1
|
Blenkmann AO, Leske SL, Llorens A, Lin JJ, Chang EF, Brunner P, Schalk G, Ivanovic J, Larsson PG, Knight RT, Endestad T, Solbakk AK. Anatomical registration of intracranial electrodes. Robust model-based localization and deformable smooth brain-shift compensation methods. J Neurosci Methods 2024; 404:110056. [PMID: 38224783 DOI: 10.1016/j.jneumeth.2024.110056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 11/27/2023] [Accepted: 01/03/2024] [Indexed: 01/17/2024]
Abstract
BACKGROUND Intracranial electrodes are typically localized from post-implantation CT artifacts. Automatic algorithms localizing low signal-to-noise ratio artifacts and high-density electrode arrays are missing. Additionally, implantation of grids/strips introduces brain deformations, resulting in registration errors when fusing post-implantation CT and pre-implantation MR images. Brain-shift compensation methods project electrode coordinates to cortex, but either fail to produce smooth solutions or do not account for brain deformations. NEW METHODS We first introduce GridFit, a model-based fitting approach that simultaneously localizes all electrodes' CT artifacts in grids, strips, or depth arrays. Second, we present CEPA, a brain-shift compensation algorithm combining orthogonal-based projections, spring-mesh models, and spatial regularization constraints. RESULTS We tested GridFit on ∼6000 simulated scenarios. The localization of CT artifacts showed robust performance under difficult scenarios, such as noise, overlaps, and high-density implants (<1 mm errors). Validation with data from 20 challenging patients showed 99% accurate localization of the electrodes (3160/3192). We tested CEPA brain-shift compensation with data from 15 patients. Projections accounted for simple mechanical deformation principles with < 0.4 mm errors. The inter-electrode distances smoothly changed across neighbor electrodes, while changes in inter-electrode distances linearly increased with projection distance. COMPARISON WITH EXISTING METHODS GridFit succeeded in difficult scenarios that challenged available methods and outperformed visual localization by preserving the inter-electrode distance. CEPA registration errors were smaller than those obtained for well-established alternatives. Additionally, modeling resting-state high-frequency activity in five patients further supported CEPA. CONCLUSION GridFit and CEPA are versatile tools for registering intracranial electrode coordinates, providing highly accurate results even in the most challenging implantation scenarios. The methods are implemented in the iElectrodes open-source toolbox.
Collapse
Affiliation(s)
- Alejandro Omar Blenkmann
- Department of Psychology, University of Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time, and Motion, University of Oslo, Norway.
| | - Sabine Liliana Leske
- Department of Musicology, University of Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time, and Motion, University of Oslo, Norway; Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Anaïs Llorens
- Department of Psychology, University of Oslo, Norway; Department of Psychology and the Helen Wills Neuroscience Institute, University of California, Berkeley, USA; Université de Franche-Comté, SUPMICROTECH, CNRS, Institut FEMTO-ST, 25000 Besançon, France; Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Team TURC, 75014 Paris, France
| | - Jack J Lin
- Department of Neurology and Center for Mind and Brain, University of California, Davis, USA
| | - Edward F Chang
- Department of Neurological Surgery, University of California, San Francisco, USA
| | - Peter Brunner
- Department of Neurology, Albany Medical College, Albany, NY, USA; National Center for Adaptive Neurotechnologies, Albany, NY, USA; Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Gerwin Schalk
- Department of Neurology, Albany Medical College, Albany, NY, USA; National Center for Adaptive Neurotechnologies, Albany, NY, USA; Tianqiao and Chrissy Chen Institute, Chen Frontier Lab for Applied Neurotechnology, Shanghai, China; Fudan University/Huashan Hospital, Department of Neurosurgery, Shanghai, China
| | | | | | - Robert Thomas Knight
- Department of Psychology and the Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Tor Endestad
- Department of Psychology, University of Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time, and Motion, University of Oslo, Norway; Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Anne-Kristin Solbakk
- Department of Psychology, University of Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time, and Motion, University of Oslo, Norway; Department of Neurosurgery, Oslo University Hospital, Norway; Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| |
Collapse
|
2
|
Llorens A, Bellier L, Blenkmann AO, Ivanovic J, Larsson PG, Lin JJ, Endestad T, Solbakk AK, Knight RT. Decision and response monitoring during working memory are sequentially represented in the human insula. iScience 2023; 26:107653. [PMID: 37674986 PMCID: PMC10477069 DOI: 10.1016/j.isci.2023.107653] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 06/05/2023] [Accepted: 07/11/2023] [Indexed: 09/08/2023] Open
Abstract
Emerging research supports a role of the insula in human cognition. Here, we used intracranial EEG to investigate the spatiotemporal dynamics in the insula during a verbal working memory (vWM) task. We found robust effects for theta, beta, and high frequency activity (HFA) during probe presentation requiring a decision. Theta band activity showed differential involvement across left and right insulae while sequential HFA modulations were observed along the anteroposterior axis. HFA in anterior insula tracked decision making and subsequent HFA was observed in posterior insula after the behavioral response. Our results provide electrophysiological evidence of engagement of different insula subregions in both decision-making and response monitoring during vWM and expand our knowledge of the role of the insula in complex human behavior.
Collapse
Affiliation(s)
- Anaïs Llorens
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
- Université de Franche-Comté, SUPMICROTECH, CNRS, Institut FEMTO-ST, 25000 Besançon, France
- Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Team TURC, 75014 Paris, France
| | - Ludovic Bellier
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Alejandro O. Blenkmann
- Department of Psychology, University of Oslo, Oslo, Norway
- RITMO Center for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
| | | | - Pål G. Larsson
- Department of Neurosurgery, Oslo University Hospital, Oslo, Norway
| | - Jack J. Lin
- Department of Neurology and Center for Mind and Brain, University of California, Davis, Davis, CA, USA
| | - Tor Endestad
- Department of Psychology, University of Oslo, Oslo, Norway
- RITMO Center for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
- Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Anne-Kristin Solbakk
- Department of Neurosurgery, Oslo University Hospital, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
- RITMO Center for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
- Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Robert T. Knight
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
- Department of Psychology, University of California, Berkeley, Berkeley, CA, USA
| |
Collapse
|
3
|
Bellier L, Llorens A, Marciano D, Gunduz A, Schalk G, Brunner P, Knight RT. Music can be reconstructed from human auditory cortex activity using nonlinear decoding models. PLoS Biol 2023; 21:e3002176. [PMID: 37582062 PMCID: PMC10427021 DOI: 10.1371/journal.pbio.3002176] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 05/30/2023] [Indexed: 08/17/2023] Open
Abstract
Music is core to human experience, yet the precise neural dynamics underlying music perception remain unknown. We analyzed a unique intracranial electroencephalography (iEEG) dataset of 29 patients who listened to a Pink Floyd song and applied a stimulus reconstruction approach previously used in the speech domain. We successfully reconstructed a recognizable song from direct neural recordings and quantified the impact of different factors on decoding accuracy. Combining encoding and decoding analyses, we found a right-hemisphere dominance for music perception with a primary role of the superior temporal gyrus (STG), evidenced a new STG subregion tuned to musical rhythm, and defined an anterior-posterior STG organization exhibiting sustained and onset responses to musical elements. Our findings show the feasibility of applying predictive modeling on short datasets acquired in single patients, paving the way for adding musical elements to brain-computer interface (BCI) applications.
Collapse
Affiliation(s)
- Ludovic Bellier
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California, United States of America
| | - Anaïs Llorens
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California, United States of America
| | - Déborah Marciano
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California, United States of America
| | - Aysegul Gunduz
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida, United States of America
| | - Gerwin Schalk
- Department of Neurology, Albany Medical College, Albany, New York, United States of America
| | - Peter Brunner
- Department of Neurology, Albany Medical College, Albany, New York, United States of America
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri, United States of America
- National Center for Adaptive Neurotechnologies, Albany, New York, United States of America
| | - Robert T. Knight
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California, United States of America
- Department of Psychology, University of California, Berkeley, Berkeley, California, United States of America
| |
Collapse
|
4
|
Fuhrer J, Glette K, Llorens A, Endestad T, Solbakk AK, Blenkmann AO. Quantifying evoked responses through information-theoretical measures. Front Neuroinform 2023; 17:1128866. [PMID: 37287586 PMCID: PMC10242156 DOI: 10.3389/fninf.2023.1128866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 05/04/2023] [Indexed: 06/09/2023] Open
Abstract
Information theory is a viable candidate to advance our understanding of how the brain processes information generated in the internal or external environment. With its universal applicability, information theory enables the analysis of complex data sets, is free of requirements about the data structure, and can help infer the underlying brain mechanisms. Information-theoretical metrics such as Entropy or Mutual Information have been highly beneficial for analyzing neurophysiological recordings. However, a direct comparison of the performance of these methods with well-established metrics, such as the t-test, is rare. Here, such a comparison is carried out by evaluating the novel method of Encoded Information with Mutual Information, Gaussian Copula Mutual Information, Neural Frequency Tagging, and t-test. We do so by applying each method to event-related potentials and event-related activity in different frequency bands originating from intracranial electroencephalography recordings of humans and marmoset monkeys. Encoded Information is a novel procedure that assesses the similarity of brain responses across experimental conditions by compressing the respective signals. Such an information-based encoding is attractive whenever one is interested in detecting where in the brain condition effects are present.
Collapse
Affiliation(s)
- Julian Fuhrer
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
- Department of Informatics, University of Oslo, Oslo, Norway
| | - Kyrre Glette
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
- Department of Informatics, University of Oslo, Oslo, Norway
| | - Anaïs Llorens
- Helen Wills Neuroscience Institute and Department of Psychology, University of California, Berkeley, Berkeley, CA, United States
| | - Tor Endestad
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Neurosurgery, Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Anne-Kristin Solbakk
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Neurosurgery, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Alejandro Omar Blenkmann
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
| |
Collapse
|
5
|
Blenkmann AO, Leske SL, Llorens A, Lin JJ, Chang E, Brunner P, Schalk G, Ivanovic J, Larsson PG, Knight RT, Endestad T, Solbakk AK. Anatomical registration of intracranial electrodes. Robust model-based localization and deformable smooth brain-shift compensation methods. bioRxiv 2023:2023.05.08.539503. [PMID: 37214984 PMCID: PMC10197594 DOI: 10.1101/2023.05.08.539503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Precise electrode localization is important for maximizing the utility of intracranial EEG data. Electrodes are typically localized from post-implantation CT artifacts, but algorithms can fail due to low signal-to-noise ratio, unrelated artifacts, or high-density electrode arrays. Minimizing these errors usually requires time-consuming visual localization and can still result in inaccurate localizations. In addition, surgical implantation of grids and strips typically introduces non-linear brain deformations, which result in anatomical registration errors when post-implantation CT images are fused with the pre-implantation MRI images. Several projection methods are currently available, but they either fail to produce smooth solutions or do not account for brain deformations. To address these shortcomings, we propose two novel algorithms for the anatomical registration of intracranial electrodes that are almost fully automatic and provide highly accurate results. We first present GridFit, an algorithm that simultaneously localizes all contacts in grids, strips, or depth arrays by fitting flexible models to the electrodes' CT artifacts. We observed localization errors of less than one millimeter (below 8% relative to the inter-electrode distance) and robust performance under the presence of noise, unrelated artifacts, and high-density implants when we ran ~6000 simulated scenarios. Furthermore, we validated the method with real data from 20 intracranial patients. As a second registration step, we introduce CEPA, a brain-shift compensation algorithm that combines orthogonal-based projections, spring-mesh models, and spatial regularization constraints. When tested with real data from 15 patients, anatomical registration errors were smaller than those obtained for well-established alternatives. Additionally, CEPA accounted simultaneously for simple mechanical deformation principles, which is not possible with other available methods. Inter-electrode distances of projected coordinates smoothly changed across neighbor electrodes, while changes in inter-electrode distances linearly increased with projection distance. Moreover, in an additional validation procedure, we found that modeling resting-state high-frequency activity (75-145 Hz ) in five patients further supported our new algorithm. Together, GridFit and CEPA constitute a versatile set of tools for the registration of subdural grid, strip, and depth electrode coordinates that provide highly accurate results even in the most challenging implantation scenarios. The methods presented here are implemented in the iElectrodes open-source toolbox, making their use simple, accessible, and straightforward to integrate with other popular toolboxes used for analyzing electrophysiological data.
