M., Colman, P., Dimeglio, L., Evans-Molina, C., Gitelman, S., Goland, R., Gottlieb, P., Herold, K., Knip, M., Krischer, J., Lernmark, A., Moore, W., Moran, A., Muir, A., Palmer, J., Peakman, M., Philipson, L., Raskin, P., Redondo, M., Rodriguez, H., Russell, W., Spain, L., Schatz, D. A., Sosenko, J., Wherrett, D., Wilson, D., Winter, W., and Ziegler, A.

Subjects
0301 basic medicine, Male, medicine.medical_specialty, Adolescent, medicine.medical_treatment, Administration, Oral, 030209 endocrinology & metabolism, Placebo, law.invention, 03 medical and health sciences, 0302 clinical medicine, Randomized controlled trial, Interquartile range, law, Internal medicine, Diabetes mellitus, medicine, Humans, Hypoglycemic Agents, Insulin, Family, Treatment Failure, Child, Original Investigation, Autoantibodies, Type 1 diabetes, Glucose tolerance test, medicine.diagnostic_test, business.industry, General Medicine, ta3121, Glucose Tolerance Test, medicine.disease, 030104 developmental biology, Diabetes Mellitus, Type 1, Child, Preschool, Cohort, Female, business, Follow-Up Studies
Abstract

Importance Type 1 diabetes requires major lifestyle changes and carries increased morbidity and mortality. Prevention or delay of diabetes would have major clinical effect. Objective To determine whether oral insulin delays onset of type 1 diabetes in autoantibody-positive relatives of patients with type 1 diabetes. Design, Setting, and Participants Between March 2, 2007, and December 21, 2015, relatives with at least 2 autoantibodies, including insulin autoantibodies and normal glucose tolerance, were enrolled in Canada, the United States, Australia, New Zealand, the United Kingdom, Italy, Sweden, Finland, and Germany. The main study group (n = 389) had first-phase insulin release on an intravenous glucose tolerance test that was higher than the threshold. The 55 patients in the secondary stratum 1 had an identical antibody profile as the main study group except they had first-phase insulin release that was lower than the threshold. Secondary strata 2 (n = 114) and strata 3 (n = 3) had different autoantibody profiles and first-phase insulin release threshold combinations. Follow-up continued through December 31, 2016. Interventions Randomization to receive 7.5 mg/d of oral insulin (n = 283) or placebo (n = 277), including participants in the main study group who received oral insulin (n = 203) or placebo (n = 186). Main Outcome and Measures The primary outcome was time to diabetes in the main study group. Significance was based on a 1-sided threshold of .05, and 1-sided 95% CIs are reported. Results Of a total of 560 randomized participants (median enrollment age, 8.2 years; interquartile range [IQR], 5.7-12.1 years; 170 boys [60%]; 90.7% white non-Hispanic; 57.6% with a sibling with type 1 diabetes), 550 completed the trial including 389 participants (median age, 8.4 years; 245 boys [63%]), 382 (96%) in the main study group. During a median follow-up of 2.7 years (IQR, 1.5-4.6 years) in the main study group, diabetes was diagnosed in 58 participants (28.5%) in the oral insulin group and 62 (33%) in the placebo group. Time to diabetes was not significantly different between the 2 groups (hazard ratio [HR], 0.87; 95% CI, 0-1.2;P = .21). In secondary stratum 1 (n = 55), diabetes was diagnosed in 13 participants (48.1%) in the oral insulin group and in 19 participants (70.3%) in the placebo group. The time to diabetes was significantly longer with oral insulin (HR, 0.45; 95% CI, 0-0.82;P = .006). The HR for time to diabetes for the between-group comparisons for the 116 participants in the other secondary stratum was 1.03 (95% CI, 0-2.11;P = .53) and for the entire cohort of 560 participants was 0.83 (95% CI, 0-1.07;P = .11), which were not significantly different. The most common adverse event was infection (n = 254), with 134 events in the oral insulin group and 120 events in the placebo group, but no significant study-related adverse events occurred. Conclusions and Relevance Among autoantibody-positive relatives of patients with type 1 diabetes, oral insulin at a dose of 7.5 mg/d, compared with placebo, did not delay or prevent the development of type 1 diabetes over 2.7 years. These findings do not support oral insulin as used in this study for diabetes prevention. Trial Registration clinicaltrials.gov Identifier:NCT00419562

