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Anliker-Ort M, Dingemanse J, Farine H, Groenen P, Kornberger R, van den Anker J, Kaufmann P. Multiple-ascending doses of ACT-1014-6470, an oral complement factor 5a receptor 1 (C5a 1 receptor) antagonist: Tolerability, pharmacokinetics and target engagement. Br J Clin Pharmacol 2023; 89:380-389. [PMID: 36000981 DOI: 10.1111/bcp.15508] [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: 05/25/2022] [Revised: 08/08/2022] [Accepted: 08/15/2022] [Indexed: 11/28/2022] Open
Abstract
AIMS Targeting the complement factor 5a receptor 1 (C5a1 receptor) offers potential to treat various autoimmune diseases. The C5a1 receptor antagonist ACT-1014-6470 was well tolerated in a single-ascending dose study in healthy subjects. This double-blind, randomized, placebo-controlled study aimed to investigate the safety, tolerability, pharmacokinetics (PK) and target engagement of multiple-ascending doses of ACT-1014-6470. METHODS Per dose level, 10 healthy male and female subjects of nonchildbearing potential (1:1 sex ratio) were enrolled to assess 30, 60 and 120 mg ACT-1014-6470 administered twice daily for 4.5 days under fed conditions. Adverse events, clinical laboratory data, vital signs, electrocardiogram and PK blood samples were collected up to 120 h post last dose and ex vivo stimulated matrix metalloproteinase 9 was quantified as target engagement biomarker. At the 60-mg dose level, PK samples were collected until 8 weeks post last dose. RESULTS The total adverse event number was 57 and no treatment-related safety pattern was apparent. At steady state, ACT-1014-6470 reached maximum plasma concentrations after 2-3 h and the half-life estimated up to Day 10 was 115-146 h across dose levels. Exposure parameters increased dose-proportionally, steady state was attained between Day 3-5, and ACT-1014-6470 accumulated 2-fold. At the 60-mg dose level, ACT-1014-6470 was quantifiable until 8 weeks after the last dose. Matrix metalloproteinase 9 release was suppressed to endogenous background concentrations up to the last sampling time point, confirming sustained target engagement of ACT-1014-6470. CONCLUSION The compound was generally safe and well tolerated at all dose levels, warranting further clinical investigations.
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Affiliation(s)
- Marion Anliker-Ort
- Department of Clinical Pharmacology, Idorsia Pharmaceuticals Ltd, Allschwil, Switzerland
- Paediatric Pharmacology and Pharmacometrics, University Children's Hospital Basel (UKBB), University of Basel, Basel, Switzerland
| | - Jasper Dingemanse
- Department of Clinical Pharmacology, Idorsia Pharmaceuticals Ltd, Allschwil, Switzerland
| | - Hervé Farine
- Translational Biomarkers, Idorsia Pharmaceuticals Ltd, Allschwil, Switzerland
| | - Peter Groenen
- Translational Biomarkers, Idorsia Pharmaceuticals Ltd, Allschwil, Switzerland
| | | | - John van den Anker
- Paediatric Pharmacology and Pharmacometrics, University Children's Hospital Basel (UKBB), University of Basel, Basel, Switzerland
| | - Priska Kaufmann
- Department of Clinical Pharmacology, Idorsia Pharmaceuticals Ltd, Allschwil, Switzerland
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Cowan KJ, Golob M, Goodman J, Laurén A, Andersen L, Decker PD, Dejager L, Fjording MS, Groenen P, Jasnowski R, Justies N, Kimberg M, Kunz U, Lawrence J, Richter M, Sordé L, Trigt RV, Vermet L, Vitaliti A, Wright M, Timmerman P. Biomarker context-of-use: how organizational design can impact the implementation of the appropriate biomarker assay strategy. Bioanalysis 2022; 14:911-917. [PMID: 35904153 DOI: 10.4155/bio-2022-0143] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Since 2011, the European Bioanalysis Forum has been discussing the topic of context-of-use for biomarker assays, in support of a cross-industry implementation of its principles. The discussions have led to the acknowledgement of the challenges that we face as an industry in implementing these principles. In addition to scientific recommendations, the European Bioanalysis Forum has addressed these challenges by providing recommendations on organizational design, and what works in both sponsor and contract research organizations, to support and enable context-of-use across biomarker strategies. Here, we highlight the key considerations for organizational design to help ensure that biomarker assays are characterized and validated according to the right context-of-use, to ensure that the right decisions based on the biomarker data can be made during drug development.
