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1. Possible background reductions in double beta decay experiments

Author

Arnold, R., Augier, C., Baker, J., Barabash, A., Bing, O., Brudanin, V., Caffrey, A. J., Caurier, E., Errahmane, K., Etienvre, A. -I., Guyonnet, J. L., Hubert, F., Hubert, Ph., Jollet, C., Jullian, S., Kochetov, O., Kovalenko, V., Lalanne, D., Leccia, F., Longuemare, C., Marquet, Ch., Mauger, F., Nicholson, H. W., Ohsumi, H., Piquemal, F., Reyss, J-L., Sarazin, X., Shitov, Yu., Simard, L., Stekl, I., Suhonen, J., Sutton, C. S., Szklarz, G., Timkin, V., Tretyak, V., Umatov, V., Vala, L., Vanyushin, I., Vasilyev, V., Vorobel, V., and Vylov, Ts.

Subjects
Nuclear Experiment
Abstract

The background induced by radioactive impurities of $^{208}\rm Tl$ and $^{214}\rm Bi$ in the source of the double beta experiment NEMO-3 has been investigated. New methods of data analysis which decrease the background from the above mentioned contamination are identified. The techniques can also be applied to other double beta decay experiments capable of measuring independently the energies of the two electrons., Comment: 15 pages, 13 figures, accepted in the Nuclear Instruments and Methods A

Published
2003
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2. Near-threshold eta production in the p d -> p d eta reaction

Author

Hibou, F., Wilkin, C., Bergdolt, A. M., Bergdolt, G., Bing, O., Boivin, M., Bouchakour, A., Brochard, F., Combes-Comets, M. P., Courtat, P., Gacougnolle, R., Bornec, Y. Le, Moalem, A., Plouin, F., Reide, F., Tatischeff, B., and Willis, N.

Subjects
Nuclear Experiment
Abstract

The total cross section of the p d -> p d eta reaction has been measured at two energies near threshold by detecting the final proton and deuteron in a magneti spectrometer. The values are somewhat larger than expected on the basis of two simple theoretical estimates., Comment: 13 pages, LaTeX, 4 eps figures

Published
2000
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3. Near-Threshold Production of omega Mesons in the pp -> pp omega Reaction

Author

Hibou, F., Bing, O., Boivin, M., Courtat, P., Gacougnolle, R., Bornec, Y. Le, Martin, J. M., Plouin, F., Tatischeff, B., Wilkin, C., Willis, N., and Wurzinger, R.

Subjects
Nuclear Experiment
Abstract

The total cross section for omega production in the pp -> pp omega reaction has been measured at five c.m. excess energies from 3.8 to 30 MeV. The energy dependence is easily understood in terms of a strong proton-proton final state interaction combined with a smearing over the width of the state. The ratio of near-threshold phi and omega production is consistent with the predictions of a one-pion-exchange model and the degree of violation of the OZI rule is similar to that found in the pi-p -> n omega/phi reactions., Comment: Report in LaTeX2e. 12 pages with 2 eps figures

Published
1999
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4. Study of the ABC Enhancement in the d d -> alpha X reaction

Author

Wurzinger, R., Bing, O., Boivin, M., Courtat, P., Faldt, G., Gacougnolle, R., Gardestig, A., Hibou, F., Bornec, Y. Le, Martin, J. M., Plouin, F., Tatischeff, B., Wilkin, C., Willis, N., Yonnet, J., and Zghiche, A.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The polarized d d -> alpha X reaction at beam energies close to the eta threshold shows very strong structure in the missing mass corresponding to the ABC enhancement. The deuteron tensor analysing power A_yy, and the slope of the vector analysing power A_y with respect to angle, have been measured for this reaction around the forward direction. Both signals are small, and their variations with the alpha-particle momentum are in broad agreement with a theoretical model in which each pair of nucleons in the projectile and target deuterons undergoes pion production through the NN -> d pi reaction., Comment: LaTeX2e, 10 pages, 3 eps figures, submitted to Physics Letters B

Published
1998
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5. Comparison of eta and eta' production in the pp -> pp eta(eta') reactions near threshold

Author

Hibou, F., Bing, O., Boivin, M., Courtat, P., Faldt, G., Gacougnolle, R., Bornec, Y. Le, Martin, J. M., Moalem, A., Plouin, F., Taleb, A., Tatischeff, B., Wilkin, C., Willis, N., and Wurzinger, R.

