1
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Schwartzmann S, Zhao M, Sczakiel HL, Hildebrand G, Ehmke N, Horn D, Mensah MA, Boschann F. RNA analysis and computer-aided facial phenotyping help to classify a novel TRIO splice site variant. Am J Med Genet A 2024:e63599. [PMID: 38517182 DOI: 10.1002/ajmg.a.63599] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/26/2024] [Accepted: 03/08/2024] [Indexed: 03/23/2024]
Abstract
Pathogenic variants in TRIO, encoding the guanine nucleotide exchange factor, are associated with two distinct neurodevelopmental delay phenotypes: gain-of-function missense mutations within the spectrin repeats are causative for a severe developmental delay with macrocephaly (MIM: 618825), whereas loss-of-function missense variants in the GEF1 domain and truncating variants throughout the gene lead to a milder developmental delay and microcephaly (MIM: 617061). In three affected family members with mild intellectual disability/NDD and microcephaly, we detected a novel heterozygous TRIO variant at the last coding base of exon 31 (NM_007118.4:c.4716G>A). RNA analysis from patient-derived lymphoblastoid cells confirmed aberrant splicing resulting in the skipping of exon 31 (r.4615_4716del), leading to an in-frame deletion in the first Pleckstrin homology subdomain of the GEF1 domain: p.(Thr1539_Lys1572del). To test for a distinct gestalt, facial characteristics of the family members and 41 previously published TRIO cases were systematically evaluated via GestaltMatcher. Computational analysis of the facial gestalt suggests a distinguishable facial TRIO-phenotype not outlined in the existing literature.
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Affiliation(s)
- Sarina Schwartzmann
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Medizinische Genetik und Humangenetik, Berlin, Germany
| | - Max Zhao
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Medizinische Genetik und Humangenetik, Berlin, Germany
| | - Henrike Lisa Sczakiel
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Medizinische Genetik und Humangenetik, Berlin, Germany
- RG Development & Disease, Max Planck Institute for Molecular Genetics, Berlin, Germany
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, BIH Biomedical Innovation Academy, BIH Charité Junior Clinician Scientist Program, Berlin, Germany
| | - Gabriele Hildebrand
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Medizinische Genetik und Humangenetik, Berlin, Germany
| | - Nadja Ehmke
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Medizinische Genetik und Humangenetik, Berlin, Germany
| | - Denise Horn
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Medizinische Genetik und Humangenetik, Berlin, Germany
| | - Martin A Mensah
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Medizinische Genetik und Humangenetik, Berlin, Germany
- RG Development & Disease, Max Planck Institute for Molecular Genetics, Berlin, Germany
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, BIH Biomedical Innovation Academy, BIH Charité Digital Clinician Scientist Program, Berlin, Germany
| | - Felix Boschann
- Charité-Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Medizinische Genetik und Humangenetik, Berlin, Germany
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, BIH Biomedical Innovation Academy, BIH Charité, Clinician Scientist Program, Berlin, Germany
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2
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Boschann F, Kosmehl S, Bloching M, Grünhagen J, Hildebrand G, Horn D, Lyutenski S. Novel noncanonical splice site variant causes mild CHD7-related disorder with variable intrafamilial expressivity. Am J Med Genet A 2023; 191:1128-1132. [PMID: 36708132 DOI: 10.1002/ajmg.a.63122] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/05/2023] [Accepted: 01/09/2023] [Indexed: 01/29/2023]
Abstract
The clinical diagnosis criteria for CHARGE syndrome have been revised several times in the last 25 years. Variable expressivity and reduced penetrance are known, particularly in mild and familial cases. Therefore, it has been proposed to include the detection of a pathogenic CHD7 variant as a major diagnostic criterion. However, intronic variants not located at the canonical splice site are still underrepresented in mutation databases, often because functional analysis is not performed in the diagnostic setting. Here, we report a two-generation family that did not meet the criteria for CHARGE syndrome, until the molecular findings were taken into account. By exome sequencing, we detected an intronic variant in a male individual, who presented with unilateral external ear malformation, bilateral semicircular canal aplasia, polydactyly, vertebral body fusion and a heart defect. The variant was inherited by his mother, who also had bilateral semicircular canal aplasia additionally to unilateral sensorineural hearing impairment, unilateral mandibular palpebral synkinesia, orofacial cleft, and dysphagia. Using RNA studies, we were able to demonstrate that aberrant splicing occurs at an upstream cryptic splice acceptor site, resulting in a frameshift and premature stop of translation. Our data show causality of the noncanonical intronic CHD7 variant and end the diagnostic odyssey of this unsolved phenotype of the family.