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Affiliation(s)
- Kyra J Cowan
- Merck KGaA, New Biological Entities Drug Metabolism & Pharmacokinetics, Darmstadt, 64293, Germany
| | | | - Joanne Goodman
- Integrated Bioanalysis, Clinical Pharmacology & Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, CB21 6GH, UK
| | - Anna Laurén
- Novo Nordisk A/S, Non-clinical & Clinical Assay Sciences, Global Discovery & Development Sciences, Global Drug Discovery, Maløv, DK-2760, Denmark
| | - Lene Andersen
- Lundbeck A/S, Experimental Medicine & Clinical Development, Valby, DK-2500, Denmark representing Orphazyme A/S, Clinical Development, Copenhagen N, DK-2200, Denmark
| | | | - Lien Dejager
- UCB Pharma, Development Science, Translational Biomarkers & Bioanalysis, Chemin du Foriest, Braine-l'Alleud, B-1420, Belgium
| | | | - Peter Groenen
- Idorsia Pharmaceuticals Ltd., Translational Biomarkers, Allschwil, 4123, Switzerland
| | | | - Nicole Justies
- Roche Innovation Center Basel, Roche Pharmaceutical Research & Early Development, Basel, 4070, Switzerland
| | - Matti Kimberg
- Synexa Life Sciences BV, Leiden, 2333 CS, The Netherlands
| | - Ulrich Kunz
- Boehringer Ingelheim Pharma GmbH & Co. KG, Translational Medicine & Clinical Pharmacology, Biberach an der Riss, 88397, Germany
| | | | - Mario Richter
- AbbVie Deutschland GmbH & Co KG, DMPK-BA, Knollstrasse, Ludwigshafen, 67061, Germany
| | - Laetitia Sordé
- Sobi AG, Bioanalytical Sciences, Plan-les-Ouates, 1228, Switzerland
| | | | - Laurent Vermet
- Sanofi Research & Development, Translational Medicine & Early Development, Biomarkers & Clinical Bioanalysis, Montpellier, 34080, France
| | - Alessandra Vitaliti
- Novartis Institutes for Biomedical Research, Novartis Pharma AG, Basel, 4056, Switzerland
| | - Michael Wright
- GlaxoSmithKline, Bioanalysis Immunogenicity & Biomarkers, Stevenage, SG1 2NY, UK
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Hartl D, Keller M, Klenk A, Murphy M, Martinic M, Pierlot G, Groenen P, Strasser D. THU0008 DEVELOPMENT OF A NOVEL TRANSLATIONAL IN SILICO INDICATION DISCOVERY FRAMEWORK: EXEMPLIFIED BY THE CLINICAL COMPOUND CENERIMOD. Ann Rheum Dis 2020. [DOI: 10.1136/annrheumdis-2020-eular.3520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Background:To explore the full therapeutic spectrum of a drug it is crucial to consider its potential effectiveness in all diseases. Serendipitous clinical observations have often shown that approved drugs and those in development to be efficacious in indications different to those originally tested for. Traditional approaches to match a drug candidate with possible indications are mostly based on matching drug mechanistic knowledge with disease pathophysiology. Proof-of-concept trials or elaborate pre-clinical studies in animal models do not allow for a broad assessment due to high costs and slow progress. Gene expression changes in patients or animal models represent a good proxy to comprehensively assess both disease and drug effects. Furthermore, this data type can be integrated with a plethora of publicly available data.Objectives:Generation of a novel in silico framework to support the selection and expansion of potential indications which associate with a compound or approved drug. The framework was exemplified by the clinical compound cenerimod, a potent, selective, and orally active sphingosine-1-phosphate receptor 1 modulator (Piali et al., 2017).Methods:A total of ~13’000 public patient gene expression datasets from ~140 diseases were evaluated against cenerimod gene expression data generated in mouse disease models. To improve comparability of studies across platforms and species, computer algorithms (neural networks) were trained and employed to reduce noise within the data sets and improve signal. The predicted response to cenerimod for individual patients was contrasted against clinical patient characteristics.Results:The neural network algorithm efficiently reduced experimental noise and improved sensitivity in the gene expression data. The results predicted cenerimod to be efficacious in several auto-immune diseases foremost SLE. Additionally, focused analysis on individual patients rather than disease cohorts revealed potential determinants predictive of maximal clinical response, with the highest predicted clinical response for cenerimod in patients with severe inflammatory endotype and/or high SLE Disease Activity Index (SLEDAI).Conclusion:Combining preclinical compound data with the wealth of public disease gene expression data, provides great potential to support indication selection. The novel in silico framework identified SLE as a prime potential indication for cenerimod and supported the cenerimod phase 2b clinical trial in patients with SLE (CARE study,NCT03742037).References:[1]Piali, L., Birker-Robaczewska, M., Lescop, C., Froidevaux, S., Schmitz, N., Morrison, K., … Nayler, O. (2017). Cenerimod, a novel selective S1P1 receptor modulator with unique signaling properties. Pharmacology Research & Perspectives, 5(6), 1–12.https://doi.org/10.1002/prp2.370Disclosure of Interests:Dominik Hartl Shareholder of: Idorsia shares, Employee of: Idorsia employee, Marcel Keller Shareholder of: Idorsia options/shares, Employee of: Idorsia employee, Axel Klenk Shareholder of: Idorsia option/shares, Employee of: Idorsia employee, Mark Murphy Shareholder of: Idorsia shares and stock options, Employee of: Idorsia employee, Marianne Martinic Shareholder of: Idorsia options/shares, Employee of: Idorsia employee, Gabin Pierlot Shareholder of: Idorsia options/shares, Employee of: Idorsia employee, Peter Groenen Shareholder of: Idorsia options/shares, Employee of: Idorsia employee, Daniel Strasser Shareholder of: Idorsia options/shares, Employee of: Idorsia employee
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Mc Connell L, Houghton O, Catherwood M, Gazdova J, Stewart P, Oniscu A, Groenen P, Kroeze L, Taniere P, Flanagan A, Stobl A, Salto-Tellez M, De Castro DG. Clinical validation of a novel assay for the detection of diagnostic alterations in sarcomas. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz283.050] [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: 11/14/2022] Open
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Tremaine L, Brian W, DelMonte T, Francke S, Groenen P, Johnson K, Li L, Pearson K, Marshall JC. The role of ADME pharmacogenomics in early clinical trials: perspective of the Industry Pharmacogenomics Working Group (I-PWG). Pharmacogenomics 2015; 16:2055-67. [PMID: 26616152 DOI: 10.2217/pgs.15.141] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [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: 12/14/2022] Open
Abstract
Genetic polymorphisms in metabolizing enzymes and drug transporters have been shown to significantly impact the exposure of drugs having a high dependence on a single mechanism for their absorption, distribution or clearance, such that genotyping can lead to actionable steps in disease treatment. Recently, global regulatory agencies have provided guidance for assessment of pharmacogenomics during early stages of drug development, both in the form of formal guidance and perspectives published in scientific journals. The Industry Pharmacogenomics Working Group (I-PWG), conducted a survey among member companies to assess the practices relating to absorption, distribution, metabolism, excretion pharmacogenomics) during early stages of clinical development, to assess the impact of the recent Regulatory Guidance issued by the US FDA and EMA on Industry practices.