Collapse
Affiliation(s)
- Alejandro Omar Blenkmann
- Department of Psychology, University of Oslo, Norway
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time, and Motion, University of Oslo, Norway
| | - Sabine Liliana Leske
- Department of Musicology, University of Oslo, Norway
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time, and Motion, University of Oslo, Norway
| | - Anaïs Llorens
- Department of Psychology, University of Oslo, Norway
- Department of Psychology and the Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Jack J. Lin
- Department of Neurology and Center for Mind and Brain, University of California, Davis, USA
| | - Edward Chang
- Department of Neurological Surgery, University of California, San Francisco, USA
| | - Peter Brunner
- Department of Neurology, Albany Medical College, Albany, NY, USA
- National Center for Adaptive Neurotechnologies, Albany, NY, USA
| | - Gerwin Schalk
- Department of Neurology, Albany Medical College, Albany, NY, USA
- National Center for Adaptive Neurotechnologies, Albany, NY, USA
- Tianqiao and Chrissy Chen Institute, Chen Frontier Lab for Applied Neurotechnology, Shanghai, China
- Fudan University/Huashan Hospital, Department of Neurosurgery, Shanghai, China
| | | | | | - Robert Thomas Knight
- Department of Psychology and the Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Tor Endestad
- Department of Psychology, University of Oslo, Norway
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time, and Motion, University of Oslo, Norway
- Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Anne-Kristin Solbakk
- Department of Psychology, University of Oslo, Norway
- RITMO Centre for Interdisciplinary Studies in Rhythm, Time, and Motion, University of Oslo, Norway
- Department of Neurosurgery, Oslo University Hospital, Norway
- Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| |
Collapse
|
6
|
Llorens A, Tzovara A, Bellier L, Bhaya-Grossman I, Bidet-Caulet A, Chang WK, Cross ZR, Dominguez-Faus R, Flinker A, Fonken Y, Gorenstein MA, Holdgraf C, Hoy CW, Ivanova MV, Jimenez RT, Jun S, Kam JWY, Kidd C, Marcelle E, Marciano D, Martin S, Myers NE, Ojala K, Perry A, Pinheiro-Chagas P, Riès SK, Saez I, Skelin I, Slama K, Staveland B, Bassett DS, Buffalo EA, Fairhall AL, Kopell NJ, Kray LJ, Lin JJ, Nobre AC, Riley D, Solbakk AK, Wallis JD, Wang XJ, Yuval-Greenberg S, Kastner S, Knight RT, Dronkers NF. Gender bias in academia: A lifetime problem that needs solutions. Neuron 2021; 109:2047-2074. [PMID: 34237278 PMCID: PMC8553227 DOI: 10.1016/j.neuron.2021.06.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/19/2020] [Accepted: 06/01/2021] [Indexed: 11/18/2022]
Abstract
Despite increased awareness of the lack of gender equity in academia and a growing number of initiatives to address issues of diversity, change is slow, and inequalities remain. A major source of inequity is gender bias, which has a substantial negative impact on the careers, work-life balance, and mental health of underrepresented groups in science. Here, we argue that gender bias is not a single problem but manifests as a collection of distinct issues that impact researchers' lives. We disentangle these facets and propose concrete solutions that can be adopted by individuals, academic institutions, and society.
Collapse
Affiliation(s)
- Anaïs Llorens
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA.
| | - Athina Tzovara
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Institute for Computer Science, University of Bern, Bern, Switzerland; Sleep Wake Epilepsy Center | NeuroTec, Department of Neurology, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland.
| | - Ludovic Bellier
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Ilina Bhaya-Grossman
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, USA
| | - Aurélie Bidet-Caulet
- Brain Dynamics and Cognition Team, Lyon Neuroscience Research Center, CRNL, INSERM U1028, CNRS UMR 5292, University of Lyon, Lyon, France
| | - William K Chang
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Zachariah R Cross
- Cognitive and Systems Neuroscience Research Hub, University of South Australia, Adelaide, SA, Australia
| | | | | | - Yvonne Fonken
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Department of Psychiatry, University of Oxford, Oxford, UK
| | - Mark A Gorenstein
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Department of Psychology, University of California, Berkeley, Berkeley, CA, USA
| | - Chris Holdgraf
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; The Berkeley Institute for Data Science, Berkeley, CA, USA
| | - Colin W Hoy
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Maria V Ivanova
- Department of Psychology, University of California, Berkeley, Berkeley, CA, USA
| | - Richard T Jimenez
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Soyeon Jun
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Department of Brain and Cognitive Science College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Julia W Y Kam
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Department of Psychology, University of Calgary, Calgary, AB, Canada
| | - Celeste Kidd
- Department of Psychology, University of California, Berkeley, Berkeley, CA, USA
| | - Enitan Marcelle
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Deborah Marciano
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Haas School of Business, University of California, Berkeley, Berkeley, CA, USA
| | - Stephanie Martin
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Department of Cognitive Science, University of California, San Diego, San Diego, CA, USA
| | - Nicholas E Myers
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Department of Experimental Psychology and Oxford Centre for Human Brain Activity, Department of Psychiatry, Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
| | - Karita Ojala
- Institute of Systems Neuroscience, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anat Perry
- Department of Psychology, the Hebrew University of Jerusalem, Jerusalem, Israel
| | - Pedro Pinheiro-Chagas
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford Human, Stanford University, Stanford, CA, USA
| | - Stephanie K Riès
- School of Speech, Language, and Hearing Sciences and Center for Clinical and Cognitive Neuroscience, San Diego State University, San Diego, CA, USA
| | - Ignacio Saez
- Department of Neurosurgery, University of California Davis, Sacramento, CA, USA
| | - Ivan Skelin
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Katarina Slama
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Brooke Staveland
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Haas School of Business, University of California, Berkeley, Berkeley, CA, USA
| | - Danielle S Bassett
- Departments of Bioengineering, Electrical & Systems Engineering, Physics & Astronomy, Psychiatry, and Neurology, University of Pennsylvania, Philadelphia, PA, USA; Santa Fe Institute, Santa Fe, NM 87501, USA
| | - Elizabeth A Buffalo
- Department of Physiology and Biophysics and School of Medicine, Washington National Primate Research Center, University of Washington, Seattle, WA, USA
| | - Adrienne L Fairhall
- Department of Physiology and Biophysics and Computational Neuroscience Center, University of Washington, Seattle, WA 98195, USA
| | - Nancy J Kopell
- Department of Mathematics & Statistics, Boston University, Boston, MA, USA
| | - Laura J Kray
- Haas School of Business, University of California, Berkeley, Berkeley, CA, USA
| | - Jack J Lin
- Comprehensive Epilepsy Program, Department of Neurology, University of California, Irvine, Irvine, CA, USA; Department of Biomedical Engineering, Henry Samueli School of Engineering, Irvine, CA, USA
| | - Anna C Nobre
- Department of Experimental Psychology and Oxford Centre for Human Brain Activity, Department of Psychiatry, Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
| | - Dylan Riley
- Department of Sociology, University of California, Berkeley, Berkeley, CA 94720-1980, USA
| | - Anne-Kristin Solbakk
- Department of Psychology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Department of Neurosurgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway; Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Joni D Wallis
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Department of Psychology, University of California, Berkeley, Berkeley, CA, USA
| | - Xiao-Jing Wang
- Center for Neural Science, New York University, 4 Washington Place, New York, NY 10003, USA
| | - Shlomit Yuval-Greenberg
- School of Psychological Sciences and Sagol School of Neuroscience, Tel Aviv University, Ramat Aviv, 6997801 Tel Aviv-Yafo, Israel
| | - Sabine Kastner
- Princeton Neuroscience Institute and Department of Psychology, Princeton University, Princeton, NJ 08544, USA
| | - Robert T Knight
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA; Department of Psychology, University of California, Berkeley, Berkeley, CA, USA
| | - Nina F Dronkers
- Department of Psychology, University of California, Berkeley, Berkeley, CA, USA; Department of Neurology, University of California, Davis, Sacramento, CA, USA
| |
Collapse
|
7
|
Solbakk AK, Lubell J, Leske S, Funderud I, Llorens A, Blenkmann AO, Foldal MD, Meling TR, Knight RT, Endestad T. Monitoring of Self-Paced Action Timing and Sensory Outcomes After Lesions to the Orbitofrontal Cortex. J Cogn Neurosci 2021; 33:1956-1975. [PMID: 34375421 DOI: 10.1162/jocn_a_01733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Anticipation, monitoring, and evaluation of the outcome of one's actions are at the core of proactive control. Individuals with lesions to OFC often demonstrate behaviors that indicate a lack of recognition or concern for the negative effects of their actions. Altered action timing has also been reported in these patients. We investigated the role of OFC in predicting and monitoring the sensory outcomes of self-paced actions. We studied patients with focal OFC lesions (n = 15) and healthy controls (n = 20) while they produced actions that infrequently evoked unexpected outcomes. Participants performed a self-paced, random generation task where they repeatedly pressed right and left buttons that were associated with specific sensory outcomes: a 1- and 2-kHz tone, respectively. Occasional unexpected action outcomes occurred (mismatch) that inverted the learned button-tone association (match). We analyzed ERPs to the expected and unexpected outcomes as well as action timing. Neither group showed post-mismatch slowing of button presses, but OFC patients had a higher number of fast button presses, indicating that they were inferior to controls at producing regularly timed actions. Mismatch trials elicited enhanced N2b-P3a responses across groups as indicated by the significant main effect of task condition. Planned within-group analyses showed, however, that patients did not have a significant condition effect, suggesting that the result of the omnibus analysis was driven primarily by the controls. Altogether, our findings indicate that monitoring of action timing and the sensory outcomes of self-paced actions as indexed by ERPs is impacted by OFC damage.
Collapse
Affiliation(s)
- Anne-Kristin Solbakk
- University of Oslo, Norway.,Oslo University Hospital-Rikshospitalet, Norway.,Helgeland Hospital, Mosjøen, Norway
| | - James Lubell
- University of Oslo, Norway.,Aarhus University, Aarhus, Denmark
| | | | - Ingrid Funderud
- University of Oslo, Norway.,Helgeland Hospital, Mosjøen, Norway
| | - Anaïs Llorens
- Oslo University Hospital-Rikshospitalet, Norway.,University of California at Berkeley
| | | | | | | | | | - Tor Endestad
- University of Oslo, Norway.,Helgeland Hospital, Mosjøen, Norway
| |
Collapse
|
8
|
Foldal MD, Blenkmann AO, Llorens A, Knight RT, Solbakk AK, Endestad T. The brain tracks auditory rhythm predictability independent of selective attention. Sci Rep 2020; 10:7975. [PMID: 32409738 PMCID: PMC7224206 DOI: 10.1038/s41598-020-64758-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 04/07/2020] [Indexed: 11/16/2022] Open
Abstract
The brain responds to violations of expected rhythms, due to extraction- and prediction of the temporal structure in auditory input. Yet, it is unknown how probability of rhythm violations affects the overall rhythm predictability. Another unresolved question is whether predictive processes are independent of attention processes. In this study, EEG was recorded while subjects listened to rhythmic sequences. Predictability was manipulated by changing the stimulus-onset-asynchrony (SOA deviants) for given tones in the rhythm. When SOA deviants were inserted rarely, predictability remained high, whereas predictability was lower with more frequent SOA deviants. Dichotic tone-presentation allowed for independent manipulation of attention, as specific tones of the rhythm were presented to separate ears. Attention was manipulated by instructing subjects to attend to tones in one ear only, while keeping the rhythmic structure of tones constant. The analyses of event-related potentials revealed an attenuated N1 for tones when rhythm predictability was high, while the N1 was enhanced by attention to tones. Bayesian statistics revealed no interaction between predictability and attention. A right-lateralization of attention effects, but not predictability effects, suggested potentially different cortical processes. This is the first study to show that probability of rhythm violation influences rhythm predictability, independent of attention.