Published
2017

46. Pro-inflammatory activation of primary microglia and macrophages increases 18kDa Translocator Protein (TSPO) expression in rodents but not humans

Author

Owen, DRJ, Narayan, N, Wells, L, Healy, L, Smyth, E, Rabiner, EA, Galloway, D, Williams, JB, Lehr, J, Mandhir, H, Peferoen, LAN, Taylor, PC, Amor, S, Antel, JP, Matthews, PM, Moore, CS, and Medical Research Council (MRC)

Subjects
Adult, Lipopolysaccharides, Positron emission tomography, Pyridines, microglia, Gene Expression, 1102 Cardiovascular Medicine And Haematology, Endocrinology & Metabolism, Interferon-gamma, Young Adult, POSITRON-EMISSION-TOMOGRAPHY, Receptors, GABA, Species Specificity, Acetamides, Animals, Humans, PERIPHERAL BENZODIAZEPINE-RECEPTOR, Myeloid Cells, BRAIN, IN-VIVO, Cells, Cultured, Science & Technology, Neurology & Neurosurgery, Macrophages, HUMAN ADULT MICROGLIA, Neurosciences, neurodegeneration, Granulocyte-Macrophage Colony-Stimulating Factor, 1103 Clinical Sciences, Hematology, MULTIPLE-SCLEROSIS, MOUSE MODEL, Middle Aged, ALZHEIMERS-DISEASE, Mice, Inbred C57BL, PET, inflammation, Neurosciences & Neurology, 1109 Neurosciences, Life Sciences & Biomedicine, TSPO, Protein Binding
Abstract

The 18kDa Translocator Protein (TSPO) is the most commonly used tissue-specific marker of inflammation in positron emission tomography (PET) studies. It is expressed in myeloid cells such as microglia and macrophages, and in rodent myeloid cells expression increases with cellular activation. We assessed the effect of myeloid cell activation on TSPO gene expression in both primary human and rodent microglia and macrophages in vitro, and also measured TSPO radioligand binding with 3H-PBR28 in primary human macrophages. As observed previously, we found that TSPO expression increases (∼9-fold) in rodent-derived macrophages and microglia upon pro-inflammatory stimulation. However, TSPO expression does not increase with classical pro-inflammatory activation in primary human microglia (fold change 0.85 [95% CI 0.58–1.12], p = 0.47). In contrast, pro-inflammatory activation of human monocyte-derived macrophages is associated with a reduction of both TSPO gene expression (fold change 0.60 [95% CI 0.45–0.74], p = 0.02) and TSPO binding site abundance (fold change 0.61 [95% CI 0.49–0.73], p

Published
2017

47. Basic Research Needs for Materials Under Extreme Environments. Report of the Basic Energy Sciences Workshop on Materials Under Extreme Environments, June 11-13, 2007

Author

Wadsworth, J., primary, Crabtree, G. W., additional, Hemley, R. J., additional, Falcone, R., additional, Robertson, I., additional, Stringer, J., additional, Tortorelli, P., additional, Gray, G. T., additional, Nicol, M., additional, Lehr, J., additional, Tozer, S. W., additional, Diaz de la Rubia, T., additional, Fitzsimmons, T., additional, Vetrano, J. S., additional, Ashton, C. L., additional, Kitts, S., additional, Landson, C., additional, Campbell, B., additional, Gruzalski, G., additional, and Stevens, D., additional

Published
2008
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49. Dexamethasone intravitreal implant in previously treated patients with diabetic macular edema: Subgroup analysis of the MEAD study