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Affiliation(s)
- Felix Boschann
- Institute of Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.,Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Biomedical Innovation Academy, BIH Charité Clinician Scientist Program, Berlin, Germany
| | - Sabine Kosmehl
- Department of Otorhinolaryngology, Helios Hospital Berlin-Buch, Berlin, Germany
| | - Marc Bloching
- Department of Otorhinolaryngology, Helios Hospital Berlin-Buch, Berlin, Germany
| | - Johannes Grünhagen
- Labor Berlin Charité Vivantes GmbH-Corporate Member of Institute for Medical Genetics and Human Genetics, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Gabriele Hildebrand
- Institute of Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Denise Horn
- Institute of Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Stefan Lyutenski
- Department of Otorhinolaryngology, Helios Hospital Berlin-Buch, Berlin, Germany
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3
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Holtgrewe M, Knaus A, Hildebrand G, Pantel JT, Santos MRDL, Neveling K, Goldmann J, Schubach M, Jäger M, Coutelier M, Mundlos S, Beule D, Sperling K, Krawitz PM. Multisite de novo mutations in human offspring after paternal exposure to ionizing radiation. Sci Rep 2018; 8:14611. [PMID: 30279461 PMCID: PMC6168503 DOI: 10.1038/s41598-018-33066-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [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: 05/25/2018] [Accepted: 09/12/2018] [Indexed: 12/30/2022] Open
Abstract
A genome-wide evaluation of the effects of ionizing radiation on mutation induction in the mouse germline has identified multisite de novo mutations (MSDNs) as marker for previous exposure. Here we present the results of a small pilot study of whole genome sequencing in offspring of soldiers who served in radar units on weapon systems that were emitting high-frequency radiation. We found cases of exceptionally high MSDN rates as well as an increased mean in our cohort: While a MSDN mutation is detected in average in 1 out of 5 offspring of unexposed controls, we observed 12 MSDNs in altogether 18 offspring, including a family with 6 MSDNs in 3 offspring. Moreover, we found two translocations, also resulting from neighboring mutations. Our findings indicate that MSDNs might be suited in principle for the assessment of DNA damage from ionizing radiation also in humans. However, as exact person-related dose values in risk groups are usually not available, the interpretation of MSDNs in single families would benefit from larger molecular epidemiologic studies on this new biomarker.