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Affiliation(s)
- Larry Tremaine
- Pfizer Inc., Worldwide Research & Development, Department of Pharmacokinetics, Dynamics & Metabolism, Eastern Point Road, Groton, CT 06340, USA
| | - William Brian
- Sanofi, Disposition, Safety & Animal Research, 55 Corporate Drive, Bridgewater, NJ 08807, USA
| | - Terrye DelMonte
- Bristol Myers Squibb, Clinical Sample Strategy & Operations, Exploratory & Clinical Translational Research, 311 Pennington Rocky Hill Rd, Pennington, NJ 08534, USA
| | - Stephan Francke
- Janssen Research & Development, 1400 McKean Rd, PO Box 776, Spring House, PA 19477, USA
| | - Peter Groenen
- Actelion Pharmaceuticals Ltd, Translational Science, Gewerbestrasse 16, 4102 Allschwil, Switzerland
| | - Keith Johnson
- Veritas Genetics Inc., 99 Conifer Hill Drive, Danvers, MA 01923, USA.,Novartis Institutes for Bio Medical Research, Inc., 250 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Lei Li
- Veritas Genetics Inc., 99 Conifer Hill Drive, Danvers, MA 01923, USA.,Novartis Institutes for Bio Medical Research, Inc., 250 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Kimberly Pearson
- Sanofi, Disposition, Safety & Animal Research, 55 Corporate Drive, Bridgewater, NJ 08807, USA
| | - Jean-Claude Marshall
- Pfizer Inc., Worldwide Research & Development, Department of Pharmacokinetics, Dynamics & Metabolism, Eastern Point Road, Groton, CT 06340, USA
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Welford RWD, Garzotti M, Marques Lourenço C, Mengel E, Marquardt T, Reunert J, Amraoui Y, Kolb SA, Morand O, Groenen P. Plasma lysosphingomyelin demonstrates great potential as a diagnostic biomarker for Niemann-Pick disease type C in a retrospective study. PLoS One 2014; 9:e114669. [PMID: 25479233 PMCID: PMC4257710 DOI: 10.1371/journal.pone.0114669] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 11/12/2014] [Indexed: 11/29/2022] Open
Abstract
Niemann-Pick disease type C (NP-C) is a devastating, neurovisceral lysosomal storage disorder which is characterised by variable manifestation of visceral signs, progressive neuropsychiatric deterioration and premature death, caused by mutations in the NPC1 and NPC2 genes. Due to the complexity of diagnosis and the availability of an approved therapy in the EU, improved detection of NP-C may have a huge impact on future disease management. At the cellular level dysfunction or deficiency of either the NPC1 or NPC2 protein leads to a complex intracellular endosomal/lysosomal trafficking defect, and organ specific patterns of sphingolipid accumulation. Lysosphingolipids have been shown to be excellent biomarkers of sphingolipidosis in several enzyme deficient lysosomal storage disorders. Additionally, in a recent study the lysosphingolipids, lysosphingomyelin (SPC) and glucosylsphingosine (GlcSph), appeared to be elevated in the plasma of three adult NP-C patients. In order to investigate the clinical utility of SPC and GlcSph as diagnostic markers, an in-depth fit for purpose biomarker assay validation for measurement of these biomarkers in plasma by liquid chromatography-tandem mass spectrometry was performed. Plasma SPC and GlcSph are stable and can be measured accurately, precisely and reproducibly. In a retrospective analysis of 57 NP-C patients and 70 control subjects, median plasma SPC and GlcSph were significantly elevated in NP-C by 2.8-fold and 1.4-fold respectively. For miglustat-naïve NP-C patients, aged 2–50 years, the area under the ROC curve was 0.999 for SPC and 0.776 for GlcSph. Plasma GlcSph did not correlate with SPC levels in NP-C patients. The data indicate excellent potential for the use of lysosphingomyelin in NP-C diagnosis, where it could be used to identify NP-C patients for confirmatory genetic testing.
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Affiliation(s)
| | | | | | - Eugen Mengel
- Department of Lysosomal Storage Disorder, Villa Metabolica, Center for Paediatric and Adolescent Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | | | | | - Yasmina Amraoui
- Department of Lysosomal Storage Disorder, Villa Metabolica, Center for Paediatric and Adolescent Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | | | | | - Peter Groenen
- Actelion Pharmaceuticals Ltd, Allschwil, Switzerland
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Franc MA, Cohen N, Warner AW, Shaw PM, Groenen P, Snapir A. Coding of DNA Samples and Data in the Pharmaceutical Industry: Current Practices and Future Directions—Perspective of the I-PWG. Clin Pharmacol Ther 2011; 89:537-45. [DOI: 10.1038/clpt.2010.306] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Ye Y, Kawamura K, Sasaki M, Kawamura N, Groenen P, Sollewijn Gelpke MD, Kumagai J, Fukuda J, Tanaka T. Leptin and ObRa/MEK signalling in mouse oocyte maturation and preimplantation embryo development. Reprod Biomed Online 2009; 19:181-90. [PMID: 19712552 DOI: 10.1016/s1472-6483(10)60070-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Recent studies indicate that LH stimulates production of ovarian paracrine factors that induce meiosis of the oocyte. DNA microarray analyses of ovarian transcripts were performed in mice and major increases of a short isoform of leptin receptor, ObRa, were identified by the preovulatory LH/human chorionic gonadotrophin (HCG) surge. In oocytes, the level of ObRa transcripts was increased shortly after HCG stimulation, whereas the level of ObRb transcripts was not changed. Leptin was produced by cumulus, granulosa, theca and interstitial cells of ovaries and its transcript level was not regulated during gonadotrophin treatment. Treatment with leptin promoted germinal vesicle breakdown (GVBD) in oocytes within preovulatory follicles, and enhance first polar body extrusion in both cumulus-oocyte complexes and denuded oocytes. The leptin-promoted GVBD and first polar body extrusion were blocked by a mitogen-activated protein kinase extracellular signal regulated kinase kinases (MEK)1/2 inhibitor, U0126, but not its inactive analogue U0124. Furthermore, leptin promoted fertilization of oocytes and the in-vitro development of zygotes to preimplantation embryos. These findings suggest paracrine roles of leptin in the enhancement of nuclear maturation of oocytes through MEK1/2 signalling, and in the promotion of cytoplasmic maturation essential for successful oocyte development to the preimplantation embryos.