Subjects
Nuclear Experiment
Abstract

The total cross section of the pp -> pp eta' reaction has been measured at two energies near threshold by detecting the final protons in a magnetic spectrometer. The values obtained are about a factor of 70 less than for the corresponding eta production, in good agreement with the predictions of a one-pion-exchange model., Comment: 10 pages, Latex with 3 eps figures

Published
1998
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6. Eta-Helium Quasi-Bound States

Author

Willis, N., Bornec, Y. Le, Zghiche, A., Wilkin, C., Wurzinger, R., Bing, O., Boivin, M., Courtat, P., Gacougnolle, R., Hibou, F., Martin, J. M., Plouin, F., Tatischeff, B., and Yonnet, J.

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

The cross section and tensor analysing power t_20 of the d\vec{d}->eta 4He reaction have been measured at six c.m. momenta, 10 < p(eta) < 90 MeV/c. The threshold value of t_20 is consistent with 1/\sqrt{2}, which follows from parity conservation and Bose symmetry. The much slower momentum variation observed for the reaction amplitude, as compared to that for the analogous pd->eta 3He case, suggests strongly the existence of a quasi-bound state in the eta-4He system and optical model fits indicate that this probably also the case for eta-3He., Comment: LaTeX, uses elsart.sty, 10 pages, 3 Postscript figures, Submitted to Physics Letters B

Published
1997
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7. Degrading intestinal DAF-2 nearly doubles Caenorhabditis elegans lifespan without affecting development or reproduction

Author

Cheng Zhan, Wen-Hong Zhang, Jia-Wen Wang, Shao-Bing O. Zhang, Yue Sun, Yan-Ping Zhang, Meng-Qiu Dong, Pan Zhang, Tao Cai, and Qi Li

Subjects
Mutation, Mutant, Biology, Protein degradation, biology.organism_classification, medicine.disease_cause, Cell biology, Insulin receptor, medicine, biology.protein, Daf-2, Gene, Transcription factor, Caenorhabditis elegans
Abstract

SummaryTwenty-eight years following the breakthrough discovery that a single-gene mutation of daf-2 can double the lifespan of Caenorhabditis elegans, it remains unclear where this gene, which encodes an insulin/IGF-1 receptor, is expressed and where it acts to regulate aging. Here, by inserting DNA sequences of fluorescent tags into the genomic locus of daf-2 and that of its downstream transcription factor daf-16, we determined that both genes are expressed in most or all tissues from embryos through adulthood, in line with their diverse functions. Using tissue-specific auxin-induced protein degradation, we determined that both DAF-2 and DAF-16 act in the intestine to regulate organismal aging. Strikingly, loss of DAF-2 in the intestine nearly doubled C. elegans lifespan but did not produce the adverse developmental or reproductive phenotypes associated with genetic daf-2 mutants. These findings unify the mechanism of lifespan regulation by genes and that by dietary restriction, and begin to focus anti-aging research on nutrient supply.Highlightsdaf-2 and daf-16 are expressed in most or all cells of C. elegans using genome editing.DAF-2 and DAF-16 both regulate lifespan from the intestine as determined using auxin-induced protein degradation.Reduced insulin signaling in the intestine nearly doubles C. elegans lifespan without adverse effects on development or reproduction.Lifespan regulation by genes and dietary restriction are unified by intestinal supply of nutrients and metabolism.

Published
2021
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8. Chemical purification of molybdenum samples for the NEMO3 experiment

Author

Arnold, R., Augier, C., Baker, J., Barabash, A., Bing, O., Blum, D., Brudanin, V., Caffrey, A.J., Campagne, Jean-Eric, Caurier, E., Dassie, D., Egorov, V., Errahnmane, K., Filipova, T., Guyonnet, J.L., Hubert, F., Hubert, P., Jullian, Sophie, Kochetov, O., Kisel, I., Kornoukhov, V.N., Kovalenko, V., Kuzichev, V.F., Lalanne, D., Laplanche, F., Leccia, F., Linck, I., Longuemare, C., Marquet, Ch., Mauger, F., Nicholson, H.W., Nikolic-Audit, I., Pilugin, I., Piquemal, F., Reyss, J.-L., Riddle, C.L., Sarazin, X., Scheibling, F., Stekl, I., Suhonen, J., Sutton, C.S., Szklarz, G., Timkin, V., Tretyak, V., Umatov, V., Vanyushin, I., Vorobel, V., Vylov, Ts., Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Océan et Interfaces (OCEANIS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), NEMO, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]
Published
2001