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Affiliation(s)
- Manuel Holtgrewe
- Berlin Institute of Health (BIH), Core Unit Bioinformatics, Berlin, 10178, Germany.,Charité - Universitätsmedizin Berlin, Berlin, 10117, Germany
| | - Alexej Knaus
- Institute for Genomic Statistics and Bioinformatics, Rheinische Friedrich-Wilhelms Universität, Bonn, 53127, Germany
| | - Gabriele Hildebrand
- Charité - Universitätsmedizin Berlin, Institute of Medical and Human Genetics, 13353, Berlin, Germany
| | - Jean-Tori Pantel
- Charité - Universitätsmedizin Berlin, Institute of Medical and Human Genetics, 13353, Berlin, Germany
| | | | - Kornelia Neveling
- Department for Human Genetics, Radboud University, Nijmegen, 6525, Netherlands
| | - Jakob Goldmann
- Department for Human Genetics, Radboud University, Nijmegen, 6525, Netherlands
| | - Max Schubach
- Charité - Universitätsmedizin Berlin, Institute of Medical and Human Genetics, 13353, Berlin, Germany.,Berlin Institute of Health (BIH), JRG Computational Genome Biology, 10178, Berlin, Germany
| | - Marten Jäger
- Charité - Universitätsmedizin Berlin, Institute of Medical and Human Genetics, 13353, Berlin, Germany
| | - Marie Coutelier
- Charité - Universitätsmedizin Berlin, Institute of Medical and Human Genetics, 13353, Berlin, Germany
| | - Stefan Mundlos
- Charité - Universitätsmedizin Berlin, Institute of Medical and Human Genetics, 13353, Berlin, Germany
| | - Dieter Beule
- Berlin Institute of Health (BIH), Core Unit Bioinformatics, Berlin, 10178, Germany.,Max Delbrück Center for Molecuar Medicine, 13125, Berlin, Germany
| | - Karl Sperling
- Charité - Universitätsmedizin Berlin, Institute of Medical and Human Genetics, 13353, Berlin, Germany
| | - Peter Michael Krawitz
- Institute for Genomic Statistics and Bioinformatics, Rheinische Friedrich-Wilhelms Universität, Bonn, 53127, Germany.
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4
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Dietz A, Flentje M, Hagen R, Kortmann RD, Hildebrand G, Hoppe F, Schwienhorst I, Keilholz U. Docetaxel, cisplatin (TP), and radiation with or without cetuximab in advanced larynx carcinoma (DeLOS II trial). J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.tps265] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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5
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Schade R, Hildebrand G, Liefeith K. NEUE SYSTEME FÜR DIE PRÜFUNG ZAHNÄRZTLICHER WERKSTOFFE. BIOMED ENG-BIOMED TE 2009. [DOI: 10.1515/bmte.2000.45.s1.133] [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: 11/15/2022]
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6
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Androwitsch M, Islam R, Hildebrand G. Phasenanalytische Bestimmung des Bindegewebsanteils in Fleischerzeugnissen. J Verbrauch Lebensm 2009. [DOI: 10.1007/s00003-009-0459-4] [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: 10/21/2022]
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7
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Schmidt E, Racenberg E, Hildebrand G, Büch U. Komplikationen und Gefahren der Plexusbrachialis-Anästhesie unter besonderer Berücksichtigung von Langzeitschäden. Anasthesiol Intensivmed Notfallmed Schmerzther 2008. [DOI: 10.1055/s-2007-1005398] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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8
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Senyah N, Hildebrand G, Liefeith K. Comparison between RGD-peptide-modified titanium and borosilicate surfaces. Anal Bioanal Chem 2005; 383:758-62. [PMID: 16151591 DOI: 10.1007/s00216-005-3274-5] [Citation(s) in RCA: 11] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Revised: 04/11/2005] [Accepted: 04/20/2005] [Indexed: 11/24/2022]
Abstract
The use of synthetic peptides containing adhesive sequences, such as the Arg-Gly-Asp (RGD) motif, represents a promising strategy to control biological interactions at the cell-material interface. These peptides are known to improve the tissue-material contact owing to highly specific binding to cellular membrane receptors known as integrins, thereby promoting the adhesion, migration and proliferation of cells. The peptides were coupled to borosilicate glass and titanium surfaces using silanisation chemistry. A tryptophan residue was incorporated into the amino acid sequences of selected peptides to facilitate the detection of the covalently bound peptides. Successful peptide immobilisation was proven by fluorimetric measurements. The confocal imaging analysis suggests a homogeneous distribution of the immobilised peptide across the biomaterial surface. In vitro cell proliferation assays were employed to compare the adhesion potentials of the well-known RGD-containing peptides GRGDSP, GRADSP and RGDS to the three peptides designed by our group. The results demonstrate that the RGD sequence is not necessarily required to enhance the adhesion of cells to non-biological surfaces. Moreover, it is shown that the number of adhering cells can be increased by changes in the peptide hydrophobicity. Changes in the cytoskeleton are observed depending on the type of RGD-peptide modification.