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Affiliation(s)
- Yinghui Ye
- Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita, Japan.
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Ye Y, Kawamura K, Sasaki M, Kawamura N, Groenen P, Gelpke MDS, Rauch R, Hsueh AJW, Tanaka T. Kit ligand promotes first polar body extrusion of mouse preovulatory oocytes. Reprod Biol Endocrinol 2009; 7:26. [PMID: 19341483 PMCID: PMC2676294 DOI: 10.1186/1477-7827-7-26] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Accepted: 04/03/2009] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Shortly after stimulation by the preovulatory surge of luteinizing hormone (LH), oocytes arrested at the late prophase I resume meiosis characterized by germinal vesicle breakdown (GVBD), chromosome condensation, and extrusion of the first polar body in preparation for fertilization and early embryonic development. However, oocytes express few or no LH receptors and are insensitive to direct LH stimulation. Thus, factors released by granulosa or theca cells expect to convey the LH stimuli to oocytes. To identify candidate ligand-receptor pairs potentially involved in the process of oocyte maturation, we performed DNA microarray analyses of ovarian transcripts in mice and identified Kit ligand (Kitl) as an ovarian factor stimulated by the LH/hCG surge. The purpose of this study is to investigate the roles of KITL in the nuclear and cytoplasmic maturation of preovulatory mouse oocytes. METHODS The levels of Kitl and c-kit transcripts in mouse ovaries and isolated ovarian cells were determined by real-time RT-PCR, while expression of KITL protein was examined by immunohistochemistry. Follicle culture, cumulus-oocyte complexes (COC) and denuded oocytes culture were used to evaluate the effect of KITL on mouse oocyte nuclear maturation. To assess the effect of KITL treatment on the cytoplasmic maturation of preovulatory oocytes, we performed in vitro maturation of oocytes followed by in vitro fertilization. RESULTS Major increase of Kitl transcripts in granulosa cells and mouse ovaries, and predominant expression of c-kit in preovulatory oocytes were identified by real-time RT-PCR. Predominant expression of KITL protein was found in granulosa cells of preovulatory and small antral follicles at 4 h after hCG treatment. In vitro cultures demonstrated that treatment with KITL enhanced first polar body extrusion in a dose-dependent manner. Moreover, treatment of COC with KITL enhanced first polar body extrusion with increase in cyclin B1 synthesis which is important for the progression of meiotic maturation after GVBD. In contrast, treatment of cultured preovulatory follicles with KITL did not affect GVBD and KITL has no effect on cytoplasmic maturation of preovulatory oocytes. CONCLUSION Our findings suggest potential paracrine roles of KITL in the nuclear maturation of preovulatory oocytes by promoting first polar body extrusion.
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Affiliation(s)
- Yinghui Ye
- Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita, Japan
- Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Zhejiang, PR China
| | - Kazuhiro Kawamura
- Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita, Japan
| | - Mitsue Sasaki
- Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita, Japan
| | - Nanami Kawamura
- Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita, Japan
- Department of Dermatology and Plastic Surgery, Akita University School of Medicine, Akita, Japan
| | | | | | - Rami Rauch
- Division of Reproductive Biology, Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, California, USA
| | - Aaron JW Hsueh
- Division of Reproductive Biology, Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, California, USA
| | - Toshinobu Tanaka
- Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita, Japan
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Kawamura K, Ye Y, Kawamura N, Jing L, Groenen P, Gelpke MS, Rauch R, Hsueh AJW, Tanaka T. Completion of Meiosis I of preovulatory oocytes and facilitation of preimplantation embryo development by glial cell line-derived neurotrophic factor. Dev Biol 2007; 315:189-202. [PMID: 18234170 DOI: 10.1016/j.ydbio.2007.12.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Revised: 12/05/2007] [Accepted: 12/19/2007] [Indexed: 01/15/2023]
Abstract
Optimal maturation of oocytes and successful development of preimplantation embryos is essential for reproduction. We performed DNA microarray analyses of ovarian transcripts and identified glial cell line-derived neurotrophic factor (GDNF) secreted by cumulus, granulosa, and theca cells as an ovarian factor stimulated by the preovulatory LH/hCG surge. Treatment of cumulus-oocyte complexes with GDNF enhanced first polar body extrusion with increase in cyclin B1 synthesis and the GDNF actions are likely mediated by its receptor GDNF family receptor-alpha1 (GFRA1) and a co-receptor ret proto-oncogene (Ret), both expressed in oocytes. However, treatment with GDNF did not affect germinal vesicle breakdown and cytoplasmic maturation of oocytes. During the preimplantation stages, GDNF was expressed in pregnant oviducts and uteri, whereas GFRA1 and Ret were expressed in embryos throughout early development with an increase after the early blastocyst stage. In blastocysts, both GDNF and GFRA1 were exclusively localized in trophectoderm cells, whereas Ret was detected in both cell lineages. Treatment with GDNF promoted the development of two-cell-stage embryos into blastocysts showing increased cell proliferation and decreased apoptosis mainly in trophectoderm cells. Our findings suggest potential paracrine roles of GDNF in the promotion of completion of meiosis I and the development of early embryos.