9. Influence of neutrons and $\gamma$-rays in the Frejus underground laboratory on the NEMO experiment

Author

Marquet, Catherine, Piquemal, F., Arnold, R., Augier, C., Baker, J., Barabash, A., Bing, O., Blum, D., Brudanin, V., Caffrey, J., Campagne, Jean-Eric, Caurier, E., Dassie, D., Egorov, V., Errahmane, K., Eschbach, R., Filipova, T., Guyonnet, J.L., Jollet, C., Jullian, Sophie, Hubert, F., Hubert, P., Kisel, I., Kochetov, O., Kornoukhov, V.N., Kovalenko, V., Lalanne, D., Laplanche, D., Leccia, F., Linck, I., Longuemare, C., Mauger, F., Nicholson, H.W., Nikolic-Audit, I., Ohsumi, H., Pilugin, I., Reyss, J.L., Sarazin, X., Scheibling, F., Stekl, I., Suhonen, J., Sutton, C.S., Szklarz, G., Timkin, V., Tretyak, V., Umatov, V., Vala, L., Vanyushin, I., Vareille, A., Vorobel, V., Vylov, T., Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), NEMO, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Published
2001

10. Near-Threshold Production of $\omega$ Mesons in the $pp \to pp \omega$ Reaction

Author

Hibou, F., Bing, O., Boivin, M., Courtat, P., Gacougnolle, R., Le Bornec, Y., Martin, J M., Plouin, F., Tatischeff, B., Wilkin, C., Willis, N., Wurzinger, R., Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract

The total cross section for omega production in the pp -> pp omega reaction has been measured at five c.m. excess energies from 3.8 to 30 MeV. The energy dependence is easily understood in terms of a strong proton-proton final state interaction combined with a smearing over the width of the state. The ratio of near-threshold phi and omega production is consistent with the predictions of a one-pion-exchange model and the degree of violation of the OZI rule is similar to that found in the pi-p -> n omega/phi reactions., Comment: Report in LaTeX2e. 12 pages with 2 eps figures

Published
1999

11. RD-17 status report: ultra fast readout of scintillating fibres using upgraded position-sensitive photomultipliers

Author

Agoritsas, V, Akchurin, N, Bergdolt, A M, Bing, O, Bravar, A, Cardini, A, Cavasinni, V, Di Girolamo, B, Ditta, J, Dufournaud, J, Flaminio, Vincenzo, Giacomich, R, Gorin, A M, Khaustov, G V, Kuroda, K, Magaudda, D, Manuilov, I V, Newsom, C R, Okada, K, Okusawa, K, Önel, Y M, Penzo, Aldo L, Rappazzo, G F, Riazantsev, A V, Rykalin, V I, Salvato, G, Schiavon, R P, Sillou, D, Takeutchi, F, Tareb-Reyes, M, and Yoshida, T

Subjects
Detectors and Experimental Techniques
Published
1993

12. Protective effects of diltiazem on the mechanical performance of the hypoxic myocardium

Author

Cicogna, A. C., Carlos Roberto Padovani, Brooks, W. W., Schine, L., Robinson, K. G., Conrad, C. H., Gaasch, W. H., Bing, O. H. L., and Universidade Estadual Paulista (UNESP)

Subjects
hypoxic contracture, hypoxia, diltiazem, quiescence, isolated papillary muscle
Abstract

Made available in DSpace on 2022-04-28T19:53:57Z (GMT). No. of bitstreams: 0 Previous issue date: 1993-01-01 Departamento de Clinica Medica Faculdade de Medicine UNESP, 18618-000 Botucatu Departamento de Clinica Medica Faculdade de Medicine UNESP, 18618-000 Botucatu