Collapse
Affiliation(s)
- Maja D Foldal
- Department of Psychology, University of Oslo, Oslo, Norway. .,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway.
| | - Alejandro O Blenkmann
- Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
| | - Anaïs Llorens
- Department of Psychology, University of Oslo, Oslo, Norway.,Department of Neurosurgery, Oslo University Hospital, Oslo, Norway.,Department of Psychology and the Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, USA
| | - Robert T Knight
- Department of Psychology and the Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, USA
| | - Anne-Kristin Solbakk
- Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway.,Department of Neurosurgery, Oslo University Hospital, Oslo, Norway.,Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Tor Endestad
- Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway.,Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| |
Collapse
|
9
|
Sibila M, Guevara G, Cuadrado R, Pleguezuelos P, Pérez D, Pérez de Rozas A, Huerta E, Llorens A, Valero O, Pérez M, López C, Krejci R, Segalés J. Comparison of Mycoplasma hyopneumoniae and porcine circovirus 2 commercial vaccines efficacy when applied separate or combined under experimental conditions. Porcine Health Manag 2020; 6:11. [PMID: 32391165 PMCID: PMC7197127 DOI: 10.1186/s40813-020-00148-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 03/04/2020] [Indexed: 02/07/2023] Open
Abstract
Background Mycoplasma hyopneumoniae (Mhyo) and Porcine circovirus 2 (PCV-2) are two of the most significant infectious agents causing economic losses in the weaning to slaughter period. Due to their similar vaccination age, the objective of this study was to assess the efficacy of two already existing Mhyo (Hyogen®) and PCV-2 (Circovac®) vaccines when administered separately or combined (RTM) by means of Mhyo or PCV-2 experimental challenges. Results Seven groups of animals were included in the study, being three of them challenged with PCV-2, three with Mhyo and one composed of non-challenged, non-vaccinated pigs. Within each experimental challenge, non-vaccinated (NV) groups were compared with double vaccinated groups using the commercial products separated (VS) or combined (VC). Both vaccinated groups showed significant differences for most parameters measured regarding PCV-2 (serology, percentage of infected animals and viral load in tissues) and Mhyo (serology and gross lesions) when compared to NV groups. VS and VC offered similar results, being only significantly different the PCV-2 antibody values at different time points (higher in the VS group) of the study, although not at the termination day (21 days post-PCV-2 inoculation). Conclusion The present study expands the knowledge on the possibility of using two separate Mhyo and PCV-2 commercial vaccines as a RTM product, which offered equivalent virological, immunological and pathological outcomes as compared to these vaccines when used by separate.
Collapse
Affiliation(s)
- M Sibila
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - G Guevara
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - R Cuadrado
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - P Pleguezuelos
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - D Pérez
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - A Pérez de Rozas
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - E Huerta
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - A Llorens
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - O Valero
- 3Servei d'Estadística Aplicada, Universitat Autònoma de Barcelona, Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
| | - M Pérez
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain
| | - C López
- 1IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain.,4Departament de Sanitat i Anatomia Animals, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
| | - R Krejci
- 5Ceva, La Ballastiere-BP, 126, 33501 Libourne Cedex, France
| | - J Segalés
- OIE Collaborating Centre for the Research and Control of Emerging and Re-emerging Swine Diseases in Europe (IRTA-CReSA), Bellaterra, Barcelona, Spain.,4Departament de Sanitat i Anatomia Animals, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.,6UAB, Centre de Recerca en Sanitat Animal (CReSA, IRTA- UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
| |
Collapse
|
10
|
Llorens A, Funderud I, Blenkmann AO, Lubell J, Foldal M, Leske S, Huster R, Meling TR, Knight RT, Solbakk AK, Endestad T. Preservation of Interference Effects in Working Memory After Orbitofrontal Damage. Front Hum Neurosci 2020; 13:445. [PMID: 31998097 PMCID: PMC6960483 DOI: 10.3389/fnhum.2019.00445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 12/03/2019] [Indexed: 11/13/2022] Open
Abstract
Orbitofrontal cortex (OFC) is implicated in multiple cognitive processes, including inhibitory control, context memory, recency judgment, and choice behavior. Despite an emerging understanding of the role of OFC in memory and executive control, its necessity for core working memory (WM) operations remains undefined. Here, we assessed the impact of OFC damage on interference effects in WM using a Recent Probes task based on the Sternberg item-recognition task (1966). Subjects were asked to memorize a set of letters and then indicate whether a probe letter was presented in a particular set. Four conditions were created according to the forthcoming response (“yes”/“no”) and the recency of the probe (presented in the previous trial set or not). We compared behavioral and electroencephalography (EEG) responses between healthy subjects (n = 14) and patients with bilateral OFC damage (n = 14). Both groups had the same recency pattern of slower reaction time (RT) when the probe was presented in the previous trial but not in the current one, reflecting the proactive interference (PI). The within-group electrophysiological results showed no condition difference during letter encoding and maintenance. In contrast, event-related potentials (ERPs) to probes showed distinct within-group condition effects, and condition by group effects. The response and recency effects for controls occurred within the same time window (300–500 ms after probe onset) and were observed in two distinct spatial groups including right centro-posterior and left frontal electrodes. Both clusters showed ERP differences elicited by the response effect, and one cluster was also sensitive to the recency manipulation. Condition differences for the OFC group involved two different clusters, encompassing only left hemisphere electrodes and occurring during two consecutive time windows (345–463 ms and 565–710 ms). Both clusters were sensitive to the response effect, but no recency effect was found despite the behavioral recency effect. Although the groups had different electrophysiological responses, the maintenance of letters in WM, the evaluation of the context of the probe, and the decision to accept or reject a probed letter were preserved in OFC patients. The results suggest that neural reorganization may contribute to intact recency judgment and response after OFC damage.
Collapse
Affiliation(s)
- Anaïs Llorens
- Department of Neurosurgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway.,Department of Psychology, University of Oslo, Oslo, Norway.,Department of Psychology, Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
| | - Ingrid Funderud
- Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
| | - Alejandro O Blenkmann
- Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
| | - James Lubell
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Maja Foldal
- Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
| | - Sabine Leske
- Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
| | - Rene Huster
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Torstein R Meling
- Department of Neurosurgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway.,Department of Psychology, University of Oslo, Oslo, Norway.,Faculty of Medicine, University of Oslo, Oslo, Norway.,Service de Neurochirurgie, Hôpitaux Universitaires de Genève, Genève, Switzerland
| | - Robert T Knight
- Department of Psychology, Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States
| | - Anne-Kristin Solbakk
- Department of Neurosurgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway.,Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway.,Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| | - Tor Endestad
- Department of Psychology, University of Oslo, Oslo, Norway.,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway.,Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway
| |
Collapse
|
11
|
Blenkmann AO, Collavini S, Lubell J, Llorens A, Funderud I, Ivanovic J, Larsson PG, Meling TR, Bekinschtein T, Kochen S, Endestad T, Knight RT, Solbakk AK. Auditory deviance detection in the human insula: An intracranial EEG study. Cortex 2019; 121:189-200. [PMID: 31629197 DOI: 10.1016/j.cortex.2019.09.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 06/24/2019] [Accepted: 09/01/2019] [Indexed: 11/27/2022]
Abstract
The human insula is known to be involved in auditory processing, but knowledge about its precise functional role and the underlying electrophysiology is limited. To assess its role in automatic auditory deviance detection we analyzed the EEG high frequency activity (HFA; 75-145 Hz) and ERPs from 90 intracranial insular channels across 16 patients undergoing pre-surgical intracranial monitoring for epilepsy treatment. Subjects passively listened to a stream of standard and deviant tones differing in four physical dimensions: intensity, frequency, location or time. HFA responses to auditory stimuli were found in the short and long gyri, and the anterior, superior, and inferior segments of the circular sulcus of the insular cortex. Only a subset of channels in the inferior segment of the circular sulcus of the insula showed HFA deviance detection responses, i.e., a greater and longer latency response to specific deviants relative to standards. Auditory deviancy processing was also later in the insula when compared with the superior temporal cortex. ERP results were more widespread and supported the HFA insular findings. These results provide evidence that the human insula is engaged during auditory deviance detection.
Collapse
Affiliation(s)
| | - Santiago Collavini
- Studies in Neurosciences and Complex Systems, National Scientific and Technical Research Council, El Cruce Hospital, Arturo Jauretche National University, Argentina.
| | - James Lubell
- Department of Psychology, University of Oslo, Norway.
| | - Anaïs Llorens
- Department of Psychology, University of Oslo, Norway; Department of Neurosurgery, Oslo University Hospital, Rikshospitalet, Norway.
| | | | - Jugoslav Ivanovic
- Department of Neurosurgery, Oslo University Hospital, Rikshospitalet, Norway.
| | - Pål G Larsson
- Department of Neurosurgery, Oslo University Hospital, Rikshospitalet, Norway.
| | - Torstein R Meling
- Department of Neurosurgery, Oslo University Hospital, Rikshospitalet, Norway.
| | | | - Silvia Kochen
- Studies in Neurosciences and Complex Systems, National Scientific and Technical Research Council, El Cruce Hospital, Arturo Jauretche National University, Argentina.
| | - Tor Endestad
- Department of Psychology, University of Oslo, Norway; Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway.
| | - Robert T Knight
- Helen Wills Neuroscience Institute and Department of Psychology, University of California at Berkeley, USA.
| | - Anne-Kristin Solbakk
- Department of Psychology, University of Oslo, Norway; Department of Neurosurgery, Oslo University Hospital, Rikshospitalet, Norway; Department of Neuropsychology, Helgeland Hospital, Mosjøen, Norway.
| |
Collapse
|
12
|
Anders R, Llorens A, Dubarry AS, Trébuchon A, Liégeois-Chauvel C, Alario FX. Cortical Dynamics of Semantic Priming and Interference during Word Production: An Intracerebral Study. J Cogn Neurosci 2019; 31:978-1001. [DOI: 10.1162/jocn_a_01406] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Language production requires that semantic representations are mapped to lexical representations on the basis of the ongoing context to select the appropriate words. This mapping is thought to generate two opposing phenomena, “semantic priming,” where multiple word candidates are activated, and “interference,” where these word activities are differentiated to make a goal-relevant selection. In previous neuroimaging and neurophysiological research, priming and interference have been associated to activity in regions of a left frontotemporal network. Most of such studies relied on recordings that either have high temporal or high spatial resolution, but not both. Here, we employed intracerebral EEG techniques to explore with both high resolutions, the neural activity associated with these phenomena. The data came from nine epileptic patients who were stereotactically implanted for presurgical diagnostics. They performed a cyclic picture-naming task contrasting semantically homogeneous and heterogeneous contexts. Of the 84 brain regions sampled, 39 showed task-evoked activity that was significant and consistent across two patients or more. In nine of these regions, activity was significantly modulated by the semantic manipulation. It was reduced for semantically homogeneous contexts (i.e., priming) in eight of these regions, located in the temporal ventral pathway as well as frontal areas. Conversely, it was increased only in the pre-SMA, notably at an early poststimulus temporal window (200–300 msec) and a preresponse temporal window (700–800 msec). These temporal effects respectively suggest the pre-SMA's role in initial conflict detection (e.g., increased response caution) and in preresponse control. Such roles of the pre-SMA are traditional from a history of neural evidence in simple perceptual tasks, yet are also consistent with recent cognitive lexicosemantic theories that highlight top–down processes in language production. Finally, although no significant semantic modulation was found in the ACC, future intracerebral EEG work should continue to inspect ACC with the pre-SMA.