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Affiliation(s)
- Kazuhiro Kawamura
- Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita 010-8543, Japan.
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Thomas P, Pang Y, Dong J, Groenen P, Kelder J, de Vlieg J, Zhu Y, Tubbs C. Steroid and G protein binding characteristics of the seatrout and human progestin membrane receptor alpha subtypes and their evolutionary origins. Endocrinology 2007; 148:705-18. [PMID: 17082257 DOI: 10.1210/en.2006-0974] [Citation(s) in RCA: 224] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A novel progestin receptor (mPR) with seven-transmembrane domains was recently discovered in spotted seatrout and homologous genes were identified in other vertebrates. We show that cDNAs for the mPR alpha subtypes from spotted seatrout (st-mPRalpha) and humans (hu-mPRalpha) encode progestin receptors that display many functional characteristics of G protein-coupled receptors. Flow cytometry and immunocytochemical staining of whole MDA-MB-231 cells stably transfected with the mPRalphas using antibodies directed against their N-terminal regions show the receptors are localized on the plasma membrane and suggest the N-terminal domain is extracellular. Both recombinant st-mPRalpha and hu-mPRalpha display high affinity (Kd 4.2-7.8 nm), limited capacity (Bmax 0.03-0.32 nm), and displaceable membrane binding specific for progestins. Progestins activate a pertussis toxin-sensitive inhibitory G protein (G(i)) to down-regulate membrane-bound adenylyl cyclase activity in both st-mPRalpha- and hu-mPRalpha-transfected cells. Coimmunoprecipitation experiments demonstrate the receptors are directly coupled to the G(i) protein. Similar to G protein-coupled receptors, dissociation of the receptor/G protein complex results in a decrease in ligand binding to the mPRalphas and mutation of the C-terminal, and third intracellular loop of st-mPRalpha causes loss of ligand-dependent G protein activation. Phylogenetic analysis indicates the mPRs are members of a progesterone and adipoQ receptor (PAQR) subfamily that is only present in chordates, whereas other PAQRs also occur in invertebrates and plants. Progesterone and adipoQ receptors are related to the hemolysin3 family and have origins in the Eubacteria. Thus, mPRs arose from Eubacteria independently from members of the GPCR superfamily, which arose from Archeabacteria, suggesting convergent evolution of seven-transmembrane hormone receptors coupled to G proteins.
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Affiliation(s)
- Peter Thomas
- University of Texas Marine Science Institute, 750 Channel View Drive, Port Aransas, Texas 78373, USA.
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Klootwijk R, Hol FA, Wu M, Willemen JJHT, Groenen P, Hamel B, Straatman H, Steegers-Theunissen RPM, Mariman ECM, Franke B. Genetic variation analysis of MLP, TFAP2A, and CSK in patients with neural tube defects. J Med Genet 2003; 40:e43. [PMID: 12676916 PMCID: PMC1735439 DOI: 10.1136/jmg.40.4.e43] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Peeters H, Debeer P, Groenen P, Van Esch H, Vanderlinden G, Eyskens B, Mertens L, Gewillig M, Van de Ven W, Fryns JP, Devriendt K. Recurrent involvement of chromosomal region 6q21 in heterotaxy. Am J Med Genet 2001; 103:44-7. [PMID: 11562933 DOI: 10.1002/ajmg.1499] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We present a patient with heterotaxy and a de novo, apparently balanced reciprocal translocation with breakpoints at 6q21 and 20p13. Another patient with heterotaxy was previously reported with a de novo balanced translocation involving chromosome band 6q21. The breakpoints in both patients on 6q21 were found to be located in the same chromosomal region spanning maximally 2 Mb. We speculate that the two breakpoints lead to the disruption of the function of a single gene, either directly or through long distance effects. Alternatively, the present observation suggests additional heterogeneity in heterotaxy in humans.
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Affiliation(s)
- H Peeters
- Centre for Human Genetics, University of Leuven, Belgium
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Vermeire S, Joossens S, Peeters M, Monsuur F, Marien G, Bossuyt X, Groenen P, Vlietinck R, Rutgeerts P. Comparative study of ASCA (Anti-Saccharomyces cerevisiae antibody) assays in inflammatory bowel disease. Gastroenterology 2001; 120:827-33. [PMID: 11231936 DOI: 10.1053/gast.2001.22546] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [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] [Indexed: 12/16/2022]
Abstract
BACKGROUND & AIMS Anti-Saccharomyces cerevisiae antibody (ASCA) is a serologic marker associated with Crohn's disease (CD). Although there is still discussion on its clinical value, several companies each promote their own ASCA assay to be used in the gastroenterologist's practice at considerable expense. The aim of this study was to determine whether different ASCA assays agree sufficiently well for the results to be used interchangeably. METHODS Blood obtained from a large cohort of IBD patients with inflammatory bowel disease (IBD; 100 with CD, 100 with ulcerative colitis [UC]) and 178 controls (100 healthy blood donors and 78 patients with non-IBD diarrheal illnesses) was studied with 4 different ASCA assays. Sensitivity, specificity, and positive predictive value were compared. Agreement between assays was evaluated. RESULTS Sensitivity of ASCA for CD ranged between 41% and 76%. Sensitivity was inversely related to specificity and positive predictive value. Results correlated well overall (range = 0.54-0.90) and the different ROC curves showed good agreement. When recalculated cutoff points were used, interchangeability increased. However, large differences were seen when absolute values were compared. CONCLUSIONS A large range in sensitivities and specificities of ASCA for CD is seen with different ASCA assays, mainly as a consequence of the cutoff value chosen for each individual assay. Although agreement between and within assays is good, caution is important when absolute values are used. Standardization of ASCA measurements is greatly needed.