Published
1993

13. Study of the ABC enhancement in the dd ->alpha X-0 reaction

Author

Wurzinger, R, Bing, O, Boivin, M, Courtat, P, Faldt, Goran, Gacougnolle, R, Gardestig, A, Hibou, F, Le, Bornec Y, Martin, JM, Plouin, F, Tatischeff, B, Wilkin, C, Willis, N, Yonnet, J, Zghiche, A, Wurzinger, R, Bing, O, Boivin, M, Courtat, P, Faldt, Goran, Gacougnolle, R, Gardestig, A, Hibou, F, Le, Bornec Y, Martin, JM, Plouin, F, Tatischeff, B, Wilkin, C, Willis, N, Yonnet, J, and Zghiche, A

Abstract

The dd --> alpha X0 reaction at beam energies close to the eta threshold shows very strong structure in the missing mass corresponding to the ABC enhancement. The deuteron tensor analysing power Ayy, and the slope of the v, Addresses: Wurzinger R, Univ Paris Sud, Inst Nucl Phys, IN2P3, F-91406 Orsay, France. Univ Paris Sud, Inst Nucl Phys, IN2P3, F-91406 Orsay, France. Natl Saturne Lab, F-91191 Gif Sur Yvette, France. Univ Strasbourg 1, CNRS, IN2P3, Inst Rech Subatom, F-6703

Published
1999

14. Comparison of eta and eta ' production in the pp -> pp eta(eta ') reactions near threshold

Author

Hibou, F, Bing, O, Boivin, M, Courtat, P, Faldt, Goran, Gacougnolle, R, Le, Bornec Y, Martin, JM, Moalem, A, Plouin, F, Taleb, A, Tatischeff, B, Wilkin, C, Willis, N, Wurzinger, R, Hibou, F, Bing, O, Boivin, M, Courtat, P, Faldt, Goran, Gacougnolle, R, Le, Bornec Y, Martin, JM, Moalem, A, Plouin, F, Taleb, A, Tatischeff, B, Wilkin, C, Willis, N, and Wurzinger, R

Abstract

The total cross section of the pp --> pp eta' reaction has been measured at two energies near threshold by detecting the final protons in a magnetic spectrometer. The values obtained are about a factor of 70 less than for the corresponding eta production, Addresses: Hibou F, Univ Strasbourg 1, IN2P3, CNRS, Inst Rech Subatom, BP 28, F-67037 Strasbourg 2, France. Univ Strasbourg 1, IN2P3, CNRS, Inst Rech Subatom, F-67037 Strasbourg 2, France. Natl Saturne Lab, F-91191 Gif Sur Yvette, France. CNRS, IN2P3, Ins

Published
1998

21. DISTRIBUTION OF CRYPTOSPORIDIUM PARVUM SPOROZOITE APICAL ORGANELLES DURING ATTACHMENT TO AND INTERNALIZATION BY CULTURED BILIARY EPITHELIAL CELLS.

Author

O'Hara, Steven P., Huang, Bing O., Xian-Ming Chen, Nelson, Jeremy, and Larusso, Nicholas F.

Subjects
EPITHELIAL cells, MICROBIAL invasiveness, ELECTRON microscopy, MORPHOLOGY, EPITHELIUM, ORGANELLES, CELL nuclei
Abstract

The article reports on the efforts to understand the active role for host cells during invasion strategy of C. parvum in the U.S. In an efforts to further understand the invasion of epithelia, experts characterized the presence and distribution of the apical organelles through the stages of attachment to, and internalization by, human biliary epithelia, using serial-section electron microscopy. The morphological observations presented here extend our understanding of parasite-specific processes that occur during attachment to, and internalization by, host epithelial cells.

Published
2005
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27. Neutron hole states in $^{6}_{\Lambda}$Li, $^{7}_{\Lambda}$Li, $^{9}_{\Lambda}$Be and $^{12}_{\Lambda}$C hypernuclei

Author

Bertini, R, Bing, O, Birien, P, Braune, K, Brückner, W, Chaumeaux, A, Faessler, M A, Frey, R W, Garreta, D, Ketel, T, Kilian, K, Mayer, B, Niewisch, J, Pietrzyk, B, Povh, B, Ritter, H G, and Uhrmacher, M

Subjects
Nuclear Experiment, Particle Physics - Experiment
Abstract

Neutron hole states in the 1s shell have been studied in the n(K/sup - /, pi /sup -/) Lambda strangeness-exchange reaction on /sup 6/Li, /sup 7/Li, /sup 9/Be, and /sup 12/C targets at the CERN Proton Synchrotron. The excitation energy and the width of the states as well as the differential cross section have been determined. The clear similarity with the 1s proton hole states observed in (p,2p) reactions indicates that the presence of the Lambda -particle can be taken into account within the weak-coupling model. In this way the (K/sup -/, pi /sup -/) reaction can be used for the study of Lambda -states as well as for the investigation of neutron hole states produced at very low momentum transfer. (22 refs).