Author

Augustin, A. J., Kuppermann, B. D., Lanzetta, P., Loewenstein, A., X. -Y., Li, Cui, H., Hashad, Y., Whitcup, S. M., Abujamra, S., Acton, J., Ali, F., Antoszyk, A., Awh, C. C., Barak, A., Bartz-Schmidt, K. U., Baumal, C. R., Belfort, R. Jr., Bhende, M., Boyer, D. S., Bridges, W. Z. Jr., Brown, D. M., Carmichael, T., Carnevale, K., Casella, A. M., Chang, T., Chechik, D., Chen, S. -N., Chong, L. P., Chong, V., Corwin, J., Creuzot-Garcher, C., Cruess, A., Daniell, M., De Avila, M. P., De Moraes, H. V. Jr., Devenyi, R. G., Doft, B. H., Donaldson, M., Dreyer, R., Eliott, D., Engel, H. M., Ernest, J., Essman, T. F., Falcone, P. M., Fekrat, S., Ferencz, J. R., Ferreira, J. L., Figueira, J., Fiser, I., Foster, B., Fox, G. M., Freeman, W. R., Garg, S. P., Gillies, M., Glaser, D., Goldstein, B. G., Gomes, A. M. V., Gonder, J. R., Gopal, L., Gous, P., Gupta, A., Halperin, L., Han, D., Hariprasad, S. M., Holz, F. G., Kaiser, P., Kalvodova, B., Katz, B., Katz, R. S., Kecik, D., Kellaway, J., Klemperer, I., Lattanzio, R., Lee, W. -K., Lehr, J., Leys, M., Loose, I., Lotery, A., D. -W., Lu, Mccartney, P., Majji, A. B., Martinez, J. A., Massin, P., Maturi, R. K., Menchini, U., Menon, G., Michels, M., Midena, E., Miller, J. Jr., Mitchell, P., Moisseiev, J., Morse, L., Navarro, R., Nemeth, J., Newland, H., Newsom, R., Nichols, J., Orellana, J., Orzalesi, N., Paranhos, A. Jr., Park, R., Park, S., Parodi, M. B., Pavan, P. R., Peace, J., Perez-Ortiz, D. J., Pollack, A., Ramaswamy, K., Ratnakaram, R., Ravalico, G., Rehak, J., Rezaei, K., Rizzo, S., Rodriguez-Alvira, F. J., Romanet, J. -P., Rose, S., Rosen, R. B., Rossetti, L., Ruiz-Moreno, J. M., Sadda, S., Sall, K., Sandner, D., Sanz, A. F. -V., Sartani, G., Schmickler, S., Schwartz, S. D., Sharma, Y. R., Sheu, S. -J., Singer, M., Sivaprasad, S., Soubrane, G., Soucek, P., Souied, E. H., Staurenghi, G., Studnicka, J., Suarez-Figueroa, M., Takahashi, W. Y., Tognetto, D., Tsai, P. L., Ulanski, L. J., H. S., Uy, Varano, M., Veith, M., Vicha, I., Viola, F., Visser, L., Weinberger, D., Wing, G. L., Wong, E., Wong, T. Y., Wylegala, E., Yan, J., Yoon, Y. H., Young, L. H., H. G., Yu, Zimmer-Galler, I. E., Augustin, Aj, Kuppermann, Bd, Lanzetta, P, Loewenstein, A, Li, Xy, Cui, H, Hashad, Y, Whitcup, Sm, on behalf of for the Ozurdex MEAD Study, Group, Battaglia Parodi, M, Augustin, A. J., Kuppermann, B. D., Lanzetta, P., Loewenstein, A., Li, X. -Y., Cui, H., Hashad, Y., Whitcup, S. M., Abujamra, S., Acton, J., Ali, F., Antoszyk, A., Awh, C. C., Barak, A., Bartz-Schmidt, K. U., Baumal, C. R., Belfort, R., Bhende, M., Boyer, D. S., Bridges, W. Z., Brown, D. M., Carmichael, T., Carnevale, K., Casella, A. M., Chang, T., Chechik, D., Chen, S. -N., Chong, L. P., Chong, V., Corwin, J., Creuzot-Garcher, C., Cruess, A., Daniell, M., De Avila, M. P., De Moraes, H. V., Devenyi, R. G., Doft, B. H., Donaldson, M., Dreyer, R., Eliott, D., Engel, H. M., Ernest, J., Essman, T. F., Falcone, P. M., Fekrat, S., Ferencz, J. R., Ferreira, J. L., Figueira, J., Fiser, I., Foster, B., Fox, G. M., Freeman, W. R., Garg, S. P., Gillies, M., Glaser, D., Goldstein, B. G., Gomes, A. M. V., Gonder, J. R., Gopal, L., Gous, P., Gupta, A., Halperin, L., Han, D., Hariprasad, S. M., Holz, F. G., Kaiser, P., Kalvodova, B., Katz, B., Katz, R. S., Kecik, D., Kellaway, J., Klemperer, I., Lattanzio, R., Lee, W. -K., Lehr, J., Leys, M., Loose, I., Lotery, A., Lu, D. -W., Mccartney, P., Majji, A. B., Martinez, J. A., Massin, P., Maturi, R. K., Menchini, U., Menon, G., Michels, M., Midena, E., Miller, J., Mitchell, P., Moisseiev, J., Morse, L., Navarro, R., Nemeth, J., Newland, H., Newsom, R., Nichols, J., Orellana, J., Orzalesi, N., Paranhos, A., Park, R., Park, S., Parodi, M. B., Pavan, P. R., Peace, J., Perez-Ortiz, D. J., Pollack, A., Ramaswamy, K., Ratnakaram, R., Ravalico, G., Rehak, J., Rezaei, K., Rizzo, S., Rodriguez-Alvira, F. J., Romanet, J. -P., Rose, S., Rosen, R. B., Rossetti, L., Ruiz-Moreno, J. M., Sadda, S., Sall, K., Sandner, D., Sanz, A. F. -V., Sartani, G., Schmickler, S., Schwartz, S. D., Sharma, Y. R., Sheu, S. -J., Singer, M., Sivaprasad, S., Soubrane, G., Soucek, P., Souied, E. H., Staurenghi, G., Studnicka, J., Suarez-Figueroa, M., Takahashi, W. Y., Tognetto, D., Tsai, P. L., Ulanski, L. J., Uy, H. S., Varano, M., Veith, M., Vicha, I., Viola, F., Visser, L., Weinberger, D., Wing, G. L., Wong, E., Wong, T. Y., Wylegala, E., Yan, J., Yoon, Y. H., Young, L. H., Yu, H. G., and Zimmer-Galler, I. E.