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Affiliation(s)
- N Senyah
- Department of Biomaterials, Institute for Bioprocessing and Analytical Measurement Techniques e.V. (iba), Rosenhof, 37308 Heilbad Heiligenstadt, Germany
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9
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Yang YG, Herceg Z, Nakanishi K, Demuth I, Piccoli C, Michelon J, Hildebrand G, Jasin M, Digweed M, Wang ZQ. The Fanconi anemia group A protein modulates homologous repair of DNA double-strand breaks in mammalian cells. Carcinogenesis 2005; 26:1731-40. [PMID: 15905196 DOI: 10.1093/carcin/bgi134] [Citation(s) in RCA: 56] [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: 12/28/2022] Open
Abstract
Fanconi anemia (FA) cells exhibit hypersensitivity to DNA interstrand cross-links (ICLs) and high levels of chromosome instability. FA gene products have been shown to functionally or physically interact with BRCA1, RAD51 and the MRE11/RAD50/NBS1 complex, suggesting that the FA complex may be involved in the repair of DNA double-strand breaks (DSBs). Here, we have investigated specifically the function of the FA group A protein (FANCA) in the repair of DSBs in mammalian cells. We show that the targeted deletion of Fanca exons 37-39 generates a null for Fanca in mice and abolishes ubiquitination of Fancd2, the downstream effector of the FA complex. Cells lacking Fanca exhibit increased chromosomal aberrations and attenuated accumulation of Brca1 and Rad51 foci in response to DNA damage. The absence of Fanca greatly reduces gene-targeting efficiency in mouse embryonic stem (ES) cells and compromises the survival of fibroblast cells in response to ICL agent treatment. Fanca-null cells exhibit compromised homology-directed repair (HDR) of DSBs, particularly affecting the single-strand annealing pathway. These data identify the Fanca protein as an integral component in the early step of HDR of DSBs and thereby minimizing the genomic instability.
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Affiliation(s)
- Yun-Gui Yang
- International Agency for Research on Cancer (IARC), 150 cours Albert Thomas, F-69008 Lyon, France
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10
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Kracker S, Bergmann Y, Demuth I, Frappart PO, Hildebrand G, Christine R, Wang ZQ, Sperling K, Digweed M, Radbruch A. Nibrin functions in Ig class-switch recombination. Proc Natl Acad Sci U S A 2005; 102:1584-9. [PMID: 15668383 PMCID: PMC547877 DOI: 10.1073/pnas.0409191102] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Nijmegen breakage syndrome (NBS) is a rare autosomal recessive disorder characterized by predisposition to hematopoietic malignancy, cell-cycle checkpoint defects, and ionizing radiation sensitivity. NBS is caused by a hypomorphic mutation of the NBS1 gene, encoding nibrin, which forms a protein complex with Mre11 and Rad50, both involved in DNA repair. Nibrin localizes to chromosomal sites of class switching, and B cells from NBS patients show an enhanced presence of microhomologies at the sites of switch recombination. Because nibrin is crucial for embryonic survival, direct demonstration by targeted deletion that nibrin functions in class switch recombination has been lacking. Here, we show by cell-type-specific conditional inactivation of Nbn, the murine homologue of NBS1, that nibrin plays a role in the repair of gamma-irradiation damage, maintenance of chromosomal stability, and the recombination of Ig constant region genes in B lymphocytes.