Published
1981

33. Search for antiproton-nucleus states with ($\overline{p}$,p) reactions

Author

Garreta, D, Birien, P, Bruge, G, Chaumeaux, A, Drake, D M, Janouin, S, Legrand, Dominique, Lemaire, M C, Mayer, B, Pain, J, Peng, J C, Berrada, M, Bocquet, J P, Monnand, E, Mougey, J, Perrin, P, Aslanides, Elie, Bing, O, Lichtenstadt, J, and Yavin, A I

Subjects
Nuclear Physics
Published
1984

36. Hypernuclear production in the $(K^{-}, \pi^{-})$ reaction

Author

Bertini, R, Bing, O, Birien, P, Braune, K, Brückner, W, Catz, H, Chaumeaux, A, Faessler, M A, Frey, R W, Garreta, D, Ketel, T, Kilian, K, Mayer, B, Niewisch, J, Pietrzyk, B, Povh, B, Ritter, H G, and Uhrmacher, M

Subjects
Detectors and Experimental Techniques
Published
1980

44. PHYSICAL TRAINING AND CHRONIC HYPOXIA

Author

Maher, J. T., primary, Manchanda, S. O., additional, Ekblom, B., additional, Francesconi, R. P., additional, Powers, W. D., additional, Hartley, L. H., additional, and Bing, O. H. L., additional

Published
1976
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48. Exaggerated left ventricular dilation and reduced collagen deposition after myocardial infarction in mice lacking osteopontin.

Author

Trueblood NA, Xie Z, Communal C, Sam F, Ngoy S, Liaw L, Jenkins AW, Wang J, Sawyer DB, Bing OH, Apstein CS, Colucci WS, and Singh K

Subjects
Animals, Cardiac Volume, Cell Size, Collagen genetics, Collagen ultrastructure, Dilatation, Pathologic etiology, Dilatation, Pathologic pathology, Disease Models, Animal, Immunohistochemistry, In Situ Hybridization, In Situ Nick-End Labeling, In Vitro Techniques, Lung pathology, Mice, Mice, Inbred Strains, Mice, Knockout, Myocardial Infarction complications, Myocardial Infarction physiopathology, Myocardium metabolism, Myocardium pathology, Myocardium ultrastructure, Organ Size, Osteopontin, RNA, Messenger metabolism, Sialoglycoproteins genetics, Sialoglycoproteins metabolism, Survival Rate, Ventricular Dysfunction, Left etiology, Ventricular Dysfunction, Left physiopathology, Collagen metabolism, Dilatation, Pathologic physiopathology, Myocardial Infarction metabolism, Sialoglycoproteins deficiency, Ventricular Remodeling
Abstract

Osteopontin (OPN), an extracellular matrix protein, is expressed in the myocardium with hypertrophy and failure. We tested the hypothesis that OPN plays a role in left ventricular (LV) remodeling after myocardial infarction (MI). Accordingly, OPN expression and LV structural and functional remodeling were determined in wild-type (WT) and OPN knockout (KO) mice 4 weeks after MI. Northern analysis showed increased OPN expression in the infarcted region, peaking 3 days after MI and gradually decreasing over the next 28 days. In the remote LV, OPN expression was biphasic, with peaks at 3 and 28 days. In situ hybridization and immunohistochemical analyses showed increased OPN mRNA and protein primarily in the interstitium. Infarct size, heart weight, and survival were similar in KO and WT mice after MI (P=NS), whereas the lung wet weight/dry weight ratio was increased in the KO mice (P<0.005 versus sham-operated mice). Peak LV developed pressure was reduced to a similar degree after MI in the KO and WT mice. The number of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL)-positive myocytes was similar in KO and WT mice after MI. In contrast, post-MI LV chamber dilation was approximately twice as great in KO versus WT mice (P<0.001). Myocyte length increased after MI in WT mice (P<0.001) but not in KO mice. Electron microscopy showed increased collagen content in WT mice after MI but not in KO mice after MI. Type I collagen content was increased approximately 3-fold and approximately 7-fold in remote and infarcted regions, respectively, of WT hearts after MI but not in KO hearts (P<0.01 versus WT hearts). Likewise, Northern analyses showed increased collagen I(alpha(1)) mRNA after MI in remote regions of WT hearts but not in KO hearts. Thus, increased OPN expression plays an important role in regulating post-MI LV remodeling, at least in part, by promoting collagen synthesis and accumulation.