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Affiliation(s)
- S Vermeire
- Gastroenterology Unit, UZ Gasthuisberg, Leuven, Belgium
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16
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17
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Boudrez A, Beullens M, Groenen P, Van Eynde A, Vulsteke V, Jagiello I, Murray M, Krainer AR, Stalmans W, Bollen M. NIPP1-mediated interaction of protein phosphatase-1 with CDC5L, a regulator of pre-mRNA splicing and mitotic entry. J Biol Chem 2000; 275:25411-7. [PMID: 10827081 DOI: 10.1074/jbc.m001676200] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [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] [Indexed: 11/06/2022] Open
Abstract
NIPP1 is a regulatory subunit of a species of protein phosphatase-1 (PP1) that co-localizes with splicing factors in nuclear speckles. We report that the N-terminal third of NIPP1 largely consists of a Forkhead-associated (FHA) protein interaction domain, a known phosphopeptide interaction module. A yeast two-hybrid screening revealed an interaction between this domain and a human homolog (CDC5L) of the fission yeast protein cdc5, which is required for G(2)/M progression and pre-mRNA splicing. CDC5L and NIPP1 co-localized in nuclear speckles in COS-1 cells. Furthermore, an interaction between CDC5L, NIPP1, and PP1 in rat liver nuclear extracts could be demonstrated by co-immunoprecipitation and/or co-purification experiments. The binding of the FHA domain of NIPP1 to CDC5L was dependent on the phosphorylation of CDC5L, e.g. by cyclin E-Cdk2. When expressed in COS-1 or HeLa cells, the FHA domain of NIPP1 did not affect the number of cells in the G(2)/M transition. However, the FHA domain blocked beta-globin pre-mRNA splicing in nuclear extracts. A mutation in the FHA domain that abolished its interaction with CDC5L also canceled its anti-splicing effects. We suggest that NIPP1 either targets CDC5L or an associated protein for dephosphorylation by PP1 or serves as an anchor for both PP1 and CDC5L.
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Affiliation(s)
- A Boudrez
- Afdeling Biochemie and Center for Human Genetics (VIB), Faculteit Geneeskunde, Katholieke Universiteit Leuven, Belgium
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18
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Van Esch H, Groenen P, Nesbit MA, Schuffenhauer S, Lichtner P, Vanderlinden G, Harding B, Beetz R, Bilous RW, Holdaway I, Shaw NJ, Fryns JP, Van de Ven W, Thakker RV, Devriendt K. GATA3 haplo-insufficiency causes human HDR syndrome. Nature 2000; 406:419-22. [PMID: 10935639 DOI: 10.1038/35019088] [Citation(s) in RCA: 358] [Impact Index Per Article: 14.9] [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: 11/08/2022]
Abstract
Terminal deletions of chromosome 10p result in a DiGeorge-like phenotype that includes hypoparathyroidism, heart defects, immune deficiency, deafness and renal malformations. Studies in patients with 10p deletions have defined two non-overlapping regions that contribute to this complex phenotype. These are the DiGeorge critical region II (refs 1, 2), which is located on 10p13-14, and the region for the hypoparathyroidism, sensorineural deafness, renal anomaly (HDR) syndrome (Mendelian Inheritance in Man number 146255), which is located more telomeric (10p14-10pter). We have performed deletion-mapping studies in two HDR patients, and here we define a critical 200-kilobase region which contains the GATA3 gene. This gene belongs to a family of zinc-finger transcription factors that are involved in vertebrate embryonic development. Investigation for GATA3 mutations in three other HDR probands identified one nonsense mutation and two intragenic deletions that predicted a loss of function, as confirmed by absence of DNA binding by the mutant GATA3 protein. These results show that GATA3 is essential in the embryonic development of the parathyroids, auditory system and kidneys, and indicate that other GATA family members may be involved in the aetiology of human malformations.
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Affiliation(s)
- H Van Esch
- Laboratory for Molecular Oncology, Centre for Human Genetics, University of Leuven and Flanders Interuniversity Institute for Biotechnology, Belgium
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Van Esch H, Groenen P, Fryns JP, Van de Ven W, Devriendt K. The phenotypic spectrum of the 10p deletion syndrome versus the classical DiGeorge syndrome. Genet Couns 1999; 10:59-65. [PMID: 10191430] [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: 02/11/2023]
Abstract
We reviewed 36 patients with a deletion of the short arm of chromosome 10 and a partial DiGeorge syndrome. We compared the phenotypes observed in these del(10p) patients with the classical DiGeorge phenotype associated with del(22q11), pointing out both similarities and differences. Some features, such as sensorineural hearing loss, seem to be highly associated with a deletion of 10p but are absent in the classical DiGeorge spectrum caused by del(22q11).