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Affiliation(s)
- Sven Kracker
- German Rheumatism Research Center, Schumannstrasse 21-22, 10117 Berlin, Germany
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11
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Demuth I, Frappart PO, Hildebrand G, Melchers A, Lobitz S, Stöckl L, Varon R, Herceg Z, Sperling K, Wang ZQ, Digweed M. An inducible null mutant murine model of Nijmegen breakage syndrome proves the essential function of NBS1 in chromosomal stability and cell viability. Hum Mol Genet 2004; 13:2385-97. [PMID: 15333589 DOI: 10.1093/hmg/ddh278] [Citation(s) in RCA: 58] [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: 11/12/2022] Open
Abstract
The human genetic disorder, Nijmegen breakage syndrome, is characterized by radiosensitivity, immunodeficiency, chromosomal instability and an increased risk for cancer of the lymphatic system. The NBS1 gene codes for a protein, nibrin, involved in the processing/repair of DNA double strand breaks and in cell cycle checkpoints. Most patients are homozygous for a founder mutation, a 5 bp deletion, which might not be a null mutation, as functionally relevant truncated nibrin proteins are observed, at least in vitro. In agreement with this hypothesis, null mutation of the homologous gene, Nbn, is lethal in mice. Here, we have used Cre recombinase/loxP technology to generate an inducible Nbn null mutation allowing the examination of DNA-repair and cell cycle-checkpoints in the complete absence of nibrin. Induction of Nbn null mutation leads to the loss of the G2/M checkpoint, increased chromosome damage, radiomimetic-sensitivity and cell death. In vivo, this particularly affects the lymphatic tissues, bone marrow, thymus and spleen, whereas liver, kidney and muscle are hardly affected. In vitro, null mutant murine fibroblasts can be rescued from cell death by transfer of human nibrin cDNA and, more significantly, by a cDNA carrying the 5 bp deletion. This demonstrates, for the first time, that the common human mutation is hypomorphic and that the expression of a truncated protein is sufficient to restore nibrin's vital cellular functions.
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Affiliation(s)
- Ilja Demuth
- Institut für Humangenetik, Charité Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin, Germany
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12
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Hildebrand G, Kunze S, Driver M. Blood cell adhesion on sensor materials studied by light, scanning electron, and atomic-force microscopy. Ann Biomed Eng 2001; 29:1100-5. [PMID: 11853262 DOI: 10.1114/1.1424919] [Citation(s) in RCA: 5] [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: 11/24/2022]
Abstract
Unwanted interactions of biomedical sensors with surrounding tissues, body fluids, and cells are one of the most crucial problems affecting their long-term stability. In vivo processes were simulated in a computer-controlled bioreactor connected to a flow chamber system. Optical sensor materials were inserted into a parallel-plate chamber and monitored by light microscopy in order to get information about the number of adhered cells. Tests with thrombocyte-enriched plasma show that novel phosphorylcholine (PC)-polymer-coated sensors appear to be more bioinert, and thus demonstrate better haemocopatibility in comparison with untreated glass sensors. The influence of different materials on the morphology of adhered cells was investigated by off-line methods such as scanning electron microscopy (SEM) and atomic-force microscopy (AFM). SEM showed a reduction in the number of adhered thrombocytes and the lack of any fibrin network on the PC-polymer-modified glass surface, in contrast to the pure glass surface. AFM gives topographical information, and the calculated contact areas and cell volumes indicate smaller interactions between cells and sensor material in the case of PC-polymer-coated sensors.
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Affiliation(s)
- G Hildebrand
- Institute for Bioprocessing and Analytical Measurement Techniques e.V., Heilbad Heiligenstadt, Germany.