Published
2001
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49. Matrix gene expression and decompensated heart failure: the aged SHR model.

Author

Boluyt MO and Bing OH

Subjects
Animals, Cardiomegaly metabolism, Gene Expression, Heart Failure drug therapy, Rats, Aging metabolism, Disease Models, Animal, Extracellular Matrix metabolism, Heart Failure metabolism, Myocardium metabolism, Rats, Inbred SHR
Abstract

Impaired functional performance despite hypertrophic enlargement, and an excessive accumulation of extracellular matrix, are hallmarks of the decompensated failing heart. Age is the leading risk factor for heart failure, and there is evidence suggesting that a number of age-associated changes in the cardiac phenotype predispose the heart to failure. The spontaneously hypertensive rat (SHR) exhibits compensated cardiac hypertrophy followed by a transition to heart failure in the last quartile of the lifespan, and thus provides a useful model of the transition from stable compensated hypertrophy to decompensated heart failure in the context of aging. The transition to failure in the SHR is accompanied by marked changes in the expression of an array of genes in the heart, including increased expression of a number of genes associated with the extracellular matrix. Drug treatments that prevent or reverse matrix gene expression in the SHR heart improve myocardial function and survival. The aged SHR model of decompensated heart failure has provided insight into the role of the extracellular matrix in the transition to failure, and can be useful to further investigate the mechanistic bases of heart failure, as well as to evaluate the potential efficacy of novel therapeutic approaches to the treatment of heart failure.

Published
2000
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50. Effects of mCPP on the extracellular concentrations of serotonin and dopamine in rat brain.

Author

Eriksson E, Engberg G, Bing O, and Nissbrandt H

Subjects
Animals, Brain metabolism, Corpus Striatum drug effects, Corpus Striatum metabolism, Electrophysiology, Hippocampus drug effects, Hippocampus metabolism, Male, Microdialysis, Neurons metabolism, Neurons physiology, Nucleus Accumbens drug effects, Nucleus Accumbens metabolism, Rats, Rats, Sprague-Dawley, Brain drug effects, Dopamine metabolism, Piperazines pharmacology, Serotonin metabolism, Serotonin Receptor Agonists pharmacology
Abstract

Intravenous administration of m-chloro-phenylpiperazine (mCPP) (0.25 or 2.5 mg/kg) induced a marked and dose-related increase in extracellular concentrations of serotonin in hippocampus (300-1,400% of baseline) as measured using in vivo microdialysis in awake male Wistar rats of the spontaneously hypertensive (SH) strain. Indicating that the effect of mCPP was caused by a reversal of the serotonin transporter, it was antagonized by pretreatment with the serotonin re-uptake inhibitor citalopram (10 mg/kg) but was unaffected by local administration of the sodium channel blocker tetrodotoxin (TTX; 1 microns). mCPP was also shown to induce an increase in extracellular concentrations of dopamine in the nucleus accumbens and the striatum of SH rats and in the nucleus accumbens of rats of the Sprague-Dawley (SD) strain; this effect of mCPP was, however, much weaker (125-170% of baseline) than the effect on serotonin; moreover, it seems to be TTX-sensitive. In anesthetized SD rats, mCPP induced a moderate reduction of nigral dopamine cell firing rate; supporting the assumption that this effect is secondary to the observed increase in dopamine release, it was blocked by pretreatment either with the dopamine synthesis inhibitor alpha-methyl-para-tyrosine or with the dopamine D2 receptor antagonist haloperidol. In conclusion, the results suggest that mCPP induces a marked, TTX-insensitive increase in serotonin release in rat brain, but only a modest and TTX-sensitive increase in the extracellular levels of dopamine.

Published
1999
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