Collapse
Affiliation(s)
- Royce Anders
- Aix-Marseille University, CNRS, LPC, Marseille, France
| | - Anaïs Llorens
- Aix-Marseille University, CNRS, LPC, Marseille, France
- Oslo University Hospital-Rikshospitalet
| | - Anne-Sophie Dubarry
- Aix-Marseille University, CNRS, LPC, Marseille, France
- Aix-Marseille University, CNRS, LPL, Aix-en-Provence, France
| | - Agnès Trébuchon
- Aix-Marseille University, CNRS, LPC, Marseille, France
- AP-HM, Neurophysiologie Clinique, Marseille, France
- Aix-Marseille University, INSERM, INS, Inst Neurosci Syst, Marseille, France
| | - Catherine Liégeois-Chauvel
- Aix-Marseille University, CNRS, LPC, Marseille, France
- Aix-Marseille University, INSERM, INS, Inst Neurosci Syst, Marseille, France
- Cleveland Clinic Foundation
| | | |
Collapse
|
13
|
Ghighi M, Llorens A, Baroukh B, Chaussain C, Bouchard P, Gosset M. Differences between inflammatory and catabolic mediators of peri-implantitis and periodontitis lesions following initial mechanical therapy: An exploratory study. J Periodontal Res 2017; 53:29-39. [PMID: 28898426 DOI: 10.1111/jre.12483] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND AND OBJECTIVE The aim of this study was to analyze the differences in inflammatory and catabolic mediators expressed in peri-implantitis compared to periodontitis lesions after non-surgical therapy. Peri-implantitis is associated with a faster rate of bone loss when compared with periodontitis, and peri-implant non-surgical therapy is ineffective to cure peri-implantitis. This may be due to persistent inflammation in peri-implantitis tissues after initial mechanical treatment. MATERIAL AND METHODS Eleven patients with peri-implantitis and 10 with severe chronic periodontitis received non-surgical therapy. They were included at re-evaluation (8 weeks) if they presented pocket depth ≥6 mm with bleeding on probing, and the indication for open flap debridement surgery. Connective tissues were harvested during surgery from diseased sites. Healthy gingiva were harvested during third molar extraction in a third group of healthy patients (n=10). Explants were incubated for 24 hours in media culture and the release of cytokines, chemokines, growth factors, osteoprotegerin, receptor activator of nuclear factor kappa-B ligand (RANKL), matrix metalloproteinase and tissue inhibitors of matrix metalloproteinase (TIMP) in the conditioned media was analyzed by an exploratory multiplex immunoassay. When difference was found in the conditioned media, an immunohistochemistry was performed to compare expression in the tissues. RESULTS Connective tissues from non-stabilized peri-implantitis exhibited a distinct cytokine profile compared to periodontitis lesions that did not respond to initial therapy. Indeed, TIMP-2 was significantly increased in media from peri-implantitis (P≤.05). In addition, the in situ expression of TIMP-2, interleukin-10 and RANKL was also significantly increased in peri-implantitis tissues (P≤.05). However, the ratio of RANKL/osteoprotegerin-positive cells did not vary (P≥.05). CONCLUSION This study suggests that peri-implantitis and periodontitis connective tissues exhibit differences in response to non-surgical treatment, which may contribute to a different pattern of disease evolution.
Collapse
Affiliation(s)
- M Ghighi
- EA 2496, U.F.R. of Odontology, Paris Descartes University, Montrouge, France.,Department of Periodontology, U.F.R. of Odontology, Rothschild Hospital, AP-HP, Paris Diderot University, Paris, France
| | - A Llorens
- EA 2496, U.F.R. of Odontology, Paris Descartes University, Montrouge, France
| | - B Baroukh
- EA 2496, U.F.R. of Odontology, Paris Descartes University, Montrouge, France
| | - C Chaussain
- EA 2496, U.F.R. of Odontology, Paris Descartes University, Montrouge, France.,Department of Odontology, Bretonneau Hospital, AP-HP, Hôpitaux Universitaires Paris Nord Val de Seine (Bretonneau), Paris, France
| | - P Bouchard
- EA 2496, U.F.R. of Odontology, Paris Descartes University, Montrouge, France.,Department of Periodontology, U.F.R. of Odontology, Rothschild Hospital, AP-HP, Paris Diderot University, Paris, France
| | - M Gosset
- EA 2496, U.F.R. of Odontology, Paris Descartes University, Montrouge, France.,Department of Periodontology, Charles Foix Hospital, AP-HP, Hôpitaux Universitaires La Pitié Salpétrière - Charles Foix, Paris, France
| |
Collapse
|
14
|
Llorens A, Dubarry AS, Trébuchon A, Chauvel P, Alario FX, Liégeois-Chauvel C. Contextual modulation of hippocampal activity during picture naming. Brain Lang 2016; 159:92-101. [PMID: 27380274 DOI: 10.1016/j.bandl.2016.05.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 05/17/2016] [Accepted: 05/24/2016] [Indexed: 06/06/2023]
Abstract
Picture naming is a standard task used to probe language processes in healthy and impaired speakers. It recruits a broad neural network of language related areas, among which the hippocampus is rarely included. However, the hippocampus could play a role during picture naming, subtending, for example, implicit learning of the links between pictured objects and their names. To test this hypothesis, we recorded hippocampal activity during plain picture naming, without memorization requirement; we further assessed whether this activity was modulated by contextual factors such as repetition priming and semantic interference. Local field potentials recorded from intracerebral electrodes implanted in the healthy hippocampi of epileptic patients revealed a specific and reliable pattern of activity, markedly modulated by repetition priming and semantic context. These results indicate that the hippocampus is recruited during picture naming, presumably in relation to implicit learning, with contextual factors promoting differential hippocampal processes, possibly subtended by different sub-circuitries.
Collapse
Affiliation(s)
- A Llorens
- Aix Marseille Univ, Inserm, Institut des Neurosciences des Systemes, Marseille, France; Aix Marseille Univ, CNRS, UMR7290, LPC, Marseille, France
| | - A-S Dubarry
- Aix Marseille Univ, Inserm, Institut des Neurosciences des Systemes, Marseille, France; Aix Marseille Univ, CNRS, UMR7290, LPC, Marseille, France
| | - A Trébuchon
- Aix Marseille Univ, Inserm, Institut des Neurosciences des Systemes, Marseille, France; AP-HM, Neurophysiologie Clinique, Marseille, France
| | - P Chauvel
- Aix Marseille Univ, Inserm, Institut des Neurosciences des Systemes, Marseille, France; AP-HM, Neurophysiologie Clinique, Marseille, France
| | - F-X Alario
- Aix Marseille Univ, CNRS, UMR7290, LPC, Marseille, France
| | - C Liégeois-Chauvel
- Aix Marseille Univ, Inserm, Institut des Neurosciences des Systemes, Marseille, France.
| |
Collapse
|
15
|
Fraile L, Segalés J, Ticó G, López-Soria S, Valero O, Nofrarías M, Huerta E, Llorens A, López-Jiménez R, Pérez D, Sibila M. Virological and serological characterization of vaccinated and non-vaccinated piglet subpopulations coming from vaccinated and non-vaccinated sows. Prev Vet Med 2015; 119:153-61. [PMID: 25748003 DOI: 10.1016/j.prevetmed.2015.02.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 02/12/2015] [Accepted: 02/16/2015] [Indexed: 11/17/2022]
Abstract
The present study describes the virological and serological profiles of PCV2 vaccinated (V) and non-vaccinated (NV) piglet subpopulations coming from V and NV sows in a PCV2 subclinically infected farm. Four hundred seventy-six piglets born from V or NV sows were further subdivided in a total of four groups: NV sows-NV pigs (NV-NV), NV sows-V pigs (NV-V); V sows-NV pigs (V-NV) and V sows-V pigs (V-V). Seventy-five pigs were randomly selected at the beginning of the trial from each group and they were bled at 4, 8, 12, 16, 21 and 25 weeks of age. All animals included in the trial were weighed at 4 and 25 weeks of age and their average daily weight gain (ADWG) was calculated. Serum samples obtained at different time points were used to assess PCV2 infection (viremia) and the level of antibodies by means of immunoperoxidase monolayer assay (IPMA) against this pathogen. IPMA titers (classified in high, medium or low) and PCR results (positive or negative) were analyzed using a multiple correspondence and K-means cluster analysis. According to these tests, animals included in the study were classified into the following four clusters: (1) 93 piglets that were viremic mainly from 12 to 25 weeks of age and with PCV2 antibody titers increasing over time; (2) 75 piglets with late PCV2 infection and seroconversion (later than 16 weeks of age); (3) 26 piglets with high but decreasing PCV2 antibody titers and low percentages of PCV2 PCR positive serum samples; and (4) 105 piglets with medium and high IPMA titers throughout the trial and sporadic PCR positive samples. The defined subpopulations of piglets were observed in all experimental groups (NV-NV, NV-V, V-NV and V-V) although in variable percentages. Thus, animals from clusters 1 and 2 belonged mainly to the NV-NV and V-NV groups and animals from clusters 3 and 4 were distributed mainly into the NV-V and V-V groups. Finally, the ADWG of pigs belonging to clusters 3 and 4 was significantly higher (p=0.02) than that of pigs belonging to clusters 1 and 2. Within each cluster, no statistically significant differences were found in ADWG between treatment groups.
Collapse
Affiliation(s)
- L Fraile
- Departament de Producció Animal, ETSEA, Universitat de Lleida, 25198 Lleida, Spain.
| | - J Segalés
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain; Departament de Sanitat i d'Anatomia Animals, Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - G Ticó
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - S López-Soria
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - O Valero
- Servei d'Estadística Aplicada, Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - M Nofrarías
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - E Huerta
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - A Llorens
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - R López-Jiménez
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - D Pérez
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| | - M Sibila
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallés), Spain
| |
Collapse
|
16
|
Llorens A, Trébuchon A, Riès S, Liégeois-Chauvel C, Alario FX. How familiarization and repetition modulate the picture naming network. Brain Lang 2014; 133:47-58. [PMID: 24785306 PMCID: PMC4053586 DOI: 10.1016/j.bandl.2014.03.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 03/18/2014] [Accepted: 03/28/2014] [Indexed: 05/04/2023]
Abstract
A common strategy to reveal the components of the speech production network is to use psycholinguistic manipulations previously tested in behavioral protocols. This often disregards how implementation aspects that are nonessential for interpreting behavior may affect the neural response. We compared the electrophysiological (EEG) signature of two popular picture naming protocols involving either unfamiliar pictures without repetitions or repeated familiar pictures. We observed significant semantic interference effects in behavior but not in the EEG, contrary to some previous findings. Remarkably, the two protocols elicited clearly distinct EEG responses. These were not due to naming latency differences nor did they reflect a homogeneous modulation of amplitude over the trial time-window. The effect of protocol is attributed to the familiarization induced by the first encounter with the materials. Picture naming processes can be substantially modulated by specific protocol requirements controlled by familiarity and, to a much lesser degree, the repetition of materials.
Collapse
Affiliation(s)
- Anaïs Llorens
- Institut des Neurosciences des Systèmes, Aix-Marseille Université, INSERM UMR 1106, France; Laboratoire de Psychologie Cognitive, Aix-Marseille Université, CNRS UMR 7290, France.
| | - Agnès Trébuchon
- Institut des Neurosciences des Systèmes, Aix-Marseille Université, INSERM UMR 1106, France
| | - Stéphanie Riès
- Laboratoire de Psychologie Cognitive, Aix-Marseille Université, CNRS UMR 7290, France; Helen Wills Neuroscience Institute, University of California, Berkeley, United States
| | | | - F-Xavier Alario
- Laboratoire de Psychologie Cognitive, Aix-Marseille Université, CNRS UMR 7290, France
| |
Collapse
|
17
|
Llorens A, Trébuchon A, Liégeois-Chauvel C, Alario FX. Intra-cranial recordings of brain activity during language production. Front Psychol 2011; 2:375. [PMID: 22207857 PMCID: PMC3246222 DOI: 10.3389/fpsyg.2011.00375] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 11/28/2011] [Indexed: 02/06/2023] Open
Abstract
Recent findings in the neurophysiology of language production have provided a detailed description of the brain network underlying this behavior, as well as some indications about the timing of operations. Despite their invaluable utility, these data generally suffer from limitations either in terms of temporal resolution, or in terms of spatial localization. In addition, studying the neural basis of speech is complicated by the presence of articulation artifacts such as electro-myographic activity that interferes with the neural signal. These difficulties are virtually absent in a powerful albeit much less frequent methodology, namely the recording of intra-cranial brain activity (intra-cranial electroencephalography). Such recordings are only possible under very specific clinical circumstances requiring functional mapping before brain surgery, most notably in patients that suffer from pharmaco-resistant epilepsy. Here we review the research conducted with this methodology in the field of language production, with explicit consideration of its advantages and drawbacks. The available evidence is shown to be diverse, both in terms of the tasks and the cognitive processes tested and in terms of the brain localizations being studied. Still, the review provides valuable information for characterizing the dynamics of the neural events occurring in the language production network. Following modality specific activities (in auditory or visual cortices), there is a convergence of activity in superior temporal sulcus, which is a plausible neural correlate of phonological encoding processes. Later, between 500 and 800 ms, inferior frontal gyrus (around Broca's area) is involved. Peri-rolandic areas are recruited in the two modalities relatively early (200-500 ms window), suggesting a very early involvement of (pre-) motor processes. We discuss how some of these findings may be at odds with conclusions drawn from available meta-analysis of language production studies.