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Van Esch H, Groenen P, Daw S, Poffyn A, Holvoet M, Scambler P, Fryns JP, Van de Ven W, Devriendt K. Partial DiGeorge syndrome in two patients with a 10p rearrangement. Clin Genet 1999; 55:269-76. [PMID: 10361989 DOI: 10.1034/j.1399-0004.1999.550410.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [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: 11/23/2022]
Abstract
We describe 2 patients with a partial DiGeorge syndrome (facial dysmorphism, hypoparathyroidism, renal agenesis, mental retardation) and a rearrangement of chromosome 10p. The first patient carries a complex chromosomal rearrangement, with a reciprocal insertional translocation between the short arm of chromosome 10 and the long arm of chromosome 8, with karyotype 46, XY ins(8;10) (8pter 8q13::10p15-->10p14::8q24.1-->8qter) ins(10:8) (10pter--> 10p15::8q24.1-->8q13::10p14-->10qter). The karyotype of the second patient shows a terminal deletion of the short arm of chromosome 10. In both patients, the breakpoints on chromosome 10p reside outside the previously determined DiGeorge critical region II (DGCRII). This is in agreement with previous reports of patients with a terminal deletion of 10p with breakpoints distal to the DGCRII and renal malformations/hypoparathyroidism, and thus adds to evidence that these features may be caused by haploinsufficiency of one or more genes distal to the DGCRII.
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Affiliation(s)
- H Van Esch
- Laboratory for Molecular Oncology, Center for Human Genetics, University of Leuven and Flanders Interuniversity Institute for Biotechnology, Belgium
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Abstract
Myotonic dystrophy (DM) is a highly variable multisystemic disease belonging to the rather special class of trinucleotide expansion disorders. DM results from dynamic expansion of a perfect (CTG)n repeat situated in a gene-dense region on chromosome 19q. Based on findings in patient materials or cellular and animal models, many mechanisms for the causes and consequences of repeat expansion have been proposed; however, none of them has enjoyed prolonged support. There is now circumstantial evidence that long (CTG)n repeats may affect the expression of any of at least three genes, myotonic dystrophy protein kinase (DMPK), DMR-N9 (gene 59), and a DM-associated homeodomain protein (DMAHP). Furthermore, the new findings suggest that DM is not a simple gene-dosage or gain-or-loss-of-function disorder but that entirely new pathological pathways at the DNA, RNA, or protein level may play a role in its manifestation.
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Affiliation(s)
- P Groenen
- Department of Cell Biology and Histology, Medical Faculty, University of Nijmegen, The Netherlands
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Makhdoum MJ, Hinderink JB, Snik AF, Groenen P, van den Broek P. Can event-related potentials be evoked by extra-cochlear stimulation and used for selection purposes in cochlear implantation? Clin Otolaryngol 1998; 23:432-8. [PMID: 9800079 DOI: 10.1046/j.1365-2273.1998.00168.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [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: 11/20/2022]
Abstract
To investigate whether electrically evoked event-related responses (P300) could be elicited by extra-cochlear stimulation, measurements were performed on a group of adults fitted with the single-channel extra-cochlear implant. To optimize measurement conditions, and because of the low number of subjects still using an extra-cochlear device in our cochlear implant programme, measurements were also performed on a group of experienced users fitted with the intra-cochlear Nucleus multichannel device. For reference purposes, subjects with normal hearing (control group) were also included in the study. Reproducible late latency responses (N1 and P2 peaks) were found in the five extra-cochlear implant users, while P300s were present in four out of these five subjects. The latencies were longer than those of the control group, but were similar to those obtained in the intra-cochlear implant group. Significant correlations were found for most N1, P2 and P300 measurements evoked by the tonal stimuli and by speech stimuli. The P300 amplitudes, evoked by either tonal or speech stimuli, appeared to be related to speech perception ability. This led to the conclusion that N1, P2 and P300 measurements may have potential as a clinical tool for preoperative prediction and postoperative evaluation of sound processing on a cortical level.
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Affiliation(s)
- M J Makhdoum
- Department of Otorhinolaryngology, University Hospital Nijmegen, The Netherlands
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Abstract
Vesico-ureteral reflux (VUR) is a frequent condition, but in most instances, the precise cause is unknown. We here review the evidence of a genetic aetiology of VUR, inherited as an autosomal dominant trait, with variable expression. We discuss the possible pathogenetic relationship between VUR and other types of uropathies and possible strategies towards the identification of genes underlying VUR are presented. The isolation of the gene(s) responsible for uropathies will not only lead to a better insight into the embryology of the urological system, the pathogenesis of uropathies, but also to a renewed interest from clinicians in congenital uropathies.
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Groenen P, Maassen B, Crul T. Formant transition duration and place perception in misarticulating children and adolescents. Clin Linguist Phon 1998; 12:439-457. [PMID: 21269125 DOI: 10.3109/02699209808985237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The explanation of articulatory problems as an output speech disorder does not preclude the possibility that auditory processing problems are associated. Identification of brief auditory spectral cues in a place-of-articulation continuum was studied in children with articulation problems. First, it was shown that formant transition durations smaller than 20·0 ms dramatically decreased phonemic identification rates for alveolar stop consonants in control subjects. Identification tasks based on two place-of-articulation continua /pαk/-/tαk/ with F2/F3 transition durations of 52 and 20 ms were administered to groups of misarticulating children and adolescents and two control groups (children and adults). For all subject groups there was poorer phonetic processing with shorter transition durations of F2 and F3. The misarticulating subjects demonstrated poorer phonetic processing of formant transitions than did the control subjects. Shortening F2/F3 transition duration did not differentially influence perceptual behaviour between the experimental and the control groups. In determining the causal link between perception and production, an explanation of perception preceding production was favoured. It was argued that, in addition to assessing the specificity between perception and production mechanisms, assessment of perception of formant transitions may have potential as a clinical tool for evaluating phonetic processing.