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13
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Navarro F, Orellana G, Moreno-Bondi MC, Vick T, Driver M, Hildebrand G, Liefeith K. Fiber-optic luminescent sensors with composite oxygen-sensitive layers and anti-biofouling coatings. Anal Chem 2001; 73:5150-6. [PMID: 11721912 DOI: 10.1021/ac015517n] [Citation(s) in RCA: 23] [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: 11/30/2022]
Abstract
Anti-biofouling polymers containing phosphorylcholine (PC)-substituted methacrylate units have been prepared by copolymerization with dodecyl methacrylate and used to coat luminescent oxygen sensors. Nanometer-sized coatings of such materials are shown to reduce significantly the adhesion of marine bacteria (more than 70%) and thrombocytes (more than 90%) to the surface of tris-(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)-doped silicone layers. A thorough analytical characterization of both the PC-coated and the uncoated dyed films has demonstrated that the anti-biofouling layers do not alter dramatically the performance of the fiber-optic oxygen sensors in aqueous media and are mechanically stable for more than one year of continuous immersion. The slope of the linear calibration plots in the 0-8 mg L(-1) oxygen concentration range (ca. 1.0 L mg(-1)) decreases 8-11% after applying the 50-nm protective layer with no change in the sensor precision (1.1-1.9% RSD, n = 6). The response time of the 200-microm O2-sensitive layers (1.5-6 min) increases up to 2-fold, depending on the nature of the PC polymer used, but the temperature effect on the sensor response (0.020 L mg(-1) degrees C(-1)) remains essentially unchanged. Oxygen detection limits as low as 0.04 mg L(-1) have been measured with the coated optodes. The novel biofouling-resistant optosensors have been successfully validated against a commercial oxygen electrode and are shown to respond faster than the electrochemical device for large oxygen concentration changes. The biomimetic coatings will be particularly useful for drift-free long-term operation of environmental optosensors and in vivo fiber-optic oxygen analyzers.
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Affiliation(s)
- F Navarro
- Department of Organic Chemistry, Universidad Complutense de Madrid, Spain
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14
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Hildebrand G, Liefeith K, Hofinger J. IN-VITRO BIOKOMPATIBILITÄTSUNTERSUCHUNGEN AN ELEKTROCHEMISCH ABGESCHIEDENEN CA/P-SCHICHTEN. BIOMED ENG-BIOMED TE 2000. [DOI: 10.1515/bmte.2000.45.s1.115] [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: 11/15/2022]
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15
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Schoenen J, Bulcke J, Caekebeke J, Dehaene I, De Keyser J, Hildebrand G, Joffroy A, Laloux P, Louis P, Monseu G. Self-treatment of acute migraine with subcutaneous sumatriptan using an auto-injector device: comparison with customary treatment in an open, longitudinal study. Cephalalgia 1994; 14:55-63. [PMID: 8200027 DOI: 10.1046/j.1468-2982.1994.1401055.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In a multicenter open longitudinal clinical trial where 479 patients suffering from migraine with or without aura were recruited, patients treated at home one to three migraine attacks with their customary treatment, and subsequently, over a 3-month period, one to three migraine attacks with 6 mg sumatriptan sc using an autoinjector. The headache response to customary treatment was 19% at 1 h and 30.5% at 2 h, and was not significantly different when only attacks treated "adequately" according to accepted treatment recommendations were considered: 16% at 1 h and 35% at 2 h. In contrast, 69% and 82% of patients treated with 6 mg sumatriptan sc had mild headache or no headache at 1 and 2 h respectively, regardless of migraine type or duration of symptoms prior to treatment. Other migraine symptoms (nausea, vomiting, photo- and phonophobia) were effectively treated with sumatriptan. Recurrence of migraine was observed in 31% of patients and was well controlled by a second injection of sumatriptan. It is concluded that 6 mg sumatriptan sc, self-administered using an autoinjector, is well tolerated and more effective than most currently used acute treatments for migraine in a population of severely affected patients consulting a neurologist.
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Affiliation(s)
- J Schoenen
- University Department of Neurology, CHR Citadelle, Liège, Belgium
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16
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Lenzen J, Hildebrand G, Laun A, Stracke H, Müller H, Schatz H. Function tests on the neuroendocrine hypothalamo-pituitary system following acute midbrain syndrome, with special reference to computertomographical and magnetic resonance imaging results. Neurosurg Rev 1993; 16:183-7. [PMID: 8272206 DOI: 10.1007/bf00304325] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 01/29/2023]
Abstract
Seventeen patients underwent a neuroendocrinological function test at a mean 6.3 years following a severe craniocerebral trauma (CCT) accompanied by midbrain syndrome. An insulin hypoglycaemia test (IHT) and the combined pituitary anterior lobe test (CPALT) were applied. Whereas the IHT as maximum stimulator of the hypothalamo-pituitary system (HPS) showed an adequate reserve capacity, the CPALT yielded a partial limitation of the secretion dynamic in the somatotropic, adrenocorticotropic axis as well as a dysfunction in the FSH secretion. Neuroradiological tests could not establish substantial injury in the regio hypothalamica in any patient.