Collapse
Affiliation(s)
- Anaïs Llorens
- INSERM UMR 751, Aix-Marseille Université Marseille, France
| | | | | | | |
Collapse
|
18
|
Martínez-Guinó L, Kekarainen T, Maldonado J, Aramouni M, Llorens A, Segalés J. Torque teno sus virus (TTV) detection in aborted and slaughterhouse collected foetuses. Theriogenology 2010; 74:277-81. [DOI: 10.1016/j.theriogenology.2010.02.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 02/04/2010] [Accepted: 02/05/2010] [Indexed: 10/19/2022]
|
19
|
Fouz B, Llorens A, Valiente E, Amaro C. A comparative epizootiologic study of the two fish-pathogenic serovars of Vibrio vulnificus biotype 2. J Fish Dis 2010; 33:383-390. [PMID: 20158583 DOI: 10.1111/j.1365-2761.2009.01130.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Vibrio vulnificus biotype 2 is subdivided into two main serovars, serovar E, able to infect fish and humans, and serovar A, only virulent for fish. Serovar E emerged in 1976 as the causative agent of a haemorrhagic septicaemia (warm-water vibriosis) affecting eels cultured in brackish water. Serovar A emerged in 2000 in freshwater-cultured eels vaccinated against serovar E, causing warm-water vibriosis with fish showing a haemorrhagic intestine as the main differential sign. The aim of the present work was to compare the disease caused by both serovars in terms of transmission routes, portals of entry and host range. Results of bath, patch-contact and oral-anal challenges demonstrated that both serovars spread through water and infect healthy eels, serovar A entering mainly by the anus and serovar E by the gills. The course of the disease under laboratory conditions was similar for both serovars in terms of transmission and dependence of degree of virulence on water parameters (temperature and salinity). However, the decrease in degree of virulence in fresh water was significantly greater in serovar E than in serovar A. Finally, both serovars proved pathogenic for tilapia, sea bass and rainbow trout, but not for sea bream, with significant differences in degree of virulence only in rainbow trout. In conclusion, serovar A seems to represent a new antigenic form of V. vulnificus biotype 2 with an unusual portal of entry and is better adapted to fresh water than serovar E.
Collapse
Affiliation(s)
- B Fouz
- Department of Microbiology and Ecology, Faculty of Biology, University of Valencia, Valencia, Spain.
| | | | | | | |
Collapse
|
20
|
Gallina S, Barranco-Piedra S, Torres-Lagares D, Baroukh B, Llorens A, Gutiérrez-Pérez JL, Saffar JL, Cherruau M, Lesclous P. Estrogen Withdrawal Transiently Increased Bone Turnover Without Affecting the Bone Balance Along the Tooth Socket in Rats. J Periodontol 2009; 80:2035-44. [DOI: 10.1902/jop.2009.090297] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
21
|
Sibila M, Martínez-Guinó L, Huerta E, Llorens A, Mora M, Grau-Roma L, Kekarainen T, Segalés J. Swine torque teno virus (TTV) infection and excretion dynamics in conventional pig farms. Vet Microbiol 2009; 139:213-8. [PMID: 19559548 DOI: 10.1016/j.vetmic.2009.05.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 05/15/2009] [Accepted: 05/28/2009] [Indexed: 11/27/2022]
Abstract
Torque teno virus (TTV) is a non-enveloped, single-stranded DNA (ssDNA) virus infecting human and non-primate species. Two genogroups of TTV (TTV1 and TTV2) have been described in swine so far. In the present study, TTV1 and TTV2 prevalences in serum, and nasal as well as rectal swabs of 55 randomly selected piglets from seven Spanish multi-site farms, were monitored from 1 to 15 weeks of age. Also, blood from their dams (n=41) were taken at 1 week post-farrowing. Samples were tested by means of two TTV genogroup specific PCRs. Although prevalence of TTV1 and TTV2 in sows was relatively high (54% and 32%, respectively), it was not directly associated to their prevalence in the offspring. Percentage of viremic pigs for both TTV genogroups followed similar dynamics, increasing progressively over time, with the highest rate of detection at 11 weeks of age for TTV1 and at 15 weeks for TTV2. Forty-two (76%) and 33 (60%) of the 55 studied pigs were TTV1 and TTV2 PCR positive in serum, respectively, in more than one sampling time. TTV1 and TTV2 viremia lasted in a number of animals up to 15 and 8 weeks, respectively. Co-infection with both TTV genogroups in serum was detected at all sampling points, but at 1 week of age. On the contrary, there were animals PCR negative to both genogroups in serum at all sampling times but at 15 weeks of age. During the study period, TTV1 and TTV2 nasal shedding increased also over time and faecal excretion was intermittent and of low percentage (<20%). In conclusion, the present study describes for the first time the infection dynamics of TTV1 and TTV2 as well as the nasal and faecal excretion throughout the life of pigs from conventional, multi-site farms. Moreover, results indicate that both swine TTV genogroups are able to establish persistent infections in a number of pigs.
Collapse
Affiliation(s)
- M Sibila
- Centre de Recerca en Sanitat Animal, UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Valiente E, Padrós F, Lamas J, Llorens A, Amaro C. Microbial and histopathological study of the vibriosis caused by Vibrio vulnificus serovar E in eels: The metalloprotease Vvp is not an essential lesional factor. Microb Pathog 2008; 45:386-93. [DOI: 10.1016/j.micpath.2008.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Revised: 09/01/2008] [Accepted: 09/12/2008] [Indexed: 01/22/2023]
|
23
|
Diaz-Ramos A, Llorens A, Luque T, Lopez-Alemany R. ID: 287 An antibody anti-alpha-enolase, MAb 11G1, inhibits myogenesis in vitro and in vivo. J Thromb Haemost 2006. [DOI: 10.1111/j.1538-7836.2006.00287.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
24
|
Llorens A, Hinojo MJ, Mateo R, Medina A, Valle-Algarra FM, González-Jaén MT, Jiménez M. Variability and characterization of mycotoxin-producing Fusarium spp isolates by PCR-RFLP analysis of the IGS-rDNA region. Antonie Van Leeuwenhoek 2006; 89:465-78. [PMID: 16779639 DOI: 10.1007/s10482-005-9045-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/21/2005] [Indexed: 10/24/2022]
Abstract
In the present report, a total of 75 Fusarium spp isolates (35 of the Gibberella fujikuroi species complex, 26 of F. oxysporum, 7 of F. graminearum, 5 of F. culmorum, 1 of F. cerealis, and 1 of F. poae) from different hosts were characterized morphologically, physiologically and genetically. Morphological characterization was performed according to macroscopic and microscopic aspects. Physiological characterization was based on their ability to produce fumonisin B1 (FB1), fumonisin B2 (FB2), zearalenone (ZEA) and type B trichothecenes (deoxynivalenol, nivalenol and 3-acetyldeoxynivalenol). FB1, FB2, and ZEA were determined by liquid chromatography and trichothecenes by gas chromatography. Molecular characterization of isolates was carried out using an optimized and simple method for isolation of DNA from filamentous fungi and polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) of the intergenic spacer region (IGS) of the rDNA. The results indicated that G. fujikuroi complex isolates can be divided into low and high fumonisin producers. The haplotypes obtained with HhaI, EcoRI, AluI, PstI and XhoI enzymes provided very characteristic groupings of G. fujikuroi isolates as a function of host type and fumonisin producing capacity. F. graminearum, F. culmorum and F. cerealis isolates were high ZEA and type B trichothecene producers, while F. oxysporum and the G. fujikuroi complex isolates did not show this ability. The haplotypes obtained with CfoI, AluI, HapII, XhoI, EcoRI and PstI enzymes permitted to discern these five Fusarium species and G. fujikuroi complex isolates but the restriction patterns of the IGS region did not show any relationship with the geographic origin of isolates.
Collapse
Affiliation(s)
- A Llorens
- Departamento de Microbiología y Ecología, Universidad de Valencia, Dr. Moliner 50, E-46100, Burjassot, Valencia, Spain
| | | | | | | | | | | | | |
Collapse
|
25
|
Llorens A, Hinojo MJ, Mateo R, González-Jaén MT, Valle-Algarra FM, Logrieco A, Jiménez M. Characterization of Fusarium spp. isolates by PCR-RFLP analysis of the intergenic spacer region of the rRNA gene (rDNA). Int J Food Microbiol 2005; 106:297-306. [PMID: 16246443 DOI: 10.1016/j.ijfoodmicro.2005.09.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2004] [Revised: 08/16/2005] [Accepted: 09/02/2005] [Indexed: 11/23/2022]
Abstract
In the present study, 44 Fusarium spp. isolates (5 Fusarium culmorum, 7 Fusarium graminearum, 1 Fusarium cerealis, 1 Fusarium poae, 26 Fusarium oxysporum, and 4 Gibberella fujikuroi species complex) were characterized morphologically, physiologically and genetically. All except one (Dutch Collection: CBS 620.72) were isolated from different hosts grown in various Spanish localizations. Morphological characterization was made according to macroscopic and microscopic aspects. Physiological characterization was based on their ability to produce zearalenone (ZEA) and type B trichothecenes (deoxynivalenol, nivalenol and 3-acetyldeoxynivalenol). ZEA was determined by liquid chromatography and trichothecenes by gas chromatography. Confirmation was carried out by liquid chromatography-ion trap-mass spectrometry (ZEA) or gas chromatography-mass spectrometry (trichothecenes). Molecular characterization of isolates was performed using an optimized, simple and low-cost method for isolation of DNA from filamentous fungi and polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) of the intergenic spacer region (IGS) of the rRNA gene (rDNA). The results indicate that F. graminearum, F. culmorum and F. cerealis isolates were high ZEA and type B trichothecene producers, the F. poae isolate produced very low level of nivalenol while F. oxysporum and the G. fujikuroi complex isolates did not show this ability. Restriction patterns of the IGS region did not show any relationship with the host, geographic origin of the isolate and mycotoxin-producing capacity. However, the haplotypes obtained with six restriction enzymes (CfoI, AluI, HapII, XhoI, EcoRI and PstI) permitted to discern the six assayed Fusarium species. Therefore, this is a rapid and suitable methodology that allows closely related strains to group and to estimate the genetic relationships between the groups.
Collapse
Affiliation(s)
- A Llorens
- Departamento Microbiologia y Ecología, Facultad de Biología, Universidad de Valencia, Dr. Moliner 50, E-46100 Burjassot, Valencia, Spain
| | | | | | | | | | | | | |
Collapse
|
26
|
Vermelin L, Baroukh B, Llorens A, Saffar JL. Effects of essential fatty acid deficiency on periodontal tissue adaptation to spontaneous tooth migration. Calcif Tissue Int 2005; 77:30-6. [PMID: 16007482 DOI: 10.1007/s00223-004-0248-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2004] [Accepted: 01/21/2005] [Indexed: 11/24/2022]
Abstract
Essential fatty acids (EFAs) play a significant role in bone metabolism. Herein we studied the adaptation of alveolar bone to physiologic tooth drift in young rats deprived of essential fatty acids from birth. Reductions in femur size and trabecular bone volume reflected body growth impairment. Along the alveolar wall, osteoclastic resorption and bone formation were depressed, disrupting the adaptive deformation of the tooth socket to ongoing migration. As a result, the periodontal ligament narrowed considerably, and further adaptation was achieved through root resorption. Essential fatty acid deficiency (EFAD), did not affect precursor recruitment or differentiation in the periodontal ligament (PDL), but caused redistribution of nonspecific-esterase (NSE)-positive osteoclast precursors and tartrate-resistant acid phosphatase (TRAP)-positive pre-osteoclasts between the bone compartment (which was depleted) and the root compartment (which was enriched). EFAD had also a marked effect on the PDL vasculature; the number of vessels was reduced, whereas their size was markedly increased. As a whole, our results show that EFAD disturbs alveolar bone adaptation to drift, but that a reaction (detrimental to root integrity) prevents root collision with the bone surface, thereby preserving the PDL as a source of precursor cells for bone and cementum homeostasis. Moreover, our results confirm that although alveolar bone resorption is arachidonic acid-dependent, the factors activating root resorption are different.