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Affiliation(s)
- P Groenen
- Institute of Medical Psychology, University Hospital Nijmegen, The Netherlands
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Groenen P, Snik A, van den Broek P. Electrically evoked auditory middle latency responses versus perception abilities in cochlear implant users. Audiology 1997; 36:83-97. [PMID: 9099406 DOI: 10.3109/00206099709071963] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Electrical auditory middle latency responses (EAMLRs) were recorded in a group of 12 postlingually and 4 congenitally deaf cochlear implant users. The EAMLRs of the postlingually deaf cochlear implant users were compared to behavioral measures of speech perception. All the cochlear implant users showed pronounced EAMLR morphology and amplitude. EAMLRs of congenitally deaf cochlear implant users were remarkably similar to those of postlingually deaf cochlear implant users. The difference in speech perception ability between congenitally deaf and postlingually deaf cochlear implant users did not seem to be caused by integrity differences of the neural generators of the auditory middle latency response. For the postlingually deaf subjects, EAMLR amplitude variation and interlatency variation seemed to be related to specific aspects of speech perception. The poorer performers demonstrated more diversity in the amplitude of the EAMLR component peaks and a more diffuse EAMLR peak latency organization across the electrodes than the better performers.
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Affiliation(s)
- P Groenen
- Department of Otorhinolaryngology, University Hospital Nijmegen, The Netherlands
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26
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Groenen P, Maassen B, Crul T, Thoonen G. The specific relation between perception and production errors for place of articulation in developmental apraxia of speech. J Speech Hear Res 1996; 39:468-482. [PMID: 8783127 DOI: 10.1044/jshr.3903.468] [Citation(s) in RCA: 16] [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] [Indexed: 05/22/2023]
Abstract
Developmental apraxia of speech is a disorder of phonological and articulatory output processes. However, it has been suggested that perceptual deficits may contribute to the disorder. Identification and discrimination tasks offer a fine-grained assessment of central auditory and phonetic functions. Seventeen children with developmental apraxia (mean age 8:9, years:months) and 16 control children (mean age 8:0) were administered tests of identification and discrimination of resynthesized and synthesized monosyllabic words differing in place-of-articulation of the initial voiced stop consonants. The resynthetic and synthetic words differed in the intensity of the third formant, a variable potentially enlarging their clinical value. The results of the identification task showed equal slopes for both subject groups, which indicates no phonetic processing deficit in developmental apraxia of speech. The hypothesized effect of the manipulation of the intensity of the third formant of the stimuli was not substantiated. However, the children with apraxia demonstrated poorer discrimination than the control children, which suggests affected auditory processing. Furthermore, analyses of discrimination performance and articulation data per apraxic subject demonstrated a specific relation between the degree to which auditory processing is affected and the frequency of place-of-articulation substitutions in production. This indicates the interdependence of perception and production. The results also suggest that the use of perceptual tasks has significant clinical value.
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Affiliation(s)
- P Groenen
- Department of Otorhinolaryngology, University Hospital Nijmegen, The Netherlands.
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27
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Groenen P, Snik A, van den Broek P. On the clinical relevance of mismatch negativity: results from subjects with normal hearing and cochlear implant users. Audiol Neurootol 1996; 1:112-24. [PMID: 9390795 DOI: 10.1159/000259190] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [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: 02/05/2023] Open
Abstract
Mismatch negativity (MMN) provides an objective measure for evaluating subjects with problems related to speech processing. For a valid neurophysiological profile of speech-processing mechanisms, an efficient procedure to elicit MMNs is needed. In Experiment 1 of this study, MMN recordings were conducted in adults with normal hearing on the effects of decreasing the duration of the interstimulus interval (ISI). Shortening ISI duration does not seem to have a high impact on the individual MMN quality, whereas it does influence group MMN quality. In Experiment 2, MMNs were elicited in a group of cochlear implant users by using a speech sound contrast/ba/-/da/. A group of good performers produced a significant MMN, whereas a group of moderate performers did not. There seems to be a relation between speech perception ability and MMN quality. To fundamentally understand the effects of electrical stimulation of the inner ear and to clinically adjust rehabilitation, diverse data are needed on different aspects of auditory processing. Optimizing the procedure to elicit and MMN is therefore of great clinical value.
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Affiliation(s)
- P Groenen
- Department of Otorhinolaryngology, University Hospital Nijmegen, The Netherlands
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Groenen P, Crul T, Maassen B, van Bon W. Perception of voicing cues by children with early otitis media with and without language impairment. J Speech Hear Res 1996; 39:43-54. [PMID: 8820698 DOI: 10.1044/jshr.3901.43] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Research on the relationship between early otitis media with effusion (OME), language impairment, and central auditory processing has been equivocal. Identification and discrimination tasks provide us with a sensitive method of assessing speech perception on both an auditory and a phonetic level. The present study examined identification and discrimination of initial bilabial stop consonants differing in voicing by 9-year-old children with a history of severe OME. The groups studied were controlled for language impairment. The ability of these children to perceive major and minor voicing cues was examined using multiple voicing cues. Long-term effects of OME were found for both identification and discrimination performance. Children with OME produced an overall inconsistency in categorization, which suggests poorer phonetic processing. Discrimination was measured by means of "just noticeable differences" (JND). Children with early OME experience demonstrated a greater mean JND than children without early OME experience. Finally, in cases of language impairment with early OME, there was no additional deterioration of auditory or phonetic processing. It appears that either early OME or language impairment can lead to poorer perception.
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Affiliation(s)
- P Groenen
- University Hospital Nijmegen, Department of Otorhinolaryngology, The Netherlands.
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