Subjects
Male, Vascular Endothelial Growth Factor A, Visual acuity, Triamcinolone acetonide, genetic structures, medicine.medical_treatment, Visual Acuity, Angiogenesis Inhibitors, Drug Implant, Triamcinolone Acetonide, Dexamethasone, Immunosuppressive Agent, Glucocorticoid, Diabetic retinopathy, Dexamethasone Intravitreal Implant, Corticosteroid, Drug delivery, Implant, Macular edema, Aged, Diabetic Retinopathy, Drug Implants, Female, Glucocorticoids, Humans, Immunosuppressive Agents, Intravitreal Injections, Macular Edema, Middle Aged, Retreatment, Tomography, Optical Coherence, Ophthalmology, Tomography, General Medicine, medicine.symptom, medicine.drug, Angiogenesis Inhibitor, Human, Research Article, medicine.medical_specialty, Subgroup analysis, medicine, business.industry, Intravitreal Injection, Cataract surgery, medicine.disease, eye diseases, Optical Coherence, business
Abstract

Dexamethasone intravitreal implant 0.7 mg (DEX 0.7) was approved for treatment of diabetic macular edema (DME) after demonstration of its efficacy and safety in the MEAD registration trials. We performed subgroup analysis of MEAD study results to evaluate the efficacy and safety of DEX 0.7 treatment in patients with previously treated DME. Three-year, randomized, sham-controlled phase 3 study in patients with DME, best-corrected visual acuity (BCVA) of 34–68 Early Treatment Diabetic Retinopathy Study letters (20/200–20/50 Snellen equivalent), and central retinal thickness (CRT) ≥300 μm measured by time-domain optical coherence tomography. Patients were randomized to 1 of 2 doses of DEX (0.7 mg or 0.35 mg), or to sham procedure, with retreatment no more than every 6 months. The primary endpoint was ≥15-letter gain in BCVA at study end. Average change in BCVA and CRT from baseline during the study (area-under-the-curve approach) and adverse events were also evaluated. The present subgroup analysis evaluated outcomes in patients randomized to DEX 0.7 (marketed dose) or sham based on prior treatment for DME at study entry. Baseline characteristics of previously treated DEX 0.7 (n = 247) and sham (n = 261) patients were similar. In the previously treated subgroup, mean number of treatments over 3 years was 4.1 for DEX 0.7 and 3.2 for sham, 21.5 % of DEX 0.7 patients versus 11.1 % of sham had ≥15-letter BCVA gain from baseline at study end (P = 0.002), mean average BCVA change from baseline was +3.2 letters with DEX 0.7 versus +1.5 letters with sham (P = 0.024), and mean average CRT change from baseline was −126.1 μm with DEX 0.7 versus −39.0 μm with sham (P

Published
2015

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