Collapse
Affiliation(s)
- L Vermelin
- Laboratoire de Biologie et Physiopathologie Crânio-Faciales EA 2496, Faculté de Chirurgie Dentaire, Université René Descartes Paris-5, 1 rue M. Arnoux, 92120 Montrouge, France
| | | | | | | |
Collapse
|
27
|
Llorens A, Mateo R, Hinojo MJ, Valle-Algarra FM, Jiménez M. Influence of environmental factors on the biosynthesis of type B trichothecenes by isolates of Fusarium spp. from Spanish crops. Int J Food Microbiol 2004; 94:43-54. [PMID: 15172484 DOI: 10.1016/j.ijfoodmicro.2003.12.017] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2003] [Revised: 11/27/2003] [Accepted: 12/22/2003] [Indexed: 11/24/2022]
Abstract
Various species of Fusarium can produce trichothecene mycotoxins that contaminate food commodities and can represent a risk for human and animal health. In this paper, a full factorial design was applied to study the influence of incubation temperature, water activity (a(w)) and type of isolate on the production of deoxynivalenol (DON), nivalenol (NIV) and 3-acetyldeoxynivalenol (3-AcDON) in corn kernel cultures by three isolates of Fusarium graminearum and three isolates of Fusarium culmorum from crops grown in Spain. The tested temperatures were 15, 20, 28 and 32 degrees C. The a(w)-values were 0.960, 0.970 and 0.980. Moisture of cultures (within the studied range) did not affect significantly production of trichothecenes; however, the temperature affected significantly mycotoxin production and the optimal values were 28, 20 and 15 degrees C for DON, NIV and 3-AcDON, respectively. Four additional isolates of F. graminearum and two additional isolates of F. culmorum were examined for production of these mycotoxins at the optimal temperatures. Of the seven isolates of F. graminearum, four produced DON (0.88-3.97 microg/g), seven produced NIV (1.53-124 microg/g), and three produced 3-AcDON (0.65-10.6 microg/g). Of the five isolates of F. culmorum, four produced DON (1.20-4.93 microg/g), four produced NIV (6.94-701 microg/g), and four produced 3-AcDON (0.83-7.70 microg/g). Practically all isolates seem to belong to the NIV-chemotype. This is the first study done with regard to interaction between strain and ecological variables on type B trichothecene production by isolates of these two species from crops grown in Spain.
Collapse
Affiliation(s)
- A Llorens
- Dpto. Microbiología y Ecología, Facultad de Biología, Universidad de Valencia. Dr. Moliner 50, E-46100, Burjasot, Valencia, Spain
| | | | | | | | | |
Collapse
|
28
|
Adam C, Llorens A, Baroukh B, Cherruau M, Saffar JL. Effects of Capsaicin-Induced Sensory Denervation on Osteoclastic Resorption in Adult Rats. Exp Physiol 2004. [DOI: 10.1111/j.1469-445x.2000.01930.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
29
|
Mateo JJ, Mateo R, Hinojo MJ, Llorens A, Jiménez M. Liquid chromatographic determination of toxigenic secondary metabolites produced by Fusarium strains. J Chromatogr A 2002; 955:245-56. [PMID: 12075928 DOI: 10.1016/s0021-9673(02)00214-5] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Various liquid chromatographic methods used in the analysis of mycotoxins (zearalenone, trichothecenes and fumonisins) produced by Fusarium species were compared in this work. The results demonstrate the suitability of modern clean-up procedures employing multifunctional MycoSep and immunoaffinity columns although these methods are more expensive than conventional methodologies for clean-up. HPLC with both fluorescence and photodiode array detection is a suitable technique for the analysis of toxic secondary metabolites produced by Fusarium species; different derivatisation strategies have been studied to improve the sensitivity of the technique because of the low concentration of these metabolites in contaminated food. The utility of the proposed methodology was assessed in cereal cultures of various Fusarium strains.
Collapse
Affiliation(s)
- J J Mateo
- University of Valencia, Department of Microbiology and Ecology, Burjassot, Spain.
| | | | | | | | | |
Collapse
|
30
|
Llorens A, Mateo R, Mateo JJ, Jiménez M. Comparison of extraction and clean-up procedures for analysis of zearalenone in corn, rice and wheat grains by high-performance liquid chromatography with photodiode array and fluorescence detection. Food Addit Contam 2002; 19:272-81. [PMID: 11834077 DOI: 10.1080/02652030110081173] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The aim of this work was the optimization of some procedures usually used in the analysis of zearalenone (ZEA) in corn and other cereals by high-performance liquid chromatography (HPLC) with photodiode array and/or fluorescence detection. The comparison of five extraction solvents is presented. Three solid-phase extraction cartridges (C-18, silica, Florisil) and immuno-affinity columns were also compared to obtain the best recovery of the mycotoxin with the minimal presence of co-extractives in the chromatograms. Mixtures of methanol-1% aqueous NaCl (80.20 or 60:40 v/v) were the best extraction solvents. Florisil provided higher recovery of ZEA than C-18, and silica proved unsuitable. The immuno-affinity column was very efficient in cleaning the extracts, but its sample capacity was lower than that of SPE columns due to saturation. The mobile phase (methanol-water 80:20 v/v) gave a low retention time for ZEA (approximately 5 min), high sensitivity and acceptable separation between this mycotoxin and alpha-zearalenol. The optimized protocol is straightforward, provides high ZEA recoveries in spiked corn (mean 102.4%), has an acceptable sensitivity and has a lack of interference with fluorescence detection (detection limit 4 ng ZEA g(-1) corn). The photodiode array detector was useful, except at very low ZEA levels, to confirm the identity of the mycotoxin. The method was applied to search for ZEA accumulation in corn, wheat and rice grains inoculated with selected strains of Fusarium graminearum, F. oxysporum and method was applied to search for ZEA accumulation in corn, wheat and rice grains inoculated with selected strains of Fusarium graminearum, F. oxysporum and F. culmorum.
Collapse
Affiliation(s)
- A Llorens
- Departamento de Microbiología y Ecología, Facultad de Biología, Universitat de Valencia, Burjassot, Spain
| | | | | | | |
Collapse
|
31
|
Abstract
Various analytical methods used in the analysis of type B trichothecenes (deoxynivalenol, nivalenol, 3- and 15-acetyldeoxynivalenol) in cereals were compared and optimised in this work. These methods use either GC-electron-capture detection (ECD) of trimethylsilyl, trifluoroacetyl and heptafluorobutyryl derivatives or HPLC with UV or photodiode array detection of analytes. A new HPLC procedure using fluorescence detection prior derivatisation with coumarin-3-carbonyl chloride has been also tested. Five extraction solvents and two solid-phase extraction cartridges (silica, Florisil) plus a especial clean-up column (MycoSep 225) were compared in order to obtain the best recovery of the mycotoxins with minimal presence of coextractives in the chromatograms. The chosen extraction solvent was a mixture of acetonitrile-water (84:16, v/v). The MycoSep 225 column was chosen as the best alternative for clean-up of grain samples. For GC-ECD analysis, derivatisation of analytes with heptafluorobutyric anhydride prior the final determination was chosen as the most suitable procedure. HPLC-photodiode array (at 221 nm) analysis was more suitable for determination of type B trichothecenes than HPLC of the fluorescent coumarin-3-carbonyl derivatives. Recoveries obtained in spiked corn, rice and wheat are reported. The utility of the proposed methodology was assayed in cereal cultures of various Fusarium strains.
Collapse
Affiliation(s)
- J J Mateo
- Dpto. Microbiología, Facultad CC Biológicas, Universidad de Valencia, Burjasot, Spain.
| | | | | | | |
Collapse
|
32
|
Abstract
We previously reported that mast cells accumulate in the tibia bone marrow of ovariectomized (OVX) rats. In this study, the timing of mast cell accumulation and osteoclast generation were compared to determine whether or not mast cell accumulation preceded osteoclast recruitment after ovariectomy. This may be significant because of the number of cytokines released by mast cells that are potentially active on resorption. Sprague-Dawley rats (120) aged 12 weeks were OVX or sham-operated, and killed on days 4, 7, 14, 28, and 56 postsurgery. Ten additional intact rats were used as baseline controls. Ovariectomy was confirmed by a sharp and sustained fall in serum estradiol. The loss in trabecular bone volume (BV/TV) began on day 7, reaching 80% on day 56 (P < 0.001 vs baseline controls). The number of osteoclasts (N.OC/TBPm) increased in the OVX rats between days 4 and 7 (+130%; P < 0.001), and continued rising to day 28. During the next month, it decreased greatly (-63%, P < 0.001 on day 56 vs day 28). In the sham-treated rats, few mast cells were scattered in the bone marrow (1.9 cells/mm2 in the baseline controls). Their number fluctuated during the experimental period, but at each time-point it was lower than in the OVX rats. They were predominantly (90%) of the mucosal subtype. In the OVX rats, their number doubled between days 4 and 14 (P < 0.001), reached 8.6 cells/mm2 on day 28 (a 5.4-fold increase compared with day 4 OVX rats), and plateaued for the next 4 weeks. OVX had no effects on mast cell subtypes. In conclusion, mast cell accumulation and osteoclast differentiation are precocious and concomitant; this does not support a direct role for mast cells in osteoclast recruitment. Rather, the two cell populations may derive from a common precursor or be targeted simultaneously by estrogen depletion through common stimulator(s). Mast cell hyperplasia appears to be a significant, and usually unknown, manifestation of ovariectomy in the bone marrow environment.
Collapse
Affiliation(s)
- P Lesclous
- Laboratoire de Biologie et Physiopathologie Crânio-Faciales, Faculté de Chirurgie Dentaire Université René Descartes (Paris-V), Montrouge, France
| | | | | | | |
Collapse
|
33
|
Adam C, Llorens A, Baroukh B, Cherruau M, Saffar JL. Effects of capsaicin-induced sensory denervation on osteoclastic resorption in adult rats. Exp Physiol 2000; 85:62-6. [PMID: 10662894 DOI: 10.1017/s0958067000019308] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Many recent findings suggest that the nervous system has efferent effects on bone. A putative role of the sensory innervation has been assessed by using a synchronised rat model of bone resorption after treating adult animals with the neurotoxin capsaicin. Fourteen days after capsaicin treatment (50 mg kg-1) the right maxillary molars were extracted to activate a wave of resorption along the mandibular cortex. The rats were killed 4 days later (i.e. at the peak of resorption in this model), and their right mandibles were processed for histometric evaluation of resorption along the cortex and of calcitonin gene-related peptide (CGRP)- and substance P (SP)-immunoreactive (IR) fibres in the dental pulp. CGRP-IR and SP-IR fibres were significantly reduced in numbers by the capsaicin treatment (by 58 and 49%, respectively), confirming the success of sensory denervation. The resorption surface was significantly reduced (P < 0.005) versus the sham-treated animals. Although the size of the osteoclast population recruited in the site was not modified, the number of actively resorbing osteoclasts was significantly reduced (P < 0.03). However, the activity of the resorbing cells was not modified. Non-specific esterase-positive osteoclast precursors were also significantly few after capsaicin treatment. These data show that the sensory nervous system is involved in the control of bone resorption at two different levels: (1) in the recruitment of osteoclast precursors, and (2) in regulating the access of recruited cells to the bone surface.
Collapse
Affiliation(s)
- C Adam
- Laboratoire de Biologie et Physiopathologie Crânio-Faciales, Groupe Physiopathologie Osseuse, Faculte de Chirurgie-Dentaire, Universite Rene Descartes (Paris V), 1 rue Maurice Arnoux, 92120 Montrouge, France
| | | | | | | | | |
Collapse
|
34
|
Vinyals A, Alía P, Llorens A, Adrover M, Gonzalez-Garrigues M, Masramon L, Peinado MA, Fabra A. Detection of differentially expressed gelatinase A in metastatic and non-metastatic subpopulations of tumor cells by target RNA arbitrarily primed polymerase chain reaction (TRAP-PCR). Clin Exp Metastasis 1998; 16:603-11. [PMID: 9932607 DOI: 10.1023/a:1006584910365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have developed a novel procedure called Targeted RNA AP-PCR (TRAP-PCR) to quantitatively measure specific mRNA expression. The target mRNA is reverse transcribed using a specific primer and PCR is performed under low stringency conditions to generate a rich fingerprint-type band pattern. In this situation multiple sequences are coamplified with the targeted sequence. The amplification is carried out in a competitive fashion and is, in consequence, quantitative. We have applied this technique to determine Gelatinase A (Gel A) mRNA expression in the MXT mouse mammary carcinoma system. TRAP-PCR analysis using primers for Gel A produced a reproducible fingerprint including one major band whose identity was confirmed to be Gel A cDNA. Highly metastatic MXT subclones show an increased Gel A expression. Results were confirmed by Northern blot and protein activity (gelatin zymography). TRAP-PCR is a simple, sensitive and specific technique to comparatively quantify mRNA expression and requires less template than conventional methods.