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Affiliation(s)
- J Lenzen
- Department of Neurosurgery, Justus Liebig University, Giessen, Fed. Rep. of Germany
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Abstract
We have examined two T lymphocyte cell surface molecules, CD4 and CD7, as targets for specific delivery of drugs from antibody-directed liposomes. The efficiency of uptake by peripheral lymphocytes, thymocytes, and two CEM sublines (CEM.MRS and CEM-T4) of anti-CD4 and anti-CD7 liposomes containing methotrexate was evaluated by the methotrexate-mediated inhibition of the incorporation of d-[3H]Urd into DNA. This was compared with similar liposomes targeted to MHC-encoded HLA class I molecules, which are known to be efficiently taken up by T cells. Despite the lower expression of CD7 molecules relative to HLA class I on most cell lines, CD7 was shown to be a good target for drug delivery. The results of an internalization study using radiolabeled Protein A showed that a higher proportion of CD7 molecules was internalized than HLA class I molecules. CD4-targeted liposomes, in contrast, were relatively ineffective for drug delivery for lymphoid cells, and only partially inhibited CEM-T4 cells. The lack of toxicity correlated with poor internalization of the target molecule on most cell lines. The drug effect of anti-CD4 liposomes was more pronounced on HeLa-T4, which is an epithelial cell line transfected with the CD4 gene. In contrast to lymphoid cells, these cells efficiently internalized CD4 molecules. PMA is known to down-regulate surface expression of CD4 molecules on various T cells. Internalization of CD4 was induced by PMA, but PMA failed to induce cytotoxicity of CD4-targeted liposomes for CEM.MRS. The internalized drug was probably degraded rapidly because internalized anti-CD4 antibody-bound Protein A was degraded very rapidly.
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Affiliation(s)
- H Suzuki
- Centre d'Immunologie INSERM-CNRS de Marseille-Luminy, France
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18
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Schmidt E, Racenberg E, Hildebrand G, Büch U. [Complications and risks of brachial plexus anaesthesia with special reference to long-term damage (author's transl)]. Anasth Intensivther Notfallmed 1981; 16:346-9. [PMID: 7325349] [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: 01/24/2023]
Abstract
During 1974-1978 620 regional anaesthesias involving the brachial plexus were performed. Three techniques, viz: supraclavicular, axillary, interscalene were employed. The data are analysed with a view to comparing the efficacy and safety of the techniques with a special reference to long-term damage. Transient injury to the brachial plexus was observed in 3 of 342 patients who had Kulenkampff's supraclavicular plexus anaesthesia. After 3 months all after-effects had disappeared. Plexus block via the axillary route proved to be the safest technique. Detailed inquiries and follow-up examinations established that none of the techniques had caused irreversible damage to the brachial plexus.
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19
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Dausch-Neumann D, Hildebrand G. Buchbesprechungen. J Orofac Orthop 1961. [DOI: 10.1007/bf02165807] [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: 10/25/2022]
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20
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Leibnitz E, Hager W, Berthold P, Hildebrand G. Studien zur Chemie der Paraffine und Paraffinmassen. I. Bestimmung von Paraffinen, Olefinen und Naphthenen in Folgeprodukten der Braunkohlenteerdestillation. ACTA ACUST UNITED AC 1958. [DOI: 10.1002/prac.19580070108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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21
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Hildebrand G. Depressorische Adrenalinwirkung und Adrenalinumkehr. Naunyn Schmiedebergs Arch Pharmacol 1952. [DOI: 10.1007/bf00250127] [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]
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