Collapse
Affiliation(s)
- A Vinyals
- Institut de Recerca Oncològica, Cancer & Metastasis Department, Hospital Duran Reynals, L'Hospitalet de Llobregat, Barcelona, Spain
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Llorens A, Rodrigo I, López-Barcons L, Gonzalez-Garrigues M, Lozano E, Vinyals A, Quintanilla M, Cano A, Fabra A. Down-regulation of E-cadherin in mouse skin carcinoma cells enhances a migratory and invasive phenotype linked to matrix metalloproteinase-9 gelatinase expression. J Transl Med 1998; 78:1131-42. [PMID: 9759657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
To assess the role of gelatinases in mouse skin tumor progression and their link to the expression of E-cadherin (E-CD), the cell-cell adhesion protein, we used the highly metastatic squamous HaCa4 cell line and several HaCa4-derived clones obtained by transfection of the mouse E-CD cDNA. Expression of matrix metalloproteinase-9 (MMP-9) mRNA and protein activity were present in E-CD (-) HaCa4 and control clones in culture, but they were strongly diminished in E-CD (+) clones (E24 and E62) at subconfluence. To explore the suppressive effect of the cell-cell contacts mediated by E-CD on MMP-9 expression, we introduced a plasmid encoding mouse E-CD antisense cDNA into the E24 cell clone. The transfectant P1-clones obtained with reduced or absent E-CD expression showed increased levels of MMP-9 gelatinase, motility in vitro, and metastatic potential in vivo. Expression of MMP-9 in the various cell clones was also negatively modulated by cell density, but this effect was much stronger in E-CD (+) cells, despite the fact that all of the cell clones analyzed maintained the expression of P-cadherin and made cell-cell contacts at high cell density. Our results indicate that in this cell system, the E-CD-mediated cell-cell contacts are involved in the down-regulation of MMP-9 expression. Thus, the loss of E-CD triggers a migratory and invasive phenotype in mouse squamous carcinoma cells.
Collapse
Affiliation(s)
- A Llorens
- Department of Cancer and Metastasis, Institut de Recerca Oncològica, Barcelona, Spain
| | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Mollinedo F, Nakajima M, Llorens A, Barbosa E, Callejo S, Gajate C, Fabra A. Major co-localization of the extracellular-matrix degradative enzymes heparanase and gelatinase in tertiary granules of human neutrophils. Biochem J 1997; 327 ( Pt 3):917-23. [PMID: 9581574 PMCID: PMC1218875 DOI: 10.1042/bj3270917] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The expression of cell-surface adhesion proteins and the release of extracellular-matrix degradative enzymes constitute crucial processes for the attachment of neutrophils to the endothelium and for the subsequent extravasation of these cells through the endothelial layer. We have analysed in resting human neutrophils the subcellular localization of heparanase, a heparan-sulphate-degrading endoglycosidase that can degrade basement-membrane components, thereby facilitating neutrophil passage into the tissue during an inflammatory reaction. By subcellular fractionation of postnuclear supernatants from resting human neutrophils on continuous sucrose gradients, we have found that heparanase activity was mainly located in gelatinase-containing tertiary granules. Using a specific antibody, the 96-kDa heparanase protein was further located in the gelatinase-rich subcellular fractions. Following immunoblotting and immunoprecipitation analysis in the distinct subcellular fractions, we also found co-localization of heparanase and Mo1 (CD11b/CD18), a leucocyte integrin involved in the attachment of neutrophils to the endothelium, in the fractions enriched in gelatinase-containing tertiary granules. Treatment of human neutrophils with tumour necrosis factor or granulocyte/macrophage colony-stimulating factor induced an increase in the CD11b/CD18 cell-surface expression, as well as the release of both gelatinase (matrix metalloproteinase-9) and heparanase, but not of other granule markers, indicating a major co-localization of gelatinase, heparanase and CD11b/CD18 in the same organelle. Furthermore, confocal laser scanning microscopy using specific antibodies against gelatinase and heparanase revealed a major co-localization of both enzymes in intracellular cytoplasmic granules. The major localization of heparanase and CD11b/CD18 in the gelatinase-containing tertiary granule supports the notion that mobilization of this organelle can regulate extravasation of human neutrophils.
Collapse
Affiliation(s)
- F Mollinedo
- Laboratory of Signal Transduction and Leucocyte Biology, Instituto de Biología y Genética Molecular, Facultad de Medicina, Consejo Superior de Investigaciones Científicas-Universidad de Valladolid, C/ Ramón y Cajal, E-47005 Valladolid, Spain
| | | | | | | | | | | | | |
Collapse
|
37
|
Llorens A, Vinyals A, Alia P, López-Barcons L, Gonzalez-Garrigues M, Fabra A. Metastatic ability of MXT mouse mammary subpopulations correlates with clonal expression and/or membrane-association of gelatinase A. Mol Carcinog 1997; 19:54-66. [PMID: 9180929 DOI: 10.1002/(sici)1098-2744(199705)19:1<54::aid-mc8>3.0.co;2-n] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have developed a novel murine mammary tumor system with variants representing different stages of tumor progression. The MXT-s parental cell line was established from a urethane-induced and hormone-sensitive mammary tumor. MXT-s parental cells are highly tumorigenic but poorly metastatic. MXT clones and variants were selected by either in vitro or in vivo procedures, and they differ in metastatic ability and 17 beta-estradiol dependency for tumor growth. The MXT-c1.1 and MXT-B2 cell lines produced lung metastasis after intravenous injection into 100% of syngenic mice, but only MXT-c1.1 cells were highly metastatic from intramammary tumors. The fingerprints obtained by arbitrarily primed-polymerase chain reaction demonstrated that the metastatic variants and clones had a common genetic background and resulted from clonal selection from the parental cell line. We studied whether the matrix metalloproteinase (MMP) profile is correlated with tumor progression and metastatic ability in the MXT tumor system. Gelatinases A and B were assayed in the cells, both by enzyme activity and mRNA expression. Gelatinase A was expressed in MXT-c1.1 cells, whereas MXT-B2 cells did not express either MMP. In contrast, the mammary fat pad tumors expressed both gelatinases. Membrane Type 1-MMP transcripts were also detected in MXT cells and tumors. Because the mRNA levels of gelatinase. A were low in MXT-B2 tumors, we suggested that exogenous gelatinase A bound the cell membranes of MXT-B2 cells in vivo. Indirect evidence was obtained in vitro by treatment of MXT-B2 cells with NIH/3T3 fibroblast-conditioned medium. After this treatment, we detected a gelatinolytic activity at M(r) 68,000 in the cell-membrane extract of MXT-B2 cells and an increase in migratory ability through type IV collagen matrices. On the other hand, Ha-ras gene dosage correlated positively with metastatic ability but not with either gelatinase A or gelatinase B expression. No significant differences were observed in the expression of stromelysin-1 and tissue inhibitors of MMP. Thus, in the MXT tumor system, the expression of gelatinase A or its cell association and Ha-ras gene dosage independently contribute to the metastatic phenotype.
Collapse
Affiliation(s)
- A Llorens
- Institut de Recerca Oncológica, Cancer & Metastasis Department, Hospital Duran Reynals, L'Hospitalet de Llobregat, Barcelona, Spain
| | | | | | | | | | | |
Collapse
|
38
|
Colomer A, Martínez-Mas JV, Matias-Guiu X, Llorens A, Cabezas R, Prat J, Garcia-Ameijeiras A. Sex-steroid hormone receptors in human medullary thyroid carcinoma. Mod Pathol 1996; 9:68-72. [PMID: 8821960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Three complementary techniques were used to detect sex-steroid hormone receptors in tumor tissues from seven patients with medullary thyroid carcinoma: steroid binding analysis, enzyme immune assay, and immunohistochemistry. The presence of estrogen receptors was detected by steroid binding analysis in one of seven patients, although in very low concentrations (3.17 to 5.06 fmol/mg protein). These results were confirmed by enzyme immune assay (6.35 to 9.32 fmol/mg protein). Progesterone receptors were found in five of seven patients by steroid binding analysis (11.1 to 47.9 fmol/mg protein), and progesterone receptor results were confirmed by enzyme immune assay (8.1 to 34.1 fmol/mg protein). By immunohistochemistry, progesterone receptors were focally detected in all cases, whereas all tumors were negative for estrogen receptors. In summary, our results confirm the presence of sex-steroid hormone receptors, particularly progesterone receptors in medullary thyroid carcinoma. The presence of progesterone receptors in medullary thyroid carcinoma apparently does not require the continuous presence of estrogen receptors.
Collapse
Affiliation(s)
- A Colomer
- Department of Endocrinology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
39
|
Bonfil RD, Vinyals A, Bustuoabad OD, Llorens A, Benavides FJ, Gonzalez-Garrigues M, Fabra A. Stimulation of angiogenesis as an explanation of Matrigel-enhanced tumorigenicity. Int J Cancer 1994; 58:233-9. [PMID: 7517919 DOI: 10.1002/ijc.2910580215] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Matrigel, a reconstituted extract of basement membrane, enhances the growth of different human cancer cell lines when transplanted into nude mice. Here that stimulation was confirmed in the BALB/c murine mammary-tumor cell line M3MC, as well as in human colon (SW948) and mammary (MDA-MB-468) carcinoma cell lines transplanted in nude and SCID mice, respectively. Subcutaneous and intra-mammary fat-pad inoculations of Matrigel alone generated an angiogenic response which was macroscopically evident by day 9. Histological analysis of the local host reaction occurring at the site of injection revealed an early peripheral fibroblast response, followed by mononuclear cell infiltration, solid and hollow fibroblast cords projections from the edge to the center of the Matrigel plug, and finally capillary ingrowths. Conditioned media obtained from the gels generated in vivo, acted as very strong chemoattractants for mouse lung capillary endothelial cells, stimulating their motility between 38 and 82 times with respect to the control. Our results suggest an important role of host cells recruited by Matrigel, which could favor angiogenesis of the area and thus facilitate the growth of tumor cells co-inoculated with the basement membrane extract.
Collapse
MESH Headings
- Adenocarcinoma/blood supply
- Adenocarcinoma/enzymology
- Adenocarcinoma/pathology
- Animals
- Breast Neoplasms/blood supply
- Breast Neoplasms/enzymology
- Breast Neoplasms/pathology
- Cell Division/drug effects
- Chemotaxis/drug effects
- Collagen/metabolism
- Collagen/toxicity
- Collagenases/metabolism
- Colonic Neoplasms/blood supply
- Colonic Neoplasms/enzymology
- Colonic Neoplasms/pathology
- Drug Combinations
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Female
- Humans
- Laminin/toxicity
- Mammary Neoplasms, Experimental/blood supply
- Mammary Neoplasms, Experimental/enzymology
- Mammary Neoplasms, Experimental/pathology
- Matrix Metalloproteinase 9
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Neoplasm Transplantation
- Neoplasms/blood supply
- Neoplasms/enzymology
- Neoplasms/pathology
- Neoplasms, Experimental/blood supply
- Neoplasms, Experimental/enzymology
- Neoplasms, Experimental/pathology
- Neovascularization, Pathologic
- Proteoglycans/toxicity
- Stimulation, Chemical
- Tumor Cells, Cultured
Collapse
Affiliation(s)
- R D Bonfil
- Fundación de Investigación del Cáncer, Buenos Aires, Argentina
| | | | | | | | | | | | | |
Collapse
|
40
|
Tarrés MC, Martinez SM, Montenegro S, Llorens A, Picena JC, Naves A. The eSS rat. A model of non-insulin-dependent human diabetes. Am J Pathol 1992; 141:761-3. [PMID: 1519674 PMCID: PMC1886690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- M C Tarrés
- Facultad de Ciencias Médicas y CIUNR, Universidad Nacional de Rosario, Argentina
| | | | | | | | | | | |
Collapse
|
41
|
Metzler M, Long J, Llorens A. Splenosis masquerading as small bowel neoplasm. Mo Med 1989; 86:162-4. [PMID: 2779508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Incidental discovery of a mass during laparoscopic surgery resulted in exploratory laparotomy for a young woman. The mass' uncharacteristic appearance belied its true identity as displaced splenic tissue. The authors suggest ways to identify splenosis without resorting to further surgery.
Collapse
|
42
|
Jaehne J, Meyer HJ, Wittekind C, Maschek H, Pichlmayr R, Jacobi G, Weiermann G, Vitzthum HG, Schwabe D, Manegold C, Krempien B, Kaufmann M, Bailly M, Doré JF, Fodstad Ø, Kjønniksen I, Brøgger A, Flørenes VA, Pihl A, Aamdal S, Nesland JM, Geldof AA, Rao BR, De Giovanni C, Lollini PL, Del Re B, Scotlandi K, Nicoletti G, Nanni P, Van Muijen GNP, Van Der Wiel-Miezenbeek JM, Cornelissen LMHA, Jansen CFJ, Ruiter DJ, Kieler J, Oda Y, Tokuriki Y, Tenang EM, Lamb JF, Galante E, Zanoni F, Galluzzi D, Cerrotta A, Martelli G, Guzzon A, Reduzzi D, Barberá-Guillem E, Barceló JR, Urcelay B, Alonso-Varona AI, Vidal-Vanaclocha F, Bassukas ID, Maurer-Schultze B, Storeng R, Manzotti C, Pratesi G, Schachert G, Fidler IJ, Grimstad IA, Rutt GT, Riesinger P, Frank J, Neumann G, Wissler JH, Bastert G, Liebrich W, Lehner B, Gonzer S, Schlag P, Vehmeyer K, Hajto T, Gabius HJ, Funke I, Schlimok G, Bock B, Dreps A, Schweiberer B, Riethmüller G, Nicolai U, Vykoupil KF, Wolf M, Havemann K, Georgii A, Bertrand S, N'Guyen MJ, Siracky J, Kysela B, Siracka E, Pflüger E, Schirrmacher V, Boyano MD, Hanania N, Poupon MF, Sherbet GV, Lakshmi MS, Van Roy F, Vleminckx K, Fiers W, Dragonetti C, De Bruyne G, Messiaen L, Mareel M, Kuhn S, Choritz H, Schmid U, Bihl H, Griesbach A, Matzku S, Eccles SA, Purvies HP, Miller FR, McEachern D, Ponton A, Waghorne C, Coulombe B, Kerbel RS, Breitman M, Skup D, Gingras MC, Jarolim L, Wright JA, Greenberg AH, N'Guyen MJ, Allavena G, Melchiori A, Aresu O, Percario M, Parodi S, Schmidt J, Kars P, Chader G, Albini A, Zöller M, Lissitzky JC, Bouzon M, Martin PM, Grossi IM, Taylor JD, Honn KV, Koch B, Baum W, Giedl J, Gabius HJ, Kalden JR, Hakim AA, LadÁnyi A, Timár J, Moczar E, Lapis K, Müller K, Wolf MF, Benz B, Schumacher K, Kemmner W, Morgenthaler J, Brossmer R, Hagmar B, Burns G, Erkell§ LJ, Ryd W, Paku S, Rot A, Hilario E, Unda F, Simón J, Aliño SF, Sargent NSE, Burger MM, Altevogt P, Kowitz A, Chopra H, Bandlow G, Nagel GA, Lotan R, Carralero D, Lotan D, Raz A, Skubitz APN, Koliakos GG, Furcht LT, Charonis AS, Hamann A, Jablonski-Westrich D, Jonas P, Harder R, Butcher EC, Thiele HG, Breillout F, Antoine E, Lascaux V, Boxberger HJ, Paweletz N, Bracke M, Vyncke B, Opdenakker G, Castronovo V, Foidart JM, Camacho M, Fras AF, Llorens A, Rutllant ML, Erkell LJ, Brunner G, Heredia A, Imhoff JM, Burtin P, Nakajima M, Lunec J, Parker C, Fennelly JA, Smith K, Roossien FF, La Rivière G, Roos E, Erdel M, Trefz G, Spiess E, Ebert W, Verhaegen S, Remels L, Verschueren H, Dekegel D, De Baetselier P, Van Hecke D, Hannecart-Pokorni E, Falkvoll KH, Alonso A, Baroja A, Sebbag U, Barbera-Guillem E, Behrens J, Mareel MM, Birchmeier W, Waterhouse P, Khokha R, Chambers A, Yagel S, Lala PK, Denhardt DT, Hennes R, Frantzen F, Keller R, Schwartz-Albiez R, Fondaneche MC, Mignatti P, Tsuboi R, Robbins E, Rifkin DB, Overall CM, Sacchi A, Falcioni R, Piaggio G, Rizzo MG, Perrotti N, Kennel SJ, Girschick H, Müller-Hermelink HK, Vollmers HP, Wenzel A, Liu S, Günthert U, Wesch V, Giles M, Ponta H, Herrlich P, Stade B, Hupke U, Holzmann B, Johnson JP, Sauer A, Roller E, Klumpp B, Güttler N, Lison A, Walk A, Redini F, Moczar M, Leoni F, Da Dalt MG, Ménard S, Canevari S, Miotti S, Tagliabue E, Colnaghi MI, Ostmeier H, Suter L, Possati L, Rosciani C, Recanatini E, Beatrici V, Diambrini M, Polito M, Rothbächer U, Eisenbach L, Plaksin D, Gelber C, Kushtai G, Gubbay J, Feldman M, Benke R, Benedetto A, Elia G, Sala A, Belardelli F, Lehmann JM, Ladanyi A, Hanisch FG, Sölter J, Jansen V, Böhmer G, Peter-Katalinic J, Uhlenbruck G, O'Connor R, Müller J, Kirchner T, Bover B, Tucker G, Valles AM, Gavrilovic J, Thiery JP, Kaufmann AM, Volm M, Edel G, Zühlsdorf M, Voss H, Wörmann B, Hiddemann W, De Neve W, Van Den Berge D, Van Loon R, Storme G, Zacharski LR, Wojtukiewicz MZ, Memoli V, Kisiel W, Kudryk BJ, Stump D, Piñol G, Gonzalez-Garrigues M, Fabra A, Marti F, Rueda F, Lichtner RB, Khazaie K, Timar J, Greenzhevskaya SN, Shmalko YP, Hill SE, Rees RC, MacNeil S, Millon R, Muller D, Eber M, Abecassis J, Betzler M, Bahtsky KP, Umansky VY, Krivorotov AA, Balitskaya EK, Pridatko OE, Smelkova MI, Smirnov IM, Korczak B, Fisher C, Thody AJ, Young SD, Hill RP, Frixen U, Gopas J, Segal S, Hammerling G, Bar-Eli M, Rager-Zisman B, Har-Vardi I, Alon Y, Hämmerling GJ, Perez M, Algarra I, Collado MD, Peran E, Caballero A, Garrido F, Turner GA, Blackmore M, Stern PL, Thompson S, Levin I, Kuperman O, Eyal A, Kaneti J, Notter M, Knuth A, Martin M, Chauffert B, Caignard A, Hammann A, Martin F, Dearden MT, Pelletier H, Dransfield I, Jacob G, Rogers K, Pérez-Yarza G, Cañavate ML, Lucas R, Bouwens L, Mantovani G, Serri FG, Macciò A, Zucca MV, Del Giacco GS, Pérez M, Kärre K, Apt D, Traversari C, Sensi M, Carbone G, Parmiani G, Hainaut P, Weynants P, Degiovanni G, Boon T, Marquardt P, Stulle K, Wölfel T, Herin M, Van den Eynde B, Klehmann E, Büschenfelde KHMZ, Samija M, Gerenčer M, Eljuga D, Bašić I, Heacock CS, Blake AM, D'Aleo CJ, Alvarez VL, Gresser I, Maury C, Moss J, Woodrow D, von Ardenne M, Krüger W, Möller P, Schachert HK, Itaya T, Frost P, Rodolfo M, Salvi C, Bassi C, Huland E, Huland H, Sersa G, Willingham V, Hunter N, Milas L, Schild H, von Hoegen P, Mentges B, Bätz W, Suzuki N, Mizukoshi T, Sava G, Ceschia V, Zabucchi G, Farkas-Himsley H, Schaal O, Klenner T, Keppler B, Alvarez-Diaz A, Bizzari JP, Barbera-Guillem F, Osterloh B, Bartkowski R, LÖhrke H, Schwahn E, Schafmayer A, Goerttler K, Cillo C, Ling V, Giavazzi R, Vecchi A, Luini W, Garofalo A, Iwakawa M, Arundel C, Tofilon P, Giraldi T, Perissin L, Zorzet S, Piccini P, Pacor S, Rapozzi V, Fink U, Zeuner H, Dancygier H, Classen M, Lersch C, Reuter M, Hammer C, Brendel W, Mathé G, Bourut C, Chenu E, Kidani Y, Mauvernay Y, Schally AV, Reizenstein P, Gastiaburu J, Comaru-Schally AM, Cupissol D, Jasmin C, Missot JL, Wingen F, Schmähl D, Pauwels-Vergely C, Poupon MF, Gasic TB, Ewaskiewicz JI, Gasic GJ, Pápay J, Mauvernay R, Schally A, Keiling R, Hagipantelli R, Busuttil M, VoVan ML, Misset JL, Lévi F, Musset M, Ribaud P, Hilgard P, Reissmann T, Stekar J, Voegeli R, Den Otter W, Maas HA, Dullens HFJ, Merriman RL, Tanzer LR, Shackelford KA, Bemis KG, Campbell JB, Matsumoto K. Late abstracts 186–187. Clin Exp Metastasis 1988. [DOI: 10.1007/bf01888832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
43
|
Webb S, Levy I, Wass JA, Llorens A, Penman E, Casamitjana R, Wu P, Gaya J, Martínez MJ, Rivera F. Studies on the mechanisms of somatostatin release after insulin induced hypoglycaemia in man. Clin Endocrinol (Oxf) 1984; 21:667-75. [PMID: 6150771 DOI: 10.1111/j.1365-2265.1984.tb01409.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Insulin-induced hypoglycaemia, which stimulates gastric acid secretion, is associated with an increase in circulating somatostatin levels in man. In order to assess the mechanisms involved in this rise, six normal volunteers connected to a Biostator for continuous glucose monitoring were studied, on three separate occasions. On each occasion after basal blood sampling, 0.15 i.u./kg body weight of insulin was administered i.v. and further samples were obtained intermittently over 150 min. On one occasion, dextrose was infused by the Biostator to prevent hypoglycaemia, while on the other two, a constant infusion of either normal saline or the specific H2 antagonist cimetidine was administered. Insulin plus dextrose caused no significant changes in circulating somatostatin levels, whereas insulin plus saline was associated with a marked, sustained and significant rise in all subjects; insulin plus cimetidine also produced a rise but it was delayed; the area under the curve was significantly (P less than 0.05) greater with insulin plus saline than with insulin plus cimetidine. These results show that in man insulin itself does not stimulate somatostatin secretion directly, but indirectly via hypoglycaemia. Further, the inhibition of gastric acid secretion with cimetidine reduces somatostatin release during insulin-induced hypoglycaemia. This suggests that gastric acid may mediate somatostatin secretion associated with insulin-induced hypoglycaemia.
Collapse
|
44
|
Carter P, Sagroun B, Llorens A, Saffar JL. [Symmetry of the bone lesions of periodontitis in the golden hamster]. J Biol Buccale 1982; 10:287-92. [PMID: 6963271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In 8 month old hamsters, a spontaneous bone resorption occurs on both lingual and palatal aspects of the alveolar process, whereas, the buccal aspects are much less severely affected. A periodontitis lasting more than 6 months markedly increased this process in animals of the same age. In both maxillae, similar levels of bone resorption occurred on both left and right quadrants. A parallel degree of involvement was noted in the upper and lower jaws. However, the progress of the lesions seemed less rapid in the maxilla compared to the mandible. For experimental periods less than 6 months, less sever periodontitis could be recorded if macroscopical studies were conducted in the maxillae rather than the mandibles.
Collapse
|
45
|
Camps J, Jiménez W, Llorens A, Rivera-Fillat F. [Synthesis of cyclic AMP from renal cortex in vitro (author's transl)]. Rev Esp Fisiol 1981; 37:31-6. [PMID: 6264552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The parathyroid-hormone sensitive adenylate-cyclase from renal rat cortex has been studied. Mg2+ acts as stimulator at a specific locus increasing the apparent Vmax slightly from 50 to 60 nmol of cAMP per gram of protein if the Mg2+ concentration increases from 3.25 to 16 mM, and decreases the apparent KM from 2 to 0.4 mM. Fluoride decreases the apparent KM from 5 mM in NaF concentrations of 0 to 2 mM in NaF concentrations 2 mM. Magnesium ion also decreases the apparent Ka for NaF.
Collapse
|